identifier
stringlengths 11
32
| pdf_url
stringlengths 17
4.62k
⌀ | lang
stringclasses 120
values | error
stringclasses 1
value | title
stringlengths 2
500
⌀ | source_name
stringlengths 1
435
⌀ | publication_year
float64 1.9k
2.02k
| license
stringclasses 3
values | word_count
int64 0
1.64M
| text
stringlengths 1
9.75M
|
|---|---|---|---|---|---|---|---|---|---|
https://openalex.org/W4362625832
|
https://figshare.com/articles/journal_contribution/Supplementary_Figure_1_from_Sulindac_Metabolites_Induce_Proteosomal_and_Lysosomal_Degradation_of_the_Epidermal_Growth_Factor_Receptor/22525727/1/files/39988559.pdf
|
Norwegian Nynorsk
| null |
Supplementary Figure 2 from Sulindac Metabolites Induce Proteosomal and Lysosomal Degradation of the Epidermal Growth Factor Receptor
| null | 2,023
|
cc-by
| 22
|
A. Pangburn Supplemental Figure S1 A. Pangburn Supplemental Figure S1 ather A. Pangburn Supplemental Figure S1 er A. Pangburn Supplemental Figure S1
|
https://openalex.org/W3010226549
|
https://zenodo.org/record/4509390/files/Hajduk_SFWcode_PhilTrans.pdf
|
English
| null |
The ‘algebra of evolution’: the Robertson–Price identity and viability selection for body mass in a wild bird population
|
Philosophical transactions - Royal Society. Biological sciences
| 2,020
|
cc-by
| 728
|
R code : The Robertson-Price Identity and viability selection for
body mass in superb fairy-wrens
Philosophical Transactions of the Royal Society of London B November 2019 modelI <- MCMCglmm(cbind(weight, alive41daysF) ~ trait-1 modelI <- MCMCglmm(cbind(weight, alive41daysF) ~ trait-1 + trait:genF + trait:helpersCat + trait:broodSize + trait:sexFac + trait:genF + trait:helpersCat + trait:broodSize + trait + at.level(trait, 1):chickAge +
at.level(trait, 1):I(chickAgeˆ2)
+ at level(trait
1):pre1992 + trait:WPO + at.level(trait, 1):chickAge +
at.level(trait, 1):I(chickAgeˆ2) + at.level(trait, 1):pre1992 + trait:WPO, random = ~ us(trait):animal + us(trait):nestID + us(trait):cohortFac + us(trait):HatchDateFac,
rcov = ~ us(trait):units,
data = nestlings,
ginverse=list(animal=Ainv.MCMCglmm),
f
il
("
i
"
" h
h ld") random = ~ us(trait):animal + us(trait):nestID + us(trait):cohortFac + us(trait):HatchDateFac,
rcov = ~ us(trait):units, diag(autocorr(modelI$VCV)[2, , ]) diag(autocorr(modelI$VCV)[2, , ]) 1 # CALCULATE PROPORTIONS # CALCULATE PROPORTIONS prop.Va.surv<-Va.surv/Vp.surv
mean(prop.Va.surv)
HPDinterval(prop.Va.surv) 2 # cohort HPDinterval(prop.Vcohort.mass) prop.Vcohort.surv<-modelI$VCV[,"traitalive41daysF:traitalive41daysF.cohortFac"]/Vp.surv
mean(prop.Vcohort.surv)
HPDinterval(prop.Vcohort.surv) prop.Vcohort.surv<-modelI$VCV[,"traitalive41daysF:traitalive41daysF.cohortFac"]/Vp.surv
mean(prop.Vcohort.surv)
HPDinterval(prop.Vcohort.surv) mean(prop.Vcohort.surv)
HPDinterval(prop.Vcohort.surv)
# ----------------------------------------
# COVARIANCE BETWEEN MASS AND SURVIVAL
# ----------------------------------------
### phenotypic selection gradient
CovP<-modelI$VCV[,"traitalive41daysF:traitweight.animal"]+
modelI$VCV[,"traitalive41daysF:traitweight.nestID"]+
modelI$VCV[,"traitalive41daysF:traitweight.cohortFac"]+
modelI$VCV[,"traitalive41daysF:traitweight.HatchDateFac"]+
modelI$VCV[,"traitalive41daysF:traitweight.units"]
mean(CovP)
HPDinterval(CovP)
CovA<-modelI$VCV[,"traitalive41daysF:traitweight.animal"]
mean(CovA)
HPDinterval(CovA)
CovE<-modelI$VCV[,"traitalive41daysF:traitweight.nestID"]+
modelI$VCV[,"traitalive41daysF:traitweight.cohortFac"]+
modelI$VCV[,"traitalive41daysF:traitweight.HatchDateFac"]+
modelI$VCV[,"traitalive41daysF:traitweight.units"]
mean(CovE)
HPDinterval(CovE)
CovHatchDate<-modelI$VCV[,"traitalive41daysF:traitweight.HatchDateFac"]
mean(CovHatchDate)
HPDinterval(CovHatchDate)
# estimate % of distribution that is negative
100*table(CovHatchDate<0)/length(CovHatchDate)
CovCohort<-modelI$VCV[,"traitalive41daysF:traitweight.cohortFac"]
mean(CovCohort)
HPDinterval(CovCohort)
# estimate % of distribution that is negative
100*table(CovCohort<0)/length(CovCohort)
# ----------------------------------------
# CORRELATIONS BETWEEN MASS AND SURVIVAL
# ----------------------------------------
## animal
r_g <- modelI$VCV[,"traitalive41daysF:traitweight.animal"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.animal"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.animal"])) # ----------------------------------------
# COVARIANCE BETWEEN MASS AND SURVIVAL
# ----------------------------------------
### phenotypic selection gradient
CovP<-modelI$VCV[,"traitalive41daysF:traitweight.animal"]+
modelI$VCV[,"traitalive41daysF:traitweight.nestID"]+
modelI$VCV[,"traitalive41daysF:traitweight.cohortFac"]+
modelI$VCV[,"traitalive41daysF:traitweight.HatchDateFac"]+
modelI$VCV[,"traitalive41daysF:traitweight.units"]
mean(CovP)
HPDinterval(CovP)
CovA<-modelI$VCV[,"traitalive41daysF:traitweight.animal"]
mean(CovA)
HPDinterval(CovA)
CovE<-modelI$VCV[,"traitalive41daysF:traitweight.nestID"]+
modelI$VCV[,"traitalive41daysF:traitweight.cohortFac"]+
modelI$VCV[,"traitalive41daysF:traitweight.HatchDateFac"]+
modelI$VCV[,"traitalive41daysF:traitweight.units"]
mean(CovE)
HPDinterval(CovE)
CovHatchDate<-modelI$VCV[,"traitalive41daysF:traitweight.HatchDateFac"]
mean(CovHatchDate)
HPDinterval(CovHatchDate)
# estimate % of distribution that is negative
100*table(CovHatchDate<0)/length(CovHatchDate)
CovCohort<-modelI$VCV[,"traitalive41daysF:traitweight.cohortFac"]
mean(CovCohort)
HPDinterval(CovCohort)
# estimate % of distribution that is negative
100*table(CovCohort<0)/length(CovCohort)
# ----------------------------------------
# CORRELATIONS BETWEEN MASS AND SURVIVAL
# ----------------------------------------
## animal
r_g <- modelI$VCV[,"traitalive41daysF:traitweight.animal"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.animal"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.animal"])) # CORRELATIONS BETWEEN MASS AND SURVIVAL 3 mean(r_g)
HPDinterval(r_g)
## nestID
r_nest <- modelI$VCV[,"traitalive41daysF:traitweight.nestID"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.nestID"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.nestID"]))
mean(r_nest)
HPDinterval(r_nest) mean(r_g)
HPDinterval(r_g) mean(r_g)
HPDinterval(r_g)
## nestID
r_nest <- modelI$VCV[,"traitalive41daysF:traitweight.nestID"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.nestID"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.nestID"]))
mean(r_nest)
HPDinterval(r_nest)
## cohort
r_cohort <- modelI$VCV[,"traitalive41daysF:traitweight.cohortFac"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.cohortFac"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.cohortFac"]))
mean(r_cohort)
HPDinterval(r_cohort)
## hatch date fortnight
r_hatchdate <- modelI$VCV[,"traitalive41daysF:traitweight.HatchDateFac"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.HatchDateFac"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.HatchDateFac"]))
mean(r_hatchdate)
HPDinterval(r_hatchdate)
# --------------------------------------------------------------------
# model II
# bivariate model with Gaussian errors
# --------------------------------------------------------------------
# ------------------------------------------------------------
# generate relative survival within each cohort
# ------------------------------------------------------------
nestlings$alive41days<-as.numeric(nestlings$alive41daysF)
# estimate cohort means
cohort.mean.SurvFledgeToIndep<-tapply(nestlings$alive41days,nestlings$cohortFac,mean,na.rm=T)
# join to individual-level data
nestlings$cohortSurvFledgeToIndep<-cohort.mean.SurvFledgeToIndep[match(nestlings$cohortFac,
# create relative fitness value (individual survival relative to their cohort's mean)
nestlings$relSurv<-nestlings$alive41days/nestlings$cohortSurvFledgeToIndep
# check this has worked
tapply(nestlings$relSurv,nestlings$cohortFac,mean,na.rm=T)
# generate standardised weight
nestlings$stWeight<-scale(nestlings$weight,scale=T)
modelII <- MCMCglmm(cbind(stWeight, relSurv) ~ trait-1
+ trait:genF + trait:helpersCat + trait:broodSize + trait:sexFac
+ at.level(trait, 1):chickAge +
at.level(trait, 1):I(chickAgeˆ2)
+ at.level(trait, 1):pre1992 + trait:WPO,
random = ~ us(trait):animal + us(trait):nestID + us(trait):cohortFac + us(trait):HatchDate
rcov = ~ us(trait):units,
data = nestlings, HPDinterval(r_g)
## nestID
r_nest <- modelI$VCV[,"traitalive41daysF:traitweight.nestID"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.nestID"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.nestID"]))
mean(r_nest)
HPDinterval(r_nest) ## cohort
r_cohort <- modelI$VCV[,"traitalive41daysF:traitweight.cohortFac"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.cohortFac"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.cohortFac"]))
mean(r_cohort)
HPDinterval(r_cohort) ## cohort
r_cohort <- modelI$VCV[,"traitalive41daysF:traitweight.cohortFac"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.cohortFac"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.cohortFac"]))
mean(r_cohort)
HPDinterval(r_cohort) ## cohort
r_cohort <- modelI$VCV[,"traitalive41daysF:traitweight.cohortFac"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.cohortFac"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.cohortFac"]))
mean(r_cohort)
HPDinterval(r cohort) ## hatch date fortnight
r_hatchdate <- modelI$VCV[,"traitalive41daysF:traitweight.HatchDateFac"]/
(sqrt(modelI$VCV[,"traitweight:traitweight.HatchDateFac"])*
sqrt(modelI$VCV[,"traitalive41daysF:traitalive41daysF.HatchDateFac"]))
mean(r_hatchdate)
HPDinterval(r_hatchdate) tapply(nestlings$relSurv,nestlings$cohortFac,mean,na.rm=T) + at.level(trait, 1):chickAge +
at.level(trait, 1):I(chickAgeˆ2) + at.level(trait, 1):pre1992 + trait:WPO, random = ~ us(trait):animal + us(trait):nestID + us(trait):cohortFac + us(trait):HatchDateFac,
rcov = ~ us(trait):units,
data = nestlings, data = nestlings, 4 ginverse=list(animal=Ainv.MCMCglmm),
family = c("gaussian", "gaussian"),
nitt = def_nitt*400, thin = def_thin*200, burnin = def_burnin*400,
prior = prior.biv,
# prior
DIC = TRUE, verbose = TRUE,
slice = TRUE, pl = TRUE)
diag(autocorr(modelII$VCV)[2, , ])
summary(modelII$VCV)
# ----------------------------------
# ESTIMATE GRADIENTS
# ----------------------------------
Vp.mass.modelII<-modelII$VCV[,"traitstWeight:traitstWeight.animal"]+
modelII$VCV[,"traitstWeight:traitstWeight.nestID"]+
modelII$VCV[,"traitstWeight:traitstWeight.cohortFac"]+
modelII$VCV[,"traitstWeight:traitstWeight.HatchDateFac"]+
modelII$VCV[,"traitstWeight:traitstWeight.units"]
mean(Vp.mass.modelII)
Va.mass.modelII<-modelII$VCV[,"traitstWeight:traitstWeight.animal"]
mean(Va.mass.modelII)
Ve.mass.modelII<-modelII$VCV[,"traitstWeight:traitstWeight.nestID"]+
modelII$VCV[,"traitstWeight:traitstWeight.cohortFac"]+
modelII$VCV[,"traitstWeight:traitstWeight.HatchDateFac"]+
modelII$VCV[,"traitstWeight:traitstWeight.units"]
mean(Ve.mass.modelII)
#0.4532843
# ----------------------------------
### phenotypic gradient
# ----------------------------------
CovP.modelII<-modelII$VCV[,"traitrelSurv:traitstWeight.animal"]+
modelII$VCV[,"traitrelSurv:traitstWeight.nestID"]+
modelII$VCV[,"traitrelSurv:traitstWeight.cohortFac"]+
modelII$VCV[,"traitrelSurv:traitstWeight.HatchDateFac"]+
modelII$VCV[,"traitrelSurv:traitstWeight.units"]
mean(CovP.modelII)
Beta_P<-CovP.modelII/Vp.mass.modelII
mean(Beta_P)
HPDinterval(Beta_P)
# ----------------------------------
### genetic gradient
# ----------------------------------
CovA.modelII<-modelII$VCV[,"traitrelSurv:traitstWeight.animal"]
mean(CovA.modelII)
Beta A<-CovA modelII/Va mass modelII ginverse=list(animal=Ainv.MCMCglmm),
family = c("gaussian", "gaussian"),
nitt = def_nitt*400, thin = def_thin*200, burnin = def_burnin*400,
prior = prior.biv,
# prior
DIC = TRUE, verbose = TRUE,
slice = TRUE, pl = TRUE)
diag(autocorr(modelII$VCV)[2, , ])
summary(modelII$VCV)
# ----------------------------------
# ESTIMATE GRADIENTS
# ----------------------------------
Vp.mass.modelII<-modelII$VCV[,"traitstWeight:traitstWeight.animal"]+
modelII$VCV[,"traitstWeight:traitstWeight.nestID"]+
modelII$VCV[,"traitstWeight:traitstWeight.cohortFac"]+
modelII$VCV[,"traitstWeight:traitstWeight.HatchDateFac"]+
modelII$VCV[,"traitstWeight:traitstWeight.units"]
mean(Vp.mass.modelII)
Va.mass.modelII<-modelII$VCV[,"traitstWeight:traitstWeight.animal"]
mean(Va.mass.modelII)
Ve.mass.modelII<-modelII$VCV[,"traitstWeight:traitstWeight.nestID"]+
modelII$VCV[,"traitstWeight:traitstWeight.cohortFac"]+
modelII$VCV[,"traitstWeight:traitstWeight.HatchDateFac"]+
modelII$VCV[,"traitstWeight:traitstWeight.units"]
mean(Ve.mass.modelII)
#0.4532843
# ----------------------------------
### phenotypic gradient
# ----------------------------------
CovP.modelII<-modelII$VCV[,"traitrelSurv:traitstWeight.animal"]+
modelII$VCV[,"traitrelSurv:traitstWeight.nestID"]+
modelII$VCV[,"traitrelSurv:traitstWeight.cohortFac"]+
modelII$VCV[,"traitrelSurv:traitstWeight.HatchDateFac"]+
modelII$VCV[,"traitrelSurv:traitstWeight.units"]
mean(CovP.modelII)
Beta_P<-CovP.modelII/Vp.mass.modelII
mean(Beta_P)
HPDinterval(Beta_P)
# ----------------------------------
### genetic gradient
# ----------------------------------
CovA.modelII<-modelII$VCV[,"traitrelSurv:traitstWeight.animal"]
mean(CovA.modelII)
Beta_A<-CovA.modelII/Va.mass.modelII
mean(Beta_A)
HPDinterval(Beta_A) 5 # ----------------------------------
#### consistency test of whether CovA/VarA = CovP/VarP
# ----------------------------------
DifferenceBetaP_Beta_A<-Beta_P-Beta_A
mean(DifferenceBetaP_Beta_A)
HPDinterval(DifferenceBetaP_Beta_A)
100*table(DifferenceBetaP_Beta_A<0)/length(DifferenceBetaP_Beta_A)
# ----------------------------------
### environmental gradient
# ----------------------------------
CovE.modelII<-CovP.modelII-CovA.modelII
mean(CovE.modelII)
Beta_E<-CovE.modelII/Ve.mass.modelII
mean(Beta_E)
HPDinterval(Beta_E)
DifferenceBetaE_Beta_A<-Beta_E-Beta_A
mean(DifferenceBetaE_Beta_A)
HPDinterval(DifferenceBetaE_Beta_A)
100*table(DifferenceBetaE_Beta_A<0)/length(DifferenceBetaE_Beta_A) 6 6
|
https://openalex.org/W2124050982
|
http://www.ajnr.org/content/ajnr/36/6/1194.full.pdf
|
English
| null |
Different Spectral Hounsfield Unit Curve and High-Energy Virtual Monochromatic Image Characteristics of Squamous Cell Carcinoma Compared with Nonossified Thyroid Cartilage
|
American journal of neuroradiology
| 2,015
|
cc-by
| 6,102
|
ABSTRACT BACKGROUND AND PURPOSE: The attenuation of normal nonossified thyroid cartilage can be similar to that of head and neck squa-
mous cell carcinoma on CT. We compared dual-energy CT spectral Hounsfield unit attenuation characteristics of nonossified thyroid
cartilage with that of squamous cell carcinoma to determine the optimal virtual monochromatic image reconstruction energy levels for
distinguishing tumor from normal nonossified thyroid cartilage. MATERIALS AND METHODS: Dual-energy CT scans from 30 patients with histopathology-proved squamous cell carcinoma at different
primary sites (laryngeal and nonlaryngeal) and 10 healthy patients were evaluated. Patients were scanned with a 64-section single-source
scanner with fast-kilovolt (peak) switching, and scans were reconstructed at different virtual monochromatic energy levels ranging from 40
to 140 keV. Spectral attenuation curves of tumor and nonossified thyroid cartilage were quantitatively evaluated and compared. Any part
of the tumor invading the cartilage, when present, was excluded from ROI analysis to avoid cross-contamination from areas where there
could be a mixture of cartilage and invading tumor. RESULTS: Normal nonossified thyroid cartilage had a characteristic, predictable spectral attenuation curve that was different from
that of tumors. The greatest difference in attenuation of nonossified cartilage compared with tumor was on virtual monochromatic
images of 95 keV (P .0001), with sharp contrast between the relatively high attenuation of nonossified cartilage compared with
that of tumor. CONCLUSIONS: Head and neck squamous cell carcinoma has significantly different attenuation on virtual monochromatic images of 95
keV, compared with nonossified thyroid cartilage. ABBREVIATIONS: CNR contrast-to-noise ratio; DECT dual-energy CT; HNSCC head and neck squamous cell carcinoma; NOTC nonossified thyroid CONCLUSIONS: Head and neck squamous cell carcinoma has significantly different attenuation on virtual monochromatic images of 95
keV, compared with nonossified thyroid cartilage. ABBREVIATIONS: CNR contrast-to-noise ratio; DECT dual-energy CT; HNSCC head and neck squamous cell carcinoma; NOTC nonossified thyroid
cartilage; SHUAC spectral Hounsfield unit attenuation curve; VMI virtual monochromatic image tomy.1-7 An important aspect of staging is to determine whether
there is thyroid cartilage invasion.1,2,4-9 CT is typically the first-line
technique for evaluation of laryngeal cancer, but evaluation of thy-
roidcartilageinvasionremainsachallengeonCT,inlargepartdueto
variable ossification of the thyroid cartilage. Received October 13, 2014; accepted after revision December 14.
From the Department of Radiology (R.F., M.L., S.L.), Jewish General Hospital, McGill
University, Montreal, Quebec, Canada; Department of Radiology (R.G.), Massachu-
setts General Hospital, and Department of Radiology (N.D., H.D.C.), Massachusetts
Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts.
Abstract previously presented at: Annual Meeting of the American Society of
Head and Neck Radiology, September 10–14, 2014; Seattle, Washington.
Please address correspondence to Reza Forghani, MD, PhD, Department of Radiol-
ogy, Jewish General Hospital, Room C-212.1, 3755 Cote Ste-Catherine Rd, Montreal,
QC, Canada, H3T 1E2; e-mail: rforghani@jg.mcgill.ca
Indicates open access to non-subscribers at www.ajnr.org
Indicates article with supplemental on-line appendix and tables.
Indicates article with supplemental on-line photo.
http://dx.doi.org/10.3174/ajnr.A4253
1194
Forghani
Jun 2015
www.ajnr.org Cartilage
Compared with Nonossified Thyroid
Characteristics of Squamous Cell Carcinoma
High-Energy Virtual Monochromatic Image
Different Spectral Hounsfield Unit Curve and H.D. Curtin
R. Forghani, M. Levental, R. Gupta, S. Lam, N. Dadfar and of October 23, 2024. This information is current as of October 23, 2024. This information is current as http://www.ajnr.org/content/36/6/1194
https://doi.org/10.3174/ajnr.A4253
doi:
2015, 36 (6) 1194-1200
AJNR Am J Neuroradiol ORIGINAL RESEARCH
HEAD & NECK ORIGINAL RESEARCH
HEAD & NECK Different Spectral Hounsfield Unit Curve and High-Energy
Virtual Monochromatic Image Characteristics of Squamous
Cell Carcinoma Compared with Nonossified Thyroid Cartilage R. Forghani, M. Levental, R. Gupta, S. Lam, N. Dadfar, and H.D. Curtin Image Postprocessing and Analysis Quantitative image analysis was performed at the Advantage
Workstation 4.6 (GE Healthcare). Scans were retrospectively re-
constructed into different VMI energy levels ranging from 40 to
140 keV in 5-keV increments. Tumor and NOTC evaluation was
performed by measuring mean CT attenuation (in Hounsfield
unit SD) within ROIs across the entire range of VMI energy
levels. First, NOTC was evaluated in healthy patients. Eighteen ROIs
were placed in the NOTC in each patient, 9 on each side, to com-
pare and confirm similarity of the 2 sides. Thereafter, normal
NOTC and tumors were evaluated in 30 patients with HNSCC. In
this population, the NOTC and tumor were each evaluated with 9
ROIs placed on at least 3 separate sections. For tumors, the ROIs
were placed in the homogeneous-appearing enhancing part of the
tumor, avoiding areas of cystic change or necrosis. For NOTC,
ROIs were placed in the nonossified part of the thyroid cartilage,
avoiding the area immediately adjacent to a site of ossification. In healthy patients and in patients with tumor who had pri-
mary tumors outside the larynx, ROIs were placed bilaterally
within the NOTC. In patients with laryngeal cancers, ROIs
were placed in either the contralateral normal NOTC, or if
placed in the ipsilateral NOTC, they were placed in an area
separated by at least 5 sections (6 mm) from any area of contact
between tumor and cartilage. For evaluation of tumor in pa-
tients with laryngeal cancer, any part of the tumor adjacent to
or invading the cartilage, when present, was excluded from
quantitative ROI analysis to avoid cross-contamination from
areas where there could potentially be a mixture of cartilage
and invading tumor. On contrast-enhanced CT, NOTC has relatively high intrinsic
attenuation without measurable blood supply or iodine, whereas
HNSCC demonstrates increased attenuation secondary to increased
iodine content after administration of IV contrast. Therefore, be-
cause of their different compositions, we hypothesized that DECT
virtual monochromatic images reconstructed at different energy lev-
els may be useful in distinguishing tumor from nonossified thyroid
cartilage, and in this investigation, we compared the spectral
Hounsfield unit attenuation curve (SHUAC) characteristics of HN-
SCC with those of NOTC. The objective of our study was to evaluate
the differences in spectral attenuation and determine the optimal
virtual monochromatic image reconstruction energy levels for dis-
tinguishingtumorfromNOTC.Thisstudycomparedtheenhancing
part of tumor with normal nonossified thyroid cartilage. Image Postprocessing and Analysis Any part of
the tumor potentially invading the cartilage, when present, was ex-
cluded from quantitative ROI analysis to avoid cross-contamination
fromareaswheretherecouldpotentiallybeamixtureofcartilageand
invading tumor. A total of 693 ROIs were evaluated. The sizes of the ROIs
varied because of differences in thickness of the NOTC, tumor
size, and tumor homogeneity among patients. The minimum in-
dividual ROI diameter used was 1.5 mm (corresponding to a sam-
pled area per ROI of 1.77 mm2), and the maximum diameter used
was 5.5 mm (corresponding to a sampled area per ROI of 23.76
mm2). As discussed earlier, multiple, at least 9, ROIs were used
per structure, and the average ROI area evaluated per structure
(normal cartilage or tumor) was 86.8 mm2 (range, 21.2–212.1
mm2). The ROIs were averaged for each structure. So that the
results are not biased toward larger structures (eg, larger tumors), Image Acquisition All patients were scanned with the same 64-section dual-energy
scanner (Discovery CT750 HD; GE Healthcare, Milwaukee, Wis-
consin). All examinations were acquired after administration of
IV contrast. Eighty milliliters of iopamidol (Isovue 300; Bracco,
Princeton, New Jersey) was injected at a rate of 2 mL/s, and the
patient was scanned after a delay of 65 seconds. Scans were ac-
quired in dual-energy rapid 80- to 140-kV(p) switching mode by
using the Gemstone Spectral Imaging (GE Healthcare) protocol. These were acquired with a Gemstone Spectral Imaging preset 15,
with a large scan FOV (50 cm), 40-mm beam collimation, 0.6-
second rotation time, and 0.984:1 helical pitch. Images were re-
constructed into 1.25-mm sections in a 25-cm display FOV and
512 512 matrix. The average CT dose index volume for the
main acquisition (entire neck to the carina) was 17.3 mGy. information obtained from the different acquisitions can be com-
bined to generate image sets at different predicted energy levels
(kiloelectron volt [keV]), referred to as virtual monochromatic
images (VMI). Depending on their elemental properties, different
tissues have distinct attenuation, signal to noise, and contrast at
different VMI energy levels, enabling spectral evaluation of tissue
attenuation.16,17 Although currently there is only limited evi-
dence, emerging data demonstrate advantages of DECT for head
and neck imaging, with the potential for improved tumor visual-
ization and material characterization.18-21 Kuno et al22 have also
demonstrated that the addition of iodine overlay maps can in-
crease interobserver reproducibility and improve the specificity of
CT for determination of cartilage invasion without decreasing
sensitivity compared with conventional CT images alone. AJNR Am J Neuroradiol 36:1194–200
Jun 2015
www.ajnr.org ABSTRACT Although tumor has a
different appearance from both the cortex and the fat-filled medul-
lary space of ossified cartilage, the attenuation values of tumor and
nonossified thyroid cartilage (NOTC) are very similar.1,10,11 Several
criteriahavebeenevaluatedandproposedtoimprovetheaccuracyof
CT for detection of cartilage invasion, but none are perfect.1,2,11-14 H
ead and neck squamous cell carcinoma (HNSCC) is a com-
mon malignancy of the larynx and hypopharynx. Imaging
plays a key role in staging of laryngeal and hypopharyngeal can-
cers, and accurate staging is necessary to help determine whether
a patient will undergo organ-preserving treatment or laryngec- H Dual-energy CT (DECT) evaluates tissues at different x-ray
energies, enabling spectral evaluation and material tissue charac-
terization.15 With DECT, projection data are typically obtained
simultaneously or near-simultaneously at 80 and 140 kilovolts
(peak) (kV[p]).16,17 The measured values at the different acquisi-
tion energies can then be normalized to specific combinations of 2
different reference materials, such as iodine, water, or calcium. Furthermore, with sophisticated reconstruction algorithms, the 1194 Summary of primary HNSCC tumor sites evaluated
Primary Site
No. of
Patients
Untreated tumors (n 22)
Larynx
7a
Hypopharynx
1
Retromolar trigone, anterior tonsillar pillar
3
Oral cavity, other
5
Oropharynx, other
3
Sinuses, nose
3
Recurrent or metastatic tumors (n 8)
HNSCC invading parotid (n 2), parapharyngeal
space metastasis, oral cavity (n 2), base of tongue,
cheek, neopharynx
a Three of 7 laryngeal tumors had pathologically proven thyroid cartilage invasion. Summary of primary HNSCC tumor sites evaluated MATERIALS AND METHODS
Patients The study was approved by the institutional review board. Thirty
patients with proved HNSCC (by biopsy and/or surgery) and 10
healthy patients who had undergone DECT between June 2013
and July 2014 were retrospectively evaluated. Tumors from dif-
ferent primary sites were evaluated and are summarized in the
Table. They included 7 patients with laryngeal carcinoma and 1
patient with hypopharyngeal carcinoma. Healthy patients were
selected ad hoc from the same period (please refer to On-line
Appendix for additional details on patient selection). 1195 G 1. Comparison of spectral Hounsfield unit characteristics of n
al nonossified thyroid cartilage in healthy subjects and patients w
umors. A, Baseline characteristics of NOTC evaluated in 10 hea
ubjects is shown. For each patient, NOTC was evaluated with 9 R
n each side, corresponding to 18 ROIs total per patient, and 180 R
0 ROIs for each side of the NOTC/curve). There was no sign
ant difference in NOTC attenuation between the right and
des across the virtual monochromatic range of 40–140 keV
omparison of normal NOTC in healthy patients (right and
ombined; n 10, by using 180 ROIs) and normal or unaffec
OTC in the tumor group (n 27 by using 243 ROIs) C Poo the average ROI for each patient’s NOTC or tumor was given
equal weight when pooling data from multiple patients. Care was
taken to avoid overlap of the ROI with adjacent tissues or necrotic
parts of tumor to avoid volume averaging. All ROIs were placed
by an attending physician with fellowship training and 4 years’
postfellowship experience in neuroradiology and head and neck
radiology (R.F.). Additional information on the ROI analysis is
provided in the On-line Appendix. For each patient, the mean tumor and/or normal NOTC at-
tenuation was determined on the basis of the average Hounsfield
unit of the respective ROIs in that patient. Image noise was calcu-
lated as the SD in the ROI, and the average noise for each tumor or
NOTC was calculated by obtaining the average SD in their respec-
tive ROIs.17 Comparisons of tumor and NOTC attenuation were
performed by obtaining the average Hounsfield unit in all patients
across the VMI range (40–140 keV). MATERIALS AND METHODS
Patients Tumor and NOTC contrast-
to-noise ratios (CNRs) were calculated individually for each pa-
tient by using the following formula: CNR (Average Tumor
Attenuation Average Cartilage Attenuation)/Square Root
[Variance (Tumor) Variance (Cartilage)].17 In 3 patients with
HNSCC, the thyroid cartilage was completely ossified. In this sub-
group, the CNR calculation was performed by using the average
normal NOTC attenuation from the other 37 patients (27 with
HNSCC and 10 healthy patients). Statistical Analysis Results were reported as mean SD. Pooled average SHUAC
curves were generated from 40 to 140 keV, in 5-keV increments
for comparison of NOTC and tumor. For comparison of means
from 2 different groups, an unpaired 2-tailed t test was used. For
comparison of multiple (2) groups, 1-way ANOVA with the
Tukey multiple comparison test was used. Variance was calcu-
lated by using the standard formula: variance SD2. A P value
.05 was statistically significant. We used GraphPad Prism soft-
ware, Version 6.005, for statistical analysis (GraphPad Software,
San Diego, California). RESULTS We first evaluated the spectral Hounsfield unit characteristics of
normal NOTC in a group of 10 healthy patients (Fig 1A). The
NOTC attenuation was highest at 40 keV and progressively de-
creased on higher kiloelectron volt VMIs (Fig 1A). There was no
significant difference in the spectral Hounsfield unit characteris-
tics of the right compared with the left NOTC. We then evaluated
normal or unaffected NOTC in 30 patients with HNSCC (average
age, 72 years; range, 56–97 years; 15 men, 15 women). Their pri-
mary tumor sites are summarized in the Table. Of the patients
from the tumor group, 27 normal (or unaffected) NOTCs were
included. In 3 patients, the entire thyroid cartilage was ossified
and, therefore, was excluded from the analysis. There was no sig-
nificant difference in NOTC between healthy subjects and those
with normal or unaffected NOTC in the group of patients with
HNSCC (Fig 1B). Subgroup analysis of normal/unaffected NOTC
in the healthy patient group, patients with laryngeal cancer, those
with untreated primaries outside the larynx, and those with recur-
rent/metastatic tumors was also performed with 1-way ANOVA
with Tukey multiple comparison tests. There was no significant FIG 1. Comparison of spectral Hounsfield unit characteristics of nor-
mal nonossified thyroid cartilage in healthy subjects and patients with
tumors. A, Baseline characteristics of NOTC evaluated in 10 healthy
subjects is shown. For each patient, NOTC was evaluated with 9 ROIs
on each side, corresponding to 18 ROIs total per patient, and 180 ROIs
(90 ROIs for each side of the NOTC/curve). There was no signifi-
cant difference in NOTC attenuation between the right and left
sides across the virtual monochromatic range of 40–140 keV. B,
Comparison of normal NOTC in healthy patients (right and left
combined; n 10, by using 180 ROIs) and normal or unaffected
NOTC in the tumor group (n 27, by using 243 ROIs). C, Pooled
spectral Hounsfield unit curve demonstrating characteristics of
normal NOTC in the entire patient population (n 37). Values
shown are mean SD. difference in the attenuation of normal NOTC between any of the
groups, at any of the kiloelectron volts evaluated between 40 and
140 keV. The normal and unaffected NOTC spectral Hounsfield
unit attenuation measurements from healthy patients and those 1196 96
Forghani
Jun 2015
www.ajnr.org with tumor were combined and pooled from hereon for other
comparative analyses (Fig 1C). RESULTS metastatic tumors (n 8) were evaluated (Fig 2). All tumor sub-
groups had overall similar SHUAC characteristics (Fig 2). As ex-
pected, the attenuation of tumors was highest at 40-keV VMI, the
kiloelectron volt closest to the k-edge of iodine. Given the simi-
larity in their SHAUCs, the tumors were all combined and com-
pared with NOTC (Fig 3A). The SHUAC of tumors differed from
that of NOTC, with a statistically significant difference in the
mean attenuation of all tumors combined compared with NOTC
at all kiloelectron volts except 50, 55, and 60 keV (Fig 3A, P
.001). We next evaluated and compared the spectral attenuation
characteristics of HNSCC and NOTC. Untreated primaries from
the larynx (n 7), extralaryngeal sites (n 15), and recurrent/ FIG 2. Comparison of spectral Hounsfield unit characteristics of dif
ferent tumor subgroups: untreated larynx primaries (n 7), untreated
nonlarynx primaries (n 15), and recurrent/metastatic tumors (n 8
Note that the spectral Hounsfield unit attenuation curves of all the
HNSCC tumor groups follow a similar trend, with increased attenua
tion of enhancing tumor at lower kiloelectron volts and decreased
attenuation at higher kiloelectron volts. Values shown are mean SD At 70 keV, the VMI energy level typically considered to be
similar to that obtained with conventional single-energy CT,23
there was a small difference between mean tumor and NOTC
attenuation, with overlap between the 2 groups on the scatterplot
(Fig 3B). At the lowest extreme of the curve, at 40 keV, both tumor
and NOTC had the highest average attenuation. However, the
difference between tumor and NOTC was best seen on the higher
kiloelectron volt VMIs, due to a combination of differences in
attenuation and reduced variation (SD) of the measured values
in different patients (Fig 3A, -B). Indeed, in the groups evaluated
in this study, there was no overlap between individual mean
tumor and NOTC attenuation on VMIs reconstructed at 95
keV (Fig 3B). FIG 2. Comparison of spectral Hounsfield unit characteristics of dif-
ferent tumor subgroups: untreated larynx primaries (n 7), untreated
nonlarynx primaries (n 15), and recurrent/metastatic tumors (n 8). Note that the spectral Hounsfield unit attenuation curves of all the
HNSCC tumor groups follow a similar trend, with increased attenua-
tion of enhancing tumor at lower kiloelectron volts and decreased
attenuation at higher kiloelectron volts. Values shown are mean SD. AJNR Am J Neuroradiol 36:1194–200
Jun 2015
www.ajnr.org
1197 RESULTS quamous cell carcinoma compared with normal nonossified thyroid cartilage. y sites (n 30) compared with normal (or unaffected) NOTC (n 37; 27
p and 10 NOTCs from healthy patients). B, Scatterplot of individual tumor
TC densities at many VMIs but complete separation at high-energy VMIs. C,
olt VMIs demonstrating the higher absolute CNR at high-energy VMIs. D,
ding a case of hypopharyngeal tumor, n 23) primary sites. Three asterisks
cantly different. AJNR A
J N
di l 36 1194 200
J
2015
j
1197 FIG 3. Spectral Hounsfield unit characteristics of head and neck squamous cell carcinoma compared with normal nonossified thyroid cartilage. A, Spectral Hounsfield unit curve of HNSCC at different primary sites (n 30) compared with normal (or unaffected) NOTC (n 37; 27
normal/unaffected NOTCs from the patients with tumor group and 10 NOTCs from healthy patients). B, Scatterplot of individual tumor
densities at selected VMIs shows overlap between tumor and NOTC densities at many VMIs but complete separation at high-energy VMIs. C,
Contrast-to-noise analysis performed at different kiloelectron volt VMIs demonstrating the higher absolute CNR at high-energy VMIs. D,
Subgroup analysis of the laryngeal (n 7) and nonlaryngeal (including a case of hypopharyngeal tumor, n 23) primary sites. Three asterisks
denotes P .001; 4 asterisks denotes P .0001; and ns, not significantly different. AJNR Am J Neuroradiol 36:1194–200
Jun 2015
www.ajnr.org
1197 FIG 3. Spectral Hounsfield unit characteristics of head and neck squamous cell carcinoma compared with normal nonossified thyroid cartilage. A, Spectral Hounsfield unit curve of HNSCC at different primary sites (n 30) compared with normal (or unaffected) NOTC (n 37; 27
normal/unaffected NOTCs from the patients with tumor group and 10 NOTCs from healthy patients). B, Scatterplot of individual tumor
densities at selected VMIs shows overlap between tumor and NOTC densities at many VMIs but complete separation at high-energy VMIs. C,
Contrast-to-noise analysis performed at different kiloelectron volt VMIs demonstrating the higher absolute CNR at high-energy VMIs. D,
Subgroup analysis of the laryngeal (n 7) and nonlaryngeal (including a case of hypopharyngeal tumor, n 23) primary sites. Three asterisks
denotes P .001; 4 asterisks denotes P .0001; and ns, not significantly different. AJNR Am J Neuroradiol 36:1194–200
Jun 2015
www.ajnr.org
1197 FIG 4. Differences in attenuation of NOTC (arrows) and tumor (T) on different kiloelectron volt
VMIs. RESULTS Axial contrast-enhanced CT images are shown from a patient with a supraglottic squamous
cell carcinoma with the same section reconstructed as a virtual monochromatic images at 70, 40,
and 140 keV. A, Seventy-kiloelectron volt VMI shows tumor abutting the inner surface of the
right NOTC. B, Forty-kiloelectron volt VMI shows greater attenuation of the tumor than on
the 70-keV VMI due to iodine content, increased contrast between tumor and NOTC, and
somewhat better depiction of tumor-NOTC interface. C, One hundred forty–kiloelectron
volt VMI shows suppression of tumor attenuation but preserved high attenuation in the
NOTC. Note the qualitative contrast improvement with clear distinction of tumor-NOTC
interface. Subgroup analysis of the laryngeal
(n 7) primaries demonstrated similar
trends in SHUAC, with persistent clear
separation from the normal NOTC
curve in the high kiloelectron volt range
(Fig 3D). Subgroup analysis comparing
NOTC with the untreated laryngeal pri-
maries, untreated primaries outside the
larynx, and recurrent/metastatic tumors
also demonstrated a statistically signifi-
cant difference between NOTC and all
tumor
subgroups
on
VMIs
recon-
structed at 70 KeV (P .0001, 1-way
ANOVA), with the greatest difference at
of 95 KeV. FIG 4. Differences in attenuation of NOTC (arrows) and tumor (T) on different kiloelectron volt
VMIs. Axial contrast-enhanced CT images are shown from a patient with a supraglottic squamous
cell carcinoma with the same section reconstructed as a virtual monochromatic images at 70, 40,
and 140 keV. A, Seventy-kiloelectron volt VMI shows tumor abutting the inner surface of the
right NOTC. B, Forty-kiloelectron volt VMI shows greater attenuation of the tumor than on
the 70-keV VMI due to iodine content, increased contrast between tumor and NOTC, and
somewhat better depiction of tumor-NOTC interface. C, One hundred forty–kiloelectron
volt VMI shows suppression of tumor attenuation but preserved high attenuation in the
NOTC. Note the qualitative contrast improvement with clear distinction of tumor-NOTC
interface. We also calculated the CNR to factor
in differences in noise levels at different
VMI energy levels. As in the previous
observations, the absolute CNR was
highest on high kiloelectron volt images
(Fig 3C). Note that the negative values in
Fig 3C indicate that tumor has a lower
attenuation than NOTC at these kilo-
electron volts. Therefore, tumor inva-
sion of NOTC would be expected to ap-
pear as a low-attenuation defect in the
otherwise high-attenuation NOTC (Figs
4 and 5). FIG 5. RESULTS Quantitative spectral Hounsfield unit attenuation characterization of tumor and NOTC in
a patient with pathologically proved tumor invasion into the thyroid cartilage. VMIs recon-
structed at 40 keV (A) and 140 keV (B) demonstrate tumor invasion into the anterior left thyroid
cartilage (white arrows). Note variable ossification of the left thyroid cartilage and minimal focal
nonossification of the right thyroid cartilage. On the 140-keV VMI, attenuation due to invasion of
the left thyroid cartilage (white arrows) is suppressed, appearing as a defect, compared with the
normal ipsilateral NOTC and contralateral NOTC (red arrows). C and D, An example of quantita-
tive analysis is shown, demonstrating individual spectral Hounsfield unit attenuation curves for
different ROIs. Note the differences in spectral attenuation characteristics of tumor (T) com-
pared with normal ipsilateral and contralateral NOTC. The spectral curve shows clear attenuation
separation in the higher kiloelectron volt range. Please note that the curves shown in this figure
are those for individual ROIs. In earlier figures, the average from multiple ROIs (at least 9) per
structure, per patient, was used to calculate pooled mean attenuation for each group or sub-
group (in addition, areas of invasion were not included in the earlier pooled analysis). 1198
Forghani
Jun 2015
www ajnr org 1198
Forghani
Jun 2015
www.ajnr.org ACKNOWLEDGMENTS We thank Veronika Glyudza for her assistance in data preparation
and processing. Disclosures: Reza Forghani—UNRELATED: Consultancy: Biogen Idec, Colle`ge des
Me´decins du Que´bec, Comments: no relation to submitted work; one time hono-
rarium for the “Neuroradiology Scientific Exchange Program: Focus on the Role of
MRI in the Detection, Diagnosis and Monitoring of Natalizumab-Associated Progres-
sive Multifocal Leukoencephalopathy in Patients with Multiple Sclerosis,” Montreal,
Quebec, Canada, February 22, 2014; expert consultant for Colle`ge des Me´decins du
Que´bec (Telemedicine Committee, quality assurance); Expert Testimony: Colle`ge
des Me´decins du Que´bec, Comments: quality assurance reviews (no relation to
current work); Payment for Lectures (including service on Speakers Bureaus): no
relation to submitted work; “Peer Review for Departmental QA and Audits: Essentials
of a Successful Program, Benchmarks for Evaluation, and Challenges,” Ontario Asso-
ciation of Radiologists Continuing Medical Education Peer Review Course, Ontario
Bar Association, Toronto, Ontario, Canada, June 7, 2014; “Sinus Anatomy: Normal and
Postoperative,” Ontario Association of Radiologists Continuing Medical Education
Head and Neck Imaging Course, Part I, Ontario Bar Association, Toronto, Ontario,
Canada, May 24, 2014; Visiting Professor, McMaster University Health Sciences Cen-
ter; Radiology Grand Rounds, St. Joseph’s Healthcare Hamilton (“Applications of
Diffusion-Weighted MR Imaging in the Evaluation of Acute Ischemia and Non-Isch-
emic Neurological Disorders”), Hamilton, Ontario, Canada, January 22, 2013; Stock/
Stock Options: Real Time Medical Inc, Comments: no relation to submitted work;
member, Medical and Quality Assurance Committee. Mark Levental—UNRELATED:
Consultancy: Biogen Idec; Payment for Lectures (including service on Speakers
Bureaus): Biogen Idec, Comments: member of speakers bureau. Rajiv Gupta—UN-
RELATED: Board Membership: Actelion, Comments: advising the company on the
use of imaging in their drug trials; Grants/Grants Pending: Siemens,* Comments:
research grant to the institution; Travel/Accommodations/Meeting Expenses Un-
related to Activities Listed: Siemens, Comments: travel support for a symposium
organized by Siemens. Hugh D. Curtin—UNRELATED: Royalties: Elsevier, Comments:
royalties for textbook, not related to this article. *Money paid to the institution. Compared with iodine overlay maps, high kiloelectron volt–
reconstructed VMIs are similar to standard sequences to which
radiologists are accustomed, possibly providing an advantage for
implementation and user acceptance. DISCUSSION
d Accurate determination of thyroid carti-
lage invasion is important for proper
staging and treatment planning of laryn-
geal and hypopharyngeal cancers.1-8
Evaluation of thyroid cartilage invasion
on imaging remains a challenge because
of variable ossification and appearance
of thyroid cartilage and similarities in
attenuation of tumor and NOTC on
CT.1,2,10,11 While tumor preferentially
invades the ossified part of the cartilage,
the similarity in appearance of NOTC
and tumor can make definitive assess-
ment for invasion challenging in cases in
which tumor abuts the nonossified part
of thyroid cartilage. Clear distinction of
invasive tumor and focal nonossifica-
tion of the cartilage may not be possible. FIG 5. Quantitative spectral Hounsfield unit attenuation characterization of tumor and NOTC in
a patient with pathologically proved tumor invasion into the thyroid cartilage. VMIs recon-
structed at 40 keV (A) and 140 keV (B) demonstrate tumor invasion into the anterior left thyroid
cartilage (white arrows). Note variable ossification of the left thyroid cartilage and minimal focal
nonossification of the right thyroid cartilage. On the 140-keV VMI, attenuation due to invasion of
the left thyroid cartilage (white arrows) is suppressed, appearing as a defect, compared with the
normal ipsilateral NOTC and contralateral NOTC (red arrows). C and D, An example of quantita-
tive analysis is shown, demonstrating individual spectral Hounsfield unit attenuation curves for
different ROIs. Note the differences in spectral attenuation characteristics of tumor (T) com-
pared with normal ipsilateral and contralateral NOTC. The spectral curve shows clear attenuation
separation in the higher kiloelectron volt range. Please note that the curves shown in this figure
are those for individual ROIs. In earlier figures, the average from multiple ROIs (at least 9) per
structure, per patient, was used to calculate pooled mean attenuation for each group or sub-
group (in addition, areas of invasion were not included in the earlier pooled analysis). Kuno et al22 demonstrated that DECT
iodine overlay images improved the
specificity of detection of laryngeal car-
tilage invasion. In our investigation, we
compared the spectral Hounsfield unit
characteristics of tumor and NOTC by
using a single-source DECT with rapid
kiloelectron volt switching to determine
the utility of VMIs reconstructed at var- 1198 1198
Forghani
Jun 2015
www.ajnr.org ious kiloelectron volt levels for distinguishing tumor from NOTC. Our study expands on observations by Kuno et al that DECT can
be helpful in the evaluation of laryngeal cartilage in patients with
HNSCC. CONCLUSIONS HNSCC has different spectral Hounsfield unit attenuation char-
acteristics with significantly different attenuation on VMIs of 95
keV compared with nonossified thyroid cartilage. Therefore,
DECT has the potential to improve accuracy for distinguishing
tumor and NOTC and to improve evaluation of cartilage invasion
by laryngeal cancer. On the other hand, there were significant differences in atten-
uation at either extreme of the VMI energy curve, with the dis-
tinction between tumor and NOTC best achieved on VMIs of
95 keV. On high kiloelectron volt VMIs, iodine attenuation in
enhancing tumor is partially suppressed, whereas the normal
NOTC retains a relatively high and fairly uniform attenuation and
would therefore be distinct from adjacent tumor (Fig 4). Against
the high-attenuation background of NOTC, tumor would be ex-
pected to appear as a relatively low-attenuation defect that stands
out from the normal thyroid cartilage (Fig 5). Normal NOTC has
uniform attenuation without gaps or defects.24 On the basis of the
results of our study, one would expect that VMIs may be used
qualitatively to assess NOTC integrity (Figs 4 and 5). In cases
where there is ambiguity, supplemental evaluation with quantita-
tive ROI analysis and SHUAC analysis may also be helpful. A
potential example of such application, demonstrating individual
ROI curves, is shown in Fig 5. On the basis of the observations in
this study, we believe that future investigations directly evaluating
applications of high-energy VMI and SHUAC for thyroid carti-
lage invasion are warranted. Because many patients without thy-
roid cartilage invasion or with minor invasion may not be treated
surgically, such studies will be designed to correlate imaging find-
ings with long-term patient outcome rather than on the basis of
histopathologic correlation alone. DISCUSSION
d In our study, we evaluated another aspect of DECT,
VMIs reconstructed at different kiloelectron volt energy levels, to
characterize and compare HNSCC and unaffected NOTC. the different tumor subgroups, all of the tumor groups had simi-
lar spectral attenuation characteristics (Fig 2). Furthermore, sim-
ilar differences in NOTC and tumor attenuation with the greatest
difference on high kiloelectron volt VMIs were observed when
NOTC was compared with either the entire group of 30 tumors
and specific subgroups. Although in this investigation we did not directly evaluate thy-
roid cartilage invasion, the observations in this study are a step
toward application of VMIs and SHUAC analysis for assessment
of NOTC and proceeding to studies evaluating NOTC invasion. We demonstrate that HNSCC has a very different spectral
Hounsfield unit attenuation curve than normal NOTC. Although
there was some difference in mean attenuation between NOTC
and tumor at 70 keV, the VMI energy level similar to that of a
standard single-energy CT acquisition,23 the difference was small
and there was overlap between individual tumor and NOTC at-
tenuation. This finding reflects the challenges that can be encoun-
tered in distinguishing NOTC from tumor on conventional CT. Limitations of this study include the retrospective design and
small number of cases. In addition, there was no pathologic con-
firmation of uninvaded NOTC. Nonetheless, our study demon-
strates clear qualitative and quantitative differences in spectral
Hounsfield unit attenuation curves of HNSCC compared with
NOTC. We believe that our investigation and that by Kuno et al22
provide the basis for future, ideally prospective, studies to evalu-
ate the advantages of DECT, including high kiloelectron volt
VMIs, for detecting thyroid cartilage invasion and predicting pa-
tient outcome. ACKNOWLEDGMENTS In addition, high kiloelec-
tron volt VMIs can result in decreased artifacts associated with
metallic implants and other materials.25,26 At this time, both
high-energy kiloelectron volt VMIs and iodine overlay maps are
likely to be useful for increasing the accuracy of CT for determi-
nation of laryngeal cartilage invasion, and a comparison of the 2
and evaluation of potential complementary application in thyroid
cartilage assessment is an interesting topic for future research. AJNR Am J Neuroradiol 36:1194–200
Jun 2015
www.ajnr.org
11 REFERENCES 1. Hermans R. Staging of laryngeal and hypopharyngeal cancer: value
of imaging studies. Eur Radiol 2006;16:2386–400 1. Hermans R. Staging of laryngeal and hypopharyngeal cancer: value
of imaging studies. Eur Radiol 2006;16:2386–400 Because this work is a general characterization of HNSCC, we
used both primary laryngeal tumors and tumors outside the lar-
ynx. In addition, we evaluated recurrent/metastatic tumors. Al-
though there were small differences in mean attenuation among g
g
2. Kuno H, Onaya H, Fujii S, et al. Primary staging of laryngeal and
hypopharyngeal cancer: CT, MR imaging and dual-energy CT. Eur J
Radiol 2014;83:e23–35 1199 3. Ferlito A, Silver CE, Howard DJ, et al. The role of partial laryngeal
resection in current management of laryngeal cancer: a collective
review. Acta Otolaryngol 2000;120:456–65 reconstruction of dual-energy unenhanced head CT at 65–75 keV
maximizes image quality compared with conventional polychro-
matic CT. Radiology 2013;266:318–25 y g
4. Hartl DM, Landry G, Hans S, et al. Organ preservation surgery for
laryngeal squamous cell carcinoma: low incidence of thyroid carti-
lage invasion. Laryngoscope 2010;120:1173–76 18. Tawfik AM, Kerl JM, Bauer RW, et al. Dual-energy CT of head and
neck cancer: average weighting of low- and high-voltage acquisi-
tions to improve lesion delineation and image quality: initial clini-
cal experience. Invest Radiol 2012;47:306–11 g
y g
p
5. Jenckel F, Knecht R. State of the art in the treatment of laryngeal
cancer. Anticancer Res 2013;33:4701–10 19. Vogl TJ, Schulz B, Bauer RW, et al. Dual-energy CT applications in
head and neck imaging. AJR Am J Roentgenol 2012;199:S34–39 6. Knab BR, Salama JK, Solanki A, et al. Functional organ preservation
with definitive chemoradiotherapy for T4 laryngeal squamous cell
carcinoma. Ann Oncol 2008;19:1650–54 20. Tawfik AM, Kerl JM, Razek AA, et al. Image quality and radiation
dose of dual-energy CT of the head and neck compared with a
standard 120-kVp acquisition. AJNR Am J Neuroradiol 2011;32:
1994–99 7. Lefebvre JL. Larynx preservation. Curr Opin Oncol 2012;24:218–22 8. Edge SB, Byrd DR, Compton CC, et al. AJCC Cancer Staging Manual. New York: Springer-Verlag; 2010 21. Srinivasan A, Parker RA, Manjunathan A, et al. Differentiation of
benignandmalignantneckpathologies:preliminaryexperienceus-
ing spectral computed tomography. J Comput Assist Tomogr 2013;
37:666–72 9. Becker M, Zbaren P, Delavelle J, et al. Neoplastic invasion of the
laryngeal cartilage: reassessment of criteria for diagnosis at CT. Ra-
diology 1997;203:521–32 gy
10. Archer CR, Yeager VL. Evaluation of laryngeal cartilages by com-
puted tomography. 1200
Forghani
Jun 2015
www.ajnr.org REFERENCES J Comput Assist Tomogr 1979;3:604–11 22. Kuno H, Onaya H, Iwata R, et al. Evaluation of cartilage invasion by
laryngeal and hypopharyngeal squamous cell carcinoma with dual-
energy CT. Radiology 2012;265:488–96 11. Mafee MF, Schild JA, Michael AS, et al. Cartilage involvement in
laryngeal carcinoma: correlation of CT and pathologic macrosec-
tion studies. J Comput Assist Tomogr 1984;8:969–73 23. Patel BN, Thomas JV, Lockhart ME, et al. Single-source dual-energy
spectral multidetector CT of pancreatic adenocarcinoma: optimi-
zation of energy level viewing significantly increases lesion con-
trast. Clin Radiol 2013;68:148–54 12. Becker M. Neoplastic invasion of laryngeal cartilage: radiologic di-
agnosis and therapeutic implications. Eur J Radiol 2000;33:216–29 g
13. Beitler JJ, Muller S, Grist WJ, et al. Prognostic accuracy of computed
tomographyfindingsforpatientswithlaryngealcancerundergoing
laryngectomy. J Clin Oncol 2010;28:2318–22 24. Dadfar N, Seyyedi M, Forghani R, et al. Computed tomography ap-
pearance of normal nonossified thyroid cartilage: implication for
tumor invasion diagnosis. J Comput Assist Tomogr 2015;39:240–43 14. Zba¨re P, Becker M, Lang H. Pretherapeutic staging of laryngeal
carcinoma: clinical findings, computed tomography, and magnetic
resonance imaging compared with histopathology. Cancer 1996;77:
1263–73 g
g
25. Srinivasan A, Hoeffner E, Ibrahim M, et al. Utility of dual-energy CT
virtual keV monochromatic series for the assessment of spinal
transpedicular hardware-bone interface. AJR Am J Roentgenol
2013;201:878–83 15. Johnson TR, Fink C, Scho¨nberg SO, et al, eds. Dual Energy CT in
Clinical Practice. Berlin: Springer-Verlag; 2011 26. Stolzmann P, Winklhofer S, Schwendener N, et al. Monoenergetic
computedtomographyreconstructionsreducebeamhardeningar-
tifacts from dental restorations. Forensic Sci Med Pathol 2013;9:
327–32 g
g
16. Johnson TR. Dual-energy CT: general principles. AJR Am J Roent-
genol 2012;199:S3–8 16. Johnson TR. Dual-energy CT: general principles. AJR Am J Roent-
genol 2012;199:S3–8 g
17. Pomerantz SR, Kamalian S, Zhang D, et al. Virtual monochromatic 17. Pomerantz SR, Kamalian S, Zhang D, et al. Virtual monochromatic 1200
Forghani
Jun 2015
www.ajnr.org 1200
|
https://openalex.org/W2767185028
|
https://hal-ensta-paris.archives-ouvertes.fr/hal-01622332/document
|
English
| null |
Long-lived laser-induced arc discharges for energy channeling applications
|
Scientific reports
| 2,017
|
cc-by
| 8,135
|
To cite this version: Guillaume Point, Léonid Arantchouk, Emmanuelle Thouin, Jérôme Carbonnel, André Mysyrowicz,
et al.. Long-lived laser-induced arc discharges for energy channeling applications. Scientific Reports,
2017, 7 (1), pp.13801. 10.1038/s41598-017-14054-z. hal-01622332 Long-lived laser-induced arc
discharges for energy channeling
applications Received: 12 April 2017
Accepted: 6 October 2017
Published: xx xx xxxx Received: 12 April 2017
Accepted: 6 October 2017
Published: xx xx xxxx Guillaume Point1,2, Leonid Arantchouk1,3, Emmanuelle Thouin1, Jérôme Carbonnel1,
André Mysyrowicz1 & Aurélien Houard 1 Guillaume Point1,2, Leonid Arantchouk1,3, Emmanuelle Thouin1, Jérôme Carbonnel1,
André Mysyrowicz1 & Aurélien Houard 1 Laser filamentation offers a promising way for the remote handling of large electrical power in the form
of guided arc discharges. We here report that it is possible to increase by several orders of magnitude
the lifetime of straight plasma channels from filamentation-guided sparks in atmospheric air. A 30 ms
lifetime can be reached using a low-intensity, 100 mA current pulse. Stability of the plasma shape is
maintained over such a timescale through a continuous Joule heating from the current. This paves the
way for applications based on the generation of straight, long duration plasma channels, like virtual
plasma antennas or contactless transfer of electric energy. Laser filamentation is a nonlinear optical phenomena that was discovered in the early days of the laser era, when
damage tracks and thin fluorescent channels were witnessed in transparent condensed matter through which a
powerful laser pulse propagated1,2. But it is only after the chirped pulse amplification technique was devised3 that
filamentation could be witnessed in gases4.h i
This propagation regime results from the dynamic competition between the self-induced collapse of a power-
ful laser pulse due to the optical Kerr effect, on the one hand, and diffraction, group velocity dispersion, nonlinear
absorption of the laser energy and photoionization-induced plasma defocusing, on the other hand. This yields
the formation of thin and long channels - or filaments - in which the pulse is able to maintain a very high intensity
seemingly without suffering from diffraction5–9.i ff
A very interesting property of filaments is that while propagating in this regime, a laser pulse deposits a sig-
nificant part of its energy in the propagation medium over the whole filament length. This nonlinear energy
absorption occurs chiefly through high-field ionization, but also from rotational stimulated Raman scattering10. After a nanosecond-scale thermalization, this fast energy deposition is eventually converted into heat and leads to
the formation and subsequent hydrodynamic expansion of a hot air cylinder along the filament, leaving a central
air channel with reduced density11–17. HAL Id: hal-01622332
https://ensta-paris.hal.science/hal-01622332v1
Submitted on 24 Nov 2017 L’archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d’enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés. HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers. www.nature.com/scientificreports www.nature.com/scientificreports Received: 12 April 2017
Accepted: 6 October 2017
Published: xx xx xxxx Long-lived laser-induced arc
discharges for energy channeling
applications This in turn reduces the dielectric strength of air, meaning that a spark dis-
charge can be induced at a voltage lower than the breakdown voltage by connecting two charged electrodes with
filaments12,18. As such, laser filamentation was shown to be able to trigger and guide long sparks18–21, guide corona
discharges22, and even deviate discharges from their natural path23. Recently, Clerici et al. also demonstrated
control of curved spark trajectories by means of Airy laser beams instead of the widely used Gaussian beam24. Théberge and co-authors also showed that meter-sized, milliseconds duration guided discharges can successfully
be developed using a double-circuit scheme25,26. p
g
Filamentation-guided discharges have several interesting applications currently under active development. First, such straight and precisely controlled plasma columns can be used as a substitute for radio-frequency (RF)
metallic antennas, sporting superior reconfigurability and stealth capabilities27,28. Laser-induced discharges have
also long been envisioned as a means to transfer high intensity electrical energy. A filament lightning rod could
be used to protect sensitive facilities by triggering the inception of downward leaders from lightning clouds29 or
intercepting naturally-generated downward leaders before they reach the ground23,30,31. They can also be used to
channel electrical energy along a well-controlled path, with several pending technologies like the design of sturdy
and reliable closing switches with a very low jitter32 or even a replacement for the pantograph on trains, leading to
the suppression of mechanical friction with overhead power lines33,34. 1Laboratoire d’Optique Appliquée, ENSTA ParisTech, CNRS, Ecole Polytechnique, Université Paris-Saclay, 828
boulevard des Maréchaux, 91762, Palaiseau cedex, France. 2ONERA-CP, Chemin de la Hunière et des Joncherettes,
91123, Palaiseau cedex, France. 3Laboratoire de Physique des Plasmas, CNRS, Ecole Polytechnique, Université
Paris-Saclay, route de Saclay, 91128, Palaiseau cedex, France. Correspondence and requests for materials should be
addressed to G.P. (email: guillaume.point@onera.fr) SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z 1 www.nature.com/scientificreports/ www.nature.com/scientificreports/ Figure 1. (a) Schematic description of the double circuit scheme. (b) Recorded waveforms for currents i1 and i2,
clearly showing initial high-frequency and long term low-frequency oscillations. Figure 1. (a) Schematic description of the double circuit scheme. (b) Recorded waveforms for currents i1 and i2,
clearly showing initial high-frequency and long term low-frequency oscillations. However several problems currently plague the development of such applications. Results Long duration, high current filamentation-guided discharges. The generation of millisecond-dura-
tion, 100 A sparks was done using a slightly modified version of the double-circuit scheme already used by
Arantchouk et al.25. This scheme was built around a filamentation-triggered Marx generator as the high-voltage
source. Using a single laser pulse, it has previously been demonstrated that it was possible to trigger both the
generator, and a guided discharge at its output up to 21 cm long with a 180 kV output voltage36. In the present
experiment the output voltage was reduced to 100 kV for practical purposes, while the gap was shortened to 85
mm to keep discharge jitter at a reasonable level. The double circuit is depicted in Fig. 1(a). It consists in two
entangled RLC circuits. When gap breakdown occurs, the low energy (10 J) 5-stage Marx generator, starts to
discharge in the first (R2L2C2) circuit provided that L2 ≪ L1. It results in damped sinusoidal oscillations at the high
frequency fHF = 156 kHz. Once the spark is established, the capacitor C2, initially charged to U2 = 20 kV for a 32
J total energy, starts to discharge through the plasma. By carefully choosing the value of L1 with respect to the
Marx generator’s impedance, almost no return current goes to the generator. This secondary (R2L1L2C2) circuit is
characterized by current oscillations with a much lower frequency fLF = 4 kHz. By keeping the ballast resistor R2
at a small value (10 Ω), current damping is low enough so that it oscillates for more than 1 ms (see Fig. 1(b)). We
can see that |
| ≈|
|
i t
i t
( )
( )
1
2
in this regime, showing the absence of return current in the Marx.i Guided discharges were characterized using three main diagnostics: electron and neutral air density profiles
were recorded simultaneously by means of a two-color interferometer37. A high speed camera was used to record
time-resolved pictures of the plasma emission in the visible range for the whole duration of a given discharge. Finally current viewing resistors (shunts) were used to record the time evolution of the discharge current. Results from the two-color interferometry are presented in Fig. 2. The simple study of interferograms
(Fig. Long-lived laser-induced arc
discharges for energy channeling
applications Taking the example of
the plasma antenna28, the performance of these technologies directly depends on the ability of the discharge
plasma to remain at the required conductivity level for as long as possible. A second problem, which is expected
to become more and more important as the plasma lifetime is increased, is to be able to preserve the shape of the
plasma column for the required time.i p
q
We have previously shown that the temporal evolution of electron density in filamentation-guided discharges
is dictated by the discharge current waveform when the current time evolution is slow35. From this finding we
devised two different techniques to increase the plasma lifetime to a millisecond timescale, that we demonstrate
in this Article: •
If a high electron density plasma is required, an oscillating current with high amplitude and low damping is
best adapted. This scheme was tested using a homemade filament-triggered, 180 kV Marx generator36 to gen-
erate a 10 cm spark with ~10 μs lifetime before injecting ~100 A AC current in the resulting plasma to sustain
it over a millisecond timescale. •
If a high electron density plasma is required, an oscillating current with high amplitude and low damping is
best adapted. This scheme was tested using a homemade filament-triggered, 180 kV Marx generator36 to gen-
erate a 10 cm spark with ~10 μs lifetime before injecting ~100 A AC current in the resulting plasma to sustain
it over a millisecond timescale. •
Conversely, when a lower electron density is required, a low-amplitude, long-lasting monopolar current pulse
is the ideal solution. This scheme was tested using a very compact, strongly-damped 30 kV RC circuit deliv-
ering a ~10 ms, 100 mA current pulse over a 10 cm gap. •
Conversely, when a lower electron density is required, a low-amplitude, long-lasting monopolar current pulse
is the ideal solution. This scheme was tested using a very compact, strongly-damped 30 kV RC circuit deliv-
ering a ~10 ms, 100 mA current pulse over a 10 cm gap. We also show that in both cases the discharge spatial shape can be preserved over such long timescales through
the continuous Joule heating of the plasma by the residual current. SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z Results 2(a)) already brings useful information about the discharge physics, showing the formation of a steep optical
index gradient propagating outwards at early times, leaving a perturbed cylinder at the center. This can be quite
easily interpreted at the generation of a shock wave due to the sudden heating from the deposited energy in the
plasma, which expels matter from the center of the discharge and leaves a tube of low density.itti When looking at neutral and electron density radial profiles after the shock has left the field of view (Fig. 2(b)),
one can see that free electrons are concentrated in the form of a narrow peak with a ~500 μm half-width at
half-maximum (HWHM). A secondary ring is also observed at a radial position corresponding to the neutral
channel boundary. However, one must be cautious about the reality of this peak at the edge of the low density
channel, because its position corresponds to sharp changes in the interferograms and could therefore correspond
to a measurement artifact. The maximum electron density reached is on the order of 1023 m−3. In the case of SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z 2 www.nature.com/scientificreports/ Figure 2. Two-color interferometry results on long-lived discharges. (a) Example of interferograms recorded
at delay 2 μs (left) and 120 μs (right) in the single shot regime, showing the formation of a shock wave and
the expansion of the subsequent channel. (b) Radial profiles of electron density (blue) and of neutral density
(red) at delay 280 μs, showing the formation of a large channel with a strongly depleted neutral density while
the plasma remains confined at the center in the form of a much narrower cylinder. Negative densities come
from measurement uncertainties estimated at 4 × 1022 m−3 for electrons and 1024 m−3 for neutrals37. (c) Time
evolution of on-axis electron density (blue circles) and of the discharge current (red solid curve). The electron
detection threshold (green solid line) is estimated to be around 4 × 1022 m−3
37. Electron density initially quickly
decays, but starts oscillating with the low-frequency current at longer times. Blue arrows indicate times at which
measurements could not detect free electrons. Results The electron
detection threshold (green solid line) is estimated to be around 4 × 1022 m−3
37. Electron density initially quickly
decays, but starts oscillating with the low-frequency current at longer times. Blue arrows indicate times at which
measurements could not detect free electrons. (d) Time evolution of the neutral channel radius (blue circles)
and of the total quantity of lacking neutral molecules with respect to air in standard pressure and temperature
conditions (red squares), showing the channel is still expanding and remains at a low density even after a delay
900 μs. standard density air, this would correspond to a ionization ratio of less than 1%. However, one can see that the
corresponding neutral profile shows a much larger channel with a ~4 mm HWHM and a quasi-depleted density. Given the resolution of our instrument on the order of 1024 m−3 37, we therefore estimate that the residual air
density in the underdense channel is below ~10% of the air density in normal pressure and temperature condi-
tions n0 = 2.47 × 1025 m−3. Consequently the real ionization ratio of the discharge plasma is at least one order of
magnitude higher than previously estimated. It is even possible that the central plasma column could actually be
fully ionized. y
Figure 2(c) shows the time evolution of on-axis electron density, compared to that of the discharge current. At
early times, when the current evolves in the high frequency regime, the electron density decays relatively quickly,
almost reaching the detection threshold by 10 μs. However at later times, in the low-frequency regime, it is back
to a level ~1023 m−3. Interestingly, while the measurements performed at times corresponding to a local current
extremum yield electron profiles, the electron density falls below the detection threshold when the current is near
0. It means that electron density starts to oscillate at twice the current frequency, as it was predicted in the case of
a low frequency AC discharge current35. q
y
g
Hint of this behavior was given by the dependence of plasma luminescence on the square of the current as
recorded in reference25,26, but our measurement is the first to show a direct dependence of the plasma electron
density on the discharge current in the AC regime. Therefore the design of specific current waveforms could ena-
ble one to precisely control the plasma density and reach even longer discharge lifetimes. Results (d) Time evolution of the neutral channel radius (blue circles)
and of the total quantity of lacking neutral molecules with respect to air in standard pressure and temperature
conditions (red squares), showing the channel is still expanding and remains at a low density even after a delay
900 μs. color interferometry results on long-lived discharges. (a) Example of interferograms recorded t Figure 2. Two-color interferometry results on long-lived discharges. (a) Example of interferograms recorded
at delay 2 μs (left) and 120 μs (right) in the single shot regime, showing the formation of a shock wave and
the expansion of the subsequent channel. (b) Radial profiles of electron density (blue) and of neutral density
(red) at delay 280 μs, showing the formation of a large channel with a strongly depleted neutral density while
the plasma remains confined at the center in the form of a much narrower cylinder. Negative densities come
from measurement uncertainties estimated at 4 × 1022 m−3 for electrons and 1024 m−3 for neutrals37. (c) Time
evolution of on-axis electron density (blue circles) and of the discharge current (red solid curve). The electron
detection threshold (green solid line) is estimated to be around 4 × 1022 m−3
37. Electron density initially quickly
decays, but starts oscillating with the low-frequency current at longer times. Blue arrows indicate times at which
measurements could not detect free electrons. (d) Time evolution of the neutral channel radius (blue circles)
and of the total quantity of lacking neutral molecules with respect to air in standard pressure and temperature
conditions (red squares), showing the channel is still expanding and remains at a low density even after a delay
900 μs. Figure 2. Two-color interferometry results on long-lived discharges. (a) Example of interferograms recorded
at delay 2 μs (left) and 120 μs (right) in the single shot regime, showing the formation of a shock wave and
the expansion of the subsequent channel. (b) Radial profiles of electron density (blue) and of neutral density
(red) at delay 280 μs, showing the formation of a large channel with a strongly depleted neutral density while
the plasma remains confined at the center in the form of a much narrower cylinder. Negative densities come
from measurement uncertainties estimated at 4 × 1022 m−3 for electrons and 1024 m−3 for neutrals37. (c) Time
evolution of on-axis electron density (blue circles) and of the discharge current (red solid curve). SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z Results 2(b)), σp is on the
order of 104 S · m−1. The pressure in the plasma is expected to be back to atmospheric pressure after a few hundred
microseconds38. In this case temperature can be derived from plasma conductivity by computing transport coef-
ficients of high temperature air39. This leads to a plasma temperature of ~13000 K. Since p ~ patm ≈ 105 Pa, we can
also estimate the air density in the plasma using the ideal gas law: =
∼
. −
n
p
k T
10
m
(5)
n
B
23
3 (5) As the electronic Debye length in the plasma is estimated at ~10 nm for an electron density of 1023 m−3 and a
temperature of 10 kK, the discharge plasma must respect quasi-neutrality. Consequently, as the density of heavy
species is estimated to be the same as electron density, this confirms our early assumption that the discharge
plasma has an actual ionization ratio close to 1.hi The oscillatory behavior observed with electron density is not shared by the neutral density profile (Fig. 2(d)). Indeed the underdense channel front keeps propagating in time, eventually reaching a 6 mm HWHM by 900 μs. Another precious information comes from the time evolution of the channel depth, here evaluated in terms of
neutral molecule deficit over the whole discharge by integrating the density profile:
∫
∫
π
=
−
n
n r z r
r z
neutral deficit
2
(
( ,
)) d d ,
(6)
A
L
n
0
0
gap
(6) where
A
is the Avogadro number. As seen on the graph, the depletion also keeps increasing. It means that the
global hydrodynamic flux is still directed towards the outside of the channel at this time, driven by the continuous
energy deposition from the Joule heating in the plasma. As long as this heating remains sufficient to displace
neutrals outside of the discharge channel, hydrodynamic instabilities at the boundary are prevented from form-
ing40. The discharge is therefore inherently stable.hh h
This analysis can be strengthened using results from the fast camera imaging of the discharge. This study was
performed by recording images with a 288 kHz camera repetition rate and a 293 ns exposure time. As displayed in
Fig. 3(b), the plasma luminescence evolves strongly in time, experiencing oscillations at nearly twice the discharge
current frequency, an effect already identified in previous studies25,26. Results More importantly, as seen on the discharge
pictures (Fig. 3(a)), the shape of the discharge remains stable with only marginal distortion throughout the whole
discharge life. To better quantify this parameter, we make use of the normalized root mean square distortion
(nRMSD), defined in the Methods section. A null nRMSD corresponds to a discharge keeping the same path for
the whole discharge duration, while a nRMSD of 1 corresponds to a discharge where the amplitude of transverse
distortions is on the order of the gap length. As seen in Fig. 3(c), the nRMSD of guided discharges remains at a
very low level for the whole duration of the discharge on the order of 1%. However, it steadily increases in time
in a fashion similar to that of the current envelope, and experiences small surges when the current approaches 0. This confirms the fundamental influence of the discharge current on the discharge stability through the continu-
ous Joule heating of the discharge channel. Long duration, low current filamentation-guided discharges. Long-lived, low current discharges
were investigated using a much simpler setup than previously. It consists in a simple RC circuit (Fig. 4(a)), in
which the capacitor is charged to a voltage U0 before filaments are used to close the gap and generate a guided
discharge. The goal here was to initiate a very long current pulse with a low amplitude, leading us to use a very
high ballast resistor of 230 kΩ. In order to extend the gap to 85 mm, like in the previous case, with a voltage as low
as 28 kV, we make use of an axicon lens instead of a spherical lens to generate laser filaments, a technique which
proved able to decrease the breakdown voltage of air by one order of magnitude24. This result represents an even
higher increase in discharge length than was observed with AC high voltage (~400%)41,42. g
g
g
g
g
Since insulation constraints are much lower than in the case of the Marx generator, it is possible to continu-
ously record the gap voltage using a simple high-voltage probe. This enables us to track the time evolution of the
plasma resistance. As seen in Fig. Results Surprisingly the plasma
resistance seems not to share the oscillatory behavior of electron density. Indeed discharge current is well fitted
by a double damped sine: π
ϕ
π
ϕ
=
+
+
+
τ
τ
−
−
i t
I
f t
I
f t
( )
sin(2
)e
sin(2
)e
,
(1)
t
t
2
1
1
1
(
/ )
2
2
2
(
/
)
1
2 (1) which corresponds to a double RLC circuit with constant component values (Fig. 2(c)). The low frequency oscil-
latory component decays with a characteristic time: which corresponds to a double RLC circuit with constant component values (Fig. 2(c)). The low frequency oscil-
latory component decays with a characteristic time: τ =
+
+
=
µ . L
L
R
R
s
2
490
(2)
p
2
1
2
2 (2) In this precise case, neglecting the contribution of the contact resistance between the electrodes and the spark,
we find the plasma resistance to be: In this precise case, neglecting the contribution of the contact resistance between the electrodes and the spark,
we find the plasma resistance to be: SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z 3 www.nature.com/scientificreports/ =
Ω. R
15
(3)
p =
Ω. R
15
p (3) We can evaluate the plasma conductivity σp following: σ
π
≈
∆
L
R
r
,
(4)
p
p
gap
2 σ
π
≈
∆
L
R
r
,
p
p
gap
2 (4) where Lgap is the discharge gap length and Δr is the radius of the plasma equivalent conductor, taken as the
electron density profile HWHM. Since the plasma radius was measured to be ~500 μm (Fig. 2(b)), σp is on the
order of 104 S · m−1. The pressure in the plasma is expected to be back to atmospheric pressure after a few hundred
microseconds38. In this case temperature can be derived from plasma conductivity by computing transport coef-
ficients of high temperature air39. This leads to a plasma temperature of ~13000 K. Since p ~ patm ≈ 105 Pa, we can
also estimate the air density in the plasma using the ideal gas law: where Lgap is the discharge gap length and Δr is the radius of the plasma equivalent conductor, taken as the
electron density profile HWHM. Since the plasma radius was measured to be ~500 μm (Fig. SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z Results 4(b), the current pulse generated by the gap closure has the characteristic shape
of an exponential-decaying pulse from a RC circuit with a very long duration of more than 30 ms and a low peak
amplitude of 100 mA. Note that the total electric energy is equivalent to the one used with the double circuit (70
J vs. 42 J). The long current decay thus ensures that the low current pulse will result in a discharge with a much
longer duration than with the Marx generator. g
g
With such a simple setup, we therefore achieved a discharge duration one order of magnitude higher than the
current record obtained for filamentation-triggered arcs26. The corresponding plasma resistance has a completely
different behavior from that of long-lived, high current discharges. First, the order of magnitude of this param-
eter peaks at 100 kΩ, which is 104 times higher than previously. Such a high resistance is very uncommon for
discharges, still it does not prevent the plasma from reaching an unprecedented lifetime. Second, the resistance SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z 4 entificreports/
Figure 3. Imaging long-lived, high current discharges with a high speed camera. (a) False color sample
images taken when the discharge current is either at a local extremum or at 0. (b) Time evolution of the spatial
maximum of the plasma luminosity recorded by the camera, averaged over the discharge length. Error bars
correspond to a confidence interval of ±1 standard deviation. (c) Time evolution of the normalized RMS
distortion of the discharge plasma. The distortion slowly increases with time, experiencing sudden surges when
the discharge current is near 0. www.nature.com/scientificreports/ Figure 3. Imaging long-lived, high current discharges with a high speed camera. (a) False color sample
images taken when the discharge current is either at a local extremum or at 0. (b) Time evolution of the spatial
maximum of the plasma luminosity recorded by the camera, averaged over the discharge length. Error bars
correspond to a confidence interval of ±1 standard deviation. (c) Time evolution of the normalized RMS
distortion of the discharge plasma. The distortion slowly increases with time, experiencing sudden surges when
the discharge current is near 0. also strongly varies with time, reaching a steady state by 1 ms at ≈50 kΩ before sharply increasing at the end of
the discharge, when plasma is starved of current, reaching 400 kΩ by 30 ms. Results C
d
h
d
h
h
2 l
(
A
A
l
)
d h Compared to the Marx discharges, the current is ~102 lower (100 mA versus ~10 A at long times) and the
plasma resistance is ~104 higher (100 kΩ versus ~10 Ω), meaning the Joule heating should stand at the same level
in both cases. Therefore, as the discharge stability directly depends on this parameter as shown by Shneider38,
plasma distortion in the case of low current discharges should remain at a level comparable to that of Marx
discharges. Consequently we used the same diagnostic as before: films recorded using a fast camera. Figure 4(c)
presents sample images of one such film, showing the discharge remains quite straight for a few milliseconds
before irremediably distorting near the grounded electrode. Evaluating the normalized RMS distortion as in SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z 5 www.nature.com/scientificreports/ Figure 4. Long duration, low current guided discharges. (a) Schematic description of the experimental setup. (b) Time evolution of the measured discharge current (blue), which follows an exponential decay (white), and
of the plasma resistance (red). (c) False color sample images of the discharge. (d) Time traces of the normalized
RMS distortion (blue) and of the estimated plasma temperature (red), showing that the Joule heating of the
plasma is not sufficient to prevent the distortion of the discharge at long times. Figure 4. Long duration, low current guided discharges. (a) Schematic description of the experimental setup. (b) Time evolution of the measured discharge current (blue), which follows an exponential decay (white), and
of the plasma resistance (red). (c) False color sample images of the discharge. (d) Time traces of the normalized
RMS distortion (blue) and of the estimated plasma temperature (red), showing that the Joule heating of the
plasma is not sufficient to prevent the distortion of the discharge at long times. the previous section yields the curve displayed in Fig. 4(d). One can see that the nRMSD equals 2% after 5 ms,
increasing linearly with time and increasing well above 10% at the end of the discharge. Looking at the previous
results (Fig. 3(c)), the 2% level was reached by only 800 μs with the oscillating high current. A continuous Joule
heating therefore appears more favorable than an alternating one to ensure the discharge stability. Results This can be
assessed by estimating the time evolution of the plasma temperature as it was done in the previous section: after
a few hundred microseconds the plasma is back to atmospheric pressure, meaning that the temperature can be
unambiguously extracted from a measurement of the plasma conductivity, which in turn can be readily extracted
from the plasma resistance and the plasma section. The result in plotted in Fig. 4(d): plasma temperature keeps
increasing for ~300 μs up to 4200 K before smoothly decaying, eventually reaching 3000 K after 30 ms as the cur-
rent is unable to sustain the Joule heating of the discharge. Inevitably this results in a loss of stability. Discussion Two main facts can be assessed from these experiments: first, the discharge plasma from a previous, short dura-
tion spark can be sustained for a much longer time by channeling electric energy from another source. Second,
this sustaining can be achieved using a very low current amplitude. The key parameter ensuring the discharge
stability appears to be the plasma temperature. When the temperature decreases, a flow from the surrounding air
will start to fill the low-density tube surrounding the plasma, eventually becoming turbulent and strongly disrupt-
ing the discharge straightness38. Conversely if the temperature can be maintained through the Joule heating of the
plasma, this deleterious effect can be prevented. p
,f
p
Therefore the lengthening of the discharge lifetime is an aspect that can be completely dissociated from the
lengthening of the discharge gap. Indeed already exist methods based on filamentation-guided discharges that
can be used to generate meter-long sparks using small-scale high-voltage sources41,42. Once a well-guided spark is
generated, only the external circuit supplying current to the plasma can play a role in the discharge stabilization. One has to be particularly careful to the current waveform used to make sure that the plasma temperature, and
therefore the discharge stability, is maintained. g
y
In these experiments we only used tabletop voltage sources and relatively small capacitors. With a larger power
supply, one could extend the lifetime of a guided discharge by several orders of magnitude, at least until convec-
tion of the generated hot air finally disrupts the channel. Methods Guided discharge generation. The generation of guided discharges was done using a chirped pulse ampli-
fication Ti:sapphire laser chain able to deliver pulses as short as 50 fs and with an energy up to 200 mJ. In the
case of the Marx generator, 200 mJ, 700 fs pulses were focused using a 5 m spherical lens, generating a ~2 m long
multifilament bundle both in the discharge gap and through the whole Marx generator. For the low-current dis-
charges, the spherical lens was replaced by an axicon lens with a 5° apex angle, yielding a much shorter plasma
column with a ~20 cm length using a 100 mJ, 50 fs laser pulse. As both setup used gaps initially charged with a
constant voltage, no synchronization was required between the laser system and the high-voltage circuits. 6 SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z www.nature.com/scientificreports/ Figure 5. Definition of the root mean square distortion at time t from side pictures of discharges: ridge of the
2D luminescence profile (black) and reference curve (light blue), that is the ridge of the luminescence profile
taken at t = 0. Figure 5. Definition of the root mean square distortion at time t from side pictures of discharges: ridge of the
2D luminescence profile (black) and reference curve (light blue), that is the ridge of the luminescence profile
taken at t = 0. Discharge diagnostics. =
∑
−
=
=
t
y
z
t
y
z
t
N
RMSD( )
(
( , )
( ,
0)) ,
(7)
i
N
i
i
1
max
max
2
pixels
pixels (7) Npixels being the number of pixels along z.h p
g
p
g
The normalized RMSD, or nRMSD, is just taken as: =
t
t
L
nRMSD( )
RMSD( ),
(8)
gap (8) where Lgap is the length of the discharge gap along z. A null nRMSD means that the discharge has exactly the same
shape as it has initially. A nRMSD equal to 1 means that the transverse distortions of the discharge with respect to
the reference path are on the order of the gap length, a very high value. where Lgap is the length of the discharge gap along z. A null nRMSD means that the discharge has exactly the same
shape as it has initially. A nRMSD equal to 1 means that the transverse distortions of the discharge with respect to
the reference path are on the order of the gap length, a very high value. Data availability. The datasets generated and analyzed during the current study are available from the cor-
responding author on reasonable request. Discharge diagnostics. •
Films of discharges were made using a Fastcam SA-X2 ultrafast camera from Photron, Inc.h g
g
•
The density of heavy species and of free electrons in the plasma was recorded using a two-color interferome-
ter. This works by recording simultaneously the plasma refractive index at two different wavelengths. As the
contribution of heavy species is almost independent of the wavelength, while it has a quadratic dependence
for free electrons, one can then solve an equation system with two unknowns to finally retrieve plasma densi-
ties37. Interferometry was performed transversely on the Marx generator discharges, followed by Abel inver-
sion of the recorded phase shift profiles, enabling us to extract free electron density and neutral density with
a 1 cm wide field of view, a 10 μm spatial resolution and a 10 time resolution, yielding a ~1022 m−3 resolution
for electron density and a ~1024 m−3 resolution for neutral density. y
y
•
For both low and high current discharges, current waveforms were recorded using current viewing resistors
(shunts) from T & M Research Products. y
y
For both low and high current discharges, current waveforms were recorded using current viewing resistors
(shunts) from T & M Research Products. (
)
•
Gap voltage for low-current discharges was tracked using a PVM-1 high-voltage probe from North Star High
Voltage. •
Gap voltage for low-current discharges was tracked using a PVM-1 high-voltage probe from North Star High
Voltage. Discharge shape stability indicator. We designed a scalar indicator to assess the shape stability of a guided
discharge, based on time-resolved side pictures of the arc. These pictures can be described as two-dimensional
(y, z) luminescence maps, where z is taken along the discharge axis (Fig. 5). For each picture, taken at different
times, the curve yielding the position ymax(z, t), that is the luminescence ridge position (black curve on Fig. 5), is
extracted. This curve is to be compared to a reference curve yref(z) (light blue curve on Fig. 5), which is taken as
the luminescence ridge curve ymax(z, t = 0) estimated at the breakdown time. The indicator, dubbed root mean
square distortion, or RMSD, is calculated at time t following: =
∑
−
=
=
t
y
z
t
y
z
t
N
RMSD( )
(
( , )
( ,
0)) ,
(7)
i
N
i
i
1
max
max
2
pixels
pixels
ber of pixels along z. References A simple high-voltage high current spark gap with subnanosecond jitter triggered by femtosecond laser
filamentation. Appl. Phys. Lett. 102, 163502 (2013). i
33. Klapas, D., Hackam, R. & Beanson, F. A. Electric arc power collection for high-speed trains. P. IEEE 64, 1699–1715 (1976). 34 Houard A et al High current permanent discharges in air induced by femtosecond laser filamentation Appl Phys Lett 90 1 i
33. Klapas, D., Hackam, R. & Beanson, F. A. Electric arc power coll 34. Houard, A. et al. High current permanent discharges in air induced by femtosecond laser filamentation. Appl. Phys. Lett. 90, 1
(2007).i 34. Houard, A. et al. High current permanent discharges in air induced by femtosecond laser filamentation. Appl. Phys. Lett. 90, 171501
(2007).i 35. Point, G., Arantchouk, L., Carbonnel, J., Mysyrowicz, A. & Houard, A. Plasma dynamics of a laser filamentation-guided spark. Plasmas 23, 093505 (2016).i 36. Arantchouk, L. et al. Compact 180-kv marx generator triggered in atmospheric air by femtosecond laser filaments. Appl. Phys. 104, 103506 (2014).i ,
(
)
37. Point, G. et al. Two-color interferometer for the study of laser filamentation triggered electric discharges in air. Rev. Sci. Instrum. 85,
123101 (2014).t 7. Point, G. et al. Two-color interferometer for the study of laser filamentation triggered electric discharges in air. Rev. Sci. Instrum. 85
123101 (2014).t neider, M. N. Turbulent decay of after-spark channels. Phys. Plasma yt
p
y
9. Capitelli, M., Colonna, G., Gorse, C. & D’Angola, A. Transport properties of high temperature air in local thermodynamic
equilibrium. Eur. Phys. J. D 11, 279–289 (2000).t t
39. Capitelli, M., Colonna, G., Gorse, C. & D’Angola, A. Transport properties of high temperature air in local thermodynamic
equilibrium. Eur. Phys. J. D 11, 279–289 (2000).t 0. Leonov, S. V., Isaenkov, Y. I. & Shneider, M. N. Suppression of the turbulent decay of an afterspark channel with residual current
Phys. Plasmas 14, 123504 (2007). y
,
(
)
41. Daigle, J.-F. et al. Dynamics of laser-guided alternating current high voltage discharges. Appl. Phys. Lett. 103, 184101 (2013).i y
1. Daigle, J.-F. et al. Dynamics of laser-guided alternating current high voltage discharges. Appl. Phys. Lett. 103, 184101 (2013). h
k
l
l
l
l
d d d
h
d b f
d l
fil
l
h 2. Arantchouk, L. et al. Large scale tesla coil guided discharges initiated by femtosecond laser filamentation in air. J. Appl. Phys. 116
013303 (2014). Conclusion In this Article we investigated two different schemes for increasing the lifetime of laser filamentation-guided
discharges based on the design of the discharge current waveform. In the first one, a first electrical circuit was
used to generate a first spark, before a second circuit started to discharge through the resulting plasma column,
sustaining it for more than 1 ms, three orders of magnitude longer than with the first circuit alone. In the sec-
ond scheme, a single, low amplitude and long duration current pulse was used directly from the inception of
the filament-triggered discharge, yielding an even longer arc of 40 ms. In both cases, the discharge stability was
maintained for ~1 ms by means of Joule heating from the current itself, preventing the turbulent decay of the
low-density tube surrounding the plasma column. Although these experiments were performed with relatively
small-scale discharges (85 mm), they can be easily transposed on larger setups because the initial spark generation SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z 7 www.nature.com/scientificreports/ and the subsequent sustaining of the discharge are completely uncorrelated. In recent experiments we increased
the gap length to the meter-scale without much difficulty. This will be reported later.i and the subsequent sustaining of the discharge are completely uncorrelated. In recent experiments we increased
the gap length to the meter-scale without much difficulty. This will be reported later.i g p
gfi
yh
p
As such, these results represent a significant achievement for the development of technologies in need of a
non-solid, long-lived and stable conductor like the virtual RF antenna or the contactless transfer of electrical
energy. g p
gfi
yh
p
As such, these results represent a significant achievement for the development of technologies in need of a
non-solid, long-lived and stable conductor like the virtual RF antenna or the contactless transfer of electrical
energy. References 1. Hercher, M. Laser-induced damage in transparent media. J. Opt. Soc. Am. 54, 563 (1964).f 2. Shen, Y. R. & Shaham, Y. J. Beam deterioration and stimulated raman effect. Phys. Rev. Lett. 15, 1008–1010 (1965). 3 S i kl
d D & M
G C
i
f
lifi d hi
d
i
l
l
O
C
56 219 221 (1985) ickland, D. & Mourou, G. Compression of amplified chirped optica f
3. Strickland, D. & Mourou, G. Compression of amplified chirped optical pulses. Opt. Commun. 56, 219–221 (1985 p
pi
p
p
p
p
4. Braun, A. et al. Self-channeling of high-peak-power femtosecond laser pulses in air. Opt. Lett. 20, 73–75 (1995).i g
g
p
5. Couairon, A. & Mysyrowicz, A. Femtosecond filamentation in transparent media. Phys. Rep. 441, 47–189 (2007).i i
6. Bergé, L., Skupin, S., Nuter, R., Kasparian, J. & Wolf, J.-P. Ultrashort filaments of light in weakly ionized, optically transparent media
Rep. Prog. Phys. 70, 1633 (2007).i p
g
y
7. Kasparian, J. & Wolf, J.-P. Physics and applications of atmospheric nonlinear optics and filamentation. Opt. Express 16, 466–493
(2008). (
)
8. Chin, S. L. et al. Advances in intense femtosecond laser filamentation in air. Laser Phys. 22, 1–53 (2012).hi i
9. Milchberg, H. M. et al. The extreme nonlinear optics of gases and femtosecond optical filamentation. Phys. Plasmas 21, 10
(2014).i 9. Milchberg, H. M. et al. The extreme nonlinear optics of gases and femtosecond optical filamentation. Phys. Plasmas 21, 100901
(2014). 10. Rosenthal, E. W. et al. Sensitivity of propagation and energy deposition in femtosecond filamentation to the nonlinear refractive 0. Rosenthal, E. W. et al. Sensitivity of propagation and energy deposition in femtosecond filamentation to the nonlinear refractiv
index. J. Phys. B 48, 094011 (2015). y
11. Vidal, F. et al. Modeling the triggering of streamers in air by ultrashort laser pulses. IEEE Trans. Plasma Sci. 28, 418–433 (2000 g
gg
g
y
12. Tzortzakis, S. et al. Femtosecond laser-guided electric discharge in air. Phys. Rev. E 64, 057401 (2001). 3. Cheng, Y.-H., Wahlstrand, J. K., Jhajj, N. & Milchberg, H. M. The effect of long timescale gas dynamics on femtosecond
filamentation. Opt. Express 21, 4740–4751 (2013). i
4. Wahlstrand, J. K., Jhajj, N., Rosenthal, E. W., Zahedpour, S. & Milchberg, H. M. Direct imaging of the acoustic waves generated by
femtosecond filaments in air. Opt. Lett. 39, 1290–1293 (2014).i i
p
15. References Lahav, O. et al. Long-lived waveguides and sound-wave generation by laser filamentation. Phys. Rev. A 90, 021801 (2014). l
d
f l
l
d
d d
h
l
f i
15. Lahav, O. et al. Long-lived waveguides and sound-wave genera 15. Lahav, O. et al. Long lived waveguides and sound wave generation by laser filamentation. Phys. Rev. A 90, 021801 (2014). 16. Point, G., Milián, C., Couairon, A., Mysyrowicz, A. & Houard, A. Generation of long-lived underdense channels using femtosecond
fil
h
(
) ,
g
g
g
yi
y
,
(
)
16. Point, G., Milián, C., Couairon, A., Mysyrowicz, A. & Houard, A. Generation of long-lived underdense channels using femtosecond
filamentation in air J Phys B 48 094009 (2015) 6. Point, G., Milián, C., Couairon, A., Mysyrowicz, A. & Houard, A. Generation of long-lived underdense channels using femtosecond
filamentation in air. J. Phys. B 48, 094009 (2015). i
7. Point, G., Thouin, E., Mysyrowicz, A. & Houard, A. Energy deposition from focused terawatt laser pulses in air undergoing
multifilamentation. Opt. Express 24, 6271–6282 (2016). i
p
p
8. Zhao, X. M., Diels, J. C., Wang, C. Y. & Elizondo, J. M. Femtosecond ultraviolet laser pulse induced lightning discharges in gases
IEEE J. Quantum Elect. 31, 599–612 (1995).i 19. La Fontaine, B. et al. Guiding large-scale spark discharges with ultrashort pulse laser filaments. J. Appl. Phys. 88, 610–615 (2000). 20 R
b
P S h
J & Di l
J C Hi h
l
l
i
l di h
i d
d b
l
h
l
l
J O
A 3 19. La Fontaine, B. et al. Guiding large-scale spark discharges with ultrashort pulse laser filaments. J. Appl. Phys. 88, 610–615 (2000). 20. Rambo, P., Schwarz, J. & Diels, J.-C. High-voltage electrical discharges induced by an ultrashort-pulse uv laser system. J. Opt. A 3, 19. La Fontaine, B. et al. Guiding large-scale spark discharges with g
g
gi
pp
y
0. Rambo, P., Schwarz, J. & Diels, J.-C. High-voltage electrical discharges induced by an ultrashort-pulse uv laser system. J. Opt. A 3
146 (2001).i 1. Rodriguez, M. et al. Triggering and guiding megavolt discharges by use of laser-induced ionized filaments. Opt. Lett. 27, 772–774
(2002). 22. Wang, T.-J. et al. Direct observation of laser guided corona discharges. Sci. Rep. 5, 18681 (2015). 23. Forestier, B. et al. References Triggering, guiding and deviation of long air spark discharges with femtosecond laser filament. AIP Adv. 2, 012151
(2012). 24. Clerici, M. et al. Laser-assisted guiding of electric discharges around objects. Sci. Adv. 1, e1400111 (2015). 25. Arantchouk, L. et al. Prolongation of the lifetime of guided discharges triggered
up to 130 μs. Appl. Phys. Lett. 108, 173501 (2016).hf 25. Arantchouk, L. et al. Prolongation of the lifetime of guided discharges triggered in atmospheric air by femtosecond laser filaments
up to 130 μs. Appl. Phys. Lett. 108, 173501 (2016).hf up to 130 μs. Appl. Phys. Lett. 108, 173501 (2016).hf 26. Théberge, F., Daigle, J.-F., Kieffer, J.-C., Vidal, F. & Châteauneu 26. Théberge, F., Daigle, J.-F., Kieffer, J.-C., Vidal, F. & Châteauneuf, M. Laser-guided energetic discharges over large air gaps by electric-
field enhanced plasma filaments. Sci. Rep. 7, 40063 (2017). hf
field enhanced plasma filaments. Sci. Rep. 7, 40063 (2017). i
pi
p
7. Dwyer, T. et al. On the feasibility of using an atmospheric discharge plasma as an rf antenna. IEEE Trans. Antennas Propag. 32
141–146 (1984).i 28. Brelet, Y. et al. Radiofrequency plasma antenna generated by femtosecond laser filaments in air. Appl. Phys. Lett. 101, 264106 (2012). 29 Kasparian J et al Electric events synchronized with laser filaments in thunderclouds Opt Express 16 5757–5763 (2008) adiofrequency plasma antenna generated by femtosecond laser filam Brelet, Y. et al. Radiofrequency plasma antenna generated by femtos 8. Brelet, Y. et al. Radiofrequency plasma antenna generated by femtosecond laser filaments in air. Appl. Phys. Lett. 101, 264106 (2012)
9. Kasparian, J. et al. Electric events synchronized with laser filaments in thunderclouds. Opt. Express 16, 5757–5763 (2008). 28. Brelet, Y. et al. Radiofrequency plasma antenna generated by femtosecond laser filaments in air. Appl. Phys. Lett. 101, 264106 (2
29. Kasparian, J. et al. Electric events synchronized with laser filaments in thunderclouds. Opt. Express 16, 5757–5763 (2008). i
29. Kasparian, J. et al. Electric events synchronized with laser filaments in thunderclouds. Opt. Express 16, 5757–5763 (20 i
30. Comtois, D. et al. Triggering and guiding of an upward positive leader from a ground rod with an ultrashort laser pulse-I:
experimental results. IEEE Trans. Plasma Sci. 31, 377–386 (2003). p
1. Comtois, D. et al. Triggering and guiding of an upward positive leader from a ground rod with an ultrashort laser pulse-II: modeling
IEEE Trans. Plasma Sci. 31, 387–395 (2003). 32. Arantchouk, L. et al. Author Contributions A.H. and A.M. conceived and supervised the project. G.P., L.A. and J.C. built the experimental devices. G.P., L.A.,
E.T., J.C. and A.H. performed the experiments. G.P., E.T. and L.A. conducted the data analysis. G.P. wrote the
manuscript. All authors contributed equally in discussing and interpreting results. Acknowledgementsh g
This research work was funded by the French Direction Générale de l’Armement (grant n° 2013.95.0901). We are
indebted to Jean-Lou Charles, Bernard Allali and Mickaël Martinez for their help with mechanics. 8 SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z www.nature.com/scientificreports/ SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z Additional Informationh Competing Interests: The authors declare that they have no competing interests. Publisher's note: Springer Nature remains neutral with regard to jurisdictional claims in published maps an
institutional affiliations. Open Access This article is licensed under a Creative Commons Attribution 4.0 International
License, which permits use, sharing, adaptation, distribution and reproduction in any medium or
format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Cre-
ative Commons license, and indicate if changes were made. The images or other third party material in this
article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the
material. If material is not included in the article’s Creative Commons license and your intended use is not per-
mitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the
copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. © The Author(s) 2017 SCiENtifiC RePorTs | 7: 13801 | DOI:10.1038/s41598-017-14054-z 9
|
https://openalex.org/W4200576479
|
https://www.duo.uio.no/bitstream/10852/92572/1/1-s2.0-S0378383921002131-main.pdf
|
English
| null |
A truncated, translated Weibull distribution for shallow water sea states
|
Coastal engineering
| 2,022
|
cc-by
| 6,748
|
1. Introduction and background in structural reliability assessment and design of coastal structures. Often, the joint distribution of several metocean variables are needed,
and the zero up-crossing wave period, mean wind speed and mean
wind-and wave directions are other relevant variables. For coastal
hazards, also the joint distribution of waves and water levels may be
relevant (Hawkes et al., 2002). The environmental contour method is
often used in structural reliability analysis based on the joint long-term
distributions of relevant metocean variables (Winterstein et al., 1993;
Haver and Winterstein, 2009). An alternative approach to combine
long-term distributions of sea states with short-term distributions of
structural response is recently proposed in Gramstad et al. (2020). Reliable probabilistic information about the long-term wave climate
is essential for the design and operation of marine and coastal structures
and other ocean engineering applications (Malliouri et al., 2021a;
Fazeres-Ferradosa et al., 2018a). Such information can be found in
wave data collected from in-situ measurements, satellite observations
or numerical wave models, but recorded time series are typically
supplemented by statistical models or probability distributions fitted to
the data. Hence, there is a need for appropriate distribution functions
to use for the long-term distribution of relevant metocean variables. Significant wave height is one of the most important wave parame-
ters in marine and coastal design, and it is a measure of the severity of
the sea state. One classical definition of significant wave height, 𝐻𝑆, is
that it is the mean of the highest one-third of the individual waves in
a sea state; alternative definitions are that it is four times the standard
deviation of the surface elevation or four times the square root of the
zeroth-order moment of the wave spectrum (Holthuijsen, 2007). Typ-
ically, the short-term distribution of individual wave heights in a sea
state is parametrized in terms of significant wave height and other sea
state parameters, and the sea state distributions are needed for a long-
term description of wave crests and heights (Mackay and Johanning,
2018; Bulgakov et al., 2018). Wave loads are typically described in
terms of significant wave height making this a very important variable Due to its importance in coastal and ocean engineering, a lot of
efforts have been made to find appropriate, parametric models for
the long-term distribution of significant wave height. A R T I C L E
I N F O Keywords:
Ocean waves
Marine structures
Shallow water
Significant wave height
Coastal environments
Statistical modelling
Probabilistic wave models Reliable probabilistic information of the long-term ocean wave climate is important in many coastal and
ocean engineering applications such as the design of marine and coastal structures. There is therefore a need
to establish accurate models for the long-term distribution of relevant metocean variables. One of the most
important wave parameters in marine design is the significant wave height, which is a measure of the severity
of the sea state, and wave loads are typically described in terms of this and other variables. Hence, a lot of
effort has been put on the proper probabilistic modelling of significant wave height. However, probability
distributions proposed to model significant wave height have mostly focused on deep water conditions and
less efforts have been put on shallow water conditions. This paper proposes a truncated, translated Weibull
distribution for the long-time distribution of significant wave height in shallow waters and demonstrates that
the model fit shallow water data quite well. In particular, the proposed model describes shallow-water wave
data better than the commonly used 3-parameter Weibull distribution, which is often the preferred distribution
for deep water locations. Coastal Engineering 172 (2022) 104077 Coastal Engineering 172 (2022) 104077 Available online 30 December 2021
0378-3839/© 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
∗Corresponding author at: DNV Group Research and Technology, Høvik, Norway.
E-mail addresses: Erik.Vanem@dnv.com (E. Vanem), tferradosa@fe.up.pt (T. Fazeres-Ferradosa).
https://doi.org/10.1016/j.coastaleng.2021.104077
Received 15 January 2021; Received in revised form 27 November 2021; Accepted 5 December 2021 ∗Corresponding author at: DNV Group Research and Technology, Høvik, Norway.
E-mail addresses: Erik.Vanem@dnv.com (E. Vanem), tferradosa@fe.up.pt (T. Fazeres-Ferradosa 1. Introduction and background (2019) presents a statistical dynamical model that
accounts for the strong positive skewness that are observed downstream
of an abrupt depth change. Subspace analysis is applied for the ex-
ceedance probability of shallow-water waves in a sea state in Šehić
et al. (2021). height (Ochi, 1998) and various beta and gamma-distributions were
fitted to significant wave height data in Ferreira and Guedes Soares
(1999) and Guedes Soares and Scotto (2001). The Rayleigh distribution
was compared to the Weibull distribution in Shariff and Hafezi (2012). Other parametric models used for significant wave height include
the exponential distribution, the Gaussian distribution, the skewness-
corrected log-normal distribution, the logistic distribution, and also
non-parametric approaches such as kernel-based models have been
proposed (Athanassoulis and Belibassakis, 2002). Recently, an exponen-
tiated Weibull distribution was proposed in Haselsteiner and Thoben
(2020). A maximum entropy distribution is proposed in Dong et al. (2013), and various more elaborated models include Bayesian mod-
els (Scotto and Guedes Soares, 2007), mixed models (Li et al., 2016),
fractal-based models (Liu et al., 2019), time-series models (Athanas-
soulis and Stefanakos, 1995; Scotto and Guedes Soares, 2000), spatial
models (Altunkaynak, 2005) and spatio-temporal models (Baxevani
et al., 2009; Vanem, 2013) to describe the long-term distribution of
significant wave height. Different extreme value models have also
been widely used to model extreme wave conditions (Jonathan and
Ewans, 2013). Several candidate models for significant wave height are
examined in Soukissian and Takvor (2021), and compared to a model
not previously applied to ocean data, i.e., the extended generalized
inverse Gaussian distribution. Results indicate that the proposed new
distribution outperforms the other candidate models for several, but
not all datasets that were analysed. Nevertheless, the 3-parameter
Weibull distribution is recommended in DNV’s recommended practice
on environmental loads (DNV, 2021) and remains a very common
approach for describing the distribution of significant wave height in
deep waters. The study presented in Malliouri et al. (2019) aims at obtaining a
more accurate description of the long-term wave climate in shallow
waters by combining short- and long-term statistics in deep waters. First, the joint long-term statistics of wave height and period in deep
waters are found by combining the conditional short-term joint dis-
tribution of these parameters with the long-term joint distribution of
sea states parameters significant wave height and mean zero-crossing
wave period. 1. Introduction and background Then, the joint distribution in shallow waters is estimated
by considering wave transformation of each individual wave as waves
propagate from the open sea towards shallower waters. They find that
wave statistics in shallower water differ from those in deeper waters,
but ends up with the same parametric family for intermediate waters as
in deep water for the long-term distribution of sea states, i.e. Weibull
or Gamma distributions for the significant wave height and conditional
lognormal for mean zero-crossing period. However, the distributional
parameters change. This statistical framework is applied to reliability
analysis of coastal structures in Malliouri et al. (2021b). A regional
frequency analysis of extreme sea states in coastal areas is reported
in Lucas et al. (2017). Notwithstanding the huge amount of literature focusing on the
probabilistic modelling of significant wave height, and the increasing
interest in the distribution of individual wave heights in shallow wa-
ter, there has been considerable less efforts on statistical modelling
of the long-term distribution of sea-state parameters such as signifi-
cant wave height especially for shallow water conditions. However,
it cannot be expected that probabilistic models used for sea states in
deep water conditions are equally suited for coastal waters (Bitner-
Gregersen, 2018). Hence, this paper proposes a truncated, translated
Weibull distribution for significant wave height in shallow waters. A
case study is shown where the proposed distribution function is fitted
to a set of data from a shallow water location and compared to the
standard 3-parameter Weibull distribution. Results indicate that the
truncated Weibull distribution yields better fit to the data than the
un-truncated one. The effect of marginal distribution of 𝐻𝑆on the
joint distribution of significant wave height and zero up-crossing wave
period is illustrated by environmental contours, again demonstrating
an improved fit to the data with the truncated model. It is well known that restricted water depths influence the dis-
tribution of wave heights, e.g. due to depth-induced wave breaking. Moreover, coastal waters may be fetch-limited, which would also pre-
vent generation of very large wind generated waves. The attenuation
of the average wave climate towards the coast were observed and
quantified from radar altimetry data in Passaro et al. (2021). Therefore,
different models are required to describe shallow water waves com-
pared to deep ocean waves (Battjes and Groenendijk, 2000; Méndez
and Castanedo, 2007; Wu et al., 2016). 1. Introduction and background The log-normal
distribution and the Weibull distribution, in its 2- or 3-parameter forms,
have been widely used to model significant wave height (Jasper, 1956;
Battjes, 1972; Mathisen and Bitner-Gregersen, 1990), and also hybrids
of these models have been suggested (Haver, 1985). However, there are
large model uncertainties in fitting a parametric model to significant
wave height data, a number of other probability distributions have
been explored (Ferreira and Guedes Soares, 2000). The generalized
gamma distribution have been proposed for modelling significant wave E. Vanem and T. Fazeres-Ferradosa Coastal Engineering 172 (2022) 104077 height (Ochi, 1998) and various beta and gamma-distributions were
fitted to significant wave height data in Ferreira and Guedes Soares
(1999) and Guedes Soares and Scotto (2001). The Rayleigh distribution
was compared to the Weibull distribution in Shariff and Hafezi (2012). Other parametric models used for significant wave height include
the exponential distribution, the Gaussian distribution, the skewness-
corrected log-normal distribution, the logistic distribution, and also
non-parametric approaches such as kernel-based models have been
proposed (Athanassoulis and Belibassakis, 2002). Recently, an exponen-
tiated Weibull distribution was proposed in Haselsteiner and Thoben
(2020). A maximum entropy distribution is proposed in Dong et al. (2013), and various more elaborated models include Bayesian mod-
els (Scotto and Guedes Soares, 2007), mixed models (Li et al., 2016),
fractal-based models (Liu et al., 2019), time-series models (Athanas-
soulis and Stefanakos, 1995; Scotto and Guedes Soares, 2000), spatial
models (Altunkaynak, 2005) and spatio-temporal models (Baxevani
et al., 2009; Vanem, 2013) to describe the long-term distribution of
significant wave height. Different extreme value models have also
been widely used to model extreme wave conditions (Jonathan and
Ewans, 2013). Several candidate models for significant wave height are
examined in Soukissian and Takvor (2021), and compared to a model
not previously applied to ocean data, i.e., the extended generalized
inverse Gaussian distribution. Results indicate that the proposed new
distribution outperforms the other candidate models for several, but
not all datasets that were analysed. Nevertheless, the 3-parameter
Weibull distribution is recommended in DNV’s recommended practice
on environmental loads (DNV, 2021) and remains a very common
approach for describing the distribution of significant wave height in
deep waters. bottom topography on the distribution of wave heights in shallow
waters is investigated in Bolles et al. (2019), Majda and Qi (2019),
and Majda et al. 1. Introduction and background Spectral wave models are often
used to simulate wave characteristics, and several wave models have
also been used for shallow waters, see e.g. Rusu et al. (2008) and
Fonseca et al. (2017), and a framework for downscaling wave reanaly-
ses to coastal areas combining dynamical and statistical downscaling
is presented in Camus et al. (2013). Another approach to describe
shallow water sea states is based on the empirical relationship between
deep sea characteristics and nearshore characteristics, and regression-
type statistical models can be established using for example neural
networks or other regression models, see e.g. Kalra et al. (2005) and
Browne et al. (2007). Regression models for coastal sea states with wind
data or other meteorological data as input has also been suggested in
e.g. Shamshirband et al. (2020) and Casas-Prat et al. (2014). The remainder of this paper is as follows. First, an introduction
to the truncated, translated Weibull distribution is given in Section 2. Then, a description of the data used in this study is presented in
Section 3 and the case study is presented in Section 4. Finally, a
summary and general conclusions is given in Section 5. There has recently been much interest in the statistics of shallow
water waves and several studies have been reported. However, there
seem to have been more focus on the statistics of individual wave
height compared to that of shallow water sea states. A recent study
based on deep waters measurements presented in Kvingedal et al. (2018) suggests that the Forristall distributions for individual wave
and crest heights generally fits the deep-water data well, but that
it is less accurate in steeper sea states corresponding to high wind
speeds. An analysis of laboratory data presented in Karmpadakis et al. (2019) and Zhang et al. (2019) confirms systematic departures from
the deep ocean distributions. It is suggested in Zhang et al. (2019) to
use a generalized Boccotti distribution (Alkhalidi and Tayfun, 2013) for
shallow water waves. The fact that the steepness and asymmetries of
extreme waves increase with shallower water depths is found by Chen
et al. (2018), which proposes an empirical parametrization of wave
steepness and asymmetries in nearshore environments. The effect of 4.1. Univariate distribution of significant wave height in shallow waters 4.1. Univariate distribution of significant wave height in shallow waters Waves in shallow water, on the other hand, are bounded by the
effect of the water depth and wave heights in shallow waters will have
an upper limit. These upper bounds will not be captured by the 2- or
3-parameter Weibull distributions. Hence, in this paper it is proposed
to rather use a 4-parameter Weibull distribution where the upper tail is
truncated by an additional parameter. As far as the authors know, this
distribution has not yet been applied to significant wave heights, but is
reported to be useful for describing wind speeds in Savenkov (2009)
and Kantar and Usta (2015). However, the distribution in Savenkov
(2009) is a left-truncated Weibull distribution, and the one proposed
in Kantar and Usta (2015) is a truncated 2-parameter distribution. Doubly-truncated versions of the Weibull distribution also exist (Zhang
and Xie, 2011). In this paper, however, a truncated and translated
Weibull distribution is proposed, corresponding to an upper-truncated
3-parameter Weibull distribution. First, the commonly used 3-parameter Weibull distribution is fitted
to the significant wave height data using standard maximum likelihood
(MLE) and maximized goodness of fit according to the 2nd order
Anderson–Darling statistic (A2D) and the Cramer–von Mises statistic
(CvM), respectively. The estimated pdfs and cdfs are shown in Fig. 2
together with the empirical ones. At first sight, the plots indicate a
reasonable fit to the data. However, focusing on the upper tail it
appears that there is an upper bound in the empirical distribution that
is not captured by the 3-parameter Weibull distribution, as shown in
the close-up plots in Fig. 3. The horizontal dashed lines in the plot of
the CDFs in Fig. 3 corresponds to return values for return periods of
10, 25, 50 and 100 years, respectively. Even though the various Weibull-fits look reasonable overall, it is
cleat that the upper tails are not well captured and that the model needs
to be improved. Hence, additional endpoint-parameter is introduced
and the truncated 3-parameter Weibull distribution is fitted to the data. It is noted that the endpoint is often assumed known, and may typically
be taken as the highest valued observation. However, in this study, this
is assumed to be an unknown parameter that is fitted by maximum
likelihood. However, in order to avoid unreasonable estimates for this
parameter, an upper bound is used in the optimization algorithms. 4.1. Univariate distribution of significant wave height in shallow waters In
this paper, an upper bound is assumed to be 0.6×𝑑where 𝑑denotes the
water depth. It is noted that this value is much higher than the highest
observed significant wave height in the data, and corresponds to an
upper bound on significant wave height of 10.8 m for this location. The upper-truncated, translated Weibull distribution is defined on
the interval 𝛾≤𝑥≤𝜏, where 𝜏is the truncation point, and has
cumulative distribution function 𝐺𝑋(𝑥) = 𝐹𝑋(𝑥)
𝐹𝑋(𝜏) = 1 −𝑒
−
( 𝑥−𝛾
𝛼
)𝛽
1 −𝑒
−
( 𝜏−𝛾
𝛼
)𝛽,
0 ≤𝑥≤𝜏. (3) (3) The probability density function is simply the derivative of this,
hence the truncated, translated Weibull distribution has pdf 𝑔𝑋(𝑥) = 𝑓𝑋(𝑥)
𝐹𝑋(𝜏) =
𝛽
𝛼
(
𝑥−𝛾
𝛼
)𝛽−1
𝑒
−
( 𝑥−𝛾
𝛼
)𝛽
1 −𝑒
−
( 𝜏−𝛾
𝛼
)𝛽
,
0 ≤𝑥≤𝜏. (4) The results of fitting the truncated 3-parameter Weibull distribution
to these data are shown in Figs. 4–5 and compared to the initial fits
using the un-truncated distribution. Only maximum likelihood fitting is
used for the truncated distribution, and it is obvious from Fig. 4 that the
truncated distribution is nearly identical to the un-truncated one based
on the same fitting technique. However, when zooming in on the tail
(Fig. 5), it is observed that the truncated distribution captures the upper
bound of the empirical distribution, which is an effect of the restricted
water depth. It is also noted that the estimated endpoint parameter is
just slightly higher than the maximum 𝐻𝑆observed in the data. The
estimated model parameters for the different models are presented in
Table 1. (4) Often, the truncation point 𝜏is assumed known, but in this paper this is
regarded as an additional model parameter that is estimated from the
data. Model parameters are estimated in this study by maximum likeli-
hood, as well as maximum goodness-of-fit. For a discussion on estima-
tion methods for the truncated Weibull distribution, reference is made
to Mittal and Dahiya (1989). It is observed that the parameters of the estimated truncated Weibull
distribution are nearly identical to the ones estimated for the un-
truncated version, using the same fitting technique (MLE). Hence, the
main body of the fitted distribution is hardly affected by the trunca-
tion. In order to aid model selection, the Akaike information criterion
(AIC) and the Bayesian information criterion (BIC) are used. These are
defined as follows 2. A truncated, translated Weibull distribution The 3-parameter, translated Weibull distribution is often used for
modelling significant wave height. It has probability density function 𝑓𝑋(𝑥) = 𝛽
𝛼
( 𝑥−𝛾
𝛼
)𝛽−1
𝑒
−
( 𝑥−𝛾
𝛼
)𝛽
,
𝑥≥𝛾
(1) (1) and cumulative distribution function 𝐹𝑋(𝑥) = 1 −𝑒
−
( 𝑥−𝛾
𝛼
)𝛽
,
𝑥≥𝛾,
(2) (2) where 𝛼is the scale parameter, 𝛽is the shape parameter and 𝛾is the
location parameter. Fitting such distributions to data amounts to esti-
mating these parameters, and several techniques exist including max-
imum likelihood, method of moments, least squares and minimization
of various goodness-of-fit measures. where 𝛼is the scale parameter, 𝛽is the shape parameter and 𝛾is the
location parameter. Fitting such distributions to data amounts to esti-
mating these parameters, and several techniques exist including max-
imum likelihood, method of moments, least squares and minimization
of various goodness-of-fit measures. 2 E. Vanem and T. Fazeres-Ferradosa E. Vanem and T. Fazeres-Ferradosa Coastal Engineering 172 (2022) 104077 4. Analysis and results The 3-parameter Weibull distribution has a lower bound of the
support dictated by the location parameter 𝛾, with 𝑓𝑋(𝑥) = 0 ∀𝑥< 𝛾,
and 𝛾= 0 reduces to the 2-parameter Weibull distribution with support
on [0, ∞). Hence, this distribution has no upper bound. 3. Data description In this study, data of significant wave height (𝐻𝑆) and zero up-
crossing wave period (𝑇𝑍) from a shallow water location are analysed. The data are extracted from hindcast data over an area in the Danish
sector of the North Sea with water depths ranging from 10 to 20 m. The exact location of the data being analysed in this paper is 55.725◦N
and 7.750◦E. The temporal resolution is 1 h and data from 124 months
from January 1. 2003 to May 1. 2013 are included, corresponding to
a total of 90 553 joint observations of 𝐻𝑆and 𝑇𝑍. The water depth at
this particular location is reported to be 18 m. The same data was used
in Fazeres-Ferradosa et al. (2018a) and Fazeres-Ferradosa et al. (2018b)
which give a more detailed description including a table of descriptive
statistics. 𝐴𝐼𝐶= 2𝑘−2 ln( ̂𝐿)
𝐵𝐼𝐶= 𝑘ln(𝑛) −2 ln( ̂𝐿),
(5) 𝐴𝐼𝐶= 2𝑘−2 ln( ̂𝐿) (5) 𝐵𝐼𝐶= 𝑘ln(𝑛) −2 ln( ̂𝐿), where 𝑘is the number of model parameters, 𝑛the sample size and ̂𝐿
is the maximized likelihood. The model with lowest value of AIC/BIC
is preferable according to these criteria. The AIC and BIC values for
the model alternatives fitted by MLE are included in Table 1. Since
AIC/BIC are based on the maximized likelihood, it would not be fair
to compare AIC and BIC for the models fitted by goodness-of-fit, so
these values are not reported. Indeed, both these models have a higher
threshold than the minimum value in the data, and would hence get
zero likelihood due to the poor fit of the lower part of the distribution. Notwithstanding, both AIC and BIC are lower for the truncated model,
confirming that this gives better fit to the data. A scatterplot of the data is shown in Fig. 1. Note in particular the
peculiar characteristics of the upper significant wave heights, which
presumably is an effect of the limited water depth. This feature makes
it difficult to obtain a good fit using the standard 2- or 3-parameter
Weibull distributions, but it will be demonstrated that reasonable fits
can be obtained using the truncated distribution. 3 Coastal Engineering 172 (202
d T. Fazeres-Ferradosa
Fig. 1. Scatterplot of the data of significant wave height and mean wave period. Fig. 2. Estimated density functions (left) and cumulative distribution functions (right) for the significant wave height data; 3-parameter Weibull. 3. Data description Table 1
Estimated model parameters for the 3-parameter Weibull distributions and the truncated distribution. Shape (𝛽)
Scale (𝛼)
Location (𝛾)
Endpoint (𝜏)
AIC
BIC
3p Weibull; MLE
1.52098
1.47108
0.13986
208 135
208 163
3p Weibull; A2D
1.10667
1.06753
0.43788
3p Weibull; CvM
1.25974
1.16200
0.33575
Truncated 3p Weibull; MLE
1.52194
1.47294
0.13985
6.11001
208 108
208 145 E. Vanem and T. Fazeres-Ferradosa Coastal Engineering 172 (2022) 104077 Fig. 1. Scatterplot of the data of significant wave height and mean wave period. Fig. 1. Scatterplot of the data of significant wave height and mean wave period. Fig. 1. Scatterplot of the data of significant wave height and mean wave period. Fig. 2. Estimated density functions (left) and cumulative distribution functions (right) for the significant wave height data; 3-parameter Weibull. Fig. 2. Estimated density functions (left) and cumulative distribution functions (right) for the significant wave height data; 3-parameter Weibull. Fig. 2. Estimated density functions (left) and cumulative distribution functions (right) for the significant wave height data; 3-paramet Table 1
Estimated model parameters for the 3-parameter Weibull distributions and the truncated distribution. Shape (𝛽)
Scale (𝛼)
Location (𝛾)
Endpoint (𝜏)
AIC
BIC
3p Weibull; MLE
1.52098
1.47108
0.13986
208 135
208 163
3p Weibull; A2D
1.10667
1.06753
0.43788
3p Weibull; CvM
1.25974
1.16200
0.33575
Truncated 3p Weibull; MLE
1.52194
1.47294
0.13985
6.11001
208 108
208 145
4.2. Joint distribution of significant wave height and wave period
effect of truncating the 3-parameter Weibull distribution on
di t ib ti
ill b
ill
t
t d b
l
l ti
i
t l 4.2. Joint distribution of significant wave height and wave period 4.2. Joint distribution of significant wave height and wave period effect of truncating the 3-parameter Weibull distribution on the joint
distribution will be illustrated by calculating environmental contours. effect of truncating the 3-parameter Weibull distribution on the joint
distribution will be illustrated by calculating environmental contours. A conditional model is assumed for modelling the joint distribution
of significant wave height and wave period, where the marginal distri-
bution of 𝐻𝑆is combined with a conditional log-normal distribution for
𝑇𝑍, conditioned on the value of 𝐻𝑆(Mathisen and Bitner-Gregersen, In many engineering applications, the joint distribution of several
metocean variables are needed and this study considers the joint distri-
bution of significant wave height and zero up-crossing wave period. The 4 E. Vanem and T. 3. Data description Fazeres-Ferradosa Coastal Engineering 172 (2022) 104077 Coastal Engineering 172 (202
and T. Fazeres-Ferradosa
Fig. 3. Close-up of upper tail of estimated density functions (left) and cumulative distribution functions (right) for the significant wave height data. Fig. 3. Close-up of upper tail of estimated density functions (left) and cumulative distribution functions (right) for the significant wave height data. Fig. 4. Estimated density functions (left) and cumulative distribution functions (right) for the significant wave height data; truncated 3-parameter Weibull. nsity functions (left) and cumulative distribution functions (right) for the significant wave height data; truncated 3-parameter Weibull. Fig. 4. Estimated density functions (left) and cumulative distribution functions (right) for the significant wave height data; truncated Fig. 5. Close-up of upper tail of estimated density functions (left) and cumulative distribution functions (right) for the significant wave height data. Fig. 5. Close-up of upper tail of estimated density functions (left) and cumulative distribution functions (right) for the significant wave height data. 5 E. Vanem and T. Fazeres-Ferradosa Coastal Engineering 172 (2022) 104077 Fig. 6. Environmental contours for joint distribution of 𝐻𝑆and 𝑇𝑍assuming a marginal 3-parameter Weibull (left) and a truncated Weibull (right). 7. Environmental contours for joint distribution of 𝐻𝑆and 𝑇𝑍assuming a marginal 3-parameter Weibull with different fitting methods; MLE (left), A2D (middle) and CvM
t). Fig. 6. Environmental contours for joint distribution of 𝐻𝑆and 𝑇𝑍assuming a marginal 3-parameter Weibull (left) and a truncated Weibull (right). contours for joint distribution of 𝐻𝑆and 𝑇𝑍assuming a marginal 3-parameter Weibull (left) and a truncated Weibull (right). Fig. 6. Environmental contours for joint distribution of 𝐻𝑆and 𝑇𝑍assuming a marginal 3-parameter Weibull (left) and a truncated W Fig. 7. Environmental contours for joint distribution of 𝐻𝑆and 𝑇𝑍assuming a marginal 3-parameter Weibull with different fitting methods; MLE (left), A2D (middle) and CvM
(right). Fig. 7. Environmental contours for joint distribution of 𝐻𝑆and 𝑇𝑍assuming a marginal 3-parameter Weibull with different fitting methods; MLE (left), A2D (middle) and CvM
(right). distribution of 𝐻𝑆and 𝑇𝑍assuming a marginal 3-parameter Weibull with different fitting methods; MLE (left), A2D (middle) and CvM Fig. 7. Environmental contours for joint distribution of 𝐻𝑆and 𝑇𝑍assuming a marginal 3-parameter Weibull with different fitting
(right) in shallow waters. 3. Data description The probabilistic model is almost identical to the
3-parameter Weibull distribution commonly used for modelling sig-
nificant wave height at deep sea locations, but provide a means for
truncating the upper part of the distribution to avoid predicting sea
states that would be unrealistic in shallow waters. 1990). The conditional model for 𝑇𝑍is fitted by binning data and
fitting a parametric model by least squares, see e.g. Vanem (2016)
for details. It is noted that the conditional model for 𝑇𝑍will obtain
the same parameters regardless of the marginal distribution for 𝐻𝑆,
but obviously different marginal distributions will give different joint
distributions. The proposed model is fitted to a shallow-water dataset with a
distinctive upper bound on observed significant wave height and it
is showed that it yields improved fit to the data compared to the
commonly used 3-parameter Weibull distribution. Moreover, statistical
model selection criteria confirm that the truncated model is an im-
provement. The effect of truncating the marginal distribution of 𝐻𝑆on
the joint distribution of 𝐻𝑆and 𝑇𝑍is also shown, by way of environ-
mental contour lines. This illustrates a big difference and suggests that
the standard distribution functions that are known to perform well for
deep-sea locations may not be used in shallow waters, where limited
water depth restricts large wave heights. Thus, it is suggested that
the truncated version of the 3-parameter Weibull distribution can be
a useful model for long-term metocean description in shallow waters
that can be utilized in design and analysis of coastal structures. Having estimated the joint distribution, environmental contours are
calculated using the direct sampling approach outlined in Huseby et al. (2013, 2015), using the tail sampling scheme suggested in Vanem
(2018). The resulting environmental contours are shown in Fig. 6
for initial 3-parameter Weibull distribution and the truncated Weibull
distribution, both fitted by MLE. Scatter plots of the data are included
in the plots. The 10-, 25-, 50- and 100-year contours are shown, and it
is clearly seen that the upper tail of the initial 𝐻𝑆distribution gives too
high and unrealistic sea states in this shallow water location. However,
this is remedied by the truncated Weibull distributions. As can be
clearly seen from Fig. 6, no overly unrealistic sea states are contained
within the modified contours. 3. Data description It is noted that the alternative fitting methods, based on goodness-
of-fit and with a particular focus on the upper tail of the distribution
yields even more unrealistic upper tails and even more unrealistic sea
states, as can be seen in Fig. 7 where contours for the alternative fitting
methods for the 3-parameter Weibull distribution are shown. References Assessing failure
probability of coastal structures based on probabilistic representation of sea
conditions at the structures’ location. Appl. Math. Model. 89 (1), 710–730. Browne, M., Castelle, B., Strauss, D., Tomlinson, R., Blumenstein, M., Lane, C., 2007. Near-shore swell estimation from a global wind-wave model: Spectral process,
linear, and artificial neural network models. Coast. Eng. 54, 445–460. Malliouri, D.I., Memos, C.D., Soukissian, T.H., Tsoukala, V.K., 2021b. Assessing failure
probability of coastal structures based on probabilistic representation of sea
conditions at the structures’ location. Appl. Math. Model. 89 (1), 710–730. Bulgakov, K., Kuzmin, V., Shilov, D., 2018. Evaluation of extreme wave probability on
the basis of long-term analysis. Ocean Sci. 14, 1321–1327. Malliouri, D.I., Memos, C.D., Tampalis, N.D., Soukissian, T.H., Tsoukala, V.K., 2019. Integrating short- and long-term statistics for short-crested waves in deep and
intermediate waters. Appl. Ocean Res. 82, 346–361. Camus, P., Mendez, F.J., Medina, R., Tomas, A., Izaguirre, C., 2013. High resolution
downscaled ocean waves (DOW) reanalysis in coastal areas Coast Eng 72 56 68 Camus, P., Mendez, F.J., Medina, R., Tomas, A., Izaguirre, C., 2013. High resolution
downscaled ocean waves (DOW) reanalysis in coastal areas. Coast. Eng. 72, 56–68. downscaled ocean waves (DOW) reanalysis in coastal areas. Coast. Eng. 72, 56–68. Casas-Prat, M., Wang, X.L., Sierra, J.P., 2014. A physical-based statistical method for
modelling ocean wave heights. Ocean Model. 73, 59–75. Mathisen, J., Bitner-Gregersen, E., 1990. Joint distributions for significant wave height
and wave zero-up-crossing period. Appl. Ocean Res. 12, 93–103. Casas-Prat, M., Wang, X.L., Sierra, J.P., 2014. A physical-based statistical method for
modelling ocean wave heights. Ocean Model. 73, 59–75. Chen, H., Tang, X., Gao, J., Fan, G., 2018. Parameterization of geometric characteristics
for extreme waves in shallow water. Ocean Eng. 156, 61–71. Méndez, F.J., Castanedo, S., 2007. A probability distribution for depth-limited extreme
wave heights in a sea state. Coast. Eng. 54, 878–882. DNV,
2021. Environmental
Conditions
and
Environmental
Loads,
DNV-RP-C205,
september 2019 ed. DNV. Mittal, M.M., Dahiya, R.C., 1989. Estimating the parameters of a truncated Weibull
distribution. Comm. Statist. Theory Methods 18 (6), 2027–2042. Dong, S., Tao, S., Lei, S., Cuedes Soares, C., 2013. Parameter estimation of the maximum
entropy distribution os significant wave height. J. Coast. Res. 28 (3), 597–604. Ochi, M.K., 1998. Ocean Waves the Stochastic Approach. In: Cambridge Ocean
Technology series, vol. 6, Cambridge University Press. Fazeres-Ferradosa, T., Taveira-Pinto, F., Romão, X., Vanem, E., Reis, M., das Neves, L.,
2018a. References Karmpadakis, I., Swan, C., Christou, M., 2019. Laboratory investigation of crest height
statistics in intermediate water depths. Proc. R. Soc. Lond. Ser. A Math. Phys. Eng. Sci. 475 (2229), 20190183:1–24. Alkhalidi, M.A., Tayfun, M.A., 2013. Generalized boccotti distribution for nonlinear
wave heights. Ocean Eng. 74, 101–106. Kvingedal, B., Bruserud, K., Nygaard, E., 2018. Individial wave height and wave crest
distributions based on field measurements from the northern north sea. Ocean Dyn. 68, 1727–1738. Altunkaynak, A., 2005. Significant wave height prediction by using a spatial model. Ocean Eng. 32, 924–936. Athanassoulis, G., Belibassakis, K., 2002. Probabilistic description of metocean parame-
ters by means of kernel density models 1, theoretical backgrounds and first results. Appl. Ocean Res. 24, 1–20. Li, W., Isberg, J., Waters, R., Engstöm, J., Svensson, O., Leijon, M., 2016. Statisti-
cal analysis of wave climate data using mixed distributions and extreme wave
prediction. Energies 9 (6), 396:1–17. Athanassoulis, G., Stefanakos, C.N., 1995. A nonstationary stochastic model for
long-term time series of significant wave height. J. Geophys. Res. 100 (C8),
16149–16162. Liu, G., Chen, B., Wang, L., Zhang, S., Zhang, K., Lei, X., 2019. Wave height statistical
characteristic analysis. J. Oceanol. Limnol. 37, 448–460. Lucas, C., Muraleedharan, G., Guedes Soares, C., 2017. Regional frequency analysis of
extreme waves in a coastal area. Coast. Eng. 126, 81–95. Battjes, J.A., 1972. Long-term wave height distribution at seven stations around the
british isles. Ocean Dyn. 25, 179–189. Mackay, E., Johanning, L., 2018. Long-term distributions of individual wave and crest
heights. Ocean Eng. 165, 164–183. Battjes, J.A., Groenendijk, H.W., 2000. Wave height distributions on shallow foreshores. Coast. Eng. 40 (3), 161–182. Majda, A.J., Moore, M., Qi, D., 2019. Statistical dynamical model to predict extreme
events and anomalous features in shallow water waves with abrupt depth change. Proc. Natl. Acad. Sci. USA 116 (10), 3982–3987. Baxevani, A., Caires, S., Rychlik, I., 2009. Spatio-temporal statistical modelling of
significant wave height. Environmetrics 20, 14–31. Bitner-Gregersen, E.M., 2018. Comparison of wind and wave climate in open sea and
coastal waters. Ocean Eng. 170, 199–208. Majda, A.J., Qi, D., 2019. Statistical phase transitions and extreme events in shallow
water waves with an abrupt depth change. J. Stat. Phys. 179, 1718–1741. Bolles, C.T., Speer, K., Moore, M., 2019. Anomalous wave statistics induced by abrupt
depth change. Phys. Rev. Fluids 4, 011801:1–8. Malliouri, D., Memos, C.D., Soukissian, T.H., Tsoukala, V., 2021a. 5. Summary and conclusions Erik Vanem: Idea, Conceptualization, Methodology, Analysis, Writ-
ing of paper. Tiago Fazeres-Ferradosa: Conceptualization, Methodol-
ogy, Validation, Review and editing. This paper has proposed a truncated, translated Weibull distribution
for modelling the long-term distribution of significant wave height 6 E. Vanem and T. Fazeres-Ferradosa Coastal Engineering 172 (2022) 104077 Declaration of competing interest Huseby, A.B., Vanem, E., Natvig, B., 2013. A new approach to environmental contours
for ocean engineering applications based on direct Monte Carlo simulations. Ocean
Eng. 60, 124–135. The authors declare that they have no known competing finan-
cial interests or personal relationships that could have appeared to
influence the work reported in this paper. Huseby, A.B., Vanem, E., Natvig, B., 2015. Alternative environmental contours for
structural reliability analysis. Struct. Saf. 54, 32–45. y
y
Jasper, N.H., 1956. Statistical distribution patterns of ocean waves and of wave induced Jasper, N.H., 1956. Statistical distribution patterns of ocean waves and of wave induced
stresses and motions with engineering applications. Trans. Soc. Nav. Archit. Mar. Eng. 64, 375–432. Acknowledgement Jonathan, P., Ewans, K., 2013. Statistical modelling of extreme ocean environments for
marine design: a review. Ocean Eng. 62, 91–109. This work has partly been carried out within the HIPERWIND
project, supported by EU H2020, grant agreement number 101006689. Kalra, R., Deo, M., Kumar, R., Agarwal, V.K., 2005. Artificial neural network to translate
offshore satellite wave data to coastal locations. Ocean Eng. 32, 1917–1932. Kantar, Y.M., Usta, I., 2015. Analysis of the upper-truncated Weibull distribution for
wind speed. Energy Convers. Manage. 96, 81–88. wind speed. Energy Convers. Manage. 96, 81–88. References Probabilistic design and reliability analysis of scour protections for offshore
windfarms. Eng. Fail. Anal. 91, 291–305. Passaro, M., Hemer, M.A., Quartly, G.D., Schwatke, C., Dettmering, D., Seitz, F., 2021. Global coastal attenuation of wind-waves observed with radar altimetry. Nature
Commun. 12, 3812:1–13. Fazeres-Ferradosa, T., Taveira-Pinto, F., Vanem, E., Reis, M.T., das Neves, L., 2018b. Asymmetric copula-based distribution models for met-ocean data in offshore wind
engineering applications. Wind Eng. 42, 304–334. Rusu, L., Pilar, P., Guedes Soares, C., 2008. Hindcast of wave conditions along the west
iberian coast. Coast. Eng. 55, 906–919. Savenkov, M., 2009. On the truncated Weibull distribution and its usefulness in
evalulating the theoretical capacity factor of potential wind (or wave) energy sites. University Journal of Engieering and Technology 1, 21–25. Ferreira, J., Guedes Soares, C., 1999. Modelling the long-term distribution of significant
wave height with the beta and Gamma models. Ocean Eng. 26, 713–725. Ferreira, J., Guedes Soares, C., 2000. Modelling distributions of significant wave height. Coast Eng 40 361 374 Ferreira, J., Guedes Soares, C., 1999. Modelling the long-term distribution of significant
wave height with the beta and Gamma models. Ocean Eng. 26, 713–725. Ferreira, J., Guedes Soares, C., 2000. Modelling distributions of significant wave height. Coast. Eng. 40, 361–374. Scotto, M., Guedes Soares, C., 2000. Modelling the long-term time series of significant
wave height with non-linear threshold models. Coast. Eng. 40, 313–327. Fonseca, R.B., Gonçalves, M., Guedes Soares, C., 2017. Comparing the performance of
spectral wave models for coastal areas. J. Coast. Res. 33 (2), 331–346. Scotto, M., Guedes Soares, C., 2007. BayesIan inference for long-term prediction of
significant wave height. Coast. Eng. 54, 393–400. Š Šehić, K., Bredmose, H., Sø rensen, J.D., Karamehmedović, 2021. Active-subspace
analysis of exceedance probability for shallow-water waves. J. Eng. Math. 126,
1:1–21. Gramstad, O., Agrell, C., Bitner-Gregersen, E., Guo, B., Ruth, E., Vanem, E., 2020. Sequential sampling method using Gaussian process regression for estimating
extreme structural response. Mar. Struct. 72, 102780:1–14. Guedes Soares, C., Scotto, M., 2001. Modelling uncertainty in long-term predictions of
significant wave height. Ocean Eng. 28, 329–342. Shamshirband, S., Mosavi, A., Rabczuk, T., Nabipour, N., K.-w. Chau, 2020. Prediction
of significant wave height; comparison between nested grid numerical model, and
machine learning models of artificial neural networks, extreme learning and support
vector machines. Eng. Appl. Comput. Fluid Mech. 14 (1), 805–817. Haselsteiner, A.F., Thoben, K.-D., 2020. Zhang, J., Benoit, M., Kimmoun, O., Chabchoub, A., Hsu, H.-C., 2019. Statistics of
extreme waves in coastal waters: Large scale experiments and advanced numerical
simulations. Fluids 4 (2), 99:1–24.
Zhang, T., Xie, M., 2011. On the upper truncated Weibull distribution and its reliability
implications. Reliab. Eng. Syst. Saf. 96 (1), 194–200. Vanem, E., 2018. 3-dimensional environmental contours based on a direct sampling
method for structural reliability analysis of ships and offshore structures. Ships
Offshore Struct. 14, 74–85. Wu, Y., Randell, D., Christou, M., Ewans, K., Jonathan, P., 2016. On the distribution
of wave height in shallow water. Ocean Eng. 111, 39–49. Winterstein, S., Ude, T., Cornell, C., Bjerager, P., Haver, S., 1993. Environmental
parameters for extreme response: Inverse FORM with omission factors. In: Proc.
6th International Conference on Structural Safety and Reliability. E. Vanem and T. Fazeres-Ferradosa References Predicting wave heights for marine design by Haselsteiner, A.F., Thoben, K.-D., 2020. Predicting wave heights for marine design by
prioritizing extreme events in a global model. Renew. Energy 156, 1146–1157. Haver, S., 1985. Wave climate off northern Norway. Appl. Ocean Res. 7, 85–92. Shariff, A.A., Hafezi, M.H., 2012. Modelling significant wave height data of north sea:
Rayleigh vs Weibull distributions. Appl. Mech. Mater. 157–158, 652–657. Haver, S., Winterstein, S., 2009. Environmental contour lines: A method for estimating
long term extremes by a short term analysis. Trans. Soc. Nav. Archit. Mar. Eng. 116, 116–127. Soukissian, H., Takvor, ., 2021. Probabilistic modelling of significant wave height using
the extended generalized inverse Gaussian distribution. Ocean Eng. 230, 109061. Vanem, E., 2013. Bayesian Hierarchical Space-Time Models with Application to
Significant Wave Height. In: Ocean Engineering & Oceanography, vol. 2, Springer. Vanem, E., 2016. Joint statistical models for significant wave height and wave period
in a changing climate. Mar. Struct. 49, 180–205. Soukissian, H., Takvor, ., 2021. Probabilistic modelling of significant wave height using
the extended generalized inverse Gaussian distribution. Ocean Eng. 230, 109061. g
g
,
Vanem, E., 2013. Bayesian Hierarchical Space-Time Models with Application to
Significant Wave Height. In: Ocean Engineering & Oceanography, vol. 2, Springer. Vanem, E., 2016. Joint statistical models for significant wave height and wave period
in a changing climate. Mar. Struct. 49, 180–205. Hawkes, P.J., Gouldby, B.P., Tawn, J.A., Owen, M.W., 2002. The joint probability of
waves and water levels in coastal engineering design. J. Hydraul. Res. 40, 241–251. Vanem, E., 2013. Bayesian Hierarchical Space-Time Models with Application to
Significant Wave Height. In: Ocean Engineering & Oceanography, vol. 2, Springer. waves and water levels in coastal engineering design. J. Hydraul. Res. 40, 241–251. Holthuijsen, L.H., 2007. Waves in Oceanic and Coastal Waters. Cambridge University
Press. Vanem, E., 2016. Joint statistical models for significant wave height and wave period
in a changing climate. Mar. Struct. 49, 180–205. Holthuijsen, L.H., 2007. Waves in Oceanic and Coastal Waters. Cambridge University
Press. 7 Coastal Engineering 172 (2022) 104077
|
https://openalex.org/W1608534476
|
https://journals.vgtu.lt/index.php/JCEM/article/download/2693/2204
|
English
| null |
DECISION-MAKING MODEL FOR CHOOSING RESIDENTIAL BUILDING REPAIR VARIANTS
|
Journal of civil engineering and management
| 2,015
|
cc-by
| 7,751
|
Introduction proposed for that purpose, i.e. the technical, energy and
functional assessment. The second and third steps evalu-
ate the building use value, which determines the build-
ing quality and further repair activities performed based
on that. The fourth step requires to determine the repair
needs based on prior building condition assessment. Vari-
ous repair technologies can be employed, i.e. different
variants, requiring different expenditure. The last step
of the model is to show an optimum repair solution for
buildings, considering the limitations of the repair funds
available. Residential building management requires to maintain
the building in non-deteriorated condition and obliges
the administrator to reasonably invest funds for repairs
(art. 185 par. 1 of the Real estate management law). Difficulties involved in this process are the main rea-
son why vast experience and skills are required from
the administrator while making repair-related decisions. This involves multiple criteria evaluation of the build-
ing condition. Various factors are adopted to assess a
building condition. One of them is so called use value
(Niezabitowska et al. 2003; Orłowski, Szklennik 2011),
defined as the building ability to satisfy its users’ de-
mands. This ability is assessed by a set of measurable
features important for the use, i.e. technical, energy, vi-
sual and functional ones. Received 06 Sep 2013; accepted 02 Dec 2013 Abstract. During the use of buildings it becomes necessary to carry out repair works including modernisation. Decid-
ing on the choice of repair solutions is a difficult and complex task. Building administrators have to consider both, the
benefits of some repair works, and limitations due to the availability of funds. Selection of a repair solution, bearing in
mind the above, requires a comprehensive approach that will allow assessment of the building condition and determining
the repair scope required. The research conducted by the authors was aimed at developing a decision-making model and
its computer-aided implementation, taking into account a number of operating demands. The system algorithm proposed
comprises five stages including: building condition assessment, building use value evaluation, repair classification, mul-
tiple variants of repair and the choice of repair solutions. The article describes individual stages of the model in detail,
giving numerical application examples of the method for repair solution choice for five multi-family houses. Keywords: repair solution, operating requirements, building evaluation, repair, renovation. JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT
ISSN 1392-3730 / eISSN 1822-3605
2015 Volume 21(7): 893–901
doi:10.3846/13923730.2014.895411 Copyright © 2015 Vilnius Gediminas Technical University (VGTU) Press
www.tandfonline.com/tcem DECISION-MAKING MODEL FOR CHOOSING RESIDENTIAL BUILDING
REPAIR VARIANTS Robert Bucońa, Anna Sobotkab
aDepartment of Construction Project Engineering, Faculty of Civil Engineering and Architecture,
Lublin University of Technology, Poland
bDepartment of Geomechanics, Civil Engineering and Geotechnics, Faculty of Mining and Geoengineering,
AGH University of Science and Technology of Cracow, Poland Corresponding author: Robert Bucoń
E-mail: r.bucon@pollub.pl 1. Decision support methods and models for
building maintenance Building condition assessment, in addition to technical
deterioration, includes also other building features, such
as those related to its functionality, aesthetics, energy ef-
ficiency, etc. To this end, multiple criteria decision mak-
ing (MCDM) methods are used. The multiple criteria
(multiple factor) evaluation of a building has been the
subject of numerous analyses and research projects in
Poland and abroad, aimed at developing a comprehen-
sive method for determining the condition of a residential
building. The scholars’ interest in this subject has been so The building use value appraisal allows studying
its condition and establish the relevant repair needs. However, the problem encountered by residential build-
ing administrators lies in the funds available for repairs,
which are usually insufficient. This article presents the
methods for choosing the repair solution meeting the
above assumptions. It includes five steps in which vari-
ous calculation tools were used. The first stage includes
building condition assessment, also applying the methods 893 894 R. Bucoñ, A. Sobodka. Decision-making model for choosing residential building repair variants method to determine the significance of factors used to
evaluate a road bridge. far of scientific nature, however, presumably, the grow-
ing operational demands prescribed by law or from the
users will contribute to more intense actions aimed at
developing a suitable assessment method which would
be useful in practice. An interesting approach to the multiple criteria as-
sessment of building operating conditions is presented by
Kasprowicz (2005). He defines the operating condition
and identifies the assessment criteria based on a set of
requirements provided in the Construction Law. Selected
factors are divided to measurable (quantitative) and im-
measurable (qualitative) ones. He assumes that, depend-
ing on the type, properties and possibility to measure,
determine or calculate operating properties of a build-
ing, the operating features can be identified which can
be fixed, fuzzy or probabilistic values, which requires
application of proper measuring methods. p
An example of a comprehensive approach to build-
ing assessment is the LEED (Leadership in Energy and
Environmental Design) method created in 1990s, de-
scribed in detail by Roderick et al. (2009). This method
evaluates a building bearing in mind the sustainable de-
velopment principles, such as building location, use of
water resources, energy consumption, recycling of mate-
rials, internal environment, as well as material and tech-
nology innovation and regional environmental priorities. 1. Decision support methods and models for
building maintenance In the British BREEAM (Building Research Establish-
ment Environmental Assessment Method) system de-
scribed by Reed et al. (2011), while assessing a building,
the environmental protection requirements (saving water,
energy, eco-friendly and recyclable materials, pollution),
residents’ health requirements and building management
methods are considered. Even more varied requirements
are included in the German DGNB (German Sustaina-
ble Building Council) system, in which the evaluation
scope refers to the environmental, economic, social and
cultural, technical, design factors and building location
(Alchimoviene, Raslanas 2011). The equivalents of the
mentioned systems are the EU GreenBuilding, Australian
Green Star and Japanese CASBEE (Comprehensive As-
sessment System for Built Environment Efficiency) sys-
tems (Reed et al. 2011).i Kaklauskas et al. (2005) developed a method of
multiple criteria building assessment, aimed at deter-
mining the significance of repair and their completion
degree. The methods comprise six steps: (1) building
component evaluation criteria are selected, followed by
determining the importance of criteria; (2) the indices of
minimum and maximum objective are calculated for each
alternative solution; (3) and (4), respectively, the value
of each solution is determined and put in order; (5) the
degree of compliance with the requirements for every
solution is determined; (6) the repair priority is deter-
mined for all considered parts to be repaired. Using, for building evaluation, multiple factors with
different nature, with fixed, variable random and fuzzy
and more or less interrelated values has led to the devel-
opment of a model and systems supporting the decision
making – DSS. Such systems including multiple criteria
rankings of the MCDM phenomenon studied are based
on expert systems and artificial intelligence methods, us-
ing fuzzy sets, neural networks, evolutionary algorithms,
etc. A tool for diagnosing the condition of office build-
ings, allowing determination their modernisation cost
is TOBUS (European diagnostics and decision-making
Tool for Office Building Upgrading Solutions) (Cacca-
velli, Gugerli 2002). The system proposed encompasses
the evaluation of physical condition of building compo-
nents, functional ageing, energy consumption, the quality
of the internal environment. An example of a computer-aided repair decision sup-
port system is EPIQR (Energy Performance and Indoor
Quality Retrofit). It is used for estimation of building
renovation cost, taking into consideration the reasona-
ble use of energy and improving the standard of living
(Vilhena et al. 2011). 1. Decision support methods and models for
building maintenance It is an integrated system for diag-
nosing of building condition and computer-aided deci-
sion making as to the type and scope of repair projects,
including thermal improvement projects, with various
work scenarios, with continued control of the project
cost. Another example of a multiple criteria building ap-
praisal method is the POE (Post-Occupancy Evaluation),
developed by Preiser (1995). This method allows the as-
sessment of the technical, functional, behavioural, organisa-
tional and economic quality of building, while its extended
BPE (Building Performance Evaluation) version, created
by Preiser and Vischer (2005) is effective in assessing also
the building design and construction quality. Another example of a system supporting decisions
as to the allocation of funds for the repair of building
in Tainan is presented by Perng et al. (2007). To eval-
uate buildings the authors propose a solution based on
the multiple criteria TOPSIS analysis. To this end, they
identified ten factors which relate to the technical, politi-
cal and economic requirements. The result of the evalu-
ation is showing how much needed the repair is (with
a four-grade scale). The repair solutions were selected
with an evolutionary algorithm which defines the most
cost-effective repair methods for individual building,
considering the financial limitations. Many useful tools for building appraisal are pro-
posed by IDCOP (Innovation In Design, Construction &
Operation of Buildings for People), including the system
for assessing building façade, developed and presented
by Chen (2006). A facade innovation factor is applied
for this assessment, which depends on how a number of
requirements are complied with, including the adaptive
abilities, affordability, durability, energy consumption and
aesthetic, sound, heat comfort requirements and others. An application example of the FAHP method to de-
termine the significance of the operating requirements
is presented in the work of Pan (2008). He applied that 895 Journal of Civil Engineering and Management, 2015, 21(7): 893–901 Application of the evolutionary algorithms in com-
plex DSS models, aimed at developing the repair policy
for buildings, are presented in the work of Juan et al. (2009). To evaluate the building quality, the authors pro-
pose application of such criteria as the safety, usability,
user health, comfort of use, usefulness. The effect of each
of them is assessed with the AHP method. To show re-
pair solutions, they suggest application of an evolution-
ary algorithm based on two various (priorities) objective
functions. 1. Decision support methods and models for
building maintenance The aim of the first one is to determine the
most cost-effective scope of repair, for which no assumed
repair budged, is exceeded. The other is aimed at show-
ing the most favourable repair options in terms of cost,
assuming that the minimum threshold level of building
quality and the target level identified by the decision-
maker would be achieved. Fig. 1. Decision-making model flowchart In the literature other interesting decision making
systems in building maintenance are presented, in which
such tools as the Markov chains are applied to describe the
risk occurrence of building elements failure or the optimal-
isation methods to the allocation of repair financial means,
e.g. Lounis and Vanier (2000), Langevine et al. (2006). Fig. 1. Decision-making model flowchart works in an existing building which not only concerns
the restoration of building original state but also leads
to its improvement according to requirements of chang-
ing regulations and requirements of building users or
owners”. Another example of the DSS and selection of alter-
native repair options is the Decision Support Model for
Semi-Automated Selection of Renovation Alternatives
proposed by Rosenfeld and Shohet (1999). Its structure
comprises four modules: (1) building compliance with
the legal and environmental requirements is initially
analysed; (2) the physical and functional condition is
assessed; (3) feasible actions are proposed to improve
building condition, and alternative solutions are devel-
oped; (4) the qualitative and technical and economic
comparison of the (feasible) alternatives is performed. i 2.2. Operating (maintenance) requirement
assessment Three Kj criteria were assumed which are the basis for
building use value (WUB) assessment: K1 – technical
condition; K2 – functional status and K3 – energy status. Technical condition assessment. A set of building
components was determined by E = {E1, E2, ..., En},
based on which the building deterioration is evaluated. While assessing the technical condition of a building,
such components as walls, floors, roof, stairs, balconies,
vestibules etc. were considered. The Ei ∈ E components
are assessed based on a set of factors Ei = {u1, u2, ..., up}
describing its damage, e.g. while assessing the walls:
cracks, subsiding, vertical tilt and humidity. Identification and analysis of the methods and mod-
els applied in the above chosen DSS systems for building
maintenance, taking into consideration multiple criteria
of rankings, served as the grounds for the authors’ work
on the development of an original method for selection
of an appropriate variant from multiple options possible,
considering the multiple criteria building assessment and
limited funds for the repair works. To evaluate the technical condition OK1, the weight-
ed average method was adopted (Bucoń, Sobotka 2012),
in which the building wear index is expressed in a
0÷100% scale. Individual building components are as-
sessed visually, hence the assessment represents also the
visual condition: 2.3. Assessing use value of buildings expert determines the component deterioration
, using
the linguistic rank scale: good – G; satisfactory – S; me-
dium – M; poor – P; bad – B, to which the deterioration
grades, expressed in %, are assigned respectively 0÷15,
16÷30, 31÷50, 51÷70, 71÷100. The building use value WUB is calculated based on the
assessment of three criteria Kj. Each of them is repre-
sented by a linguistic variable xj expressed by fuzzy sets
in some space xj: Functional status assessment. A set of building fea-
tures C = {C1, C2, ..., C5}, was determined according to
which its functional status will be assessed. (4) To assess the building functional status, the fea-
tures considered were: functionality of balconies and
entrances, communication inside the staircase, safety
and security and ventilation. The rank assessment of
all building features assumed Ci ∈ C is affected by nu-
merous factors Ci = {c1, c2, ..., co}, e.g. while assessing
a balcony: the area, finishing, safety, furnishing, visual
aspects etc. where:
– degree of belonging to
fuzzy set;
i – the number of fuzzy sets for each of the jth criteria:
where:
denote fuzzy
sets to be evaluated according to the K1 criterion;
where:
denote fuzzy
sets to be evaluated according to the K2 criterion;
where:
denote fuzzy
sets to be evaluated according to the K3 criterion. where:
– degree of belonging to
fuzzy set;
i – the number of fuzzy sets for each of the jth criteria: To evaluate the functional status OK2, as above,
the weighted average method was adopted which, in this
case, consists in evaluating building features Ci based
on the compliance with the requirements for each of the
ci factors: 3
Each of the
fuzzy sets, except for the extreme
ones, is expressed with a number of triangular member-
ship functions, the peaks of which are located in the cen-
tre of each of the n-adopted ranges. i Fuzzification of the input variables required de-
termining the number of fuzzy sets and establishing
the characteristics and shape of membership functions
describing them. The model assumes fuzzification of
each input variable in such a manner that the division
correspond to the categorisation method applied in
practice.
(2) (2) where: wCi– significance of the feature assessed;
–
functional status feature rank [points]. Functional assessment of building feature is given in
a 0÷5 points scale. 2.3. Assessing use value of buildings Based on the building feature condi-
tion Ci, an expert grades it
with the linguistic rank
scale: good – G; satisfactory – S; medium – M; poor –
P; bad – B; no component – N, to which the grades 5÷0
points are assigned. Five grading categories were adopted for the input
variable describing the technical condition, according to
the division adopted in building periodic inspection re-
ports. The categories were described with five fuzzy sets
using linguistic descriptions: good – G; satisfactory – S;
medium – M; poor – P; bad – B, for which the degree
of deterioration expressed in %, is, respectively: 0÷15,
16÷30, 31÷50, 51÷70, 71÷100. Energy status assessment. A set of building com-
ponents E = {E1, E2, ..., En} was determined to assess
its energy status. Some components Ei ∈ E, such as
the walls, roof, basement floor, door and window join-
ery etc. correspond to those assessed against the K1
criterion. The other variable representing the functional sta-
tus was divided to two ranges, which are described
with three fuzzy sets with triangular belonging, repre-
senting the values: bad – B; medium – M; good – G, to
which the following values [points] apply: 0÷2,5; 0÷5;
2,5÷5. Assessment OK3 should be carried out according
to the methodology present in the standards of building
thermal protection. It leads to the calculation of energy
status assessment OK3 expressed in kWh/m2·year, deter-
mining on based seasonal building energy demand for
heating purposes: For a third input variable (energy status), the cat-
egorisation resulting from the proposed division to en-
ergy class (Pater, Magiera 2011) was adopted. Following
the naming adopted, the variable was divided into six
energy classes: low energy LE, energy-efficient EE, me-
dium energy-efficient MEE, medium energy-consuming
MEC, energy-consuming EC, high energy-consuming
HEC buildings, for which energy status expressed in
kWh/m2·year is respectively: 20÷45, 45÷80, 81÷100,
101÷150, 151÷250, >251.
(3) (3) where: Qh – seasonal demand for heating, [kWh/m2. –
year]; A – area of external partitions [m2]. Due to the fact that individual components consid-
ered while assessing the criteria adopted affect, to vari-
ous degree, the building operation, i.e. its technical and
functional status, their effects are varied by significance
levels. The significance of components assessed are de-
termined with the pseudo-fuzzy scaling method (Bucon,
Sobotka 2012). 2.1. General concept In the method proposed, the repair-related decisions de-
pend on three building qualities, i.e. the technical con-
ditions, energy and functional status, whereby each of
them is affected by a number of factors. Therefore this
is a complex calculation and decision-making problem. Based on the above ranks, a synthetic building use value
is determined, which determines the choice of the repair
solution that allows the highest increment of the building
use value in relation to the funds invested.
(1) (1) where: wEi– significance of the condition component
evaluated;
– technical deterioration of an ith compo-
nent of the building [%]; n – number of components as-
sessed for the K1 criterion. The methods for creating a decision-making model
included five main stages presented in the Figure 1. It should be noted that the term “repair” used
in the article indicates “performance of construction Individual building components Ei are assessed
according to the damage found ui, based on which an 896 R. Bucoñ, A. Sobodka. Decision-making model for choosing residential building repair variants 2.3. Assessing use value of buildings Relationships between the criteria grades are in-
cluded in a set of rules Rk providing details of the re-
lationships between the premises constituting the input
variables xj and conclusion representing the output
variable y. The output variable (rule conclusion) in 897 Journal of Civil Engineering and Management, 2015, 21(7): 893–901 Takagi-Sugeno-Kang (Takagi, Sugeno 1985) model
adopted is expressed in a form of a functional depend-
ency y = f(x1, x2, x3) between the inputs and output, and
in the premise part, this rule is of fuzzy nature. For the
model structure adopted, the set of rules can be presented
as follows: rule: “if the grades of the j criterion belong to
term,
then the input variable belongs to the WUB(n) singleton”,
N – number of all experts. Step 4. Calculating the conclusion value for each
generated rule Rk (the number of k rules equals the prod-
uct of fuzzy sets of input variables xj and equals 90). Step 4. Calculating the conclusion value for each
generated rule Rk (the number of k rules equals the prod-
uct of fuzzy sets of input variables xj and equals 90). To this end, for every ith fuzzy set of the jth criterion, the
membership function value and the number of fuzzy set
is selected, for which the membership function takes
the maximum value, according to the formula: j
To this end, for every ith fuzzy set of the jth criterion, the
membership function value and the number of fuzzy set
is selected, for which the membership function takes
the maximum value, according to the formula:
(5) where:
– degree of belonging of the input vari-
able x1, x2, x3 to fuzzy sets t, u, v; μWUB(n) (y) – degree
of belonging of the output variable y to WUB(n). . (7) Linguistic variables appearing on the left side of
fuzzy rules are the input variables and referred to as the
premises (t, u, v) being the activated fuzzy sets. The rule
is activated if the premises are met. The conclusion of
every rule is provided on the right of the equation. In the
model discussed, the output variable is expressed with
singletons describing the building use value. 2.3. Assessing use value of buildings j
Gathering information for every expert participating
in the research involves filling in a form, in which the
experts assign all the input variable values x1 (G, S, M,
P, B), x2 (G, M, B), x3 (LE, EE, MEE, MEC, EC, HEC)
to one of five values of the output variable y describing
WUB (VH, H, M, A, L), e.g. if x1 = G and x2 = G and
x3 = LE÷EE then y = VH. Concluding. At this stage, every rule, the premises
of which are met, is activated. Generally, based on the
premises (t, u, v), an appropriate output value WUB(n)
is found, which is the conclusion from the fuzzy rules
adopted. Concluding with a rule base is performed in two
steps: Step 2. Calculating criteria significance. The fuzzy
extension of the AHP method was adopted, described
in detail in the work of Jaskowski et al. (2010). This
method allows determination of criteria significance by
aggregation of ranks of the K group of experts – each of
them performs m = n . (n–1)/2 comparisons with pairs of
criteria on a given problem priority level (the relative ex-
ceeding, preference, significance levels are determined)
with the scale 1/9, 1/7, 1/5, 1/3, 1, 3, 5, 7, 9 extended
possibly by the intermediate ranks 1/8, 1/6, 1/4, 1/2, 2, 4,
6, 8. Aggregation of expert opinions is aimed at finding
one common significance rank on the criteria adopted. Step 1. Calculating the level of belonging μ
of
the premises i = t, u, v being the fuzzy sets of the three
input variables xj . j
Step 2. Calculating the degree of meeting the entire
condition (rule) as a membership function of the product
of fuzzy sets being calculated with the prod operator:
(9) (9) Sharpening. Calculation of the building use value is the
result of activating the conclusion of individual system
rules. The sharpening process requires an appropriate
defuzzification method. For the Takagi-Sugeno-Kanga
model, the “weighted sum” method was adopted
(Takagi, Sugeno 1985). The value is determined as a
weighted average of the values obtained from the rules
activated: Sharpening. Calculation of the building use value is the
result of activating the conclusion of individual system
rules. The sharpening process requires an appropriate
defuzzification method. For the Takagi-Sugeno-Kanga
model, the “weighted sum” method was adopted
(Takagi, Sugeno 1985). 2.3. Assessing use value of buildings Further on, for every rule Rk generated, the following Kk
conclusion is calculated:
(8) (8) where:
– premises of the jth criterion respectively for
i = u, t, v, whereas u = 1, 2,.., 5, t = 1, 2, 6, v = 1, 2, 3;
wj – significance of the input variable j = 1, 2, 3; WUB( ) –
WUB determined for the ith set
of variable xj. Rule base. In this paper an original algorithm for
generating the base of system rules is presented (Bucoń,
Sobotka 2012), which forms an integral part of the model
developed. It is based on expert knowledge in assess-
ing building use value, which requires the following
activities: j
Step 5. To every kth rule R, a value of the output
variable WUB(n) is assigned, based on the conclusion
factor K1 calculated for it. It is related, to a varied extent,
to the degree of belonging to two different WUB values,
which leads to a conflict and doubling the number of
rules. As a solution to avoid such situation, the value
WUB(n) is assumed, for which the level of belonging
is higher. Step 1. Expert research. It consists in assigning each
of five values of the output variable of WUB expressed
in points: very high VH (100), high H (70), medium M
(50), average A (30), low L (10) of the input variables xj. Gathering information for every expert participating
in the research involves filling in a form, in which the
experts assign all the input variable values x1 (G, S, M,
P, B), x2 (G, M, B), x3 (LE, EE, MEE, MEC, EC, HEC)
to one of five values of the output variable y describing
WUB (VH, H, M, A, L), e.g. if x1 = G and x2 = G and
x3 = LE÷EE then y = VH. i Step 1. Expert research. It consists in assigning each
of five values of the output variable of WUB expressed
in points: very high VH (100), high H (70), medium M
(50), average A (30), low L (10) of the input variables xj. 2.4. Repair classification of buildings and designing
variant-based repairs
(12) (12) Building repair recommendations are based on the
calculated WUB. If several buildings are assessed
B = {B1, B2, ..., Bk} it is possible to choose those of
them for which the profitability of repairs aimed at in-
creasing their use value will be analysed. This can be
performed in two ways, i.e. by assuming such buildings
for which the WUB calculated does not exceed a specific
determined threshold value, or those for which the dif-
ference in the WUB assessment is greater than a specific
value. The most satisfactory solution, selected from a set of ac-
ceptable solutions, should correspond to the maximum
value of adaptation function, ensuring the highest in-
crease of building(s) use value. This solution is a com-
bination of different repair variants, the cost of which
should not exceed the funds available for the repair. The
problem can be simplified as follows: The most satisfactory solution, selected from a set of ac-
ceptable solutions, should correspond to the maximum
value of adaptation function, ensuring the highest in-
crease of building(s) use value. This solution is a com-
bination of different repair variants, the cost of which
should not exceed the funds available for the repair. The
problem can be simplified as follows: ,
(13) (13) The repairs (scope, technology) for the designat-
ed buildings are determined based on the evaluation of
technical condition of components, energy and func-
tional status. The objective is to propose an appropri-
ate repair technology (preferably in several variants),
for which it is required to estimate the cost of them
and calculating the value increase of the criteria Kj,
adopted in the paper, using the assessment method pro-
posed in Section 2.2. All repair works proposed at this
stage should ensure operation of the existing building
at the standard complying with the provisions of the
Construction Law and other legislation and standards. For each building Bi ∈ B designated to repair, based
on the Kj criteria assessment, a set of possible repair
activities NBi is determined. Every repair Nis ∈ NBi can
be performed in a number of possible ways, so called
variant, each from which represents a different solution
in terms of the materials used, technology and cost of
implementation. 2.3. Assessing use value of buildings The value is determined as a
weighted average of the values obtained from the rules
activated: Step 3. Calculation is made of the degree of belong-
ing
of the input variables xj fuzzy sets to the
output variable value WUB(n), expressed in the VH, H,
M, A, L singletons, based on the information received
from experts (step 1):
(6) (6)
(10) (10) where:
– the number of experts to confirm the 898 R. Bucoñ, A. Sobodka. Decision-making model for choosing residential building repair variants buildings ∆WUB(Bi). Considering, in the Eqn (12), of
use area of each of the buildings Pu(Bi), it is possible
to determine the best repair solution resulting in the
maximum use value increase for all buildings analysed
altogether: where: y – sharpened building use value; WUB(n) –
output variable values expressed as singletons;
–
degree of belonging (activation) of the output variable
WUB(n) for each activated rule Rk. 2.4. Repair classification of buildings and designing
variant-based repairs where: w – solution including a set of acceptable repair
solution variants of all buildings; ∆WUB(w) – building
use value increase for the w solution; K(w) – cost of the
w solution. To solve the optimising task, an evolutionary
algorithm was applied, aimed at seeking optimal or sub-
optimal (acceptable) solutions. Individual stages of the
algorithm comprise the following steps: 1. Creating the initial population – initial solutions; 1. Creating the initial population – initial solutions; 2. Generating repair solutions; 3. Evaluation of the repair solutions. Representation of individuals (acceptable solutions) was
adopted in a form of genes containing information of the
building for which the repair variant is proposed. The
value of individual genes in a chromosome is established
randomly. Chromosome coding is contained in the geno-
type described in Table 1. Symbols: Bi – number of buildings forming a chro-
mosome, i = 1, 2, 3,…, k; repairs Nis from the set of
repairs for every building
for
s = 1, 2, 3,…, m;
– repair variant for ith building,
r = 1, 2,..., v. 2.5. Optimising the selection of repair solutions The problem of selecting the repair solution, in the model
developed, involves: Generating possible repair solutions being assessed
by the adaptation functions takes place in the tournament
selection, one-point crossover and uniform mutation
processes. –– maximising the increase of building use value while
limiting; –– maximising the increase of building use value while
limiting; –– funds available to carry out the repair. As a result of optimisation, out of the buildings repairs
proposed NBi the w solution is determined which is a
set of repair variants
, ensuring the highest use value
increase for the amount assumed K (which is the limit-
ing factor). An increase of building use value ∆WUB(Bi)
is the result of the value increase of three input criteria
: Optimal solutions are sought with two adaptation
functions F1 and F2, which aim to find the best repair
solution in terms of use value increase for the solutions
which a) do not exceed the F1 budged assumed and
b) exceed the budget F2: Table 1. Representation (coding) of repair solutions
Bi
1
2
3
k
Nis
3
5
.. 12
2
7
.. 15
1
5
.. 8
.. 1
2
.. 3
3
1
.. 1
2
2
.. 1
..
(11) (11) where: wKj – significance of the jth criterion. j i
The increase of the use value of all buildings
∆WUB is a sum of use value increase of individual Journal of Civil Engineering and Management, 2015, 21(7): 893–901 899 a)
(14)
b)
(15) obtained from archival documentation, e.g. annual and
5-year evaluation, energy audits, technical documenta-
tion. Then, the cost of suggested repair was estimated
and the value increase for the assessed building statuses
against the formula (1, 2, 3) was determined. Depending
on the repair chosen, the increase may refer to one, two
or even three building statuses – see Table 5. a) (15) b) where: K – cost of generated solution; B – assumed cost
(budget) for which the repair solution is sought; ∆WUB –
building use value increase; k – penalty factor. The results are a starting point towards optimalisa-
tion, i.e. the choice of repair scope bringing the largest
WUB increase assuming having limited repair funds. The adaptation function F2 allows searching a
broader range of possible acceptable solutions. The cost
K of the solution can slightly exceed the budget assumed
B. 2.5. Optimising the selection of repair solutions These results in solutions of higher effectiveness (re-
pair cost-effectiveness in relation to the cost) presented
with the formula: The application of developed model was presented
in the example of cases. The optimalisation task in the
first case is to choose the repair scope for all the build-
ings altogether, while in the second one for each building
separately.i
(16) (16) In the first case all the repairs proposed by the ad-
ministrator were sought, for which the cost will be within
or slightly exceed the budget of PLN 4,500,000 and the
largest WUB increase will be obtained. As a result of The possibility to adjust the k factor in the Eqns (14)
and (15) allows certain flexibility in finding solutions
which are acceptable to the decision-maker, considering
the possibility to exceed or not fully use the budget as-
sumed. The penalty for exceeding depends on the k factor
assumed, which makes it possible to control the possibil-
ity of potential exceeding of the budget assumed. Table 3. Proposed repair and variants for 5 buildings Table 3. Proposed repair and variants for 5 buildings Table 3. Proposed repair and variants for 5 buildings
Building
Repair activities
Repair variants
1
13
20
2
16
24
3
16
23
4
13
21
5
12
20 3. Model application example On the basis of the proposed computational algorithm
shown in Figure 1 and described in Section 2, a computer
repair decision support system (SWDR) was developed. It enables optimalisation calculations. Building assess-
ment against the Kj adopted criteria are entered to the
system as input data, and WUB is the output. Table. 4. Façade wall repair variants of one building
Repair variants
Repair variants description
1/1
Façade walls thermal insulation
1/2
Façade walls thermal insulation
First floor wall cladding
1/3
Façade wall painting Table. 4. Façade wall repair variants of one building At first, buildings were evaluated against the Kj cri-
teria adopted, based on which the WUB use value was
determined. The calculation results are listed in Table 2. As a result of the calculations, it was assumed that
the buildings whose WUB assessment exceeds 50 points
will not be accepted for repair. Thus, all the analysed
buildings (Table 2) require activities increasing their use
value. With the agreement of a repair manager repair ac-
tivities were proposed for these buildings of which some
can be performed according to various methods – Table 3
(presentation of repairs) and Table 4 (example). Table 5. Sample of repair variants possible for building B1
(shown 5 out of 13 repairs) Repair
component
Repair
variant
[%]
[pt]
[kWh/
m2]
K
[PLN]
1
Façade
1
3.60
0.00
27.12
434,625
2
3.82
0.00
27.12
449,640
3
1.34
0,00
0.00
67,053
2
Roof
1
0.06
0.00
0.00
27,773
2
2.20
0.00
0.00
101,660
3
Building
entrances
1
0.54
0.43
0.00
31,953
2
0.54
0.85
0.00
87,953
4
Balconies
1
0.49
0.00
0.00
38,115
2
1.96
0.44
0.00
301,617
3
1.96
0.00
0.00
193,116
5
Gutters and
downspouts 1
0.72
0.00
0.00
16,290 The kind and the method of repair were accepted
on the basis of virtual status. The calculation data was Table 2. WUB calculated based on input data for 5 buildings Table 2. WUB calculated based on input data for 5 buildings
Build
ing
Building assessment against criterion
Pu
[m2]
WUB
[pt]
K1
[%]
K2
[pt]
K3
[kWh/
m2year]
1
47.66
2.40
172.70
4017.2 40.03
2
50.96
1.95
143.12
4484.0 35.70
3
51.03
2.36
173.96
2862.5 35.80
4
45.58
2.63
172.87
2700.4 43.16
5
43.16
2.63
151.79
2703.0 46.18 900 R. Bucoñ, A. Sobodka. Decision-making model for choosing residential building repair variants Table 8. 3. Model application example Details of the repair variants generated (solution 1)
Building Repair Variant
Repair description
K [PLN]
1
1
3
Façade painting
67,053
3
1
Vestibule renovation
31,953
5
1
Guttering replacement
16,290
6
1
Staircase door and
window replacement
66,617
2
1
2
Façade walls thermal
insulation
573,356
2
2
Roofing material
replacement
146,733
3
1
Vestibule renovation
18,922
4
3
Renovation of
balconies
153,482
3
1
3
Façade wall painting
47,144
3
1
Vestibule renovation
12,080
5
1
Guttering replacement
10,836
6
1
Staircase door and
window replacement
27,692 le 8. Details of the repair variants generated (solution performed calculations, five repair solutions were ob-
tained. Each repair solution presented in Table 6 consists
of repair variants for 5 buildings considered. The solution
number 1 is the mostly preferred due to the best WUB
increase relation to the costs (Table 6). Repair solution number 1 exceeded the assumed re-
pair budget by PLN 18,144, providing the building use
value increase ∆WUB 21.06 points, with the found use
effectiveness factor EF of 4.66. To compare, the best re-
pair solution not exceeding the budget (3 in Table 5) al-
lows ∆ WUB 20.35 pt, with the EF factor 4.53. The repair solution 1 consists of over a dozen re-
pair variants, which are assigned to each of five build-
ings (Table 7). The description of repair variants presented in Table 7
together with their costs performance is shown in Table 8. For the sake of brevity, only four repair variants are pre-
sented for three of five buildings considered. In the second case out of the repair set assigned to
each building (Table 5 – example for building B1) the
ones were sought for which the largest building use value
increase of each building will be obtained. The calculations performed clearly prove that the
highest increase of building use value of 21.06 points for
the amount PLN 4,518,144 was achievable for the first
example, i.e. the repair variants included in the repair
solution were chosen from a set of all repair activities
proposed for the buildings being analysed. The cost of repair in a building is dependent on its Pu
usable area. Accordingly, the budget B of PLN 4,500,000
was divided pro rata between 5 buildings, thereupon
it was obtained for B1 = 1,078,147; B2 = 1,203,428;
B3 = 768,246; B4 = 724,741; B5 = 725,438. 3. Model application example 3
5
As a result of calculations performed, the most fa-
vourable repair solutions were generated for each out of
5 buildings (Table 9).i The second example shows other possible use of
the model. Pro rata division of budget applied for the
buildings and the choice of the most favourable repair
solutions for each of them allowed the lowest increase
of use value (calculated for all the buildings) that equals
18.87 points for the amount PLN 4,520,834. The total cost of repair solutions for five buildings
(Table 9) exceeded the assumed budget by PLN 20,834,
resulting in ∆WUB of 18.87 points. This value is a weight-
ed average, where the weights are the buildings’ total us-
able floor area (Pu). The fund use effectiveness factor EF
is 4.17. Chosen repair variants included in the repair solu-
tions presented in Table 9 are listed in Table 10. It has to be stressed, however, that the approach pre-
sented in the second example is more appropriate when
the buildings analysed are built with different construc-
tion technologies, since applying the first approach would
result in priority being given to certain material solutions
adopted in individual construction technologies. Table 6. Five best repair solutions
Solution
F
∆WUB [pt]
EF
K [PLN]
1
20.89
21.06
4.66
4,518,144
2
20.35
20.51
4.54
4,517,378
3
20.32
20.35
4.53
4,491,967
4
20.26
20.30
4.52
4,492,982
5
20.20
20.36
4.51
4,518,058 Conclusions The article presents a decision-making model for choos-
ing repair solutions for the most cost-effective scope of
repair in terms of the assessment criteria adopted. This
required the authors to solve five tasks which constituted
the model. At each step, an approach or methods were
proposed to solve the specific task. Table 7. Comparison of repair variants (solution 1) Table 7. Comparison of repair variants (solution 1)
Building
Repair/variant
K [PLN]
1
1/3, 3/1, 5/1, 6/1, 7/2, 12/1
349,305
2
1/2, 2/2, 3/1, 4/3, 5/1, 6/2, 7/1, 8/1,
9/2, 10/1, 11/1, 12/1, 14/1, 16/1
2,343,659
3
1/3, 3/1, 5/1, 6/1, 7/1, 9/1, 16/1
319,895
4
1/2, 2/2, 3/1, 5/1, 6/2, 8/1, 9/2, 10/2
879,638
5
1/2, 3/1, 5/1, 6/2, 7/1, 8/1, 9/2, 10/2,
11/1
625,647
Total cost
4,518,144 Table 9. Repair solutions for 5 buildings
Building
F
∆WUB [pt]
EF
K [PLN]
1
14.78
15.24
1.39
1,092,546
2
20.16
20.19
1.68
1,204,010
3
19.91
19.97
2.60
767,342
4
19.33
20.12
2.72
739,085
5
19.47
19.65
2.74
717,851
Total cost
4,520,834 Table 9. Repair solutions for 5 buildings Journal of Civil Engineering and Management, 2015, 21(7): 893–901 901 Table 10. Repair variants for 5 buildings
Building
Repair/variant
K [PLN]
1
2/2, 3/2, 4/2, 5/1, 6/1, 7/2, 8/1, 12/1, 13/1 1,092,546
2
1/1, 2/2, 3/2, 5/1, 6/2, 7/1, 8/1, 9/2, 10/1 1,204,010
3
1/1, 3/2, 4/1, 5/1, 6/2, 7/1, 16/1
767,342
4
1/1, 2/2, 3/1, 5/1, 6/2, 7/1, 9/2
739,085
5
1/2, 3/2, 5/1, 6/2, 7/1, 8/1, 9/2, 10/2, 13/1 717,851 Table 10. Repair variants for 5 buildings and Decision Making in Civil and Building Engineering,
14–16 June 2006, Montreal, Canada. 10 p. and Decision Making in Civil and Building Engineering,
14–16 June 2006, Montreal, Canada. 10 p. Lounis, Z.; Vanier, D. J. 2000. A multiobjective and stochas-
tic system for building maintenance management, Journal
of Computer-Aided Civil and Infrastructure Engineering
15(5): 320–329. http://dx.doi.org/10.1111/0885-9507.00196
i
bi
k
h
k
ł
2003 Niezabitowska, E.; Kucharczyk-Brus, B.; Masły, D. 2003. Building utility value. Hamburg: Verlag Dashofer Com-
pany. 50 p. Orłowski, Z.; Szklennik, N. 2011. Scope of building moderni-
zation – as a result of diagnostic analysis of facility, Civil
and Environmental Engineering 2: 353–360. The model developed becomes a key part of the need
for strategic planning in building management. References Perng, Y. H.; Juan, Y. K.; Hsu, H. S. 2007. Genetic algorithm-
based decision support for the restoration budget alloca-
tion of historical buildings, Building and Environment
42(2): 770–778. http://dx.doi.org/10.1016/j.buildenv.2005.09.009 Alchimoviene, J.; Raslanas, S. 2011. Sustainable renovation
and evaluation of block of multi-apartment house, in
Proc. of the 8th International Conference “Environmental
Engineering”, Selected Papers, 19–20 May 2011, Vilnius,
Lithuania, 835–841. http://dx.doi.org/10.1016/j.buildenv.2005.09.009 Preiser, W. F. E. 1995. Post-occupancy evaluation: how to make
buildings work better, Facilities 13(11): 19–28. http://dx.doi.org/10.1108/02632779510097787 Bucoń, R.; Sobotka, A. 2012. Decision making model for selec-
tion of residential building renovation solutions, Scientific
Journals of UT Rzeszow 283(59): 57–64. Preiser, W. F. E.; Vischer, J. C. 2005. Assessing building per-
formance. 1st ed. USA: Elsevier Butterworth-Heinemann. 243 p. Caccavelli, D.; Gugerli, H. 2002. TOBUS – a European diagno-
sis and decision-making tool for Office building upgrad-
ing, Energy and Buildings 34(2): 113–119. http://dx.doi.org/10.1016/S0378-7788(01)00100-1 Real Estate Management Act of 21 August 1997, Journal of
Law, No 261/2004 with changes (in Polish). Reed, R.; Wilkinson, S.; Bilos, A.; Werner Schulte, K. 2011. A
comparison of international sustainable building tools –
an update, in Proc. of the 17th Annual Pacific Rim Real
Estate Society Conference, 16–19 January 2011, Gold
Coast, Australia. 16 p. Chen, G. Z. 2006. The assessment of building façade systems. IDCOP – Innovation in Design, Construction & Opera-
tion of Buildings for People 2006. Research Report. 8 p. Jaskowski, P.; Biruk, S.; Bucon, R. 2010. Assessing contrac-
tor selection criteria weights with fuzzy AHP method ap-
plication in group decision environment, Automation in
Construction 19(2): 120–126. http://dx.doi.org/10.1016/j.autcon.2009.12.014 Roderick, Y.; McEwan, D.; Wheatley, C.; Alonso, C. 2009. Comparison of energy performance assessment between
LEED, BREEAM and GREEN STAR, in Proc. of the 11th
International IBPSA Conference (IBPSA 2009), 27–30
July 2009, Glasgow, Scotland, 1167–1176. Juan, Y. K.; Kim, J. H.; Roper, K.; Lacouture, D. C. 2009. GA-based decision support system for housing condition
assessment and refurbishment strategies, Automation in
Construction 18(4): 394–401. http://dx.doi.org/10.1016/j.autcon.2008.10.006 Rosenfeld, Y.; Shohet, I. M. 1999. Decision support model
for semi-automated selection of renovation alternatives,
Automation in Construction 8(4): 503–510. http://dx.doi.org/10.1016/S0926-5805(98)00097-1i Kaklauskas, A.; Zavadskas, E. K.; Raslanas, S. 2005. Multi-
variant design and multiple criteria analysis of building
refurbishments, Energy and Buildings 37(4): 361–372. http://dx.doi.org/10.1016/j.enbuild.2004.07.005 Rutkowski, L. 2006. Methods and techniques of artificial intel-
ligence. Warsaw: PWN Scientific Publishing. 416 p.i Takagi, T.; Sugeno, M. 1985. Conclusions It can also
be used as a tool supporting the administrator in multiple
criteria building appraisal and the choice of the optimal
repair solution bearing in mind the financial constraints. Pan, N. F. 2008. Fuzzy AHP approach for selecting the suitable
bridge construction method, Automation in Construction
17(8): 958–965. http://dx.doi.org/10.1016/j.autcon.2008.03.005 Pater, S.; Magiera, J. 2011. Assessment of the energy demand
of a residential building using two independent compu-
tional programs, Technical Transactions 10: 165–184. References Fuzzy identification of systems
and its applications of modeling and control, IEEE Trans-
actions on Systems, Man & Cybernetics 15(1): 116–132. http://dx.doi.org/10.1109/TSMC.1985.6313399 Kasprowicz, T. 2005. Modelling of complex small buildings
operation and maintenance, in Proc. of the 9th Interna-
tional Conference on “Inspection, Appraisal – Repairs
and Maintenance of Structures”, 19–21 October 2005,
Fuzhou, China, 297–304. Vilhena, A.; Pedro, J. B.; Brito, J. 2011. Comparison of methods
used in European countries to assess building condition,
in Proc. of the 12th DBMC – International Conference on
Durability of Building Materials and Components, 12–15
April 2011, Porto, Portugal, 1267–1273. Langevine, R.; Allouche, M.; AbouRizk, S. 2006. Decision sup-
port tool for the maintenance management of buildings, in
Proc. of the Joint International Conference on Computing Robert BUCOŃ. PhD at Lublin University of Technology, Faculty of Civil Engineering and Architecture, Department of Construc-
tion Project Engineering in Poland. Academic degree: PhD in construction from Lublin University of Technology (2013). Author
of 23 scientific articles. Research interests include construction technology and organisation, properties management, simulation
modelling and multiple criteria decision making, expert systems, operation research. Robert BUCOŃ. PhD at Lublin University of Technology, Faculty of Civil Engineering and Architecture, Department of Construc-
tion Project Engineering in Poland. Academic degree: PhD in construction from Lublin University of Technology (2013). Author
of 23 scientific articles. Research interests include construction technology and organisation, properties management, simulation
modelling and multiple criteria decision making, expert systems, operation research. Anna SOBOTKA. Professor at AGH University of Science and Technology in Cracow, Faculty of Mining and Geoengineering,
Department of Geomechanics, Construction and Geotechnics in Poland. Academic degrees: PhD in construction from Warsaw Uni-
versity of Technology and DSc from Poznan University of Technology (2001). Author of about 200 scientific articles. Research
interests include construction technology and organisation, project management, construction logistics management and sustainable
development in construction, properties management, simulation modelling and multiple criteria decision making.
|
https://openalex.org/W4213423767
|
https://www.frontiersin.org/articles/10.3389/fcimb.2022.839435/pdf
|
English
| null |
Alterations of Gut Mycobiota Profiles in Adenoma and Colorectal Cancer
|
Frontiers in cellular and infection microbiology
| 2,022
|
cc-by
| 6,541
|
Alterations of Gut Mycobiota Profiles
in Adenoma and Colorectal Cancer Renyuan Gao 1†, Kai Xia 1†, Minkang Wu 1†, Hui Zhong 2†, Jing Sun 1†, Yin Zhu 1,
Linsheng Huang 2, Xiaocai Wu 1, Lu Yin 1, Rong Yang 2*, Chunqiu Chen 1*
and Huanlong Qin 1* 1 Diagnostic and Treatment Center for Refractory Diseases of Abdomen Surgery, Department of General Surgery, Shanghai
Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, China, 2 Department of Pediatrics, Shanghai Tenth
People’s Hospital, Tongji University School of Medicine, Shanghai, China Reviewed by: Reviewed by:
Abbas Yadegar,
Shahid Beheshti University of Medical
Sciences, Iran
Siok-Fong Chin,
National University of Malaysia,
Malaysia *Correspondence:
Rong Yang
leexuechun1@126.com
Chunqiu Chen
chenchunqiu6@126.com
Huanlong Qin
qinhuanlong@126.com *Correspondence:
Rong Yang
leexuechun1@126.com
Chunqiu Chen
chenchunqiu6@126.com
Huanlong Qin
qinhuanlong@126.com
†These authors have contributed
equally to this work and share
first authorship †These authors have contributed
equally to this work and share
first authorship Specialty section:
This article was submitted to
Microbiome in Health and Disease,
a section of the journal
Frontiers in Cellular and
Infection Microbiology
Received: 20 December 2021
Accepted: 25 January 2022
Published: 24 February 2022 Specialty section:
This article was submitted to
Microbiome in Health and Disease,
a section of the journal
Frontiers in Cellular and
Infection Microbiology INTRODUCTION Colorectal cancer is one of the most common digestive tract cancers worldwide that threatens the
life of millions of human beings every year (Siegel et al., 2020). The increasing trend of morbidity
and poor prognosis of early-onset colorectal cancer was another novel challenge observed by the
latest epidemiology survey (Peters et al., 2015; Akimoto et al., 2020). Massive public health resources
and attention have been paid to the prevention and early detection of colorectal cancer (CRC) to
reduce the enormous consumption of medical resources and improve the clinical prognosis in
developed and developing countries. However, many factors, such as obesity, high-fat diet,
sedentary behavior, genetics, and diabetes, acted as evil backstage manipulators to promote the
occurrence of CRC (Han et al., 2014; Simons et al., 2014; Zhang et al., 2015; Dabrowski et al., 2016;
Keum and Giovannucci, 2019). Of note, the gut microbiota was considered as one of the most Received: 20 December 2021
Accepted: 25 January 2022
Published: 24 February 2022 ORIGINAL RESEARCH
published: 24 February 2022
doi: 10.3389/fcimb.2022.839435 Alterations of Gut Mycobiota Profiles
in Adenoma and Colorectal Cancer
Renyuan Gao 1†, Kai Xia 1†, Minkang Wu 1†, Hui Zhong 2†, Jing Sun 1†, Yin Zhu 1,
Linsheng Huang 2, Xiaocai Wu 1, Lu Yin 1, Rong Yang 2*, Chunqiu Chen 1*
and Huanlong Qin 1* Keywords: gut mycobiota, metagenomic sequencing, microbial network, diagnostic model, colorectal cancer Accumulating evidence indicates that gut microbiota dysbiosis contributes to colorectal
cancerandadenoma.However,afewstudiesrevealedthealteredgutmycobiotaarchitecture
in colorectal cancer. The present study characterized the gut mycobiota profiles in adenoma
and colorectal cancer patients by metagenomic sequencing. Malassezia restricta increased,
while Leucoagaricus_sp_SymCcos and fungal_sp_ARF18 significantly decreased in
adenoma. Phanerochaete_chrysosporium, Lachancea_waltii, and Aspergillus_rambellii
were the top 3 fungi that were significantly enriched in colorectal cancer, while
Candida_versatilis, Pseudocercospora_pini_densiflorae, and Candida_sp_JCM_15000
were dominant in the healthy controls. Thirteen fungi, ranked as critical biomarkers in
diagnosing colorectal cancer, showed positive associations among all samples. Lachancea_waltii and Phanerochaete_chrysosporium showed the most significant
association within CRC. The values of area under the receiver-operating characteristics
curve (AUROC) of selected 13 mycobiota were 0.926 in the training model and 0.757 in the
10-fold validation model. Our study provided a reliable investigation of the alterations of gut
mycobiota in the development of colorectal cancer and established a convincing diagnostic
model for colorectal cancer, which mightimprove thetreatmentstrategy for colorectal cancer
in the future. Edited by:
Edwin Ramos Manuel,
City of Hope, United States Edited by:
Edwin Ramos Manuel,
City of Hope, United States Edited by:
Edwin Ramos Manuel,
City of Hope, United States Sample Collection and
Metagenomic Sequencing Fecal samples were obtained from all subjects, transported to the
lab, and stored immediately at −80°C. The details of DNA
extraction and metagenomic sequencing were described
previously (Gao et al., 2021). Briefly, genomic DNA was
extracted, and libraries were established according to the
Illumina manifestation instruction. Next, raw reads were
preprocessed and filtered to exclude adaptor contaminated
reads and low-quality reads. Finally, an average of 93.3% of
high-quality reads was obtained as the clean reads for
further analysis. Although the mycobiota only accounted for less than 0.1% of
the number of total microorganisms in the gastrointestinal tract,
they acted as essential immunoregulators for microenvironment
homeostasis and remote organs (Rizzetto et al., 2014; Underhill
and Iliev, 2014; Halwachs et al., 2017). Alterations of fungal
composition were likely to cause immune dysfunction and
mucosal barrier impairment, triggering an outbreak of systemic
disorders (Iliev and Leonardi, 2017). For instance, the fungi
Candida, such as Candida tropicalis and Candida glabrata, were
abundant in inflammatory disease (Liguori et al., 2016; Richard
and Sokol, 2019). Malassezia sympodialis and Saccharomyces
cerevisiae were also enriched in inflammatory bowel disease
(Sokol et al., 2016). Fungal dysbiosis was also prevalent during
carcinogenesis. We previously observed an increased proportion
of Trichosporon spp. and Malassezia spp. in the fecal samples of
colorectal cancer by ITS sequencing (Gao et al., 2017b). Recently,
a larger cohort study based on metagenomic sequencing found a
significantly increased relative abundance of Malasseziomycetes
and decreased proportion of Saccharomycetes in colorectal
cancer (Coker et al., 2019). However, the gut mycobiota
composition was affected by many factors, such as diet,
antibiotics, and disease state. The demonstration of gut
mycobiota alteration of different background patients and
accurate taxonomic characterization was also needed for the
comprehensive analysis of colorectal cancer. Clinical Characteristics of Enrolled
Patients and Healthy Controls Clinical Characteristics of Enrolled
Patients and Healthy Controls Data Access The metagenomic sequence data sets have been deposited in the
NCBI Sequence Read Archive (SRA) with accession numbers
PRJNA706060 and PRJNA514108 (Gao et al., 2021). Taxonomic Annotation and
Statistical Analysis The clean reads were assigned to microbial taxa by using the
k-mer-associated algorithms as described before (Gao et al.,
2021). Gene sequences were constructed by SOAPalign2.21. The relative abundances of genes were generated following Qin
et al. (2014) Random forest (randomForest package in R) was
applied to build the classifier based on the relative abundance of
fungal species. SparCC was used to construct the associations
among different fungal species. Linear discriminant analysis
effect size (LEfSe) was used to identify the significantly
dominated fungi in each group (Segata et al., 2011). Only two-
sided p-values <0.05 were displayed in the network. The
predictive model for early detection of colorectal cancer was
estimated by 10-fold cross-validation. The non-parametric
Wilcoxon test was used to analyze different taxonomic levels of
fungi. The Benjamini–Hochberg method was used for adjustment
for multiple comparisons. The adjusted p-value (false discovery
rate, FDR) <0.05 was considered statistically significant. Here, we presented a systemic analysis of gut mycobiota in
colorectal cancer, adenoma, and healthy controls with a
convincing sample size by metagenomic sequence. In addition,
we compared the diversity index of gut mycobiota in the three
groups and characterized the signatures of gut mycobiota in
colorectal cancer at different taxonomic levels by metagenomic
sequencing. Finally, we established a diagnosis panel by selecting
important fungal biomarkers ranked by random forest, which
might be helpful in the early detection of colorectal cancer in the
clinical setting. Citation: Gao R, Xia K, Wu M, Zhong H, Sun J,
Zhu Y, Huang L, Wu X, Yin L, Yang R,
Chen C and Qin H (2022) Alterations of
Gut Mycobiota Profiles in Adenoma
and Colorectal Cancer. Front. Cell. Infect. Microbiol. 12:839435. doi: 10.3389/fcimb.2022.839435 February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org Gut Mycobiota in Colorectal Cancer Gao et al. valuable and controllable carcinogens in the occurrence and
development of CRC recently (Gao et al., 2017a; Kang and
Martin, 2017). and healthy controls and the included and excluded criteria were
described previously (Gao et al., 2021). Briefly, patients who had
exposure to antibiotics, probiotics, and prebiotics within 1
month were excluded. Patients who had gastrointestinal
surgery history or diagnosed with acute or chronic diarrhea
and hepatitis were also excluded in the present study. All the
individuals provided informed consent. The Ethics Committee of
Shanghai Tenth People’s Hospital approved the study protocol. All the procedures performed during the study followed the
Declaration of Helsinki and its later amendments. Bacteria, which accounted for 99% of all the microorganisms,
dominated and functioned in the gut to maintain the whole
body’s health. Many clinical samples and exquisitely designed
animal experiments provided solid evidence on the carcinogenic
roles of certain enriched bacteria, such as Fusobacterium
nucleatum and pks+ Escherichia coli, in CRC patients. The
sophisticated mechanisms of the signal transduction pathways
triggered by these harmful carcinogens in the gut were also
revealed during the past few years. However, a limited number of
studies focused on the roles of mycobiota in colorectal cancer. Enrollment of Patients Colonic adenoma and colorectal cancer (CRC) patients included
in the present study were enrolled at Shanghai Tenth People’s
Hospital. The detailed characteristics of all the enrolled patients y
A total of 71 CRC patients, 63 adenoma patients, and 91 healthy
controls were finally included in the study, as described before February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org Gut Mycobiota in Colorectal Cancer Gao et al. (Gao et al., 2021). All these individuals in the three groups were
comparable regarding sex, age, and BMI (p > 0.05) (Table 1). Most of the CRC patients were diagnosed with rectal cancer. CRC patients with stages II and III, categorized by the American
Joint Committee on Cancer staging system, accounted for 57%. The KRAS gene mutation rate was 49.3% in all CRC patients. healthy controls by LEfSe, respectively (Figure 3A). Malassezia_restricta (p = 0.0014, FDR = 0.17) was enriched in the
adenoma group at the species level, but no statistical difference was
observed after statistical correction. Only two fungi, namely,
Leucoagaricus_sp_SymCcos (p = 6.79 * 10−6, FDR = 0.0077) and
fungal_sp_ARF18(p=5.13*10−5,FDR= 0.029),showedsignificant
decreased relative abundance in adenoma compared with healthy
controls (Figure 3B). Blumeria dominated in CRC, while
Madurella was enriched in adenoma by LEfSe (Figure 3C). Penicillium_fuscoglaucum (p = 1.08 * 10−6, FDR = 0.0012) and
Blumeria_graminis (p = 2.68 * 10−5, FDR = 0.015) were found
enriched in the CRC with a statistical difference when compared
with adenoma by Wilcoxon test (Figure 3D). Diagnostic Model Based on Gut Mycobiota
for Early Detection of Colorectal Cancer Diagnostic Model Based on Gut Mycobiota
for Early Detection of Colorectal Cancer Diagnostic Model Based on Gut Mycobiota
for Early Detection of Colorectal Cancer
To identify the most important mycobiota in colorectal cancer,
we used random forest to rank all the different mycobiota based To identify the most important mycobiota in colorectal cancer,
we used random forest to rank all the different mycobiota based TABLE 1 | The characteristics of the studied subjects in the present study (mean ± standard deviation). Colorectal cancer
Adenoma
Healthy controls
p-value
No. of individuals
71
63
91
Male (%)
42 (59.15)
34 (53.97)
38 (41.76)
0.07
Age (years)
61.85 ± 10.96
63.22 ± 7.29
60.23 ± 5.06
0.06
BMI
22.96 ± 3.85
23.81 ± 3.03
23.32 ± 1.97
0.11
A/T/D/S/Ra
16/5/2/8/40
/
/
/
Stage I/II/III/IV
9/30/27/5
/
/
/
KRAS mutation (%)
35 (49.3%)
/
/
/
CEA (ng/ml)b
25.05 ± 14.52
/
/
/
AFP (ng/ml)
2.99 ± 1.22
/
/
/
CA153 (U/ml)
10.37 ± 4.66
/
/
/
CA-125 (U/ml)
16.98 ± 19.91
/
/
/
CA199 (U/ml)b
34.59 ± 15.38
/
/
/
CA724 (U/ml)b
6.68 ± 1.66
/
/
/
CA50 (IU/ml)b
16.30 ± 5.61
/
/
/
CEA, carcinoembryonic antigen; AFP, alpha-fetoprotein. aOne patient had two cancers in both ascending colon and rectum, which was counted in both ascending colon cancer and rectal cancer: A, ascending colon; T, transversal colon;
D, descending colon; S, sigmoid colon; R, rectum. bMean ± standard error of mean (SEM). TABLE 1 | The characteristics of the studied subjects in the present study (mean ± standard deviation). Colorectal cancer
Adenoma
Healthy controls
p-value
No. of individuals
71
63
91
Male (%)
42 (59.15)
34 (53.97)
38 (41.76)
0.07
Age (years)
61.85 ± 10.96
63.22 ± 7.29
60.23 ± 5.06
0.06
BMI
22.96 ± 3.85
23.81 ± 3.03
23.32 ± 1.97
0.11
A/T/D/S/Ra
16/5/2/8/40
/
/
/
Stage I/II/III/IV
9/30/27/5
/
/
/
KRAS mutation (%)
35 (49.3%)
/
/
/
CEA (ng/ml)b
25.05 ± 14.52
/
/
/
AFP (ng/ml)
2.99 ± 1.22
/
/
/
CA153 (U/ml)
10.37 ± 4.66
/
/
/
CA-125 (U/ml)
16.98 ± 19.91
/
/
/
CA199 (U/ml)b
34.59 ± 15.38
/
/
/
CA724 (U/ml)b
6.68 ± 1.66
/
/
/
CA50 (IU/ml)b
16.30 ± 5.61
/
/
/
CEA, carcinoembryonic antigen; AFP, alpha-fetoprotein. Alterations of Mycobiota Richness
and Diversity in Adenoma and
Colorectal Cancer The number of species and a-diversity of gut mycobiota were
compared in CRC, adenoma, and HC groups. No significant
difference was observed among the three groups (p > 0.05)
(Figures 1A, B). Principal coordinate analysis (PCoA) was also
performed to evaluate b-diversity. PCoA1 and PCoA2 accounted
for 24.1% and 12.6% of the variance, respectively (Figure 1C). Analysis of similarity did not show statistically significant
differences among the three groups. The alteredgutmycobiotaprofilesofCRCwerealsoevaluated,and
a total of 39 fungi were found with statistical differences between CRC
and healthy controls (Figure 4A). Phanerochaete_chrysosporium,
Lachancea_waltii, and Aspergillus_rambellii were the top 3 fungi
with the most significant differences that were enriched in CRC
patients, while Candida_versatilis, Pseudocercospora_
pini_densiflorae, and Candida_sp_JCM_15000 were the top 3 fungi
significantly decreased in CRC patients. Gut Mycobiota Dysbiosis in Adenoma
and Colorectal Cancer Besides, we also evaluated the CRC-dominated fungi by LEfSe. Blumeria_graminis, Phanerochaete_chrysosporium, Sclerotinia_
homoeocarpa, Puccinia_psidii, Aspergillus_flavus, and
Entomophthora_muscae were the main six enriched fungi in the
CRC, while Penicillium_janthinellum, Naumovozyma_castellii,
Cutaneotrichosporon_arboriformis, Agaricus_bisporus,
Penicillium_paxilli, and fungal_sp_ARF18 were the top 6 fungi in
the healthy controls (Figure 4B). Interestingly, five of the top 6
dominatedfungiatthethresholdofLDAscoreof3byLEfSewereall
identified as statistically different in CRC patients by Wilcoxon test. Compared with the healthy controls, the mycobiota taxonomic
profiles were analyzed at the phylum, genus, and species levels in
adenoma and colorectal cancer (Figures 2A–C). At the phylum
level, eight main phyla were finally identified in all samples. Mucoromycota and Ascomycota were the major mycobiota at the
phylum level in all samples. The relative abundances of
Mucoromycota were 45.52% in CRC, 44.94% in adenoma, and
47.16%inhealthy controls. The relative abundances ofAscomycota
were 38.54% in CRC, 39.77% in adenoma, and 36.37% in healthy
controls. No significant difference in the phyla was observed in the
three groups (Figure 2D). The ratios of Ascomycota/
Basidiomycota were also similar in the three groups (data not
shown). At the genus level, Anaeromyces and Phanerochaete were
the most significantly different genus enriched in adenoma and CEA, carcinoembryonic antigen; AFP, alpha-fetoprotein.
aOne patient had two cancers in both ascending colon and rectum, which was counted in both ascending colon cancer and rectal cancer: A, ascending colon; T, transversal colon;
D, descending colon; S, sigmoid colon; R, rectum.
bMean ± standard error of mean (SEM). CEA, carcinoembryonic antigen; AFP, alpha-fetoprotein. Diagnostic Model Based on Gut Mycobiota
for Early Detection of Colorectal Cancer aOne patient had two cancers in both ascending colon and rectum, which was counted in both ascending colon cancer and rectal cancer: A, ascending colon; T, transversal colon;
D, descending colon; S, sigmoid colon; R, rectum. bMean ± standard error of mean (SEM). February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org 3 Gut Mycobiota in Colorectal Cancer Gao et al. A A
C
B
FIGURE 1 | The mycobiota diversity comparison between colorectal cancer (CRC), adenoma, and healthy controls (HC). The number of species (A) and Shannon
index (B) were similar between the three groups. Principal coordinate analysis of the mycobiota in the three groups (C). C C A B B FIGURE 1 | The mycobiota diversity comparison between colorectal cancer (CRC), adenoma, and healthy controls (HC). The number of species (A) and Shannon
index (B) were similar between the three groups. Principal coordinate analysis of the mycobiota in the three groups (C). in CRC. Aspergillus_rambellii was positively associated with
Entomophthora_muscae (r = 0.65, p = 1.87 * 10−28), Aspergillus_
flavus (r = 0.65, p = 2.82 * 10−28), and Lachancea_waltii (r = 0.61, p =
1.25 * 10−24) in CRC. In adenoma, fungal_sp_ARF18 was positively
associated with Brettanomyces_anomalus (r = 0.53, p = 6.96 * 10−18). In the healthy controls, Metschnikowia_cubensis was positively
associated with Spraguea_lophii (r = 0.35, p = 4.42 * 10−8). on mean decreased accuracy. Taxomyces_andreanae,
Aspergillus_rambellii, Lachancea_waltii, fungal_sp_ARF18, and
Phanerochaete_chrysosporium were the top 5 mycobiota that
ranked as most essential markers (Figure 5A). Based on the
maximum value of area under the receiver-operating
characteristics curve (AUROC), 13 mycobiota in importance
ranking were selected as a novel diagnostic panel (Figure 5B). The AUROC of this panel in the testing model was 0.926 (95%
confidence interval: 0.853–0.999), the sensitivity was 78.6%, and
the specificity was 100% (Figure 5C). In the 10-fold cross-
validation, the AUROC was 0.757 (95% confidence interval:
0.651–0.862), and both the sensitivity and specificity were
71.4% (Figure 5D). We also evaluated the relative abundances of the key 13
mycobiota in different stages of CRC (Figure 6C). No statistical
differences of the mycobiota were found between the four stages
of CRC. Mycobiota Correlations and Stage-
Specific Distribution of Key Differed
Markers in Colorectal Cancer The gut mycobiota plays a vital role in maintaining the healthy
status of human beings. Our study presented the alteration of gut
mycobiota and established the early diagnosis for CRC based on
high-throughput sequencing, providing more sophisticated and
convincing evidence on the potential roles of gut mycobiota in
adenoma and CRC (Figure 7). Themycobiotacorrelationsofthekeymicrobiotaselectedabovewere
also evaluated in CRC, adenoma, and healthy controls. Interestingly,
all 13 mycobiota showed positive associations (Figures 6A, B). The
gutmycobiotain CRChadthemost intenseconnections,followedby
adenoma and healthy controls. Lachancea_waltii and
Phanerochaete_chrysosporium showed the most significant
association in CRC (r = 0.80, p = 1.55 * 10−51). Phanerochaete_
chrysosporium was also positively associated with Entomophthora_
muscae (r = 0.72, p = 6.00 * 10−38), Taxomyces_andreanae (r = 0.70,
p = 2.91 * 10−34), and Aspergillus_rambellii (r = 0.64, p = 1.03 * 10−27) Nowadays, more and more studies have begun investigating
the underestimated roles of gut mycobiota in colorectal cancer. Deciphering the mycobiota architecture was the first and
essential step to uncover their potential roles in the
occurrence and development of colorectal cancer. The altered
signatures of gut mycobiota in colon polyp or adenoma and February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org Gut Mycobiota in Colorectal Cancer Gao et al. A
C
D
B
FIGURE 2 | The taxonomy of gut mycobiota at the phylum (A), genus (B), and species (C) levels in colorectal cancer (CRC), adenoma, and healthy controls. The
comparisons of eight mycobiota at the phylum level in CRC, adenoma, and healthy controls (HC) (D). No significant changes were found between the three groups. D D B FIGURE 2 | The taxonomy of gut mycobiota at the phylum (A), genus (B), and species (C) levels in colorectal cancer (CRC), adenoma, and healthy controls. The
comparisons of eight mycobiota at the phylum level in CRC, adenoma, and healthy controls (HC) (D). No significant changes were found between the three groups. colorectal cancer were displayed by internal transcribed spacer
sequencing (Luan et al., 2015; Gao et al., 2017b). Opportunistic
fungi such as Trichosporon and Malassezia were found enriched
in CRC. However, after applying metagenomics sequencing,
more detailed information on fungi dysbiosis could be
obtained. Coker et al. identified Malasseziomycetes dominant
in CRC and fungal biomarker panel for CRC diagnosis, which
showed an excellent discriminative capacity (Coker et al.,
2019). The present study found several CRC-associated
mycobiota. Frontiers in Cellular and Infection Microbiology | www.frontiersin.org Mycobiota Correlations and Stage-
Specific Distribution of Key Differed
Markers in Colorectal Cancer For instance, Aspergillus, including Aspergillus
rambellii, Aspergillus ochraceoroseus, and Aspergillus flavus,
were significantly enriched in CRC. This was consistent with
a previously published study (Coker et al., 2019). Aspergillus flavus was reported to be involved in the production of
aflatoxin, targeting aryl hydrocarbon receptor to mediate the
expression of P450 to induce hepatocellular carcinoma process,
indicating that these species seemed to have an underestimated
relation with colorectal cancer (Sharma et al., 2021; Zhu et al.,
2021a). Debaryomyces fabryi was also significantly enriched in
CRC. A previous study demonstrated that Debaryomyces
dominated in inflamed mucosal tissues of Crohn’s disease
and impaired mucosal healing via myeloid-type I interferon–
CCL5 axis (Jain et al., 2021). Intestinal mucosal inflammation, a
detrimental consequence of antibiotics and Debaryomyces
outgrowth, was also associated with mycobiota dysbiosis in
the gut (Chiaro and Round, 2021). Whether Debaryomyces had February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org 5 Gut Mycobiota in Colorectal Cancer Gao et al. D
B
ant gut mycobiota in adenoma and healthy controls (A). The significant
k-sum test (B). The enriched gut mycobiota in colorectal cancer and healthy
n colorectal cancer and adenoma by Wilcoxon rank-sum test (D). FDR, false A
C
D
B
FIGURE 3 | The linear discriminant analysis effect size (LEfSe) analysis revealed dominant gut mycobiota in adenoma and healthy controls (A). The significa
alterations of two mycobiota between adenoma and healthy controls by Wilcoxon rank-sum test (B). The enriched gut mycobiota in colorectal cancer and h
controls based on LEfSe analysis (C). The significantly changed gut mycobiota between colorectal cancer and adenoma by Wilcoxon rank-sum test (D). FD
discovery rate. B A B B C
D
FIGURE 3 | The linear discriminant analysis effect size (LEfSe) analysis revealed dominant gut mycobiota in adenoma and healthy controls (A). The significant
alterations of two mycobiota between adenoma and healthy controls by Wilcoxon rank-sum test (B). The enriched gut mycobiota in colorectal cancer and healthy
controls based on LEfSe analysis (C). The significantly changed gut mycobiota between colorectal cancer and adenoma by Wilcoxon rank-sum test (D). FDR, false
discovery rate. C C C D D D D FIGURE 3 | The linear discriminant analysis effect size (LEfSe) analysis revealed dominant gut mycobiota in adenoma and healthy controls (A). The significant
alterations of two mycobiota between adenoma and healthy controls by Wilcoxon rank-sum test (B). Mycobiota Correlations and Stage-
Specific Distribution of Key Differed
Markers in Colorectal Cancer The enriched gut mycobiota in colorectal cancer and healthy
controls based on LEfSe analysis (C). The significantly changed gut mycobiota between colorectal cancer and adenoma by Wilcoxon rank-sum test (D). FDR, false
discovery rate. February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org Gut Mycobiota in Colorectal Cancer Gao et al. A
B
FIGURE 4 | The alteration of gut mycobiota signatures in colorectal cancer (CRC). The mycobiota profiles that were enriched in CRC and healthy controls by
Wilcoxon rank-sum test (A) and linear discriminant analysis effect size analysis (B). *p < 0.05; **p < 0.01. B
profiles that were enriched in CRC and healthy controls by B FIGURE 4 | The alteration of gut mycobiota signatures in colorectal cancer (CRC). The mycobiota profiles that were enriched in CRC and healthy controls by
Wilcoxon rank-sum test (A) and linear discriminant analysis effect size analysis (B). *p < 0.05; **p < 0.01. The potential reasons might be due to the limited culture
technology and the lack of a high-throughput sequencing
application in identifying candidate fungi. Entomophthora
muscae, a fungal pathogen, was also enriched in CRC in the
present study. This species was found to evade the nervous
system and modulate the behavior of Drosophila melanogaster,
but there was minimal evidence that demonstrated its role in
human disease, especially in cancer (Elya et al., 2018). However,
these findings also need to be confirmed in the future. Other
unidentified fungi in the present study had been reported to be
closely related to colon tumorigenesis. For example, Candida
albicans contributed to colon cancer by glycolysis in a close implication with colonic carcinogenesis was still
underestimated. We also noticed that Saccharomyces species,
including Saccharomyces paradoxus and Saccharomyces
mikatae, were also enriched in CRC. Saccharomyces consisted
of at least eight species, and some species had been regarded as
agents responsible for invasive infection (Enache-Angoulvant
and Hennequin, 2005). However, rare studies reported the
associations between S. paradoxus and S. mikatae in CRC. Of
note, we also found that fungal_sp_ARF18 was the only fungi
that was enriched in both adenoma and colorectal cancer
patients. The role of this fungi was still underestimated in
human health and disease so far. February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org 7 Gut Mycobiota in Colorectal Cancer Gao et al. Mycobiota Correlations and Stage-
Specific Distribution of Key Differed
Markers in Colorectal Cancer A
C
D
B
FIGURE 5 | The ranking of importance of gut mycobiota by mean decreased accuracy at the species level (A). The values of area under the curve (AUC) by different
variable number of gut mycobiota (B). The AUC ranked top when the corresponding variable number was 13. The AUC of the selected 13 gut mycobiota profiles for
predicting colorectal cancer in the training cohort (C) and 10-fold cross-validation (D). B A
B C D D C FIGURE 5 | The ranking of importance of gut mycobiota by mean decreased accuracy at the species level (A). The values of area under the curve (AUC) by different
variable number of gut mycobiota (B). The AUC ranked top when the corresponding variable number was 13. The AUC of the selected 13 gut mycobiota profiles for
predicting colorectal cancer in the training cohort (C) and 10-fold cross-validation (D). Candida versatilis, Candida aaseri, and Candida_sp_JCM_15000,
in CRC. Candida versatilis, a yeast resistant to salt, was used for
soy sauce fermentation (Ruan et al., 2019). Some salty food had
been indicated to be a strong risk factor associated with
colorectal cancer (Takachi et al., 2010). Therefore, we wonder macrophages, thus triggering the interleukin-22 secretion from
innate lymphoid cells (Zhu et al., 2021b). Nevertheless, the present study did not identify the significant
enrichment of C. albicans in CRC or adenoma. In contrast, we
found a considerable decrease of other Candida species, such as February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org Gut Mycobiota in Colorectal Cancer Gao et al. A
C
B
RE 6 | The 13 mycobiota network in colorectal cancer (CRC), adenoma, and healthy controls. All mycobiota showed positive correlations in the network (A). heatmap displayed positive relationships among the selected 13 gut mycobiota (B). The relative abundances of the 13 mycobiota in different stages (stages I, II,
d IV) of CRC (C). *p < 0.05. A
B B A C C FIGURE 6 | The 13 mycobiota network in colorectal cancer (CRC), adenoma, and healthy controls. All mycobiota showed positive correlations in the network (A). The heatmap displayed positive relationships among the selected 13 gut mycobiota (B). The relative abundances of the 13 mycobiota in different stages (stages I, II,
III, and IV) of CRC (C). *p < 0.05. values of gut mycobiota for colorectal cancer. FIGURE 7 | The conceptual figure to demonstrate the alterations of gut mycobiota in adenoma and colorectal cancer. The relative abundances of Malassezia
restricta increased, while Leucoagaricus_sp_SymCcos and fungal_sp_ARF18 significantly decreased in adenoma. Phanerochaete_chrysosporium, Lachancea_waltii,
and Aspergillus_rambellii were the top 3 fungi that were significantly enriched in colorectal cancer, while Candida_versatilis, Pseudocercospora_pini_densiflorae, and
Candida_sp_JCM_15000 were dominant in the healthy controls. FIGURE 7 | The conceptual figure to demonstrate the alterations of gut mycobiota in adenoma and colorectal cancer. The relative abundances of Malassezia
restricta increased, while Leucoagaricus_sp_SymCcos and fungal_sp_ARF18 significantly decreased in adenoma. Phanerochaete_chrysosporium, Lachancea_waltii,
and Aspergillus_rambellii were the top 3 fungi that were significantly enriched in colorectal cancer, while Candida_versatilis, Pseudocercospora_pini_densiflorae, and
Candida_sp_JCM_15000 were dominant in the healthy controls. FIGURE 7 | The conceptual figure to demonstrate the alterations of gut mycobiota in adenoma and colorectal cancer. The relative abundances of Malassezia
restricta increased, while Leucoagaricus_sp_SymCcos and fungal_sp_ARF18 significantly decreased in adenoma. Phanerochaete_chrysosporium, Lachancea_waltii,
and Aspergillus_rambellii were the top 3 fungi that were significantly enriched in colorectal cancer, while Candida_versatilis, Pseudocercospora_pini_densiflorae, and
Candida_sp_JCM_15000 were dominant in the healthy controls. DATA AVAILABILITY STATEMENT RY performed the visualization and interpretation of data. HQ
performed the sample sequencing and analysis. RG and HQ
designed and guided the whole study. All authors contributed to
the article and approved the submitted version. The datasets presented in this study can be found in online
repositories. The names of the repository/repositories and
accession number(s) can be found below: https://www.ncbi.nlm. nih.gov/sra, accession ID: PRJNA706060 and PRJNA514108. ETHICS STATEMENT This work was supported by grants from the National Natural
Science Foundation of China (No. 81972221), Training program
of the National Natural Science Foundation of China of Shanghai
Tenth People’s Hospital (SYGZRPY2017024), “Climbing” plan
of Shanghai Tenth People’s Hospital (2018SYPDRC030), and
Special Project of Clinical Research on Health Care Industry of
Shanghai Municipal Health Commission (20194Y0483). The studies involving human participants were reviewed and
approved by the Ethics Committee of Shanghai Tenth People’s
Hospital.Thepatients/participantsprovidedtheirwritteninformed
consent to participate in this study. Written informed consent was
obtained from the individual(s) for the publication of any
potentially identifiable images or data included in this article. Mycobiota Correlations and Stage-
Specific Distribution of Key Differed
Markers in Colorectal Cancer Moreover, we
deciphered the CRC-associated gut mycobiota at the species level
and their interactions in different statuses, which could
contribute to understanding the roles in colonic carcinogenesis. However, of course, a tremendous amount of effects and
extensive cooperation are needed to illustrate the gut
mycobiota mystery in colorectal cancer, especially the
mechanisms in the future. if there are any potential relations between the unproven
beneficial effect of C. versatilis and gut health. In addition,
Saccharomyces malanga, a yeast that functioned in the
fermentation of the traditional Chinese baijiu and rice wine,
was also elevated in healthy controls compared with CRC (Wang
et al., 2020). In conclusion, our study elucidated the dysbiosis signatures of
adenoma and colorectal cancer and demonstrated the diagnostic February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org 9 Gut Mycobiota in Colorectal Cancer Gao et al. FIGURE 7 | The conceptual figure to demonstrate the alterations of gut mycobiota in adenoma and colorectal cancer. The relative abundances of Malassezia
restricta increased, while Leucoagaricus_sp_SymCcos and fungal_sp_ARF18 significantly decreased in adenoma. Phanerochaete_chrysosporium, Lachancea_waltii,
and Aspergillus_rambellii were the top 3 fungi that were significantly enriched in colorectal cancer, while Candida_versatilis, Pseudocercospora_pini_densiflorae, and
Candida_sp_JCM_15000 were dominant in the healthy controls. REFERENCES 41, 1559–1568. doi:
10.1086/497832 Gao, R., Gao, Z., Huang, L., and Qin, H.. (2017a). Gut Microbiota and Colorectal
Cancer. Eur. J. Clin. Microbiol. Infect. Dis. 36, 757–769. doi: 10.1007/s10096-
016-2881-8 Sokol, H., Leducq, V., Aschard, H., Pham, H. P., Jegou, S., Landman, C., et al. (2016). Fungal Microbiota Dysbiosis in IBD. Gut 66 (6), 1039–1048. doi:
10.1136/gutjnl-2015-310746 Gao, R., Kong, C., Li, H., Huang, L., Qu, X., Qin, N., et al. (2017b). Dysbiosis
Signature of Mycobiota in Colon Polyp and Colorectal Cancer. Eur. J. Clin. Microbiol. Infect. Dis. 36, 2457–2468. doi: 10.1007/s10096-017-3085-6 Takachi, R., Inoue, M., Shimazu, T., Sasazuki, S., Ishihara, J., Sawada, N., et al. (2010). Consumption of Sodium and Salted Foods in Relation to Cancer and
Cardiovascular Disease: The Japan Public Health Center-Based Prospective
Study. Am. J. Clin. Nutr. 91, 456–464. doi: 10.3945/ajcn.2009.28587 Gao, R., Zhu, Y., Kong, C., Xia, K., Li, H., Zhu, Y., et al. (2021). Alterations,
Interactions, and Diagnostic Potential of Gut Bacteria and Viruses in
Colorectal Cancer. Front. Cell Infect. Microbiol. 11, 657867. doi: 10.3389/
fcimb.2021.657867 tudy. Am. J. Clin. Nutr. 91, 456–464. doi: 10.3945/ajcn.2009.2858 Underhill, D. M., and Iliev, I. D. (2014). The Mycobiota: Interactions Between
Commensal Fungi and the Host Immune System. Nat. Rev. Immunol. 14, 405–
416. doi: 10.1038/nri3684 Halwachs, B., Madhusudhan, N., Krause, R., Nilsson, R. H., Moissl-Eichinger, C.,
Hogenauer, C., et al. (2017). Critical Issues in Mycobiota Analysis. Front. Microbiol. 8, 180. doi: 10.3389/fmicb.2017.00180 Wang, C., Tang, J., and Qiu, S. (2020). Profiling of Fungal Diversity and
Fermentative Yeasts in Traditional Chinese Xiaoqu. Front. Microbiol. 11,
2103. doi: 10.3389/fmicb.2020.02103 Han, X., Stevens, J., Truesdale, K. P., Bradshaw, P. T., Kucharska-Newton, A.,
Prizment, A. E., et al. (2014). Body Mass Index at Early Adulthood, Subsequent
Weight Change and Cancer Incidence and Mortality. Int. J. Cancer 135, 2900–
2909. doi: 10.1002/ijc.28930 Zhang, X., Wu, K., Giovannucci, E. L., Ma, J., Colditz, G. A., Fuchs, C. S., et al. (2015). Early Life Body Fatness and Risk of Colorectal Cancer in U.s. Women
and Men-Results From Two Large Cohort Studies. Cancer Epidemiol. Biomarkers Prev. 24, 690–697. doi: 10.1158/1055-9965.EPI-14-0909-T Iliev, I. D., and Leonardi, I. (2017). Fungal Dysbiosis: Immunity and Interactions
at Mucosal Barriers. Nat. Rev. Immunol 17 (10), 635–646. doi: 10.1038/
nri.2017.55 Zhu, Q., Ma, Y., Liang, J., Wei, Z., Li, M., Zhang, Y., et al. (2021a). AHR Mediates
the Aflatoxin B1 Toxicity Associated With Hepatocellular Carcinoma. Signal
Transduct Target Ther. 6, 299. REFERENCES Rizzetto, L., De Filippo, C., and Cavalieri, D. (2014). Richness and Diversity of
Mammalian Fungal Communities Shape Innate and Adaptive Immunity in
Health and Disease. Eur. J. Immunol. 44, 3166–3181. doi: 10.1002/
eji.201344403 Akimoto, N., Ugai, T., Zhong, R., Hamada, T., Fujiyoshi, K., Giannakis, M., et al. (2020). Rising Incidence of Early-Onset Colorectal Cancer - a Call to Action. Nat. Rev. Clin. Oncol 18 (4), 230–243. doi: 10.1038/s41571-020-00445-1 (2020). Rising Incidence of Early-Onset Colorectal Cancer - a Call to Action. Nat. Rev. Clin. Oncol 18 (4), 230–243. doi: 10.1038/s41571-020-00445-1 Ruan, L., Meng, M., Wang, C., and Hou, L.. (2019). Draft Genome Sequence of
Candida Versatilis and Osmotolerance Analysis in Soy Sauce Fermentation. J. Sci. Food Agric. 99, 3168–3175. doi: 10.1002/jsfa.9532 Chiaro, T., and Round, J. L. (2021). Fungi Prevent Intestinal Healing. Science 371
(6534), 1102–1103. doi: 10.1126/science.abg6017 Segata, N., Izard, J., Waldron, L., Gevers, D., Miropolsky, L., Garrett, W. S., et al. (2011). Metagenomic Biomarker Discovery and Explanation. Genome Biol. 12,
R60. doi: 10.1186/gb-2011-12-6-r60 Coker, O. O., Nakatsu, G., Dai, R. Z., Wu, W. K. K., Wong, S. H., Ng, S. C., et al. (2019). Enteric Fungal Microbiota Dysbiosis and Ecological Alterations in
Colorectal Cancer. Gut 68, 654–662. doi: 10.1136/gutjnl-2018-317178 Sharma, P. C., Sharma, D., Sharma, A., Bhagat, M., Ola, M., Thakur, V. K., et al. (2021). Recent Advances in Microbial Toxin-Related Strategies to Combat
Cancer. Semin. Cancer Biol. S1044-579X (21), 00201–7. doi: 10.1016/
j.semcancer.2021.07.007 Dabrowski, M., Szymanska-Garbacz, E., Miszczyszyn, Z., Derezinski, T., and
Czupryniak, L.. (2016). Risk Factors for Cancer Development in Type 2
Diabetes: A Retrospective Case-Control Study. BMC Cancer 16, 785. doi:
10.1186/s12885-016-2836-6 Siegel, R. L., Miller, K. D., Goding Sauer, A., Fedewa, S. A., Butterly, L. F.,
Anderson, J. C., et al. (2020). Colorectal Cancer Statistics, 2020. CA Cancer J. Clin 70 (3), 145–164. doi: 10.3322/caac.21601 Elya, C., Lok, T. C., Spencer, Q. E., McCausland, H., Martinez, C. C., and Eisen, M.. (2018). Robust Manipulation of the Behavior of Drosophila Melanogaster by a
Fungal Pathogen in the Laboratory. Elife 7, e34414. doi: 10.7554/eLife.34414 Simons, C. C., van den Brandt, P. A., Stehouwer, C. D., van Engeland, M., and
Weijenberg, M. P.. (2014). Body Size, Physical Activity, Early-Life Energy
Restriction, and Associations With Methylated Insulin-Like Growth Factor-
Binding Protein Genes in Colorectal Cancer. Cancer Epidemiol. Biomark. Prev. 23, 1852–1862. doi: 10.1158/1055-9965.EPI-13-1285 Enache-Angoulvant, A., and Hennequin, C. (2005). Invasive Saccharomyces
Infection: A Comprehensive Review. Clin. Infect. Dis. AUTHOR CONTRIBUTIONS We extend our thanks to Qian Xu, Zhan Cao, and Chunyan Wu
of Shanghai Realbio Biotechnology Co., Ltd. We thank all the
members of the Diagnostic and Treatment Center for Refractory
Diseases of Abdomen Surgery, Department of General Surgery,
Tongji University School of Medicine. We also want to thank all
the participants for providing their samples. HQ, CC, and RY take responsibility for the integrity of the work
as a whole, from inception to the publication of the article. RG
wrote the manuscript. RG, KX, YZ, HZ, and MW performed the
data check and analysis. YZ, LH, XW, JS, and LY helped collect
all the subject information and samples. RG, KX, YZ, HZ, and February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org Frontiers in Cellular and Infection Microbiology | www.frontiersin.org
10 Gut Mycobiota in Colorectal Cancer Gao et al. REFERENCES doi: 10.1038/s41392-021-00713-1 Jain, U., Ver Heul, A. M., Xiong, S., Gregory, M. H., Demers, E. G., Kern, J. T., et al. (2021). Debaryomyces is Enriched in Crohn’s Disease Intestinal Tissue and
Impairs Healing in Mice. Science 371, 1154–1159. doi: 10.1126/
science.abd0919 Zhu, Y., Shi, T., Lu, X., Xu, Z., Qu, J., Zhang, Z., et al. (2021b). Fungal-Induced
Glycolysis in Macrophages Promotes Colon Cancer by Enhancing Innate
Lymphoid Cell Secretion of IL-22. EMBO J. 40(11), e105320. doi: 10.15252/
embj.2020105320 Kang, M., and Martin, A. (2017). Microbiome and Colorectal Cancer: Unraveling
Host-Microbiota Interactions in Colitis-Associated Colorectal Cancer
Development. Semin. Immunol. 32, 3–13. doi: 10.1016/j.smim.2017.04.003 Conflict of Interest: The authors declare that the research was conducted in the
absence of any commercial or financial relationships that could be construed as a
potential conflict of interest. Keum, N., and Giovannucci, E. (2019). Global Burden of Colorectal Cancer:
Emerging Trends, Risk Factors and Prevention Strategies. Nat. Rev. Gastroenterol. Hepatol. 16, 713–732. doi: 10.1038/s41575-019-0189-8 Liguori, G., Lamas, B., Richard, M. L., Brandi, G., da Costa, G., Hoffmann, T. W.,
et al. (2016). Fungal Dysbiosis in Mucosa-Associated Microbiota of Crohn’s
Disease Patients. J. Crohns Colitis 10, 296–305. doi: 10.1093/ecco-jcc/jjv209 Publisher’s Note: All claims expressed in this article are solely those of the authors
and do not necessarily represent those of their affiliated organizations, or those of
the publisher, the editors and the reviewers. Any product that may be evaluated in
this article, or claim that may be made by its manufacturer, is not guaranteed or
endorsed by the publisher. Luan, C., Xie, L., Yang, X., Miao, H., Lv, N., Zhang, R., et al. (2015). Dysbiosis of
Fungal Microbiota in the Intestinal Mucosa of Patients With Colorectal
Adenomas. Sci. Rep. 5, 7980. doi: 10.1038/srep07980 Peters, U., Bien, S., and Zubair, N. (2015). Genetic Architecture of Colorectal
Cancer. Gut 64, 1623–1636. doi: 10.1136/gutjnl-2013-306705 Copyright © 2022 Gao, Xia, Wu, Zhong, Sun, Zhu, Huang, Wu, Yin, Yang, Chen and
Qin. This is an open-access article distributed under the terms of the Creative
Commons Attribution License (CC BY). The use, distribution or reproduction in other
forums is permitted, provided the original author(s) and the copyright owner(s) are
credited and that the original publication in this journal is cited, in accordance with
accepted academic practice. No use, distribution or reproduction is permitted which
does not comply with these terms. REFERENCES Qin, N., Yang, F., Li, A., Prifti, E., Chen, Y., Shao, L., et al. (2014). Alterations of the
b
h
d Qin, N., Yang, F., Li, A., Prifti, E., Chen, Y., Shao, L., et al. (2014). Alterations of the
Human Gut Microbiome in Liver Cirrhosis. Nature 513, 59–64. doi: 10.1038/
nature13568 Human Gut Microbiome in Liver Cirrhosis. Nature 513, 59–64. doi: 10.1038/
nature13568 Richard, M. L., and Sokol, H. (2019). The Gut Mycobiota: Insights Into Analysis,
Environmental Interactions and Role in Gastrointestinal Diseases. Nat. Rev. Gastroenterol. Hepatol 16 (6), 331–345. doi: 10.1038/s41575-019-0121-2 February 2022 | Volume 12 | Article 839435 Frontiers in Cellular and Infection Microbiology | www.frontiersin.org
|
https://openalex.org/W4280617793
|
https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0268447&type=printable
|
English
| null |
Associations between smoking to relieve stress, motivation to stop and quit attempts across the social spectrum: A population survey in England
|
PloS one
| 2,022
|
cc-by
| 7,981
|
PLOS ONE PLOS ONE RESEARCH ARTICLE Associations between smoking to relieve
stress, motivation to stop and quit attempts
across the social spectrum: A population
survey in England Olga PerskiID*, Maria Theodoraki, Sharon Cox, Loren Kock, Lion ShahabID,
Jamie BrownID Research Department of Behavioural Science and Health, University College London, London, United
Kingdom a1111111111
a1111111111
a1111111111
a1111111111
a1111111111 * olga.perski@ucl.ac.uk Abstract Smoking prevalence in several high-income countries is steadily declining but remains per-
sistently high in ‘lower’ socioeconomic position (SEP) groups, contributing to inequities in
morbidity and mortality. Smoking to relieve stress is a commonly endorsed motive for contin-
ued smoking; however, it remains unclear whether smoking to relieve stress has a negative
impact on motivation to stop and future quit attempts and if so, whether associations are
moderated by SEP. This was an observational study with cross-sectional and prospective
survey data from the nationally representative Smoking Toolkit Study in England. A total of
1,135 adult smokers were surveyed at baseline, with 153 (13.5%) respondents followed up
at 12 months. Respondents provided information on demographic, social and smoking char-
acteristics. A series of multivariable logistic regression analyses was conducted. Bayes Fac-
tors (BFs) were calculated to explore non-significant associations. Smoking to relieve stress
was commonly endorsed by respondents from both ‘lower’ (43.2% [95% CI = 39.4%,
47.0%]) and ‘higher’ (40.5% [95% CI = 35.9%, 45.1%]) SEP groups (p = 0.39). Smoking to
relieve stress was associated with high motivation to stop at baseline (ORadj = 1.48, 95% CI
= 1.03–2.12, p = 0.035) but not significantly with the odds of making a quit attempt at a 12-
month follow-up, although the magnitude and direction of the effect was similar to that
observed for high motivation to stop (ORadj = 1.49, 95% CI = 0.69–3.20, p = 0.3). Data were
insensitive to detect moderation effects of SEP (BF = 0.90 and BF = 1.65, respectively). Smoking to relieve stress is a commonly endorsed motive and is associated with high moti-
vation to stop but not significantly with the odds of making a quit attempt in the next 12
months, although the magnitude and direction of the effect was similar for both outcomes. There was no clear evidence of moderation by SEP, although data were insensitive to distin-
guish the alternative from the null hypothesis. Introduction between_smoking_to_relieve_stress_motivation_
to_stop_and_future_quit_attempts_across_the_
social_spectrum_A_population_survey_in_
England/14731029. between_smoking_to_relieve_stress_motivation_
to_stop_and_future_quit_attempts_across_the_
social_spectrum_A_population_survey_in_
England/14731029. Tobacco smoking remains one of the leading causes of premature illness and death, with global
smoking-related deaths approximating 8 million people per year in 2019 [1]. Smoking preva-
lence in a number of high-income countries, including England, has been steadily declining
for the past decade but remains persistently high in ‘lower’ socioeconomic position (SEP)
groups [2]. In England, ‘lower’ SEP is associated with increased morbidity and mortality, of
which smoking is a significant contributor [3]. To help reduce observed health inequities
between ‘higher’ and ‘lower’ SEP groups [4], supporting people to stop smoking–particularly
those from priority SEP groups–is urgently needed. The development of effective policies and
interventions requires the identification of key barriers to smoking cessation, such as beliefs or
motives that hinder smoking cessation attempts. Funding: Cancer Research UK is the main
contributor (C1417/A22962), but the UK
Department of Health, Pfizer, GlaxoSmithKline and
Johnson and Johnson have also all contributed
funding to the data collection for the Smoking
Toolkit Study. The Society for the Study of
Addiction and the National Institute for Health
Research’s School for Public Health Research have
contributed funding to the data collection for the
Alcohol Toolkit Study. JB, LS, OP, SC and LK are
members of SPECTRUM, a UK Prevention
Research Partnership Consortium (MR/S037519/
1). UKPRP is an initiative funded by the UK
Research and Innovation Councils, the Department
of Health and Social Care (England) and the UK
devolved administrations, and leading health
research charities. The funders had no final role in
the study design; in the collection, analysis and
interpretation of data; in the writing of the report; or
in the decision to submit the paper for publication. All researchers listed as authors are independent
from the funders and all final decisions about the
research were taken by the investigators and were
unrestricted. Motivational factors, including desire or intention to stop, have been identified as key pre-
dictors of smoking cessation attempts [5]. Although longitudinal studies show that smoking
cessation (as compared with continued smoking) is associated with reduced stress, anxiety and
depression–with equal improvements to mental wellbeing observed in adults with and without
a mental health diagnosis [6]–approximately 40% of smokers in England indicate that they
smoke to cope with stress or anxiety [7]. However, it remains unclear whether smoking to
relieve stress undermines motivation to stop and subsequent quit attempts. Introduction According to the
PRIME (Plans, Responses, Impulses, Motives, Evaluations) Theory of Motivation [8], plans to
stop smoking influence behaviour only if they generate sufficiently strong impulses at relevant
moments in time. However, competing motives (including the belief that smoking helps to
relieve stress) may act to undermine both plans and subsequent quit attempts by generating
strong, opposing impulses. It is therefore plausible that the belief that smoking relieves stress
may lead to reduced motivation to stop or it may undermine intentions to stop by generating
strong, competing impulses which contribute to continued smoking. Previous research has
examined whether the belief that one is addicted to smoking (‘perceived addiction’) under-
mines motivation to stop and future quit attempts. However, contrary to predictions, per-
ceived addiction to smoking was recently found to be positively associated with motivation to
stop [9] and future quit attempts [10]. Competing interests: OP, MT, SC and LK have no
conflicts of interest to declare. LS has received a
research grant and honoraria for a talk and travel
expenses from manufacturers of smoking
cessation medications (Pfizer and Johnson &
Johnson). JB has received unrestricted research
funding from Pfizer to study smoking cessation. This does not alter our adherence to PLOS ONE’s
policies on sharing data and materials. SEP refers to social and economic factors that influence the position that individuals inhabit
within the structures of society, and which in turn influence their health [11]. These factors
typically include (but are not limited to) income, educational attainment, home ownership/
tenure, occupation and employment status. The term ‘lower’ SEP is used in this study to reflect
the relatively average lower income and status of those in routine and manual occupational
trades and those who are unemployed. Smokers from lower SEP groups face multiple environ-
mental and social stressors, including financial and occupational hardship and instability, as
well as poor physical and mental health [11]. They also face smoking-specific stressors such as
a lack of social support and higher nicotine dependence (compared with smokers from more
advantaged groups) [12, 13], which means that negative affect from withdrawal is likely experi-
enced as more intense and stressful, also highlighting the role of negative affect control
through continued smoking [14]. OPEN ACCESS Citation: Perski O, Theodoraki M, Cox S, Kock L,
Shahab L, Brown J (2022) Associations between
smoking to relieve stress, motivation to stop and
quit attempts across the social spectrum: A
population survey in England. PLoS ONE 17(5):
e0268447. https://doi.org/10.1371/journal. pone.0268447 Editor: Jesse T. Kaye, University of Wisconsin-
Madison, UNITED STATES
Received: June 4, 2021
Accepted: April 29, 2022
Published: May 17, 2022 Editor: Jesse T. Kaye, University of Wisconsin-
Madison, UNITED STATES
Received: June 4, 2021
Accepted: April 29, 2022
Published: May 17, 2022 Peer Review History: PLOS recognizes the
benefits of transparency in the peer review
process; therefore, we enable the publication of
all of the content of peer review and author
responses alongside final, published articles. The
editorial history of this article is available here:
https://doi.org/10.1371/journal.pone.0268447 Copyright: © 2022 Perski et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which
permits unrestricted use, distribution, and
reproduction in any medium, provided the original
author and source are credited. Data Availability Statement: The dataset
underpinning the analyses is available via Figshare:
https://figshare.com/articles/dataset/Associations_ Data Availability Statement: The dataset 1 / 13 PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 PLOS ONE Smoking to relieve stress, motivation to stop and quit attempts PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 Introduction Several qualitative studies have highlighted the role of smoking to cope with stress in partic-
ular subgroups of smokers, including adults experiencing homelessness [15], smokers living
with psychiatric conditions [16], heavy smokers [17] and older smokers [18]. However, it
remains unclear whether smoking to relieve stress is more commonly endorsed in smokers
from lower (compared with higher) SEP groups, but it is plausible given the frequent occur-
rence of high stress levels in lower SEP groups, coupled with the widely held belief that smok-
ing relieves stress. In addition, the belief that smoking is beneficial for stress is likely weighed 2 / 13 PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 PLOS ONE Smoking to relieve stress, motivation to stop and quit attempts against perceived benefits of quitting, such as improved health and financial savings (which
could help alleviate financial hardship) [19]. It is therefore important to examine not only
whether smoking to relieve stress has a negative impact on motivation to stop and subsequent
attempts to quit, but also whether these associations are moderated by SEP. Recent research
indicates that although motivation to stop appears similar by housing tenure–a reliable indica-
tor of SEP and predictor of smoking status [20]–and prevalence of past-year quit attempts are
higher in adults living in homes that belong to a housing association or are rented from local
authority (compared with other housing), people from lower SEP groups are less likely to suc-
ceed in quitting [21]. We therefore aimed to examine, in the nationally representative Smoking Toolkit Study,
the associations of smoking to relieve stress with motivation to stop (measured at baseline)
and quit attempts at a 12-month follow-up in England, and whether these associations are
moderated by SEP. Specifically, we aimed to address the following research questions: 1. Do smokers who indicate that they smoke to relieve stress have reduced odds of high (vs. low) motivation to stop smoking, without and with adjustment for age, sex, SEP, children
in the household, cigarettes smoked per day and number of quit attempts in the past year? 2. Do smokers who indicate that they smoke to relieve stress have reduced odds of making a
quit attempt at a 12-month follow-up, without and with adjustment for age, sex, SEP, chil-
dren in the household, cigarettes smoked per day and number of quit attempts in the past
year? 3. Introduction Does SEP moderate any associations between smoking to relieve stress and a) high motiva-
tion to stop and b) quit attempts at a 12-month follow-up, without and with adjustment for
age, sex, SEP, children in the household, cigarettes per day and number of quit attempts in
the past year? PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 Measures Outcome variables. The first outcome variable was motivation to stop, measured at base-
line with the validated Motivation To Stop Scale [25, 26]. Respondents are asked: “Which of
the following best describes you?” Response options include: 1) I don’t want to stop smoking;
2) I think I should stop smoking but don’t really want to; 3) I want to stop smoking but haven’t
thought about when; 4) I REALLY want to stop smoking, but I don’t know when I will; 5) I
want to stop smoking and hope to soon; 6) I REALLY want to stop smoking and intend to in
the next 3 months; 7) I REALLY want to stop smoking and intend to in the next month. To aid
interpretation, responses were dichotomised into low (response options 1–5) and high
(response options 6–7) motivation to stop, as previously done in studies using this variable
[27, 28]. The second outcome variable was quit attempts at a 12-month follow-up, measured with a
single item: “How many serious attempts to stop smoking have you made in the last 12
months? By serious attempt I mean you decided that you would try to make sure you never
smoked again.” Responses were coded 0 for respondents who reported no quit attempt and 1
for those who reported 1+ quit attempts. Explanatory variable. The explanatory variable was smoking to relieve stress, measured
at baseline with a single item asking respondents to select from a list the motives that they
believe are important in keeping them smoking. Those endorsing the response option “It helps
me cope with stress or anxiety” were coded as 1, the rest as 0. Covariates. Covariates measured at baseline included: age (16–24 years, 25–34 years, 35–
44 years, 45–54 years, 55–64 years, 65+ years); sex (male, female); SEP, operationalised as
occupational social grade and measured with the British National Readership Survey’s Social
Grade Classification Tool [29], which comprises the categories AB (higher and intermediate
managerial, administrative and professional), C1 (supervisory, clerical and junior managerial,
administrative and professional), C2 (skilled manual workers), D (semi-skilled and unskilled
manual workers) and E (state pensioners, casual and lowest-grade workers, unemployed with
state benefits), with responses grouped into ‘lower’ (C2DE) and ‘higher’ (ABC1) social grade;
children in the household (no vs. Ethics statement Ethical approval was granted by UCL’s Research Ethics Committee (0498/001). Respondents
provided verbal informed consent prior to each interview. Study design and setting This was an observational study involving cross-sectional and prospective survey data. The
STROBE guidelines were used in the design and reporting of this study [22]. The study is part of the ongoing Smoking Toolkit Study (STS), which involves monthly,
face-to-face, computer-assisted household surveys of adults aged 16+ in England [23, 24]. The
sample is a hybrid of a random probability and quota sample, which results in a sample that is
representative of the adult population of smokers in England. Interviews are held with one
household member in selected geographic output areas until quotas are fulfilled. The quotas
are based on factors influencing the probability of being at home (i.e. working status, age and
gender). This hybrid form of random probability and quota sampling is considered superior to
conventional quota sampling. Here, the choice of households to approach is limited by the ran-
dom allocation of small output areas and rather than being sent to specific households in
advance, interviewers can choose which households within these small geographic areas are
most likely to fulfil their quotas. Therefore, unlike random probability sampling, it is not
appropriate to record the response rate in the STS. Data included in the present study were col-
lected across four waves (139–142) from respondents surveyed between April and July 2018
(when smoking to relieve stress was included in the STS). Attempts to recontact consenting
past-year smokers via telephone are made 12 months later. Follow-up respondents are not
remunerated. Up to eight attempts are made to follow up each consenting respondent, with
calls made at different times of day across weekdays and weekends. 3 / 13 PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 PLOS ONE Smoking to relieve stress, motivation to stop and quit attempts Initial analyses were conducted as part of a student project. An extended study protocol
and analysis plan were pre-registered on the Open Science Framework prior to conducting the
analyses (https://osf.io/efbn2). Inclusion criteria Respondents were included in the analyses if they were aged 16+ years and smoked cigarettes
at the time of the baseline survey. Respondents who indicated that they did not smoke ciga-
rettes but did smoke tobacco of some kind were not included (~0.4%) as they do not complete
equivalent measures of dependence (e.g. cigarettes per day). Respondents with missing data on
any of the variables of interest were excluded from the analyses. PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 Measures yes); cigarettes per day (converted to daily consumption for
non-daily smokers who reported the number of cigarettes smoked per week); and number of
quit attempts in the past year (0, 1, 2, 3, 4+). We also captured housing tenure as an alternative indicator of SEP [20]. Respondents
whose homes belonged to a housing association or were rented from local authority were PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 4 / 13 PLOS ONE Smoking to relieve stress, motivation to stop and quit attempts categorised as ‘lower’ SEP. All other responses (i.e. houses which were ‘bought on a mortgage’,
‘owned outright by household’, ‘rented from private landlord’, ‘other’) were categorised as
‘higher’ SEP. Data analysis Analyses were conducted in RStudio v.1.2.5033. Data were weighted with the rim (mar-
ginal) technique [30] to match the analytic sample to the proportions of the English population
profile on the dimensions of age, social grade, region, housing tenure, ethnicity and working
status within sex. We report descriptive statistics for the baseline and follow-up samples. Any
differences between the baseline and follow-up samples were assessed with Chi-square or t-
tests, as appropriate. To address RQ1 and RQ2, unweighted logistic regression analyses were conducted, without
and with adjustment for all covariates. To address RQ3, the analyses were repeated, including
the two-way interaction between smoking to relieve stress and SEP. As a planned sensitivity
analysis, the analyses were repeated with housing tenure used as the indicator of SEP [20]. Bayes Factors. In the event of non-significant interactions, we had planned to calculate
Bayes Factors (using an online calculator; www.bayesfactor.info) to examine whether the non-
significant associations could best be characterised as evidence of no association, evidence of
an association, or whether the data were insensitive to detect an association. As there was lim-
ited evidence to inform what effect sizes to expect for the potential interactions with SEP, we
set the expected effect sizes to OR = 0.7, informed by previous research examining the associa-
tion between enjoyment of smoking and future quit attempts [31]. The alternative hypothesis
was conservatively represented by a half-normal distribution. Bayes Factors (BFs) can be inter-
preted as follows: BFs >3 lend support to the alternative hypothesis (over the null), BFs <1/3
lend support to the null, and BFs in-between reflect data being insensitive to distinguish the
two. PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 PLOS ONE PLOS ONE Table 1. Demographic, social and smoking characteristics of current cigarette smokers at baseline and at the 12-month follow-up. Baseline sample
Follow-up sample
Unweighted (N = 1,135)
Weighted (N = 1,170)
Unweighted (N = 153)
Weighted (N = 152)
p-value
Sex, N (%)
0.78
Women
557 (49%)
550 (47%)
73 (48%)
69 (45%)
Men
578 (51%)
620 (53%)
80 (52%)
84 (55%)
Age, N (%)
<0.001
16–24 years
189 (17%)
194 (17%)
13 (8.5%)
13 (8.2%)
25–34 years
242 (21%)
287 (25%)
20 (13%)
24 (16%)
35–44 years
191 (17%)
224 (19%)
27 (18%)
34 (22%)
45–54 years
204 (18%)
206 (18%)
30 (20%)
29 (19%)
55–64 years
152 (13%)
133 (11%)
27 (18%)
24 (15%)
65+ years
157 (14%)
125 (11%)
36 (24%)
29 (19%)
SEP, N (%)
<0.001
Higher
457 (40%)
455 (39%)
84 (55%)
82 (54%)
Lower
678 (60%)
715 (61%)
69 (45%)
71 (46%)
Housing tenure, N (%)
0.44
Higher
767 (68%)
905 (77%)
108 (71%)
121 (79%)
Lower
368 (32%)
264 (23%)
45 (29%)
31 (21%)
Children in the household, N (%)
0.02
No
760 (67%)
774 (66%)
116 (76%)
114 (75%)
Yes
375 (33%)
396 (34%)
37 (24%)
38 (25%)
Cigarettes per day, M (SD)
10.6 (8.0)
10.3 (7.8)
11.4 (8.1)
10.8 (7.7)
0.25
Number of quit attempts in the past year, N (%)
0.17
0
827 (73%)
859 (73%)
119 (78%)
119 (78%)
1
182 (16%)
184 (16%)
23 (15%)
21 (14%)
2
68 (6.0%)
74 (6.3%)
9 (5.9%)
10 (6.6%)
3
33 (2.9%)
31 (2.6%)
0 (0%)
0 (0%)
4+
25 (2.2%)
22 (1.9%)
2 (1.3%)
2 (1.1%)
Smoking to relieve stress, N (%)
0.58
No
657 (58%)
686 (59%)
85 (56%)
87 (57%)
Yes
478 (42%)
484 (41%)
68 (44%)
65 (43%)
Motivation to stop smoking, N (%)
0.32
Low
968 (85%)
1,004 (86%)
135 (88%)
136 (89%)
High
167 (15%)
166 (14%)
18 (12%)
17 (11%)
Quit attempt at the 12-month follow-up, N (%)
No
-
-
89 (58%)
88 (58%)
-
Yes
-
-
64 (42%)
64 (42%)
SEP = socioeconomic position
p-values pertain to comparisons of the baseline and follow-up samples (unweighted), with values <0.05 highlighted in bold the planned sensitivity analyses with housing tenure (ORadj = 0.34, 95% CI = 0.03–4.31, p = 0.4
and ORadj = 0.72, 95% CI = 0.14–3.8, p = 0.7, respectively). Results A total of 1,203 cigarette smokers were surveyed between April and July 2018, of whom 1,135
(94.3%; unweighted) had complete data on all variables of interest. A total of 153 (13.5%;
unweighted) respondents provided data at the 12-month follow-up (see Table 1). Compared
with the baseline sample, those responding to the 12-month follow-up survey were older
(p < 0.001), more likely to be from higher SEP groups (p < 0.001) and less likely to have chil-
dren in the household (p = 0.02). At baseline, a total of 43.2% (95% CI = 39.4%, 47.0%) of
respondents from lower SEP groups indicated that they smoke to relieve stress, compared with
40.5% (95% CI = 35.9%, 45.1%) of respondents from higher SEP groups (p = 0.39). In unadjusted and adjusted analyses without the interaction, smoking to relieve stress was
associated with 48% greater odds of high motivation to stop (ORadj = 1.48, 95% CI = 1.03–
2.12, p = 0.035; see Table 2). The association between smoking to relieve stress and quit
attempts at the 12-month follow-up was not significant (ORadj = 1.49, 95% CI = 0.69–3.20,
p = 0.3). The adjusted associations between the exposure and outcome variables were
unchanged in the sensitivity analyses with housing tenure (see S1 Table). In an unplanned sen-
sitivity analysis with cigarettes per day coded as a categorical variable, the associations were
similar (see S2 Table). In unadjusted and adjusted analyses, the two-way interactive effects of smoking to relieve
stress and SEP on high motivation to stop (ORadj = 1.66, 95% CI = 0.14–24.3, p = 0.7) and quit
attempts at the 12-month follow-up (ORadj = 0.31, 95% CI = 0.1–1.4, p = 0.12) were not signifi-
cant (see S3 and S4 Tables for the ORs stratified by SEP). Results remained non-significant in 5 / 13 PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 Smoking to relieve stress, motivation to stop and quit attempts PLOS ONE Table 2. Unadjusted and adjusted odds ratios for the associations of smoking to relieve stress with i) high motivation to stop and ii) quit attempts at the 12-month
follow-up. Bayes Factors (BFs) The calculation of BFs indicated that the data on the two-way interactive effects of smoking to
relieve stress and SEP on high motivation to stop and quit attempts at the 12-month follow-up
were insensitive to detect an association (BF = 0.90 and BF = 1.65, respectively). As an 6 / 13 PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 Smoking to relieve stress, motivation to stop and quit attempts ^ = Odds Ratio
ORadj = adjusted for sex, age, SEP, children in the household, CPD and number of quit attempts in the past year
- could not be estimated due to low cell counts e household, CPD and number of quit attempts in the past year PLOS ONE High motivation to stop (N = 1,135)
Quit attempts at the 12-month follow-up
(N = 153)
OR^
95% CI
p-value
OR
95% CI
p-value
Smoking to relieve stress (ref = No)
Yes
1.75
1.26, 2.43
<0.001
1.64
0.86, 3.16
0.13
Sex (ref = Women)
Men
0.80
0.57, 1.11
0.2
0.31
0.09, 0.87
0.033
Age (ref = 16–24 years)
25–34 years
1.16
0.71, 1.94
0.6
3.00
0.38, 62.8
0.4
35–44 years
1.06
0.62, 1.83
0.8
2.09
0.27, 43.3
0.5
45–54 years
0.84
0.49, 1.47
0.5
1.33
0.15, 28.5
0.8
55–64 years
0.64
0.33, 1.20
0.2
1.50
0.17, 32.1
0.7
65+ years
0.42
0.20, 0.83
0.016
1.09
0.13, 23.2
>0.9
SEP (ref = Higher)
Lower
0.69
0.50, 0.97
0.030
0.57
0.19, 1.56
0.3
Children in the household (ref = No)
Yes
1.39
0.99, 1.95
0.055
0.16
0.01, 0.83
0.082
CPD
0.96
0.93, 0.98
<0.001
0.93
0.86, 1.00
0.074
Number of quit attempts in the past year (ref = 0)
1
5.72
3.83, 8.55
<0.001
5.35
1.70, 16.5
0.003
2
6.50
3.68, 11.3
<0.001
3.49
0.47, 17.3
0.2
3
5.96
2.68, 12.6
<0.001
-
-
-
4+
6.71
2.74, 15.5
<0.001
-
-
-
High motivation to stop (N = 1,135)
Future quit attempt (N = 153)
ORadj
95% CI
p-value
ORadj
95% CI
p-value
Smoking to relieve stress (ref = No)
Yes
1.48
1.03, 2.12
0.035
1.49
0.69, 3.20
0.3
Sex (ref = Women)
Men
0.96
0.67, 1.38
0.8
1.32
0.62, 2.85
0.5
Age (ref = 16–24 years)
25–34 years
1.04
0.60, 1.82
0.9
0.61
0.12, 2.97
0.5
35–44 years
0.97
0.53, 1.77
>0.9
0.40
0.08, 1.80
0.2
45–54 years
1.01
0.55, 1.83
>0.9
0.50
0.11, 2.19
0.4
55–64 years
0.96
0.47, 1.89
0.9
0.21
0.04, 0.98
0.051
65+ years
0.54
0.25, 1.14
0.11
0.33
0.07, 1.42
0.14
SEP (ref = Higher)
Lower
0.72
0.50, 1.04
0.084
1.30
0.63, 2.70
0.5
Children in the household (ref = No)
Yes
1.18
0.78, 1.78
0.4
0.93
0.37, 2.30
0.9
CPD
0.96
0.94, 0.99
0.007
1.00
0.96, 1.05
0.8
Number of quit attempts in the past year (ref = 0)
1
5.29
3.50, 8.00
<0.001
6.09
2.20, 19.0
<0.001
2
6.08
3.40, 10.7
<0.001
5.63
1.20, 40.6
0.044
3
5.41
2.37, 11.8
<0.001
-
-
-
4+
7.13
2.83, 17.1
<0.001
3.23
0.11, 90.9
0.4
SEP = socioeconomic position Table 2. ^ = Odds Ratio
ORadj = adjusted for sex, age, SEP, children in the household, CPD and number of quit attempts in the past year
- could not be estimated due to low cell counts Principal findings This study aimed to examine whether smoking to relieve stress is associated with high motiva-
tion to stop at baseline and quit attempts at a 12-month follow-up, and whether any associa-
tions are moderated by SEP. Contrary to expectations, we found that smoking to relieve stress
was associated with high motivation to stop smoking, but not significantly with the odds of
making a quit attempt at the 12-month follow-up. Although non-significant, the direction and
magnitude of the association of smoking to relieve stress with future quit attempts were similar
to those observed for the association with high motivation to stop. We did not observe signifi-
cant moderation by SEP; however, the Bayes Factors indicated that data were insensitive to
detect an association (as opposed to lending support to the null hypothesis of no association). For this to be known, other studies with larger samples need to be conducted to detect any
potential moderation effects by SEP. The finding that smoking to relieve stress is associated with high (as opposed to low) moti-
vation to stop is consistent with previous research indicating that the belief that one is addicted
to smoking is positively associated with motivation to stop [9]. There are several plausible
explanations for this finding. First, people who smoke to relieve stress may evaluate their
smoking experience as biological or instrumental (as opposed to pleasurable), which may be
perceived as unpleasant or annoying, hence leading to greater motivation to stop. Second,
those who smoke to relieve stress may find smoking enjoyable but at the same time, find it a
source of dissonance to use smoking as a ‘crutch’ to cope with stress, hence leading to greater
motivation to stop. Third, it is also possible that there is a common factor (e.g., depression)
that gives rise both to the belief that smoking helps to relieve stress and high motivation to
stop. Previous research has found that smokers with more severe (compared with less severe)
levels of depression report lower quitting self-efficacy (which may be influenced by positive
outcome expectations, such as the belief that smoking helps to cope with stress) but higher
motivation to stop [32]. PLOS ONE Unadjusted and adjusted odds ratios for the associations of smoking to relieve stress with i) high motivation to stop and ii) quit attempts at the 12-month
ollow-up. os for the associations of smoking to relieve stress with i) high motivation to stop and ii) quit attempts at the 12-month Smoking to relieve stress (ref = No) 7 / 13 PLOS ONE Smoking to relieve stress, motivation to stop and quit attempts unplanned sensitivity analysis, we also calculated a BF for the non-significant association
between smoking to relieve stress and quit attempts at the 12-month follow-up using the same
prior as the above analyses, which indicated that data were insensitive to detect an association
(BF = 0.46). Principal findings Fourth, as both smoking to relieve stress and motivation to stop were
measured at the same time, there is potential for reverse causation, whereby those highly moti-
vated to stop are also more likely to identify motives for smoking that some people may judge
negatively (e.g. they may judge it unpleasant to feel that smoking is needed to relieve stress). The finding that smokers from both higher and lower SEP groups endorse the belief that
smoking helps to relieve stress may indicate that smokers are not only more/less likely to
endorse this belief depending on their level of actual stressors (which may, on average, be
higher in smokers from lower SEP groups). Instead, this may be related to people’s perceived
ability to cope with stressors. Smokers across the social spectrum may perceive themselves to
be better/worse equipped to cope with stress (irrespective of whether they actually are), thus
influencing their beliefs about the role of smoking (e.g. positive outcome expectancies). Strengths and limitations This study was strengthened by examining associations in a nationally representative sample
of smokers in England. To our knowledge, this was the first study to examine the associations
of smoking to relieve stress, motivation to stop and future quit attempts in addition to differ-
ences in smoking to relieve stress by SEP. However, our study also had several limitations. 8 / 13 PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 PLOS ONE Smoking to relieve stress, motivation to stop and quit attempts First, the sample size for the prospective association of smoking to relieve stress and future
quit attempts was small, which led to imprecision. However, this was pre-determined by the
period for which the funding was available (i.e., the question about smoking motives–includ-
ing smoking to relieve stress–was included only in a few STS waves), and we attempted to miti-
gate this by calculating Bayes Factors to elucidate whether the data provided evidence of no
association or whether they were insensitive to detect an association. Second, the follow-up
sample differed from the baseline sample on important characteristics, including SEP. This
means that, had our findings pertaining to the follow-up sample been statistically significant,
they may not be generalisable to the general population of smokers. In addition, if those who
were more likely to be followed up (i.e. older smokers, men, those from higher SEP groups)
were also more or less likely to endorse the belief that they smoke to relieve stress, this may
have distorted any association with the outcome. Third, although the Smoking Toolkit Study
is a nationally representative survey on key sociodemographic and smoking characteristics, it
may not be representative with regards to psychological characteristics such as motivation to
stop or the motive that smoking helps to relieve stress and it also may not reach smokers who
are the most disadvantaged. Similar to the previous point about the follow-up sample, this may
mean our findings are not generalisable to the general population of smokers. Fourth, the sur-
vey during this study did not collect data on perceived stress levels; this would be a useful vari-
able to consider in future research. Fifth, smokers may not have recalled (and reported) all quit
attempts made in the 12 months preceding the follow-up survey [33, 34]. Sixth, the analyses
pertaining to motivation to stop were cross-sectional and therefore the direction of the associa-
tion is unclear. PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 Implications for research, policy and practice Future research to unpick the potential explanations for the positive association between
smoking to relieve stress and high motivation to stop would benefit from deploying qualitative
methods and/or Ecological Momentary Assessments in smokers’ daily lives, allowing a closer
examination of the temporal dynamics of competing (or synergistic) motives, evaluations and
impulses [8, 35]. Further understanding of the relationship between smoking to relieve stress
and future quit attempts is also required in studies with larger sample sizes. As many quit
attempts are, on average, needed before quitting smoking successfully [36], a positive relation-
ship between smoking to relieve stress and making a quit attempt in the future would likely
have a positive impact on public health. The finding that smoking to relieve stress is a commonly endorsed motive in smokers from
both lower and higher SEP groups indicates that public health interventions may benefit from
tackling such misperceptions about smoking and stress relief, with evidence from a recent sys-
tematic review and meta-analysis of longitudinal studies indicating that smoking cessation
(compared with continued smoking) is associated with reduced stress, anxiety and depression
[6]. Although the finding that smoking to relieve stress is associated with high motivation to
stop (and possibly the likelihood of making a quit attempt in the future) may be perceived as a
positive finding that does not warrant intervention, it may be more ethically defensible to
highlight to smokers the large body of work indicating that smoking cessation leads to positive
mental health outcomes and use this as a motive for stopping, thus correcting common mis-
perceptions. In addition, if smoking is normatively perceived as a stress reducer, then it may
encourage people to take up smoking. This merits further investigation. At the same time (although not measured in the present study), research shows that many
mental health professionals believe that smoking helps to alleviate stress and therefore refrain
from offering appropriate smoking cessation support to their clients [37]. This suggests that PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 9 / 13 PLOS ONE Smoking to relieve stress, motivation to stop and quit attempts the tackling of common misperceptions also needs to occur among practitioners. Public health
campaigns have often focused on the well-documented physical health aspects of smoking,
with less attention paid to the mental health benefits of quitting, including reduced stress, anxi-
ety and depression [6] but also increased levels of happiness [38, 39]. Conclusion Smoking to relieve stress is a commonly endorsed motive and is associated with high motiva-
tion to stop but not significantly with the odds of making a future quit attempt, although the
magnitude and direction of the effect was similar for both outcomes. There was no clear evi-
dence of moderation by SEP, although data were insensitive to distinguish the alternative from
the null hypothesis. Implications for research, policy and practice With increasing evidence
for how to best counter misperceptions without inadvertently reinforcing them in the areas of
vaccine hesitancy and climate change (e.g. normative feedback, framing messages in terms of
gain) [40–42], interventions targeting healthcare professionals may benefit from drawing on
this growing literature. Finally, prior research shows that although smokers from lower SEP groups try to quit at a
similar rate to smokers from higher SEP groups, they are less likely to succeed [43]. It is plausi-
ble that people from lower SEP groups endorse a confluence of motivational, cognitive and
social factors for continued smoking (e.g. smoking to relieve stress and boredom, lower quit-
ting self-efficacy, social aspects of smoking), which may interact to make it more difficult to
quit [44]. Future research should examine the potential clustering of such factors and whether
certain patterns are more pronounced in lower (compared with higher) SEP groups, as this is
needed to help reduce smoking-related health inequalities. Supporting information S1 Table. Unadjusted and adjusted odds ratios for the associations of smoking to relieve
stress with i) high motivation to stop and ii) quit attempts in the next 12 months in the
planned sensitivity analysis with housing tenure. (DOCX) stress with i) high motivation to stop and ii) quit attempts in the next 12 months in the
planned sensitivity analysis with housing tenure. (DOCX)
S2 Table. Unadjusted and adjusted odds ratios for the associations of smoking to relieve
stress with i) high motivation to stop and ii) quit attempts in the next 12 months in the
unplanned sensitivity analysis with cigarettes per day coded as a categorical variable. (DOCX)
S3 Table. Unadjusted and adjusted odds ratios for the associations of smoking to relieve
stress with i) high motivation to stop and ii) quit attempts in the next 12 months in the
higher SEP group. (DOCX)
S4 Table. Unadjusted and adjusted odds ratios for the associations of smoking to relieve
stress with i) high motivation to stop and ii) quit attempts in the next 12 months in the
lower SEP group. (DOCX)
Acknowledgments
We gratefully acknowledge the funding listed. S2 Table. Unadjusted and adjusted odds ratios for the associations of smoking to relieve
stress with i) high motivation to stop and ii) quit attempts in the next 12 months in the
unplanned sensitivity analysis with cigarettes per day coded as a categorical variable. (DOCX) (DOCX)
S3 Table. Unadjusted and adjusted odds ratios for the associations of smoking to relieve
stress with i) high motivation to stop and ii) quit attempts in the next 12 months in the
higher SEP group. (DOCX)
S4 Table. Unadjusted and adjusted odds ratios for the associations of smoking to relieve
stress with i) high motivation to stop and ii) quit attempts in the next 12 months in the
lower SEP group. (DOCX) S3 Table. Unadjusted and adjusted odds ratios for the associations of smoking to relieve
stress with i) high motivation to stop and ii) quit attempts in the next 12 months in the
higher SEP group. (DOCX) S4 Table. Unadjusted and adjusted odds ratios for the associations of smoking to relieve
stress with i) high motivation to stop and ii) quit attempts in the next 12 months in the
lower SEP group. (DOCX) Acknowledgments We gratefully acknowledge the funding listed. 10 / 13 PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 PLOS ONE Smoking to relieve stress, motivation to stop and quit attempts Author Contributions Conceptualization: Olga Perski, Maria Theodoraki, Sharon Cox, Loren Kock, Lion Shahab,
Jamie Brown. Conceptualization: Olga Perski, Maria Theodoraki, Sharon Cox, Loren Kock, Lion Shahab,
Jamie Brown. Data curation: Olga Perski. Formal analysis: Olga Perski. Formal analysis: Olga Perski. Funding acquisition: Lion Shahab, Jamie Brown. Investigation: Olga Perski. Investigation: Olga Perski. Methodology: Olga Perski. Project administration: Olga Perski. Project administration: Olga Perski. Writing – original draft: Olga Perski. Writing – original draft: Olga Perski. Writing – review & editing: Olga Perski, Maria Theodoraki, Sharon Cox, Loren Kock, Lion
Shahab, Jamie Brown. References Socioeconomic variations in nicotine dependence, self-
efficacy, and intention to quit across four countries: findings from the International Tobacco Control PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 11 / 13 PLOS ONE Smoking to relieve stress, motivation to stop and quit attempts (ITC) Four Country Survey. Tob Control. 2006; 15: iii71–iii75. https://doi.org/10.1136/tc.2004.008763
PMID: 16754950 (ITC) Four Country Survey. Tob Control. 2006; 15: iii71–iii75. https://doi.org/10.1136/tc.2004.008763
PMID: 16754950 14. Parrott AC. Stress modulation over the day in cigarette smokers. Addiction. 1995; 90: 233–244. https://
doi.org/10.1046/j.1360-0443.1995.9022339.x PMID: 7703817 15. Soar K, Dawkins L, Robson D, Cox S. Smoking amongst adults experiencing homelessness: a system-
atic review of prevalence rates, interventions and the barriers and facilitators to quitting and staying quit. J Smok Cessat. 2020; 15: 94–108. https://doi.org/10.1017/jsc.2020.11 16. Lawn SJ, Pols RG, Barber JG. Smoking and quitting: a qualitative study with community-living psychiat-
ric clients. Soc Sci Med. 2002; 54: 93–104. https://doi.org/10.1016/s0277-9536(01)00008-9 PMID:
11820684 17. Thompson B, Thompson LA, Thompson J, Fredickson C, Bishop S. Heavy smokers: a qualitative analy-
sis of attitudes and beliefs concerning cessation and continued smoking. Nicotine Tob Res Off J Soc
Res Nicotine Tob. 2003; 5: 923–933. https://doi.org/10.1080/14622200310001615277 PMID:
14668076 18. Kerr S, Watson H, Tolson D, Lough M, Brown M. Smoking after the age of 65 years: a qualitative explo-
ration of older current and former smokers’ views on smoking, stopping smoking, and smoking cessa-
tion resources and services. Health Soc Care Community. 2006; 14: 572–582. https://doi.org/10.1111/j. 1365-2524.2006.00659.x PMID: 17059499 19. Puljević C, Snoswell A, Rivas L, Ali MM, Greef W de, Ferris J, et al. ‘Money up in smoke’: The financial
benefits of smoking cessation may be more motivating to people who are homeless than potential
health gains. Drug Alcohol Rev. 2021;n/a. https://doi.org/10.1111/dar.13293 PMID: 33829571 20. Beard E, Brown J, Jackson SE, West R, Kock L, Boniface S, et al. Independent Associations Between
Different Measures of Socioeconomic Position and Smoking Status: A Cross-Sectional Study of Adults
in England. Nicotine Tob Res. 2021; 23: 107–114. https://doi.org/10.1093/ntr/ntaa030 PMID: 32026943 21. Jackson SE, Smith C, Cheeseman H, West R, Brown J. Finding smoking hot-spots: a cross-sectional
survey of smoking patterns by housing tenure in England. Addiction. 2019; 114: 889–895. https://doi. org/10.1111/add.14544 PMID: 30597650 22. Elm E Von Altman DG, Egger M Pocock SJ, Gøtzsche C Vandenbroucke JP. The Strengthening the
Reporting of Observational Studies in Epidemiology (STROBE) Statement: guidelines for reporting
observational studies. Lancet. 2007; 370: 1453–1457. References 1. World Health Organisation. WHO Report on the Global Tobacco Epidemic. 2019. Available: https://
www.who.int/tobacco/global_report/en// 2. Office for National Statistics. Adult smoking habits in the UK: 2019. 2019 p. 15. Available: https://www. ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/healthandlifeexpectancies/bulletins/
adultsmokinghabitsingreatbritain/2019#:~:text=In%20the%20UK%2C%20in%202019,Annual%
20Population%20Survey%20(APS).&text=In%20the%20UK%2C%2015.9%25%20of,compared%
20with%2012.5%25%20of%20women. https://doi.org/10.1111/add.14571 PMID: 30701622 3. Lewer D, Jayatunga W, Aldridge RW, Edge C, Marmot M, Story A, et al. Premature mortality attributable
to socioeconomic inequality in England between 2003 and 2018: an observational study. Lancet Public
Health. 2020; 5: e33–e41. https://doi.org/10.1016/S2468-2667(19)30219-1 PMID: 31813773 4. Braveman P, Gruskin S. Defining equity in health. J Epidemiol Community Health. 2003; 57: 254–258. https://doi.org/10.1136/jech.57.4.254 PMID: 12646539 5. Vangeli E, Stapleton J, Smit ES, Borland R, West R. Predictors of attempts to stop smoking and their
success in adult general population samples: a systematic review. Addiction. 2011; 106: 2110–2121. https://doi.org/10.1111/j.1360-0443.2011.03565.x PMID: 21752135 6. Taylor GM, Lindson N, Farley A, Leinberger-Jabari A, Sawyer K, Naude´ R te W, et al. Smoking cessa-
tion for improving mental health. Cochrane Database Syst Rev. 2021 [cited 21 Apr 2021]. https://doi. org/10.1002/14651858.CD013522.pub2 PMID: 33687070 7. Jackson SE, Brown J, Aveyard P, Dobbie F, Uny I, West R, et al. Vaping for weight control: A cross-sec-
tional population study in England. Addict Behav. 2019; 95: 211–219. https://doi.org/10.1016/j.addbeh. 2019.04.007 PMID: 30981033 8. West R, Brown J. Theory of Addiction. 2nd ed. Wiley-Blackwell; 2013. 9. Perski O, Herd N, West R, Brown J. Perceived addiction to smoking and associations with motivation to
stop, quit attempts and quitting success: A prospective study of English smokers. Addict Behav. 2019;
90: 306–311. https://doi.org/10.1016/j.addbeh.2018.11.030 PMID: 30476896 10. Chaiton M, Cohen JE, Bondy SJ, Selby P, Brown KS, Ferrence R, et al. Perceived Addiction as a Pre-
dictor of Smoking Cessation Among Occasional Smokers. J Smok Cessat. 2017; 12: 165–172. https://
doi.org/10.1017/jsc.2015.19 11. Galobardes B, Shaw M, Lawlor DA, Lynch JW, Davey Smith G. Indicators of socioeconomic position
(part 1). J Epidemiol Community Health. 2006; 60: 7–12. https://doi.org/10.1136/jech.2004.023531
PMID: 16361448 12. Hiscock R, Bauld L, Amos A, Fidler JA, Munafò M. Socioeconomic status and smoking: a review: His-
cock et al. Ann N Y Acad Sci. 2012; 1248: 107–123. https://doi.org/10.1111/j.1749-6632.2011.06202.x
PMID: 22092035 13. Siahpush M, McNeill A, Borland R, Fong GT. References https://doi.org/10.1016/S0140-6736(07)61602-X
PMID: 18064739 23. Fidler JA, Shahab L, West O, Jarvis MJ, McEwen A, Stapleton JA, et al. “The smoking toolkit study”: a
national study of smoking and smoking cessation in England. BMC Public Health. 2011; 11: 479. https://doi.org/10.1186/1471-2458-11-479 PMID: 21682915 24. Beard E, Brown J, West R, Acton C, Brennan A, Drummond C, et al. Protocol for a national monthly sur-
vey of alcohol use in England with 6-month follow-up: ‘The Alcohol Toolkit Study.’ BMC Public Health. 2015;15. https://doi.org/10.1186/s12889-015-1378-1 PMID: 25605404 25. Hummel K, Brown J, Willemsen MC, West R, Kotz D. External validation of the motivation to stop scale
(MTSS): Findings from the international tobacco control (ITC) Netherlands survey. Eur J Public Health. 2016; 27: 129–134. https://doi.org/10.1093/eurpub/ckw105 PMID: 28177479 26. Kotz D, Brown J, West R. Predictive validity of the Motivation To Stop Scale (MTSS): A single-item mea-
sure of motivation to stop smoking. Drug Alcohol Depend. 2013; 128: 15–19. https://doi.org/10.1016/j. drugalcdep.2012.07.012 PMID: 22943961 27. Jackson SE, Beard E, Michie S, Shahab L, Raupach T, West R, et al. Are smokers who are regularly
exposed to e-cigarette use by others more or less motivated to stop or to make a quit attempt? A cross-
sectional and longitudinal survey. BMC Med. 2018; 16: 1–9. https://doi.org/10.1186/s12916-018-1195-
3 PMID: 30424771 28. Perski O, Jackson SE, Garnett C, West R, Brown J. Trends in and factors associated with the adoption
of digital aids for smoking cessation and alcohol reduction: A population survey in England. Drug Alco-
hol Depend. 2019; 205: 1–7. https://doi.org/10.1016/j.drugalcdep.2019.107653 PMID: 31675544 29. National Readership Survey. Social Grade. Available: http://www.nrs.co.uk/nrs-print/lifestyle-and-
classification-data/social-grade/ 30. Sharot T. Weighting survey results. J Mark Res Soc. 1986; 28: 269–284. 31. Fidler JA, West R. Enjoyment of smoking and urges to smoke as predictors of attempts and success of
attempts to stop smoking: A longitudinal study. Drug Alcohol Depend. 2011; 115: 30–34. https://doi.org/
10.1016/j.drugalcdep.2010.10.009 PMID: 21111539 32. Haukkala A, Uutela A, Vartiainen E, McAlister A, Knekt P. Depression and smoking cessation: the role
of motivation and self-efficacy. Addict Behav. 2000; 25: 311–316. https://doi.org/10.1016/s0306-4603
(98)00125-7 PMID: 10795958 12 / 13 PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 PLOS ONE Smoking to relieve stress, motivation to stop and quit attempts 33. Berg CJ, An LC, Kirch M, Guo H, Thomas JL, Patten CA, et al. Failure to report attempts to quit smok-
ing. Addict Behav. 2010; 35: 900–904. https://doi.org/10.1016/j.addbeh.2010.06.009 PMID: 20584571 34. PLOS ONE | https://doi.org/10.1371/journal.pone.0268447
May 17, 2022 References Hughes JR, Solomon LJ, Naud S, Fingar JR, Helzer JE, Callas PW. Natural History of Attempts to Stop
Smoking. Nicotine Tob Res. 2014; 16: 1190–1198. https://doi.org/10.1093/ntr/ntu052 PMID: 24719491 35. Stone AA, Shiffman S. Ecological momentary assessment (EMA) in behavorial medicine. Ann Behav
Med. 1994; 16: 199–202. 36. Chaiton M, Diemert L, Cohen JE, Bondy SJ, Selby P, Philipneri A, et al. Estimating the number of quit
attempts it takes to quit smoking successfully in a longitudinal cohort of smokers. BMJ Open. 2016; 6:
e011045. https://doi.org/10.1136/bmjopen-2016-011045 PMID: 27288378 37. Sheals K, Tombor I, McNeill A, Shahab L. A mixed-method systematic review and meta-analysis of
mental health professionals’ attitudes toward smoking and smoking cessation among people with men-
tal illnesses. Addict Abingdon Engl. 2016; 111: 1536–1553. https://doi.org/10.1111/add.13387 PMID:
27003925 38. Shahab L, West R. Do ex-smokers report feeling happier following cessation? Evidence from a cross-
sectional survey. Nicotine Tob Res Off J Soc Res Nicotine Tob. 2009; 11: 553–557. https://doi.org/10. 1093/ntr/ntp031 PMID: 19351779 39. Shahab L, West R. Differences in happiness between smokers, ex-smokers and never smokers: cross-
sectional findings from a national household survey. Drug Alcohol Depend. 2012; 121: 38–44. https://
doi.org/10.1016/j.drugalcdep.2011.08.011 PMID: 21906891 40. Marghetis T, Attari SZ, Landy D. Simple interventions can correct misperceptions of home energy use. Nat Energy. 2019; 4: 874–881. https://doi.org/10.1038/s41560-019-0467-2 41. Cookson D, Jolley D, Dempsey RC, Povey R. A social norms approach intervention to address misper-
ceptions of anti-vaccine conspiracy beliefs amongst UK parents. PLOS ONE. 2021; 16: e0258985. https://doi.org/10.1371/journal.pone.0258985 PMID: 34767581 42. Finney Rutten LJ, Zhu X, Leppin AL, Ridgeway JL, Swift MD, Griffin JM, et al. Evidence-Based Strate-
gies for Clinical Organizations to Address COVID-19 Vaccine Hesitancy. Mayo Clin Proc. 2021; 96:
699–707. https://doi.org/10.1016/j.mayocp.2020.12.024 PMID: 33673921 43. Kotz D, West R. Explaining the social gradient in smoking cessation: it’s not in the trying, but in the suc-
ceeding. Tob Control. 2009; 18: 43–46. https://doi.org/10.1136/tc.2008.025981 PMID: 18936053 44. Smit ES, Hoving C, Schelleman-Offermans K, West R, de Vries H. Predictors of successful and unsuc-
cessful quit attempts among smokers motivated to quit. Addict Behav. 2014; 39: 1318–1324. https://doi. org/10.1016/j.addbeh.2014.04.017 PMID: 24837754 13 / 13
|
https://openalex.org/W4381486365
|
https://www.ozguryayinlari.com/site/catalog/download/128/639/1446
|
English
| null |
Artificial Intelligence (AI) and Ethics in Medicine at a Global Level: Benefits and Risks
|
Özgür Yayınları eBooks
| 2,023
|
cc-by
| 61,423
|
Editors Published by
Özgür Yayın-Dağıtım Co. Ltd. Certificate Number: 45503
15 Temmuz Mah. 148136. Sk. No: 9 Şehitkamil/Gaziantep
+90.850 260 09 97
+90.532 289 82 15
www.ozguryayınlari.com
info@ozguryayinlari.com Current Researches in Health Sciences-II
Editors: Dr. Enes Karaman • Dr. Gözde Özge Önder Current Researches in Health Sciences-II
Editors: Dr. Enes Karaman • Dr. Gözde Özge Önder Language: English
Publication Date: 2023
Cover design by Mehmet Çakır
Cover design and image licensed under CC BY-NC 4.0
Print and digital versions typeset by Çizgi Medya Co. Ltd. ISBN (PDF): 978-975-447-651-4 ISBN (PDF): 978-975-447-651-4 DOI: https://doi.org/10.58830/ozgur.pub128 This work is licensed under the Creative Commons Attribution-NonCommercial 4.0 International
(CC BY-NC 4.0). To view a copy of this license, visit https://creativecommons.org/licenses/by-nc/4.0/
This license allows for copying any part of the work for personal use, not commercial use, providing
author attribution is clearly stated. Suggested citation: gg
Karaman, E. (ed.) & Önder, G.Ö. (ed.) (2023). Current Researches in Health Sciences-II
DOI: https://doi.org/10.58830/ozgur.pub128. License: CC-BY-NC 4.0 The full text of this book has been peer-reviewed to ensure high academic standards. For full review policies, see
https://www.ozguryayinlari.com/ Preface Nowadays, at the point reached in the field of health, a lot of information
is rapidly emerging, changing and needs to be known. In addition, it is very
important
for
many
people
to
access
this
up-to-date
information
quickly. In this context, it is necessary to follow up-to-date information. Although
the
information
mentioned
in
the
book
are
current
issues,
each
of
them
is
supported
with
appropriate
visuals
to
make
it
easier
for
the
readers
to
understand. In addition, the chapters have been kept as short as possible in
accordance with the learning objective. We
would
like
to
thank
and
present
our
respects
to
the
authors
of
the chapters who contributed to the preparation of this book, believing
that it will contribute to the students of medicine, dentistry and biology, as
well as to those related to the field of health, since this book is easy to
understand. Dr. Enes Karaman
Dr. Gözde Özge Önder iii iii Contents iii Chapter 1 Exploring the Potential Therapeutic Approaches of Mesenchymal Stem/
Stromal Cells (MSCs) in the Treatment of Vaginal Candidiasis
1
Mesude Bicer Exploring the Potential Therapeutic Approaches of Mesenchymal Stem/
Stromal Cells (MSCs) in the Treatment of Vaginal Candidiasis Chapter 2 Hemoptysis
Elif Guliyev 19 The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and
Self-Esteem in Married Women with Physically Disabled
31
Türkan Akyol Güner
Chapter 4 The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and
Self-Esteem in Married Women with Physically Disabled
31
Türkan Akyol Güner The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and
Self-Esteem in Married Women with Physically Disabled
31
Türkan Akyol Güner
Chapter 4 Chapter 8 103 Orexinergic System and Antinociception
Ercan Özdemir Chapter 7 The Impact of Biochemical Alterations in the Tumor Microenvironment on
Cancer Progression and Treatment
85 Seyhan Turk Chapter 6 Chapter 6 Current Treatment Methods for Carpometacarpal Joint Fractures and
Dislocations
73
Eşref Selçuk 73 Dislocations
Eşref Selçuk Chapter 9 Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in
Perinatal Medicine
119
Rauf Melekoğlu
Ayşe Şebnem Erenler Chapter 10 Targeting the SH2 Domain of STAT3 Proteins in Breast Cancer Treatment 143
Busra Demir Cetinkaya Chapter 4 ntelligence (AI) and Ethics in Medicine at a Global Level: Benefits Artificial Intelligence (AI) and Ethics in Medicine at a Global Level: Benefits
and Risks
51
Sadi Elasan
Yusuf Ateş 51 Sadi Elasan
Yusuf Ateş Chapter 5 Childhood Hypertension
Gizem Gencan Childhood Hypertension
Gizem Gencan 63 v 1
Dr. Öğretim Görevlisi, Abdullah Gül University, Bioengineering Department,
mesude.bicer@agu.edu.tr, ORCID ID: 0000-0001-7089-5661 Abstract Over the past few decades, there has been significant progress in understanding
MSC therapy and its antimicrobial effects, leading to a substantial body
of literature in this field. MSC-based therapy has emerged as a charming
option for treatment modalities, serving as a cellular rehabilitative therapy
for various diseases, particularly inflammatory conditions. Despite several
clinical trials examining MSC-based therapies to struggle bacterial infections,
there are currently insufficient studies specifically focused on vaginal
candidiasis. The feasibility of autologous MSC and their targeted delivery
to specific cells has resulted in their extensive utilization across various
treatment fields. Although there are existing limitations, the transplantation
of MSCs represents a remarkable and inspiring approach in the scope of
medical science, necessitating further data collection to explore their potential
in addressing vaginal candidiasis. Further efforts are warranted to improve
efficient therapy using MSCs in therapeutic approaches. Depending upon
the findings in pre-clinical experiments, it is crucial to further investigate the
antifungal activities of MSCs and conduct translational studies to appreciate
their clinical applications. This concise chapter aims to promote such
endeavours in the remedial approaches of MSC for the treatment of vaginal
candidiasis. Chapter 11 161 A General Overview of Epilepsy: its Classification, and Management
161
Yavuz Yücel
Nor Osman Sidow169 A General Overview of Epilepsy: its Classification, and Management
161
Yavuz Yücel
Nor Osman Sidow169 A General Overview of Epilepsy: its Classification, and Management
161
Yavuz Yücel
Nor Osman Sidow169 vi Chapter 1 Exploring the Potential Therapeutic Approaches
of Mesenchymal Stem/Stromal Cells (MSCs) in
the Treatment of Vaginal Candidiasis Exploring the Potential Therapeutic Approaches
of Mesenchymal Stem/Stromal Cells (MSCs) in
the Treatment of Vaginal Candidiasis Mesude Bicer1 1.Introduction Candida spp. are widely recognized as the predominant etiological agents
responsible for fungal infections, ranging from severe invasive forms to
less critical mucocutaneous manifestations. Within Candida spp., Candida https://doi.org/10.58830/ozgur.pub128.c687 1 1 2 | Exploring the Potential Therapeutic Approaches of Mesenchymal Stem/Stromal Cells... 2 | 2 albicans holds a prominent position as the most prevalent causative organism
(Richards et al. 2000). Notably, Candida albicans exhibits a dual nature,
acting as a commensal microorganism in individuals with normal health
status while posing a substantial risk for morbidity and mortality in human
populations (Quindós 2014). This dimorphic yeast species demonstrates
a commensal nature by inhabiting the skin, gastrointestinal tract and
reproductive tracts of humans. Non-C. albicans species also have recognition
receptors that are capable of colonizing various mucocutaneous surfaces in
the human body (Sobel 2006). Furthermore, mucosal candidiasis, including
vaginal candidiasis, is very common diseases. It has been estimated that a
remarkable proportion of women, more than 75%, experience vulvovaginal
candidiasis at least once in their lifetime (Aguin and Sobel 2015). In addition,
approximately 5–10% of women suffer from recurrent episodes of vaginal
candidiasis (Weissenbacher et al. 2009). While Candida albicans is the most
primarily identified agent in invasive candidiasis, it has been a rise in the
incidence of candidiasis caused by non-Candida species, including Candida
krusei and Candida glabrata, Candida parapsilosis (Puig-Asensio et al. 2014). Additionally, Candida auris has become universally common among
nosocomial pathogens (Chowdhary et al. 2018). The pathogenesis and
diagnostic approaches for candida colonization are influenced by the host’s
immune status and display numerous variations depending on the clinical
indications of the disease. In terms of therapeutic interventions, the range of
antifungal agents accessible for the therapy of patients with invasive fungal
illnesses is restricted. Despite the advancement of current antifungal drugs,
the treatment options for systemic fungal diseases are constrained, leading to
unfavourable outcomes in many cases (Scriven et al. 2017). These emerging
Candida species often exhibit diminished susceptibility to commonly
employed antifungal agents utilized for the treatment of such infections. Examples of these drugs include fluconazole, micafungin, echinocandins,
anidulafungin, and caspofungin (Arendrup and Patterson 2017; Chowdhary
et al. 2018). Vaginal candidiasis is still an unresolved problem in society. Various factors contributing to the inefficacy of these drugs have been
identified, including several molecular resistance mechanisms (Arendrup
2014; Dominique Sanglard 2016). 1.Introduction Notably, these resistance mechanisms
are closely linked to elevated resistance against antifungal drugs and the
host’s immune-related factors, consequently leading to treatment failure
(Muzny and Schwebke 2015). Novel antifungal agents are urgently needed | 3 Mesude Bicer Mesude Bicer 3 (MSCs) and their possibilities to treat fungal candidiasis, particularly in
cases where conventional antifungal drugs have proven unsuccessful. MSCs
possess notable anti-inflammatory and immunomodulatory mechanisms
that can contribute to the resolution of fungal infectious episode (Schmidt
et al. 2017), although their precise role in the context of vaginal infections
remains incompletely understood. Thus, this chapter focuses on elucidating
the therapeutic properties of MSCs and their antifungal activity against
vaginal candidiasis. 2.1. The Pathogenesis When Candida is present in the vaginal region without concurrent
immunosuppression or mucosal damage, it typically does not manifest any
disease-related symptoms and is hereby referred to as fungal alignment. On
the contrary, vulvovaginal candidiasis can be characterized by the presence
of Candida spp. accompanied by signs and symptoms of inflammation,
indicating causative contagious agents. More than ten years ago, vulvovaginal
candidiasis was divided into two groups: uncomplicated and complicated
cases, which have gained international acceptance and verification (Pappas
et al. 2009). Uncomplicated vulvovaginal candidiasis refers to sporadic
occurrences, primarily caused by C. albicans, in immunocompetent women. On the other part, complicated vulvovaginal candidiasis encompasses
severe cases of the infection associated with factors such as pregnancy,
immunosuppression and uncontrolled diabetes (Sobel et al. 1998). Women
who suffer from recurrent episodes of vulvovaginal candidiasis constitute a
distinct subgroup within the healthy individuals, setting them apart from
those who have sporadic cases of vulvovaginal candidiasis. In comparison to
women with chronic vaginal symptoms unrelated to recurrent candidiasis, it
has been observed that the symptoms experienced by women with recurrent
vulvovaginal candidiasis have the most significant adverse effects on their
occupational and social functioning (Nyirjesy et al. 2006). During the initial phases of fungal pathogenesis, particularly in the case of
Candida albicans, it has been demonstrated that these pathogens exploit host
immune cells, impairing the early induction of proinflammatory cytokines,
thereby diminishing their expression. Regardless of how, the immune
response becomes intensified in the later phases of Candida diseases. A
recent investigation focusing on C. albicans elucidated that pathogenic fungi
downregulate the host immune response during the infections (Halder et 4 | Exploring the Potential Therapeutic Approaches of Mesenchymal Stem/Stromal Cells... al. 2020). This study indicated that C. albicans complies with monocytes
through the interaction between its β-glucan and the C3 receptor. By
utilizing this involvement to the monocytes, the fungal pathogens induce to
secrete proinflammatory cytokines containing transforming growth factor
(TGF)-β. These TGF-β-carrying proteins enable the pathogens to dampen
the immune response and exert anti-inflammatory effects. Furthermore, the
fungal pathogens can suppress the activation of these proteins by means of
secreting TGF- β (Netea et al. 2002; Halder et al. 2020). This mechanism
allows the fungal pathogens to suppress the immune response in the host,
favouring their own survival and persistence. 2.2. Epidemiology Estimating the global incidence of invasive candidiasis poses challenges
due to variations in diagnostic criteria and categorization methods employed. Many factors influence the incidence of this condition, including patients’
age, overall health status, the prevalence of immunodeficiency disorders,
frequency of organ transplantations, extent of major surgeries and utilization
of cancer chemotherapy. It is significant to give due consideration to factors
such as genetics, immunity, behavior, nutrition and others. In fact, the scarcity
of population- based surveys initiatives significantly limits our understanding
of the epidemiological surveillance of fungal candidiasis worldwide (Lamoth
et al. 2018). The incidence of Candida species observed in females diagnosed
with vaginal candidiasis exhibits significant variability across different
geographic locations and studied populations. Characteristically, a single
Candida species is described. However, in a small proportion of women
(approximately 2% to 5%) with both complicated and uncomplicated
vulvovaginal candidiasis, more than one species has been detected within
the self-similar vaginal culture (Richter et al. 2005). Examining Australia,
Europe and the United States of America, C. albicans is the most prevalent
pathogens defined in patients with vulvovaginal candidiasis, accounting
for approximately 76% to 89% of cases. This is followed by C. glabrata,
which represents approximately 7% to 16% of cases. Non-C. albicans species
collectively constitute 11% to 24% of vulvovaginal candidiasis cases within
these countries and regions (Spinillo et al. 1997; Holland et al. 2003;
Richter et al. 2005). Numerous studies have indicated an upward trend in the incidence of
invasive candidiasis within the United States of America when compared to
Australia, Latin America, Europe and Canada. Population-based studies in the
United States of America have reported incidences ranging from 9.5 to 26.2
cases of invasive candidiasis per 100,000 participants (Cleveland et al. 2015). e Bicer | 5 | 5 5 Mesude Bicer Mesude Bicer Mesude Bicer In contrast, most European countries including Iceland (Asmundsdottir
et al. 2013), France (Bitar et al. 2014), Sweden (Ericsson et al. 2013),
Norwegian (Hesstvedt et al. 2015) and Finland (Poikonen et al. 2010),
have reported lower incidences of 2.9 to 5.7 cases per 100,000 population. Interestingly, Spain and Denmark have both reported incidences exceeding
8 cases of candidemia per 100,000 populations (Arendrup et al. 2011; Puig-
Asensio et al. 2014). Australia and Canada exhibit candidemia rates that are
similar to those observed in European surveillance, with incidences of nearly
3 cases per 100,000 participants (St-Germain et al. 2008; Chapman et al. 2017). 2.2. Epidemiology Furthermore, certain Asian and African countries have indicated
a higher prevalence of fungal species, particularly C. glabrata, in cases of
vulvovaginal candidiasis. The distribution of Candida sp. in China closely
resembles that observed in the United States. (Holland et al. 2003; Richter
et al. 2005). Higher rates of non-C. albicans species have also been observed
in specific populations such as HIV-infected women (Spinillo et al. 1997),
postmenopausal women, and women with uncontrolled diabetes, regardless
of HIV infection (de Leon et al. 2002). Interestingly, an association has
been observed between increasing age and a higher proportion of other
Candida species in females with vulvovaginal candidiasis (Holland et al. 2003). C. glabrata is the most commonly isolated among all species. These
findings underscore the prominence of identifying Candida species and their
sensibilities in high-risk females with both C. albicans and non-C. albicans
vulvovaginal candidiasis in order to ensure influential treatment strategies. 2.3. Antifungal Resistance of Candida species from Vaginal
Candidiasis The treatment of Candida species presents a distinct challenge due
to their inherent resistance mechanisms, necessitating substantially
higher concentrations of antifungal drugs compared to planktonic cells
(Barantsevich and Barantsevich 2022). These species have developed
resistance through various mechanisms, including nutrient sensing, glucose
starvation, and heightened oxidative stress responses, enabling their survival
in the presence of antifungal components that trigger the concentration of
reactive oxygen species (ROS) (Lopes and Lionakis 2022; Brown 2023). Candida isolates obtained from vaginal samples exhibit some resistance
patterns that are resilient to antifungal agents in patients with candidiasis. Specially, a remarkable proportion of C. glabrata strains display resistance to
fluconazole, particularly in cases where patients have indwelling catheters,
resulting in fungal infections characterized by C. glabrata embedded in
biofilms. Instead of the resistance to fluconazole Candida cells related 6 Exploring the Potential Therapeutic Approaches of Mesenchymal Stem/Stromal Cells... 6 to biofilm often illustrate a high level of resistance to azoles, including
amphotericin B (AmB) (Sobel et al. 2000). Fluconazole is commonly preferred as a first-choice antifungal therapy
to combat mucosal candidiasis, caused by Candida albicans and Candida
parapsilosis. However, resistance to fluconazole is widely distributed
among various Candida species, such as Candida auris, Candida krusei and
Candida glabrata. These strains display high level of minimum inhibitory
concentrations (MICs) for fluconazole (>64mg/L), indicating resistance
to the antifungal agents (Chowdhary et al. 2016). Besides, these species
can also exhibit resistance to other antifungal classes, including azoles,
amphotericin B and even echinocandins (Arendrup and Patterson 2017;
Chowdhary et al. 2018). The progress of antifungal resistance in Candida
species is subject to various molecular mechanisms, depending on target
gene mutation, enhancement of target expression, impaired intracellular
conversion of drugs, increased activity of efflux pumps and decreased uptake
of antifungal drugs (Jensen et al. 2015; D. Sanglard 2016). These alternatives
may support the improvement of novel antifungal drugs, the identification
of new applications for established drugs, the synergistic combination of
existing drugs, or the advancement of biological therapies targeting virulence
factors on Candida metabolism (McCarthy and Walsh 2017). It is pivotal to address the growing challenge posed by candidiasis, which
has infectious agents to exhibit resistance to conventional anti-fungal drugs. Despite the development in understanding of the mechanisms and treatment
strategies against candida infections, there is still a need to develop effective
alternative strategies to combat fungal pathogens (McCarthy and Walsh
2017). 2.3. Antifungal Resistance of Candida species from Vaginal
Candidiasis In this context, MSCs and their anti-fungal activity could provide
emerging evidence as a therapeutic option for the treatment of vaginal
candidiasis. 3. MSCs and Their Anti-fungal Activity MSCs can be obtained from a variety of origins such as placenta,
adipose tissue, Wharton’s jelly, bone marrow, uterus, umbilical cord,
dermis, amniotic fluid, peripheral blood, periosteum, skeletal muscle and
dental pulp (Vizoso et al. 2017). In accordance with the “International
Society for Cellular Therapy” , it has been defined that MSCs exhibit the
following characteristics: (i) adherence to plastic surfaces (ii) expression
of specific stem cell markers (e.g., CD29, CD44, CD73, CD90 and
CD105), while lacking expression for hematopoietic markers (CD45 and
CD14), endothelial markers (CD31 and CD34) and also HLA-DR surface Mesude Bicer | 7 r | 7 | 7 Mesude Bicer | 7 Mesude Bicer molecules, and (iii) the ability to be speciliazed in vitro into chondroblastic,
osteoblastic and adipocytic cells (Dominici et al. 2006). MSCs have a
specific talent for differentiating into multiple cell lineages and displaying
widely immunomodulatory characteristics towards the congenital and
acquired immune system. These properties are modulated by the release of
soluble factors, including interleukins (IL) and interferons (IFN) (Zhang
et al. 2020; Oh et al. 2021). Both clinical and experimental studies have
supported the immunosuppressive capabilities of MSCs to treat a variety
of invasive autoimmune illnesses. MSCs have been shown to downregulate
the immune cells, such as B and T lymphocytes, natural killer (NK) cells
and dendritic cells (Aggarwal and Pittenger 2005). MSCs can also secrete
soluble proteins including interleukin-10 (IL-10), tumor necrosis factor- α
(TNF-α), prostaglandin E2 (PGE2), indoleamine 2,3-dioxygenase (IDO),
and interleukin-17, by which these proteins potentiate their antimicrobial
effects (Yang et al. 2013; Alcayaga-Miranda et al. 2017). Up to the present, stem cell-based therapy has shown promise in the
treatment of immune diseases. While significant progress has been made
in utilizing MSCs to address infectious diseases and their associated
complications, there is limited research focusing on their potential as a host
response against fungal infections (Keshtkar et al. 2022). Several cytokines
that are expressed at high levels have been identified to possess antifungal
potentials, including Chemokine (C-C motif) ligand (CCL- 5 and CCL-
6), IL-6, IL-8 and IL-17. Among them, IL-17 plays an important role in
mucocutaneous syndrome to tackle Candida albicans (Ling et al. 2015). Although the conventional mechanism of cytokine action involves cell
signaling based on immune system, supporting document suggests that
cytokines can be directly exerted to disrupt fungal pathogens. 3. MSCs and Their Anti-fungal Activity Notably, a
study has shown that IL-17 can attach to the receptor of Candida albicans,
leading to the prevention of fungal growth (Zelante et al. 2012). Moreover,
Li et al. have observed that IL-17 exhibits a direct inhibitory effect on the
proliferation of various eukaryotic cells, including neural stem cells, leading
to a significant decrease in the number of neural precursor cells. Although
purely and simply hypothesis, it is plausible that same inhibitory effect may
occur against Candida cells. Thus, apart from its known proinflammatory
function through immune system activation, IL-17 might also be exerted
to restrain the proliferation of Candida cell (Li et al. 2013). In the context
of adipose stem cells, specifically human umbilical cord-derived MSCs
(hUCESCs), studies have shown elevated levels of IL-17. This heightened
interleukin production with antifungal properties is not a characteristic
observed in all MSCs, but rather a distinct feature of hUCESCs, likely Exploring the Potential Therapeutic Approaches of Mesenchymal Stem/Stromal Cells... 8 8 developed as an evolutionary response to Candida strains in the vagina,
particularly in the conversion part of the cervix (Schneider et al. 2016). Consequently, the use of stem cells other than conventional drugs for the
treatment of vaginal candidiasis may potentially be quite effective. 4. The Therapeutic Applications of MSCs against Vaginal
Candidiasis Within the scope of innate
immunity, antimicrobial peptides (AMPs) play a crucial role by exerting
antimicrobial effects and modulating the immune system, thereby reducing
pathogen virulence (de Oca 2013). MSC have been found to directly
contribute to antimicrobial activity through the release of AMPs. These
peptides can induce the destruction of membrane integrity in microbial
cells and interact with peculiar intracellular adhesion molecules to combat
microbial agents (Alcayaga-Miranda et al. 2017; Marrazzo et al. 2019; Yagi
et al. 2020). Several AMPs have been identified as effective against Candida,
including human beta-Defensins (HBD), histatins, cathelicidin LL-37
Peptide (Edgerton et al. 1998; Joly et al. 2004; López-García et al. 2005). LL-37, in particular, exhibits a wide range of antimicrobial effect against
both bacterial and fungal diversity as well as viral diseases (López-García et
al. 2005; Peter et al. 2007; Wang et al. 2019). Multiple investigations have
demonstrated the talent of LL-37 to disrupt the cellular membrane and lipid
vesicles of certain bacteria (Henzler-Wildman et al. 2004). LL-37 has also
been demonstrated to interact with the cell wall of C. albicans (Tsai et al. 2011). These findings match a study by den Hertog et al., which indicated
that LL-37 can interfere in planktonic C. albicans to disrupt the plasma
membrane and the cell wall of fungal cells (Hertog et al. 2006). Another
study showed an efficient antifungal activity of LL-37 against C. albicans
(López-García et al. 2005). HBD also possess fungicidal activity against
C. albicans (Joly et al. 2004). In the presence of C. albicans, an increase in
HBD-2 level was observed in the female genital tract (Kotani et al. 2020). These findings have shown a positive correlation between the presence of
Lactobacillus and Candida spp., and the activity of HBD-2. Moreover,
HBD-2 has shown efficacy in decreasing the amount of fungus in a mouse
model of vaginal candidiasis (Liao et al. 2017). Emerging clinical research has indicated the significant involvement of
MSCs in antimicrobial activity. MSC therapy has also shown efficacy in
facilitating prompt control in patients with invasive Aspergilllus infections,
under the favour of hematopoietic stem cell transplantation (Ozdoğu et al. 2014). Investigations have indicated the efficiency of human cathelicidin
LL-37 and its parts LL13-37 and LL17-37, in which this AMP displays
comparable potency to restrain the growth of C. albicans. However, the
death of C. 4. The Therapeutic Applications of MSCs against Vaginal
Candidiasis 4. The Therapeutic Applications of MSCs against Vaginal
Candidiasis The NIH Clinical Trial Database currently contains over 1000 registered
clinical trials focused on MSC therapy. Among these trials, approximately
47.1% (491 trials) are specifically targeting immune disorders. Within this
subgroup, there are 2 trials focused on fungal infections and 5 trials conducted
on infected individuals with vaginal diseases (source: https://ClinicalTrials. gov/ ; accessed on 8 June 2023). The trials addressing fungal and vaginal
diseases primarily involve the transplantation of autologous or allogeneic
MSC through local injection to treat some diseases including fistulas,
rectovaginal fistulas, and Crohn’s disease of vulva. Allogeneic MSC are
more commonly used due to their ability to be expanded in large quantities
and fully characterized before administration, offering greater convenience
in terms of cell dose availability. MSCs possess the capability to react to
immune response in the host and also release various soluble factors, leading
to immunomodulatory properties. As a result, the therapeutic potential of
MSCs has evolved from primarily focusing on their regenerative effects to
encompassing their anti-inflammatory properties, as well as other notable
attributes such as angiogenesis promotion, anti-oxidative stress effects, anti-
tumoral and antimicrobial activities (Fernández-Francos et al. 2021). Certain sources of MSC have gained attention for their potential in specific
therapeutic indications. For instance, MSC sourced from reproductive
tissues have shown promise in terms of their anti-tumor activity (Schneider
et al. 2016). hUCESCs have been recognized for their immunomodulatory
properties (Eiró et al. 2014), while MSC derived from dental pulp have
demonstrated potential in addressing neurological disorders (Apel et al. 2009). The regenerative effects of MSC have been primarily attributed to
paracrine signaling (Bluguermann et al. 2013), whereby MSCs also release
a range of growth factors, which comprise vascular endothelial growth
factor, platelet-derived growth factor, fibroblast growth factor as well as
transforming growth factor (TGF-β1 and TGF-α), among others. These
factors contribute to the increased proliferation of endothelial cells as well
as their proliferation (Park et al. 2018; Ahangar et al. 2020). In addition
to, MSCs have been reported to encourage the survival and reinforce the | 9 | 9 Mesude Bicer regeneration of epithelial cells in the colon, by means of EVs including
growth factors and cytokines (Shi et al. 2019; Sendon-Lago et al. 2021). The immune response of the human body includes innated and acquired
immune responses to combat infections. 4. The Therapeutic Applications of MSCs against Vaginal
Candidiasis albicans cells may also be attributed to other intracellular targets
as well as LL13-37 fragments (Wong et al. 2011). In the case of patients Exploring the Potential Therapeutic Approaches of Mesenchymal Stem/Stromal Cells... 10 with agonising neutrophilic bronchial asthma, implementation of MSCs
has been shown as a promising treatment by reducing Aspergillus-induced
inflammation and improving diseases symptoms with the help of detention
of the Th17 signaling pathway (Lathrop et al. 2014). Collectively, subsets
of MSCs displaying the aforementioned characteristics hold potential to
be valuable candidates for addressing and combating infectious diseases. Further validations of these findings through additional research may open
new avenues for innovative therapeutic strategies aimed at addressing vaginal
candidiasis. 5. Conclusion Vaginal candidiasis is a type of infectious diseases that is closely associated
with the pathogenic mechanism of microorganism and is susceptible to a
wide range of infectious pathogens due to its unique microbiome. Within
this context, the follow-up of MSC-based therapy has the potential to
influence the development, progression, prevention and containment of the
disease. MSCs also play a remarkable role in regulating the host immune
system in microbial infections. Furthermore, MSCs can be employed in the
diagnosis of infectious diseases. Considering the significance of addressing
vaginal infectious diseases and the convenience of using cell-based therapies,
MSCs can be regarded as a viable and accessible option for the treatment
of vaginal candidiasis. However, further extensive studies are needed in the
future to explore their full potential and efficacy in this context. The pathogenesis of Candida species is complex, posing challenges in
finding an effective therapeutic strategy that comprehensively deals with
various clinical applications. The therapeutic potential of MSCs has evolved
over time, transitioning from autologous to allogeneic MSC applications
and from the initial focus on their remedial effects to encompass anti-
inflammatory, anti-tumor, antimicrobial and anti-oxidative stress properties. These advancements in understanding open up new possibilities for
developing therapeutic strategies for vaginal candidiasis. MSCs have
demonstrated the ability to counteract fungal infections, suggesting their
potential as a defence mechanism against vaginal infections. Incorporating
nanotechnology-based advancements can further optimize MSC-based
therapeutic applications in clinical practice. These advancements pave the
way for designing innovative therapeutic approaches against the diverse and
intricate therapeutic targets associated with vaginal candidiasis using cell-
based therapies. Mesude Bicer | 11 References Aggarwal S, Pittenger MF (2005) Human mesenchymal stem cells modulate
allogeneic immune cell responses. Blood 105: 1815-1822 Aguin TJ, Sobel JD (2015) Vulvovaginal Candidiasis in Pregnancy. Current In-
fectious Disease Reports 17: 30 Ahangar P, Mills SJ, Cowin AJ (2020) Mesenchymal Stem Cell Secretome as an
Emerging Cell-Free Alternative for Improving Wound Repair. Internati-
onal journal of molecular sciences 21: 7038 Alcayaga-Miranda F, Cuenca J, Khoury M (2017) Antimicrobial Activity of Me-
senchymal Stem Cells: Current Status and New Perspectives of Antimic-
robial Peptide-Based Therapies. Frontiers in Immunology 8: Apel C, Forlenza OV, de Paula VJR, Talib LL, Denecke B, Eduardo CP, Gattaz
WF (2009) The neuroprotective effect of dental pulp cells in models of
Alzheimer’s and Parkinson’s disease. Journal of Neural Transmission 116:
71-78 Arendrup MC (2014) Update on antifungal resistance in <em>Aspergillus</
em> and <em>Candida</em>. Clinical Microbiology and Infection
20: 42-48 Arendrup MC, Patterson TF (2017) Multidrug-Resistant Candida: Epidemio-
logy, Molecular Mechanisms, and Treatment. The Journal of Infectious
Diseases 216: S445-S451 Arendrup MC, Bruun B, Christensen JJ, Fuursted K, Johansen HK, Kjældgaard
P, Knudsen JD, Kristensen L, Møller J, Nielsen L, Rosenvinge FS, Røder
B, Schønheyder HC, Thomsen MK, Truberg K (2011) National Sur-
veillance of Fungemia in Denmark (2004 to 2009). Journal of Clinical
Microbiology 49: 325-334 Asmundsdottir LR, Erlendsdottir H, Gottfredsson M (2013) Nationwide study
of candidemia, antifungal use, and antifungal drug resistance in Iceland,
2000 to 2011. J Clin Microbiol 51: 841-848 Barantsevich N, Barantsevich E (2022) Diagnosis and Treatment of Invasive
Candidiasis. Antibiotics 11: 718 Bitar D, Lortholary O, Le Strat Y, Nicolau J, Coignard B, Tattevin P, Che D,
Dromer F (2014) Population-based analysis of invasive fungal infections,
France, 2001-2010. Emerg Infect Dis 20: 1149-1155 Bluguermann C, Wu L, Petrigliano F, McAllister D, Miriuka S, Evseenko DA
(2013) Novel aspects of parenchymal–mesenchymal interactions: from
cell types to molecules and beyond. Cell Biochemistry and Function 31:
271-280 Brown AJP (2023) Fungal resilience and host–pathogen interactions: Future
perspectives and opportunities. Parasite Immunology 45: e12946 12 | Exploring the Potential Therapeutic Approaches of Mesenchymal Stem/Stromal Cells... References Chapman B, Slavin M, Marriott D, Halliday C, Kidd S, Arthur I, Bak N, Heath
CH, Kennedy K, Morrissey CO, Sorrell TC, van Hal S, Keighley C, Go-
eman E, Underwood N, Hajkowicz K, Hofmeyr A, Leung M, Macesic
N, Botes J, Blyth C, Cooley L, George CR, Kalukottege P, Kesson A,
McMullan B, Baird R, Robson J, Korman TM, Pendle S, Weeks K, Liu
E, Cheong E, Chen S (2017) Changing epidemiology of candidaemia in
Australia. J Antimicrob Chemother 72: 1103-1108 Chowdhary A, Voss A, Meis JF (2016) Multidrug-resistant Candida auris: ‘new
kid on the block’ in hospital-associated infections? J Hosp Infect 94:
209-212 Chowdhary A, Prakash A, Sharma C, Kordalewska M, Kumar A, Sarma S, Tarai
B, Singh A, Upadhyaya G, Upadhyay S, Yadav P, Singh PK, Khillan V,
Sachdeva N, Perlin DS, Meis JF (2018) A multicentre study of antifun-
gal susceptibility patterns among 350 Candida auris isolates (2009–17)
in India: role of the ERG11 and FKS1 genes in azole and echinocandin
resistance. Journal of Antimicrobial Chemotherapy 73: 891-899 Cleveland AA, Harrison LH, Farley MM, Hollick R, Stein B, Chiller TM, Lo-
ckhart SR, Park BJ (2015) Declining incidence of candidemia and the
shifting epidemiology of Candida resistance in two US metropolitan are-
as, 2008-2013: results from population-based surveillance. PLoS One
10: e0120452 de Leon EM, Jacober SJ, Sobel JD, Foxman B (2002) Prevalence and risk fac-
tors for vaginal Candida colonization in women with type 1 and type 2
diabetes. BMC Infect Dis 2: 1 de Oca EPM (2013) Antimicrobial peptide elicitors: New hope for the post-an-
tibiotic era. Innate Immunity 19: 227-241 Dominici M, Le Blanc K, Mueller I, Slaper-Cortenbach I, Marini FC, Krause
DS, Deans RJ, Keating A, Prockop DJ, Horwitz EM (2006) Minimal
criteria for defining multipotent mesenchymal stromal cells. The Inter-
national Society for Cellular Therapy position statement. Cytotherapy 8:
315-317 Edgerton M, Koshlukova SE, Lo TE, Chrzan BG, Straubinger RM, Raj PA
(1998) Candidacidal Activity of Salivary Histatins: IDENTIFICATION
OF A HISTATIN 5-BINDING PROTEIN ON <em>Candida albi-
cans</em> *. Journal of Biological Chemistry 273: 20438-20447 Eiró N, Sendon-Lago J, Seoane S, Bermúdez MA, Lamelas ML, Garcia-Ca-
ballero T, Schneider J, Perez-Fernandez R, Vizoso FJ (2014) Potential
therapeutic effect of the secretome from human uterine cervical stem cells
against both cancer and stromal cells compared with adipose tissue stem
cells. References Oncotarget 5: 10692-10708 | 13 13 Mesude Bicer Ericsson J, Chryssanthou E, Klingspor L, Johansson AG, Ljungman P, Svensson
E, Sjölin J (2013) Candidaemia in Sweden: a nationwide prospective ob-
servational survey. Clin Microbiol Infect 19: E218-221 Fernández-Francos S, Eiro N, Costa LA, Escudero-Cernuda S, Fernández-Sánc-
hez ML, Vizoso FJ (2021) Mesenchymal Stem Cells as a Cornerstone in
a Galaxy of Intercellular Signals: Basis for a New Era of Medicine. Inter-
national journal of molecular sciences 22: 3576 Halder LD, Jo EAH, Hasan MZ, Ferreira-Gomes M, Krüger T, Westermann M,
Palme DI, Rambach G, Beyersdorf N, Speth C, Jacobsen ID, Kniemeyer
O, Jungnickel B, Zipfel PF, Skerka C (2020) Immune modulation by
complement receptor 3-dependent human monocyte TGF-β1-transpor-
ting vesicles. Nature Communications 11: 2331 Henzler-Wildman KA, Martinez GV, Brown MF, Ramamoorthy A (2004) Per-
turbation of the Hydrophobic Core of Lipid Bilayers by the Human An-
timicrobial Peptide LL-37. Biochemistry 43: 8459-8469 Hertog ALd, Marle Jv, Veerman ECI, Valentijn-Benz M, Nazmi K, Kalay H,
Grün CH, Hof Wvt, Bolscher JGM, Amerongen AVN (2006) The hu-
man cathelicidin peptide LL-37 and truncated variants induce segregati-
on of lipids and proteins in the plasma membrane of Candida albicans. 387: 1495-1502 Hesstvedt L, Gaustad P, Andersen CT, Haarr E, Hannula R, Haukland HH,
Hermansen NO, Larssen KW, Mylvaganam H, Ranheim TE, Sandven P,
Nordøy I, Kanestrøm A, Grub C, Onken A, Thielsen C, Skaare D, Tof-
teland S, Sønsteby LJ, Hjetland R, Hide R, Vik E, Kümmel A, Åsheim
S (2015) Twenty-two years of candidaemia surveillance: results from a
Norwegian national study. Clin Microbiol Infect 21: 938-945 Holland J, Young ML, Lee O, S CAC (2003) Vulvovaginal carriage of yeasts
other than Candida albicans. Sex Transm Infect 79: 249-250 Jensen RH, Astvad KM, Silva LV, Sanglard D, Jørgensen R, Nielsen KF, Mathi-
asen EG, Doroudian G, Perlin DS, Arendrup MC (2015) Stepwise emer-
gence of azole, echinocandin and amphotericin B multidrug resistance in
vivo in Candida albicans orchestrated by multiple genetic alterations. J
Antimicrob Chemother 70: 2551-2555 Joly S, Maze C, McCray PB, Guthmiller JM (2004) Human β-Defensins 2 and
3 Demonstrate Strain-Selective Activity against Oral Microorganisms. Journal of Clinical Microbiology 42: 1024-1029 Keshtkar S, Kaviani M, Soleimanian S, Azarpira N, Asvar Z, Pakbaz S (2022)
Stem Cell-Derived Exosome as Potential Therapeutics for Microbial Di-
seases. References Frontiers in Microbiology 12: Kotani H, Koshizuka T, Matsubara K, Nishiyama K, Sugiyama T, Suzutani T
(2020) Relationship Between Human β-Defensin 2 and the Vaginal En-
vironment. Japanese Journal of Infectious Diseases 73: 214-220 14 | Exploring the Potential Therapeutic Approaches of Mesenchymal Stem/Stromal Cells... 14 Lamoth F, Lockhart SR, Berkow EL, Calandra T (2018) Changes in the epi-
demiological landscape of invasive candidiasis. J Antimicrob Chemother
73: i4-i13 Lathrop MJ, Brooks EM, Bonenfant NR, Sokocevic D, Borg ZD, Goodwin M,
Loi R, Cruz F, Dunaway CW, Steele C, Weiss DJ (2014) Mesenchymal
stromal cells mediate Aspergillus hyphal extract-induced allergic airway
inflammation by inhibition of the Th17 signaling pathway. Stem Cells
Transl Med 3: 194-205 Li Z, Li K, Zhu L, Kan Q, Yan Y, Kumar P, Xu H, Rostami A, Zhang G-X
(2013) Inhibitory effect of IL-17 on neural stem cell proliferation and
neural cell differentiation. BMC Immunology 14: 20 Liao H, Liu S, Wang H, Su H, Liu Z (2017) Efficacy of Histatin5 in a murine
model of vulvovaginal candidiasis caused by Candida albicans. Pathogens
and Disease 75: Ling Y, Cypowyj S, Aytekin C, Galicchio M, Camcioglu Y, Nepesov S, Ikinci-
ogullari A, Dogu F, Belkadi A, Levy R, Migaud M, Boisson B, Bolze A,
Itan Y, Goudin N, Cottineau J, Picard C, Abel L, Bustamante J, Casanova
J-L, Puel A (2015) Inherited IL-17RC deficiency in patients with chro-
nic mucocutaneous candidiasis. Journal of Experimental Medicine 212:
619-631 Lopes JP, Lionakis MS (2022) Pathogenesis and virulence of Candida albicans. Virulence 13: 89-121 López-García B, Lee PHA, Yamasaki K, Gallo RL (2005) Anti-Fungal Activity
of Cathelicidins and their Potential Role in <em>Candida albicans</
em> Skin Infection. Journal of Investigative Dermatology 125: 108-115 Marrazzo P, Crupi AN, Alviano F, Teodori L, Bonsi L (2019) Exploring the
roles of MSCs in infections: focus on bacterial diseases. J Mol Med (Berl)
97: 437-450 McCarthy MW, Walsh TJ (2017) Drugs currently under investigation for the tre-
atment of invasive candidiasis. Expert Opin Investig Drugs 26: 825-831 Muzny CA, Schwebke JR (2015) Biofilms: An Underappreciated Mechanism
of Treatment Failure and Recurrence in Vaginal Infections. Clinical Infe-
ctious Diseases 61: 601-606 Netea MG, Stuyt RJL, Kim S-H, Van der Meer JWM, Kullberg BJ, Dinarello
CA (2002) The Role of Endogenous Interleukin (IL)-18, IL-12, IL-1β,
and Tumor Necrosis Factor-α in the Production of Interferon-γ Induced
by Candida albicans in Human Whole-Blood Cultures. References The Journal of
Infectious Diseases 185: 963-970 Nyirjesy P, Peyton C, Weitz MV, Mathew L, Culhane JF (2006) Causes of chro-
nic vaginitis: analysis of a prospective database of affected women. Obs-
tet Gynecol 108: 1185-1191 | 15 15 Mesude Bicer Mesude Bicer Oh S, Jang AY, Chae S, Choi S, Moon J, Kim M, Spiekerkoetter E, Zamanian
RT, Yang PC, Hwang D, Byun K, Chung W-J (2021) Comparative analy-
sis on the anti-inflammatory/immune effect of mesenchymal stem cell
therapy for the treatment of pulmonary arterial hypertension. Scientific
Reports 11: 2012 Ozdoğu H, Yeral M, Boğa C, Kozanoğlu I (2014) Use of mesenchymal cells to
modulate immune suppression and immune reconstruction in a patient
with aplastic anemia complicated by invasive sino-orbital aspergillosis. Turk J Haematol 31: 181-183 Pappas PG, Kauffman CA, Andes D, Benjamin DK, Jr., Calandra TF, Edwards
JE, Jr., Filler SG, Fisher JF, Kullberg BJ, Ostrosky-Zeichner L, Reboli
AC, Rex JH, Walsh TJ, Sobel JD (2009) Clinical practice guidelines for
the management of candidiasis: 2009 update by the Infectious Diseases
Society of America. Clin Infect Dis 48: 503-535 Park S-R, Kim J-W, Jun H-S, Roh JY, Lee H-Y, Hong I-S (2018) Stem Cell
Secretome and Its Effect on Cellular Mechanisms Relevant to Wound
Healing. Molecular Therapy 26: 606-617 Peter B, Lilian W-J, Kristina B, Birgitta A, Johan S (2007) The Antimicrobial
Peptide LL-37 Inhibits HIV-1 Replication. Current HIV Research 5:
410-415 Poikonen E, Lyytikäinen O, Anttila VJ, Koivula I, Lumio J, Kotilainen P, Syrjälä
H, Ruutu P (2010) Secular trend in candidemia and the use of flucona-
zole in Finland, 2004-2007. BMC Infect Dis 10: 312 Puig-Asensio M, Padilla B, Garnacho-Montero J, Zaragoza O, Aguado JM, Za-
ragoza R, Montejo M, Muñoz P, Ruiz-Camps I, Cuenca-Estrella M, Al-
mirante B (2014) Epidemiology and predictive factors for early and late
mortality in <em>Candida</em> bloodstream infections: a populati-
on-based surveillance in Spain. Clinical Microbiology and Infection 20:
O245-O254 Puig-Asensio M, Padilla B, Garnacho-Montero J, Zaragoza O, Aguado JM, Za-
ragoza R, Montejo M, Muñoz P, Ruiz-Camps I, Cuenca-Estrella M, Al-
mirante B (2014) Epidemiology and predictive factors for early and late
mortality in Candida bloodstream infections: a population-based surveil-
lance in Spain. Clin Microbiol Infect 20: O245-254 Quindós G (2014) Epidemiology of candidaemia and invasive candidiasis. A
changing face. References Revista Iberoamericana de Micología 31: 42-48 Richards MJ, Edwards JR, Culver DH, Gaynes RP (2000) Nosocomial infe-
ctions in combined medical-surgical intensive care units in the United
States. Infect Control Hosp Epidemiol 21: 510-515 Richter SS, Galask RP, Messer SA, Hollis RJ, Diekema DJ, Pfaller MA (2005)
Antifungal susceptibilities of Candida species causing vulvovaginitis and
epidemiology of recurrent cases. J Clin Microbiol 43: 2155-2162 16 | 16 | Exploring the Potential Therapeutic Approaches of Mesenchymal Stem/Stromal Cells... 16 Sanglard D (2016) Emerging Threats in Antifungal-Resistant Fungal Pat-
hogens. Frontiers in Medicine 3: Sanglard D (2016) Emerging Threats in Antifungal-Resistant Fungal Pat-
hogens. Front Med (Lausanne) 3: 11 Schmidt S, Tramsen L, Schneider A, Schubert R, Balan A, Degistirici Ö, Meisel
R, Lehrnbecher T (2017) Impact of human mesenchymal stromal cells
on antifungal host response against Aspergillus fumigatus. Oncotarget 8:
95495-95503 Schneider J, Eiró N, Pérez-Fernández R, Martínez-Ordóñez A, Vizoso F (2016)
Human Uterine Cervical Stromal Stem Cells (hUCESCs): Why and
How they Exert their Antitumor Activity. Cancer Genomics Proteomics
13: 331-337 Scriven JE, Tenforde MW, Levitz SM, Jarvis JN (2017) Modulating host im-
mune responses to fight invasive fungal infections. Current Opinion in
Microbiology 40: 95-103 Sendon-Lago J, Rio LG-d, Eiro N, Diaz-Rodriguez P, Avila L, Gonzalez LO,
Vizoso FJ, Perez-Fernandez R, Landin M (2021) Tailored Hydrogels as
Delivery Platforms for Conditioned Medium from Mesenchymal Stem
Cells in a Model of Acute Colitis in Mice. Pharmaceutics 13: 1127 Shi X, Chen Q, Wang F (2019) Mesenchymal stem cells for the treatment of
ulcerative colitis: a systematic review and meta-analysis of experimental
and clinical studies. Stem Cell Research & Therapy 10: 266 Sobel JD (2006) The emergence of non-albicans Candida species as causes of
invasive candidiasis and candidemia. Curr Infect Dis Rep 8: 427-433 Sobel JD, Faro S, Force RW, Foxman B, Ledger WJ, Nyirjesy PR, Reed BD,
Summers PR (1998) Vulvovaginal candidiasis: epidemiologic, diagnos-
tic, and therapeutic considerations. Am J Obstet Gynecol 178: 203-211 Sobel JD, Kauffman CA, McKinsey D, Zervos M, Vazquez JA, Karchmer AW,
Lee J, Thomas C, Panzer H, Dismukes WE (2000) Candiduria: a ran-
domized, double-blind study of treatment with fluconazole and placebo. The National Institute of Allergy and Infectious Diseases (NIAID) My-
coses Study Group. Clin Infect Dis 30: 19-24 Spinillo A, Capuzzo E, Gulminetti R, Marone P, Colonna L, Piazzi G (1997)
Prevalence of and risk factors for fungal vaginitis caused by non-albicans
species. 1
Dr., Kocaeli University, Faculty of Medicine, Department of Pulmonary Diseases, elifkrsl@
gmail.com, Orcid: 0000-0002-1501-3360 References Am J Obstet Gynecol 176: 138-141 St-Germain G, Laverdière M, Pelletier R, René P, Bourgault AM, Lemieux C,
Libman M (2008) Epidemiology and antifungal susceptibility of bloo-
dstream Candida isolates in Quebec: Report on 453 cases between 2003
and 2005. Can J Infect Dis Med Microbiol 19: 55-62 Mesude Bicer | 17 Bicer | 17 17 Mesude Bicer | 17 Mesude Bicer Mesude Bicer Tsai P-W, Yang C-Y, Chang H-T, Lan C-Y (2011) Characterizing the Role of Cell-
Wall β-1,3-Exoglucanase Xog1p in Candida albicans Adhesion by the Hu-
man Antimicrobial Peptide LL-37. PLOS ONE 6: e21394 Vizoso FJ, Eiro N, Cid S, Schneider J, Perez-Fernandez R (2017) Mesenchymal
Stem Cell Secretome: Toward Cell-Free Therapeutic Strategies in Rege-
nerative Medicine. International journal of molecular sciences 18: 1852 Wang G, Narayana JL, Mishra B, Zhang Y, Wang F, Wang C, Zarena D, Lus-
hnikova T, Wang X (2019) Design of Antimicrobial Peptides: Progress
Made with Human Cathelicidin LL-37. Antimicrobial Peptides: Basics for
Clinical Application,(Matsuzaki K, ed.) p.^pp. 215-240. Springer Singa-
pore, Singapore. Weissenbacher TM, Witkin SS, Gingelmaier A, Scholz C, Friese K, Mylonas I
(2009) Relationship between recurrent vulvovaginal candidosis and im-
mune mediators in vaginal fluid. European Journal of Obstetrics and Gy-
necology and Reproductive Biology 144: 59-63 Wong JH, Ng TB, Legowska A, Rolka K, Hui M, Cho CH (2011) Antifungal
action of human cathelicidin fragment (LL13-37) on Candida albicans. Peptides 32: 1996-2002 Yagi H, Chen AF, Hirsch D, Rothenberg AC, Tan J, Alexander PG, Tuan RS
(2020) Antimicrobial activity of mesenchymal stem cells against Staphy-
lococcus aureus. Stem Cell Research & Therapy 11: 293 Yang R, Liu Y, Kelk P, Qu C, Akiyama K, Chen C, Atsuta I, Chen W, Zhou Y,
Shi S (2013) A subset of IL-17+ mesenchymal stem cells possesses an-
ti-Candida albicans effect. Cell Research 23: 107-121 Zelante T, Iannitti RG, De Luca A, Arroyo J, Blanco N, Servillo G, Sanglard D,
Reichard U, Palmer GE, Latgè J-P, Puccetti P, Romani L (2012) Sensing
of mammalian IL-17A regulates fungal adaptation and virulence. Nature
Communications 3: 683 Zhang B, Tian X, Hao J, Xu G, Zhang W (2020) Mesenchymal Stem Cell-De-
rived Extracellular Vesicles in Tissue Regeneration. Cell Transplantation
29: 0963689720908500 Chapter 2 Chapter 2 Abstract Composed of two Greek words (“heima”-blood and “ptysis”-spitting),
hemoptysis is a symptom that alarms the patient. If the hemoptysis is
not massive, there is time to investigate the underlying disease. Massive
hemoptysis is life-threatening. It has serious mortality and morbidity. In
this article, the latest developments in the hemoptysis approach will be
discussed. Hemoptysis is the expectoration of blood or mixed secretions from the lower
respiratory tract. The amount may be small or in amounts that can cause
death. Sputum mixed with mucus, thick, sticky, blackish, and sour, is called
bloody sputum (hemopteic krasha). Life-threatening bleeding is defined as massive hemoptysis. Massive
hemoptysis, which constitutes 5-15% of all hemoptysis, requires urgent
intervention. For massive bleeding, different amounts are reported as 200-
1000 ml bleeding in 24 hours, more than 200 ml in 2 hours, and more than
600 ml in 24 hours in different sources. Definitions for this non-standardized
amount of bleeding do not always reflect the clinical characteristics of
the patient. For example, the acute situation caused by 200 mL blood
expectoration in the last 10 minutes, and 200 mL expectoration spread
throughout the day cause different clinical pictures and require different
interventions. For this reason, today, the definition is made by considering
the clinical characteristics of the patient. Any amount of hemoptysis leading to a life-threatening condition such as
respiratory failure or hypotension is recommended to be defined as massive
hemoptysis (life-threatening hemoptysis). https://doi.org/10.58830/ozgur.pub128.c507 https://doi.org/10.58830/ozgur.pub128.c507 19 19 20 | Hemoptysis 20 | Hemoptysis Pathophysiology Perfusion of the lungs; 95% is supplied from the pulmonary arteries
(right ventricle) and 5% from the bronchial arteries (the descending aorta
between T3-T8, most often from the T5-T6 level (80%), phrenic arteries,
subclavian arteries, intercostal arteries). 95% of pulmonary blood circulation
is provided by the pulmonary artery (functional role) and its branches, which
have a low-pressure system. Since the bronchial arteries (nutritional role) are supplied with blood
from the systemic arteries, blood pressure is high and this high pressure
increases the risk of massive bleeding. At the same time, the bronchial
arteries are the vessels that supply the airways and are affected by airway
lesions. Often (40%) there is one bronchial artery on the right and two
on the left. Various anatomical variations have been described in normal
healthy individuals (Figure-1). They may also have aberrant origins from
other systemic arteries (20%) Figure 1- Bronchial artery variations Figure 1- Bronchial artery variations Figure 1- Bronchial artery variations Type 1: 1 right Bronchial artery 2 left Bronchial arteries of the same
origin Type 2: 1 right Bronchial artery and 1 left Bronchial artery of the same
origin Type 3: 2 right Bronchial arteries and 2 left Bronchial arteries of the same
origin Type 4: 2 right Bronchial arteries of the same origin and 1 left Bronchial
artery, Bleeding in patients presenting with the complaint of hemoptysis;
originates from 90% bronchial arteries, 5% pulmonary arteries, 5% non-
bronchial systemic arteries, and very rarely pulmonary-bronchial veins and Elif Guliyev | 21 Elif Guliyev 21 capillaries. Pulmonary venous bleeding is usually mild and may occur in left
heart failure, mainly due to pulmonary venous hypertension. Bleeding due to the bronchial venous system can occur with proliferating
submucosal bronchial veins, often as a complication of mitral stenosis, may
be life-threatening, and may constitute an indication for surgical intervention. Hemoptysis occurs with the formation of capillary anastomoses
between the pulmonary artery and systemic bronchial arteries, pulmonary
thromboembolism, vasculitis, suppression of pulmonary circulation due to
hypoxic vasoconstriction, and an increase in bronchial flow. Hemoptysis
develops as a result of the widening of the vessels and thinning of their walls
due to excessive flow increase in these anastomoses. Pathophysiology On the other hand, the
change in vascular anatomy as a result of chronic inflammatory lung diseases
causes the bronchial arteries to expand and fold, and new collaterals are
formed with the clarification of normal anastomoses between the bronchial
arteries and pulmonary veins, and the release of angiogenic growth factors,
supporting neovascularization and pulmonary vascular remodeling. Hemoptysis develops as a result of an increase in collaterals and enlargement
and fragility of vessels. Causes of Hemoptysis The vast majority of cases of hemoptysis occur in adults. Although the
average age varies according to the underlying cause, hemoptysis due to
lung cancer is usually seen between the ages of 40-60. It is seen twice as
often in men than in women. The most common causes of hemoptysis are pulmonary tuberculosis,
bronchial cancer, bronchiectasis, pneumonia, vasculitic syndromes,
and pulmonary infarction. In our country, Fidan et al. and Ünsal et al.,
bronchiectasis, tuberculosis, and lung cancer were reported as the three
most common causes. On the other hand, up to 50% of cases of unknown-
cryptogenic hemoptysis are reported worldwide. In pulmonary tuberculosis, massive bleeding may occur with the rupture
of Rasmussen aneurysms in the cavity wall. Aspergillus infection is the most
common fungal agent that settles in the cavity wall and causes hemoptysis in
our country. In pulmonary edema; The patient has hemoptysis in the form
of pink foamy sputum, and the patient has severe dyspnea, orthopnea, and
heart failure findings. The causes of hemoptysis are listed in Table 1. Bleeding seen in bronchiectasis originates from the bronchial artery
and can be serious. It can also be traumatic or iatrogenic hemoptysis. In 22 Hemoptysis alveolar hemorrhages; While hemoptysis is seen immunologically, periodic
hemoptysis “catamenial hemoptysis” may occur in the menstrual cycle due
to ectopic endometrium in women. Despite all possibilities, the cause of
hemoptysis cannot be determined in 50% of the cases. The prognosis is
generally good in idiopathic hemoptysis, but it may recur. Table 1- Conditions causing hemoptysis
Infections:
Tuberculosis
Fungal infections
Lung abscess
Bronchiectasis/Bronchitis
Neoplasm:
Bronchogenic carcinoma
Pulmonary metastases
Carcinoid
Medication (VEGF etc.)
Vascular/itis:
Pulmonary embolism
AV malformations
Wegener’s granulomatosis
Left heart failure
Coagulopathy:
Anticoagulant therapy
Platelet dysfunction
Hemophilia
DIC
Iatrogenic:
Endoscopic biopsy
CT guided biopsy
Swan Ganz catheterization
Cardiac
Mitral stenosis
left heart failure
Tricuspid endocarditis
Medicines
Aspirin
Anticoagulation
penicillamine
Solvents
Cocaine
Trauma
Thoracic traumas
bronchial rupture
fat embolism
Tracheal-innominate artery
fistula
Other
foreign body
broncho-lithiasis
bronchopleural fistula
Bronchial telangiectasia
amyloidosis
pneumoconiosis
Catamenial hemoptysis Table 1- Conditions causing hemoptysis Diagnosis / Differential Diagnosis Diagnosis / Differential Diagnosis An important step in diagnosis; is to distinguish whether the hemoptysis
is a true hemoptysis or a pseudo hemoptysis. Pseudohemoptysis, that is,
non-pulmonary blood expectoration, is considered as bleeding from the
upper respiratory tract, esophagus, or stomach. Table 2 shows the distinction
between hemoptysis and pseudo hemoptysis. Upper respiratory tract bleeding usually originates from the nose,
nasopharynx, throat, and mouth. In this type of bleeding, inhalations of
bloody secretions cause a cough reflex and may give the impression of
hemoptysis in the form of coughing up blood. Intraoral bleeding is usually
caused by psoriasis of the gums. Here the blood is mixed with saliva. Elif Guliyev Elif Guliyev 23 Since hemoptysis and pseudo hemoptysis are not always easily
differentiated, a detailed history should be taken from all patients and a
careful physical examination should be performed. Table 2- Hemoptysis-pseudo-hemoptysis distinction
Clinical feature
HEMOPTYSIS
PSEUDHEMOPTYSIS
origin of blood
Respiratory tract
Oral cavity, larynx,
esophagus, stomach,
Cough
More often
less often
respiratory symptoms
More often
less often
Esophagogastric symptoms
less often
More often
Alcohol use, liver disease
less often
More often
nausea, vomiting
less often
More often
Hematemesis, melena
less often
More often
The color of expectorated
blood
bright red
brown or black
Intensity of expectoration
clotted or liquid
coffee grounds
Foaminess of expectoration
Generally
rare or absent
pH
alkaline
Acid
alveolar macrophage in
sputum
yes
None
Food particles in the
expectorator
None
Var Table 2- Hemoptysis-pseudo-hemoptysis distinction How much bleeding was in the anamnesis, is the bleeding fresh red,
mixed with sputum, is it the first time or has it happened before, is there
any bleeding from the nose, or gingival, are there signs of infection such as
fever, at night sweats, weight loss, joint pain Do you have signs of chronic
and/or systemic disease such as blood in the urine, rash, smoking, history of
pulmonary, cardiac, renal or rheumatic disease, family or own hematological
disease, history of tuberculosis, use of anticoagulant and antiplatelet drugs
history, cocaine or other substance use, history of deep vein thrombosis
or pulmonary embolism and risk factors, chemical exposure should be
questioned. In the physical examination, signs of respiratory failure such as tachypnea,
cyanosis, and use of accessory respiratory muscles should be evaluated first. Diagnosis / Differential Diagnosis 24 | Hemoptysis 24 | Hemoptysis 24 Hemoptysis Vital signs, condition of the patient, signs of bleeding in the upper respiratory
tract, skin bruising, rash and telangiectasia (hereditary hemorrhagic
telangiectasia or vasculitis, etc.), venous engorgement, peripheral edema,
liver congestion, cachexia, lymphadenomegaly, abnormal heart sounds on
auscultation, wheezing, rales should be examined for localized rhonchi. Diagnostic tests; Diagnostic tests; • Radiological Imaging Radiological Imaging
- Chest X-ray - Computed tomography - Chest X-ray - Computed tomography • Complete blood count, platelet • Complete urine • Renal functions • Looking for ARB • Serological tests • Ventilation perfusion scintigraphy • Echocardiography • Bronchial arteriography • Pulmonary angiography • Bronchoscopy (Fiberoptic, Rigid) Bidirectional chest radiography is the first examination to be requested. Lung X-ray; 33-82% may indicate the localization of bleeding, and 35% may
indicate the underlying cause (tuberculosis or tumor). If the etiology cannot
be identified, contrast-enhanced CT should be performed. Compared to
traditional angiography, it is a more accurate choice if multidetector CT can
distinguish bronchial and non-bronchial systemic arteries more accurately. According to whole blood, coagulation, and inflammation parameters,
routine biochemistry, and patient findings, tests such as d-dimer and
autoantibodies should be requested. In case of insufficient thoracic CT,
bronchoscopy should be performed. If there is no abnormality in CT,
recurrent hemoptysis, or high-risk malignancy is suspected, if there is CT
abnormality, therapeutic bronchoscopy should be performed to stop bleeding
as well as for diagnostic purposes. Rigid bronchoscopy has advantages such
as superior imaging, airway safety, adequate aspiration or cleaning of blood,
clots, and debris, and better use of various therapeutic intervention devices. On the other hand, the fiberoptic bronchoscope is easy to find, can be used
at the bedside, and can be easily applied to the intubated patient. Elif Guliyev | 25 Elif Guliyev | 25 25 Treatment Treatment management in hemoptysis is based on the amount of
bleeding and the vital stability of the patient. Massive hemoptysis is a
medical emergency that needs immediate evaluation and treatment. Death
from hemoptysis is usually due to asphyxia, not blood loss. In addition to
the severity of bleeding, lung reserve also plays a role in hemoptysis to such
an extent that it obstructs the conductive airways of the patient and causes
asphyxia and respiratory failure. Even a small amount of hemoptysis can
cause asphyxia in a patient with chronic lung disease and limited lung reserve. In the first evaluation; Whether there is a life-threatening situation or a
life-threatening situation at any time, comorbidities and treatments that may
be associated with hemoptysis should be evaluated. First things to do in massive hemoptysis; First things to do in massive hemoptysis; 1. To prevent aspiration into the unaffected lung, 2. To stop the bleeding, 3. To treat the disease that causes bleeding. In massive hemorrhages, the cases should be followed up in the intensive
care unit. In order to prevent aspiration into the unaffected lung, the patient
should be laid on his side with the bleeding side down, oxygen support
should be provided, vital parameters should be monitored (saturation, blood
pressure, arterial, etc.), and vascular access should be established. All blood and secretions expected by the patient should be collected in
order to monitor the patient’s vital and hematological findings and determine
the rate of blood and volume lost. Volume loss should be completed and corrected if there is a coagulation
disorder (blood, fresh frozen plasma transfusion, etc.). Medical treatment; -Tranexamic acid (transamine); is a synthetic lysine derivative that inhibits
plasmin activation. Although it does not contribute to clot formation, it
prevents clot disintegration. It is commercially available in 250 mg IV and
250-500 mg oral forms. It is used as 3X1 1 g IV, 3X500 mg orally, and
3X500 mg nebules with 5 cc saline. It is used in hepatic insufficiency, but the
dose should be adjusted in renal insufficiency. -codeine sulfate; 30-60 mg IM every 4-6 hours can be administered to
suppress the cough reflex. 26 | Hemoptysis 26 | Hemoptysis - In cases with high anxiety and agitation, midazolam 2-4 mg iv or 5 mg
diazepam every 6 hours may be useful for sedation. intubation; intubation; If bleeding continues and asphyxia develops; The patient is intubated
with an 8.5 mm or larger tube so that a bronchoscopy can be performed
when necessary. - If the lesion is in the trachea, selective intubation is performed. - While left single-lumen intubation is recommended for right system
bleeding, - In left system bleeding, right single lumen intubation is not
recommended as it will prevent right upper lobe aeration. In cases of left
system bleeding, placement of the endotracheal tube in the trachea and
obstruction of the left main bronchus with a balloon catheter from the outer
part of the endotracheal tube or through the tube in front of the vocal cords
are recommended. bronchoscopy; -Rigid bronchoscopy is preferred. Because with rigid bronchoscopy,
aspiration of blood and clots can be achieved better, it also helps localization
of the bleeding site, the major airways can be seen better and adequate
ventilation can be provided. The disadvantage is that it requires general
anesthesia. -Fiberoptic bronchoscopy, which can be performed at the bedside in
lower grade bleeding, can be selected to evaluate subsegment anatomy and
especially upper lobe orifices. Recently, it has been stated that while the patient is intubated with a
double-lumen endotracheal tube and oxygenation is provided from one
lumen of the tube using fiberoptic bronchoscopy, the bleeding site can be
detected with FOB from the other lumen, and aspiration can be performed
if necessary. This view has not found much support today. If the chest X-ray is normal or if the bleeding side cannot be determined
due to aspiration to the other side, an emergency bronchoscopy can be
performed; 1- The bleeding site is determined 2- The formed coagulum is cleaned 3-Bleeding can be controlled by irrigating the bleeding area with
adrenaline or cold water. 27 Elif Guliyev Elif Guliyev If the blood comes from the right bronchial system, single lung intubation
can be performed on the healthy side with a Fogarty catheter under the
guidance of a bronchoscope. This type of application is not recommended
on the right side as it may obstruct the upper lobe bronchus. Wrong-side
intubation or slippage of the tube can result in death. 26 | Hemoptysis Repetitive bronchial lavage with cold (+40 °C) isotonic liquid,
administered topically with a bronchoscope, can stimulate local
vasoconstriction and accelerate hemostasis. Adrenaline in 1/20.000 dilution
(1 ml adrenaline + 19 ml saline), thrombin, and thrombin/fibrinogen
solutions are also applied topically. When bleeding cannot be stopped with these measures; 1- If the bleeding site is known; When the balloon-buffered catheter
pushed through the bronchoscope with the endobronchial balloon tamponade
method is inflated and fixed in the proximal part of the bleeding segment or
subsegment bronchus, aspiration into the intact lung areas is prevented. The
balloon should be deflated after 24 hours to prevent complications such as
ischemia and post-obstructive pneumonia. 2- If the bleeding site is unknown; Bleeding should be tried to be
controlled by performing unilateral lung ventilation with double-lumen
catheters. In intubated patients with massive hemoptysis, electrocautery, argon
plasma coagulation, and Nd-YAG laser therapy, as well as photo resection
and vaporization, can control bleeding and intervene in the endobronchial
lesion. However, in practice, bleeding can be controlled by irrigation of the
bleeding segment with adrenaline solution or cold water without the need
for many of these methods. The methods used in the treatment of massive
hemoptysis are shown in Table 3. Table 3- Bronchoscopic methods in massive hemoptysis
Topical treatments
Endobronchial treatments
Washing with cold saline (40)
Adrenaline lavage (1:20,000 1-2 ml)
Tranexamic acid
Vasopressin
Ornipressin, Terlipressin
Thrombin-fibrinogen complex
Oxidized regenerated cellulose
Fogarty balloon tamponade
Endobronchial blocker
Silicone plugs
The thermal ablative technique (laser,
APC, Electrocautery, cryotherapy)
Endotracheal intubation Table 3- Bronchoscopic methods in massive hemoptysis 28 | Hemoptysis 28 | Hemoptysis 28 Bronchial Artery Embolization (BAE); It is a minimally invasive and effective method. Especially in hemoptysis
due to bronchial artery bleeding, bronchial artery embolization with
polyvinyl alcohol, particles N-butyl cyanoacrylate glue, gelatin sponges,
triacryl gelatin microspheres, and metallic coils selectively to the bleeding
site is recommended. The full anatomy of the bronchial circulation
should be determined by performing pulmonary angiography before the
procedure. 6.5% spinal artery ischemia is the most important complication. Due to
the recurrence risk of up to 30%; 1- In hemoptysis that cannot be stopped by conventional methods, 2- In those with bilateral disease, 3- It is applied in cases with limited respiratory functions and who cannot
tolerate surgery. Since massive hemoptysis mostly originates from the bronchial arteries,
it is not recommended for bleeding originating from the pulmonary artery. Radiotherapy; -Compression due to edema in the perivascular tissue, -Compression due to edema in the perivascular tissue, - Vascular thrombosis-forming effect is utilized. - Vascular thrombosis-forming effect is utilized. It may be an option when surgical resection is contraindicated and BAE
cannot be performed. It may be particularly useful in hemoptysis caused by
tumors such as pulmonary angiosarcoma or hemangioendothelioma. Surgical; Surgical; Surgical; Indications If the cause of massive hemoptysis is a localized lesion If the cause of massive hemoptysis is a localized lesion • If complete resection is possible • Failure to perform BAE or the continuation of bleeding despite being
performed • If it is thought that it would be a waste of time to try excessive bleeding
and embolization that will disrupt hemodynamics. • These are types of hemoptysis in which embolization is ineffective,
such as pulmonary artery rupture and mycetoma. Elif Guliyev | 29 Elif Guliyev 29 Elif Guliyev Segmentectomy, lobectomy, or pneumonectomy can be performed by
surgical thoracotomy. Up to 50% mortality has been reported in cases
undergoing surgical intervention due to massive hemoptysis. RESOURCES 1- Li H, Ding X, Zhai S, Gao K. A retrospective study on the management of
massive hemoptysis by bronchial artery embolization: risk factors asso-
ciated with recurrence of hemoptysis. BMC Pulm Med. 2023;23(1):87. doi:10.1186/s12890-023-02371-1 2-Carvalho Silva1 M, Filipe Cruz1 J. An undescribed cause of hemopty-
sis. J Bras Pneumol. Published online December 16, 2022:e20220410. doi:10.36416/1806-3756/e20220410 3-McDonaldDM. Angiogenesis and Remodeling of Airway Vasculature in
Chronic Inflammation. Am J Respir Crit Care Med. 2001;164(supple-
ment_2):S39-S45. doi:10.1164/ajrccm.164.supplement_2.2106065 4-Cauldwell EW, Siekert RG. The bronchial arteries; an anatomic study of 150
human cadavers. Surg Gynecol Obstet. 1948 Apr;86(4):395-412. 5-Zheng Z, Zhuang Z, Yang M, et al. Bronchial artery embolization for hemop-
tysis: A systematic review and meta-analysis. Journal of Interventional Me-
dicine. 2021;4(4):172-180. doi:10.1016/j.jimed.2021.08.003 6-Moen CA, Burrell A, Dunning J. Does tranexamic acid stop haemopty-
sis?: Table 1: Interact CardioVasc Thorac Surg. 2013;17(6):991-994. doi:10.1093/icvts/ivt383 7-Prey B, Francis A, Williams J, Krishnadasan B. Evaluation and Treatment of
Massive Hemoptysis. Surgical Clinics of North America. 2022;102(3):465-
481. doi:10.1016/j.suc.2021.11.002 8-Sakr l., Dutau H. Massive hemoptysis: an update on the role of bronchoscopy
in diagnosis and management. Respiration . 2010;80(1):38-58. doi:
10.1159/000274492. Epub 2010 Jan 8. 9-Abdulmalak C, Cottenet J, Beltramo G, Georges M, Camus P, Bonniaud P, Qu-
antin C. Haemoptysis in adults: a 5-year study using the French nationwi-
de hospital administrative database. Eur Respir J 2015 Aug;46(2):503-
11. doi: 0.1183/09031936.00218214. Epub 2015 May 28. 10-Fidan A, Ozdoğan S, Oruç O, Salepci B, Ocal Z, Cağlayan B. Hemoptysis:
a retrospective analysis of 108 cases. Respiratory Medicine 2002; 96(9):
677-680. doi: 10.1053/rmed.2002.1359. 11- Yoon W, Kim JK, Kim YH, Woong T Chung TW, Kang HK. Bronchial
and nonbronchial systemic artery embolization for life-threatening he-
moptysis: a comprehensive review. Radiographics 2002;22:1395. doi:
10.1148/rg.226015180. 30 | Hemoptysis 30 | Hemoptysis | Hemoptysis 30 11-Ittrich H, Bockhorn M, Klose H, Simon M. The Diagnosis and Treatment
of Hemoptysis. Dtsch Arztebl Int 2017; 114:371–81. DOI: 10.3238/
arztebl.2017.0371. 12-Cutshall DM, Inman BL, Myers M. Treatment of Massive Hemoptysis with
Repeated Doses of Nebulized Tranexamic Acid. Cureus. Published online
September 26, 2022. doi:10.7759/cureus.29625 13-Fartoukh M, Voiriot G, Hadad S, et al. Severe haemoptysis. In: Heunks L,
Demoule A, Windisch W, eds. Pulmonary Emergencies. European Respira-
tory Society; 2016:132-150. doi:10.1183/2312508X.10001916 14-Khalil A, Fedida B, Parrot A, Haddad S, Fartoukh M, Carette MF. Severe he-
moptysis: From diagnosis to embolization. Diagnostic and Interventional
Imaging. 2015;96(7-8):775-788. 1
Assit. Prof., Zonguldak Bülent Ecevit University, Faculty of Health Sciences
E-mail: akyol_turkan@hotmail.com, ORCİD ID: 0000-0003-0138-0669 The Effect of Sexual Myths on Quality of Sexual
Life, Marital Satisfaction and Self-Esteem in
Married Women with Physically Disabled Türkan Akyol Güner1 RESOURCES doi:10.1016/j.diii.2015.06.007 15-Rand AD, Blaikley J, Booton R,3 Chaudhuri N, Gupta V, Khalid S, et al. British Thoracic Society guideline for diagnostic flexible bronchoscopy
in adults. Du Rand IA, et al. Thorax 2013;68:i1–i44. doi:10.1136/
thoraxjnl-2013-203618. 16-Davidson K, Shojaee S. Managing Massive Hemoptysis. Chest. 2020
Jan;157(1):77-88. doi: 10.1016/j.chest.2019.07.012. Epub 2019 Jul
30. Chapter 3 1. Introduction Disabled is defined as a person who has lost his physical, mental,
spiritual, emotional, and social abilities in various degrees as a result of any
disease or accident, from birth or later, and cannot fulfill the requirements
of normal life (WHO Global Disability Action Plan 2014–2021; Global
Status Report on Disability and Development Prototype 2015). About
15% of the world’s population and 12.29% of Turkey’s population are
people with disability (Turkey and Disabled People in the World, 2020). Of
these, 8.8% are individuals with physical disabilities and it has been reported
that women have a higher rate of physical disability (Disabled&Elderly,
2017). Physical disability is defined as a disability that does not affect
life functions much (WHO Global Disability Action Plan 2014–2021;
Global Status Report on Disability and Development Prototype 2015). A
physically disabled is a person who has inadequacy, deficiency, and loss of
function in the musculoskeletal system. A significant population is affected
by the problems of people with a physical disability, who are known to
be outnumbered among disability types (Disabled And Elderly Statistics
Bulletin, 2022). People with physical disabilities face many health and social problems
throughout their lives. Although these problems are in various and different
areas, the main problems are related to their married life or sexual life
(Hanson, 1983). The sexual life of the physically disabled is an issue that
is not emphasized much, and there are various sexual myths in societies,
especially about the sexuality of women with disability. False information,
exaggerated beliefs, fabrications, and superstitions that people think are true
about sexual matters are called “sexual myths” (Torun et al., 2011; Keçe,
2019). There are some sexual myths about disabled women that both they
and society believe. These myths; “Disabled women cannot marry, - Disabled
women do not need sex even if they get married, - Disabled women are not
sexually attractive, - Disabled women have excessive sexual desire, - Social
needs of disabled women are more important than sex, - Disabled young
girls do not need sexual education, - Disabled women cannot fully have sex,
- Disabled women should not have children, - Disabled women may not be
able to have sexual intercourse, Disabled women should be grateful in sexual
relations” (Basson, 1998; Mythbusting, 2022). Abstract Physical disability constitutes a large proportion of the population both in
the world and in Turkey. However, the problems related to marriage life,
sexuality and sexual life of this population have not been adequately studied. The aim of this study is to evaluate the effect of sexual myths on the sexual
quality of life, marital satisfaction and self-esteem in married women with
physical disability. This descriptive and cross-sectional study was conducted
between May 2022 - March 2023. The data of the study were collected by
face-to-face interviews with physically disabled married women registered
with the Disabled Associations in Zonguldak. The study was completed
with 266 physically disabled married women who met the inclusion criteria. “Personal Charateristics Form”, “Sexual Myths Scale”, “Sexual Quality of
Life Scale-Female”, “Marital Satisfaction Scale” and “Rosenberg Self-Esteem
Scale” were used for the data collection. SPSS was used to analyze the data. In the study, the level of belief in sexual myths of disabled married women
was found to be above the medium level, and their sexual life quality, marital
satisfaction and self-esteem were found to be low level. In addition, It was
determined that there was a negative and strong relationship between belief
in sexual myths and quality of sexual life (r=-0.71; p<0.001); there was
a negative and moderate relationship between belief in sexual myths and
marital satisfaction (r=-0.51; p<0.05) and self-esteem (r=-0.58; p<0.05). This study showed that married women with disability experience problems
in their sexual lives. It is thought that the data obtained from the study will
contribute to the literature. https://doi.org/10.58830/ozgur.pub128.c509 31 32 | The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... 1. Introduction The state or level of belief in sexual myths, which arise due to many
individual and social factors, varies from person to person with a disability,
and especially women are more affected by this situation. Due to society’s
perspective and pressure on the sexuality of disabled people, women with a 33 Türkan Akyol Güner Türkan Akyol Güner disability believe these sexual myths too much and face many difficulties in
meeting their sexual needs (Torun et al., 2011). However, disabled women
also have rights, sexual feelings, desires, needs, and problems, just like non-
disabled women (Law Students For Reproductive Justice Women With
Disabilities, 2009). In general, this humane need is prejudiced by society
and it is assumed that they cannot have sexual intercourse even if they are
married (Hershey, 2000). This situation negatively affects the sexual life
quality and marital satisfaction of especially married disabled women (Ivy
and Memphis, 2007; Litzinger and Gordon, 2005). Marriage satisfaction is the satisfaction of spouses in their relationships,
happiness in marriage, and positive or negative expression of harmony
between spouses. In other words, marital satisfaction is one of the quality
indicators of marriage and sexuality (Spanier, 1976; Tezer, 1996). It
has also been reported in studies that marital satisfaction affects marital
happiness and support exchange between spouses and is very important
for the successful execution of the marriage process (Ivy and Memphis,
2007; Litzinger and Gordon, 2005; Celenk and Van de Vijver, 2013;
Kudiaki, 2002). In addition, most of the studies have shown that the
sexual quality of life is positively related to marital satisfaction (Ivy and
Memphis, 2007; Litzinger and Gordon, 2005). If physically disabled
women have problems in their sexual life and marital satisfaction, as well
as their already difficult social lives, their sexual worth decreases, and they
may also have to cope with psychological problems such as a lack of self-
confidence and low self-esteem (Earle, 2001; Taleporos and McCabe,
2001). For disabled people, sexual satisfaction and marital satisfaction
can be significant indicators of their social integration, quality of life, and
self-esteem (Lee and Oh, 2012). Self-esteem is the individual’s perception of herself/himself as a
resourceful, valuable person and is considered a positive personality trait. Self-esteem is a function of respect for self and others, confidence, and
self-efficacy (Rosenberg, 1965). It is defined as an individual’s attitude
towards self-importance, competence, and evaluation of achievement
(Coopersmith, 1967). 1. Introduction Accordingly, self-esteem, which is the sum of an
individual’s positive and negative attitudes towards herself/himself, is the
combination of competence, personal worth, and body image. The feelings
of both inadequacy and frustration in disabled people affect their self-esteem
(Kassinove and Tafrate, 2002; Yatkın, 2013). The individual’s realization of
his/her worth and having positive feelings towards himself/herself can be
considered an important indicator of mental health. Low self-esteem can
cause many problems related to sexuality, especially sexual interest/arousal The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... 34 disorder. Communication problems between spouses can cause feelings of
insignificance, low libido, and sexual dissatisfaction. Self-esteem and self-
confidence of disabled people increase in direct proportion to satisfaction
with sexual life (Earle, 2001). Information on disability and sexuality in
the literature is also scarce and limited. It has been reported that studies
should be carried out on these issues to reveal the problems experienced by
disabled individuals in their sexual lives and to find solutions. In addition,
sexual myths are among the important factors that can affect the general
public health, as they affect the sexual process and the sexual quality of life
(Taleporos and McCabe, 2001; Wiegerink et al., 2006; Cumurcu et al.,
2012). In the literature review, no study was found that evaluated the effects
of sexual myths on the sexual quality of life, marital satisfaction, and self-
esteem in married women with disability. The aims of this study were: The aims of this study were: 1. To determine the effect of sexual myths on the sexual quality of life in
married women with physical disabilities. 2. To determine the effect of sexual myths on marital satisfaction in
married women with physical disabilities. 3. To determine the effect of sexual myths on self-esteem in married
women with physical disabilities. 4. To determine the sociodemographic factors affecting sexual myth,
sexual quality of life, marital satisfaction, and self-esteem in physically
disabled married women. 2.2. Data Collection Process “Personal Characteristics Form”, “Sexual Myths Scale”, “Sexual Quality
of Life Scale-Female”, “Marital Satisfaction Scale” and “Rosenberg Self-
Esteem Scale” were used for the data collection. 2.2.1. Personal Characteristics Form The form consisted of eight questions prepared by the researcher by
examining the literatüre (Litzinger and Gordon, 2005; Celenk and Van de
Vijver, 2013; Taleporos and McCabe, 2001). This form included questions
about the personal characteristics, disability, and sexual lives of disabled
women. 2.2.2. The Sexual Myths Scale (SMS) This scale was developed to determine whether individuals have sexual
myths or not by Gölbasi et al. (Golbasi et al., 2016). The scale has a total
of 28 items under eight sub‐scales. The scale is a 5‐point Likert‐type scale,
which is scored from 1 to 5. Total scores range from 28 to 140, where
higher scores indicate an increase in the likelihood of having a sexual myth. Cronbach alpha of the scale was found to be 0.91. In this study, Cronbach’s
alpha was determined to be 0.90. 2.1. Design and Participants This descriptive and cross-sectional study was conducted with physically
disabled married women living in Zonguldak between May 2022 - March
2023. Zonguldak province is the 21st province with the highest number
of the disabled population in Turkey. The data of the study were collected
through face-to-face interviews with physically disabled married women
registered with the three Disability Associations in Zonguldak. The study’s
universe consists of 301 physically disabled married women who were
members of associations. The sample of the study was determined as 170
women from the study population with a 95% confidence interval and a
5% margin of error. OpenEpi, Version 3 program was used for sample
calculation (http://www.openepi.com). The purposive sampling method 35 Türkan Akyol Güner | Türkan Akyol Güner was used to reach sampling in the study. The study was completed with 266
physically disabled married women who met the inclusion criteria. Between
the ages of 18 and 65, married, a woman, physically disabled, literate, and
willing to participate in the study were the inclusion criteria. 2.2.3. Sexual Quality of Life-Female (SQOL-F) The sexual quality of life of women was measured using the Turkish
version (Tuğut and Gölbaşı, 2010). of the SQOL-F, which was developed by
Symonds et al. (Symonds et al., 2005). The sexual quality of life of women
for the past 4 weeks was investigated using this scale, which can be used as
a valid and reliable measurement tool for women aged 18-65. For the scale,
consisting of 18 items, the scores of items 1, 5, 9, 13, and 18 were reversed
before calculating the scale items, which were scored between 1 and 6. The
total score to be obtained from the scale was converted to 100. The formula
[(raw score of the scale - 18) x 100/90] was used for this conversion. High
scores indicate a good sexual quality of life (Tuğut and Gölbaşı, 2010). Cronbach’s alpha value of the Turkish version of the scale was 0.83. In this
study, Cronbach’s alpha value of the scale was 0.82.” 36 | The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... 2.2.4. Marriage Life Scale (MLS) The scale was developed by Tezer (1996) to measure the general
satisfaction level of spouses regarding their marital relationship. The scale is
composed of 10 items. The participants assessed to what extent each item
defined them, by using a 5-point Likert scale (1 = I do not agree, 5 = I
agree). The highest point on the scale is 50, and the lowest point is 10. A
high score on the scale indicates a high level of marital satisfaction. The
Cronbach Alpha coefficient of the scale was 0.91. In this study, Cronbach’s
alpha value of the scale was 0.89 (Tezer, 1996). 2.3. Statistical analysis Statistical analysis of the data was performed using SPSS 22.0 (IBM
Corporation, Armonk, NY, USA) package program. The conformity of the
data to the normal distribution was assessed with Kolmogorov-Smirnov
and Shapiro-Wilk tests. Percentage, mean±SD, t-test, One-Way Analysis of
Variance (ANOVA), Kruskall Wallis H Test, Mann Whitney U, and Tukey
test were used in data analysis. Pearson Moments Multiplication Correlation
analyses were used to evaluate the relationship between variables. In the
calculation of the correlation strength, the following ranges were taken
as a reference: very weak correlation (r = 0–0.25), weak correlation (r =
0.26–0.49), moderate correlation (r = 0.50–0.69), strong correlation (r =
0.70–0.89), and very strong correlation (r = 0.90–1.0) (Gürbüz & Şahin,
2014). p <0.05 value was considered to be significant. 2.2.5. Rosenberg Self-Esteem Scale (RSES) The scale developed by Rosenberg (1965) has 12 subdimensions. In
this study, the Self-Esteem sub-dimension (10 items) was used (Rosenberg,
1965). It was adapted into Turkish by Çuhadaroğlu in 1986 (Çuhandaroğlu,
1986). The score that can be obtained from the scale ranges from “0” to “6”. High scores indicate low self-esteem. The Cronbach Alpha coefficient of the
scale was 0.75. In this study, Cronbach’s alpha value of the scale was 0.78. 2.4. Ethical standards This study was performed in line with the principles of the Declaration
of Helsinki. Ethical approval was obtained from the Zonguldak Bülent
Ecevit University Human Researches Ethics Commission (Date/Number:
13.05.2022-165693). Then, permission was obtained from the Zonguldak
Branch Office of the Turkish Disabled Association for disabled associations
where the study was conducted (E-46751649- E-2180878-105754). The 37 Türkan Akyol Güner | Türkan Akyol Güner participants were informed about the purpose and benefits of the study and
were asked to sign the “Informed Consent” form. Permission for the use of
the scales was obtained from the responsible authors via e-mail. 3. Results The descriptive characteristics of married women with physical disabled
were given in Table 1. Accordingly, 42.9% were in the 31-40 age range, 49.6%
were married between 6-10 years, 66.2% were primary school graduates,
46.6% had one child, 78.2% were unemployed, and the majority of them
had moderate income conditions. 49.6% of disabled women had sexual
intercourse 1 time per month or less and 74.4% were congenitally disabled. Table 1. Descriptive characteristics of married women with a physical disabled (N=266)
Variables
n(%)
Age
20-30 years
90 (33.8)
31-40 years
114 (42.9)
41 and above
62 (23.3)
Duration of marriage
1-5 year
62 (23.3)
6-10 year
132 (49.6)
11 and above
72 (27.1)
Education status
Primary education
176 (66.2)
High school
52 (19.5)
Undergraduate
38 (14.3)
Number of children
0 child
62 (23.3)
1 child
124 (46.6)
2 and above child
80 (30.1)
Working status
Yes
58 (21.8)
No
208 (78.2)
Income status
Good
38 (14.3)
Middle/Poor
228 (85.7)
Frequency of sexual intercourse
1-2 times a week
92 (34.6)
3 times or more a week
42 (15.8)
1 time per month or less
132 (49.6)
Disability status
Congenital
198 (74.4)
Later
68 (25.6) Table 1. Descriptive characteristics of married women with a physical disabled (N=266)
Variables
n(%) Table 1. Descriptive characteristics of married women with a physical disabled (N=266) 38 | The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... The scales mean scores of the disabled married women were given in Table
2. According to the scale evaluation, it was determined that the level of belief
in sexual myths of disabled married women was above the moderate level
(88.56±19.61). Moreover, their sexual life quality (46.28±5.12), marital
satisfaction (26.26±12.47), and self-esteem (3.20±1.64) were found to be
low levels. Table 2. Mean scores of scales
Mean±SD
Min-Max
88.56±19.61
28-120
46.28±5.12
21-100
26.26±12.47
10-50
3.20±1.64
0-6
SMS: Sexual Myths Scale; MLS: Marital Life Scale
SQOL-F: Sexual Quality of Life Questionnaire-Female
RSES: Rosenberg Self-Esteem Scale Table 2. Mean scores of scales The comparison of the mean scores of the scales according to the
descriptive characteristics of the physically disabled married women was
given in Table 3. A statistically significant difference was found between the
mean SMS scores of disabled women according to age (p=0.012), education
status (p=0.001), working status (p=0.003), income status (p=0.017), and
frequency of sexual intercourse (p=0.047). 3. Results It was determined that the level
of belief in sexual myths was higher among disabled women who were over
41 years old, graduated from primary school, did not work, had a medium
or low income, and had sexual intercourse once a month or less (Table 3). A statistically significant difference was found between the mean SQLQ-F
scale scores of disabled married women according to age (p=0.041),
duration of marriage (p=0.020), education status (p=0.036), frequency of
sexual intercourse (p=0.045) and disability status (p=0.047). According
to this; It was determined that the sexual quality of life was higher and
statistically significant for those between the ages of 20-30, those with a
marriage duration of 1-5 years, those with an undergraduate degree, those
who had sexual intercourse 1-2 times a week, and those with congenital
disability (Table 3). A statistically significant difference was found between the mean MLS
scores of disabled women according to age (p=0.007), education status
(p=0.041), income status (p=0.031), frequency of sexual intercourse
(p=0.027), and disability status (p=0.041). It was determined that 39 Türkan Akyol Güner | 39 Türkan Akyol Güner the marital satisfaction of disabled women between 20-30 years of age,
undergraduate graduates, good income, having sexual intercourse 1-2 times
a week, and later having a disability were higher and more significant. When
the mean scores of the RSES were examined, it was determined that the
self-esteem of disabled women was lower and more significant as their
age increased, educational status, income status, and frequency of sexual
intercourse decreased (Table 3). Table 3. Mean scores of scales according to descriptive characteristics of women with a
physical disabled Table 3. 3. Results Mean scores of scales according to descriptive characteristics of women with a
physical disabled
SMS
SQOL-F
MLS
RSES
Mean±SD
Mean±SD
Mean±SD
Mean±SD
Age
20-30 years1
72.11±8.27
46.97±11.17
28.28±2.75
2.41±1.48
31-40 years2
80.07±7.93
43.70±12.35
26.52±3.48
3.06±1.45
41 and above3
88.67±11.02
40.05±7.89
25.61±4.18
3.58±1.87
Statistics
F=18.422;
p=0.012; 3>1*
F=3.567;
p=0.041; 1>3*
F=10.217;
p=0.007; 1>3*
KW=10.624;
p=0.003; 1>3*
Duration of marriage
1-5 years1
84.61±4.79
49.97±3.28
27.62±5.28
3.21±1.85
6-10 year2
86.05±6.92
47.01±6.07
26.12±6.92
3.22±1.67
11 and above3
84.17±5.34
45.87±5.01
25.37±6.08
3.20±1.08
Statistics
F=5.791;
P=0.736
F=4.110
p=0.020; 1>3*
F=4.927;
p=0.131
KW=10.145;
p=0.101
Education status
Primary education1
93.01±8.40
41.97±13.41
24.48±7.03
3.37±1.87
High school2
86.52±7.38
46.85±12.95
26.57±6.12
3.04±1.84
Undergraduate3
62.90±9.25
48.10±11.96
27.91±9.01
2.91±1.24
Statistics
F=23.812;
P=0.001; 1>3*
F=3.958;
p=0.036; 3>1*
F=2.980;
p=0.041; 3>1*
KW=10.627;
p=0.040; 3>1*
Number of children
0 child1
84.27±9.01
46.04±11.14
25.98±4.61
3.12±1.65
1 child2
85.58±5.92
45.57±10.05
22.57±3.80
3.23±1.91
2 and above child3
85.97±8.12
45.92±15.45
21.93±3.92
3.21±1.54
Statistics
F=4.928;
p=0.692
F=0.617;
p=0.541
F=4.845;
p=0.057
KW=4.453;
P=0.384
Working status
Yes
80.01±4.18
45.03±13.76
26.91±6.01
2.66±1.30
No
88.12±6.57
45.43±8.57
26.20±5.87
3.47±1.64
Statistics
t=0.129;
p=0.003
t=1.627;
p=0.523
t=0.191;
p=0.071
U=103.52;
p=0.021
Income status
Good
81.71±1.62
46.06±14.01
26.78±5.58
2.84±1.15
Middle/Poor
87.30±3.58
44.65±13.01
23.18±6.21
3.45±1.58 40 | The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... 40 | The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... 40 | The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... 40 Statistics
t=0.189;
p=0.017
t=1.629;
p=0.601
t=1.017;
p=0.031
U=104.50;
p=0.021
Frequency of sexual
intercourse
1-2 times a week1
82.17±7.28
46.03±14.14
28.12±11.78
2.34±1.45
3 times a week or more2 86.21±5.32
44.65±13.09
26.01±9.78
2.74±1.56
1 time per month or
less3
87.98±4.27
40.04±12.78
23.47±5.31
3.37±1.45
Statistics
F=10.272;
p=0.047; 3>1*
F=5.758;
p=0.045;1>3
F=3.928;
p=0.027; 1>3*
KW =9.324;
p=0.004;
1>3*
Disability status
Congenital
84.01±5.11
46.06±8.10
22.87±3.12
3.29±1.65
Later
83.21±4.75
43.35±6.84
25.78±2.85
3.02±1.67
Statistics
t=1.042;
p=0.103
t=1.871;
p=0.047
t=1.875;
p=0.041
U=-92.12;
p=0.007
t=Independent Sample t-test; F: ANOVA; KW: Kruskal Wallis H test U: Mann Whitney U test,
*: Tukey test
SMS: Sexual Myths Scale; SQOL-F: Sexual Quality of Life Questionnaire-Female; MLS: Marital
Life Scale
RSES: Rosenberg Self-Esteem Scale In Table 4, the correlation between the level of belief in sexual myths,
quality of sexual life, marital satisfaction, and self-esteem of physically
disabled married women was examined. 3. Results Accordingly, there was a negative
and strong correlation between the level of belief in sexual myths and the
quality of sexual life(r=-0.71; p<0.001); It was determined that there was
a negative and moderate relationship between belief in sexual myths and
marital satisfaction (r=-0.51; p<0.05) and self-esteem (r=-0.58; p<0.05). It was determined that there was a moderate and positive correlation between
the quality of sexual life and marital satisfaction (r=0.62; p<0.001) and self-
esteem (r=0.50; p<0.05), and a moderate and positive correlation between
marital satisfaction and self-esteem (r=0.63; p<0.001). Table 4. The relationship between sexual myths, quality of sexual life, marital
satisfaction and self-esteem in women with physical disabled Table 4. The relationship between sexual myths, quality of sexual life, marital
satisfaction and self-esteem in women with physical disabled
SMS
SQOL-F
MLS
RSES
SMS
1.00
SQOL-F
-0.71**
1.00
MLS
-0.51*
0.62**
1.00
RSES
-0.58*
0.50*
0.63**
1.00
Pearson Moments Multiplication Correlation
*p<0.05
**p<0.001
SMS: Sexual Myths Scale; SQOL-F: Sexual Quality of Life Questionnaire Female
MLS: Marital Life Scale; RSES: Rosenberg Self-Esteem Scale y
y
MLS: Marital Life Scale; RSES: Rosenberg Self-Esteem Scale Türkan Akyol Güner | 41 41 The regression table shows the effects on sexual myths of sexual
quality of life, marital satisfaction, and self-esteem in physically disabled
married women (Table 5). According to this; Sexual quality of life, marital
satisfaction, and self-esteem were determined to be effective factors in sexual
myths (F=30.994; p=0.000). These results are also consistent with the
correlation analysis results. Table 5. Regression table of the effects on sexual myths of sexual quality of life, marital
satisfaction, and self-esteem
Dependent
Variable
Independent
Variable
β
t
p
Adj. R2
F
Constant
8.748
0.000*
0.499
30.994
Sexual Myths
Sexual Quality of Life -0.453
-6.476
0.000*
Marital Satisfaction
-0.378
-5.855
0.018**
Self-Esteem
-0.320
-4.980
0.026**
*p<0.001;
**p<0.05
R=Regression coefficient Table 5. Regression table of the effects on sexual myths of sexual quality of life, marital
satisfaction, and self-esteem 4. Discussion Physical disability constitutes a large proportion of the population both
in the world and in Turkey. However, the problems related to married life,
sexuality, and sexual life of this population have not been adequately studied. Considering the importance of the subject for disabled individuals, it has
been reported that it is important to conduct new studies to find solutions
to the problems (Taleporos and McCabe , 2001; Wiegerink et al., 2006). This study, which was planned for these reasons, it was aimed to evaluate the
effect of sexual myths on the sexual quality of life, marital satisfaction, and
self-esteem in physically disabled married women. The reason why married
women were chosen as a criterion in the study is that false beliefs about sexuality
are more common in women and they need more sexual health information. This
situation has more negative effects on marital satisfaction and self-esteem (Basson,
1998; Hershey, 2000; Taleporos and McCabe, 2001). Sex myths, which are one of the issues that affect sexuality and sexual
satisfaction, cause sexuality to be complicated. The most important reasons
for the emergence of sexual myths are the inability to talk about sexuality, the
value judgments of society, and the insufficient number of scientific studies on
sexuality (Mythbusting, 2022; Taleporos and McCabe, 2001). In the study,
it was determined that the physically disabled married women had a belief in
sexual myths above the moderate level according to the scale evaluation. In 42 | 42 The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... a study conducted with disabled individuals, it was determined that disabled
women were more exposed to sexual myths and this reduced their sexual
quality of life (McKenzie, 2012). In similar studies, it was determined that
disabled people had sexual myths and this situation reduced their sexual life
satisfaction (Taleporos and McCabe, 2001; Wiegerink et al., 2006). In the
study, it was observed that the level of belief in sexual myths was higher in
those who were older, less educated, unemployed, low-income, and had less
sexual intercourse. As a result of a study conducted by Taleporos and McCabe
on the sexual lives of people with a physical disability, it was determined that
age, educational status, and frequency of sexual intercourse affect the level of
belief in sexual myths (Taleporos and McCabe, 2001). There have not been
many studies on sexual myths in people with disability. 4. Discussion This situation limits
the discussion of the study results. However, the results of the study were
found to be similar to the results of the literature. Sexuality constitutes an important dimension of the quality of life for
people (Earle, 2001). People with physical disabilities struggle with many
sexual problems related to their physical limitations. This situation causes
a decrease in the sexual quality of life in people with disability (Taleporos
and McCabe, 2001). In the study, when the sexual quality of life of married
women with a physical disability was examined, it was determined that it
was at a low level according to the scale evaluation. As a result of a study
conducted on the sexual quality of life of disabled individuals by Wiegerink
et al., it was reported that the sexual quality of life of disabled people was
low (Wiegerink et al., 2006). In similar studies, it has been reported that
disabled individuals experience some difficulties in sexual relations and
their sexual quality of life was low (Earle, 2001; Taleporos and McCabe,
2001; Glass and Soni, 1999). These results are similar to the results of the
study. Different from the results of this study, some studies showed that
disabled women had a normal sexual life like their same sex and did not
experience great difficulties and that physically disabled women got used to
sexual life more easily. Disabled women were reported to have higher sexual
satisfaction, higher sexual esteem, and lower levels of sexual depression than
men. It was stated that this was because women paid less attention to their
genital functions (Drench, 1992; Tepper et al., 2001; Silvers, 1996). In the study, it was determined that age, duration of the marriage,
educational status, frequency of sexual intercourse, and disability status
affect the sexual quality of life in disabled women. In the study, the sexual
quality of life of women with a congenital physical disability was found to be
higher. It has been reported that people with long-term physical disabilities
experience more positive feelings about their sexuality over time (McCabe 43 Türkan Akyol Güner and Taleporos, 2003). This situation can be interpreted as the sexual
adaptation process of women with a physical disability getting better as they
get used to and accept their disability. 4. Discussion As a result of a study examining the
sexual quality of life of disabled people, it was seen that the duration of the
marriage and educational status affect the quality of sexual life, similar to this
study’s results (Taleporos and McCabe, 2002). When each individual reaches a certain maturity, society expects her/him
to marry, establish a family and have children. However, when it comes
to the marriage of disabled people, it is strange for them to get married. It is thought that disabled women cannot be good wife, a good mothers,
cannot fulfill their domestic responsibilities, and have no sex life. Marriage
and family life of disabled people is an issue that is not emphasized. When
the literature is examined, it has been seen that the studies on the marriages
and marital satisfaction of disabled individuals are very limited and it is
recommended to conduct similar studies (Orbuch et al., 1996). In addition,
there is no study in the literature examining the marital satisfaction of
disabled people according to different variables. The results of this study
are therefore important. Studies have mainly focused on families with
disabled children and parents. It was found that married women with a
physical disability who participated in this study had a low level of marital
satisfaction. In addition, it was determined that age, education level, income
status, frequency of sexual intercourse, and disability status affect marital
satisfaction. In similar studies, it was determined that people with physical
disabilities had low marital satisfaction (Lee and Oh, 2012). In addition,
similar to the results of the study, it was determined that age, education level,
income status, and sexual satisfaction affect marital satisfaction in physically
disabled people (Orbuch et al., 1996; Bradbury et al., 2000; Fincham and
Beach, 2010). It is stated that being disabled from birth is an important factor in
reducing marital satisfaction in disabled people (Lobentanz et al., 2004). In
the study, it was determined that the marital satisfaction of disabled women
whose disability occurred later was higher. As a result of a study conducted
on 1217 disabled married people in the United States, it was determined that
the subsequent occurrence of physical disability increases marital satisfaction
(Yorgason et al., 2008). In the results of similar studies, it was reported that
congenital physical disability reduces marital satisfaction (Lobentanz et al.,
2004; Nosek et al., 1985). 4. Discussion Self-esteem, which is the sum of an individual’s positive and negative
attitudes towards herself/himself, is the combination of social competence, The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... 44 personal worth, and body image. The feeling of frustration and labeling
in disabled people affect self-esteem (Rosenberg, 1965; Yatkın, 2013). In
addition, organ deficiency is thought to have a significant effect on leading
to low self-esteem. In the study, it was determined that the self-esteem of
married women with a physical disabilities was low. Similar to the results
of the study, in a study conducted with physically disabled people, it was
determined that the self-esteem of disabled people was lower than that of
non-disabled people (Franzoı et al., 1989). In the study, it was observed
that age, education level, income status, employment status, and frequency
of sexual intercourse affected the self-esteem of disabled women. In similar
studies, it was determined that self-esteem was higher in disabled people
with high educational and economic status and working (Akpınar and
Şahin, 2016; Dökmen and Kışlak, 2004). It can be thought that economic
comfort, having a job and social security increase social status, and increase
self-esteem by making individuals feel more comfortable and safe. Disabled people struggle with many sexual problems related to the
physical limitations they experience. These situations can cause a decrease
in sexual relations and sexual worthiness in disabled people (Taleporos and
McCabe, 2001). In the study, it was determined that there was a significant
relationship between the frequency of sexual intercourse and self-esteem,
and it was determined that those who had more frequent sexual intercourse
had higher self-esteem. In a similar study, it was seen that the frequency of
sexual intercourse and sexual life satisfaction were directly proportional to
self-esteem (Earle, 2001). According to the study results; No statistically significant difference was
found between self-esteem and disability status. Similarly, in the study of
Balcı and Şahin, no significant difference was found between self-esteem and
disability status (Balcı and Şahin, 2016). In Yatkın’s study, it was observed
that being physically disabled, whether congenital or later, did not affect
self-esteem (Yatkın, 2013). These results are similar to this study’s results. Implications To prevent the sexual problems of disabled people; Awareness should
be created by planning education on this issue in society; Educated people
should be trained to provide professional counseling to the families of disabled
people on sexual issues; Health professionals should also be provided with
in-service training on sexual problems and coping strategies for the disabled
people. It is recommended to carry out studies involving large groups to
understand what types of sexual problems are experienced according to the
type of physical disability. Limitations The lack of studies on sexual difficulties and marital relationships among
disabled persons limited the discussion of the study’s findings. Another
weakness of the study is that this study group is special, the number of
married women with disabilities registered with the disabled association is
low, and the total population does not participate. 5. Conclusion People with a physical disability may experience numerous difficulties in
their sexual lives as in other areas. Experiencing sexual problems in addition
to physical problems can cause problems in psychosocial life and marital
relations. Identifying sexual problems in people with physical disabilities
determines how we can help them. This is important that increase the
quality of life of disabled people. It should not be forgotten that people
with disability are as normal as people who do not have regular sexual life Türkan Akyol Güner | 4 Türkan Akyol Güner | Türkan Akyol Güner 45 and have children, and they should be supported. The data obtained from
this study will make it possible to evaluate the marriages of married disabled
women and will provide new information on marriage and sexual problems. It is thought that this information will be a source for education programs
on disability and sexuality and will guide experts working in this field. Acknowledgments I’d want to thank the disabled women and the presidents of the
associations where the survey was performed for their help. Disclosure statement Disclosure statement The author have no competing interest to disclose. Funding This study is not supported by any funding. | The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... 46 References Akpınar, R.B., & Şahin, G. (2016). Anger and Anger Expression Styles, Sel-
f-Esteem and Life Satisfaction of Individuals with Orthopedic Handicap. Journal of Nursology, 19, 0-0. doi.org/10.17049/ahsbd.38376 Basson, R. (1998). Sexual health of women with disabilities. Canadian Medical
Association Journal. 159(4), 359-362. Bradbury, T., Fincham, F.D., & Beach, S.R.H. (2004). Research on the nature and
determinants of marital satisfaction: A decade in review. Journal of Marriage
and Family, 62(4), 964–980. doi.org/10.1111/j.1741-3737.2000.00964.x Celenk, O., & Van de Vijver, F.J. (2013). What makes couples hap-
py? Marital and life satisfaction among ethnic groups in the Net-
herlands. Journal of Cross-Cultural Psychology. 44(8), 1273-1291. doi:10.1177/0022022113486003 Coopersmith, S. (1967). The Antecedents of self-esteem. Published by W. H. Freeman and Co Ltd, New York. Cumurcu, B., Karlıdağ, R., & Almış, B.H. (2012). Sexuality in the physically
disabled. Current Approaches in Psychiatry, 4(1), 84-98. Çuhandaroğlu, F. (1986). Self-esteem in adolescents. Unpublished Specializa-
tion Thesis. Hacettepe University Faculty of Medicine, Department of
Psychiatry, Ankara. Disability - Draft WHO global disability action plan 2014–2021: Better health
for all people with disability - Report by the Secretariat. Sixty-Seventh World
Health Assembly, A67/16; 2014. http://www.who. int/disabilities/action
plan/en Disabled and elderly statistics bulletin. (2022). https://aile.gov.tr/media/129311/
eyhgm_istatistik_bulteni_kasim_22.pdf. Disabled&Elderly services, family and social policies ministry of Turkey. (2017). http://www.gsdrc.org/wpcontent/uploads/2017/09/179-Disability-pre-
valence-and-trends.pdf Dökmen, Z.Y., & Kışlak, Ş.T. (2004). Comparision of Handicapped and Non-
handicapped University Students’ Demographical and Psychological
Characteristics and Problems. Kriz Dergisi, 12, 33-47. doi.org/10.1501/
Kriz_0000000207 Drench, M. (1992). Impact of altered sexuality and sexual function in spinal
cord injury: A review. Sexuality and Disability, 10, 3-14. doi.org/10.1007/
BF01102244 Earle, S. (2001). Disability, facilitated sex and the role of the nurse. Journal of Ad-
vanced Nursing. 36(3), 433-440. doi:10.1046/j.1365-2648.2001.01991.x Fincham, F.D., & Beach, S.R.H. (2010). Marriage in the new millennium: A
decade in review. Journal of Marriage and Family, 72(3), 630–649. doi. org/10.1111/j.1741-3737.2010.00722.x Türkan Akyol Güner 47 Franzoı, S.L., Kessenıch, J.J., & Sugrue, P.A. (1989). Gender diffrences in the
experience of body awareness. An experimental sampling study. Sex Roles,
21, 499-515. doi.org/10.1007/BF00289100 Glass, C., & Soni, B. (1999). Toolbox: Sexual problems of disabled patients. The Western Journal of Medicine, 171, 107-109. Global Status Report on Disability and Development Prototype. (2015). http://
www.un.org/esa/socdev/documents/disability/2016/GlobalStatusRepor-
tonDisabilityandDevelopment.pdf Golbasi, Z., Evcili, F., Eroglu, K., & Bircan, H. (2016). Sexual Myths Scale
(SMS): development, validity and reliability in Turkey. Sexuality and Di-
sability, 34(1), 75‐87. Gürbüz, S., & Şahin, F. (2014). Research methods in social sciences. References Seçkin Pub-
lishing, Turkey, 100-130. Hanson, L. (1983). Designing with care: A guide to the adaptation of the built
environment for disabled persons. New York, United Nations. Hershey, L. (2000). Women with disabilities: health, reproduction, and sexua-
lity. Global women’s ıssues and knowledge, pp. 58-80. Routledge Press. Ivy, A.U., & Memphis, U.S. (2007). The influence of a surrender style of coping
and empathy on marital and sexual satisfaction. Dissertation Abstracts In-
ternational. 67 (9-B), 5407. Kassinove, H., & Tafrate, R.C. (2002). Anger management: The complete tre-
atment guidebook for practitioners. pp. 270-271. California: Impact
Publishers. Keçe, C. (2019). Bed legends (3rd Edition), Yagci S (Ed), pp. 11-20. Compass
publishing, Ankara. Kudiaki, Ç. (2002). The relationship between sexual satisfaction and marital
adjustment (Unpublished Master’s Thesis). Ankara University, Ankara. Law students for reproductive justice women with disabilities. (2009). http://
lsrj.org/documents/09_Women_with_Disabilities.pdf. Lee, E-K.O., & Oh, H. (2012). Marital satisfaction among adults with disabi-
lities in South Korea. Journal of Disability Policy Studies. 23(4), 215–224. doi.org/10.1177/104420731246766 Litzinger, S., & Gordon, K.C. (2005). Exploring relationships among commu-
nication, sexual satisfaction and marital satisfaction. Journal of Sex &Ma-
rital Therapy. 31, 409-424. Lobentanz, I.S., Asenbaum, S., Vass, K., Sauter, C., Klösch, G., Kolleg-
ger, H., & Zeitlhofer, J. (2004). Factors influencing quality of life in
multiple sclerosis patients: Disability, depressive mood, fatigue and
sleep quality. Acta Neurologica Scandinavica, 110 (1), 6–13. doi. org/10.1111/j.1600-0404.2004.00257.x 48 | The Effect of Sexual Myths on Quality of Sexual Life, Marital Satisfaction and Self-Esteem... 48 McCabe, M.P., & Taleporos, G. (2003). Sexual esteem, sexual satisfaction, and
sexual behavior among people with physical disability. Archives of Sexual
Behavior, 32(4), 359-369. doi: 10.1023/a:1024047100251. McKenzie, J.A. (2013). Disabled people in rural South Africa talk about sexua-
lity. Culture, Health & Sexuality, 1–15. Mythbusting. (2022). http://www.sexualityanddisability.org/sexuality/myth-
busting.aspx Nosek, M.A., Fuhrer, M.J., & Potter, C. (1995). Life satisfaction of peop-
le with physical disabilities: Relationship to personal assistance, disa-
bility status, and handicap. Rehabilitation Psychology, 40(3), 191–202. doi: 10.1037/0090-5550.40.3.191 Orbuch, T.L., House, J.S., Mero, R.P., & Webster, P.S. (1996). Marital quality
over the life course. Social Psychology Quarterly, 59 (2), 162–171. doi. org/10.2307/2787050 Rosenberg, M. (1965). Society and the adolescent self image. Princeton Uni-
versity Press. Silvers, B. (1996). Sexuality, early-onset physical disability, and sense of cohe-
rence (Doctoral dissertation). Alameda, California School of Professional
Psychology. Spanier, G.B. (1976). The measurement of marital quality. Journal of Sex &Ma-
rital Therapy. 5, 288– 300. doi: 10.1080/00926237908403734. 1
Assoc. Prof., Van Yüzüncü Yıl University, sadielasan@yyu.edu.tr, 0000-0002-3149-6462
2
Teacher, Repuclic of Türkiye Ministry of National Education, Van Fevzi Geyik Primary
School, kayramyagizz@gmail.com References Symonds, T., Boolell, M., & Quirk, F. (2005). Development of questionnaire on
sexual quality of life in women. Journal of Sex & Marital Therapy, 31(5),
385-397. Taleporos, G., & McCabe, M. (2002). The impact of sexual esteem, body es-
teem, and sexual satisfaction on psychological well-being in people
with physical disability. Sexuality and Disability, 20(3), 176–183. doi. org/10.1023/A:1021493615456 Taleporos, G., & McCabe, M.P. (2001). Physical disability and sexual esteem. Sexu-
ality and Disability. 19, 131-148. doi.org/10.1023/A:1010677823338 Tepper, M.S., Whipple, B., Richards, E., & Komisaruk, B.R. (2001). Women
with complete spinal cord injury: A phenomenological study of sexual
experiences. Journal of Sex & Marital Therapy, 27, 615-623. Tezer, E. (1996). Conflict-handling behavior toward spouses and supervisors. The Journal of Psychology. 130, 281-292. doi.org/10.1080/00223980.199
6.9915009 Tezer, E. (1996). Satisfaction from marital relationship: Marital life scale. Tur-
kish Psychological Counseling and Guidance Association, 2, 1–7. Retrieved
from https://dergipark.org.tr/tr/pub/tpdrd/issue/21427/229707 Türkan Akyol Güner | 4 49 Türkan Akyol Güner Torun, F., Torun, S.D., & Özaydın, A.N. (2011). Men’s belief in sexual myths
and factors effecting these myths. Düşünen Adam The Journal of Psychiatry
And Neurological Sciences. 24, 24-31. doi: 10.5350/DAJPN2011240103 Tuğut, N., & Gölbaşı, Z. (2010). A validity and reliability study of Turkish
version of the Sexual Quality of Life Questionnaire-Female. Cumhuriyet
Medical Journal, 32, 172-180. Turkey and in the world disabled people. (2020). https://ey-der.com/ana-say-
fa/turkiyevedunyadaengelliler/#:∼:text=Bu%20nedenle%2C%20d%-
C3%BCnyadaki%20%E2%80%9Cen%20b%C3%BCy%C3%BCk,siy-
se%2050% 2D64%20ya%C5%9F%20aras%C4%B1nda%E2%80%A6. Wiegerink, D.J., Roebroeck, M.E., Donkervoort, M., Stam, H.J., & Cohen-Ket-
tenis, P.T. (2006). Social and sexual relationships and young adults with
cerebral palsy: a review. Clinical Rehabilitation, 20(12), 1023-1031. doi:
10.1177/0269215506071275 Yatkın, Ş. (2013). Visually and orthopedically handicapped adolescents’ self-
esteem levels to comprehend the effect of social attitudes towards them. Black Sea Journal of Social Sciences, 9(5), 3-12. Yorgason, J.B., Booth, A., & Johnson, D. (2008). Health, disability, and marital
quality: Is the association different for younger versus older cohorts? Re-
search on Aging, 30(6), 623–648. doi.org/10.1177/0164027508322570 Chapter 4 Chapter 4 Artificial Intelligence (AI) and Ethics in
Medicine at a Global Level: Benefits and Risks Sadi Elasan1
Yusuf Ateş2 Sadi Elasan1
Yusuf Ateş2 Sadi Elasan1 Abstract Technological developments in medicine have created significant transformations
in healthcare services and offered more effective diagnosis and treatment options
for patients. Among these advances, artificial intelligence (AI) plays a pivotal
role in a variety of medical applications, from disease diagnosis and treatment
planning to clinical research and patient care optimization. However, the rapid
development of artificial intelligence in medicine also raises ethical challenges
and concerns, including patient privacy, data security, inequality and societal
impacts. This study examines the potential benefits and risks associated with the
global use of artificial intelligence in medicine. The study presents examples and
features of global AI-based medical applications, including data-driven diagnosis
and treatment, disease prediction and early warning systems, personalized care
and treatment planning, drug development and discovery, telemedicine and
remote healthcare. Discussions of confidentiality, fairness, integrity, transparency,
patient autonomy, responsibility and accountability, change management, social
acceptance are emphasized, emphasizing the importance of ethical rules and
guidelines in the use of AI in medicine. An analysis of global publication trends
in the study of AI and ethics in medicine is also presented, providing insights
into the most influential countries and networks of collaboration. As a result,
AI has enormous potential in medicine and offers numerous benefits, including
better access to healthcare, improved diagnosis and treatment, customized care,
resource efficiency, disease prevention and early detection. However, risks related
to data security, privacy, inequality and ethical considerations must be addressed. Also, careful management, data security, ethical practices and protection of
human factors are vital in leveraging the full potential of AI in medicine. https://doi.org/10.58830/ozgur.pub128.c508 https://doi.org/10.58830/ozgur.pub128.c508 51 52 52 | Artificial Intelligence (AI) and Ethics in Medicine at a Global Level: Benefits and Risks 1. INTRODUCTION Technological developments in medicine and health provide the
transformation of health services with more effective diagnosis and treatment
options for patients. Emerging technologies such as artificial intelligence
(AI) play an important role in medicine. AI can perform operations such
as data analytics, learning, prediction, suggestion, and decision-making by
giving computer systems human-like capabilities. In medicine, AI offers
a range of applications, from disease diagnosis and treatment planning to
clinical research to optimizing patient care. However, the rapid development of AI in medicine also raises many
ethical challenges and concerns. The use of AI in medicine brings with it
several ethical issues such as patient privacy, data security, inequality, ethical
values and societal impacts. Therefore, it is important to evaluate the benefits
and risks of the use of AI in medicine at a global level. This section will examine the potential benefits and risks of the use of
AI in medicine at the global level. First, an overview of the concepts of AI
and medicine will be presented, and the potential and limitations of AI in
medicine will be discussed. Then, the relationship between ethics and AI will
be addressed, and ethical issues arising from the use of AI in medicine will
be discussed. 1.1. Artificial Intelligence and Medicine: Definitions and Concepts Today, artificial intelligence (AI) technology in the field of medicine
creates revolutionary changes in the diagnosis, treatment and care processes
of patients. AI is a discipline that gives computer systems human-like
abilities and is used in many medical applications, thanks to its ability to
perform complex operations such as data analytics, learning, prediction, and
decision-making. The concepts of Artificial Intelligence and medicine provide a fundamental
basis for understanding the use of Artificial Intelligence in medicine. Artificial Intelligence refers to a general description of artificial intelligence
technology and enables computer systems to have human-like capabilities. Medicine, on the other hand, is a science and application field that covers
diagnosis, treatment and care processes related to human health. The use of
Artificial Intelligence in medicine interacts with many different aspects of
the medical field. However, the use of Artificial Intelligence in medicine also involves some
risks. Risks such as data security and privacy, ethical and legal issues, reliance on 53 Sadi Elasan / Yusuf Ateş | Sadi Elasan / Yusuf Ateş technology, and human factors can affect the use of AI in medicine. Risks such
as completely relying on AI’s decisions, ignoring the human factor, violating
ethical rules and compromising patients’ privacy must be carefully considered. In conclusion, Artificial Intelligence holds great potential in the medical
field. However, risks such as ethical, legal, safety and human factors must
also be considered. In the future, the use of Artificial Intelligence in medicine
is expected to increase and more research and regulations are required in this
area. Artificial Intelligence can enable patients to benefit from healthcare
services in a more effective and optimized way in the medical field, but it
needs to be carefully managed and used correctly. 1.2. The Potential and Limitations of Artificial Intelligence in
Medicine The potential and limitations of AI in medicine include: Potentials: • Can use big data analytics and machine learning for disease diagnosis
and prediction. • In treatment planning, it can offer optimized treatment recommendations
based on patients’ genetic profiles and clinical data. • It can help make more effective decisions by analysing medical data in
data analytics and research. Limitations: • Data security and privacy is an important issue and medical data must
be stored securely. • Decision-making processes and outcomes of AI are controversial and
should be used in conjunction with clinical assessments by human physicians. 1.1. Artificial Intelligence and Medicine: Definitions and Concepts • Issues such as ethical issues, patient confidentiality, data use and liability
should be considered. 1.3. The Relationship Between Ethics and Artificial Intelligence The relationship between ethics and artificial intelligence is extremely
important in terms of the impact of artificial intelligence technologies on
people’s lives, social structure and cultural values. This relationship stems
from the fact that AI technologies should be used by ethical principles. Ethical values, human rights, social norms and societal expectations are
important factors to consider in the use of AI technologies. 54 4 | Artificial Intelligence (AI) and Ethics in Medicine at a Global Level: Benefits and Risks The observance of fundamental principles such as fairness, transparency,
reliability, confidentiality, responsibility and human-centeredness ensures
the ethical compliance of artificial intelligence systems. However, there are
also challenges and controversies with artificial intelligence systems. For
example, issues such as data bias, algorithm errors, discrimination, security
risks, and unemployment concerns make the ethical relevance of AI systems
questionable. However, the relationship between ethics and artificial intelligence also
presents several challenges and controversies. For example, issues such as
the risks of discrimination and inequality related to the use of AI systems,
privacy violations during data collection and use, and the interference of AI
systems in human decisions can trigger ethical discussions. Therefore, it is important to develop standards and guidelines for the
ethical use of AI technologies and to implement these standards in an ethically
acceptable manner. It is also important to raise public awareness of the
ethically correct use of AI technologies and to involve various stakeholders
in the development of AI technologies. 1.5. Features of AI-based medical applications are as follows: • Speed and Accuracy: AI can produce fast and accurate results using
big data analytics and machine learning techniques. Especially in image-
based diagnostic methods, artificial intelligence can obtain faster and more
accurate results than humans. • Learning and Development: AI can perform better over time. Machine
learning algorithms can continuously analyse data and improve themselves
to produce more accurate results. • Learning and Development: AI can perform better over time. Machine
learning algorithms can continuously analyse data and improve themselves
to produce more accurate results. • Objectivity: AI can produce objective results without being affected by
human factors. Medical decisions can be based on objective data rather than
emotions and prejudices. • Big Data Analytics: AI can analyse large amounts of data that are difficult
for humans to analyse, which can lead to new insights and discoveries. • Limitations and Challenges: AI-based medical applications also have
limitations and challenges. For example, the lack of transparency and
interpretability in AI models can lead to trust issues between healthcare
professionals and patients. Potential biases in AI models can also lead
to ethical and legal issues. Therefore, the development of transparent,
interpretable and unbiased AI models is crucial for the successful adoption
of AI-based medical practices. • Limitations and Challenges: AI-based medical applications also have
limitations and challenges. For example, the lack of transparency and
interpretability in AI models can lead to trust issues between healthcare
professionals and patients. Potential biases in AI models can also lead
to ethical and legal issues. Therefore, the development of transparent,
interpretable and unbiased AI models is crucial for the successful adoption
of AI-based medical practices. 1.4. Global AI-Based Medical Data Collection and Use Practices:
Examples and Features • Data-Driven Diagnosis and Treatment: AI can help diagnose and treat
diseases by analysing medical data using big data analytics and machine
learning techniques. For example, in image-based diagnostic methods (e.g.,
radiology, pathology), artificial intelligence can automatically analyse images
to detect medical conditions such as cancer, brain damage, and fractures,
helping doctors make quick and accurate diagnoses. • Disease Prediction and Early Warning: AI can use patients’ health data
to predict disease risk and develop early warning systems. For example, by
analysing a patient’s electronic health records and clinical data, AI can predict
the risk of diseases such as diabetes, hypertension and heart disease and alert
doctors to monitor patients at an early stage and take appropriate action. • Treatment Planning and Personalized Care: AI can plan treatments and
provide personalized treatment options using patients’ genetic, clinical and
other health data. For example, in cancer treatment, AI can analyse a patient’s
genetic profile, tumour characteristics, and other factors to determine the
most effective treatment plan and guide doctors. • Treatment Planning and Personalized Care: AI can plan treatments and
provide personalized treatment options using patients’ genetic, clinical and
other health data. For example, in cancer treatment, AI can analyse a patient’s
genetic profile, tumour characteristics, and other factors to determine the
most effective treatment plan and guide doctors. • Drug Development and Discovery: AI can accelerate drug development
processes and identify potential new drug candidates in drug discovery. • Drug Development and Discovery: AI can accelerate drug development
processes and identify potential new drug candidates in drug discovery. 55 Sadi Elasan / Yusuf Ateş | Sadi Elasan / Yusuf Ateş Using big data analytics and AI algorithm methods, AI can select the most
promising candidates from thousands of potential drug molecules and
identify them for laboratory testing, thereby accelerating drug development
processes. • Telemedicine and Remote Healthcare: AI can help diagnose and treat
patients in telemedicine and remote healthcare. Artificial intelligence can play
an important role in remote patient monitoring, diagnosis and treatment
processes, especially in remote areas, places with transportation difficulties
or in emergencies. For example, AI-powered telemedicine systems can assist
healthcare professionals in remote diagnosis, treatment planning and patient
monitoring by analysing patients’ symptoms, medical data, and test results. 1.6. Ethical Rules and Guidelines: The Use of Artificial
Intelligence in Medicine The use of artificial intelligence (AI) in medicine is regulated by ethical
rules and guidelines. Below are some ethical rules and guidelines: 6 | Artificial Intelligence (AI) and Ethics in Medicine at a Global Level: Benefits and Risks • Confidentiality and privacy policy: Confidentiality and privacy of data
are important in the use of AI. Data must be protected and processed by
legal regulations. • Confidentiality and privacy policy: Confidentiality and privacy of data
are important in the use of AI. Data must be protected and processed by
legal regulations. • Fair use: AI models should not discriminate and their results should be
used fairly and equally for all patients. • Accuracy and reliability: AI models should produce accurate and
reliable results. • Transparency and explain ability: The decision-making processes and
results of AI models should be explainable. • Patient autonomy: Patient preferences and consent are important. • Training and certification: Health professionals who will use AI should
have appropriate training and certification. • Responsibility and accountability: The use of AI should be documented
and evaluated. • Change management: Change management strategies should be used
for the use of AI. • Social acceptance and ethical discussion: There should be social
acceptance and ethical discussions about the use of AI. 2. MATERIAL A systematic data collection method, search strategy and network analysis
software were used to ensure the reliability of our study and the accuracy of
the results. Global publication trends in artificial intelligence and ethics in
medicine were identified by examining the most influential countries. In this study, global post-pandemic heart disease studies conducted
between 1999-2023 (last access date: 25 April 2023) using the “Web of
Science Core Collection (WOS, Clarivate Analytics, Philadelphia, PA,
USA)” database were examined. As a result of searches made using the
keywords “Artificial Intelligence, Ethics, Medicine” in the database, 602
suitable studies were found. Sadi Elasan / Yusuf Ateş | 57 3. RESULTS Figure 1. Frequency of publications and citations by year Figure 1. Frequency of publications and citations by year In this study, 602 published articles were taken from the WOS database. Articles were cited 5786 times (without self-citations). The average number
of citations per article is 12. H index is 41. Especially since 2018, both
the number of citations and the number of articles showed an increasing
trend. In 2023, it is estimated that the number of broadcasts will peak. The
distribution of publications and citations is shown in Figure 1. The USA ranks first in the number of articles published (n=200; 33%),
followed by the UK (n=93; 16%); Germany (n=84; 14%) and Canada
(n=80; 13%) followed. There were broadcasts from a total of 72 countries
around the world, including these first 4 countries, and Turkey ranked 11th. Countries with 12 or more publications are listed in Table 1. 58 58 | Artificial Intelligence (AI) and Ethics in Medicine at a Global Level: Benefits and Risks Table 1. Countries with at least 10 publications. Research Areas
Record Count
% of 602
USA
200
33.223
England
93
15.449
Germany
84
13.953
Canada
80
13.289
Netherlands
57
9.468
China
54
8.970
Australia
50
8.306
France
36
5.980
Switzerland
35
5.814
Italy
33
5.482
Turkey
24
3.987
Spain
19
3.156
Belgium
17
2.824
Singapore
17
2.824
India
16
2.658
Sweden
16
2.658
Austria
13
2.159
Ireland
12
1.993
Showing 18 out of 72 entries (least 12 publications) Table 1. Countries with at least 10 publications. Network analysis In this study, the “collaboration network” was analyzed using VOSviewer
(version 1.6.19, Leiden University, The Netherlands) to identify global
trends in “Artificial Intelligence and Ethics in Medicine” studies and
important topics of research in this field. 2. MATERIAL These analyzes were performed
using text mining and data visualization (bubbles maps and other graphical)
methods to ensure the accuracy and reliability of the study. Figure 2. International collaboration network map. (Collaboration between countries
is shown by lines, with thickness indicating strength, and circle/text size indicating the
level of int. collaboration) Figure 2. International collaboration network map. (Collaboration between countries
is shown by lines, with thickness indicating strength, and circle/text size indicating the
level of int. collaboration) Sadi Elasan / Yusuf Ateş | 59 Sadi Elasan / Yusuf Ateş | 59
Figure 3. Bibliographic coupling analysis for country. (The relatedness of items was
determined based on the number of references the share) Figure 3. Bibliographic coupling analysis for country. (The relatedness of items was
determined based on the number of references the share) In this study, he examined the worldwide trends and publication trends
on the subject of “Artificial Intelligence (AI) and Ethics in Medicine at a
Global Level: Benefits and Risks”. In this study, he examined the worldwide trends and publication trends
on the subject of “Artificial Intelligence (AI) and Ethics in Medicine at a
Global Level: Benefits and Risks”. The results can be used to guide research in this area and provide a
roadmap for research in Artificial Intelligence and Ethics in Medicine at a
Global Level. In conclusion, the findings reveal global trends in “Artificial
Intelligence and Ethics in Medicine at the Global Level”. 4. CONCLUSION 4.1. Potential Benefits of Artificial Intelligence in Medicine:
Implications for Patients, Healthcare and Society 4.1. Potential Benefits of Artificial Intelligence in Medicine:
Implications for Patients, Healthcare and Society Artificial intelligence offers many benefits in the medical field. These
are better access to patient’s health, higher sensitivity in diagnosis and
treatment, customized treatment and care, efficiency and rational use of
resources, disease prevention and early diagnosis, health care planning and
resource allocation, training and improvement in practice. While these
benefits enable patients to receive better health care, they increase the
efficiency of health services and provide a more rational use of resources. AI could also potentially be instrumental in disease prevention and
early detection and assist in healthcare planning and resource allocation
processes. Artificial intelligence, which also offers potential benefits in
medical education and practice, can help medical students and professionals
improve their skills. 60 Artificial Intelligence (AI) and Ethics in Medicine at a Global Level: Benefits and Risks 4.2. Potential Risks of Artificial Intelligence in Medicine: Data
Security, Privacy, Inequality and Ethical Issues The use of AI in medicine can lead to potential risks such as data security,
privacy, inequality and ethical issues. It emphasizes the need for data security
and privacy, protection of health data, and precautions against unauthorized
access risks. Inequality indicates that the use of artificial intelligence may
increase health inequalities in some regions or population groups. Finally,
ethical issues point out that the use of artificial intelligence affects issues
such as transparency, accountability, fairness and responsibility. Therefore, it
is important that the use of artificial intelligence in medicine is carried out
correctly and ethically. 4.3. Trends and Future Prospects in Artificial Intelligence and
Medicine at a Global Level Artificial intelligence is developing rapidly in medicine and has the
potential to provide many benefits. Artificial intelligence will be used more
widely in processes such as image analysis, diagnosis, treatment planning and
disease follow-up. Artificial intelligence, which will enable patients to take
an active role, can help them predict disease risks and make informed health
decisions. There is also the potential to provide more effective and accessible
healthcare to people living in low-income and rural areas. However, it is
important to pay attention to data security, ethics and accountability issues. Artificial intelligence can be used in surgical robots, health consultants,
personalized treatment plans and drug discovery processes. However, it is
also important to protect the human factor and ethical values. As a result,
artificial intelligence in medicine can enable patients to receive faster and
more accurate diagnoses and treatment, increase the efficiency of healthcare
services and improve public health. However, it is important not to ignore
data security, ethical problems and the human factor in this process. Sadi Elasan / Yusuf Ateş | 61 61 REFERENCES Abdullah, Y. I., Schuman, J. S., Shabsigh, R., Caplan, A., & Al-Aswad, L. A. (2021). Ethics of artificial intelligence in medicine and ophthalmo-
logy. Asia-Pacific journal of ophthalmology (Philadelphia, Pa.), 10(3), 289. Currie, G., Hawk, K. E., & Rohren, E. M. (2020). Ethical principles for the
application of artificial intelligence (AI) in nuclear medicine. European
Journal of Nuclear Medicine and Molecular Imaging, 47, 748-752. Davenport, T., & Kalakota, R. (2019). The potential for artificial intelligence in
healthcare. Future Healthc J 6 (2): 94–98. Guan, J. (2019). Artificial intelligence in healthcare and medicine: promises, et-
hical challenges and governance. Chinese Medical Sciences Journal, 34(2),
76-83. Hamet, P., & Tremblay, J. (2017). Artificial intelligence in medicine. Metabo-
lism, 69, S36-S40. Hindocha, S., & Badea, C. (2022). Moral exemplars for the virtuous machine:
the clinician’s role in ethical artificial intelligence for healthcare. AI and
Ethics, 2(1), 167-175. Jackson, B. R., Ye, Y., Crawford, J. M., Becich, M. J., Roy, S., Botkin, J. R., ... &
Pantanowitz, L. (2021). The ethics of artificial intelligence in pathology
and laboratory medicine: principles and practice. Academic Pathology, 8,
2374289521990784. Karimian, G., Petelos, E., & Evers, S. M. (2022). The ethical issues of the app-
lication of artificial intelligence in healthcare: a systematic scoping re-
view. AI and Ethics, 2(4), 539-551. Keskinbora, K. H. (2019). Medical ethics considerations on artificial intelligen-
ce. Journal of clinical neuroscience, 64, 277-282. LaChat, M. R. (1986). Artificial intelligence and ethics: an exercise in the moral
imagination. Ai Magazine, 7(2), 70-70. Martinho, A., Kroesen, M., & Chorus, C. (2021). A healthy debate: Exploring
the views of medical doctors on the ethics of artificial intelligence. Artifi-
cial Intelligence in Medicine, 121, 102190. Mörch, C. M., Atsu, S., Cai, W., Li, X., Madathil, S. A., Liu, X., ... & Ducret,
M. (2021). Artificial intelligence and ethics in dentistry: a scoping re-
view. Journal of dental research, 100(13), 1452-1460. Racine, E., Boehlen, W., & Sample, M. (2019, September). Healthcare uses of
artificial intelligence: Challenges and opportunities for growth. In Healt-
hcare management forum (Vol. 32, No. 5, pp. 272-275). Sage CA: Los
Angeles, CA: SAGE Publications. 62 | Artificial Intelligence (AI) and Ethics in Medicine at a Global Level: Benefits and Risks 62 Saheb, T., Saheb, T., & Carpenter, D. O. (2021). Mapping research strands of
ethics of artificial intelligence in healthcare: a bibliometric and content
analysis. Computers in Biology and Medicine, 135, 104660. 1
Yozgat Bozok University Faculty of Medicine Research and Training Hospital, Department of
Pediatrics Chapter 5
Childhood Hypertension Chapter 5 REFERENCES Solanki, P., Grundy, J., & Hussain, W. (2023). Operationalising ethics in arti-
ficial intelligence for healthcare: A framework for AI developers. AI and
Ethics, 3(1), 223-240. Childhood Hypertension Gizem Gencan1 Abstract A significant public health issue is the rising prevalence of hypertension
(HT) among children and adolescents. According to studies, controlling
and preventing HT in children will result in adequate early treatment and
a favorable prognosis, which will lessen the burden of adult cardiovascular
disease. HT is defined as systolic or diastolic blood pressure at or above
the 95th percentile (P) for age, sex, and height at least three times. When
children are initially examined, their blood pressure is normal, and blood
pressure measurements begin from age three if there are no risk factors for
hypertension. Blood pressure should be monitored yearly in children three
years and older. Children typically experience primary HT. Renal parenchymal illnesses (60–
80%), renovascular diseases (10%), and aortic coarctation (2%) are the most
frequent causes. In young patients with HT, screening tests (complete urinalysis,
hemogram, electrolytes, urea, creatinine, calcium, phosphorus, uric acid, lipid
panel, urinary and renal doppler ultrasonography, eye exam, echocardiography,
thyroid function tests, renin, and aldosterone) should be carried out. Additional
required tests are ordered in response to the patient’s new symptoms. Both medical procedures and lifestyle modifications are part of HT treatment. Recommendations for food and exercise are non-drug therapy. The most
widely prescribed medications include calcium channel blockers, vasodilators,
diuretics,- blockers, and angiotensin-converting enzyme (ACE) inhibitors. Because of their adverse effects, -blockers are not the first choice. It is advised
to use just one medicine for treatment if possible. If, despite raising the
maximum dose, blood pressure cannot be controlled by a single medication,
a second medication is administered. HT treatment aims to reduce or prevent
the risk of cardiovascular disease and damage to target organs in both the
early and late stages. https://doi.org/10.58830/ozgur.pub128.c561 https://doi.org/10.58830/ozgur.pub128.c561 63 Childhood Hypertension 64 1. Introduction A significant public health issue is the rising prevalence of hypertension
(HT) among children and adolescents. Research indicates that preventing
and managing hypertension in pediatric patients can result in timely and
effective treatment, leading to favorable outcomes and ultimately reducing
the prevalence of cardiovascular disease in the adult population. Hypertension (HT) is defined as having a systolic or diastolic blood
pressure equal to or greater than the 95th percentile (P) for an individual’s
age, sex, and height, and this must be observed on at least three distinct
occasions. During the initial assessment of pediatric patients, blood pressure
levels are typically within the normal range. However, if there are no
identifiable risk factors for hypertension, blood pressure monitoring may
commence at the age of three years. It is recommended that blood pressure
be assessed every year in children who are three years of age or older. Measuring blood pressure during each medical follow-up is recommended
for individuals with hypertension risk factors, such as obesity, diabetes
mellitus, and kidney diseases. In the case of children below the age of three,
it is recommended to measure blood pressure during each follow-up visit
if there exists a risk of hypertension due to factors such as prematurity,
low birth weight, umbilical catheterization during the neonatal period,
recurrent urinary tract infections, renal pathologies, and other related
conditions. In 2017, the American Academy of Pediatrics (AAP) revised its clinical
practice guidelines to provide a more precise definition of hypertension and
prehypertension in children. 1. Introduction Gizem Gencan 65 Blood Pressure Staging (2017 – AAP)
Blood Pressure
Stage
Children aged 1-13
Children >13 years
old
Normal Blood
Pressure
-Systolic and Diastolic Blood Pressure
<90 P
-Blood Pressure
<120/80 mmHg
High Blood Pressure
(prehypertension)
-95 P> Systolic and/or Diastolic Blood
Pressure ≥ 90 P,
or
-95P>Blood Pressure>120/80 mmHg
(whichever is lower)
(Patient's Blood Pressure is >120/80
mmHg, and this value is classified as
High Blood Pressure even if the patient
is <90P)
- Systolic Blood
Pressure between
120-129 mmHg
and Diastolic Blood
Pressure < 80 mmHg
Stage 1 HT
95P+12 mmHg > Systolic and/or
Diastolic Blood Pressure ≥95P
or
Blood Pressure between 130/80 –
139/89 mmHg
(whichever is lower)
Blood Pressure 130/80
– 139/89 mmHg
Stage 2 HT
Systolic and/or Diastolic Blood
Pressure ≥ 95P +12 mmHg,
or
Blood Pressure ≥ 140/90 mmHg
(whichever is lower)
Blood Pressure ≥
140/90 mmHg
Isolated systolic
hypertension
Systolic Blood Pressure ≥ 95P and
Diastolic Blood Pressure <90P
≥140/<90 Blood Pressure Staging (2017 – AAP) 4. Diagnostic Approach to Hypertension in Children Screening tests should be performed in the first step in pediatric patients
with HT. Afterward, necessary further tests are requested according to the
additional symptoms of the patient. 2. Blood Pressure Measurement Method The procedure involves obtaining a measurement on the right upper
arm using an appropriate cuff while the individual is seated (or supine for
newborns). Before the measurement, the individual should rest for at least
5 minutes. In cases where automatic oscillometric devices indicate elevated
blood pressure readings, verifying the results using android devices is
recommended. Childhood Hypertension 66 Age Appropriate Cuff (Cuff) Sizes
Arm circumference (cm)
Cuff width (cm)
Cuff length (cm)
Newborn
10
4
8
Infant
6-15
5
15
Child
16-21
8
21
Adolescent
22-26
10
24
Adult
27-34
13
30
Older adult
35-44
16
38 Age Appropriate Cuff (Cuff) Sizes 3. Causes of Hypertension The prevalence of primary hypertension is highest among pediatric
patients. Renal parenchymal diseases account for most cases at 60-80%,
then renovascular diseases at 10%, and aortic coarctation at 2%. Additional
etiologies encompass endocrine etiologies, pharmacological utilization,
intraventricular
hemorrhage,
bronchopulmonary
dysplasia,
essential
hypertension, and white coat hypertension. 4.1. Screening Tests • Complete urinalysis (for proteinuria) • Henogram • Electrolytes, urea, creatinine, calcium, phosphorus, uric acid • Lipid panel (triglyceride, cholesterol) • Urinary ultrasonography (USG) and renal Doppler USG • Eye examination (for HT retinopathy) • Echocardiography (ECO) (for left ventricular hypertrophy and aortic
coarctation) • Echocardiography (ECO) (for left ventricular hypertrophy and aortic
coarctation) • Hormone levels: fT4, TSH, Renin, Aldosterone 4.2. Advanced Tests • Fasting insulin and glucose (if obesity) Gizem Gencan 67 • 24 h urinary protein excretion and creatinine clearance (if there is renal
pathology) • 24 h urinary protein excretion and creatinine clearance (if there is renal
pathology) • Spot urine Na, K (in case of monogenic HT) • Spot urine Na, K (in case of monogenic HT) • Blood gases (in case of monogenic HT) • 24-hour urine VMA, HVA and 5HIAA (in Pheochromocytoma clinic) • MIBG scintigraphy (if urine metanephrines are high) • DMSA / MAG3 or DTPA (if there is an anomaly in urinary USG) • Captopril scintigraphy (if renal artery stenosis is suspected) • Renal angiography (DSA) or MR angiography (less invasive than
DSA) Targets in the treatment of HT; Targets in the treatment of HT; • To reduce or prevent the risk of cardiovascular disease and target organ
damage in the early and late stages. • The objective is to decrease blood pressure levels to less than 95 P
for primary hypertension cases without any associated organ damage
while considering factors such as gender, age, and height. Additionally, for
individuals 13 years or older, the aim is to lower blood pressure levels to
below 130/80 mmHg. • The objective is to decrease blood pressure levels to less than 95 P
for primary hypertension cases without any associated organ damage
while considering factors such as gender, age, and height. Additionally, for
individuals 13 years or older, the aim is to lower blood pressure levels to
below 130/80 mmHg. • In order to achieve a reduction in blood pressure levels for individuals
with chronic kidney disease (CKD), diabetes mellitus (DM), or hypertension
(HT) accompanied by target organ damage, it is recommended to maintain
a blood pressure level below 90 P. If proteinuria is present, the target blood
pressure level should be further reduced to below 75 P. The management of HT encompasses pharmacological interventions
and modifications to one’s daily habits and behaviors. Non-pharmacological
interventions encompass dietary and physical activity guidelines. A
recommended dietary approach involves restricting salt intake to less than
2300 mg per day while increasing consumption of minerals such as potassium
and magnesium, as well as folic acid and fiber. Additionally, a diet high in
unsaturated and low overall fat is advised. Physical activity is believed to
have advantageous effects on hypertension and risk factors associated with
cardiovascular diseases. It is recommended that patients engage in exercises
other than weight lifting. Furthermore, engaging in competitive sports
within unregulated Stage II HT is not permissible. 68 Childhood Hypertension Drug Treatment of Hypertension The pharmacological agents most frequently employed in clinical practice
include ACE inhibitors, calcium channel blockers, vasodilators, diuretics,
and β-blockers. Beta-blockers are not the preferred initial option due to their
adverse effects. It is advisable, if feasible, to pursue a monotherapy approach
for treatment. In cases where the maximum dosage of a single drug fails
to regulate blood pressure, the addition of a second drug is considered. Typically, the administration of ACE inhibitors in combination with diuretics
or vasodilators in conjunction with diuretics (or infrequently β-blockers) is
observed. The “ACD” strategy is a practical and reasonable approach for the long-
term treatment of children with hypertension. “ACD” Strategy; “A”; ACE inhibitors (ACEI) (Enalapril,..) and
angiotensin receptor blockers (ARB) (losartan,..). “ACD” Strategy; “A”; ACE inhibitors (ACEI) (Enalapril,..) and
angiotensin receptor blockers (ARB) (losartan,..). “C”;
Calcium
channel
blockers. Dihydropyridines
(nifedipine,
amlodipine) and non-dihydropyridines (verapamil, diltiazem; concomitant
use with β-blockers is contraindicated (ventricular dysfunction or AV block) “C”;
Calcium
channel
blockers. Dihydropyridines
(nifedipine,
amlodipine) and non-dihydropyridines (verapamil, diltiazem; concomitant
use with β-blockers is contraindicated (ventricular dysfunction or AV block) “D”; Diuretics (furosemide, hydrochlorothiazide [HCTZ]) “D”; Diuretics (furosemide, hydrochlorothiazide [HCTZ]) “B”; Beta-blockers (propanolol or atenolol) alone or in combination (B
+ D or B + C) are not preferred in most hypertensive children. “B”; Beta-blockers (propanolol or atenolol) alone or in combination (B
+ D or B + C) are not preferred in most hypertensive children. “B”; Beta-blockers (propanolol or atenolol) alone or in combination (B
+ D or B + C) are not preferred in most hypertensive children. If more than one drug will be used, “A” category drugs can be combined
with “C” or “D” group drugs (A + C or A + D, or A + C + D). 6.1. Diagnostic Evaluation: • Extremely high blood pressure should be confirmed (measurement
technique, cuff size, and location should be checked) • Extremely high blood pressure should be confirmed (measurement
technique, cuff size, and location should be checked) • Blood pressure should be measured from all four extremities (especially
in infants and small children) • Other causes of severe hypertension should be excluded (primary head
trauma, intracranial mass, aortic coarctation, use of sympathomimetics..) • Blood tests: CBC, reticulocyte count; serum electrolytes (Ca, BUN,
Cr,.) should be checked • Urine tests: TIT, urine culture, pregnancy test, and urine drug screening
should be done. • Other diagnostic tests: ECG, Tele-AC X-ray (heart failure), ECHO,
and Cranial CT (if there is evidence of trauma or intracranial mass) should
be evaluated. 6. Hypertensive Crisis Management and Treatment Hypertensive emergency: The presence of severe symptomatic
hypertension, characterized by a rapid increase in blood pressure, along
with one or more instances of target organ damage, is observed. Clinical
manifestations such as seizure or encephalopathy, papilledema, retinal
hemorrhage or exudate, and indications of heart failure or renal failure may
be observed. Hypertensive urgency: Severe hypertension or rapid increase in blood
pressure but no target organ damage or significant symptoms. Other findings may be present (findings suggesting the underlying cause
of hypertension): • Hematuria, proteinuria, and edema (glomerulonephritis) 69 Gizem Gencan Gizem Gencan • Ataxia, focal neurological deficit, lethargy, coma (intracranial mass or
intracranial trauma) • Decreased femoral pulses or lower extremity blood pressure (Coarctation
of the aorta) • High-dose sympathomimetic use (cocaine, amphetamine,..) • Pregnancy (eclampsia) • Pregnancy (eclampsia) • Abdominal murmur (renovascular disease) 6.2. Treatment • It is imperative to assess the patient’s airway and respiration and
ensure the airway is secured, including intubation. • It is imperative to initiate vascular access. • It is imperative to initiate vascular access. • To measure blood pressure, it is recommended to insert an intra-
arterial catheter if feasible. Alternatively, frequent blood pressure
measurements can be taken using the auscultation or oscillometric
method. • In cases of hypertensive emergency, it is recommended to initiate
intravenous therapy and to avoid reducing blood pressure by more
than 25% of the intended total decrease within the initial 8-hour
period. 70 | Childhood Hypertension 0 | Childhood Hypertension 70 • The clinical situation determines whether intravenous or oral therapy
is appropriate for managing hypertensive urgency. • It is advisable to prioritize medications that exhibit a swift
antihypertensive response. Gizem Gencan | 71 Resources: 1
Lect. Dr.; Trakya University, Department of Orthopedics and Traumatology, Türkiye.
trkesref@hotmail.com ORCID No: 0000-0002-1657-1110 Current Treatment Methods for Carpometacarpal
Joint Fractures and Dislocations Eşref Selçuk1 Resources: Simone G, Mancusi C, Hanssen H. Et al. Hypertension in children and ado-
lescents. Eur Heart J. 2022 Sep 14;43(35):3290–3301. doi: 10.1093/
eurheartj/ehac328. Lurbea E, RoseicE.A, Cruickshankd J.K, Dominiczak A.Et al. 2016 European
Society of Hypertension guidelines for the management of high blood
pressure in children and adolescents. J Hypertens 34:1887–1920 Copyri-
ght 2016 Wolters Kluwer Health, Inc. All rights reserved. Baştuğ F, Dursun İ, Tülpar S, Yel S, Nalçacıoğlu H, Kısaarslan A, Pınarbaşı A.S,
Şahin N, Çiçek S. Çocuk Nefroloji El Kitabı, Klinik Pratik Yaklaşımlar. Çocuk Nefroloji Derneği, Kayseri 2018; 33-53. Lurbe, Empar; Agabiti-Rosei, Enrico; Cruickshank, J. Kennedy; Dominiczak,
Anna; Erdine, Serap; Hirth, Asle; Invitti, Cecilia; Litwin, Mieczyslaw;
Mancia, Giuseppe; Pall, Denes; Rascher, Wolfgang; Redon, Josep; Sc-
haefer, Franz; Seeman, Tomas; Sinha, Manish; Stabouli, Stella; Webb,
Nicholas J.; Wühl, Elke; Zanchetti, Alberto (2016). 2016 European
Society of Hypertension guidelines for the management of high blood
pressure in children and adolescents. Journal of Hypertension, 34(10),
1887–1920. Phadke K, Goodyer P, Bitzan M. Hypertension. Manual of Pediatric Nephro-
logy. Springer 2014; 315-349 Hypertension: in Avner E.D, Harmon W.E, Niaudet P, Yoshikawa N, Emma F,
Goldstein S.L (eds) Pediatric Nephrology (7th ed) Springer-Verlag Berlin
Heidelberg 2016 pp. 1905-2099 Tümer N, özkaya N. Yenidoğan döneminde hipertansiyon tanı ve tedavi adü tıp
fakültesi dergisi; 2(1): 33-38 Seliem WA, Falk MC, Shadbolt B, Kent AL. Antenatal and postnatal risk fa-
ctors for neonatal hypertension and infant follow-up. Pediatr Nephrol. 2007;22(12):2081-7. nmalFlynn J. Etiology, clinical features and diagnosis of neonatal hypertension. 2014 [cited 2015, Mar 29.]. www.uptodate.com. Tej K Mattoo, MD, DCH, FRCP. Evaluation of hypertension in children and
adolescents. 2017 www.uptodate.com. Flynn JT, Kaelber DC, Baker-Smith CM, et al. Clinical Practice Guideline for
Screening and Management of High Blood Pressure in Children and
Adolescents. Pediatrics 2017; 140. Seeman T, Hamdani G, Mitsnefes M. Hypertensive crisis in children and adoles-
cents. Pediatr Nephrol`; Jun 28, 2018. 72 Chapter 6 Abstract Carpometacarpal (CMC) joint fractures and dislocations are rare hand
injuries often resulting from a fall onto a flexed wrist. Treatment options vary
as there is no consensus due to these injuries’ rarity. The CMC joints connect
the hand and carpal bones, with each joint playing a distinct role, making the
injuries examined in three groups. These joints have a robust design due to strong ligaments and unique
articulations. Extensor tendons contribute to hand stability, and injuries to
these structures can have varying clinical consequences. Despite the absence
of a universally recognized categorization method, fractures and dislocations
are generally categorized based on displacement direction, joint count, and
injury nature. Diagnosing carpometacarpal (CMC) joint fractures and dislocations involves
detailed examination and imaging, including X-rays, CT scans, and MRIs. These injuries are treated to restore the hand’s anatomy and functionality. Treatment varies widely and may include conservative measures, open
reduction, or internal fixation, with no consensus due to the rarity of such
injuries. Complications include metacarpophalangeal joint stiffness, which can lead
to contractures. Despite the severity of these injuries, both surgical and non-
surgical treatments often result in positive outcomes, with delayed treatment,
inaccurate articular restoration, and secondary fracture displacement leading
to poorer outcomes. Key to successful treatment is early detection and a comprehensive approach
including potential surgical intervention and rehabilitation. https://doi.org/10.58830/ozgur.pub128.c629 https://doi.org/10.58830/ozgur.pub128.c629 73 74 | Current Treatment Methods for Carpometacarpal Joint Fractures and Dislocations 74 | Current Treatment Methods for Carpometacarpal Joint Fractures and Dislocations 74 1. INTRODUCTION Fractures and dislocations of the Carpometacarpal (CMC) joint are
infrequently observed injuries of the hand. [1]. These injuries can occur
as isolated dislocations or as complex fracture dislocations. They typically
result from a fall onto a flexed wrist[2]. Since these injuries are rare and
often undiagnosed, there is no consensus on their treatment. Some authors
opt for closed reduction and follow-up, while others favor open reduction
and internal fixation[2–5]. The literature mostly consists of case series[6]. The CMC joint not only provides a connection between the hand and
the carpal bones but also plays a distinct role in each joint in the hand. Therefore, it’s often examined in three separate groups. These are classified
as the first CMC (thumb, preaxial), second and third CMC (central), and
fourth and fifth CMC (postaxial or ulnar) injuries[1]. This chapter will focus
on 2.-5. CMC joint fractures and dislocations. 1.1.Anatomy The carpometacarpal (CMC) joints, which connect the carpals of the
wrist and the metacarpals of the fingers, have significant clinical importance
due to their relevance in understanding various hand pathologies, such as
fractures and degenerative joint diseases. These joints showcase a notable
stability, which can be attributed to their unique anatomical configuration. The scant number of reported dislocations or fractures in these joints in the
literature could well be due to this robust design[7]. Integral to this joint stability are the strong dorsal, palmar, and interosseous
ligaments. An interesting pattern to note is the decreased stability provided
by these ligaments as one moves radially to ulnarly from the second to the
fifth CMC joint. This decrease in stability manifests as augmented mobility
in the 4.-5. CMC joints, which, regrettably, results in enhanced fracture
instability at these locations [8,9]. Further contributing to the hand’s anatomical intricacy are particular
tendons: the extensor carpi radialis longus, brevis, and ulnaris. These
tendons are notably instrumental in the onset of avulsion fractures at the
2.-3.-5. metacarpals[10]. Taking a closer look at the unique articulations within the hand, one
can appreciate the critical role that the CMC joints play in maintaining
each ray’s longitudinal arch. For instance, the trapezoid is connected to
the 2. metacarpal, the capitate to 3.metacarpal, and the hamate to the 4.-
5. metacarpal. This setup provides the distal carpal row a greater degree of 75 Eşref Selçuk rigidity compared to the more flexible proximal row, thereby striking a fine
balance between stability and mobility within the hand [11]. The crucial role of ligaments, the connective tissue that links bones
together, cannot be overstated. They provide a critical contribution to joint
integrity. Specifically, the dorsal ligaments are stronger and more distinct
than the palmar ligaments. However, the palmar ligaments, despite being
less prominent, bring substantial support to their respective joints[8,11]. The interosseous ligaments connect the third and fourth metacarpals to the
capitate and hamate. The 2.-3. metacarpals establish a stable core structure in the hand,
backed by complex bony articulations and ligaments.Key tendons, such as
the extensor carpi radialis longus and brevis, contribute to wrist extension
and grip strength. Notably, the 2.-3. CMC joints have limited flexibility,
mostly in flexion-extension. This rigidity makes these structures susceptible
to fractures under high-energy loads, such as falls, punches, or athletic
collisions. 1.1.Anatomy These injuries can be compounded by the contraction of key
extensor muscles, leading to possible bone fragment displacement and varied
clinical consequences depending on the injury’s specifics. The base of the fourth metacarpal, presenting five distinct shapes, may
form a joint exclusively with the hamate or additionally with the capitate. Its stability is derived from both ligaments and the support of adjacent
metacarpals, making isolated fractures very rare due to lack of muscular
insertions. The fifth metacarpal base, however, can become unstable due to
its ulnar slope and absence of a supportive structural pillar. Notwithstanding,
sturdy ligaments and tendons provide additional support, and these tendons
can also generate deforming force during a fracture. Both the 4.-5. CMC joints provide more flexibility than the 2.-3. CMC
joints, allowing for flexion-extension, radial-ulnar deviation, and pronation-
supination, which is crucial for grasping and palmar cupping. Their fractures
are usually the result of axial loading, often associated with dislocations, and
can be instigated by different types of trauma. Uncontested extensor forces
acting on the base of the fifth metacarpal can cause a shift of the fractured piece
towards the body and in the direction of the ulnar back side, necessitating
proper adjustment and treatment to prevent further complications. The synovial membrane forms an essential part of joint anatomy. It
encapsulates the joint, reducing friction by secreting synovial fluid, a
lubricating liquid that allows the smooth gliding of articulating bones 76 | Current Treatment Methods for Carpometacarpal Joint Fractures and Dislocations Blood supply to the CMC joints, pivotal for their normal functioning,
arises from a combination of several arteries. The 3.-4. metacarpals are
nourished by carpal arches and deep palmar arteries, while the 5. metacarpal
depends on the ulnar artery. Innervation of the CMC joints, which communicate with the central
nervous system, primarily stems from ulnar nerve, the median nerve, and
the posterior interosseous nerves. 2. FRACTURE TYPE Fractures and dislocations of the CMC joint can be classified according to
direction of displacement, joint count, and nature of the injury. Nonetheless,
a universally agreed-upon classification system for these injuries does not
exist. Studies have reported that dorsal dislocations are more common, while
volar dislocations are less frequently observed. Rarely, complex dislocations
known as divergent complex injuries can occur, accompanied by torsional
forces. Nalebuff has categorized isolated 5. CMC joint dislocations as volar
radial and volar ulnar dislocations[12]. Additionally, Cain has classified 5th
CMC joint fractures and dislocations based on the absence of the hamate
bone’s involvement[13]. A modification to the classification was proposed by Garcia-Elias, which
includes the involvement of the radial two lesser digits[14]. This classification
system describes three subtypes: trans-metacarpal injuries, carpometacarpal
injuries, and trans-carpal injuries. 3. DIAGNOSIS Diagnosing and evaluating hand injuries, particularly those involving the
carpometacarpal joint (CMCJ), requires a detailed examination and imaging
[15]. When assessing hand injuries, it is important to be thorough as
swelling can conceal deformities. Recognizing dorsal and volar deformities
is particularly significant. The Indian greeting known as ‘namaste’ test can serve as a valuable
technique to assess potential finger shortening. It is crucial to perform a
meticulous evaluation of neurovascular status to identify any possible
nerve injury[16]. Swelling can lead to median nerve involvement, which
may necessitate carpal tunnel release[17]. Motor examination is critical for
identifying ulnar nerve involvement[18]. Eşref Selçuk | 77 It is crucial to evaluate the possible detachment of specific muscles and
the thumb. In addition to the clinical examination, imaging plays a vital role
in the diagnosis and evaluation of hand injuries. Plain radiographs from different angles should be included in the
examination (figure 1). Radiographic assessment should be systematic and
should focus on IC and CMC joints. Several features need to be evaluated on
X-rays, including Gilula’s arcs, parallel articular surfaces, absence of surface
overlap, uniform joint space, and metacarpal cascade lines. Figure 1. Plain radiographs from different angles, 3-5. CMC fracture dislocation Figure 1. Plain radiographs from different angles, 3-5. CMC fracture dislocation If clinical signs warrant it, further evaluation with 3D CT or MRI should
be taken into account (figure 2). CT scans are preferred for surgical planning
and provide better visualization of cortical breaches [5]. On the other hand,
MRI excels at detecting purely trabecular fractures. Figure 2. 3D CT 3-5.CMC fracture dislocation Figure 2. 3D CT 3-5.CMC fracture dislocation 78 8 | Current Treatment Methods for Carpometacarpal Joint Fractures and Dislocations 4. TREATMENT CMC fracture dislocation 80 | Current Treatment Methods for Carpometacarpal Joint Fractures and Dislocations Figure 6. Open reduction, internal fixation and k wire Figure 6. Open reduction, internal fixation and k wire The treatment protocol of the 4.-5. metacarpal base fractures is still a
disputed issue. While conservative treatment is generally preferred for
minimally displaced fractures, surgical intervention should be considered in
cases of significant displacement or comminution. Currently, there are only a few studies that compare the functional
outcomes of closed and open treatment [16]. There is evidence suggesting
that obtaining a precise reconstruction of the original anatomical structure
through meticulous open reduction and internal fixation of intra-articular
fragments using small K-wires may result in superior functional outcomes
relative to closed reduction and stabilization with K-wires. It is crucial to
assess each case on an individual basis and tailor the treatment decision
based on patient-specific factors. 4. TREATMENT The aim in the fractures-dislocations of the CMC joint is to restore
disrupted anatomy (figure 3). A painless, stable hand that can perform
normal functions is targeted. Since these cases are rarely seen, there is no
common consensus in treatment. Several factors are considered in the evaluation of second and third
carpometacarpal joint fractures and dislocations. The fitting of the joint
surface, the attachment site of extensor carpi radialis longus and brevis
relative to the fracture are important for surgical indication. However, some
authors have expressed the opposite view due to partial immobility of this
joint. Figure 3. Disrupted anatomy of 2-5 CMC joints Figure 3. Disrupted anatomy of 2-5 CMC joints In the literature, there are cases followed by conservative treatment and
open reduction (figure 4). Since the ligaments cannot be evaluated accurately
without directly seeing the injured area in surgery, many authors suggest
open reduction & K-wire [2,19]. Based on the fracture type, cases using
tension band, screw, or suture anchor have also been reported. ,
Figure 4. Open reduction, k wire fixation of 2-5. CMC joint Figure 4. Open reduction, k wire fixation of 2-5. CMC joint Eşref Selçuk | 79 There isn’t a widely agreed-upon treatment strategy for fractures of
the bases of the 4.-5. metacarpals. Utilizing a compact dorsal arm splint
for conservative immobilization is an alternative considered for clinical
situations involving non-displaced fractures and well-aligned joints after
closed reduction, allowing for fracture union to take place. However, in the
case of significant displacement, fragmentation, or complete tear, closed
reduction and percutaneous K wire or open reduction and internal fixation
are recommended. Some studies indicate that conservative management can be effective for
fractures involving the joint at the base of the 5. Metacarpal [8]. However,
it is stated that osteoarthritis development can occur with conservative
treatment in displaced intra-articular fractures and surgical intervention
may be required in some cases. Other studies show that even after surgical
treatment, some patients may experience sustained pain. There is a limited body of literature concerning fractures at the base of
the 4. metacarpal. Typically, these fractures are found in conjunction with
5. CMC dislocations or hamate fractures (figure 5). Open reduction and
internal fixation are advised in the surgical treatment of hamato-metacarpal
fracture dislocations (figure 6). Figure 5. Hamate fracture with 4-5. CMC fracture dislocation Figure 5. Hamate fracture with 4-5. 5. COMPLICATION A common complication of CMC joint fracture dislocation is
metacarpophalangeal (MCP) joint stiffness, potentially leading to extension
contractures. This issue, resulting from factors like swelling-induced MCP
joint extension, postoperative patient comfort habits, and interossei muscle
injuries, is multifaceted. Prompt surgical intervention is recommended to release hematoma,
reduce hand swelling, and prevent ischemic injury to the interossei muscles. Throughout the treatment of the CMC joint using K-wires, the MCP
joint is maintained in full flexion to prevent any tethering of the skin or
soft tissues. K-wires are inserted from both the radial and ulnar aspects of
the hand to further mitigate the risk of tendon tethering. Postoperatively, ef Selçuk | 81 | 81 Eşref Selçuk | 81 Eşref Selçuk | 81 patients diligently elevate their hand and engage in supervised therapy that
specifically targets flexion of the MCP joint. If stiffness persists, early-stage
rubber band traction is utilized, with established contractures potentially
requiring surgical release. 6. PROGNOSIS AND CONCLUSION Regardless of the severity of CMC joint fracture dislocations, positive
results are typically attained through the utilization of both non-surgical and
surgical treatment approaches. Outcomes are enhanced by the hand’s ability
to compensate for loss in motion through adjacent joints. However, poor
outcomes are tied to delayed treatment, inaccurate articular restoration,
concurrent neurological injuries, and secondary fracture displacement. Various treatments such as CMC joint arthrodesis, interposition
arthroplasty, and CMC joint resection have been successfully employed. Anatomical reduction with adequate stabilization is key to satisfactory
results. The most favorable results observed in individuals undergoing open
reduction and K-wire. Fractures occurring at the bases of the 2.-3. metacarpals typically exhibit
improved outcomes when treated through open reduction and internal
fixation. Conversely, fractures involving the base of the 4. metacarpal,
though infrequent, tend to demonstrate more positive long-term results
with open reduction and internal fixation. The management of fractures at
the base of the 5. metacarpal remains a subject of debate, as both surgical
and non-surgical approaches frequently result in persistent pain for patients. In conclusion, early detection and a comprehensive approach to
treatment, which could include surgical and non-surgical management
and rehabilitation, often lead to favorable outcomes in CMC joint fracture
dislocations[20]. 82 2 | Current Treatment Methods for Carpometacarpal Joint Fractures and Dislocations 7.REFERENCE [1]
Hammert WC, Boyer MI, Bozentka DJ, Calfee RP. ASSH Manual of
Hand Surgery. Wolters Kluwer Health; 2012. [2]
Bushnell BD, Draeger RW, Crosby CG, Bynum DK. Management of Int-
ra-Articular Metacarpal Base Fractures of the Second Through Fifth Me-
tacarpals. Journal of Hand Surgery 2008;33. https://doi.org/10.1016/j. jhsa.2007.11.019. [3]
Mueller JJ. Carpometacarpal dislocations: Report of five cases and review
of the literature. J Hand Surg Am 1986;11:184–8. https://doi.org/htt-
ps://doi.org/10.1016/S0363-5023(86)80048-X. [4]
Frick L, Mezzadri G, Yzem I, Plotard F, Herzberg G. Luxations carpomé-
tacarpiennes fraîches des doigts longs. Étude à propos de 100 cas. Chir
Main 2011;30:333–9. https://doi.org/10.1016/j.main.2011.06.010. [5]
Büren C, Gehrmann S, Kaufmann R, Windolf J, Lögters T. Manage-
ment algorithm for index through small finger carpometacarpal fractu-
re dislocations. European Journal of Trauma and Emergency Surgery
2016;42:37–42. https://doi.org/10.1007/s00068-015-0611-z. [6]
Hartwig RH, Louis DS, Arbor A, From M. THE JOURNAL OF BONE
AND JOINT SURGERY Multiple Carpometacarpal Dislocations A RE-
VIEW OF FOUR CASES. n.d. [7]
Bentley G. European Surgical Orthopaedics and Traumatology: The
EFORT Textbook. Springer Berlin Heidelberg; 2014. [8]
Bushnell BD, Draeger RW, Crosby CG, Bynum DK. Management of Int-
ra-Articular Metacarpal Base Fractures of the Second Through Fifth Me-
tacarpals. Journal of Hand Surgery 2008;33. https://doi.org/10.1016/j. jhsa.2007.11.019. [9]
Hammert WC, Boyer MI, Bozentka DJ, Calfee RP. ASSH Manual of
Hand Surgery. Wolters Kluwer Health; 2012. [10] Büren C, Gehrmann S, Kaufmann R, Windolf J, Lögters T. Manage-
ment algorithm for index through small finger carpometacarpal fractu-
re dislocations. European Journal of Trauma and Emergency Surgery
2016;42:37–42. https://doi.org/10.1007/s00068-015-0611-z. [11] Bhardwaj P, Sivakumar BS, Vallurupalli A, Pai M, Sabapathy SR. Fracture
dislocations of the carpometacarpal joints of the fingers. J Clin Orthop
Trauma 2020;11. https://doi.org/10.1016/j.jcot.2020.05.039. [12] Nalebuff EA. Isolated anterior carpometacarpal dislocation of
the fifth finger: Classification and case report. Journal of Tra-
uma - Injury, Infection and Critical Care 1968;8. https://doi. org/10.1097/00005373-196811000-00017. 83 Eşref Selçuk Eşref Selçuk Eşref Selçuk Eşref Selçuk [13] Cain JE, Shepler TR, Wilson MR. Hamatometacarpal fracture-disloca-
tion: Classification and treatment. Journal of Hand Surgery 1987;12. https://doi.org/10.1016/S0363-5023(87)80064-3. [14] Garcia-Elias M, Bishop AT, Dobyns JH, Cooney WP, Linscheid RL. Trans-
carpal carpometacarpal dislocations, excluding the thumb. Journal of Hand
Surgery 1990;15. https://doi.org/10.1016/S0363-5023(09)90011-9. [15] Frick L, Mezzadri G, Yzem I, Plotard F, Herzberg G. Luxations carpomé-
tacarpiennes fraîches des doigts longs. Étude à propos de 100 cas. Chir
Main 2011;30:333–9. https://doi.org/10.1016/j.main.2011.06.010. [16] Cates R, Rhee P, Kakar S. Multiple Volar Carpometacarpal Dislocations:
Case Report/Review of the Literature. 1
Lecturer Dr. Hacettepe University, Faculty of Parmacy, epartment of Biochemistry
seyhan.turk@hacettepe.edu.tr, ORCID ID: 0000-0003-3843-4173 7.REFERENCE J Wrist Surg 2016;05. https://doi. org/10.1055/s-0036-1580602. [17] Weiland AJ, Lister GD, Villarreal-Rios A. Volar fracture dislocations of
the second and third carpometacarpal joints associated with acute carpal
tunnel syndrome. Journal of Trauma - Injury, Infection and Critical Care
1976;16. https://doi.org/10.1097/00005373-197608000-00014. [18] Gore DR. Carpometacarpal dislocation producing compression of the
deep branch of the ulnar nerve. J Bone Joint Surg Am 1971;53. https://
doi.org/10.2106/00004623-197153070-00016. [19] Gehrmann S V., Kaufmann RA, Grassmann JP, Lögters T, Schädel-Höpf-
ner M, Hakimi M, et al. Fracture-dislocations of the carpometacarpal
joints of the ring and little finger. Journal of Hand Surgery: European
Volume 2015;40:84–7. https://doi.org/10.1177/1753193414562706. [20] Lawlis JF, Gunther SF, D4 M, Washington DC. THE JOURNAL OF
BONE AND JOINT SURGERY Carpometacarpal Dislocations LONG-
TERM FoLLoww uP*. n.d. Chapter 7 The Impact of Biochemical Alterations in the
Tumor Microenvironment on Cancer Progression
and Treatment Seyhan Turk1 Abstract The tumor microenvironment (TME) plays a critical role in cancer progression
and treatment response. Recent studies have revealed that biochemical
alterations within the TME can significantly influence tumor behavior and
therapeutic outcomes. Alterations in the TME, such as changes in pH, hypoxia, and nutrient
availability, have been shown to promote cancer cell survival and growth. Acidic pH conditions within the TME enhance tumor invasiveness and
metastasis while conferring resistance to conventional therapies. Hypoxia,
caused by insufficient oxygen supply, not only promotes genetic instability
and immune evasion but also induces resistance to radiation and certain
chemotherapeutic agents. Additionally, nutrient deprivation within the TME
can activate survival pathways in cancer cells, leading to treatment resistance. Understanding the biochemical alterations in the TME has led to the
development of novel therapeutic approaches. Strategies to modulate the TME,
such as targeting angiogenesis, reversing immunosuppression, and normalizing
the microenvironment, have shown promise in preclinical and clinical studies. Combining conventional therapies with agents targeting the TME holds
potential to overcome treatment resistance and improve patient outcomes. In conclusion, the biochemical alterations within the TME significantly impact
cancer progression and treatment response. Recognizing these alterations
and their influence on therapeutic outcomes is crucial for developing effective
treatment strategies. Continued research in this area is vital to unravel the
complexity of the TME and identify novel therapeutic targets for improving
cancer patient outcomes. https://doi.org/10.58830/ozgur.pub128.c626 https://doi.org/10.58830/ozgur.pub128.c626 85 | The Impact of Biochemical Alterations in the Tumor Microenvironment on Cancer... 86 Introduction The tumor microenvironment consists of various cellular and non-cellular
components surrounding the tumor. Biochemical changes in the tumor
microenvironment may have important effects on cancer progression
and treatment (Arneth, 2020). Biochemical changes in the tumor
microenvironment can promote tumor growth and invasion. Factors secreted
by tumor cells and stromal cells within the microenvironment can stimulate
cell proliferation, angiogenesis, and tissue remodeling, allowing the tumor
to expand and invade neighboring tissues (Denton et al., 2018). Biochemical factors in the microenvironment, such as cytokines and
chemokines, can recruit immunosuppressive cells, including regulatory T
cells and myeloid-derived suppressor cells, which reduce the anti-tumor
immune response (Denton et al., 2018; Wu et al., 2015). The altered
composition of extracellular matrix components, increased interstitial
pressure, and impaired blood supply can limit the delivery and effectiveness
of chemotherapy drugs and radiation therapy (Wu et al., 2015; Multhoff et
al., 2012). In addition, the microenvironment may provide survival signals
to cancer cells, protecting them from the cytotoxic effects of treatment
(Hinshaw et al., 2019). The tumor microenvironment undergoes angiogenic remodeling,
characterized by the formation of new blood vessels to meet the increased
nutrient and oxygen demands of the growing tumor (Fukumura et al.,
2007). Biochemical factors secreted by cancer cells, such as vascular
endothelial growth factor (VEGF), stimulate angiogenesis and aggregation
of endothelial cells (Nicosia, 1998; Byrne et al., 2005). This facilitates the
establishment of an extensive network of blood vessels within the tumor. 1. Oncogenes and Tumor Suppressor Genes Oncogenes are genes that, when mutated or activated, promote cell
growth and division (Feldman et al., 1991). Tumor suppressor genes normally
regulate cell growth and division and may prevent cancer development
(Jones et al., 2009). Changes in these genes can upset the balance between
cell proliferation and cell death (Ryan et al., 2001). Proto-oncogenes are the main regulators of biological processes and
are found in normal cells. It can act as proto-oncogenes, growth factors,
signal transducers, and nuclear transcription factors. The genomes of
mammals and birds contain several proto-oncogenes that regulate normal
cell differentiation and proliferation (Müller, 1986). Changes in these genes
that affect the regulation of their behavior or the structure of their encoded Seyhan Turk | 87 Seyhan Turk 87 proteins can emerge as oncogenes in cancer cells. When such oncogenes
are produced, they promote cell proliferation and play a crucial role in the
pathogenesis of cancer. There are two categories of physical mutations that
result in the activation of proto-oncogenes: those that cause differences in
the structure of the encoded protein and those that cause dysregulation of
protein expression (Jan et al., 2019; Abel et al., 2009). Point mutations
of RAS proto-oncogenes and chromosomal translocations producing
chimeric genes such as Philadelphia translocation (BRC-ABL) are examples
of mutations that affect structure (Abel et al., 2009; Bataille et al., 2017;
Kurebayashi, 2001; Klinakis et al., 2006). Activation of proto-oncogenes results in their conversion to oncogenes;
To date, 50 to 60 oncogenes have been identified (Lee et al., 2010). Each proto-oncogene promoter allows the gene to respond to a variety
of physiological signals. Depending on the metabolic requirements of the
cell, a proto-oncogene may be expressed at very low levels; however, under
certain conditions, the expression of the gene can be significantly induced
(Lee et al., 2010). The activation mechanisms of proto-oncogenes are as follows: a) Chromosomal translocation of a proto-oncogene from a non-
replicating location to an adjacent location where it can be replicated
(chromosomal translocation of the MYC oncogene in human Burkitt
lymphoma). An example of a chromosomal translocation involving the MYC oncogene
is the t(8;14) translocation commonly found in Burkitt lymphoma. In
this translocation, a portion of chromosome 8 containing the MYC gene
fuses with a portion of chromosome 14, resulting in dysregulation of MYC
expression. MYC oncogene plays a crucial role in cell cycle regulation,
cellular growth and differentiation. 1. Oncogenes and Tumor Suppressor Genes Deregulated expression of MYC due
to the t(8;14) translocation leads to constitutive activation of the MYC
signaling pathway. This pathway is involved in various cellular processes and
is involved in tumor progression. MYC levels are tightly regulated under
normal conditions. However, MYC is overexpressed in the presence of the
t(8;14) translocation (Quatrin et al., 2021). The displaced MYC gene is
now under the control of regulatory elements from the immunoglobulin
heavy chain gene (IgH) on chromosome 14, resulting in increased MYC
expression. The overexpressed MYC protein forms a heterodimer with
its partner protein Max. This MYC-Max complex binds to specific DNA
sequences called E-boxes in the promoters of target genes, leading to their
activation. Target genes regulated by MYC are involved in cell proliferation, The Impact of Biochemical Alterations in the Tumor Microenvironment on Cancer... 88 metabolism and apoptosis (Lüscher et al., 2012; Nie et al., 2012). One of
the primary functions of MYC is to promote cell cycle progression from
G1 phase to S phase. MYC activates the expression of genes involved in
cell cycle regulation, such as cyclins and cyclin-dependent kinases (CDKs),
which direct cell division. MYC also supports metabolic reprogramming
to support the increased energy demands of rapidly dividing cancer cells. It increases nutrient availability for cancer cell growth by activating genes
involved in glucose uptake, glycolysis and glutamine metabolism. Normally,
MYC regulates cell death and apoptosis. However, in the context of
MYC translocation, its dysregulated expression may impair apoptosis and
allow cancer cells to escape programmed cell death. In addition, MYC
overexpression can trigger cellular senescence, a state of irreversible growth
arrest. The dysregulated MYC signaling pathway promotes uncontrolled cell
proliferation, genomic instability, and resistance to cell death mechanisms. These factors contribute to tumor growth, metastasis, and progression in
Burkitt’s lymphoma and potentially other cancers associated with MYC
dysregulation (Rohrberg et al., 2020). b) Point mutation of a proto-oncogene in which the substitution of a
single base by another base results in the substitution of an amino
acid in the oncoprotein (a point mutation at codon 12 of the RAS
oncogene). It is a well-known genetic change found in several types of cancer,
including colorectal cancer, lung cancer, and pancreatic cancer. This mutation
affects the RAS gene, specifically one of three isoforms: KRAS, NRAS, or
HRAS. 1. Oncogenes and Tumor Suppressor Genes The mutation results in the substitution of a single nucleotide that
results in an amino acid change in the protein product of the RAS gene
(Miyakura et al., 2002). The most common mutation at codon 12 is the
replacement of glycine (G) with valine (V), aspartic acid (D), cysteine (C),
or arginine (R). This substitution disrupts the intrinsic GTPase activity of
the RAS protein, preventing it from hydrolyzing GTP to GDP, which is
essential for normal RAS function and regulation. The mutated RAS protein
is locked in its active GTP-bound state, leading to sustained activation of
downstream signaling pathways involved in cell growth and survival. RAS
is an important upstream regulator of the mitogen-activated protein kinase
(MAPK) pathway (Gerber et al., 2022; Farr et al., 1988). The mutated RAS
protein lacks efficient GTPase activity and disrupts normal down-regulation
of RAS signaling. This leads to sustained activation of downstream effectors
even in the absence of growth factor stimulation. Constitutive activation
of RAS signaling promotes uncontrolled cell growth, survival, and escape
of growth inhibitory signals. It also contributes to increased angiogenesis, Seyhan Turk | 89 89 Seyhan Turk Seyhan Turk invasion, and metastasis and ultimately promotes tumor progression
(Sparmann et al., 2004). c) Gene amplification by including multiple copies of an oncogene results
in increased oncoprotein production (c-MYC in neuroblastoma). c) Gene amplification by including multiple copies of an oncogene results c) Gene amplification by including multiple copies of an oncogene results
in increased oncoprotein production (c-MYC in neuroblastoma). Neuroblastoma is a childhood cancer that arises from immature nerve
cells called neuroblasts. It is characterized by abnormal growth of these cells
in the adrenal glands, abdomen, chest, or spinal cord (David et al., 1989). Amplification or overexpression of the c-MYC oncogene is commonly
observed in neuroblastoma. This can occur through a variety of mechanisms,
including gene amplification, chromosomal rearrangements, or dysregulation
of transcriptional control elements. Dysregulation of c-MYC contributes to
the uncontrolled cell proliferation, survival, and differentiation observed
in neuroblastoma. Dysregulated c-MYC in neuroblastoma affects various
cellular processes and signaling pathways. Overexpression of c-MYC in
neuroblastoma leads to increased cell proliferation and decreased apoptosis,
promoting tumor growth. c-MYC also affects the balance between cell
differentiation and apoptosis. Normally, c-MYC expression is downregulated
during cell differentiation. However, dysregulated c-MYC expression in
neuroblastoma inhibits differentiation and contributes to tumor progression
by promoting cell survival. 1. Oncogenes and Tumor Suppressor Genes c-MYC stimulates the production of pro-
angiogenic factors (Hatzi et al., 2002). In neuroblastoma, dysregulated
c-MYC can enhance angiogenesis. Similar to other cancers, dysregulated
c-MYC in neuroblastoma drives metabolic reprogramming to meet the energy
demands of rapidly dividing cells. It promotes glucose uptake, glycolysis
and glutamine metabolism, ensuring tumor cell growth and survival. c-MYC
dysregulation may contribute to genomic instability by leading to the
accumulation of additional genetic changes in neuroblastoma cells. Genomic
instability is a hallmark of cancer and can further increase tumor progression
and heterogeneity. Understanding the role of dysregulated c-MYC in
neuroblastoma is crucial for developing targeted therapies. Efforts are being
made to develop drugs that specifically inhibit c-MYC or target downstream
pathways affected by c-MYC dysregulation. By targeting c-MYC and its
associated signaling pathways, the researchers aim to disrupt neuroblastoma
cell growth and improve patient outcomes (Nisar et al., 2020). d) Combining a gene that promotes transcription (promoter gene) near
the proto-oncogene causes overexpression of the gene (mechanism of
retrovirus carcinogenicity). Retroviruses are a family of RNA viruses that have the ability to integrate
their viral DNA into the host cell’s genome. They can cause carcinogenicity The Impact of Biochemical Alterations in the Tumor Microenvironment on Cancer... 90 (cancer development) through several mechanisms. Retroviruses can
integrate their viral DNA into the host cell’s genome, usually near or within
the genes involved in cell growth regulation. This integration can disrupt
the normal regulation of these genes, leading to uncontrolled cell growth
and potentially their transformation into cancer cells. Viral integration can
activate oncogenes or contribute to carcinogenesis by inactivating tumor
suppressor genes. Some retroviruses carry oncogenes, which are genes that
can induce cancer development. These viral oncogenes are derived from
cellular genes captured during previous infections and incorporated into the
viral genome. When the retrovirus infects a host cell, the viral oncogene can
be expressed and contribute to cellular transformation by altering normal
cell growth and survival pathways (Sahu et al., 2022). Retroviral infection
can suppress the immune system and allow cells to multiply that would
otherwise be eliminated by immune surveillance. This immunosuppression
can create a conducive environment for cancer development and progression. Retroviral infection can lead to chronic inflammation, which is known to
play a role in promoting tumor growth and progression. Inflammation
produces reactive oxygen species and inflammatory mediators, which can
damage DNA, promote cell proliferation, and create an environment that
promotes cancer growth. 1. Oncogenes and Tumor Suppressor Genes Immortalization and Telomere Retroviruses can
induce cellular immortalization by activating telomerase, an enzyme that
lengthens telomeres, the protective ends of chromosomes. Telomerase
activation allows cells to transcend the natural limits in cell division and
continue to proliferate, which is a characteristic feature of cancer cells. It
is important to note that retroviruses have varying levels of carcinogenic
potential. For example, certain retroviruses such as human T-cell
lymphotropic virus type 1 (HTLV-1) and human immunodeficiency virus
(HIV) have been strongly associated with certain types of cancer, such as
adult T-cell leukemia/lymphoma and AIDS (Romanish et al., 2010; Fan,
1994). 2. Genetic Mutations Mutations in genes play a crucial role in the development of cancer. Oncogenes, tumor suppressor genes, and other genes involved in DNA
repair, cell cycle regulation, and apoptosis (programmed cell death) can
undergo mutations (Grandér, 1998). Cancer is a genetic disease while many factors can contribute to cancer
development, genetic mutations are the driving force behind the onset and
progression of most cancers (Aranda-Anzaldo, 2001). Seyhan Turk | 91 91 Seyhan Turk | 91 Seyhan Turk | 91 Driver Mutations: Driver mutations are changes in certain genes that
give cancer cells a growth advantage. These mutations directly contribute
to the development and progression of cancer. Driver mutations can occur
in oncogenes (genes that promote cell growth) or tumor suppressor genes
(genes that prevent uncontrolled cell growth). Examples of commonly
mutated oncogenes include KRAS, EGFR, and BRAF, while tumor
suppressor genes such as TP53 and PTEN are frequently mutated in various
cancers (Temko et al., 2018; Li, 2016). Passenger (Passanger) Mutations: Passenger mutations are genetic
changes that occur during cancer development but do not directly contribute
to tumor growth. These mutations are a result of the genomic instability and
chaotic nature of cancer cells. Although passenger mutations do not drive
cancer progression, they can be used to trace a tumor’s evolutionary history
and provide insight into its cellular diversity (Bozic et al., 2016). Germline Mutations: Germline mutations are inherited genetic changes
found in every cell of an individual’s body. These mutations are passed
on from parents and may predispose individuals to an increased risk of
developing certain types of cancer. For example, mutations in the BRCA1
and BRCA2 genes significantly increase the risk of breast and ovarian cancer
(Iau et al., 2001). Somatic Mutations: Somatic mutations are acquired genetic changes that
occur in certain cells throughout a person’s life. These mutations are not
inherited and are usually caused by exposure to environmental factors such
as radiation, chemicals, and tobacco smoke. Somatic mutations accumulate
over time and can lead to the development of cancer. For example, exposure
to UV radiation from the sun can cause mutations in skin cells, increasing
the risk of skin cancer (Martincorena et al., 2015). Different types of mutations can leave certain patterns or signatures in
the cancer genome. These mutation signatures can provide insight into
the underlying causes of genetic mutations and help identify potential
carcinogens. 2. Genetic Mutations For example, exposure to tobacco smoke leaves a distinct
mutational signature characterized by certain types of DNA changes
(Alexandrov et al., 2016). 3. Cell Signaling Pathways Various signaling pathways control cell growth, survival, and proliferation. Changes in these pathways can lead to uncontrolled cell division and evasion
of cell death mechanisms. For example, the Ras-Raf-MAPK pathway and
the PI3K-AKT-mTOR pathway are frequently dysregulated in cancer. Cell 92 The Impact of Biochemical Alterations in the Tumor Microenvironment on Cancer... signaling pathways play a crucial role in normal cellular processes, including
cell growth, proliferation, differentiation and survival. However, when these
signaling pathways become dysregulated, it can lead to the development and
progression of cancer (Harvey, 2019). Oncogenic mutations or changes can occur in components of signaling
pathways such as receptor tyrosine kinases (RTKs), downstream signaling
molecules, or transcription factors. These mutations can trigger uncontrolled
cell growth and proliferation, leading to constitutive activation of signaling
pathways. Examples include mutations in the EGFR gene in lung cancer
or the BRAF gene in melanoma that result in hyperactive MAPK signaling
(Lundby et al., 2019). Many cancers take advantage of growth factor
signaling pathways, such as the epidermal growth factor receptor (EGFR)
pathway, to promote cell survival and proliferation. Dysregulation of
growth factor receptors or their downstream effectors can lead to sustained
activation of the pathway, promoting tumor growth. Targeting these
pathways with specific inhibitors has become a successful therapeutic
strategy in some cancers (Yewale et al., 2013). The PI3K/AKT/mTOR
pathway is frequently dysregulated in cancer. Activation of this pathway
supports cell survival, growth and metabolism. Mutations in components
of the PI3K pathway or upstream regulators such as loss of PTEN lead
to increased signaling along this pathway, contributing to uncontrolled
cell growth and resistance to therapies (Martelli et al., 2011). The Wnt/β-
Catenin pathway plays a crucial role in embryonic development and tissue
homeostasis. Dysregulation of this pathway can occur through mutations
in components of the Wnt pathway or stabilization of β-catenin. Abnormal
activation of the Wnt/β-Catenin pathway promotes cell proliferation and
is associated with a variety of cancers, including colorectal cancer (Bian
et al., 2020). Notch signaling pathway regulates cell fate determination,
differentiation and tissue development. Dysregulation of Notch signaling
has been associated with numerous cancers, including leukemia, breast
cancer, and pancreatic cancer. Abnormal activation of Notch signaling can
disrupt normal cellular differentiation, leading to uncontrolled cell growth
and tumorigenesis (Yin et al., 2010). The Hedgehog pathway is involved in
embryonic development and tissue homeostasis. 3. Cell Signaling Pathways Mutations in components
of the Hedgehog pathway, such as Flattened (SMO) or Patched (PTCH),
can cause aberrant activation of the pathway, contributing to a variety of
cancers, including basal cell carcinoma and medulloblastoma (Skoda et al.,
2018) Seyhan Turk | 93 Seyhan Turk | 93 4. Metabolism 94 | The Impact of Biochemical Alterations in the Tumor Microenvironment on Cancer... These metabolic changes give cancer cells a selective advantage
that supports their growth, survival, and ability to adapt to the tumor
microenvironment. Targeting cancer cell metabolism has emerged as an
exciting area of cancer research with the aim of developing treatments that
specifically disrupt the metabolic weaknesses of cancer cells while sparing
normal cells (Vander Heiden, 2011). 4. Metabolism Cancer cells exhibit altered metabolism compared to normal cells. They
often rely on glycolysis (the breakdown of glucose) even in the presence of
oxygen, known as the Warburg effect. This metabolic shift provides cancer
cells with the necessary building blocks for rapid proliferation. Cancer cells
exhibit different metabolic changes compared to normal cells, a phenomenon
known as “metabolic reprogramming”. These changes in metabolism are
essential to support increased energy demands, rapid proliferation and
survival of cancer cells. Cancer cells often rely on glycolysis, which is the breakdown of glucose,
even in the presence of oxygen (aerobic conditions); this is a less efficient way
of producing energy in mitochondria compared to oxidative phosphorylation. This metabolic switch enables cancer cells to produce ATP and the building
blocks necessary for cell growth and proliferation more quickly. Intermediate
products of glycolysis can also be directed to support other biosynthetic
pathways needed for cell division (Lincet et al., 2015). Cancer cells have an
increased demand for an amino acid, glutamine. Glutamine acts as a carbon
source for the synthesis of nucleotides, lipids and non-essential amino
acids that support the high biosynthetic needs of cancer cells. Additionally,
glutamine metabolism contributes to the production of antioxidants and
helps cancer cells manage oxidative stress (Desideri et al., 2015). Cancer
cells exhibit enhanced lipid biosynthesis to provide membrane building
blocks and support cell growth. They regulate de novo fatty acid synthesis
and increase lipid intake. Lipids also play a role in signaling pathways and
may promote cancer cell survival and migration. Rapidly dividing cancer
cells require a large supply of nucleotides for DNA and RNA synthesis. Cancer cells regulate pathways involved in nucleotide biosynthesis to meet
this demand. Increased nucleotide synthesis also provides an opportunity
for therapeutic targeting of cancer metabolism (Robinson et al., 2020;
Mashima et al., 2009). Some cancers rely on glycolysis, while others exhibit
enhanced mitochondrial metabolism. This includes increased oxidative
phosphorylation, fatty acid oxidation and tricarboxylic acid (TCA) cycle
activity. Mitochondrial metabolism is crucial in certain types of cancer to
provide ATP, biosynthetic precursors and maintain redox balance. Cancer
cells often have increased reactive oxygen species (ROS) levels due to their
altered metabolism and high proliferation rate. To manage elevated ROS,
cancer cells upregulate antioxidant defense systems such as the glutathione
pathway and thioredoxin system to maintain redox homeostasis and promote
cell survival (Alberghina et al., 2012). 5. Angiogenesis Tumor growth and progression requires the development of new blood
vessels, a process known as angiogenesis. Cancer cells have the ability to
secrete various factors that promote angiogenesis to ensure adequate blood
flow to support increased nutrient and oxygen demands. Angiogenic factors such as vascular endothelial growth factor (VEGF),
fibroblast growth factor (FGF), platelet-derived growth factor (PDGF),
and angiopoietins are produced and released by cancer cells. These factors
stimulate the growth and migration of endothelial cells, the blood vessel
building blocks (Carmeliet et al., 2011). Angiogenic factors released by
cancer cells bind to specific receptors on the surface of endothelial cells,
activating signaling pathways that promote cell proliferation, migration
and formation of new blood vessels. This process allows endothelial cells to
invade surrounding tissue and form capillary shoots (Carmeliet et al., 2011). Remodeling of the extracellular matrix is crucial for the formation of new
blood vessels. Cancer cells and stromal cells in the tumor microenvironment
secrete proteolytic enzymes such as matrix metalloproteinases (MMPs),
which degrade the extracellular matrix, creating a pathway for endothelial
cells to migrate and form new vasculature (Gálvez et al., 2001). Endothelial
cells proliferate and form sprouts that lengthen and connect with nearby
vessels to form a network of new blood vessels. This process is called
neovascularization or angiogenesis. Newly formed blood vessels support the
growth and survival of the tumor by supplying the growing tumor with
oxygen, nutrients, and growth factors (Gálvez et al., 2001). The tumor microenvironment, composed of stromal cells, immune
cells, and components of the extracellular matrix, plays a crucial role in
regulating angiogenesis. Cancer cell interactions with surrounding stromal
cells, including cancer-associated fibroblasts and immune cells, can modulate
the production of angiogenic factors and influence the angiogenic response
(Payne et al., 2011). Targeting angiogenesis has been a successful therapeutic
strategy in cancer treatment. Drugs that inhibit angiogenesis such as anti-
angiogenic antibodies (eg, bevacizumab) and small molecule inhibitors (eg, Seyhan Turk | 95 95 Seyhan Turk tyrosine kinase inhibitors that target VEGF receptors) have been developed
and are used in combination with other therapies to limit blood flow to
tumors to reduce their growth and improve patient outcomes (Petrovic,
2016). 6. Epigenetic Changes Epigenetic modifications include changes in DNA and associated proteins
without altering the underlying genetic sequence. These modifications can
have profound effects on gene expression and play a crucial role in numerous
biological processes, such as cancer (Zheng et al., 2008). DNA methylation is a prevalent epigenetic modification involving
the addition of a methyl group to DNA molecules, typically at cytosine
residues within CpG dinucleotides. DNA methylation can influence gene
expression by preventing transcription factors from binding to regulatory
regions of genes, thereby suppressing gene expression. Hypermethylation
of tumor suppressor gene promoter regions may result in their inactivation,
thereby fostering the development of cancer. In contrast, hypomethylation
at particular genomic regions can result in oncogene activation or genomic
instability (Kulis et al., 2010). Histones are proteins that DNA wraps around
and forms a structure called chromatin. Various chemical modifications such
as methylation, acetylation, phosphorylation and ubiquitination can occur
in histone proteins. These modifications can regulate gene expression by
altering the DNA’s accessibility to transcriptional machinery. For instance,
acetylation of histones is generally associated with gene activation, whereas
methylation may be associated with either gene activation or suppression,
depending on the site and degree of methylation. Frequently observed
in cancer, abnormal histone modifications cause dysregulation of gene
expression and promote tumor growth and progression (Zhao et al., 2019). Non-coding RNAs such as microRNAs (miRNAs) and long non-coding
RNAs (lncRNAs) are emerging as crucial players in epigenetic regulation. miRNAs can bind to messenger RNAs (mRNAs) and block their translation
or regulate gene expression by promoting their degradation. Deregulated
expression of miRNAs has been implicated in a variety of cancers. On the
other hand, lncRNAs can interact with DNA, RNA and proteins by affecting
gene expression and chromatin organization. Altered expression of specific
lncRNAs has been associated with cancer development and progression
(Morlando et al., 2018). Chromatin remodeling complexes can alter the
structure and accessibility of chromatin by affecting gene expression. These
complexes use energy to reposition, remove or replace histones, allowing for
changes in gene accessibility and transcriptional regulation. Dysregulation miRNAs can bind to messenger RNAs (mRNAs) and block their translation
or regulate gene expression by promoting their degradation. Deregulated
expression of miRNAs has been implicated in a variety of cancers. On the
other hand, lncRNAs can interact with DNA, RNA and proteins by affecting
gene expression and chromatin organization. 6. Epigenetic Changes Altered expression of specific
lncRNAs has been associated with cancer development and progression
(Morlando et al., 2018). Chromatin remodeling complexes can alter the
structure and accessibility of chromatin by affecting gene expression. These
complexes use energy to reposition, remove or replace histones, allowing for
changes in gene accessibility and transcriptional regulation. Dysregulation The Impact of Biochemical Alterations in the Tumor Microenvironment on Cancer... 96 of chromatin remodeling complexes can lead to abnormal gene expression
patterns and contribute to cancer development (Längst et al., 2015). Conclusion Biochemical changes in the tumor microenvironment can affect cancer
cell metabolism. Hypoxia, a common feature of solid tumors, leads to
altered metabolic pathways, including increased glycolysis and dependence
on alternative energy sources. These metabolic adaptations provide survival
advantages to cancer cells and support their growth and proliferation. Understanding the effects of biochemical changes in the tumor
microenvironment is crucial to developing effective cancer treatments. Targeting specific components and signaling pathways within the
microenvironment has the potential to improve treatment outcomes by
inhibiting tumor growth, overcoming therapy resistance, and enhancing
anti-tumor immune responses. Treatments that modulate the tumor
microenvironment, such as immunotherapies and anti-angiogenic agents,
are being actively explored as promising strategies in cancer therapy. Seyhan Turk | 97 References 1. Arneth B. Tumor Microenvironment. Medicina. 2020;56(1):15. 2. Denton AE, Roberts EW, Fearon DT. Stromal Cells in the Tumor Mic-
roenvironment. In: Owens BMJ, Lakins MA, editors. Stromal Immuno-
logy. Cham: Springer International Publishing; 2018. p. 99-114. 3. Wu AA, Drake V, Huang HS, Chiu S, Zheng L. Reprogramming the tu-
mor microenvironment: tumor-induced immunosuppressive factors pa-
ralyze T cells. Oncoimmunology. 2015;4(7):e1016700. 4. Multhoff G, Vaupel P. Radiation-induced changes in microcirculation and
interstitial fluid pressure affecting the delivery of macromolecules and na-
notherapeutics to tumors. Frontiers in Oncology. 2012;2. 5. Hinshaw DC, Shevde LA. The Tumor Microenvironment Innately Mo-
dulates Cancer Progression. Cancer Research. 2019;79(18):4557-66. 6. Fukumura D, Jain RK. Tumor microvasculature and microenvironment:
Targets for anti-angiogenesis and normalization. Microvascular Research. 2007;74(2):72-84. 7. Nicosia RF. What Is the Role of Vascular Endothelial Growth Factor-Re-
lated Molecules in Tumor Angiogenesis? The American Journal of Patho-
logy. 1998;153(1):11-6. 8. Byrne AM, Bouchier-Hayes DJ, Harmey JH. Angiogenic and cell survi-
val functions of Vascular Endothelial Growth Factor (VEGF). Journal of
Cellular and Molecular Medicine. 2005;9(4):777-94. 9. Feldman SR, Yaar M. Oncogenes: The Growth Control Genes. Archives
of Dermatology. 1991;127(5):707-11. 10. Jones RG, Thompson CB. Tumor suppressors and cell metabolism: a re-
cipe for cancer growth. Genes Dev. 2009;23(5):537-48. 11. Ryan KM, Phillips AC, Vousden KH. Regulation and function of
the p53 tumor suppressor protein. Current Opinion in Cell Biology. 2001;13(3):332-7. 12. Müller R. Proto-oncogenes and differentiation. Trends in Biochemical
Sciences. 1986;11(3):129-32. 13. Jan R, Chaudhry GE. Understanding Apoptosis and Apoptotic Pathways
Targeted Cancer Therapeutics. Adv Pharm Bull. 2019;9(2):205-18. 14. Abel EL, Angel JM, Kiguchi K, DiGiovanni J. Multi-stage chemical car-
cinogenesis in mouse skin: Fundamentals and applications. Nature Pro-
tocols. 2009;4(9):1350-62. 15. Bataille P, Reynard A, Ducarme G. Spontaneous heterotopic triplets - A
review of literature. J Gynecol Obstet Hum Reprod. 2017;46(8):657-9. 16. Kurebayashi J. Biological and clinical significance of HER2 overexpressi-
on in breast cancer. Breast Cancer. 2001;8(1):45-51. 98 | The Impact of Biochemical Alterations in the Tumor Microenvironment on Cancer... 98 17. Klinakis A, Szabolcs M, Politi K, Kiaris H, Artavanis-Tsakonas S, Efstra-
tiadis A. Myc is a Notch1 transcriptional target and a requisite for Not-
ch1-induced mammary tumorigenesis in mice. Proc Natl Acad Sci U S A. 2006;103(24):9262-7. 18. Lee EY, Muller WJ. Oncogenes and tumor suppressor genes. Cold Spring
Harb Perspect Biol. 2010;2(10):a003236. 19. Quatrin M, Pasti C, Romano S, Iarossi B, Giménez V, Schuttenberg V,
et al. References A new dual translocation of chromosome 14 in a pediatric Bur-
kitt lymphoma/leukemia patient: t(8;14) and t(14;15). Cancer Genetics. 2021;258-259:131-4. 20. Lüscher B, Vervoorts J. Regulation of gene transcription by the oncopro-
tein MYC. Gene. 2012;494(2):145-60. 21. Nie Z, Hu G, Wei G, Cui K, Yamane A, Resch W, et al. c-Myc Is a
Universal Amplifier of Expressed Genes in Lymphocytes and Embryonic
Stem Cells. Cell. 2012;151(1):68-79. 22. Rohrberg J, Van de Mark D, Amouzgar M, Lee JV, Taileb M, Corella A,
et al. MYC Dysregulates Mitosis, Revealing Cancer Vulnerabilities. Cell
Reports. 2020;30(10):3368-82.e7. 23. Miyakura Y, Sugano K, Fukayama N, Konishi F, Nagai H. Concurrent
Mutations of K-ras Oncogene at Codons 12 and 22 in Colon Cancer. Ja-
panese Journal of Clinical Oncology. 2002;32(6):219-21. 24. Gerber M, Goel S, Maitra R. In silico comparative analysis of KRAS mu-
tations at codons 12 and 13: Structural modifications of P-Loop, switch
I&II regions preventing GTP hydrolysis. Computers in Biology and Me-
dicine. 2022;141:105110. 25. Farr CJ, Saiki RK, Erlich HA, McCormick F, Marshall CJ. Analysis of
RAS gene mutations in acute myeloid leukemia by polymerase chain rea-
ction and oligonucleotide probes. Proceedings of the National Academy
of Sciences. 1988;85(5):1629-33. 26. Sparmann A, Bar-Sagi D. Ras-induced interleukin-8 expression
plays a critical role in tumor growth and angiogenesis. Cancer Cell. 2004;6(5):447-58. 27. David R, Lamki N, Fan S, Singleton EB, Eftekhari F, Shirkhoda A, et al. The many faces of neuroblastoma. RadioGraphics. 1989;9(5):859-82. 28. Hatzi E, Murphy C, Zoephel A, Ahorn H, Tontsch U, Bamberger
A-M, et al. N-myc oncogene overexpression down-regulates leukemia
inhibitory factor in neuroblastoma. European Journal of Biochemistry. 2002;269(15):3732-41. 29. Nisar S, Hashem S, Macha AM, Yadav KS, Muralitharan S, Therachiyil
L, et al. Exploring Dysregulated Signaling Pathways in Cancer. Current
Pharmaceutical Design. 2020;26(4):429-45. rk | 99 n Turk | 99 99 Seyhan Turk Seyhan Turk 30. Sahu S, Singh B, Rai AK. Human endogenous retrovirus regulates
the initiation and progression of cancers (Review). Mol Clin Oncol. 2022;17(4):143. 31. Romanish MT, Cohen CJ, Mager DL. Potential mechanisms of endoge-
nous retroviral-mediated genomic instability in human cancer. Seminars
in Cancer Biology. 2010;20(4):246-53. 32. Fan H. Retroviruses and Their Role in Cancer. In: Levy JA, editor. The
Retroviridae. Boston, MA: Springer US; 1994. p. 313-62. 33. Grandér D. How do mutated oncogenes and tumor suppressor genes
cause cancer? Medical Oncology. 1998;15(1):20-6. 34. Aranda-Anzaldo
A. References Cancer
Development
and
Progression:
A
Non-Adaptive Process Driven by Genetic Drift. Acta Biotheoretica. 2001;49(2):89-108. 35. Temko D, Tomlinson IPM, Severini S, Schuster-Böckler B, Graham TA. The effects of mutational processes and selection on driver mutations ac-
ross cancer types. Nature Communications. 2018;9(1):1857. 36. Li X. Dynamic changes of driver genes’ mutations across clinical stages in
nine cancer types. Cancer Medicine. 2016;5(7):1556-65. 37. Bozic I, Gerold JM, Nowak MA. Quantifying Clonal and Subclonal Pas-
senger Mutations in Cancer Evolution. PLOS Computational Biology. 2016;12(2):e1004731. 38. Iau PTC, Macmillan RD, Blamey RW. Germ line mutations associ-
ated with breast cancer susceptibility. European Journal of Cancer. 2001;37(3):300-21. 39. Martincorena I, Campbell PJ. Somatic mutation in cancer and normal
cells. Science. 2015;349(6255):1483-9. 40. Alexandrov LB, Ju YS, Haase K, Van Loo P, Martincorena I, Nik-Zainal
S, et al. Mutational signatures associated with tobacco smoking in human
cancer. Science. 2016;354(6312):618-22. 41. Harvey AJ. Overview of Cell Signaling Pathways in Cancer. In: Badve S,
Kumar GL, editors. Predictive Biomarkers in Oncology: Applications in
Precision Medicine. Cham: Springer International Publishing; 2019. p. 167-82. 42. Lundby A, Franciosa G, Emdal KB, Refsgaard JC, Gnosa SP, Bek-
ker-Jensen DB, et al. Oncogenic Mutations Rewire Signaling Pathways
by Switching Protein Recruitment to Phosphotyrosine Sites. Cell. 2019;179(2):543-60.e26. 43. Yewale C, Baradia D, Vhora I, Patil S, Misra A. Epidermal growth factor
receptor targeting in cancer: A review of trends and strategies. Biomate-
rials. 2013;34(34):8690-707. 100 | The Impact of Biochemical Alterations in the Tumor Microenvironment on Cancer... 44. Martelli AM, Evangelisti C, Chappell W, Abrams SL, Bäsecke J, Sti-
vala F, et al. Targeting the translational apparatus to improve leukemia
therapy: roles of the PI3K/PTEN/Akt/mTOR pathway. Leukemia. 2011;25(7):1064-79. 45. Bian J, Dannappel M, Wan C, Firestein R. Transcriptional Regulation of
Wnt/β-Catenin Pathway in Colorectal Cancer. Cells. 2020;9(9):2125. 46. Yin L, Velazquez OC, Liu Z-J. Notch signaling: Emerging molecular tar-
gets for cancer therapy. Biochemical Pharmacology. 2010;80(5):690-701. 47. Skoda AM, Simovic D, Karin V, Kardum V, Vranic S, Serman L. The role
of the Hedgehog signaling pathway in cancer: A comprehensive review. Biomolecules and Biomedicine. 2018;18(1):8-20. 48. Lincet H, Icard P. How do glycolytic enzymes favour cancer cell prolife-
ration by nonmetabolic functions? Oncogene. 2015;34(29):3751-9. 49. Desideri E, Ciriolo MR. Glutamine Addiction of Cancer Cells. In: Ra-
jendram R, Preedy VR, Patel VB, editors. Glutamine in Clinical Nutriti-
on. New York, NY: Springer New York; 2015. p. 99-111. 50. 1
Prof. Dr., Department of Physiology, Faculty of Medicine, Sivas Cumhuriyet University,
eozdemir3368@gmail.com, eozdemir@cumhuriyet.edu.tr., ORCID: 0000-0001-8231-1053 Abstract Orexin-A and orexin-B neuropeptides are specifically synthesized and
secreted in hypothalamic neurons. It is known that the orexinergic system
participates in pain modulation as well as its roles in various physiological
processes such as feeding, stress processing, endocrine and cognitive
functions. Orexin ligands activate orexin type-1 (OXR1) and orexin type-2
(OXR2) receptors, each with a different distribution. Orexins are mediators
that play important roles in regulating pain perception at the spinal and
supraspinal levels. These regulatory roles of orexins have been demonstrated
in mechanical, thermal, and chemical models of pain. Periaqueductal gray
(PAG) area of the central nervous system plays an important role in the pain
modulation of orexins. Furthermore, the orexinergic system locus seroleus
(LC) and paragigantocellular lateralis (LPGi) are associated areas and play
an important role in chronic neuropathic pain, stress pain and migraine pain
as well as opioid analgesic activity. In addition, it has been expressed that the
antinociceptive effects of orexins are mediated by endocannabinoids. This
review summarizes studies investigating the antinociceptive effects of orexin
in various types of pain, including migraine, neuropathic pain, visceral and
orofacial pain, and its effects on opioid analgesia and tolerance. Orexinergic System and Antinociception Ercan Özdemir1 Chapter 8
Orexinergic System and Antinociception Chapter 8 Chapter 8 References Robinson AD, Eich M-L, Varambally S. Dysregulation of de novo nuc-
leotide biosynthetic pathway enzymes in cancer and targeting opportuni-
ties. Cancer Letters. 2020;470:134-40. 51. Mashima T, Seimiya H, Tsuruo T. De novo fatty-acid synthesis and rela-
ted pathways as molecular targets for cancer therapy. British Journal of
Cancer. 2009;100(9):1369-72. 52. Alberghina L, Gaglio D, Gelfi C, Moresco R, Mauri G, Bertolazzi P, et
al. Cancer cell growth and survival as a system-level property sustained by
enhanced glycolysis and mitochondrial metabolic remodeling. Frontiers
in Physiology. 2012;3. 53. Vander Heiden MG. Targeting cancer metabolism: a therapeutic window
opens. Nature Reviews Drug Discovery. 2011;10(9):671-84. 54. Carmeliet P, Jain RK. Molecular mechanisms and clinical applications of
angiogenesis. Nature. 2011;473(7347):298-307. 55. Gálvez BG, Matıas-Román S, Albar JP, Sánchez-Madrid F, Arro-
yo AG. Membrane Type 1-Matrix Metalloproteinase Is Activated du-
ring Migration of Human Endothelial Cells and Modulates Endotheli-
al Motility and Matrix Remodeling*. Journal of Biological Chemistry. 2001;276(40):37491-500. 56. Payne SJ, Jones L. Influence of the tumor microenvironment on angioge-
nesis. Future Oncology. 2011;7(3):395-408. 57. Petrovic N. Targeting Angiogenesis in Cancer Treatments: Whe-
re do we Stand? Journal of Pharmacy & Pharmaceutical Sciences. 2016;19(2):226-38. Seyhan Turk | 101 101 Seyhan Turk | 101 58. Zheng YG, Wu J, Chen Z, Goodman M. Chemical regulation of epi-
genetic modifications: Opportunities for new cancer therapy. Medicinal
Research Reviews. 2008;28(5):645-87. 59. Kulis M, Esteller M. 2 - DNA Methylation and Cancer. In: Herceg Z,
Ushijima T, editors. Advances in Genetics. 70: Academic Press; 2010. p. 27-56. 60. Zhao Z, Shilatifard A. Epigenetic modifications of histones in cancer. Genome Biology. 2019;20(1):245. 61. Morlando M, Fatica A. Alteration of Epigenetic Regulation by Long
Noncoding RNAs in Cancer. International Journal of Molecular Scien-
ces. 2018;19(2):570. 62. Längst G, Manelyte L. Chromatin Remodelers: From Function to Dys-
function. Genes. 2015;6(2):299-324. 1. Introduction Orexin-A and orexin-B neuropeptides that make up the orexin (hypocretin)
system are produced by enzymatic reactions from prepro-orexin in the
lateral hypothalamus. Each of these neuropeptides exert their effects via two
G-protein coupled receptors (GPCR) called orexin-1 (OX1) and orexin-2
(OX2). Orexin-A activates both OX1 and OX2 receptors with similar affinity,
while orexin-B activates only OX2 receptors (1). https://doi.org/10.58830/ozgur.pub128.c688 https://doi.org/10.58830/ozgur.pub128.c688 103 104 Orexinergic System and Antinociception Orexinergic neurons are located especially in the dorsal medial
hypothalamus, perifornical area, and lateral parts of the lateral hypothalamus
(2, 3). These neuropeptides have been reported to be involved in a wide variety
of physiological functions such as arousal (4), feeding (2), neuroendocrine
processes (5), and autonomic control (6). There are two types of G-protein
coupled receptors for orexin ligands that are distributed differently in the
central nervous system (7). These receptors are orexin type-1 (OX1R)
and orexin type-2 receptors. OX1R is selective for orexin-A, while OX2R
binds both orexin neuropeptides (2). The widespread distribution of orexin
receptors in the central nervous system explains the multifaceted contribution
of the endogenous orexinergic system to homeostatic regulation in the brain
(2). Abundant evidence suggests that both OX1 and OX2 receptors are
expressed on the soma at pre- and post-synaptic terminals, as well as in the
medial and lateral hypothalamic areas (8). Numerous studies have shown that orexins have antinociceptive effects
in the brain and spinal cord in different types of pain, including mechanical
(tail-pressure), thermal (hot-plate, tail-flick, claw-retraction), chemical
(formalin, capsaicin, and abdominal) (9). Orexin receptors can be detected
in many brain structures known to be involved in the transmission of pain
signals (10). It has been reported that Orexin-A exerts antinociceptive effects
in both the brain and spinal cord. In contrast, it is stated that orexin-B has
little antinociceptive effect (11). The periaqueductal gray (PAG) area in the
central nervous system is an important site in pain regulation by orexins. The analgesic supraspinal mechanism involves retrograde inhibition of
GABA release in the ventrolateral PAG. In addition, orexins interact with
endocannobinoids to produce analgesia (12). The purpose of this section is to elucidate the role of orexin, a hypothalamic
neuropeptide, modulation of pain transmission, opioid analgesia and
tolerance. 2. Mechanisms of Analgesic Effect of Orexin A large body of evidence provides important insights into the possible
mechanisms of orexin’s analgesic action. Orexin increases antinociceptive
activity in the ventral tegmental area (VTA) by activation of orexinergic
receptors in the nucleus accumbens (NAc) in rats (13, 14). Functions
related to nutrition, neuroendocrine functions, sensory information and
nociception are probably formed as a result of mutual interactions of orexins
and neurokinin-1 receptor. This is evidenced by the direct anatomical contact
between orexin-A and neurokinin-1 receptors in the marginal layer of the 105 Ercan Özdemir Ercan Özdemir dorsal horn (15). Another analgesic mechanism of action with Orexin-A
is retrograde inhibition by GABA secretion by increasing the production
of 2-arachidonoylglycerol (2-AG), an endocannabinoid, in the ventrolateral
PAG (16). In addition, a study with orexin-B suggested that activation of
glycinergic and purinergic neurotransmission at the spinal level enhanced
the analgesic effect of orexin (17). 3. Orexinergic System and Neuropathic Pain Orexinergic neurons play an important role in chronic neuropathic pain
as well as stress pain, headache, migraine pain (Table 1). It is a treatment-
resistant chronic pain condition that results from any lesion or disease of the
somatosensory nervous system and has adverse effects on quality of life. The
role of the orexinergic system in neuropathic pain has been demonstrated
in various animal models. The effect of orexin-A on neuropathic pain was
evaluated in rats with neuropathic pain created by sciatic nerve ligation. Orexin-A administered intrathecally 7 days after sciatic nerve injury reduced
the level of mechanical allodynia and neuropathic pain induced by partial
sciatic nerve ligation (18). It reveals that orexins can reduce heat-induced hyperalgesia in rats with
chronic constriction damage to the sciatic nerve. Orexin-A administration
inhibited hyperalgesia caused by sciatic nerve damage, while orexin-A
antiserum antagonizes this effect (19). In addition, orexin-A inhibits Ca2+
flow through the L-type Ca2+ channel in dorsal root ganglion (DRG)
neurons of rat segmental spinal nerve ligation with its effect on high K+-
induced [Ca2+]i increase. This indicates an important effect of orexin for
nociceptive modulation. In addition, nifedipine and lidocaine potently block
high K+-induced depolarization [Ca2+] increase in rats with spinal nerve
ligation (20). Furthermore, neuropharmacological evidence indicates that
OXR2 mediates its inhibitory effects on KCl-induced increases in [Ca2+]i
in C-fiber neurons in a model of sciatic nerve ligation-induced hyperalgesia
in rats (21). In a neuropathic pain model in rats, orexin-A exerts its
antinociception effect through injection of the cholinergic agonist carbachol
and stimulation of the posterior hypothalamus, partially mediated by the
OXR1 in the dorsal horn of the spinal cord (22). Intrathecal administration
of orexin-A to animals significantly reduced the occurrence of mechanical
allodynia experimentally induced by sciatic nerve ligations (18). In addition,
intrathecal administration of orexin-A blocked hyperalgesia, a form of
neuropathic pain, in streptozotocin-induced diabetes mellitus mice (23). Moreover, orexin neurons show that they modulate the sensations of
pain and itching in the opposite direction, namely pain relief and itching Orexinergic System and Antinociception 106 exacerbation (24). In addtion, orexin-A/OX1R signaling has been shown to
play an important role in the prevention of central poststroke pain in mice
through activation of the descending pain control system (25). Table 1. Summary of studies on pain modulation of the orexinergic system
Orexin A/Orexin B OXR1/
OXR2
Pain models
Antinociceptive
activity
Ref. Orexin A/Orexin B
(i.c.v. 3. Orexinergic System and Neuropathic Pain and i.t.)
OXR1/
OXR2
Tail-flick, hot-plate
test, in mice
Enhanced
antinociception
(9)
Orexin A
(i.c.v.)
OXR1
agonist
Tail-flick test, in rats
Inhibitory effects of
pain on RVM
(26)
Orexin A
(intra-PAG
injection)
OXR1
agonist
Formalin test, in rats Decreases nociception
(27)
Orexin A
(intra-LPGi)
OXR1
Formalin test, in rats Decreases nociception
(28)
Orexin A
(i.c.v. and i.t.)
OXR1
Sciatic nerve ligation
(neuropathic pain
model) in rats
Alleviates mechanical
allodynia
(18)
Orexin A (i.v.)
Orexin B (i.v.)
OXR1
OXR2
Model of
trigeminovascular
nociception in rats
Orexin A has
antinociception
Orexin B has no
antinociception
(29)
Orexin A
OXR1
Model of
trigeminovascular
nociception in rats
Inhibit A-fibre
responses to electrical
stimulation
(30)
Orexin A
antagonist
OXR1
(SB-
334867)
Formalin test, in rats Attenuate swim- and
restraint stress-induced
antinociception
(10)
icv, intrcerebroventricularis; it, intratechalis; LPGi, paragigantocellularis lateralis;
RVM, rostral ventral medulla ble 1. Summary of studies on pain modulation of the orexinergic system icv, intrcerebroventricularis; it, intratechalis; LPGi, paragigantocellularis lateralis;
RVM, rostral ventral medulla icv, intrcerebroventricularis; it, intratechalis; LPGi, paragigantocellularis lateralis;
RVM, rostral ventral medulla 4. Orexinergic System and Stress Induced Analgesia The stress-induced analgesic effect is an important form of the defensive
behavioral reaction to fight-or-flight (31). Acute and chronic stress affect the
orexinergic system, causing changes in both pain threshold and nociceptive
behaviors (32). Evidence suggests that chronic stress activates orexin neurons
and thereby inhibits pain transmission In addition, stressful conditions in
experimental animals appear to increase orexin levels, resulting in improved
animal performance and blocking of pain signals (33). Recent evidence has
shown that the interaction between corticotropin-releasing factor (CRF)
and orexinergic neurons may be physiopathologically related to the control 107 Ercan Özdemir Ercan Özdemir of stress-related behaviors. Activation of the orexinergic system modulates
the activity of CRF neurons via OX2R (7). Many evidences suggest that
OX1R responds to both pain and stressful stimuli and is therefore likely to
be involved in stress-induced analgesia (34). During stress, hypothalamic orexin neurons are activated and orexins
are released. Increasing 2-arachidonoylglycerol (2-AG) activates the orexin
receptor type-1 in the lateral PAG, resulting in analgesia. Stress analgesia
has been demonstrated in a mouse model where the orexin and nociceptin/
orphanin FQ systems coordinately regulate nociception (31). In an
experimental study, the paw thermal nociceptive test showed that restraint of
immobilization of the rat increased the pain threshold by 20.5%. Injection of
nociceptin/orphanin into the perifornical area of the lateral hypothalamus in
rats significantly reduced stress-induced analgesia. It has been reported that
the formation of stress-induced analgesia is mediated by direct inhibition of
the orexinergic system in the perifornical area (35). Intracerebroventricular
injection of the selective orexin receptor type-1 antagonist SB 334867
reduced the analgesic effect of restraint stress in the formalin test. Similarly,
blocking of orexin-1 receptors with SB-334867 in rats resulted in a reduction
in antinociceptive behaviors induced by swimming and restraint stress in the
formalin test (10). Therefore, it can be stated that the orexin receptor type-1
mediates an opioid-independent stress-induced analgesia. In one study, prior
administration of the OXR1 antagonist SB 334867 resulted in a reduction
in the antinociceptive effects of restraint stress in animals (36). In addition, another study demonstrated the role of orexin receptors in
antinociception induced by swimming or restraint stress. This study showed
that exposure to 6 minutes of swimming stress combined with 30 minutes of
restraint stress can significantly reduce formalin-induced nociception in rats. The analgesic effect caused by restraint stress or swimming stress was fully
inhibited by the orexin-1 receptor antagonist SB-334867 (10). 5. Orexinergic System and Headache Migraine is defined as a diffuse, chronic, debilitating neurovascular
disorder associated with sensory sensitivity, usually manifested by severe
unilateral headaches. Cluster headache, on the other hand, is a disease
that starts with recurrent unilateral pain attacks, is severe, and is often
associated with autonomic symptoms (37). In general, cluster headache and
migraine are expressed as the two main primary headache disorders. The
basic mechanism in the occurrence of migraine includes the activation of
the trigeminovascular system. Orexin-A prevented electrical stimulation- 108 Orexinergic System and Antinociception induced vasodilation, which was prevented by SB-334867 pretreatment. In
addition, orexin-A blocks the prejunctional release of calcitonin gene-related
peptide (CGRP), which is very important in migraine, from trigeminal
neurons (38). Furthermore, it has been determined that the activation of the
hypothalamus has an important role in the physiopathology of cluster
headache. Cluster headache manifests itself with circadian or seasonal
attacks and shows some features such as changes in hormone levels (37). Orexin neurons are highly organized in the hypothalamus and show broad
projections to areas involved in nociception and autonomic regulation. Given these features of the orexinergic system, orexins are likely to play
an important role in the pathogenesis of cluster headache and migraine. Injection of orexin-A into the posterior hypothalamic region of the rat
reduces A- and C-fiber type nerve responses to dural electrical stimulation
in the trigeminal nucleus caudalis and harmful thermal stimulation of the
facial receptive field (39). Intravenous administration of orexin-A has been
shown to inhibit neurogenic dural vasodilation through OXR1 activation. This effect acts on the trigeminovascular system, causing partial blocking
of calcitonin gene-related peptide (CGRP) release (29). In another study,
intravenous injection of orexin-A was shown to block type-A nerve fiber
responses to dural electrical stimulation through activation of OXR1 (30). Although many studies support that the orexinergic system has a very
important role in the pathophysiology of migraine, the results of a clinical
study show that the orexin receptor antagonist fluorexant does not have
sufficient analgesic effect as a potential therapeutic approach in migraine (40). 6. Orexinergic System and Visceral Pain Visceral sensation is one of the main functions of the gastrointestinal
tract and is controlled by the central nervous system. The modulatory
role of orexins secreted from the brain in visceral sense indicates that the
orexinergic system may play a role in the pathophysiology of irritable bowel
syndrome (41). According to a study, intracisternal injection of orexin-A
caused an increase in the threshold volume of the abdominal withdrawal
reflex due to colonic distension. At the same time, the threshold volume
was not changed by the intracisternal OXR1 antagonist SB334867, while
centrally administered SB334867 completely blocked the morphine-induced
analgesic effect against colonic enlargement (42). The results obtained in this
study show that orexin-A can play a modulatory role by being secreted from
the central nervous system to prevent pain caused by colonic distension. 109 Ercan Özdemir Ercan Özdemir Furthermore, dopaminergic signaling pathways have also been found to
play an important role in orexin-induced central analgesic activity against
colonic distension (43). In addition, prior administration of the D1 dopamine
receptor antagonist SCH23390 to animals prevented the analgesic effect
from centrally injected orexin-A for colonic distension (44). Moreover, it
has been demonstrated that the adenosine signaling system also plays an
important role in visceral antinociception regulated by the orexinergic
system. Evidence suggests that subcutaneous administration of theophylline,
an adenosine antagonist, or 1,3-dipropyl-8-cyclopentylxanthine, an
adenosine A1 receptor antagonist, against colonic distension caused by the
centrally injected A1 agonist N(6)-cyclopentyladenosine (CPA) or orexin-A. demonstrated that it inhibits antinociceptive activity (44). 5. The Role of the Orexinergic System on Morphine Analgesia and
Tolerance 5. The Role of the Orexinergic System on Morphine Analgesia and
Tolerance Opioid drugs such as morphine are frequently used in the clinic for the
treatment of chronic and severe pain. On the other hand, long-term use of
these drugs often causes tolerance to analgesic effects (45). There are several
possible explanations for the development of morphine tolerance, including
activation of an intracellular signaling pathway such as nitric oxide (NO)
and mammalian rapamycin target (mTOR), apoptosis in dorsal ganglion
neurons, ghrelin and opioid receptor desensitization, and endocannabinoid
receptor induction (46-49). Numerous studies have shown that OXR1
antagonist administration causes a decrease in the development of morphine-
induced tolerance (50-52) (Table 2). Co-administration of OXR1 antagonist SB-334867 with morphine
inhibits the development of opioid tolerance. Therefore, these data suggest
that OXR1 plays an important role in the development of tolerance to
morphine (51). 110 110 | Orexinergic System and Antinociception Table 2. The role of the orexinergic system on morphine analgesia and tolerance
Orexin A/
Orexin B
OXR1/
OXR2
Pain models
Morphine analgesia
and tolerance
Ref. Orexin A
antagonist
OXR1
antagonist
(SB-334867)
Tail-flick, hot-plate
test, in rats
Attenuates
morphine tolerance
(52)
Orexin A
antagonist
OXR1 blockade
(SB-334867)
The electrical
activity of LC
neurons was studied
using single unit
recording in rats
Prevents morphine
tolerance
(53)
Inhibits
orexin A
secretions
(Yokukansan)
No receptor
blockade
Hot-plate test, in
rats
Attenuates
morphine tolerance
(54)
No effect
OXR1/OXR2
antagonist
suvorexant
Tail-flick test in mice Reduces morphine
tolerance and
dependence
(55)
No effect
OXR1
antagonist
(SB-334867)
The electrical
activity of LC
neurons was studied
using single unit
recording in rats
Attenuates
morphine tolerance
(56)
Orexin B
OXR2
agonist
Tail-flick, hot-plate
test, in rats
Attenuates
morphine tolerance
(52)
No effect
OXR1
antagonist, icv
(SB-334867)
The electrical
activity of LPGi
neurons was studied
using single unit
recording in rats
Prevents morphine
tolerance
(57)
No effect
OXR1
antagonist, icv
(SB-334867
Transparent
cylindrical plexiglas
test chamber, in rats
Decreases naloxone
precipitated
morphine
withdrawal signs. (58)
No effect
OXR1
antagonist, icv
(SB-334867
Transparent
cylindrical plexiglas
test chamber, in rats
Decreases naloxone
precipitated
morphine
withdrawal signs. (59)
No effect
OXR1
antagonist, icv
(SB-334867
The warm-water
tail immersion test,
in rats
Attenuates
morphine tolerance
and dependence
(60)
No effect
OXR1
antagonist, icv
(SB-334867
Tail-flick test, in rats Attenuates
morphine analgesic
tolerance
(51)
icv, intrcerebroventricularis; LC, locus coeruleus; LPGi, paragigantocellularis lateralis 2. 5. The Role of the Orexinergic System on Morphine Analgesia and
Tolerance The role of the orexinergic system on morphine analgesia and tolerance icv, intrcerebroventricularis; LC, locus coeruleus; LPGi, paragigantocellularis lateralis 111 Ercan Özdemir | 11 Ercan Özdemir Ercan Özdemir In addition, orexins play a modulatory role in the analgesic effect of met-
enkephalin in locus coeruleus (LC) neurons. The nucleus locus coeruleus is
one of the important central nervous system regions in the analgesic activity
of opioids and the development of tolerance to morphine. However, they are
detected in high concentrations in LC neurons of the orexin receptor type-1
(61). Spinal administered orexin-A has been shown to reduce mechanical
hyperalgesia caused by repeated intradermal injections of the mu opioid
receptor agonist DAMGO via OX1R (62). Inhibition of OXR1 with SB-
334867 induced a significant alleviation of the development of morphine
dependence and behavioral symptoms induced by naloxone administration
in rats. In addition, long-term blockade of OXR1 may reduce formalin-
induced nociception (63). In one study, intracerebroventricular administration of the OXR1
antagonist SB-334867 to rats demonstrated tolerance to the nociceptive
effect of morphine and a reduction in naloxone-induced withdrawal
symptoms. Therefore, orexins may play a role in morphine analgesic
tolerance and dependence via OXR1 receptors (60). In another study, when
the selective orexin receptor-1 antagonist SB-334867 was administered
to rats in the locus cereleus, morphine reduced analgesic tolerance and
the development of physical dependence (59). In an electrophysiological
study, it was shown that blockade of orexin type-1 receptors prevented
the development of morphine tolerance in the lateral paragigantocellularis
nucleus of rats (57). Similarly, blocking the orexin type-1 receptor in the
lateral paragigantocellularis nucleus in rats has been shown to reduce
naloxone-induced morphine withdrawal symptoms (58). In two studies
at different times, the central inhibition of orexin type-1 receptors with
an OXR1 antagonist showed significant reductions in activation of locus
coeruleus (LC) neurons in morphine-dependent rats with naloxone (56,
64). In an electrophysiological study, it was demonstrated that OX1R
blockade by SB-334867 in rats prevented the development of morphine
tolerance in LC neurons (53). Administration of suvorexant, an OXR1
antagonist, to mice reduces morphine-induced tolerance and dependence. In addition, with repeated administrations, morphine increases tolerance
and dependence in mouse brain through elevation of NMDA, p-ERK and
CREB protein levels. Suvorexant prevents opioid tolerance and addiction
by blocking orexin receptors in the brain and lowering p-ERK and CREB
protein levels (55). 5. The Role of the Orexinergic System on Morphine Analgesia and
Tolerance Bilateral administration of the OX1 receptor antagonist into the nucleus
accumbens (NAc) showed that morphine sensitization acquisition was
reduced, but the OXR2 antagonist produced similar effects only at the 112 Orexinergic System and Antinociception maximal dose. These findings suggest that the OX1 and OX2 receptors are in
the NAc and play a role in acquiring morphine sensitivity (65). Yokukansan,
a traditional herbal (Kampo) drug consisting of seven components, has been
shown to reduce morphine tolerance through inhibition of orexin-A secretion
(54). In an experimental study, it was reported that orexin-A may participate
in the expression of naloxone-induced morphine withdrawal syndrome by
partially reducing the activity of neurons carrying GABAA receptors (66). In addition, co-administration of OX1R antagonist SB-334867 and OX2R
agonist orexin-B with morphine to rats decreased morphine tolerance in tail-
flick and hot-plate antinociceptive tests (52). 6. Conclusion Numerous
evidences
confirm
that
orexinergic
neurons
show
antinociceptive activity at both spinal and supraspinal levels in various types
of pain, such as neuropathic pain, migraine pain, stress pain, and headache. According to the literature, orexin-A shows its antinociceptive activity by
OX1 receptors and this activity is more than orexin-B. Although many
mechanisms have been suggested, the antinociceptive action mechanisms
of orexins have not been fully elucidated. Ventrolateral PAG is an important
site of pain modulation of orexinergic neurons and plays a role in supraspinal
regulation. Retrograde GABA secretion has an important role in this
supraspinal mechanism. In addition, clinical studies investigating the role of
the orexinergic system in pain processing are mostly related to the treatment
of migraine, cluster headache, chronic neuropathic pain, and stress pain. The
results of the studies showed that orexin receptors, especially OXR1, play an
important role in morphine analgesic tolerance and dependence. Ercan Özdemir | 113 113 Ercan Özdemir | 1 References References 1. Boss C, Roch C. Recent trends in orexin research–2010 to 2015. Bioorg Med
Chem Lett. 2015;25:2875–87. 2. Sakurai T, Amemiya A, Ishii M, Matsuzaki I, Chemelli RM, Tanaka, et
al. Orexins and orexin receptors: a family of hypothalamic neuropepti-
des and G protein coupled receptors that regulate feeding behavior. Cell. 1998;92:573-585. 3. Peyron C, Tighe DK, Van Den Pol AN, Lecea L De, Heller HC, Sutcliffe JG,
Kilduff TS. Neurons containing hypocretin (orexin) project to multiple
neuronal systems. J Neurosci. 1998;18:9996-10015. 4. Chemelli RM, Willie JT, Sinton CM, Elmquist JK, Scammell T, Lee C,
et al. Narcolepsy in orexin knockout mice: molecular genetics of sleep
regulation. Cell. 1999;98:437-51. 5. Taylor MM, Samson WK. The other side of the orexins: endocrine and
metabolic actions. Am J Physiol Endocrinol Metab. 2003;284;E13-E17. 5. 6. Date Y, Ueta Y, Yamashita H, Yamaguchi H, Matsukura, S., Kangawa, K.,
et al. Orexins, orexigenic hypothalamic peptides, interact with autono-
mic, neuroendocrine and neuroregulatory systems. Proc Natl Acad Sci. U.S.A. 1999;96:748-753. 7. Marcus J, Aschkenasi C, Lee C. Differential expression of orexin receptors 1
and 2 in the rat brain. J Comp Neurol. 2001;435:6–25. 8. Van den Pol AN, Gao XB, Obrietan K, Kilduff TS, Belousov AB. Pres-
ynaptic and postsynaptic actions and modulation of neuroendocrine
neurons by a new hypothalamic peptide, hypocretin/orexin. J Neurosci. 1998;18:7962-7971. 9. Mobarakeh JI, Takahashi K, Sakurada S, Nishino S, Watanabe H, Kato
M, Yanai K. Enhanced antinociception by intracerebroventricularly and
intrathecally-administered orexin A and B (hypocretin-1 and -2) in mice. Peptides. 2005;26(5):767-77. 9. 10. Heidari-Oranjaghi N, Azhdari-Zarmehri H, Erami E, Haghparast A. An-
tagonism of orexin-1 receptors attenuates swim- and restraint stress-indu-
ced antinociceptive behaviors in formalin test. Pharmacol Biochem Be-
hav. 2012;103(2):299-307. 11. Cady RJ, Denson JE, Sullivan LQ, Durham PL. Dual orexin receptor
antagonist 12 inhibits expression of proteins in neurons and glia implicated in
peripheral and central sensitization. Neuroscience. 2014;269:79–92. 12. Razavi BM, Hosseinzadeh H. A review of the role of orexin system in
pain modulation. Biomed Pharmacother. 2017;90:187-193. 13. Haghparast A, Yazdi-Ravandi S, Razavi Y, Haghparast A, Goudarzvand M. Orexin A induced antinociception in the ventral tegmental area involves D1 Orexinergic System and Antinociception and D2 receptors in the nucleus accumbens. Pharmacol Biochem Behav. 2014;126:1–6. 14. Kang X, Tang H, Liu Y, Yuan Y, Wang M. Research progress on the mec-
hanism of orexin in pain regulation in different brain regions. Open Life
Sci. 2021;20;16(1):46-52. 15. References Nazli
M. Immunohistochemi-
cal
localisations
of
orexin-A
and
the
neurokinin
1
receptor in the rat spinal cord. Acta Vet. (Beogr.) 2004;54:311–318. M. 16. Ho YC, Lee HJ, Tung LW, Liao YY, et al. Activation of orexin 1 receptors
in the periaqueductal gray of male rats leads to antinociception via retrog-
rade endocannabinoid (2-arachidonoylglycerol)-induced disinhibition. J
Neurosci. 2011;31:14600–14610. 17. Grudt T, van den Pol A, Perl E. Hypocretin-2 (orexin-B) modulation of
superficial dorsal horn activity in rat. J Physiol. 2002;538:517–525. 18. Yamamoto T, Saito O, Shono K, Aoe T, Chiba T. Anti-mechanical allodynic
effect of intrathecal and intracerebroventricular injection of orexin-A in the rat
neuropathic pain model. Neurosci Lett. 2003;347:183–186. 19. Suyama H, Kawamoto M, Shiraishi S, Gaus S, Kajiyama S, Yuge O. Analgesic
effect of intrathecal administration of orexin on neuropathic pain in rats. In
Vivo. 2004,18:119–124. 20. Kimura
M,
Ishikawa
M,
Kawai
Y,
Shibuta-
ni
K,
Uchida
R,
Eguchi
Y,
Kuboyama
N. Effects of lidocaine and orexin on [Ca2+]i in dosal root ganglion
neuron of rat segmental spinal nerve ligation model. Japan Pharmacol Ther. 2014;42:723–734. 21 21. Yamaguchi M, Ishikawa M, Aono Y, Saigusa T. OX2 receptors mediate
the inhibitory effects of orexin-A on potassium chloride-induced incre-
ases in intracellular calcium ion levels in neurons derived from rat dor-
sal root ganglion in a chronic pain model. Neuropsychopharmacol Rep. 2020;40(1):30-38. 22. Jeong Y, Holden J. The role of spinal orexin-1 receptors in posterior
hypothalamic
modulation
of
neuropathic
pain. Neuroscience. 2009;159:1414–1421. 23. Kajiyama S, Kawamoto M, Shiraishi S, Gaus S, Matsunaga A, Suyama
H, et al. Spinal orexin-1 receptors mediate anti-hyperalgesic effects of int-
rathecally-administered orexins in diabetic neuropathic pain model rats. Brain Res. 2005;1044(1):76–86. 24. Kaneko T, Kuwaki T, Kashiwadani H. Hypothalamic orexinergic neurons
modulate pain and itch in an opposite way: pain relief and itch exacerba-
tion. J Physiol Sci. 2022;22;72(1):21. 115 Ercan Özdemir 25. Matsuura W, Nakamoto K, Tokuyama S. Involvement of descending pain
control system regulated by orexin receptor signaling in the induction of
central post-stroke pain in mice. Eur J Pharmacol. 2020;874:173029. 26. Azhdari-Zarmehri H, Semnanian S, Fathollahi Y, Pakdel FG. Tail flick
modification of orexin-a induced changes of electrophysiological para-
meters in the rostral ventromedial medulla. Cell J. 2014;16(2):131-40. 27. Azhdari Zarmehri H, Semnanian S, Fathollahi Y, Erami E, Khakpay R,
Azizi H, Rohampour K. Intra-periaqueductal gray matter microinjecti-
on of orexin-A decreases formalin-induced nociceptive behaviors in adult
male rats. J Pain. 2011;12(2):280-7. 28. Erami E, Azhdari-Zarmehri H, Ghasemi-Dashkhasan E, Esmaeili MH,
Semnanian S. M. Intra-paragigantocellularis lateralis injection of orexin-A
has an antinociceptive effect on hot plate and formalin tests in rat. Brain
Res. 2012a;1478:16-23. 29. Holland P, Akerman S, Goadsby P. Orexin 1 receptor activation attenuates
neurogenic dural vasodilation in an animal model of trigeminovascular
nociception. J Pharmacol Exp Ther. 2005;315:1380–1385. 30. Holland P, Akerman S, Goadsby P. Modulation of nociceptive dural input to
the trigeminal nucleus caudalis via activation of the orexin 1 receptor in the
rat. Eur J Neurosci. 2006;24:2825–2833. 31. Xie X, Wisor J, Hara J, Crowder T, LeWinter R, Khroyan T. Hypocretin/orexin
and nociceptin/orphanin FQ coordinately regulate analgesia in a mouse model
of stress-induced analgesia. J Clin Invest. 2008;118:2471–2481. 32. Azhdari-Zarmehri H, Mohammad-Zadeh M, Shabani M. The role of
hypocretin/orexin in stress-induced analgesia, J. Kerman Uni Med Sci. 2015;22:205–17. 33. Watanabe S, Kuwaki T, Yanagisawa M, Fukuda Y, Shimoyama M. Persistent
pain and stress activate pain-inhibitory orexin pathways. NeuroReport. 2005;16:5–8. 34. Sofi-Abadi M, Heidari-Oranjaghi N, Ghasemi E, Esmaeili MH, Hagh-
doost-Yazdi H, Erami E, et al. Assesment of orexin receptor 1 in stress
attenuated nociceptive behaviours in formalin test. Physiol Pharmacol
2011;12:188–93. 35. Gerashchenko D, Horvath TL, Xie X. Direct inhibition of hypocretin/orexin
neurons in the lateral hypothalamus by nociceptin/orphanin FQ blocks
stress induced analgesia in rats. Neuropharmacology. 2011;60:543–549. 36. Bonaventure P, Yun S, Johnson PL, Shekhar A, Fitz SD, Shireman
BT, et al. A selective orexin-1 receptor antagonist attenuates stress-in-
duced hyperarousal without hypnotic effects. J Pharmacol Exp Ther. 2015;352(3):590-601. 116 | Orexinergic System and Antinociception 37. Holland P, Goadsby P. Cluster headache hypothalamus, and orexin. Curr Pain
Headache Rep. 2009;13:147–154. 38. Roohbakhsh A, Alavi MS, Azhdari-Zarmehri H. The orexinergic (hy-
pocretin) system and nociception: An update to supraspinal mechanisms. Curr Med Chem. 2018;25(32):3917-3929. 39. Bartsch T, Levy MJ, Knight YE, Goadsby PJ. Differential modulation of
nociceptive dural input to [hypocretin] orexin A and B receptor activation in
the posterior hypothalamic area. Pain 2004;109:367–78. 40. Chabi A, Zhang Y, Jackson S, Cady R, Lines C, Herring WJ, Connor KM,
Michelson D. Randomized controlled trial of the orexin receptor antagonist
filorexant for migraine prophylaxis. Cephalalgia 2015;35:379–388. 41. Longstreth GF, Thompson WG, Chey WD, Houghton LA, Mearin F,
Spiller
RC. Functional
bowel
disorders,
Gastroenterology. 2006;130:1480–1491. 42. Okumura T, Nozu T, Kumei S, Takakusaki K, Miyagishi S, Ohhira M. Antinociceptive action against colonic distension by brain orexin in conscious
rats. Brain Res. 2014;1598:12–17. 43. M. Okumura T, Nozu T, Kumei S, Takakusaki K, Miyagishi S, Ohhira M. Involvement of the dopaminergic system in the central orexin-induced
antinociceptive action against colonic distension in conscious rats. Neurosci
Lett. 2015;605:34–38. 44. Okumura T, Nozu T, Kumei S, Takakusaki K, Miyagishi S, Ohhira M. Adenosine A1 receptors mediate the intracisternal injection of orexin-induced
antinociceptive action against colonic distension in conscious rats. J Neurol
Sci. 2016;15:106–110. 45. Andrade AG, Vandermaelen R. Morphine tolerance and dependence in the
locus coeruleus: single cell studies in brain slices. Eur J Pharmacol. 1983;91:161–69. 46. Ozdemir E, Bagcivan I, Durmus N, Altun A, Gursoy S. The nitric oxi-
de-cGMP signaling pathway plays a significant role in tolerance to the anal-
gesic effect of morphine. Can J Physiol Pharmacol. 2011;89(2):89-95. 47. Baser T, Ozdemir E, Filiz AK, Taskiran AS, Gursoy S. Ghrelin recep-
tor agonist hexarelin attenuates antinociceptive tolerance to morphine in
rats. Can J Physiol Pharmacol. 2021;99(5):461-467. 48. Avci O, Ozdemir E, Taskiran AS, Inan ZDS, Gursoy S. Metformin pre-
vents morphine-induced apoptosis in rats with diabetic neuropathy: a
possible mechanism for attenuating morphine tolerance. Naunyn Sch-
miedebergs Arch Pharmacol. 2022;395(11):1449-1462. 49. Ozdemir E. The role of the cannabinoid system in opioid analgesia and
tolerance. Mini Rev Med Chem. 2020;20(10):875-885. 117 Ercan Özdemir Ercan Özdemir 50. Nazemi S, Azhdari-Zarmehri H, Haghdoost-Yazdi H. Role of orexin in the
tolerance and physical dependence to morphine. J Babol Univ Med Sci. 2014;16:54–61. 51. Ranjbar-Slamloo Y, Azizi H, Fathollahi Y, Semnanian S. Orexin recep-
tor type-1 antagonist SB-334867 inhibits the development of morphine
analgesic tolerance in rats. Peptides. 2012;56–59. 52. Ozdemir E, Baser T, Taskiran AS. Blockade of orexin receptor type-1 by
SB-334867 and activation of orexin receptor type-2 attenuate morphine
tolerance in rats. Physiol Int. 2022;109(4):457-474. 53. Abdollahi H, Ghaemi-Jandabi M, Azizi H, Semnanian S. The role of
orexin type-1 receptors in the development of morphine tolerance in lo-
cus coeruleus neurons: An electrophysiological perspective. Brain Res. 2016;1646:91-97. 54. Katayama A, Kanada Y, Tsukada M, Akanuma Y, Takemura H, Ono T,
Suga H, Mera H, Hisamitsu T, Sunagawa M. Yokukansan (Kampo me-
dicinal formula) prevents the development of morphine tolerance by in-
hibiting the secretion of orexin A. Integr Med Res. 2018;7(2):141-148. 55. Esmaili-Shahzade-Ali-Akbari P, Hosseinzadeh H, Mehri S. Effect of suvo-
rexant on morphine tolerance and dependence in mice: Role of NMDA,
AMPA, ERK and CREB proteins. Neurotoxicology. 2021;84:64-72. 56. Fakhari M, Azizi H, Semnanian S. M. Central antagonism of orexin type-1
receptors attenuates the development of morphine dependence in rat lo-
cus coeruleus neurons. Neuroscience. 2017;363:1-10. 57. Ghaemi-Jandabi M, Azizi H, Semnanian S. Blockade of orexin type 1
receptors inhibits the development of morphine tolerance in lateral pa-
ragigantocellularis nucleus: an electrophysiological approach. Brain Res. 2014;1578:14-22. 58. Ahmadi-Soleimani SM, Ghaemi-Jandabi M, Azizi H, Semnanian S. Orexin type 1 receptor antagonism in lateral paragigantocellularis nuc-
leus attenuates naloxone precipitated morphine withdrawal symptoms in
rats. Neurosci Lett. 2014;558:62-6. 59. Mousavi Y, Azizi H, Mirnajafi-Zadeh J, Javan M, Semnanian S. Blockade
of orexin type-1 receptors in locus coeruleus nucleus attenuates the deve-
lopment of morphine dependency in rats. Neurosci Lett. 2014;578:90-4. 60. Erami E, Azhdari-Zarmehri H, Rahmani A, Ghasemi-Dashkhasan E,
Semnanian S, Haghparast A. Blockade of orexin receptor 1 attenuates
the development of morphine tolerance and physical dependence in rats. Pharmacol Biochem Behav. 2012b;103(2):212-9. 61. Mohammad Ahmadi Soleimani S, Azizi H, Mirnajafi-Zadeh J, Semnanian S. Orexin type 1 receptor antagonism in rat locus coeruleus prevents the 118 Orexinergic System and Antinociception analgesic effect of intra-LC met-enkephalin microinjection. Pharmacol
Biochem Behav. 2015;136:102–106. analgesic effect of intra-LC met-enkephalin microinjection. Pharmacol
Biochem Behav. 2015;136:102–106. 62. 62. Youn DH, Jun J, Kim TW, Park K. Spinal orexin A attenuates opio-
id-induced mechanical hypersensitivity in the rat. Korean J Pain. 2022;35(4):433-439. 63. Kourosh-Arami M, Joghataei MT, Komaki A, Gholami M, Najafi Z,
Lavaie M. Persistent effects of the orexin-1 receptor antagonist SB-
334867 on naloxone precipitated morphine withdrawal symptoms
and nociceptive behaviors in morphine dependent rats. Int J Neurosci. 2022;132(1):67-76. 64. Aghajani N, Pourhamzeh M, Azizi H, Semnanian S. Central blocka-
de of orexin type 1 receptors reduces naloxone induced activation of
locus coeruleus neurons in morphine dependent rats. Neurosci Lett. 2021;755:135909. 64. 65. Assar N, Mahmoudi D, Mousavi Z, Zarrabian S, Haghparast A. Role of
orexin-1 and -2 receptors within the nucleus accumbens in the acquisition
of sensitization to morphine in rats. Behav Brain Res. 2019;373:112090. 66. 66. Davoudi M, Azizi H, Mirnajafi-Zadeh J, Semnanian S. The blockade of
GABAA receptors attenuates the inhibitory effect of orexin type 1 recep-
tors antagonist on morphine withdrawal syndrome in rats. Neurosci Lett. 2016;617:201-6. Chapter 9 Advancing Medical Frontiers: Unveiling the
Potential of Artificial Placenta in Perinatal
Medicine Rauf Melekoğlu1
Ayşe Şebnem Erenler2 1
Inonu University, Faculty of Medicine, Department of Obstetrics and Gynecology,
44280,Malatya, TURKİYE, rauf.melekoglu@inonu.edu.tr, ORCID:https://orcid.org/0000-
0001-7113-6691 2
Malatya Turgut Ozal University, Faculty of Medicine, Department of Medical Biology,44210,
Malatya, TURKİYE, serenler44@gmail.com, ORCID:https://orcid.org/ 0000-0002-1786-
5022 1
Inonu University, Faculty of Medicine, Department of Obstetrics and Gynecology,
44280,Malatya, TURKİYE, rauf.melekoglu@inonu.edu.tr, ORCID:https://orcid.org/0000-
0001-7113-6691
2
Malatya Turgut Ozal University, Faculty of Medicine, Department of Medical Biology,44210,
Malatya, TURKİYE, serenler44@gmail.com, ORCID:https://orcid.org/ 0000-0002-1786-
5022 Abstract Advancements in medical technology have led to the development of artificial
placenta systems, which aim to support the survival and development of
extremely premature infants. The placenta plays a vital role in fetal development
by facilitating nutrient exchange and waste removal. Premature birth poses
significant challenges in neonatal care, with preterm infants facing increased
risks of morbidity and mortality. Respiratory failure is a major concern due
to the underdeveloped lungs of preterm infants. Artificial placenta models
have been designed to mimic fetal and utero-placental physiology, offering
potential solutions to these challenges. This abstract reviews the history and components of artificial placenta systems,
highlighting the importance of pumpless arterio-venous (AV) circuits, low-
resistance oxygenators, umbilical access, and immersion in sterile fluid. The development of these components has led to improved survival rates
and stability in experimental models. However, challenges such as cardiac
afterload, optimization of circuit design, and prevention of infection and
inflammation remain to be addressed. Promising artificial placenta models have been developed by research groups
at the University of Michigan, Tohoku University (Sendai, Japan), and the
University of Western Australia (Perth). These models have demonstrated https://doi.org/10.58830/ozgur.pub128.c689 https://doi.org/10.58830/ozgur.pub128.c689 119 120 Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... increased survival times, stable hemodynamics, and successful organ
maturation. The Philadelphia Children’s Hospital model, known as EXTEND
AW, has shown particular success, with lambs surviving up to 28 days and
exhibiting normal organ development and neurological maturation. Despite these advancements, there are still challenges to overcome before
artificial placenta technology can be implemented in clinical practice. These
include reducing oxygenator surface area, improving hemocompatibility,
optimizing nutrition and amniotic fluid composition, standardizing patient
selection criteria, and developing efficient cannulation techniques. In conclusion, artificial placenta technology is a promising field with the
potential to revolutionize neonatal care. With further advancements and
research, artificial placenta systems may offer a solution to the challenges
faced by extremely premature infants, improving their chances of survival and
long-term health outcomes. Fetal and placental anatomy The human gestation period, ranging approximately 266 days or thirty-
eight weeks from fertilization to delivery, is a remarkable process of prenatal
development. During the early stages of pregnancy, the embryonic period
unfolds, encompassing the formation of crucial organ systems that lay the
foundation for the growing individual. This period concludes at the end of
the eighth week, marking the transition into the fetal period. Throughout
the remainder of pregnancy, the focus shifts towards the maturation of
organ systems and overall growth (Fig 1). The placenta, a complex and
highly specialized organ composed of both embryonic/fetal and maternal
components, plays a pivotal role in supporting the developing fetus. It serves
as a nexus for nutrient exchange, providing essential sustenance for fetal
development, while also facilitating the removal of metabolic waste products. The intricate interplay between the embryo/fetus and the maternal organism
through the placenta ensures the survival and thriving of the growing life
within the womb (1). 121 Rauf Melekoğlu / Ayşe Şebnem Erenler Figure 1. A depiction of the various embryonic and fetal stages during intrauterine
development (2). Figure 1. A depiction of the various embryonic and fetal stages during intrauterine
development (2). Placenta The placenta is a remarkable fetomaternal organ that plays a critical role
in supporting the developing fetus throughout pregnancy. It consists of two
distinct components: the fetal part, which originates from the chorionic sac
(chorion frondosum), and the maternal part, derived from the endometrium
(decidua basalis). Together, the placenta and the umbilical cord form a
sophisticated transport system, facilitating the exchange of substances
between the mother and the fetus (3). The placenta serves multiple essential functions, ensuring the well-being
and development of the growing fetus: Protection: The placenta acts as a protective barrier, shielding the fetus
from potentially harmful substances and pathogens present in the maternal
circulation. Nutrition: It plays a crucial role in providing the fetus with vital
nutrients, including oxygen, glucose, amino acids, and lipids, necessary for
its growth and development. Respiration: The placenta facilitates the exchange of respiratory gases,
allowing the transfer of oxygen from the maternal bloodstream to the fetal
circulation, while carbon dioxide and other waste products are eliminated. 122 | Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... Excretion: Metabolic waste products produced by the fetus, such as
urea and bilirubin, are eliminated through the placenta, preventing their
accumulation and ensuring a stable internal environment. Hormone, Cytokine, and Growth Factor Production: The placenta is
a remarkable endocrine organ, producing a variety of hormones, cytokines,
and growth factors essential for maintaining pregnancy, regulating maternal
physiological adaptations, and supporting fetal development. The intricate functions of the placenta make it a vital interface between
the mother and the developing fetus, enabling the exchange of substances
necessary for growth, metabolism, and overall well-being. Its role extends
far beyond simple nutrient transfer, highlighting its significance in ensuring
a successful and healthy pregnancy (Fig 2). Figure 2. An illustrative depiction showcasing the fetus, placenta, and adjacent
anatomical structures (4). Figure 2. An illustrative depiction showcasing the fetus, placenta, and adjacent
anatomical structures (4). 123 Rauf Melekoğlu / Ayşe Şebnem Erenler Amniotic Fluid: Unveiling Its Significance in Embryonic
Development and Maternal-Fetal Interactions Amniotic Fluid: Unveiling Its Significance in Embryonic
Development and Maternal-Fetal Interactions Amniotic fluid, a clear and yellowish fluid that surrounds and protects
the fetus within the uterus, plays a crucial role in supporting fetal growth,
movement, and development (Fig 3). It serves multiple functions, including
creating space for fetal growth, facilitating absorption of nutrients for growth
and maturation, providing a protective barrier against external trauma, and
exhibiting antibacterial properties due to the presence of cytokines, antibacterial
peptides, and chemokines. Furthermore, amniotic fluid aids in the dilation of
the cervix during delivery, contributing to the birthing process (5). Figure 3. The fetal development stage characterized by the presence of amniotic fluid
surrounding the fetus (6). Figure 3. The fetal development stage characterized by the presence of amniotic fluid
surrounding the fetus (6). Preterm birth Preterm birth, which occurs before 37 weeks of gestation, presents
significant challenges in neonatal care. The nine-month gestation
period is commonly divided into trimesters for convenience. However,
current technology does not support the viability of fetuses born before
approximately 22 weeks of gestation. Survival rates for infants born between
22 and 28 weeks of gestation have improved, but a substantial proportion
still experience significant morbidity that affects their long-term survival. For instance, mortality rates for infants born at 23-25 weeks of gestation
range from 74% to 28%, while morbidity rates range from 92% to 80% (7). | Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... Prematurity, encompassing all newborn babies born before 37 weeks of
gestation, represents a major concern in neonatal health. It is the leading cause
of neonatal death and the most common cause of prenatal hospitalization,
accounting for more than one-third of all infant deaths (7). Prematurity
is associated with a range of complications, including acute respiratory
distress syndrome (RDS), bronchopulmonary dysplasia, periventricular and
intraventricular bleeding, cerebral palsy, retinopathy of prematurity (ROP),
and necrotizing enterocolitis (7). Prematurity- Respiratory stress Respiratory failure poses a significant challenge in the care of very early
preterm newborns due to the impaired gas exchange resulting from the
structural and functional immaturity of their lungs (8). Figure 4. A schematic representation depicting the normal and collapsed alveoli within
the lung of an infant (9). Figure 4. A schematic representation depicting the normal and collapsed alveoli within
the lung of an infant (9). 125 Rauf Melekoğlu / Ayşe Şebnem Erenler The premature initiation of gas ventilation in the lungs hinders lung
development. Extremely premature infants at the limit of viability (22-24
weeks) have lungs in the late canalicular phase of pulmonary development,
characterized by a limited number of fully formed alveoli and a thick
alveolar/capillary interface (Fig 4). At this stage, the underdeveloped
lungs are ill-equipped for efficient gas exchange, leading to respiratory
failure. Additionally, the immaturity of the premature lungs makes them
more susceptible to oxidative stress, infection, and inflammatory damage,
further compromising oxygenation and contributing to the development of
bronchopulmonary dysplasia, a chronic respiratory disease associated with
iatrogenic damage. It is worth noting that despite advancements in neonatal
care, such as minimally invasive neonatal ventilation, exogenous surfactant
administration, and prenatal corticosteroid therapy, these interventions
cannot fully prevent severe respiratory failure due to the structural and
functional immaturity of the premature lungs (10). Understanding the challenges posed by the immature lungs of very early
preterm newborns and their susceptibility to respiratory failure and related
complications is crucial for healthcare professionals in providing optimal
care and developing innovative strategies to improve outcomes for these
vulnerable infants. Artificial Placenta – History and Components The concept of an artificial placenta, which can support the survival and
development of extremely premature infants, has been a topic of fascination
and inspiration in both scientific and fictional Works (Fig 5). Extracorporeal
life support (ECLS) refers to the preservation of life through an external
assist device, while extracorporeal membrane oxygenation (ECMO) involves
the direct transfer of air or oxygen into the blood via a gas-permeable
membrane. The idea of using extracorporeal oxygenation to treat respiratory
failure in severely premature infants emerged shortly after the development
of primitive oxygenator technology in the 1950s (11). Early experiments in the field of artificial placenta research date back
to 1958 when Westin et al. cannulated the umbilical vessels of previable
human fetuses and connected them to a heated perfusion chamber with an
oxygenator, extending their survival for up to 12 hours (12). Subsequent
studies in fetal lambs by Callaghan and colleagues further advanced the
understanding of artificial placenta technology. Over the years, various
research groups have explored different models of artificial placenta, refining
circuit configurations, pumps, oxygenators, vascular access methods, and
fluid containers to improve oxygen delivery and enhance survival rates (13). 126 Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... During the 1970s, advancements in neonatal care, including positive
pressure mechanical ventilation, prenatal maternal steroids, and exogenous
surfactant administration, reduced the focus on artificial placenta research
(14,15). However, the recognition of the limitations of these treatments,
advancements in oxygenator technology in the 1990s, and increased interest
in fetal and utero-placental physiology reignited the exploration of artificial
placenta technology. The research shifted from solely emphasizing long-
term survival to also evaluating safety, fetal well-being, and specific organ
maturation, with the aim of eventual clinical implementation (16). An artificial placenta should encompass several key components to
effectively support fetal development and function. These include: • Maintenance of fetal circulation configuration and open major fetal
shunts to prevent neonatal transmission. • Maintenance of fetal circulation configuration and open major fetal
shunts to prevent neonatal transmission. • Blood oxygenation and maintenance of correct hemoglobin saturation
without lung aeration. • Hemodynamic stability, including appropriate heart rate and blood
pressure responses to fetal conditions. • Proper hydration and elimination of excess fluid to maintain fluid
balance and electrolyte composition. • Adequate kidney function for the elimination of metabolic nitrogenous
wastes. • Endocrine support to ensure the appropriate hormonal environment
for fetal development (17). Artificial Placenta – History and Components Rauf Melekoğlu / Ayşe Şebnem Erenler | 127 Figure 5. Artificial placenta setup: Blood is drained from the right jugular vein using
a collapsible-tubing roller pump and directed to an oxygenator/heat exchanger, after
which it is returned through the umbilical vein. The second umbilical vein is used for
intravenous fluid and medication administration, while an umbilical arterial line is
inserted for hemodynamic monitoring and blood gas sampling. The lamb’s lungs are
kept filled with amniotic fluid by clamping the endotracheal tube. Key anatomical
landmarks include the aorta (Ao), ductus venosus (DV), internal jugular vein (IJV),
inferior vena cava (IVC), right atrium (RA), and superior vena cava (SVC) (18). Figure 5. Artificial placenta setup: Blood is drained from the right jugular vein using
a collapsible-tubing roller pump and directed to an oxygenator/heat exchanger, after
which it is returned through the umbilical vein. The second umbilical vein is used for
intravenous fluid and medication administration, while an umbilical arterial line is
inserted for hemodynamic monitoring and blood gas sampling. The lamb’s lungs are
kept filled with amniotic fluid by clamping the endotracheal tube. Key anatomical
landmarks include the aorta (Ao), ductus venosus (DV), internal jugular vein (IJV),
inferior vena cava (IVC), right atrium (RA), and superior vena cava (SVC) (18). Figure 5. Artificial placenta setup: Blood is drained from the right jugular vein using
a collapsible-tubing roller pump and directed to an oxygenator/heat exchanger, after
which it is returned through the umbilical vein. The second umbilical vein is used for
intravenous fluid and medication administration, while an umbilical arterial line is
inserted for hemodynamic monitoring and blood gas sampling. The lamb’s lungs are
kept filled with amniotic fluid by clamping the endotracheal tube. Key anatomical
landmarks include the aorta (Ao), ductus venosus (DV), internal jugular vein (IJV),
inferior vena cava (IVC), right atrium (RA), and superior vena cava (SVC) (18). | Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... 128 Figure 6. The essential components and key features necessary for the development of an
artificial placenta device (19). Figure 6. The essential components and key features necessary for the development of an
artificial placenta device (19). Pumpless arterio-venous circuit An ideal artificial placental circuit, designed to mimic fetal and utero-
placental physiology, should feature a “pumpless” arterio-venous (AV)
configuration that allows for autoregulation and blood flow driven by
the fetal cardiac beat and arterial pressure as the driving force through the
oxygenator. Early development of artificial placenta technology focused on
AV configurations (20-22). However, early models required the inclusion of pumps to overcome
the high resistance of the oxygenator and achieve physiological fetal flows
(Fig 6). Survival rates in pump-assisted models were systematically limited
due to cardiac decompensation, resulting in circulatory depression and fetal
hydrops. Both centrifugal and roller pumps caused suction that impeded the
natural pumping function of the fetal heart, leading to imbalances in preload
and afterload that strained the cardiac function. The fetal heart is highly 129 Rauf Melekoğlu / Ayşe Şebnem Erenler sensitive to such imbalances, especially in the presence of high-resistance
oxygenators and pumped circuits (23). The umbilical artery (UA) and umbilical vein (UV) configuration
presents challenges due to spasm, and preserving vascular integrity is crucial
in this model. Two main configurations were utilized to connect the fetal
blood vessels to the artificial placental circuit. The arteriovenous (AV)
configuration simulated the natural placenta by using the umbilical vessels,
with fetal blood being pumped by the heart from the umbilical arteries (UA)
to the umbilical vein (UV). The venovenous (VV) configuration involved
connecting the artificial placenta to an oxygenator with the exit through a
catheterized jugular vein and return via the UV. To address load imbalances,
open-top reservoirs were incorporated into the circuit to convert pulsatile
flow to laminar flow and regulate pressure and flows back to the right heart. The addition of reservoirs improved neonatal survival rates in the circuit but
introduced risks of air-blood interaction, increased initial volume, and did
not effectively prevent progressive cardiac decompensation. The inclusion of
a hemodialyzer improved fluid and electrolyte balance and circuit survival
but failed to prevent progressive circulatory failure and was subsequently
disregarded in later versions of the model (24). In pumpless systems, increased
cardiac afterload remained the limiting factor due to supraphysiological
resistance resulting from limitations in oxygenator technology and other
circuit components (25). Further advancements in artificial placenta technology are necessary to
overcome the challenges associated with cardiac afterload and optimize
the circuit’s performance. Pumpless arterio-venous circuit These advancements require improvements in
oxygenator technology and other circuit components to achieve physiological
resistance levels and ensure adequate blood flow, while also addressing issues
related to fluid and electrolyte balance, air-blood interaction, and circuit
stability. Overcoming these challenges will bring us closer to the development
of a functional and effective artificial placenta for supporting the survival and
development of extremely premature infants. Low resistance oxygenators In the early models of artificial placenta, film oxygenators with high surface
area, large feed volume, and high resistance were utilized. These oxygenators
allowed for effective oxygenation through direct blood-air contact but
posed challenges in terms of biological compatibility and increased the
risk of infection (26). To address these concerns, membrane oxygenators
became the new standard in the 1970s. These oxygenators employed flat and Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... 130 helical gas-permeable membranes for gas exchange, eliminating the need for
direct blood-air contact. In recent artificial placenta models, hollow fiber
oxygenators with resistances equivalent to physiological placental resistances
have been implemented, significantly reducing the cardiac afterload required
for pumpless circulation (27). Continuous efforts are being made to further optimize the design of
oxygenators in artificial placenta systems. One approach is to reduce the
surface area and initial volume of the oxygenators. Decreasing the surface
area helps minimize platelet and complement activation, improving
biocompatibility (28). Additionally, researchers are exploring the use of
alternative microfluidic oxygenators, which have the potential to further
reduce feed volumes and enhance the efficiency of gas exchange. These
microfluidic oxygenators hold promise for improving the performance and
compactness of artificial placenta systems (29). By advancing oxygenator technology and exploring innovative designs,
researchers aim to optimize gas exchange efficiency, minimize adverse
reactions, and improve overall compatibility in artificial placenta models. These advancements are crucial for the development of a functional and safe
artificial placenta that can effectively support the survival and development
of extremely premature infants (Fig 7). Figure 7. The implementation of a microfluidic oxygenator for the artificial
placentaconcept, and the arrangement of the experimental setup for in vitro gas
exchange testing (29). Figure 7. The implementation of a microfluidic oxygenator for the artificial
placentaconcept, and the arrangement of the experimental setup for in vitro gas
exchange testing (29). Umbilical access In the pursuit of an ideal artificial placenta model that closely mimics
fetal and utero-placental physiology, the use of umbilical vessels for vascular 131 Rauf Melekoğlu / Ayşe Şebnem Erenler access has been extensively explored. Various configurations utilizing cervical,
femoral, and umbilical vessels have been tested over time. Comparisons have
shown that cannulation of the umbilical artery and umbilical vein (UA/UV)
provides superior flow distribution, particularly to vital organs such as the
heart and brain (30). To optimize flow dynamics, the principles of the Hagen-Poiseuille
law are considered. By using short end-to-end cannulas (approximately 2
cm) and larger umbilical arteries, the resistance within the circuit can be
minimized, allowing for physiological flows in animal models with UA/
UV cannulation (31). The avoidance of cervical vessel cannulation offers
additional advantages, including the protection of important vessels, reduced
risk of embolic events in the brain, and decreased likelihood of complications
related to decannulation, thereby minimizing the need for fetal sedation or
paralysis. However, one of the challenges associated with umbilical vascular
access is vasospasm, which, if severe, can result in circulatory arrest and
subsequent fetal demise (32). To mitigate this risk, humidification of the
umbilical vessels and the administration of vasodilators such as papaverine,
both topically and intravenously, have been proposed (33). To ensure the integrity of the umbilical vessels and prevent trauma, erosion,
turbulence, and obstruction, the use of very short umbilical cannulas that do
not extend deep into the vessels has been recommended. The curvature of
human umbilical vessels makes intra-abdominal advancement of cannulas
impractical (34). In summary, optimizing the vascular access in artificial placenta
models is crucial for ensuring adequate and physiological blood flow
distribution. Cannulation of the umbilical artery and umbilical vein has
shown promising results, although challenges such as vasospasm need to
be addressed for successful implementation. By refining the cannulation
technique and addressing associated complications, researchers aim
to develop an artificial placenta model that effectively supports fetal
circulation and development. Immersion in sterile fluid An important aspect of artificial placental models is the immersion of
the fetus in a sterile and warm liquid environment, typically maintained at
around 39.0°C. This immersion serves several crucial purposes in supporting
fetal development and well-being. Firstly, it provides insulation, protecting
the fetus from external factors such as sound, mechanical pressure, infection,
and injury. Additionally, the presence of amniotic fluid helps regulate the 132 Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... fetus’s body temperature, preventing excessive heat loss or fluid imbalance. It also plays a role in moistening the umbilical vessels and creating a space
that allows for normal fetal breathing and swallowing movements. One significant advantage of keeping the fetal lungs fluid-filled is that
it delays the neonatal hemodynamic transition caused by ventilation. This
helps maintain the integrity of the fetal circulation and supports ongoing
pulmonary development. Ventilation of immature lungs can lead to
complications such as oxygen toxicity, inflammatory damage to delicate lung
tissue, and arrest of lung development. On the other hand, the presence of
fluid in the airways and glottic resistance stimulates pulmonary maturation. Similarly, the presence of amniotic fluid in the gastrointestinal tract has been
shown to enhance the development of the intestinal mucosa and support
overall growth. While the benefits of a liquid immersion environment are evident,
researchers have also acknowledged the potential risks associated with fetal
sepsis in open or semi-closed bath models. Due to their immature immune
systems, fetuses are more vulnerable to bacterial invasion through the lungs
or skin. Infection can trigger a systemic inflammatory response that affects
brain and lung development and often leads to fetal death. To mitigate this
risk, the transition to a closed and sterile environment with continuous
amniotic fluid exchange has been implemented. This approach helps
eliminate pneumonia and reduces the risk of amniotic fluid contamination
and fetal bacteremia, while also minimizing the need for prophylactic
antimicrobials. However, it is important to consider the potential drawbacks of fetal
immersion, such as the physical and potential psychological barrier it
may create between the fetus and prospective parents. The impact of this
distance on parent-fetal bonds is a significant question that requires further
investigation. Understanding whether prospective parents are accepting of
this separation and how it may influence their emotional connection with
the fetus is crucial in the development and implementation of artificial
placental models. Immersion in sterile fluid In summary, the immersion of the fetus in a sterile and warm liquid
environment has numerous advantages in supporting fetal development,
including insulation, temperature regulation, maintenance of lung and
gastrointestinal tract development, and prevention of infection. Balancing
the benefits and potential drawbacks of fetal immersion is essential to
optimize the design and acceptance of artificial placental models (Fig 8). Rauf Melekoğlu / Ayşe Şebnem Erenler Figure 8. A fetal lamb supported by an artificial placenta system, receiving support and
immersed in an amniotic fluid bath (40). Figure 8. A fetal lamb supported by an artificial placenta system, receiving support and
immersed in an amniotic fluid bath (40). Current and Successful Artificial Placenta Models: Design and
Outcomes The quest to replicate fetal and utero-placental physiology has driven
the progress in artificial placenta development, aided by advancements in
technology. Various models have emerged, each employing distinct approaches
to recreate the intricate dynamics of fetal and utero-placental interactions. Over the past decade, the Michigan, Sendai-Perth, and Philadelphia groups
have spearheaded research and analysis of three prominent artificial placenta
models, each with its own level of success. Feeding and medication As the focus shifted towards long-term survival in artificial placental
circuits, the need for improved nutrition became apparent. Dextrose or
glucose infusions alone were insufficient, leading to the addition of amino
acids, lipids, and vitamins to provide a total calorie target of 70-80 kcal/
kg/day. This comprehensive nutritional approach aims to support optimal
growth and organ maturation in the fetus (41). Maintaining ductal patency is crucial for fetal circulation, and the
continuous infusion of prostaglandins (PGE1/PGE2) has become a
standard practice in all artificial placenta models. This helps prevent fatal
ductal narrowing caused by increased oxygen tension (42). To counteract
the thrombogenicity associated with the tubing and oxygenator, heparin
is also continuously infused. However, compared to extracorporeal life
support (ECLS) circuits, the heparinization requirements in artificial
placental models may be reduced due to factors such as decreased surface
area, priming volume, and the systemic inflammatory response (43). In previous studies, intermittent sedation with midazolam and
pentobarbital was utilized to manage periods of fetal agitation and reduce
the risk of traumatic decannulation events. However, recent studies have
questioned the effect of sedatives on fetal neurodevelopment, leading to Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... 134 a cautious approach in their use. Additionally, the use of umbilical cord
cannulation without direct contact to the fetus has decreased the need
for sedation in some cases. It is crucial to avoid prolonged paralysis as it
can negatively impact fetal muscle development and hinder spontaneous
breathing after discontinuation of extracorporeal life support (44). Repetitive phlebotomy for monitoring fetal well-being can lead to progressive
anemia. Daily administration of erythropoietin has been shown to prevent this
anemia, ensuring adequate oxygen-carrying capacity while minimizing the need
for excessive blood sampling. To prevent bacteremia, prophylactic intravenous
broad-spectrum antibiotics and antifungals are commonly administered in
many artificial placenta models, and in some cases, they may be added to
synthetic amniotic fluid. However, in sterile closed circuits, the need for these
interventions is reduced unless contamination occurs (45). Current and Successful Artificial Placenta Models: Design and
Outcomes University of Michigan (USA): Veno-Venous Preterm
Extracorporeal Life Support In the pump-assisted veno-venous (VV) circuit with jugular vein/
umbilical vein (JV/UV) cannulation, the use of a fluid-filled endotracheal
tube replaced immersion in amniotic fluid to address concerns related to
sepsis. This modification extended the mean survival of fetuses from 1
day to nearly 2 weeks, with the maximum reported survival reaching 17
days. Hemodynamic stability was achieved through the administration of
vasopressors, while supraphysiological partial pressures of oxygen were
necessary to ensure adequate oxygenation. However, the maintenance of
ductal patency through prostaglandin E1 (PGE1) infusion proved to be
inconsistent. Although this artificial placenta model successfully rescued late premature
lambs that had previously failed on postpartum mechanical ventilation, it does
not fully align with the primary objective of artificial placental technology, 135 Rauf Melekoğlu / Ayşe Şebnem Erenler which is to delay lung ventilation and thereby preserve lung maturation. The
fetal lambs used in the study were predominantly at the 118- and 130-day
stages of gestation, corresponding to the early and late saccular phases of
lung development, respectively. It is worth noting that borderline human
fetuses at 22-24 weeks of gestation are in the late canalicular phase, which
corresponds to approximately 100 to 110 days of gestation in lambs (46). This discrepancy in lung development stages between the animal model
and human fetuses highlights the need for further research and refinement
in artificial placenta models to better emulate human fetal physiology. Adjustments and adaptations specific to the developmental stage of human
fetuses will be crucial to optimize outcomes and fulfill the goal of preserving
lung maturation in extremely premature infants. Tohoku University, Sendai (Jap) and University of Western
Australia, Perth (Aus): Ex-vivo Uterine Environment (EVE) In 2012, a Japanese team made significant advancements in optimizing the
pumpless arterio-venous (AV) circuit initially developed by the Michigan group. They achieved this by reducing the priming volume and introducing milrinone,
an inotropic vasodilator drug. These modifications led to an increase in survival
time from 4 hours to 30 hours. However, the model still faced limitations due
to progressive circulatory failure caused by high circuit resistance .To address
this issue, the researchers implemented a parallel configuration of two hollow
fiber membrane oxygenators, effectively reducing the circuit resistance by half. This improvement resulted in a further increase in survival time to 1, 2, and
eventually 7 days. External circuit flow regulators were necessary to stabilize
hemodynamics and prevent high cardiac output failure. University of Michigan (USA): Veno-Venous Preterm
Extracorporeal Life Support In order to mitigate
the risks of bacteremia and systemic inflammatory response, the fluid bath was
transformed into a closed, low-volume container, and continuous circulation
of sterilized amniotic fluid was established. Prophylactic administration
of meropenem and fluconazole was incorporated into the amniotic fluid,
both intravenously and locally. Additionally, hydrocortisone was added to
the artificial placenta model to suppress inflammatory responses, promote
lung maturation, and prevent hypocortisolemic refractory hypotension. The
use of corticosteroids successfully alleviated the inflammatory reaction, and
the absence of infection was noted. However, analysis of the brains of the
experimental subjects revealed evidence of brain white matter damage, likely
attributed to systemic hypoperfusion or acute embolic events. These findings
underscore the need for further optimization of the model in preparation
for its potential clinical application. The maximum reported survival time
achieved in this study was 7 days (47). 136 Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... Further research and refinement are necessary to address the remaining
challenges and ensure the safety and efficacy of the artificial placenta model. This includes developing strategies to enhance perfusion to vital organs and
prevent adverse neurological outcomes, among other consideration Philadelphia Children’s Hospital (USA): Extra-Uterine Environment for Neonatal Development (EXTEND) Extra-Uterine Environment for Neonatal Development (EXTEND) In 2017, the Philadelphia team introduced the EXTEND AW model,
which demonstrated promising outcomes in lambs aged 106 to 117 days. The lambs survived for up to 28 days within the artificial placenta model,
followed by successful ventilation. The model utilized a pumpless, low-
resistance, low-surface area heparin-coated arterio-venous (AV) circuit
with umbilical artery/umbilical vein (UA/UV) cannulation. The circuit
maintained stable hemodynamics without the need for external flow
regulators, vasopressors, or corticosteroids. Refractory hypotension was
effectively managed by providing physiological oxygen delivery and circuit
flows. The lambs were immersed in a closed, sterile fluid medium with continuous
exchange of synthetic amniotic fluid, eliminating the need for prophylactic
antimicrobials. Notably, the absence of bacteremia was observed throughout
the study. The Philadelphia team reported long-term stable hemodynamics,
somatic growth, and sustained organ maturation in the lambs. The lungs of
the lambs in the EXTEND model progressed naturally from the canalicular
to the saccular phase of lung development, without the use of corticosteroids
or tracheal occlusion. Assessment of pulmonary function during mechanical
ventilation showed comparable results to age-matched control lambs. Brain analysis revealed normal cerebral maturation, with no evidence of
white matter damage or intracranial hemorrhage. It is worth noting that
fetal lambs are considered to be less prone to intracranial bleeding compared
to human fetuses, as sheep experience earlier germinal matrix maturation. Neurodevelopmental maturation in the lambs within the artificial placenta
model was demonstrated by the progressive consolidation of sleep/wake
cycles, measured through ocular electromyography. Transiently decreased cardiac contractility was observed during a one-
week adaptation phase in the circuit, followed by normal cardiac function
and contractility for the remainder of the study. No myocardial damage or
inflammation was observed, and the heart development and structure in the
circuit lambs were comparable to age-matched controls. 137 Rauf Melekoğlu / Ayşe Şebnem Erenler While specific assessments of liver and kidney function have not been
reported yet, metabolic parameters reflecting kidney function remained
stable. Mild increases in hepatic function tests and bilirubin levels were
observed during the study period, which may be attributed to the absence of
maternal elimination rather than indicating hepatic dysfunction (48) The EXTEND AW model developed by the Philadelphia team
demonstrates promising outcomes, including stable hemodynamics, normal
organ development, and neurological maturation in lambs within the
artificial placenta model. Extra-Uterine Environment for Neonatal Development (EXTEND) Further studies are needed to evaluate liver and
kidney function, as well as to address any potential long-term effects and
optimize the model for future clinical applications (Fig 9). Figure 9.The UA/UV Biobag system design includes a pumpless, low-resistance
oxygenator circuit, a closed fluid environment with continuous fluid exchange, and an
umbilical vascular interface. The figure shows a representative lamb cannulated at 107
days of gestation and on day 4 of support, as well as the same lamb on day 28 of support,
demonstrating somatic growth and maturation(49). Figure 9.The UA/UV Biobag system design includes a pumpless, low-resistance
oxygenator circuit, a closed fluid environment with continuous fluid exchange, and an
umbilical vascular interface. The figure shows a representative lamb cannulated at 107
days of gestation and on day 4 of support, as well as the same lamb on day 28 of support,
demonstrating somatic growth and maturation(49). 138 Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... Challenges in clinical practice Significant progress has been made in artificial placenta technology over
the past decade, bringing it closer to clinical implementation. However,
several challenges still need to be addressed. One challenge is the reduction of oxygenator surface area and improvement
of hemocompatibility through the use of new biomaterial coatings. This
can help minimize the need for systemic anticoagulation, thereby reducing
the risk of bleeding complications. Restoring placental alignment to allow
for pulsatile flow from umbilical arteries to transition into laminar flow
in the umbilical vein has not yet been achieved in recent artificial placenta
models. Incorporating a closed, compliant pressure chamber into the
system can prevent pulsatile flows from reaching the fetal right heart via
the umbilical vein. Optimizing nutrition, growth factors, and amniotic fluid
composition is essential for promoting proper somatic growth within the
artificial placenta system. Exploring enteral nutrition strategies, as opposed
to solely relying on parenteral nutrition (TPN), may be advantageous for the
developing gut and reduce the risks associated with TPN-related cholestasis. Therefore, further investigation in this area is necessary. The widespread
application of artificial placenta technology in emergency scenarios, such
as premature rupture of membranes, requires standardized patient selection
criteria and the development of a simple, fast, and effective cannulation
technique. Advancements in these areas will contribute to the creation of an
ideal artificial placenta model. Conclusion Artificial placenta technology is an evolving field of study that has
captivated the scientific community for over six decades. Progress in circuit
configuration, oxygenator technology, vascular access, fluid immersion,
sterility, nutrition, and medical therapy has significantly advanced this
technology, bringing it closer to mimicking utero-placental physiology. Recent experimental models have demonstrated improved survival rates
and hemodynamic stability, allowing for safety assessments in preparation
for future clinical applications. Despite these promising results, challenges
remain along the path to clinical implementation. Furthermore, artificial
placenta technology not only holds great clinical potential but also provides
exciting opportunities for further research endeavors. 139 Rauf Melekoğlu / Ayşe Şebnem Erenler References Nicolaides KH. First-trimester screening for chromosomal anomalies. Semin
Perinatol. 2005; 29:190–194. Lally M, Valentine-French S. Lifespan Development: A Psychological Perspecti-
ve Second Edition. http://dept.clcillinois.edu/psy/LifespanDevelopment. pdf (2019) Huppertz B. The anatomy of the normal placenta. J Clin Pathol. 2008
Dec;61(12):1296-302. Cleveland clinic web site. Placenta. Figure. https://my.clevelandclinic.org/he-
alth/body/22337-placenta (2023). Beall MH, van den Wijngaard JP, van Gemert MJ, Ross MG. Amniotic fluid
water dynamics. Placenta. 2007;28(8-9):816-23. Sanjay BB, Bimbisar BM. Homicide by smothering masqueradedas Accidental
ElectrocutionInternational Journal of Education and Research in Health
Sciences, July-September 2016;2(3):46-49 Fraser J, Walls M, McGuire W. Respiratory complications of preterm birth. BMJ. 2004; 329(7472): 962–965. Chrıstıan l. Hermansen and Kevın N. Lorah. Respiratory Distress in the New-
born Am Fam Physician. 2007;76(7):987-994. Health Jade Web Site. Infant respiratory distress syndrome. https://healthjade. net/infant-respiratory-distress-syndrome (2023) Brion LP, Primhak RA, Ambrosio-Perez I. Diuretics acting on the distal renal
tubule for preterm infants with (or developing) chronic lung disease. Co-
chrane Database Syst Rev 2003;(4) Davisa R, Brynera B, Mychaliska GB. A paradigm shift in the treatment of extreme
prematurity: the artificial placenta. Curr Opin Pediatr 2014;26(3):370-6. Westin B, Nyberg R, Enhorning G. A technique for perfusion of the previable
human fetus. Acta Paediatr 1958; 47:339–349. Callaghan JC, Maynes EA, Hug HR. Studies on lambs of the development of an
artificial placenta. Review of nine long-term survivors of extracorporeal
circulation maintained in a fluid medium. Can J Surg 1965; 8:208–213. Ballard PL, Granberg P, Ballard RA. Glucocorticoid levels in maternal and cord
serum after prenatal betamethasone therapy to prevent respiratory dist-
ress syndrome. J Clin Investig 1975; 56:1548–1554. 8. Liggins GC, Howie RN. A controlled trial of antepartum glucocorticoid tre-
atment for prevention of the respiratory distress syndrome in premature
infants. Pediatrics 1972; 50:515–525. Awad JA, Cloutier R, Fournier L, et al. Pumpless respiratory assistance using
a membrane oxygenator as an artificial placenta: a preliminary study in
newborn and preterm lambs. J Invest Surg 1995; 8:21–30. 140 Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... Stephen D. Artificial placenta: Analysis of recent progress Bird European Journal
of Obstetrics & Gynecology and Reproductive Biology. 2017;208:61–70. Church J, Perkins E, Coughlin M, Mychaliska GB. Perfluorocarbons Prevent
Lung Injury and Promote Development during Artificial Placenta Support
in Extremely Premature Lambs. Neonatology . 2018; 113(4):313-321. Rochow N, Chan EC, Wen-I , Selvaganapathy PR. Artificial Placenta - Lung
Assist Devices for Term and Preterm Newborns with Respiratory Failure. References Int J Artf Organs. 2013;36:6. Reoma JL, Rojas A, Kim AC, et al. Development of an artificial placenta I:
pumpless arterio-venous extracorporeal life support in a neonatal sheep
model. J Pediatr Surg. 2009;44(1):53-59. Rochow N, Chan EC, Wu WI, et al. Artificial placenta–lung assist devices for
term and preterm newborns with respiratory failure. Int J Artif Organs. 2013;36(6):377-391. Partridge EA, Davey MG, Hornick MA, Flake AW. An Extrauterine environ-
ment for neonatal development: EXTENDING fetal physiology beyond
the womb. Semin Fetal Neonatal Med. 2017;22(6): 404-409. Kuwabara Y, Okai T, Imanishi Y, et al. Development of Extrauterine fetal incu-
bation system using extracorporeal membrane oxygenator. Artif Organs. 1987;11(3):224-227. Kuwabara Y, Okai T, Kozuma S, et al. Artificial placenta: long-term extrauterine
incubation of isolated goat fetuses. Artif Organs. 1989; 13(6):527-531 Miura Y, Matsuda T, Funakubo A, et al. Novel modification of an artificial pla-
centa: pumpless arteriovenous extracorporeal life support in a premature
lamb model. Pediatr Res. 2012;72(5):490-494. Gaylor JDS. Membrane oxygenators: current developments in design and app-
lication. J Biomed Eng. 1988;10(6):541-547. Acharya G, Sonesson SE, Flo K, Rasanen J, Odibo A. Hemodynamic aspects of
normal human feto-placental (umbilical) circulation. Acta Obstet Gyne-
col Scand. 2016;95(6):672-682. Arens J, Schnoering H, Pfennig M, et al. The Aachen MiniHLM–a miniaturized
heart-lung machine for neonates with an integrated rotary blood pump. Artif Organs. 2010;34(9):707-713. Wen-I W, Niels Rochow, Emily C Chan,.Lung assist device: Development of
microfluidic oxygenators for preterm infants with respiratory failure. 2013;13(13) Fujimori K, Murata Y, Quilligan EJ, Nagata N, Hirano T, Sato A. Distributi-
on of oxygenated blood flow at three different routes of extracorporeal
membrane oxygenation in exteriorized fetal lambs. J Obstet Gynaecol
Res. 2001;27(2):103-109. 141 Rauf Melekoğlu / Ayşe Şebnem Erenler | Wallace JM, Bourke DA, Aitken RP, Leitch N, Hay WW. Blood flows and
nutrient uptakes in growth-restricted pregnancies induced by over-
nourishing adolescent sheep. Am J Phys Regul Integr Comp Phys. 2002;282(4):1027-1036. Alexander DP, Britton HG, Nixon DA. Survival of the foetal sheep at term fol-
lowing short periods of perfusion through the umbilical vessels. J Physi-
ol. 1964;175(1):113-124. Partridge EA, Davey MG, Hornick MA, et al. An extra-uterine system to
physiologically support the extreme premature lamb. Nat Commun. 2017;8:15112. Stehbens WE, Wakefield JSJ, Gilbert-Barness E, Zuccollo JM. Histopathology
and ultrastructure of human umbilical blood vessels. Fetal Pediatr Pathol. 2005;24(6):297-315 Teitel DF, Iwamoto HS, Rudolph AM. Changes in the pulmonary circulation
during birth-related events. Pediatr Res. 1
Assistant Professor; Department of Pharmaceutical Toxicology, Erzincan Binali Yıldırım
University Faculty of Pharmacy, Erzincan, Turkey, e-mail address: ecz.busrademir@gmail.
com, ORCID: 0000-0002-9926-107X Abstract Stat proteins, transcription factors that convert extracellular stimuli into
appropriate biological responses, are involved in many normal physiological
cell processes, including proliferation, differentiation, apoptosis, angiogenesis,
and immune system regulation. Irregular Stat activation is often associated
with tumorigenesis. This situation has made the Stat pathway an interesting
target for drug development studies in cancer treatment and has led to
the development of various inhibitors targeting this pathway. Stat signal
inhibitors are divided into two main groups as inhibitors with direct and
indirect effects. Direct inhibitors target the SH domain, DNA binding
domain, or N-terminal domain of the Stat3 protein; indirect inhibitors target
upstream components of the Stat3 pathway, such as JAK2 and EGFR. It
is known that Stat3 has a strong relationship with the formation of breast
cancer and its permanent activation is most pronounced in breast cancer. In
this study, primarily the components of the Stat signaling pathway, activation/
inactivation and the functions of Stat3 were emphasized, the inhibitors that
act by directly inhibiting the SH2 domain of Stat3 proteins in breast cancer
cells were focused, and the results of the research examining the effects of
these inhibitors on breast cancer cells were compiled. Targeting the SH2 Domain of STAT3 Proteins in
Breast Cancer Treatment Busra Demir Cetinkaya1 References 1990;27(4 Pt 1): 372-378. Morton SU, Brodsky D. Fetal physiology and the transition to extrauterine life. Clin Perinatol. 2016;43(3):395-407 Miura Y, Usuda H, Watanabe S, et al. Stable control of physiological parame-
ters, but not infection, in preterm lambs maintained on ex vivo uterine
environment therapy. Artif Organs. 2017;41(10): 959-968 Partridge EA, Davey MG, Hornick MA, et al. An extra-uterine system to
physiologically support the extreme premature lamb. Nat Commun. 2017;8:15112. Felix R. De Bie, Marcus G. Davey, Abby C. Larson, Jan Deprest, Alan W. Flake. Artificial placenta and womb technology: Past, current, and future challen-
ges towards clinical translation. Prenatal Diagnosis. 2021;41:145–158. IEEE Engineering in Medicineand Biology Society. https://bioengineer.org/ar-
tificial-womb-born (2023). Partridge EA, Davey MG, Hornick MA, et al. An extra-uterine system to
physiologically support the extreme premature lamb. Nat Commun. 2017;8:15112. Sakata M, Hisano K, Okada M, Yasufuku M. A new artificial placenta with a
centrifugal pump: Long-term total extrauterine support of goat fetuses. J
Thorac Cardiovasc Surg. 1998;115(5):1023-1031. Miura Y, Matsuda T, Usuda H, et al. A parallelized Pumpless artificial placenta
system significantly prolonged survival time in a preterm lamb model. Artif Organs. 2016;40(5) Unno N, Kuwabara Y, Okai T, et al. Development of an artificial placenta: sur-
vival of isolated goat fetuses for three weeks with DE BIE ET AL. 155
umbilical arteriovenous extracorporeal membrane oxygenation. Artif Or-
gans. 1993;17(12):996-1003. 142 | Advancing Medical Frontiers: Unveiling the Potential of Artificial Placenta in Perinatal... Usuda H, Watanabe S, Saito M, et al. Successful use of an artificial placenta to
support extremely preterm ovine fetuses at the border of viability. Am J
Obstet Gynecol. 2019;221(1) Bryner BS, Mychaliska GB. ECLS for preemies: the artificial placenta. Semin
Perinatol. 2014 Mar;38(2):122-9. Miura Y, Saito M, Usuda H, Woodward E, Rittenschober-Böhm J, Kannan
PS, Musk GC, Matsuda T, Newnham JP, Kemp MW. Ex-Vivo Uterine
Environment (EVE) Therapy Induced Limited Fetal Inflammation in a
Premature Lamb Model. Plos One. 2015 Oct 16;10(10). Emily A Partridge , Marcus G Davey , Matthew A Hornick , Alan W Flake . An EXTrauterine environment for neonatal development: EXTEN-
DING fetal physiology beyond the womb. Semin Fetal Neonatal med. 2017;22(6):404-409. Emily A. Partridge, Marcus G. Davey, Matthew A. Hornick, Patrick E. McGo-
vern, et all. An extra-uterine system to physiologically support the extre-
me premature lamb.Nature Communications. 2017; 8:5112. Chapter 10 Introduction Signal converter and transcription activator (Stat) proteins are transcription
factors that convert extracellular stimuli into appropriate biological responses
(Catlett-Falcone, Dalton, & Jove, 1999). Stat proteins were first identified
in 1994 as key proteins involved in cytokine signaling and interferon-
related antiviral activity (Jr, Kerr, & Stark, 1994; Sadowski, Shuai, Jr, & https://doi.org/10.58830/ozgur.pub128.c630 https://doi.org/10.58830/ozgur.pub128.c630 143 Targeting the SH2 Domain of STAT3 Proteins in Breast Cancer Treatment 144 Gilman, 1993). Over time, they have been found to be involved in many
normal physiological cell processes, including proliferation, differentiation,
apoptosis, angiogenesis, and immune system regulation (Verhoeven et al.,
2020). The Stat protein family consists of seven members, Stat1, Stat2,
Stat3, Stat4, Stat5a, Stat5b, and Stat6 (Logotheti & Pützer, 2019). All
Stat proteins consist of structurally and functionally conserved regions
(Verhoeven et al., 2020). Although each is encoded by a separate gene
(Furqan et al., 2013), they show high homology in their functional domains
(Logotheti & Pützer, 2019). Structurally functional parts of Stat proteins;
The N-terminal domain (ND), DNA binding domain, coiled-coil domain
(CCD), Src-homology 2 (SH2) domain, and C-terminal transcriptional
activation domain (TAD) each have an important function. ND mediates
homo- and heterodimerization of Stat monomers with the highly conserved
SH2 domain, which is the target of many Stat inhibitors. The DNA binding
domain enables the DNA and Stat complex to form. CCD functions as a
nuclear localization signal. The C-terminal transcription domain with highly
conserved phosphorylated tyrosine (Y) and serine (S) residues recruits
additional transcriptional activators and enhances the transcriptional activity
of Stat (Verhoeven et al., 2020; Xin et al., 2020). Stat structural domains
are shown in Figure 1. Figure 1: Schematic representation of STAT structural domains Figure 1: Schematic representation of STAT structural domains 1. ACTIVATION of STAT SIGNALING PATHWAY The activation process of Stats begins following the binding of cytokines,
growth factors, and hormones to their receptors on the cell surface (Turkson
& Jove, 2000). These receptors are receptor-related tyrosine kinases such as
Janus kinase (JAK) or receptors with intrinsic tyrosine kinase activity such as
Platelet-derived growth factor receptor (PDGFR), Epidermal growth factor
recepor (EGFR), Fms-like tyrosine kinase 3 (FLT3). Stats are also known
to be activated by constitutively active non-receptor protein tyrosine kinases
(PTKs) such as c-Src Bcr-Abl and Breast tumor kinase (Brk) (Buettner, Mora,
& Jove, 2002; Furqan et al., 2013; Weaver & Silva, 2007). With specific
phosphorylation of Stat proteins by these tyrosine kinases (Furqan et al.,
2013), the two Stat monomers form dimers via reciprocal phosphotyrosine-
SH2 interactions, translocate to the nucleus, and bind to Stat-specific 145 Busra Demir Çetinkaya DNA response elements of target genes to induce gene transcription
(Turkson & Jove, 2000) and mediate processes related to cellular immunity,
proliferation, apoptosis and differentiation (Logotheti & Pützer, 2019). However, the functionality of Stat proteins is not limited to forming dimers
by phosphorylation. Unphosphorylated Stat dimers and tetramer/oligomer
conformations also play a role in the functionality of some Stats (Moriggl et
al., 2005; Park et al., 2016). Two nonphosphorylated Stat dimers can form
tetramers with N-terminal oligomerization domains, stabilizing its binding
to DNA (Y. Zhao et al., 2013). The regulation of the Stat signaling pathway
is shown in Figure 2. DNA response elements of target genes to induce gene transcription
(Turkson & Jove, 2000) and mediate processes related to cellular immunity,
proliferation, apoptosis and differentiation (Logotheti & Pützer, 2019). However, the functionality of Stat proteins is not limited to forming dimers
by phosphorylation. Unphosphorylated Stat dimers and tetramer/oligomer
conformations also play a role in the functionality of some Stats (Moriggl et
al., 2005; Park et al., 2016). Two nonphosphorylated Stat dimers can form
tetramers with N-terminal oligomerization domains, stabilizing its binding
to DNA (Y. Zhao et al., 2013). The regulation of the Stat signaling pathway
is shown in Figure 2. Figure 2: Regulation of STAT signaling pathway Figure 2: Regulation of STAT signaling pathway 146 | Targeting the SH2 Domain of STAT3 Proteins in Breast Cancer Treatment 2. NEGATIVE REGULATORS of STAT SIGNALING
PATHWAY The state of activation of stat proteins is transient. Activated Stat
proteins are deactivated within hours and returned to the cytoplasm (Calò
et al., 2003). Inactivation of Stat proteins is mediated by suppressor of
cytokine signaling (SOCS), protein inhibitor of activated Stat (PIAS),
and negative regulators including phosphatases (T. K. Kim & Maniatis,
1996). SOC is also known as JAK binding proteins (JABs) or cytokine-
induced SH2 (CIS) proteins or Stat-induced Stat inhibitors (SSI) (Calò
et al., 2003). The SOCS family consists of eight members, namely SOCS-
1/JAB/SSI-1, SOCS-2, SOCS-3, SOCS-4, SOCS-5, SOCS-6, SOCS-
7 and CIS (Lim & Cao, 2006). They inhibit Stat proteins by different
mechanisms based on suppression of JAKs or competition for receptor
binding (Lim & Cao, 2006). Namely; SOCS-1 suppresses JAK activity
through direct interaction, while SOCS-3 inhibits Stat activation by
first interacting with the phosphorylated receptor and then interacting
with JAKs. CIS inhibits activation by competing with Stats for the same
docking site on phosphorylated receptors (Lim & Cao, 2006). Some
SOCS genes are transcriptionally regulated by Stats themselves, forming
part of a classical negative feedback loop for cytokine signaling, indicating
that Stats can negatively regulate their phosphorylation states (Calò et al.,
2003; Desrivières et al., 2006). It is also known that SOCS proteins can
cause receptor protein turnover mediated proteolytic degradation process
via a ubiquitin-proteasome (Krebs & Hilton, 2001). A second class of proteins that cause inactivation of Stat proteins is
the protein inhibitor of activated Stat (PIAS). These proteins interact
directly with Stat dimers in the nucleus to form protein complexes and
block transcription. Namely; The resulting complexes cannot induce gene
transcription because they do not bind to DNA or because nuclear co-
repressor molecules are recruited into transcription complexes (Desrivières
et al., 2006; Hodge, Hurt, & Farrar, 2005). The mammalian PIAS family,
which consists of PIAS1, PIAS3, PIASy, PIASxa/ARIP3, and PIASxb/Miz1
have a certain degree of specificity towards Stat members; PIAS1 and PIASy
are specific to Stat1, PIAS3 to Stat3 and Stat5, and PIASx to Stat4 (Liu &
Shuai, 2003). Another group of negative regulators of stat proteins is phosphatases. TC45, a nuclear tyrosine phosphatase in this group, deactivates phosphorylated
Stats in the nucleus (Desrivières et al., 2006). 3. THE ROLE of STAT3 PROTEINS in the BREAST GLAND Stat3 and Stat5 proteins are involved in fundamental changes in the
mammary gland, including processes such as lactation and involution. Mice
deficient in Stat3 have been found to die during early embryogenesis (Takeda
et al., 1997). Mammary gland involution is a multi-step process in which the
lactating gland morphologically returns to a state close to the pre-pregnancy
state and a high degree of epithelial cell death and stromal rearrangement
occurs (Groner & von Manstein, 2017; Stein, Salomonis, & Gusterson,
2007). Stat3 signaling induces epithelial cell death to clear differentiated
milk-producing cells during involution (Groner & von Manstein, 2017). It
has been shown that the disappearance of the lactation stimulus causes Stat3
phosphorylation to initiate involution, but the upregulation of pStat3 is
not due to the decrease in lactogenic hormones, while Leukemia inhibitory
factor (LIF) is the first activator of Stat3 during involution (Hughes &
Watson, 2018; Kritikou et al., 2003; M. Li et al., 1997). 2. NEGATIVE REGULATORS of STAT SIGNALING
PATHWAY There is evidence that TC45 is
a related Stat phosphatase for Stat1 and Stat3, and has also been reported to 147 Busra Demir Çetinkaya be involved in the regulation of cytoplasmic dephosphorylation of JAK1 and
JAK3 (Ibarra-Sanchez et al., 2000; Simononic, Lee-Loy, Barder, Tremblay,
& McGlade, 2002). In addition to TC45, tyrosine phosphatases such as SHP1 and SHP2
are localized in the cytoplasm and have SH2 domains. These phosphatases
disrupt JAK/Stat signaling by interacting with SH2 domains and
phosphorylated tyrosine residues of JAKs and Stats (Desrivières et al.,
2006). CD45, an active transmembrane molecule in hematopoietic cells,
and PTP1B and TC-PTP phosphatases active in the cytoplasm of these cells
are among the phosphatases responsible for the negative regulation of Stat
proteins (Desrivières et al., 2006). 4. THE ROLE of STAT3 PROTEINS in BREAST CANCER Stat3 is overactive in many types of cancer as a result of autocrine and
paracrine stimulation by cytokines and growth factors such as interleukins
(IL-6, IL-10, IL-12), interferons (IFNs), granulocyte colony stimulating
factor (G-CSF or CSF3), prolactin (PRL), growth hormone (HGH),
epidermal growth factor (EGF) , hepatocyte growth factor (HGF), essential
fibroblast growth factor (FGF2), virus proteins (e.g., v-Src, v-Fps, v-Sis)
or due to persistent activation via Intrinsic tyrosine kinase activities such
as erb-b2 receptor tyrosine kinase 2 (ERBB2), epidermal growth factor
receptor (EGFR), and hepatocyte growth factor receptor HGFR, non-
receptor tyrosine kinases (such as c-Src and c-abl) or G protein-coupled
receptor (Kortylewski, Jove, & Yu, 2005; Lim & Cao, 2006). It is known Targeting the SH2 Domain of STAT3 Proteins in Breast Cancer Treatment 148 that Stat3 is strongly associated with breast cancer formation and its
permanent activation is most prominent in breast cancer (Groner & von
Manstein, 2017). Stat3 has been shown to be constitutively activated in approximately 70%
of breast tumors (Alvarez et al., 2005). Although activated in all types of
breast cancer, it has been most commonly associated with triple-negative
breast cancer that lacks estrogen receptor (ER) or progesterone receptor (PR)
expression and does not show Her2 amplification (L. Marotta et al., 2011;
S.R Walker et al., 2009). It is an interesting paradox that Stat3 protein, which
is involved in every stage of mammary gland development and has important
roles in the basic changes in the mammary gland, has a strong relationship
with mammary tumor formation (Groner & von Manstein, 2017; Sarah R. Walker, Xiang, & Frank, 2014). In normal breast cells, Stat3 is activated by
Leukemia inhibitory factor (LIF) to promote involution with the abolition
of the lactation stimulus (Hughes & Watson, 2018; Sarah R. Walker et al.,
2014), whereas in many breast cancer cell lines, it is activated in an autocrine
fashion by interleukin-6 (IL-6) produced by These cells (Lieblein et al., 2008;
L. Marotta et al., 2011). Stat3, which is constantly in the activated state; can
lead to malignant cell behavior by upregulating genes such as B-cell lymphoma
2 (BCL2), B-cell lymphoma-extra large (BCL-XL), Myeloid Cell Leukemia
Sequence 1 (MCL1) that play a role in apoptosis, gene expression of cyclin D,
the main target of transcriptional control of the cell cycle and other cell cycle
and survival-related genes such as B -cell lymphoma 2 (BCL2), myc proto-
oncogene (c-MYC). 4. THE ROLE of STAT3 PROTEINS in BREAST CANCER (Igelmann, Neubauer, & Ferbeyre, 2019). Recent studies
have shown that Stat3 promotes the process of malignant transformation by
activating genes involved in the Phosphoinositide 3-Kinase (PI3K) /AKT/
Mammalian Target of Rapamycin (mTOR) pathway, the Nuclear Factor
Kappa-Light-Chain Enhancer of Activated B-Cells (NF-κB) pathway, and
the cell cycle regulation pathway (Banerjee & Resat, 2016; Igelmann et al.,
2019). Oncostatin M (OSM), a member of the IL-6 cytokine family, can
promote breast cancer progression by inducing upregulation of IL-6 and
phosphorylation of stat3 (Ma, Qin, & Li, 2020; Tawara, Scott, Emathinger,
Ide, et al., 2019; Tawara, Scott, Emathinger, Wolf, et al., 2019). In addition,
while IL-35 inhibits conventional T (T-conv) cells and promotes breast cancer
progression through Stat3 and Stat1 activation, IL-8 and growth-regulated
oncogene (GRO) chemokines contribute to breast cancer progression by
activating Stat3 (Hao). et al., 2018; Ma et al., 2020; Valeta-Magara et al.,
2019). Stat3 is also known to contribute to breast cancer metastasis. Stat3
along with IL-6 has been shown to contribute to the malignant phenotype 149 Busra Demir Çetinkaya of cancer cell by upregulating the expression of the EMT-inducing Twist,
in part by promoting invasion and epithelial-mesenchymal transition (Lo
et al., 2007; Sullivan et al., 2009; Sarah R. Walker). et al., 2014; Yadav,
Kumar, Datta, Teknos, & Kumar, 2011). Stat3 is known to contribute to
breast cancer metastasis by upregulating Matrix metallopeptidase 2 (MMP2),
Matrix metallopeptidase 9 (MMP9), Snail, Slug, and vimentin (Kamran, Patil,
& Gude, 2013; Z. Li et al., 2019; Ma et al., 2020). Stat3 is a protein that
also affects the angiogenesis process of the tumor cell. It contributes to this
process by up-regulating nodal factors of angiogenesis, particularly vascular
endothelial growth factor (VEGF), hypoxia-inducible factor 1 alpha (HIF-
1α), and Matrix metalloproteinase-2 (MMP-2) (Kortylewski et al., 2005). Stat3 is also known to localize to mitochondria, and mito-Stat3 is known
to regulate mitochondrial metabolism and mitochondrial gene expression
(Chueh, Leong, & Yu, 2010; Igelmann et al., 2019; Macias, Rao, Carbajal,
Kiguchi, & DiGiovanni). , 2014; Sala et al., 2019; Wegrzyn et al., 2009;
Q. Zhang et al., 2013). Recent evidence suggests that Stat3 may promote
survival of breast cancer cells through its effects on mitochondrial function
(Gough et al., 2009). These proteins are known to cause drug resistance
as well as processes such as tumor initiation, cell cycle, survival, metastasis
and angiogenesis. 4. THE ROLE of STAT3 PROTEINS in BREAST CANCER Cancer stem cells (CSCs), also called tumor initiating cells
(TICs), are a group of specialized cancer cells found in tumors that have
the ability to self-renew and specifically produce a variety of tumor cells. These cells are considered to be responsible for recurrence and metastasis and
resistance to treatment (Gibbs et al., 2005). In breast cancer, Stat3 has been
shown to be essential for the viability of cancer stem cells (Hirsch, Iliopoulos,
& Struhl, 2013), it has been reported that a non-CSC population can be
transformed into a CSC-like population through OCT-4 regulation of the
IL-6/JAK1/Stat3 signaling pathway (S. Y. Kim et al., 2013). In addition,
it has been found that the JAK2/Stat3 signaling pathway in breast cancer
increases chemoresistance by increasing carnitine palmitoyltransferase 1B
(CPT1B) and fatty acid beta oxidation (FAO) (Wang et al., 2018). It has been
determined that the Src/Stat3 signaling pathway is involved in multidrug
resistance in triple negative breast cancer cells (Tzeng et al., 2018). 4. THE ROLE of STAT3 PROTEINS in BREAST CANCER Cancer stem cells (CSCs), also called tumor initiating cells
(TICs), are a group of specialized cancer cells found in tumors that have
the ability to self-renew and specifically produce a variety of tumor cells. These cells are considered to be responsible for recurrence and metastasis and
resistance to treatment (Gibbs et al., 2005). In breast cancer, Stat3 has been
shown to be essential for the viability of cancer stem cells (Hirsch, Iliopoulos,
& Struhl, 2013), it has been reported that a non-CSC population can be
transformed into a CSC-like population through OCT-4 regulation of the
IL-6/JAK1/Stat3 signaling pathway (S. Y. Kim et al., 2013). In addition,
it has been found that the JAK2/Stat3 signaling pathway in breast cancer
increases chemoresistance by increasing carnitine palmitoyltransferase 1B
(CPT1B) and fatty acid beta oxidation (FAO) (Wang et al., 2018). It has been
determined that the Src/Stat3 signaling pathway is involved in multidrug
resistance in triple negative breast cancer cells (Tzeng et al., 2018). of cancer cell by upregulating the expression of the EMT-inducing Twist,
in part by promoting invasion and epithelial-mesenchymal transition (Lo
et al., 2007; Sullivan et al., 2009; Sarah R. Walker). et al., 2014; Yadav,
Kumar, Datta, Teknos, & Kumar, 2011). Stat3 is known to contribute to
breast cancer metastasis by upregulating Matrix metallopeptidase 2 (MMP2),
Matrix metallopeptidase 9 (MMP9), Snail, Slug, and vimentin (Kamran, Patil,
& Gude, 2013; Z. Li et al., 2019; Ma et al., 2020). Stat3 is a protein that
also affects the angiogenesis process of the tumor cell. It contributes to this
process by up-regulating nodal factors of angiogenesis, particularly vascular
endothelial growth factor (VEGF), hypoxia-inducible factor 1 alpha (HIF-
1α), and Matrix metalloproteinase-2 (MMP-2) (Kortylewski et al., 2005). Stat3 is also known to localize to mitochondria, and mito-Stat3 is known
to regulate mitochondrial metabolism and mitochondrial gene expression
(Chueh, Leong, & Yu, 2010; Igelmann et al., 2019; Macias, Rao, Carbajal,
Kiguchi, & DiGiovanni). , 2014; Sala et al., 2019; Wegrzyn et al., 2009;
Q. Zhang et al., 2013). Recent evidence suggests that Stat3 may promote
survival of breast cancer cells through its effects on mitochondrial function
(Gough et al., 2009). These proteins are known to cause drug resistance
as well as processes such as tumor initiation, cell cycle, survival, metastasis
and angiogenesis. 5. INHIBITON of STAT3 PROTEINS in BREAST CANCER
TREATMENT Stat signaling inhibitors are divided into two main groups as inhibitors
that act directly and indirectly. Direct inhibitors target the SH domain,
DNA binding domain, or N-terminal domain of Stat3 protein (McMurray,
2006; Xiong, Yang, Shen, Zhou, & Shen, 2014), indirect inhibitors target Targeting the SH2 Domain of STAT3 Proteins in Breast Cancer Treatment 150 upstream components of the Stat3 pathway such as JAK2 and epidermal
growth factor receptor (EGFR) (Thilakasiria et al., 2021). In this review,
we focused on inhibitors that act by directly inhibiting SH2 domain of Stat3
proteins in breast cancer cells. 5.1.1. Peptides and Peptidomimetics Targeting the STAT3 SH2
Domain in Breast Cancer The SH2 domain inhibitor SPI is a 28-mer peptide derived from the
SH2 domain of Stat3. It acts by strongly and selectively inhibiting the Stat3
SH2 domain interaction with the pTyr residue on the cytoplasmic tail of
IL-6R (Xiong et al., 2014) (W. Zhao, Jaganathan, & Turkson, 2010). In
a study by Zhao et al., SPI dose-dependently reduced cell viability and
growth in MDA-MB-231 and MDA-MB-435 breast cancer cell lines with
constitutively activated Stat3, and also induced apoptosis in MDA-MB-231
cells with constitutively activated Stat3 (W. Zhao et al., 2010). Since peptidomimetics have better pharmacokinetic properties than
peptides, peptidomimetic compounds have been developed by using the
peptide XpYL compound as the basic scaffold (Furqan et al., 2013). CJ-
1383 is a cell permeable small molecule peptidomimetic targeting the SH2
domain (Chen et al., 2010; Thilakasiria et al., 2021). In the study of Chen
et al., it was shown that CJ-1383 inhibited cellular Stat3 signaling and
cell growth and induced apoptosis in a dose-dependent manner in MDA-
MB-468 breast cancer cell line with constitutively activated Stat3 (Chen et
al., 2010). S3I-M2001 is an oxazole-based peptidomimetic of the Stat3 SH2
domain-binding phosphotyrosine peptide (K. A. Z. Siddiquee et al., 2007). The compound has been shown to inhibit Stat3-dependent transcription,
transformation, survival and migration in both human and mouse cells by
selectively disrupting Stat3 dimerization (K. A. Z. Siddiquee et al., 2007). In the study of Siddiquee et al., it was determined that S3I-M2001 inhibited
the growth of human breast tumor xenografts (K. A. Z. Siddiquee et al.,
2007). 5.1.2. Nonpeptidic Chemical Inhibitors Targeting the STAT3 SH2
Domain in Breast Cancer 5.1. SH2 Domain Inhibitors or Dimerization Inhibitors The SH2 domain plays a critical role both in mediating the activation of
Stat3 through its interaction with phosphorylated tyrosine residues on the
cytoplasmic portion of the receptors, and in forming dimers of the two Stat3
monomers through reciprocal phosphotyrosine-SH2 interactions (Turkson
& Jove, 2000; Xiong et al., 2014). Stat dimers migrate to the nucleus and
mediate processes related to cellular immunity, proliferation, apoptosis and
differentiation by binding to Stat-specific DNA response elements of target
genes to induce gene transcription (Turkson & Jove, 2000) (Logotheti &
Pützer, 2019). Inhibition of the SH2 domain suppresses the phosphorylation
and activation of the Stat3 protein, resulting in inhibition of the cellular
processes it mediates (Xiong et al., 2014). Considering the mentioned
functions of the SH2 domain, molecules capable of blocking the SH2
domain of Stat3 have been evaluated for the treatment of different tumors
(Tolomeo & Cascio, 2021). It can be said that the SH2 domain inhibits
both the activation and dimerization of Stat3 proteins and is important in
terms of creating an effective treatment approach for cancer treatment by
preventing the dimerization of proteins that escape activation (Berg, 2008). Compounds that inhibit the SH2 domain of Stat3 proteins can be grouped
as peptide and peptidomimetic and non-peptidic chemical inhibitors
(new series of small molecules) considering their chemical structures. The
schematic representation of SH2 domain inhibitors studied in breast cancer
cells is shown in Figure 3. Figure 3: Schematic representation of SH2 domain inhibitors studied in breast cancer
cells Figure 3: Schematic representation of SH2 domain inhibitors studied in breast cancer
cells 151 Busra Demir Çetinkaya | 1 5.1.2. Nonpeptidic Chemical Inhibitors Targeting the STAT3 SH2
Domain in Breast Cancer S3I-201 (also known as NSC 74859) is a low
molecular weight salicylic acid derivative and inhibits Stat3 dimerization by
coupling the salicylic acid moiety with the pTyr binding site of the Stat3-
SH2 domain (K. Siddiquee et al., 2007). S3I-201 significantly inhibited
constitutive Stat3 activation in MDA-MB-231, MDA-MB-435 and MDA-
MB-468 breast cancer cell lines with harbor constitutive Stat3 activation. In
addition, treatment with S3I-201 in all three cell lines caused a decrease in
the number of viable cells, while cell viability was not significantly affected
in the MDA-MB-453 breast cancer cell line which do not harbor aberrant
Stat3 activity. When it was examined whether the loss of cell viability caused
by S3I-201 was mediated by apoptosis, it was determined that S3I-201
significantly induced apoptosis in the MDA-MB-435 breast cancer cell line
with harbor constitutive Stat3 activation. In the same study, it was noted
that S3I-201 caused a significant decrease in the expression of Stat3 target
genes encoding Cyclin D1, Bcl-xL and Survivin in the MDA-MB-231 breast Stattic inhibits the function of the SH2 domain of both unphosphorylated
and phosphorylated Stat3, preventing Stat3 dimerization and binding
to DNA (Berg, 2008) (Xiong et al., 2014). Stattic shows selective Stat3
inhibition; While it does not inhibit Stat1 and Stat5b in vitro, it has been
shown to inhibit Stat3 (Berg, 2008). Stattic has been shown to induce
apoptosis after permanently inhibiting the phosphorylation of Stat3
in breast cancer cell lines MDA-MB-231 and MDA-MB-435, which
constitutively show Stat3 activation (Schust et al., 2006).STA-21 is a
natural deoxytetrangomycin, an angucycline antibiotic (Song, Wang, Wang,
& Lin, 2005). It binds effectively to the SH2 domain of Stat3, effectively
inhibiting Stat3 dimerization and abolishing its nuclear translocation. If we
look at the results of the studies carried out in breast cancer cells in detail;
STA-21 inhibited Stat3-dependent luciferase activity in MDA-MB-435s
breast cancer cell line with constitutively activated Stat3 and showed high
DNA binding activity in these cells. 5.1.2. Nonpeptidic Chemical Inhibitors Targeting the STAT3 SH2
Domain in Breast Cancer The low cell penetration of phosphopeptides led to evaluation of the
efficacy of a “new set of small molecules” for Stat3 SH2 domain inhibition
(Xiong et al., 2014). These non-peptide molecules are cell permeable and
have better physicochemical properties, unlike molecules derived from
peptides or peptidomimetics (Yue & Turkson, 2009). Their mechanism of
action is similar to peptidomimetics: by interacting with the Stat3-SH2
domain, they inhibit Stat3:Stat3 dimerization and thus nuclear translocation
and transcriptional activity (Furqan et al., 2013). Stattic (Stat three-inhibitory compound) was the first non-peptide
inhibitor of Stat3 discovered (Schust, Sperl, Hollis, Mayer, & Berg, 2006). 152 Targeting the SH2 Domain of STAT3 Proteins in Breast Cancer Treatment Stattic inhibits the function of the SH2 domain of both unphosphorylated
and phosphorylated Stat3, preventing Stat3 dimerization and binding
to DNA (Berg, 2008) (Xiong et al., 2014). Stattic shows selective Stat3
inhibition; While it does not inhibit Stat1 and Stat5b in vitro, it has been
shown to inhibit Stat3 (Berg, 2008). Stattic has been shown to induce
apoptosis after permanently inhibiting the phosphorylation of Stat3
in breast cancer cell lines MDA-MB-231 and MDA-MB-435, which
constitutively show Stat3 activation (Schust et al., 2006).STA-21 is a
natural deoxytetrangomycin, an angucycline antibiotic (Song, Wang, Wang,
& Lin, 2005). It binds effectively to the SH2 domain of Stat3, effectively
inhibiting Stat3 dimerization and abolishing its nuclear translocation. If we
look at the results of the studies carried out in breast cancer cells in detail;
STA-21 inhibited Stat3-dependent luciferase activity in MDA-MB-435s
breast cancer cell line with constitutively activated Stat3 and showed high
DNA binding activity in these cells. Another breast cancer cell line with
constitutively active stat3 signaling, MDA-MB-468, also inhibited stat3
DNA binding activity and its donwstream antiapoptotic factors (Bcl-XL and
cyclin D1), but phosphorylation of upstream regulators of Stat3 (P-JAK2,
P-Src, P-EGFR) unaffected by STA-21.In the same study, the effects of STA-
21 on cell growth and survival in breast cancer cell lines with constitutively
active Stat3 activity as well as luciferase activity and DNA binding activity
were investigated: MDA-MB-231, MDA-MB-435s, and MDA-MB-468
(that express persistently activated Stat3) significantly inhibited the survival
of breast cancer cell lines, but showed minimal inhibitory effect on MCF-
7 and MDA-MB-435 breast cancer cells (that have no constitutive Stat3
signaling) (Song et al., 2005). 5.1.2. Nonpeptidic Chemical Inhibitors Targeting the STAT3 SH2
Domain in Breast Cancer Another breast cancer cell line with
constitutively active stat3 signaling, MDA-MB-468, also inhibited stat3
DNA binding activity and its donwstream antiapoptotic factors (Bcl-XL and
cyclin D1), but phosphorylation of upstream regulators of Stat3 (P-JAK2,
P-Src, P-EGFR) unaffected by STA-21.In the same study, the effects of STA-
21 on cell growth and survival in breast cancer cell lines with constitutively
active Stat3 activity as well as luciferase activity and DNA binding activity
were investigated: MDA-MB-231, MDA-MB-435s, and MDA-MB-468
(that express persistently activated Stat3) significantly inhibited the survival
of breast cancer cell lines, but showed minimal inhibitory effect on MCF-
7 and MDA-MB-435 breast cancer cells (that have no constitutive Stat3
signaling) (Song et al., 2005). S3I-201 (also known as NSC 74859) is a low
molecular weight salicylic acid derivative and inhibits Stat3 dimerization by
coupling the salicylic acid moiety with the pTyr binding site of the Stat3-
SH2 domain (K. Siddiquee et al., 2007). S3I-201 significantly inhibited
constitutive Stat3 activation in MDA-MB-231, MDA-MB-435 and MDA-
MB-468 breast cancer cell lines with harbor constitutive Stat3 activation. In
addition, treatment with S3I-201 in all three cell lines caused a decrease in
the number of viable cells, while cell viability was not significantly affected
in the MDA-MB-453 breast cancer cell line which do not harbor aberrant
Stat3 activity. When it was examined whether the loss of cell viability caused
by S3I-201 was mediated by apoptosis, it was determined that S3I-201
significantly induced apoptosis in the MDA-MB-435 breast cancer cell line
with harbor constitutive Stat3 activation. In the same study, it was noted
that S3I-201 caused a significant decrease in the expression of Stat3 target 153 Busra Demir Çetinkaya cancer cell line with constitutive Stat3 activation. In the same study, it was
determined that S3I-201 strongly inhibited tumor growth in human breast
(MDA-MB-231) tumor-bearing mice (K. Siddiquee et al., 2007). BP-102,
an analog of S3I-201, binds to the SH2 domain of Stat3, inhibiting Stat3-
phospho-tyrosine (pTyr) peptide interactions and hence Stat3 activation by
the same mechanism as S3I-201 (X. Zhang et al., 2012). In the study of
Zhang et al., BP-1-102 suppressed cell proliferation, anchorage-dependent
and independent growth, and colony numbers and also induced apoptosis in
MDA-MB-231 breast cancer cells harboring aberrantly active Stat3. Overall,
induction of Focal adhesion kinase (FAK) and paxillin phosphorylation and
downregulation of E-cadherin are thought to contribute to Stat3-mediated
malignant progression. 5.1.2. Nonpeptidic Chemical Inhibitors Targeting the STAT3 SH2
Domain in Breast Cancer Decreased phosphorylation of paxillin and FAK and
increased expression of E-cadherin were seen in MDA-MB-231 cells treated
with BP-1-102. To further investigate the effect of BP-1-102 on Stat3 cross-
talks, the study examined its effect on the production of soluble factors by
tumor cells: In culture medium from MDA-MB-231 cells treated with BP-
1-102, granulocyte colony-stimulating factor (G-CSF), soluble intercellular
adhesion molecule (sICAM) 1 and macrophage migration-inhibitory factor
(MIF)/ glycosylation-inhibiting factor (GIF) levels were found to be lower,
so it was concluded that BP-1-102 inhibited the production of soluble
factors by tumor cells. Again in the same study, it was shown that BP-1-102
inhibited the growth of mouse xenografts of human breast (MDA-MB-231)
tumor that harbor aberrantly active Stat3 as a result of intravenous and oral
gavage administration without any significant changes in body weights or
significant signs of toxicity such as loss of appetite, decreased activity or
lethargy (X. Zhang et al., 2012). 6. CONCLUSION Deregulated activation of the Stat pathway, which is involved in many
normal physiological cell processes, including proliferation, differentiation,
apoptosis, angiogenesis, and immune system regulation (Verhoeven et al.,
2020), is frequently associated with tumorigenesis. It is known that Stat3
is strongly associated with breast cancer formation and its permanent
activation is most prominent in breast cancer (Groner & von Manstein,
2017). Although activated in all types of breast cancer, it has been most
associated with triple-negative breast cancer that lacks estrogen receptor
(ER) or progesterone receptor (PR) expression and does not show Her2
amplification (L. L. C. Marotta et al., 2011; S.R Walker et al., 2009; Sarah
R. Walker et al., 2014). The role of the Stat pathway in cancer development
has made this pathway an interesting target for drug development in cancer Targeting the SH2 Domain of STAT3 Proteins in Breast Cancer Treatment 154 therapy and has led to the development of many inhibitors targeting this
pathway. Stat signaling inhibitors are divided into two main groups as
inhibitors that act directly and indirectly. Direct inhibitors target the SH
domain, DNA binding domain, or N-terminal domain of Stat3 protein
(McMurray, 2006; Xiong et al., 2014), indirect inhibitors target upstream
components of the Stat3 pathway such as JAK2 and epidermal growth factor
receptor (EGFR) (Thilakasiria et al., 2021). In our study, we focused on
inhibitors that act by directly inhibiting the SH2 domain of Stat3 proteins in
breast cancer cells. Considering their chemical structures, these compounds
can be grouped as peptides (SPI), peptidomimetics (CJ-1383, S3I-M2001)
and non-peptidic chemical inhibitors (new series of small molecules)
(Stattic, STA-21, S3I-201, BP-1- 102). When the results of the studies
investigating the effects of these compounds on breast cancer cells with
constitutively active Stat3 signaling were examined, it was observed that
the compounds showed anticarcinogenic effects such as inhibition of cell
viability, migration, induction of apoptosis and inhibition of tumor growth
in breast tumor xenograft models. Based on these results, it can be said that
the SH2 domain of Stat3 is an important target for breast cancer treatment,
worthy of further investigation, and that SH2 domain inhibitors can be
used alone or in combination with existing chemotherapeutics, resulting in
clinically significant results such as higher efficacy and less toxicity. 155 Busra Demir Çetinkaya References References Alvarez, J. ., Febbo, P. ., Ramaswamy, S., Loda, M., Richardson, A., & Frank,
D. . (2005). Identification of a genetic signature of activated signal trans-
ducer and activator of transcription 3 in human tumors. Cancer Research,
65(12), 5054–5062. Banerjee, K., & Resat, H. (2016). Constitutive activation of STAT3 in bre-
ast cancer cells: A review. International Journal of Cancer, 138(11),
2570–2578. Berg, T. (2008). Signal Transducers and Activators of Transcription as Targets
for Small Organic Molecules. ChemBioChem, 9, 2039–2044. Buettner, R., Mora, L., & Jove, R. (2002). Activated STAT signaling in human
tumors provides novel molecular targets for therapeutic intervention. Clinical Cancer Research, 8(4), 945–954. Calò, V., Migliavacca, M., Bazan, V., Macaluso, M., Buscemi, M., Gebbia, N., &
Russo, A. (2003). STAT proteins: from normal control of cellular events
to tumorigenesis. Journal of Cellular Physiology, 197(2), 157–168. Catlett-Falcone, R., Dalton, W. S., & Jove, R. (1999). STAT proteins as novel
targets for cancer therapy. Current Opinion in Oncology, 11(6), 490. Chen, J., Bai, L., Bernard, D., Nikolovska-Coleska, Z., Gomez, C., Zhang, J.,
… Wang, H. (2010). Structure-based design of conformationally cons-
trained, cell-permeable STAT3 inhibitors. ACS Medicinal Chemistry Let-
ters, 1(2), 85–89. Chueh, F. Y., Leong, K. F., & Yu, C. L. (2010). Mitochondrial translocation of
signal transducer and activator of transcription 5 (STAT5) in leukemic
T cells and cytokine-stimulated cells. Biochemical and Biophysical Research
Communications, 402(4), 778–783. Desrivières, S., Kunz, C., Barash, I., Vafaizadeh, V., Borghouts, C., & Groner,
B. (2006). The biological functions of the versatile transcription factors
STAT3 and STAT5 and new strategies for their targeted inhibition. Jour-
nal of Mammary Gland Biology and Neoplasia, 11, 75–87. Furqan, M., Akinleye, A., Mukhi, N., Mittal, V., Chen, Y., & Liu, D. (2013). STAT inhibitors for cancer therapy. Journal of Hematology & Oncology,
6(90). Gibbs, C. ., Kukekov, V. ., Reith, J. ., Tchigrinova, O., Suslov, O. ., Scott, E. .,
… Steindler, D. . (2005). Stem-like cells in bone sarcomas: Implications
for tumorigenesis. Neoplasia, 7, 967–976. Gough, D. ., Corlett, A., Schlessinger, K., Wegrzyn, J., Larner, A. ., & Levy,
D. . (2009). Mitochondrial STAT3 supports Ras-dependent oncogenic
transformation. Science, 324, 1713–1716. 156 | Targeting the SH2 Domain of STAT3 Proteins in Breast Cancer Treatment Groner, B., & von Manstein, V. (2017). Jak Stat signaling and cancer: Oppor-
tunities, benefits and side effects of targeted inhibition. Molecular and
Cellular Endocrinology, 451, 1–14. References Hao, S., Chen, X., Wang, F., Shao, Q., Liu, J., Zhao, H., … Mao, H. (2018). Breast cancer cell–derived IL-35 promotes tumor progression via inducti-
on of IL-35-producing induced regulatory T cells. Carcinogenesis, 39(12),
1488–1496. Hirsch, H. A., Iliopoulos, D., & Struhl, K. (2013). Metformin inhibits the inf-
lammatory response associated with cellular transformation and cancer
stem cell growth. Proceedings of the National Academy of Sciences, 110(3),
972–977. Hodge, D. R., Hurt, E. M., & Farrar, W. L. (2005). The role of IL-6 and STAT3
in inflammation and cancer. European Journal of Cancer, 41, 2502–2512. Hughes, K., & Watson, C. J. (2018). The multifaceted role of STAT3 in mam-
mary gland involution and breast cancer. International Journal of Molecu-
lar Sciences, 19(6), 1695. Ibarra-Sanchez, M., Simoncic, P., Nestel, F., Duplay, P., Lapp, W., & Tremblay,
M. (2000). The T-cell protein tyrosine phosphatase. Seminars in Immuno-
logy, 12(4), 379–386. Igelmann, S., Neubauer, H. A., & Ferbeyre, G. (2019). STAT3 and STAT5 Ac-
tivation in Solid Cancers. Cancers, 11(1428). Jr, J. E. D., Kerr, I. M., & Stark, G. R. (1994). Jak-STAT pathways and transc-
riptional ac- tivation in response to IFNs and other extracellular signaling
proteins. Science, 264(5164), 1415–1421. Kamran, M. Z., Patil, P., & Gude, R. P. (2013). Role of STAT3 in cancer metas-
tasis and translational advances. BioMed Research International. Kim, S. Y., Kang, J. W., Song, X., Kim, B. K., Yoo, Y. D., Kwon, Y. T., & Lee, Y. J. (2013). Role of the IL-6-JAK1-STAT3-Oct-4 pathway in the conversi-
on of non-stem cancer cells into cancer stem-like cells. Cellular Signalling,
25(4), 961–969. Kim, T. K., & Maniatis, T. (1996). Regulation of interferon-γ-activated STAT1
by the ubiquitin-proteasome pathway. Science, 273(5282), 1717–1719. Kortylewski, M., Jove, R., & Yu, H. (2005). Targeting STAT3 affects melanoma
on multiple fronts. Cancer and Metastasis Reviews, 24, 315–327. Krebs, D., & Hilton, D. (2001). SOCS proteins: Negative regulators of cytoki-
ne signaling. Stem Cells, 19, 378–387. Kritikou, E. ., Sharkey, A., Abell, K., Came, P. ., Anderson, E., Clarkson, R. .,
& Watson, C. . (2003). A dual, non-redundant, role for LIF as a regula-
tor of development and STAT3-mediated cell death in mammary gland. Development, 130, 3459–3468. 157 Busra Demir Çetinkaya Li, M., Liu, X., Robinson, G., Bar-Peled, U., Wagner, K. ., Young, W. ., …
Furth, P. A. (1997). Mammary-derived signals activate programmed cell
death during the first stage of mammary gland involution. References 158 | Targeting the SH2 Domain of STAT3 Proteins in Breast Cancer Treatment Moriggl, R., Sexl, V., Kenner, L., Duntsch, C., Stangl, K., Gingras, S., … Beug,
H. (2005). Stat5 tetramer formation is associated with leukemogenesis. Cancer Cell, 7(1), 87–99. Park, H. ., Li, J., Hannah, R., Biddie, S., Leal-Cervantes, A. ., Kirschner, K., …
Green, A. . (2016). Cytokine-induced megakaryocytic differentiation is
regulated by genome-wide loss of a uSTAT transcriptional program. The
EMBO Journal, 35(6), 580–594. Sadowski, H. B., Shuai, K., Jr, J. E. D., & Gilman, M. Z. (1993). A common
nuclear signal transduction pathway activated by growth factor and cyto-
kine receptors. Science, 261(5129), 1739–1744. Sala, D., Cunningham, T. J., Stec, M. J., Etxaniz, U., Nicoletti, C., Dall’Agnese,
A., … Sacco, A. (2019). The Stat3-Fam3a axis promotes muscle stem
cell myogenic lineage progression by inducing mitochondrial respiration. Nature Communications, 10(1), 1796. Schust, J., Sperl, B., Hollis, A., Mayer, T. U., & Berg, T. (2006). Stattic: a
small-molecule inhibitor of STAT3 activation and dimerization. Che-
mistry & Biology, 13(11), 1235–1242. Siddiquee, K. A. Z., Gunning, P. T., Glenn, M., Katt, W. P., Zhang, S., Schroeck,
C., … Turkson, J. (2007). An oxazole-based small-molecule Stat3 inhi-
bitor modulates Stat3 stability and processing and induces antitumor cell
effects. ACS Chemical Biology, 2(12), 787–798. Siddiquee, K., Zhang, S., Guida, W. C., Blaskovich, M. A., Greedy, B., Lawren-
ce, H. R., … Turkson, J. (2007). Selective chemical probe inhibitor of
Stat3, identified through structure-based virtual screening, induces anti-
tumor activity. Proceedings of the National Academy of Sciences, 104(18),
7391–7396. Simononic, P., Lee-Loy, A., Barder, D., Tremblay, M., & McGlade, C. (2002). The T cell protein tyrosine phosphatase is a negative regulator of Janus
family kinases 1 and 3. Current Biology, 12, 446–453. Song, H., Wang, R., Wang, S., & Lin, J. (2005). A low-molecular-weight com-
pound discovered through virtual database screening inhibits Stat3 func-
tion in breast cancer cells. Proceedings of the National Academy of Sciences,
102(13), 4700–4705. Stein, T., Salomonis, N., & Gusterson, B. A. (2007). Mammary Gland Invo-
lution as a Multi-step Process. Journal of Mammary Gland Biology and
Neoplasia, 12, 25–35. Sullivan, N. ., Sasser, A. ., Axel, A. ., Vesuna, F., Raman, V., Ramirez, N., …
Hall, B. . (2009). Interleukin-6 induces an epithelial–mesenchymal tran-
sition phenotype in human breast cancer cells. Oncogene, 28, 2940–2947. References Proceedings of
the National Academy of Sciences, 94(7), 3425–3430. Li, Z., Chen, Y., An, T., Liu, P., Zhu, J., Yang, H., … Yang, X. (2019). Nucife-
rine inhibits the progression of glioblastoma by suppressing the SOX2-
AKT/STAT3-Slug signaling pathway. Journal of Experimental & Clinical
Cancer Research, 38(1), 1–15. Lieblein, J. ., Ball, S., Hutzen, B., Sasser, A. ., Lin, H. ., Huang, T. ., … Lin,
J. (2008). STAT3 can be activated through paracrine signaling in breast
epithelial cells. BMC Cancer, 8, 1–14. Lim, C. P., & Cao, X. (2006). Structure, function, and regulation of STAT pro-
teins. Molecular BioSystems, 2, 536–550. Liu, B., & Shuai, K. (2003). The PIAS protein family and Tc-PTP. In P. B. Seh-
gal, D. E. Levy, & T. Hirano (Eds.), Signal Transducers and Activators of
Transcription (STATs): Activation and Biology (pp. 75–85). Kluwer Acade-
mic Publishers. Lo, H. ., Hsu, S. ., Xia, W., Cao, X., Shih, J. ., Wei, Y., … Hung, M. . (2007). Epidermal growth factor receptor cooperates with signal transducer and
activator of transcription 3 to induce epithelial-mesenchymal transition
in cancer cells via up-regulation of TWIST gene expression. Cancer Rese-
arch, 67, 9066–9076. Logotheti, S., & Pützer, B. M. (2019). STAT3 and STAT5 Targeting for Simul-
taneous Management of Melanoma and Autoimmune Diseases. Cancers,
11(1448). Ma, J., Qin, L., & Li, X. (2020). Role of STAT3 signaling pathway in breast
cancer. Cell Communication and Signaling, 18(33), 1–13. Macias, E., Rao, D., Carbajal, S., Kiguchi, K., & DiGiovanni, J. (2014). Stat3
binds to mtDNA and regulates mitochondrial gene expression in kerati-
nocytes. Journal of Investigative Dermatology, 134(7), 1971–1980. Marotta, L. ., Almendro, V., Marusyk, A., Shipitsin, M., Schemme, J., Walker, S. ., … Lee, H, K. (2011). The JAK2/STAT3 signaling pathway is required
for growth of CD44 + CD24- stem cell-like breast cancer cells in human
tumors. The Journal of Clinical Investigation, 121(7), 2723–2735. Marotta, L. L. C., Almendro, V., Marusyk, A., Shipitsin, M., Schemme, J., Wal-
ker, S. R., … Kornelia Polyak. (2011). The JAK2/STAT3 signaling pat-
hway is required for growth of CD44 + CD24- stem cell-like breast can-
cer cells in human tumors. The Journal of Clinical Investigation, 121(7),
2723–2735. McMurray, J. S. (2006). A New Small-Molecule Stat3 Inhibitor. Chemistry &
Biology, 13(11), 1123–1124. References Takeda, K., Noguchi, K., Shi, W., Tanaka, T., Matsumoto, M., Yoshida, N., …
Akira, S. (1997). Targeted disruption of the mouse Stat3 gene leads to 159 Busra Demir Çetinkaya early embryonic lethality. Proceedings of the National Academy of Sciences,
94(8), 3801–3804. Tawara, K., Scott, H., Emathinger, J., Ide, A., Fox, R., Greiner, D., … Jorcyk,
C. (2019). Co-expression of VEGF and IL-6 family cytokines is associ-
ated with decreased survival in HER2 negative breast cancer patients:
subtype-specific IL-6 family cytokine-mediated VEGF secretion. Transla-
tional Oncology, 12(2), 245–255. Tawara, K., Scott, H., Emathinger, J., Wolf, C., LaJoie, D., Hedeen, D., … Jor-
cyk, C. (2019). HIGH expression of OSM and IL-6 are associated with
decreased breast cancer survival: synergistic induction of IL-6 secretion
by OSM and IL-1beta. Oncotarget, 10, 2068–2085. Thilakasiria, P. S., Dmelloa, R. S., Nerob, T. L., Parkerb, M. W., Ernsta, M., &
Chand, A. L. (2021). Repurposing of drugs as STAT3 inhibitors for can-
cer therapy. Seminars in Cancer Biology, 68, 31–46. Tolomeo, M., & Cascio, A. (2021). The Multifaced Role of STAT3 in Cancer
and Its Implication for Anticancer Therapy. International Journal of Mole-
cular Sciences, 22(2), 603. Turkson, J., & Jove, R. (2000). STAT proteins: novel molecular targets for can-
cer drug discovery. Oncogene, 19(2000), 6613–6626. Tzeng, Y.-D. T., Liu, P.-F., Li, J.-Y., Liu, L.-F., Kuo, S.-Y., Hsieh, C.-W., … Shu,
C.-W. (2018). Kinome-wide siRNA screening identifies Src-enhanced re-
sistance of chemotherapeutic drugs in triple-negative breast cancer cells. Frontiers in Pharmacology, 9, 1285. Valeta-Magara, A., Gadi, A., Volta, V., Walters, B., Arju, R., Giashuddin, S.,
… J, R. S. (2019). No Inflammatory Breast Cancer Promotes Develop-
ment of M2 Tumor-Associated Macrophages and Cancer Mesenchymal
Cells through a Complex Chemokine Network. Cancer Research, 79(13),
3360–3371. Verhoeven, Y., Tilborghs, S., Jacobs, J., Waele, J. De, Quatannens, D., Deben,
C., … Dam, P. A. van. (2020). The potential and controversy of targeting
STAT family members in cancer. Seminars in Cancer Biology, 60(2020),
41–56. Walker, S.R, Nelson, E. ., Zou, L., Chaudhury, M., Signoretti, S., Richardson,
A., & Frank, D. . (2009). Reciprocal effects of STAT5 and STAT3 in bre-
ast cancer. Molecular Cancer Research, 7(6), 966–976. Walker, Sarah R., Xiang, M., & Frank, D. A. (2014). Distinct roles of STAT3
and STAT5 in the pathogenesis and targeted therapy of breast cancer. Molecular and Cellular Endocrinology, 382(1), 616–621. Wang, T., Fahrmann, J. F. H. L., Li, Y.-J., Tripathi, S. 1
Asst.Prof.Dr., Department of Neurology, Dicle University Faculty of Medicine, Diyarbakir,
Türkiye, yyucel@dicle.edu.tr, ORCID ID: 0000-0003-4205-3138
2
Dr., Department of Neurology, Mogadishu Somalia Türkiye Training and Research Hospital,
ziidoow113@gmail.com, ORCID ID:0000-0002-6039-5054 Chapter 11
A General Overview of Epilepsy: its
Classification, and Management Chapter 11 A General Overview of Epilepsy: its
Classification, and Management Yavuz Yücel1
Nor Osman Sidow2 References C., Yue, C., Zhang, C., …
Yu, H. (2018). JAK/STAT3-regulated fatty acid β-oxidation is critical for | Targeting the SH2 Domain of STAT3 Proteins in Breast Cancer Treatment 160 breast cancer stem cell self-renewal and chemoresistance. Cell Metabolism,
27(1), 136–150. Weaver, A., & Silva, C. (2007). Signal transducer and activator of transcription
5b: a new target of breast tumor kinase/protein tyrosine kinase 6. Breast
Cancer Research, 9(6), R79. Wegrzyn, J., Potla, R., Chwae, Y.-J., Sepurı, N. B. V., Zhang, Q., Koeck, T., …
Larner, A. C. (2009). Function of mitochondrial Stat3 in cellular respira-
tion. Science, 323, 793–797. Xin, P., Xua, X., Denga, C., Liua, S., Wang, Y., Zhou, X., … Sun, S. (2020). The role of JAK/STAT signaling pathway and its inhibitors in diseases. International Immunopharmacology, 80(2020), 106210. Xiong, A., Yang, Z., Shen, Y., Zhou, J., & Shen, Q. (2014). Transcription Fac-
tor STAT3 as a Novel Molecular Target for Cancer Prevention. Cancers,
6, 926–957. Yadav, A., Kumar, B., Datta, J., Teknos, T. ., & Kumar, P. (2011). IL-6 pro-
motes head and neck tumor metastasis by inducing epithelial-mesenchy-
mal transition via the JAK-STAT3-SNAIL signaling pathway. Molecular
Cancer Research, 9, 1658–1667. Yue, P., & Turkson, J. (2009). Targeting STAT3 in cancer: how successful are
we? Expert Opinion on Investigational Drugs, 18(1), 45–56. Zhang, Q., Raje, V., Yakovlev, V. A., Yacoub, A., Szczepanek, K., Meier, J., …
Larner, A. C. (2013). Mitochondrial localized Stat3 promotes breast can-
cer growth via phosphorylation of serine 727. Journal of Biological Chem-
istry, 288(43), 31280–31288. Zhang, X., Yue, P., Page, B. D. G., Li, T., Zhao, W., Namanja, A. T., … Turkson,
J. (2012). Orally bioavailable small-molecule inhibitor of transcription
factor Stat3 regresses human breast and lung cancer xenografts. Proceed-
ings of the National Academy of Sciences, 109(24), 9623–9628. Zhao, W., Jaganathan, S., & Turkson, J. (2010). A cell-permeable Stat3 SH2
domain mimetic inhibits Stat3 activation and induces antitumor cell ef-
fects in vitro. Journal of Biological Chemistry, 285(46), 35855–35865. Zhao, Y., Zeng, C., Tarasova, N. ., Chasovskikh, S., Dritschilo, A., & Timofee-
va, O. . (2013). A new role for STAT3 as a regulator of chromatin topol-
ogy. Transcription, 4, 227–231. Abstract Abstract Epilepsy is one of the most common neurological disorders, with about 50 new
cases per 100,000 people each year. It affects roughly 1% of the population
and one-third of patients have refractory seizures. About 75% of patients
present in childhood, reflecting the growing susceptibility of the developing
brain to seizures. The classification of seizures is determined by their onset and
can be divided into four types: focal, generalized, unknown or unclassifiable. The latest classification elaborates the basic categorization system previously
described, extending the “motor” and “non-motor” groupings to include all
three types of seizures (focal, generalized, and unknown). Epilepsy is a difficult diagnosis with no simple, attainable gold standard. The
key to diagnosis is a comprehensive history and reliable eyewitness account. Because no single symptom or sign is specific to epilepsy, determining
whether a seizure has occurred is based on a combination of signs and
symptoms. The primary treatment for diagnosed patients is administration
of anti-seizure medications. The aim is to protect the individual from adverse
effects that could potentially endanger the individual’s standard of living and
to terminate seizures immediately. Epilepsy is a treatable condition; 80% of patients remain seizure-free and
almost 50% remain seizure-free even after treatment is stopped. With more
than 20 drugs used in treatment, it is possible to obtain effective treatment at
rates close to 70% of diagnosed individuals. With this review we wrote, we
aimed to summarize this very broad subject with recent articles. https://doi.org/10.58830/ozgur.pub128.c584 161 162 A General Overview of Epilepsy: its Classification, and Management Background and definitions A “seizure” is a paroxysmal change in neurologic function induced by
the brain’s excessive, hypersynchronous discharge of neurons1. The term
“epileptic seizure” refers to a seizure induced by aberrant neuronal firing as
opposed to a non-epileptic event, such as a photogenic seizure2. The disorder
known as “epilepsy” is characterized by recurring, unprovoked seizures3. A
seizure caused by reversibl insult (eg. Fever, hypoglycemia) does not qualify
as epilepsy because it is a temporary secondary diseases rather than a chronic
condition4. Epilepsy is one of the most prevalent neurologic disorders, with roughly
50 new cases per 100.000 people each year. Epilepsy affects roughly 1% of the
population, and one-third of the patients have refractory epilepsy (seizures
that are not controlled by two or more appropriately chose antiepileptic
medications or other therapy).5 Approximately 75% of epilepsy originated in childhood, reflecting the
developing brain’s increased susceptibility to seiiuzres6. The term “epilepsy
syndrome” refers to a combination of clinical characteristics that occur
together on a continuous basis, such as comparable seizure types(s), age of
onset, and response to antiepileptic drug (AEDs). The broad phase “seizure
disorder” should be avoided7. Wirrell et al. outline in detail the methods used by the International
League Against Epileptic (ILAE) Nosology and Definitions Taskforce
(2017-2021) in defining epileptic syndromes and classifying them by age
of onset8. An epilepsy syndrome is characterized by a distinct set of clinical
and electroencephalographic (EEG) symptoms, which are frequently
accompanied by particular etiological findings (structural, genetic,
metabolic, immunological, and infections). A syndrome diagnosis in a
person with epilepsy typically has prognostic and treatment consequences,
syndromes frequently have age-dependent manifestations and a variety of
unique comorbidities, a conditions has a “variable age” of onset if it can
begin in both 18-year-old and 19-year-old (i.e., in both juvenile and adult
patients)9. The ILAE defines epilepsy as any of the following conditions: (1) the
occurrence of at least two unprovoked (or reflex) seizures that are more than
24 hours apart; (2) the occurrence of one unprovoked (or reflex) seizure with
a possibility of subsequent seizures comparable to the general recurrence risk
(at least 60%) after two unprovoked seizures that occur within the next ten
yea4rs; and (3) the diagn0osi of an epilepsy syndorm10. 163 Yavuz Yücel / Nor Osman Sidow Yavuz Yücel / Nor Osman Sidow The beginning of seizures might be focal (in one hemisphere of the
brain). Background and definitions Generalized (in both hemisphere at the same time), or unknown. Active epilepsy is defined as the use of antiepileptic drugs on a regular basis
or when the most recent seizure happened during the last 5 years. Status
epilepticus (SE) is an epileptic episode that lasts long enough or is repeated
at shout enough intervals to cause an epileptic condition. Depending on the
kind and duration of the seizures, SE might have long-term repercussions
such as neuronal injury or death, as well as changes in the neuronal networks. A new SE diagnostic categorization was recently developed and it will be
seen in the last parts of this chapter11. The beginning of seizures might be focal (in one hemisphere of the
brain). Generalized (in both hemisphere at the same time), or unknown. Sudden Unexpected Death in Epilepsy (SUDEP) is a phenomenon
characterized by sudden, unforeseen, and non-traumatic death in individuals
with epilepsy, whether observed or not, and with or without evidence of a
seizure. This definition excludes documented status epilepticus and requires
that postmortem examination reveals no toxicological or anatomical cause
of death12. Epidemiology and pathophysiology The prevalence of epilepsy varies greatly across nations, based on the
geographical distribution of risk and etiologic variables, the number of
seizures upon diagnosis, and whether active epilepsy (active prevalence) or
cases in remission (lifetime prevalence) is include. According to the Fiest et
al. the total lifetime prevalence of epilepsy was 7.60 per 1,000 population
(95%) confidence interval [CI] 6.17-9.38) and was greater in LMIC 98.75
per 1,000; the median point prevalence of active epilepsy was 6.68 (95% CI
5.45-8.10), while in HIC, it was 5.49 (4.16-7.26)1314. According to the sex, men have somewhat higher incidence and prevalence
of epilepsy than women. The difference might be because the most common
risk factors are more or less common in different places, or because women
in some place hide the disease for social and cultural reasons15. Epilepsy is more common in the youngest and oldest age groups, with
estimates of 86 per 100,000 per year in a well-defined population in the
first year of life (figure 1), dropping to about 23-31 per 100,000 in people
aged 30-59 years, and then going up to 180 per 100,000 in the over 85 age
group. Epilepsy is most common in children in their first of life. By the end
of age 10, the number of children with epilepsy drops to the same level as
adults16. The most common type of seizure in both children and adults is a focal
seizure. About 36% of all people who have seizures have a focal decreased A General Overview of Epilepsy: its Classification, and Management 164 awareness seizure this is the most common type of focal seizure. In most
LMIC, however, generalized tonic-colonic seizures are by far the most
common type. The rate of SE has been found to range from 6.8 to 41 per
100,000 people per year, with peaks in children younger than 1 year and
older people17. Figure 1: Age related prevalence per 100,000 of idiopathic epilepsy by country, 2016 form
global burden of diseases 2016 Figure 1: Age related prevalence per 100,000 of idiopathic epilepsy by country, 2016 form
global burden of diseases 2016 Seizures happen when neurons in a part of the brain or the whole brain
fire at the same time n a way that is not normal. This can happen when
networks are not put together right or when there is a structural, infections,
or metabolic problem. Etiologies of Epilepsy by Age Figure 2: Etiologies of epilepsy according to the age by ILAE Figure 2: Etiologies of epilepsy according to the age by ILAE The condition known as epilepsy is distinguished by an atypical
synchronization of firing among clusters of neurons, which arises form an
in-equilibrium in the neurotransmission on excitatory and inhibitory signals,
historically, epilepsy research has been primarily focused on the neurological
aspects of the conditon. In the past twenty years, there has been a significant
increase in research regarding the function of glial cells in regulating and
altering neuronal activity. This has resulted in compelling evidence supporting
the involvement of glial cells in the development of epilepsy19. Epidemiology and pathophysiology Most seizures in children are caused by genetics,
injuries that happen before or during birth, or problems with how the brain
develops. Common causes of seizures in people who do not have genetic
predisposition of epilepsy include encephalitis/meningitis, traumatic brain
injury, and brain tumors (figure 2). Epilepsy in older people is generally
caused by neurodegenerative disorders, head injuries, or brain tumors. Because the causes of epilepsy are different for different age groups, the
frequency of epilepsy is bimodal, with generic and developmental causes
peaking in childhood and accumulated brain damage (such as from trauma
or tumors) peaking in the elderly. It is important to know that the cause of
about half of all seizures is unknown18. Yavuz Yücel / Nor Osman Sidow | 165 165 Yavuz Yücel / Nor Osman Sidow | Etiologies of Epilepsy by Age Basic classification The categorization of seizures is determined by their initiation and can
be classified into four types: focal, generalized, unknown, or unclassifiable,
as presented in Table 1. The term “focal” can be considered as a synonym
for the previously used term “partial.” The term “generalized” has remained
unaltered. A seizure of generalized onset is characterized by the simultaneous
activation of both hemispheres, which may exhibit asymmetry, at the onset
of the seizure, as determined by behavioral and electroencephalographic
observations. The term “unknown onset” pertains to a scenario wherein
the onset remains unidentified, while other indications are recognized. Further elaboration is provided below. The category of “Unclassified”
persists, although its usage may diminish with the inclusion of novel
seizure types and the “unknown onset” classification. There exist a limited
number of occurrences that are unequivocally seizures, yet they cannot be
categorized20. | A General Overview of Epilepsy: its Classification, and Management 166 Table 1: International League Against Epilepsy 2017 basic classification of seizures. able 1: International League Against Epilepsy 2017 basic classification of seizures. Etiology The revised categorization of epilepsy offers a tripartite diagnostic
structure that underscores the significance of etiological factors throughout
all phases. The initial step involves the delineation of the seizure classification. The second category pertains to epilepsy classification, encompassing focal,
generalized, combined focal and generalized, and epilepsy of unknown
etiology. The third aspect pertains to the diagnosis of the epilepsy syndrome. The classification of etiological categories, which holds significant
implications for management, encompasses structural, genetic, infectious,
metabolic, immune, and unknown factors21. Expanded classification Expanded classification The extended categorization system elaborates on the fundamental
categorization system delineated earlier, by extending the “motor” and
“non-motor” groupings to encompass all three types of seizures (focal,
generalized, and unknown), as presented in tables 2 and 3. Table 2: ILAE 2017 expanded classification of seizures Table 2: ILAE 2017 expanded classification of seizures Yavuz Yücel / Nor Osman Sidow | 167 Table 3: The 2017 ILAE classifications of the Epilepsies Table 3: The 2017 ILAE classifications of the Epilepsies Table 3: The 2017 ILAE classifications of the Epilepsies Table 3: The 2017 ILAE classifications of the Epilepsies Epilepsy syndrome Etiology Diagnostic evaluation Epilepsy is a difficult diagnosis that lacks a simple, obtainable gold
standard. The key to diagnosis is a thorough history and a credible
eyewitness narrative, because no single symptom or sign is distinctive to
epilepsy, the determination of whether a seizure has occurred or not is
based on a combination of symptoms and signs. Epilepsy is polymorphic
with numerous presentations and a wide range of mimics, which adds
to its complexity. Always rule out non-epileptic paroxysmal occurrences
because epilepsy misdiagnoses are frequent and can have negative effects. The most frequent syncope presentation is a brief loss of consciousness, and
the most significant epileptic mimics are those caused by psychogenic or
functions factors. All people who may be having seizure should be given
electrocardiogram, especially if they also have a brief loss of consciousness. Epilepsy is not defined by an abnormal electroencephalogram (EEG), but A General Overview of Epilepsy: its Classification, and Management 168 inter-ictal epileptiform discharges may support a clinical diagnosis. Finding
the likely type of epilepsy (focal or generalized), diagnosing and epileptic
syndrome, and determining the likelihood of recurrence are all made easier
by an abnormal EEG. Long-term video-EEG monitoring may be able to
provide a conclusive diagnosis in patients who still have diagnostic challenges
following clinical evaluation and standard EEG, particularly if the episode
frequency is high22. The history and neurological examination serve as the fundamental basis
for the diagnosis of seizures and epilepsy, while laboratory testing is utilized
as supplementary measures. The historical features that are significant include
the clinical setting in which the seizure took place, which encompasses
premonitory indications, as well as the seizure’s specific characteristics,
such as phenomenology, responsiveness, focal features, and the post-ictal
state. Subsequent inquiry is directed towards ascertaining the presence of
an epilepsy syndrome, which serves to delineate the nature and extent of the
assessment, as well as to establish the appropriate course of treatment and
prognosis. The neurological exam evaluates localized indications that may implicate
or locate cerebral disease. Increased tone on one side of the body, for
example, could suggest pathology in the contralateral hemisphere, such us
cortical dysplasia. A general physical examination is also necessary to assess
whether or not the patient has an underlying ailment. Atypical skin marks,
for example cough suggest a neurocutanous illness characterized by epilepsy,
such as tuberous sclerosis or neurofibromatosis23. Diagnostic evaluation Electroencephalogram (EEG): an EEG is a recording of the electrical
activity of the brain. It is capable of detecting aberrant electrical activity
such as focal spikes or waves (which are compatible with focal epilepsy) or
diffuse bilateral spike waves (which are consistent with generalized epilepsy). Because the prevalance of epileptiform abnormalities changes in the distinct
states of consciousness, routine EEG should cover wakefulness, drowsiness,
and sleep. Hyperventilation and photic stimulation are EEG activation
procedures used to increase the yield of epileptic activity. The clinical
information is used to make and epilepsy diagnosis and the EEG should be
considered confirming rather than diagnostic. The conventional wisdom is
to “treat the patient, not the EEG.” Absence epilepsy is an exception to this
rule, as brief generalized bursts of spike-wave activity, even if not linked with
evident clinical alterations, indicate a significant likelihood of unreported
absence seizure recurrences24. Electroencephalogram (EEG): an EEG is a recording of the electrical
activity of the brain. It is capable of detecting aberrant electrical activity
such as focal spikes or waves (which are compatible with focal epilepsy) or
diffuse bilateral spike waves (which are consistent with generalized epilepsy). 169 Yavuz Yücel / Nor Osman Sidow Metabolic evaluation: seizures are frequently associated with other
anomalies in metabolic diseases, such as developmental delay, unexpected
vomiting, or unconsciousness. A metabolic study is required in neonatal
convulsions, including a screening of serum amino acids and urine organic
acids, as well as blood lactate to rule out mitochondrial dysfunctions. Cerebrospinal fluid can examine for glucose transporter abnormalities
(LUT1 deficient syndrome) in addition to its more usual usage to evaluate
CNS illness. Immunology: The identification of encephalopathies and epilepsies that
were previously unknown has been made possible by the discovery of
neuronal antibodies. The prevalence of autoimmune epilepsy is currently
uncertain; however, it seems to affect a considerable proportion of patients
with focal epilepsy. The most commonly observed etiologies of encephalitis
are antibodies directed against glutamic acid decarboxylase (GAD)-65,
LGI1, CASPR2, and NMDA receptors. This is particularly true when the
initial assessment fails to reveal an underlying cause and the patient presents
with symptoms or indications of limbic encephalitis. Diagnostic indicators
include cognitive decline, personality changes, autonomic seizures,
dyskinesia, comorbid autoimmune conditions, and mesial temporal MRI
alterations that may potentially progress to mesial temporal sclerosis. Diagnostic evaluation Imaging: The predominant modality for imaging is magnetic resonance
imaging (MRI), which discloses epileptogenic lesions in nearly 20% of
recently diagnosed epilepsy patients and over 50% of those with drug-
resistant focal epilepsy. In contrast to individuals without an MRI lesion,
those with an MRI lesion exhibit a greater likelihood of recurrence following
a first seizure or persistent seizure activity after treatment. The MRI protocol
necessitates the incorporation of volumetric T1-weighted imaging in three
dimensions with a minimum slice thickness of 1mm. Additionally, the
protocol must include axial and coronal T2-weighted and fluid attenuated
inversion recovery sequences, which should encompass hippocampal
angulation. Furthermore, the protocol should comprise axial hemosiderin
or calcification-sensitive T2 sequences or susceptibility-weighted sequences. Epileptic syndromes The contemporary classification system has incorporated the epilepsy
syndrome as a novel component. The term refers to a constellation of
symptoms that typically co-occur, encompassing various types of seizures,
electroencephalogram (EEG) readings, and imaging results. Epilepsy
syndrome is influenced by various factors such as age of onset, remission, A General Overview of Epilepsy: its Classification, and Management 170 triggers, diurnal variation, intellectual and psychiatric dysfunction, EEG
findings, imaging studies, familial history, and genetic predisposition. The
International League Against Epilepsy (ILAE) has not officially categorized
a comprehensive list of epileptic syndromes. Nevertheless, recognized and
established syndromes have been delineated and a selection of them is
examined herein. For a comprehensive inventory of epilepsy syndromes, it
is recommended to consult the website of the International League Against
Epilepsy (ILAE). In the past, the term “benign” was utilized to classify
certain epilepsy syndromes. However, this terminology is no longer favored
as it suggests that the epilepsy has negligible effects on the patient. Presently,
it is acknowledged that all types of epilepsy can have social implications and
may be linked to comorbidities such as psychiatric and learning disorders. Presently, the phrase “self-limiting” is employed. Idiopathic or Genetic Generalized Epilepsy Syndromes: The category of idiopathic generalized epilepsies encompasses various
types of seizures, including childhood absence epilepsy, juvenile absence
epilepsy, juvenile myoclonic epilepsy, and generalized tonic-clonic seizures
occurring in isolation (as presented in table 4). The utilization of the term
idiopathic in the classification of epilepsy has been a subject of controversy,
with some advocating for its removal. The term “idiopathic” was originally
coined to connote a self-originating or genetically determined condition. There exists a concern regarding the use of the term “genetic” as it may
connote inheritance, while a significant proportion of epilepsy patients
exhibit de novo mutation or complex genetic syndromes that may manifest
with or without environmental exposure. The ILAE task force has resolved
to maintain the usage of the term “idiopathic generalized epilepsy” to
denote the epilepsies mentioned earlier, owing to the preference of a
significant number of stakeholders in the epilepsy domain to retain its usage. In cases where a clinician has identified a specific genetic cause, the term
“genetic generalized epilepsy” may be employed to characterize the epilepsy
syndrome. Patients diagnosed with idiopathic generalized epilepsies exhibit
typical electrographic background and generalized spike-wave patterns in
their EEGs. Childhood absence epilepsy is a condition that is known to be self-limiting
and has a higher incidence rate in neurologically normal females as compared
to males. Onset of the condition is commonly observed to manifest between
the ages of 4 and 10, while remission is typically observed to occur during
the period of adolescence. Patients exhibit episodes of absence seizures and
occasionally experience tonic-clonic generalized seizures. The premature 171 Yavuz Yücel / Nor Osman Sidow | 17 manifestation of generalized tonic-clonic seizures is linked to a poorer
prognosis.27. Juvenile absence epilepsy manifests during the period of adolescence and
early adulthood, with the most favorable age of onset ranging from 10 to 13
years. Both genders are equally affected by absence seizures, although these
occur less frequently in childhood than absence epilepsy. At the outset of the
presentation, there is a manifestation of generalized tonic-clonic seizures,
and albeit infrequent, myoclonic seizures may also transpire. In contrast to
infantile absence epilepsy, the aforementioned syndrome is not characterized
by a self-limiting course. One of the most prevalent epilepsy syndromes is juvenile myoclonic
epilepsy, the onset period spans from before the age of 10 through the
middle of the 20s, and occasionally later. Women are more likely than men to
develop juvenile myoclonic epilepsy28. Idiopathic or Genetic Generalized Epilepsy Syndromes: Every patient experiences myoclonic
seizures, which are frequently followed by generalized tonic-cloni seizures. Rarely do absence seizures happen, most patients don’t go into spontaneous
remission and need to take antiepileptic drugs for the rest of their lives. The hallmark of piously with generalized tonic-clonic seizures only
is characterized by generalized tonic-clonic seizures that occur within an
age range spanning from childhood to mid-adulthood, with a peak onset
typically observed during the second decade of life. The term “generalized
tonic-clonic seizures at awakening” was initially used, but was later revised
upon the recognition that seizures could occur at any point during the day. Generalized tonic-clonic seizures in epilepsy, as well as juvenile absence
epilepsy and juvenile myoclonic epilepsy, are not inherently self-limiting
conditions. As a result, individuals with these forms of epilepsy often require
lifelong treatment with antiepileptic medication.29. 172 | A General Overview of Epilepsy: its Classification, and Management Tabel 4: Idiopathic or Genetic Epilepsy Syndromes
Epilepsy
Syndrome
Seizure
types
Age of
onset
Self-
limiting
EEG findings
Childhood
Absence
Epilepsy
Absence
generalized
tonic-clonic
seizure (rare)
4 to 10 years
Yes
Normal background,
occipital intermittent
rhythmic delta activity,
3-3.5Hz generalized spike
wave discharges
Juvenile
Absence
Epilepsy
Absence
generalized
tonic-clonic
seizure,
myoclonic
(rare)
adolescence
to early
adulthood
No
Normal background,
polyspikes may be present,
-3.5Hz generalized spike
wave discharges
juvenile
Myoclonic
Absence
myoclonic,
generalized
tonic-clonic,
absence (rare
10 years to
mid-20s
No
Normal background,
-3.5Hz generalized spike
wave discharges, > 4Hz
generalized spike wave
discharges, high amplitude
polyspike wave discharges
with myoclonic seizures,
photoparoxysmal response
in up to 40% of patients
Epilepsy with
generalized
tonic-clonic
seizures alone
generalized
tonic-clonic
childhood
to mid-
adulthood
No
Normal background,
generalized, spike or
polyspike wave discharges, Tabel 4: Idiopathic or Genetic Epilepsy Syndromes Focal Epilepsy Syndromes Focal epilepsy disorders such as childhood epilepsy with centro-temporal
spikes and Panayiotopoulos syndrome have been extensively documented. Formerly, the condition known as childhood epilepsy was referred to as
benign epilepsy with centro-temporal spikes (as presented in Table 5). Childhood epilepsy with centro-temporal spikes is a type of epilepsy that is
self-limited. It typically presents during the school years and is characterized
by short focal motor hemifacial seizures and nocturnal focal motor
seizures that eventually develop into bilateral tonic-clonic seizures. The
occurrence of centro-temporal spikes during sleep is in accordance with the
electroencephalogram (EEG) background. Panayiotopoulos syndrome is a
type of self-limited epilepsy that is distinguished by focal autonomic seizures
that are often prolonged, as well as focal occipital high-amplitude sleep- 173 Yavuz Yücel / Nor Osman Sidow activated spikes on the electroencephalogram (EEG). Possible autonomic
symptoms include vomiting, pallor, mydriasis, as well as symptoms related
to the digestive, respiratory, and thermoregulatory systems. Additionally,
incontinence and hypersalivation may also be observed. Reflex Epilepsy Syndromes: Reflex epilepsy syndromes refer to a type of epilepsy in which the
occurrence of seizures is triggered by a specific stimulus. Whilst generalized
tonic-clonic seizures are the most commonly occurring type of seizure,
it is important to note that other types of generalized seizures may also
manifest. Focal seizures may occasionally present as reflex epilepsy. The most
commonly occurring reflex epilepsy syndromes are those that are triggered
by photosensitivity. Two additional types of epilepsy that fall under the
category of reflex epilepsy are reading epilepsy and startle epilepsy30. Table 5: Examples of epilepsy syndromes according to age of onset: Neonatal • Benign familial neonatal epilepsy (BFNE)
Infancy • West syndrome • Dravet syndrome
Childhood • Generalized epilepsy with febrile seizures plus (GEFS+) • Childhood absence epilepsy • Lennox-Gastaut syndrome • Landau-Kleffner syndrome
Adolescence and adulthood • Landau-Kleffner syndrome Adolescence and adulthood • Juvenile myoclonus epilepsy Disorders that mimic epilepsy According to their clinical presentation or medical history, many
paroxysmal behaviors resemble epileptic seizures. Here, a few of the more
typical illnesses are mentioned, it is critical to distinguish between epileptic
and non-epileptic behaviors since some non-epileptic phenomenon can be
treated with drugs other than EDs and others only need reassurance or
avoidance of the situationsthattrigger the spell31. 174 | A General Overview of Epilepsy: its Classification, and Management Non-epileptic Seizures (NES): NES are episodic changes in motor function
or behavior that bear resemblance to epileptic seizures, but do not exhibit
any corresponding electroencephalogram (EEG) activity. These events are
commonly referred to as psychogenic seizures or pseudo-seizures, as they
differ from epileptic seizures. The condition known as NES has the potential
to cause significant impairment and is often associated with underlying
psychopathological conditions. The manifestation of the medical condition,
namely seizure, is a genuine occurrence. However, as abnormal neural
discharges are not involved, the primary objective of therapy is to target the
fundamental psychological issues. This statement provides reassurance to
both the patient and their family. Breath-Holding Spells (BHS): BHS are not voluntary responses but rather
involuntary reflexes, despite their name. BHS are at their peak in preschoolers
and are often gone by the time children reach the school age. There are two
subtypes of BHS: cyanotic and pallid. Cyanotic BHS is also referred to as
cyanotic infantile syncope, while pallid BHS is often referred to as reflex
anoxic seizures. Anger and irritation are two of the most prominent triggers
for cyanotic BHS, which is the more prevalent form. Thee kid will stop
breathing (in expiration), get cyanotic, and lose consciousness while they are
weeping, whichisthedefining characteristics of this conditon. A pallid BHS is
more prone to become agitated in response to a frightening experience or an
unpleasant stimulation (such as a minor form of trauma). After a gasp, the
patient will experience loss of consciousness, as well as pallor, bradycardia,
diaphoresis, and limpness. Neither a type of BHS is associated with and
increased predisposition to epilepsy, although seizure activity can occur at
the end of a BHS. Syncope: History is generally enough to tell the difference between
syncope (fainting) and an epileptic seizure. Lightheadedness, blurred vision,
pallor, nausea, and diaphoresis are all possible pre-attack warning indicators
(presyncopal symptoms). Disorders that mimic epilepsy Loss of consciousness and a gradual descent to the
ground follow these wringing sings, in contrast to the sudden collapse seen
in myoclonic and atonic seizures. When compared to the extended postictal
state that follows and epileptic seizure, consciousness returns relatively
quickly. Syncope is caused by a temporary drop in blood flow to the brain. This can be caused by an irregular heartbeat (arrhythmia) a condition called
orthostasis or Valsalva, or a vasovagal response (fear, pain, or mental upset). Parasomnias: are problems with sleep that can look like seizures. Night
terrors are a common parasomnia that happens to kids between the ages
of 18 months and 8 years. In early (non-REM) sleep, the child wakes up 175 Yavuz Yücel / Nor Osman Sidow screaming, sweating, and moving his or her arms and legs out of sync. The
children then goes back to sleep and doesn’t remember what happened. Night terrors are often passed down from generation to generation. The case
history is use to make the diagnosis; video-EEG is rarely needed. Nightmares
which happen during REM sleep, and nighttime epileptic seizures that start
in the frontal lobe are the main things that make a diagnosis difficulty. General approach of epilepsy management The primary mode of treatment for individuals diagnosed with epilepsy
involves the administration of anti-seizure medications. The objective is to
promptly terminate seizures while avoiding any adverse effects that may
potentially compromise the individual’s standard of living. By utilizing a
pharmacological arsenal comprising over 20 medications, it is possible to
achieve effective treatment in up to 70% of individuals who have received
a recent diagnosis of epilepsy32. Pharmaceutical agents employed in the
management of epilepsy function by impeding neuronal depolarization
through the blockade of sodium or calcium channels, augmenting the activity
of potassium channels, inhibiting glutamate-mediated neuronal excitation,
or enhancing the inhibitory effects of gamma-aminobutyric acid (GABA)
on neuronal activity. The efficacy of medications varies depending on the
underlying etiology as they operate through distinct mechanisms. Patients
with idiopathic conditions are more likely to experience improvement,
particularly if their developmental and neurological assessments yield normal
results33. The selection of a particular seizure medication by a neurologist is
contingent upon various factors such as the nature of the seizure, the age
of the patient, and the coexistence of other medical ailments. Furthermore,
the potential adverse effects of the intervention should be taken into
consideration. Oftentimes, a medication with a wide range of efficacy is
employed due to the possibility of an insufficient description of a seizure
provided by a witness. Levetiracetam has become increasingly favored
as a primary treatment option in recent times owing to its effectiveness,
convenient dosage adjustment, and established adverse effects profile. In the
past, carbamazepine was the favored therapeutic option for focal seizures,
whereas valproic acid was the preferred treatment for generalized seizures. Typically, it is advisable to administer an initial modest dosage of
medication in order to mitigate the likelihood of adverse effects. In the
event of a need for escalation, incremental dosages may be administered
at predetermined intervals. The aim is to effectively control seizures while
utilizing the minimum feasible dosage. A trial that is deemed appropriate
entails a duration of two months during which a therapeutic dosage is A General Overview of Epilepsy: its Classification, and Management 176 administered and well-tolerated.34. The possibility of increased toxicity
resulting from drug interactions is a potential concern in combination
therapy. Nevertheless, specific combinations, such as lamotrigine and
valproic acid, have demonstrated notable efficacy in treating generalized
seizures (refer to table 6). General approach of epilepsy management The central nervous system (CNS) adverse effects
are a common occurrence among anticonvulsant drugs, owing to their
respective mechanisms of action. As an illustration, drowsiness is a prevalent
unfavorable outcome of almost all antiepileptic drugs (refer to table 7). Certain medical practitioners may consider the possibility of discontinuing
a particular medication in the event that seizures have not manifested for
a minimum duration of two years. In cases where medication proves to
be ineffective in managing seizures, alternative options such as dietary
therapy (ketogenic diet), epilepsy surgery (lesionectomy, hemispherotomy),
and palliative epilepsy surgery (stimulation therapy,callosotomy) may
be considered35. Modifying one’s lifestyle is an essential element of the
management of epilepsy. Improving epilepsy outcome can be achieved
through the optimization of sleep, enhancement of medication adherence,
and minimization of stress. Ultimately, it is imperative that individuals in
good health advocate for those who are experiencing digestive wellness. Individuals diagnosed with epilepsy encounter considerable obstacles
to achieving a typical way of life as a result of the negative attitudes and
prejudicial treatment they encounter. a Low: <50%; intermediate: 50% to 85%; high: >85%. b Short: <10 hours; intermediate: 10 to 30 hours; long: >30 hours. General approach of epilepsy management Yavuz Yücel / Nor Osman Sidow | 177 Table 6: Range of efficacy and chose of Antiepileptic Drugs
Antiepileptic
Drug
Focal
seizures
Generalized
tonic-clonic
seizures
generalized
absence
seizures
generalized
myoclonic
seizures
Len-
nox-Gastaut
syndrome/In-
fantile spasm/
Dravetsyn-
dorme
Phenobarbital
Class 1 trial Suggested,
but not
proven in
Class 1 trails
Not effective
Class 1V
evidence
Phenytoin
Class 1 trial Suggested,
but not
proven in
Class 1 trails
Not effective
Not effective
Carbamazepine Class 1 trial Suggested,
but not
proven in
Class 1 trails
Not effective
Not effective
Oxcarbazepine
Class 1 trial Unknown
Not effective
Not effective
Eslicarbazepine
acetate
Class 1 trial Unknown
Not effective
Not effective
Valproate
Class 1 trial Suggested,
but not
proven in
Class 1 trails
Class 1 trial
Suggested, but
not proven in
Class 1 trails
Suggested, but
not proven in
Class 1 trails
Ethosuzimide
Not
effective
Not effective
Class 1 trial
Not effective
Class 1 trial
Lennox-Gastaut
syndrome
Clobazam
Suggested,
but not
proven in
Class 1
trails
Suggested,
but not
proven in
Class 1 trails
Suggested, but
not proven in
Class 1 trails
Suggested, but
not proven in
Class 1 trails
Class 1 trial
Lennox-Gastaut
syndrome
Felbamate
Class 1 trial Suggested,
but not
proven in
Class 1 trails
Unknown
Unknown
Gabapentin
Class 1 trial Not effective
Not effective
Not effective
Pregabalin
Class 1 trial Not effective
Not effective
Not effective
Lamotrigine
Class 1 trial Class 1 trial
Suggested, but
not proven in
Class 1 trials
Variable
Class 1 trial
Lennox-Gastaut
syndrome
Topiramate
Class 1 trial Class 1 trial
Not effective
in Class 1 trial
Unknown
Class 1 trial
Lennox-Gastaut
syndrome
Tiagabine
Class 1 trial Not effective
Not effective
Not effective
Levetiracetam
Class 1 trial Class 1 trial
Suggested, but
not proven in
Class 1 trials
Class 1 trial
Brivaracetam
Class 1 trial Unknown
Unknown
Unknown Table 6: Range of efficacy and chose of Antiepileptic Drugs 78 | A General Overview of Epilepsy: its Classification, and Management 178 Zonisamide
Class 1 trial Suggested,
but not
proven in
Class 1 trails
Suggested, but
not proven in
Class 1 trials
Suggested, but
not proven in
Class 1 trials
Lacosamide
Class 1 trial Unknown
Not effective
Not effective
Vigabatrin
Class 1 trial Not effective
Not effective
Not effective
Class 1 trial
Infantile Spasm
Rufinamide
Class 1
trial, but
not FDA
approved
Suggested,
but not
proven in
Class 1 trails
Unknown
Unknown
Class 1 trial
Lennox-Gastaut
syndrome
Perampanel
Class 1 trial Class 1 trial
Unknown
Class IV
evidence
Cannabidiol
Class IV
evidence
Unknown
Unknown
Unknown
Class 1 trial
Lennox-Gastaut
syndrome/
Infantile Spasm
Table 7: Pharmacokinetic aspects of Antiepileptic Drugs
Antiepileptic drug
Oral
bioavailability
Protein
bindinga
Metabolism
Half-lifeb
Drug
interaction
Phenobarbital
Good
Low
>70%
Long
High
Phenytoin
Variable
High
Extensive
not linear
Intermediate
(long with
toxicity)
High
Carbamazepine
Good
Intermediate
Extensive
Intermediate
High
Oxcarbazepine
Good
Low
Extensive
Short
Moderate
Eslicarbazepine
acetate
Good
Low
~40%
Intermediate
Moderate
Valproate
Good
High
Extensive
Intermediate
High
Ethosuzimide
Good
Low
Extensive
Long
Moderate
Clobazam
Good
High
Extensive
Intermediate
High
Felbamate
Good
Low
~50%
Intermediate
High
Gabapentin
Low
Low
None
Short
No/minimal
Pregabalin
Good
Low
None
Short
No/minimal
Lamotrigine
Good
intermediate
Extensive
Intermediate
Moderate
Topiramate
Good
Low
~30%
Intermediate
No/minimal
Tiagabine
Good
High
Extensive
Short
High
Levetiracetam
Good
Low
~30% non-
hepatic
Short
No/minimal
Brivaracetam
Good
Low
Extensive
Short
Moderate
Zonisamide
Good
Low
~65%
Short
Moderate
Lacosamide
Good
Low
~60%
Intermediate
No/minimal
Vigabatrin
Good
Low
None
Intermediate
No/minimal
Rufinamide
Good
intermediate
Extensive
Short
Moderate
Perampanel
Good
High
Extensive
Long
Moderate
Cannabidiol
Low
High
Extensive
Long
HIgh Zonisamide
Class 1 trial Suggested,
but not
proven in
Class 1 trails
Suggested, but
not proven in
Class 1 trials
Suggested, but
not proven in
Class 1 trials
Lacosamide
Class 1 trial Unknown
Not effective
Not effective
Vigabatrin
Class 1 trial Not effective
Not effective
Not effective
Class 1 trial
Infantile Spasm
Rufinamide
Class 1
trial, but
not FDA
approved
Suggested,
but not
proven in
Class 1 trails
Unknown
Unknown
Class 1 trial
Lennox-Gastaut
syndrome
Perampanel
Class 1 trial Class 1 trial
Unknown
Class IV
evidence
Cannabidiol
Class IV
evidence
Unknown
Unknown
Unknown
Class 1 trial
Lennox-Gastaut
syndrome/
Infantile Spasm Table 7: Pharmacokinetic aspects of Antiepileptic Drugs
Antiepileptic drug
Oral
bioavailability
Protein
bindinga
Metabolism
Half-lifeb
Drug
interaction
Phenobarbital
Good
Low
>70%
Long
High
Phenytoin
Variable
High
Extensive
not linear
Intermediate
(long with
toxicity)
High
Carbamazepine
Good
Intermediate
Extensive
Intermediate
High
Oxcarbazepine
Good
Low
Extensive
Short
Moderate
Eslicarbazepine
acetate
Good
Low
~40%
Intermediate
Moderate
Valproate
Good
High
Extensive
Intermediate
High
Ethosuzimide
Good
Low
Extensive
Long
Moderate
Clobazam
Good
High
Extensive
Intermediate
High
Felbamate
Good
Low
~50%
Intermediate
High
Gabapentin
Low
Low
None
Short
No/minimal
Pregabalin
Good
Low
None
Short
No/minimal
Lamotrigine
Good
intermediate
Extensive
Intermediate
Moderate
Topiramate
Good
Low
~30%
Intermediate
No/minimal
Tiagabine
Good
High
Extensive
Short
High
Levetiracetam
Good
Low
~30% non-
hepatic
Short
No/minimal
Brivaracetam
Good
Low
Extensive
Short
Moderate
Zonisamide
Good
Low
~65%
Short
Moderate
Lacosamide
Good
Low
~60%
Intermediate
No/minimal
Vigabatrin
Good
Low
None
Intermediate
No/minimal
Rufinamide
Good
intermediate
Extensive
Short
Moderate
Perampanel
Good
High
Extensive
Long
Moderate
Cannabidiol
Low
High
Extensive
Long
HIgh
a Low: <50%; intermediate: 50% to 85%; high: >85% Table 7: Pharmacokinetic aspects of Antiepileptic Drugs Yavuz Yücel / Nor Osman Sidow | 179 Yavuz Yücel / Nor Osman Sidow | 179 Status Epilepticus Status epilepticus (SE) is considered to be one of the most critical
neurological emergencies. It is characterized by prolonged or recurrent
seizures that do not allow the individual to fully return to their baseline state. Based on estimates, there exists a range of 10-40 cases and a corresponding
mortality rate per 100,000 individuals, approximately 20% of whom
experience a return to previous levels of functionality at a rate of only one-
third.36. In 2015, the ILAE Task Force on Classification of Status Epilepticus
emphasized the significance of timing in the assessment of seizures. The
International League Against Epilepsy (ILAE) introduced two operational
dimensions that pertain to the duration of a seizure. These dimensions
are defined by the period of epileptic activity that may lead to permanent
brain damage with long-term consequences, and the duration beyond
which a seizure should be identified as unusually prolonged. According
to findings from studies conducted on both animals and humans, it has
been projected that the anticipated time intervals for convulsive tonic-clonic
status epilepticus (SE) are 5 minutes and 30 minutes, correspondingly. The available data on non-convulsive status epilepticus (NCSE) is limited
as most studies have primarily focused on convulsive forms. However, the
International League Against Epilepsy (ILAE) has recommended time
points of 10 minutes (t1) and 60 minutes (t2) for focal status epilepticus
with impaired consciousness37. The extant guidelines and protocols for the management of status
epilepticus (SE) prescribe specific timing recommendations for each line of
therapy. These recommendations stipulate that first-line treatment should
be administered within the initial 10 minutes of seizure activity, second-
line treatment within the initial 20 minutes, and third-line treatment should
be considered if SE persists despite the administration of at least two
anti-seizure medications (ASM) with optimal dosing within the initial 60
minutes. Several studies and meta-analyses have concurred that there exist
systematic delays in the treatment of SE when compared to the recommended
guidelines (refer to Table 8). Current guidelines recommend several pharmacological treatments for
SE. initial administration of benzodiazepines recommend occurs in the
earliest prehospital phases of seizures, in the early phase of an established
SE, anticonvulsant medications are administered intravenously (IV) after
hospital admission (table 9a and 9b). If IV ASM administration fails to
control refractory seizures, general anesthesia is administered, such as by 180 A General Overview of Epilepsy: its Classification, and Management IV infusion of midazolam, propofol, or ketamine. Status Epilepticus Continuous infusion of
anesthetics is administered until the seizure subsidies and is continued for
12-24 hours after the last seizure. If SE persists or recurs despite the use of
anesthetic for at least 24 hours, it is defined as super-refractory SE (SRSE)38. Table 8: General approach of Status epilepticus management Table 8: General approach of Status epilepticus management Table 8: General approach of Status epilepticus management
General Measures
Medications
Immediate
Management
(0-5 minutes)
Note the time, call for
help
Secure airway (semi-
prone position,
nasopharyngeal airway),
give oxygen
IV cannulation, finger
glucose, blood gas, LFT,
RFT, electrolytes, AED
levels, CRP
History: past
medications, overdose
and drug addiction
Observe prehospital
treatment
Give thymine if
suspected of Alcohol
excess
Dextrose infusion if
hypoglycemic
Benzodiazepines for
IV preparations
Early Status
Epilepticus
(5-20 minutes)
Monitoring vital signs
Cardiac monitoring
ICU possibility
give benzodiazepines if no
response repeat after 5 minutes
Established
Status
Epilepticus
(20-40 minutes)
ICU review
chest x ray
CT head
Consider intubation
Give 2nd line AEDs
Phenytoin/
Fosphenytoin
Sodium valproate
Levetiracetam
Refractory
Status
Epilepticus
(>30 mins)
Intubate and admit ICU
continuous EEG
monitoring
Anesthetic agents like
(Thiopental, propofol,
midazolam) Table 9: Doses of first-line and second-line ASM for SE
Table 9a: Benzodiazepines as first-line in SE
Intravenous
Non-intravenous
Lorazepam 0.1mg/kg (max 4mg)
Midazolam IM/IN/buccal 10mg
5mg in elderly or <40kg
Diazepam 0.15-2mg/kg (max 10mg)
Diazepam 10mg rectal
5mg in elderly or <40kg
Clonazepam 0.015mg/kg (max 1mg)
Lorazepam intranasal
0.1mg/kg or <40kg Table 9: Doses of first-line and second-line ASM for SE 181 Yavuz Yücel / Nor Osman Sidow | 181 Table 9b: Second line of ASMs in SE
Drug
Dose; Rate,
Maximum
Suggestion
Caution
Phenytoin/
Fosphenytion
20mg/kg
50g/min
(2000mg)
Already taking
phenytoin. Suspected poor
adherence
•
significant hypotension
•
bradycardia, heart block
•
Porphyria
•
generalized Epilepsy
•
Overdose of recreation
drugs or antidepressants
Valproate
30mg/kg
10mg/kg/min
(3000mg)
Already taking
Valproate. Suspected poor
adherence
generalized
epilepsy
•
women of childbearing
age
•
pre-existing of liver disease
or pancreatitis
•
known metabolic disorder
•
caution in acute stroke or
brain injury
Levetiracetam
60mg/kg
6mg/kg/min
(4500mg)
Already taking
Levetiracetam,
Suspected poor
adherence
•
acute or brain injury
•
known mood/behavioral
disorder
•
renal impairment Table 9b: Second line of ASMs in SE Women and epilepsy The occurrence of seizures and the administration of antiepileptic
medications have the potential to interfere with hormone regulation, thereby
posing a threat to the sexual and reproductive well-being of women diagnosed
with epilepsy. Women diagnosed with epilepsy encounter social stigmatization
in several developing nations. According to a study conducted by Komolafe
et al. (2012), the economic status of WWE in Nigeria is comparatively lower
than that of non-epileptic women.39. According to Santosh et al. (2007),
a significant proportion of individuals with epilepsy in India concealed
their condition from their prospective spouses due to apprehension of
social ostracism and the possibility of disrupted marriage negotiations. Specifically, over 50% of individuals with epilepsy who participated in the
study reported hiding their condition prior to marriage40. Women with
epilepsy typically experience a higher frequency of seizures during periods
of hormonal fluctuations such as puberty, menstruation, pregnancy, and
menopause. Catamenial epilepsy exacerbates seizures during menstruation
in females with epilepsy. The prevalence of catamenial epilepsy among
women with epilepsy (WWE) ranges from 33% to 50%. The works cited are
those of Foldvary-Schaefer and Falcone (2003) and Morrell (1999).41. The A General Overview of Epilepsy: its Classification, and Management 182 prevalence of menstruation issues in WWE was found to be 2.5 times higher
than that of the general population. The occurrence of epilepsy in relation to
the menstrual cycle, known as catamenial epilepsy, has been found to have
a correlation with the varying levels of hormones, particularly estrogen and
progesterone. It has been observed that progesterone exhibits anticonvulsant
properties while estrogen has proconvulsant effects. The condition known as
catamenial epilepsy exhibits three discernible patterns of heightened seizure
frequency, namely C1 (perimenstrual pattern), C2 (perovulatory pattern),
and C3 (luteal pattern). C1 takes place in the follicular phase, which spans
from day 4 to day 10 of the menstrual cycle. C2 occurs during the ovulatory
phase, which takes place from day 10 to day 14 of the cycle. Finally, C3
occurs in the luteal phase, which spans from day 17 to day 3 of the menstrual
cycle. According to research conducted by Harden and Pennell (2013)
and Reddy, the levels of progesterone exhibit a decline during phases C1
and C3, whereas estrogen levels experience an increase during phase C242. Antiepileptic drugs (AEDs) have the potential to impact or bear resemblance
to the menstrual cycle. K intravenously to neonates born to mothers undergoing antiepileptic drug
(AED) therapy for women with epilepsy (WWE).44 K intravenously to neonates born to mothers undergoing antiepileptic drug
(AED) therapy for women with epilepsy (WWE).44 K intravenously to neonates born to mothers undergoing antiepileptic drug
(AED) therapy for women with epilepsy (WWE).44 Women and epilepsy Seizures have the potential to induce disturbances in
neuroendocrine activity, resulting in menstrual irregularities in women with
epilepsy, as well as serving as an adverse reaction of antiepileptic drugs. An
increasing body of evidence suggests that the utilization of valproate among
females is associated with a higher likelihood of encountering menstrual
irregularities, such as polycystic ovarian syndrome (PCOS). According to
Johnston and Crawford (2014), there exist bidirectional pharmacokinetic
interactions between oral contraceptives and AEDs. There exist a number
of antiepileptic drugs (AEDs) that are recognized for their ability to
induce cytochrome activity, specifically within the CYP3A4 group. Such
drugs include carbamazepine, oxcarbazepine, topiramate, phenobarbitone,
and phenytoin43. The cytochromes play a role in the metabolic process of
the primary constituents of the combined oral contraceptive pill, namely
estrogen and progesterone. Hence, the effectiveness and efficacy of oral
contraceptive pills (OCPs) could be reduced when co-administered with
cytochrome-inducing antiepileptic drugs (AEDs). According to Harden et al. (2009a), a significant proportion of women
with epilepsy (WWE) do not experience any alteration in seizure activity
during gestation compared to their pre-pregnancy baseline. This finding
is noteworthy as WWE often express apprehension regarding the efficacy
of seizure management during pregnancy. Given that AEDs are excreted in
breast milk in minimal quantities, it is commonly accepted that breastfeeding
while taking AEDs is a safe practice. According to the National Institute for
Health and Care Excellence (2012), it is recommended to administer vitamin 183 Yavuz Yücel / Nor Osman Sidow Prognosis From a demographic perspective, the majority of individuals with
epilepsy exhibit a positive prognosis. The likelihood of recurrence following
an initial seizure is subject to significant variability contingent upon whether
the seizure was characterized by acute and symptomatic features or occurred
spontaneously. In contrast to single unprovoked seizures, acute symptomatic
seizures exhibit a comparatively lower recurrence rate of approximately 19%
over a decade According to Beghi’s (2003) findings, the aggregate likelihood
of recurrence subsequent to an initial unprovoked seizure varies between 23
and 71%. Two factors that have a high likelihood of predicting return are
the presence of a known cause and an atypical EEG pattern, characterized by
epileptiform and/or slow activity45. Epilepsy is a treatable conditon, with up to 80% of people having long
times without seizures and up to 50% of people still not having seizure
after treatment stops. Patients with unexplained or cryptogenic first seizures
have shown that there is a link between having seizures again and having
them in the past. Only in LMIC, where most people with epilepsy don’t get
treatment (the treatment gab is between 70 and 94%), can be the outcome
of untreated epilepsy be determined. The cause of epilepsy is the best
prediction of whether or not seizures will happen again, in a well-defined
US community, people with symptomatic epilepsy had a much lower chance
of remission after 5 years than those with idiopathic epilepsy (42 vs. 30% at
15 years), and people with neurological dysfunction at birth had the lowest
change of remission. Type of seizure and EEG epileptiform changes were
also used to predict the outcome. Europe also had lower remission rates for
people with symptomatic epilepsy46. The chance of dying from epilepsy is
low, but when incidence and prevalence studies area compared, mortality
rates are likely to be different. When epilepsy or seizures cause death, some
of the most important causes are SUDEP, SE, accidental injury, and suicide. 184 184 | A General Overview of Epilepsy: its Classification, and Management References Osawa, S. I., Iwasaki, M., Hosaka, R., Matsuzaka, Y., Tomita, H., Ishizuka, T.,
...&Mushiake, H. (2013). Optogenetically induced seizure and the longi-
tudinal hippocampal network dynamics. PloS one, 8(4), e60928. Fisher, R. S., Boas, W. V. E., Blume, W., Elger, C., Genton, P., Lee, P., & Engel
Jr, J. (2005). Epileptic seizures and epilepsy: definitions proposed by the
International League Against Epilepsy (ILAE) and the International Bu-
reau for Epilepsy (IBE). Epilepsia, 46(4), 470-472. Falco-Walter, J. J., Scheffer, I. E., & Fisher, R. S. (2018). The new definition
and classification of seizures and epilepsy. Epilepsy research, 139, 73-79. Falco-Walter, J. (2020, December). Epilepsy—definition, classification, pathop-
hysiology, and epidemiology.In Seminars in neurology (Vol. 40, No. 06,
pp. 617-623).Thieme Medical Publishers, Inc.. Fisher, R. S., &Leppik, I. (2008). Debate: When does a seizure imply epi-
lepsy?. Epilepsia, 49, 7-12. Camfield, P., &Camfield, C. (2015). Incidence, prevalence and aetiology of sei-
zures and epilepsy in children. Epileptic disorders, 17(2), 117-123. Stafstrom, C. E., &Carmant, L. (2015). Seizures and epilepsy: an overview
for neuroscientists. Cold Spring Harbor perspectives in medicine, 5(6),
a022426. Riney, K., Bogacz, A., Somerville, E., Hirsch, E., Nabbout, R., Scheffer, I. E.,
...&Tinuper, P. (2021). ILAE classification and definition of epilepsy sy-
ndromes with onset at a variable age: position statement by the ILAE Task
Force on Nosology and Definitions. Currently in Review by the ILAE. Available online at: https://www. ilae. org/guidelines/definition-and-clas-
sification/proposed-classificationand-definition-of-epilepsy-syndromes/
proposed-classification-syndromeswith-onset-at-variable-ages (accessed
October 26, 2021). Patel, P., &Moshé, S. L. (2020). The evolution of the concepts of seizures and
epilepsy: What’s in a name?. Epilepsia Open, 5(1), 22-35. Fisher, R. S., Acevedo, C., Arzimanoglou, A., Bogacz, A., Cross, J. H., Elger,
C. E., ... & Wiebe, S. (2014). ILAE official report: a practical clinical
definition of epilepsy. Epilepsia, 55(4), 475-482. Specchio, N., Wirrell, E. C., Scheffer, I. E., Nabbout, R., Riney, K., Samia, P.,
...&Auvin, S. (2022). International League Against Epilepsy classificati-
on and definition of epilepsy syndromes with onset in childhood: Positi-
on paper by the ILAE Task Force on Nosology and Definitions. Epilep-
sia, 63(6), 1398-1442. Nashef, L., Hindocha, N., &Makoff, A. (2007). Risk factors in sudden death in
epilepsy (SUDEP): the quest for mechanisms. Epilepsia, 48(5), 859-871. 185 Yavuz Yücel / Nor Osman Sidow Brodie, M. J., Barry, S. J. E., Bamagous, G. A., Norrie, J. D., & Kwan, P. (2012). Patterns of treatment response in newly diagnosed epilepsy. Neuro-
logy, 78(20), 1548-1554. Engel, J. References (2005). Epilepsy: global issues for the practicing neurologist (Vol. 2). De-
mos Medical Publishing. Kandar, H. K. M. C. C., Das, S. K., Ghosh, L., & Gupta, B. K. (2012). Epilepsy
and its management: A review. Journal of PharmaSciTech, 1(2), 20-26. McHugh, J. C., &Delanty, N. (2008). Epidemiology and classification of epi-
lepsy: gender comparisons. International review of neurobiology, 83, 11-26. Behr, C., Goltzene, M. A., Kosmalski, G., Hirsch, E., &Ryvlin, P. (2016). Epi-
demiology of epilepsy. Revue neurologique, 172(1), 27-36. Thurman, D. J., Beghi, E., Begley, C. E., Berg, A. T., Buchhalter, J. R., Ding,
D., ... & ILAE Commission on Epidemiology. (2011). Standards for epi-
demiologic studies and surveillance of epilepsy. Epilepsia, 52, 2-26 Patel, D. C., Tewari, B. P., Chaunsali, L., &Sontheimer, H. (2019). Neuron–glia
interactions in the pathophysiology of epilepsy. Nature Reviews Neuros-
cience, 20(5), 282-297. Hirose, G. (2013). An overview of epilepsy: its history, classification, pat-
hophysiology and management. Brain and nerve= Shinkeikenkyu no
shinpo, 65(5), 509-520. Sharma, R., &Pachori, R. B. (2015). Classification of epileptic seizures in EEG
signals based on phase space representation of intrinsic mode functi-
ons. Expert Systems with Applications, 42(3), 1106-1117 Peker, M., Sen, B., &Delen, D. (2015). A novel method for automated diagno-
sis of epilepsy using complex-valued classifiers. IEEE journal of biomedical
and health informatics, 20(1), 108-118 Kutlubaev, M. A., Xu, Y., Hackett, M. L., & Stone, J. (2018). Dual diagnosis
of epilepsy and psychogenic nonepileptic seizures: systematic review and
meta-analysis of frequency, correlates, and outcomes. Epilepsy & Behavi-
or, 89, 70-78. Malmgren, K., Reuber, M., & Appleton, R. (2012). Differential diagnosis of
epilepsy. Oxford textbook of epilepsy and epileptic seizures, 81-94. Schmitt, B. (2015). Sleep and epilepsy syndromes. Neuropediatrics, 46(03),
171-180 Seneviratne, U., Cook, M. J., & D’Souza, W. J. (2017). Electroencephalography
in the diagnosis of genetic generalized epilepsy syndromes. Frontiers in
neurology, 8, 499. Zuberi, S. M., Wirrell, E., Yozawitz, E., Wilmshurst, J. M., Specchio, N., Riney,
K., ...&Nabbout, R. (2022). ILAE classification and definition of epi-
lepsy syndromes with onset in neonates and infants: Position statement 186 A General Overview of Epilepsy: its Classification, and Management by the ILAE Task Force on Nosology and Definitions. Epilepsia, 63(6),
1349-1397. Hirsch, E., French, J., Scheffer, I. E., Bogacz, A., Alsaadi, T., Sperling, M. R.,
...& Zhou, D. (2022). References ILAE definition of the idiopathic generalized epi-
lepsy syndromes: position statement by the ILAE task force on nosology
and definitions. Epilepsia, 63(6), 1475-1499. van Baalen, A., Vezzani, A., Häusler, M., &Kluger, G. (2017). Febrile infection–
related epilepsy syndrome: clinical review and hypotheses of epileptoge-
nesis. Neuropediatrics, 48(01), 005-018. Camfield, P., &Camfield, C. (2015). Incidence, prevalence and aetiology of sei-
zures and epilepsy in children. Epileptic disorders, 17(2), 117-123. Louis, E. K. S., &Cascino, G. D. (2016). Diagnosis of epilepsy and related epi-
sodic disorders. CONTINUUM: Lifelong Learning in Neurology, 22(1),
15-37. Perucca, P., Scheffer, I. E., & Kiley, M. (2018). The management of epilepsy in
children and adults. Medical Journal of Australia, 208(5), 226-233. Brown, C. (2016). Pharmacological management of epilepsy. Progress in Neuro-
logy and Psychiatry, 20(2), 27-34c Volkov, I. V., &Volkova, O. K. (2020). Juvenile myoclonic epilepsy. Upda-
te. Epilepsy and paroxysmal conditions, 12(1S), S41-S49 Nascimento, F. A., Friedman, D., Peters, J. M., Bensalem‐Owen, M. K., Cendes,
F., Rampp, S., ...&Beniczky, S. (2023). Focal epilepsies: update on diag-
nosis and classification. Epileptic Disorders Trinka, E., &Leitinger, M. (2022). Management of status epilepticus, refractory
status epilepticus, and super-refractory status epilepticus. CONTINU-
UM: Lifelong Learning in Neurology, 28(2), 559-602. Treiman, D. M. (2020). Status epilepticus.In The medical treatment of epi-
lepsy (pp. 183-194).CRC Press. Shorvon, S., & Sen, A. (2020). What is status epilepticus and what do we know
about its epidemiology?. Seizure, 75, 131-136. Komolafe, M. A., Sunmonu, T. A., Afolabi, O. T., Komolafe, E. O., Fabusiwa,
F. O., Groce, N., ... &Olaniyan, S. O. (2012). The social and economic
impacts of epilepsy on women in Nigeria. Epilepsy & Behavior, 24(1),
97-101. Santosh, D., Kumar, T. S., Sarma, P. S., & Radhakrishnan, K. (2007). Wo-
men with onset of epilepsy prior to marriage: disclose or conceal?. Epilep-
sia, 48(5), 1007-1010 Foldvary-Schaefer, N., & Falcone, T. (2003). Catamenial epilepsy: pathophy-
siology, diagnosis, and management. Neurology, 61(6 suppl 2), S2-S15. 187 Yavuz Yücel / Nor Osman Sidow Harden, C. L., & Pennell, P. B. (2013). Neuroendocrine considerations in the
treatment of men and women with epilepsy. The Lancet Neurology, 12(1),
72-83. Harden, C. L., & Pennell, P. B. (2013). Neuroendocrine considerations in the
treatment of men and women with epilepsy. The Lancet Neurology, 12(1),
72-83. Johnston, C. A., & Crawford, P. M. (2014). Anti-epileptic drugs and hormonal
treatments. Current treatment options in neurology, 16, 1-9. Harden, C. References L., Hopp, J., Ting, T. Y., Pennell, P. B., French, J. A., Allen Hau-
ser, W., ... & Le Guen, C. (2009). Management issues for women with
epilepsy—Focus on pregnancy (an evidence‐based review): I. Obstetrical
complications and change in seizure frequency: Report of the Quality
Standards Subcommittee and Therapeutics and Technology Assessment
Subcommittee of the American Academy of Neurology and the Ameri-
can Epilepsy Society. Epilepsia, 50(5), 1229-1236. Beghi, E., Gatti, G., Tonini, C., Ben-Menachem, E., Chadwick, D. W., Nikano-
rova, M., ... & BASE Study Group. (2003). Adjunctive therapy versus
alternative monotherapy in patients with partial epilepsy failing on a sing-
le drug: a multicentre, randomised, pragmatic controlled trial. Epilepsy
research, 57(1), 1-13. Shorvon, S. D., &Goodridge, D. M. (2013). Longitudinal cohort studies of
the prognosis of epilepsy: contribution of the National General Practice
Study of Epilepsy and other studies. Brain, 136(11), 3497-3510.
|
https://openalex.org/W2806677552
|
https://europepmc.org/articles/pmc5841291?pdf=render
|
English
| null |
Sotetsuflavone suppresses invasion and metastasis in non-small-cell lung cancer A549 cells by reversing EMT via the TNF-α/NF-κB and PI3K/AKT signaling pathway
|
Cell death discovery
| 2,018
|
cc-by
| 7,218
|
A R T I C L E O p e n A c c e s s ( )
OpenAccessThisarticleislicensedunderaCreativeCommonsAttribution4.0InternationalLicense,whichpermitsuse,sharing,adaptation,distributionandreproduction
in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if
changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If
material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain
permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Abstract Abstract
Epithelial-mesenchymal transition (EMT) is associated with tumor invasion and metastasis, and offers insight into novel
strategies for cancer treatment. Sotetsuflavone was isolated from Cycas revolute, which has excellent anticancer activity
in the early stages. The present study aims to evaluate the anti-metastatic potential of sotetsuflavone in vitro. Our data
demonstrated that sotetsuflavone inhibits metastasis of A549 cells, and EMT. This inhibition was reflected in the
upregulation of E-cadherin, and downregulation of N-cadherin, vimentin, and Snail. Mechanistically, our study
demonstrated that HIF-1α played an important role in the anti-metastatic effect of sotetsuflavone in non-small-cell
lung cancer A549 cells. Sotetsuflavone not only mediated VEGF expression but also downregulated VEGF and
upregulated angiostatin, and simultaneously affected the expression of MMPs and decreased MMP-9 and MMP-13
expression. More importantly, HIF-1α expression may be regulated by the inhibition of PI3K/AKT and TNF-α/NF-κB
pathways. These results suggest that sotetsuflavone can reverse EMT, thereby inhibiting the migration and invasion of
A549 cells. This process may be associated with both PI3K/AKT and TNF-α/NF-κB pathways, and sotetsuflavone may be
efficacious in the treatment of non-small-cell lung cancer. Sotetsuflavone suppresses invasion and
metastasis in non-small-cell lung cancer
A549 cells by reversing EMT via the TNF-α/
NF-κB and PI3K/AKT signaling pathway Shaohui Wang
1, Yu Yan1, Zhekang Cheng1, Yanlan Hu1 and Tongxiang Liu1 Wang et al. Cell Death Discovery (2018) 4:26
DOI 10.1038/s41420-018-0026-9 Wang et al. Cell Death Discovery (2018) 4:26
DOI 10.1038/s41420-018-0026-9 Cell Death Discovery Official journal of the Cell Death Differentiation Association Introduction patients5. Therefore, inhibition and prevention of metas-
tasis is key to the treatment of NSCLC6. Cycas revolute
possess the function of reducing fever, preventing bleed-
ing, and dissipating congestion. The chemical ingredients
of C. revolute are mainly flavonoids7,8. Sotetsuflavone was
isolated from C. revolute in our laboratory. Early experi-
mental studies revealed that sotetsuflavone can inhibit
A549 cell growth, but its mechanism remains to be
researched. Lung cancer is a malignant tumor with the highest
morbidity and mortality worldwide, with 1.38 million new
cases each year, and over one million deaths worldwide
annually1. Non-small-cell lung cancer (NSCLC) accounts
for 80–85% of lung cancers, with a 5-year survival rate of
<15%2,3. Although advancements have been made in
chemotherapy and radiotherapy, the overall survival rate
of patients has remained unchanged in recent years4. In
NSCLC patients, about 30% of patients have distant
metastasis upon diagnosis, 50–60% of patients have dis-
tant metastasis during treatment, and eventually lung
cancer metastasis can claim the lives of 80–90% of Epithelial-mesenchymal transition (EMT) is a critical
process of tumor invasion and metastasis9. Such changes
enhance tumor cell migration, metastasis, and establish-
ment of distant secondary tumors10,11. EMT is a dynamic
and complex process inseparable from the interaction
between multiple growth factors, protein molecules,
transcription factors, and the pathways they regulate12. Hypoxia-inducible factor-1α (HIF-1α) plays an important Correspondence: Tongxiang Liu (tongxliu123@hotmail.com)
1Key Lab of Ministry of Education, National Research Center on Minority
Medicine, Minzu University of China, Beijing 100081, People’s Republic of China
Edited by A. Rufini. © The Author(s) 2018 Official journal of the Cell Death Differentiation Association Page 2 of 11 Wang et al. Cell Death Discovery (2018) 4:26 Fig. 1 Sotetsuflavone inhibited migration and invasion of A549 cells. Based on the preliminary study, A549 cells were treated with 0, 32, 64, 128
μmol/L, and 10 μg/ml of CDDP for 24 h. a Wound-healing assay measured the migration ability changes. Original magnification ×40. b Transwell-
matrigel invasion assay measured changes in invasive ability. Original magnification ×100. The results from three independent experiments were
expressed as mean ± SD compared with the control group, **P < 0.01, ***P < 0.001. Combined with pre-experimental basis and the results of
migration and invasion experiments, we finally selected 24 h as the follow-up experimental treatment time. The subsequent experimental
concentration adjusted to was 0, 64, and 128 μmol/L Fig. 1 Sotetsuflavone inhibited migration and invasion of A549 cells. Based on the preliminary study, A549 cells were treated with 0, 32, 64, 128
μmol/L, and 10 μg/ml of CDDP for 24 h. a Wound-healing assay measured the migration ability changes. Original magnification ×40. b Transwell-
matrigel invasion assay measured changes in invasive ability. Original magnification ×100. The results from three independent experiments were
expressed as mean ± SD compared with the control group, **P < 0.01, ***P < 0.001. Combined with pre-experimental basis and the results of
migration and invasion experiments, we finally selected 24 h as the follow-up experimental treatment time. The subsequent experimental
concentration adjusted to was 0, 64, and 128 μmol/L accompanied
by
an
increase
in
the
expression
of
mesenchymal cell markers vimentin, N-cadherin, and
fibronectin. Accordingly, this contributes to the occur-
rence of EMT processes, leading to the initiation of
metastasis20,21. After tumor cell hypoxia, the expression of
invasion-related proteins, such as snail, slug, fibronetin,
and vimentin increased, while E-cadherin decreased22. Moreover,
the
invasion
ability
of
tumor
cells
was
enhanced. The tumor was prone to distant metastasis and
had a deeper depth of tumor invasion22. The active
phosphorylated NF-κB in the nucleus can bind to the
promoter region of the Snail-1α gene via chromatin,
which becomes the upstream activator of Snail-1α23. TNF-α can be activated by the NF-κB pathway and induce
snail expression23. © The Author(s) 2018 Tumor necrosis factor-α
(TNF-α) is an important cytokine that participates in
inflammation, and the dynamic balance of immune cells
and tumor progression17. NF-κB and STAT3 gradually
become the core molecules involved in inflammatory-
induced metastasis in a large number of molecular sig-
naling
pathways
associated
with
inflammation
and
EMT12. Snail is a transcription factor that can stimulate
the occurrence of EMT, which is significantly upregulated
in
various
tumors
and
inhibits
the
expression
of
E-cadherin18. The reduction and deletion of E-cadherin
expression can lead to the disappearance of cell polarity
and decrease cell adhesion, and is an important marker of
the processes involved in EMT19. The expression of
E-cadherin is negatively correlated with tumor invasive-
ness, and the disappearance of epithelial cell polarity is Therefore, we evaluated the effects of sotetsuflavone on
the migration and invasion of human NSCLC cell line A549. We further explored the possible mechanism of sotetsu-
flavone against NSCLC and provided a new theoretical basis
for the treatment of lung cancer with Chinese medicine. Official journal of the Cell Death Differentiation Association © The Author(s) 2018 An imbalance in the PI3K/Akt pathway
plays a key role in the formation and development of lung
cancer, and the activation of the PI3K/Akt pathway can
activate the transduction of several downstream signals
and promote the development of NSCLC24. role in tumor cell invasion, metastasis, immortalization,
tumor angiogenesis, and cancer function13. Nuclear
factor-κB (NF-κB) usually exists in the form of a p65-p50
dimer, and can induce transcription of related genes
involved in immune responses, inflammatory responses,
cell growth, development, division, and apoptosis14. Angiogenesis and the adaptation of cells to hypoxia are
key to the development of tumors. Hypoxia can promote
angiogenesis factors, including increasing vascular endo-
thelial growth factor (VEGF), while also lowering angio-
genesis inhibitory factors such as angiostatin15. Matrix
metalloproteinases (MMPs) are important proteolytic
enzymes involved in the degradation of the extracellular
matrix (ECM) and basement membrane16. Their struc-
ture, function, and regulatory levels are closely linked to
tumor invasion and metastasis16. Tumor necrosis factor-α
(TNF-α) is an important cytokine that participates in
inflammation, and the dynamic balance of immune cells
and tumor progression17. NF-κB and STAT3 gradually
become the core molecules involved in inflammatory-
induced metastasis in a large number of molecular sig-
naling
pathways
associated
with
inflammation
and
EMT12. Snail is a transcription factor that can stimulate
the occurrence of EMT, which is significantly upregulated
in
various
tumors
and
inhibits
the
expression
of
E-cadherin18. The reduction and deletion of E-cadherin
expression can lead to the disappearance of cell polarity
and decrease cell adhesion, and is an important marker of
the processes involved in EMT19. The expression of
E-cadherin is negatively correlated with tumor invasive-
ness, and the disappearance of epithelial cell polarity is role in tumor cell invasion, metastasis, immortalization,
tumor angiogenesis, and cancer function13. Nuclear
factor-κB (NF-κB) usually exists in the form of a p65-p50
dimer, and can induce transcription of related genes
involved in immune responses, inflammatory responses,
cell growth, development, division, and apoptosis14. Angiogenesis and the adaptation of cells to hypoxia are
key to the development of tumors. Hypoxia can promote
angiogenesis factors, including increasing vascular endo-
thelial growth factor (VEGF), while also lowering angio-
genesis inhibitory factors such as angiostatin15. Matrix
metalloproteinases (MMPs) are important proteolytic
enzymes involved in the degradation of the extracellular
matrix (ECM) and basement membrane16. Their struc-
ture, function, and regulatory levels are closely linked to
tumor invasion and metastasis16. Official journal of the Cell Death Differentiation Association Sotetsuflavone inhibited the migration and invasion of
A549 cells Official journal of the Cell Death Differentiation Association Page 4 of 11 Wang et al. Cell Death Discovery (2018) 4:26 Fig. 3 Sotetsuflavone inhibited HIF-1α expression. a Immunofluorescence assay detected the expression of HIF-1α. Scale bar 50 μm. b Western
blotting detected HIF-1α expression. Using the same sample lysates as used for Fig. 2a, another gel (gel B) was run and probed with anti- HIF-1α. The
GAPDH loading control is from gel A, and is the same as shown in Fig. 2a. The data in the histogram represent the mean ± SD from three
independent experiments (**P < 0.01, ***P < 0.001) Fig. 3 Sotetsuflavone inhibited HIF-1α expression. a Immunofluorescence assay detected the expression of HIF-1α. Scale bar 50 μm. b Western
blotting detected HIF-1α expression. Using the same sample lysates as used for Fig. 2a, another gel (gel B) was run and probed with anti- HIF-1α. The
GAPDH loading control is from gel A, and is the same as shown in Fig. 2a. The data in the histogram represent the mean ± SD from three
independent experiments (**P < 0.01, ***P < 0.001) HIF-1α can increase the expression of MMPs and thus
promote the metastasis of malignant tumors27. MMPs
play an important role in tumor neovascularization,
tumor cell infiltration, and metastatic foci formation16. Immunofluorescence and western blot analysis demon-
strated that the expression of MMP-9 and MMP-13 was
downregulated in A549 cells treated with sotetsuflavone
(Fig. 5a). In addition, most of the MMP-9 and MMP-13
detected by the immunofluorescence assay were present
in the cytoplasm (Fig. 5b, c). Sotetsuflavone inhibited HIF-1α, VEGF, angiostatin, MMP-
9, and MMP-13 expression Sotetsuflavone inhibited HIF-1α, VEGF, angiostatin, MMP-
9, and MMP-13 expression Sotetsuflavone inhibited HIF-1α, VEGF, angiostatin, MMP-
9, and MMP-13 expression HIF-1α mediates cell response to hypoxia, and HIF-1α
protein overexpression has been reported in several solid
tumors and their metastases25. We detected HIF-1α
expression by western blot and immunofluorescence
assay and discovered that sotetsuflavone decreased HIF-
1α expression (Fig. 3a, b). HIF-1α can mediate VEGF expression, and VEGF is an
important factor in promoting angiogenesis and partici-
pating in tumor angiogenesis26. Western blotting analysis
demonstrated
that
sotetsuflavone
inhibited
VEGF
expression. Reverse transcription-PCR (RT-PCR) analysis
further demonstrated that VEGF was downregulated
in A549 cells treated with different concentrations of
sotetsuflavone for 24 h. Sotetsuflavone inhibited the migration and invasion of
A549 cells Angiostatin is an important
angiogenesis inhibitory factor; we used the immuno-
fluorescence assay to analyze the expression of angiosta-
tin. Our
results
demonstrated
that
sotetsuflavone
increased angiostatin expression. In combination with the
results shown in Fig. 3, we concluded that sotetsuflavone
could
reduce
VEGF
expression
and
downregulate
angiostatin expression by decreasing HIF-1α expression
(Fig. 4a–c). Sotetsuflavone inhibited the migration and invasion of
A549 cells The scratch test and Transwell invasion assay demon-
strated that sotetsuflavone inhibited cell migration com-
pared to the control group. The sclerosis width gradually Official journal of the Cell Death Differentiation Association Page 3 of 11 Wang et al. Cell Death Discovery (2018) 4:26 Fig. 2 Sotetsuflavone inhibited EMT in A549 cells. a The expression of E-cadherin and snail protein as shown by western blotting. One gel (gel
A) was run and blotted, and the blot was cut horizontally. The upper part was probed with anti-E-cadherin and anti-snail, and the lower part
was probed with anti-GAPDH. b The expression of snail, vimentin, and N-cadherin identified by RT-PCR. c Immunofluorescence assay detected
the expression of E-cadherin. Scale bar 50 μm. The data in the histogram represented the mean ± SD from three independent experiments
**P < 0.01, ***P < 0.001) Fig. 2 Sotetsuflavone inhibited EMT in A549 cells. a The expression of E-cadherin and snail protein as shown by western blotting. One gel (gel
A) was run and blotted, and the blot was cut horizontally. The upper part was probed with anti-E-cadherin and anti-snail, and the lower part
was probed with anti-GAPDH. b The expression of snail, vimentin, and N-cadherin identified by RT-PCR. c Immunofluorescence assay detected
the expression of E-cadherin. Scale bar 50 μm. The data in the histogram represented the mean ± SD from three independent experiments
(**P < 0.01, ***P < 0.001) Sotetsuflavone inhibited EMT in A549 cells
Sotetsuflavone significantly upregulated the expression
of E-cadherin, and downregulated the expression of N-
cadherin,
vimentin,
and
snail,
thereby
inducing
mesenchymal-epithelial transition (MET) (Fig. 2a–c). The
results demonstrated that sotetsuflavone could inhibit
the migration and invasion of A549 cells by reversing
EMT. Sotetsuflavone inhibited EMT in A549 cells increased, and sclerosis on both sides of the cell density
gradually reduced. At the same time, the scratch-healing
rate of the sotetsuflavone treatment group decreased
gradually in a dose-dependent manner (Fig. 1a). Inter-
estingly, the invasion ability of A549 cells treated with
different concentrations of sotetsuflavone was also sig-
nificantly decreased, which demonstrated a significant
dose-dependent inhibition of A549 cell invasion (Fig. 1b). Sotetsuflavone significantly upregulated the expression
of E-cadherin, and downregulated the expression of N-
cadherin,
vimentin,
and
snail,
thereby
inducing
mesenchymal-epithelial transition (MET) (Fig. 2a–c). The
results demonstrated that sotetsuflavone could inhibit
the migration and invasion of A549 cells by reversing
EMT. Official journal of the Cell Death Differentiation Association Discussion Sotetsuflavone is a type of double flavonoid extracted
from the stem and leaf of C. revolute, and has a strong
inhibitory activity on DENV-NS5 RdRp30. In preliminary
work, we have demonstrated that sotetsuflavone can
inhibit proliferation and induction of apoptosis in the
anti-human lung cancer cell line A549. Based on previous
work, we generated the hypothesis that sotetsuflavone
could inhibit the migration and invasion of A549 cells by
reversing EMT. Sotetsuflavone inhibited NF-κB pathway activation by
downregulating TNF-α NF-κB and HIF-1 are related to both gene and protein
levels, and it has been suggested that activation of NF-κB
and HIF-1α can promote angiogenesis or tumor pro-
gression28. Our results demonstrated that sotetsuflavone
decreased both TNF-α and NF-κB expression in a dose-
dependent manner (Fig. 6a, b). Combined with snail
expression in Fig. 2a, it was suggested that sotetsuflavone
can inhibit the activation of the NF-κB pathway by
downregulating TNF-α expression, which inhibited the
stability of snail protein by making it easier to degrade and
lose its regulation. Official journal of the Cell Death Differentiation Association Page 5 of 11 Wang et al. Cell Death Discovery (2018) 4:26 Fig. 4 Sotetsuflavone inhibited VEGF and angiostatin expression. a Western blotting detection of VEGF protein expression. Using the same
sample lysates as used for Fig. 2a, another gel (gel C) was run and probed with anti-VEGF. The GAPDH loading control is from gel A, and is the same
as shown in Fig. 2a. b The expression of VEGF gene detected by RT-PCR. c Immunofluorescence assay detected the expression of angiostatin. Scale
bar 50 μm. The data in the histogram represented the mean ± SD from three independent experiments (**P < 0.01, ***P < 0.001) Fig. 4 Sotetsuflavone inhibited VEGF and angiostatin expression. a Western blotting detection of VEGF protein expression. Using the same
sample lysates as used for Fig. 2a, another gel (gel C) was run and probed with anti-VEGF. The GAPDH loading control is from gel A, and is the same
as shown in Fig. 2a. b The expression of VEGF gene detected by RT-PCR. c Immunofluorescence assay detected the expression of angiostatin. Scale
bar 50 μm. The data in the histogram represented the mean ± SD from three independent experiments (**P < 0.01, ***P < 0.001) Sotetsuflavone inhibited the PI3K/AKT signaling pathway Sotetsuflavone inhibited the PI3K/AKT signaling pathway
The PI3K/AKT pathway is involved in the regulation of
HIF-1α29. Western blot analysis and RT-PCR assay
demonstrated that the PI3K/AKT pathway was inhibited
by sotetsuflavone in a dose- and time-dependent manner
along with the inhibition of HIF-1α expression (Figs. 7a, b
and 3a, b). Diagram of the proposed mechanism by which
sotetsuflavone inhibited NSCLC A549 cell invasion and
metastasis In the present study, we discovered that sotetsuflavone
can inhibit the migration and invasion of A549 cells
(Fig. 1a, b). E-cadherin, N-cadherin, and vimentin are
important marker molecules of EMT adjusted by snail31. E-cadherin mediates cell adhesion and inhibits tumor
invasion and metastasis, and tumor advancement is clo-
sely related to its deletion31. The expression of N-
cadherin in epithelial tissue changes the morphological
and biological functions of epithelial cells and trans-
forming epithelial cells into interstitial cells in the EMT
process32. Vimentin is the major intermediate filament
protein found in mesenchymal cells, which regulates cell In conclusion, we demonstrated that EMT and angio-
genesis play key roles in determining to what extent
sotetsuflavone can inhibit the invasion and metastasis of
NSCLC A549 cells. More importantly, we discovered that
sotetsuflavone could reverse EMT, thereby inhibiting the
migration and invasion of A549 cells. This process might
inhibit both PI3K/AKT and TNF-α/NF-κB signaling
pathways, and downregulate HIF-1α expression. There-
fore, HIF-1α may be a potential anticancer target for
sotetsuflavone. Figure
8
describes
this
proposed
mechanism. Official journal of the Cell Death Differentiation Association Page 6 of 11 Wang et al. Cell Death Discovery (2018) 4:26 Fig. 5 Sotetsuflavone inhibited MMP-9 and MMP-13 expressions. a Results from western blotting in detection of the expression of MMP-9 and
MMP-13 protein. Using the same sample lysates as used for Fig. 2a, another gel (gel D) was run, the blot was cut horizontally, and probed with anti-
MMP-9 and anti-MMP-13. The GAPDH loading control is from gel A, and is the same as shown in Fig. 2a. b Immunofluorescence assay detected the
expression of MMP-9. Scale bar 50 μm. c Immunofluorescence assay used to detect the expression of MMP-13. Scale bar 50 μm. The data in the
histogram represented the mean ± SD from three independent experiments (*P < 0.05, **P < 0.01, ***P < 0.001) Fig 5 Sotetsuflavone inhibited MMP 9 and MMP 13 expressions a Results from western blotting in detection of the expression of MMP 9 and Fig. 5 Sotetsuflavone inhibited MMP-9 and MMP-13 expressions. a Results from western blotting in detection of the expression of MMP-9 and
MMP-13 protein. Using the same sample lysates as used for Fig. 2a, another gel (gel D) was run, the blot was cut horizontally, and probed with anti-
MMP-9 and anti-MMP-13. Official journal of the Cell Death Differentiation Association Diagram of the proposed mechanism by which
sotetsuflavone inhibited NSCLC A549 cell invasion and
metastasis The GAPDH loading control is from gel A, and is the same as shown in Fig. 2a. b Immunofluorescence assay detected the
expression of MMP-9. Scale bar 50 μm. c Immunofluorescence assay used to detect the expression of MMP-13. Scale bar 50 μm. The data in the
histogram represented the mean ± SD from three independent experiments (*P < 0.05, **P < 0.01, ***P < 0.001) sotetsuflavone inhibited the expression of snail. At the
same time, sotetsuflavone significantly increased the
expression of the epithelial marker E-cadherin and
downregulated the expression of interstitial markers N-
cadherin and vimentin (Fig. 2a–c). This induced MET in
cells, reducing the ability of tumor cell invasion, and was
consistent with the reports of sulforaphane and other motility and proliferation, and its expression in epithelial
tumors is associated with cell invasiveness32. Studies have
demonstrated that sulforaphane, quercetin, and other
drugs can effectively inhibit EMT via inhibiting the
transcription of snail33. Therefore, this begs the question:
do anti-transfer effects of sotetsuflavone cause this? By
detecting EMT-related indicators, we demonstrated that Official journal of the Cell Death Differentiation Association Page 7 of 11 Wang et al. Cell Death Discovery (2018) 4:26 Fig. 6 Sotetsuflavone inhibited NF-κB pathway activation by downregulating TNF-α. a Results from western blotting on TNF-α and NF-κB
protein expression. Using the same sample lysates as used for Fig. 2a, another gel (gel E) was run and probed with anti-TNF-α and anti-NF-κB. The
GAPDH loading control is from gel A, and is the same as shown in Fig. 2a. b Expression of TNF-α and NF-κB mRNA as estimated by RT-PCR. The data
in the histogram represented the mean ± SD from three independent experiments (**P < 0.01, ***P < 0.001) Fig. 6 Sotetsuflavone inhibited NF-κB pathway activation by downregulating TNF-α. a Results from western blotting on TNF-α and NF-κB
protein expression. Using the same sample lysates as used for Fig. 2a, another gel (gel E) was run and probed with anti-TNF-α and anti-NF-κB. The
GAPDH loading control is from gel A, and is the same as shown in Fig. 2a. b Expression of TNF-α and NF-κB mRNA as estimated by RT-PCR. The data
in the histogram represented the mean ± SD from three independent experiments (**P < 0.01, ***P < 0.001) drugs. Therefore, these results suggest that sotetsuflavone
can inhibit the migration and invasion of A549 cells by
regulating EMT. formation
of
metastases36. Official journal of the Cell Death Differentiation Association Diagram of the proposed mechanism by which
sotetsuflavone inhibited NSCLC A549 cell invasion and
metastasis Therefore,
sotetsuflavone
should also inhibit tumor angiogenesis. As we predicted,
sotetsuflavone can significantly decrease the expression of
HIF-1α and VEGF in A549 cells and increase the
expression of angiostatin (Figs. 3a, b and 4a–c). HIF-1α is an oxygen-dependent transcription factor,
and a hypoxic environment promotes the high expression
of HIF-1α gene in tumor cells and plays an important role
in tumorigenesis, development, invasion, metastasis, and
apoptosis13. VEGF is the most powerful and specific
tumor angiogenesis-promoting factor currently known. When VEGF is combined with endothelial cells, it can
promote proliferation, migration, and growth of endo-
thelial cells34. VEGF is an important target gene of HIF-
1α. A high expression of HIF-1α upregulates the expres-
sion of VEGF, while upregulation of HIF-1α expression
can promote the formation of tumor angiogenesis. Additionally, it also plays a role in the growth, invasion,
and metastasis of NSCLC cancer tissues, suggesting that
blocking HIF-1α/VEGF pathway and inhibiting tumor
angiogenesis is an effective anticancer treatment plan35. Angiostatin is an isolated angiogenic inhibitor from tumor
cells and has a strong inhibitory effects on angiogenesis
that inhibit the proliferation and migration of tumor
vascular endothelial cells, prevent angiogenesis, promote
the primary animal tumor regression, and inhibit the EMT can promote the secretion of MMPs from tumor
cells, thereby degrading and destroying the ECM and
causing tumor cells to invade and migrate from the pri-
mary site37. Among them, MMP-9 is a kind of gelatinase
in MMPs capable of degrading IV-type collagen in the
ECM, which is involved in tumor invasion and metas-
tasis38,39. MMP-13 is in the central position of the MMPs’
activation cascade and participates in the degradation of
ECM. It also activates MMP-2 and MMP-9 to participate
in the development, progression, and invasion of several
tumors40. We discovered that both MMP-9 and MMP-13
expression
were
downregulated
by
sotetsuflavone
(Fig. 5a–c). Multiple signaling pathways are involved in the devel-
opment and progression of tumors in which the PI3K/
AKT pathway is an important factor for tumorigenesis41. Both PI3K/AKT and NF-κB pathways are involved in the
regulation of HIF-1α42. PI3K/AKT is frequently abnor-
mally activated in several human malignancies, and is Page 8 of 11 Wang et al. Cell Death Discovery (2018) 4:26 Fig. 7 Sotetsuflavone inhibited PI3K/AKT signaling pathway. a Results from western blotting showing expression of PI3K and AKT protein. Using
the same sample lysates as used for Fig. Diagram of the proposed mechanism by which
sotetsuflavone inhibited NSCLC A549 cell invasion and
metastasis 2a, another gel (gel F) was run, the blot was cut horizontally, and probed with anti-PI3K and anti-AKT. The
GAPDH loading control is from gel A, and is the same as shown in Fig. 2a. b Results from RT-PCR shows the expression of PI3K and AKT mRNA. The
data in the histogram represented the mean ± SD from three independent experiments (**P < 0.01, ***P < 0.001) Fig. 7 Sotetsuflavone inhibited PI3K/AKT signaling pathway. a Results from western blotting showing expression of PI3K and AKT protein. Using
the same sample lysates as used for Fig. 2a, another gel (gel F) was run, the blot was cut horizontally, and probed with anti-PI3K and anti-AKT. The
GAPDH loading control is from gel A, and is the same as shown in Fig. 2a. b Results from RT-PCR shows the expression of PI3K and AKT mRNA. The
data in the histogram represented the mean ± SD from three independent experiments (**P < 0.01, ***P < 0.001) closely related to tumor recurrence, metastasis, and drug
resistance, and has become a hot topic in tumor-targeting
drug research43. PI3K/AKT signaling pathway regulates
the expression of snail and induces the occurrence of
EMT44. We discovered that the expression of PI3K and
AKT were downregulated after sotetsuflavone-treated
A549 cells (Fig. 7a, b). In combination with previous
results (Fig. 3a, b), it was suggested that the inhibition of
HIF-1α expression by sotetsuflavone may be related to the
inhibition of PI3K and AKT expression. TNF-α is an
important inflammatory factor, and multiple lines of evi-
dence point to the critical role of TNF-α in tumor pro-
liferation, migration, invasion, and angiogenesis45. TNF-α
has been widely recognized as an important regulator of
the tumor microenvironment. The TNF-α/NF-κB path-
way plays an important role in tumor cell invasion and
metastasis45. We examined the effect of sotetsuflavone on
the TNF-α/NF-κB pathway. Our results indicated that
sotetsuflavone can downregulate TNF-α and inhibit the
activation of the NF-κB pathway (Fig. 6a, b). Sotetsu-
flavone can inhibit epithelial interstitial transformation,
invasion, and metastasis of lung cancer cells in A549 cells
through both PI3K/AKT and TNF-α/NF-κB pathways. In summary, sotetsuflavone can inhibit the invasion,
migration, and EMT of A549 lung cancer cells. Its
mechanism may be involved with the inhibition of PI3K/
AKT and TNF-α/NF-κB pathways (Fig. 8). Our results
provide a new theoretical basis for the application of
sotetsuflavone in molecular targeted therapy of lung
adenocarcinoma. Official journal of the Cell Death Differentiation Association Cell culture and drug preparation BCA protein concentration assay kit (AS1086), and
enhanced chemiluminescence detection kit (AS1059)
were
purchased
from
Aspen
biological
(Wuhan,
China). StepOne™
Real-Time
PCR
System
was
purchased from Life Technologies (Shanghai, China). Anti-angiostatin, GAPDH, VEGF, MMP-9, MMP-13,
TNF-α, and snail were purchased from Abcam (Shanghai,
China). NF-κB p65, AKT, PI3K, and E-cadherin were
purchased
at
Cell
Signaling
Technology
(Shanghai,
China). HIF-1α purchased from Santa Cruz Biotechnology
(Shanghai,
China). Secondary
antibody
horseradish
peroxidase (HRP)-goat anti-rabbit, HRP-goat anti-mouse,
fluorescein
isothiocyanate
(FITC)-goat
anti-rabbit,
FITC-goatanti-mouse, CY3-goat anti-rabbit, CY3-goat
anti-mouse, and CY3-donkey anti-goat were purchased
from
Aspen
Biological
(Wuhan,
China);
DR-200Bs
ELISA
was
purchased
from
Wuxi
Hiwell
Diatek
Instruments Co., Ltd. (Wuxi, China). MicroPublisher
imaging
system
(QImaging)
was
purchased
from
Shanghai Puch Biotechnology Co. Ltd. (Shanghai, China). CX-21 general optical microscope and IX51 inverted
microscope were purchased from Olympus Corporation
(Beijing, China). A549 cells were cultured in DMEM medium containing
10% fetal bovine serum, 100 U/ml penicillin, and 100 U/
ml streptomycin in 5% CO2 at 37℃. Logarithmic growth
phase cells were used. Sotetsuflavone solution was pre-
pared as a concentrate of 200 mM with dimethylsulfoxide,
stored at −20 °C, and diluted to the required concentra-
tion with DMEM medium before use. CDDP solution: N,
N-two methyl formamide was first used to prepare a
concentrate of 12 mg/ml, and then diluted with DMEM
medium to 10 g/ml for the experiment. Materials, reagents, and instruments Sotetsuflavone was isolated in our lab (purity: >98%,
high-performance liquid chromatography). CDDP (10
mg/bottle) was purchased from Qilu Pharmaceutical Co.,
Ltd. (Ji’nan, China). A549 cells (AS6011), phosphate-
buffered saline (PBS; AS1025), and 4′,6-diamidino-2-
phenylindole (DAPI) dye (AS1075) were purchased from
Wuhan Aspen Biotechnology Co., Ltd. (Wuhan, China). Dulbecco’s
modified
Eagle
medium
(DMEM)
high-
glucose
medium
(SH30022)
was
purchased
from
HyClone (Los Angeles, USA). Transwell board bought at
Corning
Incorporated
(Shanghai,
China). SDS-
polyacrylamide gel electrophoresis (SDS-PAGE) gel pre-
paration kit (AS1012), RIPA total protein lysate (AS1004), Official journal of the Cell Death Differentiation Association Page 9 of 11 Wang et al. Cell Death Discovery (2018) 4:26 Fig. 8 Diagram of the proposed mechanism by which sotetsuflavone inhibits non-small-cell lung cancer A549 cell invasion and metastasis. Sotetsuflavone inhibited the invasion and metastasis of A549 cells by inhibiting EMT and angiogenesis. The anti-transfer effect of sotetsuflavone was
mainly through downregulation of HIF-1α by the inhibition of PI3K/AKT and TNF-α/NF-κB signaling pathway in A549 cells, adjusting the whole
process Fig. 8 Diagram of the proposed mechanism by which sotetsuflavone inhibits non-small-cell lung cancer A549 cell invasion and metastasis. Sotetsuflavone inhibited the invasion and metastasis of A549 cells by inhibiting EMT and angiogenesis. The anti-transfer effect of sotetsuflavone was
mainly through downregulation of HIF-1α by the inhibition of PI3K/AKT and TNF-α/NF-κB signaling pathway in A549 cells, adjusting the whole
process Official journal of the Cell Death Differentiation Association Western blot analysis and scratch-healing rate (%) = (initial scratch width −
scratch width of specified time)/initial scratch width ×
100%. y
A549 cells were treated with 0, 64, 128 μmol/l sotetsu-
flavone for 24 h, and total protein was extracted with
RIPA lysis buffer. The protein samples were separated by
SDS-PAGE and then transferred to a polyvinylidene
fluoride membrane, and closed 1 h with TBST solution
containing 5% skim milk powder, we added the primary
antibodies overnight at 4℃. After three washes of 10 min
each in TBST, the membranes were incubated with HRP-
conjugated secondary antibodies for 1.5 h and subse-
quently washed again. An ECL detection system was used
to visualize immunoreactive bands. Equal protein sample
loading was monitored by probing the same membrane
with antibodies against GAPDH. Migration assay A549 cells in logarithmic growth phase were inoculated
into six-well plates at 1 × 106 cells/well. When the cells
had adhered to 90%, they were crossed vertically with a
20 μl pipette tip in the middle of each well. Plates were
then washed with PBS three times to remove the scraped
cells. After adding sotetsuflavone 0 (control group), 32,
64, and 128 μmol/L, the culture was allowed to grow in 5%
CO2 at 37 ℃. CDDP was used as a positive control drug. The scratch width changes of sotetsuflavone and CDDP
on A549 cells for 24 h were observed under a microscope, Official journal of the Cell Death Differentiation Association Page 10 of 11 Wang et al. Cell Death Discovery (2018) 4:26 Reverse transcription-PCR assay A549 cells were treated with different concentrations (0,
64, and 128 μmol/l) for 24 h, then total RNAs was
extracted using the Trizol cell lysis method. After mea-
suring the purity and concentration, then added reverse
transcription reagent, and transcribed at 37 °C for 15 min. The cDNA was reacted with the upstream and down-
stream primers and SYBR Green fluorescent dye was
added for real-time quantitative PCR. The following PCR
program was used: denaturation 95 °C for 1 min, followed
by 40 cycles consisting of denaturation at 95 °C for 15 s,
annealing at 58 °C for 20 s, and extension 72 °C for 45 s, A
melting curve analysis was applied to assess the specificity
of the amplified PCR products. The PCR primers were as
follows:
VEGF,
forward
5′-GAACTTTCTGCTGTCT
TGGGTG-3′ and reverse 5′-GGCAGTAGCTGCGCT-
GATAG-3′; TNF-α, forward 5′-CTCTTCTCCTTCCTG
ATCGTGG-3′ and reverse 5′-CTTGTCACTCGGGGTT
CGAG-3′; NF-κB,
forward 5′-CGCATCCAGACCAA-
CAACA-3′ and reverse 5′-TGCCAGAGTTTCGGTTC
AC-3′;
vimentin,
forward
5′-CAGGCAAAGCAG-
GAGTCCAC-3′ and reverse 5′-TATTCACGAAGGT-
GACGAGCC-3′; snail, forward 5′-GGCTGCTACAAGG
CCATGTC-3′ and reverse 5′-ACTCTTGGTGCTTGTG-
GAGCA-3′;
N-cadherin,
forward
5′-AGAGGCAGA-
GACTTGCGAAAC-3′
and
reverse
5′-ACACTGGCA
AACCTTCACGC-3′; PI3K, forward 5′-GTCCTATTG
TCGTGCATGTGG-3′ and reverse 5′-TGGGTTCTCCC
AATTCAACC-3′;
AKT,
forward
5′-
TTCTATGGC
GCTGAGATTGTGT-3′ and reverse 5′-GCCGTAGT-
CATTGTCCTCCAG-3′; and GAPDH, forward 5′-GG
TCGGAGTCAACGGATTTG-3′ and reverse 5′-GGAA-
GATGGTGATGGGATTTC-3′. The amount of each
target gene was quantified by the comparative CT method
using GAPDH as the normalization control. Immunofluorescent staining A549 cells were cultivated in 24-well plates and treated
by sotetsuflavone. Then the cells were washed with PBS
three times for 5 min and fixed with 4% paraformaldehyde
for 30 min. After permeabilization with 0.1% Triton
X-100, cells were blocked with 5% bovine serum albumin
for 1 h, and incubated with primary antibodies at 4 °C
overnight. After washing with PBS, the cells were incu-
bated with secondary antibodies corresponding to the
primary antibody for 50 min at 37 °C, and counterstained
with DAPI. Images were taken using a MicroPublisher
imaging system. Statistical analysis The
experimental
data
were
processed
by
SPSS
20.0 statistical software. All experiments were repeated at
least three times. The measurement data were expressed
as mean ± standard deviation (x ± s). The one-way ana-
lysis of variance was used to analyze the variance, when
the variance was homogeneous, with LSD, SNK test,
conversely, use Dunnett T3 test. P-values <0.05 were
considered statistically significant. Acknowledgements This study was supported by the Creative Item of Innovative Team of Ministry
of Education (No. IRT-13R63), National Training Programs of Innovation and
Entrepreneurship for Undergraduates (No. GCYS2016110001), and Training
Programs of Innovation and Entrepreneurship for Undergraduates of Minzu
University of China (No. MCYS2017110007). Conflict of interest The authors declare that they have no conflict of interest. Invasion assay We took 50 μl of Matrigel and the 1:3 of culture medium
dilution liquid and added it to the Transwell chamber. We
then collected 200 μl 105 cells/ml cell suspension (serum-
free medium) in a Transwell chamber, and added 500 μl/
well of 0, 32, 64, 128 μmol/l of sotetsuflavone and 10 μg/ml
of cisplatin, and incubated at 37 °C for 24 h. The medium
was removed and the A549 cells in the upper chamber
were wiped with cotton swabs. Cells were fixed in for-
maldehyde for 20 min, dried, and stained with the solution
of PBS 0.01% crystal violet for 10 min. Crystal violet was
washed from the surface, and five images were taken at
random under an inverted microscope, and the number of
transmembrane cells in the photographs were counted. Official journal of the Cell Death Differentiation Association References Cell. Mol. Life Sci. 68, 3033–3046 (2011). 9. Lee, J. M., Dedhar, S., Kalluri, R. & Thompson, E. W. The epithelial-mesenchymal
transition: new insights in signaling, development, and disease. J. Cell Biol. 172,
973–981 (2006). 33. Shankar, S. et al. Resveratrol inhibits pancreatic cancer stem cell characteristics
in human and KrasG12D transgenic mice by inhibiting pluripotency main-
taining factors and epithelial-mesenchymal transition. PLoS ONE 6, e16530
(2011). 10. Franco-Chuaire, M. L., Magda Carolina, S. C. & Chuaire-Noack, L. Epithelial-
mesenchymal transition (EMT): principles and clinical impact in cancer therapy. Invest. Clin. 54, 186–205 (2013). 34. Yu, D. M., Yan, X. C., Guo, D. Y., Liu, F. X. & Liu, L. M. Expressions of VEGF and
nm23 protein in transitional cell carcinoma of the bladder and their clinical
significance. Acta Acad. Med. Mil. Tertiae 28, 2180–2182 (2006). 11. Wang, Y. et al. CUL4A induces epithelial-mesenchymal transition and pro-
motes cancer metastasis by regulating ZEB1 expression. Cancer Res. 74,
520–531 (2014). 35. Kausar, H. et al. Berry anthocyanidins synergistically suppress growth and
invasive potential of human non-small-cell lung cancer cells. Cancer Lett. 325,
54–62 (2012). 12. Li, H. Q. & Ke, Y. Mechanism of epithelial-mesenchymal transition. Chin. Pharmacol. Bull. 31, 1342–1344 (2017). 36. Cao, Y. et al. Expression of angiostatin cDNA in a murine fibrosarcoma sup-
presses primary tumor growth and produces longterm dormancy of metas-
tases. J. Clin. Invest. 101, 1055–1063 (1998). 13. Semenza, G. L. Targeting HIF-1 for cancer therapy. Nat. Rev. Cancer 10,
721–732 (2003). 37. Yoo, Y. A. et al. Sonic hedgehog pathway promotes metastasis and lym-
phangiogenesis via activation of Akt, EMT, and MMP-9 pathway in gastric
cancer. Cancer Res. 71, 7061–7070 (2011). 14. Bergqvist, S., Ghosh, G. & Komives, E. A. The IkappaBalpha/NF-kappaB complex
has two hot spots, one at either end of the interface. Protein Sci. 17,
2051–2058 (2008). 15. Mak, P. et al. ERbeta impedes prostate cancer EMT by destabilizing HIF-1alpha
and inhibiting VEGF-mediated snail nuclear localization: implications for
Gleason grading. Cancer Cell 17, 319–332 (2010). 38. Qiao, Z. K., Li, Y. L., Lu, H. T., Wang, K. L. & Xu, W. H. Expression of tissue levels of
matrix metalloproteinases and tissue inhibitors of metalloproteinases in renal
cell carcinoma. World J. Surg. Oncol. 11, 1 (2013). 16. Li, W. et al. Decreased MT1-MMP in gastric cancer suppressed cell migration
and invasion via regulating MMPs and EMT. Tumor Biol. 36, 6883–6889 (2015). 39. References 1. Siegel, R., Naishadham, D. & Jemal, A. Cancer statistics. CA Cancer J. Clin. 64,
9–29 (2014). 2. Anderws, J., Yeh, P., Pao, W. & Horn, L. Molecular predictors of response to
chemotherapy in non-small cell lung cancer. Cancer J. 17, 104–113 (2011). 27. Song, I. S. et al. Regulation of glucose metabolism-related genes and VEGF by
HIF-1alpha and HIF-1beta, but not HIF-2alpha, in gastric cancer. Exp. Mol. Med. 41, 51–58 (2009). 3. Keith, R. L. & Miller, Y. E. Lung cancer chemoprevention: current status and
future prospects. Nat. Rev. Clin. Oncol. 10, 334–343 (2013). future prospects. Nat. Rev. Clin. Oncol. 10, 334–343 (2013). 4. Li, W. et al. Fei-Liu-Ping ointment inhibits lung cancer growth and invasion by
suppressing tumor inflammatory microenvironment. BMC Complement Altern. Med. 14, 153 (2014). 28. Lam, S. Y., Tipoe, G. L., Liong, E. C. & Fung, M. L. Differential expressions
and roles of hypoxia-inducible factor-1alpha, -2alpha and -3alpha in the rat
carotid body during chronic and intermittent hypoxia. Histol. Histopathol. 23,
271–280 (2008). 5. Berghmans, T., Paesmans, M. & Sculier, J. P. Prognostic factors in stage III non-
small cell lung cancer: a review of conventional, metabolic and new biological
variables. Ther. Adv. Med. Oncol. 3, 127–138 (2011). 29. Jiang, H., Zhu, Y. S., Xu, H., Sun, Y. & Li, Q. F. Inflammatory stimulation
and hypoxia cooperatively activate HIF-1α in bronchial epithelial cells: invol-
vement of PI3K and NF-κB. Am. J. Physiol. Lung Cell. Mol. Physiol. 298,
L660–L669 (2010). 6. Xu, L. et al. Multi-center randomized double-blind controlled clinical study of
chemotherapy combined with or without traditional Chinese medicine on
quality of life of postoperative non-small cell lung cancer patients. BMC
Complement Altern. Med. 12, 112 (2012). 30. Coulerie, P. et al. Structure-activity relationship study of biflavonoidson
the dengue virus polymerase DENV‑NS5 RdRp. Planta Med. 79, 1313–1318
(2013). 7. Moawad, A., Hetta, M., Zjawiony, J. K., Ferreira, D. & Hifnawy, M. Two new
dihydroamentoflavone glycosides from Cycas revolute. Nat. Prod. Res. 28,
41–47 (2014). 31. Pinho, S. S. et al. Loss and recovery of Mgat3 and GnT-III mediated E-cadherin
N-glycosylation is a mechanism involved in epithelial-mesenchymal-epithelial
transitions. PLoS ONE 7, e33191 (2012). 8. Moawad, A. et al. Phytochemical inves tigation of Cycas circinalis and Cycas
revolute leaflets: moderately active antibacterial biflavonoids. Planta Med. 76,
796–802 (2010). 32. Satelli, A. & Li, S. Vimentin in cancer and its potential as a molecular target for
cancer therapy. References Herszényi, L., Hritz, I., Lakatos, G., Varga, M. Z. & Tulassay, Z. The behavior of
matrix metalloproteinases and their inhibitors in colorectal cancer. Int. J. Mol. Sci. 13, 13240–13263 (2012). 17. Shah, P. P. & Kakar, S. S. Pituitary tumor transforming gene induces epithelial to
mesenchymal transition by regulation of Twist, Snail, Slug, and E-cadherin. Cancer Lett. 311, 66–76 (2011). y
g g
p
mesenchymal transition by regulation of Twist, Snail, Slug, and E-cadherin. Cancer Lett. 311, 66–76 (2011). 40. Wang, R., LI, X. Z., Zhang, Y. & Zhang, J. Expression and clinical significance of
MMP-13 in breast cancers by tissue microarray. Int. J. Pathol. Clin. Med. 29,
469–472 (2009). 18. Sethi, S., Macoska, J., Chen, W. & Sarkar, F. H. Molecular signature of epithelial-
mesenchymal transition(EMT)in human prostate cancer bone metastasis. Am. J. Transl. Res. 3, 90–99 (2010). 41. Bakin, A. V., Tomlinson, A. K., Bhowmick, N. A., Moses, H. L. & Arteaga, C. L. Phosphatidylinositol 3-kinase fuction is required for transforming growth
factor beta-mediated epithelial to mensenchymal transition and cell migra-
tion. J. Biol. Chem. 275, 36803–36810 (2000). 19. Gos, M., Miloszewska, J. & Przybyszewska, M. Epithelial-mesenchymal transition
in cancer progression. Postepy Biochem. 55, 121–128 (2009). 20. Hugo, H. J. et al. Defining the E-cadherin repressor interactome in epithelial-
mesenchymal transition: the PM C42 model as a case study. Cells Tissues
Organs 193, 23–40 (2011). 42. Jiang, H., Zhu, Y. S., Xu, H., Sun, Y. & Li, Q. F. Inflammatory stimulation
and hypoxia cooperatively activate HIF-1α in bronchial epithelial cells: invol-
vement of PI3K and NF-κB. Am. J. Physiol. Lung Cell. Mol. Physiol. 298, 660–669
(2010). 21. Nguyen, P. T. et al. N-cadherin expression is correlated with metastasis of
spindle cell carcinoma of head and neck region. J. Oral Pathol. Med. 40, 77–82
(2011). 43. Porta, C., Paglino, C. & Mosca, A. Targeting PI3K/Akt/mTOR signaling in cancer. Front. Oncol. 4, 64 (2014). 22. Wu, Y. & Zhou, B. P. TNF-alpha/NF-kapaB/Snail pathway in cancer cell
migration and invasion. Br. J. Cancer 102, 639–644 (2010). 44. Bachelder, R. E. & Mercurio, A. M. Glycogen synthase kinase-3 is an endo-
genous inhibitor of Snail transcription: implication for the epithelial to men-
senchymal transition. Cell Biol. 168, 29–33 (2005). 23. Melnikova, V. O. & Bar-Eli, M. Transcriptional control of the melanoma malig-
nant phenotype. Cancer Biol. Ther. 7, 997–1003 (2008). 23. Melnikova, V. O. & Bar-Eli, M. Transcriptional control of the 45. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations. Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations. Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations. Received: 27 October 2017 Revised: 17 December 2017 Accepted: 22
December 2017 Official journal of the Cell Death Differentiation Association Page 11 of 11 Wang et al. Cell Death Discovery (2018) 4:26 26. Xiang, Z. L. et al. Gene expression profiling of fixed tissues identified hypoxia-
inducible factor-1α, VEGF, and matrix metalloproteinase-2 as biomarkers of
lymph node metastasis in hepatocellular carcinoma. Clin. Cancer Res. 17,
5463–5472 (2011). References Wu, Y. & Zhou, B. P. TNF-a/NF-kB/Snail pathway in cancer cell migration and
invasion. Br. J. Cancer 102, 639–644 (2010). nant phenotype. Cancer Biol. Ther. 7, 997–1003 (2008). 24. Schuurbiers, O. C. et al. The PI3-K/Akt-pathway and radiation resistance
mechanisms in nonsmall cell lung cancer. J. Thorac. Oncol. 4, 761–767 (2009). 25. Semenza, G. L. Targeting HIF-1 for cancer therapy. Nat. Rev. Cancer 3, 721–732
(2003). Official journal of the Cell Death Differentiation Association
|
https://openalex.org/W4295046460
|
https://www.scielo.br/j/aabc/a/fVkZLqpP4BdjVFZnDt6ZCxb/?lang=en&format=pdf
|
English
| null |
Hederagenin Exerts Potential Antilipemic Effect via p38MAPK Pathway in Oleic Acid-induced HepG2 cells and in Hyperlipidemic Rats
|
Anais da Academia Brasileira de Ciências
| 2,022
|
cc-by
| 6,337
|
MENG YANG, JING WANG & QIAOLING WANG Abstract: Hederagenin, a natural compound distributed in many medicinal plants, has
a variety of pharmacological properties including anti-bacteria, anti-infl ammation, anti-
oxidation, and anti- apoptosis.. The aim of this study was to evaluate the effects of
hederagenin on decreasing blood lipid and anti-oxidative stress in oleic acid-induced
HepG2 cells and hyperlipidemic rats, and explore underlying mechanisms. In vitro, TG was
used as the index to verify the lipid-lowering effect of hederagenin in oleic acid-induced
HepG2 cells. In vivo, TC, TG, LDL-C, and HDL-C were used as direct indicators to study the
antilipemic effect of hederagenin in hyperlipidemic rats. MDA, SOD, and GSH-PX were
measured to analyze the anti-oxidative effect of hederagenin. The signaling pathways of
anti-oxidation were evaluated using Western blot. Our results showed that hederagenin
(250μmol/L) increased signifi cantly TG clearance rate. In addition, treatment with
hederagenin, XZK and simvastatin reduced effectively TC, TG, LDL-C and MDA content,
and increased HDL-C, SOD and GSH-PX in HFD rats. Moreover, the phosphorylation level
of p38 MAPK was inhibited after administration of hederagenin, XZK and simvastatin. Our results revealed that hederagenin possessed benefi cial potentials for hypolipidemic
effects, especially in TG clearance. The mechanism might be associated with inhibition
of lipid absorption, reduction of lipid oxidation, and down-regulation of p38MAPK
phosphorylation. Key words: Hyperlipidemia, Hederagenin, p38MAPK phosphorylation, lipid-lowering. An Acad Bras Cienc (2022) 94(4): e20201909 DOI 10.1590/0001-3765202220201909
Anais da Academia Brasileira de Ciências | Annals of the Brazilian Academy of Sciences
Printed ISSN 0001-3765 I Online ISSN 1678-2690
www.scielo.br/aabc | www.fb.com/aabcjournal An Acad Bras Cienc (2022) 94(4): e20201909 DOI 10.1590/0001-3765202220201909
Anais da Academia Brasileira de Ciências | Annals of the Brazilian Academy of Sciences
Printed ISSN 0001-3765 I Online ISSN 1678-2690
www.scielo.br/aabc | www.fb.com/aabcjournal Hederagenin Exerts Potential Antilipemic Effect
via p38MAPK Pathway in Oleic Acid-induced
HepG2 cells and in Hyperlipidemic Rats MENG YANG, JING WANG & QIAOLING WANG An Acad Bras Cienc (2022) 94(4) INTRODUCTION respectively. Abnormal lipid metabolism greatly
increased the occurrence of cardiovascular
and cerebrovascular diseases (coronary heart
disease, ischemic stroke, etc.) (Wu et al. 2006,
Sarwar et al. 2007). As scientifi c investigation
showed that about 4.4 million people died every
year from ischemic stroke and heart disease
induced by elevated cholesterol in serum
(Conroy et al. 2003, Guilbert 2003). H yperlipoidemia (H LP), a disorder of lipid
metabolism, refers to the pathological state
that the level of t otal cholesterol (TC) and/or
t riglyceride (TG) in serum or plasma increases
independently or simultaneously in fasting
condition (Liu et al. 2011). According to the results of the 2012 Chinese
lipid census, the morbidity of various types
of abnormal lipid metabolism was 11.43%
(Moran et al. 2010). Among patients with lipid
metabolism disorder, the average TC and TG
in adult serum were 4.50 mmol/L and 1.38
mmol/L, with prevalence rates of 4.9% and 13.1% Clinical treatment of high blood fat
disease was broadly divided into cholesterol-
lowering drugs (statins, cholic acid chelators
etc. (H et al. 2001)) and triglyceride-lowering
drugs (bate, niacin, etc.) (Rubins et al. 1999, An Acad Bras Cienc (2022) 94(4) An Acad Bras Cienc (2022) 94(4) ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG fat-diet (HFD) could lead to an increase of TC
and TG in serum (Fu et al. 2019). Therefore, in
this study, we investigated the lipid-lowering
effects of using oleic acid-induced HepG2 cells
and HFD-induced hyperlipidemia animal model. Furthermore, the p38MAPK signaling pathway
related to lipid metabolism and antioxidant was
evaluated and validated. Together, we provided
evidence that hederagenin could lower the level
of lipid, which might be associated with the
inhibition of p38MAPK signaling pathway. Keech et al. 2005, Das et al. 2010, Group et al. 2010). However, some hypolipidemic agents
could lower both cholesterol and triglycerides,
especially for severe hyperlipidemia. Although
statins are effective in lowering lipids, they have
serious side effects, such as liver damage and
rhabdomyolysis. Hederagenin, a pentacyclic triterpene are
widely distributed in many medicinal plants,
such as dipsacus asperoids, clematis chinensis,
radix pulsatillae, lonicerae japonicae, etc. Studies have found that hederagenin has a
variety of properties such as anti-tumor, anti-
depression, anti-bacteria and anti-inflammation
and anti-diabetes (Kim et al. 2017a, b). However,
a function of hederagenin in lowering blood
lipid or anti-hyperlipidemia is not clear. Animals and Treatment Male Sprague–Dawley (SD) rats (180–220 g) were
purchased from Comparative Medical Center
in Yangzhou University, Jiangsu Province, China
(Certificate No: SCXK2019-0117), and maintained
on a 12-hour light–dark cycle, 22 ± 1°C,55 ± 3%
humidity, with ad libitum feeding. All the animal
experiments were carried out according to the
Guidelines of Chinese Experimental Animal
Administration Legislation, and were approved
by the Animal Ethics Committee of China
(Document No: 55, 2019). HepG2 cells with good growth status were
cultured in Dulbecco’s modified Eagle’s medium
(DMEM) high sugar medium containing 1%
fetal bovine serum (FBS) and 2% Bovine serum
protein (BSA). Cells were grown in 37°C with a
humidified atmosphere containing 5% CO2. HepG2 cells was seeded in in 24-well plates
when the concentration was adjusted to about
105 / mL. After incubation for 24 h, HepG2 cells
were set as blank group, model group, XZK group,
Simvastatin group, and different concentration
hederagenin group, each with 3 parallel wells. The blank group was added to 1% FBS high
glucose DMEM medium containing 2% BSA, and
the model group was added 1% FBS high glucose
DMEM medium containing a final concentration
of 1 mmol/L oleic acid to each well. In the
XZK group, 1% FBS high-sugar DMEM medium
containing a final concentration of 1 mmol/L
oleic acid and 200 μg/mL drug was added to each
well. In the simvastatin group, 1% FBS high-sugar
DMEM medium containing a final concentration
of 1 mmol/L oleic acid and 20 μg/mL drug was
added to each well. The hederagenin group was
supplemented with 1% FBS high glucose DMEM
medium containing a final concentration of 1
mmol/L oleic acid and different concentrations
of drugs. Materials Hederagenin (Shanghai Chunyou biotechnology
co., LTD., p0207-201906); PBS powder (Sigma
company, Lot : P2198); Oleic acid (Sigma
company, Lot : 191P13759); Fetal bovine serum
(FBS) (Hyclone, Lot : 19156); Bovine serum
protein (BSA) (Jiangsu Kaiji biotechnology co.,
LTD., Lot : 20191121); DMSO (Nanjing chemical
reagent co., LTD., Lot : 20190908); Western and
IP cell lysates (Jiangsu Kaiji biotechnology co.,
LTD., Lot : 20191221); DMEM high sugar medium
(Gibco, USA, Lot : 1989124); HEPES (Jiangsu
Kaiji biotechnology co., LTD., Lot : 20191121);
Penicillin (Solarbio, Lot : 119A0322); Streptomycin
(Solarbio, Lot : 423A0520); Trypsin (Jiangsu Kaiji
biotechnology co., LTD., Lot : 20191121); BCA
protein kit (Nanjing Jiancheng biotechnology
co., LTD., Lot : 20191229); Total cholesterol (TC)
assay kit, total triglyceride (TG) assay kit, low
density lipoprotein cholesterol (LDL-C) assay
kit, high density lipoprotein cholesterol (HDL-C)
assay kit (Nanjing Jiancheng biotechnology co.,
LTD. Lot: 20191229); Malondialdehyde (MDA) test
kit, Total superoxide dismutase (SOD) assay
kit, Glutathione peroxidase (GSH-PX) assay kit
(Nanjing Jiancheng biotechnology co., LTD. Lot :
20191229). Hyperlipidemia is often accompanied by lipid
oxidation caused by oxygen free radicals (Omari-
Siaw et al. 2016). In the process of producing
oxidized lipids, malondialdehyde (MDA) is the
product of reaction of polyunsaturated fatty
acids and an active oxygen, whose changes in
concentration reflects the level of lipid oxidation
(Wang et al. 2015, Lykkesfeldt 2007). Superoxide
dismutase (SOD) is an antioxidant enzyme with
a level that reflects the ability of free radicals to
remove oxygen in the body (Wang et al. 2015). As
an important peroxidase decomposing enzyme,
glutathione-peroxidase (GSH-PX) can transform
the lipid peroxides into more stable hydroxyl
compounds in time and block the free radical
chain reaction in lipid peroxidation (Bednarek-
Tupikowska et al. 2001). It is well known that activated molecules
can indirectly trigger a variety of stress-
sensitive serine/threonine kinase signaling
pathways including the p38 isoform mitogen-
activated protein kinase (p38MAPK) (Klaunig et
al. 2010). The current research had shown that
hederagenin was documented to inhibit MAPK
activation (Tian et al. 2020). Moreover, a high An Acad Bras Cienc (2022) 94(4) e20201909 2 | 12 ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG Animals and Treatment Then place the 24-well plate in a
constant temperature incubator and incubate
for 24 hours, then remove the culture medium,
wash it twice with PBS, and then use Western
and IP cell lysate for ice bath for 30 min, collect
the lysate, and centrifuge at 4 12000 r/min for 10
minutes, take the supernatant, and determine
the triglyceride and protein content according to
the operating steps on the kit, each group has 6
parallel holes, and the results are expressed in
mmol/gprot, and the intracellular TG clearance
rate of each administration group is calculated
at the same time After adaptive feeding for a week, seventy SD
rats were randomly divided into 7 groups; there
were blank group, Model group, Simvastatin
group (2.1 mg/k/d), Xuezhikang group (XZK, 126
mg/kg/d), Hederagenin low-dose group (H-L, 9.0
mg/kg/d), Hederagenin middle-dose group (H-
M, 27.0 mg/kg/d), and Hederagenin high-dose
group (H-H, 81.0 mg/kg/d).The blank group was
fed normal diet; the other groups were fed HFD
(HFD, containing 8% soybean oil, 44% sweetened
condensed milk and 48% basic diet comprised of
15.5% protein, 33.4% fat and 51.1% carbohydrates.)
(Fki et al. 2005). After 6 weeks of feeding with
HFD, the rats were administered intragastrically
for next 8 weeks. The body weight of rats was
recorded daily. Blood Samples and Liver Tissue Preparation After the last intragastric administration, blood
samples were drawn from the abdominal aorta
when rats were anesthetized deeply with 20%
urethane, then the liver was excised from rats
and was stored in ice-cold normal saline. Determination of TC, TG, Low-Density
Lipoprotein-Cholesterol (LDL-C) and High-
Density Lipoprotein-Cholesterol (HDL-C) Data analysis Data are represented as means ±standard
deviation (
). Statistical analysis of
differences between groups was performed
by one-way ANOVA using SPSS 19 statistical
software. Differences were considered signifi cant
at P < 0.05. Effect of Hederag enin on TG in HepG2 Cells
Induced by Oleic Acid Compared with the blank group, the TG in
the model g roup increased significantly,
indicating that the oleic acid-induced HepG2
cell fat accumulation model was successfully
established. As shown in Table I, compared
with the model group, XZK, simvastatin,
and hederagenin (100 μmol/L, 250 μmol/L)
signifi cantly reduced the level of TG (P <0.01);
TG clearance rates were: 30.84%, 41.94%, 24.76%,
and 35.81%, respectively. Meanwhile, the result
showed that hederagenin administration led to
decreased TG in a dose-dependent manner. ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG the absorbance was measured with a microplate
reader. Determinatio n of SOD, MDA, and GSH-PX The liver ti ssue was homogenized by cold
normal saline (1 mg liver tissue in 9 ml of normal
saline). The supernatants were separated in
condition of 3,000 rpm, 20 min. The protein
concentrati ons were detected by Coomassie blue
protein binding using bovine serum album as a
standard. Test kits were used to detect the levels
of SOD, MDA and GSH-PX in supernatants, whose
procedures followed strictly the manufacturer’s
specifi cation (Wei et al. 1997, Katiyar et al. 2011). Determination of TC, TG, Low-Density
Lipoprotein-Cholesterol (LDL-C) and High-
Density Lipoprotein-Cholesterol (HDL-C) The serum obtained from blood samples was
operated according to the instructions of the
TC, TG, LDL-C and HDL-C kits respectively, and An Acad Bras Cienc (2022) 94(4) e20201909 3 | 12 Western blots The liver samples were lysed with cold lysis
buffer (Solarbio, Beijing, China), and the samples
homogenates were centrifuged at 13,000 rpm
for 15 min at 4 °C. The protein concentrations
of supernatant were determined with a BCA
protein assay kit (Beyotime, Jiangsu, China). The protein samples were mixed with loading
buffer in a volume ratio of 4:1 and then boiled
for 10 min. Subsequently, the protein samples
were separated on 5% SDS-PAGE and transferred
to a polyvinylidene fl uoride (PVDF) membrane . The PVDF membranes were blocked for 1.5 h in
5% skim milk and subjected to immunoblotting
using primary anti-MAPK antibody overnight
at 4 °C. Then, the PVDF membranes were
washed three time of 10 min each with TBST
and incubated with secondary horseradish
peroxidase (HRP)-conjugated antibody for 2 h at
room temperature. The blotting of membranes
was detected by chemiluminescence (ECL)
kits (Millipore, Billerica, MA, USA) and Bio-Rad
imaging systems. Relative intensities of protein
bands were analyzed by Image J software. Table I. Effect of hederagenin on TG content in HepG2
fat accumulation model(
SD
±
X
n=10). Group
Final
concentration
TG
content(mmol/
gprot)
TG
clearance
rates (%)
Blank group
--
0.531±0.041
--
Model group
--
2.27±0.127**
--
XZK
200 μg/mL
1.57±0.039##
30.84
Simvastatin
group
20 μg/mL
1.318±0.042##
41.94
Hederagenin
250 μmol/L
1.457±0.061##
35.81
100 μmol/L
1.708±0.056##
24.76
Signifi cant differences (**P<0.01 vs blank group; ##P<0.01
vs model group) were analyzed using one-way ANOVA. TG
clearance rate%=(TG model group-TG dose group )/TG model group ×100%. TG: Triglyceride; XZK:XueZhiKang. Table I. Effect of hederagenin on TG content in HepG2
fat accumulation model(
SD
±
X
n=10). Effect of Hederagenin on Body Weight improved, especially in the hederagenin high-
dose group (H-H) after drug administration for 8
weeks. The levels of TC, TG, and LDL-C in the H-H
group were 24.2%, 27.3% and 23.1% lower than
those in the model group, respectively (P<0.05),
and the HDL-C level in the H-H group was 6.4%
higher than that in the model group (Fig. 1a-
d). The simvastatin treatment also significantly
improved the serum TC, TG, LDL-C and HDL-C
levels compared to the model group (P < 0.05). All animals survived in the duration of the
treatment. The result showed that HFD-induced
model group, simvastatin group, XZK group, H-L
group, H-M group, and H-H group were heavier
than blank group before administration (P<0.01)
(table II). However, compared with the model
group, simvastatin group, XZK group, H-L group,
H-M group, and H-H group markedly improve
the body weight induced by HFD at end of drug
administration (P<0.01) (table II). The body weight
of each group increased respectively before
administration and the last administration:
32.8% in the blank group, 55.1% in the model
group, 38.5% in the simvastatin group, 47.7% in
the XZK group, 49.9% in the H-L group, and 39.8%
in the H-M group and 37.5% in the H-H group. Table I. Effect of hederagenin on TG content in HepG2
fat accumulation model(
SD
±
X
n=10). An Acad Bras Cienc (2022) 94(4)
e20201909 4 | 12 ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG Effect of Hederagenin on Response to
Oxidative Stress Furthermore, this study investigated whether
hederagenin decreased the level of lipid in HFD-
induced rats is associated with the effect of that
on anti-oxidation. As shown as Fig. 2a, Compared
with the blank group, it can be observed that the
liver MDA level of the model group is 2.03 fold
that of the blank group, which indicates that HFD
significantly induced the increase of the liver
MDA level (P < 0.01). XZK, Simvastatin H-L, H-M
and H-H treatment could markedly reverse the
HFD-induced increase of liver MDA level (36.2%,
44.5%, 24.6%, 31.8% and 36.9%(respectively)
versus model group rats (P < 0.01, P < 0.05). Moreover, the levels of liver SOD and GSH-PX An Acad Bras Cienc (2022) 94(4) e20201909 5 | 12 Effect of Hederagenin on the Level of Lipid Next, we tested whether the decrease of weight
in HFD-induced models is related to hederagenin
effect on the level of lipid. The levels of TC, TG and
LDL-C were increased remarkably in the model
group compared with the blank group, and the
level of HDL-C decreased significantly, indicating
that hyperlipidemia model was established
successfully. The serum lipid profile markedly Table II. Effect on body weight of rats fed a basic diet or a HFD from 6 weeks to 14 weeks(
SD
±
X
n=10). Section
Time
Blank
group
Model
Simvastatin
XZK
H-L
H-M
H-H
Before
administration
6 weeks
325.6±6.4
352.3±9.6**
349.4±10.3**
353±9.5**
351.6±10.7**
353.2±11.7**
355.2±10.5**
Begin
administration
7 weeks
336.95±7.6
377±13.7**
369.8±13.4 #
376.8±12.3
375.6±14.5
376.6±13.3
374.2±12.9
8 weeks
351.45±9.2
399.6±15.1**
388.6±16.5
399.5±14.4
399±15.3
397.3±16.4
393.7±15.1
9 weeks
366.05±8.4
426.5±14.6**
406.2±15.9#
422.3±13.8
424.7±17.6
416.4±14.9
411.1±16.0#
10 weeks
380.95±8.3
450.1±17.3**
423.1±19.2##
443.6±15.3
447.3±19.4
433.7±15.6#
431.8±18.2#
11 weeks
394.2±10.5
474.3±20.5**
438.8±18.4##
464.8±17.8
468.8±19.8
449.6±17.2##
446.9±17.6##
12 weeks
406.8±10.7
499.8±21.7**
454.1±20.7##
485.2±20.4#
489.3±21.3
464.4±19.7##
460.9±20.3##
13 weeks
419.7±12.1
523.9±22.8**
469.8±19.3##
503.7±22.8#
508.9±24.2#
479.2±20.9##
475.1±22.8##
14 weeks
432.3±14.5
546.4±25.3**
483.9±22.8##
521.4±24.1##
527.2±25.6##
493.8±22.1##
488.3±21.9##
**P<0.01 vs blank group; #P<0.05, ##P<0.01vs model group were analyzed using one-way ANOVA. HFD: high Fat-Diet; XZK:XueZhiKang;
H-L: Hederagenin low dose group; H-M: Hederagenin medium dose group; H-H:Hederagenin high-dose group. ody weight of rats fed a basic diet or a HFD from 6 weeks to 14 weeks(
SD
±
X
n=10). Table II. Effect on body weight of rats fed a basic diet or a HFD from 6 weeks to 14 weeks( X **P<0.01 vs blank group; #P<0.05, ##P<0.01vs model group were analyzed using one-way ANOVA. HFD: high Fat-Diet; XZK:XueZhiKang;
H-L: Hederagenin low dose group; H-M: Hederagenin medium dose group; H-H:Hederagenin high-dose group. An Acad Bras Cienc (2022) 94(4) e20201909 5 | 12 ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG (P<0.05) compared with model group. These
results indicated that hederagenin treatment
could improve the response to oxidative stress
in rats induced by HFD. in the model group rats were lower than blank
group rats(42.3% and 48.0%)respectively (Fig. 2b-c, P < 0.01). However, XZK, simvastatin, H-L,
H-M, and H-H groups increased dramatically the
activity of SOD (36.7%, 48.4%, 25.1%, 31.2% and
38.0%(respectively) (P < 0.01) and GSH-PX (46.4%,
65.9%, 31.2%, 40.4% and 55.2%(respectively) ,
,
(
p
y)
Figure 1. Effects of hederagenin on the level of lipid (n = 8). Effect of Hederagenin on the p38MAPK
Pathway Effect of Hederagenin on the p38MAPK Effect of Hederagenin on the Level of Lipid A: Effects of hederagenin on TC in serum. B: Effects
of hederagenin on TG in serum. C: Effects of hederagenin on LDL-C in serum. D: Effects of hederagenin on HDL-C
in serum. H-L: Low-dose of hederagenin H-M: Middle-dose of hederagenin; H-H: High- dose of hederagenin. The
values are shown as the means ± sd, n=10 for each group. Significant differences ( **P<0.01 vs blank group; #P<0.05,
##P<0.01 vs model group) were analyzed using one-way ANOVA. TC: Total cholesterol; TG: Triglyceride; LDL-C: Low
density lipoprotein cholesterol; HDL-C: High density lipoprotein cholesterol; XZK: XueZhiKang; H-L: Hederagenin
low dose group; H-M: Hederagenin medium dose group; H-H: Hederagenin high-dose group. Figure 1. Effects of hederagenin on the level of lipid (n = 8). A: Effects of hederagenin on TC in serum. B: Effects
of hederagenin on TG in serum. C: Effects of hederagenin on LDL-C in serum. D: Effects of hederagenin on HDL-C
in serum. H-L: Low-dose of hederagenin H-M: Middle-dose of hederagenin; H-H: High- dose of hederagenin. The
values are shown as the means ± sd, n=10 for each group. Significant differences ( **P<0.01 vs blank group; #P<0.05,
##P<0.01 vs model group) were analyzed using one-way ANOVA. TC: Total cholesterol; TG: Triglyceride; LDL-C: Low
density lipoprotein cholesterol; HDL-C: High density lipoprotein cholesterol; XZK: XueZhiKang; H-L: Hederagenin
low dose group; H-M: Hederagenin medium dose group; H-H: Hederagenin high-dose group. An Acad Bras Cienc (2022) 94(4) e20201909 6 | 12 ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG Effect of Hederagenin on the p38MAPK
Pathway
DISCUSSION
Figure 2. Effects of hederagenin
on response to oxidative
stress in liver (n = 8). a: Effect
of hederagenin on SOD in
serum. b: Effect of hederagenin
on MDA in serum. c: Effects
of hederagenin on GSH-PX
in serum. H-L: Low-dose
hederagenin H-M: Middle-dose
hederagenin; H-H: High-dose
hederagenin. Significant
differences (**P<0.01vs blank
group; #P<0.05, ##P<0.01vs
model group) were analyzed
using one-way ANOVA. MDA:
Malondialdehyde; SOD: Total
superoxide dismutase; GSH-PX:
Glutathione peroxidase; XZK:
XueZhiKang; H-L: Hederagenin
low dose group; H-M:
Hederagenin medium dose
group; H-H: Hederagenin high-
dose group. Effect of Hederagenin on the p38MAPK
Pathway
DISC
H Figure 2. Effects of hederagenin
on response to oxidative
stress in liver (n = 8). a: Effect
of hederagenin on SOD in
serum. b: Effect of hederagenin
on MDA in serum. c: Effects
of hederagenin on GSH-PX
in serum. Effect of Hederagenin on the Level of Lipid H-L: Low-dose
hederagenin H-M: Middle-dose
hederagenin; H-H: High-dose
hederagenin. Significant
differences (**P<0.01vs blank
group; #P<0.05, ##P<0.01vs
model group) were analyzed
using one-way ANOVA. MDA:
Malondialdehyde; SOD: Total
superoxide dismutase; GSH-PX:
Glutathione peroxidase; XZK:
XueZhiKang; H-L: Hederagenin
low dose group; H-M:
Hederagenin medium dose
group; H-H: Hederagenin high-
dose group. Figure 2. Effects of hederagenin
on response to oxidative
stress in liver (n = 8). a: Effect
of hederagenin on SOD in
serum. b: Effect of hederagenin
on MDA in serum. c: Effects
of hederagenin on GSH-PX
in serum. H-L: Low-dose
hederagenin H-M: Middle-dose
hederagenin; H-H: High-dose
hederagenin. Significant
differences (**P<0.01vs blank
group; #P<0.05, ##P<0.01vs
model group) were analyzed
using one-way ANOVA. MDA:
Malondialdehyde; SOD: Total
superoxide dismutase; GSH-PX:
Glutathione peroxidase; XZK:
XueZhiKang; H-L: Hederagenin
low dose group; H-M:
Hederagenin medium dose
group; H-H: Hederagenin high-
dose group. Effect of Hederagenin on the p38MAPK
Pathway DISCUSSION Hyperlipidemia with TC, TG, LDL-C and HDL-C
as main reference indicators is a leading
cause of death from cardiovascular diseases
throughout the globe (Le 2008). It is well known
that hyperlipidemia is key risk factor of heart
diseases, including atherosclerosis and coronary
heart disease (Rosenson 2006, Le & Walter 2007,
Das et al. 2010). Statins are the mainstay of lipid-
lowering therapy in clinic which primarily act
on LDL, also slightly lower the level of TG, and
induce a moderate increase in HDL-C. However,
statins have additional risk factors of increasing
side effects and adverse drug interactions. In
the meantime, previous studies had shown
that hederagenin could effectively treat tumors
through anti-oxidation (Kim et al. 2017a) and anti-
inflammation (Lee et al. 2015). Lowering blood
lipids is often closely related to properties of anti-
oxidation (Stein et al. 2020, Gimeno-Mallench How hederagenin improved the response to
oxidative stress in rats induced by HFD is not
clear. Therefore, the proteins related to p38MAPK
pathway were tested with Western blot. Fig. 3
displayed the effects of hederagenin on the levels
of total- p38 and p-p38. There was no striking
difference in total-p38 expression between blank
group and other groups. However, HFD induced
p38MAPK phosphorylation, leading to p38MAPK
signaling activation. Compared to the blank
group, phosphorylation of p38MAPK in the model
group significantly overexpressed. In treatment
groups (simvastatin, XZK, H-L, H-M, and H-H),
however, the expression of phosphorylation of
p38MAPK significantly decreased. Interestingly,
the hederagenin treatment groups were
observed in dose-dependent manner in
decrease of phosphorylation of p38MAPK. An Acad Bras Cienc (2022) 94(4) e20201909 7 | 12 ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG Figure 3. Effects of hederagenin treatment on the
p38MAPK pathway in the rats (n = 3). **P<0.01vs blank
group; ##P<0.01 vs model group were analyzed using
one-way ANOVA. p38MAPK: p38 isoform mitogen-
activated protein kinase; p-p38: Phosphorylated
p38 mitogen-activating protease; XZK: XueZhiKang;
H-L: Hederagenin low dose group; H-M: Hederagenin
medium dose group; H-H: Hederagenin high-dose
group. protect HepG2 cells from oleic acid by reducing
intracellular TG level. This study adopted a HFD to establish
an animal model of hyperlipidemia similar to
human disease, with highly reproducible results
and easy operation. DISCUSSION Previous studies had shown
that rats who were fed a high cholesterol diet for
6 weeks showed a significant increase levels of
TC and LDL-C in serum (Fki et al. 2005), which was
consistent with the results of our study. Our study
demonstrates that hederagenin could effectively
slow the trend of weight gain in rats fed a HFD. In
addition, this study also showed that hederagenin
had a dose-dependent effect, the reasons for
this were unclear, and we suspected that it might
be related to the suppression of lipid absorption. Our data demonstrated hederagenin
notably improved lipid profile, thereby exerting
hypolipidemic effect. Among them, hederagenin
was effective in reducing TG which is a key risk
factor of atherosclerosis, heart disease and fatty
liver. If there is overabundance of TG, hoarding
in the subcutaneous would lead to body obesity;
hoarding in the blood vessel wall would cause
atherosclerosis; hoarding in the heart would lead
to heart hypertrophy; and hoarding in the liver
would cause fatty liver. These were the leading
causes of mortality throughout the globe (Le
2008). As we know, liver is one of the main organs
of TG synthesis and metabolism. Liver cells are
involved in many stages of lipid metabolism;
therefore, it is possible that hyperlipidemia
drives the development of fatty liver (Lee et al. 2014, Tessari et al. 2009). It is reported that most
cholesterol is synthesized by the body itself, and
a little is obtained from the diet (Kapourchali et
al. 2016). On the contrary, TG are mostly obtained
from the diet and a small part is made by the body
itself (Alves-Bezerra & Cohen 2017). Therefore, the
best way to reduce TG is to inhibit TG absorption. Our results show that Hederagenin has a good TG
clearance rate and is dose-dependent, which may Figure 3. Effects of hederagenin treatment on the
p38MAPK pathway in the rats (n = 3). **P<0.01vs blank
group; ##P<0.01 vs model group were analyzed using
one-way ANOVA. p38MAPK: p38 isoform mitogen-
activated protein kinase; p-p38: Phosphorylated
p38 mitogen-activating protease; XZK: XueZhiKang;
H-L: Hederagenin low dose group; H-M: Hederagenin
medium dose group; H-H: Hederagenin high-dose
group. et al. 2019) and anti-inflammation (Canesi et
al. 2019). However, there are no studies have
reported that hederagenin can decrease
blood lipid. Therefore, we hypothesized that
hederagenin had the effect of reducing blood
lipids and conducted a preliminary study on its
mechanism. ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG DISCUSSION In vitro studies, preliminary results
showed that hederagenin (100 mol/L, 250 mol/L)
had beneficial effect on oleic acid induced-
HepG2 cells. This proved that hederagenin could An Acad Bras Cienc (2022) 94(4) e20201909 8 | 12 REFERENCES KATIYAR D, SINGH B, LALL AM & HALDAR C. 2011. Efficacy of
chitooligosaccharides for the management of diabetes
in alloxan induced mice: a correlative study with
antihyperlipidemic and antioxidative activity. Eur J Pharm
Sci 44: 534-543. ALVES-BEZERRA M & COHEN DE. 2017. Triglyceride Metabolism
in the Liver. Compr Physiol 8: 1-8. ALVES-BEZERRA M & COHEN DE. 2017. Triglyceride Metabolism
in the Liver. Compr Physiol 8: 1-8. BEDNAREK-TUPIKOWSKA G, BOHDANOWICZ-PAWLAK A, BIDZINSKA
B, MILEWICZ A, ANTONOWICZ-JUCHNIEWICZ J & ANDRZEJAK
R. 2001. Serum lipid peroxide levels and erythrocyte
glutathione peroxidase and superoxide dismutase activity
in premenopausal and postmenopausal women. Gynecol
Endocrinol 15: 298-303. KEECH A ET AL. 2005. Effects of long-term fenofibrate
therapy on cardiovascular events in 9795 people with
type 2 diabetes mellitus (the FIELD study): randomised
controlled trial. Lancet 366: 1849-1861. KEECH A ET AL. 2005. Effects of long-term fenofibrate
therapy on cardiovascular events in 9795 people with
type 2 diabetes mellitus (the FIELD study): randomised
controlled trial. Lancet 366: 1849-1861. CANESI F, MATEO V, COUCHIE D, KARABINA S, NEGRE-SALVAYRE
A, ROUIS M & EL HADRI K. 2019. A thioredoxin-mimetic
peptide exerts potent anti-inflammatory, antioxidant,
and atheroprotective effects in ApoE2.Ki mice fed high fat
diet. Cardiovasc Res 115: 292-301. KIM EH, BAEK S, SHIN D, LEE J & ROH JL. 2017a. Hederagenin
Induces Apoptosis in Cisplatin-Resistant Head and Neck
Cancer Cells by Inhibiting the Nrf2-ARE Antioxidant
Pathway. Oxid Med Cell Longev 2017: 5498908. KIM EH, BAEK S, SHIN D, LEE J & ROH JL. 2017a. Hederagenin
Induces Apoptosis in Cisplatin-Resistant Head and Neck
Cancer Cells by Inhibiting the Nrf2-ARE Antioxidant
Pathway. Oxid Med Cell Longev 2017: 5498908. KIM GJ, SONG DH, YOO HS, CHUNG KH, LEE KJ & AN JH. 2017b. Hederagenin Supplementation Alleviates the Pro-
Inflammatory and Apoptotic Response to Alcohol in Rats. Nutrients 9. CONROY RM ET AL. 2003. Estimation of ten-year risk of fatal
cardiovascular disease in Europe: the SCORE project. Eur
Heart J 24: 987-1003. DAS PP, MALHOTRA S, CHAKRABARTI S & SHARMA S. 2010. Elevated total cholesterol in severely depressed patients:
role in cardiovascular risk? World J Biol Psychiatry 11:
321-328. KLAUNIG JE, KAMENDULIS LM & HOCEVAR BA. 2010. Oxidative
stress and oxidative damage in carcinogenesis. Toxicol
Pathol 38: 96-109. LE NA. 2008. Hyperlipidemia and cardiovascular disease:
cardiovascular update. Curr Opin Lipidol 19: 545-547. FKI I, BOUAZIZ M, SAHNOUN Z & SAYADI S. 2005. ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG H KH, H S, P M, KNOPP R, CHIN B, GAZIANO JM, DONOVAN JM, BURKE
SK & DAVIDSON MH. 2001. Efficacy and safety of combination
simvastatin and colesevelam in patients with primary
hypercholesterolemia. Am J Med 24: 987-1003. H KH, H S, P M, KNOPP R, CHIN B, GAZIANO JM, DONOVAN JM, BURKE
SK & DAVIDSON MH. 2001. Efficacy and safety of combination
simvastatin and colesevelam in patients with primary
hypercholesterolemia. Am J Med 24: 987-1003. Acknowledgments This research was supported by Natural Science
Research Projects of Jiangsu Colleges and Universities
(17KJB350004). The assistance of the staff is gratefully
acknowledged. KAPOURCHALI FR, SURENDIRAN G, GOULET A & MOGHADASIAN
MH. 2016. The Role of Dietary Cholesterol in Lipoprotein
Metabolism and Related Metabolic Abnormalities: A Mini-
review. Crit Rev Food Sci Nutr 56: 2408-2415. CONCLUSION be the reason why hederagenin has an effective
anti-lipid effect. In conclusion, the present study identified the
scientific basis for the therapeutic effects of
hederagenin in the treatment of hyperlipidemia. Our results found that hederagenin possessed
the anti-oxidative potential for lipids-lowering
in the rats received HFD, which might be related
to suppression of p38MAPK phosphorylation. Hederagenin could inhibit MAPK pathway
activation, thus exert anti-oxidation and lipids-
lowering effect in rats induced by HFD. Oxidative stress is the unifying mechanism
for causing many cardiovascular diseases,
especially in atherogenesis (Singh & Jialal 2006,
Marchio et al. 2019, Peluso et al. 2012). In addition,
we learned that the main characteristics of anti-
oxidation was to reduce TG, increase HDL and
adiponectin, and prevent LDL from being oxidized. Therefore, we selected SOD, MDA, and GSH-PX as
anti-oxidative indicators to verify the antioxidant
capacity of hederagenin. The results showed HFD
induced oxidative stress reaction in rats, which
were consistent with previous studies (Meng et al. 2011). Our results also showed that the blood lipid
levels and anti-oxidative index of hederagenin
showed a precise correlation (Fig. 1 and Fig. 2). Therefore, we believed that anti-oxidative stress
may be one of the lipid-lowering mechanisms
of hederagenin, which was consistent with other
studies (Wang et al. 2020, Pengrattanachot et
al. 2020) on lipid lowering and anti-oxidation
results. Thus, hederagenin might be used as an
antioxidant to treat hyperlipidemia. Abbreviations
BSA
Bovine serum protein
DMEM
DMEM dulbecco’s modified eagle medium
FBS
Fetal bovine serum
GSH-PX
Glutathione peroxidase
HDL-C
High density lipoprotein cholesterol
HFD
high fat-diet
H-H
Hederagenin high-dose group
H-L
Hederagenin low dose group
HLP
Hyperlipoidemia
H-M
Hederagenin medium dose group
LDL-C
Low density lipoprotein cholesterol
MDA
Malondialdehyde
p38MAPK
p38 isoform mitogen-activated protein
kinase
PVDF
polyvinylidene fluoride
SD
Sprague–Dawley
SOD
Total superoxide dismutase
TC
Total cholesterol
TG
Triglyceride
XZK
Xuezhikang Oxidative stress is well known to stimulate
the MAPK pathway activation, especially the
phosphorylation of p38MAPK. Furthermore,
in order to further confirm hederagenin anti-
oxidation activity, we conducted experiments
from a molecular perspective and offered
a plausible explanation for the molecular
mechanism of hederagenin on decreasing blood
lipid. The results of this study showed that HFD
promoted phosphorylation of p38MAPK. The
affections of oxidative stress on cellular signaling
pathways and activation of p38MAPK pathways
were inhibited by treatment with hederagenin,
simvastatin and XZK. An Acad Bras Cienc (2022) 94(4) e20201909 9 | 12 ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG TESSARI P, CORACINA A, COSMA A & TIENGO A. 2009. Hepatic
lipid metabolism and non-alcoholic fatty liver disease. Nutr Metab Cardiovasc Dis 19: 291-302. Focus on Oxidative Stress and Inflammation. Oxid Med
Cell Longev 2019: 8563845. Focus on Oxidative Stress and Inflammation. Oxid Med
Cell Longev 2019: 8563845. MENG R, ZHU DL, BI Y, YANG DH & WANG YP. 2011. Anti-oxidative
effect of apocynin on insulin resistance in high-fat diet
mice. Ann Clin Lab Sci 41: 236-243. TIAN K ET AL. 2020. Hederagenin protects mice against
ovariectomy-induced bone loss by inhibiting RANKL-
induced osteoclastogenesis and bone resorption. Life Sci
244: 117336. MORAN A ET AL. 2010. Future cardiovascular disease in
china: markov model and risk factor scenario projections
from the coronary heart disease policy model-china. Circ
Cardiovasc Qual Outcomes 3: 243-252. WANG L, TAO L, HAO L, STANLEY TH, HUANG KH, LAMBERT JD &
KRIS-ETHERTON PM. 2020. A Moderate-Fat Diet with One
Avocado per Day Increases Plasma Antioxidants and
Decreases the Oxidation of Small, Dense LDL in Adults
with Overweight and Obesity: A Randomized Controlled
Trial. J Nutr 150: 276-284. OMARI-SIAW E, WANG Q, SUN C, GU Z, ZHU Y, CAO X, FIREMPONG
CK, AGYARE R, XU X & YU J. 2016. Tissue distribution and
enhanced in vivo anti-hyperlipidemic-antioxidant effects
of perillaldehyde-loaded liposomal nanoformulation
against Poloxamer 407-induced hyperlipidemia. Int J
Pharm 513: 68-77. WANG M-M, MEI Z, ZHANG M, FAN Y, WANG P, DU Y-H & WANG
Y-FZL. 2015. Effects of pueraria extract on blood lipid and
antioxidant activity in hyperlipidemia rats. Science and
Technology of Food Industry 36: 369-372. PELUSO I, MORABITO G, URBAN L, IOANNONE F & SERAFINI M. 2012. Oxidative stress in atherosclerosis development:
the central role of LDL and oxidative burst. Endocr Metab
Immune Disord Drug Targets 12: 351-360. WEI YJ, LI KA & TONG SY. 1997. A linear regression method for
the study of the Coomassie brilliant blue protein assay. Talanta 44: 923-930. PENGRATTANACHOT N, CHERNGWELLING R, JAIKUMKAO K,
PONGCHAIDECHA A, THONGNAK L, SWE MT, CHATSUDTHIPONG
V & LUNGKAPHIN A. 2020. Atorvastatin attenuates obese-
induced kidney injury and impaired renal organic anion
transporter 3 function through inhibition of oxidative
stress and inflammation. Biochim Biophys Acta Mol Basis
Dis 1866: 165741. WU Y ET AL. 2006. Estimation of 10-year risk of fatal and
nonfatal ischemic cardiovascular diseases in Chinese
adults. Circulation 114: 2217-2225. How to cite YANG M, WANG J & WANG Q. 2022. Hederagenin Exerts Potential
Antilipemic Effect via p38MAPK Pathway in Oleic Acid-induced HepG2
cells and in Hyperlipidemic Rats. An Acad Bras Cienc 94: e20201909. DOI
10.1590/0001-3765202220201909. ROSENSON RS. 2006. Low high-density lipoprotein
cholesterol and cardiovascular disease: risk reduction
with statin therapy. Am Heart J 151: 556-563. RUBINS HB ET AL. 1999. Gemfibrozil for the secondary
prevention of coronary heart disease in men with low
levels of high-density lipoprotein cholesterol. Veterans
Affairs High-Density Lipoprotein Cholesterol Intervention
Trial Study Group. N Engl J Med 341: 410-418. Manuscript received on December 14, 2020;
accepted for publication on March 3, 2021 REFERENCES Hypocholesterolemic effects of phenolic-rich extracts of
Chemlali olive cultivar in rats fed a cholesterol-rich diet. Bioorg Med Chem 13: 5362-5370. LE NA & WALTER MF. 2007. The role of hypertriglyceridemia
in atherosclerosis. Curr Atheroscler Rep 9: 110-115. FU X, QIN T, YU J, JIAO J, MA Z, FU Q, DENG X & MA S. 2019. Formononetin Ameliorates Cognitive Disorder via PGC-
1alpha Pathway in Neuroinflammation Conditions in
High-Fat Diet-Induced Mice. CNS Neurol Disord Drug
Targets 18: 566-577. LEE CW ET AL. 2015. Hederagenin, a major component
of Clematis mandshurica Ruprecht root, attenuates
inflammatory responses in RAW 264.7 cells and in mice. Int Immunopharmacol 29: 528-537. LEE HS ET AL. 2014. Beneficial effects of phosphatidylcholine
on high-fat diet-induced obesity, hyperlipidemia and
fatty liver in mice. Life Sci 118: 7-14. GIMENO-MALLENCH L, MAS-BARGUES C, INGLES M, OLASO G,
BORRAS C, GAMBINI J & VINA J. 2019. Resveratrol shifts energy
metabolism to increase lipid oxidation in healthy old
mice. Biomed Pharmacother 118: 109130. LIU ZL, LIU JP, ZHANG AL, WU Q, RUAN Y, LEWITH G & VISCONTE D. 2011. Chinese herbal medicines for hypercholesterolemia. The Cochrane database of systematic reviews: CD008305. GROUP AS ET AL. 2010. Effects of combination lipid therapy
in type 2 diabetes mellitus. N Engl J Med 362: 1563-1574. LYKKESFELDT J. 2007. Malondialdehyde as biomarker of
oxidative damage to lipids caused by smoking. Clin Chim
Acta 380: 50-58. GUILBERT JJ. 2003. The world health report 2002 - reducing
risks, promoting healthy life. Educ Health (Abingdon) 16:
230. MARCHIO P, GUERRA-OJEDA S, VILA JM, ALDASORO M, VICTOR VM
& MAURICIO MD. 2019. Targeting Early Atherosclerosis: A MARCHIO P, GUERRA-OJEDA S, VILA JM, ALDASORO M, VICTOR VM
& MAURICIO MD. 2019. Targeting Early Atherosclerosis: A An Acad Bras Cienc (2022) 94(4) e20201909 10 | 12 ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro JING WANG JING WANG
https://orcid.org/0000-0002-0426-0585 MENG YANG https://orcid.org/0000-0003-0857-2815 SARWAR N, DANESH J, EIRIKSDOTTIR G, SIGURDSSON G, WAREHAM
N, BINGHAM S, BOEKHOLDT SM, KHAW KT & GUDNASON V. 2007. Triglycerides and the risk of coronary heart disease: 10,158
incident cases among 262,525 participants in 29 Western
prospective studies. Circulation 115: 450-458. QIAOLING WANG
https://orcid.org/0000-0003-4290-2187 SINGH U & JIALAL I. 2006. Oxidative stress and atherosclerosis. Pathophysiology 13: 129-142. School of Pharmaceutical Engineering, Jiang Su
Food & pharmaceutical science college, China, 4,
Meicheng Road, Huaian 223003, PR China STEIN E, SILVA IM, DORNELES GP, LIRA FS, ROMAO P & PERES A. 2020. Reduced Fat Oxidation During Exercise in Post-
Menopausal Overweight-Obese Women with Higher Lipid
Accumulation Product Index. Exp Clin Endocrinol Diabetes
128: 556-562. Correspondence to: Meng Yang
E-mail: yangmeng202006@163.com, 443282626@qq.com An Acad Bras Cienc (2022) 94(4) e20201909 11 | 12 ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro ANTILIPEMIC EFFECT OF HEDERAGENIN in vivo AND in vitro MENG YANG, JING WANG & QIAOLING WANG An Acad Bras Cienc (2022) 94(4) e20201909 12 | 12 Author contributions Research conception and design: MY and JW. Experiments and
analyzed the data: QLW and JW. Writing of the manuscript: MY. Revised the manuscript: QLW. All authors read and approved
the manuscript. An Acad Bras Cienc (2022) 94(4) e20201909 12 | 12
|
https://openalex.org/W4327611848
|
https://www.frontiersin.org/articles/10.3389/fphar.2023.1132689/pdf
|
English
| null |
Alcohol consumption modulates prelimbic cortex response to cocaine following sequential cocaine and alcohol polysubstance use in the rat
|
Frontiers in pharmacology
| 2,023
|
cc-by
| 7,560
|
OPEN ACCESS OPEN ACCESS
EDITED BY
George Panagis,
University of Crete, Greece
REVIEWED BY
Sheketha R. Hauser,
Indiana University Bloomington,
United States
Mary M. Torregrossa,
University of Pittsburgh, United States
Karen K. Szumlinski,
University of California, Santa Barbara,
United States
*CORRESPONDENCE
Lori A. Knackstedt,
knack@ufl.edu
SPECIALTY SECTION
This article was submitted to
Neuropharmacology,
a section of the journal
Frontiers in Pharmacology
RECEIVED 27 December 2022
ACCEPTED 07 March 2023
PUBLISHED 16 March 2023
CITATION
Mesa JR, Carter E, Padovan-Hernandez Y
and Knackstedt LA (2023), Alcohol
consumption modulates prelimbic cortex
response to cocaine following sequential
cocaine and alcohol polysubstance use in
the rat. Front. Pharmacol. 14:1132689. doi: 10.3389/fphar.2023.1132689 REVIEWED BY
Sheketha R. Hauser,
Indiana University Bloomington,
United States
Mary M. Torregrossa,
University of Pittsburgh, United States
Karen K. Szumlinski,
University of California, Santa Barbara,
United States Javier R. Mesa1,2, Emily Carter3, Yasmin Padovan-Hernandez 4 and
Lori A. Knackstedt1,2* 1Department of Psychology, University of Florida, Gainesville, FL, United States, 2Center for Addiction
Research and Education, University of Florida, Gainesville, FL, United States, 3Department of Psychology,
Pennsylvania State University, University Park, PA, United States, 4Solomon H. Snyder Department of
Neuroscience, Johns Hopkins University, Baltimore, MD, United States Polysubstance use (PSU), involves the consumption of more than one drug within
a period of time and is prevalent among cocaine users. Ceftriaxone, a beta-lactam
antibiotic, reliably attenuates reinstatement of cocaine seeking in pre-clinical
models
by
restoring
glutamate
homeostasis
following
cocaine
self-
administration but fails to do so when rats consume both cocaine and alcohol
(cocaine + alcohol PSU). We previously found that cocaine + alcohol PSU rats
reinstate cocaine seeking similarly to cocaine-only rats, but demonstrate
differences in reinstatement-induced c-Fos expression throughout the reward
system, including a lack of change upon ceftriaxone treatment. Here, we used this
model to determine if previous findings were caused by tolerance or sensitization
to the pharmacological effects of cocaine. Male rats underwent intravenous
cocaine self-administration immediately followed by 6 h of home cage access
to water or unsweetened alcohol for 12 days. Rats subsequently underwent
10 daily instrumental extinction sessions, during which time they were treated
with either vehicle or ceftriaxone. Rats then received a non-contingent cocaine
injection and were perfused for later immunohistochemical analysis of c-Fos
expression in the reward neurocircuitry. c-Fos expression in the prelimbic cortex
correlated with total alcohol intake in PSU rats. OPEN ACCESS There were no effects of either
ceftriaxone or PSU on c-Fos expression in the infralimbic cortex, nucleus
accumbens core and shell, basolateral amygdala, or ventral tegmental area. These results support the idea that PSU and ceftriaxone alter the neurobiology
underlying drug-seeking behavior in the absence of pharmacological tolerance or
sensitization to cocaine. CITATION
Mesa JR, Carter E, Padovan-Hernandez Y
and Knackstedt LA (2023), Alcohol
consumption modulates prelimbic cortex
response to cocaine following sequential
cocaine and alcohol polysubstance use in
the rat. Front. Pharmacol. 14:1132689. doi: 10.3389/fphar.2023.1132689 Front. Pharmacol. 14:1132689. doi: 10.3389/fphar.2023.1132689 COPYRIGHT
© 2023 Mesa, Carter, Padovan-
Hernandez and Knackstedt. This is an
open-access article distributed under the
terms of the Creative Commons
Attribution License (CC BY). The use,
distribution or reproduction in other
forums is permitted, provided the original
author(s) and the copyright owner(s) are
credited and that the original publication
in this journal is cited, in accordance with
accepted academic practice. No use,
distribution or reproduction is permitted
which does not comply with these terms. TYPE Brief Research Report
PUBLISHED 16 March 2023
DOI 10.3389/fphar.2023.1132689 TYPE Brief Research Report
PUBLISHED 16 March 2023
DOI 10.3389/fphar.2023.1132689 TYPE Brief Research Report
PUBLISHED 16 March 2023
DOI 10.3389/fphar.2023.1132689 frontiersin.org ethanol, polydrug, sensitization, neurocircuitry, relapse Introduction Cocaine use disorder (CUD) is a chronic, progressive condition marked by a strong
tendency for relapse even after prolonged periods of abstinence. In 2020, approximately
1.3 million Americans met DSM-5 criteria for CUD (SAMHSA, 2022) and there are
currently no FDA-approved medications to prevent cocaine relapse. It is possible that Frontiers in Pharmacology 01 frontiersin.org 10.3389/fphar.2023.1132689 Mesa et al. reinstatement tests (Sari et al., 2009; Knackstedt et al., 2010;
Trantham-Davidson
et
al.,
2012;
LaCrosse
et
al.,
2016). Furthermore, ceftriaxone attenuates cue-primed reinstatement of
alcohol seeking (Weiland et al., 2015), and decreases alcohol intake
in male Sprague-Dawley rats (Stennett et al., 2017). However,
following
alcohol
consumption,
ceftriaxone
upregulates
xCT
(Stennett et al., 2017), but not GLT1 (Pati et al., 2016),
expression in the NA core. reinstatement tests (Sari et al., 2009; Knackstedt et al., 2010;
Trantham-Davidson
et
al.,
2012;
LaCrosse
et
al.,
2016). Furthermore, ceftriaxone attenuates cue-primed reinstatement of
alcohol seeking (Weiland et al., 2015), and decreases alcohol intake
in male Sprague-Dawley rats (Stennett et al., 2017). However,
following
alcohol
consumption,
ceftriaxone
upregulates
xCT
(Stennett et al., 2017), but not GLT1 (Pati et al., 2016),
expression in the NA core. polysubstance use (PSU), the use of multiple drugs in a given time,
confounds efforts to find effective therapies against cocaine relapse. Of persons with CUD, a substantial portion consume alcohol
concurrently, sequentially, or simultaneously with cocaine (Kedia
et al., 2007; Liu et al., 2018; Liu et al., 2019). Alcohol dependence may
reduce the efficacy of CUD-treating medications in humans. For
instance, alcohol co-use prevents modafinil from reducing cocaine
seeking (Anderson et al., 2009). Thus, cocaine-alcohol PSU may
promote
unique
neuroadaptations
not
seen
in
cocaine
monosubstance use that undermine efforts to treat CUD. Despite the prevalence of cocaine + alcohol PSU, most pre-
clinical models of cocaine and alcohol use are monosubstance in
design and PSU models are lacking. Using a rodent model of
sequential cocaine + alcohol self-administration, we demonstrated
that sequential cocaine + alcohol PSU (alcohol immediately
following cocaine) induces unique neuroadaptations compared to
either monosubstance cocaine or alcohol use. Specifically, in male
Sprague-Dawley rats, cocaine + alcohol PSU results in increased NA
core GLT-1 expression while cocaine monosubstance use decreases
GLT-1 expression and alcohol has no effect (Stennett et al., 2020). Introduction The glutamate efflux that characterizes the reinstatement of cocaine
seeking is no longer present during cocaine-primed and cue +
cocaine-primed reinstatement in the PSU condition, despite
equivalent degrees of reinstated cocaine-seeking (Stennett et al.,
2020; Stennett and Knackstedt, 2020). Moreover, cue + cocaine-
primed reinstatement-induced c-Fos expression differs between
cocaine monosubstance and cocaine + alcohol PSU conditions. Namely,
in
the
basolateral
amygdala
(BLA),
greater
c-Fos
expression was observed in the cocaine + alcohol PSU condition
compared to the cocaine-only condition. Within the NA core and
shell and the PL and infralimbic (IL) cortices, cocaine-only rats
displayed greater c-Fos expression than did PSU rats. In these
regions,
ceftriaxone
reduced
c-Fos
expression
only
in
the
monosubstance condition and not in PSU. Within the ventral
tegmental area (VTA), ceftriaxone increased c-Fos expression in
monosubstance rats only and PSU rats demonstrated similar c-Fos
levels to vehicle-treated cocaine-only rats. Preclinical models of monosubstance use have identified
important changes in glutamate dynamics that underlie both
cocaine and alcohol seeking separately. Chronic cocaine self-
administration
dysregulates
glutamate
homeostasis
in
the
nucleus accumbens (NA) core, which underlies relapse to
cocaine seeking (McFarland et al., 2003; Kalivas, 2004). Two to
3 weeks of cocaine self-administration reduces local levels of basal
glutamate
(Trantham-Davidson
et
al.,
2012). Yet,
during
reinstatement of cocaine seeking, regardless of reinstatement
prime (cue, drug, footshock, context), NA core glutamate
transmission increases and impeding this increase attenuates
seeking behavior (McFarland et al., 2003; McFarland et al.,
2004; LaCrosse et al., 2016; Smith et al., 2017). More precisely,
this glutamate efflux arises from medial prefrontal cortical
afferents, primarily from the prelimbic cortex (PL) (McFarland
et al., 2003). Concordantly, chemogenetic and optogenetic
inhibition of the PL to NA core pathway during cocaine- and
cue-primed reinstatement consistently attenuates cocaine seeking
(Stefanik et al., 2013; Kerstetter et al., 2016; Stefanik et al., 2016;
Wright et al., 2018; Siemsen et al., 2022). Beyond changes in
neurotransmission, chronic cocaine self-administration reduces
NA
core
expression
of
the
glutamate
transporter GLT-1
(Knackstedt et al., 2010) and xCT (the catalytic subunit of the
cysteine glutamate antiporter system xc-) (Baker et al., 2003;
Knackstedt et al., 2010; Trantham-Davidson et al., 2012), both of
which are critical for maintaining glutamate homeostasis within
NA core. Various rodent models indicate less robust effects of
alcohol consumption on NA core glutamate homeostasis but
suggest that alcohol itself also dysregulates local glutamate
dynamics. Frontiers in Pharmacology Introduction Following weeks of chronic intermittent alcohol
vapor
exposure,
mice
exhibit
higher
levels
of
nucleus
accumbens
extracellular
glutamate
(Griffin
et
al.,
2014). Furthermore, several weeks of intermittent access to alcohol
increases basal glutamate levels in NA core (Griffin et al.,
2014) without altering GLT-1 (Pati et al., 2016) or xCT
expression in outbred Sprague Dawley rats (Stennett et al.,
2017). Some of these findings are more pronounced in alcohol
preferring C57BL/6J mice, which exhibit increased glutamate
efflux
in
NA
core
following
repeated
alcohol
injections
(Kapasova and Szumlinski, 2008). At
this
time,
it remains
unclear
whether
tolerance
or
sensitization to the pharmacological effects of cocaine following a
history of sequential cocaine + alcohol PSU underly the differences
seen following a cue + cocaine-primed reinstatement test. For
example, decreased c-Fos expression in the PSU condition in the
IL and PL could arise from decreased cocaine-induced glutamate
and/or dopamine release in these regions. We hypothesize that this
is not the case, and that the PSU- and ceftriaxone-induced
differences in c-Fos expression observed in our previous work
were due to differences in the circuitry engaged during relapse
and not tolerance or sensitization to the pharmacological effects of
cocaine. Here, we test this hypothesis by assessing pharmacological
tolerance
or
sensitization
to
non-contingent
cocaine
via
quantification of c-Fos expression in the PL, IL, NA core, NA
shell, BLA, and VTA of ceftriaxone and vehicle-treated rats that
self-administered cocaine-only or cocaine followed sequentially by
alcohol access in the homecage, exactly as in our previous work. C-fos is an immediate early gene that is produced upon stimulation
of dopamine and glutamate receptors (Morelli et al., 1992; Wang,
1998). Rats in the present study were not permitted the opportunity
to reinstate cocaine-seeking, thus allowing the assessment of the
isolated effects of the cocaine-priming injection on c-Fos expression
in the selected brain regions. Because NA core glutamate dysregulation underlies both
cocaine and alcohol seeking, one potential treatment for both
cocaine and alcohol use disorders is the beta-lactam antibiotic
ceftriaxone. In
rodents,
ceftriaxone
upregulates
NA
core
expression of GLT1 and xCT and restores local glutamate
reuptake following cocaine self-administration (Knackstedt et al.,
2010; Trantham-Davidson et al., 2012), while decreasing cocaine
seeking
behaviors
in
cocaine-,
cue-
and
context-primed 02 frontiersin.org Mesa et al. 10.3389/fphar.2023.1132689 URE 1
uential cocaine self-administration and subsequent two-bottle choice sessions. Immunohistochemistry Immediately following the 110-min re-exposure, rats were
euthanized and transcardially perfused using 4% PFA. Brains
were extracted and preserved in 4% PFA for 24 h before
transferring to 25% sucrose for 48 h. Brains were flash frozen
using isopentane and stored at −80°C. Using a cryostat, tissue
containing the PL, IL, NA core, NA shell, BLA, and VTA was
coronally sliced at 30 µM and stored in phosphate-buffered saline
with 0.01% sodium azide. Animals 8-week-old male Sprague Dawley rats (n = 41; Charles
River Laboratories LLC, Raleigh, NC) were housed in a
temperature-controlled vivarium and maintained on a 12 h
reverse-light cycle. Only male rats were used to permit
comparisons with our previous work on this topic, which also
used male rats. All procedures and testing were carried out
during the dark phase of the cycle. Animals were restricted to
20 g of standard rat chow daily and water was always provided ad
libitum. All procedures were approved by the University of
Florida’s Institutional Animal Care and Use Committee and
followed the Guidelines of the Care and Use of Laboratory
Animals. Surgeries Rats underwent jugular catheterization surgeries following the
intermittent access to alcohol period (described below). They were
anesthetized using ketamine (87.5 mg/kg, IP) and xylazine (5 mg/kg,
IP) administered at a volume of 1 mL/kg. One end of the catheter
(SILASTIC tubing, ID 0.51 mm, OD 0.94 mm, Dow Corning,
Midland, MI) was implanted into the jugular vein. The other end
exited through a midscapular incision and attached to a cannula
(Plastics One, Roanoake, VA) embedded in a harness (Instech,
Plymouth Meeting, PA), which allowed for intravenous (IV) drug
delivery. Drugs Thereafter, rats underwent extinction training, wherein active
lever presses did not yield cocaine infusions or corresponding cues. Rats did not receive access to either cocaine or alcohol during the
extinction period. During the final 5–7 days of extinction, 21 rats
(n = 11 PSU; n = 10 cocaine-only) were treated with ceftriaxone
(200 mg/kg, IP) while 19 rats (n = 11 PSU; n = 8 cocaine-only)
received vehicle. Cocaine
HCl
was
donated
by
the
NIDA
controlled
substances
program
(Research
Triangle
Institute,
NC)
and dissolved in 0.9% physiological saline as a 4 mg/mL
solution. Alcohol
(Fisher
Scientific,
100%)
was
diluted
to 20% v/v with tap water. Ceftriaxone (Sigma-Aldrich, St. Louis,
MO)
was
dissolved
in
0.9%
physiological
saline
vehicle and administered intraperitoneally (IP) at 200 mg/kg
in 1 mL/kg. To assess the pharmacological effects of non-contingent cocaine
on neuronal activation, rats were re-exposed to their respective
operant chambers for 110 min following an acute cocaine injection
(10 mg/kg, IP). During this period, neither lever was extended and
cocaine-associated cues were not presented. This time frame was
selected to maximize c-Fos expression induced by the cocaine
injection and follow our previous methods (Müller et al., 1984;
Young et al., 1991; Mahler and Aston-Jones, 2012; Stennett et al.,
2020). Materials and methods followed by a 20-s timeout period wherein additional active
presses
were
recorded
but
did
not
yield
programmed
consequences. Inactive lever presses did not deliver cues or
cocaine. Immediately
following
each
cocaine
self-
administration session, the same rats that had previously
received
intermittent
access
to
alcohol
(n
=
22)
were
presented
with
a
two-bottle
choice
between
water
and
unsweetened alcohol (20% v/v) in the home cage for 6 h,
while the remaining rats (n = 19) received access to only
water. Rats continued to self-administer cocaine and receive
only water or the two-bottle choice until they administered at
least 7 cocaine infusions per day for 12 days. One rat was
excluded for failure to meet self-administration criteria and
another for failed catheter patency. followed by a 20-s timeout period wherein additional active
presses
were
recorded
but
did
not
yield
programmed
consequences. Inactive lever presses did not deliver cues or
cocaine. Immediately
following
each
cocaine
self-
administration session, the same rats that had previously
received
intermittent
access
to
alcohol
(n
=
22)
were
presented
with
a
two-bottle
choice
between
water
and
unsweetened alcohol (20% v/v) in the home cage for 6 h,
while the remaining rats (n = 19) received access to only
water. Rats continued to self-administer cocaine and receive
only water or the two-bottle choice until they administered at
least 7 cocaine infusions per day for 12 days. One rat was
excluded for failure to meet self-administration criteria and
another for failed catheter patency. Frontiers in Pharmacology Introduction Access to alcohol does not alter intravenous cocaine self-
ministration variables, and rats later assigned to receive ceftriaxone and vehicle did not differ in cocaine or alcohol intake. (A) Timeline of methods. re were no differences in (B) active lever presses and (C) inactive lever presses across groups. (D) Cocaine intake did not vary between groups. Neither
alcohol intake during the IAA and cocaine self-administration periods nor (F) total alcohol intake differed in cocaine + alcohol PSU rats that
eived vehicle or ceftriaxone during extinction training. FIGURE 1
Sequential cocaine self-administration and subsequent two-bottle choice sessions. Access to alcohol does not alter intravenous cocaine self-
administration variables, and rats later assigned to receive ceftriaxone and vehicle did not differ in cocaine or alcohol intake. (A) Timeline of methods. There were no differences in (B) active lever presses and (C) inactive lever presses across groups. (D) Cocaine intake did not vary between groups. Neither
(E) alcohol intake during the IAA and cocaine self-administration periods nor (F) total alcohol intake differed in cocaine + alcohol PSU rats that
received vehicle or ceftriaxone during extinction training. 03 Frontiers in Pharmacology frontiersin.org 10.3389/fphar.2023.1132689 10.3389/fphar.2023.1132689 Mesa et al. Statistical analysis including for active lever presses (Figure 1B), inactive lever
presses (Figure 1C), and cocaine intake (Figure 1D). In cases
when Mauchly’s test of sphericity revealed a violation of the
equal variances assumption, all epsilon (ε) values were below
0.75 and Greenhouse-Geisser corrections were used to reduce
type I error. A main effect of Time on cocaine infusions was
found [F(5.872,211.386) = 8.459, p < 0.001], as infusions increased
over time for all groups. Similarly, a main effect of Time on cocaine
intake was found [F(5.53,199.091) = 8.263, p < 0.001]. While there was
no 3-way interaction for cocaine intake, there was a main effect of
Liquid on cocaine intake [F(1,36) = 6.271, p > 0.05]. To investigate
this further, we summed the total cocaine intake (mg/kg) across all
self-administration days and found no effects of Treatment or
Liquid on cocaine intake (not shown). Of note, a mechanical
failure on the first day of self-administration prevented recording
of inactive lever presses for some rats (n = 10) that day. Rats that
later received Vehicle and Ceftriaxone did not differ in the total
amount of alcohol consumed throughout the experiment [t{19.98) =
1.702, p > 0.05; Figure 1E]. We also found no Time x Treatment
interaction and no main effect of Treatment on alcohol intake across
the entire experiment (Figure 1F). When considering only the
12 days of cocaine-self-administration, we found that rats that
later received Ceftriaxone during extinction had reduced alcohol
intake [main effect of Treatment: F (1,15) = 4.547, p = 0.499]. SPSS Statistics 28 was used to conduct 3-way ANOVAs and
GraphPad Prism (9.4.1) was used to conduct 2-way ANOVAs,
mixed effects, and correlational analyses. All analyses used an
alpha level of 0.05. Mixed 3-way ANOVAs using Liquid (water
or alcohol), and Treatment (vehicle or ceftriaxone) as between-
subjects factors and Time as a within-subjects factor were used to
compare active lever presses, inactive lever presses, infusions, and
cocaine intake (mg/kg) across groups during the 12 days that self-
administration criteria were met and to examine lever presses during
extinction. Such analyses were used to balance ceftriaxone/vehicle
treatment within cocaine and cocaine + alcohol groups. An unpaired
t-test with Welch’s correction was also used to compare total alcohol
intake (mg/kg) in cocaine + alcohol rats between treatment groups. Intermittent access to alcohol and cocaine
self-administration To allow comparison between the present results and
our previous study, we largely replicated the methods used
in Stennett et al. (2020), with minor changes. Prior to
the cocaine self-administration period, rats that were later
in
the
cocaine
+
alcohol
PSU
condition
were
given intermittent access (IAA) to unsweetened alcohol for
five
24-h
sessions
on
alternating
days
(Figure
1A). All
rats were then trained to self-administer intravenous cocaine
for 2 h daily in a two-lever operant chamber. Active lever
presses yielded a 0.1 mL cocaine infusion over 2.5 s and 5-s
presentation
of
cues
(2900 Hz
tone
and
stimulus
light) To visualize c-Fos expression, free-floating slices were blocked in
2% normal donkey serum and then incubated overnight in rabbit
anti c-Fos antibody (1:10,000, EMD Millipore). Slices were then
incubated in biotinylated donkey anti-rabbit secondary antibody
followed by avidin-biotin complex (1:500, Vector Laboratories) and
3,3-diaminobenzidine
(Vector
Laboratories). Sections
were
mounted onto slides and coverslipped. Images were obtained at
20x using an AmScope MU1803 CMOS camera mounted to an
Olympus
BX51
microscope. Cellular
c-Fos
expression
was
quantified using NIH ImageJ software with a cell counter plug-in
(DeVos, 2001). 04 frontiersin.org Mesa et al. 10.3389/fphar.2023.1132689 FIGURE 2
There were no group differences in lever presses during instrumental extinction. Both (A) active and (B) inactive lever presses decreased during
extinction training, with no effects of liquid consumed or ceftriaxone/vehicle. FIGURE 2
There were no group differences in lever presses during instrumental extinction. Both (A) active and (B) inactive lever presses decreased during
extinction training, with no effects of liquid consumed or ceftriaxone/vehicle. Statistical analysis c-Fos expression per mm2 was calculated and averaged between
slices from the same region and rat and compared with 2-way Liquid
x Treatment ANOVAs. Total cocaine intake was also compared with
a 2-way ANOVA. Based on our a priori hypothesis that cocaine-
alcohol PSU leads to increased tolerance to cocaine, we also
conducted unpaired t-tests to compare c-Fos expression between
cocaine-only and PSU rats that received vehicle. Outlier data was
excluded when cell counts exceeded ≥2 standard deviations from
sample means. c-Fos expression between groups was compared
using 2-way ANOVAs with Liquid and Treatment as between-
subjects factors. Spearman’s rank correlation was used to assess
the strength of the relationship between total alcohol intake and total
cocaine intake with c-Fos expression in regions of interest in cocaine
+ alcohol PSU rats. During extinction training, there were no Liquid x Treatment x
Time interactions for presses on the previously active (Figure 2A) or
inactive (Figure 2B) levers. Active and inactive lever presses
decreased across all groups, evidenced by a main effect of Time
on active lever presses [F(1.98,71.285) = 43.624, p < 0.001] and inactive
lever presses [F(1.846,66.469) = 4.271, p > 0.05]. Frontiers in Pharmacology frontiersin.org Cocaine self-administration, drug intake,
and extinction Seven rats were excluded from c-Fos analysis due to poor
perfusions. The regions of interest were determined using a rat
brain atlas (Paxinos and Watson, 2007), and representative
diagrams of those regions are depicted in Figures 3A–C. Sample For cocaine self-administration variables, 3-way ANOVAs
found no significant Liquid x Treatment x Time interactions, 05 frontiersin.org Mesa et al. 10.3389/fphar.2023.1132689 FIGURE 3
Representative images of c-Fos expression from regions of interest. (A–C) Location of analysis with corresponding coordinates relative to Bregma. Representative images of c-Fos expression in regions of interest: (D) prelimbic cortex (PL); (E) nucleus accumbens (NA) shell; (F) basolateral amygdala
(BLA); and (G) ventral tegmental area (VTA). Green arrows represent c-fos + cells; scale bars = 100 µm. FIGURE 3
Representative images of c-Fos expression from regions of interest. (A–C) Location of analysis with corresponding coordinates relative to Bregma. Representative images of c-Fos expression in regions of interest: (D) prelimbic cortex (PL); (E) nucleus accumbens (NA) shell; (F) basolateral amygdala
(BLA); and (G) ventral tegmental area (VTA). Green arrows represent c-fos + cells; scale bars = 100 µm. images depicting c-Fos expression within the PL, NA shell, BLA and
VTA are shown in Figures 3D–G. differences in c-Fos expression for any brain region (Figures
4B–G). However, there were trends for reduced c-Fos expression
in the VTA [t(10) = 1.944, p = 0.08; Figure 4E] and NAs [t(13) = 2.093,
p = 0.057; Figure 4G] of the cocaine + alcohol group. There were no significant Treatment x Liquid interactions on
c-Fos expression for any brain region examined. A positive
correlation was found between total alcohol intake and PL c-Fos
expression in cocaine + alcohol rats (r = 0.6413, p > 0.01; Figure 4A). No other significant correlations were detected between c-Fos
expression and either cocaine or alcohol intake. To test the
hypothesis that, independent of ceftriaxone treatment, PSU rats
would display tolerance to the ability of cocaine to induce c-Fos, we
conducted independent samples t-tests within cocaine-only and
cocaine + alcohol vehicle-treated rats, finding no significant Frontiers in Pharmacology frontiersin.org Frontiers in Pharmacology Discussion Here we report the effects of a non-contingent cocaine injection
on cellular activation in brain regions where we previously observed
different levels of c-Fos expression upon a cue + cocaine-primed
reinstatement test. We found no effects of either PSU or ceftriaxone 06 frontiersin.org Mesa et al. 10.3389/fphar.2023.1132689 FIGURE 4
c-Fos expression induced by non-contingent cocaine injection and context re-exposure. (A) In cocaine + alcohol PSU rats, the total amount of
alcohol intake positively correlated with c-Fos expression in the PL after a non-contingent cocaine injection (r = 0.6413, p > 0.01). c-Fos expression
across groups in regions of interest: (B) PL; (C) IL; (D) NA core (NAc); (E) NA shell (NAs); (F) BLA; and (G) VTA. FIGURE 4 FIGURE 4 FIGURE 4 FIGURE 4
c-Fos expression induced by non-contingent cocaine injection and context re-exposure. (A) In cocaine + alcohol PSU rats, the total amount of
alcohol intake positively correlated with c-Fos expression in the PL after a non-contingent cocaine injection (r = 0.6413, p > 0.01). c-Fos expression
across groups in regions of interest: (B) PL; (C) IL; (D) NA core (NAc); (E) NA shell (NAs); (F) BLA; and (G) VTA. TABLE 1 C-fos expression in select brain regions following a cue + cocaine-primed reinstatement test (Stennett et al., 2020) or following only cocaine + context
re-exposure (present data). Arrows refer to change in expression relative to the Coc + H2O + Veh condition. Brain region
Stennett et al. (2020)
Present data
Coc+H2O-Cef
Coc+EtOH-Veh
Coc+EtOH-Cef
Coc+H2O-Cef
Coc+EtOH-Veh
Coc+EtOH-Cef
PL
↓
↓
↔
↔
↔
↔
IL
↓
↓
↔
↔
↔
↔
NA core
↓
↓
↓
↔
↔
↔
NA shell
↓
↓
↓
↔
↔
↔
BLA
↔
↑
↑
↔
↔
↔
VTA
↑
↔
↔
↔
↔
↔ TABLE 1 C-fos expression in select brain regions following a cue + cocaine-primed reinstatement test (Stennett et al., 2020) or following only cocaine + contex
re-exposure (present data). Arrows refer to change in expression relative to the Coc + H2O + Veh condition. TABLE 1 C-fos expression in select brain regions following a cue + cocaine-primed reinstatement test (Stennett et al., 2020) or following only cocaine + context
re-exposure (present data). Arrows refer to change in expression relative to the Coc + H2O + Veh condition. Brain region
Stennett et al. Discussion (2020)
Present data
Coc+H2O-Cef
Coc+EtOH-Veh
Coc+EtOH-Cef
Coc+H2O-Cef
Coc+EtOH-Veh
Coc+EtOH-Cef
PL
↓
↓
↔
↔
↔
↔
IL
↓
↓
↔
↔
↔
↔
NA core
↓
↓
↓
↔
↔
↔
NA shell
↓
↓
↓
↔
↔
↔
BLA
↔
↑
↑
↔
↔
↔
VTA
↑
↔
↔
↔
↔
↔ c-Fos expression in the NA core, NA shell, and PL and IL cortices
and
increased
expression
in
the
BLA
relative
to
cocaine
monosubstance rats (Stennett et al., 2020). However, here, in the
absence of cocaine-associated cues and the opportunity to relapse, a
non-contingent cocaine injection produced c-Fos levels that were no
different between cocaine + alcohol PSU and cocaine-only rats in
these regions. While in the vehicle condition there were trends for
reduced c-Fos expression in the VTA and the NA shell, these
differences did not attain statistical significance. Thus, we can
conclude that the differences in c-Fos expression observed
previously after a cue + cocaine-primed reinstatement test
resulted
from
a
difference
in
neural
circuitry
mediating
reinstatement in the PSU condition, and not tolerance or treatment on cocaine-induced c-Fos expression in any brain region
examined. In the PL, greater alcohol intake was associated with
greater c-Fos expression upon non-contingent cocaine. We also
report similar behavioral findings to our previous work using a
sequential cocaine + alcohol model, with a modest increase in
cocaine intake in the PSU condition. Previous iterations of the
sequential cocaine + alcohol model did not produce detectable levels
of cocaethylene, a psychoactive metabolite formed when alcohol and
cocaine are both present in the liver, in samples of whole blood
(Stennett et al., 2020). Thus, it is unlikely that cocaethylene affected
our results. We previously found that following a cue + cocaine-primed
reinstatement test, cocaine + alcohol PSU rats demonstrate reduced 07 frontiersin.org Mesa et al. 10.3389/fphar.2023.1132689 10.3389/fphar.2023.1132689 10.3389/fphar.2023.1132689 Lastly, we previously found that cue + cocaine-primed
reinstatement induces more VTA c-Fos in cocaine-only rats that
are treated with ceftriaxone, an effect accompanied by decreased
reinstatement. Here we do not see the same effect on c-Fos
expression after non-contingent cocaine, indicating that our
previous finding was unique to the cue + cocaine-primed
reinstatement condition. Ceftriaxone does not have the same
effect on reinstatement-induced c-Fos expression in the VTA of
rats that consumed both cocaine and alcohol, nor does it attenuate
reinstatement in this condition (Stennett et al., 2020). sensitization to cocaine. Data availability statement The raw data supporting the conclusion of this article will be
made available by the authors, without undue reservation. Conclusion Here we find no evidence that sequential cocaine + alcohol
PSU produces pharmacological tolerance or sensitization to
cocaine in any brain region examined. Sequential cocaine +
alcohol
PSU
increases
PL
responding
to
non-contingent
cocaine, even in the absence of cocaine-associated
cues. Future studies should aim to identify the profiles of PL cells
altered by PSU as opposed to monosubstance use. The PL shares
reciprocal projections with the BLA, a region
that
also
experiences alcohol-related adaptations. Manipulation of BLA-
PL pathways may help further define the changes caused by
cocaine + alcohol PSU and how those changes drive seeking of
each substance individually. To that end, additional research is
needed to determine the necessity of this circuitry in the
reinstatement of cocaine-seeking in a cocaine + alcohol PSU
model. This work should include females, as all prior work on
cocaine + alcohol PSU in rodents has been conducted in males. Ethics statement Our prior work found increased reinstatement-induced BLA
c-Fos expression in the vehicle- and ceftriaxone-treated cocaine +
alcohol PSU condition relative to the cocaine-only condition
(Stennett et al., 2020). Here, we found no evidence that this arose
from pharmacological sensitization to cocaine. Thus, the BLA may
be a critical mediator of cue + cocaine-primed relapse in the PSU
condition. It is well-established that regional inactivation of
glutamatergic BLA cells impedes cue-primed reinstatement of
cocaine seeking (Grimm and See, 2000; Kruzich and See, 2001;
Kantak et al., 2002; Stefanik and Kalivas, 2013). The cytology of BLA
suggests that c-Fos expression is likely present in glutamatergic
principal neurons due to their relative abundance (McDonald, 1982;
McCool, 2021), although c-Fos is also detectable in BLA GABAergic
neurons as well (Berretta et al., 2005; Lukkes et al., 2012). Similarly,
decreasing regional glutamate neurotransmission also demonstrably
reduces alcohol seeking in rodent models (Bäckström et al., 2004;
Gass et al., 2011; Sinclair et al., 2012). Future work will test the
hypothesis that the BLA is necessary for reinstatement in the cocaine
+ alcohol condition. The animal study was reviewed and approved by the University
of Florida IACUC. Discussion See Table 1 for summary of c-fos expression
following non-contingent cocaine only and following a cue +
cocaine-primed reinstatement test. The positive correlation between alcohol intake and the number
of PL c-Fos + cells observed here suggests that alcohol consumption
modulates PL responding to the pharmacological effects of cocaine. PL activity drives reinstatement of cocaine seeking (McFarland et al.,
2003; McLaughlin and See, 2003; Stefanik et al., 2013; Mesa et al.,
2022). If a non-contingent cocaine injection promotes cocaine
seeking behaviors, PL cellular activation may serve as a precursor
to those behaviors and alcohol may alter the capacity of those cells to
respond to the cocaine experience. Pyramidal cells within PL
undergo
postsynaptic
changes
following
chronic
alcohol
exposure, particularly in layers 2 and 3, from which efferents
arise that terminate in the BLA (Gabbott et al., 2005). In mice,
PL cells that project to the telencephalon (which contains the BLA)
demonstrate greater spontaneous excitatory postsynaptic currents
and mGlu2/3-dependent plasticity after 3 weeks of IAA (Joffe et al.,
2021), a similar amount of alcohol exposure to that achieved here. Thus, acute cocaine use may act directly on excitatory PL neurons in
layer 2/3 that were modified by chronic alcohol consumption,
project to the BLA, and produce c-Fos. Of note, our study aimed
to image layers 2/3 and 5 of the PL, the latter of which also sends
projections to the BLA (Gabbott et al., 2005). Recent evidence,
however, undermines the notion that alcohol exposure increases
excitability in PL; intermittent alcohol vapor exposure did not alter
intrinsic excitability of PL pyramidal neurons that project to either
NA core or BLA and was accompanied by reduced expression of
D1 receptors in that subpopulation (Obray et al., 2022). Yet, this
work, like many other rodent studies on alcohol use, employed an
intermittent alcohol exposure model, which tends to produce
substantially higher levels of blood alcohol content than the
sequential PSU model used here (Gass et al., 2014; Stennett et al.,
2020). Thus, the effects of chronic alcohol on PL activation may be
dose- and time-dependent. Cocaine intake leads to increased PL
neuronal excitability (Nasif et al., 2005; Hearing et al., 2013; Otis
et al., 2018). More work is needed to reconcile any competing effects
of cocaine and alcohol on intrinsic excitability within the PL and the
summation of such effects in PSU. Author contributions YP-H, JM, and LK designed the studies, analyzed the data, and
wrote the manuscript. JM, YP-H, and EC collected the data. All
authors contributed to the article and approved the submitted
version. frontiersin.org Frontiers in Pharmacology References doi:10.1016/j.drugalcdep.2018.07.025 Gabbott, P. L. A., Warner, T. A., Jays, P. R. L., Salway, P., and Busby, S. J. (2005). Prefrontal cortex in the rat: Projections to subcortical autonomic, motor, and limbic
centers. J. Comp. Neurol. 492, 145–177. doi:10.1002/cne.20738 Lukkes, J. L., Burke, A. R., Zelin, N. S., Hale, M. W., and Lowry, C. A. (2012). Post-
weaning social isolation attenuates c-Fos expression in GABAergic interneurons in the
basolateral amygdala of adult female rats. Physiol. Behav. 107, 719–725. doi:10.1016/j. physbeh.2012.05.007 Gass, J. T., Glen, W. B., McGonigal, J. T., Trantham-Davidson, H., Lopez, M. F.,
Randall, P. K., et al. (2014). Adolescent alcohol exposure reduces behavioral flexibility,
promotes disinhibition, and increases resistance to extinction of ethanol self-
administration in adulthood. Neuropsychopharmacology 39, 2570–2583. doi:10.1038/
npp.2014.109 Mahler, S. V., and Aston-Jones, G. S. (2012). Fos activation of selective afferents to
ventral tegmental area during cue-induced reinstatement of cocaine seeking in rats. J. Neurosci. 32, 13309–13326. doi:10.1523/JNEUROSCI.2277-12.2012 Gass, J. T., Sinclair, C. M., Cleva, R. M., Widholm, J. J., and Olive, M. F. (2011). Alcohol-seeking behavior is associated with increased glutamate transmission
in basolateral amygdala and nucleus accumbens as measured by glutamate-
oxidase-coated biosensors. Addict. Biol. 16, 215–228. doi:10.1111/j.1369-1600. 2010.00262.x McCool, B. A. (2021). Ethanol modulation of cortico-basolateral amygdala circuits:
Neurophysiology and behavior. Neuropharmacology 197, 108750. doi:10.1016/j. neuropharm.2021.108750 McDonald, A. J. (1982). Neurons of the lateral and basolateral amygdaloid nuclei: A
golgi study in the rat. J. Comp. Neurol. 212, 293–312. doi:10.1002/cne.902120307 Griffin, W. C., Haun, H. L., Hazelbaker, C. L., Ramachandra, V. S., and Becker, H. C. (2014). Increased extracellular glutamate in the nucleus accumbens promotes excessive
ethanol drinking in ethanol dependent mice. Neuropsychopharmacology 39, 707–717. doi:10.1038/npp.2013.256 McFarland, K., Davidge, S. B., Lapish, C. C., and Kalivas, P. W. (2004). Limbic and
motor circuitry underlying footshock-induced reinstatement of cocaine-seeking
behavior. J. Neurosci. 24, 1551–1560. doi:10.1523/JNEUROSCI.4177-03.2004 Grimm, J. W., and See, R. E. (2000). Dissociation of primary and secondary reward-
relevant limbic nuclei in an animal model of relapse. Neuropsychopharmacology 22,
473–479. doi:10.1016/S0893-133X(99)00157-8 McFarland, K., Lapish, C. C., and Kalivas, P. W. (2003). Prefrontal glutamate release
into the core of the nucleus accumbens mediates cocaine-induced reinstatement of
drug-seeking behavior. J. Neurosci. 23, 3531–3537. doi:10.1523/JNEUROSCI.23-08-
03531.2003 Hearing, M., Kotecki, L., Marron Fernandez de Velasco, E., Fajardo-Serrano, A.,
Chung, H. J., Luján, R., et al. (2013). Repeated cocaine weakens GABA(B)-Girk
signaling in layer 5/6 pyramidal neurons in the prelimbic cortex. Neuron 80,
159–170. References Knackstedt, L. A., Melendez, R. I., and Kalivas, P. W. (2010). Ceftriaxone restores
glutamate homeostasis and prevents relapse to cocaine seeking. Biol. Psychiatry 67,
81–84. doi:10.1016/j.biopsych.2009.07.018 Knackstedt, L. A., Melendez, R. I., and Kalivas, P. W. (2010). Ceftriaxone restores
glutamate homeostasis and prevents relapse to cocaine seeking. Biol. Psychiatry 67,
81–84. doi:10.1016/j.biopsych.2009.07.018 Anderson, A. L., Reid, M. S., Li, S.-H., Holmes, T., Shemanski, L., Slee, A., et al. (2009). Modafinil for the treatment of cocaine dependence. Drug Alcohol Depend. 104, 133–139. doi:10.1016/j.drugalcdep.2009.04.015 Kruzich, P. J., and See, R. E. (2001). Differential contributions of the basolateral and
central amygdala in the acquisition and expression of conditioned relapse to cocaine-
seeking behavior. J. Neurosci. 21, RC155. doi:10.1523/JNEUROSCI.21-14-j0002.2001 Kruzich, P. J., and See, R. E. (2001). Differential contributions of the basolateral and
central amygdala in the acquisition and expression of conditioned relapse to cocaine-
seeking behavior. J. Neurosci. 21, RC155. doi:10.1523/JNEUROSCI.21-14-j0002.2001 Bäckström, P., Bachteler, D., Koch, S., Hyytiä, P., and Spanagel, R. (2004). mGluR5
antagonist
MPEP
reduces
ethanol-seeking
and
relapse
behavior. Neuropsychopharmacology 29, 921–928. doi:10.1038/sj.npp.1300381 Bäckström, P., Bachteler, D., Koch, S., Hyytiä, P., and Spanagel, R. (2004). mGluR5
antagonist
MPEP
reduces
ethanol-seeking
and
relapse
behavior. Neuropsychopharmacology 29, 921–928. doi:10.1038/sj.npp.1300381 Baker, D. A., McFarland, K., Lake, R. W., Shen, H., Tang, X.-C., Toda, S., et al. (2003). Neuroadaptations in cystine-glutamate exchange underlie cocaine relapse. Nat. Neurosci. 6, 743–749. doi:10.1038/nn1069 Baker, D. A., McFarland, K., Lake, R. W., Shen, H., Tang, X.-C., Toda, S., et al. (2003). Neuroadaptations in cystine-glutamate exchange underlie cocaine relapse. Nat. Neurosci. 6, 743–749. doi:10.1038/nn1069 LaCrosse, A. L., Hill, K., and Knackstedt, L. A. (2016). Ceftriaxone attenuates cocaine
relapse after abstinence through modulation of nucleus accumbens AMPA subunit
expression. Eur. Neuropsychopharmacol. 26, 186–194. doi:10.1016/j.euroneuro.2015. 12.022 Berretta, S., Pantazopoulos, H., Caldera, M., Pantazopoulos, P., and Paré, D. (2005). Infralimbic cortex activation increases c-Fos expression in intercalated neurons of the
amygdala. Neuroscience 132, 943–953. doi:10.1016/j.neuroscience.2005.01.020 Liu, Y., Elliott, A. L., Serdarevic, M., Leeman, R. F., and Cottler, L. B. (2019). A latent
class analysis of the past-30-day substance use patterns among lifetime cocaine users:
Findings from a community sample in North Central Florida. Addict. Behav. Rep. 9,
100170. doi:10.1016/j.abrep.2019.100170 DeVos, K. (2001). Cell counter. Available at: https://imagej.nih.gov/ij/plugins/cell-
counter.html (Accessed June 6, 2021). Liu, Y., Williamson, V., Setlow, B., Cottler, L. B., and Knackstedt, L. A. (2018). The
importance of considering polysubstance use: Lessons from cocaine research. Drug
Alcohol Depend. 192, 16–28. Publisher’s note authors and does not necessarily represent the official views of the
National Institutes of Health. authors and does not necessarily represent the official views of the
National Institutes of Health. All
claims
expressed
in
this
article
are
solely
those
of
the
authors
and
do
not
necessarily
represent
those
of
their
affiliated
organizations,
or
those
of
the
publisher, the editors and the reviewers. Any product that
may be evaluated in this article, or claim that may be made
by its manufacturer, is not guaranteed or endorsed by the
publisher. Funding Research reported in this publication was supported by the
National Institute On Drug Abuse of the National Institutes of
Health under Award Number R33DA045140 and DA045140-
S01 awarded to LK. The content is solely the responsibility of the 08 frontiersin.org Mesa et al. 10.3389/fphar.2023.1132689 10.3389/fphar.2023.1132689 Conflict of interest The authors declare that the research was conducted in the
absence of any commercial or financial relationships that could be
construed as a potential conflict of interest. References doi:10.1016/j.neuron.2013.07.019 McLaughlin, J., and See, R. E. (2003). Selective inactivation of the dorsomedial
prefrontal
cortex
and
the
basolateral
amygdala
attenuates
conditioned-cued
reinstatement of extinguished cocaine-seeking behavior in rats. Psychopharmacol. Berl. 168, 57–65. doi:10.1007/s00213-002-1196-x Joffe, M. E., Winder, D. G., and Conn, P. J. (2021). Increased synaptic strength and
mGlu2/3 receptor plasticity on mouse prefrontal cortex intratelencephalic pyramidal
cells following intermittent access to ethanol. Alcohol. Clin. Exp. Res. 45, 518–529. doi:10.1111/acer.14546 Mesa, J. R., Wesson, D. W., Schwendt, M., and Knackstedt, L. A. (2022). The roles of
rat medial prefrontal andorbitofrontal cortices in relapse to cocaine-seeking: A
comparison
acrossmethods
for
identifying
neurocircuits. Addict. Neurosci. 4,
100031. doi:10.1016/j.addicn.2022.100031 Kalivas, P. W. (2004). Glutamate systems in cocaine addiction. Curr. Opin. Pharmacol. 4, 23–29. doi:10.1016/j.coph.2003.11.002 Kalivas, P. W. (2004). Glutamate systems in cocaine addiction. Curr. Opin. Pharmacol. 4, 23–29. doi:10.1016/j.coph.2003.11.002 Kantak, K. M., Black, Y., Valencia, E., Green-Jordan, K., and Eichenbaum, H. B. (2002). Dissociable effects of lidocaine inactivation of the rostral and caudal basolateral
amygdala on the maintenance and reinstatement of cocaine-seeking behavior in rats. J. Neurosci. 22, 1126–1136. doi:10.1523/JNEUROSCI.22-03-01126.2002 Morelli, M., Fenu, S., Pinna, A., and Di Chiara, G. (1992). Opposite effects of NMDA
receptor blockade on dopaminergic D1-and D2-mediated behavior in the 6-
hydroxydopamine
model
of
turning:
Relationship
with
c-fos
expression. J. Pharmacol. Exp. Ther. 260, 402–408. Kantak, K. M., Black, Y., Valencia, E., Green-Jordan, K., and Eichenbaum, H. B. (2002). Dissociable effects of lidocaine inactivation of the rostral and caudal basolateral
amygdala on the maintenance and reinstatement of cocaine-seeking behavior in rats. J. Neurosci. 22, 1126–1136. doi:10.1523/JNEUROSCI.22-03-01126.2002 Kapasova, Z., and Szumlinski, K. K. (2008). Strain differences in alcohol-induced
neurochemical plasticity: A role for accumbens glutamate in alcohol intake. Alcohol
Clin. Exp. Res. 32, 617–631. doi:10.1111/j.1530-0277.2008.00620.x Kapasova, Z., and Szumlinski, K. K. (2008). Strain differences in alcohol-induced
neurochemical plasticity: A role for accumbens glutamate in alcohol intake. Alcohol
Clin. Exp. Res. 32, 617–631. doi:10.1111/j.1530-0277.2008.00620.x Müller, R., Bravo, R., Burckhardt, J., and Curran, T. (1984). Induction of c-fos gene
and protein by growth factors precedes activation of c-myc. Nature 312, 716–720. doi:10.1038/312716a0 Nasif, F. J., Sidiropoulou, K., Hu, X.-T., and White, F. J. (2005). Repeated cocaine
administration increases membrane excitability of pyramidal neurons in the rat medial
prefrontal cortex. J. Pharmacol. Exp. Ther. 312, 1305–1313. doi:10.1124/jpet.104.075184 Kedia, S., Sell, M. A., and Relyea, G. (2007). Mono-versus polydrug abuse patterns
among publicly funded clients. Subst. Abuse Treat. Prev. Policy 2, 33. Frontiers in Pharmacology References doi:10.1186/1747-
597X-2-33 Kedia, S., Sell, M. A., and Relyea, G. (2007). Mono-versus polydrug abuse patterns
among publicly funded clients. Subst. Abuse Treat. Prev. Policy 2, 33. doi:10.1186/1747-
597X-2-33 Obray, J. D., Landin, J. D., Vaughan, D. T., Scofield, M. D., and Chandler, L. J. (2022). Adolescent alcohol exposure reduces dopamine 1 receptor modulation of prelimbic
neurons projecting to the nucleus accumbens and basolateral amygdala. Addict. Neurosci. 4, 100044. doi:10.1016/j.addicn.2022.100044 Kerstetter, K. A., Wunsch, A. M., Nakata, K. G., Donckels, E., Neumaier, J. F., and
Ferguson, S. M. (2016). Corticostriatal
afferents
modulate
responsiveness
to
psychostimulant drugs and drug-associated stimuli. Neuropsychopharmacology 41,
1128–1137. doi:10.1038/npp.2015.253 Frontiers in Pharmacology 09 frontiersin.org Mesa et al. 10.3389/fphar.2023.1132689 transient synaptic potentiation and cocaine-seeking behavior. Brain Struct. Funct. 221, 1681–1689. doi:10.1007/s00429-015-0997-8 Otis, J. M., Fitzgerald, M. K., Yousuf, H., Burkard, J. L., Drake, M., and Mueller, D. (2018). Prefrontal neuronal excitability maintains cocaine-associated memory during
retrieval. Front. Behav. Neurosci. 12, 119. doi:10.3389/fnbeh.2018.00119 Stefanik, M. T., Moussawi, K., Kupchik, Y. M., Smith, K. C., Miller, R. L., Huff, M. L.,
et al. (2013). Optogenetic inhibition of cocaine seeking in rats. Addict. Biol. 18, 50–53. doi:10.1111/j.1369-1600.2012.00479.x Pati, D., Kelly, K., Stennett, B., Frazier, C. J., and Knackstedt, L. A. (2016). Alcohol
consumption increases basal extracellular glutamate in the nucleus accumbens core of
Sprague-Dawley
rats
without
increasing
spontaneous
glutamate
release. Eur. J. Neurosci. 44, 1896–1905. doi:10.1111/ejn.13284 Stennett, B. A., Frankowski, J. C., Peris, J., and Knackstedt, L. A. (2017). Ceftriaxone
reduces alcohol intake in outbred rats while upregulating xCT in the nucleus accumbens
core. Pharmacol. Biochem. Behav. 159, 18–23. doi:10.1016/j.pbb.2017.07.001 Paxinos, G., and Watson, C. (2007). The rat brain in stereotaxic coordinates. 6th ed. Cambridge, Massachusetts, United States: Elsevier Acad. Press. Stennett, B. A., and Knackstedt, L. A. (2020). A rat model of cocaine-alcohol
polysubstance use reveals altered cocaine seeking and glutamate levels in the
nucleus accumbens. Front. Neurosci. 14, 877. doi:10.3389/fnins.2020.00877 SAMHSA (2022). Key substance use and mental health disorders in the United States:
results from the 2020 national survey on drug use and Health, center for behavioral Health
Statistics and quality. Rockville, MD: Substance Abuse and Mental Health Services
Administration. Available at: https://www.samhsa.gov/data/sites/default/files/reports/
rpt35325/NSDUHFFRPDFWHTMLFiles2020/2020NSDUHFFR1PDFW102121.pdf
(Accessed June 30, 2022). Stennett, B. A., Padovan-Hernandez, Y., and Knackstedt, L. A. (2020). Sequential
cocaine-alcohol self-administration produces adaptations in rat nucleus accumbens
core glutamate homeostasis that are distinct from those produced by cocaine self-
administration alone. Neuropsychopharmacology 45, 441–450. References doi:10.1038/s41386-019-
0452-2 Sari, Y., Smith, K. D., Ali, P. K., and Rebec, G. V. (2009). Upregulation of
GLT1 attenuates cue-induced reinstatement of cocaine-seeking behavior in rats. J. Neurosci. 29, 9239–9243. doi:10.1523/JNEUROSCI.1746-09.2009 Trantham-Davidson, H., LaLumiere, R. T., Reissner, K. J., Kalivas, P. W., and
Knackstedt, L. A. (2012). Ceftriaxone normalizes nucleus accumbens synaptic
transmission, glutamate transport, and export following cocaine self-administration
and extinction training. J. Neurosci. 32, 12406–12410. doi:10.1523/JNEUROSCI.1976-
12.2012 Siemsen, B. M., Barry, S. M., Vollmer, K. M., Green, L. M., Brock, A. G., Westphal, A. M., et al. (2022). A subset of nucleus accumbens neurons receiving dense and functional
prelimbic cortical input are required for cocaine seeking. Front. Cell. Neurosci. 16,
844243. doi:10.3389/fncel.2022.844243 Wang, J. Q. (1998). Regulation of immediate early gene c-fos and zif/268 mRNA
expression in rat striatum by metabotropic glutamate receptor. Brain Res. Mol. Brain
Res. 57, 46–53. doi:10.1016/S0169-328X(98)00060-6 Sinclair, C. M., Cleva, R. M., Hood, L. E., Olive, M. F., and Gass, J. T. (2012). mGluR5 receptors in the basolateral amygdala and nucleus accumbens regulate cue-
induced reinstatement of ethanol-seeking behavior. Pharmacol. Biochem. Behav. 101,
329–335. doi:10.1016/j.pbb.2012.01.014 Weiland, A., Garcia, S., and Knackstedt, L. A. (2015). Ceftriaxone and cefazolin
attenuate the cue-primed reinstatement of alcohol-seeking. Front. Pharmacol. 6, 44. doi:10.3389/fphar.2015.00044 Smith, A. C. W., Scofield, M. D., Heinsbroek, J. A., Gipson, C. D., Neuhofer, D.,
Roberts-Wolfe, D. J., et al. (2017). Accumbens nNOS interneurons regulate cocaine
relapse. J. Neurosci. 37, 742–756. doi:10.1523/JNEUROSCI.2673-16.2016 Wright, K. N., Dossat, A. M., Strong, C. E., Sailer, L. L., Pavlock, S. M., and Kabbaj, M. (2018). Optogenetic inhibition of medial prefrontal cortex projections to the nucleus
accumbens core and methyl supplementation via L-Methionine attenuates cocaine-
primed reinstatement. Integr. Zool. 13, 795–803. doi:10.1111/1749-4877.12365 Stefanik, M. T., and Kalivas, P. W. (2013). Optogenetic dissection of basolateral
amygdala projections during cue-induced reinstatement of cocaine seeking. Front. Behav. Neurosci. 7, 213. doi:10.3389/fnbeh.2013.00213 Young, S. T., Porrino, L. J., and Iadarola, M. J. (1991). Cocaine induces striatal c-fos-
immunoreactive proteins via dopaminergic D1 receptors. Proc. Natl. Acad. Sci. U. S. A. 88, 1291–1295. doi:10.1073/pnas.88.4.1291 Stefanik, M. T., Kupchik, Y. M., and Kalivas, P. W. (2016). Optogenetic inhibition of
cortical afferents in the nucleus accumbens simultaneously prevents cue-induced 10 10 Frontiers in Pharmacology frontiersin.org
|
https://openalex.org/W861629562
|
https://europepmc.org/articles/pmc4406369?pdf=render
|
English
| null |
Relationship between seasonal respiratory allergies and cashew's pollination period in students at a university of northeast Brazil
|
The World Allergy Organization journal
| 2,015
|
cc-by
| 702
|
Pomiecinski et al. World Allergy Organization Journal 2015, 8(Suppl 1):A114
http://www.waojournal.org/content/8/S1/A114 Pomiecinski et al. World Allergy Organization Journal 2015, 8(Suppl 1):A114
http://www.waojournal.org/content/8/S1/A114 Open Access Background fungi, as in the general population. It is interesting that
35% reported worsening in the second half, of the year the
pollen season, but only 8% believe that worsen due to pol-
lination of cashew. It seems that if pollen of cashew is
actually an allergen, it would not be the only one. The
cashew is considered a heavy pollen which could not travel
long distances, but on our campus there are a large num-
ber of cashew trees. Moreover, at this time of year, we get
wind and thus more likely mites and fungi. Thus, more
data are needed to establish the relation of cause and effect
but, this study paves the way for others to assess if the
pollen cashew is a villain or even a myth in our city. Observe if students exposed to pollen cashew realize
worsening of their symptoms in the pollen season. Submit your next manuscript to BioMed Central
and take full advantage of: Submit your next manuscript to BioMed Central
and take full advantage of: and take full advantage of:
• Convenient online submission
• Thorough peer review
• No space constraints or color figure charges
• Immediate publication on acceptance
• Inclusion in PubMed, CAS, Scopus and Google Scholar
• Research which is freely available for redistribution
Submit your manuscript at
www.biomedcentral.com/submit Relationship between seasonal respiratory
allergies and cashew’s pollination period in
students at a university of northeast Brazil
Fabiane Pomiecinski*, Ana Luiza Mapurunga Gonçalves, Karen Adria Romão De Lima,
Mariana Aquino Holanda Pinto, Mariana Lustosa Farias Barros, Sarah Gomes Peixoto From 3rd WAO International Scientific Conference (WISC) 2014
Rio de Janeiro, Brazil. 6-9 December 2014 Methods Cross-sectional and descriptive study aimed at medical
students of a university in the Northeast, exposed to pol-
len cashew. An electronic questionnaire about allergic
rhinitis, allergic conjunctivitis, asthma and perception
regarding seasonality and aggravating factors was made
available for free participation in a site of the institution. © 2015 Pomiecinski et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Results The questionnaire was answered by a total of 108
students, aged 16-40 years, 80% (84) between 19-25
years. Of the total, 68% (73) reported symptoms of aller-
gic rhinitis, and 70% (52) intermittent rhinitis and 65%
(48) had moderate to severe. 40% (43) reported having
allergic conjunctivitis, intermittent was the majority
(77%), being ocular pruritus the main symptom. Of the
total, 17% (18) said they experience symptoms of asthma,
75% intermittent asthma. 33% had worsening of symp-
toms in the second half of the year. As to the triggering
factors, about 30% reported worsening with dust and
mold, and 8% believe that pollination of cashew aggra-
vates their symptoms. Published: 8 April 2015 doi:10.1186/1939-4551-8-S1-A114
Cite this article as: Pomiecinski et al.: Relationship between seasonal
respiratory allergies and cashew’s pollination period in students at a
university of northeast Brazil. World Allergy Organization Journal 2015
8(Suppl 1):A114. doi:10.1186/1939-4551-8-S1-A114
Cite this article as: Pomiecinski et al.: Relationship between seasonal
respiratory allergies and cashew’s pollination period in students at a
university of northeast Brazil. World Allergy Organization Journal 2015
8(Suppl 1):A114. Conclusions The prevalence of allergic rhinitis (68%) and asthma (17%)
was above that found in the general population is 30% and
12% respectively, however, we have to take into account
the selection bias. Most realize worsens with mites and Universidade De Fortaleza – Unifor, Brazil Universidade De Fortaleza – Unifor, Brazil © 2015 Pomiecinski et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
|
https://openalex.org/W4393442998
|
https://www.frontiersin.org/articles/10.3389/fenvs.2024.1346469/pdf?isPublishedV2=False
|
English
| null |
Main influencing factors of terrestrial evapotranspiration for different land cover types over the Tibetan Plateau in 1982–2014
|
Frontiers in environmental science
| 2,024
|
cc-by
| 11,322
|
TYPE Original Research
PUBLISHED 02 April 2024
DOI 10.3389/fenvs.2024.1346469 TYPE Original Research
PUBLISHED 02 April 2024
DOI 10.3389/fenvs.2024.1346469 TYPE Original Research
PUBLISHED 02 April 2024
DOI 10.3389/fenvs.2024.1346469 COPYRIGHT
© 2024 Li, Pan and Zhao. This is an open-access
article distributed under the terms of the
Creative Commons Attribution License (CC BY).
The use, distribution or reproduction in other
forums is permitted, provided the original
author(s) and the copyright owner(s) are
credited and that the original publication in this
journal is cited, in accordance with accepted
academic practice. No use, distribution or
reproduction is permitted which does not
comply with these terms. OPEN ACCESS OPEN ACCESS
EDITED BY
Devaraju Narayanappa,
CSC—IT Center for Science, Finland
REVIEWED BY
Wanqiu Xing,
Hohai University, China
Preet Lal,
Michigan State University, United States
*CORRESPONDENCE
Yongjie Pan,
panyongjie@lzb.ac.cn
RECEIVED 29 November 2023
ACCEPTED 14 March 2024
PUBLISHED 02 April 2024
CITATION
Li X, Pan Y and Zhao C (2024), Main influenc
factors of terrestrial evapotranspiration for
different land cover types over the Tibetan
Plateau in 1982–2014. F
t E
i
S i 12 1346469 EDITED BY
Devaraju Narayanappa,
CSC—IT Center for Science, Finland Wanqiu Xing,
Hohai University, China
Preet Lal,
Michigan State University, United States
*CORRESPONDENCE
Yongjie Pan,
panyongjie@lzb.ac.cn
RECEIVED 29 November 2023
ACCEPTED 14 March 2024
PUBLISHED 02 April 2024 Xia Li 1, Yongjie Pan 1* and Cailing Zhao2 1Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions, Northwest
Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China, 2Institute
of Arid Meteorology, China Meteorological Administration, Lanzhou, China Introduction: Terrestrial evapotranspiration (ET) over the Tibetan Plateau (TP) has
important implications for the global water cycle, climate change, and ecosystem,
and its changes and driving factors have drawn increasing attention. Previous
research studies have minimally quantified the effects and identified the pathways
of the influencing factors on ET over different land surface types. Li X, Pan Y and Zhao C (2024), Main influencing
factors of terrestrial evapotranspiration for
different land cover types over the Tibetan
Plateau in 1982–2014. Front. Environ. Sci. 12:1346469. doi: 10.3389/fenvs.2024.1346469 Methods: In this study, we analyze the spatiotemporal distribution and variation
of ET over the TP in 1982–2014 based on multiple datasets. Furthermore, the
effects of each influencing factor on ET are quantified over different land surface
types, and the major influencing factors and their affecting pathways are
identified using structure equation modeling (SEM), which is a statistical
method used to analyze relationships among multiple variables. Frontiers in Environmental Science KEYWORDS 1 Introduction Under these climatic and environmental changes, ET has also
changed significantly (Lal et al., 2023). The difference between Pre
and ET over the TP determines the availability of freshwater for
over two billion people downstream (Ma and Zhang, 2022). Therefore, it is crucial to clarify the changes and mechanisms of
ET over the TP to not only understand the impact of the TP on
weather and climate (He et al., 2019; Wang et al., 2020) but also to
map
sustainable
water
resource
strategies
and
establish
appropriate ecoregions for Asia (Ndehedehe et al., 2018; Wang
et al., 2021). In this study, we analyzed the spatiotemporal characteristics of
ET in different land surface types over the TP from 1982 to
2014 based on multiple datasets. Meanwhile, the accuracy of
these datasets was evaluated based on observations from nine
sites to select one for further analysis. Finally, based on the ET
dataset selected from the evaluation, the contribution of each
influencing factor to ET was quantified, and the main influencing
factors and their impact pathways were identified using structure
equation modeling (SEM), which is a statistical method used to
study the relationships of multiple variables. The ET characteristics of the TP have gained increasing
attention worldwide in recent years. Studies have indicated that
the annual ET in the southeastern region of the TP was larger than
that in the northwestern region, with a variable spatial average
ranging from 294.21 mm a−1 to 377 mm a−1 (Zhang et al., 2017;
Wang et al., 2020; Ma and Zhang, 2022; Zhang et al., 2022). As for
the ET trend, some studies reported that the average ET over the TP
showed an increasing trend in recent decades (Zhang et al., 2018;
Cui et al., 2019). However, there were significant regional differences
in the spatial distribution of the ET trend among different studies. Cui et al. (2019) presented that the increased ET trend mainly
occurred in the Ali, Lhasa Valley, and Haibei areas, while the
decreased ET trend mainly occurred in the southern TP Valley. According to other studies, the most substantially increased ET
trend occurred in the southeastern TP, particularly in the forest and
alpine meadow regions (Lin et al., 2021; Zhang et al., 2022). However, some other studies even reported that the domain-
averaged ET decreased slightly over the TP (Han et al., 2021). 1 Introduction (2017) noted the importance of the leaf-area index in ET
changes in moist regions. The TP exhibits a unique geography, with
a distinct climate gradient from the northwest to the southeast. Additionally, its surface is heterogeneous. Therefore, it was
understandable that the characteristics of ET and its main
influencing factors varied in different regions across the TP, as
reported by previous studies. It is important to note that the land
cover types on the TP are also diverse, including bare soil, grassland,
meadows, and forests, from the northwestern to the southeastern
regions (Figure 1). To formulate appropriate ecological and
environmental protection policies for each land cover type and
rationalize water resource usage, it is crucial to understand the
variation of ET and the primary influencing factors and mechanisms
in each land cover type. Previous studies have extensively examined
the spatiotemporal characteristics of ET and its main influencing
factors. However, limited research has been conducted on the
primary influencing pathway and quantifying the impacts of the
influencing factors on ET in different land cover types over the TP. Evapotranspiration (ET) refers to the turbulent flux of water
vapor from the land surface into the atmosphere, involving soil
evaporation, interception from the canopy, and transpiration
through plant stomata (Chen et al., 2021). It is a key linkage
between the water and energy cycle processes of the land surface
(Zhang et al., 2016; Lian et al., 2018; Wang et al., 2021). More than
60% of precipitation (Pre) falling on the land surface is consumed by
ET per year (Pan et al., 2020). Additionally, ET plays a vital role in
modulating regional and global weather and climate (Han et al.,
2021). Therefore, it is of great significance to investigate the
spatiotemporal
characteristics
of
ET
and
its
response
to
environmental changes, especially in regions that are most
sensitive
and
vulnerable
to
climate
changes,
including
the
Tibetan Plateau (TP). The TP is the birthplace of Asia’s major rivers, famous as the
“Water Tower of Asia,” which plays a crucial role in the energy and
water cycles of Asia (Immerzeel et al., 2010; Yao et al., 2012). Over
the past decades, the TP has undergone significant warming (Yao
et al., 2019), wind stilling (Li et al., 2018; Zhang and Wang, 2020),
wetting (Sun et al., 2020), and vegetation greening (Li et al., 2018). COPYRIGHT COPYRIGHT
© 2024 Li, Pan and Zhao. This is an open-access
article distributed under the terms of the
Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other
forums is permitted, provided the original
author(s) and the copyright owner(s) are
credited and that the original publication in this
journal is cited, in accordance with accepted
academic practice. No use, distribution or
reproduction is permitted which does not
comply with these terms. Results: The results show that the climatology of ET decreases gradually from
southeastern to northwestern TP, with the maximum spatial averaged value of
379.979 ± 0.417 mm a−1 for the fifth generation of European Reanalysis (ERA5)
and the minimum of 249.899 ± 0.469 mm a−1 for the Global Land Data
Assimilation System (GLDAS). The most significant differences among the ET
datasets mainly occur in the summer. The annual ET averaged over the TP
presents an increased trend from 1982 to 2014, as shown by all of the ET
datasets. However, there are larger discrepancies in the spatial distribution of
the increased trend for these datasets. The assessment result shows that
the 0.05° land evapotranspiration dataset for the Qinghai–Tibet Plateau
(LEDQTP) has the highest temporal correlation coefficient (0.80) and the
smallest root-mean-square error (23.50 mm) compared to the observations. Based on LEDQTP, we find that precipitation is the main influencing factor of
ET, which primarily affects ET through direct pathways in bare soil and grassland
regions, with standardized estimates of 0.521 and 0.606, respectively. However,
in meadow and shrub and forest regions, the primary factor influencing ET is air
temperature, which is primarily affected by an indirect pathway through a vapor
pressure deficit. Air temperature is also the controlling factor in sparse vegetation
regions, but it affects ET through a direct pathway. Discussion: This study may provide some new useful information on the effects
of climate change on ET in different land cover types over the TP. terrestrial evapotranspiration, impact pathways, land cover types, SEM, Tibetan Plateau Frontiers in Environmental Science 01 Frontiers in Environmental Science frontiersin.org Li et al. Li et al. 10.3389/fenvs.2024.1346469 Frontiers in Environmental Science 1 Introduction These discrepancies may be due to differences in the datasets or
study periods used. Therefore, the selection of the appropriate
dataset
based
on
observations
is
crucial
for
studying
the
characteristics of ET over the TP. 1 Introduction surface net radiation (Rn) were important factors influencing the
temporal variations in ET over the TP (Wang et al., 2020). Ma and
Zhang (2022) showed that precipitation was the main driver
regulating ET trends across most of the TP. Additionally, they
found significant spatial differences in the main influencing
factors affecting ET. Zou et al. (2018) demonstrated a significant
correlation between ET and Rn and Ta in the Nagqu River basin in
the TP. According to Lin et al. (2021), the controlling factor of ET in
the humid areas of the TP was available energy, while in arid areas,
energy and water factors together dominated the ET changes. Song
et al. (2017) noted the importance of the leaf-area index in ET
changes in moist regions. The TP exhibits a unique geography, with
a distinct climate gradient from the northwest to the southeast. Additionally, its surface is heterogeneous. Therefore, it was
understandable that the characteristics of ET and its main
influencing factors varied in different regions across the TP, as
reported by previous studies. It is important to note that the land
cover types on the TP are also diverse, including bare soil, grassland,
meadows, and forests, from the northwestern to the southeastern
regions (Figure 1). To formulate appropriate ecological and
environmental protection policies for each land cover type and
rationalize water resource usage, it is crucial to understand the
variation of ET and the primary influencing factors and mechanisms
in each land cover type. Previous studies have extensively examined
the spatiotemporal characteristics of ET and its main influencing
factors. However, limited research has been conducted on the
primary influencing pathway and quantifying the impacts of the
influencing factors on ET in different land cover types over the TP. surface net radiation (Rn) were important factors influencing the
temporal variations in ET over the TP (Wang et al., 2020). Ma and
Zhang (2022) showed that precipitation was the main driver
regulating ET trends across most of the TP. Additionally, they
found significant spatial differences in the main influencing
factors affecting ET. Zou et al. (2018) demonstrated a significant
correlation between ET and Rn and Ta in the Nagqu River basin in
the TP. According to Lin et al. (2021), the controlling factor of ET in
the humid areas of the TP was available energy, while in arid areas,
energy and water factors together dominated the ET changes. Song
et al. frontiersin.org Frontiers in Environmental Science 2.1.1 ET datasets The spatial resolutions, temporal resolutions, time periods, and
sources of the ET datasets used in this study are summarized in
Table 1. The Global Land Evaporation Amsterdam Model (GLEAM)
was a set of algorithms that were based on satellite observations and
estimated
the
different
parts
of
ET
separately,
including
transpiration,
interception loss,
bare soil evaporation,
snow
sublimation, and open-water evaporation (Miralles et al., 2011;
Martens et al., 2017). The basic principle of GLEAM was to
retain the effective information from satellite observation to the
maximum extent in order to keep the ET data as observation-based
as possible (Liu et al., 2021b). Micro-derived soil moisture (SM) was
used, and vegetation interception was fully considered, which were
the advantages of GLEAM (Pan et al., 2020). Many previous studies Identifying the primary drivers of ET and the mechanisms that
influence it will aid in comprehending its response to climate
change. Several studies have investigated the factors that impact
ET on the TP. It has been found that air temperature (Ta) and 02 frontiersin.org Li et al. Li et al. 10.3389/fenvs.2024.1346469 FIGURE 1
Distribution of the major land cover types over the TP and locations of the nine eddy-covariance observation sites, including the Muztagh Ata
Westerly Observation and Research Station, Chinese Academy of Sciences (MAWORS, CAS); the Ngari Desert Observation and Research Station, CAS
(NADORS); the BJ site of Nagqu Station of Plateau Climate and Environment, CAS (BJ); the Nam Co Monitoring and Research Station for Multisphere
Interactions, CAS (NAMORS); the Qomolangma Atmospheric and Environmental Observation and Research Station, CAS (QOMS); and the Southeast
Tibet Observation and Research Station for the Alpine Environment, CAS (SETORS); Dangxiong (DX); Haibei (HBGCT1 and HBGCT2 with different land
cover types) stations. FIGURE 1
Distribution of the major land cover types over the TP and locations of the nine eddy-covariance observation sites, including the Muztagh Ata
Westerly Observation and Research Station, Chinese Academy of Sciences (MAWORS, CAS); the Ngari Desert Observation and Research Station, CAS
(NADORS); the BJ site of Nagqu Station of Plateau Climate and Environment, CAS (BJ); the Nam Co Monitoring and Research Station for Multisphere
Interactions, CAS (NAMORS); the Qomolangma Atmospheric and Environmental Observation and Research Station, CAS (QOMS); and the Southeast
Tibet Observation and Research Station for the Alpine Environment, CAS (SETORS); Dangxiong (DX); Haibei (HBGCT1 and HBGCT2 with different land
cover types) stations. TABLE 1 Information of the datasets used in the study. 2.1.1 ET datasets TABLE 1 Information of the datasets used in the study. TABLE 1 Information of the datasets used in the study. Variable
Spatial resolution
Temporal resolution
Time period (year)
Dataset and data source
ET
0.25° × 0.25°
Monthly
1980–2020
Global Land Evaporation Amsterdam Model
(GLEAM v3.5a)
0.05° × 0.05°
Monthly
1982–2016
A 0.05° Land Evapotranspiration Dataset for the
Qinghai-Tibet Plateau (LEDQTP), National
Cryosphere Desert Data Center
0.25° × 0.25°
Monthly
1948–2014
The Global Land Data Assimilation System (GLDAS-
2.0 Noah)
0.1°×0.1°
Monthly
1950–present
The European Center for Medium-Range Weather
Forecasts (ECMWF) Reanalysis v5 (ERA5)
0.5° × 0.625°
Monthly
1980–2023
The Modern-Era Retrospective Analysis for Research
and Applications, Version 2 (MERRA-2)
Ta and Pre
0.5° × 0.5°
Monthly
1961–present
China Surface Temperature/Precipitation 0.5 ° × 0.5 °
Grid Dataset (V2.0), China Meteorological Data
Service Center
Ts and SM
0.25° × 0.25°
Monthly
1948–2014
Global Land Data Assimilation System (GLDAS-
2.0 Noah)
Win, Rs, Prs, and RH
0.1°×0.1°
Monthly
1979–2018
China Meteorological Forcing Dataset (CMFD), the
National Tibetan Plateau Data Center (TPDC)
NDVI
0.083° × 0.083°
Monthly
1982–2015
Normalized Difference Vegetation Index (NDVI)
dataset of Tibetan Plateau, the National Tibetan
Plateau Data Center (TPDC) have intensively evaluated the GLEAM data and proved their high
quality (López et al., 2017; Bai and Liu, 2018). stations
across
the
TP. The
model
forcing
data
included
meteorological variables, leaf-area index from remote sensing,
albedo, and emissivity. More detailed information of the dataset
was described by Ma and Zhang (2022). The dataset was provided by
the National Cryosphere Desert Data Center (http://www.ncdc. ac.cn). A 0.05° land evapotranspiration dataset for the Qinghai–Tibet
Plateau (LEDQTP) was generated using the remote sensing-based
water-carbon coupled model PML_V2, which was calibrated and
validated by the observed ET and carbon fluxes data from 14 EC 03 frontiersin.org Li et al. 10.3389/fenvs.2024.1346469 The scientists at the National Oceanic and Atmospheric
Administration (NOAA), National Centers for Environmental
Prediction (NCEP), and the National Aeronautics and Space
Administration (NASA) Goodard Space Flight Center (GSFC)
have jointly established the Global Land Data Assimilation
System (GLDAS), which provides high-resolution global data
through integrating ground-based and satellite-based observations
using data assimilation techniques and land surface models (Rodell
et al., 2004). Different land surface models, including Mosaic, Noah,
CLM, and VIC, were used in GLDAS, with only Noah continuing to
be updated until now. the GIMMS AVHRR sensor. 2.1.2 Hydrometeorological parameters The variables that might affect ET are also listed in Table 1. The
gridded Ta and Pre datasets were provided by the China
Meteorological Data Service Center (http://data.cma.cn/), which
were generated through the thin-plate smoothing spline method
based on Ta observations from 2,472 stations and Pre observations
from 2,416 stations in China. The gridded wind speed (Win),
downward shortwave radiation (Rs), relative humidity (RH), and
surface pressure (Prs) used to calculate the vapor pressure deficit
(VPD) were from the China Meteorological Forcing Dataset
(CMFD), which was developed by He et al. (2020) and could be
downloaded
from
the
National
Tibetan
Plateau/Third
Pole
Environment
Data
Center
(https://www.tpdc.ac.cn/en/). The
dataset was created through the fusion of remote sensing
products, reanalysis datasets, and in situ observation data at
weather stations. A wide range of studies suggested that CMFD
presented
reasonable
consistency
with
ground-measured
meteorological data and was, therefore, a reliable gridded dataset
in China (Chen et al., 2011; Sun et al., 2017; Yang et al., 2017; Ma
et al., 2019). The land surface temperature (Ts) and SM were from
GLDAS-2.0 Noah. The normalized difference vegetation index
(NDVI) dataset utilized in this study was accessible at http://data. tpdc.ac.cn and was generated from the NDVI 3 g product based on The nine observation sites are located in the meadow (DX, BJ,
and SETORS), grassland (NAMORS), wetland (HBGCT2), desert
(QOMS, NADORS, and MAWORS), and shrub (HBGCT1) regions
(Table 2) so they can represent the land surface types over the TP. 2.1.1 ET datasets This product was computed from the
reflectance of the infrared and near-infrared channels (Pinzon and
Tucker, 2014) and has been proven to have good suitability and
reliable accuracy for detecting vegetation changes in the plateau
region (Zhao et al., 2021). 2.1.3 Eddy-covariance observed data The
evaluation findings indicated that ERA5 exhibited lower absolute
biases in surface latent heat flux compared to ERA-Interim (Martens
et al., 2020). The Modern-Era Retrospective Analysis for Research and
Applications,
version
2
(MERRA-2),
was
an
improved
atmospheric
reanalysis
dataset
and
the
second
version
of
MERRA. It incorporated a larger volume of satellite data and
included new observation types, such as hyperspectral radiation,
microwaves, and aerosols. In addition, it integrated satellite and
conventional weather observations with simulated atmospheric
behavior to achieve the most optimal possible estimation of the
Earth’s system state (Gelaro et al., 2017; Lu et al., 2021). Previous
research has demonstrated that the mean absolute error of latent
heat for MERRA-2 was lower than MERRA (Bosilovich et al., 2015). Frontiers in Environmental Science 2.1.3 Eddy-covariance observed data The eddy-covariance-observed latent heat flux was widely used
by researchers to evaluate ET datasets and validate ET models. Therefore, we also used the observations from nine EC stations to
evaluate the ET datasets. The detailed information and geographical
location of these sites are shown in Table 2 and Figure 1, respectively. The observations of the BJ site of Nagqu station of the Plateau
Climate and Environment (BJ), the Southeast Tibet Observation and
Research Station for the Alpine Environment (SETORS), the Nam
Co Monitoring and Research Station for Multisphere Interactions
(NAMORS), the Qomolangma Atmospheric and Environmental
Observation and Research Station (QOMS), the Ngari Desert
Observation and Research Station (NADORS), and the Muztagh
Ata Westerly Observation and Research Station (MAWORS) sites
were
downloaded
at
https://www.scidb.cn/en/. The
temporal
resolutions of the original data from these six sites were hourly. Therefore, we first processed the hourly data into daily data and then
further processed the daily data into monthly data. There were
missing values in the downloaded raw data, so we assigned the data
of a day as a missing value if the missing values of that day were more
than 80% in the generation process of daily data; otherwise, the
missing values were ignored. Similarly, during the generation of
monthly data, if 80% of the days in a month had missing values, the
value for that month was assigned as missing values; otherwise, the
missing values were ignored. The more detailed information about
the six stations was shown in Ma et al. (2020). In addition, the
observations of the Dangxiong (DX) and Haibei (HBGCT1 and
HBGCT2) sites were downloaded from the National Ecosystem
Science Data Center (http://www.nesdc.org.cn/). The details of the
observations were described by Yu et al. (2006). The data from these
three sites has already been processed into monthly values provided
by the data provider, so we just downloaded and used them directly. The fifth generation of European Reanalysis (ERA5) was also a
widely used dataset globally. Compared to the previous ERA-
Interim, ERA5 has upgraded some of its key climatic information
and applied the latest version of the Earth system model and data
assimilation techniques used at ECMWF. These updates included
more sophisticated parameterization of geophysical processes
(Hersbach et al., 2020; Lu et al., 2021). Additionally, ERA5 had
improvements in both temporal and spatial resolutions and a better
balance of global Pre and evaporation (Albergel et al., 2018). 2.2 Methods For compatibility in all of the datasets, a common period of
1982–2014 was used for analysis in the study. In addition, the
bilinear interpolation method, a commonly used interpolation
approach, was used to unify the spatial resolution of different
datasets into 0.05° × 0.05°. The temporal correlation coefficients
(TCCs) and root-mean-square error (RMSE) were used to evaluate
the ET datasets. The TCC was calculated as follows: TCC
n
i1
xi −x
(
) yi −y
n
i1
xi −x
(
)2
n
i1
yi −y
2
,
(1) (1) 04 frontiersin.org Li et al. Li et al. 10.3389/fenvs.2024.1346469 ABLE 2 Information of the eddy-covariance observation sites. TABLE 2 Information of the eddy-covariance observation sites. Code
Longitude
Latitude
Temporal
resolution
Time period
(year)
Vegetation
type
DX
91.08°
30.85°
Monthly
2004–2010
Meadow
HBGCT1
101.33°
37.67°
Monthly
2003–2010
Shrub
HBGCT2
101.32°
37.62°
Monthly
2004–2009
Wetland
BJ
91.90°
31.37°
Hourly
2010–2016
Meadow
QOMS
86.95°
28.36°
Hourly
2007–2016
Desert
SETORS
94.74°
29.77°
Hourly
2007–2016
Meadow
NADORS
79.70°
33.39°
Hourly
2010–2016
Desert
MAWORS
75.03°
38.42°
Hourly
2012–2016
Desert
NAMORS
90.96°
30.77°
Hourly
2005–2016
Grassland ERA5, and MERRA-2 are higher at most grid points compared
to the other datasets. However, the mean ET from ERA5 averaged
over the TP is the largest at 379.979 ± 0.417 mm a−1 due to the larger
discreteness of ET observed in LEDQTP and MERRA-2, particularly
for MERRA-2. GLDAS presents the smallest mean ET value of
249.90 ± 0.469 mm a−1, averaged over the TP (Table 3). where TCC was the Pearson’s correlation coefficient, x and y
represented
the
observations
and
variables
to
be
assessed,
respectively, and n was the number of months in this paper. The
RMSE was calculated as follows: RMSE
1
n
n
i1
yi −xi
2
,
(2) (2) In addition, ET over the TP presents a clear seasonal cycle,
gradually increasing from January and reaching its maximum in July
before decreasing, as shown by all the datasets (Figure 3). Furthermore, as ET increases, the differences among the datasets
become more pronounced. In June, July, and August, ERA5 shows
significantly higher ET compared to the other datasets, followed by
LEDQTP, while GLDAS has the lowest value. Therefore, the
discrepancies in annual ET among the five datasets are primarily
caused by the differences in summer. 2.2 Methods Nevertheless, all of the datasets
can consistently demonstrate the spatial and seasonal distribution
characteristics of ET over the TP in 1982–2014. where n, x, and y had the same meaning as previously defined. The
two statistics were calculated using NCAR Command Language
(NCL) version 6.6.2. Then, the t-test was used to examine the
significance of the correlation coefficients. In addition, the linear
trend of ET was also calculated using NCL. SEM, a statistical
technique widely used to test and assess causal relationships
among climate system variables (Pan et al., 2022), was utilized to
analyze the pathways of the influencing factors on ET. The direct
and indirect impact factors were distinguished in the SEM analysis. The SEM analysis was carried out using R version 4.2.3 with the
“lavaan” package. The Rn was calculated using the radiation
calculation formulas (Allen et al., 1998) based on the Rs
in the CMFD. Figure 4 shows the inter-annual variations as well as the spatial
distribution of the linear trends of ET for the five datasets from
1982 to 2014. Each dataset exhibits an increasing ET trend, with
GLEAM showing the most significant increase at a rate of 10.8 mm
(10a)−1, followed by LEDQTP. The ET trends for GLEAM,
LEDQTP, and MERRA-2 are statistically significant at a p-value
of less than 0.05. GLDAS, however, shows the minimum variation
with a change rate of 3 mm (10a)−1, which does not pass the
significance test (Figure 4F). Lin et al. (2021) and Yin et al. (2013) have also reported an increase in ET over the TP during
the periods of 1961–2014 and 1981–2010, respectively. Conversely,
Han et al. (2021) and Song et al. (2017) have shown that the annual
ET averaged over the TP decreased in 2001–2018 and 2000–2010. The inconsistency in the study time period may be the primary
reason for the opposing ET trends. Frontiers in Environmental Science frontiersin.org 3 Results The spatial distributions of annual ET for the five datasets in
1982–2014 are presented in Figure 2. All datasets exhibit a gradual
decrease in ET from the southeastern to the northwestern region of
the TP, with the lowest values concentrated primarily in the Qaidam
basin. A similar ET distribution pattern in the TP was also identified
by Ma and Zhang (2022). It is noteworthy that the spatial
distribution characteristic for ERA5 (Figure 2D) differs from that
of the other datasets due to the larger ET values in the northwestern
regions. Additionally, ET in the northwestern TP for GLDAS
(Figure 2C) and MERRA-2 (Figure 2E) is significantly smaller
than that for GLEAM (Figure 2A) and LEDQTP (Figure 2B). From Figure 2F, it can be seen that ET values for LEDQTP, Spatially, ET for all five datasets presents an increasing trend in
most areas of the TP in 1982–2014 (Figure 4A–e). However, there
are some disparities in the spatial distribution patterns of the ET
trends among the five datasets. The increasing ET trends for
GELAM are mainly distributed in the western and northern
regions of the TP, which pass the significance test at p < 0.001 in
some areas, while the decreasing ET trends are mainly distributed in
the southeastern regions, Qaidam basin, and Karakoram Mountain Frontiers in Environmental Science 05 frontiersin.org Li et al. 10.3389/fenvs.2024.1346469 FIGURE 2
Spatial distributions of the annual ET (unit: mm a−1) for (A) GLEAM, (B) LEDQTP, (C) GLDAS, (D) ERA5, and (E) MERRA-2 and (F) the boxplot of annual
ET (unit: mm) for the five datasets during 1982–2014. FIGURE 2
Spatial distributions of the annual ET (unit: mm a−1) for (A) GLEAM, (B) LEDQTP, (C) GLDAS, (D) ERA5, and (E) MERRA-2 and (F) the boxplot of annual
ET (unit: mm) for the five datasets during 1982–2014. FIGURE 2
Spatial distributions of the annual ET (unit: mm a−1) for (A) GLEAM, (B) LEDQTP, (C) GLDAS, (D) ERA5, and (E) MERRA-2 and (F) the boxplot of annual
ET (unit: mm) for the five datasets during 1982–2014. northern and southern edge regions of the TP (Figure 4C). The
decreasing ET trends for ERA5 are mainly in the Qaidam basin,
Nyingchi Tanggula, and Yarlung Tsangpo River regions and Daxue
Mountain and Qionglai Mountain regions (Figure 4D). 3 Results The
increasing trend of ET for MERRA-2 is more significant, and the
range distribution with an increasing trend is wider compared to the
other datasets (Figure 4E). TABLE 3 Annual mean ET averaged over the TP during 1982–2014 for the
five datasets (unit: mm a−1). range (Figure 4A). The spatial distribution pattern of the ET trend
for LEDQTP shows a more substantial increase compared to that for
GLEAM
(Figure
4B). The
decreasing
trend
is
sporadically
distributed in the northeastern regions, southern fringes, and
southeastern regions of the TP. Yang et al. (2022) pointed out
that the enhanced Indian monsoon significantly increased the
temperature, which induced the depletion of SM and, thus,
reduced ET in the southeastern region of the TP. As for GLDAS,
regions with a decreasing ET trend are mainly located in the Frontiers in Environmental Science frontiersin.org 3.2 Evaluation of the ET datasets based on
observations Although all five datasets exhibit an increasing trend in ET over
the TP from 1982 to 2014, there are discrepancies in the spatial
distribution patterns of ET trends in these datasets. Therefore, it is
essential to assess these datasets and select the one that is most 06 frontiersin.org Li et al. 10.3389/fenvs.2024.1346469 FIGURE 3
Monthly ET (unit: mm) averaged over the TP for the five datasets during 1982–2014. FIGURE 3
Monthly ET (unit: mm) averaged over the TP for the five datasets during 1982–2014. particularly in the summer, compared to the observations at the DX
site (Figure 5A). Similar deviations also occur at other sites,
especially
at
HBGCT1
(Figure
5B),
BJ
(Figure
5D),
and
MAWORS (Figure 5G). The RMSE between the five datasets and
observations is shown in Table 5. The RMSE between LEDQTP and
the observations is lowest at the DX, HBGCT1, HBGCT2, and BJ
sites, with values of 17.618, 27.705, 13.037, and 22.448 mm,
respectively, compared to the other datasets. At the QOM,
SETORS, and NAMORS sites, the lowest RMSE occurs between
the observations and GLEAM, GLDAS, and MERRA-2, respectively. The two sites (MAWORS and NADORS) have the lowest RMSE
between ERA5 and observations. The LEDQTP has the lowest error
between
observations,
with
an
RMSE
of
23.501 mm
when
considering the mean results averaged over all the sites. closely aligned with the observation before proceeding with
further analyses. Figure 5 displays the variation of monthly ET for the five datasets
and the observed latent heat flux at the nine observation sites during
the corresponding years. All datasets are able to capture the oscillatory
characteristics of the observations over time at most sites, except for
certain periods at specific sites, such as at the MAWORS site in 2014
(Figure 5G), which may have resulted from the high number of
missing values for observations during the period at the site. Table 4
shows the TCC between ET for the five datasets and observations at
each site. It can be seen that almost all the TCC for these datasets pass
the significance test at p < 0.001, with the exception of GLDAS at
MAWORS. Specifically, the correlations between GLEAM and the
observation at the HBGCT1 and NADORS sites are larger compared
to the other datasets, with a TCC of 0.798 and 0.808, respectively. 3.2 Evaluation of the ET datasets based on
observations It is
worth noting that the TCC between LEDQTP and the observation is
larger than the other datasets at four sites, namely, DX, HBGCT2,
QOM, and MAWORS, with values of 0.909, 0.944, 0.847, and 0.726,
respectively. The highest TCC between GLDAS, ERA5, and MERRA-
2 and the observations only appear at the SETORS, BJ, and NAMORS
sites, respectively. In terms of the average across all the sites, the
highest correlation relationship is found between LEDQTP and the
observation, with a correlation coefficient of 0.8, followed by GLEAM. Despite the strong temporal correlation between these datasets In summary, since the temporal correlation between ET for
LEDQTP and the observations is the highest and, at the same time,
that for RMSE is the lowest, we chose the LEDQTP dataset to study
the main influencing factors on the variation of ET over the TP in
the following section. Frontiers in Environmental Science frontiersin.org 3.3 Analysis of the influencing factors of the
ET changes Despite the strong temporal correlation between these datasets
and observations, there are still some errors between them, as shown
in Figure 5. All five datasets underestimate ET in certain periods, ET can be affected by various factors, such as climatic variables
and vegetation. Moreover, the main factors that cause changes in ET 07 frontiersin.org Li et al. 10.3389/fenvs.2024.1346469 FIGURE 4
Spatial distribution of linear trends (mm (10a)−1) of annual ET for (A) GLEAM, (B) LEDQTP, (C) GLDAS, (D) ERA5, and (E) MERRA-2 and (F) the inter-
annual variations of ET averaged over the TP for the five datasets during 1982–2014. The areas with black dots in (A–E) represent the linear trends that
pass the significance test at p < 0.001. FIGURE 4
Spatial distribution of linear trends (mm (10a)−1) of annual ET for (A) GLEAM, (B) LEDQTP, (C) GLDAS, (D) ERA5, and (E) MERRA-2 and (F) the inter-
annual variations of ET averaged over the TP for the five datasets during 1982–2014. The areas with black dots in (A–E) represent the linear trends that
pass the significance test at p < 0.001. FIGURE 4
Spatial distribution of linear trends (mm (10a)−1) of annual ET for (A) GLEAM, (B) LEDQTP, (C) GLDAS, (D) ERA5, and (E) MERRA-2 and (F) the inter-
annual variations of ET averaged over the TP for the five datasets during 1982–2014. The areas with black dots in (A–E) represent the linear trends that
pass the significance test at p < 0.001. may be different for different land cover types. Therefore, we
conducted SEM analyses using annual ET and its relevant
variables. Table 6 presents the total contribution of surface Ta,
Pre, Win, Rn, and VPD to ET for LEDQTP using the SEM statistical
method across the entire TP and various land cover types. On the
whole TP, Ta has the strongest effect on ET with a standardized
estimate of 0.666, which is statistically significant at p < 0.005
(Table 6). The response mechanisms of ET to the influencing
factors resulting from the SEM are shown in Figure 6. It is
evident that Ta has a direct impact on ET as well as an indirect
influence through Ts leading to ET and Ts leading to NDVI, which
ultimately affects ET (Figure 6A). In other words, an increase in Ta
causes an increase in Ts, resulting in an increase in ET. Frontiers in Environmental Science frontiersin.org 3.3 Analysis of the influencing factors of the
ET changes Additionally, the increase in Ts leads to an increase in NDVI, which contributes to
the overall increase in ET. Teng et al. (2021) also found that the
increased ET on the TP was closely related to vegetation greening in
the past 30 years. Although the standardized estimate for Pre, which
is 0.403 and passes the significance test at p < 0.05, is lower than that
of Ta, it still has a direct impact on ET, as illustrated in Table 6
and Figure 6A. In the bare soil and grassland areas, the standardized estimates of
Ta and Pre both pass the significance test at p < 0.005, and Pre has the
higher values of 0.521 and 0.606, respectively (Table 6). This indicates
that both Ta and Pre have a significant effect on ET in the two land
cover type regions, and Pre has a stronger effect. Ma and Zhang (2022)
and He et al. (2019) also pointed out that the increased ET on the TP 08 frontiersin.org Li et al. 10.3389/fenvs.2024.1346469 FIGURE 5
Monthly ET (unit: mm) for GLEAM, LEDQTP, GLDAS, ERA5, and MERRA-2 corresponding to the observed latent heat flux at each observation site. (A) DX, (B) HBGCT1, (C) HBGCT2, (D) BJ, (E) QOMS, (F) SETORS, (G) MAWORS, (H) NADORS, (I) NAMORS. FIGURE 5 FIGURE 5
Monthly ET (unit: mm) for GLEAM, LEDQTP, GLDAS, ERA5, and MERRA-2 corresponding to the observed latent heat flux at each observation site. (A) DX, (B) HBGCT1, (C) HBGCT2, (D) BJ, (E) QOMS, (F) SETORS, (G) MAWORS, (H) NADORS, (I) NAMORS. TABLE 4 TCC between ET and observed latent heat flux at each observation site. TABLE 4 TCC between ET and observed latent heat flux at each observation site. DX
HBGCT1
HBGCT2
BJ
QOM
SETORS
MAWORS
NADORS
NAMORS
MEAN
GLEAM
0.874*
0.798*
0.929*
0.914*
0.799*
0.735*
0.722*
0.808*
0.600*
0.798*
LEDQTP
0.909*
0.794*
0.944*
0.924*
0.847*
0.677*
0.726*
0.756*
0.624*
0.800*
GLDAS
0.888*
0.686*
0.880*
0.907*
0.742*
0.763*
0.108
0.725*
0.654*
0.706*
ERA5
0.866*
0.757*
0.911*
0.928*
0.776*
0.701*
0.714*
0.793*
0.540*
0.776*
MERRA-2
0.871*
0.686*
0.905*
0.851*
0.817*
0.716*
0.577*
0.792*
0.656*
0.763*
Notes: * indicates correlation coefficients that pass the significance test at p < 0.001. affects ET. In bare soil areas, Ta affects ET through Ts (Figure 6B). The
increased Ta (Figure 7B) leads to an increase in Ts (Figure 7H), which
finally promotes an increase in ET. Frontiers in Environmental Science 3.3 Analysis of the influencing factors of the
ET changes In grassland areas, Ta (Figure 7B)
affects ET through Ts, which in turn affects NDVI and, ultimately, ET. In addition, the decrease in Rn (Figure 7E) contributes to the increase
in SM (Figure 7F), which finally contributes to the increase in ET. was primarily driven by the increased Pre, which was associated with
weakened westerlies that significantly correlated with the Atlantic
Multi-decadal Oscillation (AMO) on inter-decadal time scales (Sun
et al., 2020). As shown in Figures 6B and C, Pre affects ET primarily
through a direct pathway. The increase in Pre (Figure 7C) directly
contributes to the increase in ET (Figure 7A). However, Ta indirectly 09 frontiersin.org Li et al. 10.3389/fenvs.2024.1346469 TABLE 5 RSME between ET and observed latent heat flux at each observation site (unit: mm). DX
HBGCT1
HBGCT2
BJ
QOM
SETORS
MAWORS
NADORS
NAMORS
MEAN
GLEAM
27.502
39.254
26.348
33.446
15.932
24.776
39.910
16.143
30.025
28.148
LEDQTP
17.618
27.705
13.037
22.448
18.283
28.145
37.042
17.269
29.958
23.501
GLDAS
24.501
49.146
37.095
29.641
18.330
21.928
38.382
21.505
31.573
30.233
ERA5
22.470
34.484
20.907
22.891
19.795
26.380
29.822
14.062
34.354
25.018
MERRA-2
24.383
36.913
22.275
31.768
17.799
22.531
48.519
19.606
27.646
27.938 TABLE 6 Total contribution of Ta, Pre, Win, and Rn to ET estimated by SEM. TABLE 6 Total contribution of Ta, Pre, Win, and Rn to ET estimated by SEM. Ta~ET
Pre~ET
Win~ET
Rn~ET
Estimate
P
Estimate
P
Estimate
P
Estimate
P
All the TP
0.666**
0.000
0.403*
0.012
−0.121
0.448
0.010
0.955
Bare soil
0.385**
0.000
0.521**
0.000
−0.009
0.918
−0.168*
0.032
Grassland
0.529**
0.000
0.606**
0.000
−0.167
0.104
−0.023
0.811
Meadow
0.593**
0.000
0.286*
0.036
−0.636**
0.000
0.124
0.523
Shrub and forest
0.618**
0.000
0.025
0.743
−0.288**
0.000
0.393**
0.000
Sparse vegetation
0.699**
0.000
0.363*
0.007
0.054
0.627
0.027
0.813
Notes: * and ** indicate the contribution that pass the significance test at p < 0.05 and p < 0.005. would inhibit the increase in SM, but due to the more developed
root systems and the high water-holding capacity of the soil in forest
and shrub regions, the vegetation can still maintain SM even with a
decrease in Pre, which may be the reason why SM still increases in
these regions, but the trend is not as significant as in the other
areas (Figure 7F). Therefore, the total effect of Rn was insignificantly negative in the
two regions. 3.3 Analysis of the influencing factors of the
ET changes Different from the previous two regions, in the meadow and
shrub and forest regions, the total contributions of Ta to ET are the
largest, with standardized estimates of 0.593 and 0.618, respectively,
both passing the significance test at p < 0.005 (Table 6). Ta primarily
affects ET by an indirect pathway, mainly through VPD and Ts
(Figures 6D and E). It is worth noting that the standardized
estimates of Win are also significant at p < 0.05 in both regions
(Table 6). However, because Win presents a downward trend
(Figure 7D), it inhibits the increase of ET by reducing the
evaporation rate, with estimated values of −0.46 (Figure 6D)
and
−0.21
(Figure
6E). The
effect
of
Win
is
ultimately
outweighed by the positive contribution of Ta, so the ET still
presents an increasing trend (Figure 7A). In addition, it can be
seen that Pre has a larger negative effect on NDVI in meadow
regions (Figure 6D). Figure 7F shows that SM is already higher in the
meadow area, second only to the shrub and forest areas. Therefore,
the soil may be too wet due to higher Pre, causing plant roots to
receive excessive soaking, which can limit plant growth and
photosynthesis, ultimately reducing the NDVI. Previous studies
have also shown a negative relationship between Pre and
vegetation in other cold areas (Xu jie et al., 2019; Ma et al.,
2023). Furthermore, Pre over the TP falls in the form of snowfall
most of the time due to the special topography, and the snow cover
can hinder the identification of vegetation by satellite remote
sensing, which ultimately influences the NDVI. In the shrub and
forest regions, Pre has a negative direct contribution to ET
(Figure 6E). This is mainly because Pre in the shrub and forest
areas presents a decreasing trend (Figure 7C). In addition, Pre
indirectly affects ET through SM. Generally, a decrease in Pre Since sparse vegetation is scattered across the TP (Figure 1), the
total contribution of each influencing factor to ET is similar to that
of the whole TP, i.e., the contributions both of Pre and Ta to ET pass
the significance test at p < 0.05 and p < 0.005, respectively, but the
effect of Ta is relatively more significant with a standardized
estimate of 0.699 (Table 6). Ta primarily affects ET through a
direct pathway and secondarily by affecting Ts and then NDVI
indirectly. 3.3 Analysis of the influencing factors of the
ET changes Similarly, Rn also affects ET to some extent through
SM (Figure 6F). Summarily, ET shows an increasing trend averaged across the
TP and in all the land cover types. Both Ta and Pre have a significant
effect on the increased ET in the whole TP, bare soil, grassland, and
sparse vegetation regions. On the whole TP and sparse vegetation
region, the total contribution of Ta is more significant, while in the
bare soil and grassland regions, the contribution of Pre is more
significant. In the meadow as well as shrub and forest regions, Ta
plays a dominant role in the increase in ET. Frontiers in Environmental Science frontiersin.org Frontiers in Environmental Science 4 Discussion FIGURE 7
Inter-annual variations of (A) ET (mm), (B) Ta (°C), (C) Pre (mm), (D) Win (m s−1), (E) Rn (W m−2), (F) SM (mm), (G) NDVI, (H) Ts (°C), and (I) VPD (hPa)
averaged over different land cover types during 1982–2014. The datasets related to this study have been carefully selected
according to evaluations in previous studies so that they can more
accurately describe the climate changes over the TP. Nevertheless,
there are still some biases in these datasets compared to
observations, which could impact the results of this paper. For
example, GLDAS performed better in capturing the variations of in
situ SM and Ts, but it overestimated SM and showed lower Ts when
compared to the in situ measurements (Bi and Ma, 2015; Xu W. et al., 2019; Ma et al., 2021; Xing et al., 2021). Win in the CMFD had
the least bias with observations and could represent the variation of
observations well, but its correlation with the observations needed
improvement (Xie et al., 2017; He et al., 2020; Lin et al., 2023). For
Ta, although it was interpolated from observations and had high
accuracy, the gridded Ta was lower than the observation due to the
low altitude of the observing stations (Gao et al., 2015). the wet meadow and forest regions. This finding was in line with
previous studies that have indicated that ET was constrained by
moisture in arid regions and that the surface energy fluxes were
dominated by sensible heat fluxes. In contrast, in the humid
subsurface, ET was mainly limited by energy supply, with smaller
sensible heat fluxes, and the surface energy fluxes were dominated by
latent heat transfer (Taheri et al., 2022). The elevated CO2
concentration (Liu et al., 2021a), land use/land cover change
(LULCC) (Sterling et al., 2013; Li et al., 2017), and reservoir
storage (Scanlon et al., 2018) may also have larger impacts on ET
by changing the local water and energy balance. According to the
IPCC, global atmospheric CO2 concentrations have increased
(IPCC,
2013). An
increase
in
CO2
concentration
reduces
vegetation
stomatal
openness,
thereby
increasing
stomatal
resistance and reducing ET (Ainsworth and Long, 2005). Piao
et
al. (2012)
reported
that
the
rising
atmospheric
CO2
concentration was the main cause of vegetation increases in
eastern regions of the TP, and increased vegetation would lead to
increased ET. Frontiers in Environmental Science 4 Discussion This study evaluated five ET datasets using the observed latent
heat flux in order to investigate the main driving factors and
influencing mechanisms of ET over the TP in 1982–2014. However, the observations used in this paper are limited to only 10 frontiersin.org Li et al. Li et al. 10.3389/fenvs.2024.1346469 nine sites, which are sparsely located in the southern part of the TP
(Figure 1). Furthermore, the time series of observations from these
sites is too short, and the time duration is inconsistent for each
station (Table 2). It may not be adequate to evaluate the gridded data
solely based on these observations. Therefore, high-density and
long-time series of flux observations are urgently needed to
evaluate the available gridded datasets in order to obtain more
accurate ET data in future research. FIGURE 6
Results of the structural equation model for ET and its influencing factors over the whole TP (A) and different land cover types (B–F): (B) bare soil, (C)
grassland, (D) meadow, (E) shrub and forest, and (F) sparse vegetation. The numbers in the plots represent the fraction of variation explained for
dependent variables in the model. FIGURE 6
Results of the structural equation model for ET and its influencing factors over the whole TP (A) and different land cover types (B–F): (B) bare soil, (C)
grassland, (D) meadow, (E) shrub and forest, and (F) sparse vegetation. The numbers in the plots represent the fraction of variation explained for
dependent variables in the model. nine sites, which are sparsely located in the southern part of the TP
(Figure 1). Furthermore, the time series of observations from these
sites is too short, and the time duration is inconsistent for each
station (Table 2). It may not be adequate to evaluate the gridded data solely based on these observations. Therefore, high-density and
long-time series of flux observations are urgently needed to
evaluate the available gridded datasets in order to obtain more
accurate ET data in future research. 11 frontiersin.org Li et al. Li et al. 10.3389/fenvs.2024.1346469 FIGURE 7
Inter-annual variations of (A) ET (mm), (B) Ta (°C), (C) Pre (mm), (D) Win (m s−1), (E) Rn (W m−2), (F) SM (mm), (G) NDVI, (H) Ts (°C), and (I) VPD (hPa)
averaged over different land cover types during 1982–2014. frontiersin.org Funding The author(s) declare that financial support was received for the
research, authorship, and/or publication of this article. This work
was jointly supported by the Drought Meteorological Science
Research Foundation (IAM202216), the National Natural Science
Foundation of China (U20A2098, 42275092), and the open project
of Key Laboratory of Meteorological Disaster, Ministry of on
Forecast and Evaluation of Meteorological Disasters, Nanjing
University of Information Science and Technology (KLME202213). 1) ET over the TP decreases from the southeastern to the
northwestern regions. The maximum mean ET averaged
over the TP is 379.979 ± 0.417 mm a−1 for ERA5, and the
minimum is 249.899 ± 0.469 mm a−1 for GLDAS. In addition,
ET presents a clear seasonal cycle, with larger values mainly in
the summer. The differences among the datasets are more
pronounced in the summer. Although all five datasets show an
increasing trend in ET from 1982 to 2014, there are large
differences in the spatial distribution of the trend. 1) ET over the TP decreases from the southeastern to the
northwestern regions. The maximum mean ET averaged
over the TP is 379.979 ± 0.417 mm a−1 for ERA5, and the
minimum is 249.899 ± 0.469 mm a−1 for GLDAS. In addition,
ET presents a clear seasonal cycle, with larger values mainly in
the summer. The differences among the datasets are more
pronounced in the summer. Although all five datasets show an
increasing trend in ET from 1982 to 2014, there are large
differences in the spatial distribution of the trend. Acknowledgments The authors are grateful to the editor and the reviewers of
this paper. 2) The correlations between the five datasets and observations are
high, and the TCC between them passes the significance test at
p < 0.001 at almost all observation sites. LEDQTP possesses the
highest mean TCC of 0.800, while GLDAS has the lowest value
of 0.706. Additionally, LEDQTP has the minimum mean
RMSE of 23.501 mm, while GLDAS has the maximum
RMSE of 30.233 mm. Author contributions XL: conceptualization, data curation, formal analysis, funding
acquisition, methodology, software, writing–original draft, and
writing–review
and
editing. YP:
investigation,
supervision,
validation, and writing–review and editing. CZ: validation and
writing–review and editing. Conflict of interest The authors declare that the research was conducted in the
absence of any commercial or financial relationships that could be
construed as a potential conflict of interest. 3) Across the TP, Ta is the main influencing factor for ET. However, the main influencing factors of ET are different
in different land cover-type regions. In the wet meadow and
shrub and forest regions, Ta is the main and indirect
influencing factor, mainly through affecting VPD, with
standardized estimates of 0.593 and 0.618, respectively. Ta
is also the controlling factor in sparse vegetation regions, but it
affects ET through a direct pathway. However, in the dry, bare
soil and grassland regions, Pre is the main and direct
influencing factor, with standardized estimates of 0.521 and
0.606, respectively. Data availability statement discussed in the future. Li et al. (2017) pointed out that the
conversion of forest and wetland to other land uses caused a
decrease in ET, and the conversion of grassland to cropland
resulted in an increase in ET. Additionally, the LULCC would
also
affect
precipitation
(Zhang
and
Zhou,
2021)
and
air
temperature (Li et al., 2023), which in turn affected ET. The TP
was covered by a large amount of snow, glaciers, and permafrost
because of its unique terrain and climate features. Changes in the
cryosphere, such as snow reduction, glacial melting, and permafrost
degradation,
may
also
have
a
significant
impact
on
the
increase in ET. Publicly available datasets were analyzed in this study. These
data can be found here: the GLEAM dataset was downloaded
at https://www.gleam.eu/; the GLDAS dataset was downloaded at
https://disc.gsfc.nasa.gov/datasets?keywords=
the
ERA5
dataset was downloaded at https://www.ecmwf.int/en/forecasts/
datasets; the MERRA-2 dataset was downloaded at https://gmao. gsfc.nasa.gov/reanalysis/MERRA-2/;
the
China
Surface
Temperature/Precipitation 0.5° × 0.5° Grid Dataset (V2.0) was
downloaded at http://data.cma.cn/; the LEDQTP, CMFD, and
NDVI datasets were downloaded at http://data.tpdc.ac.cn; and
the observed latent heat flux datasets were downloaded at
https://www.scidb.cn/en/and http://www.nesdc.org.cn/. In addition to these local factors, larger-scale circulation patterns
may also play an important role in altering ET. Miralles et al. (2014)
reported that the dynamics of the El Niño/Southern Oscillation
(ENSO) have dominated the multi-decadal variability of ET at the
global scale. All these issues need to be further discussed in detail in
the future. 5 Summary and conclusion In this study, we analyzed the spatiotemporal characteristics of
ET over the TP in 1982–2014 based on multiple datasets and then
evaluated these datasets by comparing them with observations
from nine flux observation sites to select one that was closest to the
observation. Finally, based on the selected ET dataset, we
quantified the effect of each driving factor of ET and identified
the main influencing factors and their affecting pathways over the
different land surface types over the TP. The main conclusions are
as follows: 4 Discussion Therefore, the elevated CO2 concentration had
comprehensive impacts on ET, which needs to be further Due to the complexity of land–atmosphere interactions, ET is
influenced by various aspects. In this paper, we have only discussed
the influencing factors of ET from the perspective of climate change. The study found that Pre was the main influencing factor in dry,
bare soil and grassland areas, while Ta was the dominant factor in 12 frontiersin.org Li et al. Li et al. 10.3389/fenvs.2024.1346469 frontiersin.org Publisher’s note All claims expressed in this article are solely those of the authors
and
do
not
necessarily
represent
those
of
their
affiliated
organizations, or those of the publisher, the editors, and the
reviewers. Any product that may be evaluated in this article, or
claim that may be made by its manufacturer, is not guaranteed or
endorsed by the publisher. Frontiers in Environmental Science 13 frontiersin.org 10.3389/fenvs.2024.1346469 Li et al. References Ainsworth, E. A., and Long, S. P. (2005). What have we learned from 15 years of free-
air
CO2
enrichment
(FACE)? A
meta-analytic
review
of
the
responses
of
photosynthesis, canopy properties and plant production to rising CO2. New Phytol. 165, 351–372. doi:10.1111/j.1469-8137.2004.01224.x Lin, S., Wang, G., Hu, Z., Huang, K., Sun, X., Sun, J., et al. (2021). Dynamics of
evapotranspiration and variations in different land-cover regions over the Tibetan
plateau during 1961–2014. J. Hydrometeorol. 22, 955–969. doi:10.1175/jhm-d-20-
0074.1 Liu, J., You, Y., Li, J., Sitch, S., Gu, X., Nabel, J. E. M. S., et al. (2021a). Response of
global land evapotranspiration to climate change, elevated CO2, and land use change. Agric. For. Meteorol. 311, 108663. doi:10.1016/j.agrformet.2021.108663 Albergel, C., Dutra, E., Munier, S., Calvet, J.-C., Munoz-Sabater, J., Rosnay, P. de, et al. (2018). ERA-5 and ERA-Interim driven ISBA land surface model simulations: which one performs
better? Hydrol. Earth Syst. Sci. Discuss. 22, 3515–3532. doi:10.5194/hess-22-3515-2018 Allen, R. G., Pereira, L. S., Raes, D., and Smith, M. (1998). Crop evapotranspiration -
guidelines for computing crop water requirements - FAO Irrigation and drainage paper
56. Irrig. Drain., 1–15. doi:10.1016/j.eja.2010.12.001 Liu, J., Zhang, J., Kong, D., Feng, X., Feng, S., and Xiao, M. (2021b). Contributions
of anthropogenic forcings to evapotranspiration changes over 1980–2020 using
GLEAM and CMIP6 simulations. J. Geophys. Res. Atmos. 126, 1–14. doi:10.1029/
2021JD035367 Bai, P., and Liu, X. (2018). Intercomparison and evaluation of three global high-
resolution evapotranspiration products across China. J. Hydrol. 566, 743–755. doi:10. 1016/j.jhydrol.2018.09.065 López, O., Houborg, R., and McCabe, M. F. (2017). Evaluating the hydrological
consistency of evaporation products using satellite-based gravity and rainfall data. Hydrol. Earth Syst. Sci. 21, 323–343. doi:10.5194/hess-21-323-2017 Bi, H., and Ma, J. (2015). Evaluation of simulated soil moisture in GLDAS using in-
situ measurements over the Tibetan Plateau. IEEE Int. Symp. Geosci. Remote Sens.,
4825–4828. doi:10.1109/IGARSS.2015.7326910 Lu, J., Wang, G., Chen, T., Li, S., Hagan, D. F. T., Kattel, G., et al. (2021). A
harmonized global land evaporation dataset from model-based products covering 1980-
2017. Earth Syst. Sci. Data 13, 5879–5898. doi:10.5194/essd-13-5879-2021 Bosilovich, M., Akella, S., Coy, L., Cullather, R., Draper, C., Gelaro, R., et al. (2015). MERRA-2: initial evaluation of the climate. NASA Tech. Rep. Ser. Glob. Model. Data Assim. 43, 139. Ma, D., Wu, X., Yin, G., Li, Z., Wang, J., Tang, R., et al. (2023). References Enhanced latent heating over the
Tibetan Plateau as a key to the enhanced East asian summer monsoon circulation under
a warming climate. J. Clim. 32, 3373–3388. doi:10.1175/JCLI-D-18-0427.1 Martens, B., Schumacher, D. L., Wouters, H., Muñoz-Sabater, J., Verhoest, N. E. C.,
and Miralles, D. G. (2020). Evaluating the land-surface energy partitioning in ERA5. Geosci. Model Dev. 13, 4159–4181. doi:10.5194/gmd-13-4159-2020 He, J., Yang, K., Tang, W., Lu, H., Qin, J., Chen, Y., et al. (2020). The first high-
resolution meteorological forcing dataset for land process studies over China. Sci. Data
7, 25–11. doi:10.1038/s41597-020-0369-y Miralles, D. G., Holmes, T. R. H., De Jeu, R. A. M., Gash, J. H., Meesters, A. G. C. A.,
and Dolman, A. J. (2011). Global land-surface evaporation estimated from satellite-
based observations. Hydrol. Earth Syst. Sci. 15, 453–469. doi:10.5194/hess-15-453-2011 Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz-Sabater, J.,
et al. (2020). The ERA5 global reanalysis. Q. J. R. Meteorol. Soc. 146, 1999–2049. doi:10. 1002/qj.3803 Miralles, D. G., Van Den Berg, M. J., Gash, J. H., Parinussa, R. M., De Jeu, R. A. M.,
Beck, H. E., et al. (2014). El Niño-La Niña cycle and recent trends in continental
evaporation. Nat. Clim. Chang. 4, 122–126. doi:10.1038/nclimate2068 Immerzeel, W. W., Beek, L. P. H. van, and Bierkens, M. F. P. (2010). Climate change
will affect the asian water towers. Sci. 328, 5984. doi:10.1126/science.1183188 Ndehedehe, C. E., Okwuashi, O., Ferreira, V. G., and Agutu, N. O. (2018). Exploring
evapotranspiration dynamics over sub-sahara africa (2000–2014). Environ. Monit. Assess. 190, 400. doi:10.1007/s10661-018-6780-6 IPCC (2013). “Climate change 2013-the physical science basis,” in Working group I
contribution to the fifth assessment report of the intergovernmental panel on climate change
(Cambridge: Cambridge University Press). doi:10.1017/%0ACBO9781107415324 Pan, S., Pan, N., Tian, H., Friedlingstein, P., Sitch, S., Shi, H., et al. (2020). Evaluation
of global terrestrial evapotranspiration using state-of-the-art approaches in remote
sensing, machine learning and land surface modeling. Hydrol. Earth Syst. Sci. 24,
1485–1509. doi:10.5194/hess-24-1485-2020 Lal, P., Shekhar, A., Gharun, M., and Das, N. N. (2023). Spatiotemporal evolution of
global long-term patterns of soil moisture. Sci. Total Environ. 867, 161470. doi:10.1016/
j.scitotenv.2023.161470 Pan, Y., Li, X., Li, S., and Li, Z. (2022). Different responses of soil respiration to climate
change in permafrost and non-permafrost regions of the Tibetan plateau from 1979 to
2018. Int. J. Climatol. 42, 7198–7212. doi:10.1002/joc.7639 Li, G., Zhang, F., Jing, Y., Liu, Y., and Sun, G. (2017). References Detection, mapping,
and interpretation of the main drivers of the Arctic GPP change from 2001 to 2019. Clim. Dyn. 62, 723–738. doi:10.1007/s00382-023-06935-z Chen, X., Su, Z., Ma, Y., Trigo, I., and Gentine, P. (2021). Remote sensing of global
daily evapotranspiration based on a surface energy balance method and reanalysis data. J. Geophys. Res. Atmos. 126, 1–22. doi:10.1029/2020JD032873 Ma, H., Zeng, J., Zhang, X., Fu, P., Zheng, D., Wigneron, J. P., et al. (2021). Evaluation
of six satellite- and model-based surface soil temperature datasets using global ground-
based observations. Remote Sens. Environ. 264, 112605. doi:10.1016/j.rse.2021.112605 Chen, Y., Yang, K., He, J., Qin, J., Shi, J., Du, J., et al. (2011). Improving land surface
temperature modeling for dry land of China. J. Geophys. Res. Atmos. 116,
D20104–D20115. doi:10.1029/2011JD015921 Ma, N., Szilagyi, J., Zhang, Y., and Liu, W. (2019). Complementary-relationship-based
modeling of terrestrial evapotranspiration across China during 1982–2012: validations
and spatiotemporal analyses. J. Geophys. Res. Atmos. 124, 4326–4351. doi:10.1029/
2018JD029850 Cui, M., Wang, J., Wang, S., Yan, H., and Li, Y. (2019). Temporal and spatial distribution
of evapotranspiration and its influencing factors on Qinghai-Tibet Plateau from 1982 to
2014. J. Resour. Ecol. 10, 213–224. doi:10.5814/j.issn.1674-764X.2019.02.012 Ma,
N.,
and
Zhang,
Y. (2022). Increasing
Tibetan
Plateau
terrestrial
evapotranspiration primarily driven by precipitation. Agric. For. Meteorol. 317,
108887. doi:10.1016/j.agrformet.2022.108887 Gao, Y., Li, X., Ruby Leung, L., Chen, D., and Xu, J. (2015). Aridity changes in the
Tibetan Plateau in a warming climate. Environ. Res. Lett. 10, 034013. doi:10.1088/1748-
9326/10/3/034013 Ma, Y., Hu, Z., Xie, Z., Ma, W., Wang, B., Chen, X., et al. (2020). A long-term
(2005–2016) dataset of hourly integrated land–atmosphere interaction observations on
the Tibetan Plateau. Earth Syst. Sci. Data 12, 2937–2957. doi:10.5194/essd-12-2937-
2020 Gelaro, R., McCarty, W., Suárez, M. J., Todling, R., Molod, A., Takacs, L., et al. (2017). The modern-era retrospective analysis for research and applications, version 2
(MERRA-2). J. Clim. 30, 5419–5454. doi:10.1175/JCLI-D-16-0758.1 Martens, B., Miralles, D. G., Lievens, H., Van Der Schalie, R., De Jeu, R. A. M.,
Fernández-Prieto, D., et al. (2017). GLEAM v3: satellite-based land evaporation and
root-zone soil moisture. Geosci. Model Dev. 10, 1903–1925. doi:10.5194/gmd-10-1903-
2017 Han, C., Ma, Y., Wang, B., Zhong, L., Ma, W., Chen, X., et al. (2021). Long-term
variations in actual evapotranspiration over the Tibetan Plateau. Earth Syst. Sci. Data
13, 3513–3524. doi:10.5194/essd-13-3513-2021 He, C., Wang, Z., Zhou, T., and Li, T. (2019). References Spatial–temporal characteristics of precipitation and
its relationship with land use/cover change on the qinghai-tibet plateau, China. Land 10,
269. doi:10.3390/land10030269 Wang, T., Zhao, Y., Xu, C., Ciais, P., Liu, D., Yang, H., et al. (2021a). Atmospheric
dynamic constraints on Tibetan Plateau freshwater under Paris climate targets. Nat. Clim. Chang. 11, 219–225. doi:10.1038/s41558-020-00974-8 Zhang, H., Sun, J., and Xiong, J. (2017). Spatial-temporal patterns and controls of
evapotranspiration across the Tibetan plateau (2000-2012). Adv. Meteorol. 2017, 1–12. doi:10.1155/2017/7082606 Wang, Z., Zhan, C., Ning, L., and Guo, H. (2021b). Evaluation of global terrestrial
evapotranspiration in CMIP6 models. Theor. Appl. Climatol. 143, 521–531. doi:10.1007/
s00704-020-03437-4 Zhang, H., Wang, S., Ye, C., and Wang, Y. (2022). Trends and attribution analysis of
modelled evapotranspiration on the Tibetan Plateau. Hydrol. Process. 36. doi:10.1002/
hyp.14527 Xie, Z., Hu, Z., Gu, L., Sun, G., Du, Y., and Yan, X. (2017). Meteorological forcing
datasets for blowing snow modeling on the Tibetan Plateau: evaluation and
intercomparison. J. Hydrometeorol. 18, 2761–2780. doi:10.1175/JHM-D-17-0075.1 Zhang, T., Gebremichael, M., Meng, X., Wen, J., Iqbal, M., Jia, D., et al. (2018). Climate-related trends of actual evapotranspiration over the Tibetan Plateau
(1961–2010). Int. J. Climatol. 38. doi:10.1002/joc.5350 Xing, Z., Fan, L., Zhao, L., De Lannoy, G., Frappart, F., Peng, J., et al. (2021). A first
assessment of satellite and reanalysis estimates of surface and root-zone soil moisture
over the permafrost region of Qinghai-Tibet Plateau. Remote Sens. Environ. 265,
112666. doi:10.1016/j.rse.2021.112666 Zhang, Y., Peña-Arancibia, J. L., McVicar, T. R., Chiew, F. H. S., Vaze, J., Liu, C., et al. (2016). Multi-decadal
trends
in
global
terrestrial
evapotranspiration
and
its
components. Sci. Rep. 6, 19124–19212. doi:10.1038/srep19124 Xu, H. jie, Zhao, C. yan, and Wang, X. ping (2019a). Spatiotemporal differentiation of
the terrestrial gross primary production response to climate constraints in a dryland
mountain ecosystem of northwestern China. Agric. For. Meteorol. 276–277, 107628. doi:10.1016/j.agrformet.2019.107628 Zhang, Z., and Wang, K. (2020). Stilling and recovery of the surface wind speed based
on observation, reanalysis, and geostrophic wind theory over China from 1960 to 2017. J. Clim. 33, 3989–4008. doi:10.1175/JCLI-D-19-0281.1 Zhao, J., Ding, Y., and Yang, J. (2021). Suitability analysis and evaluation of GIMMS
NDVI3gProduct in plateau region. IOP Conf. Ser. Earth Environ. Sci. 734, 012007–7. doi:10.1088/1755-1315/734/1/012007 Xu, W., Sun, C., Zuo, J., Ma, Z., Li, W., and Yang, S. (2019b). Homogenization of
monthly ground surface temperature in China during 1961-2016 and performances of
GLDAS reanalysis products. J. Clim. 32, 1121–1135. References 3, 385–390. doi:10.1038/nclimate1690 Sun, J., Yang, K., Guo, W., Wang, Y., He, J., and Lu, H. (2020). Why has the inner
Tibetan plateau become wetter since the Mid-1990s? J. Clim. 33, 8507–8522. doi:10. 1175/JCLI-D-19-0471.1 Yang, Z., Yue, P., Zhang, Y., Zhang, Q., Zhang, L., Zeng, J., et al. (2022). Temporal
variability of evapotranspiration and its response to westerly and monsoon circulation
over the Tibetan Plateau. Theor. Appl. Climatol. 150, 1111–1129. doi:10.1007/s00704-
022-04202-5 Sun, S., Chen, B., Shao, Q., Chen, J., Liu, J., Zhang, X. jun, et al. (2017). Modeling
evapotranspiration over China’s landmass from 1979 to 2012 using multiple land
surface models: evaluations and analyses. J. Hydrometeorol. 18, 1185–1203. doi:10.1175/
JHM-D-16-0212.1 Yao, T., Thompson, L., Yang, W., Yu, W., Gao, Y., Guo, X., et al. (2012). Different
glacier status with atmospheric circulations in Tibetan Plateau and surroundings. Nat. Clim. Chang. 2, 663–667. doi:10.1038/nclimate1580 Taheri, M., Mohammadian, A., Ganji, F., Bigdeli, M., and Nasseri, M. (2022). Energy-
based approaches in estimating actual evapotranspiration focusing on land surface
temperature: a review of methods, concepts, and challenges. Energies 15, 1264. doi:10. 3390/en15041264 Yao, T., Xue, Y., Chen, D., Chen, F., Thompson, L., Cui, P., et al. (2019). Recent third
pole’s rapid warming accompanies cryospheric melt and water cycle intensification and
interactions between monsoon and environment: multidisciplinary approach with
observations, modeling, and analysis. Bull. Am. Meteorol. Soc. 100, 423–444. doi:10. 1175/BAMS-D-17-0057.1 Teng, H., Luo, Z., Chang, J., Shi, Z., Chen, S., Zhou, Y., et al. (2021). Climate change-
induced greening on the Tibetan Plateau modulated by mountainous characteristics. Environ. Res. Lett. 16, 064064. doi:10.1088/1748-9326/abfeeb Yin, Y., Wu, S., Zhao, D., Zheng, D., and Pan, T. (2013). Modeled effects of climate
change on actual evapotranspiration in different eco-geographical regions in the
Tibetan Plateau. J. Geogr. Sci. 23, 195–207. doi:10.1007/s11442-013-1003-0 Wang, G., Lin, S., Hu, Z., Lu, Y., Sun, X., and Huang, K. (2020a). Improving actual
evapotranspiration estimation integrating energy consumption for ice phase change across
the Tibetan plateau. J. Geophys. Res. Atmos. 125, 1–13. doi:10.1029/2019JD031799 Yu, G. R., Wen, X. F., Sun, X. M., Tanner, B. D., Lee, X., and Chen, J. Y. (2006). Overview of ChinaFLUX and evaluation of its eddy covariance measurement. Agric. For. Meteorol. 137, 125–137. doi:10.1016/j.agrformet.2006.02.011 Wang, K., Zhang, Y., Ma, N., Guo, Y., and Qiang, Y. (2020b). Cryosphere
evapotranspiration in the Tibetan Plateau: a review. Sci. Cold Arid. Reg. 12,
355–370. doi:10.3724/SP.J.1226.2020.00355 Zhang, B., and Zhou, W. (2021). References Response of evapotranspiration
to changes in land use and land cover and climate in China during 2001–2013. Sci. Total
Environ. 596–597, 256–265. doi:10.1016/j.scitotenv.2017.04.080 Piao, S., Tan, K., Nan, H., Ciais, P., Fang, J., Wang, T., et al. (2012). Impacts of climate
and CO 2 changes on the vegetation growth and carbon balance of Qinghai-Tibetan
grasslands over the past five decades. Glob. Planet. 99, 73–80. doi:10.1016/j.gloplacha. 2012.08.009 Li, R., Gao, Y., Chen, D., Zhang, Y., and Li, S. (2018a). Contrasting vegetation changes
in dry and humid regions of the Tibetan Plateau over recent decades. Sci. Cold Arid. Reg. 10, 482–492. doi:10.3724/SP.J.1226.2018.00482 Li, X., Chen, H., Hua, W., Ma, H., Li, X., Sun, S., et al. (2023). Modeling the effects of
realistic land cover changes on land surface temperatures over China. Clim. Dyn. 61,
1451–1474. doi:10.1007/s00382-022-06635-0 Pinzon, J. E., and Tucker, C. J. (2014). A non-stationary 1981-2012 AVHRR NDVI3g
time series. Remote Sens. 6, 6929–6960. doi:10.3390/rs6086929 Rodell, M., Houser, P. R., Jambor, U., Gottschalck, J., Mitchell, K., Meng, C. J., et al. (2004). The global land data assimilation system. Bull. Am. Meteorol. Soc. 85, 381–394. doi:10.1175/BAMS-85-3-381 Li, X., Gao, Y., Pan, Y., and Xu, Y. (2018b). Evaluation of near-surface wind speed
simulations over the Tibetan Plateau from three dynamical downscalings based on WRF
model. Theor. Appl. Climatol. 134, 1399–1411. doi:10.1007/s00704-017-2353-9 Scanlon, B. R., Zhang, Z., Save, H., Sun, A. Y., Schmied, H. M., Van Beek, L. P. H., et al. (2018). Global models underestimate large decadal declining and rising water storage
trends relative to GRACE satellite data. Proc. Natl. Acad. Sci. U. S. A. 115, E1080–E1089. doi:10.1073/pnas.1704665115 Lian, X., Piao, S., Huntingford, C., Li, Y., Zeng, Z., Wang, X., et al. (2018). Partitioning
global land evapotranspiration using CMIP5 models constrained by observations. Nat. Clim. Chang. 8, 640–646. doi:10.1038/s41558-018-0207-9 Lin, H., Yang, Y., Wang, S., Wang, S., Tang, J., and Dong, G. (2023). Evaluation of
MSWX bias-corrected meteorological forcing datasets in China. Sustain 15, 9283. doi:10.3390/su15129283 Song, L., Zhuang, Q., Yin, Y., Zhu, X., and Wu, S. (2017). Spatio-temporal dynamics of
evapotranspiration on the Tibetan Plateau from 2000 to 2010. Environ. Res. Lett. 12,
014011. doi:10.1088/1748-9326/aa527d Frontiers in Environmental Science 14 frontiersin.org 10.3389/fenvs.2024.1346469 Li et al. Li et al. areas of China. Hydrol. Earth Syst. Sci. 21, 5805–5821. doi:10.5194/hess-21-5805-
2017 Sterling, S. M., Ducharne, A., and Polcher, J. (2013). The impact of global land-cover change
on the terrestrial water cycle. Nat. Clim. Chang. References doi:10.1175/JCLI-D-18-0275.1 Zou, M., Zhong, L., Ma, Y., Hu, Y., and Feng, L. (2018). Estimation of actual
evapotranspiration in the Nagqu river basin of the Tibetan Plateau. Theor. Appl. Climatol. 132, 1039–1047. doi:10.1007/s00704-017-2154-1 Yang, F., Lu, H., Yang, K., He, J., Wang, W., Wright, J. S., et al. (2017). Evaluation of
multiple forcing data sets for precipitation and shortwave radiation over major land frontiersin.org 15 Frontiers in Environmental Science Frontiers in Environmental Science
|
https://openalex.org/W4312864685
|
https://mirtr.elpub.ru/jour/article/download/1141/3109
|
Russian
| null |
POLITICAL EDUCATION IN THE UNIVERSITY AS AN INCENTIVE FOR STUDENT CIVIC ENGAGEMENT
|
Mir transporta
| 2,017
|
cc-by
| 2,442
|
248
HRM, EDUCATION & TRAINING 248
HRM, EDUCATION & TRAINING ОБРАЗОВАНИЕ И КАДРЫ 248
HRM, EDUCATION & TRAINING УДК 378:32 Политическое образование
в вузе как стимул гражданской
активности студента Наталья ДЕНИСЕНКОВА
Natalia N. DENISENKOVA
Political Education in the University as an
Incentive for Student Civic Engagement
(текст статьи на англ. яз. –
English text of the article – p. 252) Наталья ДЕНИСЕНКОВА Наталья ДЕНИСЕНКОВА Денисенкова Наталья Николаевна – кандидат
политических наук, доцент Российского
экономического университета имени
Г. В. Плеханова (РЭУ), Москва, Россия. М М
одернизация политической жизни
России, становление правового
государства, многопартийности
и других демократических институтов вы
двинули перед высшей школой задачу об-
учения основам политологии студентов всех
специальностей, что призвано помочь как
политической социализации молодежи, так
и расширению кругозора специалистов,
которые смогут анализировать свои профес-
сиональные проблемы с учетом политиче-
ских концепций и методов. В процессе из-
учения политологии у студентов техниче-
ского вуза необходимо сформировать более
высокую политическую культуру, способ-
ность критически оценивать разнообразные
явления политической реальности, навыки
аналитического мышления, умение ориен-
тироваться в многообразии информации,
относящейся к общественной сфере. Political Education in the University as an
Incentive for Student Civic Engagement
(текст статьи на англ. яз. –
English text of the article – p. 252) Political Education in the University as an
Incentive for Student Civic Engagement
(текст статьи на англ. яз. –
English text of the article – p. 252) В большинстве своем исследованиями
отмечается низкая мотивация
к изучению политологии у студентов
негуманитарных специальностей. В статье приведены веские
доказательства важности
преподавания политологии
в техническом вузе. Показано, что
оно способствует формированию
гражданской активности будущих
специалистов. Утверждается, что
проблема гражданского образования
и воспитания современной российской
молодежи заслуживает постоянного
и пристального внимания, причем
на всех уровнях властной вертикали. И должна находить адекватное
отражение в учебном процессе любого
вуза, независимо от его отраслевой
принадлежности. Актуальным при этом является развитие
проблематики политического образования
для студентов транспортных вузов, особен-
но для специальностей и направлений,
обеспечивающих реализацию мультимо-
дальных межгосударственных логистиче-
ских цепочек. Сегодня любой вид транс-
порта может иметь выход на международ-
ный уровень, поэтому специалистам транс- Ключевые слова: высшее образование,
преподавание политологии, гражданская
активность, политическая социализация,
технический вуз. • МИР ТРАНСПОРТА, том 15, № 1, С. 248–253 (2017) • влиянию политологических концептов на
реальную практику управления [7–9]. портных отраслей нужны более полные
знания и четкие ориентиры в области
международной политики, гражданского
образования и в целом политической науки. Именно эти аспекты нашли свое отражение
в концепции развития транспортного обра-
зования до 2030 года и в проекте Российско-
го университета транспорта. портных отраслей нужны более полные
знания и четкие ориентиры в области
международной политики, гражданского
образования и в целом политической науки. Именно эти аспекты нашли свое отражение
в концепции развития транспортного обра-
зования до 2030 года и в проекте Российско-
го университета транспорта. В какой же мере оказались оправданными
эти ожидания и надежды? Наталья ДЕНИСЕНКОВА Очевидно, что
далеко не в полной мере. С тех пор, как в 1990
году Госкомитет по науке и технике СССР
принял решение о преподавании политоло-
гии и социологии в учебных заведениях
страны, сменилось несколько стратегий
власти. Становление политологии как самосто-
ятельной науки и учебной дисциплины на
Западе происходило в своеобразных исто-
рических условиях и определенном полити-
ческом контексте [1–4]. Вся история поли-
тической науки свидетельствует о том, что
для ее нормального развития необходимы,
по меньшей мере, два условия. Во-первых,
политология становится востребованной,
как правило, тогда, когда в обществе идут
процессы демократизации, которым она
сама в немалой степени способствует. Во-
вторых, польза для практики от политиче-
ской науки обычно прямо пропорциональ-
на ее независимости и неангажированно-
сти. Отсюда вывод: политология – это
сложная профессиональная сфера, которой
должны заниматься профессионально под-
готовленные люди [3–5]. На начальном этапе (первая половина
90-х годов прошлого века) отношения поли-
тической науки и власти можно было назвать
союзническими или, как минимум, партнер-
скими: власть, идентифицировавшая себя
в качестве демократической, воспринимала
теоретические постулаты, излагавшиеся
в соответствующих учебниках и монографи-
ях, как одобрение собственных намерений
и действий, их необходимую легитимацию. Однако по прошествии ряда лет, после
неудачного реформирования отечественной
экономики и социальной сферы, а также
вследствие болезненного раскола, возник-
шего в культурной области, отношение
к политическому знанию резко меняется
[8, 10]. Во второй половине 1990-х политическое
знание уже воспринимается как сугубо ин-
струментальное, где определяющую роль
выполняют политические технологи, обслу-
живающие интересы тех или иных политико-
финансовых группировок и игнорирующие
каноны моральной философии. Это стано-
вится не просто источником дохода (и нема-
лого), но и, к сожалению, нормой коммуни-
кативной культуры внутри значительной
части профессионального политологическо-
го сообщества [11, 12]. Как известно, введение политологии
в учебные планы вузов в России также про-
исходило в условиях демократизации совет-
ского, а затем и российского общества. Смена предельно идеологизированного
«научного коммунизма» современным по-
литическим знанием была призвана не
только сформировать у молодого поколения
россиян новую картину мира, но и воору-
жить молодежь жизненными ориентирами
в иной для них действительности практиче-
ской реализации [6–8]. Помимо прочего, на
политическую науку возлагались серьезные
надежды в плане научной экспертизы реше-
ний, принимавшихся новой властвующей
элитой, а также политической социализа-
ции молодого поколения на принципах
демократии, гражданской активности и т. д. Обе эти задачи вполне соответствовали Как известно, введение политологии
в учебные планы вузов в России также про-
исходило в условиях демократизации совет-
ского, а затем и российского общества. транспортном, состоит в том, что мотивация
к изучению политологии у студентов-негу-
манитариев явно снижена. ная роль политологии в политической социа
лизации состоит в формировании политиче-
ской грамотности и подлинной гражданст-
венности студенческой молодежи. ная роль политологии в политической социа
лизации состоит в формировании политиче-
ской грамотности и подлинной гражданст-
венности студенческой молодежи. Наталья ДЕНИСЕНКОВА Смена предельно идеологизированного
«научного коммунизма» современным по-
литическим знанием была призвана не
только сформировать у молодого поколения
россиян новую картину мира, но и воору-
жить молодежь жизненными ориентирами
в иной для них действительности практиче-
ской реализации [6–8]. Помимо прочего, на
политическую науку возлагались серьезные
надежды в плане научной экспертизы реше-
ний, принимавшихся новой властвующей
элитой, а также политической социализа-
ции молодого поколения на принципах
демократии, гражданской активности и т. д. Обе эти задачи вполне соответствовали
уровню требований, предъявляемых сегод-
ня к международному сообществу полито-
логов. Так, на Всемирном конгрессе Между-
народной ассоциации политической науки
в Дурбане (ЮАР, июнь-июль 2003 г.) особое
внимание было уделено проблемам разви-
тия политического сообщества и политиче-
ской науки в новых демократиях, а также Политическую социализацию можно
определить как процесс усвоения индивидом
идеологических и политических ценностей
и норм общества и формирование их в осоз-
нанную систему социально-политических
установок, определяющих позицию и пове-
дение индивида в политической системе
общества. Политически социализированный
человек не просто интересуется политикой
и участвует к ней. Обладая высоким полити-
ческим сознанием, политической культурой,
он действует в политической сфере в качест-
ве социально активной личности. Обе эти задачи вполне соответствовали
уровню требований, предъявляемых сегод-
ня к международному сообществу полито-
логов. Так, на Всемирном конгрессе Между-
народной ассоциации политической науки
в Дурбане (ЮАР, июнь-июль 2003 г.) особое
внимание было уделено проблемам разви-
тия политического сообщества и политиче-
ской науки в новых демократиях, а также 249
249 Главная сложность преподавания поли-
тологии в техническом вузе, в том числе • МИР ТРАНСПОРТА, том 15, № 1, С. 248–253 (2017) . Политическое образование в вузе как стимул гражданской активности студента транспортном, состоит в том, что мотивация
к изучению политологии у студентов-негу-
манитариев явно снижена. транспортном, состоит в том, что мотивация
к изучению политологии у студентов-негу-
манитариев явно снижена. Денисенкова Н. Н. Политическое образование в вузе как стимул гражданской активности студента ЛИТЕРАТУРА 1. Алмонд Г. Политическая наука: история дисци-
плины // В книге Политическая наука: новые направ-
ления / Под ред. Р. Гудина и Х.-Д. Клингеманна. – М.,
Вече, 1999. – 815 с. – С. 19–30. 1. Алмонд Г. Политическая наука: история дисци-
плины // В книге Политическая наука: новые направ-
ления / Под ред. Р. Гудина и Х.-Д. Клингеманна. – М.,
Вече, 1999. – 815 с. – С. 19–30. 2. Ануфриев Е. А. Политическая социализация
личности как проблема современной политологии
// Вестник Московского университета. Серия 18:
Социология и политология. – 1997. – № 4. – С. 34–44. Что же касается студентов, то осознание
ими своей невостребованности в собствен-
ной стране, подмена полноценной граж
данской активности манипулятивными
пиар-проектами (вроде «Наших», «Мест-
ных» и т. п.), перекрытие каналов восходя-
щей вертикальной мобильности на всех
уровнях властной пирамиды способны
радикализировать критический настрой
в их среде. Это может подтолкнуть отдель-
ных ее представителей к открытым про-
тестным действиям, подобным тем, кото-
рые предприняли в последние годы студен-
ты Сербии, Грузии или Украины, сыграв-
шие не последнюю роль в перенастройке
политики своих государств. Далеко не факт,
что подобная активность будет проявлять-
ся у нас в легальных, конвенциональных
формах. Помимо прочего, этим могут вос-
пользоваться политические силы, заинте-
ресованные в общей дестабилизации ситу-
ации в России. ц
3. Денисенкова Н. Н. Герменевтика современной
образовательной политики // Власть. – 2009. – № 1. –
С. 101–104. 3. Денисенкова Н. Н. Герменевтика современной
образовательной политики // Власть. – 2009. – № 1. –
С. 101–104. 4. Денисенкова Н. Н. Образовательная политика
России в современных условиях // Хозяйственные
системы в современном мире. Организационно-
управленческие институциональные аспекты: Моно-
графия / Под ред. Т. М. Степанян. – М.: Макс Пресс,
2009. – С. 298–304. 4. Денисенкова Н. Н. Образовательная политика
России в современных условиях // Хозяйственные
системы в современном мире. Организационно-
управленческие институциональные аспекты: Моно-
графия / Под ред. Т. М. Степанян. – М.: Макс Пресс,
2009. – С. 298–304. 5. Руденко Р. И. Традиционное и инновационное
в преподавании социологии и политологии // Вестник
Московского университета. Серия 18: Социология
и политология. – 1997. – № 3. – С. 156–167. 6. Соловьёв А. И. Теоретические приоритеты
российской политической науки в преподавании
// Политические исследования. – 2001. – № 5. –
С. 123–133. 7. Евстифеев Р. В. Политическое участие граждан
в формировании и развитии модели управления му-
ниципальным образованием // Ответственность
власти перед гражданским обществом: механизмы
контроля и взаимодействия. ная роль политологии в политической социа
лизации состоит в формировании политиче-
ской грамотности и подлинной гражданст-
венности студенческой молодежи. И с этой точки зрения нельзя
снижать и значимости целенаправленного
преподавания политических дисциплин
в высших учебных заведениях, где готовит-
ся не просто профессионал своего дела, но
и сознательный гражданин, патриот, сози-
датель будущего своей страны. ления, представителям власти решительнее
вступать в открытый диалог с молодыми
людьми. И с этой точки зрения нельзя
снижать и значимости целенаправленного
преподавания политических дисциплин
в высших учебных заведениях, где готовит-
ся не просто профессионал своего дела, но
и сознательный гражданин, патриот, сози-
датель будущего своей страны. предостережения о том, что надо бояться
отторжения новой официальной науки из-за
ее порой малой пригодности для объяснения
российской действительности. Политическая наука, чтобы сохранить
свою роль и предназначение в обществе,
должна стать критической теорией, нацелен-
ной на исследование возможности действия,
преодолевающего ту реальность, которая
утратила моральное измерение [5, 6, 9]. Если
этого не произойдет, она не только потеряет
свой нынешний статус в обществе, но и не-
избежно разделит судьбу прочих схоластиче-
ских теоретических построений типа науч-
ного коммунизма советских времен. Статья поступила в редакцию 02.11.2016, принята к публикации 17.01.2017. Координаты автора: Денисенкова Н. Н. – natalya652008@yandex.ru. ная роль политологии в политической социа
лизации состоит в формировании политиче-
ской грамотности и подлинной гражданст-
венности студенческой молодежи. Еще более существенным фактором,
осложняющим передачу научных достиже-
ний через преподавание в высшей школе,
является сам характер развития политиче-
ской науки. В преподавании политологии
всегда существует, с одной стороны, опас-
ность локализации политической проблема-
тики, редукции научных вопросов к страно-
вой специфике и как следствие – повышения
релятивности политических истин, а с дру-
гой – тенденция к излишней универсализа-
ции изучаемой тематики, что ведет к отрыву
учебного процесса от политической конкре-
тики. Для российских вузов в целом пред-
почтительнее всех учебная стратегия при
оритетного выбора сюжетов и предметных
областей, по преимуществу отображающих
специфику развития отечественной полити-
ки и вместе с тем отвечающих запросам
студенческой аудитории, но на основе ис-
пользования теоретического и практическо-
го инструментария, интегрирующего опыт
мирового знания. Есть основание надеяться, что гумани-
тарно-просветительского потенциал поли-
тологии, гражданское звучание научной
политической мысли обеспечат достойное
присутствие политических дисциплин в ин-
теллектуальном пространстве российской
высшей школы. Все неблагоприятные тенденции, кото-
рые формировались и обозначали себя в дис
курсивном поле политического знания, все
же не мешали ему выполнять роль опреде-
ленного нормативного ориентира для отно-
сительно слабого в России гражданского
общества, с трудом сохранявшего и поддер-
живавшего публичную политическую сферу. Почти пятнадцать лег заимствования и ос-
воения зарубежных разработок были одно
временно и временем, когда возникало по-
нимание того, что западные теории малопри-
годны для объяснения российских процес-
сов. Эти теории строились на ином
материале и объясняли реалии, характерные
дли иных политических и географических
ареалов. В отечественном контексте они
могут служить лишь подсказками и стиму-
лировать собственный поиск. Однако при-
знаем, что в столичных и провинциальных
центрах науки и образования зачастую ока-
зывалось престижнее, легче и материально
выгоднее пересказывать западные книги,
нежели биться над осмыслением живого
материала. Отсюда вполне уместно звучат Политология принадлежит к числу наук,
знакомство с которыми входит в необходи-
мый комплекс условий формирования лич-
ности. Преподавание профильных дисци-
плин этого ряда призвано помочь студентам
технического вуза рационально и критиче-
ски оценивать политические явления, созна-
тельно участвовать в политической жизни
страны, в частности, в выборах органов фе-
деральной и муниципальной власти. Основ- • МИР ТРАНСПОРТА, том 15, № 1, С. 248–253 (2017) • МИР ТРАНСПОРТА, том 15, № 1, С. 248–253 (2017) Политическое образование в вузе как стимул гражданской активности студента ления, представителям власти решительнее
вступать в открытый диалог с молодыми
людьми. ЛИТЕРАТУРА – М., 2014. – С. 184–189. 8. Старых Н. П. Социально-политическая актив-
ность граждан как фактор модернизации управления
муниципальным образованием // Модернизация
отечественной системы управления: анализ тенденций
и прогноз развития. – М., 2014. – С. 339–340. На наш взгляд, проблема гражданского
образования современной российской
молодежи заслуживает гораздо большего
внимания, причем на всех уровнях власт-
ной вертикали. Следует поощрять всесто-
роннюю просветительскую и воспитатель-
ную деятельность вузов, студенческих ор-
ганизаций и движений, политических
клубов молодежи, молодежных парламен-
тов, существующих в ряде регионов. Необ-
ходимо в меру разумного разблокировать
каналы восходящей вертикально мобиль-
ности для представителей молодого поко- 9. Королёва Л. В. Роль политического знания
в гуманитарном образовании студентов вузов // Ак-
туальные проблемы гуманитарных и естественных
наук. – 2012. – № 5. – С. 284–286. 10. Булычева С. Ф. Актуальность политического
образования в вузе // Научные труды SWorld. – 2008. –
№ 3. – С. 3–5. 11. Королёва Л. В. Некоторые современные про-
блемы политического образования студентов россий-
ских вузов // Социально-философские и социально-
экономические особенности развития образования
в столичном мегаполисе: Сборник научных статей /
Сост. Г. М. Гогиберидзе. – М., 2015. – С. 71–76. 12. Михайлова Н. В. Высшее образование в Рос-
сии: проблемы и перспективы // Российская наука
и образование сегодня: проблемы и перспективы. –
2016. – № 3. – С. 23–26. • 251 251 Координаты автора: Денисенкова Н. Н. – natalya652008@yandex.ru. • МИР ТРАНСПОРТА, том 15, № 1, С. 248–253 (2017) . Политическое образование в вузе как стимул гражданской активности студента
|
https://openalex.org/W4362416306
|
https://aacr.figshare.com/articles/journal_contribution/Supplementary_Figure_2_from_Efficacy_of_Levo-1-Methyl_Tryptophan_and_Dextro-1-Methyl_Tryptophan_in_Reversing_Indoleamine-2_3-Dioxygenase_Mediated_Arrest_of_T-Cell_Proliferation_in_Human_Epithelial_Ovarian_Cancer/22379111/1/files/39824474.pdf
|
unk
| null |
Supplementary Figure 2 from Efficacy of Levo-1-Methyl Tryptophan and Dextro-1-Methyl Tryptophan in Reversing Indoleamine-2,3-Dioxygenase–Mediated Arrest of T-Cell Proliferation in Human Epithelial Ovarian Cancer
| null | 2,023
|
cc-by
| 43
|
QIAN, et al. Supplemental Figure S2 QIAN, et al. Supplemental Figure S2 (-)
No MT D-1MT L-1MT No MT D-1MT L-1MT No MT D-1MT L-1MT
A
LIVE/DEAD Annexin V
PI
293 293IDO
No MT L-1-MT No MT L-1MT
(-)
B 293 B (-)
|
https://openalex.org/W4239910062
|
https://periodicos.ufmg.br/index.php/aletria/article/download/18041/14831
|
Portuguese
| null |
Quase pintura: poesia e visualidade em Pau Brasil, de Oswald de Andrade
|
Aletria
| 2,005
|
cc-by
| 5,991
|
QUASE PINTURA
poesia e visualidade em
poesia e visualidade em
poesia e visualidade em
poesia e visualidade em
poesia e visualidade em Pau-Brasil
Pau-Brasil
Pau-Brasil
Pau-Brasil
Pau-Brasil, de Oswald de Andrade
, de Oswald de Andrade
, de Oswald de Andrade
, de Oswald de Andrade
, de Oswald de Andrade Luciano Cortez
PucMinas 1 A primeira edição é de 1925, pela editora francesa Au Sans Pareil. Aqui utilizei a 4a. edição de
Poesias Reunidas (ANDRADE, O. de, 1974) e a Tese de Doutoramento de Diléa Zanotto Manfio,
Poesias Reunidas de Oswald de Andrade: edição crítica (MANFIO, 1992).
2 Movimento final das Bachianas Brasileiras no 2 para orquestra. RRRRR E S U M O
E S U M O
E S U M O
E S U M O
E S U M O A reconstituição dos dados da paisagem revelam os modos
operatórios do discurso poético de Oswald de Andrade para
traduzir o mundo em poesia. Essa tradução se fez por meio da
transposição de recursos de linguagem próprios às artes
plásticas das vanguardas européias de inícios do século XX
para o universo da palavra. Seu resultado foi uma poesia capaz
de reproduzir no plano verbal o dinamismo do mundo moderno. Em Oswald de Andrade isso implicou a elaboração de uma
poesia com sabor primitivista próximo ao que reconhecera na
pintura cubista. 2 Movimento final das Bachianas Brasileiras no 2 para orquestra. PPPPP A L A
A L A
A L A
A L A
A L A V R A S
V R A S
V R A S
V R A S
V R A S ----- C H A
C H A
C H A
C H A
C H A V E
V E
V E
V E
V E Em 1925 chegou da França o volume de poesias Pau-Brasil1, de Oswald de Andrade. Tratava-se de um livro ousado, já pela capa, que se podia ver completamente tomada pela
imagem produzida por Tarsila do Amaral. Ali inscrita, a palavra-título constituía parte
indissociável da expressão plástica produzida pela pintora: uma bandeira do Brasil posta na
vertical, com a divisa “PauBrasil” no lugar de “Ordem e Progresso”. A transformação, apesar
de simples, resultava em eficiente estranhamento. A mudança de orientação na disposição
da bandeira e a permuta do texto sobre a esfera, além da irreverência contida no gesto,
transformavam a imagem conhecida, a bandeira, em objeto com maior autonomia em relação
a seu referente imediato, porque evidenciavam a materialidade dos elementos próprios da
composição: o plano retangular, o losango, o círculo, o grafismo da palavra. Diria que a
imagem da bandeira se reconstruía, como combinação de planos geométricos parcialmente
abstratos, da mesma maneira que o ritmo de um trem de ferro correndo pelo sertão do
Brasil seria utilizado por Villa-Lobos, em 1930, como motivo recorrente na composição da
toccata “O trenzinho do caipira”2. Ou, ainda de outra forma, realizava ação próxima àquela 9 4 A L E T R I A - jan.-jun. - 2 0 0 6 Disponível em: http://www.letras.ufmg.br/poslit Disponível em: http://www.letras.ufmg.br/poslit da pintura européia, que desde o final do século XIX, a partir de Cézanne, afastara-se do
puro espelhamento dos objetos exteriores e assumira a reflexão sobre a organização do
espaço pictórico como uma tarefa própria dessa arte3. Nessa medida a capa sugeria ao
leitor, além de uma temática comum à época – a necessidade de construção de uma
identidade para o país –, um modo de operar essa representação. Ora, essa alternativa, quanto à forma esboçada pela capa, não era de maneira alguma
consensual. Contudo a temática nacionalista, sim. Há mais de um século os intelectuais
brasileiros se debatiam frente aos nossos problemas de identidade; a Semana de Arte
Moderna, em 1922, fora mais um momento nesse embate. As alternativas para o impasse
acabavam todas por testemunhar as dificuldades das elites culturais do país periférico, que
se encontravam comprimidas entre a necessidade de construção de uma imagem própria
para o Brasil e o fato de as linguagens e conceitos socialmente capazes de representá-lo
terem origem nos centros econômicos e culturais em relação aos quais se pretendia ganhar
autonomia. 3 O construtivismo lembrado na opção de Tarsila é possivelmente decorrente do formato da bandeira.
O início do século colocava à disposição dos artistas uma amplitude de possibilidades que permitiam
soluções como essa para o livro de Oswald. Contudo exemplos de bandeiras em pintura no início do
século XX ocorrem com estas incluídas numa paisagem, o que só demonstra a capacidade inventiva
da pintora. Elementos iconográficos populares também foram transformados por Malevitch: os
símbolos da tradição cristã-ortodoxa russa, como cruzes, serviram-lhe de padrão gráfico
(HARRISON, In: HARRISON, FRASCINA, PERRY, 1998). 3 O construtivismo lembrado na opção de Tarsila é possivelmente decorrente do formato da bandeira.
O início do século colocava à disposição dos artistas uma amplitude de possibilidades que permitiam
soluções como essa para o livro de Oswald. Contudo exemplos de bandeiras em pintura no início do
século XX ocorrem com estas incluídas numa paisagem, o que só demonstra a capacidade inventiva
da pintora. Elementos iconográficos populares também foram transformados por Malevitch: os
símbolos da tradição cristã-ortodoxa russa, como cruzes, serviram-lhe de padrão gráfico
(HARRISON, In: HARRISON, FRASCINA, PERRY, 1998).
4 ANDRADE, M. de, ANDRADE, Carlos Drummond de, 2002.
5 Schoenberg, em carta de 1945 a William S. Schlamm, afirmava: “Se é ARTE, não é para as
massas. E se é para as massas não é ARTE.” (LEIBOWITZ, 1981, p. 21). Disponível em: http://www.letras.ufmg.br/poslit 5 Schoenberg, em carta de 1945 a William S. Schlamm, afirmava: “Se é ARTE, não é para as
massas. E se é para as massas não é ARTE.” (LEIBOWITZ, 1981, p. 21). PPPPP A L A
A L A
A L A
A L A
A L A V R A S
V R A S
V R A S
V R A S
V R A S ----- C H A
C H A
C H A
C H A
C H A V E
V E
V E
V E
V E Como os projetos de independência cultural só existiam no mundo das idéias,
alienados que estavam das relações econômicas concretas que governavam as ações entre
os homens, o processo de produção de uma identidade para o país era de definição
necessariamente vaporosa, confusa, inconsistente. Observe-se, por exemplo, a carta de
Mário de Andrade a Drummond, de 1924, na qual afirmava que “Nacionalismo quer
simplesmente dizer: ser nacional”4, tautologia que buscava suprir deficiências de leitura do
quadro histórico. Menos ainda tem o poeta os meios de indicar exatamente como se
alcançaria isso. Não se imagine que esse desnorteio fosse exclusivo de Mário de Andrade; ele pode
ser visto também no “Manifesto da poesia Pau-Brasil”. Ali Oswald simplesmente
compreendia as sociedades, tanto a brasileira quanto as européias, divididas entre uma
elite, capacitada para a fruição estética, e os setores submetidos ao gosto discutível da
cultura de massas, de caráter pequeno-burguês, marcada pela banalização dos sentidos5. A solução oswaldiana para a questão nacional não estava demarcada por uma
necessidade de diferenciação completa da nossa cultura frente à européia, como entendia
Mário. Ele compreendia ser universal o movimento modernista, postulando o acompanhamento,
pela consciência nacional, do movimento de renovação por que passava o mundo. O contato com a Europa, por outro lado, colocou os modernistas que por lá passaram
frente a solicitações aparentemente contrárias ao mito da modernidade. Refiro-me ao
primitivismo das correntes de vanguarda européias, incorporado às obras desses grupos 9 5 2 0 0 6 - jan.-jun. - A L E T R I A Disponível em: http://www.letras.ufmg.br/poslit enquanto meio de ataque ao modo de vida burguês ou como repertório de formas de que
esses artistas poderiam se valer para a construção de uma expressão “livre” e “pura” do ser. A origem européia dessa valorização do primitivismo acabou, no entanto, por ser
utilizada como argumento contrário àqueles que o praticavam no Brasil. Daí a desconfiança
alardeada frente ao primitivismo de Oswald de Andrade, visto, segundo Tristão de Athayde,
“como fórmula pindorâmica de um anseio europeu, cuja degeneração foi expressa no
dadaísmo francês e no expressionismo alemão”6. E completava: O que pretendeu, portanto, o sr. Oswald de Andrade e o grupo de seus admiradores,
é abolir todo o esforço poético no sentido da lógica da beleza da construção e nadar
no instintivo, na bobagem, na mediocridade. Exaltar a vulgaridade. Chegar ao puro
balbuciamento infantil. PPPPP A L A
A L A
A L A
A L A
A L A V R A S
V R A S
V R A S
V R A S
V R A S ----- C H A
C H A
C H A
C H A
C H A V E
V E
V E
V E
V E Reproduzir a mentalidade do imbecil, do homem do povo ou
do almofadinha dos cafés. Curvar o joelho diante de todos os prosaísmos. Voltar ao
bárbaro ou deleitar-se no suburbano.7 Ou, numa reafirmação desse mesmo ponto de vista por Graça Aranha: Ou, numa reafirmação desse mesmo ponto de vista por Graça Aranha: Se escaparmos da cópia européia não devemos permanecer na incultura. Ser brasileiro
não significa ser bárbaro. Os escritores que no Brasil procuram dar de nossa vida a
impressão de selvageria, de embrutecimento, de paralisia espiritual, são pedantes
literários. Tomaram atitude sarcástica com a presunção de superioridade intelectual,
enquanto os verdadeiros primitivos são pobres de espírito, simples e bem-aventurados. O primitivismo dos intelectuais é um ato de vontade, um artifício como o arcadismo
dos acadêmicos. O homem culto de hoje não pode fazer tal retrocesso, como o que
perdeu a inocência não pode adquiri-la. Seria um exercício de falsa literatura naqueles
que pretendem suprimir a literatura. Ser brasileiro não é ser selvagem, ser humilde,
escravo do terror, balbuciar uma linguagem imbecil, rebuscar os motivos da poesia e
da literatura unicamente numa pretendida ingenuidade popular, turvada pelas
influências e deformações da tradição européia.8 Apesar da aversão dos dois leitores aos poemas de Pau-Brasil, constata-se nesses
excertos o quão bem compreendiam facetas essenciais da poesia oswaldiana: 1o) “a
reabilitação do nosso falar cotidiano”9, vista aqui como “artifício”, por Graça Aranha, como
“falsa literatura naqueles que pretendem suprimir a literatura”; 2o) o aproveitamento de
material não-literário, retirado da publicidade, de bilhetes de amor, do jornalismo da época,
compreendidos por Tristão de Athayde como “prosaísmos”, como abolição de “todo esforço
poético no sentido da lógica da beleza da construção”; 3o) a fragmentação do discurso
poético, recurso próprio do cinema e das artes plásticas de vanguarda, que Graça Aranha
enxergava como “deformações da tradição européia”. O que em Pau-Brasil para muitos sugeria um “esquema a ser desenvolvido” (Afonso
Arinos)10, poesia “tecnicamente mal construída” (Carlos Drummond de Andrade)11, “puro
balbuciamento infantil” (Tristão de Athayde)12, correspondia a virtudes centrais de Pau- 6 Apud BOAVENTURA, 1995, p. 114. 7 Apud BOAVENTURA, 1995, p. 114. 8 In: TELES, 1985, p. 322 e 323. 9 PRADO, In: ANDRADE, 1974, p. 69. 10 Afonso Arinos, apud BOAVENTURA, 1995, p. 112. 11 Carlos Drummond de Andrade, apud BOAVENTURA, 1995, p. 114. 12 Tristão de Athayde, apud BOAVENTURA, 1995, p. 114. 9 6 A L E T R I A - jan.-jun. 6 Apud BOAVENTURA, 1995, p. 114.
7 Apud BOAVENTURA, 1995, p. 114.
8 In: TELES, 1985, p. 322 e 323.
9 PRADO, In: ANDRADE, 1974, p. 69.
10 Afonso Arinos, apud BOAVENTURA, 1995, p. 112.
11 Carlos Drummond de Andrade, apud BOAVENTURA, 1995, p. 114.
12 Tristão de Athayde, apud BOAVENTURA, 1995, p. 114. Disponível em: http://www.letras.ufmg.br/poslit Disponível em: http://www.letras.ufmg.br/poslit PPPPP A L A
A L A
A L A
A L A
A L A V R A S
V R A S
V R A S
V R A S
V R A S ----- C H A
C H A
C H A
C H A
C H A V E
V E
V E
V E
V E - 2 0 0 6 Disponível em: http://www.letras.ufmg.br/poslit Disponível em: http://www.letras.ufmg.br/poslit Brasil, estratégias de ordenamento de vasto material coletado, transformado ou construído,
tendo o país como motivo. À primeira vista contraditórios nos poemas de Oswald de Andrade, o Brasil moderno
e seus resquícios coloniais ali conviviam como matéria a ser descrita de um ponto de vista
principalmente plástico. Há nessa poesia a recusa voluntária de uma pesquisa histórica
profunda e sistemática. O autor, segundo declaração própria, se contenta em “fixar com
simplicidade, sem comentários, sem erudição, sem reminiscência, os fatos poéticos de nossa
nacionalidade”13. Como em “primeiro chá”, retirado da Carta de Pero Vaz de Caminha. primeiro chá14 primeiro chá14 Depois de dançarem
Diogo Dias
Fez o salto real Depois de dançarem
Diogo Dias
Fez o salto real A respeito desse poema afirmava: Um crítico de tipo “profundo” poderia aí pesquisar a fundação da raça, a obra
civilizadora, que sei eu, partida dessa primeira reunião social dada no Brasil. Nesse
pulo de galego contente na praia das descobertas eu vejo poesia. E
b Um crítico de tipo “profundo” poderia aí pesquisar a fundação da raça, a obra
civilizadora, que sei eu, partida dessa primeira reunião social dada no Brasil. Nesse
pulo de galego contente na praia das descobertas eu vejo poesia. E poesia bem nossa. O estado de inocência que o espírito sorve nas notícias dos cronistas sobre ananases,
rios e riquezas e nos casos de negros fugidos e assombrações trazidos a nós pela tradição
oral e doméstica não é, porém, privilégio do passado. A mesma inspiração de poesia
anda aí nos jornais de hoje e nos fatos de nossa vida pessoal.15 p
O estado de inocência que o espírito sorve nas notícias dos cronistas sobre ananases,
rios e riquezas e nos casos de negros fugidos e assombrações trazidos a nós pela tradição
oral e doméstica não é, porém, privilégio do passado. A mesma inspiração de poesia
anda aí nos jornais de hoje e nos fatos de nossa vida pessoal.15 A atitude de Oswald, nessa declaração, poderia confundir-se com a de Manuel
Bandeira, que também fez “poema tirado de uma notícia de jornal”16. Segundo Davi
Arrigucci, esse poema foi “achado como um objet trouvé dos dadaístas, em meio à matéria
mais heterogênea e prosaica do cotidiano, de repente transformada em matéria literária”17. Porém há nessa afirmação um exagero, Bandeira nunca pretendeu escrever poesia dadaísta. Mais acertadamente, para Bandeira o jornal seria o meio cotidiano de onde se poderia
extrair poesia, isto é, o jornal seria a ganga, matéria bruta, que deveria ser transformada em
poesia pela ação do poeta. Oswald, ao contrário, simplesmente afirmava o universo cotidiano
como poético, sem recurso à manipulação desse material através de algum procedimento
que lhe concedesse sentido poético elevado, segundo entendimento tradicional. Em parte o que não agradava a Bandeira na poesia de Oswald era esse seu caráter
pouco “poético”. A poesia oswaldiana era demasiadamente chã e quase toda descarnada
de conflitos humanos fundamentais. Estaria mais próxima, talvez sem exagero, da pintura
de Matisse, “uma arte de equilíbrio, de pureza, de serenidade, desprovida de motivos
inquietadores ou deprimentes; uma arte que seja, para todo trabalhador cerebral, para o 13 ANDRADE, O. de, 1990, p. 25. 13 ANDRADE, O. de, 1990, p. 25.
14 ANDRADE, O. de, 1990, p. 23.
15 ANDRADE, O. de, 1990, p. 23.
16 BANDEIRA, 1970, p. 117.
17 ARRIGUCCI JÚNIOR, 1990, p. 91. A respeito desse poema afirmava: 14 ANDRADE, O. de, 1990, p. 23. 15 ANDRADE, O. de, 1990, p. 23. 16 BANDEIRA, 1970, p. 117. 17 ARRIGUCCI JÚNIOR, 1990, p. 91. 9 7 2 0 0 6 - jan.-jun. - A L E T R I A homem de negócios ou para o artista das letras, por exemplo, um lenitivo, um tranqüilizante
mental, semelhante a uma boa poltrona que o faz repousar de suas fadigas físicas”18. homem de negócios ou para o artista das letras, por exemplo, um lenitivo, um tranqüilizante
mental, semelhante a uma boa poltrona que o faz repousar de suas fadigas físicas”18. Essa aproximação talvez não seja abusiva, porque a poesia oswaldiana se viabilizaria
no olhar hedonista que expressa. Da paisagem – real, ficcional ou da publicidade – Oswald
captura o dado plástico, o salto inesperado na superfície histórica, e o materializa como
texto; procura “Substituir a perspectiva visual e naturalista por uma perspectiva de outra
ordem: sentimental, intelectual, ingênua.”19 Um exemplo dessa poesia rarefeita do cotidiano, produzida por Oswald de Andrade,
constituída por pequenos detalhes do mundo, pode ser encontrada em bucólica: bucólica20 Agora vamos correr o pomar antigo
Bicos aéreos de patos selvagens
Tetas verdes entre folhagens
E uma passarinhada nos vaia
Num tamarindo
Que decola para o anil
Árvores sentadas
Quitandas vivas de laranjas maduras
Vespas A poesia pastoril, em versão modernista, começa exatamente por dissolver o plano
narrativo, pela sua substituição por elementos da paisagem apresentada, dispersos nos versos
como dispersos na natureza. Outro recurso para a produção dessa nova perspectiva consistiria
em justapor, alternados, o amplo (“o pomar”, o “tamarindo” e as “árvores”) ao diminuto
(“bicos”, “tetas”, “folhas”, “laranjas”, “vespas”). O efeito alcançado é o mesmo originado
da ausência de proporções na arte popular, primitiva ou ingênua, ou no cubismo sintético
com seu ajuste de elementos díspares na superfície da tela, ou seja, uma percepção sensualista
do espaço, aqui reforçada pela carga erótica de parte do material discursivo apresentado:
“bicos”, “tetas verdes entre folhas”, “árvores sentadas”, “quitandas vivas de laranjas
maduras”, “vespas”. Uma certa reapresentação do mundo quase física aos nossos olhos e
sentidos todos. A estesia em Oswald de Andrade, portanto, ocorreria através dessas sugestões visuais,
formadas pelos fragmentos de mundo nomeados e justapostos, de forma a requisitar do
leitor procedimento próximo à percepção de uma pintura moderna, cujas partes seriam
articuladas por seu olhar, guardando cada uma, no entanto, a densidade de sua própria
significação. Disponível em: http://www.letras.ufmg.br/poslit 18 MATISSE, In: CHIPP, 1993, p. 131 e 132.
19 ANDRADE, O. de, In: TELES, 1985, p. 329
20 ANDRADE, O. de, 1974, p. 99. A respeito desse poema afirmava: Em outras palavras, as relações entre esses versos corresponderiam às que
existiriam, numa colagem, entre o material colado e o todo do quadro. Esses fragmentos
afixados na pintura em parte se dissolveriam no plano, como textura, linha e cor, ao mesmo
tempo que guardariam, por sua presença, uma memória do objeto total que antes
representavam ou constituíam. 18 MATISSE, In: CHIPP, 1993, p. 131 e 132. 19 ANDRADE, O. de, In: TELES, 1985, p. 329
20 ANDRADE, O. de, 1974, p. 99. 9 8 A L E T R I A - jan.-jun. - 2 0 0 6 Disponível em: http://www.letras.ufmg.br/poslit Oswald de Andrade procurou assim conferir unidade discursiva ao livro-objeto Pau-
Brasil pela eleição, enquanto modelos, dos textos dos cronistas estrangeiros que por aqui
passaram. Destes textos foram retiradas pequenas parcelas, matéria para colagem, que por
seu aspecto de apontamento e suas qualidades visuais aproximavam-se da incompletude,
do aspecto ligeiro dos estudos de viagem de Tarsila do Amaral naquele período. Na primeira parte do livro, em “História do Brasil” e “Poemas da Colonização”, temos
o passado remoto ou próximo tornado visível a partir de sua captura das fontes escritas e
orais de nossa tradição. Em “São Martinho” e partes seguintes, os poemas foram construídos
com os recursos vistos em “bucólica”. Também eles se conformam como apontamentos de
um percurso, mas que se dá no presente – presente do artista moderno, que se anunciava
como divulgador imprescindível de uma nova ordem fundada nos “ritmos renovados sem
cessar”, no “nomadismo épico”, no “exploratismo urbano”, na “Arte das viagens e dos
passeios”, como queria Apollinaire21. Outro exemplo dessa abordagem plástica oswaldiana, entre muitos outros, que
poderíamos recolher de Pau-Brasil, é o poema “aproximação da capital”, contido em “Roteiro
das Minas”, segmento que reconstrói a viagem dos modernistas a Minas Gerais, em 1924. 21 APOLLINAIRE, In: TELES, 1985, p. 118, 121.
22 ANDRADE, O. de, 1925, p. 95. As edições posteriores incorporam os três últimos versos à
estrofe anterior. Achamos que essa modificação tornou mais abrupta a aparição dos impermeáveis,
borzeguins e pijamas, produzindo efeito mais espetacular do que seu isolamento em estrofe própria,
como na edição de 1925. Disponível em: http://www.letras.ufmg.br/poslit 21 APOLLINAIRE, In: TELES, 1985, p. 118, 121. A respeito desse poema afirmava: Trazem-nos poemas no trem
Azuis e vermelhos
Como a terra e o horizonte
É um hotel rigorosamente familiar
Que oferece vantagens reais
Aos dignos forasteiros
Havendo o máximo escrúpulo na direção da cozinha Trazem-nos poemas no trem
Azuis e vermelhos
Como a terra e o horizonte
É um hotel rigorosamente familiar
Que oferece vantagens reais
Aos dignos forasteiros
Havendo o máximo escrúpulo na direção da cozinha Casas defendem o vosso próprio interesse
Proporcionando-vos uma economia
De 2$000, de 3$000 Impermeáveis
Borzeguins
Pijamas22 O poema retrata a transição do meio rural ao urbano, o que já estava indicado em
seu próprio título. Os “Azuis e vermelhos” trazidos ao trem são “Como a terra e o horizonte”,
também eles em vermelhos e azuis. Mas os objetos que comportam essas novas cores não se
confundem com a paisagem natural, são apenas “como” a natureza. Em outro poema, “capela nova”, 9 9 2 0 0 6 - jan.-jun. - A L E T R I A Salão Mocidade
Hotel do Chico
Uma igreja velha e cor-de-rosa
Na decoração dos bananais
Dos coqueirais23 os implementos urbanos presentes nos três primeiros versos dissolvem-se “Na decoração
dos bananais / Dos coqueirais”, ao passo que, em “aproximação da capital”, é a natureza que
se dissipa no pregão publicitário, nas placas comerciais e no mostruário das lojas, indiciando
a aproximação de Belo Horizonte. Neste poema, a aparição dos termos da paisagem, agora
urbanizada, é abrupta, devido à ruptura entre o terceiro e quarto versos da primeira estrofe,
assim como aquela entre a segunda e a terceira estrofe. Temos, então, uma estrutura de
quatro partes: 1. Trazem-nos poemas no trem
Azuis e vermelhos
Como a terra e o horizonte 2. É um hotel rigorosamente familiar
Que oferece vantagens reais
Aos dignos forasteiros
Havendo o máximo de escrúpulo na direção da cozinha 3. Casas defendem o vosso próprio interesse
Proporcionando-vos uma economia
De 2$000, de 3$000 4. Impermeáveis
Borzeguins
Pijamas 4. Impermeáveis
Borzeguins
Pijamas É evidente que os três primeiros versos regem todos os outros, pois esses “Azuis e
vermelhos”, plásticos por excelência, são poemas. Isto é, “aproximação da capital” busca
evidenciar, como apontado no “Manifesto da poesia pau-brasil”, que “A poesia existe nos
fatos”. 23 ANDRADE, O. de, 1925, p. 93. Disponível em: http://www.letras.ufmg.br/poslit A respeito desse poema afirmava: Em outras palavras, busca evidenciar que aspectos da paisagem brasileira urbana,
assim como a rural, possuem plasticidade suficiente para sua elevação à condição de objetos
estéticos, desde que isolados do contínuo de sua ambiência original, seja fisicamente, seja
virtualmente através do olhar que recorta. Por isso “aproximação da capital” pode-se referir,
por meio da linguagem verbal, a essa expressividade da paisagem. É em virtude desses três primeiros versos que poderemos entender o segmento
seguinte, o restante da estrofe, como exemplo desse tipo de “poema” a que o início do texto
alude. Ainda referente a essa proposição, soma-se, na estrofe seguinte, novo exemplo dessa
poesia conquistada à paisagem. Ela vem acompanhada por um detalhamento, a apresentação
de produtos disponíveis nessas casas comerciais, evidenciados na terceira estrofe:
“Impermeáveis / Borzeguins / Pijamas”. Assim esses quatro segmentos estão ordenados dois
a dois: o segundo segmento servindo como exemplo do que é proposto no início do poema;
e o quarto funcionando como detalhamento ou materialização dos produtos das casas 100 A L E T R I A - jan.-jun. - 2 0 0 6 Disponível em: http://www.letras.ufmg.br/poslit comerciais citadas no terceiro segmento. Afora isso, a segunda e a terceira estrofes servem
como exemplos adicionais à proposição inicial de “aproximação da capital”. O índice dessa proximidade da grande cidade é o surgimento, na paisagem, dos sinais
de serviços ou do comércio próprios aos centros urbanos, mesmo que simplificados no
“hotel rigorosamente familiar” ou em prosaicos “Impermeáveis / Borzeguins / Pijamas”,
anunciados nas casas comerciais modestas da periferia da capital. O gênero discursivo que permite nosso contato com essas pequenas empresas é a
publicidade, na forma do anúncio em “Azuis e vermelhos”, ou como mostruário de porta de
loja, a referência aos “Impermeáveis / Borzeguins / Pijamas” que dão fecho ao poema. Em
“aproximação da capital” a publicidade diluída na paisagem é condensada em um novo texto,
que pretende simular aquele e ao mesmo tempo situar o leitor no espaço que procura
instaurar. O surgimento repentino das referências ao hotel familiar, desconectado formalmente
dos três versos iniciais, reforça a sensação de presença do ser que, ao final das contas, o
leitor vislumbra em todo o signo. Essa impressão é acentuada por dois outros mecanismos
que se lhe acrescentam. 24 PIGNATARI, “Marco Zero de Andrade”, Suplemento Literário de O Estado de São Paulo, 24 out.
1964, apud CAMPOS, Haroldo de. In: ANDRADE, O. de, 1974, p. 30. A respeito desse poema afirmava: O primeiro, como já indicado, é a simulação da publicidade, que o
leitor, a um primeiro olhar, acredita ter sido retirada da paisagem original e afixada em
bruto no poema. O segundo mecanismo, todavia, revela o caráter artificial desse processo. No lugar de simples “transplante do existente”24, a publicidade é readequada a uma intenção
narrativa do eu-lírico que, de início, incorpora-se a um “nós” – “Trazem-nos poemas no
trem” –, identificando-se como um dos viajantes da caravana paulista, para depois descolar-
se deles, quando busca apresentar o hotel familiar e as casas comerciais. Por fim, esse narrador
parece ter sido suprimido, substituído pelos nomes das coisas, que se auto-evidenciam
pura e simplesmente nos versos finais. Há nesses três momentos, aqui descritos, uma
gradação tendente à dissolução dos processos de enunciação convencionais, e mesmo à
desaparição das marcas do enunciador. Poderemos reconhecer nessas escolhas de Oswald de Andrade sua sintonia com as
alternativas encontradas pelas vanguardas de inícios do século XX para a representação
artística. Em especial ressaltaríamos o uso de colagens na pintura de Braque e Picasso, com
efeitos sobre o público bem próximos aos de “aproximação da capital”. Materiais os mais
diversos incorporados à superfície da pintura encontravam-se nos trabalhos desses artistas
desde 1912. Como seria de se esperar, causando a imediata suspeição quanto ao valor das
obras daí resultantes. Mas acima de tudo a fixação desses pedaços de realidade sobre a
pintura colocava em questão a noção de autoria, assim como a do próprio trabalho artístico. Ao mesmo tempo produzia irresistível efeito cômico, originado talvez do desconforto diante
de objetos tão descompromissados da submissão aos padrões mais convencionais da arte. A
ironia que acreditamos permear a poesia de Oswald de Andrade não seria, assim, resultado
exclusivo do uso dessa figura em seus poemas, mas nasceria de seu afastamento com relação
às convenções poéticas de seu tempo. Não se trataria, portanto, da ironia, artifício retórico,
mas dos efeitos gerados pela irreverência do gesto transgressor. 101 2 0 0 6 - jan.-jun. - A L E T R I A Disponível em: http://www.letras.ufmg.br/poslit Disponível em: http://www.letras.ufmg.br/poslit A colagem produz, mais acertadamente, um estado de tensão entre o autoral e o plágio,
entre a superfície e o volume, o espaço circunscrito da pintura e o mundo que se encontra
para além dos limites da tela. A respeito desse poema afirmava: Os objetos colados mantêm a dúbia atitude de se referirem
ainda ao seu contexto próprio, histórico, mas simultaneamente são dele desconectados. Alheios também à pintura, são por ela absorvidos por suas propriedades plásticas de cor,
linha e textura. São assim também pintura, por essas qualidades sensíveis, para logo fazerem
ali pulsar o mundo de onde foram recortados. Se pintores podiam adicionar sobre a tela esses fragmentos imediatamente retirados
do trânsito do mundo, o mesmo, entretanto, não poderia se dar em um poema, objeto de
palavras. Impermeáveis, borzeguins e pijamas, coisas, em suma, se colados sobre uma folha
com poemas, os transformariam imediatamente em artes plásticas. Mesmo exemplares
linguageiros do mundo real, como recortes de jornais, ingressos de espetáculos ou parcelas
de partituras, quando pregados em meio à pintura, transformam o que antes fora
transparência – os suportes desses discursos, o papel entintado – em um novo elemento
plástico da obra. Dessa forma restaria ao poeta transcrever no poema parcelas bem
caracterizadas de gêneros discursivos os mais diversos ou simplesmente reinventá-los em
seu texto. Numa comparação com Picasso e Braque, essas duas medidas corresponderiam,
respectivamente, à colagem propriamente dita e a sua simulação, isto é, à imitação de
objetos colados, produzidos de forma mais ou menos ilusionista, de acordo com a intenção
do artista de evidenciar ou não a sensação ilusória. Em Pau-Brasil os poemas de “História do Brasil”, produzidos com parcelas de textos
de nossos primeiros cronistas, são sem dúvida exemplos de colagem. Em “Roteiro das Minas”
talvez tenhamos apenas um caso desse tipo em “canção do vira”, sem contarmos o título
“menina e moça”, subtraído a Bernardim Ribeiro. Em “convite” e “bumba-meu-boi” teríamos,
ao que nos parece, simplesmente simulações: da linguagem publicitária em “convite” – “Ide
a São João del Rei” – e da fala circense do cicerone de “bumba-meu-boi” – “Vai saí / A
companhia do arraiá / Da Boa Sorte”. Nesse último caso a invenção não se restringiu à
tonalidade do discurso, visto que a localidade citada no poema não existe de fato. Em
“aproximação da capital”, por sua vez, temos possivelmente a formulação de peças publicitárias
a partir de material local disponível, adaptadas à gradação que já indicamos. Todavia esses poucos exemplos não são as únicas formas, nem as mais significativas,
do emprego da colagem em “Roteiro das Minas” e Pau-Brasil. 25 O que evidentemente, em ambos os casos, depende de uma predisposição do observador em ver
nesses fragmentos algo mais que uma provocação. A respeito desse poema afirmava: A fragmentação do discurso nos
poemas oswaldianos indica que esse procedimento se estende para além dos exemplos citados. Uma conseqüência básica da colagem nas artes plásticas é a de os limites dos objetos
colados se demarcarem de alguma maneira do restante da pintura. Caso contrário o efeito da
colagem desapareceria, e o material colado se confundiria com o restante da matéria pictórica. Ora, as fraturas entre segmentos de poemas de Oswald de Andrade rememoram os
efeitos da fragmentação das colagens cubistas. Se nessas obras o processo da colagem é
imediatamente percebido, para só depois se evidenciarem as qualidades plásticas do material
colado, na poesia oswaldiana, da mesma maneira, partimos da impressão de fragmentação
para a observação da plasticidade dos fragmentos25. Os exemplos de colagem citados há 25 O que evidentemente, em ambos os casos, depende de uma predisposição do observador em ver
nesses fragmentos algo mais que uma provocação. 102 A L E T R I A - jan.-jun. - 2 0 0 6 Disponível em: http://www.letras.ufmg.br/poslit Disponível em: http://www.letras.ufmg.br/poslit pouco correspondem a apenas uma faceta do uso do fragmento em poemas de Pau-Brasil. O
fragmento representa, assim, o termo formador da estrutura desses poemas e a colagem, ou
montagem, como bem compreendeu Haroldo de Campos, sua sintaxe.26
AA 6
AA 26 CAMPOS, Haroldo de. In: ANDRADE, O. de, 1974, p. 21. RRRRR É S U M É
É S U M É
É S U M É
É S U M É
É S U M É La reconstitution des donnés du paysage révélent les modes
opératoires du discours poétique de Oswald de Andrade pour
traduire le monde en poésie. Cette traduction est faite par
moyen de la transposition de ressources de la language propres
aux arts plastiques des avant-gards européenes du debut du
XXème siècle a l’univers de la parole. Son résultat a été une
poésie capable de reproduire dans le plan verbal le dynamisme
du monde moderne. Chez Oswald de Andrade, ça a eu, par
conséquence, l’elaboration d’une poésie avec une saveur
primitiviste, proche a laquelle qu’il avait reconnu dans la
peinture cubiste. M
M
M
M
M O T S
O T S
O T S
O T S
O T S ----- C L É S
C L É S
C L É S
C L É S
C L É S
Oswald de Andrade, Pau-Brasil, Peinture et Literature. CAMPOS, Haroldo de. In: ANDRADE, O. de, 1974, p. 21. RRRRR E F E R Ê N C I A S
E F E R Ê N C I A S
E F E R Ê N C I A S
E F E R Ê N C I A S
E F E R Ê N C I A S B I B L I O G R Á F I C A S
B I B L I O G R Á F I C A S
B I B L I O G R Á F I C A S
B I B L I O G R Á F I C A S
B I B L I O G R Á F I C A S ANDRADE, Mário de, ANDRADE, Carlos Drummond de. Carlos e Mário: correspondência
completa. Rio de Janeiro: Bem te vi, 2002. 613 p. ANDRADE, Oswald de. Pau-Brasil. Paris: Au Sans Pareil, 1925, 112 p. ANDRADE, Oswald de. Poesias Reunidas. 4 ed. Acompanhadas por estudo de Haroldo de
Campos, “Uma poética da radicalidade”. Rio de Janeiro: Civilização Brasileira, 1974. (Obras
completas, VII). 203 p. ANDRADE, Oswald de. Os dentes do dragão: entrevistas. Pesquisa, organização, introdução
e notas de Maria Eugenia Boaventura. São Paulo: Globo/Secretaria de Estado da Cultura,
1990. 261 p. (Obras Completas de Oswald de Andrade). ARRIGUCCI JÚNIOR, Davi. Humildade, paixão e morte: a poesia de Manuel Bandeira. São
Paulo: Companhia das Letras, 1990. 301 p. BANDEIRA, Manuel. Estrela da vida inteira. Poesias reunidas. 2 ed. Rio de Janeiro: José
Olympio / INL, 1970. 485 p. BOAVENTURA, Maria Eugênia. O salão e a selva: uma biografia ilustrada de Oswald de
Andrade. Campinas: UNICAMP/Ex Libris, 1995. 286 p. BOAVENTURA, Maria Eugênia. O salão e a selva: uma biografia ilustrada de Oswald de
Andrade. Campinas: UNICAMP/Ex Libris, 1995. 286 p. CHIPP, Herschel Browning. Teorias da arte moderna. 2 ed. São Paulo: Martins Fontes, 1996. 675 p. CHIPP, Herschel Browning. Teorias da arte moderna. 2 ed. São Paulo: Martins Fontes, 1996. 675 p. HARRISSON, Charles. Abstração. In: HARRISSON, et. al., 1998. 103 2 0 0 6 - jan.-jun. - A L E T R I A Disponível em: http://www.letras.ufmg.br/poslit HARRISSON, Charles, et. al. Primitivismo, Cubismo, Abstração: começo do século XX. São
Paulo: Cosac & Naify, 1998. 270 p. LEIBOWITZ, René. Schoenberg. São Paulo: Perspectiva, 1981. 173 p. LEIBOWITZ, René. Schoenberg. São Paulo: Perspectiva, 1981. 173 p. MANFIO, Diléa Zanotto. Poesias reunidas de Oswald de Andrade: edição crítica. São Paulo:
Faculdade de Filosofia, Letras e Ciências Humanas da Universidade de São Paulo, 1992. 3
v. 451 p. (Tese, Doutorado em Literatura Brasileira). PRADO, Paulo. Poesia Pau-Brasil. In: ANDRADE, O. de, 1974, p. 67-71. PRADO, Paulo. Poesia Pau-Brasil. In: ANDRADE, O. de, 1974, p. 67-71. TELES, Gilberto Mendonça. Vanguarda européia e modernismo brasileiro: apresentação dos
principais poemas, manifestos, prefácios e conferências vanguardistas, de 1957 a 1972. 8
ed. Petrópolis, Rio de Janeiro: Vozes, 1985. 446 p. TELES, Gilberto Mendonça. Vanguarda européia e modernismo brasileiro: apresentação dos
principais poemas, manifestos, prefácios e conferências vanguardistas, de 1957 a 1972. 8
ed. Petrópolis, Rio de Janeiro: Vozes, 1985. 446 p. 104 A L E T R I A - jan.-jun. Disponível em: http://www.letras.ufmg.br/poslit RRRRR E F E R Ê N C I A S
E F E R Ê N C I A S
E F E R Ê N C I A S
E F E R Ê N C I A S
E F E R Ê N C I A S B I B L I O G R Á F I C A S
B I B L I O G R Á F I C A S
B I B L I O G R Á F I C A S
B I B L I O G R Á F I C A S
B I B L I O G R Á F I C A S - 2 0 0 6 Disponível em: http://www.letras.ufmg.br/poslit
|
https://openalex.org/W2743791707
|
https://europepmc.org/articles/pmc5549750?pdf=render
|
English
| null |
Occurrence and severity of non-occlusive mesenteric ischemia (NOMI) after cardiovascular surgery correlate with preoperatively assessed FGF-23 levels
|
PloS one
| 2,017
|
cc-by
| 4,785
|
RESEARCH ARTICLE Purpose To evaluate the value of preoperatively assessed fibroblast growth factor 23 (FGF-23) levels
and to correlate FGF-23 with angiographic findings in non-occlusive mesenteric (NOMI)
ischemia using a standardized scoring system. Editor: Abelardo I Aguilera, Hospital Universitario
de la Princesa, SPAIN Jonas Stroeder1*, Matthias Klingele2¤, Hagen Bomberg3, Stefan Wagenpfeil4,
Arno Buecker1, Hans-Joachim Schaefers5, Marcus Katoh6, Peter Minko1 Jonas Stroeder1*, Matthias Klingele2¤, Hagen Bomberg3, Stefan Wagenpfeil4,
Arno Buecker1, Hans-Joachim Schaefers5, Marcus Katoh6, Peter Minko1 Jonas Stroeder1*, Matthias Klingele2¤, Hagen Bomberg3, Stefan Wagenpfeil4,
Arno Buecker1, Hans-Joachim Schaefers5, Marcus Katoh6, Peter Minko1 1 Department of Diagnostic and Interventional Radiology, Saarland University Medical Center, Homburg,
Germany, 2 Department of Internal Medicine IV - Nephrology and Hypertension, Saarland University Medical
Center, Homburg, Germany, 3 Department of Anaesthesiology, Critical Care and Pain Medicine, Saarland
University Medical Center, Homburg, Germany, 4 Institute for Medical Biometry, Epidemiology and Medical
Informatics, Saarland University, Saarland University Medical Center, Homburg, Germany, 5 Department of
Thoracic and Cardiovascular Surgery, Saarland University Medical Center, Homburg, Germany, 6 Helios
Klinikum Krefeld, Clinic for Diagnostic and Interventional Radiology, Krefeld, Germany a1111111111
a1111111111
a1111111111
a1111111111
a1111111111 ¤ Current address: Department of Internal Medicine, Hochtaunuskliniken, Usingen, Germany
* Jonas Stroeder@ ks e ¤ Current address: Department of Internal Medicine, Hochtaunuskliniken, Usingen, Germany
* Jonas.Stroeder@uks.eu * Jonas.Stroeder@uks.eu OPEN ACCESS Citation: Stroeder J, Klingele M, Bomberg H,
Wagenpfeil S, Buecker A, Schaefers H-J, et al. (2017) Occurrence and severity of non-occlusive
mesenteric ischemia (NOMI) after cardiovascular
surgery correlate with preoperatively assessed
FGF-23 levels. PLoS ONE 12(8): e0182670. https://
doi.org/10.1371/journal.pone.0182670 Materials and methods Between 2/2011 and 3/2012 a total of 865 patients (median age: 67 years) underwent car-
diovascular surgery during this ethics committee approved, prospective study. 65 of these
patients had clinical suspicion of NOMI and consequently underwent catheter angiography
of the superior mesenteric artery. Images were assessed using a standardized reporting
system (Homburg-NOMI-Score). These data were correlated to following preoperative
parameters of kidney function: cystatin C, creatinine, FGF-23 and estimated glomerular fil-
tration rate (eGFR), and outcome data (death, acute renal failure) using linear and logistic
regressions, as well as nonparametric tests. Copyright: © 2017 Stroeder et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which
permits unrestricted use, distribution, and
reproduction in any medium, provided the original
author and source are credited. Data Availability Statement: All relevant data are
within the paper. If additional data should be
needed, please contact the author JS. Conclusions FGF-23 significantly correlates with the severity of NOMI, which is in contrast to other renal
function parameters. The applied scoring system allows to predict mortality in NOMI patients. Results Significant correlations were found between FGF-23 and the angiographic appearance of
NOMI (p = 0.03). Linear regression analysis showed no significant correlation to the severity
of NOMI with creatinine (p = 0.273), cystatin C (p = 0.484), cystatin C eGFR (p = 0.914) and
creatinine eGFR (p = 0.380). Logistic regression revealed a significant correlation between
death and the Homburg-NOMI-Score (p<0.001), but not between development of NOMI Funding: The authors received no specific funding
for this work. Competing interests: The authors have declared
that no competing interests exist. PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 1 / 9 NOMI after cardiovascular surgery correlates with preoperative FGF-23 levels and acute renal failure (p = 0.122). The ROC Analysis yielded an area under the curve of
0.695 (95% CI: 0.627–0.763) with a sensitivity of 0.672 and specificity of 0.658. Introduction Non occlusive mesenteric ischemia (NOMI) is a rare (incidence around 1%)[1] but feared
(mortality up to 90%)[2] disease, in which the perfusion of the intestine is limited. It is
believed, that a reduction of splanchnic blood flow causes an intestinal ischemia. This can lead
to severe damage in the mucosal layer resulting in bacterial translocation and bacteremia,
which finally may lead to multi organ failure[3]. In the diagnosis of NOMI, invasive angiogra-
phy with digital subtraction angiography (DSA) is considered to be the gold standard[4]. The
therapy for NOMI is to correct underlying vascular pathology and diffuse vasospasm with
application of vasodilatators[5–7], which is done selectively through an angiographically
placed catheter in the superior mesenteric artery (SMA). Clinical presentation of NOMI is
manifold and poses a diagnostic challenge, as clinical signs such as oliguria, rising serum lac-
tate levels, decreased blood oxygenation, hypertension and abdominal pain are nonspecific. Moreover in patients who receive an analgosedation therapy, abdominal pain might be
completely masked. Several risk factors for NOMI have been identified in the past including
renal insufficiency[3,8,9] and coronary heart disease[1,9]. These risk factors also seem to influ-
ence the blood level of fibroblast growth factor 23 (FGF-23)[10]. FGF-23 is a protein consisting of 251 amino acids[11], which is mainly synthesized in the
osteocytes and osteoblasts in the bone[12]. FGF-23 is an endocrine signaling protein[13],
which plays an important role in several metabolic pathways, including the Vitamin D and
phosphate regulation. Increased blood levels of FGF-23 are described in patients with chronic
renal disease and to be a predictor of the mortality in dialysis patients [14]. This positive asso-
ciation of FGF-23 levels and mortality are in contrast to other cardiovascular markers, which
seem to be protective of cardiovascular death in this group of patients[14]. Furthermore, some
studies even show that elevated FGF-23 levels were associated with an increased risk for car-
diovascular death, regardless of chronic kidney disease[10]. Additionally, it has recently been
shown that FGF-23 is a predictor of death in patients suffering from myocardial infarction and
cardiogenic shock[15]. The aim of our study was to prospectively evaluate the value of preoperatively assessed
FGF-23 levels for NOMI and to correlate FGF-23 levels with angiographic findings using a
standardized scoring system. Furthermore we investigated the clinical value of angiography
in predicting the outcome in patients after cardiovascular surgery with clinical suspicion of
NOMI. For the actual evaluation, 4 patients had to be excluded due to
missing laboratory data, an additional 22 patients had to be excluded because of technical
reasons leading to incomplete angiographic data. Of these 839 patients 65 patients (24 female;
41 male) were under clinical suspicion of NOMI. They suffered from at least one of the follow-
ing: new onset of oliguria (urine output <0.5 ml/kg/h for at least 6 h) or anuria, distention
of the abdomen with decreased or absent bowel sounds, elevated serum lactate levels > 5.0
mmol/l or metabolic acidosis (base excess > -5 mmol/l). These patients will be called the
“NOMI-Group” and underwent a diagnostic angiogram of the superior mesenteric artery as
soon as the clinician suspected NOMI. The other patients are consequently considered the
“Non-NOMI-Group”. Patient characteristics are displayed in Table 1. NOMI after cardiovascular surgery correlates with preoperative FGF-23 levels Table 1. Patient characteristics. All Patients
p-Value
(2-sided)
All
No NOMI
NOMI
n
Median
Range
n
Median
Range
n
Median
Range
Age
839
67.0
[19.3;88.5]
774
66.1
[19.3; 88.5]
65
74.4
[46.8; 88.2]
<0.001*
BMI
839
27.2
[16.5;46.4]
774
27.1
[16.5; 45.7]
65
28.7
[19.4; 46.4]
0.133
FGF-23 [RU/ml]
839
64.2
[7.3;53110]
774
61.9
[7.3; 53110]
65
108.5
[22.5; 16959.5]
<0.001*
Kreatinin [mg/dl]
839
1.0
[0.5;11.4]
774
1.0
[0.5; 11.4]
65
1.2
[0.7; 3.8]
0.001*
Cystatin C [mg/l]
838
1.06
[0.4;7]
773
1.04
[0.4; 7]
65
1.52
[0.4; 5.4]
<0.001*
Urea [mg/dl]
839
40.0
[13;222]
774
39.0
[13; 222]
65
49.0
[18; 192]
<0.001*
GFR MDRD
839
72.95
[3.63; 146.77]
774
73.83
[3.63; 146.77]
65
56.82
[17.27; 117.04]
<0.001*
CKD-EPI cystatin C
838
68.05
[5.49; 156.64]
773
70.31
[5.49; 156.64]
65
39.48
[8.31; 144.81]
<0.001*
CKD-EPI creatinin
839
72.02
[3.21; 131.72]
774
73.15
[3.21; 131.72]
65
52.53
[16.04; 101.49]
<0.001*
Hospital stay [days]
839
9
[1;84]
774
9
[1; 84]
65
16
[2; 77]
<0.001*
ICU stay [days]
839
1
[0;54]
774
1
[0; 54]
65
7
[0; 46]
<0.001*
OP-duration [min]
839
161
[45;651]
774
160
[45; 651]
65
206
[77; 450]
<0.001*
LOS
839
13
[0;132]
774
13
[0; 112]
65
24
[0; 132]
<0.001*
Patient characteristics and results of Mann-Whitney-U-Test performed to compare Groups with and without NOMI. Significant differences between groups
are marked with an asterisk (*) in the last column. n indicates absolute frequency. Table 1. Patient characteristics. Patient characteristics and results of Mann-Whitney-U-Test performed to compare Groups with and without NOMI. Significant differences between groups
are marked with an asterisk (*) in the last column. n indicates absolute frequency. observational study. The study was approved by the local ethics committee. Finally, 865
patients could be included and underwent preoperative measure of blood levels of FGF-23,
creatinine and cystatin C. Written informed consent was obtained from all participants. Exclu-
sion criteria were age < 18 years and cases in which informed consent to participate in the
study could not be obtained. The recruited patient collective is the same as used by Speer et al. [16] who focused on cardiovascular mortality, but as we focused on the severity of NOMI we
based our research on the angiographic findings. Consequently, we had to exclude several
patients for different reasons. Selection of patients Between February 2011 and March 2012 all patients undergoing cardiac surgery at our depart-
ment of Thoracic and Cardiovascular Surgery were screened for participation in a prospective 2 / 9 PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 https://doi.org/10.1371/journal.pone.0182670.t001 PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 Patient characteristics and results of Mann-Whitney-U-Test performed to compare Groups with and without NOMI. Significant differences between groups
are marked with an asterisk (*) in the last column. n indicates absolute frequency. Assessment of laboratory values The blood samples were each taken under standard conditions alongside other routine preop-
erative laboratory assessments directly prior to surgery. The blood samples for the FGF-23 measurement were centrifuged at 2800 x g for ten min-
utes at 4˚C. Supernatants were stored in aliquots at −80˚C. C-terminal FGF-23 levels were
measured from plasma samples by ELISA (Immutopics, San Clemente, CA, USA) in relative
Units per milliliter (RU/mL). Serum creatinine was measured using a Jaffe-Test. The assessed creatinine values were used
to calculate the Creatinine-GFR values using the CKD-EPI formula[17]. Cystatin C was 3 / 9 PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 NOMI after cardiovascular surgery correlates with preoperative FGF-23 levels Fig 1. Angiographic findings in mild and severe NOMI. Comparison of angiographic findings in a patient with a low FGF-23 value
of 29 (A, Score of 1 due to a slight reflux into the aorta and no signs of vasospasm and no delayed portal vein filling) and a patient with
a high FGF-23 value of 4636 and a severe NOMI (B, Score of 9 due to severe vasospasm and reflux into the aorta as well as delayed
portal vein filling). Fig 1. Angiographic findings in mild and severe NOMI. Comparison of angiographic findings in a patient with a low FGF-23 value
of 29 (A, Score of 1 due to a slight reflux into the aorta and no signs of vasospasm and no delayed portal vein filling) and a patient with
a high FGF-23 value of 4636 and a severe NOMI (B, Score of 9 due to severe vasospasm and reflux into the aorta as well as delayed
portal vein filling). https://doi.org/10.1371/journal.pone.0182670.g001 measured using a particle-enhanced turbodimetric test and the Cystatin C-GFR was conse-
quently calculated using the CKD-EPI formula for Cystatin C. Assessment of NOMI All of these 65 patients underwent a routine standardized invasive angiographic procedure
through a transfemoral 5F sheath placed in the common femoral artery. Subsequently the
SMA was catheterized using a 4F catheter (Cordis, Bridgewater, USA) with a cobra tip configu-
ration. The tip of the catheter was placed in the main stem of the SMA. A DSA was performed
after application of 25 ml Imeron 300 (Bracco, Italy) at a rate of 5 ml/s in every case (Fig 1). The injection was performed using a single-head injector Injektron 82 (Medtronic, Saar-
bruecken, Germany). The series was recorded using a framerate of 2 frames per second until
the portal vein was contrasted. Afterwards, these angiograms were assessed and consecutively
scored by two experienced radiologists on consensus basis, using a modification of the „Hom-
burg-NOMI-Score”published in 2012[18], the simplified version of the score published in
2014[19]. This simplified NOMI score (consisting of three categories namely vessel morphol-
ogy, reflux of contrast medium into the aorta and time to portal vein filling) was used because
it showed higher interobserver correlations and is easier to apply than the original score[18]. Furthermore, previously conducted studies showed even better correlation to mortality than
the complete NOMI score[19]. Therefore the term Homburg-NOMI-Score will be used for the
applied simplified version of the NOMI scoring system. Results The patients under suspicion of NOMI had an average Homburg-NOMI-Score of 3.2 (range
1–7, median 3). No significant difference between the patients suffering from NOMI and those without
NOMI was found concerning sex distribution (p = 0.302) and BMI (median: 28.7 vs. 27.1;
p = 0.133). There was a significant difference between the two groups concerning age (median: 66.1 vs. 74.4; p<0.001), FGF-23 (median: 61.9 vs. 108.5; p<0.001), Creatinine (median: 1.0 vs. 1.2;
p<0.001), Cystatin C (median: 1.04 vs. 1.52; p<0.001), Creatinine-GFR (median: 73.15 vs. 52.53; p<0.001) and Cystatin C-GFR (median: 70.31 vs. 39.48; p<0.001). All these values were
significantly higher in the NOMI group, except for the calculated GFRs which were lower. For
further details see Table 1. The ROC Analysis concerning FGF-23 values and the occurrence of NOMI yielded an area
under the curve of 0.695 (95% CI: 0.627–0.763) with a sensitivity of 0.672 and specificity of
0.658 for a FGF-23 value of 82.545. In the NOMI-group, significant correlations were found between FGF-23 and the Hom-
burg-NOMI-Score (p = 0.03). No significant correlation to the severity of NOMI was found
for creatinine (p = 0.273), cystatin C (p = 0.484), cystatin C eGFR (p = 0.914) and creatinine
eGFR (p = 0.380) as shown in Table 2. Patients without clinical suspicion of NOMI did not
undergo angiography and therefore could not be evaluated in this regard. Correlation of FGF-23 and time to portal vein filling showed a tendency with a p-value
of 0.09, but did not reach statistical significance. The same is true of the reflux of contrast
medium into the aorta (p = 0.07). Logistic and Cox regression models revealed a significant correlation between death and
the Homburg-NOMI-Score (p<0.001). No significant correlation was found for the Logistic and Cox regression models revealed a significant correlation between death and
the Homburg-NOMI-Score (p<0.001). No significant correlation was found for the Table 2. Results of linear regression analysis. Statistics Comparison between the NOMI and the Non-NOMI group was performed using the Mann-
Whitney-U-Test and Chi-square-Test. In addition, a ROC- Analysis for the FGF-23 values was 4 / 9 PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 NOMI after cardiovascular surgery correlates with preoperative FGF-23 levels conducted. NOMI-Score values were then investigated with respect post-operative mortality
rate using logistic regression analysis. Cox regression was used to analyze time-to-event data. In addition, the influence of preoperative blood values (serum levels of FGF-23, cystatin C, cre-
atinine as well as calculated GFR for serum creatinine and for serum cystatin) on the angio-
graphic score was investigated using linear regression analysis. All analyses were performed
using SPSS Version 20 (IBM, Armonk, NY, USA). We used the natural logarithm (ln) of the
FGF-23 values as they provided a better fit of the linear regression models. Consequently, this
enabled the use of these models to assess the FGF-23 values in combination with the values
resulting from the NOMI score. Any p-values given are two-sided and subject to a significance
level of 0.05. NOMI-Score correlates significantly with FGF-23, but not with other renal function parameters. Significant findings Discussion NOMI is a severe condition, which might occur after cardiovascular surgery or in the course
of dialysis therapy, but hardly any predictors are known thus far. Various studies about risk
factors for NOMI have been conducted and several risk factors have been successfully identi-
fied[1,20]. Through the course of this study, significant differences between the NOMI and
Non-NOMI-Group regarding age, cystatin, creatinine and duration of the operation were
found. These significant differences between the groups among risk factors for NOMI are sim-
ilar to the risk factors identified by Groesdonk et al. in 2013[1]. Among these risk factors sev-
eral parameters for cardiac and renal insufficiency have been reported. As FGF-23 levels are
known to be elevated in these conditions, we suspected them to be elevated in patients at risk
for NOMI as well. We could show that preoperative FGF-23 values of patients with angio-
graphic prove of NOMI are significantly higher than those of Patients showing no clinical
signs of NOMI. Additionally, we were able to show for the first time that the preoperative
FGF-23 levels correlated with the severity of the NOMI seen by DSA. These findings lead to
the conclusion that the preoperative determination of FGF-23 might be of value in the predic-
tion of the occurrence of postoperative NOMI, even though only a sensitivity of 67% and a
specificity of 66% could be identified. Whether a combination of FGF-23 and other parameters
or a postoperative FGF-23 leads to a better sensitivity and specificity has still to be investigated. The assessment of the severity of NOMI using the Homburg-NOMI-Score has shown a
highly significant (p<0.001) correlation to the event of death during the postoperative period
[19]. These data could be confirmed in our patient collective and thus further support the qual-
ity and value of the applied scoring system. Reproducibility of the score has previously been
reported which is needed to have a clinical impact. In addition, a standardized reporting sys-
tem will help clinicians to act accordingly and thus facilitate standardization of clinical path-
ways in this multifactorial disease. The reproducibility enables the clinician to be able to use
follow-up examinations to see effects and adapt the applied therapy, which is currently under
investigation. NOMI after cardiovascular surgery correlates with preoperative FGF-23 levels Table 3. Results of logistic and Cox regression analysis. Logistic Regression
Cox Regression
NOMI Score
NOMI Score
P-value
Odds Ratio
P-value
Hazard Ratio
ARF
0.144
1.391
0.037*
1.193
Death
< 0.001*
2.957
< 0.001*
2.425
NOMI-Score correlates significantly with death, but not with acute renal failure (ARF). Significant findings are marked with an asterisk (*). Table 3. Results of logistic and Cox regression analysis. https://doi.org/10.1371/journal.pone.0182670.t003 development of acute renal failure (p = 0.144) using logistic regression analysis, but a correla-
tion was found using Cox regression analysis (p = 0.037) as can be seen in Table 3. Results NOMI Score
Vessel Morphology
CM-Reflux to Aorta
Time to portal vein filling
p-Value
Estimated Effect
p-Value
Estimated Effect
p-Value
Estimated Effect
p-Value
Estimated Effect
Ln FGF-23
0.030*
0.296
0.382
0.073
0.065
0.128
0.086
0.096
Cystatin C [mg/l]
0.484
0.201
0.872
0.028
0.981
-0.003
0.127
0.177
Kreatinin [mg/dl]
0.273
0.478
0.143
0.383
0.290
-0.233
0.061
0.328
CKD-EPI cystatin C
0.914
-0.001
0.960
0.000
0.941
0.000
0.776
-0.001
CKD-EPI creatinin
0.380
-0.009
0.204
-0.008
0.381
0.005
0.166
-0.006
NOMI S
l t
i
ifi
tl
ith FGF 23 b t
t
ith th
l f
ti
t
Si
ifi
t fi di
k d
ith
t
i k (*) Table 2. Results of linear regression analysis. https://doi.org/10.1371/journal.pone.0182670.t002 PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 5 / 9 PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 Discussion In current literature there is a certain interest to perform a computed tomography as a first
line technique in such a setting [21], but it has not found entry into current guidelines and it
does not allow for immediate treatment, if NOMI is detected. As the pathophysiology of NOMI is not completely understood, it is known to be a multi-
factorial disease in which organ systems interacting with FGF-23 might play a major role. However, FGF-23 might be just a marker and not the cause of NOMI. Furthermore, the pre-
operative levels of FGF-23 might as well indicate a preoperative condition of an organ mal-
function that severely aggravates during/after cardiovascular surgery and the following
ICU stay. Assessing the preoperative values of FGF-23 was used in this study to identify a PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 6 / 9 NOMI after cardiovascular surgery correlates with preoperative FGF-23 levels parameter mirroring the cardiac and renal health condition of the patients. Other renal
function parameters were also taken into account, to avoid assessing the severity of their
impairment due to the surgical procedure. By correlating the preoperative blood levels of
FGF-23 to the severity of NOMI we have found a parameter which could be useful in clinical
practice. It might be advantageous to preoperatively know, which patients have an increased
risk to suffer from severe NOMI. These patients could profit from added caution to detect
and treat the NOMI as early as possible. This also poses one limitation of the study, as no
FGF-23 values were obtained directly before the angiography and thus no acute change in
FGF-23 levels were investigated. Furthermore it could have been of interest to also evaluate
postoperative FGF-values but as we were looking for a predictor, this can be done in follow-
ing studies. NOMI has been shown to be in great parts related to cardiovascular factors, especially those
resulting in low cardiac output, but has also been shown to correlate with renal insufficiency
[11,15,17]. Other results supporting these findings show FGF-23 to be increased in patients
with renal insufficiency and at elevated risk of NOMI which contributes to overall mortality; a
correlation of FGF-23 and cardiovascular mortality had already been shown by Speer et al[16]. Discussion A direct correlation between death and the FGF-23 levels could not be shown in this study, but
a tendency could be detected to support this theory as the calculated p-value was 0.07. This
could be due to the nature of the FGF-23 blood levels to be influenced by the working state of
more than one organ system. Further pathophysiological research taking into account the
blood levels of FGF-23 should be conducted. There are no data available about correlations between preoperative FGF-23 and the mor-
tality of patients suffering from an untreated NOMI. These data will be difficult to obtain, as
therapeutic approaches have been identified to improve patient conditions. Consequently, it
would be unethical not to treat patients with NOMI accordingly. There was no angiography
performed in the non-NOMI-group because these patients should not be put in jeopardy to
suffer a complication of angiographies, even though these are rare. Consequently, some of
these patients might have suffered from a subclinical course of a NOMI. In conclusion, this prospective study showed that preoperative FGF-23 significantly corre-
lates with the angiographic signs for severity of NOMI and the applied Homburg-NOMI-Score
allows to predict fatal outcome in NOMI patients thus FGF-23 proved to be an important pre-
operative marker in patients undergoing cardiovascular surgery and might help to identify
patients with a high risk of NOMI and to improve postoperative outcome; catheter angiogra-
phy should be analyzed using the previously published score. Writing – review & editing: M. Klingele HB SW AB HS M. Katoh. PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 References 1. Groesdonk HV, Klingele M, Schlempp S, Bomberg H, Schmied W, Minko P, et al. Risk factors for non-
occlusive mesenteric ischemia after elective cardiac surgery. J Thorac Cardiovasc Surg. 2013; 145:
1603–10. https://doi.org/10.1016/j.jtcvs.2012.11.022 PMID: 23219496 2. Howard TJ, Plaskon L a., Wiebke E a., Wilcox MG, Madura J a. Nonocclusive mesenteric ischemia
remains a diagnostic dilemma. Am J Surg. 1996; 171: 405–408. https://doi.org/10.1016/S0002-9610
(97)89619-5 PMID: 8604831 3. Trompeter M, Brazda T, Remy CT, Vestring T, Reimer P. Non-occlusive mesenteric ischemia: Etiology,
diagnosis, and interventional therapy. Eur Radiol. 2002; 12: 1179–1187. https://doi.org/10.1007/
s00330-001-1220-2 PMID: 11976865 4. Hirsch AT, Haskal ZJ, Hertzer NR, Bakal CW, Creager MA, Halperin JL, et al. ACC/AHA 2005 Practice
Guidelines for the management of patients with peripheral arterial disease (lower extremity, renal,
mesenteric, and abdominal aortic): a collaborative report from the American Association for Vascular
Surgery/Society for Vascular Sur. Circulation. 2006; 113: e463–e654. https://doi.org/10.1161/
CIRCULATIONAHA.106.174526 PMID: 16549646 5. Kamimura K, Oosaki A, Sugahara S, Mori S. Survival of Three Nonocclusive Mesenteric Ischemia
Patients following Early Diagnosis by Multidetector Row Computed Tomography and Prostaglandin E1
Treatment. Intern Med. 2008; 47: 2001–2006. https://doi.org/10.2169/internalmedicine.47.1213 PMID:
19015617 6. Abboud B, Daher R, Boujaoude J. Acute mesenteric ischemia after cardio-pulmonary bypass surgery. World J Gastroenterol. 2008; 14: 5361–5370. PMID: 18803347 7. Sommer CM, Radeleff B a. A novel approach for percutaneous treatment of massive nonocclusive
mesenteric ischemia: Tolazoline and glycerol trinitrate as effective local vasodilators. Catheter Cardio-
vasc Interv. 2009; 73: 152–155. https://doi.org/10.1002/ccd.21811 PMID: 19156878 8. John AS, Tuerff SD, Kerstein MD. Nonocclusive mesenteric infarction in hemodialysis patients. J Am
Coll Surg. 2000; 190: 84–88. https://doi.org/10.1016/S1072-7515(99)00226-4 PMID: 10625237 9. Ori Y, Chagnac A, Schwartz A, Herman M, Weinstein T, Zevin D, et al. Non-occlusive mesenteric ische-
mia in chronically dialyzed patients: A disease with multiple risk factors. Nephron—Clin Pract. 2005;
101. https://doi.org/10.1159/000086346 PMID: 15956804 10. Seiler S, Cremers B, Rebling NM, Hornof F, Jeken J, Kersting S, et al. The phosphatonin fibroblast
growth factor 23 links calciumphosphate metabolism with left-ventricular dysfunction and atrial fibrilla-
tion. Eur Heart J. 2011; 32: 2688–2696. https://doi.org/10.1093/eurheartj/ehr215 PMID: 21733911 11. Yamashita T, Yoshioka M, Itoh N. Identification of a novel fibroblast growth factor, FGF-23, preferen-
tially expressed in the ventrolateral thalamic nucleus of the brain. Biochem Biophys Res Commun. 2000; 277: 494–498. https://doi.org/10.1006/bbrc.2000.3696 PMID: 11032749 12. Riminucci M, Collins MT, Fedarko NS, Cherman N, Corsi A, White KE, et al. Conceptualization: JS PM. Conceptualization: JS PM. Formal analysis: SW. Investigation: M. Klingele HB HS M. Katoh PM. Project administration: M. Klingele JS. Resources: HS AB M. Klingele PM HB. Visualization: SW JS. Writing – original draft: JS PM M. Klingele. Writing – review & editing: M. Klingele HB SW AB HS M. Katoh. Formal analysis: SW. Formal analysis: SW. Investigation: M. Klingele HB HS M. Katoh PM. Project administration: M. Klingele JS. Resources: HS AB M. Klingele PM HB. Visualization: SW JS. Writing – original draft: JS PM M. Klingele. Writing – review & editing: M. Klingele HB SW AB HS M. Katoh. Investigation: M. Klingele HB HS M. Katoh PM. Investigation: M. Klingele HB HS M. Katoh PM. 7 / 9 PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 NOMI after cardiovascular surgery correlates with preoperative FGF-23 levels PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 20.
Yu C-C, Hsu H-J, Wu I-W, Lee C-C, Tsai C-J, Chou C-C, et al. Factors associated with mortality from
non-occlusive mesenteric ischemia in dialysis patients. Ren Fail. 2009; 31: 802–806. https://doi.org/10.
3109/08860220903180624 PMID: 19925288 21.
Barrett T, Upponi S, Benaglia T, Tasker a D. Multidetector CT findings in patients with mesenteric
ischaemia following cardiopulmonary bypass surgery. Br J Radiol. 2013; 86: 20130277. https://doi.org/
10.1259/bjr.20130277 PMID: 23966376 PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 NOMI after cardiovascular surgery correlates with preoperative FGF-23 levels References FGF-23 in fibrous dysplasia
of bone and its relationship to renal phosphate wasting. J Clin Invest. 2003; 112: 683–692. https://doi. org/10.1172/JCI18399 PMID: 12952917 13. Yamashita T. Structural and biochemical properties of fibroblast growth factor 23. Ther Apher Dial. 2005; 9: 313–318. https://doi.org/10.1111/j.1744-9987.2005.00288.x PMID: 16076373 14. Heine GH, Seiler S, Fliser D. FGF-23: the rise of a novel cardiovascular risk marker in CKD. Nephrol
Dial Transplant. 2012; 27: 3072–81. https://doi.org/10.1093/ndt/gfs259 PMID: 22851630 15. Fuernau G, Po¨ss J, Denks D, Desch S, Heine GH, Eitel I, et al. Fibroblast growth factor 23 in acute myo-
cardial infarction complicated by cardiogenic shock : a biomarker substudy of the Intraaortic Balloon
Pump in Cardiogenic Shock II (IABP-SHOCK II) trial. Crit Care. 2014; 1–9. https://doi.org/10.1186/
s13054-014-0713-8 PMID: 25528363 16. Speer T, Groesdonk H V, Zapf B, Buescher V, Beyse M, Duerr L, et al. A single preoperative FGF23
measurement is a strong predictor of outcome in patients undergoing elective cardiac surgery: a pro-
spective observational study. Crit Care.???; 2015; 19: 1–10. 17. Levey AS, Stevens LA, Schmid CH, Zhang YL, Castro AF, Feldman HI, et al. A new equation to esti-
mate glomerular filtration rate. Ann Intern Med. 2009; 150: 604–12. PMID: 19414839 18. Minko P, Groesdonk H, Stroeder J, Miodek J, Graeber S, Bu¨cker A, et al. A scoring system for the
assessment of angiographic findings in non-occlusive mesenteric ischemia (NOMI). Rofo. 2012; 184:
805–9. https://doi.org/10.1055/s-0032-1312750 PMID: 22618477 19. Minko P, Stroeder J, Groesdonk H V, Graeber S, Klingele M, Buecker A, et al. A scoring-system for
angiographic findings in nonocclusive mesenteric ischemia (NOMI): correlation with clinical risk factors
and its predictive value. Cardiovasc Intervent Radiol. 2014; 37: 657–63. https://doi.org/10.1007/
s00270-014-0844-y PMID: 24477566 8 / 9 PLOS ONE | https://doi.org/10.1371/journal.pone.0182670
August 8, 2017 NOMI after cardiovascular surgery correlates with preoperative FGF-23 levels NOMI after cardiovascular surgery correlates with preoperative FGF-23 levels 9 / 9
|
https://openalex.org/W4206189707
|
https://riunet.upv.es/bitstream/10251/191308/1/Molero-AlabauFambuenaCliment%20-%20Electrocardiographic%20Imaging%20in%20Atrial%20Fibrillation%20Selection%20of%20t....pdf
|
English
| null |
Electrocardiographic Imaging in Atrial Fibrillation: Selection of the Optimal Tikhonov-Regularization Parameter
|
2021 Computing in Cardiology (CinC)
| 2,021
|
cc-by
| 2,674
|
Abstract Electrocardiographic
imaging
(ECGI)
allows
evaluating the complexity of atrial fibrillation (AF) signals
using the Boundary Element Method and Tikhonov
regularization. An accurate ECGI reconstruction is
dependent on a proper selection of the regularization
parameter (λ). In this work, two ranges of λ are explored
to evaluate the effect of λ on the quality of the ECGI
reconstruction. ECGIs of 20 AF patients were computed using zero
(T0), first (T1) and second (T2) order Tikhonov
regularization (TR) for two ranges of λ: from 10-9 to 102
and 10-12 to 10-4. Dominant frequencies (DF) and the
number of rotors obtained with the two ranges and
methods were compared. In the present study, two different ranges of λ are
explored to compute the ECGI in real AF signals using
zero, first and second order TR. The premise of this study
is that ECGI with a good reconstruction and a correct λ
selection will present lower differences between TR
orders, this difference is expected to be reflected in the
resulting maps and non-invasive metrics as well. Zero-order Tikhonov showed to be more robust in λ
selection for different λ ranges. For lower λ ranges, higher
DF was found (T2, p<0.05) and more rotors were detected
for T1 and T2 (p<0.01). Differences between TR methods
compared by λ ranges showed more variability in derived
metrics for lower λ range (p<0.01). Optimal ranges for λ search differ among T0, T1 and
T2. Election of lower than optimal λ values result in an
increased estimated electrical complexity. 1ITACA Institute, Universitat Politècnica de València, Valencia, Spain Tikhonov regularization (TR) the most widely used. Election of the regularization parameter is usually
accomplished by the L-curve method, which is based on
minimizing both the norm of the regularized solution and
the norm of the residual vector [3]. Tikhonov
regularization method has a good performance in models
of AF signals [4], but in real scenarios, the complexity and
the noise of the signals affect the selection of λ. Higher λ
can result in an oversmoothed ECGI, hindering an
underlying atrial electrical complexity, and on the
contrary, λ values closer to zero are more sensitive to little
changes of the signal, amplifying artifacts caused by noise
that for AF are difficult to remove. A correct λ selection
depends on the performance of the method but this
selection is totally dependent on the range searched for
selecting the regularization parameter. Tikhonov regularization (TR) the most widely used. Election of the regularization parameter is usually
accomplished by the L-curve method, which is based on
minimizing both the norm of the regularized solution and
the norm of the residual vector [3]. Tikhonov
regularization method has a good performance in models
of AF signals [4], but in real scenarios, the complexity and
the noise of the signals affect the selection of λ. Higher λ
can result in an oversmoothed ECGI, hindering an
underlying atrial electrical complexity, and on the
contrary, λ values closer to zero are more sensitive to little
changes of the signal, amplifying artifacts caused by noise
that for AF are difficult to remove. A correct λ selection
depends on the performance of the method but this
selection is totally dependent on the range searched for
selecting the regularization parameter. Page 1 ISSN: 2325-887X DOI: 10.22489/CinC.2021.216 Page 1 ISSN: 2325-887X DOI: 10.22489/CinC.2021.216 2.1.
Data collection and preprocessing Electrocardiographic imaging (ECGI) is a non-invasive
technique that allows computing the epicardial activity by
means of the solution of the inverse problem of
electrocardiography by using surface electrograms and the
geometry of the torso and heart of the patient. ECGI can be
used to evaluate the complexity of atrial fibrillation (AF)
signals, with some correlation with intracardiac mapping
[1]. Despite the demonstrated reliability of ECGI
reconstructions, the obtention of ECGI signals is an ill-
conditioned problem with an unknown solution, which
specially for AF, is strongly dependent on the noise and
quality of the signals. The electrical activity of 20 AF patients (10 females and
10 males; 63.1 ± 7.9 years old) was recorded through Body
Surface Potential Mapping with 64 electrodes prior to
pulmonary vein isolation (PVI). The torso geometry of the
patients and the position of electrodes were reconstructed
using photogrammetry of a video of the patient [1]. The
heart anatomy of each patient was obtained from a
database of MRI segmented atria, by selecting the most
appropriate based on the torso’s geometries. Base line of surface electrograms was removed, signals
were band-pass filtered between 2 and 45 Hz. One signal
per patient was selected with a mean duration of 4.61 ±
0.52s and ventricular activity was removed by using the
Principal Component Analysis approach described in [5]. The inverse problem of electrocardiography has been
studied by several approaches [2], being zero-order 2.
Material and methods 2. 2.2.
Inverse problem and regularization
parameter selection To compute the ECGI of each patient, the inverse
problem of each signal is computed using Tikhonov
regularization (TR) and L-curve optimization [6]. Tikhonov regularization allows estimating the epicardial
potentials (x) by minimizing the following equation: Figure 1. Dominant frequency (A) and singularity point
maps (B) from an atrial fibrillation signal obtained by
Tikhonov regularization of zero, first, and second-order
(T0, T1, and T2). The first row of each panel represents the
solution using an optimal regularization parameter (λ) and
the second row a sub-optimal λ. ‖Ax − b‖2 + 𝜆‖Lx‖2 (1) (1) Where b are torso potentials and A the transfer matrix
calculated using the Boundary Element Method between
torso and atria geometries. In this study, we used three
Tikhonov orders where L is a square matrix that is the
identity matrix in zero-order Tikhonov, (T0), the gradient
operator in first-order (T1), and the Laplacian operator in
second-order Tikhonov (T2) [4]. For each method, the
regularization parameter chosen is the one that minimizes
equation 1. In this study, two ranges of λ were studied and
compared
using
three
different
order
Tikhonov
regularization methods: a high range from 10-9 to 102 and
a lower range from 10-12 to 10-4. Computing in Cardiology 2021; Vol 48 Computing in Cardiology 2021; Vol 48 maps, leading to non-interpretable and coherent results,
which suggest that ECGI reconstruction was more affected
by noise. 2.3.
ECGI derived metrics and statistical
analysis After computing ECGI for both ranges and three
methods, the highest dominant frequency (HDF) [7] and
rotors were computed [8]. Both metrics were compared for
each Tikhonov solution in both λ ranges. Absolute
difference between ECGI solutions obtained with different
Tikhonov orders were computed and compared between
ranges. Statistical comparisons were calculated using
paired t-student test and Wilcoxon rank-sum test when the
normality of the metrics was not present. A p-value<0.05
was considered statistically significant. Figure 1. Dominant frequency (A) and singularity point
maps (B) from an atrial fibrillation signal obtained by
Tikhonov regularization of zero, first, and second-order
(T0, T1, and T2). The first row of each panel represents the
solution using an optimal regularization parameter (λ) and
the second row a sub-optimal λ. Two λ ranges were compared in 20 AF signals and the
selected λ are represented in Fig 2. Optimal λ found in the
higher range (dots) appeared in a narrow range of values
with no overlap between ranges for T0 (10-6 to 10-4), T1
(10-2 to 1) and T2 (1 to 100). The highest λ range showed
lower variability of the optimal selection between patients
with lower values for T0 compared to higher TR orders. However, when the studied λ range was lower, the
variability of the λ selection between patients was higher. Zero-order Tikhonov, showed more similar results
between λ ranges, being more consistent since the optimal
λ belongs to the region for λ search that overlaps in both
ranges. The first and second order, presented more disperse
and lower λ between patients, tending to 0. 3.1.
Regularization parameter range and
optimal selection An example of how an appropriate range of λ affects
ECGI derived maps is presented in Fig. 1. Dominant
frequency maps (Fig. 1A) and singularity point (SP)
histograms (Fig. 1B) are presented for the three TR orders
and optimal and sub-optimal λs. An optimal λ selection
shows dominant frequency maps with localized areas of
high frequencies (red-coloured) that match between the
three TR orders, moreover, areas of HDF match clearly
with SP in panel B, presenting interpretable results and
reproducible between orders. When a sub-optimal λ was
chosen HDF and SP are more dispersed in the presented Page 2 Figure 2. Results of the selected regularization parameters
(λ) for a high range of λ (dots) and low range (squares) for
zero, first and second order Tikhonov regularization (T0,
T1 and T2, respectively). Figure 3. AF-related metrics obtained with the three TR
orders versus the selected regularization parameters (λ) for
a high range (dots) and low range (squares) of λ. A:
Highest dominant frequency; B: rotors per second. Figure 2. Results of the selected regularization parameters
(λ) for a high range of λ (dots) and low range (squares) for
zero, first and second order Tikhonov regularization (T0,
T1 and T2, respectively). 3.2.
ECGI
metrics
vs.
regularization
parameter In Fig 3 ECGI derived metrics and how they change
between the studied ranges of the regularization parameter. are represented. Results of HDF (Fig 3A) appeared in the
range from 6 to 12 Hz for all the TR orders tested. Overall,
we did not find any relation between HDF and λ. The
number of rotors (Fig. 3B), in contrast, showed an inverse
relation with λ for the three TR methods tested. Figure 3. AF-related metrics obtained with the three TR
orders versus the selected regularization parameters (λ) for
a high range (dots) and low range (squares) of λ. A:
Highest dominant frequency; B: rotors per second. A comparative of the noninvasive metrics computed
from TR methods using both λ ranges is presented in Fig
4A. As it can be observed, T0 did not show differences in
the derived metrics based on λ ranges due to the lower
variability in parameter selection. However, differences
can be found in higher orders, that showed how lower λ
ranges are related to a higher complexity of the metrics,
being significantly higher for HDF (T2, p<0.05) and
specially in the number of rotors per second (p<0.01) that
showed higher mean values and standard deviations. In Fig
4B, the absolute difference between metrics and methods
is compared in both λ ranges. It is observed that this
variability is higher for the lower range, as well as its
dispersion. Highest dominant frequency differences were
significant only for the comparative between T0 and T2. Nevertheless, rotors per second showed statistical
difference for all the comparatives (p<0.01), being the
absolute difference between TR orders higher for the lower
regularization parameters. Figure 4. A. Comparison of ECGI metrics for each TR
order for a high range of λ (white) and a low range of λ
(blue). B. Comparison of the difference of ECGI derived
metrics between TR orders and λ ranges. Figure 4. A. Comparison of ECGI metrics for each TR
order for a high range of λ (white) and a low range of λ
(blue). B. Comparison of the difference of ECGI derived
metrics between TR orders and λ ranges. Page 3 Page 3 Page 3 4.
Discussion This work was supported by: Instituto de Salud Carlos
III, and Ministerio de Ciencia, Innovación y Universidades
(supported by FEDER Fondo Europeo de Desarrollo
Regional PI17/01106 and RYC2018-024346B-750), EIT
Health (Activity code 19600, EIT Health is supported by
EIT, a body of the European Union), Generalitat
Valenciana Grants (ACIF/2020/265) and PersonalizeAF
project, which received funding from the European
Union’s Horizon 2020 research and innovation programme
under the Marie Skłodowska-Curie grant agreement No
860974. This publication reflects only the author’s view
and the Agency is not responsible for any use that maybe
made of the information it contains. In this study we evaluated the relevance of the proper
range selection for the calculation of the regularization
parameter of the inverse problem in AF signals. Optimal
regularization parameters do cluster in quite narrow ranges
that are different for zero, first and second order Tikhonov
regularization. Selection of a smaller regularization
parameter than the optimal one does result in an increased
AF complexity that may not be related to the underlying
complexity. Tikhonov regularization methods, mostly zero-order,
have been preferred in the literature for ECGI resolution
during AF [4], which is consistent with our study, being
T0, the most consistent method in choosing the optimal λ
between ranges. First and second-order solutions, showed
larger λ variability, but results were more consistent for the
highest λ range. Although the epicardial signal
reconstruction could be oversmoothed for higher λs, T1
and T2 presented fewer differences between methods and
ECGI derived metrics, suggesting a more realistic
reconstruction. 5.
Conclusions ECGI derived metrics reflect higher complexity of AF
substrate when sub-optimal values of the regularization
parameter are selected for Tikhonov regularization and L-
curve optimization. Address for correspondence: A trade-off between regularization parameter range and
type of inverse problem method remains critical in
obtaining a good ECGI reconstruction, being the optimal
ranges for λ search different among T0, T1 and T2. Rubén Molero Alabau
ITACA. Edificio 8G acceso B. Universitat Politècnica de
València. Camino de Vera s/n. 46022 Valencia, Spain. rumoal1@itaca.upv.es Rubén Molero Alabau
ITACA. Edificio 8G acceso B. Universitat Politècnica de
València. Camino de Vera s/n. 46022 Valencia, Spain. rumoal1@itaca.upv.es Page 4 References [8] C. Fambuena et al., ''An Evaluation on the Potential Clinical
Outcome Prediction of Rotor Detection in Non-Invasive Phase
Maps',' Comput. Cardiol. Conf., 2021. (Unpublished). Address for correspondence: References [1]M. Rodrigo et al., “Non-Invasive Assessment of Complexity
of Atrial Fibrillation: Correlation with Contact Mapping and
Impact of Ablation”, Circ. Arrhythmia Electrophysiol., vol. 13,
No. 3, Feb. 2020. [2]J. Salinet et al., “Electrocardiographic Imaging for Atrial
Fibrillation: a Perspective from Computer Models and Animal
Experiments to Clinical Value”, Front. Physiol., 2021. (Accepted
for publication). ECGI obtained maps with lower λ ranges presented
higher HDF and rotors per second numbers, when
compared with higher λ values. Higher complexity of the
resulting metrics can be produced either for a realistic
ECGI approximation of a complex atria substrate or by
amplification of noise and small changes in the signal due
to the small regularization parameter, which is less likely
due to the found errors between TR orders and the
reconstructed DF and SP maps. Comparing the errors in
the metrics from different orders and λ ranges could
improve the quality of ECGI by choosing the λ that
minimizes the errors between methods, to avoid smooth
and noisy solutions. Therefore, we propose that the range
of lambda values to be searched for either zero, one or
second order Tikhonov regularization should be from 10-7
to 102. [3]C. Hansen, “Analysis of Discrete Ill-Posed Problems,” Soc. Ind. Appl. Math., vol. 34, no. 4, pp. 561–580, Dec. 1992. [4]C. Figuera et al., “Regularization Techniques for ECG
Imaging During Atrial Fibrillation: A Computational Study, ”,
Front. Physiol., vol. 7, no. Oct, 2016. [5]F. Castells, C. Mora, J. J. Rieta, D. Moratal-Pérez, and J. Millet, “Estimation of Atrial Fibrillatory Wave from Single-Lead
Atrial
Fibrillation
Electrocardiograms
Using
Principal
Component Analysis Concepts”, Med. Biol. Eng. Comput., vol. 43, no. 5, pp. 557–560, Oct. 2005. [6]P. C. Hansen and D. P. O’Leary, “The Use of the L-Curve in
the Regularization of Discrete Ill-Posed Problems”, SIAM J. Sci. Comput., vol. 14, no. 6, pp. 1487–1503, Nov. 1993. [7]M. Rodrigo et al., “Highest Dominant Frequency and Rotor
Postions are Robust Markers of Driver Location During
Noninvasive Mapping of Atrial Fibrillation: A Computational
Study”, Heart Rhythm, vol. 14, no. 8, pp. 1224-1233, Aug. 2017. [8] C. Fambuena et al., ''An Evaluation on the Potential Clinical
Outcome Prediction of Rotor Detection in Non-Invasive Phase
Maps',' Comput. Cardiol. Conf., 2021. (Unpublished). [7]M. Rodrigo et al., “Highest Dominant Frequency and Rotor
Postions are Robust Markers of Driver Location During
Noninvasive Mapping of Atrial Fibrillation: A Computational
Study”, Heart Rhythm, vol. 14, no. 8, pp. 1224-1233, Aug. 2017. Rubén Molero Alabau
ITACA. Edificio 8G acceso B. Universitat Politècnica de
València. Camino de Vera s/n. 46022 Valencia, Spain.
rumoal1@itaca.upv.es
|
https://openalex.org/W2755414273
|
https://bmcmededuc.biomedcentral.com/track/pdf/10.1186/s12909-017-1010-4
|
English
| null |
Implementation of a Smartphone application in medical education: a randomised trial (iSTART)
|
BMC medical education
| 2,017
|
cc-by
| 6,408
|
Martínez et al. BMC Medical Education (2017) 17:168
DOI 10.1186/s12909-017-1010-4 Martínez et al. BMC Medical Education (2017) 17:168
DOI 10.1186/s12909-017-1010-4 © The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. * Correspondence: felipe.martinez@uv.cl
1Departamento de Salud Pública, Escuela de Medicina, Universidad de
Valparaíso, Hontaneda, 2664 Valparaíso, Chile
2Área de Investigación y Estudios Clínicos, Clínica Ciudad del Mar, Viña del
Mar, Chile
Full list of author information is available at the end of the article Implementation of a Smartphone
application in medical education: a
randomised trial (iSTART) Felipe Martínez1,2*, Catalina Tobar3 and Carla Taramasco4 Felipe Martínez1,2*, Catalina Tobar3 and Carla Taramasco4 Abstract Background: Smartphones are popular technologies that combine telephone communications and informatics in
portable devices. Limited evidence exists regarding their effectiveness in improving academic performance among
medical students. This study aims to assess whether a smartphone application could improve academic performance
in multiple-choice tests. Methods: A double-masked randomised trial was held among interns at the School of Medicine of the Universidad de
Valparaiso. Participants were randomised to receive an application designed to review key concepts in Internal Medicine
and its subspecialties using clinical vignettes. Contents were selected and provided in a format akin to a mandatory
national examination required for practising medicine in Chile. Analyses were undertaken under the intention to treat
principle and missing data were handled using multiple imputation techniques. Results: Eighty interns volunteered to participate in this trial, most were female (48 students, 60%) and had a mean age
of 25.3 ± 2.2 years. Participants showed significant experience with smartphones, with a median use of 4 years (IQR
3–6 years) and 67 (83.7%) reporting routine use in clinical practice. Intention-to-treat analyses showed significant
improvements in performance amongst students allocated to the smartphone application (mean increase of 14.5 ± 8.9
vs 9.4 ± 11.6points, p = 0.03). A reduction in total time and mean time per question was also found, which was
significant in complete-case analyses (p = 0.04). Discussion: Smartphones were popular among medical trainees. Academic performance was significantly improved
by the use of our application, although the overall effect was smaller than expected from previous trials. This study
provides evidence that smartphone-based interventions can assist in teaching internal medicine. Trial registration: ClinicalTrials NCT02723136. Keywords: Medical education, Internal medicine, Smartphones, Student, medical range from undergraduate education to health resource
management [4, 5]. Several studies have shown that
smartphones are frequently used among physicians,
medical students and interns, with overall use rates
reaching 80%. iOs®-based systems, such as the iPhone®,
seem to be the most commonly used platforms [1, 6–8]. The popularity of smartphones is likely to stem from
their versatility. Current devices have a wide variety of
functions, which can assist in medical decision making,
information
searches
and
educational
applications,
among other uses [8]. Use in clinical practice seems to
be more common among women, people with an Interventions Students allocated to receive the active intervention re-
ceived a downloadable application that was installed in
their smartphones. Those allocated to the control group
did not receive any additional training for EUNACOM. The mobile application was devised by a team of infor-
matic engineers and physicians and made available for
free at the App Store® and PlayStore® for both iOs® and
Android® operating systems. In order to monitor adher-
ence, the application required an active internet connec-
tion for operation. Students also received a brief (5-min)
description on functionality that was also made available
in text form as a part of the software. This study aims to determine whether the implemen-
tation of a smartphone application designed to assist in
delivering key concepts relevant to internal medicine
might improve academic performance in EUNACOM. Contents were primarily directed at the area of In-
ternal Medicine, which is the most important specialty
within EUNACOM. It included a series of questions in
the form of brief clinical vignettes constructed in a
format similar to the one described in EUNACOM’s
website [15]. In short, these vignettes correspond to clin-
ical scenarios against which the student must answer a
key aspect relevant to the diagnosis, management or
monitoring of several diseases. These multiple-choice
questions must be answered from five possible options,
with only one being the correct answer. The depth of
knowledge required to answer was established using the Background Smartphones are recent technologies that combine the
capabilities of telephone communications and informat-
ics in small portable devices that allow communications
and information processing even at the patient’s bedside
[1, 2]. As noted in the general public, these devices have
shown significant growth in the international medical
community [3], niche where they perform functions that * Correspondence: felipe.martinez@uv.cl
1Departamento de Salud Pública, Escuela de Medicina, Universidad de
Valparaíso, Hontaneda, 2664 Valparaíso, Chile
2Área de Investigación y Estudios Clínicos, Clínica Ciudad del Mar, Viña del
Mar, Chile
Full list of author information is available at the end of the article Martínez et al. BMC Medical Education (2017) 17:168 Page 2 of 9 interest in new technologies and those with prior experi-
ences with these platforms [7]. non-pharmacological interventions [13, 14]. The complete
protocol was registered in March 2016 at clinicaltrials.gov
(NCT02723136) and can be reviewed at https://clinical-
trials.gov/ct2/show/NCT02723136?term=NCT02723136&r
ank=1. A flowchart describing participant recruitment and
overall study design is shown in Fig. 1. Despite this popularity, there is limited evidence
regarding the effectiveness of smartphone use in improv-
ing academic performance among medical students [9]. While there is a wide availability of applications and
resources available for these platforms, only a few rando-
mised trials have addressed their effectiveness in improv-
ing academic performance. In 2011, Low and coworkers
published one of these studies using objective clinical
competence scores as a primary endpoint [10]. The lat-
ter trial reported a statistically significant improvement
of roughly 15% in the academic performance of students
allocated to receive the application. Similar findings were
seen in a second, before & after, study that was con-
ducted among Obstetrics & Gynecology residents [11]. Participants Eligible participants were medical interns coursing their
last year of training at the School of Medicine of the
Universidad de Valparaiso, who had a personal Smart-
phone
with
an
iOs®-
or
Android®-based
operating
system. Only those that did not wish to participate were
excluded from this study. Informed consent was ob-
tained from all participants. Every student sat a baseline 90-question test aimed to
resemble EUNACOM (see below) and were randomised
to receive a smartphone-based application training after-
wards. Randomisation was carried out using permuted
blocks by a statistician that was unaware of treatment
allocation. Allocation sequences were concealed from
other researchers participating in this study. All partici-
pants were asked to complete an entry form with basic
demographic data, including age, sex, year of training
and prior experiences with smartphones or similar
platforms (i.e. tablets). Data regarding academic per-
formance was obtained from the University, including
qualifications relevant to the area of Internal Medicine. g
y
gy
Since 2003, a national examination for undergraduate
medical students that have completed their internships
is carried out in Chile. This exam (Examen Unico
Nacional de Conocimientos en Medicina - EUNACOM)
is designed to assess the overall knowledge and practical
skills that any medical student should attain before prac-
tising medicine in the country. Its confection and
administration are regulated by law, and its oversight
has been delegated to the Association of Faculties of
Medicine of Chile (ASOFAMECH). EUNACOM is made
of two sections, theoretical and practical, and is consid-
ered qualifying to practise medicine in Chile. The con-
tents of both sections are of public knowledge and
include 1543 items distributed according to the curricu-
lar time spent training in different areas of medicine,
with special emphasis on internal medicine and its sub-
specialties [12]. The theoretical component is evaluated
using 180 multiple-choice questions delivered in two
90-min
sessions. Additionally,
EUNACOM
provides
professional title validation or equivalencies for foreign
physicians who wish to practice medicine in Chile. Given
the importance of this exam, several medical schools have
implemented preparation courses for their students. How-
ever, the methodologies used in the latter courses are
heterogeneous, and uncertainty exists regarding the best
way in which contents should be delivered. Methods iSTART is a double-masked randomised trial that was
held among medical students at the School of Medicine
of the Universidad de Valparaíso, Chile. The study proto-
col has been drafted in compliance with the Consoli-
dated
Standards
of
Reporting
Trials
(CONSORT)
statement as in its version adapted for trials evaluating Martínez et al. BMC Medical Education (2017) 17:168 Page 3 of 9 Fig. 1 CONSORT Study Flowchart. This figure depicts participant’s flow within the iSTART study ig. 1 CONSORT Study Flowchart. This figure depicts participant’s flow within the iSTART study resemble EUNACOM between groups. The final test did
not repeat any of the questions used within the applica-
tion that was delivered to students and was held 4 weeks
after randomisation. This timeframe was selected in
order to allow students to practise and study internal
medicine with the application given the extent of
contents required by EUNACOM. Simulation tests were
used because of the impossibility to use the actual exam
as part of this study, since it is managed independently
from universities and kept in strict reserve by ASOFA-
MECH. However, previous data has shown that both
simulation exams (baseline and final) have good correl-
ation with overall EUNACOM scores (r > 0.7, p < 0.001),
as well as an excellent diagnostic accuracy for detecting
students at risk of failing the exam(area under the ROC
curve 0.95, 95% CI 0.90 to 0.99) and identifying students
that will obtain high scores in the review (AUC 0.80, 95%
CI 0.71 to 0.88, unpublished data). The correction of both
practice tests was undertaken by reseachers that were kept
unaware of allocation. provisions of the EUNACOM agenda [12]. All contents
of the application were designed by two internists with
5 years experience in developing questions for the exam. Examples
of
these
vignettes
are
provided
in
the
Additional file 1. The application had two modes to provide the afore-
mentioned inquiries. In the first, study mode, students
were not given time constraints to answer the clinical vi-
gnettes. Whenever an answer was provided, instant feed-
back was delivered alongside a brief explanation of the
key concept that was being assessed by the inquiry. In
the second, training mode, participants had a restricted
time window to provide answers. This mode was
designed because of a perceived difficulty amongst in-
terns in managing time in answering questions in previ-
ous simulations of the exam. Methods A default of 60 s was
established, but the application allowed the user to mod-
ify this timeframe to 30 or 90 s. Students had knowledge
regarding their individual performance in both modes,
but no additional feedback in terms of concept review
was provided in training mode. A secondary endpoint was to establish differences in
the average time required to answer clinical vignettes. In
order to allow reliable comparisons to be made, exams
were conducted electronically and under supervision by
the research team, thus allowing an objective assessment Analysis plan Basic descriptive statistics (means, medians, proportions,
interquartile ranges -IQR-, etc) were performed to assess
the characteristics of the study sample. Fisher’s exact test
was used to evaluate univariate association of categorical
variables. Quantitative variables were compared using
Mann-Whitney or Student’s T tests according to data
distribution and variances. Ninety-five percent confi-
dence intervals were constructed whenever appropriate. Missing data relevant to the primary and secondary out-
comes were handled using multiple imputation tech-
niques. In order to reduce sampling variability due to
the imputation process, 20 datasets were generated for
every variable with missing data. Predictor variables
were included in this procedure using linear regression
for data showing normal distributions. Predictive mean
matchings were preferred to impute data for variables
with skewed distributions. All analyses were undertaken
by a statistician who was unaware of participant alloca-
tion using Stata v12.0® (StataCorp LP, 1996–2016) under
the
intention-to-treat
principle,
but
complementary
complete-case
analyses
were
conducted
as
part
of
multiple imputation techniques. Intention to treat analyses using multiple imputation
techniques showed significant differences between study
groups. Missing scores were imputed using results from
the baseline test and allocation as independent variables
in linear regression analyses. On average, interns allocated
to the smartphone application had an increase in scores
that was 5 points (9%) higher than those observed in the
no-intervention group (p = 0.03). Similar trends were seen
when complete-case analyses were undertaken. When
overall scores were analysed, an absolute difference of 3.5
points was observed between groups in favour of those al-
located to the smartphone application, but statistical sig-
nificance was not reached (p = 0.22). Study outcomes are
briefly summarised in Table 2 and Fig. 2. Students
allocated
to
the
smartphone
application
showed reductions in the total time needed to complete
the final examination and the mean time spent per ques-
tion. Intention-to-treat analyses showed a nonsignificant
reduction of 8.5 min for the first outcome and 5.7 s for
the latter (p = 0.08 for both). This estimate was calculated
using predictive mean matching due to the skewed nature
of time data, using allocation and both baseline perform-
ance and time required to complete the first examination
as predictor variables. These differences were more
conservative than the ones observed in complete-case
analyses. Outcomes The primary outcome is the mean change in overall
scores
in
a
90-question
practise
test
designed
to Page 4 of 9 Martínez et al. BMC Medical Education (2017) 17:168 Martínez et al. BMC Medical Education (2017) 17:168 of the total time required to complete the review. Data
regarding adherence was also collected. of the total time required to complete the review. Data
regarding adherence was also collected. The most common operating system was Android® (51
students, 63.8%). No relevant imbalances in study groups
were seen at baseline. A detailed description of these
contrasts and additional information regarding study
participants is provided in Table 1. Analysis plan Among participants who attended the second as-
sessment, a 10-min reduction in overall time and a 6.7 s
reduction in mean time per question were found, and
both reached statistical significance (p = 0.04). Total times
spent by participants answering both baseline and final
questionnaires are shown in Fig. 3. Intervention effects The mean score in the baseline test was of 41.1 ± 11.1
points, and mean total time needed for completion of the
latter review was 65.6 ± 27.0 min. Scores and completion
times were similar between groups at baseline. Sixty-five
interns (81.3%) sat the final test 4 weeks after randomisa-
tion. In both groups, a significant increase in overall
scores was seen, which tended to be greater among interns
allocated to receive the smartphone application. Partici-
pants allocated to no intervention showed an increase of
10.6 ± 11.7 points (p < 0.001) from baseline, while interns
who received the smartphone application improved their
scores by 16.2 ± 8.3 points (p < 0.001). Participant characteristics A total of 80 interns were eligible for this study, and all
volunteered
to
participate. Most
were
female
(48
students, 60%) with a mean age of 25.3 ± 2.2 years and
had spent a median of 6 years in medical school (IQR
6–7 years). Eighteen (22.5%) had repeated at least one
course, and the median number of repetitions was 1
(IQR 1–3). The median time using smartphones was of
4 years (IQR 3–6 years). Most interns reported routine
use of smartphone applications in daily practice (67
students, 83.7%), but only a third of them acknowledged
using them for academic purposes (31 students, 38.8%). Statistical analyses
Sample size Sample size was calculated using data regarding overall
perfomance in prior experiences with practise exams
and estimates from a randomised trial [10]. It was calcu-
lated that a sample size of 64 participants (32 per group)
would be required to obtain 80% power to detect an
absolute difference of 5 points between groups, assum-
ing a standard deviation of 7 points for both groups at
standard significance levels (two-tailed α of 5%). In order
to correct for up to 20% losses of follow-up, it was
sought to randomise 75 participants. All estimates were
calculated using nQuery Advisor® 3.0 for windows. Adherence The median number of tests answered by these the intervention (85%, 95% CI 70.2–94.2%). The median
number of questions answered during the 4-week inter-
vention period was 258 (IQR 66–415), and the median
number of completed questionnaires per participant was
15 (IQR 14–21). Participants used the application’s train-
ing mode less frequently, with only 12 students (30%,
95%CI 16.6–46.5%) registering any activity during this
trial. The median number of tests answered by these Adherence The most popular mode amongst participants was study
mode, which was used by 34 participants allocated to Martínez et al. BMC Medical Education (2017) 17:168 Page 5 of 9 Table 1 Baseline Participant Characteristics
Characteristic
Smartphone Application (n = 40)
No Intervention (n = 40)
Total
P-Value
General and Academic characteristics
Mean Age (years) (SD)
25.6 ± 2.7
24.9 ± 1.5
25.3 ± 2.2
0.181
Female sex (n, %)
27 (67.5%)
21 (52.5%)
48 (60%)
0.252
Median time in medical school (years) (IQR)
6 (6–7)
6 (6–7)
6 (6–7)
0.351
Campus Valparaiso (n, %)
28 (70%)
28 (70%)
56 (70%)
12
Course repetition (n, %)
10 (25%)
8 (20%)
18 (22.5%)
0.791
Median number repetitions (IQR)
1.5 (1–3)
1 (1–3)
1 (1–3)
0.263
Internal Medicine Internship Grade (SD)
6.3 ± 0.4
6.3 ± 0.4
6.3 ± 0.4
0.841
Internal Medicine Undergraduate Examination
Grade (SD)
5.4 ± 0.7
5.4 ± 0.7
5.4 ± 0.8
0.911
Experience with Smartphones
Median time using smartphones (years) (IQR)
4 (3–5)
4 (3–6)
4 (3–6)
0.891
Smartphone use in clinical practice (n, %)
34 (85%)
33 (82.5%)
67 (83.7%)
12
Smartphone use for academic purposes (n, %)
16 (40%)
15 (37.5%)
31 (38.8%)
12
Operating system (n, %)
Android®
25 (62.5%)
26 (65%)
51 (63.8%)
12
iOs®
15 (37.5%)
14 (35%)
29 (36.2%)
Performance in Baseline Test
Mean overall score (SD)
40.3 ± 11.0
41.8 ± 11.2
41.1 ± 11.1
0.531
Mean total time (minutes) (SD)
65.2 ± 26.3
66.0 ± 28.0
65.6 ± 27.0
0.891
Mean time per question (seconds) (SD)
44.3 ± 18.6
45.5 ± 21.7
44.9 ± 20.1
0.801
1Student’s T Test. 2Fisher’s Exact Test3Mann-Whitney U TestSD: Standard Deviation. IQR: Interquartile range Student’s T Test. 2Fisher’s Exact Test3Mann-Whitney U TestSD: Standard Deviation. IQR: Interquartile range dent’s T Test. 2Fisher’s Exact Test3Mann-Whitney U TestSD: Standard students was 2 (IQR 1–4), which translated in 90 (IQR
45–180) time-limited questions (Table 3). students was 2 (IQR 1–4), which translated in 90 (IQR
45–180) time-limited questions (Table 3). the intervention (85%, 95% CI 70.2–94.2%). The median
number of questions answered during the 4-week inter-
vention period was 258 (IQR 66–415), and the median
number of completed questionnaires per participant was
15 (IQR 14–21). Participants used the application’s train-
ing mode less frequently, with only 12 students (30%,
95%CI 16.6–46.5%) registering any activity during this
trial. Discussion Thirty-one physicians who had
already completed an advanced life support course within
the previous 4 years were randomised to receive iResus® as
a cognitive aid or no additional support during a simu-
lated cardiac emergency. Performance was measured
using a validated scoring system. Participants allocated to
iResus® showed median scores that were 12.5 (14%) points
higher than those seem among students without any fur-
ther cognitive aids (p = 0.02). Similar findings were seen
in a larger study by Hand an coworkers [16], in which 111
residents
were
randomised
to
a
smartphone-based
decision support tool aimed at improving adherence to
the American Heart Association Guidelines on Periopera-
tive Cardiac Evaluation. Use of the decision support tool
resulted in a 25% improvement in adherence to guidelines
(p < 0.001), and participants made 77% fewer incorrect re-
sponses in two standardised tests. everyday lives. This popularity makes these platforms
attractive targets to design and develop interventions for
medical training. However, only a handful of randomised
trials that address smartphone applications with educational
purposes are available in the literature. Most of them
have been conducted among postgraduate students
undergoing specialty training, and used smartphones
as cognitive aids concomitant to assessments of very
specific competences [10, 16, 17]. We found that the provision of key concepts in internal
medicine using smartphones was a feasible option that
also translated in significant improvements in academic
performance
among
medical
interns. The
observed
progress was significant even for a relatively brief inter-
vention that was also self-administered by our students,
which adds to the relevance of our findings. Our results
are in concordance with the ones observed in similar Fig. 3 Total time spent per questionnaire. These boxplots show the
changes in time required to complete the simulation tests used within
iSTART between study groups Although our findings are similar to the ones seen in
the aforementioned trials, our estimates are far more
conservative than the ones observed by Low [10] and
Hand [16]. This might be explained by the fact that our
intervention was not devised to be used concomitantly
to assessments as a cognitive aid, but rather as a
complementary resource to facilitate study of internal
medicine as a discipline. Discussion Smartphones are commonly used devices among med-
ical trainees. In this study, every eligible student had at
least one of these gadgets at their disposal, and most
reported considerable experience using them in their Table 2 Study Outcomes
Outcome
Smartphone Application
No Intervention
Mean Difference
P-Value
Intention to Treat Analyses (Multiple Imputation)
Mean overall score (points) (SD)
56.1 ± 14.5
52.2 ± 10.3
3.5
0.221
Absolute change in overall score (points) (SD)
14.5 ± 8.9
9.4 ± 11.6
5.0
0.031
Mean total time (minutes) (SD)
62.2 ± 20.4
70.8 ± 21.3
8.5
0.082
Mean time per question (seconds) (SD)
41.2 ± 14.5
46.9 ± 13.6
5.7
0.082
Complete-Case Analyses
Mean overall score (points) (SD)
56.1 ± 12.9
52.2 ± 9.4
3.9
0.172
Absolute change in overall score (points) (SD)
14.6 ± 7.4
9.6 ± 10.5
5.0
0.032
Mean total time (minutes) (SD)
61.5 ± 19.7
71.5 ± 18.7
10.0
0.042
Mean time per question (seconds) (SD)
41.0 ± 13.2
47.7 ± 12.5
6.7
0.042
SD Standard Deviation
1Estimates obtained by pooling results across 20 multiply imputed data sets
2Student’s T Test Martínez et al. BMC Medical Education (2017) 17:168 Page 6 of 9 Table 3 iSTART adherence rates
Endpoint
Smartphone
Application
95% Confidence
Interval
Study Mode
Proportion of students using
this mode (n, %)
34 (85%)
70.2–94.2%
Median number of questions
answered (IQR)
258 (66–415)
96–376
Median number of questionnaires
completed (IQR)
15 (14–21)
13–22
Training Mode
Proportion of students using
this mode (n, %)
12 (30%)
16.6–46.5%
Median number of questionnaires
answered (IQR)
2 (1–4)
1–5
IQR Interquartile range Table 3 iSTART adherence rates Fig. 2 Absolute change in scores between study groups. These
boxplots compare the observed differences in perfomance in two
simulation tests aimed to resemble EUNACOM Fig. 2 Absolute change in scores between study groups. These
boxplots compare the observed differences in perfomance in two
simulation tests aimed to resemble EUNACOM experiences. In 2011, Low and coworkers [10] published a
randomised trial assessing iResus®, an iOs®-based applica-
tion aimed at improving performance of an advanced life
support provider in an emulated medical emergency. The
application was designed to provide a quick reference to
algorithms and drug dosages to assist in the management
of resuscitation efforts. Strengths and limitations Our study is strengthened by randomisation, which
greatly helps controlling biases due to selection and con-
founding. Contents within the application were designed
by internists with experience in developing questions
that resemble those used in EUNACOM. Previous data
available at our centre had shown good correlations with
overall scores and those specific with internal medicine
within the review, which has translated in excellent diag-
nostic accuracy in detecting students at risk of failing
the examination. We also conducted active monitoring
of the application’s use, which greatly helps understand-
ing our results and represents a key element when
evaluating
interventions
that
are
self-delivered
by
students. These data are likely to be helpful for the de-
sign of future versions or similar applications. g
pp
Several limitations need to be taken into consideration
when analysing our results. The first is that a significant
proportion of students did not attend the final examin-
ation (18.7%), which resulted in the loss of key informa-
tion regarding study outcomes. We chose to mitigate this
event by using multiple imputation techniques, which
have been established as one of the best methods available
to handle missing data in randomised trials [18, 19]. Uncertainty always exists when estimates from multiple
imputation are used to allow the conduction of intention-
to-treat analyses. This stems from the fact that the “miss-
ing completely at random” assumption of missing data is
hard to confirm in practice [18]. We did not find any
contrasts between participants who completed our study
and those who did not, and estimates from complete case
analyses were very similar to the ones obtained from mul-
tiple imputation. Both facts bring reassurance regarding
the reliability of our imputed values. Another limitation
stems from the impossibility to mask participants to the
intervention, which could have resulted in the applica-
tion’s contents being shared across study groups. This
would result in a minimisation of the intervention’s effects
between groups, and thus might explain the smaller-than-
expected difference that was found in this trial. Costs are
always a relevant concern when implementing interven-
tions in medical education. In this case, an investment of
50.000USD was required to develop the application and
its key contents, which was covered entirely by the
research team. Most expenses were incurred in human
resource honoraria. Discussion In addition, it should be
considered that the scope of contents established as
key by the designers of EUNACOM is broader than
the
ones
required
by
guidelines
aimed
at
aiding
clinicians in the management of specific healthcare is-
sues; thus resulting in an apparent reduction of the
intervention’s benefits. Fig. 3 Total time spent per questionnaire. These boxplots show the
changes in time required to complete the simulation tests used within
iSTART between study groups Page 7 of 9 Martínez et al. BMC Medical Education (2017) 17:168 Intention-to-treat analyses also showed a nonsignifi-
cant trend towards a reduction in total test times and
mean time spent per inquiry. A post-hoc power calcula-
tion showed that the estimated power for this contrast
was of only 45%, thus making insufficient power a rea-
sonable possibility to explain this observed lack of statis-
tical significance. Nonetheless, the observed reduction of
8.5 min is relevant for interns planning to undertake
EUNACOM, and is likely to be the result of practice in
answering multiple-choice questions. Clinical vignettes
are constructed using certain features that are typical of
certain conditions, thus leading to patterns that students
exposed to the application might have been able to recog-
nise faster than those allocated to the no-intervention
group. It could also be argued that students allocated to
the intervention also had more experience answering
questions on an electronic platform, thus resulting in
familiarity with the interface that might have explained
these findings. However, this explanation seems rather
unlikely considering the vast experience with smartphone
applications that participants had in this study. their strategies. Exploring motivations to use these types
of applications should be considered in future qualitative
research. Strengths and limitations Although this might be seen as a sig-
nificant barrier to implementation, it should be considered
that after this initial investment, the application was inex-
pensive to maintain, only requiring monthly payments for
a
server
and
a
part-time
engineer
to
oversee
its Given that the intervention was devised to be self-
administered by students, adherence was a key aspect to
assess while conducting our study. Thirty-four out of 40
participants (85%) used the application’s study mode to
review internal medicine in this trial, which was very sat-
isfactory. Furthermore, the median number of questions
and questionnaires completed was more than adequate
considering the relatively brief timeframe in which this
study was conducted. Only a minority of students allo-
cated to the intervention (12 students, 30%) used the ap-
plications’ training mode, the sole feature within the
application in which a time restraint to respond clinical
vignettes was applied. This obvious contrast in use rates
reached statistical significance (p < 0.001), and might be
explained by performance pressure. It is possible that in-
terns
felt
discouraged
to
undertake
activities
that
recorded results in a manner similar than the one used
in the actual EUNACOM. Participants could have asso-
ciated underperforming in these exercises with a poten-
tial for poor results in the exam, thus leading to the
observed use rates. Feedback provided by this mode did
not include a revision of the key concept in internal
medicine that was being assessed, thus possibly making
pressure
for
delivering
high
scores
more
tangible. Furthermore, interns were warned that time-limited ex-
ercises were accessible only once during our trial, which
might have led to lesser use rates in order to save this
component
of
the
application
after
the
reviewable
contents (study mode) were completed. Given these ex-
planations and the fact that EUNACOM applies a time
limit of 60 s per question, future interventions aimed at
improving performance in this and/or similar tests
should not disregard applying time restraints as part of Page 8 of 9 Page 8 of 9 Page 8 of 9 Martínez et al. BMC Medical Education (2017) 17:168 Martínez et al. BMC Medical Education (2017) 17:168 Martínez et al. BMC Medical Education (2017) 17:168 Page 8 of 9 functionality and data collection processes. Strengths and limitations Develop-
ment costs can be mitigated by working with volunteers
or in collaboration with other institutions or academic
departments which might use this application as a plat-
form for additional contents. The modular design of our
application allows unrestricted upload of questionnaires
that are not limited to undergraduate training, thus open-
ing a potential for postgraduate and continuous medical
education. In addition, institutions interested in imple-
menting
these
kind
of
applications
might
consider
allowing access to individuals by paying download/sub-
scription fees in order to ensure sustainability over time. Conclusion In summary, this randomised trial showed that the
provision of a smartphone application designed to emu-
late EUNACOM was successfully implemented amongst
medical interns. Its use was associated with significant
improvements in academic performance, and is likely to
be chiefly explained by the direct provision of concepts
in Internal Medicine in form of clinical vignettes. The
observed high adherence rates amongst interns make
these kinds of interventions a promising field to develop
in the future of medical education. 2. Mosa ASM, Yoo I, Sheets L. A systematic review of healthcare applications
for smartphones. BMC Med Inform Decis Mak. 2012;12(1):67. 3. Baumgart DC. Smartphones in clinical practice, medical education, and
research. Arch Intern Med. 2011;171(14):1294–6. 4. Free C, Phillips G, Watson L, Galli L, Felix L, Edwards P, et al. The
effectiveness of mobile-health technologies to improve health care service
delivery processes: a systematic review and meta-analysis. PLoS Med. 2013;10(1):e1001363. 5. Wheeler S, Tavares C, Jones R. How smartphones are changing the face of
mobile and participatory healthcare: an overview, with example from
eCAALYX. Biomed Eng. 2011;10:24. 1-14 6. Shah J, Haq U, Bashir A, Shah SA. Awareness of academic use of
smartphones and medical apps among medical students in a private
medical college? J Pak Med Assoc. 2016;66(2):184–6. Author details
1 1Departamento de Salud Pública, Escuela de Medicina, Universidad de
Valparaíso, Hontaneda, 2664 Valparaíso, Chile. 2Área de Investigación y
Estudios Clínicos, Clínica Ciudad del Mar, Viña del Mar, Chile. 3Departamento
de Medicina Interna, Hospital Gustavo Fricke, Álvares, 1532 Viña del Mar,
Chile. 4Laboratorio de Información y Tecnología, Escuela de Ingeniería
Informática, Universidad de Valparaíso, General Cruz, 222 Valparaíso, Chile. Received: 23 August 2016 Accepted: 13 September 2017 Received: 23 August 2016 Accepted: 13 September 2017 Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations. References
1
O'C 1. O'Connor P, Byrne D, Butt M, Offiah G, Lydon S, Mc Inerney K, et al. Interns
and their smartphones: use for clinical practice. Postgrad Med J. 2014;90(1060):75–9. 1. O'Connor P, Byrne D, Butt M, Offiah G, Lydon S, Mc Inerney K, et al. Interns
and their smartphones: use for clinical practice. Postgrad Med J. 2014;90(1060):75–9. Funding 11. Alipour S, Moini A, Jafari-Adli S. Comparison of teaching about breast
cancer via mobile or traditional learning methods in gynecology residents. Asian Pac J. 2012;13(9):4593–5. 11. Alipour S, Moini A, Jafari-Adli S. Comparison of teaching about breast
cancer via mobile or traditional learning methods in gynecology residents. Asian Pac J. 2012;13(9):4593–5. This study did not receive any funding. Availability of data and materials 12. Asociación de Facultades de Medicina de Chile. [Distribution of Questions
in EUNACOM - ST.] Available at: http://www.eunacom.cl/contenidos/
distribucion.html 12. Asociación de Facultades de Medicina de Chile. [Distribution of Questions
in EUNACOM - ST.] Available at: http://www.eunacom.cl/contenidos/
distribucion.html The datasets used and/or analysed during the current study available from
the corresponding author on reasonable request. 13. Boutron I, Moher D, Altman DG, Schulz KF, Ravaud P, CONSORT Group. Methods and processes of the CONSORT Group: example of an extension
for trials assessing nonpharmacologic treatments. Ann Intern Med. 2008;
148(4):W60-6. Authors’ contributions FM designed the study and application contents, conducted statistical analyses
and drafted the manuscript. CTB designed the application’s contents and reviewed
the final version of the manuscript to be published. CTT devised the smartphone
application, acquired the data and reviewed the manuscript prior to publication. All authors approved the final version of the manuscript to be published. 14. Moher D, Hopewell S, Schulz KF, Montori V, Gøtzsche PC, Devereaux PJ, et
al. CONSORT 2010 explanation and elaboration: updated guidelines for
reporting parallel group randomised trials. BMJ. 2010;340:c869. 15. Asociación de Facultades de Medicina de Chile. [Contents of the Examen
Único Nacional de Conocimientos de Medicina (EUNACOM)] Available At
en: http://www.eunacom.cl/contenidos/contenidos.html Additional file 1: Examples to Clinical Vignettes. (DOCX 112 kb) 8. Boruff JT, Storie D. Mobile devices in medicine: a survey of how medical
students, residents, and faculty use smartphones and other mobile devices
to find information. J Med Libr Assoc. 2014;102(1):22–30. Consent for publication
Not applicable. 17. McEvoy MD, Hand WR, Stiegler MP, DiLorenzo AN, Ehrenfeld JM, Moran KR,
et al. A Smartphone-based decision support tool improves test performance
concerning application of the guidelines for managing regional anesthesia Ethics approval and consent to participate The Review Board of the Universidad de Valparaiso reviewed and approved
the conduction of this study. Its registration number is CEC098–16. Informed
consent was obtained from every included participant. 16. Hand WR, Bridges KH, Stiegler MP, Schell RM, DiLorenzo AN, Ehrenfeld
JM, et al. Effect of a cognitive aid on adherence to perioperative
assessment and management guidelines for the cardiac evaluation of
noncardiac surgical patients. Anesthesiology. 2014;120(6):1339–49. quiz1349–53 Abbreviations
ASOFAMECH A ASOFAMECH: Asociación de Facultades de Medicina de Chile; CI: Confidence
Interval; EUNACOM: Examen Unico Nacional de Conocimientos en Medicina;
IQR: Interquartile Range; iSTART: Implementation of a Smartphone Application
in Medical Education: A Randomised Trial 9. Short SS, Lin AC, Merianos DJ, Burke RV, Upperman JS. Smartphones,
trainees, and mobile education: implications for graduate medical
education. J Grad Med Educ. 2014;6(2):199–202. 9. Short SS, Lin AC, Merianos DJ, Burke RV, Upperman JS. Smartphones,
trainees, and mobile education: implications for graduate medical
education. J Grad Med Educ. 2014;6(2):199–202. 10. Low D, Clark N, Soar J, Padkin A, Stoneham A, Perkins GD, et al. A
randomised control trial to determine if use of the iResus© application
on a smart phone improves the performance of an advanced life
support provider in a simulated medical emergency. Anaesthesia. 2011;66(4):255–62. Additional file 7. Sandholzer M, Deutsch T, Frese T, Winter A. Predictors of students’ self-
reported adoption of a smartphone application for medical education in
general practice. BMC Med Educ. 2015;15(1):91. Additional file 1: Examples to Clinical Vignettes. (DOCX 112 kb) Martínez et al. BMC Medical Education (2017) 17:168 in the patient receiving antithrombotic or thrombolytic therapy.
Anesthesiology. 2016 Jan;124(1):186–98.
18.
Sterne JAC, White IR, Carlin JB, Spratt M, Royston P, Kenward MG, et al.
Multiple imputation for missing data in epidemiological and clinical
research: potential and pitfalls. BMJ. 2009;338:b2393.
19.
Ware JH, Harrington D, Hunter DJ, D'Agostino RB. Missing data. N Engl
J Med. 2012;367:1353–4. Competing interests The authors declare that they have no competing interests. Page 9 of 9 Martínez et al. BMC Medical Education (2017) 17:168 in the patient receiving antithrombotic or thrombolytic therapy. Anesthesiology. 2016 Jan;124(1):186–98. 18. Sterne JAC, White IR, Carlin JB, Spratt M, Royston P, Kenward MG, et al. Multiple imputation for missing data in epidemiological and clinical
research: potential and pitfalls. BMJ. 2009;338:b2393. 19. Ware JH, Harrington D, Hunter DJ, D'Agostino RB. Missing data. N Engl
J Med. 2012;367:1353–4. • We accept pre-submission inquiries
• Our selector tool helps you to find the most relevant journal
• We provide round the clock customer support
• Convenient online submission
• Thorough peer review
• Inclusion in PubMed and all major indexing services
• Maximum visibility for your research
Submit your manuscript at
www.biomedcentral.com/submit
Submit your next manuscript to BioMed Central
and we will help you at every step: • We accept pre-submission inquiries
• Our selector tool helps you to find the most relevant journal
• We provide round the clock customer support
• Convenient online submission
• Thorough peer review
• Inclusion in PubMed and all major indexing services
• Maximum visibility for your research
Submit your manuscript at
www.biomedcentral.com/submit
Submit your next manuscript to BioMed Central
and we will help you at every step: • We accept pre-submission inquiries
• Our selector tool helps you to find the most relevant journal
• We provide round the clock customer support
• Convenient online submission
• Thorough peer review
• Inclusion in PubMed and all major indexing services
• Maximum visibility for your research
Submit your manuscript at
www.biomedcentral.com/submit
Submit your next manuscript to BioMed Central
and we will help you at every step: Submit your next manuscript to BioMed Central
and we will help you at every step:
|
https://openalex.org/W2041835455
|
https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0011425&type=printable
|
English
| null |
MER41 Repeat Sequences Contain Inducible STAT1 Binding Sites
|
PloS one
| 2,010
|
cc-by
| 11,173
|
Christoph D. Schmid1,2,3*, Philipp Bucher1 1 Swiss Institute of Bioinformatics, EPFL (E´cole Polytechnique Fe´de´rale de Lausanne) SV ISREC (The Swiss Institute for Experimental Cancer Research) GR-BUCHER,
Lausanne, Switzerland, 2 Swiss Tropical and Public Health Institute (Swiss TPH), Basel, Switzerland, 3 University of Basel, Basel, Switzerland Abstract This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This work was done with support from the Swiss Government (direct funding to the Swiss Institute of Bioinformatics). The funders had no role in study
design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. Competing Interests: The authors have declared that no competing interests exist. * E-mail: Christoph.Schmid@unibas.ch Abstract Chromatin immunoprecipitation combined with massively parallel sequencing methods (ChIP-seq) is becoming the
standard approach to study interactions of transcription factors (TF) with genomic sequences. At the example of public
STAT1 ChIP-seq data sets, we present novel approaches for the interpretation of ChIP-seq data. We compare recently
developed approaches to determine STAT1 binding sites from ChIP-seq data. Assessing the content of the established
consensus sequence for STAT1 binding sites, we find that the usage of ‘‘negative control’’ ChIP-seq data fails to provide
substantial advantages. We derive a single refined probabilistic model of STAT1 binding sequences from these ChIP-seq
data. Contrary to previous claims, we find no evidence that STAT1 binds to multiple distinct motifs upon interferon-gamma
stimulation in vivo. While a large majority of genomic sites with high ChIP-seq signal is associated with a nucleotide
sequence ressembling a STAT1 binding site, only a very small subset of the over 5 million potential STAT1 binding sites in
the human genome is covered by ChIP-seq data. Furthermore a surprisingly large fraction of the ChIP-seq signal (5%) is
absorbed by a small family of repetitive sequences (MER41). The observation of the binding of activated STAT1 protein to a
specific repetitive element bolsters similar reports concerning p53 and other TFs, and strengthens the notion of an
involvement of repeats in gene regulation. Incidentally MER41 are specific to primates, consequently, regulatory
mechanisms in the IFN-STAT pathway might fundamentally differ between primates and rodents. On a methodological
aspect, the presence of large numbers of nearly identical binding sites in repetitive sequences may lead to wrong
conclusions about intrinsic binding preferences of TF as illustrated by the spacing analysis STAT1 tandem motifs. Therefore,
ChIP-seq data should be analyzed independently within repetitive and non-repetitive sequences. Citation: Schmid CD, Bucher P (2010) MER41 Repeat Sequences Contain Inducible STAT1 Binding Sites. PLoS ONE 5(7): e11425. doi:10. Citation: Schmid CD, Bucher P (2010) MER41 Repeat Sequences Contain Inducible STAT1 Binding Sites. PLoS ONE 5(7): e11425. doi:10.1371/journal.pone.0011425
Editor: Guillaume Bourque, Genome Institute of Singapore, Singapore
i
d
b
d
bli h d
l Received December 18, 2009; Accepted June 2, 2010; Published July 6, 2010 Received December 18, 2009; Accepted June 2, 2010; Published July 6, 2010 Copyright: 2010 Schmid, Bucher. MER41 Repeat Sequences Contain Inducible STAT1
Binding Sites Christoph D. Schmid1,2,3*, Philipp Bucher1 PLoS ONE | www.plosone.org Introduction Early studies on PLoS ONE | www.plosone.org 1 July 2010 | Volume 5 | Issue 7 | e11425 STAT1 on MER41 relatively few binding sequences defined a consensus sequence
TCCNNNGAA of the IFN-c-activated site (GAS [13]). Subse-
quent
studies
established
a
descriptor
of
STAT1
binding
preferences with an improved specificity by defining a position-
specific weight matrix (PWM) derived from the in vitro binding of
STAT1 to synthetic oligonucleotides [14]. Described alternative
STAT1 binding sites include the ISRE motif [15] and an
additional variant of the GAS motif (M2, [7]). applying peak detection with identical parameters on the control
ChIP-seq data set derived from unstimulated HeLa cells. 286
(80%) of these ‘unstimulated sites’ are located within +/- 100bp to
a corresponding peak in the stimulated set. relatively few binding sequences defined a consensus sequence
TCCNNNGAA of the IFN-c-activated site (GAS [13]). Subse-
quent
studies
established
a
descriptor
of
STAT1
binding
preferences with an improved specificity by defining a position-
specific weight matrix (PWM) derived from the in vitro binding of
STAT1 to synthetic oligonucleotides [14]. Described alternative
STAT1 binding sites include the ISRE motif [15] and an
additional variant of the GAS motif (M2, [7]). p
g p
Next, we aim to compare the results of our peak detection
approach to previously described STAT1 sites (or center positions
of ‘binding regions’) derived from the identical ChIP-seq data set
[3,7] and to an additional independent STAT1 ChIP-seq data set
[12]. The consensus sequence TCCNNNGAA of the IFN-c-
activated site (GAS [13]) does not comprehensively describe all
binding sequences of STAT1, but it allows an unbiased assessment
of the positional precision of the determination of STAT1 binding
in sequence sets. The original analysis of the ChIP-seq data set [3]
produced 41582 binding regions with an average size of about
1kb. In our approach the concentration of the counts of ChIP-seq
reads at the putative center position of IP fragments considerably
enhances the precision and the sensitivity in the detection of sites
with high ChIP-seq signal (peaks). We sort the sets of STAT1
binding sites by decreasing confidence levels either according to
the coverage by ChIP-seq reads or according to statistical scores
provided by the analysis [12]. Comparing equally sized samples of
all sets, a significant increase in the average content of GAS
consensus sequences precisely at the position of the inferred
STAT1 binding sites is consistently observed for all sets (Fig. Introduction protein in the specific cell population [3]. The enhanced precision
in the large-scale mapping of binding sites occupied in vivo might
also overcome some of the limitations of descriptors of binding
sites based on conventional ChIP-chip approaches. The precise spatial and temporal regulation of gene expression
remains poorly understood despite an increasing number of
species with nearly complete genome sequences available. Proteins
which regulate the expression of genes by binding to specific DNA
sequences in the vicinity of their targets have been termed
transcription factors (TFs). The nucleotide sequences of observed
binding sites generally display a considerable variation, which may
cause difficulties in the description of binding preferences using
sequence motifs. Recent benchmarking studies confirmed that
transcription factor binding sites (TFBS) prediction based on
statistical motif discovery approaches is unreliable and thus
remains a major bottleneck in the study of transcriptional
regulatory regions [1,2]. Identification of regulatory elements
based on evolutionary conservation, also known as phylogenetic
footprinting, has the evident drawback of missing regulatory
elements responsible for diversity among species. Therefore
laboratory experiments assaying DNA-protein interactions in vivo
remain indispensable. Especially massively parallel sequencing
technologies in combination with chromatin immunoprecipitation
(ChIP-seq) has proven a very powerful method to locate precisely
the DNA elements that physically interact with the targeted Methods for interpreting ChIP-seq data are currently under
intensive development. A common aspect of emerging solutions
includes the possibility to recognize and process separately
sequence reads from the + and the 2 strand of pulled down
fragments [4]. The exact mapping of the ChIP fragment ends
allows consequently for more accurate delineation of DNA regions
that interact with the targeted protein. The other main task in the
analysis of ChIP-seq data consists in the separation of ‘true signal’
from spurious background associated with ChIP or additional still
uncharacterized experimental artifacts. Various approaches of
‘peak calling’ have been applied to determine loci with a clearly
increased coverage of ChIP-seq reads. Some of these methods
include complex statistical approaches and data from ‘negative
control’ experiments [5,6,7,8,9,10,11,12]. STAT1 is a member of an intensively studied family of TFs with
implications in the regulation of immune responses. In resting cells
STAT1 is mainly located in the cytosol. Upon stimulation with the
cytokine interferon gamma (IFN-c), STAT1 is trans-located to the
nucleus to bind to target DNA sequences. Introduction 1,
background content at distant positions ,5%). For the 3000 top
ranking sites, our ChIP-peak set stands out with the highest and
best focused enrichment featuring a GAS within 100bp of almost
50% of the inferred sites. This frequency exceeds that of 37
STAT1 binding sites collected from descriptions in the literature
[22]. This apparent discrepancy is most likely explained by a
considerable fraction of sites with an alternative STAT1 binding
motif (ISRE [15]) in the literature set, while ISRE is not detected
in any of the ChIP-seq derived sets (Fig. 1). In the comparison in
Fig. 1 the set by Jothi et al. closely follows our set and the
algorithm by Rozowsky et al. catches up in the larger sets of 30000
highest ranking sites. These larger sets include also lower affinity
sites and accordingly display a lower frequency of ‘perfect’ GAS
without mismatches. At least for sites with moderate to high ChIP-
seq coverage, the inclusion of information from ‘control’ ChIP-seq
data sets in the peak calling [7,12] (e.g. DNA from unstimulated Repetitive sequence elements constitute almost half of the
human genome, however their potential functions are still poorly
defined. A number of recent studies either predict TFBS within
repeat sequences [16,17], or present evidence for an interaction of
regulatory proteins with repeats [18,19,20,21]. In addition to an
enhanced positional resolution, ChIP-seq is more effective in
mapping DNA-protein complexes located inside repetitive ele-
ments, where the ChIP-chip approach faces serious limitations due
to cross-hybridization. The present re-analysis of ChIP-seq data extends the analysis of
STAT1 binding for the first time to repetitive sequences. We
furthermore show that ChIP-Seq data can be used to analyze the
relation of in vivo interactions and extended sequence features
such as spacing within regulatory modules of binding sites. A large
number
of
virtually
identical
binding
sites
within
repeats
potentially induces a strong bias in a corresponding binding site
model and could lead to wrong conclusions regarding preferential
associations and constraints in distances to other TFBS. We
present therefore approaches to analyze ChIP-seq data which also
take into account the emerging roles of repeats in the regulation of
gene expression and evolutionary aspects. All results shown in this
article are based on public ChIP-Seq data described in [3] defining
the genome-wide distribution of STAT1 protein in HeLa cells
upon c-interferon stimulation. ChIP-peak calling and comparison to other algorithms
ChIP
k (
h d ) d fi
f 4446 STAT1 bi di ChIP-peak calling and comparison to other algorithms
ChIP-peak (see methods), defines a set of 4446 STAT1 binding
sites highly occupied in IFN-c-stimulated HeLa cells (list as Files
S1 and S2). In accordance with limited amounts of STAT1 in the
nucleus of unstimulated cells [13], we obtain only 356 sites if Figure 1. Content of binding sites to assess STAT1 ChIP-seq sets. The frequencies of binding sequences TCCNNNGAA in 4 sets of genomic
loci derived from STAT1 ChIP-seq data. ‘ChIP_peak’ contains STAT1 sites as defined in this study, FindPeaks (Robertson et al.), SISSR (Jothi et al.), and
MACS (Zhang et al.) are derived of analyses of the identical ChIP-seq data set and PeakSeq (Rozowski et al.) uses an independent STAT1 ChIP-seq data
set. The sets contain the top 3000 (left panel) or top 30 000 sites (center & right panel) of the corresponding data. The literature set consists of 37
STAT1 sites collected in the ORegAnno database. The occurrence of GAS is assessed in 100 bp sequence windows (SSA web server http://www.isrec. isb-sib.ch/ssa/). Plotted points represent the center positions of windows relative to the position of the putative STAT1 site predicted from ChIP-seq
data. The right panel displays the frequency of the ISRE PWM (Transfac entry M00258). doi:10.1371/journal.pone.0011425.g001 Figure 1. Content of binding sites to assess STAT1 ChIP-seq sets. The frequencies of binding sequences TCCNNNGAA in 4 sets of genomic
loci derived from STAT1 ChIP-seq data. ‘ChIP_peak’ contains STAT1 sites as defined in this study, FindPeaks (Robertson et al.), SISSR (Jothi et al.), and
MACS (Zhang et al.) are derived of analyses of the identical ChIP-seq data set and PeakSeq (Rozowski et al.) uses an independent STAT1 ChIP-seq data
set. The sets contain the top 3000 (left panel) or top 30 000 sites (center & right panel) of the corresponding data. The literature set consists of 37
STAT1 sites collected in the ORegAnno database. The occurrence of GAS is assessed in 100 bp sequence windows (SSA web server http://www.isrec. isb-sib.ch/ssa/). Plotted points represent the center positions of windows relative to the position of the putative STAT1 site predicted from ChIP-seq
data. The right panel displays the frequency of the ISRE PWM (Transfac entry M00258). doi:10.1371/journal.pone.0011425.g001 July 2010 | Volume 5 | Issue 7 | e11425 PLoS ONE | www.plosone.org 2 STAT1 on MER41 cells, or from ChIP input, respectively) does not to provide
significant advantages in terms of precision and content of
consensus STAT1 binding sequences. A sequence motif closely
resembling the GAS consensus is associated with large parts of the
observed ChIP-seq signal. Allowing one mismatch in the GAS
consensus raises its frequency to 95% within 100bp to the
determined binding sites in our set. Consensus sequences with
mismatches are however unspecific descriptors of binding sites as
reflected by background frequencies of 60% in this example. STAT1 sites (see above) and on a subset of 3267 sites depleted of
repetitive sequences. The almost identical motif resulting from
motif discovery on a repeat-filtered set (Fig. 2a & b) indicates a
minimal bias by repetitive sequences. The resistance to bias by
repetitive sequences may however be intrinsic to the method of
motif discovery. An independent reanalysis of the identical ChIP-
seq data set using the popular motif discovery program MEME
[25] on a very similar set of ‘high-coverage’ binding sequences [7]
reports two motifs named M1 and M2. M1 is virtually identical to
the motif found by us. M2 is a highly conserved 20mer sequence
containing a classical GAS motif in the middle. Upon further
analysis (see below) we find that this motif is nearly identical to a
part of a repetitive sequence element containing two GAS sites
(Fig. 2d). Based on these observations, we conclude that M2 is a
motif discovery artifact reflecting repetitive sequences in the
human genome rather than the intrinsic binding preference of
STAT1. Refinement of description of STAT1 binding motif (GAS) Refinement of description of STAT1 binding motif (GAS)
Position-specific scoring approaches using weight matrices
(PWM) or Hidden Markow Models (HMM) feature superior
performances as descriptors of binding preferences [23]. PWMs
enable also the prediction of potential binding sites in genomic
sequences. Previous approaches characterized the binding of
STAT1 in vitro to synthetic oligonucleotides [14]. We observed
that a number of thereby predicted genomic binding sites remain
devoid of the now available STAT1 ChIP-seq data [3]. This
prompted us to investigate potential differences in characteristics
of binding sites in vitro vs. in vivo. A recent high-throughput study of transcription factor binding
specificity challenges our molecular understanding of how proteins
interact with their DNA binding sites by the conclusion that
roughly half of the analyzed proteins recognize multiple distinct
motifs [26]. In order to consider this finding, we re-analyzed our
collections of highly enriched in vivo STAT1 site with an algorithm
reporting multiple motifs (MEME). In this case, the results
obtained with the complete and repeat-filtered sets are strikingly
different. With the complete set, we found three motifs with E-
values in the order of 1021000 or lower (Table 1). The top-ranked
corresponds to the GAS motif. The second and third closely
resemble parts of repetitive element MER41B and alpha satellite
DNA, respectively, reproducing a bias by repetitive sequence as We use the PWM (Fig. 2c) derived from in vitro SELEX assays
[14] as initial model and apply a probabilistic modeling tool [24]
for sequence motif discovery (results in Fig. 2a (sequence logo), and
Fig. 2e (PWM)). Repetitive sequences with a considerable number
of virtually identical sequences tend to impose repeat-specific
characteristics of motifs in probabilistic approaches on repeat-
containing sequence sets. To control for eventual biases brought in
by repeats, we compare the results of independent motif discovery
approaches on the repeat-containing sequence set of the 4446 Figure 2. Descriptors of binding preferences of STAT1. Sequence logos (http://weblogo.berkeley.edu/) visualize the information content of
occurrence frequencies of the 4 nucleotides by variable letter sizes at each position. Sequence logos of MAMOT motifs derived from in vivo ChIP-seq
sites (a), repeat-filtered in vivo ChIP-seq (b), and in vitro SELEX sites (c). Note the symmetrical half sides with the presumable STAT1-interacting
nucleotides are almost identical in a) to c). (d) Alignment of motif M2 (Jothi et al.) with the reverse complement of the consensus sequence of
repetitive element MER41B (repbase). Refinement of description of STAT1 binding motif (GAS) Table (e) specifies the PWM for STAT1 as visualized in panel a), each number indicating a score for matching
nucleotides at corresponding positions. doi:10.1371/journal.pone.0011425.g002
PLoS ONE | www.plosone.org
3
July 2010 | Volume 5 | Issue 7 | e11425 Top 3 motifs (M1 to M3) for both cases are displayed by consensus
sequences and the corresponding E-values indicating an estimate of the
number of motifs with similar or better statistics in a random sequence set. The
striking differences among the secondary motifs indicate a strong bias by
repetitive sequences (M2 and M3 of the complete set resemble sequences from
MER41B, and satellite Satellite/ALR/Alpha, respectively). Their absence in the
repeat-filtered set furthermore suggests a single motif for STAT1 binding in the
non-repetitive part of the human genome. doi:10.1371/journal.pone.0011425.t001 p
q
y
The specificity of the ChIP-seq signal is further underlined by
the coverage at a collection of 37 experimentally characterized
STAT1 binding sites [22] including both GAS and ISRE sites. 7 of
these loci contain only ISRE motifs and lack any GAS matches
(score .30) within 300bp to the ISRE motif. The ISRE motif [15]
is mainly interacting with STAT1–STAT2–IRF9 complexes
formed following stimulation with type-I-interferons, but not with
IFN-c [30]. Accordingly these ISRE loci are occupied by an
average of only 18.1 ChIP-seq tags, whereas the remaining 30 loci
containing GAS exhibit an average of 311.9 tags. The latter
number represents a 60-fold excess of the threshold of 5 tags
applied to determine occupation, evidencing sufficient ChIP-seq
sequencing coverage for our approach. In summary the compar-
ison of sequence-based prediction of STAT1 binding and of
observed ChIP-seq tag counts indicates that the predictions are
hampered by a high number of false positives. This may results in
a reasonable sensitivity, but a very low specificity. observed in the results by Johti et al. With the repeat-filtered set we
also found at the top of the list a motif containing a GAS site with
very low E-value. The second and third-ranked motifs consist of
homopolymers and have considerably higher E-values. Homo-
polymers are strongly over-represented in the human genome and
therefore are, together with repetitive sequences, frequently picked
up by some of the motif finding programs. The still very low E-
values of the homopolymer motifs in the order of 102200 can be
explained by the fact that the background sequence model used by
MEME does not account for their over-representation in natural
DNA. In our interpretation, the lack of any additional motif
ranking higher than commonly found homopolymer motifs
constitutes evidence that IFN-c induced STAT1 recognizes only
a single motif in the non-repetitive part of the human genome. Figure 2. Descriptors of binding preferences of STAT1. Sequence logos (http://weblogo.berkeley.edu/) visualize the information content of
occurrence frequencies of the 4 nucleotides by variable letter sizes at each position. Sequence logos of MAMOT motifs derived from in vivo ChIP-seq
sites (a), repeat-filtered in vivo ChIP-seq (b), and in vitro SELEX sites (c). Note the symmetrical half sides with the presumable STAT1-interacting
nucleotides are almost identical in a) to c). (d) Alignment of motif M2 (Jothi et al.) with the reverse complement of the consensus sequence of
repetitive element MER41B (repbase). Table (e) specifies the PWM for STAT1 as visualized in panel a), each number indicating a score for matching
nucleotides at corresponding positions. doi:10.1371/journal.pone.0011425.g002 Figure 2. Descriptors of binding preferences of STAT1. Sequence logos (http://weblogo.berkeley.edu/) visualize the information content of
occurrence frequencies of the 4 nucleotides by variable letter sizes at each position. Sequence logos of MAMOT motifs derived from in vivo ChIP-seq
sites (a), repeat-filtered in vivo ChIP-seq (b), and in vitro SELEX sites (c). Note the symmetrical half sides with the presumable STAT1-interacting
nucleotides are almost identical in a) to c). (d) Alignment of motif M2 (Jothi et al.) with the reverse complement of the consensus sequence of
repetitive element MER41B (repbase). Table (e) specifies the PWM for STAT1 as visualized in panel a), each number indicating a score for matching
nucleotides at corresponding positions. doi:10.1371/journal.pone.0011425.g002 Figure 2. Descriptors of binding preferences of STAT1. Sequence logos (http://weblogo.berkeley.edu/) visualize the information content of
occurrence frequencies of the 4 nucleotides by variable letter sizes at each position. Sequence logos of MAMOT motifs derived from in vivo ChIP-seq
sites (a), repeat-filtered in vivo ChIP-seq (b), and in vitro SELEX sites (c). Note the symmetrical half sides with the presumable STAT1-interacting
nucleotides are almost identical in a) to c). (d) Alignment of motif M2 (Jothi et al.) with the reverse complement of the consensus sequence of
repetitive element MER41B (repbase). Table (e) specifies the PWM for STAT1 as visualized in panel a), each number indicating a score for matching
nucleotides at corresponding positions. doi:10.1371/journal.pone.0011425.g002 July 2010 | Volume 5 | Issue 7 | e11425 PLoS ONE | www.plosone.org 3 STAT1 on MER41 Table 1. MEME reports motifs derived from repetitive
sequences. In
conclusion the binding preferences of STAT1 in vivo are very
comparable to the in vitro binding of recombinant STAT1 protein
to random oligonucleotides. And the binding sites occupied by
STAT1 in vivo upon IFN-c stimulation do not diverge between
repetitive or non-repetitive genomic loci. Repetitive elements MER41 contain STAT1 binding sites
Approximately one forth of our STAT1 binding sites map
within annotations of repeats (RepeatMasker track in UCSC,
[31]). Remarkably the relative number of STAT1 ChIP-seq reads
within repetitive sequences displays a strong increase following
IFN-c stimulation, ruling out potential systematic mapping
artifacts related to repetitive sequences or to the completely
abnormal karyotype of HeLa cells. The induction of the STAT1
binding is though restricted, the complete class of LTRs and also
other repeat classes do not display significant changes in normal-
ized numbers of ChIP-seq tags upon treatment with IFN-c
(Table 2). Conversely the medium reiteration frequency inter-
spersed repeats MER41B of the class of Long Terminal Repeats
(LTR) feature almost 20-fold more ChIP-seq tags in IFN-c
stimulated cells as compared to unstimulated control (log ratio 2.7
in Table 2). Accordingly 292 (6.5%) of our identified binding sites
are located within MER41 annotations, collecting 41080 (5.4%)
tags, while MER41 elements cover only approximately 4 Mb
(0.1%) of the genome. Motif number
Consensus sequence
E-value in MEME
all STAT1 sites
M1
TTTCCCGGAA
7.7e-3209
M2
TCCACCCCTTGTT-
TAGCATATAATCA
1.6e-1501
M3
TGATGTGTGCATT-
CAACTCAC
9.1e-848
repeat-filtered
M1
GATTTCCGGGAAATG
2.0e-2351
M2
AAAAAAAAAAAAAA-
AAAAAAA
9.6e-205
M3
CCCCTCCCCCGCC-
CCCCCCCC
5.3e-202
Motif discovery using MEME with default parameters on sequences spanning
either the complete set or a repeat-filtered set of STAT1 sites derived from ChIP-
seq data. Top 3 motifs (M1 to M3) for both cases are displayed by consensus
sequences and the corresponding E-values indicating an estimate of the
number of motifs with similar or better statistics in a random sequence set. The
striking differences among the secondary motifs indicate a strong bias by
repetitive sequences (M2 and M3 of the complete set resemble sequences from
MER41B, and satellite Satellite/ALR/Alpha, respectively). Their absence in the
repeat-filtered set furthermore suggests a single motif for STAT1 binding in the
non-repetitive part of the human genome. doi:10.1371/journal.pone.0011425.t001 stimulated by IFN-c, the better a genomic sequence is matching
the PWM, the higher is the probability to be occupied by STAT1. Conversely, the fraction of occupied sites inferred from the ChIP-
seq experiment with unstimulated cells, is largely independent of
the PWM score. This finding indicates that in unstimulated cells,
sequences with putatively higher affinity are not preferentially
bound by STAT1 and sampled by ChIP-seq. Therefore the ChIP-
seq signal in unstimulated HeLa cells consists to a large extent of
unspecific background sequences [3]. Table 1. MEME reports motifs derived from repetitive
sequences. Figure 3 suggests furthermore a PWM score of 30 as threshold
for binding sites exhibiting a marked difference in occupation from
background levels. Therefore such analysis based on in vivo
occupation may complement statistical approaches to define
PWM cutoff scores [27,28]. While
the
observed higher
occupation
in the ChIP-seq
experiment at sites with higher affinity is conceivable with models
of DNA binding [29], the average occupation remains unexpect-
edly low. The fraction of occupied sites with PWM score above 30
remains below 4%, and even high affinity sites with the maximal
PWM score are occupied at a frequency of less than 18%. Motif discovery using MEME with default parameters on sequences spanning
either the complete set or a repeat-filtered set of STAT1 sites derived from ChIP-
seq data. PLoS ONE | www.plosone.org Figure 3. Estimation of PWM cutoff score from fraction of occupied STAT1 binding sites. 5 454 192 potential STAT1 binding sites in the
human genome are grouped according their PWM score. In general the number of occurrences decrease with increasing PWM score, i.e. 664 981 sites
for PWM 20, 213 877 for 30, and 7471 for 42. Missing bars are due to lack of combinations generating the corresponding PWM score. Occupation is
defined as the fraction of sites covered by more than 5 ChIP fragments (within +/2100 bp). Plotted are data derived from ChIP-seq experiments with
unstimulated (open boxes) or IFN-c-stimulated HeLa cells (filled boxes). The dotted line represents the occupation frequency (0.015) at a collection of
4819 random genomic sites in stimulated cells. doi:10.1371/journal.pone.0011425.g003 Table 2. Induction of STAT1 binding within specific repetitive sequences. class
name
Ln ratio
stim
unstim
cov
space
LTR
MER41B
2.69
68619
3978
1069
21
tandem GAS within reps
1.97
65482
7819
1870
21
LTR
MER41E
1.65
3785
618
135
21
LTR
LTR19B
1.64
2460
407
116
+
LTR
MER93B
1.26
2540
616
134
+
LTR
LTR47A
1.19
4709
1222
228
49
LTR
MER41A
0.66
5834
2581
964
+
tandem GAS outside rep
0.63
32731
14948
2900
21
LTR
MER93a
0.60
2194
1026
192
+
LTR
LTR22C
0.59
1204
569
167
+
LTR
MER66C
0.54
1992
989
184
+
tRNA
Class
0.43
3541
1970
108
na
snRNA
Class
0.04
2410
1979
338
na
LTR
Class
0.03
1157617
955767
248357
na
SINE
Class
20.07
1255938
1148004
388907
na
STAT1 ChIP-seq tag counts located within repetitive sequence annotations. The table is sorted according the strongest induction of STAT1 binding (column 3) and
indicates in the top part all major repeat types which cover more than 100 kb of genomic sequence. The lower part shows major repeat classes in the genome
annotation. For comparison the table includes also the STAT1 binding within 400 bp around the center of tandem matches to the STAT1 PWM either within or outside
repetitive sequences (italic). Columns 4 and 5 indicate the number of centered tags within the corresponding repeat in the ChIP-seq data from IFN-c stimulated cells or
from unstimulated cells, respectively. The induction of STAT1 binding by IFN-c is indicated by column 3 representing the natural logarithm of the ratio in (col. 4/col. 5)
normalized by the total tag counts (stim: 15.1M; unstim: 12.9M). Limited occupation of potential STAT1 sites in specific
cell type As shown above, most loci with strong ChIP-seq signals are
associated with an occurrence of the consensus STAT1 binding
site. Therefore we address the question if the genomic nucleotide
sequence and the refined PWM could be used to predict ChIP-seq
tag counts. Our refined PWM allows to establish a comprehensive
catalog of 5 454 192 potential STAT1 binding sites in the human
genome, if using a deliberately low-stringency PWM score
(. = 20, PWM in Fig. 2e). For each PWM score class we compute
the fraction of binding sites occupied by more than 5 ChIP-seq
tags within 100bp distance to the predicted binding site. This
fraction reflects the in vivo occupation by STAT1, which clearly
increases with higher PWM scores (Fig. 3). Thus for cells The specific induction as well as the comparable occupation of
predicted binding sites inside repeats argues against a generalized
‘inactivation’ of repetitive elements as proposed earlier [32]. In
support of the observed binding at MER41 elements, the
consensus sequence of MER41B [33] contains two high scoring
GAS arranged in tandem with a spacing of 21bp (center-to-center
distance). Tandem GAS bound by hetero- or homotetramers of PLoS ONE | www.plosone.org July 2010 | Volume 5 | Issue 7 | e11425 July 2010 | Volume 5 | Issue 7 | e11425 4 STAT1 on MER41 The 6th column indicates the genome coverage in kb and column 7 indicates the spacing in bp between
tandem STAT1 sites within the corresponding consensus sequence. (+) indicates spacing larger than 100bp or a single STAT1 site. Only very specific repetitive elements
display a significant induction, classes with highest coverage and tag counts (e.g. SINEs) display similar tag counts in IFN-c stimulated or unstimulated cells. Tandem
STAT1 sites inside repeat annotations display an almost 4-fold increased induction compared to similar sites outside repeats. doi:10.1371/journal.pone.0011425.t002 Table 2. Induction of STAT1 binding within specific repetitive sequences. STAT1 ChIP-seq tag counts located within repetitive sequence annotations. The table is sorted according the strongest induction of STAT1 binding (column 3) and
indicates in the top part all major repeat types which cover more than 100 kb of genomic sequence. The lower part shows major repeat classes in the genome
annotation. For comparison the table includes also the STAT1 binding within 400 bp around the center of tandem matches to the STAT1 PWM either within or outside
repetitive sequences (italic). Columns 4 and 5 indicate the number of centered tags within the corresponding repeat in the ChIP-seq data from IFN-c stimulated cells or
from unstimulated cells, respectively. The induction of STAT1 binding by IFN-c is indicated by column 3 representing the natural logarithm of the ratio in (col. 4/col. 5)
normalized by the total tag counts (stim: 15.1M; unstim: 12.9M). The 6th column indicates the genome coverage in kb and column 7 indicates the spacing in bp between
tandem STAT1 sites within the corresponding consensus sequence. (+) indicates spacing larger than 100bp or a single STAT1 site. Only very specific repetitive elements
display a significant induction, classes with highest coverage and tag counts (e.g. SINEs) display similar tag counts in IFN-c stimulated or unstimulated cells. Tandem
STAT1 sites inside repeat annotations display an almost 4-fold increased induction compared to similar sites outside repeats. doi:10.1371/journal.pone.0011425.t002 STAT1 ChIP-seq tag counts located within repetitive sequence annotations. The table is sorted according the strongest induction of STAT1 binding (column 3) and
indicates in the top part all major repeat types which cover more than 100 kb of genomic sequence. The lower part shows major repeat classes in the genome
annotation. For comparison the table includes also the STAT1 binding within 400 bp around the center of tandem matches to the STAT1 PWM either within or outside
repetitive sequences (italic). Induced GAS tandems display a preference of spacing
18–21 bp In summary, occupied individual STAT1 binding sites within
repetitive sequences do in general not differ significantly from
similar sites in non-repetitive parts of the genome, as indicated by
comparable populations of STAT1 binding sites observed in the
refinement of PWMs. In contrast the distribution of spacings
separating GAS tandems displays clear differences between
repetitive and non-repetitive sequences. A combined genome-
wide analysis would therefore lead to a biased value of 21 bp for
an optimal spacing and incorrect conclusions on structural
arrangements of STAT1 complexes on the DNA helix. Eukaryotic transcription factors commonly act as multimeric
complexes recognizing two or more DNA motif that occur at
appropriate distances from each other. Tandem GAS sites may be
part of such complex regulatory modules. Literature reports of
tandem GAS sites in promoters of genes induced by STATs (for
review [37]) support our observation of a coexistence of tandem
STAT1 binding sites both within repeats as well as outside
repetitive sequence annotations. In order to reveal features of
tandem GAS sites potentially predicting their affinity to STAT1,
we analyzed the occupation by ChIP-seq fragments at putatively
‘high-affinity’ tandem sites (average PWM score .30) depending
on the center-to-center spacing between GAS tandem sites. The
induction of STAT1 binding by IFN-c stimulation and the spacing
of GAS tandems exhibit considerable heterogeneity as displayed in
Fig. 4, equally for sites within repetitive as well as within non-
repetitive sequences. Concordantly with the limited occupation
described above, a significant portion of sites exhibit no change in
binding (log ratio = 0), mostly associated with 0 counts in both
stimulated and unstimulated data sets. If selecting sites with
induced binding (log ratio .2), repetitive sequences feature a high Columns 4 and 5 indicate the number of centered tags within the corresponding repeat in the ChIP-seq data from IFN-c stimulated cells or
from unstimulated cells, respectively. The induction of STAT1 binding by IFN-c is indicated by column 3 representing the natural logarithm of the ratio in (col. 4/col. 5)
normalized by the total tag counts (stim: 15.1M; unstim: 12.9M). The 6th column indicates the genome coverage in kb and column 7 indicates the spacing in bp between
tandem STAT1 sites within the corresponding consensus sequence. (+) indicates spacing larger than 100bp or a single STAT1 site. Only very specific repetitive elements
display a significant induction, classes with highest coverage and tag counts (e.g. SINEs) display similar tag counts in IFN-c stimulated or unstimulated cells. Tandem
STAT1 sites inside repeat annotations display an almost 4-fold increased induction compared to similar sites outside repeats. doi:10.1371/journal.pone.0011425.t002 July 2010 | Volume 5 | Issue 7 | e11425 PLoS ONE | www.plosone.org 5 STAT1 on MER41 STAT family members have been reported previously with
ambiguous spacings [34,35,36]. proportion of exact spacing of 21 bp, whereas sites within non-
repetitive sequences display slightly less pronounced preferences
for spacings of 18–21 bp (Fig. 4). Within repeats, 21 bp spacing is
mostly associated with MER41 annotation. Unoccupied STAT1 sites display phylogenetic
conservation Functional TFBS are plausibly under selective pressure and
should thus display an enhanced conservation in closely related
species. To assess the conservation of human STAT1 sites within
non-repetitive sequences, PhastCons scores [38] were averaged
over predicted high-affinity STAT1 sites with PWM scores .30. Repeat sequences spoil multiple genome alignments used for the
computation of PhastCons scores, therefore we limit this analysis
to 298 431 sites within non-repetitive sequences. We split the Figure 4. Spacings of GAS tandems differ in repetitive sequences. Putatively ‘high-affinity’ tandem GAS (average PWM score .30) are
classified according the spacing between the centers of two sites (x axis), and the induction ratios (y axis). For each spacing class, histograms
representing the frequencies of corresponding log ratios are displayed in vertical orientation. Red color indicates location within repetitive sequence
annotations and blue specifies tandem GAS within non-repetitive sequences. Two histograms at the bottom summarize the data above for sites with
induced binding (log ratio .2). Within non-repetitive sequences spacings 18–22 bp are moderately enriched in induced GAS tandems. For induced
sites within repetitive sequences, a clear predominance of spacing 21 bp is observed, mostly related with MER41 repeats. doi:10.1371/journal.pone.0011425.g004 Figure 4. Spacings of GAS tandems differ in repetitive sequences. Putatively ‘high-affinity’ tandem GAS (average PWM score .30) are
classified according the spacing between the centers of two sites (x axis), and the induction ratios (y axis). For each spacing class, histograms
representing the frequencies of corresponding log ratios are displayed in vertical orientation. Red color indicates location within repetitive sequence
annotations and blue specifies tandem GAS within non-repetitive sequences. Two histograms at the bottom summarize the data above for sites with
induced binding (log ratio .2). Within non-repetitive sequences spacings 18–22 bp are moderately enriched in induced GAS tandems. For induced
sites within repetitive sequences, a clear predominance of spacing 21 bp is observed, mostly related with MER41 repeats. doi:10.1371/journal.pone.0011425.g004 PLoS ONE | www.plosone.org July 2010 | Volume 5 | Issue 7 | e11425 6 STAT1 on MER41 evidence for binding sites diverging significantly from the GAS
motif [3,12]. predicted STAT1 sites into 4 classes according to their occupation
with ChIP-seq tags and further separate sites located at TSS
(within 1 kb to annotated TSS) from those distant to TSS. Table 3
displays the statistics of number of sites and average PWM scores
for each class. Putative binding sites with very restricted occupation The limited correlation of the predicted affinity (PWM score) and
the observed STAT1 ChIP-seq signal as presented here suggests
that genomic features additional to the nucleotide sequence
determine the genomic binding of STAT1. Such mechanisms are
likely generalized to all transcription factors and obvious candidates
include cooperative effects between multiple DNA binding proteins. Epigenetic modifications may reduce the accessibility of the DNA
by chromatin compaction [41] and nucleosome positioning might
conceivably interfere with DNA binding [42]. In agreement with a
number of recent studies [43], the prediction of DNA-protein
interactions solely on the basis of the nucleotide sequence or on their
phylogenetic conservation yields in an inaccurate set of sites actually
occupied in a specific cellular condition. Unoccupied ‘perfect’
STAT1 binding sites may include cell type specific binding sites and
suggest a required but not sufficient function of the nucleotide
sequence for DNA-protein binding. The resulting Fig. 5 shows a clear increase of the average of
PhastCons scores precisely at the predicted positions for all sets of
STAT1 sites. In general there is a tendency of increased
conservation at STAT1 sites with higher ChIP-seq occupation,
and sites close to TSS display a still increased and positionally
broader conservation profile. The set of sites with highest
occupation is associated with highest average conservation scores,
remarkably independent on their location close or distant to
annotated TSS. Striking is also the conservation profile of STAT1
sites close to TSS, but not occupied by any ChIP-seq tags in HeLa
cells. The high average PhastCons scores of genomic sequences in
close vicinity to the predicted STAT1 sites may originate from
their location within regulatory modules. The clearly enhanced
conservation of the precise location of STAT1 sites not occupied
in HeLa cells might hint for a function most likely as binding site
either in other cell types or by related members of the family of
STAT transcription factors. Unoccupied STAT1 sites display phylogenetic
conservation The average PWM scores only slightly increase with
increased ChIP-seq occupation, likely due to limited occupation of
predicted high-affinity STAT1 sites (Fig. 3). STAT1 binding on repeats The present study extends the analysis of STAT1 binding for the
first time to repetitive elements. In distinction to previous reports on
binding
sites
of
other
transcription
factors
within
repeats
[18,19,20,21], we demonstrate a specific induction of STAT1
binding to selected repetitive sequence elements in reaction to a
signal increasing the nuclear concentration of STAT1. The sharp peaks with a width of a few 10 bp putatively identify
conserved STAT1 sites, either isolated or within conserved
regulatory modules. However does this analysis also detect STAT1
sites with augmented conservation which lack any ChIP-seq tags in
stimulated HeLa cells. This suggests a limited predictability of TF-
binding in a specific cell type, even if nucleotide sequences with
preferred binding (via PWM) and phylogenetic conservation are
combined. ChIP-seq signals are at present not reliably predictable by features
of genomic sequences. Extended analysis of ChIP-seq data in HeLa
cells including additional DNA binding proteins [12] and further
sequence analysis approaches might however reveal combinations of
features to better explain the observed binding of STAT1. Aspects of ChIP-seq data analysis Aspects of ChIP-seq data analysis The binding of STAT1 within repetitive sequences of the LTR
class might relate to the description of functional GAS sites in
retroviruses [44]. Of particular interest may be the fact that the
detected MER41 repeats expanded only in the primate lineage. In
contrast, the STAT1 pathway and thus STAT1 binding sites are
found in species as distant as insects. Therefore the IFN-c – STAT
pathway precedes the expansion of MER41 repeats by several
hundreds of millions years of evolution. Consequently the
expansion of MER41 elements in the primate lineage likely
remodeled parts of the pre-existing regulatory mechanisms of gene
expression. This hypothesis is consistent with a previous study [18]
concluding on an analogous role of a distantly related transcription
factor (p53) binding to distinct LTR subfamilies. In particular
MER41 may contribute to the divergence between primates and This study aims at the identification of a reference set of robustly
induced STAT1 binding sites upon IFN-c stimulation. Many of
the recent approaches in the analysis of ChIP-seq data use
methods with similar underlying principles to determine genomic
loci
with
elevated
ChIP-seq
signal
(peak
detection). Main
differences consist in the determination of the threshold of signal
intensities which separate signal from background noise. The noise
level in ChIP-seq is still poorly characterized. Therefore the
STAT1 binding motif obtained in the present study does not take
into account putative low affinity sites. For the detection of low
affinity binding sites, specialized approaches may be used [39,40]. Approaches including also ‘weaker’ putative binding sites with
very low ChIP-seq coverage did however so far not provide Table 3. Predicted STAT1 binding sites classified according coverage by ChIP-seq tags in HeLa cells stimulated by IFN-c. Occupation class
1
2
3
4
# of ChIP-seq tags
0
1-5
6-14
.14
PWM score average (+/2 standard
deviation)
34.15+/22.57
34.34+/22.67
35.21+/23.08
35.89+/23.07
# of sites distant to TSS
109532
165577
9029
5050
# of sites at TSS
2821
4508
1001
913
298 431 high-affinity STAT1 sites (PWM scores .30) are split into 4 classes according to their occupation with ChIP-seq tags. The sets are further separated into sites
located within 1kb to an annotated TSS and those distant to TSS. doi:10.1371/journal.pone.0011425.t003 T1 binding sites classified according coverage by ChIP-seq tags in HeLa cells stimulated by IFN-c. Table 3. Aspects of ChIP-seq data analysis Unfortu-
nately we could not find genome wide gene expression data of
IFN-c stimulated HeLa cells in public data repositories. At the
example of the locus of SECTM1 on human chr17, we identified a
gene regulated by IFN-c in human monocytes [46] featuring an
upstream MER41 element at 5 kb to the TSS with two high
scoring GAS in tandem. A duplication event in the rodent lineage
created two gene copies (Sectm1a and Sectm1b), which display
g
p y g
doi:10.1371/journal.pone.0011425.g005
Table 4. MER41 is under-represented in coding exons, but
not in upstream regions. Number of
MER41
instances
Length of
genome
compartment
in Mb
Ratio over
genome
average
Genome
7 197
3 093
1
coding exons
8
35
0.09
10 kb upstream
region
1 183
347
1.46
Annotations of MER41 repetitive sequence elements in the human genome
(approx. average length: 330 bp) are selected depending on their location in
coding exons or in 10 kb upstream regions of TSS annotations (at least 10 bp
overlap). The cumulative length of the corresponding genomic sequences is
used to determine a ratio relative to random expectation. doi:10.1371/journal.pone.0011425.t004
PLoS ONE | www.plosone.org clearly tissue expression patterns divergent from human SECTM1
[47]. Incidentally we do not find MER41 annotations in the
upstream regions of a set of 10 genes with a common IFN-c
induction in both human and mouse tissues and associated with
STAT1 binding sites [48]. Future comparative gene expression
assays in corresponding cell types might focus on differential gene
expression associated with the presence or absence of MER41
repeats in human and mouse, respectively. rodents. Thus the contribution of repetitive sequence elements
could be included in detailed studies of the evolution of regulatory
networks, exemplified by a recent analysis on the transcriptional
repressor REST [45]. The DNA binding of TFs does however not
allow
definitive
conclusions
of
transcriptional
regulation
of
neighboring genes. Anticipating considerable experimental diffi-
culties to target repetitive sequences by mutagenesis approaches,
we discuss circumstantial evidence for potential functions of
MER41 repeats in IFN-c induced gene regulation. At first the
presence of MER41 annotations in the 10 kb upstream regions
appears not under negative selection pressure (Table 4). Unfortu-
nately we could not find genome wide gene expression data of
IFN-c stimulated HeLa cells in public data repositories. ChIP-Seq data The ChIP-seq data underlying this study are described in [3]. Results from ChIP-Seq experiments carried out with unstimulated
and stimulated HeLa cells were downloaded from http://www. bcgsc.ca/downloads/chiptf/, providing 2 files with the genomic
coordinates of 12.9 million, and 15.1 million mapped sequence
tags of unstimulated and stimulated HeLa cells, respectively. Annotations of MER41 repetitive sequence elements in the human genome
(approx. average length: 330 bp) are selected depending on their location in
coding exons or in 10 kb upstream regions of TSS annotations (at least 10 bp
overlap). The cumulative length of the corresponding genomic sequences is
used to determine a ratio relative to random expectation. doi:10.1371/journal.pone.0011425.t004 Annotations of MER41 repetitive sequence elements in the human genome
(approx. average length: 330 bp) are selected depending on their location in
coding exons or in 10 kb upstream regions of TSS annotations (at least 10 bp
overlap). The cumulative length of the corresponding genomic sequences is
used to determine a ratio relative to random expectation. doi:10.1371/journal.pone.0011425.t004 Aspects of ChIP-seq data analysis At the
example of the locus of SECTM1 on human chr17, we identified a
gene regulated by IFN-c in human monocytes [46] featuring an
upstream MER41 element at 5 kb to the TSS with two high
scoring GAS in tandem. A duplication event in the rodent lineage
created two gene copies (Sectm1a and Sectm1b), which display Our analysis confirms the previously described enhanced
resolution of the ChIP-seq approach. However, ‘negative control’
data exploited by some of the current peak calling algorithms don’t
provide substantial advantages. We extend initial characterizations
of STAT1 ChIP-seq data sets to binding sites within repetitive
sequence elements. The selective induction of ChIP-seq signal at
specific repeats upon cellular stimulation corroborates specific
binding by STAT1. These observations bolster previous reports on
binding sites of other TFs within repeats. Repetitive elements may
however bring in biases deflecting the analysis of binding
sequences. We recommend therefore an independent analysis of
sequences derived from ChIP-seq data within repetitive and within
non-repetitive genomic sequences, in order to avoid incorrect
conclusions on general properties of binding sites. Table 4. MER41 is under-represented in coding exons, but
not in upstream regions. Table 4. MER41 is under-represented in coding exons, but
not in upstream regions. Number of
MER41
instances
Length of
genome
compartment
in Mb
Ratio over
genome
average
Genome
7 197
3 093
1
coding exons
8
35
0.09
10 kb upstream
region
1 183
347
1.46
Annotations of MER41 repetitive sequence elements in the human genome
(approx. average length: 330 bp) are selected depending on their location in
coding exons or in 10 kb upstream regions of TSS annotations (at least 10 bp
overlap). The cumulative length of the corresponding genomic sequences is
used to determine a ratio relative to random expectation. doi:10.1371/journal.pone.0011425.t004 Aspects of ChIP-seq data analysis For each of the sets (Ta
STAT1 sites. In general STAT1 sites display a narrow increa
TSS: 0.28). Closely neighboring TSS increase the average
STAT1 sites. On the other hand TSS-associated STAT1 site
observation may suggest limited predictability of TF-bin
binding (PWM) and on phylogenetic conservation are co
doi:10.1371/journal.pone.0011425.g005
Table 4. MER41 is under-represented in coding
not in upstream regions. Number of
MER41
instances
Length of
genome
compartment
in Mb
Ra
ge
av
Genome
7 197
3 093
1
coding exons
8
35
0.0
10 kb upstream
region
1 183
347
1.4
Annotations of MER41 repetitive sequence elements in the hu
(approx. average length: 330 bp) are selected depending on th
coding exons or in 10 kb upstream regions of TSS annotations
overlap). The cumulative length of the corresponding genomic
used to determine a ratio relative to random expectation. doi:10.1371/journal.pone.0011425.t004
PLoS ONE | www.plosone.org Figure 5. STAT1 sites unoccupied in HeLa cells nevertheless with increased phylogenetic conservation. STAT1 sites within non-
repetitive sequences are classified according to the occupation by ChIP-seq tags and to their location either distant (.1 kb; solid lines) or close to
annotations of TSS (dotted lines). For each of the sets (Table 3), the average PhastCons scores are computed at positions relative to the predicted
STAT1 sites. In general STAT1 sites display a narrow increase of the average conservation score. (averages of PhastCons scores: genome wide 0.07; at
TSS: 0.28). Closely neighboring TSS increase the average conservation, as well as higher ChIP-seq occupation tends to increased conservation at
STAT1 sites. On the other hand TSS-associated STAT1 sites which lack any ChIP-seq tags still display a clearly augmented average conservation. This
observation may suggest limited predictability of TF-binding in a specific cell type, even if information on nucleotide sequences with preferred
binding (PWM) and on phylogenetic conservation are combined. doi:10.1371/journal.pone.0011425.g005 rodents. Thus the contribution of repetitive sequence elements
could be included in detailed studies of the evolution of regulatory
networks, exemplified by a recent analysis on the transcriptional
repressor REST [45]. The DNA binding of TFs does however not
allow
definitive
conclusions
of
transcriptional
regulation
of
neighboring genes. Anticipating considerable experimental diffi-
culties to target repetitive sequences by mutagenesis approaches,
we discuss circumstantial evidence for potential functions of
MER41 repeats in IFN-c induced gene regulation. At first the
presence of MER41 annotations in the 10 kb upstream regions
appears not under negative selection pressure (Table 4). Aspects of ChIP-seq data analysis Predicted STAT1 binding sites classified according coverage by ChIP-seq tags in HeLa cells st 298 431 high-affinity STAT1 sites (PWM scores .30) are split into 4 classes according to their occupation with ChIP-seq tags. The sets are further separated into sites
located within 1kb to an annotated TSS and those distant to TSS. doi:10.1371/journal.pone.0011425.t003 July 2010 | Volume 5 | Issue 7 | e11425 PLoS ONE | www.plosone.org 7 STAT1 on MER41 Figure 5. STAT1 sites unoccupied in HeLa cells nevertheless with increased phylogenetic conservation. STAT1 sites within non-
repetitive sequences are classified according to the occupation by ChIP-seq tags and to their location either distant (.1 kb; solid lines) or close to
annotations of TSS (dotted lines). For each of the sets (Table 3), the average PhastCons scores are computed at positions relative to the predicted
STAT1 sites. In general STAT1 sites display a narrow increase of the average conservation score. (averages of PhastCons scores: genome wide 0.07; at
TSS: 0.28). Closely neighboring TSS increase the average conservation, as well as higher ChIP-seq occupation tends to increased conservation at
STAT1 sites. On the other hand TSS-associated STAT1 sites which lack any ChIP-seq tags still display a clearly augmented average conservation. This
observation may suggest limited predictability of TF-binding in a specific cell type, even if information on nucleotide sequences with preferred
binding (PWM) and on phylogenetic conservation are combined. doi:10.1371/journal.pone.0011425.g005 rodents. Thus the contribution of repetitive sequen
could be included in detailed studies of the evolution
networks, exemplified by a recent analysis on the tr
repressor REST [45]. The DNA binding of TFs does
allow
definitive
conclusions
of
transcriptional
re
neighboring genes. Anticipating considerable experi
culties to target repetitive sequences by mutagenesis
we discuss circumstantial evidence for potential
MER41 repeats in IFN-c induced gene regulation. presence of MER41 annotations in the 10 kb upstr
appears not under negative selection pressure (Table
nately we could not find genome wide gene expres
IFN-c stimulated HeLa cells in public data reposito
example of the locus of SECTM1 on human chr17, w
gene regulated by IFN-c in human monocytes [46]
upstream MER41 element at 5 kb to the TSS wi
scoring GAS in tandem. A duplication event in the ro
created two gene copies (Sectm1a and Sectm1b), w
Figure 5. STAT1 sites unoccupied in HeLa cells n
repetitive sequences are classified according to the occup
annotations of TSS (dotted lines). Tag centering and peak detection The source files were converted in SGA (Simple Genome
Annotation) format, the working format of our ChIP-Seq tools
available at http://ccg.vital-it.ch/chipseq/, http://sourceforge.net/ July 2010 | Volume 5 | Issue 7 | e11425 PLoS ONE | www.plosone.org 8 STAT1 on MER41 specificity by a standard position weight matrix (PWM) with
spacer length 3. The probability matrix extracted from the trained
HMM (shown as sequence Logo in Fig. 1a) was converted into an
integer PWM (shown in Figure 2a) using the following formula: projects/chip-seq/. An SGA file is a tab-delimited text file with five
obligatory fields per line: chromosome, feature name, position,
strand, and a number representing the count of sequenced tags
mapping to this position. The position field corresponds to the
chromosomal position of the 59 end of the mapped sequence tag, that
is the beginning of the matching region for tags on the positive (+)
strand, or the end position of tags on the negative (2) strand. SGA
files are sorted by chromosome, position and strand, allowing for
rapid, sequential processing by downstream analysis tools. wib~int
3
ln 2
ð Þ |ln
pib
0:25
pib is the probability of base b at binding site position i, and wib is
the corresponding weight in the scoring matrix. The function int
rounds the argument to the nearest integer. The choice of the
scaling factor 3/log(2) is arbitrary. Note that 3 score units
correspond to a factor of 2 in terms of base frequencies. Putative
binding sites can be scored by aligning their nucleotide sequence
to the PWM and sum the matching scores over all positions. The average length of the pulled-down fragments was estimated
with the aid of the ChIP-cor program of the ChIP-seq tools. The
ChIP-cor program generates a histogram indicating how many
times a 2 strand tag is found at a particular distance of a + strand
tag. In ChIP-seq experiments, + and 2 strand tags tend to occur in
equivalent numbers in clusters around the transcription factor
binding site. The relative displacement of + and 2 tags visualized
by ChIP-cor serves as estimation of the typical fragment size,
found to be 140 bp in these ChIP-seq experiments. An additional
ChIP-center program generates ‘‘centered’’ SGA files by adding or
subtracting a user-defined distance from the positions of the + and
2 tags, respectively, in the input SGA files. Acknowledgments mamot{Bae{i 20 {t {w 1:0 {m stat1 init:model peak:seq mamot{Bae{i 20 {t {w 1:0 {m stat1 init:model peak:seq The authors would like to thank Felix Naef and Vidhya Gnanasekaran for
critical reading of the manuscript. The initial model considers alternative spacer lengths of 2, 3 and
4 bases between the consensus half-site motifs TTC and GAA in
the initial model. The resulting trained HMM assigned very low
probabilities (below 1%) to the spacing classes 2 and 4, which
allows to ignore these classes and to represent the STAT1 binding Average conservation scores at STAT1 binding sites g
g
PhastCons scores on human genome coordinates derived from
the 17-way vertebrate genomes alignment were obtained from the
UCSC genome browser [31]. Converting PhastCons scores for each
position into a density representation allows for efficient computa-
tion of average PhastCons scores using ChIP-cor (http://ccg.vital-it. ch/chipseq/) and applying count density normalization. GAS motif refinement The refinement of the STAT1 binding motif description was
carried out using the MArkow MOdeling Tool (MAMOT [24])
starting from the same initial Hidden Markov Model (HMM) as in
a previous work [14]. As a training set, we used 200 bp long
sequence fragments centered at 4446 peak positions obtained as
described above. The STAT1 binding site model was refined with
MAMOT implementing classical Baum-Welch training with the
following parameter settings: Found
at:
doi:10.1371/journal.pone.0011425.s001
(0.14
MB
TXT) File S2
List of 4446 STAT1 binding sites in bed format
(uploaded to UCSC Genome Browser). Found
at:
doi:10.1371/journal.pone.0011425.s002
(0.15
MB
TXT) Supporting Information File S1
List of 4446 STAT1 binding sites in sga format
(uploaded to ChIP-seq web server). File S1
List of 4446 STAT1 binding sites in sga format
(uploaded to ChIP-seq web server). Tag centering and peak detection The strand field is
changed to 0 to reflect the unoriented nature of the center
positions defined in the output SGA file. Based on the estimated
fragment length, we used a centering distance of 70 bp for SGA
files of both stimulated and unstimulated ChIP-seq experiments. Determining the occupation of predicted sites A genome-wide map of predicted STAT1 binding sites was
generated as follows. A list of 11-mer sequences matching the
weight matrix shown in Fig. 2a with a score $20 was compiled
with a perl script. The fetchGWI program [49] was used to
determine all exact matches of all corresponding 11-mer sequences
on the genome. We then determined STAT1 occupancy by
counting the number of centered tags from the stimulated and
unstimulated data set within a window of 6100bp relative to the
center position of predicted sites. The centered SGA files were used as input to the peak detection
program ChIP-peak. The following summarizes the concepts of the
ChIP-peak program. Each line of the sorted input SGA file is
considered as candidate peak, for which the total number of
mapped tags in a window of chromosomal positions is computed
using neighboring lines in the SGA file. This window is centered on
the position, with a user-specified width. In order to be retained as a
peak, a candidate position must have at least a threshold number of
total tags. Moreover, it must be the position with the highest
number of counts within a so-called vicinity range, an additional
user-specified parameter of the width of a position-centered
window. If an input SGA line is retained as a peak, its position
may be optionally redefined as the center of gravity of the tag counts
in the surrounding window. The weight of sporadically occurring
positions with suspiciously high tag counts can be decreased by a
user-specified count cut-off value. Counts in the input file exceeding
this value are replaced by the cut-off value. In this work, we used a
window width of 200 bp, and a vicinity range of 400 bp, a
(stringent) threshold of 50 counts, and a permissive count cut-off
value of 999999. A posteriori peak refinement was turned off. Measure of induction of STAT1 binding by IFN-c The counts of the stimulated and the unstimulated ChIP-seq tag
counts at a specific locus were augmented by one pseudocount,
normalized by the total number of tags in the corresponding
ChIP-seq experiment (stim: 15250744; unstim: 13019977 tags),
and the natural logarithm was calculated of the ratio ‘stimulated’
over ‘unstimulated’ (log ratio). References Ward LD, Bussemaker HJ (2008) Predicting functional transcription factor
binding through alignment-free and affinity-based analysis of orthologous
promoter sequences. Bioinformatics 24: i165–171. 16. Polak P, Domany E (2006) Alu elements contain many binding sites for
transcription factors and may play a role in regulation of developmental
processes. BMC Genomics 7: 133. 41. Robertson AG, Bilenky M, Tam A, Zhao Y, Zeng T, et al. (2008) Genome wide
relationship between histone H3 lysine 4 mono- and tri-methylation and
transcription factor binding. Genome Res 18: 1906–1917. 17. Mortazavi A, Leeper Thompson EC, Garcia ST, Myers RM, Wold B (2006)
Comparative genomics modeling of the NRSF/REST repressor network: from
single conserved sites to genome-wide repertoire. Genome Res 16: 1208–1221. 42. Kaplan N, Moore IK, Fondufe-Mittendorf Y, Gossett AJ, Tillo D, et al. (2009)
The DNA-encoded nucleosome organization of a eukaryotic genome. Nature
458: 362–366. 18. Wang T, Zeng J, Lowe CB, Sellers RG, Salama SR, et al. (2007) Species-specific
endogenous retroviruses shape the transcriptional network of the human tumor
suppressor protein p53. Proc Natl Acad Sci U S A 104: 18613–18618. 43. Whitington T, Perkins AC, Bailey TL (2009) High-throughput chromatin
information enables accurate tissue-specific prediction of transcription factor
binding sites. Nucleic Acids Res 37: 14–25. pp
p
p
19. Laperriere D, Wang TT, White JH, Mader S (2007) Widespread Alu repeat-
driven expansion of consensus DR2 retinoic acid response elements during
primate evolution. BMC Genomics 8: 23. 44. Sepp T, Tong-Starksen SE (1997) STAT1 pathway is involved in activation of
caprine arthritis-encephalitis virus long terminal repeat in monocytes. J Virol 71:
771–777. 20. Johnson R, Gamblin RJ, Ooi L, Bruce AW, Donaldson IJ, et al. (2006)
Identification of the REST regulon reveals extensive transposable element-
mediated binding site duplication. Nucleic Acids Res 34: 3862–3877. 45. Johnson R, Samuel J, Ng CKL, Jauch R, Stanton LW, et al. (2009) Evolution of
the vertebrate gene regulatory network controlled by the transcriptional
repressor REST. Mol. Biol. Evol 26: 1491–1507. 21. Bourque G, Leong B, Vega VB, Chen X, Lee YL, et al. (2008) Evolution of the
mammalian transcription factor binding repertoire via transposable elements. Genome Res 18: 1752–1762. 46. Ackermann-Liebrich U, Kuna-Dibbert B, Probst-Hensch NM, Schindler C,
Felber Dietrich D, et al. (2005) Follow-up of the Swiss Cohort Study on Air
Pollution and Lung Diseases in Adults (SAPALDIA 2) 1991-2003: methods and
characterization of participants. Soz Praventivmed 50: 245–263. 22. References Jurka J (2000) Repbase update: a database and an electronic journal of repetitive
elements. Trends Genet 16: 418–420. 9. Valouev A, Johnson DS, Sundquist A, Medina C, Anton E, et al. (2008)
Genome-wide analysis of transcription factor binding sites based on ChIP-Seq
data. Nat Methods 5: 829–834. 34. Li X, Leung S, Burns C, Stark GR (1998) Cooperative binding of Stat1-2
heterodimers and ISGF3 to tandem DNA elements. Biochimie 80: 703–710. 35. Lecine P, Algarte M, Rameil P, Beadling C, Bucher P, et al. (1996) Elf-1 and
Stat5 bind to a critical element in a new enhancer of the human interleukin-2
receptor alpha gene. Mol Cell Biol 16: 6829–6840. 10. Xu H, Wei CL, Lin F, Sung WK (2008) An HMM approach to genome-wide
identification of differential histone modification sites from ChIP-seq data. Bioinformatics 24: 2344–2349. 36. Vinkemeier U, Cohen SL, Moarefi I, Chait BT, Kuriyan J, et al. (1996) DNA
binding of in vitro activated Stat1 alpha, Stat1 beta and truncated Stat1:
interaction between NH2-terminal domains stabilizes binding of two dimers to
tandem DNA sites. Embo J 15: 5616–5626. 11. Zhang ZD, Rozowsky J, Snyder M, Chang J, Gerstein M (2008) Modeling ChIP
sequencing in silico with applications. PLoS Comput Biol 4: e1000158. 12. Rozowsky J, Euskirchen G, Auerbach RK, Zhang ZD, Gibson T, et al. (2009)
PeakSeq enables systematic scoring of ChIP-seq experiments relative to controls. Nat Biotechnol 27: 66–75. 37. Stark GR, Kerr IM, Williams BR, Silverman RH, Schreiber RD (1998) How
cells respond to interferons. Annu Rev Biochem 67: 227–264. 13. Darnell JE, Jr., Kerr IM, Stark GR (1994) Jak-STAT pathways and
transcriptional activation in response to IFNs and other extracellular signaling
proteins. Science 264: 1415–1421. 38. Siepel A, Bejerano G, Pedersen JS, Hinrichs AS, Hou M, et al. (2005)
Evolutionarily conserved elements in vertebrate, insect, worm, and yeast
genomes. Genome Res 15: 1034–1050. p
14. Ehret GB, Reichenbach P, Schindler U, Horvath CM, Fritz S, et al. (2001) DNA
binding specificity of different STAT proteins. Comparison of in vitro specificity
with natural target sites. J Biol Chem 276: 6675–6688. g
39. Tanay A (2006) Extensive low-affinity transcriptional interactions in the yeast
genome. Genome Res 16: 962–972. 15. Levy DE, Kessler DS, Pine R, Reich N, Darnell JE, Jr. (1988) Interferon-
induced nuclear factors that bind a shared promoter element correlate with
positive and negative transcriptional control. Genes Dev 2: 383–393. 40. References Conference on Intelligent Systems for Molecular Biology, AAAI Press, Menlo
Park, California. pp 28–36. 1. Tompa M, Li N, Bailey TL, Church GM, De Moor B, et al. (2005) Assessing
computational tools for the discovery of transcription factor binding sites. Nat
Biotechnol 23: 137–144. 26. Badis G, Berger MF, Philippakis AA, Talukder S, Gehrke AR, et al. (2009)
Diversity and complexity in DNA recognition by transcription factors. Science
324: 1720–1723. 2. Hu J, Li B, Kihara D (2005) Limitations and potentials of current motif
discovery algorithms. Nucleic Acids Res 33: 4899–4913. 3. Robertson G, Hirst M, Bainbridge M, Bilenky M, Zhao Y, et al. (2007) Genome-
wide profiles of STAT1 DNA association using chromatin immunoprecipitation
and massively parallel sequencing. Nat Methods 4: 651–657. 27. Bailey TL, Gribskov M (1998) Combining evidence using p-values: application
to sequence homology searches. Bioinformatics 14: 48–54. 28. van Nimwegen E (2007) Finding regulatory elements and regulatory motifs: a
general probabilistic framework. BMC Bioinformatics 8 Suppl 6: S4. y p
q
g
4. Schmid CD, Bucher P (2007) ChIP-Seq Data Reveal Nucleosome Architecture
of Human Promoters. Cell 131: 831–832. general probabilistic framework. BMC Bioinformatics 8 Suppl 6: S4. 29. Berg OG, von Hippel PH (1987) Selection of DNA binding sites by regulatory
proteins. Statistical-mechanical theory and application to operators and
promoters. J Mol Biol 193: 723–750. 5. Fejes AP, Robertson G, Bilenky M, Varhol R, Bainbridge M, et al. (2008)
FindPeaks 3.1: a tool for identifying areas of enrichment from massively parallel
short-read sequencing technology. Bioinformatics 24: 1729–1730. 30. Platanias LC (2005) Mechanisms of type-I- and type-II-interferon-mediated
signalling. Nat Rev Immunol 5: 375–386. 6. Ji H, Jiang H, Ma W, Johnson DS, Myers RM, et al. (2008) An integrated
software system for analyzing ChIP-chip and ChIP-seq data. Nat Biotechnol 26:
1293–1300. 31. Karolchik D, Kuhn RM, Baertsch R, Barber GP, Clawson H, et al. (2008) The
UCSC Genome Browser Database: 2008 update. Nucleic Acids Res 36:
D773–779. 7. Jothi R, Cuddapah S, Barski A, Cui K, Zhao K (2008) Genome-wide
identification of in vivo protein-DNA binding sites from ChIP-Seq data. Nucleic
Acids Res 36: 5221–5231. 32. Yoder JA, Walsh CP, Bestor TH (1997) Cytosine methylation and the ecology of
intragenomic parasites. Trends Genet 13: 335–340. 8. Kharchenko PV, Tolstorukov MY, Park PJ (2008) Design and analysis of ChIP-
seq experiments for DNA-binding proteins. Nat Biotechnol 26: 1351–1359. g
p
33. Author Contributions Conceived and designed the experiments: CDS. Performed the experi-
ments: CDS. Analyzed the data: CDS. Wrote the paper: CDS. Participated
in its design and coordination and helped to draft the manuscript: PB. PLoS ONE | www.plosone.org July 2010 | Volume 5 | Issue 7 | e11425 PLoS ONE | www.plosone.org 9 STAT1 on MER41 References Montgomery SB, Griffith OL, Sleumer MC, Bergman CM, Bilenky M, et al. (2006) ORegAnno: an open access database and curation system for literature-
derived promoters, transcription factor binding sites and regulatory variation. Bioinformatics 22: 637–640. characterization of participants. Soz Praventivmed 50: 245–263. 47. Su AI, Cooke MP, Ching KA, Hakak Y, Walker JR, et al. (2002) Large-scale
analysis of the human and mouse transcriptomes. Proc Natl Acad Sci U S A 99:
4465–4470. 23. Stormo GD (2000) DNA binding sites: representation and discovery. Bioinfor-
matics 16: 16–23. 48. Wormald S, Hilton DJ, Smyth GK, Speed TP (2006) Proximal genomic
localization of STAT1 binding and regulated transcriptional activity. BMC
Genomics 7: 254. 24. Schutz F, Delorenzi M (2008) MAMOT: hidden Markov modeling tool. Bioinformatics 24: 1399–1400. 49. Iseli C, Ambrosini G, Bucher P, Jongeneel CV (2007) Indexing strategies for
rapid searches of short words in genome sequences. PLoS ONE 2: e579. 25. Bailey TL, Elkan C (1994) Fitting a mixture model by expectation maximization
to discover motifs in biopolymers. Proceedings of the Second International PLoS ONE | www.plosone.org July 2010 | Volume 5 | Issue 7 | e11425 10
|
https://openalex.org/W3188234907
|
https://www.frontiersin.org/articles/10.3389/fimmu.2021.718845/pdf
|
English
| null |
Increased Expression of Extracellular Vesicles Is Associated With the Procoagulant State in Patients With Established Rheumatoid Arthritis
|
Frontiers in immunology
| 2,021
|
cc-by
| 7,827
|
Aleksandra Stojanovic 1, Mirjana Veselinovic 2, Yanan Zong 3, Vladimir Jakovljevic 4,5,
Iva Pruner 3 and Aleksandra Antovic 6,7* Aleksandra Stojanovic 1, Mirjana Veselinovic 2, Yanan Zong 3, Vladimir Jakovljevic 4,5,
Iva Pruner 3 and Aleksandra Antovic 6,7* Aleksandra Stojanovic 1, Mirjana Veselinovic 2, Yanan Zong 3, Vladimir Jakovljevic 4,5,
Iva Pruner 3 and Aleksandra Antovic 6,7* 1 Department of Pharmacy, Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Serbia, 2 Department of
Internal Medicine, Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Serbia, 3 Department of Molecular
Medicine & Surgery, Karolinska Institutet, Stockholm, Sweden, 4 Department of Physiology, Faculty of Medical Sciences,
University of Kragujevac, Kragujevac, Serbia, 5 Department of Human Pathology, I.M. Sechenov First Moscow State Medical
University, Moscow, Russia, 6 Department of Medicine, Division of Rheumatology, Karolinska Institutet, Stockholm, Sweden,
7 Academic Specialist Center, Center for Rheumatology, Stockholm Health Services, Stockholm, Sweden This study sought to identify different subpopulations of extracellular vesicles (EVs) in
plasma from female patients with established rheumatoid arthritis (RA) in relation to the
activation of coagulation and fibrin formation in these patients. Forty women were included
in the study, 20 patients and 20 age-matched healthy controls. The mean disease
duration in patients was 13.0 (5.0–25.0) years, with medium to high disease activity
despite ongoing treatment with low-dose prednisolone and methotrexate. There were no
differences between the investigated groups regarding the presence of traditional
cardiovascular risk factors. The concentration of phosphatidylserine-positive (PS+) EVs;
platelet (CD42a+), leucocyte (CD45+), monocyte (CD14+), and endothelial (CD144+)-
derived EVs; and EVs-expressing tissue factor (CD142+), P-selectin (CD62P+), and E-
selectin (CD62E+) were determined by flow cytometry analysis. Overall hemostasis
potential (OHP) was assessed to follow the hemostatic disturbances, including the
parameters for overall coagulation potential (OCP) and overall fibrinolytic potential
(OFP). Fibrin clot turbidity was measured together with clot lysis time, and scanning
electron microscopy was performed. Increased concentrations of PS+, CD42a+, CD142+,
CD45+, CD14+, and CD62P+ EVs were found in plasma from patients with RA compared
to healthy controls, and the concentrations of PS+, CD42a+, CD14+, and CD62P+ EVs
were positively correlated with the inflammatory parameters in RA patients. Positive
correlations were also found between the levels of PS+ and CD42a+ EVs and OCP as well
as between the levels of PS+, CD42a+, and CD62P+EVs and OHP. The levels of PS+,
CD42a+, CD14+, CD62P+, and CD62E+ EVs were negatively correlated with OFP. Aleksandra Stojanovic 1, Mirjana Veselinovic 2, Yanan Zong 3, Vladimir Jakovljevic 4,5,
Iva Pruner 3 and Aleksandra Antovic 6,7* Elevated levels of circulating EVs of different cell origins were found in patients with
established RA, in relation to the inflammatory burden and coagulation activation in
the disease. Edited by:
Andrea Picchianti-Diamanti,
Sapienza University, Italy Reviewed by:
Alessandra Stasi,
University of Bari Aldo Moro, Italy
Alessandra Bettiol,
University of Florence, Italy *Correspondence:
Aleksandra Antovic
aleksandra.antovic@ki.se Specialty section:
This article was submitted to
Autoimmune and
Autoinflammatory Disorders,
a section of the journal
Frontiers in Immunology
Received: 01 June 2021
Accepted: 19 July 2021
Published: 29 July 2021 Specialty section:
This article was submitted to
Autoimmune and
Autoinflammatory Disorders,
a section of the journal
Frontiers in Immunology Specialty section:
This article was submitted to
Autoimmune and
Autoinflammatory Disorders,
a section of the journal
Frontiers in Immunology Received: 01 June 2021
Accepted: 19 July 2021
Published: 29 July 2021 ORIGINAL RESEARCH
published: 29 July 2021
doi: 10.3389/fimmu.2021.718845 Keywords: rheumatoid arthritis, extracellular vesicles, hemostasis, inflammation, fibrin structure Citation: Stojanovic A, Veselinovic M, Zong Y,
Jakovljevic V, Pruner I and Antovic A
(2021) Increased Expression
of Extracellular Vesicles Is
Associated With the Procoagulant
State in Patients With Established
Rheumatoid Arthritis. Front. Immunol. 12:718845. doi: 10.3389/fimmu.2021.718845 Keywords: rheumatoid arthritis, extracellular vesicles, hemostasis, inflammation, fibrin structu July 2021 | Volume 12 | Article 718845 Frontiers in Immunology | www.frontiersin.org 1 Extracellular Vesicles in RA Patients Stojanovic et al. INTRODUCTION correlated with the presence of traditional cardiovascular risk
factors (diabetes mellitus, hypertension, dyslipidemia and obesity)
in a cohort of 114 RA patients, and EVs isolated from RA patients
were able to promote endothelial activation in vitro (19). Rheumatoidarthritis(RA)isachronic,inflammatory,autoimmune
disease causing synovitis and destructive arthritis and is
accompanied by out-of-joint disease manifestations, a strong
systemic inflammatory response with accelerated development of
atherosclerosisandshortenedlifeexpectancyandassuchrepresents
a significant burden for both individuals and society (1–5). The
mostcommononsetofillnessisintheforties(6),withasignificantly
higher disease activity in the female population (7). Patients with
RA have high prevalence of cardiovascular disease (CVD) as well as
an increased risk of developing fatal cardiovascular events such as
acute myocardial infarction, stroke, and heart failure (8, 9). Still, the procoagulant effect of EVs has not previously been
exploredinpatientswithRA.Thisisofparticularinterestinpatients
with long-lasting disease and accumulated inflammatory burden
leadingtotheactivationofcoagulation,diminishedfibrinolysis,and
accelerated prothrombotic condition. Considering the above
observations, we aimed to identify different subpopulations of
EVs in the plasma of female patients with established RA in
relation to the hemostatic disturbances associated with chronic
systemic inflammation in this disease. Still, the procoagulant effect of EVs has not previously been
exploredinpatientswithRA.Thisisofparticularinterestinpatients
with long-lasting disease and accumulated inflammatory burden
leadingtotheactivationofcoagulation,diminishedfibrinolysis,and
accelerated prothrombotic condition. Considering the above
observations, we aimed to identify different subpopulations of
EVs in the plasma of female patients with established RA in
relation to the hemostatic disturbances associated with chronic
systemic inflammation in this disease. The pathogenesis of RA is complex and comprises interactions
between genetics, epigenetic modifications, and environmental
factors such as smoking, all of which contribute to the production
of specific autoantibodies against citrullinated proteins (ACPAs),
systemic inflammatory response, and joint destruction. Study Participants Twenty age and sex-matched healthy women (mean age 52.55 ±
7.27 years) were included in the study as healthy controls (HC). None of the women included in the study were taking oral
contraceptives or receiving hormone replacement treatment. g
y
y
Higher proportions of leucocyte-derived EVs (LEVs) have been
found in the plasma of RA patients compared to the plasma of
patients with osteoarthritis (OA) and healthy controls (HCs), while
increased levels of LEVs and monocyte and T-cell–derived EVs
werealso presentinthesynovialfluidofpatientswithRAcompared
to OA patients (12). Biro E et al. considered the role of complement
in the pathogenesis of RA and detected LEVs expressing the
complement components C1q, C4, and/or C3 in the synovial
fluid of RA patients, but plasma levels of LEVs expressing
complement were much lower in both patients with RA and in
controls (17). Elevated levels of EVs expressing C1q were found in
patients with early RA and remained increased even during the
combination therapy with prednisolone, methotrexate, and
sulfasalazine and despite improved disease activity as measured
by DAS28 scores (18). Additionally, increased EV amounts Written informed consent was obtained from all participants,
andthestudyprotocolwasapprovedbytheEthicsCommitteeofthe
Clinical Center Kragujevac prior to the onset of the study. The
investigation was conducted in accordance with the principles
outlined in the Declaration of Helsinki and principles of Good
Clinical Practice. Study Participants Recently, the role of microparticles was implicated in the
pathogenesis of RA. Microparticles, also called extracellular
vesicles (EVs), are small membrane-coated vesicles 0.1–1.0 µm
in diameter that are released from various cells during cell
activation and apoptosis. Depending on the cell of origin, EVs
incorporate nuclear, cytoplasmic, and membrane molecules as
they detach from the cells, and they express cellular antigens on
their surface (10). EVs can be a source of autoantigens and can
induce the formation of immune complexes or may be involved
in the transfer of miRNA and inflammatory cytokines (11, 12). EVs also have important procoagulant properties based on the
availability of phosphatidylserine (PS) exposed on the surface
after stimulation (13). Twenty women with established RA referred to the outpatient clinic
of the Department of Rheumatology, Clinical Centre Kragujevac,
Serbia, were included in the study (mean age 51.85 ± 9.43 years). These patients were previously included as part of a larger study
investigating hemostatic disturbances in women with RA (20). RA
was diagnosed according to the classification criteria of the American
College of Rheumatology (ACR)/European League Against
Rheumatism (EULAR) 2010 (21). The exclusion criteria comprised
a history of diabetes mellitus, malignancy, or inflammatory bowel
disease, liver or renal insufficiency, previous cerebrovascular or
cardiovascular disorders (including inherited thrombophilia,
antiphospholipid syndrome, and hyperhomocysteinemia), or
venous thromboembolism. A pivotal study revealed increased levels of platelet-derived EVs
(PEVs) inplasmafromRApatients, and these levelscorrelated with
disease activity (14), while Boilard et al. demonstrated the presence
of a large number of PEVs in the synovial fluid of RA patients (15). This might be a surprising finding because the origin of PEVs in the
joint spaces is not known, thus suggesting platelet activation in the
joint or the transit of PEVs. Stimulation of the collagen receptor
glycoprotein VI on platelets seems to be the key trigger for the
collagen-induced generation of PEVs in arthritis pathophysiology
(15).However, some data suggest that EVs inthe joint can originate
from granulocytes or monocytes (16). RA assessments included a detailed medical history, the presence
of extra-articular disease, current disease activity assessed by the 28-
point disease activity score (DAS28) (22), and physical function
using the Health Assessment Questionnaire (HAQ) (23). All
current medications were recorded. Additionally, at the time of
blood sampling the patients did not receive any anticoagulants,
antithrombotic agents (acetylsalicylic acid), or non-steroidal anti-
inflammatory drugs. Frontiers in Immunology | www.frontiersin.org RESULTS Characteristics of the Study Population
The mean disease duration in patients was 13.0 ± 6.6 years, and
disease activity was medium to high (DAS28 was 4.1 ± 1.2) at the
momentofbloodsampling.ThemeanHAQvaluewas1.2±0.2,and
the majority of patients were rheumatoid factor positive (n = 18;
90%) and ACPA positive (n = 20; 100%). All patients were treated
with methotrexate (15–25 mg per week) and prednisolone (≤10 mg
per day), and only two patients (10%) were in remission
(DAS28<2.5). Patients were not previously treated with biologic Blood Sampling Blood was collected in tubes containing 0.129 M sodium citrate
(BD Vacutainer Blood Collection System) using 21-gauge
needles (BD Vacutainer needles). Platelet-poor plasma was
obtained within 60 min of sampling by centrifugation at 2,000 ×
g for 15 min at room temperature, then divided into aliquots and
stored frozen at –70°C until further analysis. July 2021 | Volume 12 | Article 718845 Frontiers in Immunology | www.frontiersin.org 2 Extracellular Vesicles in RA Patients Stojanovic et al. corresponds to the “clotting time”) to the midpoint of the
maximum turbid-to-clear transition. Determination of Overall Hemostatic Potential We employed a modification of the assay described by He et al. (25) in order to assess overall hemostatic potential (OHP) in
plasma. Absorbance (Abs) at 405 nm was measured every 12
seconds for 60 minutes, and the area under the curve was
calculated by summation of the Abs values (Abs-sum) and
expressed as the OHP value. Two additional parameters were
also analyzed – the overall coagulation potential (OCP),
determined as the area under the fibrin aggregation curve
obtained without the addition of tissue plasminogen activator
(t-PA), and the overall fibrinolysis potential (OFP), calculated as
the difference between the two areas as OFP (%) = ((OCP −
OHP)/OCP) × 100. The intra- and inter-assay coefficients of
variation for OHP were 1.6% and 6.8% and for OCP were 1.2%
and 5.7%, respectively. The detailed protocol was previously
described (20). Routine Laboratory Analysis y
y
Laboratory analyses of C-reactive protein (CRP) (turbidimetric
method, Beckman Coulter AU680 analyser), erythrocyte
sedimentation rate (ESR) (Westergren method, Vacuette ESR
analyser), fibrinogen concentration (Clauss method, ACL TOP
analyser by Instrumentation Laboratory), lipid profile (cholesterol,
triglycerides,HDL,andLDL,allbyBeckmanCoulterAU680analyser),
rheumatoid factor (turbidimetric method, Beckman Coulter AU680
analyser), and ACPA (Roche electrochemiluminescence
immunoassay, Cobas e411 analyser), were performed at the Central
Laboratory of the Clinical Center Kragujevac. y
y
Laboratory analyses of C-reactive protein (CRP) (turbidimetric
method, Beckman Coulter AU680 analyser), erythrocyte
sedimentation rate (ESR) (Westergren method, Vacuette ESR
analyser), fibrinogen concentration (Clauss method, ACL TOP
analyser by Instrumentation Laboratory), lipid profile (cholesterol,
triglycerides,HDL,andLDL,allbyBeckmanCoulterAU680analyser),
rheumatoid factor (turbidimetric method, Beckman Coulter AU680
analyser), and ACPA (Roche electrochemiluminescence
immunoassay, Cobas e411 analyser), were performed at the Central
Laboratory of the Clinical Center Kragujevac. Scanning Electron Microscopy g
py
The clots formed during fibrin generation for the determination
of OCP were washed with PBS (phosphate-buffered saline)
solution and fixed in 2.5% glutaraldehyde in Hepes-buffered
saline for 60 min at room temperature and stored at 4°C. Samples
were analyzed under an Ultra 55 field emission scanning electron
microscope (Carl Zeiss, Oberkochen, Germany) at 3 kV. The
detailed protocol was previously described (20). EVs were measured by flow cytometry on a BD FACSCanto™
instrument. The MV-gate was determined using Megamix plus
beads FSC (BioCytex, Marseille, France), which is a mix of beads
with diameters of 0.1, 0.3, 0.5, and 0.1 µm. EVs were defined as
vesicles <1.0 µm in size and positive for lactadherin. Conjugate
isotype-matched immunoglobulins (IgG1-FITC, IgG1-PE, and
IgG1-APC) with no reactivity against human antigens were used
as negative controls to define the positive and negative gates. The
absolute number of EVs was calculated by means of the following
formula: Concentration (ml) = (Events reading × 550)/(44 × 20),
where 550 ml is the total volume of sample in the tube analyzed,
44 ml is the volume of the analyzed sample over 90 s, and 20 ml is
the volume of the plasma sample added in the tube (24). The
concentration of EVs is expressed as 106 EVs/l, and the intra and
interassay coefficients of variation for EV measurements were
less than 9%. Flow Cytometry Analyses of EVs Subsequently, 20 µl of the supernatant was incubated for 20 min in
the dark with lactadherin-FITC (BD Biosciences, USA) together
with CD42a-PE (PEVs; BD Biosciences, USA), CD14-PE
[Monocyte EVs (MoEVs); BD Biosciences, USA], CD45-APC
[Leucocyte EVs (LEVs); BD Biosciences, USA), CD62P-PE (P-
selectin, BD Biosciences, USA), CD62E-PE (Endothelial EVs – E-
selectine;BDBiosciences,USA);CD142-PE (Tissuefactor(TF), BD
Biosciences, USA), CD144-PE (Endothelial EVs; BD
Biosciences, USA). Scanning Electron Microscopy
The clots formed during fibrin generation for the determination
of OCP were washed with PBS (phosphate-buffered saline)
solution and fixed in 2.5% glutaraldehyde in Hepes-buffered
saline for 60 min at room temperature and stored at 4°C. Samples
were analyzed under an Ultra 55 field emission scanning electron
microscope (Carl Zeiss, Oberkochen, Germany) at 3 kV. The
detailed protocol was previously described (20). Statistical Analysis All data were analyzed using SPSS 20.0 (IBM Corp. Released
2011), GraphPad Prism 5 (Version for Windows, GraphPad
Software, La Jolla California, USA), and FlowJo software 8.7.1
(Treestar, Ashland, OR). The results are expressed as means (SD)
or median (IQR) depending on the data type and distribution. Distribution of the data was checked by the Shapiro–Wilk test. Independent samples t-tests (parametric) and Mann–Whitney
U-tests (non-parametric) were used to assess the differences in
estimated variables between groups. A p-value <0.05 was
regarded as statistically significant. Correlation between
variables was examined using Spearman correlation analysis. Global Hemostatic Assays y
Determination of Overall Hemostatic Potential Isolation of EVs Platelet-poor plasma was thawed in a water bath for
approximately 5 min (37°C) and thereafter centrifuged at 2,000 ×
g for 20 min at room temperature. The supernatant was then re-
centrifuged at 13,000 g for 2 min at room temperature. The
obtained supernatant was used for further analysis. Analysis of Fibrin Clot Formation
Fibrin clot density was assessed with the turbidimetric clotting
assay according to the method described by Carter et al. (26). The
turbidimetric curve for determination of OCP was used to assess
the maximum absorbance (Max Abs) as a measure of the clot
density and defined as the increase in Abs from baseline to the
maximum value (20). Determination of Clot Lysis Time CLT was determined based on the fibrin aggregation curve for
the determination of OHP and was defined as the time from the
midpoint of the clear-to-maximum-turbid transition (which July 2021 | Volume 12 | Article 718845 Frontiers in Immunology | www.frontiersin.org 3 Extracellular Vesicles in RA Patients Stojanovic et al. TABLE 2 | Parameters of global hemostatic assays in the study population. Parameters
Healthy controls
RA patients
p value
OHP (Abs-sum)
345.0 ± 42.8
390.4 ± 60.2
p = 0.003
OCP (Abs-sum)
126.5 ± 28.1
166.3 ± 49.6
p = 0.009
OFP (%)
63.4 ± 6.6
58.0 ± 8.6
p = 0.032
Max Abs
1.6 ± 0.3
1.8 ± 0.2
p = 0.037
CLT (sec)
21.5 ± 3.7
25.1 ± 4.4
p = 0.008
The values are expressed as means ± SD. OHP, Overall hemostasis potential; OCP,
Overall coagulation potential; OFP, Overall fibrinolytic potential; Max Abs, increase in
absorbance from baseline to maximum value; CLT, clot lysis time. TABLE 2 | Parameters of global hemostatic assays in the study population. agents. Three patients had extra-articular manifestations in the
form of rheumatoid nodules on the elbows and the small joints of
the hands. There were no differences between the HC and RA patients
regarding the presence of traditional CVD risk factors or
regarding lipid profile. Patients with RA had higher CRP, ESR and fibrinogen levels
compared to HC. Demographic and clinical characteristics of the
participants as well as the presence of traditional CVD risk
factors and laboratory parameters are presented in Table 1. stratified analyses according to the daily corticosteroid dosage
have not shown significant differences in the levels of
investigated EVs. stratified analyses according to the daily corticosteroid dosage
have not shown significant differences in the levels of
investigated EVs. Correlations As presented in Table 3 and Figure 1, the concentration of PS+
EVs was significantly higher in RA patients compared to HC. Furthermore, PEVs, LEVs, MoEVs and EVs expressing TF and
P-selectin were significantly higher in RA patients. EVs of
endothelial origin (CD144+ or CD62E+) were higher in RA
patients, but the difference was not statistically significant. The The correlations between the levels EVs and inflammatory
parameters ESR and CRP as well as the parameters of the
global hemostatic assays are presented in Table 4. Analysis of Clot Structure Scanning electron microscopy showed dense fibrin structures in
the plasma from an RA patient compared to the control sample. The clot from the RA patient was made of thinner fibers that
were tightly packed into the network with smaller intrinsic pores
and thus less susceptible to fibrinolysis (Figure 3), and this was
similar to our previous findings of fibrin clots in women with RA
in regard to the menopausal status (20). TABLE 1 | Clinical characteristics and laboratory parameters of the study
population. TABLE 1 | Clinical characteristics and laboratory parameters of the study
population. population. Subjects characteristics
Healthy controls
RA patients
p value
Number of patients
20
20
Average age (years)
52.5 ± 7.2
51.8 ± 9.4
NS
BMI (kg/m2)
25.3 ± 3.5
25.6 ± 5.2
NS
Disease duration (years)
NA
13.0 ± 6.6
/
DAS28
NA
4.1± 1.2
/
HAQ
NA
1.2 ± 0.2
/
RF positive, n (%)
NA
18 (90)
/
ACPA positive, n (%)
NA
20 (100)
/
Ongoing treatment
Prednisolone 10mg, n(%)
NA
12 (60)
Prednisolone 5mg, n(%)
NA
8 (40)
Methotrexate 15 mg, n(%)
NA
7 (35)
Methotrexate 20 mg, n(%)
NA
11 (55)
Methotrexate 25 mg, n(%)
NA
2 (10)
Smokers (n,%)
Current smokers
10 (50)
7 (35)
NS
Non-smokers
8 (40)
12 (60)
NS
Past smokers
2 (10)
1 (5)
NS
Cholesterol (mmol/L)
6.2 ± 1.1
5.8 ± 1.1
NS
Triglycerides (mmol/L)
1.4 ± 0.7
1.3 ± 0.5
NS
HDL (mmol/L)
1.56 ± 0.28
1.44 ± 0.24
NS
LDL (mmol/L)
4.0 ± 1.0
3.8 ± 1.1
NS
ESR (mm/h)
10.7 ± 8.5
29.0 (7.0-56.0)
p < 0.001
CRP (mg/L)
1.9 ± 1.0
6.8 (0.8-56.2)
p < 0.001
Fibrinogen (g/L)
3.1 ± 0.6
3.9 ± 0.5
p < 0.001
The values are expressed as means ± SD or median (IQR). BMI, body mass index; DAS28,
Disease Activity Score 28; HAQ, Health Assessment Questionnaire; RF, rheumatoid
factor; ACPA, citrullinated protein antigen; HDL, High-density lipoprotein; LDL, Low-
density lipoprotein; ESR, Erythrocyte sedimentation rate; CRP, C-reactive protein; NA, not
applicable; NS, not significant. Subjects characteristics
Healthy controls
RA patients
p value Measurementofthefiberthicknessoftherepresentativesamples
was performed in five different areas, and the mean value of 10
fibers/area was used as the final measure of fiber thickness in these
samples. Thinner fibers were found in the patient compared with
control (136 nm ± 49 nm vs 157.0 ± 56.0 nm). Global Hemostatic Parameters As presented in Table 2, OCP (Abs-sum) and OHP (Abs-sum)
were significantly higher, while OFP (%) was significantly lower
in RA patients compared to HC. Parameters of fibrin clotting
showed higher Max Abs values and longer CLT in RA patients
indicating increased clot turbidity and diminished fibrinolysis in
these patients. Representative Samples p
p
Representative dot-plots for PS+EVs (Lactadherin+ EVs)
regardless of cellular origin, together with PEVs (CD42a+) as
the most common EVs, are presented on Figure 2. DISCUSSION EVs, extracellular vesicles; Ps, phosphatidylserine; TF, tissue factor; PEVs,
platelet-derived EVs; LEVs, leucocyte-derived EVs; MoEVs, monocyte-derived EVs; EEVs, endothelial EVs. *p < 0.05; **p < 0.01; ***p < 0.001; ns, non-significant;
white: healthy controls; black: rheumatoid arthritis. FIGURE 1 | Distribution of different subtypes of EVs in HCs and patients with RA. EVs, extracellular vesicles; Ps, phosphatidylserine; TF, tissue factor; PEVs,
platelet-derived EVs; LEVs, leucocyte-derived EVs; MoEVs, monocyte-derived EVs; EEVs, endothelial EVs. *p < 0.05; **p < 0.01; ***p < 0.001; ns, non-significant;
white: healthy controls; black: rheumatoid arthritis. homogenous group of RA patients in comparison to strictly
matched control subjects. In line with previous studies, our results verify that the majority
of circulating EVs in RA patients are of platelet origin (14, 29, 33),
reflecting platelet activation in RA as an essential part of the
inflammatory reaction. PEVs are involved in the interactions
between platelets and inflammatory cells and in production of
pro-inflammatory cytokines (31). Previously, a direct correlation
was found between the levels of circulating PEVs and disease
activity in RA patients (14, 29, 33). We were not able to confirm
this association, probably due to the small number of investigated
patients. Still, there was clear association of circulating PEVs with
theinflammatoryparameters,aswellastheparametersofactivation
of coagulation and impaired fibrinolysis in our patients. As an
additional marker of platelet activation, we noticed increased
expression of P-selectin on circulating EVs in plasma from RA
patients. P-selectin mediates the interaction between platelets and
neutrophils (11) and may be a sign of ongoing platelet activation in
RA, even if the disease is clinically silent (34). Amplified expression
of P-selectin was also found in the synovial fluid of RA patients,
though not as high as in the circulation (33). While the formation of EVs is a physiological response to cell
activation or cell death, a dramatic increase in circulating EVs has
been detected in conditions associated with inflammatory states of
different severity and different prothrombotic conditions (27–29). Identification of EV origin is vital because it indicates the dominant
cell types involved in the pathogenesis of these disorders (14, 18, 30,
31).Severalstudieshavetriedto elucidatetheroleofcirculatingEVs
as well as EVs detected in the synovial fluid in the pathogenesis of
RA, as reviewed in Boilard et al. (32). We have shown elevated levels of EVs expressing PS
irrespective of the cell origin in plasma from patients with RA. Frontiers in Immunology | www.frontiersin.org DISCUSSION EVs, extracellular vesicles; Ps, phosphatidylserine; TF, tissue factor; PEVs,
platelet-derived EVs; LEVs, leucocyte-derived EVs; MoEVs, monocyte-derived EVs; EEVs, endothelial EVs. *p < 0.05; **p < 0.01; ***p < 0.001; ns, non-significant;
white: healthy controls; black: rheumatoid arthritis. TABLE 3 | The concentration of different subtypes of EVs in healthy controls and rheumatoid arthritis patients. EV concentration (106 EVs/l)
Healthy controls (n = 20)
Rheumatoid arthritis patients (n = 20)
p-value
PS+ EVs
934.4 (695.6–1479.0)
1918.0 (950.0.5–3822.0)
p = 0.01
PEVs (CD42a+)
218.1 (141.3–335.0)
620.9 (202.2–1111.0)
p = 0.02
TF+ EVs (CD142+)
37.5 (26.2–48.7)
50.3 (35.0–117.8)
p = 0.03
LEVs (CD45+)
53.4 (43.4–62.2)
83.1 (62.2–145.3)
p = 0.008
MoEVs (CD14+)
74.7 (66.2–94.7)
320.8 (235.0–527.5)
p < 0.001
P-selectin (CD62P+)
12.0 (10.0–19.4)
20.0 (14.3–28.7)
p = 0.008
EEVs (CD144+)
35.0 (25.0–47.5)
36.2 (26.8–72.2)
NS
E-selectin (CD62E+)
33.1 (22.5–52.5)
60.3 (18.7–106.6)
NS
The results are expressed as median (IQR). NS, non-significant difference between the groups; EVs, extracellular vesicles; PS, phosphatidylserine; PEVs, platelet-derived EVs; LEVs,
leucocyte-derived EVs; MoEVs, monocyte-derived EVs; EEVs, endothelial EVs. TABLE 3 | The concentration of different subtypes of EVs in healthy controls and rheumatoid arthritis patients. EV concentration (106 EVs/l)
Healthy controls (n = 20)
Rheumatoid arthritis patients (n = 20)
p-value
PS+ EVs
934.4 (695.6–1479.0)
1918.0 (950.0.5–3822.0)
p = 0.01
PEVs (CD42a+)
218.1 (141.3–335.0)
620.9 (202.2–1111.0)
p = 0.02
TF+ EVs (CD142+)
37.5 (26.2–48.7)
50.3 (35.0–117.8)
p = 0.03
LEVs (CD45+)
53.4 (43.4–62.2)
83.1 (62.2–145.3)
p = 0.008
MoEVs (CD14+)
74.7 (66.2–94.7)
320.8 (235.0–527.5)
p < 0.001
P-selectin (CD62P+)
12.0 (10.0–19.4)
20.0 (14.3–28.7)
p = 0.008
EEVs (CD144+)
35.0 (25.0–47.5)
36.2 (26.8–72.2)
NS
E-selectin (CD62E+)
33.1 (22.5–52.5)
60.3 (18.7–106.6)
NS
The results are expressed as median (IQR). NS, non-significant difference between the groups; EVs, extracellular vesicles; PS, phosphatidylserine; PEVs, platelet-derived EVs; LEVs,
leucocyte-derived EVs; MoEVs, monocyte-derived EVs; EEVs, endothelial EVs. concentration of different subtypes of EVs in healthy controls and rheumatoid arthritis patients. FIGURE 1 | Distribution of different subtypes of EVs in HCs and patients with RA. EVs, extracellular vesicles; Ps, phosphatidylserine; TF, tissue factor; PEVs,
platelet-derived EVs; LEVs, leucocyte-derived EVs; MoEVs, monocyte-derived EVs; EEVs, endothelial EVs. *p < 0.05; **p < 0.01; ***p < 0.001; ns, non-significant;
white healthy controls black rheumatoid arthritis FIGURE 1 | Distribution of different subtypes of EVs in HCs and patients with RA. DISCUSSION We determined the presence of circulating EVs in relation to
hemostatic disturbances in women with established RA,
indicating the presence of a hypercoagulable state in these
patients. Despite treatment, the patients with RA included in our
studypresentedwithongoinginflammatoryactivitycontributingto
the extensive production of circulating EVs of platelet, leucocyte,
and monocyte origin as well as increased expression of PS, TF, and
P-selectin on the surface of EVs. In addition, amplified fibrin
formation together with increased clot turbidity and diminished
fibrinolysis was confirmed in these patients as measured by the
global hemostatic parameters OCP, OHP, Max Abs, and OFP,
respectively (20). We postulate that EVs play an important role in
the delicate interaction between inflammatory processes and the
activation of coagulation in the course of RA. The major advantage
ofour study is the investigation ofcirculatingEVs ofdifferentorigin
in relation to hemostatic and inflammatory parameters in a July 2021 | Volume 12 | Article 718845 Frontiers in Immunology | www.frontiersin.org 4 Extracellular Vesicles in RA Patients Stojanovic et al. homogenous group of RA patients in comparison to strictly
In line with previous studies, our results verify that the majority
FIGURE 1 | Distribution of different subtypes of EVs in HCs and patients with RA. EVs, extracellular vesicles; Ps, phosphatidylserine; TF, tissue factor; PEVs,
platelet-derived EVs; LEVs, leucocyte-derived EVs; MoEVs, monocyte-derived EVs; EEVs, endothelial EVs. *p < 0.05; **p < 0.01; ***p < 0.001; ns, non-significant;
white: healthy controls; black: rheumatoid arthritis. TABLE 3 | The concentration of different subtypes of EVs in healthy controls and rheumatoid arthritis patients. EV concentration (106 EVs/l)
Healthy controls (n = 20)
Rheumatoid arthritis patients (n = 20)
p-value
PS+ EVs
934.4 (695.6–1479.0)
1918.0 (950.0.5–3822.0)
p = 0.01
PEVs (CD42a+)
218.1 (141.3–335.0)
620.9 (202.2–1111.0)
p = 0.02
TF+ EVs (CD142+)
37.5 (26.2–48.7)
50.3 (35.0–117.8)
p = 0.03
LEVs (CD45+)
53.4 (43.4–62.2)
83.1 (62.2–145.3)
p = 0.008
MoEVs (CD14+)
74.7 (66.2–94.7)
320.8 (235.0–527.5)
p < 0.001
P-selectin (CD62P+)
12.0 (10.0–19.4)
20.0 (14.3–28.7)
p = 0.008
EEVs (CD144+)
35.0 (25.0–47.5)
36.2 (26.8–72.2)
NS
E-selectin (CD62E+)
33.1 (22.5–52.5)
60.3 (18.7–106.6)
NS
The results are expressed as median (IQR). NS, non-significant difference between the groups; EVs, extracellular vesicles; PS, phosphatidylserine; PEVs, platelet-derived EVs; LEVs,
leucocyte-derived EVs; MoEVs, monocyte-derived EVs; EEVs, endothelial EVs. FIGURE 1 | Distribution of different subtypes of EVs in HCs and patients with RA. DISCUSSION The phospholipid membranes of EVs containing PS represent an
adequate platform for the activation of coagulation processes
leading to increased thrombin and fibrin formation, as measured
by OCP and OHP (28, 29). Further, we present the association
between the intensity of inflammation in RA and the
concentration of released PS+EVs. Thus, the negatively charged
phospholipid membrane of EVs might play an important role in
the interactions between the inflammatory state and
procoagulant condition in the circulation of RA patients. Moreover, circulating PEVs have the ability to incorporate into
the fibrin clots (35). We have recently confirmed the close
interaction between PEVs and fibrin fibers, particularly at July 2021 | Volume 12 | Article 718845 5 Extracellular Vesicles in RA Patients Stojanovic et al. A
B
C
D
FIGURE 2 | Representative samples of PS+EVs and PEVs. EVs positive for lactadherin (PS+EVs) in a control sample (A) and RA patient (B). Platelet-derived EVs in
a control sample (C) and RA patient (D). EVs, extracellular vesicles. B A D D C D C FIGURE 2 | Representative samples of PS+EVs and PEVs. EVs positive for lactadherin (PS+EVs) in a control sample (A) and RA patient (B). Platelet-derived EVs in
a control sample (C) and RA patient (D). EVs, extracellular vesicles. FIGURE 2 | Representative samples of PS+EVs and PEVs. EVs positive for lactadherin (PS+EVs) in a control sample (A) and RA
a control sample (C) and RA patient (D). EVs, extracellular vesicles. TABLE 4 | Correlations between the levels of EVs and inflammatory parameters and the parameters of the global haemostatic assays. EVs, extracellular vesicles; PS, phosphatidylserine; TF, tissue factor; PEVs, platelet-derived EVs; LEVs, leucocyte-derived EVs; MoEVs, monocyte-derived EVs; EEVs, endothelial EVs;
OHP, Overall hemostasis potential; OCP, Overall coagulation potential; OFP, Overall fibrinolytic potential; Max Abs, increase in absorbance from baseline to maximum value. DISCUSSION B A A D C C FIGURE 3 | Scanning electron microscopic images of representative fibrin clots. HC (A, C) and RA patient (B, D). The magnification 1 mm was used for (A, B) and
300 nm for (C, D). HC, healthy control. finding of increased TF expression on circulating EVs in RA
patients is not surprising. Previously, higher proportions of
MoEVs were reported in RA patients with high disease activity
compared to patients in remission (39), and we confirmed the
association with the inflammatory markers in our cohort. We
believe that the elevated concentrations of PEVs together with
MoEVs and EVs expressing P-selectin and TF could be potential
biomarkers for the inflammatory and procoagulant activity
in RA. branch points and junctions (24). This finding may suggest
intensified fibrin formation around the surface of PEVs,
following the activation of platelets and the propagation phase
of thrombin generation. Denser fibrin clots formed upon extensive
platelet activation and augmented expression of PEVs in RA might
therefore be revealed by the increased fibrin turbidity as measured
by the Max Abs in our study. Scanning electron microscope
pictures of denser fibrin composed of thinner fibers and with
smaller intrinsic pores in RA patients confirm this finding, while
decreased OFP together with prolonged CLT reflects the reduced
fibrinolytic capacity as a consequence. Formatin of fibrin clots
with a more prothrombotic phenotype in the presence of PEVs
may be in agreement with the work of Knijff-Dutmeret et al. suggesting a possible association between PEVs and the
development of CVD in patients with RA (14). Apart from circulating EVs, synovial fluid obtained from the
joints of RA patients contains EVs derived from monocytes,
granulocytes, T-cells, B-cells, and even platelets (12, 15, 16, 40–
43). The major disadvantage of our study is the lack of
investigation of EVs in the synovial fluid. The majority of our
patients presented with medium-high disease activity as
measured by DAS-28 score, but a sufficient amount of synovial
fluid was not available for sampling during the study period. Elevated levels of circulating MoEVs were also found in the
RA patients. The interactions between platelets and monocytes
are well documented, indicating the accelerated generation of
TFs by activated monocytes and the particularly important role
of PEVs and MoEVs in this process (36–38). Therefore, our fluid was not available for sampling during the study period. July 2021 | Volume 12 | Article 718845 DISCUSSION Parameters
CRP
ESR
OCP
OHP
OFP
Max Abs
CLT
PS+EVs
p = 0.048
r = 0.32
p = 0.009
r = 0.41
p = 0.013
r = 0.39
p = 0.001
r = 0.51
p = 0.006
r = –0.43
p = 0.001
r = 0.511
p = 0.002
r = 0.467
PEVs (CD42a+)
p = 0.031
r = 0.34
p = 0.007
r = 0.42
p = 0.039
r = 0.33
p = 0.002
r = 0.47
p = 0.006
r = –0.43
p = 0.004
r = 0.441
p = 0.006
r = 0.426
TF+EVs (CD142+)
p > 0.05
p > 0.05
p > 0.05
p > 0.05
p > 0.05
p > 0.05
p > 0.05
LEVs (CD45+)
p > 0.05
p > 0.05
p > 0.05
p > 0.05
p > 0.05
p = 0.024
r = 0.355
p = 0.049
r = 0.313
MoEVs (CD14+)
p = 0.001
r = 0.51
p = 0.005
r = 0.44
p > 0.05
p > 0.05
p = 0.031
r = –0.34
p = 0.002
r = 0.484
p = 0.005
r = 0.439
P-selectin (CD62P+)
p = 0.015
r = 0.38
p = 0.004
r = 0.47
p > 0.05
p = 0.014
r = 0.39
p = 0.015
r = –0.38
p > 0.05
p = 0.007
r = 0.420
EEVs (CD144+)
p > 0.05
p > 0.05
p > 0.05
p > 0.05
p > 0.05
p > 0.05
p > 0.05
E-selectin (CD62E+)
p > 0.05
p > 0.05
p > 0.05
p > 0.05
p = 0.041
r = –0.32
p > 0.05
p = 0.028
r = 0.349
EVs, extracellular vesicles; PS, phosphatidylserine; TF, tissue factor; PEVs, platelet-derived EVs; LEVs, leucocyte-derived EVs; MoEVs, monocyte-derived EVs; EEVs, endothelial EVs;
OHP, Overall hemostasis potential; OCP, Overall coagulation potential; OFP, Overall fibrinolytic potential; Max Abs, increase in absorbance from baseline to maximum value. 4 | Correlations between the levels of EVs and inflammatory parameters and the parameters of the global haemostatic assays. Frontiers in Immunology | www.frontiersin.org July 2021 | Volume 12 | Article 718845 6 Extracellular Vesicles in RA Patients Stojanovic et al. A
B
C
D
FIGURE 3 | Scanning electron microscopic images of representative fibrin clots. HC (A, C) and RA patient (B, D). The magnification 1 mm was used for (A, B) and
300 nm for (C, D). HC, healthy control. Frontiers in Immunology | www.frontiersin.org REFERENCES Atherosclerosis in Rheumatoid Arthritis. Immunol Res (2018) 66:655–62. doi: 10.1007/s12026-018-9053-0 1. Angelotti F, Parma A, Cafaro G, Capecchi R, Alunno A, Puxeddu I. One Year
in Review 2017: Pathogenesis of Rheumatoid Arthritis. Clin Exp Rheumatol
(2017) 35:368–78. 12. Michael BNR, Kommoju V, Kavadichanda Ganapathy C, Negi VS. Characterization of Cell-Derived Microparticles in Synovial Fluid and
Plasma of Patients With Rheumatoid Arthritis. Rheumatol Int (2019)
39:1377–87. doi: 10.1007/s00296-019-04337-1 2. CrossM,SmithE, HoyD,Carmona L,WolfeF,VosT,etal. TheGlobalBurdenof
Rheumatoid Arthritis: Estimates From the Global Burden of Disease 2010 Study. Ann Rheum Dis (2014) 73:1316–22. doi: 10.1136/annrheumdis-2013-204627 13. Connor DE, Exner T, Ma DD, Joseph JE. Detection of the Procoagulant
Activity of Microparticle-Associated Phosphatidylserine Using XACT. Blood
Coagul Fibrinolysis (2009) 20:558–64. doi: 10.1097/MBC.0b013e32832ee915 3. Dye JR, Ullal AJ, Pisetsky DS. The Role of Microparticles in the Pathogenesis
of Rheumatoid Arthritis and Systemic Lupus Erythematosus. Scand J
Immunol (2013) 78:140–8. doi: 10.1111/sji.12068 14. Knijff-Dutmer EA, Koerts J, Nieuwland R, Kalsbeek-Batenburg EM, van de
Laar MA. Elevated Levels of Platelet Microparticles are Associated With
Disease Activity in Rheumatoid Arthritis. Arthritis Rheum (2002) 46:1498–
503. doi: 10.1002/art.10312 4. Smolen JS, Aletaha D, McInnes IB. Rheumatoid Arthritis. Lancet (2016)
388:2023–38. doi: 10.1016/S0140-6736(16)30173-8 5. Talsania M, Scofield RH. Menopause and Rheumatic Disease. Rheum Dis Clin
North Am (2017) 43:287–302. doi: 10.1016/j.rdc.2016.12.011 15. Boilard E, Nigrovic PA, Larabee K, Watts GF, Coblyn JS, Weinblatt ME, et al. Platelets Amplify Inflammation in Arthritis Via Collagen-Dependent Microparticle
Production. Science (2010) 327:580–3. doi: 10.1126/science.1181928 6. Oliver JE, Silman AJ. Why are Women Predisposed to Autoimmune
Rheumatic Diseases? Arthritis Res Ther (2009) 11:252. doi: 10.1186/ar2825 16. Berckmans RJ, Nieuwland R, Kraan MC, Schaap MC, Pots D, Smeets TJ, et al. Synovial Microparticles From Arthritic Patients Modulate Chemokine and
Cytokine Release by Synoviocytes. Arthritis Res Ther (2005) 7:R536–44. doi: 10.1186/ar1706 7. Sokka T, Toloza S, Cutolo M, Kautiainen H, Makinen H, Gogus F, et al. Women, Men, and Rheumatoid Arthritis: Analyses of Disease Activity,
Disease Characteristics, and Treatments in the QUEST-RA Study. Arthritis
Res Ther (2009) 11(1):R7. doi: 10.1186/ar2591 17. Biró E, Nieuwland R, Tak PP, Pronk LM, Schaap MC, Sturk A, et al. Activated
Complement Components and Complement Activator Molecules on the
Surface of Cell-Derived Microparticles in Patients With Rheumatoid
Arthritis and Healthy Individuals. Ann Rheum Dis (2007) 66:1085–92. doi: 10.1136/ard.2006.061309 8. Smolen JS, Aletaha D, Barton A, Burmester GR, Emery P, Firestein GS, et al. Rheumatoid Arthritis. Nat Rev Dis Primers (2018) 4:18001. doi: 10.1038/nrdp.2018.1 9. FUNDING We demonstrate elevated levels of circulating EVs in patients
with established RA in relation to inflammatory burden and
coagulation activation. Larger studies are needed to confirm
these preliminary findings. The study was performed by grants provided by Region
Stockholm (ALF project), King Gustaf the V-80 years
foundation and the Swedish Rheumatism Association. The study was performed by grants provided by Region
Stockholm (ALF project), King Gustaf the V-80 years
foundation and the Swedish Rheumatism Association. Atherosclerosis in Rheumatoid Arthritis. Immunol Res (2018) 66:655–62. doi: 10.1007/s12026-018-9053-0 DISCUSSION Systemic inflammation in RA is accompanied by activation of
the vascular endothelium (44). Still, the levels of EVs expressing
E-selectin and endothelium-derived EVs were not significantly July 2021 | Volume 12 | Article 718845 Frontiers in Immunology | www.frontiersin.org 7 Stojanovic et al. Extracellular Vesicles in RA Patients ETHICS STATEMENT The studies involving human participants were reviewed and
approved by Ethics Committee of the Clinical Center
Kragujevac, Serbia. The patients/participants provided their
written informed consent to participate in this study. AUTHOR CONTRIBUTIONS The important limitation of our study is small number of
investigated subjects. However, the patients were well characterized
forthepresenceoftraditionalcardiovascularriskfactorsandongoing
medications and had moderate to high disease activity, thus enabling
an assessment in a real-life setting. AS and MV collected samples. AS, IP, and YZ performed the
experiments. AS and AA performed statistical analyses. AA and VJ
designed the study. AA, VJ, and MV supervised the manuscript. All
authors contributed to the article and approved the submitted version. DATA AVAILABILITY STATEMENT different in plasma from RA patients compared to HC. E-selectin
might only be transiently expressed on endothelial cells in
RA patients and therefore might be difficult to detect (34). In
a study by Viñuela–Berni et al., the administration of
immunosuppressive therapy (methotrexate, sulphasalazine, and
low-dose glucocorticoids) led to a significant reduction of the
plasma levels of CD62E+ EVs (39). Further, Hjeltnes et al. showed
that administration of methotrexate or a combination of
methotrexate and TNFa inhibitor decreased the serum level of
E-selectin (45), and the levels of endothelium-derived EVs levels
increased and then decreased after four months of anti-TNFa
therapy (46). The expression of endothelium-derived EVs in
comparison to PEVs was rather low and might therefore be
more sensitive to the ongoing immunosuppressive therapy in the
investigated group of patients. different in plasma from RA patients compared to HC. E-selectin
might only be transiently expressed on endothelial cells in
RA patients and therefore might be difficult to detect (34). In
a study by Viñuela–Berni et al., the administration of
immunosuppressive therapy (methotrexate, sulphasalazine, and
low-dose glucocorticoids) led to a significant reduction of the
plasma levels of CD62E+ EVs (39). Further, Hjeltnes et al. showed
that administration of methotrexate or a combination of
methotrexate and TNFa inhibitor decreased the serum level of
E-selectin (45), and the levels of endothelium-derived EVs levels
increased and then decreased after four months of anti-TNFa
therapy (46). The expression of endothelium-derived EVs in
comparison to PEVs was rather low and might therefore be
more sensitive to the ongoing immunosuppressive therapy in the
investigated group of patients. The raw data supporting the conclusions of this article will be
made available by the authors, without undue reservation. REFERENCES Boyer JF, Gourraud PA, Cantagrel A, Davignon JL, Constantin A. Traditional
Cardiovascular Risk Factors in Rheumatoid Arthritis: A Meta-Analysis. Joint
Bone Spine (2011) 78:179–83. doi: 10.1016/j.jbspin.2010.07.016 18. van Eijk IC, Tushuizen ME, Sturk A, Dijkmans BA, Boers M, Voskuyl AE, et al. Circulating Microparticles Remain Associated With Complement Activation
Despite Intensive Anti-Inflammatory Therapy in Early Rheumatoid Arthritis. Ann Rheum Dis (2010) 69:1378–82. doi: 10.1136/ard.2009.118372 10. Pisetsky DS, Ullal AJ, Gauley J, Ning TC. Microparticles as Mediators and
Biomarkers of Rheumatic Disease. Rheumatol (Oxford) (2012) 51:1737–46. doi: 10.1093/rheumatology/kes028 11. Barbati C, Vomero M, Colasanti T, Ceccarelli F, Marcosano M, Miranda F,
et al. Microparticles and Autophagy: A New Frontier in the Understanding of 19. Rodrı́guez-Carrio J, Alperi-López M, López P, Alonso-Castro S, Carro-
Esteban SR, Ballina-Garcı́a FJ, et al. Altered Profile of Circulating July 2021 | Volume 12 | Article 718845 Frontiers in Immunology | www.frontiersin.org 8 Extracellular Vesicles in RA Patients Stojanovic et al. Microparticles in Rheumatoid Arthritis Patients. Clin Sci (Lond) (2015)
128:437–48. doi: 10.1042/CS20140675 36. Rinder HM, Bonan JL, Rinder CS, Ault KA, Smith BR. Activated and
Unactivated Platelet Adhesion to Monocytes and Neutrophils. Blood (1991)
78:1760–9. doi: 10.1182/blood.V78.7.1760.bloodjournal7871760 20. Vranic A, Pruner I, Veselinovic M, Soutari N, Petkovic A, Jakovljevic V, et al. Assessment of Hemostatic Disturbances in Women With Established
Rheumatoid Arthritis. Clin Rheumatol (2019) 38:3005–14. doi: 10.1007/
s10067-019-04629-8 37. Villar-Vesga J, Grajales C, Burbano C, Vanegas-Garcı́a A, Muñoz-Vahos CH,
Vásquez G, et al. Platelet-Derived Microparticles Generated In Vitro Resemble
Circulating Vesicles of Patients With Rheumatoid Arthritis and Activate
Monocytes. Cell Immunol (2019) 336:1–11. doi: 10.1016/j.cellimm.2018.12.002 21. Aletaha D, Neogi T, Silman AJ, Funovits J, Felson DT, Bingham CO3rd, et al. 2010 Rheumatoid Arthritis Classification Criteria: An American College of
Rheumatology/European League Against Rheumatism Collaborative
Initiative. Ann Rheum Dis (2010) 69:1580–8. doi: 10.1136/ard.2010.138461 38. Silverstein RL, Nachman RL. Thrombospondin Binds to Monocytes-
Macrophages and Mediates Platelet-Monocyte Adhesion. J Clin Invest
(1987) 79:867–74. doi: 10.1172/JCI112896 39. Viñuela-Berni V, Donı́z-Padilla L, Figueroa-Vega N, Portillo-Salazar H, Abud-
Mendoza C, Baranda L, et al. Proportions of Several Types of Plasma and Urine
Microparticles Are Increased in Patients With Rheumatoid Arthritis With
Active Disease. Clin Exp Immunol (2015) 180:442–51. doi: 10.1111/cei.12598 22. Prevoo ML, van ‘t Hof MA, Kuper HH, van Leeuwen MA, van de Putte LB,
van Riel PL. Modified Disease Activity Scores That Include Twenty-Eight-
Joint Counts. REFERENCES Development and Validation in a Prospective Longitudinal
Study of Patients With Rheumatoid Arthritis. Arthritis Rheum (1995) 38:44–8. doi: 10.1002/art.1780380107 40. Cloutier N, Tan S, Boudreau LH, Cramb C, Subbaiah R, Lahey L, et al. The
Exposure of Autoantigens by Microparticles Underlies the Formation of
Potent Inflammatory Components: The Microparticle-Associated Immune
Complexes. EMBO Mol Med (2013) 5:235–49. doi: 10.1002/emmm.201201846 23. Kirwan JR, Reeback JS. Stanford Health Assessment Questionnaire Modified
to Assess Disability in British Patients With Rheumatoid Arthritis. Br J
Rheumatol (1986) 25:206–9. doi: 10.1093/rheumatology/25.2.206 41. György B, Szabó TG, Turiák L, Wright M, Herczeg P, Lédeczi Z, et al. Improved Flow Cytometric Assessment Reveals Distinct Microvesicle (Cell-
Derived Microparticle) Signatures in Joint Diseases. PloS One (2012) 7:e49726. doi: 10.1371/journal.pone.0049726 24. Zong Y, Pruner I, Antovic A, Taxiarchis A, Vila ZP, Soutari N, et al. Phosphatidylserine Positive Microparticles Improve Hemostasis in in-Vitro
Hemophilia A Plasma Models. Sci Rep (2020) 10(1):7871. doi: 10.1038/
s41598-020-64686-x 25. He S, Antovic A, Blombäck M. A Simple and Rapid Laboratory Method for
Determination of Haemostasis Potential in Plasma. II. Modifications for Use
in Routine Laboratories and Research Work. Thromb Res (2001) 103:355–61. doi: 10.1016/s0049-3848(01)00332-2 42. Palmer DG, Hogg N, Revell PA. Lymphocytes, Polymorphonuclear
Leukocytes, Macrophages and Platelets in Synovium Involved by
Rheumatoid Arthritis. A Study With Monoclonal Antibodies. Pathology
(1986) 18:431–7. doi: 10.3109/00313028609087564 26. Carter AM, Cymbalista CM, Spector TD, Grant PJ. Euroclot Investigators. Heritability of Clot Formation, Morphology, and Lysis: The EuroCLOT Study. Arterioscler Thromb Vasc Biol (2007) 27:2783–9. doi: 10.1161/ATVBAHA. 107.153221 43. Headland SE, Jones HR, Norling LV, Kim A, Souza PR, Corsiero E, et al. Neutrophil-Derived Microvesicles Enter Cartilage and Protect the Joint in
Inflammatory Arthritis. Sci Transl Med (2015) 7:315ra190. doi: 10.1126/
scitranslmed.aac5608 27. Lacroix R, Dubois C, Leroyer AS, Sabatier F, Dignat-George F. Revisited Role
of Microparticles in Arterial and Venous Thrombosis. J Thromb Haemost
(2013) 11(Suppl 1):24–35. doi: 10.1111/jth.12268 44. Kuuliala A, Eberhardt K, Takala A, Kautiainen H, Repo H, Leirisalo-Repo M. Circulating Soluble E-selectin in Early Rheumatoid Arthritis: A Prospective
Five Year Study. Ann Rheum Dis (2002) 61:242–6. doi: 10.1136/ard.61.3.242 28. Burnier L, Fontana P, Kwak BR, Angelillo-Scherrer A. Cell-Derived
Microparticles in Haemostasis and Vascular Medicine. Thromb Haemost
(2009) 101:439–51. doi: 10.1160/TH08-08-0521 45. Hjeltnes G, Hollan I, Førre O, Wiik A, Lyberg T, Mikkelsen K, et al. Serum
Levels of Lipoprotein(a) and E-selectin are Reduced in Rheumatoid Arthritis
Patients Treated With Methotrexate or Methotrexate in Combination With
TNF-a-Inhibitor. REFERENCES Clin Exp Rheumatol (2013) 31(3):415–21. 29. Sellam J, Proulle V, Jüngel A, Ittah M, Miceli Richard C, Gottenberg JE,
et al. Increased Levels of Circulating Microparticles in Primary Sjögren’s
Syndrome, Systemic Lupus Erythematosus and Rheumatoid Arthritis and
Relation With Disease Activity. Arthritis Res Ther (2009) 11(5):R156. doi: 10.1186/ar2833 46. Barbati C, Vomero M, Colasanti T, Diociaiuti M, Ceccarelli F, Ferrigno S, et al. Tnfa Expressed on the Surface of Microparticles Modulates Endothelial Cell
Fate in Rheumatoid Arthritis. Arthritis Res Ther (2018) 20:273. doi: 10.1186/
s13075-018-1768-8 30. Horstman LL, Jy W, Jimenez JJ, Bidot C, Ahn YS. New Horizons in the
Analysis of Circulating Cell-Derived Microparticles. Keio J Med (2004)
53:210–30. doi: 10.2302/kjm.53.210 Conflict of Interest: The authors declare that the research was conducted in the
absence of any commercial or financial relationships that could be construed as a
potential conflict of interest. 31. Šibı́ková M, Živný J, Janota J. Cell Membrane-Derived Microvesicles in
Systemic Inflammatory Response. Folia Biol (Praha) (2018) 64:113–24. Publisher’s Note: All claims expressed in this article are solely those of the authors
and do not necessarily represent those of their affiliated organizations, or those of
the publisher, the editors and the reviewers. Any product that may be evaluated in
this article, or claim that may be made by its manufacturer, is not guaranteed or
endorsed by the publisher. 32. Boilard E, Blanco P, Nigrovic PA. Platelets: Active Players in the Pathogenesis
of Arthritis and SLE. Nat Rev Rheumatol (2012) 8:534–42. doi: 10.1038/
nrrheum.2012.118 33. Xue LJ, Cui BB, Li X, Huang QR, Liu Y, Lin H. Association of Elevated Platelet
Microparticles With Disease Activity in Rheumatoid Arthritis. Sichuan Da
Xue Xue Bao Yi Xue Ban (2017) 48:405–9. Copyright © 2021 Stojanovic, Veselinovic, Zong, Jakovljevic, Pruner and Antovic. This
is an open-access article distributed under the terms of the Creative Commons
Attribution License (CC BY). The use, distribution or reproduction in other forums is
permitted, provided the original author(s) and the copyright owner(s) are credited and
that the original publication in this journal is cited, in accordance with accepted
academic practice. No use, distribution or reproduction is permitted which does not
comply with these terms. 34. Pamuk GE, Vural O, Turgut B, Demir M, Pamuk ON, Cakir N. Increased
Platelet Activation Markers in Rheumatoid Arthritis: Are They Related With
Subclinical Atherosclerosis? Platelets (2008) 19:146–54. doi: 10.1080/
09537100701210057 35. July 2021 | Volume 12 | Article 718845 REFERENCES Zubairova LD, Nabiullina RM, Nagaswami C, Zuev YF, Mustafin IG, Litvinov
RI, et al. Circulating Microparticles Alter Formation, Structure, and Properties
of Fibrin Clots. Sci Rep (2015) 5:17611. doi: 10.1038/srep17611 July 2021 | Volume 12 | Article 718845 Frontiers in Immunology | www.frontiersin.org 9
|
https://openalex.org/W3096301071
|
https://press.nordicopenaccess.no/index.php/noasp/catalog/download/111/539/4074
|
Norwegian
| null |
På tvers eller på langs? Setesdølane sin kontakt med verda ikring seg
| null | 2,020
|
cc-by
| 73,304
|
Grenseløst Agder
Det som skilte og det som bandt Berit Eide Johnsen og Kristoffer Vadum (red.) © 2020 Finn Holmer-Hoven, Dag Hundstad, Leonhard Jansen, Berit Eide Johnsen,
Nils M. Justvik, Jon P. Knudsen, May-Linda Magnussen, Bjørg Seland og Roger Tronstad Dette verket omfattes av bestemmelsene i Lov om opphavsretten til åndsverk m.v. av 1961. Verket utgis Open Access under betingelsene i Creative Commons-lisensen
CC-BY-NC-ND 4.0. Denne lisensen lar andre kopiere, distribuere og spre verket i hvilket
som helst medium eller format, under forutsetning av at det oppgis korrekt kreditering
og lenke til lisens. Dette kan gjøres på enhver rimelig måte, men uten at det kan forstås
slik at lisensgiver bifaller deg eller din bruk av verket. Materialet kan ikke benyttes til
kommersielle formål. Dersom du remixer, bearbeider eller bygger på materialet, kan du
ikke distribuere det endrede materialet. Lisensvilkår: https://creativecommons.org/licenses/by-nc-nd/4.0/deed.no ISBN trykt bok: 978-82-02-70293-9
ISBN PDF: 978-82-02-69682-5
ISBN EPUB: 978-82-02-70295-3
ISBN HTML: 978-82-02-70294-6
ISBN XML: 978-82-02-70296-0
DOI: https://doi.org/10.23865/noasp.111 Innhold Innledning .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
kapittel 1
Regional representasjon i storting og regjering. Hvor viktig er det? .. . . . . . . . . . . 13
Jon P. Knudsen
kapittel 2
Kristiansands rolle som regionalt styringssentrum i perioden 1641–1919 .. . . 30
Roger Tronstad
kapittel 3
På tvers eller på langs? Setesdølane sin kontakt med verda ikring seg .. . . . . . . 55
Leonhard Jansen
kapittel 4
Hva var det med Lillesand? Argumenter for valg og vraking av stortingsrepresentanter 1862–1931 . . . . . . 75
Berit Eide Johnsen
kapittel 5
Frivillige organisasjoner og regionbygging. Et eksempel fra Agder .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Dag Hundstad
kapittel 6
«Sørlandsmesterskapet». Idrett og idrettsutvikling på Agder før 1970 .. . . . . . 124
Nils M. Justvik
kapittel 7
Kjønnede hverdagsliv og likestillingsutfordringer på Agder. Regionale særtrekk og variasjoner i landsdelen .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
May-Linda Magnussen
kapittel 8
Konservative holdninger til likestilling på Sørlandet:
noen kulturhistoriske aspekter .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Forord Agderseminaret 2019 hadde tittelen Grenseløst Agder. Det som skilte og
det som bandt. Gjennom denne boka presenteres et flertall av foredragene
fra dette seminaret i artikkelform. Seminaret ble arrangert på KUBEN
Aust-Agder museum og arkiv i Arendal 17.–18. oktober 2019. Agderseminaret viderefører en lang tradisjon for seminarer om his-
toriske emner. Årlige sommerseminarer i historie ble arrangert fra 1976
og fram til 1999. Fra 2007 har rådet for Forskernettverk Agder holdt tra-
disjonen ved like med et seminar lagt til høsten. Forskernettverk Agder
ble etablert året før som et tiltak for å fremme forskning om og formid-
ling av Agders historie, og sette den inn i et videre perspektiv. Nettverket
omfatter samtlige av landsdelens institusjoner med historikere i staben,
samt Historisk forening Agder (HIFO Agder). Inntil 2015 ble seminarene
som regel fulgt av bokutgivelser. Etter den tid har utgivelsene skjedd som
Open Access-publikasjoner. Åtte av kapitlene i denne antologien er bearbeidede versjoner av fore-
drag som ble presentert på Agderseminaret 2019. Disse er supplert med
ytterligere ett bidrag, Bjørg Selands kapittel om konservative holdnin-
ger til likestilling på Sørlandet. De ni kapitlene favner bredt: Fra historie
til statsvitenskap og sosiologi, og fra oversiktsarbeider til mer spesifikke
undersøkelser. Tanken er at de skal gi grunnlag for diskusjon mellom
forskere med ulik faglig bakgrunn, samtidig som de skal ha interesse for
det allmenne publikum. Det overordnede målet er å bidra til en dypere
forståelse av landsdelens sosiale og kulturelle utvikling ved å fokusere på
sentrale temaer og sette disse inn i en større sammenheng. De seks historikerne som utgjør rådet for Forskernettverk Agder, har
fungert som redaksjonskomité: Gunhild Aaby, formidlingsleder ved
Vest-Agder-museet, Thomas Olsen, arkivar ved Statsarkivet i Kristian
sand / Arkivverket, Trond Bjerkås, førsteamanuensis ved Universitetet i
Agder, Leonhard Jansen, konservator ved Setesdalsmuseet / Aust-Agder
museum og arkiv, Kristoffer Vadum, forskningsleder ved Aust-Agder 5 forord museum og arkiv og Berit Eide Johnsen, professor ved Universitetet i
Agder. De to sistnevnte er også bokens redaktører. museum og arkiv og Berit Eide Johnsen, professor ved Universitetet i
Agder. De to sistnevnte er også bokens redaktører. Berit Eide Johnsen
Kristoffer Vadum
Kristiansand, oktober 2020 Berit Eide Johnsen
Kristoffer Vadum
Kristiansand, oktober 2020 6 Innhold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
Bjørg Seland innhold kapittel 9
«East is East and West is West, and never the twain shall meet.»
Et skråblikk på fylkessammenslåingen .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
Finn Holmer-Hoven
Bidragsytere .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202 196 . 202 8 8 Innledning Den 1. januar 2020 ble Aust-Agder og Vest-Agder slått sammen til ett
fylke, Agder. Det skjedde etter en lang prosess full av gode argumenter,
men ikke minst protester og motforestillinger. Etter manges mening var
det nå på tide å se framover. Men her spør vi i tillegg: Hvorfor ikke også
se oss tilbake? I denne antologien kaster ni historikere og samfunnsforskere et his-
torisk blikk på landsdelen vår, samtidig som de også har et nåtids- og
framtidsperspektiv. Bidragene favner vidt. I ett av dem drøftes det om
regionreformen vil styrke Agder som politisk kraft, og i et annet utforskes
regionen i administrativ og samfunnsgeografisk retning. Andre temaer
er stortingsvalg og politisk representasjon, organisasjoner og institusjo-
ner som både har hatt ett fylke og begge som geografisk ramme, kom-
munikasjonslinjer innad i regionen og landsdelen i et kjønnsperspektiv – både i dag og med vekt på historiske forklaringer. – både i dag og med vekt på historiske forklaringer. I det første kapitlet er samfunnsgeograf Jon P. Knudsens tema regional
representasjon i storting og regjering. Er det slutt på den tiden da politisk
representasjon er lik politisk makt? Og i så tilfelle; hvor ligger den egent-
lige makten? I veien fram til en konklusjon redegjør han blant annet for
partioppslutningen på Agder, presenterer sentrale agderpolitikere, drøfter
regional politikkutvikling og ser på hvordan regionen har vært represen-
tert på sentralt nivå. Et tema er også den nasjonale politikkens betydning
for Agder. Strukturelle forhold som urbanisering (Agderbyen), sentralise-
ring samt kommune- og fylkesstruktur trekkes også inn i analysen, som
bygger på så vel egne erfaringer som etablert samfunnsfaglig forskning. I neste kapittel undersøker historiker Roger Tronstad Kristiansands
rolle som regionalt styringssentrum i perioden 1641–1919. Gjennom disse
århundrene var Agder del av en større administrativ region som inklu-
derte både Rogaland og Telemark, der Kristiansand hadde rollen som
hovedsete for stiftamtmann og biskop. Vår tids regionreform er dermed
ikke uten historiske forløpere. Et sentralt tema i kapitlet er samspillet mel-
lom geistlige og verdslige øvrighetspersoner i forvaltningen av regionen 9 innledning og det store antallet stiftsomfattende organer som i praksis bandt områ-
det sammen. Avslutningsvis drøftes periodens kontinuitet opp mot de
endringene som trådte i kraft etter 1919. I det tredje kapitlet tar historiker Leonhard Jansen for seg veiene
som regionale forbindelseslinjer på Agder, med vekt på den betydning
de har hatt for setesdølenes kontakt med omverdenen. Innledning Den vanskelige
topografien i Setesdal innebar ofte at heia var mer farbar enn selve dalen. Likevel har disse fysiske hindringene kun vært en av mange faktorer som
har hatt betydning for setesdølenes veivalg. Undersøkelsen viser hvordan
strukturelle endringer i næringsgrunnlag, administrativ organisering og
infrastruktur drev setesdølene i ulike retninger til ulike tider, men også
hvordan veibygging i nyere tid har ført til en stadig sterkere kanalisering
av trafikken nedover dalføret, mot Kristiansand. I det fjerde kapitlet er historiker Berit Eide Johnsens tema argumen-
ter for valg og vraking av stortingsrepresentanter. Rammen for denne
næranalysen er at ingen politikere fra nåværende Lillesand kommune
(tidligere bykommunen Lillesand og landkommunene Vestre Moland og
Høvåg) har oppnådd fast plass på Stortinget de siste hundre årene. I peri-
oden 1862–1931 kom derimot hele fire stortingspolitikere derfra. Johnsen
går inn på bakgrunnen for at de ble valgt og gjenvalgt, hvilke standpunk-
ter de inntok og hvilke interesser de representerte. Videre redegjør hun
for valgordningen, som endret seg i løpet av denne perioden, og vurderer
hvordan den kan ha virket inn. Dessuten presenteres de viktigste riks
politiske sakene som vakte engasjement lokalt, og hvordan de kan ha vir-
ket inn på valgene. Historikeren Dag Hundstads bidrag er en analyse av frivillige organi-
sasjoner og regionbygging på Agder. Med utgangspunktet i de teoretiske
begrepene identitetsregion og referanseregion kartlegger han i hvilken
grad landsdelen har fungert som et relevant og hensiktsmessig territorielt
rammeverk for frivillig samhandling, og har vært uttrykk for regional
tilknytning og identifikasjon. Dette dokumenteres kvalitativt med Agder
Historielag som eksempel. I en kvantitativ undersøkelse trekkes også
fylkesoverskridende kretser i hele landet inn. Analysen gir mange svar,
men Hundstad konkluderer med at den også kan være utgangspunkt
for å stille nye spørsmål når det gjelder forholdet mellom territorium og 10 innledning identitet, blant annet hvilke faktorer som avgjorde valg av fylkesvis eller
fylkesoverskridende organisering. Historikeren Nils M. Justvik tar deretter for seg idretten og idretts-
historien i et regionalt perspektiv. Aust-Agder hadde før 1970 en sterkere
resultatliste enn nabofylket i vest. De sentrale spørsmålene er for det
første hvordan enkelte idrettsutøvere på Agder kunne gjøre det såpass
bra til tross for beskjedne rammebetingelser, og for det andre om for-
skjeller i idrettsprestasjoner mellom de to fylkene skyldtes strukturelle
ulikheter mellom øst og vest. Kapitlet viser innledningsvis hvordan den
organiserte idretten i Norge hadde en pionerfase i arendalsområdet. Innledning Selv
om Kristiansand etter hvert ble et senter for idrett på Sørlandet og en
driver for mange utøvere, forble bygdene likevel en viktig leverandør av
idrettsprestasjoner. Årsaken til dette var at mye av kraften i den regionale
idrettsbevegelsen lå i små, tette miljøer preget av utstrakt allsidighet. En
annen faktor som utforskes, er hvorvidt den pietistiske vekkelsesbevegel-
sen fra 1870-tallet slo sterkere inn i vestlige deler av Agder når det gjaldt
motstand mot idretten. I kapittel sju konstaterer samfunnsforskeren May-Linda Magnussen
at Agder over flere år er blitt rangert som den minst likestilte delen av
Norge – et likestillingsmessig annerledesland. Hun presenterer omfat-
tende statistikk fra Statistisk sentralbyrå (SSB), og drøfter på grunnlag
av den hvordan landsdelen skiller seg fra andre deler av landet når det
gjelder likestillingsutfordringer. Et fokus er også variasjoner innad i
landsdelen. I analysen trekker hun inn ulike forskningsbidrag så vel som
kvalitativt materiale (intervjuer) når hun reflekterer rundt mulige årsaker
til at hverdagslivene til folk på Agder ser ut til å være mer kjønnede enn
ellers i landet. Hennes konklusjoner knyttes til holdninger, forventninger
og praksis hos både kvinner og menn. Avslutningsvis konstaterer hun
at regionale særtrekk og interne variasjoner i landsdelen har mye med
økonomi, næringsstruktur og arbeidsmarkeder å gjøre, men at de også
dreier seg om kulturforskjeller som ikke uttømmende kan forklares med
klasseforskjeller. Historiske forklaringer som religiøst liv må også trekkes
inn, og med dette viser hun direkte til neste kapittel. Historikeren Bjørg Selands bidrag dreier seg om kulturhistoriske
aspekter ved synet på kjønnsmessig likestilling. Hun konstaterer at 11 innledning sørlendingene synes å stå for en konservatisme som vanskelig kan for-
klares uten å trekke inn den religiøse kulturarven. Hennes hovedfokus
er kjønnsrollemønstre på 1800- og 1900-tallet knyttet til den kristelige
lekmannsbevegelsen, nærmere bestemt bedehuskulturen. Den innbefat-
tet så vel den tradisjonelle misjonskvinnerollen (knyttet til kvinne- eller
håndarbeidsforeninger) som mer myndige religiøse kvinneroller (for-
melle og uformelle eliteposisjoner). Hun viser også til visse topografiske
og næringsstrukturelle forhold som kan bidra til å forklare at konser-
vative holdninger til likestilling har holdt stand. Her peker hun på den
tette kulturkontakten mellom Sørlandet og USA, som la grunnlag for at
innflytelsen fra angloamerikansk vekkelseskristendom ble særlig sterk
i denne landsdelen. Underveis i analysen problematiserer hun for øvrig
forestillingen om Agder som «annerledeslandet». Innledning I den forbindelse viser
hun til et mer omfattende sør- og vestlandsk bibelbelte, der Rogaland
var kjerneområde og spredningssenter for 1800- og 1900-tallets folkelige
pietisme. At Rogaland skårer høyere enn Agder på dagens statistikk for
likestilling, antar hun kan ha sammenheng med en ulik utvikling innen
økonomi og næringsliv i nyere tid. Avslutningsvis kaster tidligere redaktør i Fædrelandsvennen, Finn
Holmer-Hoven, et skråblikk på den langvarige – og til tider intense –
kampen mellom Aust-Agder og Vest-Agder. Han siterer Rudyard Kipling,
som i 1889 skrev i diktet «The Ballad of East and West»: «East is East and
West is West, and never the twain shall meet». Er det dette diktet som
best vil beskrive det fremtidige, sammenslåtte Agder? Kanskje. Eller er
det er håp om forsoning? 12 12 kapittel 1 Sitering av dette kapitlet: Knudsen, J.P. (2020). Regional representasjon i storting og regjering. Hvor
viktig er det? I Johnsen, B.E. og Vadum, K. (red.), Grenseløst Agder. Det som skilte og det som bandt
(s. 13–29). Oslo: Cappelen Damm Akademisk. https://doi.org/10.23865/noasp.111
Lisens: CC BY-NC-ND. Regional representasjon i storting
og regjering. Hvor viktig er det? Jon P. Knudsen For en tid siden fikk jeg en epost fra en representant for det vi med Jürgen
Habermas (1962/2002) må kunne kalle den borgerlige offentligheten på
Agder, Knut O. Mygland. Han var indignert over at det ikke var interesse
ved vårt eget universitet for regionens rikspolitiske betydning: Min påstand er at Indre Agder og dalstroka innafor blir litt neglisjert på UiA. Det er for lite søkelys på det politiske tyngdepunkt som var i Eiken/Fjotland på
1910- og 1920-tallet. En av pådriverne for kvinnelig stemmerett, stortingsmann
Eftestøl, kom fra Fjotland. Den markante stortingspolitikeren og venstreman-
nen Gunnuf Eiesland var herfra. Likedan stortingspresident Bryggesaa. Men
dette politiske miljøet er nesten glemt, selv om disse i en periode var viktige
rikspolitikere. (Mygland, personlig kommunikasjon, 22. august 2019) Min umiddelbare reaksjon var at det nok ikke bare er Indre (Vest-)Agder
som er glemt av Universitet i Agder. Og det er heller ikke bare ved UiA
det glemmes. Det er vel heller slik at studier av stortingsrepresentasjon
nærmest har gått av moten som forskningsfelt. I tidligere tider var dette et
viktig tema. Utover i etterkrigstiden kom meningsmålingene, som brakte
folk til å tro på desimaler hinsides all statistisk forsiktighet. I valgforsk
ningens storhetstid var i tillegg troen på at politisk representasjon var lik
politisk makt, svært så utbredt. Men så kom Stein Rokkan (1966) med et nytt budskap: Stemmer teller,
men ressurser avgjør. Gradvis ble interessen for den synlige representasjon 13 kapittel 1 i regjering og storting avløst av en søken etter hvor den egentlige mak-
ten fantes. Både akademisk og politisk ble dagsorden dermed en annen. Tydeligst kom dette til uttrykk gjennom den brede maktutredningen som
ble igangsatt i 1972 og rapportert i 1983 (St. meld. nr. 44 (1982–83)). Nå var
det interesseorganisasjonene, de korporative kanalene og maktspillet i
parlamentarismens bakrom som skulle fram i lyset. Der fikk forskningen
annet å stelle med. Stortingsrepresentasjonen ble overlatt til kommer
sielle meningsmålere, memoarlitteraturen og lokale delegasjoner på tur
til Oslo med en sak. Forskningsfokus hadde beveget seg fra den nume-
riske til den korporative kanal. Ottar Hellevik (1969) hadde rett nok for-
talt oss at Stortinget representerte en sosial elite, men det var likevel en
elite som selv ofte følte mer avmakt enn makt. Det skulle heller ikke mye
til for å få elitestemplet hos Hellevik. Det holdt med examen artium og
en håndfull verv. Regional representasjon i storting
og regjering. Hvor viktig er det? Og typisk nok, da sluttrapporten fra maktutredningen
ble debattert i Stortinget, visste de angivelige makthavere knapt hva de
skulle bruke den til. Likevel, bildet over må nyanseres. Selv om forskningsinteressen har
flyttet seg, er det ikke slik at den nasjonale representasjonen er uviktig. Det umiddelbare inntrykket er også at representasjon i regjering er noe
som vies mer oppmerksomhet enn representasjon i storting. Og går vi
til Stortingets sammensetning og arbeidsmåter, er det opplagt interes-
sant hvilke fagkomiteer representantene havner i og hvilke posisjoner de
får internt i partigruppene. Av særlig interesse er de posisjonene der den
parlamentariske arenaen møter andre maktsfærer. Et borgerlig Agder En observasjon må legges til for landsdelens representasjon i regjering. For Agders del har den som regel vært sterkere i borgerlige enn i arbeider-
partiledede regjeringer. Dette følger rett og slett av landsdelens politiske
geografi. Agder stemmer mindre rødt enn landsgjennomsnittet, selv om
det er store interne forskjeller. Grovt sett kan vi si at Agder blir rødere jo
lengre øst og innover i landet vi kommer og blåere – og gulere – desto
lengre vest og ut mot kysten vi befinner oss (Aardal, 2011). 14 regional representasjon i storting og regjering. hvor viktig er det? Skal vi reformulere problemstillingen, kan vi kanskje si at hvordan vi
er representert i storting og regjering er viktigere enn at vi er det. Det er
forskjell på å sitte på avgjørende poster der makten utøves, og å få tildelt
et par statssekretærposter som avlat i et rikspolitisk spill. Jon Lilletun og
Ansgar Gabrielsens karrierer kan være eksempler på hvordan det arter
seg for dem som virkelig når inn til maktens midte. Jon Lilletun er kanskje den fremste politikeren Agder har fostret i nyere
tid. Han kom fra små kår på Vestlandet og bar med seg den klassiske
Venstre-ideologien slik den hadde vokst fram i samspill med motkultu-
rene: avhold, lekmannsrørsle og målsak. Lilletun personifiserte dem alle,
på sitt vennlige, spørrende og kulturåpne vis. Nils Kjær ville ikke ha fun-
net spor av Vestlandsfanden i ham. Lilletun søkte kompromisser. Før han
kom inn i rikspolitikken, hadde han gjort seg bemerket i utvekslingen
mellom kommunalt tiltaksarbeid og frivillig organisasjonsliv i Vennesla. Han var kraft og brobygger. På Stortinget ble det likeens. Han satt som fast representant for
Vest-Agder KrF fra 1989 til han døde i 2006. Også her ble han brobygge-
ren. To eksempler illustrerer dette godt. Han fikk fra første stund av god
kontakt med politikere fra andre partier. Han var i perioden 1989–1997
først medlem og senere leder av kirke-, undervisnings- (og forsknings-)
komiteen. Dette falt sammen med at Gudmund Hernes, Ap, var fagstats-
råd (1990–1995) og Randi Øverland fra Vest-Agder statssekretær i samme
departement. Hernes og Lilletun fant hverandre umiddelbart over blokk-
skillet. Lilletun hadde også en god tone med Arbeiderpartiets folk i sin
egen komité. Det er i ettertid ikke tvil om at denne kontakten var viktig
for å drive høgskolesamlingen på Agder – og senere universitetsprosjektet
– fram. Et borgerlig Agder Forholdet mellom mange av landsdelens akademikere og statsråd
Hernes var på samme tid anstrengt, etter at statsråden tidlig hadde satt
foten ned for å skape et femte universitet i Norge ved fusjon mellom de
daværende høgskolene i Kristiansand (ADH) og Stavanger (HSR) (Knud-
sen, 2019, s. 254–255). Da Kjell Magne Bondevik dannet sin første regjering etter valget i 1997,
ble Lilletun kirke-, utdannings- og forskningsminister. Jeg var da poli-
tisk redaktør i Fædrelandsvennen, og befant meg i Oslo da dette skjedde. Over en kopp kaffe i stortingsrestauranten ga Lilletun uttrykk for tvil om 15 kapittel 1 egne evner. Ville han makte oppgaven? Han besto så avgjort. Da Bonde
vik dannet sin andre regjering høsten 2001, bestående av KrF, Høyre og
Venstre, var den parlamentariske situasjonen vanskelig. Dermed fikk
Lilletun jobben med å lose regjeringens saker gjennom i Stortinget. Han
ble fellesparlamentarisk leder for regjeringspartiene. Midtbanespille-
ren Bondevik (Rimehaug, 1997) trengte Lilletuns samarbeidsevner og
kontaktnett for å lykkes. Bondevik behersket ikke denne delen av banen
alene. De kontrafaktiske spørsmålene har liten plass i samfunnsforsknin-
gen, men det er likevel ikke til å unngå at spørsmålet stilles: Hvordan ville
utfallet av striden om KrFs linjevalg i 2019 ha vært dersom Lilletun hadde
fått leve lenge nok til å ta del i den diskusjonen (Erstad, 2019)? Ansgar Gabrielsens vei til makt og innflytelse har noen av de samme
ingrediensene. Han hadde tidlig markert seg som omgjengelig og talent-
full ordfører (H) i Lindesnes før han havnet på Stortinget i 1993. Den
første perioden i rikspolitikken var han lite synlig, men etter valget i
1997 ble han valgt som innpisker for Høyres stortingsgruppe. I Bonde-
viks andre regjering ble han først næringsminister og deretter, fra 2004
av, helseminister. Som næringsminister høstet han internasjonal berøm-
melse for å ha drevet gjennom lovendringen som krevde 40 prosent
kvinnerepresentasjon i aksjeselskapenes styrer. Som helseminister var
han aktiv for å befeste reformen som fra 2002 av overførte sykehusene fra
fylkeskommunalt eierskap til statlige foretak. Etter at han gikk ut av riks
politikken i 2005 startet Gabrielsen eget firma, som dannet utgangspunkt
for videre engasjement i norsk helse- og sykehusvesen. Fra denne posisjo-
nen har han siden blant annet vært engasjert som pådriver for utviklin-
gen av Oslo Cancer Cluster og for etableringen av en ny helsebydel på Eg
i Kristiansand. Begge disse eksemplene illustrerer at rikspolitikken byr fram arenaer
for handling. Et borgerlig Agder Men samtidig viser det at det er egenskaper hos aktørene
– og koplinger mellom aktører på ulike arenaer – som bestemmer om
representasjonen skal omsettes i reell innflytelse. Slik forstått viser også
disse eksemplene hvordan ulike former for individuell og sosial kapital
inngår som byttemiddel for å skaffe innflytelse i politikken. Dette er et
felt som det er skrevet svært mye om, både innenfor generell samfunns
teori og mer spesifikt innenfor den type statsvitenskapelig litteratur 16 regional representasjon i storting og regjering. hvor viktig er det? som behandler slike temaer (Bourdieu, 1979/1995; Granovetter, 1973;
Putnam, 2001). Jeg vil hevde at det finnes flere historiske og nyere eksempler på slike
koplinger. En av arkitektene bak Bondepartiets reformistiske linje og for-
liket med Arbeiderpartiet på 1930-tallet var Gabriel Moseid, også han fra
Vennesla. Som Lilletun er han svært relevant for å forstå hvordan kom-
promisser blir til. Det klasseforliket som fant sted mellom bønder og
arbeidere midt i dette tiåret, var skjellsettende for norsk politikks videre
utvikling (Nielsen, 2001). Rikspolitisk var Moseid antakelig viktigere enn
Lilletun, men så virket han også i en helt annen tid. For den institusjonelle
utviklingen på Agder var kanskje Lilletun viktigere, særlig gjennom sitt
arbeid med universitetssaken. Flytter vi oss til den første etterkrigstiden,
finner vi Venstre-høvdingen Bent Røiseland, som gjerne omtales som den
beste statsministeren vi aldri fikk (Garvik, Vetland & Røiseland, 2003). Røiseland var også en samarbeidets mann, men da som talsmann for bor-
gerlig samling som et alternativ til det Rune Slagstad (1998, s. 191–364)
kom til å benevne Arbeiderpartistaten. Går vi helt fram til vår egen tid, ser vi igjen hvordan aktører fra Agder
blir sentrale i utformingen av rikspolitikken. KrF er i dag et mindre
parti enn på lenge, men partiet ble likevel, blant annet gjennom den
opprivende striden om linjevalget etter stortingsvalget i 2017, jokeren i
regjeringskabalen. Med ett var Kjell Ingolf Ropstad fra Evje og Horn-
nes partileder, mens den mangeårige Lyngdals-ordføreren Hans Fredrik
Grøvan ble gruppeleder i Stortinget. Som en kuriositet kan også nevnes
hvordan vestre Vest-Agder igjen ble synlig på Stortinget etter valget i
2013. Men nå ble tyngdepunktet flyttet fra Eiken og Fjotland til kysten
i det nye Lister. Ingunn Foss (H), Hans Fredrik Grøvan (KrF) og Odd
Omland (Ap) utgjorde en periode nærmest en egen Lister-benk. Et borgerlig Agder Det er allerede nevnt at Agders mest framtredende representanter har
vært borgerlige politikere, mens Arbeiderpartiets folkevalgte mer har fylt
de bakre rekkene. Noen navn bør likevel nevnes. I nyere tid er det bare
Grete Faremo som har profilert seg som Ap-statsråd fra landsdelen. Den
siste før henne var Jens Haugland, som satt i Einar Gerhardsens regje-
ringer fra 1955 til 1965. Begge kom fra de indre bygder, Faremo fra Setes-
dal og Haugland fra Bjelland i Marnardal. Faremo har aldri representert 17 kapittel 1 landsdelen som folkevalgt. Haugland hadde sentrale roller som justis- og
kommunalminister. Hans betydning for å drive gjennom vesentlige refor-
mer som 1960-årenes kommunereform og innføring av bygningsloven i
1965 er ennå lite utforsket. Sigurd Verdal bør også trekkes fram. Han satt
på Stortinget fra 1981 til 1993, og var i perioden 1985 til 1989 visepresident
i Lagtinget. Fra 1992 til 2000 var han leder av det nasjonale Omsetnings-
rådet for landbruket. Verdals regionale kongstanke var å gjøre Byremo
til et kraftsentrum for indre Vest-Agder, slik Evje var det i Setesdal. Han
lyktes for skolesatsingen, men ellers er det få spor av regional sentralise-
ring i denne delen av Agder. Lenger tilbake finner vi Nils Hjelmtveit fra Eydehavn som var kirke-
og undervisningsminister fra 1935 til 1945 og etter den tid fylkesmann i
Aust-Agder. Nevnes bør også østlendingen Lars Evensen, som var indus-
triminister i Gerhardsens regjering i perioden 1947 til 1953. Fra 1954 til
1966 var han fylkesmann i Vest-Agder, og han brukte da sine erfaringer
fra statsrådstiden til å kople utenlandske industriinteresser til de store
kraft- og industriprosjektene i vestre del av fylket. Nominasjon og rekruttering Ser vi på utvelgelsen av representanter, synes det også å være en markant
forskjell i måten dette gjøres på i Arbeiderpartiet og de ikke-sosialistiske
partiene. I Arbeiderpartiet har det vært tradisjon for at kandidatene stil-
ler seg til disposisjon, og at den partiet nominerer, blir renominert både
én og to ganger uten at det skjeles til rikspolitisk oppdrift. Hensynet til
balansen mellom kjønn, lokalgeografi og kopling til fagbevegelsen teller
mer enn individuelle egenskaper. Så ikke i Høyre, KrF og Fremskritts-
partiet. I Vest-Agder Høyre gikk Peter Gitmark hardt til verks for å slå ut
den sittende representanten, Anne Berit Andersen, før valget i 2005. Hans
Fredrik Grøvan kjørte like røft mot KrFs nestleder, Dagrun Eriksen, for
å erobre hennes plass som listetopp i samme fylke forut for valget i 2013. Og for den som observerte oppkjøringen til stortingsvalget i 1997, var det
langt fra noen idyll å spore mellom Fremskrittspartiets førstekandidat
i Vest-Agder, Vidar Kleppe fra Kristiansand, og andrekandidaten, Odd
Djøseland fra Farsund. 18 regional representasjon i storting og regjering. hvor viktig er det? Noen av disse konfliktene hadde ideologiske sider ved seg, som kam-
pen mellom Grøvan og Eriksen. I andre tilfeller dreide det seg mer om
personlig rivalisering. Under valgkampen høsten 1997 kom det en dag et
brev til Fædrelandsvennens redaksjon fra Odd Djøseland med et vold-
somt angrep på listekollega Kleppe. Djøseland ønsket brevet trykt som
innlegg på debattsidene underskrevet: «En som ønsker Kleppe-fri sone». Ønsket ble ikke etterkommet, men saken ble heller ikke forfulgt som
nyhetssak – den gang. I betydelig grad er disse seleksjonsprosessene utslag av nasjonale
partikulturer. I arbeiderbevegelsen stiller medlemmene seg til kollek-
tivets disposisjon, og oppgaven for en stortingsrepresentant er først og
fremst å stemme riktig, ikke å opptre individuelt og originalt. Aust-Agder
Arbeiderpartis mangeårige representant Osmund Faremo passet ikke
helt inn i denne formen, og kunne ofte opptre i fri dressur. Han ble blant
annet landskjent da han i 1974 foreslo å innføre offentlig produktkontroll
for politisk journalistikk. I andre partier vil toleransen for individuelle
ambisjoner være større. Grøvans kamp mot Eriksen kan i så måte gis
ideologisk dekning fra Linderot-salmen «Ingen vinner frem til den evige
ro som seg ei veldig fremtrenger» (Linderot, 1798/1985). Representasjonens strukturelle bakteppe Spør vi oss nærmere om hva den rikspolitiske representasjonen betyr i
en regional sammenheng, er det fristende å se mer systematisk på spørs-
målet om geografien i politikken. For igjen å trekke på Rokkan (1967) er
Norge som statsdannelse å betrakte som et kompromiss mellom regionale
interesser. I 1814 skulle dette landet, som siden det opphørte å eksistere
som egen stat i senmiddelalderen hadde mistet mye av sitt territorium
i både øst og vest, igjen skapes som politisk størrelse. Utgangspunktet
var dårlig. Landet hang ikke sammen kommunikasjonsmessig, og det var
snarere en samling regionalt atskilte økonomier i gjensidig utakt (Hodne,
1981; Sejersted, 2002) enn noe som liknet et hele. Nasjonsbyggingen kom
da også til å ta form av kamp mellom ulike interesser, regionalt som kul-
turelt. Så sent som på slutten av 1800-tallet diskuterte målrørsla om Norge
skulle forstås som befolket av to konkurrerende nasjoner (Hoel, 2009). 19 kapittel 1 I dette perspektivet kom behovet for å holde landet sammen til å bli
et overordnet politisk anliggende, og regional- og distriktspolitikk kom
utover på 1900-tallet til å utkrystallisere seg som nasjonal metapolitikk
(Knudsen, 2018, 2019). Det er først i nyere tid at dette politiske rasjonalet
har forvitret. Det er mange måter å forstå denne forvitringen på, og en av
dem er at den klassiske distriktspolitikken, slik den hadde oppstått i kjøl-
vannet etter kriseforliket i 1935 og blitt institusjonalisert i etterkrigstidens
politiske programmer og satsinger, hadde utspilt sin rolle (Rasmussen,
2003). Noen vil hevde at dette mer skyldtes den ideologiske snuoperasjo-
nen som inntraff på 1980-tallet, med deregulering og nyliberalisme. Fra
tidlig på 1990-tallet er det uansett mulig å spore et markant taktskifte,
der disse tankeretningene kom til å berede grunnen for en nedbygging
av regionalpolitikkens betydning i Norge (Teigen, 2012, 2019). Paradok-
salt nok fikk denne utviklingen et ekstra skyv fra en ny miljøbevissthet,
der byen gikk fra å være forkjetret til å bli omfavnet. Mens 1970-tallets
grønne bølge rullet mot distriktene, trakk den et par tiår senere til byen. Et mer konsentrert bosettingsmønster var med ett løsningen på en rekke
politiske utfordringer (Næss, Saglie & Halvorsen-Thorén, 2015). Dermed ble den regionalpolitiske agendaen i Norge også mer kompleks. Fra gjenoppbyggingen etter krigen hadde den norske regionalpolitikken
i mangt vært en distriktspolitikk, først for Nord-Norge og Namdalen og
deretter for utkantene i Sør-Norge (Teigen, 2019). Representasjonens strukturelle bakteppe Kritikerne av denne
politikken ønsket heller å utvikle dynamiske byregioner rundt store og
mellomstore byer landet rundt etter svensk mønster. En av de fremste
talsmennene for en slik politikk var professor i samfunnsgeografi ved
Universitetet i Oslo Tor Fr. Rasmussen (1969, 2003), som var oppvokst
i Flekkefjord. Dette var en politikk det ikke var støtte for i Stortinget
før Arne Rettedal (H) ble kommunal- og arbeidsminister i 1981. Han lot
bevisst etableringsloven, som skulle hindre for sterk byggeaktivitet i og
rundt store byer, sove. Dermed var en skanse brutt, og framover mot vår
egen tid ble det nærmest et politisk mål å skape slike dynamiske arbeids-
og boligmarkeder rundt regionale bysentra, men da som et nasjonalt svar
på den amerikanske økonomen Michael Porters (1990) tese om at den
globale økonomien var konstituert ved samhandlingen mellom spesiali-
serte regionale økonomier. I EU fikk den samme ideen gjensvar gjennom 20 regional representasjon i storting og regjering. hvor viktig er det? slagordet om å skape et regionenes Europa (Magone, 2003). Regionalt
konsentrerte bo- og arbeidsmarkeder ble nøkkelen til utvikling mange
steder i Norge som i Norden forøvrig (Castells & Himanen, 2003). Iro-
nisk nok var det utkantideologen, professoren og SV-politikeren Ottar
Brox (1984) som først beskrev fenomenet ved å analysere den tilsyne
latende konsolideringen av et tidligere truet bosettingsmønster i Troms,
en bekreftelse på at en ny type pendlingsatferd hadde endret bosettings-
betingelsene i distriktene. I det mer folkerike lavlandet på Østlandet lan-
serte Tor Selstad (1983) begrepet Mjøsbyen for vise hvordan bystrukturen
rundt Mjøsa kunne forstås som et samlet byfelt for vekst og utvikling. j
y
g
g
På Agder ble Agderbyen lansert som merkelapp for de samme proses-
sene langs linjen Mandal–Tvedestrand. Dette bykonseptet ble beskre-
vet og analysert gjennom et regionalt scenarioprosjekt bestilt av de to
fylkeskommunene og medfinansiert av Miljøverndepartementet og tre
av landsdelens banker (Knudsen, Jacobsen & Svendal, 1990). Dette var
et bybegrep som skapte vel så mye strid som begeistring. Agderbyen ble
i Agders indre bygder og flanker oppfattet som den endelige bekreftel-
sen på sentraliseringstrusselen, mens den i Kristiansand og Arendal ble
forstått som et forsøk på å nulle ut de nedarvede og egentlige bysentra-
enes identitet og rolle. Dette forsto Victor D. Representasjonens strukturelle bakteppe Norman (H), opprinnelig
fra Risør og senere en tid bosatt i Lillesand, godt da han som statsråd
i Bondeviks andre regjering med ansvar for utflytting av statsinstitu-
sjoner fra hovedstaden i 2003 pekte på Agderbyen som lokalisering for
Post- og teletilsynet (nå Nasjonal kommunikasjonsmyndighet, NKOM). Slik tvang dermed Norman Agder-politikerne til å ta i det unevnelige. Sjokkvirkningen var om mulig enda større da samferdselsstatsråd Torild
Skogsholm valgte Lillesand som lokalisering for tilsynet. Med det var
forestillingen om Agderbyens funksjonalitet nasjonalt bekreftet. En ny bypolitikk Men de regionale byfeltene skulle, som nevnt, snart møte motbør fra den
nye miljøbevegelsens konsentrerte byforståelse. Der de store byfeltene
fordret utstrakt pendling og byspredning, forkynte den nye ideologien
konsentrert bebyggelse og kompakte byer. Reisene skulle tas kollektivt, 21 kapittel 1 eller aller helst med sykkel eller til fots. Lillesands Tine Sundtoft (H) ble
klima- og miljøminister i Erna Solbergs regjering for perioden 2013–2015. Hennes store sak var å forplikte Norge på en klimapolitikk der Kristian
sand ble det fremste regionale utstillingsvinduet for denne politikkens
konsekvenser. Og i Kristiansand satt Sundtofts partifelle og nære venn
Harald Furre som ordfører. Han kom dermed i en vanskelig situasjon. På den ene siden skulle han iverksette en restriktiv utbyggingspolitikk,
stimulert via statlige belønningsmidler. På den annen side skulle han føre
en politikk som befestet Kristiansand som landsdelens dynamiske sen-
trum. Dermed kunne han risikere å bli straffet ved bortfall av de samme
midlene. Dette fordret – og fordrer – en nærmest umulig balansegang
mellom nasjonale politiske krav og lokale ønsker. Vi har altså to interessante eksempler på at statsråder fra Agder, Nor-
man og Sundtoft, har fattet beslutninger med store konsekvenser for
og korrektiver til politisk praksis i egen landsdel. Begge statsråder kom
også fra Høyre, et parti som ellers ikke utmerker seg ved rabulisme. De
to eksemplene kan også være instruktive ved at de illustrerer hver sin
generasjon av bypolitikk. Norman betjente byregionen og Sundtoft den
kompakte byen. Dermed ga de hvert sitt bidrag til det som i dag er blitt
en fornyelse av den historiske spenningen i norsk politikk, nemlig mot-
setningen mellom by og land, mellom sentrum og utkant, Stein Rokkans
(1967) beskrevne hovedspenning i det norske nasjonsbyggingsprosjek-
tet. For om geografien har forvitret i politikken (Knudsen, 2018; Teigen,
2012), kan den nå være i ferd med å komme voldsomt tilbake. Konflikten mellom de to byperspektivene, det regionforstørrende og det
kompakte, skulle også finne et annet nedslag i vår landsdel. Det skjedde da
kommunene Iveland og Evje og Hornnes for et drøyt tiår siden ønsket å
realisere to større boligfelt, ett i Iveland og ett på Moisund. Fylkesmannen
i Aust-Agder reiste innsigelse mot planene med den begrunnelsen at disse
feltene ville stimulere til økt pendling mot byene ved kysten, siden de lokale
arbeidsmarkedene i de to kommunene ville være for tynne til å absorbere
de nye innbyggerne som feltene ville rekruttere. En ny bypolitikk Fylkesmannen påpekte at
en slik utvikling ville være i strid med nasjonal klimapolitikk, som la opp til
kompakte byer og korte arbeidsreiser. Ordførerne i de to kommunene, Ole
Magne Omdal (Sp) og Bjørn Ropstad (KrF), parerte raskt med at nasjonal 22 regional representasjon i storting og regjering. hvor viktig er det? distrikts- og regionalpolitikk tok til orde for det motsatte, nemlig at det
var et mål å skape regionforstørring med utgangspunkt i sterke, regionale
arbeidsmarkeder for å stimulere bosetting i distriktene. Kjell Ingolf Ropstad
(KrF), sønn av ordføreren i Evje og Hornnes, var inne i sin første stortings
periode og tok saken opp gjennom et spørsmål til miljøvernministeren, Erik
Solheim (SV), som da også var statsråd for plansaker. Men før statsråden
rakk å skifte sol og vind mellom to nasjonale politikkområder på kollisjons-
kurs, ble saken forlikt hos Fylkesmannen ved at kommunene aksepterte å
redusere størrelsen på boligfeltene (Knudsen, 2018). Men dermed kokte også
en sak med stort prinsipielt og rikspolitisk potensial bort i kålen. Kommune- og regionreform Spørsmålet om hensiktsmessigheten med den norske kommune- og
fylkesstrukturen har vært reist flere ganger opp gjennom historien. Første del av 1960-tallet gikk med til å sanere antall kommuner i Norge i
tråd med Schei-komiteens innstilling (Stugu, 2015). Agder fikk da i grove
trekk den kommunestrukturen landsdelen inntil nylig har hatt, med
unntak av Arendal, som forble en innklemt bykommune inntil byen ble
slått sammen med fire nabokommuner i 1992. Den pågående kommune
reformen har i Agder bare gitt tre realiserte prosesser: sammenslåing
av Lyngdal og Audnedal, fusjon av Mandal, Lindesnes og Marnardal,
og endelig et amputert Stor-Kristiansand bestående av Kristiansand,
Søgne og Songdalen. Hele det gamle Aust-Agder forblir dermed, i likhet
med mye av landet ellers, uberørt av kommunereformen så langt. En av
pådriverne for denne reformen er mangeårig statsråd i ulike departemen-
ter Monica Mæland, oppvokst i Arendal. For statssekretær i Kommunal-
og moderniseringsdepartementet Aase-Marte Johansen Horrigmo (H,
2018–2020), opprinnelig fra Vennesla, og hennes etterfølgere våren 2020,
først Harald Furre, så Paal Pedersen fra Mandal, er dette resultatet også
lite tilfredsstillende. Men slik denne saken har utviklet seg, er den nær-
mest uten dynamikk, og i alle fall noe ingen rikspolitisk folkevalgt fra
landsdelen ser som vinnersak for seg og sitt parti. Med fylkesreformen har det forholdt seg noe annerledes. Mens Høyre
og Fremskrittspartiet prinsipielt har ønsket fylkeskommunen bort, 23 kapittel 1 måtte Erna Solbergs første regjering akseptere at mellompartiene KrF og
Venstre fikk gjennomslag for at den skulle bestå. Noe annet var det ikke
flertall for i Stortinget. Med regionreformen ble også mandatet for fylkes
kommunene styrket, samtidig som de ble redusert i antall fra 19 til 11. Sammenslåingen av Agder-fylkene hadde vært vurdert en rekke ganger
før, men nå ble den effektuert med virkning fra 1. januar 2020. Sett uten-
fra synes det som om to av fylkessammenslåingene gikk enklere enn de
andre, nemlig den i Agder og den i Trøndelag. Begge hadde karakter av
å være modne og samtidig tilpasset en regional struktur med betydelig
etablert samhandling rundt ett, definert byfelt, for Agders del Agderbyen. Rikspolitisk hadde dette nærmest hatt karakter av en ekspedisjonssak. Men likevel bør KrFs rolle trekkes fram, fordi partiet er det av mellom-
partiene som grundigst omtalte saken i eget program, og fordi egdene
i stortingsgruppa var særlig sentrale i behandlingen av saken. Kommune- og regionreform Torhild
Brandsdal fra Vennesla hadde regionreformen som sitt ansvarsområde,
og i hennes sykefravær fungerte Per Sverre Kvinlaug fra Kvinesdal som
vikar, mens Hans Fredrik Grøvan holdt i de overordnede prinsippene for
behandlingen av saken. Regional politikkutvikling Når en skal analysere Agders rikspolitiske gjennomslag, holder det ikke
bare å se på representasjon i storting og regjering. En må også se på
hvilke saker som reises regionalt, og som formuleres og løses på andre
måter enn gjennom de nasjonale, representative kanaler. Her er det flere
eksempler. Om vi tar utgangspunkt i dokumentet Felles mål for Agder
(Norman, Røed & Knudsen, 1994) og de sakene som ble løftet fram der,
er to av dem typisk slike. Det ene er prosessen med å få nye E18 mellom
Kristiansand og Grimstad bygget som en sammenhengende firefeltsvei
og gjennom offentlig-privat samarbeid (OPS). En viktig driver i dette var
en regional veiaksjon der tunge representanter for offentlige og private
interessenter tok på seg refleksvester, bar fakler og aksjonerte for snarlig
handling. Til og med agderbispen lot seg mobilisere. Ved siden av dette
var det et betydelig initiativ i den regionale veiforvaltningen for samme
sak. Resultat var at dette veiprosjektet kunne åpnes for trafikk i 2009. 24 regional representasjon i storting og regjering. hvor viktig er det? Den andre prosessen som bør trekkes fram, er det arbeidet som ble
drevet regionalt for å skaffe kapital til å realisere kompetanse- og kultur
satsinger ut over det som kunne skaffes via ordinær statlig finansiering. Dette skjedde ved at det regionalt ble etablert stiftelser gjennom salg av
kraftaksjer for slike formål. De tre viktigste av disse var Cultiva for kultur
satsinger i Kristiansand, Sørlandets kompetansefond for Vest-Agder og
Aust-Agder utviklings- og kompetansefond for Aust-Agder. Særlig for
kulturfeltet er det uomtvistelig at innsatsen fra Cultiva har bidratt vesentlig
til å realisere eller framskynde både kulturaktiviteter og tilhørende insti-
tusjoner i Kristiansand (Johnsen, Dragseth, Johannessen & Lysgård, 2011). Et siste poeng som skal tas med i denne sammenhengen, er et arbeid
som ble initiert fra kommuneledelsen i Kristiansand rett etter århundre-
skiftet med tanke på la storbyene i Norge overta for fylkeskommunene
som regionale utviklingsaktører i en ren tonivåforvaltning. Ordfører
Bjørg Wallevik (H) og rådmann Erling Valvik organiserte sammen
et nettverk med sine kolleger i Oslo, Bergen, Stavanger, Trondheim og
Tromsø for å fremme tanken. Det ble utarbeidet et eget notat for dette,
blant annet bygd på finske erfaringer med tonivåforvaltning (Røed,
Knudsen & Fosse, 2002). Prosessen vakte interesse hos daværende kom-
munalminister Erna Solberg, men som del av Bondeviks andre regjering
var hun bundet av denne regjeringens fredning av fylkeskommunen. Regional politikkutvikling Prosessen er også interessant fordi den er et eksempel på at Kristiansand
tok rikspolitisk lederskap på et viktig saksfelt, storbypolitikken. Notatet
ble også presentert for Stortingets kommunalkomité med samme resul-
tat: interessert lunkenhet. Med den senere regionreformen under effek-
tuering er tonivåmodellen i praksis død. Interessant nok er den samme
modellen også i ferd med å bli avviklet i Finland, slik at normalmodel-
len også der kan bli en folkevalgt flernivåforvaltning, som ellers i Europa
(Committee of Regions, 2019). Ved et veiskille? Så langt har framstillingen dreid seg om Agders representasjon i nasjonal
politikk og i noen grad om den nasjonale politikkens betydning for Agder. De siste årene har, som allerede påpekt, den regionale legitimeringen av 25 kapittel 1 nasjonal politikk blitt sterkt nedtonet (Knudsen, 2018; Teigen, 2012, 2019). Mye av dette har skutt fart etter suksessive omganger med avvikling av
eksplisitt politiske organer i de geografiske styringskjedene, til fordel for
ulike foretaksmodeller eller andre formalpragmatiske løsninger innenfor
ulike samfunnssektorer. Resultatet er at Norge i institusjonell sammen-
likning er blitt et mer liberalistisk land, også målt mot andre europeiske
land (Schneider & Paunescu, 2012). Sykehussektoren er et eksempel på
dette, universitets- og høgskolesektoren et annet. Et av resultatene av denne utviklingen er at politikken abdiserer, og at
den tradisjonelle påvirkning som utøves fra ulike regioner mot de nasjo-
nale beslutningsarenaene, ikke lenger virker. Helseministeren melder
pass overfor sykehusstrukturen og henviser i stedet til helseforetakene. Utdanningsstatsråden lar universitetsstyrene legge ned og kapre tidligere
høgskoler som de vil, mens kommunalministeren overlater utformingen
av kommunekartet til stemningen i den lokale nabopraten potensielle
fusjonspartnere imellom. I liberal sjargong heter det å styre via «arm’s
length» og i et geografisk vokabular benevnes det regionalliberalisme. Vi
kan jo bare tenke oss hva tidligere statsråder som Jens Chr. Hauge, Arne
Rettedal eller Gudmund Hernes ville ha sagt om de skulle bys slike ram-
mebetingelser for sitt virke. Det er blitt stuerent å være geografiløs. Som fenomen føyer det seg inn
i linjen av andre slike frikoplingsøvelser, som å være kulturløs og la insti-
tusjoner og regionale inndelinger få hete hva de vil. NSB blir til Vy. Oslo-
Met gjør krav på å betegne et universitet. Et nytt fylke får hete Vestland;
Fjordland var opptatt. Et annet fylke blir passe avsjelet til Innlandet – et
mulig kontrapunkt til Utlandet? I et slikt klima er det ikke så mye å hente
for en regional delegasjon ved å ta Sørtoget – som det nå er døpt – til Oslo
for å be makthavere uten makt om noe som helst.t Men ennå skal det visstnok hefte skam ved å være historieløs. Mon det. For i Norge er historie og geografi uløselig knyttet sammen. Regional-
som kunnskapspolitikken er blitt slik kirkepolitikken utviklet seg i etter-
krigstiden, da det gjaldt for statsrådene å være teologisk døve og blinde. Ved et veiskille? Nå har vi fått en styringskultur der det samme gjelder geografien, og det
er ikke bærekraftig, for å bruke en av tidens mest forslitte merkelapper. For å avslutte der jeg begynte – med Rokkan. Norge er som prosjekt et 26 regional representasjon i storting og regjering. hvor viktig er det? kompromiss mellom regionale interesser. Den som glemmer det, er dømt
til å mislykkes – i storting som i regjering. I dag er det min påstand at
mange i storting og styringsverk har mistet grepet om denne innsikten,
og at kommunevalget 2019 blant annet bar preg av det. Det skal mer til
for å rette opp det som her er skjedd enn å skysse en distriktsminister
med uklar portefølje inn i en regjering. Det handler heller om å gjenfinne
forståelsen av hvilket land vi bor i. Litteratur Bourdieu, P. (1995). Distinksjonen: en sosiologisk kritikk av dømmekraften Bourdieu, P. (1995). Distinksjonen: en sosiologisk kritikk av dømmekraften Bourdieu, P. (1995). Distinksjonen: en sosiologisk kritikk av dømmekraften
(A. Prieur, Overs.). Pax Forlag. (Opprinnelig utgitt 1979)
Brox, O. (1984). Nord-Norge: Fra allmenning til koloni. Universitetsforlaget.h (A. Prieur, Overs.). Pax Forlag. (Opprinnelig utgitt 1979) (A. Prieur, Overs.). Pax Forlag. (Opprinnelig utgitt 1979)
Brox, O. (1984). Nord-Norge: Fra allmenning til koloni. Universitetsforlaget. g
g
g
Brox, O. (1984). Nord-Norge: Fra allmenning til koloni. Universitetsforlaget. Castells, M. & Himanen, P. (2003). The information society and the welfare state. The Finnish model. Oxford University Press. Committee of Regions. (2019). Finland. https://portal.cor.europa.eu/divisionpowers/
Pages/Finland.aspx Erstad, E.A. (2019). Hareides fall. Trettiseks dagar som endra norsk politikk. Det Norske Samlaget. Garvik, O., Vetland, J. & Røiseland, M. (2003). Røiseland: statsministeren vi ikke fikk. Vigmostad & Bjørke. Granovetter, M. (1973). The strength of weak ties. American Journal of Sociology,
78(6), 1360–1380. https://doi.org/10.1086/225469 Habermas, J. (2002). Borgerlig offentlighet. Gyldendal. (Opprinnelig utgitt 1962) Hellevik, O. (1969). Stortinget – en sosial elite? En undersøkelse av sammenhengen
mellom sosial bakgrunn og politisk karriere. Pax Forlag. Hodne, F. (1981). Norges økonomiske historie 1815–1970. Cappelen. Hoel, O. L. (2009). Målreising og modernisering i Noreg 1885–1940
[Doktorgradsavhandling, Norges teknisk-naturvitenskapelige universitet]. NTNU
Open. http://hdl.handle.net/11250/242957
Johnsen, H. C. G., Dragseth, T., Johannessen, O. & Lysgård, H. K. (Red.). (2011). Kunstens form og kulturens bruk. Portal forlag. Knudsen, J. P. (2018). Towards a new spatial perspective – Norwegian politics at the
crossroads. Norsk Geografisk Tidsskrift – Norwegian Journal of Geography, 72(2),
67–81. https://doi.org/10.1080/00291951.2018.1445125 Hoel, O. L. (2009). Målreising og modernisering i Noreg 1885–1940
[Doktorgradsavhandling, Norges teknisk-naturvitenskapelige universitet]. NTNU
Open. http://hdl.handle.net/11250/242957
Johnsen, H. C. G., Dragseth, T., Johannessen, O. & Lysgård, H. K. (Red.). (2011). f
g
g
Knudsen, J. P. (2018). Towards a new spatial perspective – Norwegian politics at the
crossroads. Norsk Geografisk Tidsskrift – Norwegian Journal of Geography, 72(2),
67–81. https://doi.org/10.1080/00291951.2018.1445125 Knudsen, J. P. (2019). Reorganiseringen av UH-sektoren – nasjonsbygging med
regionsmak. I J. P. Knudsen & T. Lauvdal (Red.), Geografi, kunnskap, vitenskap. Den regionale UH-sektorens framvekst og betydning (s. 241–264). Cappelen Damm
Akademisk. 27 kapittel 1 Knudsen, J. P., Jacobsen, D. I. & Svendal, A. (1990). Sørlandsbilder. Tre scenarier for
Agder. Agderforskning. Linderot, L. (1985). Ingen vinner frem til den evige ro. I Norsk Salmebok, nr. 108. Verbum. (Opprinnelig utgitt 1798) Magone, J. M. (Red.). (2003). A Europe of regions: Rhetoric or reality? Praeger. Nielsen. M.-B. O. Litteratur (2001). Senterpartiets historie 1920–2000: Bd. 1. Bondekamp om
markedsmakt.1920–1959. Det Norske Samlaget. Norman, V.D., Røed, H. & Knudsen, J. P. (1994). Felles mål for Agder. KS.h Næss, P., Saglie, I.-L. & Halvorsen-Thorén, K. (2015). Ideen om den kompakte byen
i norsk sammenheng. I G. S. Hanssen, H. Hofstad & I. L. Saglie (Red.), Kompakt
byutvikling. Muligheter og utfordringer (kap. 3). Universitetsforlaget. hh Porter, M. E. (1990). The competitive advantage of nations. The Free Press.h Putnam, R. (2001). Bowling alone: The collapse and revival of American community. Simon & Schuster. Rasmussen, T. F. (1969). Byregioner i Norge. En samfunnsgeografisk analyse av den
regionale konsentrasjonen av bosettingsmønsteret i Norge (Rapport nr. 11). Norsk
institutt for by- og regionsforskning. Rasmussen. T. F. (2003). Bosetting og byutvikling. Planlegging og politikk i Norge
– i går, i dag, i morgen. Kommuneforlaget. Rimehaug, E. (1997). Midtbanespilleren. Kjell Magne Bondevik og Kristelig Folkeparti. Luther. Rimehaug, E. (1997). Midtbanespilleren. Kjell Magne Bondevik og Kristelig Folkeparti. Luther. Rokkan, S. (1966). Norway: Numerical democracy and corporate pluralism. Rokkan, S. (1966). Norway: Numerical democracy and corporate pluralism. I R Dahl (Red ) Political opposition in western democracies Yale University I R. Dahl (Red.), Political opposition in western democracies. Yale University Press. I R. Dahl (Red.), Political opposition in western democracies. Yale University Press. Rokkan, S. (1967). Geography, religion and social class: Cross-cutting cleavages in
Norwegian politics. I S. M. Lipset & S. Rokkan (Red.), Party systems and voter
alignments: Cross-nationalpPerspectives (s. 367–444). The Free Press. Rokkan, S. (1967). Geography, religion and social class: Cross-cutting cleavages in
Norwegian politics. I S. M. Lipset & S. Rokkan (Red.), Party systems and voter
alignments: Cross-nationalpPerspectives (s. 367–444). The Free Press. Røed, H., Knudsen, J. P. & Fosse, J. K. (2002). Robuste regioner – forskning og reform
(Prosjektrapport 45/2002). Agderforskning. Schneider, M. R & Paunescu, M. (2012). Changing variety of capitalism and revealed
comparative advantages from 1990–2005. A test of the Hall & Soskice claims. Socio-Economic Review, 10(4), 731–753. https://doi.org/10.1093/ser/mwr038 Sejersted, F. (2002). Demokratisk kapitalisme. Revidert utvalg. Pax Forlag. Selstad, T. (1983). Mjøsbyen. Morgendagens storby ved Mjøsa? Fagbokforlaget/
Mjøsinfomasjon. Slagstad, R. (1998). De nasjonale strateger. Pax Forlag. St. meld. nr. 44 (1982–83). Om maktutredningen. Statsministeren. https://
www.stortinget.no/no/Saker-og-publikasjoner/Stortingsforhandlinger/
Lesevisning/?p=1982-83&paid=3&wid=d&psid=DIVL172&pgid=d_0077 St. meld. nr. 44 (1982–83). Om maktutredningen. Statsministeren. https://
www.stortinget.no/no/Saker-og-publikasjoner/Stortingsforhandlinger/
Lesevisning/?p=1982-83&paid=3&wid=d&psid=DIVL172&pgid=d_0077 28 regional representasjon i storting og regjering. hvor viktig er det? regional representasjon i storting og regjering. hvor viktig er det? Stugu, O. S. (2015). Etterkrigstidas kommunereform – eit oversyn. Heimen, Stugu, O. S. (2015). Etterkrigstidas kommunereform – eit oversyn. Heimen,
52(4), 311–325. https://www.idunn.no/heimen/2015/04/etterkrigstidas_
kommunereform_-_eit_oversyn Teigen, H. (2012). Distriktspolitikk gjennom 50 år – strategane og avviklinga. Nytt Norsk Tidsskrift, 29(2), 157–165. https://www.idunn.no/nnt/2012/02/
distriktspolitikk_gjennom_50_aar_-_strategane_og_avviklinga Teigen, H. (2019). Distriktspolitikkens historie i Norge. Cappelen Damm Akademisk. Aardal, B. (Red.) (2011). Det politiske landskap. En studie av stortingsvalget i 2009. Cappelen Damm Akademisk. 29 kapittel 2 Sitering av dette kapitlet: Tronstad, R. (2020). Kristiansands rolle som regionalt styringssentrum i peri-
oden 1641–1919. I Johnsen, B.E. og Vadum, K. (red.), Grenseløst Agder. Det som skilte og det som bandt
(s. 30–54). Oslo: Cappelen Damm Akademisk. https://doi.org/10.23865/noasp.111
Lisens: CC BY-NC-ND. Kristiansands rolle som
regionalt styringssentrum i
perioden 1641–1919 Roger Tronstad Fra 1. januar 2016 ble Fylkesmannen i Aust-Agder og Fylkesmannen
i Vest-Agder slått sammen til ett embete – Fylkesmannen i Aust- og
Vest-Agder. Fra 1. januar 2019 ble den sistnevnte betegnelsen endret til
Fylkesmannen i Agder. Ikke bare på statlig plan ble det nylig en endring
– fra 1. januar 2020 ble de to fylkeskommunene slått sammen til Agder
fylkeskommune, og dermed utgjør Aust-Agder og Vest-Agder ett fylke
– Agder. Fra 1. januar 2016 ble Fylkesmannen i Aust-Agder og Fylkesmannen
i Vest-Agder slått sammen til ett embete – Fylkesmannen i Aust- og
Vest-Agder. Fra 1. januar 2019 ble den sistnevnte betegnelsen endret til
Fylkesmannen i Agder. Ikke bare på statlig plan ble det nylig en endring – fra 1. januar 2020 ble de to fylkeskommunene slått sammen til Agder
fylkeskommune, og dermed utgjør Aust-Agder og Vest-Agder ett fylke
– Agder. I prosessen fram mot disse endringene har det vært mange diskusjo-
ner. Et av stridstemaene har vært om Agder skulle danne ett fylke alene
eller være en del av et større fylke. Et annet tema har vært hvor admi-
nistrasjonssetet for fylkeskommunen skulle ligge. Også i forbindelse
med det nye fylkesmannsembetet for både Aust-Agder og Vest-Agder
fra 1. januar 2016 ble det diskusjoner om hvor virksomheten skulle loka-
liseres. Skulle hele fylkesmannsvirksomheten ligge ett sted og hele det
fylkeskommunale organet ett sted, eventuelt i samme by, eller skulle
hvert av de to organenes funksjoner fordeles på to steder, for eksempel
Arendal og Kristiansand? I dette kapitlet skal vi rette søkelyset mot en lang tidsperiode da Agder
var en del av en større administrativ region, samtidig som Kristiansand
var regionens hovedstad. Ved inngangen til 1600-tallet var Norge i geist-
lig henseende inndelt i fire regioner, det vil si bispedømmer eller såkalte 30 kristiansands rolle som regionalt styringssentrum stift. Agder var en del av det sørligste stiftet. Under eneveldet oppsto også
andre typer stiftsomfattende, offentlige virksomheter rundt om i landet. Vi skal ta for oss perioden fra 1641, da Kristiansand ble grunnlagt, og
fram til 1919, da stiftamtmannsembetet forsvant og amtene skiftet navn. Med utgangspunkt i stiftsomfattende virksomheter som Agder var en del
av, er hovedspørsmålet i dette kapitlet: Hvilken rolle hadde Kristiansand
som administrasjonssentrum i Norges sørligste region i perioden? Kristiansands rolle som
regionalt styringssentrum i
perioden 1641–1919 Det
faller utenfor oppgaven å drøfte hvordan de forskjellige organene kom til
å fungere i praksis, da dette ville ha medført svært tidkrevende under
søkelser og sprengt de fysiske rammene for kapitlet. Noen få eksempler
på konflikter skal likevel nevnes. g
y
g
g
2
I 1864 ble også de to andre prostiene i Telemark, nemlig Nedre Telemark og Bamble, lagt til
stiftet, som da het Kristiansand. Kongelig resolusjon 27.02.1864. 1
Kongebrev 10.04.1631, trykt i Norske Rigs-Registranter, bd. 6, 1628–1634, s. 309. Bakteppet for Kristiansands rolle Først skal vi se på perioden som dekker en mannsalder før og etter Kris-
tiansands grunnleggelse. Vi skal fokusere på begrepene stift og stiftamt,
siden de er sentrale for forståelsen av regionen som Agder var en del av. På 1500-tallet, og lenge før det, lå Agder under Stavanger stift, og bispe-
setet var da i Stavanger. Til stiftet hørte dagens Agder og Rogaland, og i
tillegg Hallingdal prosti med prestegjeldene Eidfjord, Ål og Nes, og Val-
dres prosti med prestegjeldene Aurdal, Slidre og Vang. På 1600-tallet kom
flere endringer av stiftets utstrekning. Det begynte i 1608, da prestegjeldet
Eidfjord ble overført til Hardanger prosti i Bergen stift. Stavanger stift ble
da tydelig splittet i to geografisk atskilte deler. I 1605 ble Laurits Claus-
søn Schouboe, i latinisert form også kalt Laurentius Claudii Scavenius,
biskop i Stavanger. Han sørget for at det for første gang ble tegnet et kart
over Stavanger stift. Det skjedde i ca. 1618. Den opprinnelige versjonen
av kartet, som var tegnet av eller i samarbeid med Scavenius, har seinere
gått tapt. Kartet kan ha vært laget delvis på grunnlag av biskopens obser-
vasjoner på visitasreiser. Det ble trykt i flere omganger og versjoner i lang
tid etter 1618, blant annet hos Johannes & Cornelis Blaeu i Amsterdam. På kartet ser man tydelig hvor atskilt Hallingdal og Valdres ble betraktet
fra resten av Stavanger stift. 31 kapittel 2 Scaveniuskartet, trykt i 1638 av Joan og Cornelis Blaeu. Kilde: Koninklijke Bibliotheek, Amsterdam. Scaveniuskartet, trykt i 1638 av Joan og Cornelis Blaeu. Kilde: Koninklijke Bibliotheek, Amsterdam. For biskopen i Stavanger var det besværlig å foreta inspeksjonsreiser til
Hallingdal og Valdres. I 1631 kom en større forandring for å gjøre det lettere
for biskopen. Da ble prostiene Hallingdal og Valdres overført til Oslo stift. Til gjengjeld ble Øvre Telemark prosti overført fra Oslo stift til Stavan-
ger stift.1 Etter at byttet av prostier ble gjennomført i 1631, fortsatte likevel
Scavenius-kartene å bli utgitt i lang tid etter med de gamle stiftsgrensene,
men kartene viste i hvert fall hvordan grensene hadde vært før 1631. Byttet
av Hallingdal og Valdres mot Øvre Telemark er den mest dramatiske end-
ringen, geografisk sett, for det sørligste stiftet i perioden 1600–1900.2 Det er
uvisst hvorfor en slik naturlig løsning ikke var valgt lenge før 1631. Bakteppet for Kristiansands rolle 32 kristiansands rolle som regionalt styringssentrum Byttet av prostier kan godt ses på som en forskyving av tyngdepunktet
i stiftet fra vest mot øst, i hvert fall geografisk. Snart skulle også det admi-
nistrative tyngdepunktet bli flyttet i samme retning. Etter at Kristiansand
var grunnlagt i 1641, begynte sentralmyndighetene å tenke på hvordan
byen kunne stimuleres til befolkningsmessig og økonomisk vekst og
betydning. I 1662 ba byens deputerte – de eligerte menn – om at Stavan-
ger domkapittel måtte flyttes til Kristiansand.3 Det var imidlertid litt tid-
lig for myndighetene å gi den nye byen en regional administrativ rolle. I 1662 ble det bestemt at betegnelsen «amt» skulle tas i bruk i stedet
for «len».4 I praksis ble amtene likevel ofte kalt len og amtmennene for
lensherrer eller befalingsmenn i flere år etter 1662. I en overgangsperiode
fra 1662 til 1671 var det delvis én amtmann for Nedenes, Råbyggelaget og
Mandal og én amtmann for Lister.5 Disse herrene bodde imidlertid ikke i
regionen. I 1667 klaget Agdesidens lagmann over at det ikke bodde noen
amtmann i Kristiansand.6 Betegnelsene lensherre og befalingsmann gikk nokså konsekvent over
til å bli «amtmann» fra 1671. Det skyldes at en ny type befalingsmann ble
opprettet det året. I 1671 oppsto nemlig stiftamtene, som var et forvalt-
ningsnivå over – og større enn – amtene. Da ble det etablert fire regionale
«Stift- eller Hoved-Amter» i Norge. Det sørligste stiftamtet skulle hete
«Christianssands eller Agdesidens Hoved-Amt» og skulle også omfatte
Stavanger amt, det vil si Rogaland, og Bratsberg amt, det vil si Telemark.7
«Agdesiden» var også betegnelsen på hovedlenet, som i første halvdel
av 1600-tallet omfattet dagens Agder-fylke. Betegnelsen ble også brukt
om lagdømmet, som på 1600- og 1700-tallet likeledes omfattet Agder. Betegnelsene lensherre og befalingsmann gikk nokså konsekvent over
til å bli «amtmann» fra 1671. Det skyldes at en ny type befalingsmann ble
opprettet det året. I 1671 oppsto nemlig stiftamtene, som var et forvalt-
ningsnivå over – og større enn – amtene. Da ble det etablert fire regionale
«Stift- eller Hoved-Amter» i Norge. Det sørligste stiftamtet skulle hete
«Christianssands eller Agdesidens Hoved-Amt» og skulle også omfatte
Stavanger amt, det vil si Rogaland, og Bratsberg amt, det vil si Telemark.7 «Agdesiden» var også betegnelsen på hovedlenet, som i første halvdel
av 1600-tallet omfattet dagens Agder-fylke. Betegnelsen ble også brukt
om lagdømmet, som på 1600- og 1700-tallet likeledes omfattet Agder. 3
Steen 1941: 140
4
Mykland 1977: 121
5
Weidling 2000: 31
6
Steen 1941: 138
7
Reskript 08.02.1671, trykt i: a) Kongelige Rescripter I, s. 46; b) Kongelige Rescripter III, s. 70;
c) Samling af Norge vedkommende Kgl. Rescripter, Resolutioner og Collegialbreve m.v. for Tids-
rummet fra 1660 til 1813, forsaavidt de kunne ansees at være af Vigtighed for den Lovstuderende
og den juridiske Embedsmand i Almindelighed. Udtogsviis udgiven af F. Stang, B. Dunker, s. 15. 8
«Statholder Gyldenløves og Jørgen Bjelkes Betænkning angaaende Norges Administration
1670», trykt i Meddelelser fra det norske Rigsarchiv, første bind, s. 386.
9
Weidling 2000: 22, 34, 38 ddelelser fra det norske Rigsarchiv, første bind, s. 386. Bakteppet for Kristiansands rolle Hovedamtene falt i hovedsak sammen med bispedømmenes grenser. Siden
den vanlige betegnelsen på bispedømme var stift, kom hovedamtene etter
hvert til å bli kalt stiftamt. Det vanlige navnet på det sørligste hovedamtet ble 33 kapittel 2 etter hvert «Christiansands stiftamt». Vi kan legge merke til at hovedamtet
ikke skulle hete Stavanger, slik som stiftet het ennå i 1670-årene, men Kris-
tiansand eller Agdesiden. Det var altså den verdslige overøvrighetsregionen
som var først ute med å hete Kristiansand i stedet for Stavanger. Bestemmel-
sen i 1671 om å opprette et «Christiansands stiftamt» kan ses på som et første
ledd i å oppgradere den unge agderbyen regionaladministrativt.tt Ifølge 1671-bestemmelsen skulle lederen for stiftamtet ha tittelen stifts-
befalingsmann, men etter hvert ble betegnelsen stiftamtmann også brukt. Stiftamtmannen skulle ha 1000 riksdaler i årslønn, mens hver amtmann
skulle ha 500 riksdaler. Avlønningen illustrerer at stiftamtmannen sto
over amtmannen i rang og myndighet. I 1670 fikk stattholder Ulrik Frederik Gyldenløve og generalløytnant
Jørgen Bjelke i oppdrag å utarbeide et forslag til administrativ struktur
for Norge, blant annet inndeling i amt. Den nevnte bestemmelsen i 1671
var i tråd med de to herrenes forslag med hensyn til inndeling i hovedamt
og amt. Forslaget gikk også ut på at Ove Juel skulle bli stiftamtmann i
Kristiansands hovedamt og «… formedelst Correspondencen saa og
Kongl. Majtt.s Interesse og Stedens samt Trafiqvens Importants at resi-
dere udi Christianssand».8 Det ser ut til at Kristiansands geografiske og
strategiske plassering var grunnen til at Gyldenløve og Bjelke fant det
påkrevd at stiftamtmannen skulle bo der. Fra 1671 ble faktisk Ove Juel den første stiftsbefalingsmannen i Kris-
tiansand hovedamt. Han bodde riktignok verken i Kristiansand eller
Stavanger, men på Akershus, siden han også var visestattholder i Norge. Juel gikk av som stiftamtmann i Kristiansand i 1679.9 I 1680 ble amtman-
nen i Stavanger, baron Ludvig Holgersen Rosenkrantz, utnevnt som ny
stiftamtmann. Han skulle være både stiftamtmann og – i hvert fall fore-
løpig – amtmann i Stavanger amt med bosted i Stavanger. Året etter til-
trådte Jacob Jenssøn Jersin som biskop i Stavanger. Forholdet mellom stiftamtmann og biskop var ikke nødvendig-
vis alltid avklart eller hjertelig. Konflikter om rang kunne forekomme. I 1682 tilspisset dette seg i en delikat episode. Bakgrunnen for dette var 34 kristiansands rolle som regionalt styringssentrum formalitetene rundt saksområder som biskop og stiftamtmann hadde fel-
les, som for eksempel kirkeadministrative spørsmål i hele stiftet. 11
Riksarkivet, Danske Kanselli, Fcca, 0035 Norske innlegg 1682–1683, s. 52. Brev 08.04.1682 fra
Rosenkrantz til Danske Kanselli. 10
Riksarkivet, Danske Kanselli, Skapsaker, F, 0066 Skap 14, pakke 324–333, 1623–1686, s. 144. Brev
27.10.1681 fra Rosenkrantz til Danske Kanselli. 10
Riksarkivet, Danske Kanselli, Skapsaker, F, 0066 Skap 14, pakke 324–333, 1623–1686, s. 144. Brev
27.10.1681 fra Rosenkrantz til Danske Kanselli.
11
Riksarkivet, Danske Kanselli, Fcca, 0035 Norske innlegg 1682–1683, s. 52. Brev 08.04.1682 fra
Rosenkrantz til Danske Kanselli. 10
Riksarkivet, Danske Kanselli, Skapsaker, F, 0066 Skap 14, pakke 324–333, 1623–1686, s. 144. Brev
27.10.1681 fra Rosenkrantz til Danske Kanselli.
11
Riksarkivet, Danske Kanselli, Fcca, 0035 Norske innlegg 1682–1683, s. 52. Brev 08.04.1682 fra Bordplassering i kapittelsalen i Sjælland stift. Kilde: Riksarkivet, Danske Kanselli, Fcab, 0012 Norske tegnelser 1670–1683, Bakteppet for Kristiansands rolle I en del
slike saker pleide stiftamtmannen og biskopen å være til stede i dom-
kapitlet, som var et kollegium av først og fremst geistlige. Denne typen
møte, som på dansk het «landemode», skulle presideres, det vil si ledes,
av Rosenkrantz. Møtene pleide å bli holdt i det såkalte kapittelshuset ved
domkirka.10 I april 1682 hadde kapitlet et slikt møte. Før møtet, mens
Rosenkrantz var en tur i Holland, hadde biskop Jersin gjort møtebordet
breiere, og under møtet plasserte han seg rett ved siden av Rosenkrantz,
som var den øverste av de to, formelt sett. Dette likte ikke Rosenkrantz,
som skrev til kongen at han syntes stiftamtmannen burde presidere alene
«til Eders Kongl. Mayts. Høye Respect».11 Bordplassering i kapittelsalen i Sjælland stift. Kilde: Riksarkivet, Danske Kanselli, Fcab, 0012 Norske tegnelser 1670–1683,
f l
V dl
til
i
i
6 68 til R
k
t
J
i Kilde: Riksarkivet, Danske Kanselli, Fcab, 0012 Norske tegnelser 1670–168 fol. 314a–315a. Vedlegg til missiv 10.06.1682 til Rosenkrantz og Jersin. 35 kapittel 2 Kongen svarte i juni at bordplasseringen skulle være slik som i Sjællands
stift, og som framgikk av en vedlagt skisse.12 Skissen viser plasseringen av
de fire høyere embetsmennene, nemlig stiftsbefalingsmannen i Sjælland,
biskopen i Sjælland, stiftsprosten og magister Christen Lodberg. Sist-
nevnte var en framstående dansk teolog. Bordet var ovalt, og ingen satt
egentlig rett ved siden av en annen, men spredt rundt bordet. Langs veg-
gene satt prostene. Her kan det nevnes at biskopene som kongen utnevnte
til Norge under eneveldet, ble vigslet og innsatt i embetet av biskopen i
Sjælland i København.13 12
Riksarkivet, Danske Kanselli, Fcab, 0012 Norske tegnelser 1670–1683, fol. 314a–315a. Missiv
10.06.1682 til Rosenkrantz og Jersin.
Kiil
6
8 15
Riksarkivet, Danske kanselli, Fcab, 0012 Norske tegnelser 1670–1683, fol. 309b–310a. Missiv
06.05.1682 til Rosenkrantz og Jersin. 14
Riksarkivet, Danske Kanselli, Fcca, 0040 Norske innlegg 1572–1799, 1686–1687, s. 35–40.
Mechlenburgs memorial februar 1682. 13
Kiil 1969: 58 Kristiansand blir stiftsby Omtrent samtidig med bord-episoden oppsto en annen situasjon som
kom til å berøre ikke bare Rosenkrantz og Jersin, men i høyeste grad også
Kristiansand by. På nyåret i 1682 ble det fart i arbeidet med å utrede Kristiansand som
stiftshovedstad. Som svar på en henvendelse fra Rentekammeret til
magistraten i Kristiansand, leverte borgermester Carsten Mechlenburg
en redegjørelse for byherrenes synspunkt. Mechlenburg kalte Stavanger
for «en aldrende Bye», og foreslo at Kristiansand ble sete for blant annet
stiftamtmannen.14 I mai 1682 traff kongen avgjørelsen som endret Kristi-
ansands status.15 Bestemmelsen innebar følgende fire punkter: • Stavanger stift skulle hete Kristiansand stift • domkapitlet og latinskolen skulle holde til i Kristiansand • Kristiansand kirke skulle få status som domkirketl • stiftamtmannen og biskopen skulle flytte fra Stavanger til Kristiansand • stiftamtmannen og biskopen skulle flytte fra Stavanger til Kristiansand 36 kristiansands rolle som regionalt styringssentrum Nå skulle altså stiftet hete Kristiansand, slik som stiftamtet het fra 1671. Det
var to uttrykkelige begrunnelser for vedtaket om å forandre byens status: Nå skulle altså stiftet hete Kristiansand, slik som stiftamtet het fra 1671. Det
var to uttrykkelige begrunnelser for vedtaket om å forandre byens status: • for at Kristiansand «des meere maa tiltage», det vil vel si å vokse i
størrelse og velstand • for at geistlige og verdslige undersåtter i stiftet skulle ha nærmere
til «at søge deris ret» Det sistnevnte må bety at når den administrative plasseringen var midt
på Agder-kysten, så ble det ikke så langt å reise fra lengst øst i regionen
når noen trengte hjelp av stiftsinstanser som hadde tilhold i Kristian
sand. Riktignok ville det bli lenger å reise for de som bodde i Stavanger
amt, men nå skulle jo Kristiansand prioriteres. I tillegg kan det ha vært forsvarsstrategiske motiver bak kongens
avgjørelse. I 1660–1680-årene ble festningsverkene på Christiansholm,
Odderøya, Dybingen og Lagmannsholmen bygd ut. Sverre Steen skriver
at Kristiansand ble regnet som en av rikets hovedfestninger fra 1670, ved
siden av Akershus og Bergenhus. Han minner også om at byen i 1685 ble
fast havn for kystkrigsflåten og fikk et kongelig skipsverft.16 Baron Rosenkrantz hadde ikke lyst til å flytte til Kristiansand i 1682. Han var godt etablert i Stavanger som stiftamtmann og amtmann og
hadde godset sitt på Vestlandet, blant annet Rosendal. Jersin på sin side
hadde flyttet fra Danmark til Stavanger året før, og hadde ikke lyst til å
flytte igjen allerede. 17
Riksarkivet, Danske kanselli, Fcab 0012 Norske tegnelser 1670–1683, fol. 386a–b. Missiv
29.03.1683 til Rosenkrantz og Jersin. 18
Steen 1941: 141 16
Steen 1941: 141–142 16
Steen 1941: 141–142
17
Riksarkivet, Danske kanselli, Fcab 0012 Norske tegnelser 1670–1683, fol. 386a–b. Missiv
29.03.1683 til Rosenkrantz og Jersin.
18
Steen 1941: 141 Kristiansand blir stiftsby En av grunnene kan ha vært at det meste av bispesto-
lens benefiserte gods lå i Ryfylke og på Jæren. Men kongen hadde forutsatt
at begge skulle flytte det året. I mars 1683 bodde både Rosenkrantz og Jer-
sin fremdeles i Stavanger. Det likte ikke kongen, som nå måtte minne om
bestemmelsen fra mai 1682. Kongen befalte stiftamtmannen og biskopen å
flytte til Kristiansand, og det innen pinse i 1683.17 Det nyttet ikke at Rosen-
krantz klaget over at Kristiansand var «en skarp og mager ort».18 Rosen-
krantz flyttet til Kristiansand det året, mens Jersin drøyde til høsten 1684, 37 kapittel 2 muligens etter den store bybrannen i Stavanger 4. november. Dermed var
begge bosatt i Kristiansand da Kristian 5. besøkte byen i juli i 1685. Den katastrofale brannen i Stavanger i 1684 må ha bidratt til at Kristian
sand fikk en sterkere posisjon som hovedby i stiftet. Stavanger var for øvrig
nedgradert fra en status som kjøpstad til å være ladested i årene 1686–1690. Kristiansand hadde nå blitt stiftsby og ble for så vidt en av Norges fire
viktigste byer. Den var likevel den minste av stiftsbyene, og Kristiansand
stift var det minste stiftet. For eksempel var Akershus stift tre ganger så
stort i folketall i 1801, og dobbelt så stort i areal. Gjennom 1700-tallet vokste
imidlertid Kristiansand og ble større enn Stavanger i folketall. Man regner
med at Kristiansand og Stavanger kan ha hatt rundt 1500 innbyggere hver i
1660-årene. I 1801 hadde folketallet økt til ca. 2500 i Stavanger og nær 5000
i Kristiansand.19 Flyttingen av stiftssetet i 1680-årene hadde nok likevel
ikke så stor virkning for agderbyens folketall som ønsket. I hundreårs
perioden fram til 1780 økte nemlig folketallet bare til ca. 3000 personer. I
1790 var folketallet 3600–3700. Det var i 1790-årene at den største veksten
kom. Sverre Steen forklarer dette først og fremst med høykonjunkturer
fra 1790-årene, da krigene i Europa startet, og – som en konsekvens – økt
tilflytting av yngre, arbeidsføre mennesker fra bygdene til byen.20 19
Norges historie, bind 15, Historisk atlas, oversikter, register, s. 220.
20
Steen 1941: 382–383, 434–436
21
Steen 1941: 561 19
Norges historie, bind 15, Historisk atlas, oversikter, register, s. 220. 20
Steen 1941: 382–383, 434–436 23
Riksarkivet, Danske kanselli, Fcab, 0012 Norske tegnelser 1670–1683, fol. 441b–442a. Missiv
17.11.1683 til stattholder Ulrik Frederik Gyldenløve. 22
Leewy 1956: 64 Kilde: Norsk historisk leksikon, Cappelen Akademisk Forlag as, Oslo 1999, s. 17. 22
Leewy 1956: 64 Amtene i Norge i 1680. Amtene i Norge i 1680.
Kild
N
k hi t
i k l k ik
C
l
Ak d
i k F
l
O l Overøvrigheten i Kristiansand Et synlig kjennetegn på at Kristiansand var stiftshovedstad fra 1680-årene,
var at de to såkalte overøvrighetspersonene residerte der. Kongen hadde
kjøpt eiendom til stiftamtmannen og biskopen da de to flyttet til Kristian
sand. Begge eiendommene hadde store bygninger og lå ved krysset Elve-
gata/Kongens gate. Kongen hadde gitt 2000 riksdaler for eiendommen som
stiftamtmannen skulle ha, mens biskopens residens kostet 700 riksdaler.21
I 1812 kjøpte staten en grunneiendom ved krysset Dronningens gate/Kirke-
gata. Der ble det oppført et stort trehus som stiftamtmennene bodde i fram
til huset gikk tapt i bybrannen i 1892. Boligen som biskopen fikk i 1680-årene, 38 kristiansands rolle som regionalt styringssentrum ble fort skrøpelig og måtte fraflyttes og rives på slutten av 1700-tallet.22 Gjen-
nom 1800-tallet bodde biskopene forskjellige steder i byen. Hver av stiftamtmennene i Norge kunne være amtmann samtidig i ett
av amtene i stiftet, og da ikke nødvendigvis det amtet som han bodde i. Da stiftamtmann Rosenkrantz bosatte seg i Kristiansand, ble han også
amtmann i Lister og Mandal amt i stedet for Stavanger amt. Mannen som
var amtmann i Lister og Mandal, måtte derfor avstå dette amtet, og fikk
i stedet Stavanger amt. Dette bestemte kongen i november 1683.23 Rosen-
krantz hadde denne doble funksjonen til han døde i Kristiansand i 1685. Ellers hadde Lister og Mandal sin egen amtmann fra 1671 og helt til 1815. 39 kapittel 2 For Nedenes ble det annerledes. I årene 1671–1679 var stiftamtmann Ove
Juel også amtmann i Nedenes. Dette skulle bli en langvarig ordning. Riktignok hadde Nedenes i en mellomperiode fra 1680 til 1689 en egen
amtmann. Men fra 1689 var stiftamtmann Christian Stockfleth også amt-
mann i Nedenes, og denne ordningen kom nå til å vare helt til 1815.it I 1691 fikk stiftamtmannen i Kristiansand en arbeidsinstruks av kon-
gen. En av oppgavene som stiftamtmann var å inspisere og bistå amt-
mennene og kontrollere andre sivile embets- og tjenestemenn i stiftet. En annen oppgave var å ha oppsyn med justisvesenet og dets embets- og
tjenestemenn. En tredje var å ha et våkent øye for blant annet handel,
fiskeri og industri. En fjerde myndighetsoppgave var å være overøvrighet
over byene i hele stiftet.24 Vi kan nevne et konkret eksempel på utfall av oppgaven med å kontrol-
lere embetsmenn. En av de mest brysomme embetsmennene i stiftamtet,
og faktisk i hele Norge, på 1700-tallet var Mauritz Anthoni Schweder. 24
Instruks 24.11.1691, trykt i Aarsberetninger fra Det Kongelige Geheimearchiv, indeholdende Bidrag
til dansk Historie af utrykte Kilder. Udgivne af C.F. Wegener. Andre bind, s. 318–321.
25
Finne-Grønn 1932: 197–198
26
Steen 1941: 464 24
Instruks 24.11.1691, trykt i Aarsberetninger fra Det Kongelige Geheimearchiv, indeholdende Bidrag
til dansk Historie af utrykte Kilder. Udgivne af C.F. Wegener. Andre bind, s. 318–321. 25
Finne-Grønn 1932: 197–198
26
Steen 1941: 464 Overøvrigheten i Kristiansand I 1764 ble han utnevnt til byfogd i Kristiansand, og i 1767 ble han også
politimester i samme by. Schweder var en hensynsløs og usedvanlig kve-
rulantisk embetsmann. Da det ble klart at han gikk fysisk hardt fram
for å presse penger ut av folk for påståtte eller bagatellmessige forseelser,
måtte Hans Hagerup, stiftamtmann 1767–1781, sende inn en klage til
sentralmyndighetene. Det ble nedsatt en kommisjon, som ila Schweder
høye bøter. Schweder anket. Saken endte med at Høyesterett fradømte
Schweder embetet både som byfogd og politimester i 1773.25 Dette var for
øvrig ikke den eneste problemsaken som Hagerup fikk med Schweder. Når det gjelder rollen som overøvrighet over byene, hadde ikke
stiftamtmannen styrings- eller bestemmelsesrett, men han kunne følge
med, gi råd og være kontaktperson. Borgerne hadde selvstyre i egen by. Hvis det var uenighet mellom en bys organer, og de ikke ville respektere
stiftamtmannens syn, måtte han gi opp eller søke kongens avgjørelse.26
Det er mange eksempler på dette, men ikke på at stiftamtmennene på
eget initiativ har blandet seg inn i byenes affærer for å avgjøre saker. 40 kristiansands rolle som regionalt styringssentrum Henrik Adelaer, stiftamtmann 1711–1718, krevde riktignok å få godkjenne
byregnskapene før de ble sendt til Rentekammeret. Det fant magistraten
krenkende, men stiftamtmannen var i sin fulle rett når han ville kon-
trollere magistratens regnskaper.27 Stiftamtmann Hagerup ga ordre til
magistraten i Kristiansand i mars 1771 om å undersøke hvor stor korn-
beholdningen var i byen.28 Dette var imidlertid ikke å blande seg inn i
magistratens affærer, men må heller ses på som behov for hjelp til å få en
god oversikt i en uvanlig kald ettervinter med islagt havn og lite korn. Det at stiftamtmennene ga såkalte ordre til magistraten, innebar ikke at
de dermed overprøvde magistratens gjøren og laden. En av dem som kom nærmest opp til konflikt med magistraten, var
nok Hans Christopher Diederich Victor von Levetzow, stiftamtmann
1790–1800. I 1786 ble antall deputerte borgere i Kristiansand redusert
fra tolv til fire. I 1793 ba de fire deputerte om avløsning. Inntil da hadde
byborgerne selv valgt hvem som skulle være de eligerte menn, men nå
ville magistraten overta retten til å foreta valget. Da satte Levetzow foten
ned. I et meget skarpt brev til magistraten ga han en nøyaktig instruks
for hvordan valget skulle foregå. Magistraten måtte bøye seg for stiftamt-
mannens ordre om at det fortsatt var byborgerne som skulle bestemme
dette. 27
Friis 1941: 25
28
Friis 1941: 77
29
Friis 1941: 103–105 Overøvrigheten i Kristiansand Da de nye deputerte fikk problemer med å få utlevert nødvendige
dokumenter fra byens arkiv, måtte Levetzow igjen trå til med å gi magist
raten pålegg, denne gang om å la de deputerte få se registraturen over
arkivet, slik at de kunne rekvirere det de ønsket å se.29 Enkelte ganger forekom det gnisninger innen magistraten og dens
medhjelpere. En av magistratens sekretærer var rådstueskriveren. Som
sådan førte han protokollene for rådstueretten, hvor magistraten satt og
dømte i ankesaker. I Kristiansand var denne funksjonen kombinert med
å være byskriver, det vil si sekretær for førsteinstansen byretten, som var
administrert av byfogden. Fra 1763 til 1799 var Henrik Arnold Thaulow
by- og rådstueskriver i Kristiansand. I tillegg var han skriver i flere andre
sammenhenger, blant annet i politiretten og brannretten. Som skriver
hadde han adgang til byens arkiver. Både før og under Thaulows tid var 41 kapittel 2 det gnisninger mellom magistraten og by- og rådstueskriveren når det
kom til ansvar og adgang til byens arkiver og segl. Et annet forhold som
Thaulow var oppgitt over, var at han ble pålagt altfor mange oppgaver av
magistraten. Dessuten hadde magistratsherrene fått laget seg hvert sitt
rådstuesegl, og i tillegg ble det utstedt mange bestallinger på magistrats-
fullmektiger og -betjenter som fikk økonomiske fordeler, ifølge Thaulow,
og titler som for eksempel stiftsfullmektig, viserådmann og magasinfor-
valter. Thaulow følte at han på denne måten ble neglisjert med hensyn
til kompetanse, ansvar og avlønning. Derfor tok han opp saken med
stiftamtmann Hagerup, som også innhentet magistratens syn. Magistra-
ten minte om at Thaulows forgjenger hadde ansatt to fullmektiger for å
avhjelpe seg.30 Det ser ikke ut til at saken innebar annet enn at stiftamt-
mannen ble brukt som kontaktperson og klagemur. Muligens kan han ha
dempet gnisningene ved å ha meglingsmøter med de involverte. Gjennom 1700-tallet ble skillet mellom stiftamtmann og amtmann
utvisket. Fra 1815 ble byene underlagt nærmeste amtmann i stedet for
stiftamtmann. Dessuten utførte jo stiftamtmannen alle amtmanns
oppgavene i egenskap av amtmann i sin del av stiftamtet. I den drøye hundreårsperioden fra 1689 til 1815 måtte stiftamtmannen
dra fra hjemstedet i Kristiansand og østover i stedet for vestover når han i
egenskap av amtmann i Nedenes skulle besøke amtet sitt, men det betydde
antakelig ikke noen forskjell så lenge han bodde midt på Agder-kysten. 31
Kongelig resolusjon 16.03.1815. Byttet skjedde fra 22.05.1815. 30
Tronstad 2008: 33–37 30
Tronstad 2008: 33–37 Overøvrigheten i Kristiansand I 1815 vedtok kongen en justering og presisering av jurisdiksjons
områdene til landets stiftamtmenn og amtmenn.31 For Agder innebar
endringen for det første at stiftamtmannen i Kristiansand, som hittil også
hadde vært amtmann i Nedenes, i stedet skulle være amtmann i Lister og
Mandal i tillegg til stiftamtmannsrollen, altså tilbake til ordningen fra
1680-årene. Stiftamtmannen skulle fortsatt ha bosted i Kristiansand, som
jo lå i Lister og Mandal amt. For det andre skulle den daværende amtmannen i Lister og Mandal
overta Nedenes amt og ha bopel i eller ved Arendal. Stiftamtmann Oluf
Borch de Schouboe overtok Lister og Mandal amt fra mai 1815. Broren 42 kristiansands rolle som regionalt styringssentrum hans, Ulrik Frederik Anton de Schouboe, ble amtmann i Nedenes fra
samme tid, men han ble boende i Kristiansand til han sluttet i embetet i
1837. Deretter ser det ut til at embetet har hatt kontor i eller ved Arendal
helt fram til i dag i det nye embetet. I Norge var det fire stift fram til 1800-tallet. Derfor var det fire stiftamt-
menn og fire biskoper i Norge til enhver tid på 1600- og 1700-tallet. Fra
1804 hadde Nord-Norge egen biskop, og i 1863 ble Hamar eget stift igjen,
slik det var før reformasjonen. Biskopen sto over prostene, og prostene over sogneprestene. Embets-
mannen som gikk under tittelen stiftsprost, var prost bare ved dom-
kirka. Han hadde ikke noen overordnet prostefunksjon for hele stiftet. På
1900-tallet ble tittelen endret til domprost.32 Biskopen hadde tilsyn med
prestene og kirkelige tjenere. De skulle ha råd og veiledning av biskopen
i blant annet tros- og samvittighetsspørsmål. Biskopen hadde også flere
andre oppgaver, blant annet å vigsle kirkene. Stiftamtmannen og biskopen hadde mange ansvarsområder innen sine
embeter som de tok seg av hver for seg, og som hver av dem kunne ta opp
direkte med sentralmyndighetene ved behov. Men de hadde også noen
arbeidsfelt der begge hadde ansvaret sammen. I 1672 ble det opprettet en
stiftsdireksjon i hver av stiftsbyene.33 Stiftsdireksjonen besto av stiftamt-
mannen, som var formann, og biskopen. Oppgavene til dette tomanns
kollegiet var blant annet å ha overoppsyn med de såkalte kunjunktime
sakene, det vil si kirkene, kirkegårdene, prestegårdene, hospitalene, skolene
og fattigstellet. Slike oppgaver hadde direksjonen ansvaret for i hele stiftet. Dette framgår også av den nevnte instruksen for stiftamtmannen i 1691. 32
Kiil 1969: 53
33
Kiil 1969: 65 t
p
35
Kongelig reskript 27.04.1742, trykt i: a) Kongelige Rescripter II, s. 326–327; b) Rescripter, Reso
lutioner og Collegial-Breve for Kongeriget Norge i Tidsrummet fra 1660–1813. Til Brug for den
Lovstuderende, udtogsviis udgivne af Julius August S. Schmidt. Første bind, 1660–1784, s. 272–273;
c) Tillæg og Anhang til den af Høiesteretsadvokat Stang og Overretsprocurator Dunker udgivne
Samling af Norge vedkommende Rescripter, Resolutioner og Collegialbreve m.v. for Tidsrummet fra
1660 til 1813. Udgivet af B. Dunker, s. 86. Overøvrigheten i Kristiansand t
Når verdslig og kirkelig ledelse satt sammen i form av tomannskol-
legiet, kunne det by på utfordringer, i hvert fall på 1600- og 1700-tallet. Regelverket sa ikke helt nøyaktig hva kollegiet skulle avgjøre i forhold
til det som stiftamtmannen eller biskopen kunne avgjøre innenfor sine
embeter. Av og til kom det klage til kongen fra stiftamtmann eller biskop
over at den andre avgjorde saker på egen hånd. Biskopen hadde muli-
gens vanskelig for å svelge at stiftamtmannen var den øverste av de to og 43 kapittel 2 skulle være med på å avgjøre kirkespørsmål, mens stiftamtmannen følte
seg oversett hvis biskopen avgjorde mye på egen hånd. I 1742 var stiftamtmann Carl Juell og biskop Jacob Kærup i Kristian
sand uenige om en del spørsmål. Stiftamtmannen sendte et klagebrev til
kongen. Der ble biskopen kritisert for å ha truffet en beslutning angå-
ende et pengeoffer fra menigheten i Kristiansand som to hørere, det vil
si lærere, ved katedralskolen skulle ha. Stiftamtmannen mente at han
selv hadde medbestemmelsesrett i saker som gjaldt kirke og skole, men
at han ikke var blitt konsultert i denne saken, hvor han var uenig i bisko-
pens avgjørelse. De to tolket ikke regelverket for offer på samme måte
i denne saken. I tillegg ble biskopen kritisert for å beholde de originale
reskriptene som kongen sendte til de to, altså til stiftsdireksjonen, mens
stiftamtmannen måtte nøye seg med å få en kopi. Stiftamtmannen opp-
lyste at han likevel hadde «… overbaaret denne biskopens lovstridige og
mig nærgaaende behandling og adfærd, uden derfor ved Sagens videre
drift for høyere Rett, at søge billig Satisfaction».34 Saken ble avgjort ved kongelig reskript til biskopen, som fikk støtte
av kongen. De to hørerne skulle beholde offeret, og reskripter og brev
vedrørende «Geistligheden» skulle oppbevares i biskopens «Stiftskiste»,
altså i bispearkivet.35 Reskriptet var ikke særlig presist på dette punktet,
så direksjonsdokumentene av ymse slag er i dag delvis å finne i bispearki-
vet, delvis i stiftamtmannens arkiv og delvis i et eget stiftsdireksjonsarkiv. Da, som nå, var adgangen til arkivet helt nødvendig for å utføre de opp-
gavene man var satt til. Fikk man ikke adgang og innsyn i arkivet, ble det
lett konflikter, som vi har sett flere eksempler på. Stiftsdireksjonen var i virksomhet i Kristiansand fra 1684, da både
stiftamtmannen og biskopen var på plass i byen. På 1900-tallet var fylkes-
mannen formann i direksjonen. Stiftsdireksjonene ble nedlagt fra 1. 34
SAK, Stiftamtmannen i Kristiansand, Ba, Kopibok 78 (1741–1742), fol. 63a–65b. Brev 16.02.1742. Overøvrigheten i Kristiansand januar
1997 og oppgavene overlatt til bispedømmeråd, biskop og fylkesmann. 44 kristiansands rolle som regionalt styringssentrum 36
Anordning 05.05.1786, trykt i: Kongelige Forordninger II, s. 356–373. Andre regionale organ I tillegg til stiftamtmannens og biskopens virksomheter hadde også
andre typer statlige, regionale instanser basen sin i eller ved Kristian
sand. I noen av dem satt riktignok stiftamtmannen og/eller biskopen
blant representantene. Den ene av disse instansene var domkapitlet. Ved hver domkirke fantes
et domkapittel helt fra middelalderen av. Domkapitlet var et kollegium,
særlig av geistlige, som behandlet kirkelige saker og dømte i ekteskaps
saker og i saker mot geistlige embetsmenn fra hele stiftet. Fra 1600-tallet
ble organet ofte kalt for konsistorialretten. I tillegg til stiftamtmannen og biskopen møtte som regel en prost og
rektoren ved katedralskolen, dessuten en prest, kapellan, predikant eller
medhjelper i menigheten, vanligvis rundt fem personer i alt i konsistorial
retten. Kirkelig jurisdiksjon i ekteskapssaker falt bort fra 1797. I løpet av
1800-tallet falt domkapitlets oppgaver bort, og i 1887 ble all kirkelig juris-
diksjon avviklet. Domkapitlet besto altså ikke av egne ansatte, men av embets- og tje-
nestemenn fra andre offentlige virksomheter. Instansen var i funksjon i
Kristiansand fra slutten av 1684, da både stiftamtmannen og biskopen var
på plass, og i ca. 200 år. I 1786 ble det etablert et offentlig fattigvesen i Kristiansand stift. Det
skulle bestå av lokale fattigkommisjoner. Disse skulle ha en overordnet
instans i stiftet, nemlig en overfattigkommisjon. Den skulle ha sete i
Kristiansand og bestå av stiftamtmannen og biskopen som direktører,
pluss en fra byens magistrat som stiftamtmannen utnevnte, en fra geist-
ligheten som biskopen utpekte, og i tillegg to av de fornemste borgerne
i byen, utpekt av magistraten. Denne overinstansen skulle særlig ta seg
av klagesaker fra stiftet, men også fungere som fattigkommisjon for
Kristiansand by.36 Et annet eksempel på stiftsomfattende organ i tilknytning til fattig-
vesenet, er Kristiansand tukthus. I løpet av 1700-tallet ble det etablert et
tukthus i hver av de fire stiftsbyene. I 1786 ble det bestemt at Kristiansand 45 kapittel 2 skulle etablere en slik anstalt. Det framgår av anordningen om et fattig
vesen i stiftet. Tukthuset ble opprettet i 1789. Opprinnelig var det tenkt
som et arbeids- og manufakturhus for løsgjengere, men ganske raskt ble
det en ren straffeanstalt for kvinner og menn som var dømt for tigging,
tyveri, drap og andre lovbrudd.37 Stiftsdireksjonen hadde den overord-
nede ledelsen av institusjonen, mens en tukthusinspeksjon hadde ansva-
ret for det nærmere tilsynet. 37
SAK, Kristiansand tukthus, 0012a Fangefortegnelse mv. 1776–1860. Fundas 24.07.1789.
38
Kongelig resolusjon 20.04.1876.
39
Helland-Hansen 1952; Wergeland 1963: 183
40
«Statholder Gyldenløves og Jørgen Bjelkes Betænkning angaaende Norges Administration
1670», trykt i Meddelelser fra det norske Rigsarchiv, første bind, s. 404.
41
Samme sted, s. 409. 42
Wergeland 1963: 323–327 Andre regionale organ Tukthuset som institusjon ble nedlagt i 1876.38
Tukthusbygningen, som ble oppført på begynnelsen av 1800-tallet, var en
av byens største bygninger, og ble dermed en svært synlig stiftsinstitusjon. En annen virksomhet var katedralskolen. Kristiansand hadde hatt en
skole før 1680-årene, men som vi har sett ble katedralskolestatusen over-
ført fra Stavanger til Kristiansand fra dette tiåret. Kristiansand katedral-
skole var ikke bare for elever fra Kristiansand by eller stift. Noen få av
elevene, for eksempel i andre halvdel av 1700-tallet, var fra Akershus,
Bergen og Danmark.39 Katedralskolen hadde altså en funksjon for et geo-
grafisk område større enn stiftet. it
En helt annen type virksomhet var det militære. I 1670 vurderte statthol-
der Ulrik Frederik Gyldenløve og generalløytnant Jørgen Bjelke hvilke av
Norges festninger som burde holdes i drift og ved like. Mellom Akershus og
Bergen gjaldt dette ett festningsområde: «Fredriksholm og Christiansand,
formedelst Correspondencen med Danmark, som den nærmeste Plads
imod Judtland, saavelsom og Havnens og Trafiqvens Importants samme-
steds baade for Eders Kongl. Maj.s Flaade saavelsom imod Fremmede.»40
Fredriksholm festning ved Flekkerøy havn ble oppført i 1650-årene. Med
festningsområdet «Christiansand» mentes først og fremst Christiansholm
festning, som sto ferdig i Kristiansand i 1672. De to herrene satte også opp
en oversikt over mannskaper. På Fredriksholm mente de at det skulle være
en kaptein, en løytnant, en sersjant, to korporaler, en tambur, elleve andre
betjenter og 18 menige. Christiansholm skulle ha en oberst, en kaptein, en
sersjant og 12 menige.41 Kristiansand skulle altså ha et mindre mannskap 46 kristiansands rolle som regionalt styringssentrum enn Fredriksholm, men en høyere offiser enn kaptein. Gjennom 1700-tal-
let var kommandantene på Fredriksholm kapteiner og majorer. Komman-
dantene i Kristiansand var oberster og generalmajorer.42 Kristiansand og
Fredriksholm var sentrum for kystforsvaret i hele stiftet. I ufredstider var
det også landmilitære styrker i området. Kristiansand 1662. Kilde: Riksarkivet, DK 3. Kristiansand 1662. Kilde: Riksarkivet, DK 3. Også rettslig sett var Kristiansand et sentralt sted i stiftet før 1900-tal-
let. Fra 1660-årene og gjennom 1700- og 1800-tallet var bygdetinget
første rettsinstans på landet, mens bytinget hadde samme rolle i byen. Fra bygdetinget kunne saker ankes til lagtinget, som var andre instans. Agdesiden lagsogn eller lagdømme besto av nåværende Agder. Lagman-
nens embetssete var Holmegård i Holum, men lagtinget ble holdt rundt
om på forskjellige tingsteder i lagsognet. I byene fantes en mellominstans. 43
Forordning 11.08.1797, trykt i: a) Chronologisk Register, s. 244–253. Tolvte del, 1797–1799; b)
Kongelige Forordninger II, s. 626–631; c) Kongelige Forordninger I, s. 271–275.
44
Lov av 01.07.1887, nr. 5
45
Lov av 31 05 1890 nr 1 43
Forordning 11.08.1797, trykt i: a) Chronologisk Register, s. 244–253. Tolvte del, 1797–1799; b)
Kongelige Forordninger II, s. 626–631; c) Kongelige Forordninger I, s. 271–275. g
g
g
,
3 ; )
g
g
g
,
7
75
44
Lov av 01.07.1887, nr. 5 45
Lov av 31.05.1890, nr. 1 45
Lov av 31.05.1890, nr. 1 Andre regionale organ 47 kapittel 2 Bytingssaker kunne nemlig ankes til vedkommende bys rådstuerett som
andre instans og deretter til lagtinget. Rådstueretten besto av magistraten
og hadde hyppige møter. Lagtingsdommer kunne ankes til Overhoffret-
ten, som trådte sammen på Akershus i januar hvert år. I stiftsbyene kunne
mange dommer ankes direkte fra rådstueretten til Overhoffretten. Derfra
kunne dommer ankes til Høyesterett i København. På slutten av 1700-tallet kom myndighetene fram til at domstolssystemet
var uhensiktsmessig og ikke førte til den ønskede «Forkortelse og Lettelse» i
rettergangen. Saksmengden hadde økt, det var for mange mellominstanser,
og lagtingene holdt rettsmøte bare tre ganger i året. Dermed ble behandlin-
gen av saker tidkrevende og kostbar. I 1797 ble det bestemt at både lagtin-
gene, rådstuerettene og Overhoffretten skulle legges ned ved utgangen av
september. Fra 1. november skulle i stedet en stiftsoverrett være i virksom-
het i hver av de fire stiftshovedstedene som andre instans for både bygde-
ting og byting. Høyesterett skulle fortsatt bestå som tredje instans.43 Kristiansand stiftsoverrett ble dermed etablert i 1797. Dette ble enda et
organ som omfattet hele stiftet, og med sete i Kristiansand. Rettergangen
ble nå mer effektiv både her og i de andre stiftene. Møtene skulle holdes
i rådstuen hver uke. Stiftsoverretten hadde en formann, justitiarius, og
to bisittere, assessorer. Stiftamtmannen hadde også sete i stiftsoverretten. Der skulle han være president og ha oppsyn med orden og verdighet, men
han hadde ingen domsmyndighet. Dermed var det ingen fare for konflikt
mellom stiftamtmannen og de andre om avgjørelser i rettssaker. Fra 1890 ble det omlegginger i domstolsapparatet. Underrettsdommer
skulle ikke lenger ankes inn for stiftsoverrettene, men for nyetablerte
lagmannsretter.44 Agder-fylkene hørte først under Agder lagdømme (lag-
mannsrett), sammen med Telemark og Rogaland, med sete i Kristiansand
1887–1891. Deretter hørte Agder under Borgarting og Agder lagdømme
med sete i Kristiania/Oslo 1892–1936. Fra 1936 har Agder tilhørt Agder
lagdømme med sete i Skien. I 1890 ble det også bestemt at Kristiansand
stiftsoverrett skulle opphøre.45 48 kristiansands rolle som regionalt styringssentrum Ett organ som eksisterte i Kristiansand bare noen få tiår, var stiftamt-
stuen. I 1660-årene ble amtenes regnskaper ivaretatt av amtmennene. Da
stiftamtene ble opprettet, gikk ansvaret for amtsfinansene over til et eget
regnskapskontor, den såkalte stiftamtstuen, i hver stiftsby. Kontoret ble
bestyrt av en stiftamtskriver. I 1680, før Kristiansand ble stiftssentrum,
var stiftamtskriveren den høyeste embetsmannen som bodde i Kristian
sand.46 Kristiansand stiftamtstue fikk ikke lang levetid. Andre regionale organ Den ble lagt ned
i 1713. Stiftamtstueregionen ble da delt, slik at den østlige delen ble lagt til
Kristiania og den vestlige til Bergen.47 Enda en virksomhet var skipsmåling. I 1641 ble det bestemt at alle
skip skulle måles fra da av, slik at skipstollen kunne variere med skipe-
nes drektighet. Ansvaret for skipsmåling lå hos en generalskipsmåler. Under ham fantes en skipsmåler i flere av byene. I 1754 ble det oppret-
tet et embete som generalskipsmåler i hvert stift. Generalskipsmåleren i
Kristiansand hadde også ansvaret for Langesund og Kragerø. Ordningen
varte bare fram til 1794. Fra da av skulle skipsmåling foretas av det lokale
tollvesenet.48 En siste virksomhet som skal nevnes her, er veiarbeid. I 1786 ble det
opprettet et generalveimesterembete for Kristiansand stift, slik som i de
andre stiftene. Men allerede i 1824 ble veimestervesenet i Norge lagt ned,
mens ansvaret for veivesenet ble overført til amtmennene.49 46
Steen 1941: 140
47
Kiil 1969: 193
48
Weidling 2000: 75–76
49
Weidling 2000: 99–100 Endringen i 1919 Gjennom 1800-tallet – etter at Norge i 1814 slapp vekk fra det danske ene-
veldet – kom det opp flere forslag om å endre amtsnavnene her i landet og
ta i bruk gamle, norske landskapsnavn og betegnelser. Dette føyde seg inn
i fornorskingsprosessen og utviklingen av nasjonalfølelsen på den tida. Saken ble ikke mindre aktuell etter unionsoppløsningen i 1905. Torsdag 13. februar 1913 hadde Den norske historiske forening møte for
å diskutere navn på embetsdistriktene. Språkprofessor Marius Hægstad 46
Steen 1941: 140
47
Kiil 1969: 193
48
Weidling 2000: 75–76
49
Weidling 2000: 99–100 49 kapittel 2 holdt foredrag. Han hadde vært medlem av komiteen som ble nedsatt i
1902 for å arbeide med navnesaken. Komiteen leverte en innstilling i 1905. Hægstad sa det var enighet i komiteen om å kalle stiftene for bispedømme. I komiteen gikk Hægstad med på å døpe amt om til syssel. Agder skulle
bestå av «Østagder syssel» og «Vestagder syssel». Men nå – i 1913 – hadde
Hægstad skiftet mening og ville heller bruke fylke. Lederen for HIFO var
professor Halvdan Koht. I møtet var han kritisk til at man skulle ta opp
det oldnorske navnet fylke, som ikke hadde levd på flere hundre år. «Det
blir kunstig som gamle Kluter paa nye Klær», sa han.50 Under navnedebatten som fulgte i Norge i krigsårene 1914–1918 ville
mange gjerne kvitte seg med den tyske betegnelsen amt, og mange gikk
nå inn for å velge fylke, som også var en norsk betegnelse på et admini
strativt område i middelalderen. Blant forslagene til tittel på embetsman-
nen kom det fram jarl, fylkeshøvding og sysselmann, men man endte med
fylkesmann. Ved lov av 14. august 1918 ble amt forandret til fylke. De to amts
navnene på Agder ble forandret til Aust-Agder fylke og Vest-Agder fylke. Tittelen stiftamtmann falt bort. På det tidspunktet var det likevel ikke
noe særlig igjen av stiftamtmannens opprinnelige særoppgaver. Samtidig
ble stift endret til bispedømme, og Kristiansand stift skulle nå hete Agder
bispedømme. Endringene skulle tre i kraft fra 1. januar 1919. Stavanger
bispedømme ble for øvrig opprettet, eller gjenopprettet, i 1924, gjeldende
fra 1925.51 Fra 1. januar 2005 endret Agder bispedømme navn til Agder og
Telemark bispedømme. Fra 1925 hadde biskopen med sete i Kristiansand ikke lenger Rogaland
i embetsdistriktet sitt. For så vidt kan man si at Kristiansands rolle som
regionalt styringssentrum var svekket, i hvert fall geografisk i kirkelige
saker. 50
Flekkefjords-Posten 18.02.1913
51
Lov av 11.08.1924 53
Statsarkivet i Kristiansand / Arkivportalen, arkivkatalog for Elektrisitetstilsynet 3. distrikt. Endringen i 1919 Den største forskjellen kom til å gjelde i verdslig henseende. Fra 1919
hadde Kristiansand ikke noen stiftamtmann. Hvert fylke fikk i stedet sin
fylkesmann, med et departement som sin overordnede. Kristiansands
stilling som regionalt styringssentrum ble dermed svekket på 1900-tallet 50 kristiansands rolle som regionalt styringssentrum med hensyn til det gamle systemet, der stiftamtmannen var regionens
høvding, oppsynsmann og bindeledd mellom sentral- og lokalmyndig-
hetene i verdslige spørsmål, uansett fag. Dette gjaldt riktignok også de
andre stiftamtene. Fra tiårene rundt 1900 vokste det fram ulike statlige fagetater med
regional inndeling, med egne etatssjefer og med hyppige endringer med
hensyn til organisasjon, geografisk virkeområde, administrasjonssete og
navn. Vi skal bare kort nevne ett eksempel her. I 1897 ble det etablert
et statlig tilsyn med elektriske anlegg.52 Landet ble delt i fem tilsyns
distrikter, der 3. distrikt omfattet Agder og Rogaland. Telemark ble fra
1912 overført fra 2. distrikt til 3. distrikt. Rogaland ble overført til 4. dis-
trikt fra 1924, men store deler av fylket ble fra henholdsvis 1931 og 1937
tilbakeført til 3. distrikt. Tilsynsmannen for 3. distrikt hadde tilhold i
Arendal 1898–1957, og deretter i Kristiansand.53 1900-tallet innebærer
et helt annet kapittel for den sørligste regionen i Norge og faller utenfor
oppgaven å gjøre rede for her. 52
Kongelig resolusjon 27.11.1897 52
Kongelig resolusjon 27.11.1897 Konklusjon Agder har vært en del av mange ulike typer stiftsomfattende organ i peri-
oden 1600-tallet til rundt 1900. Omtrent halvparten av virksomhetene
som vi har sett på, eksisterte med visse endringer i omtrent hele perioden,
nemlig stiftamtet, stiftet, stiftsdireksjonen, katedralskolen, domkapitlet
og kystforsvaret. Når de har eksistert såpass lenge uten større organisa-
toriske endringer, må det tas som tegn på at de har fungert etter sin hen-
sikt i den lange perioden. De andre har eksistert i noen få eller mange
tiår i perioden. Stiftamtstuen er den eneste som eksisterte fra slutten av
1600-tallet og bare fram til begynnelsen av 1700-tallet. Overfattigkom-
misjonen, tukthuset og stiftsoverretten eksisterte så å si fra slutten av
1700-tallet og ut 1800-tallet. En skipsmålingsansvarlig for stiftet fantes
bare i andre halvdel av 1700-tallet, og en generalveimester for stiftet var i
virksomhet bare noen få tiår rundt 1800. 51 kapittel 2 kapittel 2 Det var Kristiansand som ble sete for ledelsen av alle de nevnte instan-
sene, og byen hadde dermed en klar rolle som verdslig, geistlig, rettslig
og militært styringssentrum for stiftsregionen. Den første mannsalderen
etter 1641 var byen ung og trolig for liten til å fylle rollen. Men da for-
svarsverkene ble utbygd i og rundt Kristiansand fram mot 1680-årene,
ble byen rikets hovedfestning mellom Akershus og Bergen. Flekkerøy var
fra gammelt av en stor og viktig flåtehavn. Kristiansand hadde nærhet
til Danmark, og utgjorde en slags portstolpe i sjøveien mellom Vest- og
Øst-Europa. Den strategiske posisjonen var utvilsomt bakgrunnen for at
kongen ville satse på Kristiansand som administrasjonssentrum i regio
nen i stedet for Stavanger. Ladestedet Arendal, som fikk rettigheter som
kjøpstad i 1723, hadde ikke den strategiske betydningen som Kristian
sand, og var derfor ikke et alternativ som hovedstad i regionen. Embetsmennene som hadde det regionale setet sitt i Kristiansand,
utgjorde ikke mange personer, og særlig to av dem opptrådte i ledelsen
av flere av organene. Stiftamtmannen var leder av stiftamtet og biskopen
av stiftet. Begge utgjorde stiftsdireksjonen alene, og begge utgjorde den
overordnede ledelsen av overfattigkommisjonen og tukthuset, og begge
satt i domkapitlet sammen med tre andre. Stiftamtmannen var president
i stiftsoverretten, men det var tre dommere som dømte. Flere av med-
lemmene i domkapitlet og overfattigkommisjonen og tukthustilsynet var
lokale embets- og tjenestemenn med andre hovedyrker. Stiftamtmannen og biskopen var de to med klart høyest status i hele
perioden. Dernest kom nok rektor ved katedralskolen. Offiserene hadde
også høy status. Det samme gjaldt for dommerne i stiftsoverretten fra
slutten av 1700-tallet. Hele perioden sett under ett var det altså ikke snakk om særlig mange
personer. Hvis man derimot tar for seg alle embets- og tjenestemenn som
hadde virket sitt i Kristiansand, men som ikke hadde noen roller i stifts-
omfattende organ, dreide det seg utvilsomt om flere titalls personer. Blant
dem var byfogden, by- og rådstueskriveren, politimesteren, tollerne,
losene og forlikskommissærene, for å ta noen eksempler. Stiftsbyen hadde små stiftsorgan med få ansatte, men med et stort
geografisk virkeområde. Tilstedeværelsen av de nevnte stiftsomfattende 52 kristiansands rolle som regionalt styringssentrum organene markerte at Kristiansand var hovedstaden i stiftet og en av de
fire hovedbyene i Norge. Spørsmålet om hvordan de forskjellige organene kom til å fungere i
praksis med hensyn til blant annet organisering, oppgaver og utfordrin-
ger, krever videre forskning. kapittel 2 Kildetilfanget er rikt nok til å finne ut mye
om det innenfor flere av organene. Kilder Chronologisk Register = Chronologisk Register over de Kongelige Forordninger og
Aabne Breve, samt andre trykte Anordninger, som fra Aar 1670 af ere udkomne,
tilligemed et nøiagtigt Udtog af de endnu gjeldende, for saavidt samme i
Almindelighed angaae Undersaatterne i Danmark og Norge, forsynet med et
alphabetisk Register ved Assessor Jacob Henric Schou. Tolvte del, 1797–1799. Kiøbenhavn: N. Christensen, 1800. Flekkefjords-Posten 18.02.1913. Flekkefjords-Posten 18.02.1913. Kongelige Forordninger I = Kongelige Forordninger, aabne Breve og andre trykte
Anordninger for Norge. Udkomne i Tidsrommet 1648–1814. Udgivne i Udtog af
Fr. Timme. Andre del, 1771–1814. Christiania: Forlagt av J.W. Cappelen, «Trykt i
det Wulfbergske Bogtrykkeri», 1842. Kongelige Forordninger I = Kongelige Forordninger, aabne Breve og andre trykte
Anordninger for Norge. Udkomne i Tidsrommet 1648–1814. Udgivne i Udtog af
Fr. Timme. Andre del, 1771–1814. Christiania: Forlagt av J.W. Cappelen, «Trykt i
det Wulfbergske Bogtrykkeri», 1842. Kongelige Forordninger II = Kongelige Forordninger og aabne Breve samt andre trykte
Anordninger m.m. som fra Aar 1670 til 1814 ere udkomne og vedkomme Kongeriget
Norges Lovgivning i tidsfølgende Orden og udtogsviis udgivne og forsynede med
alphabetisk Register af Peter Hersleb Smith. Andre del, 1755–1800. Christiania:
«Trykt i det Wulfbergske Bogtrykkerie af R. Hviid» 1824. Kongelige Forordninger II = Kongelige Forordninger og aabne Breve samt andre trykte
Anordninger m.m. som fra Aar 1670 til 1814 ere udkomne og vedkomme Kongeriget
Norges Lovgivning i tidsfølgende Orden og udtogsviis udgivne og forsynede med
alphabetisk Register af Peter Hersleb Smith. Andre del, 1755–1800. Christiania:
«Trykt i det Wulfbergske Bogtrykkerie af R. Hviid» 1824. Kongelige Rescripter I = Kongelige Rescripter, Resolutioner og Collegialbreve for
Danmark og Norge, udtogsviis udgivne i chronologisk Orden ved Laurids Fogtman. Andre del, 1670–1699. Kiøbenhavn: Gyldendals Forlag, 1803. Kongelige Rescripter II = Kongelige Rescripter, Resolutioner og Collegialbreve for
Danmark og Norge, udtogsviis udgivne i chronologisk Orden ved Laurids Fogtman. Fjerde del, andre bind, 1740–1746. Kiøbenhavn: Gyldendals Forlag, 1788. Kongelige Rescripter III = Kongelige Rescripter, Resolutioner og Collegial-Breve for
Norge i Tidsrummet 1660–1813. Udgivne i Udtog af Fr. Aug. Wessel Berg. Første bind,
1660–1746. Christiania: Forlagt av J.W. Cappelen. Trykt i P.T. Mallings Officin. 1841. Norske Rigs-Registranter, bd. 6, 1628–1634. Christiania: A.W. Brøgger, 1877. Riksarkivet, Danske Kanselli, Fcab, 0012 Norske tegnelser 1670–1683. Riksarkivet, Danske Kanselli, Fcca, 0035 Norske innlegg 1682–1683. Kongelige Rescripter III = Kongelige Rescripter, Resolutioner og Collegial-Breve for
Norge i Tidsrummet 1660–1813. Udgivne i Udtog af Fr. Aug. Wessel Berg. Første bind,
1660–1746. Christiania: Forlagt av J.W. Cappelen. Kilder Trykt i P.T. Mallings Officin. 1841. Norske Rigs-Registranter, bd. 6, 1628–1634. Christiania: A.W. Brøgger, 1877. Riksarkivet, Danske Kanselli, Fcab, 0012 Norske tegnelser 1670–1683. Riksarkivet, Danske Kanselli, Fcca, 0035 Norske innlegg 1682–1683. Riksarkivet, Danske Kanselli, Fcca, 0035 Norske innlegg 1682–1683. 53 kapittel 2 Riksarkivet, Danske Kanselli, Fcca, 0040 Norske innlegg 1686–1687. Riksarkivet, Danske Kanselli, Skapsaker, F, 0066 Skap 14, pakke 324–333, 1623–1686. Rescripter, Resolutioner og Collegial-Breve for Kongeriget Norge i Tidsrummet fra
1660–1813. Til Brug for den Lovstuderende, udtogsviis udgivne af Julius August S. Schmidt. Første bind, 1660–1784. Christiania: Chr. Tønsbergs Forlag, 1847. Samling af Norge vedkommende Kgl. Rescripter, Resolutioner og Collegialbreve m.v. for Tidsrummet fra 1660 til 1813, forsaavidt de kunne ansees at være af Vigtighed
for den Lovstuderende og den juridiske Embedsmand i Almindelighed. Udtogsviis
udgiven af F. Stang, B. Dunker. Christiania: Forlagt av Johan Dahl, 1838. «Statholder Gyldenløves og Jørgen Bjelkes Betænkning angaaende Norges
Administration 1670», trykt i Meddelelser fra det norske Rigsarchiv, første bind. Christiania: Feilberg & Landmarks Forlag, 1870. Tillæg og Anhang til den af Høiesteretsadvokat Stang og Overretsprocurator Dunker
udgivne Samling af Norge vedkommende Rescripter, Resolutioner og Collegialbreve
m.v. for Tidsrummet fra 1660 til 1813. Udgivet af B. Dunker. Christiania: Forlagt av
Johan Dahl, 1840. Aarsberetninger fra Det Kongelige Geheimearchiv, indeholdende Bidrag til dansk Aarsberetninger fra Det Kongelige Geheimearchiv, indeholdende Bidrag til dansk
Historie af utrykte Kilder. Udgivne af C.F. Wegener. Andre bind. København:
I kommisjon hos C.A. Reitzel, 1856–1860. Aarsberetninger fra Det Kongelige Geheimearchiv, indeholdende Bidrag til dansk
Historie af utrykte Kilder. Udgivne af C.F. Wegener. Andre bind. København:
I kommisjon hos C.A. Reitzel, 1856–1860. Historie af utrykte Kilder. Udgivne af C.F. Wegener. Andre bind. København: 1
Bakgrunnsmaterialet for kapitlet er i hovudsak henta frå Leonhard Jansen et al. (2019) Frå post-
veg til riksveg – vegar og vegminne langs riksveg 9. Litteratur Finne-Grønn, S. H. (1932). Norges Prokuratorer, Sakførere og Advokater 1660–1905: Finne-Grønn, S. H. (1932). Norges Prokuratorer, Sakførere og Advokater 1660–1905: Finne-Grønn, S. H. (1932). Norges Prokuratorer, Sakførere og Advokater 1660–1905: Bd. 1. Den norske sakførerforening. Friis, J. (1941). Stiftamtmenn i Kristiansand før 1814. Fædrelandsvennens trykkeri. Helland-Hansen, K. (1952). Elevprotokoll for Kristiansands Katedralskole 1756–1860. Bd. 1. Den norske sakførerforening. Friis, J. (1941). Stiftamtmenn i Kristiansand før 1814. Fædrelandsvennens trykkeri. Helland-Hansen, K. (1952). Elevprotokoll for Kristiansands Katedralskole 1756–1860. Trykt og innbundet hos Edgar Høgfeldt AS. Kiil, A. (1969). Arkivkunnskap. Statsarkiva. Universitetsforlaget. Trykt og innbundet hos Edgar Høgfeldt AS. Kiil, A. (1969). Arkivkunnskap. Statsarkiva. Universitetsforlaget. Leewy, K. (1956). Kristiansands bebyggelse og befolkning i eldre tider. Christianssands
Sparebanks Historiefond. Leewy, K. (1956). Kristiansands bebyggelse og befolkning i eldre tider. Christianssands
Sparebanks Historiefond. Mykland, K. (1977). Norges historie: Bd. 7. Gjennom nødsår og krig 1648–1720. J. W. Cappelens forlag AS. Mykland, K. (1977). Norges historie: Bd. 7. Gjennom nødsår og krig 1648–1720. J. W. Cappelens forlag AS. Mykland, K. (Red.). (1980). Norges historie: Bd. 15. Historisk atlas, oversikter, register. J.W. Cappelens forlag AS. Mykland, K. (Red.). (1980). Norges historie: Bd. 15. Historisk atlas, oversikter, register. J.W. Cappelens forlag AS. Steen, S. (1941). Kristiansands historie 1641–1814. Grøndahl & Søn. Tronstad, R. (2008). «Henrik Wergelands tilknytning til Kristiansand», i
Wergelandfamilien og Kristiansand. Årbok 2008. Vest-Agder-museet. Weidling, T. (2000). Eneveldets menn i Norge. Sivile sentralorganer og embetsmenn
( k ft
)
k
k Tronstad, R. (2008). «Henrik Wergelands tilknytning til Kristiansand», i
Wergelandfamilien og Kristiansand. Årbok 2008. Vest-Agder-museet. Weidling, T. (2000). Eneveldets menn i Norge. Sivile sentralorganer og embetsmenn
66
8
(Sk ift
i
) Rik
ki Weidling, T. (2000). Eneveldets menn i Norge. Sivile sentralorganer og embetsmenn 1660–1814 (Skriftserie 7). Riksarkivaren. Wergeland, N. (1963). Christiansands Beskrivelse. Universitetsforlaget. 54 kapittel 3 Sitering av dette kapitlet: Jansen, L. (2020). På tvers eller på langs? Setesdølane sin kontakt med verda
ikring seg? I Johnsen, B.E. og Vadum, K. (red.), Grenseløst Agder. Det som skilte og det som bandt
(s. 55–74). Oslo: Cappelen Damm Akademisk. https://doi.org/10.23865/noasp.111
Lisens: CC BY-NC-ND. På tvers eller på langs?
Setesdølane sin kontakt
med verda ikring seg Leonhard Jansen Setesdal er av mange kjend som den lukka dalen der tida har stått stille i
bygder der folk stort sett hadde nok med seg sjølve, og brydde seg lite om
kva som rørde seg andre stader. Slik var det ikkje. Også setesdølane måtte
ut i den vide verda. Men vegvalet vart ofte påverka av tilhøve utanfor
dalen. Handel var viktig, ikkje minst fordi dei ikkje makta å produsere
tilstrekkeleg med kornvarer til livsopphaldet. Offentlege ærend førde dei
til byar og bygder der styresmaktene oppheldt seg. Endringar i nærings-
grunnlag, administrativ organisering, og frå 1840-åra også bygging av
postveg, var på mange vis styrande for kvar setesdølane la vegen.1 I boka si Ferd og fest frå 1929 skriv Sverre Steen: I boka si Ferd og fest frå 1929 skriv Sverre Steen: l det almene folks bevissthet lever sikkert en bestemt forestilling om at Setes-
dalen, Norges svarteste avdal, har ligget utenfor Norge liksom visse andre
deler i vårt vidstrakte land. Vi kjenner alle derfra noen merkelige drakter
som vi har sett på museum, korte, vide stakker med bånd, lang-brok med 1
Bakgrunnsmaterialet for kapitlet er i hovudsak henta frå Leonhard Jansen et al. (2019) Frå post-
veg til riksveg – vegar og vegminne langs riksveg 9. 55 kapittel 3 skinnbak, tollekniv og pannelokk, «spir». Vi kjenner gammeldags treskurd
og rosemalte ølboller, som forresten ikke er gamle. Vi har hørt en del dunkle
historier om Onde-Asmund, eventyrkjempen fra Rygnestad, og presten som
ble stukket ihjel av bønder som var øre av brennevin og hjemmebrygg som
skulle være uhorvelig sterkt. Og vi danner oss et bilde av Setesdal som noe
henimot mørkeloft, med underlige forglemte saker, mugg og støv og glinsende
villdyrøine og ram lukt. Og så sukker vi et kultivert sukk: Ja, slik går det når
man holder sig borte fra samkvem med andre folk, når man er sig selv nok. Nu
er det heldigvis bedre: jernbane og bilrute og melkekjøring og civilisasjon og
samferdsel og smugling og lykke i Setesdalen også. Men vi har nok dømt feil
igjen, og innbilt oss at fortids folk var like låke til bens og like gjerrige på tiden
som vi tror vi er. Vi har glemt at kjøreveier var helt unødvendige for folk som
skulle ride. Vi har igjen glemt at avsidesliggende slett ikke betyr avstengt.2 Sverre Steen var ikkje den første som gjorde seg sine tankar om setesdølen
og det eksotiske. Oppfatninga av Setesdal som noko for seg sjølv, lengst
inn i Råbyggjelaget, isolert og eksotisk, er gamal. Sokneprest i Valle, Reier
Gjellebøl, var ein av dei fyrste som gav næring til denne måten å tenke på
då han i 1777 skreiv sin Beskrivelse over Sætersdalen: Omendskjønt dette Folk er et fattigt Folk, og tidt lider mangel paa adskil-
lige Ting, saa er dog den Kjærlighed til deres Fødested saa stor, at de heller
udvælge at lide ondt hos deres egne, end at have det godt hos Fremmede. 2
Steen 1929: 238
3
Gjellebøl 1800: 15 2
Steen 1929: 238 I boka si Ferd og fest frå 1929 skriv Sverre Steen: […]
Jeg vil ikke anføre flere Beviser herpaa, end dette at man sjelden, ja aldrig
her hører at nogen tager Tjeneste i nogen By eller giver sig sammesteds til
nogen Profession, meget mindre lader sig hverve til Garnisons Tjeneste uden
Commando.3 Det som er eit lite paradoks i denne samanheng er at det Gjellebøl i si sam-
tid observerte truleg er ganske korrekt. På 1700-talet og tidleg 1800-tal
var det svært få som reiste frå dalen, og svært få som flytta inn. Når folk
flytta var det til ei anna bygd i dalen. Kanskje ikkje så mykje merkande 56 på tvers eller på langs? frå år til år, men i statistisk form kan det registrerast som ei gliderørsle
nedover dalen mot kysten. På 15- og 1600-talet hadde det vore stor trafikk, så vel mellom dalføra
som langsetter. Truleg hadde dette å gjere med at det på 1700-talet utvikla
seg eit omfattande husmannsvesen som absorberte dei fleste, men som på
grunn av sterk folkevekst nådde eit mettingspunkt to-tre tiår ut på 1800-
talet. Då Postvegen kom i 1840-åra var det mest som å opne ein ventil. Samstundes begynte dølar i hundretal å emigrere til Amerika.4 Sjølv om vi har liten detaljkunnskap om reiser før kjeldematerialet tek
til å flyte rikare utover på 1600-talet, kan vi utifrå den kunnskap vi har
setje opp nokre sannsynlege grunnar for at dei likevel ganske ofte måtte
take seg ein tur utanbygds: • dei var avhengige av å kjøpe mat (korn, salt, m.m.) • dei var avhengige av å kjøpe mat (korn, salt, m.m.) • i vanskelege år og i periodar med folkevekst måtte nokon søke ut for
å sikre seg eit næringsgrunnlag • offentlege ærend (kyrkje, rettsstell, administrasjon, soldatteneste) Ei følgje av slike ferder kunne vere giftarmål og meir kontakt. Ei følgje av slike ferder kunne vere giftarmål og meir kontakt. Det vi alt no kan slå fast, er at dølane sine reiseruter og vegval har vore
i endring så langt tilbake vi har grunnlag for å meine noko. 5
Jansen & Ryningen 1994, bd. VII: 21ff 4
Jansen & Ryningen 1994, bd. VII: 280–288f 4
Jansen & Ryningen 1994, bd. VII: 280–288
5
Jansen & Ryningen 1994, bd. VII: 21ff Dei eldste vegane Arkeologiske funn viser at dei fyrste jegerane kom til Setesdal i eldre
steinalder (8000–6500 f. Kr.). Det er rimeleg å tru at dei kom vestfrå, men
vi veit det sjølvsagt ikkje. Det skulle gå endå 2–3000 år før dei begynte
å halde husdyr og dyrke jorda, og eit samanhangande jordbruk er enda
yngre.5 Vi må likevel skyte inn at under dei arkeologiske utgravingane på
Langeid i Bygland i 2011 vart det funne stolpehol med restar av kol som
er daterte til eldre steinalder. Det kan tolkast slik at det då var nokon som 57 kapittel 3 hadde bygt seg hus på Langeid og budde der. Førebels har vi lite å saman-
halde desse dateringane med, men det er eit indisium på at busetjinga i
Setesdal er eldre enn vi tidlegare har hatt grunnlag for å meine.6 Våre auge ser etter den kortaste vegen, medan dei den gong såg etter
det som var mest praktisk og hensiktsmessig. Reisa hadde også ei mei-
ning i den forstand at dei mest alltid frakta med seg eit eller anna. Vi må også hugse på at dei valde ulike vegliner ettersom vêret var,
om det var sommar eller vinter, om bekkane og elvene fløymde eller var
turre, om dei hadde hest og kløv eller bar på ryggen osb. Overordna prin-
sipp var å leggje vegen der det var lett å gå. Vegane følgde terrenget. «Dei
gamle gjorde heiane flate», heiter det i Setesdal. Frå Valle og nordover var lenge Stavanger den viktigaste byen. I løpet
av ein dag eller to kunne byklarar og valldølar kome seg til sjøen (Ryfylke,
Lysefjorden), setje frå seg hestane der og ordne båtskyss. For byklarane kunne ei reise til Kristiansand vare i opptil tre veker. Sjølv med båttransport for varene på Byglandsfjorden, måtte hestar og
sledar følgje etter heile vegen til byen slik at ein fekk frakta varene med seg
over land der det ikkje var framkomeleg med båt. Det var ei slitsam reise.7 I godt vêr orienterte dei seg ved hjelp av fjell og landskap. Når uvêr med
regn og skodde reduserte sikten til eit minimum, måtte dei take andre
hjelpemiddel i bruk. Nokre stader var det «nyddingar»; steinar som var
lagde oppå kvarandre for å markere vegen. Det var også vanleg å byg-
gje vardar som var store og synlege på lang avstand. Nokre av desse er
gluggevardar, dvs. 6
Wenn 2016: 4
7
Jansen & Ryningen 1994, bd. VII: 46ff 6
Wenn 2016: 4 Dei eldste vegane det går eit hol gjennom varden som dei kunne sjå gjen-
nom og take retninga med. Der ferdsla var stor vart terrenget nedslite, og det gjorde vegen lett å
sjå. Desse vegane er framleis i bruk av folk som ferdast i fjellet, og ikkje
minst av dei mange sauene som kvart år går der på sommarbeite. Men korleis reiste så setesdølane? Eg vel i denne samanheng å defi-
nere Setesdal som området frå grensa mot Telemark til Byglandsfjord. Lenger sør budde «blåmennene», landskapet var opnare der, og kontak-
ten med kysten tettare. Det spegla seg att mellom anna i byggjeskikk og 58 på tvers eller på langs? klededrakt. Nemninga «blåmenn» siktar til at dei ikkje brukte setesdals-
drakt, men dressa seg i bukser og jakke laga av blåsvart ulltøy. I dag går rv. 9 langsetter Byglandsfjorden. Før Postvegen kom i 1844 gjekk turen oppe
på heia frå Senum ved Byglandsfjord til Ose. Det var enklare enn å ta seg fram i dal-
botnen. Kart frå boka «Frå postveg til riksveg», utarbeidd av Harald Tallaksen. I dag går rv. 9 langsetter Byglandsfjorden. Før Postvegen kom i 1844 gjekk turen oppe
på heia frå Senum ved Byglandsfjord til Ose. Det var enklare enn å ta seg fram i dal-
botnen. Kart frå boka «Frå postveg til riksveg», utarbeidd av Harald Tallaksen. Langs dalføret gjekk det vegar – relativt korte vegstubbar – mellom gardane
og mellom grendene. Ikkje nødvendigvis opparbeidd veg, men slik at det
var mogeleg å take seg fram. Fleire stader stuper fjellsida like ned i elva eller
fjorden, og det er uråd å kome forbi utan båt. I prinsippet kunne ein med
å bruke ein kombinasjon av småvegar, omvegar, robåtar og ferjer take seg
fram i dalbotnen heilt ned til Kristiansand. I praksis var dette tungvint. Spe-
sielt når vi har i minnet at dei også skulle ha hest og lass med på same turen. Langs dalføret gjekk det vegar – relativt korte vegstubbar – mellom gardane
og mellom grendene. Ikkje nødvendigvis opparbeidd veg, men slik at det
var mogeleg å take seg fram. Fleire stader stuper fjellsida like ned i elva eller
fjorden, og det er uråd å kome forbi utan båt. I prinsippet kunne ein med
å bruke ein kombinasjon av småvegar, omvegar, robåtar og ferjer take seg
fram i dalbotnen heilt ned til Kristiansand. I praksis var dette tungvint. kapittel 3 kapittel 3 Den vanlegaste reiseruta for dei som ferdast etter dalen var å bruke
heia. For eksempel gjorde dei det på vestsida av Byglandsfjorden, ved
Senum, og kom ned i dalen att ved Ose. Ein annan stad var mellom Valle og Bykle. Det var uråd å kome forbi
den berykta Byklestigen så vel med slede som med tung kløv. Då la dei
i veg over heia over mot Bjørnevatn, og vidare til Stavenes i Bykle for til
sist å finne ein plass å krysse elva, gjerne nord for sjølve Bykle kyrkjebygd. Dernest gjekk det mange vegar på tvers av heiane. Mest kjend er utan
tvil Skinnevegen frå øvre del av Setesdal over til Lysefjorden. Stavanger
vart etablert som bispesete i 1125, og skatten til biskopen vart levert i form
av skinn. Vi finn det mellom anna att i det gamle takstsystemet på jordei-
gedomar, som frå 1600-talet vart målt i huder og skinn. Den tid vart nok
også skatten betalt på andre måtar, men namnet Skinnevegen levde vidare.8 Men folk ferdast nok her før den tid au. Transporten var tung og vans
keleg, og dei kunne berre frakte med seg konserverte varer som huder,
talg, smør og tørka kjøtt. Vi må likevel ikkje gløyme at det var grenser for
kor mykje av denne type vare ein kunne tillate seg å selje frå ein dal som
knapt nokon gong har vore heilt sjølvforsynt med mat. Austover frå Valle gjekk Bispevegen over til Fyresdal. Historikaren P. A. Munch meinte at Bispevegen var ein av tri «principale Fjældveie» i
Sør-Noreg. Eit knutepunkt for ferdsla vestover frå Austlandet var Moland
i Fyresdal. Derfrå gjekk Bispevegen over heia til Valle.9 I tillegg til desse hovudlinene var det sjølvsagt mange andre veger som
gjekk over heia. Dei fleste starta på garden der bonden budde. Det vil føre
for langt å gå inn på alle her. 8
Jansen 2018: 27f
9
Dybdahl 1947: 45
10
Orknøyingasoga 1929: 114–124 9
Dybdahl 1947: 45 Dei eldste vegane Spe-
sielt når vi har i minnet at dei også skulle ha hest og lass med på same turen. Vintervegane på isen var lette å ferdast etter, men det var usikre vegar
som bokstaveleg talt kunne forsvinne under føtene. Vår og haust var det
ofte lange periodar at fjorden ikkje var farbar på noko som helst vis. 59 Korleis reiste folk? Og kvar reiste dei? Vi har lite handfast å vise til for å dokumentere korleis setesdølane tok
seg fram og kvar dei reiste i den eldste tida. Med unntak av ei reise frå
Gulen i Sogn til Valle, og derfrå til Bringsvær i Fjære kring år 1128,10 må 60 på tvers eller på langs? vi heilt fram til 1500-talet før dei første kjeldene begynner å nemne slikt. Og då er det gjerne som halvkvedne viser; f.eks. vert Vonde-Åsmund
Rygnestad kalla «en lands floge» som kan oppfattast slik at han vore i
utlandet. Eigedomshandlar er andre vitnemål som indirekte fortel at
nokon har vore på reis.11 Ut over det er det indikasjonar på at det i vikingtid og middelalder
kan ha vore fleire marknadar også i Setesdal, der utanbygds handels-
menn kom med varene sine. Produksjon av jern gav utan tvil grunnlag
for omfattande handel. Uvanleg mange arkeologiske funn av vekter og
vektlodd, som nødvendigvis må ha ein samanheng med kjøp og sal, stør
ei slik hypotese. Meir vanleg enn dei fleste andre stader på Agder, finn vi
importerte varer i gravene: våpen, mynter, glas og smykke. For førti år sidan la arkeologen Jan Henning Larsen, på bakgrunn av
desse funna, fram ein teori om at det kan ha vore ein stor marknadsplass i
Valle i vikingtida.12 Dette vart endå meir styrkt gjennom utgravingane på
Langeid. Funnet kan eintydig daterast til rett etter år 1000, og ei øks som
vart funnen i ei av gravene knyter den gravlagde til Knut den mektige sitt
felttog i England 1015–16. At det var setesdølar med i det felttoget veit vi
mellom anna frå innskrifta på galtelandsteinen på Evje, der det står (på
moderne norsk): Arnstein reiste denne steinen til minne om Bjor, son sin;
han døydde i hæren då Knut angreip England. Ein er Gud.13 Sverdet som vart funne i den eine grava er eitt av dei mest praktfulle vi
kjenner frå norsk jernalder. Fragment av arabiske og europeiske myntar
er også noko vi merker oss.14 Importgjenstandane er udiskutable bevis på kontakt mellom Setes-
dal og andre område. Kvar møteplassane har vore, der setesdølane sine
varer vart bytta i varer og myntar av gull og sølv, er ukjent. Men logikken
tilseier at det må ha vore på marknadsplassar i landsdelen, og også direkte
med båtar som kom inn i fjordane langs kysten. 11
Ryningen 1987: 349
12
Larsen 1980
13
Larsen 2013: 63
14
Wenn 2016: 205f Korleis reiste folk? Og kvar reiste dei? Vi veit at det føregjekk ein stor produksjon av jern med utgangspunkt
i myrmalm frå vikingtida til eit stykke ut i seinmiddelalderen. Det er 11
Ryningen 1987: 349
12
Larsen 1980
13
Larsen 2013: 63
14
Wenn 2016: 205f 61 kapittel 3 vanleg å rekne at ein vanleg gard på den tid hadde eit behov på ein kilo
jern årleg. Berre i Bykle kan produksjonen ha vore opp mot 20 tonn årleg
utifrå nyare vurderingar. Det vart utan tvil produsert jern for heile Agder
og Rogaland. I tillegg må det ha vore ein betydeleg eksport til utlandet.15 Det kontaktnettet og den handelen desse funna vitnar om, viser at det
må ha vore eit nettverk av vegar med ei viss form for organisering. Desse
har gått langsetter dalen, men også vestover (Skinnevegen) og austover
(Bispevegen). Dess lenger opp i dalen, dess kortare var vegen til sjøen og
Vestlandet, og mogelegheiter for båtfrakt. Det er grunn til å tru at Setes-
dal på denne tida var del av eit velorganisert handelsnettverk der jern
var ei viktig salsvare. Ikkje berre til områda nærare kysten, men også
til eksport. Det må ha vore ei betydeleg ferdsle mellom marknadane og
produksjonsstadene for jern. Funna på Langeid er i denne samanheng verdt å merke seg. I dag er det
ei grend med ikkje så svært mange fastbuande, og difor tykkjest det ufor-
ståeleg at den rikdomen som er avdekka under arkeologiske utgravingar
er å finne akkurat der. Ei hypotese vil vere at ein på Langeid kan setje ein båt på vatnet og ro
eller segle like ned til Byglandsfjord. Der måtte ein på land, men så var
det mogeleg å bruke båt att frå Fennefoss til enden av Kilefjorden. Då er
det og sannsynleg at einkvan på Langeid hadde ein viss kontroll med
handelen med jern, og hadde kontakt med dei som skulle ha vara og som
hadde båtar til å frakte med. Om dette kan vere rett tenkt, er det likevel
ingen haldepunkt for korleis dette kan ha vorte praktisert. I historisk tid vart fraktebåtane på Byglandsfjorden kalla senumsbåtar
etter garden Senum like vest for sjølve Byglandsfjord. Med utgangspunkt
i gamle foto som vi meiner kan vise senumsbåtar, var dei ganske store. 15
Mjærum & Larsen 2013
16
Skar 1961: 134
17
Jansen & Ryningen 1994, bd. VIII: 291f Korleis reiste folk? Og kvar reiste dei? I Gamalt or Sætesdal vert det sagt at senumsbåtane «bar seksti klyvjer
um lag; ein eller tvo mann rodde, og so laga dei til ‘tjellsegl’ dei hadde på
båten».16 Dei må ha vore svært viktige for transport av tyngre varer som
ikkje utan vidare kunne kløvjast på hesteryggen, og når store volum –
som til dømes kornvarer – skulle fraktast til gards.17 62 på tvers eller på langs? Nye ordningar på 1500- og 1600-talet Svartedauden resulterte i store endringar i det norske samfunnet. For det
første gjekk den organiseringa som hadde vore meir eller mindre i opp-
løysing, og det skulle ta lang tid før det kom ei funksjonell erstatning. På 1500-talet skyt gardsdelinga fart og folketalet aukar. Fram mot 1650
har setesdølane eigedomar både i Telemark, Sirdal, Tovdal, Gjøvdal og
Åseral. Dei sender sønene sine av garde for å busetje seg der. Og nokon
kjem den andre vegen. Giftarmåla mellom dalføra er mange og påfal-
lande. Etter to–tre generasjonar stoppar denne kontakten av naturlege
grunnar opp. Det var ikkje så mykje meir eigedom og jord å gjere krav på. Søner etterfølgde fedre på odelsgardane. Dessutan vart jorda forbetra, og
dei gamle gardane tolde oppdeling i både tre og fire bruk. Tømmer vart ei viktig inntektskjelde for bøndene. Skogane langs kys-
ten var uthogne, og handelsmennene begynte å interessere seg for det
som måtte finnast innover i landet. I sør låg Flekkerøy, som på denne tida var ei av dei viktigaste ham-
nene i landsdelen for handel med korn, og ei viktig utskipingshamn for
setesdølane sitt tømmer. Arendal var også ladestad, og tømmer som vart
hogge i Finndalen i Valle vart fløyta den vegen. Reisa til Arendal fylgde
dalføra på austheia nedover mot Tovdal, Åmli eller Gjøvdal, og derfrå
vidare til byen. Lensherren sat på Nedenes, og ei gong imellom kunne det vere grunn
til å avleggje eit besøk der. Nokre gonger friviljug, til andre tider med
tvang. Jernverka ved kysten produserte jern som bøndene var avhengige
av å kjøpe då det vart slutt på å brenne eige jern. Så tidleg som på midten av 1600-talet les vi i kjeldene at også skogane
i Setesdal begynte å tømmast for tre; underforstått tre som var salsvare. Oppgjeret med kjøpmannen i byen var personleg, og som hovudregel
slik at bonden måtte take ein vesentleg del av oppgjeret i form av kjøp-
mannsvarer. Det innebar at bonden fysisk måtte reise til Kristiansand for
å få betaling, og for å hente heim dei varene han fekk som del av oppgje-
ret. Nye varer som tobakk og vin hadde gjort sitt inntog i Setesdal iallfall
så tidleg som i 1645. Nye ordningar på 1500- og 1600-talet Det veit vi mellom anna av eit brev som vart sendt til 63 kapittel 3 Bygland det året, som fortel at Jørund Kvåle skulle få dette av ein kjøp-
mann i Kristiansand som takk for god trelasthandel.18 Etter grunnlegginga i 1641 hadde Kristiansand på kort tid etablert seg
som eit administrativt, økonomisk og militært sentrum i landsdelen. I 1682 vart også biskopen flytta over frå Stavanger. Eit viktig resultat av
den administrative omorganiseringa, var at den ferdsla som tidlegare
hadde gått vestover mot Stavanger, begynte å dreie meir og meir nedover
mot Agderkysten. For bønder frå Valle sokn og nordover var turen til
Stavanger likevel enklare når dei skulle frakte med seg tunge kløver med
korn. Ulikt bøndene lenger sør i dalføret hadde eit fåtal av bøndene tøm-
mer å selje, og difor var Kristiansand ikkje eit nødvendig reisemål. På denne tida viser kjeldene at ferdsla kunne gå til mange kantar. Til
dømes frå ei tingsamling på Bygland i juni 1694 vart den dårlege opp-
slutninga frå valldølane forklåra med at «denne haarde tid hafver høylig
aarsagit dend Største dehl af dennem paa adskillige steder at omreyse,
til deris Nærings og Opholds Erlangelse, Saa at mange er udi Skeen,
andre i Kragerøe, Arendahl og Christiansand til Kornvahris Erlangelse». Kort forklart var dei utan korn, og var av garde for å skaffe nødvendig
matforsyning.19 Prosessen som til sist resulterte i at ferdsla meir og meir vart kanalisert
langsetter dalføret var alt godt i gang. 18
Jansen & Ryningen 1994, bd. VII: 254f
19
Jansen & Ryningen 1994, bd. VIII: 304 «Vejenes istandsættelse» I vår forstand var det ingen vegar på Agder før på 1800-talet. Der gamle
vegtråkk framleis er synlege, er dei å sjå som 1–1½ meter breie vegfar. Arbeidet som er gjort er dei fleste stader enkelt. Det kan vere nokre stei-
nar å trø på over ein bekk, eller ei smal bru av halvkløyvingar. I myrar
vart det lagt steinheller og tømmerstokkar, trandlar, for ikkje å søkkje
nedi. I hellande terreng vart det av og til bygt opp murar der dei fylte oppi
med sand og grus og fekk det til å verte flatare. Andre stader vart det slite
djupe renner ned i bakken som står att mest som sår i landskapet. 64 på tvers eller på langs? Så seint som rundt år 1800 var vegstellet stort sett dårleg dei fleste sta-
der. Køyreveg mellom Christiania og Kristiansand kom så seint som i
1805. Med det forstår vi ein veg der det var mogeleg å take seg fram med
hest og kjerre, altså med hjulkøyretøy. Bartholomeus von Rummelhoff vart generalvegmeister i Kristiansand
stift i 1790. Det var ei vanleg oppfatning at vegen langs kysten måtte prio-
riterast, og Rummelhoff konsentrerte seg om forlenginga av Vestlandske
Hovedvei til Stavanger. Vegar innover i landet kunne ein ikkje forvente at
skulle ha same standard, meinte Rummelhoff. Dei gamle vegane var enkle. Dette er brua over elva ved Hovden ca. 1905. Foto: August Abrahamson. Frå Aust-Agder museum og arkiv avd. Setesdalsmuseet. Dei gamle vegane var enkle. Dette er brua over elva ved Hovden ca. 1905. Foto: August Abrahamson. Frå Aust-Agder museum og arkiv avd. Setesdalsmuseet Men sterke krefter ivra for å opne meir opp for handel med dei indre
bygder. Stiftamtmann Levetzow var ein av dei som kritiserte manglande
initiativ innan vegstellet. Det gjekk så langt at generalvegmeisteren klaga
saka til det Danske Kanselli i København angåande stiftamtmannen sin
«Paastand betreffende Vejenes Istandsættelse i Raabøydelauget»: «Jeg tro-
ede det var min Hovedpligt som andre Vejmestere, og som Skikken er i 65 kapittel 3 andre Lande, først at istandsætte Postvejen, men her ansees det af lige
Vigtighed med en Bøygdewej i Raabøydelauget.»20 Den første vegstrekninga som var bygd som køyreveg i Setesdal stod
ferdig i 1804, og er den biten mellom Evje og Byglandsfjord der det ikkje
er muleg å kome fram med båt. Den vart bygd på vestsida av elva, frå
Fennefoss til Gullsmedmoen. Så skjedde det ikkje meir på lang tid. 20
Jansen et al. 2018: 43ff
21
Skar 1962: 135 «Vejenes istandsættelse» I 1827 vart ingeniørløytnant Georg Daniel Barth Johnson utnemnd
til vegmeister i Kristiansand stift. Johnson heldt fram der Rummelhoff
slapp, og Vestlandske Hovedvei vart forlenga frå Lyngdal til Stavanger. Men det var vegen opp gjennom Setesdal som vart den viktigaste opp-
gåva hans. Først på lista hans var Byklestigen, som i 1829 vart utbetra til
det han sjølv kalla kjerreveg. Med det vart også Bykle sokn knytta til byg-
dene nedanfor på ein heilt annan måte enn tidlegare. Men for den som
skulle frakte med hest, vart det framleis ein lettare tur om ein la vegen til
Valle over fjellet. Alt i 1833 la Johnson fram planar om å byggje køyreveg gjennom Setes-
dal. Stortinget fatta vedtak om vegprosjektet i 1839. Kjøpmennene i Kris-
tiansand støtta heilhjarta planane. Ikkje fordi dei så inderleg ønskte at
setesdølane skulle sleppe den strabasiøse byvegen, men fordi dei så gjerne
ville ha hand om mest mogeleg av handelen med dei indre bygder. Vegen stod ferdig frå Kristiansand til Valle kyrkje i 1846. Så langt tek-
nikken gjorde det mogeleg, var det eit mål å byggje rette vegar. I denne
perioden gjekk vegen gjerne over fjellknausar i staden for rundt dei. Ei
rekkje mindre bruer kom på plass, men over Storstraumen i Bygland og
Flårenden i Valle måtte dei reisande framleis be om å få ferjeskyss. For dølane vart turen til Kristiansand ei heilt ny oppleving: «Dø aa
hele, Dreng, no hev eg vore til by’n aa køyrt trjå tunnu’ aa stundom sat
eg på sjave, å de’ kosta alli a grand.» Aslak G. Rike hadde vore til byen
ein gong i 1840-åra og kjøpt korntønner, og grunnen til utbrotet over-
for grannen Dreng O. Rike var at han for fyrste gong hadde køyrt etter
kjerreveg like frå Kristiansand til Kilefjorden.21 66 på tvers eller på langs? Frå 1680 hadde Herefoss, no ein del av Birkenes kommune, vore ei sen-
tral bygd i Råbyggjelaget. Der residerte både skrivar og fut, og bygda var
reisemål for dei som var ute i offentlege ærend.22 Frå 1852 var båe embeta
plasserte i dalen. Futen budde på Hornnes der Postvegen gjekk like i
husveggen, og skrivaren på Klepp heilt sør i Evje sokn, slik at dei som
kom etter Postvegen måtte ha ferje over Otra. Herefoss forsvann ut av
soga som ein sentral møtestad på Agder. 22
Jansen & Ryningen 1994, bd. VII: 174
23
Moseid 2017: 15 Dampmotorane gjer sitt inntog Ikkje før var Postvegen teken i bruk, så begynte nokon å snakke om
dampbåt. I 1866 sende general Oscar Wergeland i Kristiansand – bror til
Henrik – ut ei innbyding om å stifte eit andelslag. Meininga var å kjøpe to
dampbåtar som skulle trafikkere Kilefjorden og Byglandsfjorden. Dei vedfyrte dampbåtane Bjoren og Dølen kom til Kristiansand som
«byggjesett» før jol i 1866, vart frakta opp i dalen og montert. I pinse-
helga, 8. juni 1867, gjorde Bjoren den fyrste turen mellom Kile og Horn-
nes. Same helg vart Dølen sett i rute på Byglandsfjorden.23 Trafikken nedover dalen til Kristiansand auka. Ved Kile i Hægeland
passerte vel 2500 hestar i tida frå 22. februar til 16. april i 1867. Ei større tel-
jing gjekk over eit heilt år i 1874–75. Ved Krossen passerte det mest 41 000
hestar det året, av desse 19 500 med lass. Mengda reisande indikerer at svært mykje av transporten gjekk lang-
setter dalføret. Etter folketeljinga 1875 var det 10 092 personar som budde
i Setesdal. Sjølv om det budde folk lenger nede i dalen, er det vanskeleg
å tenkje seg at volumet hadde vorte så stort om ikkje svært mange av
byreisene til dei som budde i nærliggjande område og sidedalar er talde
med her. 67 kapittel 3 Postvegen gjorde det muleg å bruke hjulkøyretøy, og frakting av varer vart mykje
enklare. Homme i Valle 1888. Foto: Axel Lindahl. Frå Aust-Agder museum og arkiv
avd. Setesdalsmuseet. Postvegen gjorde det muleg å bruke hjulkøyretøy, og frakting av varer vart mykje
enklare. Homme i Valle 1888. Foto: Axel Lindahl. Frå Aust-Agder museum og arkiv
avd. Setesdalsmuseet. Mellom anna veit vi at bøndene i Åseral på denne tida gjerne la vegen
om Hornnes, og derfrå drog etter Postvegen ned til byen. Då det kom veg
ned til Sveindal, og vidare til Mandal i 1880, vart det den nye byvegen for
åsdølane. Samstundes bad dei om å verte flytta frå Nedenes til Lister og
Mandal amt. Dermed vart kontakten med Setesdal mykje mindre enn før. I tillegg til at desse tala vart bruka som grunngjeving for utbetring av
Postvegen, vart dei også bruka som argument for å byggje Setesdalsbanen. Det er ingen tvil om at utbygginga av kommunikasjonar oppover dalføret
var av den største interesse for kjøpmennene i Kristiansand. Transport av
malm frå Evje til Kristiansand Nikkelverk var eit viktig argument. Det
same var transport av tømmer. 24
Valle kommune. Formannskapsprotokollar. Sak 29.4.1998. Dampmotorane gjer sitt inntog Setesdalsbanen stod ferdig til å takast i bruk i 1896. I april 1898 bestemte
heradstyret i Valle at det skulle etablerast telefonsentralar i alle dei tre
soknene i kommunen.24 Frå då av var det, iallfall i teorien, mogeleg å ringe
til byen om morgonen og be om å få sendt ei vare med føremiddagstoget, 68 på tvers eller på langs? og vidare om bord i ettermiddagsbåten som la til ved bryggja på Gran-
heim litt nord for Ose kl. 18.30 om ettermiddagen. Tida det tok frå ein bestilte ei vare til den var levert på garden, vart kraf-
tig redusert. Som andre stader var hamskiftet i Setesdal i gang på slutten
1800-talet, men det verkelege gjennomslaget kom ikkje før på 1900-talet. For eksempel bidrog enklare transport av kunstgjødsel til at det vart lagt
større vekt på god avling på innmarka nede i dalen. Det ekstensive hau-
stingsbruket på heiane fekk mindre betyding, men var framleis viktig så
seint som på 1950-talet. Endå meir vegbygging Også øvst i dalen hadde det skjedd store forandringar. Nytta av å knytte
Bykle saman med resten av dalen vart heftig diskutert, ikkje minst i Valle
heradstyre, der mange hadde den oppfatning at vegstellet var tilstrekke-
leg utbygd alt i 1846 med Postvegen opp til Valle kyrkje. Det som uroa
representantane mest, var nok likevel tanken på utgiftene til vedlikehald
av vegen. Men etter kvart måtte også heradstyret innsjå det fornuftige i å
byggje vegen heilt fram. Grunngjevinga var enkel, men tydeleg: Det tok
«næsten» like lang tid å reise frå Kristiansand til Valle, som dei 3 ½ mila
mellom Valle og Bykle. Dei fyrste kommunale løyvingane kom i 1858. Kommunen tok også
saka opp med amtet, og foreslo i 1865 at vegen til Bykle kunne opparbei-
dast med ei bredde på 4 alen, med unntak av «de mere bekostelige Steder»,
der ein kunne greie seg med 3 alen. Det siste var akkurat halvparten av
det lova bestemte om breidda på ein bygdeveg. Arbeidet kom i gang i 1867. Den største hindringa var Byklestigen, som var så «halsbrækkende
brat», at den ikkje ein gong fortente «Navn af Ridevei, men maatte nær-
mere betegnes som en Slags Trappe, eftersom Opstigningen skeede ved
Hjælp af Trin». På bakgrunn av eit framlegg frå ingeniørkaptein Peter
Rasmus Krag til vegdirektøren i 1875, løyvde Stortinget året etter pengar
til veganlegg frå Byklestigen til Bykle kyrkje. Anlegget vart utført 1876–
1879, og det vart sprengt ut veg i fjellsida. Då var det endeleg mogeleg for
byklarane å setje seg på kjerra og reise på bytur utan å måtte grue seg til 69 kapittel 3 den siste etappa over Byklestigen. Med det vart også Bykle knytta mykje
nærare til områda lenger sør.25 Bygdene øvst i dalen, Fjellgardane, var framleis veglause. Etter Ban-
dakkanalen, som er ein del av Telemarkskanalen, vart teken i bruk i 1892,
var dette også ei aktuell reiserute for fjellgardsfolket. Då vart handelen
gjort i Skien, og med båten fekk dei skyss heilt opp til Dalen. Med unntak av Arendalsvegen gjekk no all ferdsle nedover dalen til
Kristiansand. Det vart meir og meir sjeldan at nokon tok seg fram til fots
over viddene austover eller vestover. Når det galdt offentlege ærend var
Arendal ein nødvendig by å reise til. Endå meir vegbygging Sjølv om vi i dag ville kalle det ein
skikkeleg omveg, veit vi at mange valde å reise til Kristiansand fyrst, og
derfrå take båten vidare til Arendal.26 Ikkje før var båtane i rute før det vart sett i gong med nye trafikk
teljingar på Postvegen. Bakgrunnen var mellom anna påtrykk frå han-
delsmenn i Kristiansand som ønskte argument for ei utbetring av vegen
opp til Evje. Det er liten tvil om at dei såg på Arendalsvegen, som var
under arbeid og stod ferdig i 1908, som ein konkurrent med tanke på
frakt av «producterne af qvægavlen» frå Setesdal. 25
Jansen et al. 2018: 50
26
Åkre 2017: 295f Automobilar og automobilruter Året før Setesdalsbanen opna i 1896, kom den fyrste automobilen til Gjø-
vik. I løpet av dei neste tre tiåra skulle alt som hadde med transport å
gjere, gjennomgå store forandringar. Den fyrste bilen som kom heilt opp til Valle kom den 29. september
1909 med Ole Iglebæk frå Kristiansand som sjåfør. Lensmann Lund i
Valle var varsla, så folk visste når dei starta frå byen. Folk gledde seg til å
sjå vidunderet, men dei fleste forrekna seg, for bilen kom fleire dagar før
nokon hadde tenkt. Direktøren på nikkelverket på Evje, Gudbrand Henriksen, fekk seg bil
alt i 1911 eller -12, og det må ha vore fyrste bilen i dalen. Men bilturane var ikkje heilt problemfrie. Bilane streva mange sta-
der med bratte bakkar og krappe svingar. I 1911 løyvde Staten pengar til 70 på tvers eller på langs? omlegging av vegen mellom Byglandsfjord og Valle, og alt året etter var
arbeidet i gang. Også kommunane måtte gjeve sitt bidrag. Vi fekk ein samanhengande anleggsperiode med intens vegbygging
som ikkje vart avslutta før vegen til Hovden stod ferdig i 1935, og derfrå
vidare til Haukeli i 1939. Det som ganske fort vart eit overordna mål, var at
vegen måtte vere god nok til å tole biltrafikk. Og då talar vi om transport
av varer og menneske. For folk flest var eigen personbil eit utenkjeleg mål. Eksempel på korleis ferdslevegane gjennom generasjonar har endra seg. Kart frå boka «Frå postveg til riksveg», utarbeidd av Harald Tallaksen. Eksempel på korleis ferdslevegane gjennom generasjonar har endra seg. Kart frå boka «Frå postveg til riksveg», utarbeidd av Harald Tallaksen. 71 71 kapittel 3 Ferdsla langsetter dalen var organisert gjennom jernbanen og damp
båtane. Då er det kanskje ikkje så rart at den fyrste bilruta kom til å
gå mellom Arendal og Evje. Nils Belland starta opp med faste ruter frå
Arendal til Evje den 1. juli 1919. Den vart forlenga til Byglandsfjord i 1923,
og etter kvart heilt til Bygland om sommaren. L/L Setesdal automobilrutor vart stifta 18. desember 1919, og i mai 1920
begynte dei fyrste rutebilane å køyre. I starten trafikkerte dei strekninga
mellom Ose og Berdalsbru i Bykle. Med andre ord tok rutebilane over
på dampbåtbryggja på Ose eller på Granheim. Slik var det til vegen over
Fånefjell vart lagd om i ein halvtunell rundt fjellknausen i 1923. Det tok også litt tid før vinterbrøytinga vart organisert. 27
Jansen et al. 2018: 57f Automobilar og automobilruter Dei gamle
hestekøyrarane protesterte mot det nye, og var redde for å miste arbeidet. Og den redsla var reell nok. Men framsteget var vanskeleg å stoppe, og
frå 1929 vart det brøytt mellom Byglandsfjord og Bygland, og frå 1931 helt
opp til Valle. Etter at vegen til Hovden stod ferdig i 1935, var det i praksis
heilårstrafikk frå toppen av Setesdal til Kristiansand. Med heilårsbrøytt bilveg og rutebilar i organisert passasjertrafikk, vart
Kristiansand «Byen» for dei fleste, med Arendal på andre plass. Ikkje før
privatbilismen gjorde sitt inntog på 1960-talet, og folk kunne gjere val og
greie seg sjølve, begynte dette å forandre seg. Det var då begrepet «biltur»
oppstod som ein realitet for folk flest, der einaste føremålet med turen var
å ha ein fin dag. 27j Dampbåtane på Byglandsfjorden gav opp kampen med bilruta i 1930,
og 2. september 1962 forlot siste toget Byglandsfjord stasjon. Før nedleg-
ginga hadde det vore ein lang prosess. Mellom anna vart det bestemt at
det som erstatning skulle byggjast ein «kompensasjonsveg». Den innebar
omfattande omleggingar av traséen, og ei betydeleg heving av standar-
den. I staden for å leggje vegen der naturen la til rette for det, vart det bygt
ei rekkje nye bruer som gjorde at vegen kunne gå meir rett fram. Etter kvart som kompensasjonsvegen vart bygd ferdig, vart det lagt
fast dekke. Frå slutten av 1960-talet var det lagt asfalt eller oljegrus på det
meste av det som no heiter riksveg 9. Vårløysing og sundkøyrde vegar
var med det eit tilbakelagt problem. Den rasfarlege strekninga rundt 72 på tvers eller på langs? Fånefjellet vart løyst med ein tunell. Med den vart også problemet med
for smal veg når dei store generatorane skulle fraktast oppover dalen i
samband med kraftutbygginga løyst. Sjølv om det framleis var svingar og smale parti på vegen som gjorde at
farten måtte senkast, fekk riksveg 9 i 2003 status som «stamveg». Statens
vegvesen introduserte omgrepet i 1984 om det som var å sjå som hovud-
vegen «innanfor eit distrikt eller mellom distrikt». Dette er vegar som har
ein generelt høgare vegstandard enn andre riksvegar, sjølv om dei kan ha
mindre trafikk. Med privatbilismen har folk vorte mykje meir mobile, og trafikken går
i alle retningar. Kontakten mellom aust og vest tok seg opp då Skafså
vegen over til Dalen i Telemark kunne takast i bruk i 1965. Automobilar og automobilruter Det same
hende med Suleskarvegen over til Sirdal hausten 1990. For dei øvre byg-
der har Stavanger på ny vorte ein viktig by. Avstanden er om lag den same
som til Arendal, men litt lenger enn til Kristiansand. Nytt fylke – nye vegval? Frå 2020 er Aust- og Vest-Agder slått saman til eitt fylke. Det nye Agder
er ein trekant med ytterpunkta Flekkefjord, Hovden og Risør, der ingen
av dei to tidlegare fylkeshovudstadane ligg slik til at dei er naturlege å
peike på som sentrale midpunkt. I god tid før fylkessamanslåinga er mykje godt vegarbeid utført innover
Hovlandssdalen mellom Evje og Arendal. Sjølv om vegen til Kristiansand
framleis er litt kortare og vegen litt beinare, er eg ganske sikker på at
mange dølar framleis kjem til å leggje vegen over heia. Åseral har etter søknad i 2019 vorte godkjent som fullverdig medlem
av Setesdal regionråd. Dermed har dei på sett og vis teke tilbake den stå-
staden dei hadde før vegen til Mandal stod ferdig i 1880. Det som etter samanslåinga har vorte eit tilnærma geografisk midt-
punkt i det nye Agder, er Evje. Om det er nok til endå ein gong å endre
på kommunikasjonslinene i landsdelen, får vi la framtida gjeve svar på. 73 kapittel 3 Litteratur Dybdahl, K. D. (1947). Pilegrimmenes og bispenes vei. Utsnitt av et brev fra P. A. Dybdahl, K. D. (1947). Pilegrimmenes og bispenes vei. Utsnitt av et brev fra P. A. Munch. Kristiansand og Opland turistforening. Munch. Kristiansand og Opland turistforening. Gjellebøl, R. (1800). Beskrivelse over Sætersdalen i Christiansands Stift. Topographisk Journal 26 hefte Gjellebøl, R. (1800). Beskrivelse over Sætersdalen i Christiansands Stift. Topographisk Journal, 26. hefte. t
Jansen, L., Haugen, P. A., Røysland, O. & Tallaksen, H. (2018). Frå postveg til riksveg
– vegar og vegminne langs riksveg 9. Bokbyen forlag. Jansen, L. & Ryningen, A. (1994). Valle kommune. Kultursoge: Bd. VII–VIII. Valle
kommune. Jansen, L. & Ryningen, A. (1994). Valle kommune. Kultursoge: Bd. VII–VIII. Valle
kommune. Larsen, J. H. (1980). Vikingtids handelsplass i Valle, Setesdal (UO- skrifter nr. 3). Universitetets oldsaksssamling. Larsen, J. H. (1980). Vikingtids handelsplass i Valle, Setesdal (UO- skrifter nr. 3). Universitetets oldsaksssamling. Larsen, J. H. (2013). Gravene og bosetningen. I L. Jansen, I. Paulsen & N. O. Sundet
(Red.), Spor i Setesdalsjord, s. 55–70. Bokbyen forlag. Mjærum, A. & Larsen, J. H. (2013). Jernvinna i Setesdal – selvforsyning og
storindustri. I L. Jansen, I. Paulsen & N. O. Sundet (Red.), Spor i Setesdalsjord,
s. 101–120. Bokbyen forlag. Moseid, T. (2017). Frå kveg til cruise. D/S Bjoren 150 år. Setesdalsmuseet. Orknøyingasoga. (1929). (Gustav Indrebø, umsetj.). Det Norske Samlaget. Ryningen, A. (1987). Valle kommune. Gards- og ættesoge Valle bd. VI. Valle
kommune. Skar, J. (1961). Gamalt or sætesdal. Band II. Det Norske Samlaget. Steen, S. (1929). Ferd og fest. Reiseliv i norsk sagatid og middelalder. Aschehoug. Wenn, C. C. (2016). Rv. 9 Krokå–Langeid. Del II: Gravfelt fra vikingtid (Rapport,
arkeologisk utgravning). Kulturhistorisk museum & Universitetet i Oslo. http://urn.nb.no/URN:NBN:no-53871 Åkre, T. (2018). Ferdslevegar i Sætesdal. I O. M. Holen (Red.), Meir gamalt or
Sætesdal. Bokbyen forlag. 74 Sitering av dette kapitlet: Johnsen, B.E. (2020). Hva var det med Lillesand? Argumenter for valg og
vraking av stortingsrepresentanter 1862–1931. I Johnsen, B.E. og Vadum, K. (red.), Grenseløst Agder. Det
som skilte og det som bandt (s. 75–103). Oslo: Cappelen Damm Akademisk. https://doi.org/10.23865/
noasp.111
Li
CC BY NC ND 1
Kristian Sundtoft, stortinget.no; Kristian Sundtoft, Wikipediahh 2
Arne Thomassen, stortinget.no; Arne Thomassen, Wikipedia kapittel 4
Hva var det med Lillesand?
Argumenter for valg og vraking av
stortingsrepresentanter 1862–1931 kapittel 4 3
Udjus 2018 4
Jorunn Gleditsch Lossius, stortinget.no kapittel 4 Berit Eide Johnsen Fram til fylkessammenslåingen 1. januar 2020 var Lillesand en utkant i
Aust-Agder. I sammenheng med stortingsvalg fikk man lenge inntrykk
av at kandidater fra denne kommunen, faretruende nær Kristiansand,
nærmest ble regnet som «politisk spedalske». Kristian Sundtoft (Høyre)
stilte flere ganger til valg, men fikk aldri fast plass på Stortinget. Han
møtte bare som vararepresentant i til sammen 30 dager i årene 1965–1997.1
I 1998 meldte han seg ut av Høyre og året etter inn i Venstre, i ren protest
og frustrasjon over sine tidligere partifeller. Det var særlig deres mot-
stand mot ett Agder, og marginaliseringen av Lillesand, som lå under. Arne Thomassen (Høyre) fikk smake den samme medisinen. Han opp-
nådde ikke sikker plass i nominasjonsprosessen, og ble heller ikke valgt
til stortingsrepresentant, verken i 2009, 2013 eller 2017.2 «Jo lenger øst du
har kommet i Aust-Agder, desto mer suspekt har Lillesand vært», konsta-
terte politisk redaktør i Fædrelandsvennen, Vidar Udjus, i november 2018. Men han fastslo samtidig at situasjonen plutselig var blitt snudd på hodet. Arne Thomassen var nemlig blitt valgt til Høyres fylkesordførerkandidat.3 75 kapittel 4 kapittel 4 Ingressen på nevnte kommentarartikkel slo fast at «den første vin-
neren av fylkessammenslåingen er allerede klar: Lillesand». Den fore-
stående fylkessammenslåingen endret det mentale og faktiske kartet:
Lillesand var ikke lenger i periferien av Aust-Agder, men midt i Agder. Både den første fylkesordføreren i det nye Agder – Arne Thomassen – og
opposisjonslederen – Gro Bråten (Arbeiderpartiet), som inntil utgangen
av 2019 var fylkesordfører i Aust-Agder – kommer derfra. Og Jorunn
Lossius (Kristelig folkeparti) møter som fast vararepresentant på Stortin-
get.4 Vi må tilbake til før 1920 for å finne en tilsvarende sterk Lillesands-
representasjon regionalt og nasjonalt. Hvor lenge ble Lillesand marginalisert? Kanskje allerede fra 1921, da
en ny stortingsvalgordning endret områdets status fra relativt sentralt
plassert i Sand krets til en utkant i Aust-Agder fylke. Muligens hadde
også utviklingen fra valg uten politiske partier, via topartisystem til
flere partier betydning. (Se nedenfor om valgordningen.) Og om ikke
før, så skjedde det noe i forbindelse med åpningen av Varoddbrua i
1956 og den nye stamveien mellom Kristiansand og Lillesand, som ble
åpnet i 1960. Kristiansands sentrifugalkraft sugde deretter Lillesand til
seg, noe som økte avstanden til Aust-Agders fylkeshovedstad, Arendal. Men på 1800-tallet og i første del av 1900-tallet var situasjonen anner-
ledes. Da var det nemlig fullt ut mulig for en lillesander å bli valgt til
stortingsrepresentant. I dette kapitlet er ikke temaet valgene fram til i dag. Det skal der
imot dreie seg om argumenter for valg og vraking av stortingsrepresen-
tanter fra Lillesandsområdet i årene 1862–1931. I løpet av disse knappe
70 årene kom det nemlig fire stortingsrepresentanter derfra. I 1862 hadde
det gått 30 år siden den forrige stortingsrepresentanten hadde blitt valgt
fra dette lokalområdet, gårdbruker Christen Andersen Østre Vallesverd
(1797–1842) fra Høvåg. Han satt på Stortinget 1833–35. Noen fast repre-
sentasjon på Stortinget har ikke nåværende Lillesand kommune (før 1962
bykommunen Lillesand og landkommunene Vestre Moland og Høvåg)
hatt siden 1918, det vil si de siste vel hundre årene. 76 hva var det med lillesand? I april 1862 ble losoldermann Jacob Svendsen (1823–93) valgt til stor-
tingsmann i det indirekte valget i Nedenes amt, som da ble avholdt i
Arendal. Han ble deretter vraket flere ganger, men oppnådde å bli valgt
for ytterligere én periode: 1874–76. De tre øvrige var skipsreder J. A. Henschien (1836–95), som ble valgt i det indirekte valget i Nedenes amt
for periodene 1892–94 og 1895–97, skolebestyrer og redaktør Noan Chr. 5
Hans Thorvald Hansen var skipsfører til 1903, deretter skipsreder, dampskipsekspeditør (fra
1911) og havnefogd. Han var medlem av bystyret i 16 år fra 1908, og hadde mange kommunale
verv. I 1912 ble han valgt til ordfører ved loddtrekning, men måtte si fra seg vervet fordi han like
etter fikk stillingen som havnefogd. Biografiske opplysninger: Lindstøl 1914a: 338; Rosenberg
1990: 19–20; Stangeby 2011: 6–7, 11. 6
Stangeby 2011: 11 skriver feilaktig: «I fire år var han varamann til Stortinget og […] møtte […]
stort sett alle årene […].» Stortingsperioden var tre år, 1910, 1911 og 1912, og Hansen møtte de to
siste årene, 1911 og 1912, under B. K. Imenæs’ sykdom. Han var medlem av protokollkomiteen. kapittel 4 Gauslaa (1864–1952), som ble valgt i direkte valg i enmannskrets for tre
perioder fra 1907 og var møtende vararepresentant 1922–31, samt havne-
fogd Hans Thorvald Hansen (1854–1931), som møtte som vararepresen-
tant 1911–12.5 Henschien var bosatt i Vestre Moland, like utenfor grensene
til ladestedet Lillesand. De tre andre var bosatt i selve tettstedet Lillesand. Hansen satt bare en kortere periode på Stortinget, og representerte Fri-
sinnede Venstre i valgsamarbeid med Høyre.6 Lite er undersøkt om hans
virke der. I det følgende vil derfor oppmerksomheten bli rettet mot de tre
øvrige: Svendsen, Henschien og Gauslaa. Hva var bakgrunnen for at disse representantene ble valgt? Hvilke
standpunkter inntok de, og hvilke interesser representerte de? Hvordan
ble de valgt, og hvem stemte på dem? Hvordan var argumentasjonen
på valgforsamlingene og i forbindelse med valgkampene? Hvilke riks
politiske saker var det som vakte særlig engasjement i lokalmiljøet, og
hvordan virket det inn på valgene? I perioden 1862–1931 ble de lokale forholdene gradvis, og i langt større
grad enn tidligere, influert av nasjonale utviklingstrekk og beslutninger. På sørlandskysten fulgte man derfor godt med i hva som ble diskutert og
besluttet på Stortinget, i regjeringen og av Kongen. Det gjaldt ikke minst
innen skipsfarten. Men bakgrunnsteppet er også den rikspolitiske pola-
riseringen fra 1860-tallet, den som endte opp med dannelsen av partiene
Venstre og Høyre i 1884, innføringen av parlamentarismen og utnevnelsen 77 kapittel 4 av den første venstreregjeringen med Johan Sverdrup som statsminister. Andre viktige politiske saker var unionsoppløsningen og kongevalget i
1905, samt innføringen av kvinnestemmeretten i 1913. På denne tiden var
også avholdssaken og kirkespørsmål viktige sakskomplekser som skapte
stort engasjement og skarpe politiske skiller. Mange av tidens viktige politiske spørsmål og diskusjoner vakte stort
lokalt engasjement. Det kan vi få bekreftet når vi undersøker lokalavisene. I siste del av 1800-tallet ble det mer vanlig å lese aviser. Den vestlandske
Tidende, den konservative avisen som utkom i Arendal, ble eksempel-
vis lest av mange. Det samme gjaldt kristianiaavisen Morgenbladet. Men
ikke minst etter at Lillesands-Posten kom ut med sitt første nummer
9. september 1870, fulgte lokalbefolkningen med som aldri før. Denne
venstreavisen fikk etter noen år – tilskyndet av at de politiske frontene
tilspisset seg – sitt konservative motstykke i Lillesands Tidende (1882–84
og 1918–21) og Lillesands Tilskuer (1886–1918). Valgordning og valgdeltakelse Før vi går nærmere inn på valg og vraking av stortingsrepresentantene
fra Lillesandsområdet, er det viktig å ha valgordningen klart for seg. For
det første: Det var stortingsvalg hvert tredje år til og med valget i 1936. For
det andre: Kjøpstedene utgjorde egne valgkretser inntil 1949. I Nedenes
amt gjaldt det Grimstad og Arendal (sammen) samt Risør. Ladestedene,
deriblant Lillesand, utgjorde til og med valget i 1903 en felles valgkrets
sammen med landdistriktene i amtet. For det tredje: Fram til og med 1903
var det indirekte flertallsvalg (med valgmenn som igjen valgte stortings-
representanter). Prinsippet var at «the winner takes it all». Med andre
ord: Den konstellasjonen som hadde flertall, fikk samtlige stortings
representanter. I perioden 1906–1918 var det derimot direkte flertallsvalg
i enmannskretser. Arendal–Grimstad (i fellesskap) og Risør valgte nå
som før hver sin representant, mens resten av amtet var inndelt i fire
kretser: Holt, Nedenes, Sand og Setesdal. De skulle velge hver sin stor-
tingsrepresentant med personlig vararepresentant. Men så, fra og med
valget i 1921, ble systemet igjen endret, denne gangen til forholdstallsvalg 78 hva var det med lillesand? i flermannskretser. Aust-Agder fylke, som det het fra 1919, utgjorde fra da
av én krets. Og for det fjerde: Landdistriktene i Nedenes amt valgte tre
stortingsrepresentanter fram til 1859, og deretter fire. Tabell 1. Valgordningen ved stortingsvalg og representasjon fra Lillesand
1814–1903
1906–1918
1921–i dag
Valg hvert tredje år
Valg hvert tredje år
Valg hvert tredje år til og med
1936. Funksjonstiden endret
til fire år i 1938. Indirekte flertallsvalg
Direkte flertallsvalg i
enmannskretser
Forholdstallsvalg i
flermannskretser
I prestegjeldene/
herredene (inklusive
ladestedene) ble det valgt
valgmenn, som igjen valgte
stortingsrepresentanter. Nedenes amt utgjorde én
valgkommune. Kjøpstedene var egne
valgkommuner. Sand krets i Nedenes
amt bestod av herredene
Herefoss, Fjære, Landvik,
Eide, Birkenes, Vestre Moland
og Høvåg samt ladestedet
Lillesand. Byene var egne kretser. Aust-Agder fylke (fra 1919)
var én valgkrets. 1949: Siste stortingsvalg med
egne bykretser. Jacob Svendsen:
1862–64 og 1874–76. J. A. Henschien:
1892–94 og 1895–97
N. Chr. Gauslaa:
1907–09, 1913–15 og 1916–18. Hans Thorvald Hansen:
1911–12 (fast møtende
vararepresentant)
N. Chr. Gauslaa:
1922–31 (vararepresentant,
møtte flere ganger)
Kristian Sundtoft:
1965–69, 1981–85, 1993–97
(vararepresentant, møtte i til
sammen 30 dager)
Arne Thomassen:
2009–21:
(vararepresentant, har møtt
18 dager)
Jorunn Gleditsch Lossius:
2017–2021 (vararepresentant,
har møtt fast fra januar 2019) Hvor mange var det som stemte? 7
Statistisk sentralbyrå, 1895: 119. I byene skilte prosenttallene for de stemmerettskvalifiserte og de
stemmeberettigede seg ikke vesentlig fra landdistriktene. Men en høyere andel avla sin stemme
ved stortingsvalgene. Dette tallet varierte imidlertid sterkt. Andelen stemmeberettigede som
avla sin stemme 1859–82 var i byene i Nedenes amt: Risør 56 %; Arendal 53 %; Grimstad 36 %.
Andelen var vesentlig høyere i Kristiansand: 75 %. Valgordning og valgdeltakelse Faktum er at en svært liten andel av
den norske befolkningen stemte ved kommune- og stortingsvalgene på
1800-tallet. Fram til valget i 1909, da kvinner hadde begrenset stemmerett,
var det bare menn som kunne stemme ved stortingsvalg. Først i 1913, med
virkning fra valget 1915, oppnådde kvinner allmenn stemmerett. I tidsrommet 1859–82 var i gjennomsnitt bare 7,5 prosent av den norske
befolkningen i landdistriktene, der Lillesand, Vestre Moland og Høvåg 79 kapittel 4 hørte hjemme, stemmerettskvalifiserte. Det gjaldt et litt høyere antall, åtte
prosent, i Nedenes amt. Men bare 5,2 prosent av den norske befolknin-
gen på landet stod i manntallet og var stemmeberettigede (4,9 prosent i
Nedenes amt) i denne perioden. Og en enda mindre andel avla faktisk sin
stemme: Ved stortingsvalgene mellom 1859 og 1882 gjaldt det i gjennom-
snitt 47 prosent av de stemmeberettigede nordmenn på landet (og like
under 50 prosent i landdistriktene i Nedenes amt).7 Fra og med 1882 var det flere stemmeberettigede og økende valg
deltakelse. Ved «riksrettsvalget» dette året, som mange har sett på som
det første moderne valget i Norges historie, steg temperaturen mange
hakk, og valgdeltakelsen var rekordhøy. Eksempelvis benyttet hele
93 prosent av de stemmeberettigede i Lillesand og Vestre Moland seg nå
av stemmeretten. Men det dreide seg bare om 149 menn – under tre pro-
sent av innbyggerne. Vi kan anta at det først og fremst var i ladestedet Lillesand at den poli-
tiske temperaturen var steget, og at valgdeltakelsen dermed hadde gått
opp i 1882. Generelt var valgdeltakelsen nemlig høyere i kjøp- og lade-
stedene enn i landdistriktene. Men til tross for dette er det i landdistrik-
tene med ladestedene vi kan forvente de største interessekonfliktene – og
uansett interessekonflikter av en helt annen type – enn i bykretsene. Her
stod ladestedene mot bygdene, og kysten mot innlandet. Her stod land-
bruksnæringen mot bynæringene – sistnevnte dominert av de maritime
næringene. Hvordan slo valgordningen, valgdeltakelsen og interessekonfliktene ut
ved valg av stortingsrepresentantene fra Lillesandsområdet? 80 hva var det med lillesand? 10
Blant Jacob Svendsens øvrige lokale verv kan nevnes at han var valgmann, medlem av skole
kommisjonen og forlikskommissær. I Lillesands Sparebank hadde han flere tillitsverv fra 1858,
både som forstander, medlem av kontrollkomiteen og medlem av direksjonen, samt som ban-
kens formann i 1880. 8
Biografiske opplysninger om Jacob Svendsen bygger på Gauslaa 1927: 22; Lindstøl 1914b: 853;
Rosenberg 1990: 18–19.
S d l 11
Gauslaa 1927: 22 9
Sødal 2013: 394 Jacob Svendsen
– representant for sjøfarten og småbyen Jacob Svendsen (1823–93). Foto: Stortingsarkivet. Den første stortingsmannen som vi skal ta for oss,
er losoldermann Jacob Svendsen. Han ble to gan-
ger valgt til stortingsrepresentant, og stilte til valg
ytterligere fem ganger uten å bli valgt.8 Svendsen vokste opp på gården Holte i Høvåg,
som sønn av en sjømann og tidligere prisonfange
fra krigen 1807–14. Han var selv sjømann i flere år,
ble skipsfører bare 25 år gammel, og overtok navi-
gasjonsskolen som faren drev på gården.9 På 1850-tallet var han et par år bosatt i Vestre
Moland, før han i 1856 flyttet til Rosenberg like
innenfor ladestedet Lillesands grenser. Her drev
han navigasjonsskolen videre. Fra 1859 var han
losoldermann og havnefogd i Lillesand, og året
etter ble han innrulleringsbetjent med ansvar for
mønstring av sjøfolk. Jacob Svendsen (1823–93). Foto: Stortingsarkivet. I hele 35 år var Svendsen medlem av bystyret, fra
1858 og til han døde i 1893. Dessuten var han byens
ordfører 1870–75 og i årene 1879–80, 1885 og 1887, samt viseordfører i de
mellomliggende årene. Han hadde også mange andre verv.10 I Lillesands
Sparebanks jubileumshefte fra 1927, ført i pennen av en annen stortings-
mann, N. Chr. Gauslaa, blir Svendsen omtalt som «en for offentlig virk-
somhet sterkt interessert mann og en sjelden sympatisk personlighet,
som må nevnes med heder i byens annaler».11
Jacob Svendsen (1823 9
Foto: Stortingsarkivet. 81 kapittel 4 Jacob Svendsen ble altså valgt inn på Stortinget fra Nedenes amt i to
perioder, og satt der 1862–63, 1864 (et overordentlig storting, dvs. sam-
menkalt etter at det ordinære stortinget var oppløst) og 1874–76.12 I årene
mellom de to stortingsperiodene var Svendsen i flere år suppleant (dvs. vararepresentant): andre suppleant 1865–66 og første suppleant 1871–73.13 Det vi må ha i bakhodet når vi skal se på hvorfor Svendsen to ganger
ble valgt og fem ganger vraket, er at de politiske partiene ennå ikke var
etablert i 1860- og 70-årene. Men rikspolitikken var likevel klart splittet i
en venstre- og høyreside. Etter at Jacob Svendsen i 1862 hadde vunnet den tredje av de fire stor-
tingsplassene fra bygdene i Nedenes amt, ble han vraket både i 1865, 1868
og 1870.14 Hvorfor? Lillesands-Posten, som utkom fra høsten 1870, er en
sentral kilde til svaret på hvorfor han ikke ble gjenvalgt sistnevnte år, og
vi kan legge til grunn at argumentene i stor grad også er dekkende for de
foregående valgene. 15
Lillesands-Posten 7.10. 1870 12
Valget 8. april 1862 var til det 17. ordentlige Storting som satt samlet 1.10.1862–22.6.1863 og det
6. overordentlige Storting som satt samlet 14.–31.3.1864. Valget 22. november 1873 var til det 23.
ordentlige Storting som satt samlet 2.2.–6.6.1874, 1.2.–11.6.1875 og 1.2.–13.6.1876. Lindstøl 1914c.
b S
d
dl
k
llk 14
De to kandidatene som ble valgt på de første plassene i stortingsvalget for Nedenes amt i 1862,
var gårdbrukerne H. T. Skjerkholt og O. T. Lindstøl. Losoldermann Svendsen fikk i likhet med
ingeniørløytnant P. R. Krag 19 stemmer, men ved loddtrekning vant Svendsen den tredje og Krag
den fjerde og siste stortingsplassen. Lindstøl 1914c: 315. 12
Valget 8. april 1862 var til det 17. ordentlige Storting som satt samlet 1.10.1862–22.6.1863 og det
6. overordentlige Storting som satt samlet 14.–31.3.1864. Valget 22. november 1873 var til det 23.
ordentlige Storting som satt samlet 2.2.–6.6.1874, 1.2.–11.6.1875 og 1.2.–13.6.1876. Lindstøl 1914c.
13
Jacob Svendsen var medlem av næringskomite nr. 2 1862–63 og tollkomiteen 1874–76.
14
De to kandidatene som ble valgt på de første plassene i stortingsvalget for Nedenes amt i 1862,
var gårdbrukerne H. T. Skjerkholt og O. T. Lindstøl. Losoldermann Svendsen fikk i likhet med
ingeniørløytnant P. R. Krag 19 stemmer, men ved loddtrekning vant Svendsen den tredje og Krag
den fjerde og siste stortingsplassen. Lindstøl 1914c: 315.
15
Lillesands-Posten 7.10. 1870 Jacob Svendsen
– representant for sjøfarten og småbyen I begynnelsen av oktober 1870 stod et anonymt leserinnlegg i Lille-
sands-Posten. Signaturen «z» bestred ikke Svendsens evner og dyktighet
som tingmann, og ville heller ikke ha noe imot at Svendsen representerte
amtet på tinget: «Han skilte sig vistnok godt fra sit Hverv baade i Komit-
teen og i Thingsalen i formel Henseende.» Men «z» hevdet at det var vel-
gernes mening at Svendsen «ikke iagttog Landdistriktets Tarv ligeoverfor
Byinteresserne, og dette er det som har skubbet ham tilside nu tvende
Gange, og der er nok lidet Haab om, at han nogensinde overvinder disse
Nederlag».15 I en redaksjonell artikkel 17. november 1870 ble «Amtets Thingmænd»
vurdert. Den som Lillesands-Posten fant «bedst skikket til at indtage Lie-
støls Plads», var losoldermann Svendsen. 82 hva var det med lillesand? Det har været til liden Ære for Amtet, at dets Valgmænd i saa lang Tid har
kunnet udstænge denne Mand, og det turde maaske gjøre noget Indtryk, naar
vi oplyse, at ogsaa Ueland fandt denne Handlemaade utilbørlig. Naar man
vrager Svendsen […] maa der med Tiden komme en Reaktion; thi det er ikke
for stærkt sagt, at man ved en saadan Fremgangsmaade vrager Dygtigheden
og bænker Middelmaadigheden til Høisædet. […] I et Amt som Nedenæs, der
har saa store Interesser paa Søen, burde dog ikke Svendsen skubbes tilside for
rene Bænkeryttere og Stemmemaskiner, og vi forvente, at Valgmændene fra
Kystdistrikterne ville samle sig om denne Amtets mest insigtsfulde Repræsen-
tant for vor Skibsfart.16 Her ser vi altså at Lillesands-Posten ikke bare trakk fram Jacob Svendsen
som en kandidat fra eget distrikt og la vekt på hans dyktighet, men også
at han representerte kysten og hadde innsikt i skipsfarten. Både signaturen «z» og Lillesands-Posten redaksjonelt talte varmt for
Svendsen, men til ingen nytte. Som bymann og først og fremst forbun-
det med skipsfartens interesser nådde han ikke opp. I Nedenes amt stod
kysten og småbyen mot innlandet, og sjøfartsinteressene mot jord- og
skogbruket. Det ble fire gårdbrukere som kom til å representere Nedenes
amt på Stortinget i perioden 1871–73.17 Gjorde Jacob Svendsen en dårlig jobb på Stortinget? Nei, det ser ikke
ut til at det var en vanlig oppfatning. 17
De fire gårdbrukerne som kom på Stortinget fra landdistriktene i Nedenes amt i 1870, var Ole
Torjesen Lindstøl, Halvor Torjussen Skjerkholt, Nils Pedersen Igland og Knud Larsen Liestøl
(også lensmann). Lindstøl 1914c. 16
Lillesands-Posten 17.11. 1870i 18
Worm-Müller 1935: 578–79 16
Lillesands-Posten 17.11. 1870i 16
Lillesands-Posten 17.11. 1870
17
De fire gårdbrukerne som kom på Stortinget fra landdistriktene i Nedenes amt i 1870, var Ole
Torjesen Lindstøl, Halvor Torjussen Skjerkholt, Nils Pedersen Igland og Knud Larsen Liestøl
(også lensmann). Lindstøl 1914c.
18
Worm-Müller 1935: 578–79 Jacob Svendsen
– representant for sjøfarten og småbyen I et leserinnlegg i Lillesands-Posten
høsten 1870 het det: «Ved at sende Svendsen paa Thinget vil man ialfald
have den Tilfredsstillelse ikke alene at faa høre, at Representanten har en
Mening, men ogsaa hvordan denne Mening er.» Det må ha passet svært
bra for skipsføreren, navigasjonslæreren, losoldermannen og havnefogden
fra småbyen Lillesand å bli medlem av næringskomite nr. 2 på Stortinget
i 1862. Her brukte nemlig Svendsen aktivt sine erfaringer som sjømann. I storverket Den norske sjøfarts historie fra 1935 skriver Jacob S. Worm-Müller at Svendsen «bragte en sjøfrisk aand ind i odelstings
debatten» da emigrantloven av 1863 skulle behandles.18 Et viktig spørsmål 83 kapittel 4 var om det skulle være tillatt å frakte emigranter til Amerika i samme
skipsrom som salt fetsild i tønner, makrell og tørrfisk. Fra fiskeeksport-
områdene på bergenskanten og i Nordland ble det protestert heftig mot
skjerpede krav til emballasje, som man mente ville stanse eksporten. Lukten var ubehagelig, ja, rent ut avskyelig, men ikke sunnhetsskadelig,
hevdet noen. Andre talte for god ventilasjon. Svendsen viste til at det var ytterst ubehagelig at hundre mennesker
befant seg i samme rom som 600 tønner sild under en storm i Atlanter-
havet. Han skulle ønske at Lagtinget «nogensinde i en storm i 24 timer
hadde befundet sig paa tyskendæk i et fartøi med sild og fiskeladning om
bord». Han understreket at emigrantene ikke dro frivillig i et skip med
fisk og sild. De hadde jo tinget overfarten uten å vite noe om den øvrige
lasten, og når de kom til Bergen, var de ofte nødt til å gå om bord fordi
det ikke var annet skip å få. Resultatet ble at den innskjerpede emballasje
bestemmelsen til slutt ble vedtatt av sunnhetshensyn. Høsten 1873 stilte Svendsen til valg igjen. Nå ble han valgt som fjerde
og siste representant for bygdene i Nedenes amt, og kom på Stortinget
for andre gang.19 Lillesands-Posten rapporterte i den forbindelse at man
«I almindelighed hører […] udtale den største Tilfredshed med Udfal-
det af Storthingsvalget for Nedenæs». I det relativt knappe referatet fra
valgforsamlingen i Arendal framgår det at årsaken til tilfredsheten var
at de utkårede var «prøvede Mænd, som under deres Virken have lagt
for Dagen, at de ei alene interesserer sig for det offentlige Stel, men at de
ogsaa have Kundskab og Færdighed til let og sikkert at sætte sig ind i
nye og mere vanskelige Sager». 19
I stortingsvalget for Nedenes amt i 1873 ble lensmann L. K. Liestøl, landhandler A. T. Holm og
gårdbruker O. T. Lindstøl ble valgt på de tre første plassene. Lindstøl 1914c: 384.
20
Lillesands-Posten 28.11.1873 Jacob Svendsen
– representant for sjøfarten og småbyen Personlige egenskaper – kunnskaper og
ferdigheter – ble altså sterkt vektlagt.20 Men gode personlige egenskaper var ikke nok. Etter to perioder på
Stortinget – og tre mislykkede forsøk – stilte Jacob Svendsen igjen til valg
i 1876, og for siste gang i 1879 – for sjuende gang. Men han ble vraket begge
gangene. Hvorfor? I stor grad kan det ha skyldtes de skjerpede politiske
motsetninger mellom en konge- og regjeringstro høyreside (der Svend-
sen befant seg) og en venstreside i opposisjon på Stortinget. Men det kan 84 hva var det med lillesand? også forklares med valgordningen, det indirekte flertallsvalget der «the
winner took it all». Fra Nedenes amt ble nemlig fire gårdbrukere valgt
både for perioden 1877–79 og 1880–82. Venstresiden gjorde rent bord. I 1879 var statsrådssaken det mest brennende politiske spørsmålet. Det
dreide seg om kongens veto, riksrett og motstand mot parlamentarismen. Svendsen hadde først, i likhet med andre representanter på høyresiden,
stemt mot statsrådenes adgang til Stortinget. Men i 1879 uttalte han der-
imot at de som nå ble valgt, burde stemme for statsrådssaken. Forresten
trodde han ikke, tilføyde han, at «det burde øve nogen Indflydelse paa
Valget, enten Repræsentanterne stemte for eller imod denne Sag; han tro-
ede ikke der burde lægges saadan Bræt paa denne Sag, da den vilde gaa
igjennem ligefuldt». På det tidspunktet karakteriserte han seg forøvrig
som «liberal», noe han mente man «i Bund og Grund [kunde] være […]
uden at stemme for denne Sag». 21 Venstrerepresentantene ville derimot
reservere begrepet «liberal» for Sverdrups tilhengere, altså venstresiden. I 1879 var statsrådssaken det mest brennende politiske spørsmålet. Det
dreide seg om kongens veto, riksrett og motstand mot parlamentarismen. Et annet forhold var sparepolitikken. En av valgmennene uttalte i 1879
at grunnen til at Svendsen ikke var blitt gjenvalgt i 1876, var at «Lands
folket var bange for, at han vilde vedblive at være for flot i Bevilgnings-
sager. Han svarede ikke til de Begreber om Sparsommelighed, som de
fleste af Amtets Valgmænd nærede». Det ble spesielt vist til at han hadde
støttet bevilgninger til jernbaner. Svendsen stod altså ikke for den spare-
politikken som særlig bondetingmennene på venstresiden representerte,
og som på det tidspunktet hadde oppslutning fra et flertall av valgmen-
nene i Nedenes amt. 21
Lillesands-Posten 4.12.1879 (etter Agderposten). Følgende sitater: samme referanse. Jacob Svendsen
– representant for sjøfarten og småbyen En tredje grunn til at han ikke ble valgt, fortsatte en annen av valg-
mennene, var at man hadde funnet ut at han som bymann «stod altfor
meget paa Byinteresserne mod Landdistrikterne». Etter dette konklu-
derte Svendsen med at hans «Lyst til at komme paa Thinget var nu meget
liden». Det vi kan konkludere med, er at Svendsen i stor grad representerte
vage, upopulære og muligens uavklarte standpunkter til tidens bren-
nende rikspolitiske sakskomplekser og stridsspørsmål. Han var med
andre ord vinglete. Vi aner også at den politiske polariseringen som 85 kapittel 4 foregikk i rikspolitikken og på Stortinget på 1860- og 70-tallet, på mange
måter var i utakt med de lokale motsetningene – by og land, sjøfart og
jord/skogbruk. Svendsen representerte klare lokale interesser – sjøfarten
og småbyen, og var talerør for disse på Stortinget. Men i en periode da
politikken ble polarisert, og da rikspolitiske saker fikk forrang, var et
brennende engasjement for kysten og sjøfarten ikke tilstrekkelig til å bli
valgt. Svendsens offentlige virke begrenset seg de følgende årene til lokale
verv og lokalpolitikken. 22
Centrum var utbryter fra Venstre i 1893, og stilte til valg mellom 1893 og 1900. Partiet er ofte
sett på som en østlandsk avlegger av Moderate Venstre. Centrum, Wikipedia; Moderate Venstre,
Wikipedia. 22
Centrum var utbryter fra Venstre i 1893, og stilte til valg mellom 1893 og 1900. Partiet er ofte
sett på som en østlandsk avlegger av Moderate Venstre. Centrum, Wikipedia; Moderate Venstre,
Wikipedia.
23
I Henschiens stortingsperioder var disse regjeringene: Johannes Steens første venstreregjering
(6.3.1891–2.5.1893) og Emil Stangs andre høyreregjering (2.5.1893–14.10.1895).
24
Biografiske opplysninger om J. A. Henschien bygger på notat v/ Kjell Rosenberg (med avskrift av
nekrolog i Lillesands Tilskuer 5.9.1895); Lindstøl 1914a: 367. 24
Biografiske opplysninger om J. A. Henschien bygger på notat v/ Kjell Rosenberg (med avskrift av
nekrolog i Lillesands Tilskuer 5.9.1895); Lindstøl 1914a: 367. 23
I Henschiens stortingsperioder var disse regjeringene: Johannes Steens første venstreregjering
(6.3.1891–2.5.1893) og Emil Stangs andre høyreregjering (2.5.1893–14.10.1895). 27
Den vestlandske Tidende 24.11.1891; Liste over stortingsrepresentanter 1892–1894, Wikipedia. 25
Blant J. A. Henschiens lokale verv og oppgaver kan nevnes at han var formann i direksjonen for
Vestre Molands Sparebank, forlikskommissær, herredsstyremedlem og valgmann (første gang i
1879), foruten ordfører i 12 år. 26
Lillesands Tilskuer 5.9.1895. Følgende sitat: samme referanse. J. A. Henschien – skipsfører, reder og verftseier Den andre stortingsmannen fra Lillesandsområdet som ble valgt inn på
Stortinget i perioden 1862–1931, var Johannes Andreas Henschien. Han
ble i likhet med Jacob Svendsen valgt to ganger: høsten 1891 (for perio-
den 1892–94) og høsten 1894 (for perioden 1895–97). I første periode stilte
han for Moderate Venstre, og deretter for Centrum. Begge disse partiene
inngikk fra omkring 1900 i samarbeid med Høyre.22 Også han befant seg
altså på den politiske høyresiden – men den mer moderate delen av den. Han var partilojal, men konsentrerte seg vesentlig om næringsspørsmål,
særlig skipsfarten.23 Henschien var født ved Grimstad, men vokste opp på Nedre Rome
rike.24 Han dro tidlig til sjøs, og ble skipsfører allerede som 22-åring. Gjennom ekteskap med Christophila Henrikke Arentz i 1867 fikk han
innpass i en familie med røtter tilbake til fornemme, gamle lillesands
slekter – Jusnæss og Steenersen. I 1878 gikk Henschien i land for godt og slo seg ned på Lofthus i Vestre
Moland, like nord for Lillesand. Han arvet en ikke ubetydelig sum pen-
ger, og investerte både i skipsrederi og skipsverft. Men dårlige konjunk-
turer førte etter en tid til stans i skipsbyggingen. I Vestre Moland fikk 86 hva var det med lillesand? Henschien mange verv og oppgaver.25 Etter 12 år som ordfører frasa han
seg gjenvalg i 1887. På Stortinget var Henschien i begge periodene medlem av nærings
komite nr. 2, og ble valgt til sekretær i denne komiteen i 1895. Han ble
også medlem av Lagtinget i 1895. Men 28. august samme år døde han,
bare 58 år gammel. I nekrologen i Lillesands Tilskuer blir han blant annet
omtalt slik som ordfører: Det kan vel trygt siges, at Vestre Moland aldrig har havt en saa dyktig Ord
fører. Han havde en levende Interesse for Kommunens Vel, var Ordensmand i
høi Grad, saa at intet glemtes eller forsømtes.26 26
Lillesands Tilskuer 5.9.1895. Følgende sitat: samme referanse. 29
Lillesands Tidende 1.10.1891. Årgangene 1887–92 for Lillesands-Posten har ikke latt seg oppspore. 28
Lillesands Tilskuer 10.11.1891. Som stortingsmann fikk han dette skussmålet: Man vilde [i 1891] have en dygtig Repræsentant for Amtets vig-
tige Næringskilde, Skibsfarten, og i denne Henseende indtog
Henschien en meget fremskudt Stilling. Han havde sluttet sig
til det moderate Parti, men sto forresten Høire-partiet meget
nær. Nogen egentlig Politiker var Henschien ikke. Han gav
sig saaledes aldrig af med at holde politiske Taler under Valg
tiden f.ex., og i Thinget kastede han sig sjelden ind i Debatten;
men han havde et fornuftigt Skjøn paa Sagerne og lod sig ikke
let paavirke ved Agitation. I Sager vedkommende Søvæsenet
øvede han adskillig Indflydelse. J.A. Henschien (1836–95). Foto: Stortingsarkivet. 64 valgmenn møtte i distriktsforsamlingen i Arendal lør-
dag 21. november 1891 for å velge stortingsrepresentanter fra
landdistriktene og ladestedene i Nedenes amt for perioden
1892–94. J. A. Henschien ble valgt som den fjerde og siste, i
tillegg til tre høyrerepresentanter.27 J.A. Henschien (1836–95). Foto: Stortingsarkivet. 87 kapittel 4 kapittel 4 I valgkampen høsten 1891 var ikke Henschiens kandidatur gjenstand
for noen omfattende diskusjon i pressen. Det kan se ut som om han
først seilte opp som offisiell kandidat et par uker før distriktsforsamlin-
gen i Arendal, da den konservative siden 5. november holdt prøvevalg
på valgmenn i Lillesand og Vestre Moland. Hotel Norges nye festsal ble
tatt i bruk til dette formålet, og flere enn noen gang tidligere ved en slik
anledning hadde møtt fram. Det var stor enighet om et kompromiss mel-
lom den nystiftede Lillesands og Omegns moderate Venstreforening og
Høyre, som hadde sammenfallende synspunkter i de store rikspolitiske
sakene. De to fraksjonene fikk to valgmenn hver, og den ene av de mode-
rate var Henschien.28 Var sjøfolk mindre egnet som politikere enn bønder? Dette spørsmålet
var gjenstand for en viss diskusjon forut for valget. I et anonymt innlegg
i Lillesands Tidende 1. oktober 1891 stilte signaturen «T.» seg sterkt kritisk
til et leserinnlegg i Kristianssands Stiftsavis, som hadde tatt til orde for at
«Nedenæs – Kyststrøget – er langt bedre tjent med en dygtig Mand fra
Sætersdal, end en middelmaadig fra sit eget Distrikt».29 Det som særlig
stakk, var det underforståtte, nemlig at de middelmådige var sjøfolk, og at
«Sjøfolk ikke forstaar sig paa Politik». Å oppstille «omtrent udelukkende
Bønder» som representanter for Nedenes, «hvis fornemste Interesse og
Livsnerve er Søfarten», oste av «overtro» og fordommer, mente «T.», og
fortsatte: Man er ikke et dummere Folkefærd langs Kysten, fordi man der har havt
Adgang til bedre Skolegang, og har faaet et lidet Pust fra det Liv, som pulserer
udi den store Verden, og det er ikke den ufeilbarlige Betingelse for politisk
Kløgt, at han har levet de bedste Aar af sit Liv i en Fjeldbygd, der væsentlig har
suget sin politiske Næring af idelig Avislæsning. Men at det kunne være vanskelig for en sjømann å følge med i riks
politikken, var noe J. A. Henschien selv hadde innrømmet noen år tidli-
gere. Da han møtte som valgmann til det forberedende møtet i Arendal 88 hva var det med lillesand? i forbindelse med stortingsvalget høsten 1879, året etter at han var gått i
land for godt, ble han bedt om å redegjøre for sine standpunkter. Hans
svar, slik de ble gjengitt i lokalavisen, tydet ikke på vesentlig innsikt i
tidens store politiske stridsspørsmål. På generelt grunnlag sa han seg enig
med de eldre «Landrepræsentanter» i de store spørsmålene. 30
Lillesands-Posten 8.1.1880. (Referat fra Agderposten.) Ved dette valget fikk Henschien bare få
valgmannsstemmer. I representant-valget fikk han én stemme, og i suppleant-valget 5 stemmer.
Lindstøl 1914c: 422. 31
Den vestlandske Tidende 20.11.1891, leserinnlegg datert 17.11. kapittel 4 Statsråds
saken, derimot, «maatte han sige, han ikke forstod; men han kunne
maaske lære at forstaa den». Hovedårsaken til hans manglende kjennskap
til de politiske sakene som hadde vært på agendaen i årene forut, var at
han i flere år hadde seilt til sjøs, fortalte han, og da brydde han seg verken
om «Storthing eller Kommune og var aldeles uvidende om slige Ting».30
Men et visst kjennskap til kommunepolitikk hadde han allerede fått, og
ytterligere erfaring – både på lokal- og riksplan – skulle han få i fullt
monn de kommende årene. Dagen før valget i 1891, 20. november, fikk Henschien en svært posi-
tiv omtale av en lillesander i den konservative arendalsavisen Den vest
landske Tidende: Som større skibsreder og indsigtsfuld mand i søvæsenet i det hele taget har
man i hr. Johannes Henschien i Lillesand. Opmærksomheden bør ganske vist
rettes paa ham som en der paa en værdig saavelsom dygtig maade vil kunne
repræsentere amtet. Den anonyme lillesanderen framhevet at Henschien hadde røktet sine
verv i kommunen «med sjelden stor dygtighed», at han var «i besiddelse
af grundige kundskaber – har sproget i sin magt baade at skrive og tale
sikkert og let for sig» og at han var «af et nobelt Karakter og en meget
dannet mand i sin bedste manddomsalder». Det ville være vanskelig å
finne en annen tilsvarende dyktig tingmann.31 Men så våknet anonyme «X», åpenbart bosatt et stykke øst for Lille-
sand. På selve valgdagen fikk han – for det var høyst sannsynlig en mann
– inn en liten meningsytring i arendalsavisen. Han konstaterte at alle 89 kapittel 4 var enige om at Nedenes amt burde være godt representert av skipsfarts
interesserte menn. Lillesand og Vestre Moland unte han riktig nok en
representant, «men mere end en heller ikke». Selv om det blant de fire
valgmennene fra Vestre Moland (inklusive Lillesand) var to skipsredere –
Gerh. Krog foruten Henschien – burde bare Henschien komme i betrakt-
ning, framholdt han. «X» ønsket nemlig også dyktige skipsredere med
interesse for stortingsvervet fra den østlige delen av amtet.32 Med andre
ord: En viss geografisk balanse ble her tillagt stor vekt. Sjøfolks egnethet som politikere kom også opp i valgkampen høsten
1894. Den var som tidligere preget av stor avstand mellom høyre- og
venstresiden. Unionspolitikken, som var høyt oppe på agendaen, splittet. 32
Den vestlandske Tidende 21.11.1891, leserinnlegg. 34
Disse representerte Nedenes amt på Stortinget 1895– 97 i tillegg til J. A. Henschien og hans vara-
mann, C. S. Aasen: Kasserer Jakob Aall Bonnevie (H), gårdbruker Ole Eriksen Grændsen (H) og
gårdbruker Nils Pedersen Igland (H). Lindstøl 1915: 525. 33
Lillesands Tilskuer 25.10.1894. 32
Den vestlandske Tidende 21.11.1891, leserinnlegg.
33
Lillesands Tilskuer 25.10.1894.
34
Disse representerte Nedenes amt på Stortinget 1895– 97 i tillegg til J. A. Henschien og hans vara-
mann, C. S. Aasen: Kasserer Jakob Aall Bonnevie (H), gårdbruker Ole Eriksen Grændsen (H) og
gårdbruker Nils Pedersen Igland (H). Lindstøl 1915: 525. kapittel 4 I Nedenes amt var det nå som før viktig for mange at sjøfartens interes-
ser var representert på tinget. Men «hvis radikalerne seirer», advarte
Lillesands Tilskuer i slutten av oktober, ville det ikke bli tatt stort hen-
syn til «Sjøfolkene og deres Interesser». Grunnen var ifølge den konser-
vative avisen at «efter Radikalernes Sigende forstaar Sjøfolkene sig ikke
det Gran paa Politik. Sjøfolkene kan være gode at have med til at betale
Skatter; men til at have nogen Mening i Politiken - -, Nei, der faar de staa
tilbage for forhenværende Statsraader og Kirkesangere!»33 Da valgforsamlingen kom sammen i Arendal 22. november 1894 for
å velge stortingsrepresentanter for perioden 1895–97, tilhørte 48 av de
78 valgmennene i Nedenes amt Høyre og Moderate Venstre i valgsam
arbeid, og 30 Venstre. I likhet med tre år tidligere fikk høyresiden samt-
lige representanter. J. A. Henschien, som nå stilte for partiet Centrum,
ble innvalgt som andre representant fra Nedenes amt, mens de tre øvrige
representerte Høyre.34 Men som nevnt døde Henschien i august 1895, og
første varamann, handelsfullmektig C. S. Aasen, rykket inn. Det endte
derfor med at ingen av representantene fra bygdene i Nedenes amt kom
til å representere sjøfarten i denne perioden. De øvrige var en kasserer og
to gårdbrukere. Sjøfarten var i ferd med å forsvinne som amtets viktigste 90 hva var det med lillesand? næring, og det samme var stortingsrepresentantene som representerte
næringen. I det følgende tiåret, 1896–1906, kom ingen stortingsrepresentanter fra
Lillesand, Vestre Moland eller Høvåg.35 Da den tredje stortingsrepresen-
tanten fra Lillesand gjorde sitt inntog på den rikspolitiske arenaen i 1907,
var det helt andre saker som stod på den politiske agendaen. Nå var det
definitivt ikke skipsfarten som stod i fremste rekke. 35
I stortingsvalget i 1897 stilte skipsreder T. A. Birknes fra Vestre Moland for Venstre. Han ble
valgt som 3. varamann fra Nedenes amt. Samtlige fire stortingsrepresentanter fra amtet tilhørte
partiet Venstre. Men Birknes møtte ikke på Stortinget i denne perioden, 1898–1900. Heller ikke
i neste stortingsperiode, 1900–03 (med stortingsvalg 1900) kom han på Stortinget. Da var han
4. varamann for Venstre (som også denne perioden hadde samtlige fire representanter fra
Nedenes amt). Lindstøl 1915: 548; 569–70.
36
Lillesands Tilskuer 10.12.1908, redaksjonelt under overskriften «Lillesands Diktator», i forbin
delse med valg av to medlemmer til skolestyret. 36
Lillesands Tilskuer 10.12.1908, redaksjonelt under overskriften «Lillesands Diktator», i forbin
delse med valg av to medlemmer til skolestyret. p
jt
38
Bjørnstad 1949: 61. Ved stortingsvalget i oktober 1918 for perioden 1919–21 ble gårdbruker T.
Aamlid (V) fra Birkenes valgt med lensmann B. Kleveland (V) fra Høvåg som varamann. De
vant første valgomgang med henholdsvis 1508 og 1892 stemmer. I omvalget vant de med 2063 og
2075 stemmer. Kleveland møtte ikke på Stortinget i denne perioden. Disponent G. A. Vennes
land fra Vestre Moland stilte også til valg med gårdbruker P. K. Grevstad som varamann for
Høyre og Frisinnede Venstre. I første valgomgang fikk de henholdsvis 1252 og 1253 stemmer. De
gikk videre til omvalget, og fikk 1759 og 1754 stemmer, men ble altså slått av venstrekandidatene
Aamlid og Kleveland. N. Chr. Gauslaa
– «Lillesands almægtige Diktator» Noan Christian Gauslaa må kunne karakteriseres som den største stor-
tingspolitikeren Lillesand har hatt. Han var lærer og skolebestyrer, utgi-
ver og redaktør av Lillesands-Posten, industridrivende og
bankmann, kommune- og stortingspolitiker. Ikke minst
som redaktør (fra 1902) og ordfører (fra 1907) satt han med
«bukta og begge endene». Av den konkurrerende høyre
avisen Lillesands Tilskuer ble han i 1908 omtalt som «Lille-
sands almægtige Diktator».36 Noan Chr. Gauslaa (1864–1952). Maleri i Lillesand rådhus. Eier:
Lillesand kommune. Foto: Roald
Hermansen. Noan Chr. Gauslaa (1864–1952). Maleri i Lillesand rådhus. Eier:
Lillesand kommune. Foto: Roald
Hermansen. Han var sønn av smed og skipsreder Nils Christian
Sørensen Gauslaa og Gusta Govertsdatter f. Tellefsen og gift
med rederdatteren Martha Maria f. Terjesen (1864–1934). Noe som kan ha hatt en viss betydning for hans samfunns
engasjement og politiske ståsted, var at han var sønne-
sønns sønn av lofthusmannen Halvor Kittelsen Gauslaa fra
Herefoss. Noan Chr. Gauslaa (1864–1952). Maleri i Lillesand rådhus. Eier:
Lillesand kommune. Foto: Roald
Hermansen. N. Chr. Gauslaa fikk en solid utdannelse og hadde i
oppveksten god støtte av sin far, som gjennom flere tiår 91 kapittel 4 var engasjert i kommunale saker og også var ordfører (1888 og 1895). I 1882 begynte han å studere språk og historie ved Maribogadens skole
i Kristiania, og i 1891 tok han lærereksamen og ble cand.philol. I årene
1886–1900 var han lærer flere steder, før han i januar 1901 ble bestyrer
(adjunkt, overlærer og lektor) ved det som da het Lillesand kommunale
høiere almenskole (Middelskolen). Den stillingen hadde han i nærmere
35 år, til august 1935. I Lillesand bystyre ble han for første gang innvalgt i 1905, og fra 1907
var han ordfører sammenhengende i 30 år for partiet Venstre. I tillegg
hadde han flere andre verv.37 Gauslaa representerte partiet Venstre på Stortinget, valgt fra Sand krets
i Nedenes amt 1907–09, 1913–15 og 1916–18. Han møtte også på det over
ordentlige (ekstraordinære) Stortinget i 1918. I den første perioden var han
medlem av næringskomite nr. 2. I den andre perioden var han medlem av
næringskomite nr. 1, i den tredje perioden nestformann i denne komiteen
og 1913–18 sekretær i Odelstinget. Gauslaa var aktiv i avholdsbevegelsen i
Lillesand, og var også formann i Stortingets avholdsgruppe 1913–15. Hele
54 av de 123 stortingsrepresentantene var medlemmer av denne gruppen
i Gauslaas formannsperiode. g
39
Ved lov av 14. august 1918 ble inndelingsbetegnelsen «amt» endret til «fylke». 37
N. Chr. Gauslaa var blant annet skolestyreformann (1904–06), ordfører i forstanderskapet
og formann i kontrollnemnda i Lillesands Sparebank (fra 1903), formann i direksjonen for
Lillesand–Flaksvatnbanen (1906–07 og 1913–47) og formann i Kokkenes Brug (fra 1917). I 1927
skrev han sparebankens 75-års jubileumsskrift. 40
Torjus Værland (1868–1954) fra Vegårshei ble valgt til stortingsrepresentant sammenhengende
i fem perioder 1919–33. Gauslaa møtte siste gang som varamann for Værland da han ble sosial
minister i Mowinckels andre regjering 1928–31. Torjus Værland, Wikipedia.i N. Chr. Gauslaa
– «Lillesands almægtige Diktator» I stortingsperioden 1919–21 var Gauslaa ute av rikspolitikken.38 Men fra
1922 var han i fire stortingsperioder (1922–24, 1925–27, 1928–30 og 1931–33)
varamann for Aust-Agder fylke, som tidligere Nedenes amt nå het.39 Han
møtte da flere ganger på Stortinget for representanten Torjus Værland 92 hva var det med lillesand? (Venstre) fra Vegårshei: I 1922, 1923, 1924, 1928–30 og i 1931.40 I disse årene
var han medlem av lønningskomiteen (1923, 1924), utenriks- og konsti-
tusjonskomiteen (1928–30 og 1931), den forberedende fullmaktskomiteen
(1930) og Lagtinget (1928–30 og 1931). Da lærer Aanund Tveit portretterte Gauslaa i Fylkingen i 1938, siterte
han en høyremann: «Han ligger som en død manet over byen og kveler
dens utvikling.» For «Gauslaa og Lillesands bystyre har ofte – kanskje
oftest – vært det samme», fortsatte han. Dessuten eide han lokalavisen. «Jeg har min avis», kunne Gauslaa si, og der kom hans og Venstres menin-
ger tydelig fram – ikke minst i avholdssaken, som stod i fremste rekke på
den politiske agendaen, både lokalt og nasjonalt. Men selv om mange var
uenig med ham og mislikte hans kampmetoder og den «faderlige, belæ-
rende tonen», var hans dominerende stilling også med på å skape ro og
fasthet. «Gauslaa-perioden» var enestående i Lillesand.41 Da N. Chr. Gauslaa ble portrettert og intervjuet av Birger Gauslaa i
Lillesands-Posten i forbindelse med 75-års dagen 11. oktober 1939, ble hans
«dimensjoner, virkefelt og arbeidskraft» kommentert slik: Det synes reint ufattelig at han har kunnet overkommet det alt, og det – vel
å merke – på den grundige og samvittighetsfulle måte som er egen for ham. Men han har overkommet det, og han sitter ennå i dag inne med en sjelden
arbeidskraft – tross sine 75 år.42 gj
g 9
3
j
,
p
41
Fylkingen 11.2.1938, «Sørlandsprofiler», kopi i Kjell Rosenbergs privatarkiv, Lillesand kommune. 41
Fylkingen 11.2.1938, «Sørlandsprofiler», kopi i Kjell Rosenbergs privatarkiv, Lillesand kommune.
42
Lillesands-Posten 10.10.1939. y
g
pi
p
j
g p
42
Lillesands-Posten 10.10.1939. y
g
42
Lillesands-Posten 10.10.1939. 43
Christian Michelsens borgerlige samlingsregjering – en koalisjon av deler av Venstre, Høyre,
Moderate Venstre og Samlingspartiet – tiltrådte 11.3.1905. Den avløste Francis Hagerups regje
ring, som var en koalisjon av Samlingspartiet (Høyre og moderate krefter fra Venstre), Venstre
og Høyre. Christian Michelsens regjering, Lokalhistoriewiki. Han døde i 1952, 88 år gammel. Vi skal først stoppe opp ved stortingsvalget høsten 1906, da Gauslaa for
første gang ble valgt. Dette stortingsvalget var det første etter at unionen
med Sverige var oppløst. De spørsmålene som helt siden begynnelsen av
1890-årene hadde skilt partiene fra hverandre og skapt store stridigheter,
var dermed falt bort. Det førte til endrede og til dels uklare partigren-
ser. Mange velgere så vel som ledende politikere – særlig på høyresiden, 93 kapittel 4 men også på venstresiden – ville beholde Christian Michelsens borgerlige
samlingsregjering.43 I 1906 foregikk valget i Nedenes amt for første gang direkte og kretsvis. Sand krets – en av de fire kretsene i Nedenes amt – bestod av herredene
Herefoss, Fjære, Landvik, Eide og Birkenes, foruten Vestre Moland,
Høvåg og ladestedet Lillesand. Valgordningen med direkte valg i enmannskretser fungerte slik at
dersom ingen av kandidatene som stilte til valg oppnådde absolutt fler-
tall (mer enn 50 prosent av stemmene), ble det holdt en ny valgomgang
(omvalg). Nå var det tilstrekkelig med simpelt flertall. Den nye valg
ordningen la opp til politisk polarisering, favoriserte de store partiene
og innbød til valgsamarbeid. Men i Nedenes amt var partikonstellasjo-
nene ganske oversiktlige, med to konkurrerende partier: Samlingspartiet
(Høyre, Moderate Venstre og Frisinnede Venstre) og Venstre. På denne tiden var det flere enkeltspørsmål, sakskomplekser og sær-
interesser som for mange veide tyngre enn spørsmålet om høyre eller
venstre. De viktigste var jernbanespørsmål, avholdssak, kirkelig strid,
konsesjonslovene (hjemfallsretten), interessene til bøndene og bygdene
(fra 1896 organisatorisk samlet i Norsk Landmandsforbund) samt mål-
saken. Gauslaa, som tilhørte det som gjerne ble kalt «kjernevenstre» eller
«det rene Venstre», var opptatt av de sentrale venstresakene, ikke minst
avholdssaken. I 1906 ble Gauslaa – den 42 år gamle bymannen, avholdsmannen,
skolebestyreren, avismannen og ordføreren – valgets vinner, selv om han
verken var målmann eller tilhørte gårdbrukerstanden. Det ser heller ikke
ut til å ha talt synderlig til hans ugunst at han kom fra den vestre delen
av Sand krets, selv om enkelte brukte dette som et argument mot ham. Avholdssaken var høyt oppe på den politiske agendaen på denne tiden,
og kan ha hatt avgjørende innvirkning på valgutfallet. «Totalfolkets»
landsmøte hadde nemlig vedtatt at ingen stortingskandidater kunne få 94 hva var det med lillesand? stemmer fra deres medlemmer med mindre de klart og bindende aksep-
terte samtlige av deres programposter. 45
Lindstøl 1915: 625–26; Stortingsvalget 1906, Wikipedia. Foruten Gauslaa satt disse på Stortinget
fra Nedenes Amt i stortingsperioden 1907–09: gårdbruker Peder Tjøstolfsen Aas (Samlingspar-
tiet, valgt fra Holt krets), gårdbruker Finn Blakstad (Samlingspartiet, valgt fra Nedenes krets)
og forhenværende statsråd Lars Knutson Liestøl (Venstre, valgt fra Setesdal krets). Statsminister
Christian Michelsens borgerlige samlingsregjering gikk av 23. oktober 1907. Jørgen Løvland (V)
ble statsminister (samtidig som han fortsatte som utenriksminister) for en samlingsregjering,
som satt fram til 19. mars 1908. I 1908 dannet Gunnar Knudsen en mindretallsregjering med
støtte fra De forenede norske Arbeidersamfund. Denne venstreregjeringen satt fram til 2. febru-
ar 1910. 44
Tvedt 2017. I tillegg til Venstre og Samlingspartiet ble Sosialdemokratene (10 representanter) og
Radikale folkeparti (4 representanter) valgt inn på Stortinget i 1906. Mandatfordelingen endret
seg noe i stortingsperioden. Han døde i 1952, 88 år gammel. Før stortingsvalget i 1906 ble de konservative kandidatene og deres
varamenn i Sand krets spurt av «Totalisternes kredsnevnd i Sands valg-
kreds» ved formann Torjus Hanssen om «deres stilling til afholdsfolkets
program». Venstrekandidatene N. Chr. Gauslaa og Knud T. Aamlid var
det ikke nødvendig å spørre – de var begge profilerte totalavholdsfolk. Prost Karl Kobro ville som stortingsrepresentant strekke seg langt for
å få bukt med «drikkeondet», bedyret han. Men han hadde likevel reser-
vasjoner mot enkelte av postene på totalistenes valgprogram, og konklu-
derte slik: «Idet jeg saaledes reserverer mig […], vil jeg tilføie, at dersom
afholdsfolket derfor unddrager mig sin stemme, faar de saa gjøre.» Ben-
dix K. Imenæs var totalavholdsmann, og kunne derfor uforbeholdent si
seg enig i og tiltre avholdsfolkets valgprogram. Gauslaa og Kobro gikk videre til omvalget i 1906, og totalavholdsman-
nen Gauslaa ble som nevnt valgets vinner. På nasjonalt nivå fikk Ven-
stre 73 av de 123 stortingsmandatene, og dermed et overveldende flertall
(59 prosent).44 To av de fire fra landdistriktene i Nedenes amt som var
på Stortinget i perioden 1907–09, representerte Venstre, og de to andre
Samlingspartiet.45 Vi skal også stoppe opp ved stortingsvalget høsten 1909 (for perioden
1910–12). Ved dette valget fikk Høyre og Frisinnede Venstre til sammen
rent flertall på Stortinget med 65 av de 123 representantene, mens Venstre 95 kapittel 4 stod tilbake med 45 og Sosialdemokratene med 11 represen-
tanter.46 I Nedenes amt hadde også Høyre og Frisinnede
Venstre framgang og Venstre tilbakegang ved dette valget. Likevel gikk mandatet i to av kretsene, Holt og Setesdal, til
Venstre. Høyre kapret derimot mandatet i Nedenes krets.47 Hans Thorvald Hansen (1854–
1931). Eier: Forfatteren. Foto: Roald Hermansen. Hvordan gikk det i Sand krets? Her var to representanter
fra Lillesand å finne: N. Chr. Gauslaa, som stilte til gjen-
valg for Venstre, og skipsreder Hans Thorvald Hansen, som
stilte for Frisinnede Venstre for første gang. I første valg
omgang fikk Gauslaa flest stemmer, med høyrekandidaten
Bendix K. Imenæs fra Landvik på andreplass. I omvalget
vant derimot Imenæs med Hansen som varamann. Som
tidligere nevnt møtte Hansen på Stortinget i 1911 og 1912
under Imenæs’ sykdom. Hans Thorvald Hansen (1854–
1931). Eier: Forfatteren. Foto: Roald Hermansen. Vi skal i det følgende se nærmere på velgeroppslutningen
og -atferden i Sand krets ved valget i 1909. Som vi har sett,
ble Gauslaa valgt til stortingsrepresentant for perioden før, 1907–09. 46
Liste over Norges regjeringer, Wikipedia; Tvedt 2017, 2019. I tillegg til Venstre, Høyre og Frisin-
nede venstre ble Sosialdemokratene (11 representanter) og Radikale folkeparti (2 representanter)
valgt inn på Stortinget i 1909. Gunnar Knudsens regjering søkte avskjed og gikk av i februar 1910,
og ble erstattet av Wollert Konows samarbeidsregjering mellom Høyre og Frisinnede Venstre.
Da den gikk av i februar 1912, ble den erstattet av Jens Bratlies samarbeidsregjering, som støttet
seg på de samme partiene. Denne regjeringen gikk av i slutten av januar 1913. 48
Kvinnenes stemmerett ved stortingvalget i 1909 var begrenset: Den gjaldt nemlig bare kvin-
ner som hadde fylt 25 år og som betalte skatt av en inntekt på minst kr. 300 på landet eller
kr. 400 i byene, eller som levde i formuesfellesskap med en mann som betalte skatt. Kvinner som
oppfylte disse betingelsene hadde hatt stemmerett ved kommunevalgene fra 1901. Fra og med
stortingsvalget i 1915 (vedtatt i 1913) hadde kvinner over 25 år alminnelig stemmerett på lik linje
med menn. Søbye & Dørum 2020. 46
Liste over Norges regjeringer, Wikipedia; Tvedt 2017, 2019. I tillegg til Venstre, Høyre og Frisin-
nede venstre ble Sosialdemokratene (11 representanter) og Radikale folkeparti (2 representanter)
valgt inn på Stortinget i 1909. Gunnar Knudsens regjering søkte avskjed og gikk av i februar 1910,
og ble erstattet av Wollert Konows samarbeidsregjering mellom Høyre og Frisinnede Venstre.
Da den gikk av i februar 1912, ble den erstattet av Jens Bratlies samarbeidsregjering, som støttet
seg på de samme partiene. Denne regjeringen gikk av i slutten av januar 1913.
47
Foruten Bendix Karelius Imenæs (Høyre, valgt fra Sand krets) satt disse på Stortinget fra Nede-
nes amt i stortingsperioden 1910–12: lærer og lensmann Tallak Olsen Lindstøl (Venstre, valgt
fra Holt krets), gårdbruker Finn Blakstad (Høyre, valgt fra Nedenes krets) og forhenværende
statsråd Lars Knutson Liestøl (Venstre, valgt fra Setesdal krets).
48
Kvinnenes stemmerett ved stortingvalget i 1909 var begrenset: Den gjaldt nemlig bare kvin-
ner som hadde fylt 25 år og som betalte skatt av en inntekt på minst kr. 300 på landet eller
kr. 400 i byene, eller som levde i formuesfellesskap med en mann som betalte skatt. Kvinner som
oppfylte disse betingelsene hadde hatt stemmerett ved kommunevalgene fra 1901. Fra og med
stortingsvalget i 1915 (vedtatt i 1913) hadde kvinner over 25 år alminnelig stemmerett på lik linje
med menn. Søbye & Dørum 2020. 47
Foruten Bendix Karelius Imenæs (Høyre, valgt fra Sand krets) satt disse på Stortinget fra Nede-
nes amt i stortingsperioden 1910–12: lærer og lensmann Tallak Olsen Lindstøl (Venstre, valgt
fra Holt krets), gårdbruker Finn Blakstad (Høyre, valgt fra Nedenes krets) og forhenværende
statsråd Lars Knutson Liestøl (Venstre, valgt fra Setesdal krets). Hans Thorvald Hansen (1854–
1931). Eier: Forfatteren.
Foto: Roald Hermansen. 49
Larsen & Øksendal 2013: 564. Artikkelen ble i 2014 tildelt «HT-prisen» av Den norske historiske
forening (HIFO) for mest nyskapende bidrag til Historisk tidsskrift i 2013.
50
Folketellingen 1910. Folketallet i Lillesand gikk tilbake fra 1508 i 1891 til 1239 i 1910. Kvinneande-
len var begge årene 57 %. I 1910 bodde det 705 kvinner og 534 menn i Lillesand.
51
Høegh-Omdal 1977: 85. På følgende side er også en interessent analyse av valgatferden i Vestre
Moland. Blant annet kopler hun mennenes svikt i frammøte i til Imenæs’ manglende appell.
52
Larsen & Øksendal 2013: 579 52
Larsen & Øksendal 2013: 579 g
52
Larsen & Øksendal 2013: 579 Han døde i 1952, 88 år gammel. Han
ble også valgt for de to etterfølgende periodene, 1913–15 og 1916–18, men
altså ikke for 1910–12. Spørsmålene blir derfor: Hvorfor vant Høyre val-
get i 1909? Hvorfor nådde ikke venstremannen Gauslaa opp? Kan utfal-
let knyttes til det faktum at norske kvinner ved dette stortingsvalget for
første gang hadde stemmerett?48 Kan årsaken ha vært at kvinnene mobili
serte og stemte annerledes – dvs. mer konservativt – enn mennene? en. sen. Foto: Roald Hermansen. 96 hva var det med lillesand? I sin prisbelønte artikkel «De glemte kvinnevalgene» konstaterer
historikerne Eirinn Larsen og Lars Fredrik Øksendal at dette valget var
det store gjennombruddet for norske kvinner som politisk ressurs. Utfal-
let av valget – seieren til Høyre og Frisinnede Venstre – kan etter deres
oppfatning direkte forklares med kvinnestemmene. 49 Men hvordan og
hvorfor stemte kvinnene annerledes enn mennene? Og hvordan utgjorde
kvinnene en forskjell i Sand krets? Når det gjelder valgdeltakelsen i Sand krets, er det første vi kan merke
oss at den nå som før var vesentlig høyere i ladestedet Lillesand enn
på bygdene rundt. Når det gjelder kvinnenes valgdeltakelse, var også
den høyest i Lillesand. Et oppsiktsvekkende trekk er at prosentandelen
stemmeberettigede kvinner som stemte, var høyere enn for mennene. Dette slo særlig sterkt ut på grunn av et spesielt demografisk trekk. Det
var nemlig – vesentlig på grunn av krisen i skipsfarten med påfølgende
utflytting – langt flere kvinner enn menn hjemmehørende i Lillesand på
denne tiden.50 Hvorfor var kvinnenes valgdeltakelse spesielt høy i Lillesand? I hoved-
oppgaven om stortingsvalget i Nedenes amt 1909 skriver Arna Unander
Høegh-Omdal at dette «er ikke lett å si». Men samtidig antyder hun at
det særlig hadde med de to kandidatene fra Lillesand som stilte i første
valgomgang, nemlig N. Chr. Gauslaa og Hans Thorvald Hansen, å gjøre. Det var spesielt Hansen som profitterte på kvinnemobiliseringen. Det var
stor aktivitet blant såkalt bedrestilte kvinner i Lillesand og Vestre Moland
på den tiden.51 I omvalget stod kampen mellom Gauslaa og Imenæs. Nå skjedde en
enda sterkere kvinnemobilisering enn i første valgomgang, et trekk som
forøvrig kan registreres over hele landet.52 Antall avlagte kvinnestemmer
i Sand krets ble nesten fordoblet. 53
Larsen & Øksendal 2013: 574–75
54
Larsen & Øksendal 2013: 588
55
Larsen & Øksendal 2013: 582 Han døde i 1952, 88 år gammel. 97 kapittel 4 Et helt fundamentalt poeng er at velgerne – i dag som i 1909, og kvinner
så vel som menn – bruker sin stemmerett når valget oppfattes som vik-
tig.53 Velgerne i Sand krets må ha oppfattet valget, og da særlig omvalget,
som spesielt viktig. Og mobiliseringen var kraftig i Lillesand, der både
N. Chr. Gauslaa og Hans Thorvald Hansen var hjemmehørende. I Lille-
sand stemte hele 84 prosent av de stemmeberettigede kvinnene, men bare
67 prosent av mennene ved omvalget. Gauslaa tapte altså valget. Og det synes temmelig klart at de 1090
kvinnestemmene i Sand krets avgjorde valget i konservativ retning. Min
næranalyse av valget støtter konklusjonene til Larsen og Øksendal, som i
artikkelen om «de glemte kvinnevalgene» klart og entydig konkluderer at
mandatet ville blitt tatt av Venstre uten kvinnestemmene.54 Høyst sann-
synlig ville Gauslaa ha kapret stortingsplassen dersom ikke kvinnene
hadde hatt stemmerett, eller dersom de ikke hadde mobilisert så kraftig
ved dette valget. Det gjaldt å ha kvinnetekke, noe Gauslaa åpenbart ikke
hadde i like stor grad som sin motkandidat! Men det var ikke bare i Sand krets at valgutfallet sannsynligvis ville
blitt et annet uten kvinnestemmene. Larsen og Øksendal konkluderer
også med at Høyre og Frisinnede Venstre totalt ville ha tapt 18 mandater
dersom bare menn hadde fått stemme i 1909. Det konservative stortings-
flertallet ville dermed gått tapt, og Wollert Konow hadde ikke kunnet
danne regjering.55 Så viktige var kvinnestemmene i 1909.l I 1912 kom Gauslaa tilbake på Stortinget. Han ble valgt med rent fler-
tall i Sand krets, og det var derfor ikke nødvendig med omvalg. Stor-
tingsvalget i oktober 1915 (for perioden 1916–18 samt det overordentlige,
ekstraordinære storting i 1918) var siste gang Gauslaa ble valgt som fast
representant til Stortinget, denne gangen ved omvalg. Dette valget var
det første der kvinner hadde allmenn stemmerett på lik linje med menn. Nå utgjorde kvinnene et flertall av velgerne i Lillesand og Vestre Moland,
men ikke i Høvåg. I Lillesand var kvinneoverskuddet i befolkningen som
nevnt betydelig på denne tiden. Men Gauslaas sterke oppslutning tyder 98 hva var det med lillesand? ikke på at kvinnene der i vesentlig grad stemte annerledes – dvs. mer
konservativt – enn mennene ved dette valget. Da stortingsvalget ble avholdt 21. oktober 1918, bare få uker før første
verdenskrig ble avsluttet, stilte ikke N. Chr. Gauslaa til gjenvalg. Han døde i 1952, 88 år gammel. Han
hadde stilt til valg ved samtlige fem stortingsvalg fra 1903 til og med 1915,
og hadde sittet på Stortinget i tre av de fem periodene, i til sammen ni år. Men nå var han ute av rikspolitikken – enn så lenge. Han kom nemlig
tilbake. I årene 1922–31 var han sammenhengende vararepresentant for
Aust-Agder fylke, og møtte i lange perioder på tinget. Oppsummering I perioden 1862–1918 kom, som vi har sett, fire menn fra Lillesandsområ-
det på Stortinget: Jacob Svendsen, J. A. Henschien, Hans Thorvald Han-
sen og N. Chr. Gauslaa. Oppmerksomheten har vært konsentrert rundt
de tre som satt lengst: Svendsen, Henschien og Gauslaa. Avslutningsvis
skal vi peke på noen sentrale kriterier for å bli valgt og vraket. Stortingsvalgene ble raskt og tydelig politiserte fra slutten av 1860-
årene, og det ble etablert en tydelig venstre- og høyreside på Stortinget. Dette ga seg også regionale utslag. Ett parti eller én partikonstellasjon
gjorde flere ganger rent bord. Men ennå i flere år var også bosted og
næring viktige kriterier for valg av representanter, særlig dimensjonene
kyst–innland, by–bygd og maritime næringer i forhold til jord- og skog-
bruksinteresser. Fram til forrige århundreskifte mente mange at det var
svært viktig at skipsfarten var representert på Stortinget. Men etter at den
forsvant som amtets viktigste næring, forsvant også stortingsrepresen-
tantene som representerte den. Selvfølgelig spilte personlige egenskaper inn. Alle de fire stortings
representantene fra vårt område var også engasjert i lokalpolitikken, til
dels i lange perioder og i mange ulike verv. To av dem hadde «politikken
i blodet» – Henschiens far hadde vært stortingsmann, og Gauslaas far
hadde vært ordfører. Både Svendsen, Henschien og Gauslaa var ordførere og ble gjenvalgt
flere ganger, noe som er uttrykk for en enestående posisjon i lokalsam-
funnet. Men det skal likevel ikke forstås som om de hadde allmenn 99 kapittel 4 oppslutning. Til det var de politiske motsetningene for store. Samtidig
var det slik at rikspolitiske motsetninger ikke alltid, og til alle tider, ga seg
direkte utslag i lokalpolitikken. Ledende rikspolitikere kunne være split-
tende ved stortingsvalg, men samtidig samlende lokalt. Uansett hadde de
stor innflytelse og påvirkningskraft. På mange måter var Gauslaa i en klasse for seg, med sine mange makt-
posisjoner. Han skilte seg ut i kraft av å være en av ytterst få i Lillesands-
området med høyere utdannelse. Hans erfaringer fra rikspolitikken
hadde stor betydning for hans virke lokalt, som lærer, skolebestyrer og
lokalpolitiker, men ikke minst som redaktør og eier av Lillesands-Posten. Gjennom avisen nådde hans budskap bredt ut til lokalbefolkningen. Det at det stilte sterke lokale kandidater ved de fleste stortingsvalgene,
menn som også hadde en sentral posisjon i lokalpolitikken og ellers i
lokalmiljøet, virket inn på den politiske interessen og fikk velgerne til
valgurnene, enten de var for eller mot den lokale kandidaten. Oppsummering Vi har
samtidig sett at valgoppslutningen varierte sterkt i perioden 1850–1920,
men generelt var økende. En annen linje vi har fulgt, er utviklingen
fra indirekte valg og få stemmeberettigede, til direkte valg og allmenn
stemmerett for både menn og kvinner fra 1913. Kvinnestemmene hadde
avgjørende innflytelse på valgutfallet i 1909. Valgene ble mer politiserte fra 1870-årene. I tiårene på begge sider av
forrige århundreskifte var store og viktige politiske saker på den nasjo-
nale dagsorden, og de politiske partiene stod til dels langt fra hverandre. Sist på 1800-tallet gjaldt det kampen om parlamentarismen, flaggsaken
og konsulatsaken. Det gjaldt også avholdssaken, unionsoppløsningen
og kongevalget samt kvinnestemmeretten. De nasjonale sakene var noe
stemmeberettigede i lokalsamfunnene rundt om i landet skulle ta stilling
til. Gauslaa var både folkeopplyser og meningsbærer, og målbar Venstres
synspunkter i disse og en rekke andre saker. Hva med dimensjonen øst–vest på Agder, forholdet mellom Aust-
og Vest-Agder fylker, og mellom byene langs kysten, særlig Arendal og
Kristiansand? Dette er ikke forhold som har vært mulig å spore i det
foreliggende materialet. Det kan se ut til at disse dimensjonene, og Lille-
sandsområdets marginalisering, først ble en realitet senere på 1900-tallet. Hva som kan forklare det, ligger utenfor tidsrammen til dette kapitlet og 100 hva var det med lillesand? vil kreve nærmere undersøkelser av valgene i hundreårsperioden 1920–
2020. Men noen forklaringer, som ble antydet innledningsvis, kan vi her i
avslutningen utdype noe: Én kan være knyttet til valgordningen. Mellom
1906 og 1918 var det flertallsvalg i enmannskretser. Nåværende Lillesand
kommune (den gang ladestedet Lillesand samt herredene Vestre Moland
og Høvåg) var da ingen utkant, men et relativt folkerikt kystområde i
Sand krets.56 Stortingsvalget i 1921 ble for første gang gjennomført etter
den valgordningen vi siden har hatt: Forholdstallsvalg i flermannskretser. I Aust-Agder fylke ble Lillesandsområdet en utkant. En viss betydning
kan også utviklingen fra valg uten politiske partier, via topartisystem
(med flere stortingsrepresentanter fra hvert parti) til flere partier (og
gjerne bare én Aust-Agder-representant fra de største partiene) ha hatt. Det var åpenbart ikke mulig for en lillesander å bli satt på førsteplassen
på de største partienes lister, og dermed oppnå fast plass på Stortinget. Lillesands marginalisering kan også ha vært et resultat av Kristiansands
vekst og Arendals tilbakegang, og det at vestre deler av Aust-Agder (med
Lillesand) ble trukket mot Kristiansand med åpningen av Varoddbrua i
1956 og stamveien mellom Kristiansand og Lillesand i 1960. 56
Sand krets bestod av de vestlige herredene i Nedenes amt: Herefoss, Fjære, Landvik, Eide,
Birkenes, Vestre Moland og Høvåg samt ladestedet Lillesand. Byene Arendal og Grimstad
(i fellesskap) og Risør valgte egne stortingsrepresentanter Oppsummering Ikke minst i
forbindelse med diskusjonen om sammenslåing av de to fylkene i tiårene
forut for 1. januar 2020, da Aust- og Vest-Agder ble til ett Agder, ble denne
dimensjonen aktualisert. Men da avgjørelsen først var tatt, ble Lillesand –
både på det geografiske og mentale kartet – liggende i sentrum av det nye
Agder. Det har allerede påvirket – og vil sannsynligvis fortsette å påvirke
– valgbarheten til kandidater fra Lillesandsområdet. Lillesand kommunearkiv. Aust-Agder museum og arkiv (AAMA).
Kjell Rosenbergs privatarkiv, Lillesand kommune.
PA-2573. Noan Christian Gauslaa, personarkiv, AAMA.
Lillesands-Posten, årganger 1870–1920. kapittel 4 kapittel 4 Lillesands Tilskuer 1894–95, 1898, 1908. Den vestlandske Tidende 1891. Fylkingen 1938. Kilder Lillesand kommunearkiv. Aust-Agder museum og arkiv (AAMA). Kjell Rosenbergs privatarkiv, Lillesand kommune. PA-2573. Noan Christian Gauslaa, personarkiv, AAMA. Lillesands-Posten, årganger 1870–1920. 101 101 Litteratur Arne Thomassen. (2020, 20. mai). Stortinget.no. https://www.stortinget.no/no/Representanter-og-komiteer/Representantene/
Representant/?perid=ARNT&tab=Biography
Arne Thomassen. (2020, 18. januar). I Wikipedia. https://no.wikipedia.org/wiki/Arne_Thomassen
Bjørnstad K (1949) Stortinget og statsrådet 1915 1945: Bd II De enkelte Storting Bjørnstad, K. (1949). Stortinget og statsrådet 1915–1945: Bd. II. De enkelte Storting. Aschehoug. Bjørnstad, K. (1949). Stortinget og statsrådet 1915–1945: Bd. II. De enkelte Storting. Aschehoug. Centrum. (2018, 16. oktober). I Wikipedia. https://no.wikipedia.org/wiki/Centrum Christian Michelsens regjering. (2018, 16. oktober). I Lokalhistoriewiki. https://lokalhistoriewiki.no/Christian_Michelsens_regjering Gauslaa, N. Chr. [Lillesands Sparebank] (1927). Lillesands Sparebank 1852 – 11. oktober – 1927. Harald Lyche & Co. Høegh-Omdal, A. U. (1977). Stortingsvalget i Nedenes amt 1909 [Hovedoppgave]. Universitetet i Oslo. Jorunn Gleditsch Lossius. (2020, 30. mai). Stortinget.no. https://www.stortinget.no/
no/Representanter-og-komiteer/Representantene/Representant/?perid=JLOt Kristian Sundtoft. (2020, 30. mai). Stortinget.no. https://www.stortinget.no/no/
Representanter-og-komiteer/Representantene/Representant/?perid=KRSt Kristian Sundtoft. (2020, 18. januar). I Wikipedia. https://no.wikipedia.org/wiki/Kristian_Sundtoftt Larsen, E. & Øksendal, L. F. (2013). De glemte kvinnevalgene. Historisk tidsskrift,
92(4), 563–590. https://www.idunn.no/ht/2013/04/de_glemte_kvinnevalgenei Lindstøl, T. (1914a). Stortinget og statsraadet 1814–1914. Biografier (Bd. I, del I). Steen’ske bogtrykkeri. Lindstøl, T. (1914b). Stortinget og statsraadet 1814–1914. Biografier (Bd. I, del II). Steen’ske bogtrykkeri. Lindstøl, T. (1914c). Stortinget og statsraadet 1814–1914. De enkelte storting og
statsraader (Bd. II, del I). Steen’ske bogtrykkeri. Lindstøl, T. (1915). Stortinget og statsraadet 1814–1914. De enkelte storting og
statsraader (Bd. II, del II). Steen’ske bogtrykkeri. Liste over Norges regjeringer. (2018, 16. oktober). I Wikipedia. https://no.wikipedia.org/wiki/Liste_over_Norges_regjeringer Liste over stortingsrepresentanter 1892–1894 (2020, 12. februar). I Wikipedia. https://
no.wikipedia.org/wiki/Liste_over_stortingsrepresentanter_1892%E2%80%931894 Liste over stortingsrepresentanter 1892–1894 (2020, 12. februar). I Wikipedia. https://
no.wikipedia.org/wiki/Liste_over_stortingsrepresentanter_1892%E2%80%931894 102 hva var det med lillesand? Moderate Venstre. (2018, 16. oktober). I Wikipedia. https://no.wikipedia.org/wiki/
Moderate_Venstre Rosenberg, K. (1990). Lillesand historie I. Mennesker, by og boliger. Lillesandsposten. Stangeby, K. (2011). Hansen & Narvesen 100 år. Hansen & Narvesen. Stangeby, K. (2011). Hansen & Narvesen 100 år. Hansen & Narvesen. Statistisk sentralbyrå. Valgmandsvalgene og Storthingsvalgene 1815–1885 [Statistikk]. https://www.ssb.no/a/histstat/nos/nos_iii_219.pdf Stortingsvalget 1906. (2018, 16. oktober). I Wikipedia. Stortingsvalget 1906. (2018, 16. oktober). I Wikipedia. https://no.wikipedia.org/wiki/Stortingsvalget_1906 https://no.wikipedia.org/wiki/Stortingsvalget_1906 Søbye, E. & Dørum, K. (2020, 2. januar). Stemmerettens historie i Norge. I Store
norske leksikon. https://snl.no/Stemmerettens_historie_i_Norge Søbye, E. & Dørum, K. (2020, 2. januar). Stemmerettens historie i Norge. I Store
norske leksikon. https://snl.no/Stemmerettens_historie_i_Norge Sødal, T. (2013). Høvåg. Gårds- og slektshistorie: Bd. 1. Portal forlag. Sødal, T. (2013). Høvåg. Gårds- og slektshistorie: Bd. 1. Portal forlag. Torjus Værland. (2018, 26. oktober). I Wikipedia. https://no.wikipedia.org/wiki/Torjus_V%C3%A6rland Torjus Værland. (2018, 26. oktober). I Wikipedia. https://no.wikipedia.org/wiki/Torjus_V%C3%A6rland Tvedt, K. A. (2017, 10. november). Mandatfordeling på Stortinget 1882–1936. I Store
norske leksikon. https://snl.no/Mandatfordeling_p%C3%A5_Stortinget_1882-1936 Tvedt, K. A. Litteratur (2017, 10. november). Mandatfordeling på Stortinget 1882–1936. I Store
norske leksikon. https://snl.no/Mandatfordeling_p%C3%A5_Stortinget_1882-1936 Tvedt, K. A. (2019, 31. oktober). Stortingsvalg – resultater 1882–2017. I Store
norske leksikon. https://snl.no/Stortingsvalg_-_resultater_1882-2017#-
Stortingsvalg_1906-1915 Tvedt, K. A. (2019, 31. oktober). Stortingsvalg – resultater 1882–2017. I Store
norske leksikon. https://snl.no/Stortingsvalg_-_resultater_1882-2017#-
Stortingsvalg_1906-1915 Udjus, V. (2018, 28. november). Dette er vinneren av ett Agder [Kommentar]. Fædrelandsvennen. https://www.fvn.no/mening/kommentar/i/0E87x0/dette-er-
vinneren-av-ett-agder Udjus, V. (2018, 28. november). Dette er vinneren av ett Agder [Kommentar]. Fædrelandsvennen. https://www.fvn.no/mening/kommentar/i/0E87x0/dette-er-
vinneren-av-ett-agder Worm-Müller, J. S. (1935). Fra klipperen til motorskibet. I F. Scheel & J. S. Worm-
Müller, Den norske sjøfarts historie, s. 235–705. Oslo: Steenske Forlag. Worm-Müller, J. S. (1935). Fra klipperen til motorskibet. I F. Scheel & J. S. Worm-
Müller, Den norske sjøfarts historie, s. 235–705. Oslo: Steenske Forlag. 103 kapittel 5 Sitering av dette kapitlet: Hundstad, D. (2020). Frivillige organisasjoner og regionbygging. Et eksem-
pel fra Agder. I Johnsen, B.E. og Vadum, K. (red.), Grenseløst Agder. Det som skilte og det som bandt
(s. 104–123). Oslo: Cappelen Damm Akademisk. https://doi.org/10.23865/noasp.111
Lisens: CC BY-NC-ND. Frivillige organisasjoner
og regionbygging
Et eksempel fra Agder Dag Hundstad Den 1. januar 2020 ble Aust- og Vest-Agder slått sammen til én fylkes-
kommune. Agder er blitt én administrativ enhet. Samtidig er det ingen
tvil om at Agder/Sørlandet eksisterte som identitetsregion også før denne
sammenslåingen. Det er vanskelig å dokumentere regional identitet, men
ved å bruke fylkesoverskridende organisasjoner som inngang, kan en i
det minste kartlegge i hvilken grad landsdelen har fungert som et rele-
vant og hensiktsmessig territorielt rammeverk for frivillig samhandling. Dette kan i sin tur si noe om regional tilknytning og identifikasjon. I dette kapitlet vil jeg undersøke hvilken rolle de fylkesoverskridende
organisasjonene har spilt for regionbyggingen på Agder før fylkes
sammenslåingen. Dette spørsmålet kan jeg ikke se har vært stilt tidligere,
og det finnes få relevante studier å bygge på. I og med at det ikke er oppret-
tet noen database eller utarbeidet noen oversikt over det historiske orga-
nisasjonskartet i landsdelen, må vi ty til andre analyseverktøyer. Agder
Historielag vil bli brukt som et eksempel på en fylkesoverskridende orga-
nisasjon. Felles historieforståelse er et grunnleggende premiss for å skape
en regional samhørighet, og spørsmålet er da i hvilken grad historielaget
har bidratt i regionbyggingen. Først vil jeg imidlertid introdusere noen
sentrale begreper knyttet til regioner og organisasjoner. 104 frivillige organisasjoner og regionbygging 1
For en drøfting av regionbegrepet, se Hundstad 2013a: 26 ff.
2
Hundstad 2013b: 110
3
Hundstad 2013b: 78 ff
4
Østerud 1994: 24 Regioner og regionbygging Blant norske historikere brukes oftest regionbegrepet om områder som
er større enn et enkelt lokalsamfunn, men som ikke samsvarer med offi-
sielle administrative inndelinger som kommuner og fylker. En region er
likevel et utydelig begrep, som brukes på ulikt vis i ulike fagdisipliner. I geografisk forstand kan dette stå for enhver form for områdeinnde-
ling, og det finnes et utall ulike regioninndelinger. Ofte snakker man om
homogene regioner, der inndelingen er basert på likheter av ulikt slag. Når
det gjelder Agder, er det vanskelig å finne entydige likheter som samler
hele regionen ut fra naturgitte eller kulturelle forhold, og regionen har
heller ikke det en kan kalle naturlige grenser. Det var også først i 2020
at Agder ble en administrativ region hvis vi ser på politikk og offentlig
administrasjon. Agder kan heller ikke sies å være en funksjonell region,
i den forstand at alle de ulike delene av regionen utfyller hverandre i en
eller annen form for økonomisk eller sosialt system.1 Det som gir mer mening er å drøfte Agder opp mot begreper som
identitetsregion og referanseregion. Agder – eller Sørlandet – er en geo-
grafisk referanseenhet i kraft av å være et landsdelsnavn. Iallfall fra ca. 1915 har dette vært en av fem norske hovedlandsdeler, slik vi ser dette
gjenspeilet i offentligheten.2 Mennesker tenker seg geografiske størrelser i
et hierarkisk system, og her kommer landsdelen inn som et mentalt refe-
ransepunkt på et nivå mellom lokalsamfunnet og nasjonen. Er så Agder
en identitetsregion? Her vil svaret avhenge av hvem vi spør. Det er i det
minste en kollektiv identitet knyttet til begrepet Sørlandet, som forfatte-
ren Vilhelm Krag introduserte i 1902. Krag var en regional poetokrat, og
må betraktes som den mest sentrale regionbyggeren på begynnelsen av
1900-tallet.3 Regionbygging kan, i analogi med begrepet nasjonsbygging,
defineres som summen av direkte og indirekte virkemidler i utviklingen
av et opplevd regionalt fellesskap.4 Sørlandsbegrepet banet vei for en sør-
landsk regionalisme som kulminerte i mellomkrigstiden, og som 105 kapittel 5 resulterte i at Sørlandet ble et sterkt varemerke, knyttet til bestemte sym-
boler og verdier.5 Det vi kan kalle sørlandsfortellingen er formidlet blant annet gjennom
kunstnerisk og litterær iscenesettelse og utvikling av sørlandskysten som
turistdestinasjon fra mellomkrigstiden og framover. Regioner og regionbygging Den tyske kultur-
historikeren Hermann Bausinger har påpekt det symbiotiske forholdet
mellom kunstnerisk iscenesettelse og turisme, som til sammen kan skape
sterke narrativer.6 I denne prosessen blir enkelte sider ved regionen som
betraktes som «typiske», framhevet. Andre blir sett på som ikke repre-
sentative og marginaliseres eller ekskluderes. På denne måten skapes og
reproduseres det den finske geografen Anssi Paasi kaller regionens for-
ventningsstrukturer. Disse strukturene er igjen med på å organisere vår
tenkning om de romlige sidene ved tilværelsen.7 For Sørlandets del var det kyststrekningen, det dikteren Gabriel Scott
kalte «det egentlige Sørland», som ble framhevet.8 Hverken mellom- eller
fjellbygdene ble på samme måte skrevet inn i sørlandsfortellingen. Ser
vi på Agder-begrepet, konnoterte dette til de administrative størrelsene
Vest- og Aust-Agder. På den måten virket det mer geografisk inklude-
rende, men også mindre symbolladet. Fylkesoverskridende organisa-
sjoner har likevel både tatt sørlands- og agderbegrepet i bruk, noe som
viser at Sørlandet også har fått funksjon av å være et landsdelsnavn, del-
vis synonymt med Agder. Da Agder Historielag ble stiftet i 1914, var det
imidlertid naturlig å ta i bruk agderbegrepet, som potensielt kunne virke
mer samlende, og som hadde historiske røtter. På denne tiden var det en
vekst i regionale organisasjoner over hele landet. 5
Om den sørlandske regionalismen og regionbyggingen se for øvrig: Hundstad 2013.
6
Bausinger 1998
7
Paasi 1986
8
Scott 1937/2010 9
Berg, 2014; Steen 1948: 583; Østerberg 1997: 60
10
Meld. St. 10 (2018–2019): 24
11
Myhre 2020; Raaum 1988
12
Steen 1948, se også Onarheim & Selle 1994: 6–7
13
Kirkhusmo 1974: 436; Try 1985: 33 ff
14
Anderson 1983 kapittel 5 Generelt er 1900-tallet preget av så vel kvantitativ vekst som nydannel-
ser av organisasjoner. En fikk både nasjonale sentralledd for eksisterende
lokale og regionale lag, samtidig som det ble dannet paraplyorganisasjoner
for større sektorer.15 Det er forsket en del på organisasjonssamfunnets fram-
vekst på 1800-tallet. Til sammenligning har norske historikere vært over-
raskende lite opptatt av den generelle organisasjonshistorien fra 1900-tallet
til i dag. Statsviteren Per Selle har imidlertid levert en rekke bidrag som
er relevante for den moderne organisasjonshistorien.16 I min sammenheng
har Per Selle og Per Arne Hestetuns undersøkelse av fylkes- og kretsnivået
i organisasjoner i Hordaland i 1980-årene vært særlig nyttig.17 Lokale organisasjoner er med på å skape romlig identifikasjon og
tilknytning til lokalsamfunnet.18 Et forhold som ikke er ofret nok opp-
merksomhet, er at organisasjonene har vært med på å knytte ulike deler
av nasjonen sammen. Organisasjonenes hierarkiske struktur gjorde at
de var med på å binde sammen ulike lokalsamfunn til landsdeler eller
regioner og ulike landsdeler til en nasjon. I tillegg arrangerte de utstillin-
ger, stevner og konkurranser som ble regionale møteplasser. De regionale
organisasjonene var tidstypiske innslag på begynnelsen av 1900-tallet, da
interessen for å fremme bestemte regioner og skape flere fasetter i den
nasjonale fortellingen førte til en generelt økt interesse for det regionale.19
Hvordan slo dette ut på Agder? Samlet de frivillige organisasjonene de to
fylkene til et rike? 16
Se bl.a. Folkestad, Christensen, Strømsnes & Selle 2015; Selle & Øymyr 1995; Wollebæk & Selle
2002 15
Forenings- eller organisasjonshistorie i lokalhistoria, Lokalhistoriewiki 15
Forenings- eller organisasjonshistorie i lokalhistoria, Lokalhistoriewiki
16
Se bl.a. Folkestad, Christensen, Strømsnes & Selle 2015; Selle & Øymyr 1995; Wollebæk & Selle
2002
17
Selle & Hestetun 1990
18
Spilling & van der Ros 1985: 25
19
Hundstad 2015a 18
Spilling & van der Ros 1985: 25 Organisasjoner En organisasjon kan defineres som en kollektiv medlemsmasse som er
bygget opp for å fremme ett eller flere formål eller verdier. Organisasjoner
er fastere enn mange andre typer grupper. De er oftest formalisert i en 106 frivillige organisasjoner og regionbygging eller annen forstand. Det vil si at de har regler og autoritetsrelasjoner, de
er basert på arbeidsdeling og har en eller annen form for begrensning når
det gjelder medlemskap.9 Etter denne definisjonen kan både bedrifter og
byråkratiske organer regnes som organisasjoner, men i det følgende vil jeg
se bort fra disse, og konsentrere meg om frivillige organisasjoner. I dag
ligger Norge på topp internasjonalt når det gjelder frivillig deltakelse. I 2018 hadde 63 prosent av befolkningen deltatt i slikt arbeid de siste tolv
månedene. Verdien av frivillig arbeid i Norge tilsvarer nærmere 148 000
årsverk.10 Agder Historielag er et eksempel på en frivillig, allmennyttig
organisasjon, og et vanlig synonym for slike organisasjoner er foreninger. I norgeshistorien dateres organisasjonssamfunnets framvekst fra ca. 1840. Da etablerte det seg politiske organisasjoner, yrkesorganisasjo-
ner, økonomiske organisasjoner, kultur- og opplysningsorganisasjoner
og organisasjoner knyttet til spesifikke ideologiske formål som misjon,
avhold og måtehold eller filantropi. I løpet av 1800-tallet bredte organisa-
sjonene seg til alle deler av landet, og omfattet etter hvert nesten alle sosi-
ale lag og sektorer av samfunnslivet. Antallet nasjonale foreninger vokste
fra 10 i 1850 til 154 i 1900.11 I en mye sitert artikkel fra 1948 framhevet historikeren Sverre Steen
at bestemte grupper kunne bruke organisasjonene instrumentelt for å nå
bestemte mål. Videre så han dem i relasjon til behov som staten eller eldre
sosiale fellesskap ikke maktet eller ønsket å fylle.12 Senere har Steens syn
blitt kalt «instrument- og tomromsteorien», og har blant annet vært dis-
kutert av historikerne Hans Try og Anders Kirkhusmo.13 Disse etterspurte
blant annet lokal empiri som bakgrunn for teoriene. Det vi også kan si er
at organisasjonene peker framover mot det sosiologen Benedict Ander-
son kaller et forestilt fellesskap, idet de var basert på horisontale bånd og
en viss sosial åpenhet.14 Dette gjorde at de kunne utvikle seg til brede og
landsdekkende folkebevegelser, som avholdsbevegelsen, lekmannsbeve-
gelsen og arbeiderbevegelsen. 107 kapittel 5 Bruken av «Agder» og
«Sørlandet» i organisasjonsnavn Historikeren Jens Arup Seip
betegnet denne bevegelsen som en «venstrehær».21 Mer nøytralt ville
det ha vært å bruke de offisielle navnene på amtene (henholdsvis Lister
og Mandals amt og Nedenes amt). En mer praktisk side ved saken er at
Agder (eventuelt Agdesiden) var det eneste naturlige fellesnavnet det var
mulig å gripe til når en skulle omtale begge de to amtene. I tilfellet Agders
Lodsforening (stiftet 1893), er nok bruken av Agder-begrepet grunnet i et
ønske om et hensiktsmessig fellesnavn.22 Slettan har vist at navnet fra midten av 1800-tallet i økende grad ble brukt
i ulike sammenhenger, deriblant som organisasjonsnavn.20 Dette kan en
se i sammenheng med en allmenn nasjonal og historiserende bølge, der en
grep tilbake til arkaiske navn. I tillegg kan bruken også fortelle om regio
nale ambisjoner og identitet. Ser vi f.eks. på Vest- og Aust-Agder Ung-
domslag eller Vest- og Aust-Agder Lærerlag, kan det være rimelig å tolke
bruken av Agder-navnet som et bevisst uttrykk for språklig nasjonalisme. Det samme gjelder skytterlagsbevegelsen, der navnene var henholdsvis
Aust- og Vest-Agder Folkevæbningssamlag. Historikeren Jens Arup Seip
betegnet denne bevegelsen som en «venstrehær».21 Mer nøytralt ville
det ha vært å bruke de offisielle navnene på amtene (henholdsvis Lister
og Mandals amt og Nedenes amt). En mer praktisk side ved saken er at
Agder (eventuelt Agdesiden) var det eneste naturlige fellesnavnet det var
mulig å gripe til når en skulle omtale begge de to amtene. I tilfellet Agders
Lodsforening (stiftet 1893), er nok bruken av Agder-begrepet grunnet i et
ønske om et hensiktsmessig fellesnavn.22 Som nevnt ble sørlandsbegrepet lansert i 1902. Etter relativt få år var
navnet naturalisert, og ble brukt aktivt i ulike sammenhenger. I denne
sammenhengen var avisene viktige, først avisen Sørlandet, som ble
grunnlagt allerede i 1906, deretter Fædrelandsvennen, som ved å knytte
seg til sørlandsbegrepet ville markere sine territorielle ambisjoner og bli
en landsdelsavis. Senere gikk sørlandsbegrepet inn i hele den regionale
og lokale pressen. Området begrepet omfatter er noe utflytende, men
hovedsakelig brukes det om de to sørligste amtene (Lister og Mandals
og Nedenes), som et parallelt landsdelsnavn til Agder. Av og til er likevel
også deler av Telemark og Rogaland med.23 Den offisielle «konfirmasjonen» av sørlandsbegrepet er gjerne satt til
1913. Da vedtok Stortinget, etter tre år med diskusjoner, og motstand fra
Rogaland, at den planlagte jernbanestrekningen mellom hovedstaden og
Stavanger skulle skifte navn fra Vestlandsbanen til Sørlandsbanen. 20
Slettan 1998: 56–57
21
Seip 1981: 97, 194
22
Vestmar 10.08.1896
23
Hundstad 2013b: 95 ff Bruken av «Agder» og
«Sørlandet» i organisasjonsnavn Først i 1919 ble fylkesnavnene Aust- og Vest-Agder introdusert. Før den
tid var navnene Nedenes amt og Lister og Mandals amt. Selv om Agder-
navnet ikke var offisielt, ble det likevel benyttet. Historikeren Bjørn 108 frivillige organisasjoner og regionbygging Slettan har vist at navnet fra midten av 1800-tallet i økende grad ble brukt
i ulike sammenhenger, deriblant som organisasjonsnavn.20 Dette kan en
se i sammenheng med en allmenn nasjonal og historiserende bølge, der en
grep tilbake til arkaiske navn. I tillegg kan bruken også fortelle om regio
nale ambisjoner og identitet. Ser vi f.eks. på Vest- og Aust-Agder Ung-
domslag eller Vest- og Aust-Agder Lærerlag, kan det være rimelig å tolke
bruken av Agder-navnet som et bevisst uttrykk for språklig nasjonalisme. Det samme gjelder skytterlagsbevegelsen, der navnene var henholdsvis
Aust- og Vest-Agder Folkevæbningssamlag. Historikeren Jens Arup Seip
betegnet denne bevegelsen som en «venstrehær».21 Mer nøytralt ville
det ha vært å bruke de offisielle navnene på amtene (henholdsvis Lister
og Mandals amt og Nedenes amt). En mer praktisk side ved saken er at
Agder (eventuelt Agdesiden) var det eneste naturlige fellesnavnet det var
mulig å gripe til når en skulle omtale begge de to amtene. I tilfellet Agders
Lodsforening (stiftet 1893), er nok bruken av Agder-begrepet grunnet i et
ønske om et hensiktsmessig fellesnavn.22 Slettan har vist at navnet fra midten av 1800-tallet i økende grad ble brukt
i ulike sammenhenger, deriblant som organisasjonsnavn.20 Dette kan en
se i sammenheng med en allmenn nasjonal og historiserende bølge, der en
grep tilbake til arkaiske navn. I tillegg kan bruken også fortelle om regio
nale ambisjoner og identitet. Ser vi f.eks. på Vest- og Aust-Agder Ung-
domslag eller Vest- og Aust-Agder Lærerlag, kan det være rimelig å tolke
bruken av Agder-navnet som et bevisst uttrykk for språklig nasjonalisme. Slettan har vist at navnet fra midten av 1800-tallet i økende grad ble brukt
i ulike sammenhenger, deriblant som organisasjonsnavn.20 Dette kan en
se i sammenheng med en allmenn nasjonal og historiserende bølge, der en
grep tilbake til arkaiske navn. I tillegg kan bruken også fortelle om regio
nale ambisjoner og identitet. Ser vi f.eks. på Vest- og Aust-Agder Ung-
domslag eller Vest- og Aust-Agder Lærerlag, kan det være rimelig å tolke
bruken av Agder-navnet som et bevisst uttrykk for språklig nasjonalisme. Det samme gjelder skytterlagsbevegelsen, der navnene var henholdsvis
Aust- og Vest-Agder Folkevæbningssamlag. Bruken av «Agder» og
«Sørlandet» i organisasjonsnavn Vi ser
også på denne tiden at det i økende grad ble grepet til sørlandsnavnet 109 kapittel 5 i organisasjonssammenheng. Dette viser at navnet var etablert som et
anvendelig fellesnavn, men kanskje også at en identifiserte seg med den
sørlandske regionalismen. En av organisasjonene som var først ute med
sørlandsnavnet var Sørlandske Fodboldkreds, som ble stiftet i 1911. Tidlig
ute var også Sørlandets Seilforening, som ble stiftet i 1912, men denne
organisasjonen gikk senere under navnet Agder Seilkrets. Flere organi-
sasjoner fulgte på, f.eks. kom Sørlandets Sangerforbund i 1914.24 Vi kan
altså observere at en del organisasjoner eller organisasjonsledd gjennom
sine navn viser at de hadde ambisjoner om å dekke begge de to sørligste
fylkene. Vi skal nå se nærmere på én av disse organisasjonene, Agder
Historielag, der vi finner at landsdelsambisjonene i navnet ikke alltid var
til stede i gavnet. f
25
Hvis ikke annet er angitt, er delen om Agder Historielag basert på Hundstad 2015.
26
Alsvik 1998: 8–9 24
Hundstad 2013b: 103 ff Agder Historielag og
den regionale historiekulturen25 På begynnelsen av 1900-tallet ble det etablert mange historielag rundt
om i landet. Historikeren Ola Alsvik ser framveksten av den moderne
lokalhistorien i relasjon til tre faktorer: Moderniseringen av det norske
bygdesamfunnet med et påfølgende konserverende behov for å ta vare
på den lokale fortida som var i ferd med å forsvinne, nasjonsbyggings-
prosjektet og utviklingen av historiedisiplinen etter 1905, da historikerne
kunne konsentrere seg om andre problemstillinger enn de politiske og
nasjonale.26 I 1913 satte Den norske historiske forening ned en egen komité for
lokalhistorie. Utgangspunktet for denne komitéen var ikke minst et
kontrollbehov. Planleggingen av grunnlovsjubileet i 1914 resulterte i
en strøm av lokalhistoriske publikasjoner, og en del av disse var på et
nivå faghistorikerne ikke anerkjente. Dette illustrerer lokalhistoriens
plass i et spenningsfelt mellom folkelig grasrotvitenskap og de auto-
riserte kulturarvsdiskursene, særlig representert ved profesjonelle 110 110 frivillige organisasjoner og regionbygging kulturverninstitusjoner og universitetshistorikere.27 En av komiteens
anbefalinger når det gjaldt lokalhistorien var at en burde gå sammen i
regionale lag. Den viste blant annet til at det forelå planer om et regionalt
historielag i Agder. Da Agder Historielag ble stiftet i 1914, møttes to nye og friske feno-
mener i tiden: Den sørlandske regionalismen, sparket i gang av Vilhelm
Krag få år tidligere, og en sterk interesse for lokalhistorie. På Agder mani-
festerte dette seg blant annet ved at amtmann Daniel Koren i Lister og
Mandals amt i 1914 utgav boken Omkring Lindesnæs, som ble delt ut som
et kulturelt visittkort til alle landets stortingsrepresentanter. Koren fram-
hevet, i motsetning til tidligere forfattere, at Agder hadde mye av histo-
risk verdi å by på. Han uttalte også at den historiske litteraturen skulle
«samarbeide amtets forskjellige distrikter», slik at en kunne stå samlet og
få større innflytelse. Etableringen av Agder Historielag bar preg av kristiansandsk kultur
elite, men det gikk likevel ikke lange tiden før det viste seg at det var
andre miljøer som måtte bære laget. På bygdene var lærerne de kul-
turelle matadorer, og gikk med liv og lyst inn for lokalhistorien. Den
lokalhistoriske diskursen ble på denne tiden trukket dypt inn i norsk-
domsrørsla og agrarnasjonalismen, og Tordenskjolds soldater gikk igjen,
enten det var snakk om ungdomslag, mållag, avholdslag – eller historie
lag. Lokalhistorien skulle «binde den unge ætti til fedrejordi», slik
historielagsmannen Jon Løyland uttrykte det. Fikk man så egentlig «samarbeidet landsdelen» etter Korens ønske? 27
Smith 2006: 4; se også Eriksen 1999: 14 Agder Historielag og
den regionale historiekulturen25 Laget ga ut sine årsskrifter, først kalt Bidrag til Agders historie, men lå
ellers stort sett i dødvanne fram til slutten av 1920-årene. Blant lokal
historikerne i landsdelen var det arbeidet med bygdebøker og slekts
historie som fikk størst oppslutning. Historielagets medlemmer var
også ujevnt fordelt i landsdelen. Utenom Kristiansand var det få med fra
byene, og Arendal og distriktene østover var så å si fraværende. I 1920
startet to lokalhistorikere fra den østligste delen av Aust-Agder, Tallak
Lindstøl fra Søndeled og Jens Vevstad fra Gjerstad, et eget historielag for
fylket. Begge hadde lang fartstid som medlemmer av Agder Historielag, 111 kapittel 5 men de følte nok at et lag med tyngdepunkt i Kristiansand ble noe fjernt
for dem. Agder Historielag gjorde flere ganger framstøt om sammen
slåing, men etter bare fem–seks år sovnet Aust-Agder Historielag inn. Et
håndgripelig resultat av arbeidet var lagets skriftserie, der det utkom i alt
åtte bind. Tittelen var Bidrag til Aust-Agders historie, et svar på Bidrag til
Agders historie. Etter andre verdenskrig ønsket Agder Historielag å ekspandere mot øst. I 1949 fikk Aust-Agder fylkesting omvisning på Statsarkivet i Kristian
sand, og styret i Agder Historielag møtte da opp og ga en orientering. Formannen, Jon Løyland, ga uttrykk for at det mislykkede forsøket på
å starte eget historielag for Aust-Agder viste at man burde samles i ett
felles lag for landsdelen. Samme år ble årsmøtet i Agder Historielag lagt
til Arendal gamle rådhus. Frammøtet var stort, og alle som hadde ordet
mente man burde samles. Leder av Arendals Museum, Albert Ugland, ble
valgt inn som den første arendalitt i styret. I etterkrigsårene fikk Aust-
Agder også gjennomslag for å få en egen arkivinstitusjon, noe som hadde
skapt mye splid etter opprettelsen av Statsarkivet i Kristiansand i 1935. Da Aust-Agder-Arkivet ble opprettet i 1958, ble det særskilt spesifisert
at institusjonen skulle fremme lokalhistorisk forskning enten ved egne
publikasjoner, eller publikasjoner i samarbeid med Agder Historielag. Likevel var spenningen mellom øst og vest ikke borte. Da Landslaget
for lokalhistories årsmøte i 1964 skulle legges til Kristiansand med Agder
Historielag som arrangør, ønsket ikke Aust-Agder-Museet og Aust-Agder-
Arkivet å bidra. Lederen i Landslaget, den lokalhistoriske høvdingen Lars
Reinton, ble skuffet. Han hadde selv bodd i Arendal, og han hadde betrak-
tet det som en selvfølge at Agder Historielag representerte begge fylkene. Agder Historielag og
den regionale historiekulturen25 I Arendal uttalte man imidlertid at man så på årsmøtet som et kristian
sandsarrangement, og en planlagt ekskursjon til Arendal måtte utgå. Fra 1970-årene utvidet Agder Historielag sitt virkefelt, og framstod
etter hvert som en paraplyorganisasjon for historielagene i hele lands-
delen. Laget tok initiativ til omfattende faglige prosjekter, deriblant utgi-
velse av kildeskrifter og to bibliografier, bokverket Agders historie og
dokumentasjon av kystkulturen. Medlemsbladet Egde ble en ny kommu-
nikasjonsplattform, som skulle «gjøre medlemmene til en egde». Dette
forteller om et instrumentelt syn på forholdet mellom historiebevissthet 112 frivillige organisasjoner og regionbygging og regional identitet. Fortsatt dominerte vest-egdene blant medlemmene,
men aust-egdene var langt bedre representert enn tidligere. Historikeren
Hans Try, en av lagets mest markante støttespillere, uttalte i 1982 at Agder
Historielag var ett av de få tiltakene som motvirket splittelsen i lands
delen. De geografiske spenningene i laget var imidlertid til stede i mange
år, der en kunne se en tydelig konfliktakse mellom øst og vest. Vi forlater lagshistorikken her, men konstaterer at historielaget gjen-
nom en rekke tiltak, som publikasjoner, seminarer og andre aktiviteter,
lyktes å etablere «Agder-historie» som et eget felt. Én ting var å snakke
om landsdelens felles historie i høystemte ordelag, slik Krag og andre
regionalister gjorde på begynnelsen av 1900-tallet. Noe helt annet var
å operasjonalisere en slik tankegang i konkrete prosjekter. Tidligere
har vi også sett andre eksempler på organisasjoner som omfattet begge
Agder-fylkene. Hva slags rolle spilte slike organisasjoner i forhold til lag
og foreninger som dekket bare Aust- eller Vest-Agder fylke? 28
Om mellomnivået i organisasjonene, se Selle & Hestetun 1990. Fylkesoverskridende organisasjoner Med oppbyggingen av de moderne organisasjonene fikk vi en økende
standardisering av organisasjonsmodeller. Det ble etter hvert vanlig å
få en nasjonal organisasjon med et regionalt mellomledd, som på ulike
måter stod for service og kommunikasjon til lokallagene. Agder Historie-
lag, som var medlem av Landslaget for lokalhistorie og betjente de lokale
historielagene, er et eksempel på dette. I de senere tiårene har det vært
vanligst at slike mellomledd har omfattet ett enkelt fylke, men tidligere
var en organisering i mindre kretser i et fylke også utbredt. Videre viser
eksemplene fra Agder at mellomleddet også kunne omfatte flere fylker.28 Det som slår oss når vi ser på organisasjonshistorien på Agder, er for
det første at en hele tiden har hatt en blanding av organisasjoner som
omfattet ett av fylkene og hele Agder. Dette gjelder alle typer frivillige
organisasjoner, inkludert yrkesorganisasjoner. For det andre ser vi mange
eksempler på manglende kontinuitet når det gjelder den regionale organi-
seringen. I ulike perioder av organisasjonshistorien kunne mellomleddet 113 kapittel 5 både være oppdelt i kretser for Aust- og Vest-Agder eller favne hele lands-
delen, uten at vi kan se noen klar linje i denne utviklingen. Et eksempel er den allerede nevnte Sørlandske Fodboldkreds av 1911. Allerede i 1919 ble kretsen delt mellom de to fylkene. Da spørsmålet om
samling ble nevnt i 1929, ble det sett på som for komplisert og kostbart
å reise fra den ene delen av Agder til den andre for å spille fotballkamp. I 1971 fikk en igjen en fylkesoverskridende organisasjon – Agder Fotball-
krets.29 Kommunikasjonene hadde selvsagt forbedret seg i denne peri
oden, men andre organisasjoner gikk i motsatt retning. Nevnte Sørlandets
Seilforening ble i 1977 utgangspunktet for Agder Seilkrets, etter et kort
mellomspill med egen fylkeskrets for Aust-Agder. I 1988 ble kretsen igjen
splittet i to fylkeskretser.30 Agdesiden krets av Norges Kristelige Ung-
domsforbund ble opprettet i 1894, men allerede i 1906 ble kretsen delt i to,
før den igjen ble samlet i 1959.31 På tross av et inntrykk av diskontinuitet,
finnes det også eksempler på det motsatte. Korpsbevegelsen i landsdelen
ble i 1931 samlet i Agder krets av Norges Landsforbund av Gutte- og Ung-
domskorps. 29
Agderposten 09.03.1929, 18.03.1929; Fædrelandsvennen 11.01.1971, 16.08.1988
30
Fædrelandsvennen 30.03.1977, 29.08.1989
31
Fædrelandsvennen 21.04.1959; Seland 2006: 268
32
Ingskog 1990: 343
33
www.nb.no Fylkesoverskridende organisasjoner Denne modellen ble stående, og etter hvert ble dette faktisk
den eneste kretsorganisasjonen innen korpsbevegelsen som ikke bygget
på ett enkelt fylke.32 Ved å gå inn i enkelte organisasjoners historie kan vi
på denne måten identifisere ulike måter å organisere seg på. For å si noe
mer generelt om utviklingen, kan avisundersøkelser være en vei å gå. 35
«Sørlandet krets» eller «Sørlandets krets» er vesentlig mindre benyttet enn «Agder krets», men
får en viss oppblomstring i 1980- og 1990-årene. Avisundersøkelser I og med at det ikke finnes systematiske og samlende undersøkelser av det
frivillige organisasjonslivet på Agder, kan kvantitative avisundersøkelser gi
en indikator. Nasjonalbibliotekets digitaliserte korpus av norske aviser kan
brukes til en rekke ulike søk som kan kartlegge omtalen av ulike fenomener.33
Omtalen kan da gi en indikasjon på omfanget av fenomenet. Korpuset inne-
holdt på søketidspunktet (februar 2020) 2,6 millioner skannede avisutgaver. 114 frivillige organisasjoner og regionbygging 34
Selle & Hestetun 1990: 28 34
Selle & Hestetun 1990: 28 frivillige organisasjoner og regionbygging I korpuset har jeg konsentrert meg om å søke på begrepet krets/
krins koblet til et geografisk navn. Slett ikke alle organisasjoner bru-
ker krets-begrepet, men der begrepet forekommer i kombinasjon med
områdebetegnelser, må dette antas å vise til mellomleddet av en orga-
nisasjon. Organisasjoner som ikke bruker krets-begrepet, eller som er
særegne for fylket/regionen eller det enkelte lokalsamfunn, blir derimot
ekskludert.34 Slik vi har sett eksempler på, må vi også ta forbehold om at
den geografiske betegnelsen ikke nødvendigvis er fullt ut dekkende for
virksomheten. Navnet «Agder krets», som tilsynelatende omfatter hele
landsdelen, kan vise seg å være bare ett av flere ulike kretsnavn i de to
fylkene, og lag som grenser til andre fylker kan være med i nabofylkets
krets. En må også ta med i beregningen at jo lengre søkestrengen er, jo
større fare blir det for feil i den optiske tegngjenkjenningen (OCR). Med disse forbeholdene på plass kan vi gå i gang med å søke. Et søk på
«Agder krets» får i alt 12 268 treff i aviskorpuset. Dette treffet inkluderer
imidlertid også treff på «Vest-Agder krets» og «Aust-Agder krets». Søking
spesifikt på de to sistnevnte begrepene får henholdsvis 3188 og 3345 treff. Trekker en fra disse tallene, står en igjen med ca. 5700 treff på Agder
krets, og disse må det antas hovedsakelig refererer til fylkesoverskridende
organisasjoner. Summeres tallene for treffene på «Vest-Agder krets» og
«Aust-Agder krets», ser vi at disse står for 53 prosent av treffene. «Agder
krets» får da 47 prosent, noe som antyder en noenlunde jevn fordeling
mellom omtalen av fylkesvise og fylkesoverskridende organisasjonsledd. Søk på «Sørlandet krets» får 1046 treff. Summeres dette med tallene for
«Agder krets», kommer vi opp i 51 prosent treff på fylkesoverskridende
organisasjoner. Disse tallene synes å bekrefte at en helt fra slutten av
1800-tallet og fram til i dag har hatt en blanding av fylkesoverskridende
og fylkesvise organisasjonsledd på Agder. i Ser en på frekvensen av «Agder krets» kronologisk, finner en mode-
rat bruk fram til 1920-årene. Fra da av blir begrepet hyppig omtalt i avi-
sene fram til 2000-tallet, da frekvensen går kraftig ned.35 Årsaken til
nedgangen de senere år kan være at «krets» blir generelt mindre benyttet 115 kapittel 5 i organisasjonsnavn eller at organisasjoner med krets-inndeling har fått
mindre oppslutning, men kan også ha sammenheng med at avisene
generelt inneholder færre omtaler av arrangementer og andre tiltak fra
organisasjonslivet. frivillige organisasjoner og regionbygging Hvor særpreget er så dette innslaget av fylkesoverskri-
dende organisasjoner i norsk sammenheng? 36
Hundstad 2012
37
Selle & Hestetun 1990: 75 41
Når det gjelder utregningen av dette tallet, er det en betydelig forskjell mellom Oslo krets (32 842
treff) og Akershus krets (5635 treff). Sammenligner vi tallene for Oslo og Akershus krets (2631)
med Akershus krets, ser vi at 47 prosent av kretsorganisasjoner som omtales i Akershus også
omfatter Oslo. Tilsvarende vil bare 8 prosent av kretsorganisasjonene som omtales i Oslo også
omfatte Akershus. Oslo og Bærum krets får for øvrig 247 treff, mens det er få andre treff på kret-
ser som omfatter Oslo men bare deler av Akershus, som Follo, (Nedre) Romerike og Lørenskog.
42
Inkludert treff på Trøndelag og Nordmøre. 40
51 prosent medregnet Sørlandet krets. Sterkest landsdelsidentitet i Agder og Trøndelag En analogi til de to Agder-fylkene finner vi i Trøndelag. Også her har en
et felles historisk landsdelsnavn for to fylker som uttrykker et regionalt
fellesskap. I større grad enn på Agder har man et ubestridt landsdels
senter i form av Trondheim, noe som nok har gjort regionbyggingen
mindre omstridt og enklere å operasjonalisere enn på Agder, der en fin-
ner to konkurrerende sentra i form av byene Kristiansand og Arendal. De
to trøndelagsfylkene ble til og med sammenslått to år før regionreformen
i 2020. I 2005 ble trebindsverket Trøndelags historie utgitt, som Norges
første fullstendige kronologiske landsdelshistorie. Dette forteller også om
ambisjoner om en felles historiekultur.36 Søkene i avismaterialet synes å bekrefte likhetene mellom Agder og
Trøndelag. Søker en på «Trøndelag krets» i norske aviser, får en totalt 16 500
treff. Trekker en så fra «Sør-Trøndelag krets» (2761 treff) og «Nord-Trønde-
lag krets» (3277 treff), står en igjen med anslagsvis 10 000 treff, som en må
anta refererer til fylkesoverskridende organisasjoner. Dette utgjør hele 63
prosent av totalt antall treff, mot 37 prosent treff som refererer til fylkesvis
organisering. Hvordan stiller dette seg i resten av landet? Er denne typen fylkes
overskridende organisering med nabofylker et allment fenomen? I Selle
og Hestetuns undersøkelse av Hordaland ser vi at bare 14 av 91 organisa-
sjoner (15 prosent) hadde slik organisering.37 Hva kan avisomtalene fortelle
om andre fylker? Her kan vi først ta en stikkprøve ved å gå til de to fylkene
som fra 2020 utgjør Innlandet fylke, nemlig Hedmark og Oppland fylke. Her får en bare 1324 treff på «Hedmark og Oppland krets» (medregnet
alternativet «Oppland og Hedmark»), og ca. 200 på «Innlandet krets». 116 116 frivillige organisasjoner og regionbygging Til sammenligning får man 10 384 treff på «Oppland krets», og 5728 treff
på «Hedmark krets». Den fylkesoverskridende kretsen får i denne lands-
delen bare 7,5 prosent av treffene. Søkeresultatet synes å vise at Agder og
Trøndelag peker seg ut med et stort antall fylkesoverskridende organisa-
sjoner sammenlignet med Innlandet. Ved å søke på andre mulige fylkes-
overskridende konstellasjoner på norgeskartet, bekreftes dette særpreget. Til sammenligning får man 10 384 treff på «Oppland krets», og 5728 treff
på «Hedmark krets». Den fylkesoverskridende kretsen får i denne lands-
delen bare 7,5 prosent av treffene. Søkeresultatet synes å vise at Agder og
Trøndelag peker seg ut med et stort antall fylkesoverskridende organisa-
sjoner sammenlignet med Innlandet. 38
Medregnet treff på det nynorske begrepet «krins». f f
39
Det er svært få treff (under 0,1 prosent) på følgende fylkesoverskridende kretser: Hedmark +
(Sør-)Trøndelag, Oppland + (Sør-)Trøndelag, Telemark + (Aust-)Agder, Rogaland + Hordaland,
Nordland + (Nord-)Trøndelag, Akershus + Buskerud, Akershus + Hedmark, Møre og Romsdal
+ Sogn og Fjordane. Som nevnt øker sannsynligheten for OCR-feil jo lenger søkestrengen er, jf.
Møre og Romsdal + Sogn og Fjordane. Et Google-søk viser imidlertid at dette kretsnavnet så å
si ikke får treff. En kan heller ikke utelukke alternative kretsnavn når fylkesnavnene blir såpass
omstendelige, men i disse to fylkene synes heller kretsorganiseringen å ha foregått innenfor
mindre enheter (gamle fogderier) i de enkelte fylkene. Sterkest landsdelsidentitet i Agder og Trøndelag Ved å søke på andre mulige fylkes-
overskridende konstellasjoner på norgeskartet, bekreftes dette særpreget. Tabell 1. Avisomtale av fylkesoverskridende kretser i forhold til fylkesvise kretser
Søkestreng – navn på fylkesoverskridende
krets38
Andel av omtaler i forhold til fylkeskretser.39
Prosent
Trøndelag krets
64
Agder krets40
47
Hedmark og Oppland krets
8
Vestfold og Telemark krets
7
Oslo og Akershus krets41
7
Troms og Finnmark krets
5
Vestfold og Buskerud krets
3
Akershus og Østfold krets
3
Sør-Trøndelag og Møre og Romsdal krets42
2
Hordaland og Sogn og Fjordane krets43
2
Rogaland og (Vest-)Agder krets44
1
Nordland og Troms krets
0,4
Buskerud og Oppland krets
0,1 38
Medregnet treff på det nynorske begrepet «krins». f 4
5 p
g
41
Når det gjelder utregningen av dette tallet, er det en betydelig forskjell mellom Oslo krets (32 842
treff) og Akershus krets (5635 treff). Sammenligner vi tallene for Oslo og Akershus krets (2631)
med Akershus krets, ser vi at 47 prosent av kretsorganisasjoner som omtales i Akershus også
omfatter Oslo. Tilsvarende vil bare 8 prosent av kretsorganisasjonene som omtales i Oslo også
omfatte Akershus. Oslo og Bærum krets får for øvrig 247 treff, mens det er få andre treff på kret-
ser som omfatter Oslo men bare deler av Akershus, som Follo, (Nedre) Romerike og Lørenskog. 42
Inkludert treff på Trøndelag og Nordmøre. 44
Inkludert treff på Rogaland og hele Agder. 117 kapittel 5 Agder og Trøndelag synes å peke seg klart ut i landssammenheng når
det gjelder fylkesoverskridende organisasjoner. Undersøkelsen viser
også at Agder-fylkene i stor grad har orientert seg mot hverandre, og
ikke mot nabofylkene i øst og vest – Telemark og Rogaland. «Rogaland
og Agder krets» får bare 66 treff, mens «Rogaland og Vest-Agder» får
29.45 Til sammenligning får «Rogaland krets» 9233. Det virker heller ikke
som Rogaland i denne sammenhengen har orientert seg nevneverdig mot
Hordaland, i og med at «Rogaland og Hordaland krets» bare får 13 treff. Fylket synes altså å ha spilt en svært dominerende rolle for organisa-
sjonene. Ser vi på Telemark, får «Aust-Agder/Agder og Telemark krets»
78 treff, mens «Telemark krets» får 7725. Her får vi noe større utslag over
fylkesgrensa nordover, da «Telemark og Vestfold krets» får 1147 treff. 45
Derimot får Agder og Stavanger krets 349 treff, som hovedsakelig synes å referere til Muham-
medanermisjonen (nåværende Kristen Muslimmisjon). j
j
46
Oslo og Akershus er her et unntak – se omtale i note 41. 47
Selle & Hestetun 1990: 79, 88–91 45
Derimot får Agder og Stavanger krets 349 treff, som hovedsakelig synes å referere til Muham-
medanermisjonen (nåværende Kristen Muslimmisjon).
46
Oslo og Akershus er her et unntak – se omtale i note 41.
47
Selle & Hestetun 1990: 79, 88–91 47
Selle & Hestetun 1990: 79, 88–91 48
Tallene omfatter her perioden fra 1970 til 2018, da de to fylkene i Trøndelag ble sammenslått.
49
Selle & Hestetun 1990: 76–77
50
Paasi 1986: 125–126 Sterkest landsdelsidentitet i Agder og Trøndelag Tabellen ovenfor viser likevel at det ikke er andre fylker som er i nær
heten av den samme treffprosenten for fylkesoverskridende organisasjo-
ner som Trøndelag og Agder.46 Organisasjonsmønsteret i disse to landsdelene passer ikke inn i en
generelt økende strømlinjeforming av organisasjoner i nasjonal sam-
menheng, der fylkesnivået i de fleste sammenhenger sees som det «natur-
lige» mellomnivået. Denne naturliggjøringen kan selvfølgelig ha å gjøre
med at det er fylket som den primære regionale identiteten knyttes til. En annen forklaring er at de frivillige organisasjonenes rolle i større grad
ble anerkjent som et offentlig ansvarsområde da «den nye kulturpolitik-
ken» ble introdusert i 1970-årene. Dette har ført til at organisasjonene i
sterkere grad har knyttet seg opp mot offentlige institusjoner, samtidig
som fylkeskommunens nye rolle fra midten av 1970-årene virket i samme
retning. Organisasjoner som representerte mer enn ett fylke risikerte å
havne mellom to stoler når de gjorde seg avhengige av bevilgninger fra
fylkeskommunen. I Selle og Hestetuns undersøkelse fra Hordaland, ble
det således ikke registrert noen organisasjoner etablert etter 1960 som
ikke hadde fylket som ramme.47 118 frivillige organisasjoner og regionbygging 49
Selle & Hestetun 1990: 76–77 frivillige organisasjoner og regionbygging Ser vi på Agder finner vi derimot at avisomtalene ikke bare tyder på
at den fylkesoverskridende organiseringen har vært opprettholdt, men
til og med har økt etter 1970. I perioden 1920–1969 utgjorde andelen av
omtalene av «Agder krets» 42 prosent i forhold til «Vest-Agder krets» og
«Aust-Agder krets», mens i perioden 1970–2019 utgjorde den 53 prosent. I Trøndelag finner vi riktignok en svak nedgang i samme periode (fra 66
prosent til 60 prosent), men likevel har det her hele tiden vært flest omta-
ler av «Trøndelag krets».48 Den avvikende organiseringen i Trøndelag og Agder kan bunne i ulike
strukturelle forhold, som kommunikasjonsmønstre/topografi og boset-
ningsmønster. Vi kan også relatere det til historiske og kulturelle forhold. Det er påpekt at hvis en organisasjonsmodell først har «satt seg», dreier
det seg ofte om seige strukturer som kan være vanskelige å endre.49 Dis-
kontinuiteten vi ser en del eksempler på i organisasjonene på Agder synes
likevel å tale mot dette. Dette indikerer snarere at organiseringen ofte
har vært gjenstand for debatt, og at landsdelen i slike sammenhenger har
blitt oppfattet som et like relevant nivå som det enkelte fylket. Her kan
vi igjen vise til et begrep som regional identitet (eller identifikasjon) som
forklaringsfaktor. Både i Agder og Trøndelag har følelsen av historisk enhet vært uttrykt
og forsterket gjennom det samlende landsdelsnavnet. Navnet kan sees
som et grunnleggende regionalt symbol.50 Et felles navn betyr også at
man i denne sammenhengen ikke har hatt en barriere som kan ha vært
med på å hindre etableringen av fylkesoverskridende organisasjoner i
andre landsdeler. Historien har mange eksempler på at navnedebatter
kan være intense, og derfor kan ta mye unødig energi fra en organisasjon
eller institusjon. Dette ser vi illustrert ved den nye regionreformen, der
navnespørsmålet har fått mye plass i debatten, men ikke i Agder eller
Trøndelag. Bruken av landsdelsnavnet Agder, som opptrer allerede før
fylkene fikk sitt offisielle navn, indikerer at det også har vært en identitet
knyttet til dette navnet, og dermed til selve landsdelen. 119 kapittel 5 Konklusjoner I dette kapitlet har målet vært å demonstrere en sammenheng mellom
frivillige organisasjoner og regionbygging. Dette er for det første demon-
strert kvalitativt, med Agder Historielag som eksempel. Historie kan
bygge både nasjoner og regioner, og i regionpatriotismens ånd oppstod
det en mer eller mindre berettiget forestilling om at Agder hadde en felles
historie, og at denne historien var et eget felt man kunne studere. Vi har
likevel sett at det tok mange år før laget fikk fotfeste over hele landsdelen,
til tross for ambisjonene som ble uttrykt i navnet på organisasjonen. Dernest har jeg gjort en kvantitativ undersøkelse som viser at fylkes
overskridende organisasjoner har spilt en langt sterkere rolle på Agder
enn i andre landsdeler, med unntak av Trøndelag. De mange fylkesover-
skridende organisasjonene illustrerer at landsdelen har vært betraktet
som en like «naturlig» operasjonell enhet som det enkelte fylket. Dette
kan både ha med strukturelle og identitetsmessige forhold å gjøre. Sam-
tidig ser vi, som vist i Agder Historielags tilfelle, at organisasjonene også
har vært med på å skape et integrert regionalt fellesskap. Selv om et med-
lem av en lokal organisasjon kan ha et heller perifert forhold til den regio
nale overbygningen, vil vedkommende gjennom dette mellomnivået bli
introdusert for medlemsblad, arrangementer og andre aktiviteter som
presenterer og skaper møteplasser for mennesker fra hele landsdelen. På Agder og i Trøndelag har man hatt flere slike interfylkeskommunale
møteplasser og fellesskap enn i andre deler av landet, noe som har gjort
regionbyggingen, og trolig også fylkessammenslåingen, til en enklere
prosess. Disse undersøkelsene får en også til å stille nye spørsmål. Hvordan
bidro ulike organisasjoner konkret i regionbyggingen? I Agder Historie
lags tilfelle så vi at medlemsbladet Egde ville gjøre medlemmene til egder. Hadde andre organisasjoner like instrumentelle tanker om dette? Hvilke
faktorer avgjorde om man valgte fylkesvis eller fylkesoverskridende
organisering, og hva slags organisasjoner valgte den ene eller andre ret-
ningen? Her kan en tenke seg mange undersøkelser som ikke bare vil
berike den organisasjonshistoriske forskningen, men også gi oss en bedre
forståelse av regionbygging og forholdet mellom territorium og identitet. 120 frivillige organisasjoner og regionbygging frivillige organisasjoner og regionbygging Kilder og litteratur Kilder og litteratur
Aviser
Vestmar
Agderposten
Fædrelandsvennen Litteratur Alsvik, O. (1998). Norsk lokalhistorisk institutt og lokalhistorie i Norge. Norsk
lokalhistorisk institutt. Anderson, B. (2006). Imagined Communities. Reflections on the Origin and Spread of
Nationalism. Verso. (Opprinnelig utgitt 1983) Nationalism. Verso. (Opprinnelig utgitt 1983)
Bausinger, H. (1998). Orientations in Nineteenth-century Tourism. I H.-G. Haupt,
M. G. Müller & S. Woolf (Red.), Regional and National Identities in Europe in
the XIXth and XXth Centuries. European Forum. Kluwer Law International. Bausinger, H. (1998). Orientations in Nineteenth-century Tourism. I H.-G. Haupt, g ,
( 99 )
y
p ,
M. G. Müller & S. Woolf (Red.), Regional and National Identities in Europe in
the XIXth and XXth Centuries. European Forum. Kluwer Law International. Berg, O. T. (2014, 22. mai). Organisasjon. I Store norske leksikon. https://snl.no/
organisasjon Eriksen, A. (1999). Historie, minne, myte. Pax Forlag. Folkestad, B., Christensen, D. A., Strømsnes, K. & Selle, P. (2015). Frivillig innsats i
Noreg 1998–2014. Kva kjenneteikner dei frivillige og kva har endra seg? (Rapport 2015: 4). Senter for forskning på sivilsamfunn og frivillig sektor. http://hdl.handle.net/11250/2445372 Forenings- eller organisasjonshistorie i lokalhistoria. (2020, 1. mars). I Lokalhistoriewiki. https://lokalhistoriewiki.no/wiki/Forenings-eller_
organisasjonshistorie_i_lokalhistoria Hundstad, D. (2012). Historikeren som regionbygger? Et fagkritisk perspektiv på fire
landsdelshistoriske verk. Historisk tidsskrift, 91(1), 37–63. https://www.idunn.no/
ht/2012/01/historikeren_som_regionbygger_-_et_fagkritisk_perspektiv_p Hundstad, D. (2013). Sørlandet – fra terra incognita til sommerferieland. Fire
historiske analyser av regionalitet og regionalisme [PhD-avhandling i historie]. Universitetet i Bergen. Hundstad, D. (2013). Sørlandet – fra terra incognita til sommerferieland. Fire
historiske analyser av regionalitet og regionalisme [PhD-avhandling i historie]. Universitetet i Bergen. Hundstad, D. (2013a). Kappe. I Hundstad 2013. Hundstad, D. (2013a). Kappe. I Hundstad 2013. Hundstad, D. (2013b). Regionbygging i sør. Institusjonaliseringen av Sørlandet som
referanseregion og diskursivt rom. I Hundstad 2013. 121 kapittel 5 Hundstad, D. (2015). Agder Historielag 1914–2014 – En lokalhistorisk reise. Agder
Historielag. Hundstad, D. (2015a, 25. november). Regional bevisstgjøring. Norgeshistorie. https://www.norgeshistorie.no/industrialisering-og-demokrati/artikler/1548-
regional-bevisstgjoring.html (kontrollert 01.03. 2020). Ingskog, E. A. (Red.). (1990). Norske musikkorps: Bd. 1. Notabene Forlag / Norges
musikkorps forbund. Kirkhusmo, A. (1974). Lokalhistorie og framveksten av de frivillige organisasjoner i
Trøndelags-bygdene i tida ca. 1850–1900. Heimen, 16(8), 431–440. Meld. St. 10 (2018–2019). Frivilligheita – sterk, sjølvstendig, mangfaldig – Den statlege
frivilligheitspolitikken. Kulturdepartementet. https://www.regjeringen.no/no/
dokumenter/meld.-st.-10-20182019/id2621384/ Myhre, J. E. (2015, 25. november). Organisasjonssamfunnet vokser fram. Norgeshistorie. https://www.norgeshistorie.no/industrialisering-og-demokrati/
artikler/1511-Organisasjonssamfunnet-vokser-fram.html (kontrollert 01.03. 2020). Onarheim, G. & Selle, P. (1994). Frivillige organisasjoner som etterkrigshistorisk
forskningsfelt [Etterkrigshistorisk register, nr. 17]. LOS-senteret.h Paasi, A. (1986). Litteratur The institutionalization of regions: a theoretical framework for
understanding the emergence of regions and the constitution of regional identity. Fennia – International Journal of Geography, 164(1), 105–146. https://fennia.journal.fi/article/view/9052 Raaum, J. (1988). De frivillige organisasjonenes framvekst og utvikling i Norge. I NOU 1988: 17, Frivillige organisasjoner, s. 239–285. Finansdepartementet. Raaum, J. (1988). De frivillige organisasjonenes framvekst og utvikling i Norge. I NOU 1988: 17, Frivillige organisasjoner, s. 239–285. Finansdepartementet. https://www.regjeringen.no/no/dokumenter/nou-1988-17/id524893/ https://www.regjeringen.no/no/dokumenter/nou-1988-17/id524893/ Scott, G. (2010). Sørlandet. I E. Kristiansen (Red.), Agdesiden. Sørlandet, slik Gabriel Scott, G. (2010). Sørlandet. I E. Kristiansen (Red.), Agdesiden. Sørlandet, slik Gabriel
Scott så det. Gabriel Scott Selskabet. (Opprinnelig utgitt 1937 i W. Werenskiold
[Red.], Norge vårt land: Bd. 2). Scott så det. Gabriel Scott Selskabet. (Opprinnelig utgitt 1937 i W. Werenskiold
[Red.], Norge vårt land: Bd. 2). Seland, B. (2006). Religion på det frie marked. Folkelig pietisme og bedehuskultur. Høyskoleforlaget. Seip, J. A. (1981). Utsikt over Norges historie: Bd. 2. Tidsrommet ca. 1850–1884. Gyldendal. Selle, P. & Hestetun, P. A. (1990). Fylkes- og krinsnivået i organisasjonssamfunnet. Tano. Selle, P. & Øymyr, B. (1995). Frivillig organisering og demokrati. Det frivillige
organisasjonssamfunnet endrer seg. Det Norske Samlaget. Slettan, B. (1998). Agders historie 1840–1920. Ansikt mot sjøen – grunnfeste i jorda. Agder Historielag. Spilling, O. R. & van der Ros, J. (1988). Kultur og regional utvikling. En rapport fra et
forprosjekt om samspillet mellom kultur og regional utvikling i Innlandet (Rapport
13:1988). Østlandsforskning. https://www.ostforsk.no/publikasjoner/kultur-og- 122 frivillige organisasjoner og regionbygging regional-utvikling-en-rapport-fra-et-prosjekt-om-samspillet-mellom-kultur-og-
regional-utvikling-i-innlandet/ regional-utvikling-en-rapport-fra-et-prosjekt-om-samspillet-mellom-kultur-og-
regional-utvikling-i-innlandet/ Smith, L. (2006). Uses of Heritage. Routledge. https://doi.org/10.4324/9780203602263 Steen, S. (1948). De frivillige sammenslutningene og det norske demokrati. Historisk
tidsskrift, 34, 581–600. Try, H. (1985). Assosiasjonsånd og foreningsvekst i Norge. Forskningsoversyn og
perspektiv. Akademisk forlag. Wollebæk, D. & Selle, P. (2002). Det nye organisasjonssamfunnet. Demokrati i
endring. Fagbokforlaget. Østerberg, D. (1997). Sosiologiens nøkkelbegreper og deres opprinnelse. Cappelen. Østerud, Ø. (1994). Hva er nasjonalisme. Universitetsforlaget. 123 Sitering av dette kapitlet: Justvik, N.M. (2020). «Sørlandsmesterskapet». Idrett og idrettsutvikling på
Agder før 1970. I Johnsen, B.E. og Vadum, K. (red.), Grenseløst Agder. Det som skilte og det som bandt
(s. 124–147). Oslo: Cappelen Damm Akademisk. https://doi.org/10.23865/noasp.111
Lisens: CC BY-NC-ND. g
g
3
I idrettshistorien har de olympiske lekene i 1906 blitt kalt «Ekstralekene» siden de kommer uten-
om tur, to og ikke fire år etter foregående OL. Poenget med det hele var å feire 10-årsjubileum for
lekene i 1896. 1
20-årsperioden fra 1965 til 1985 kalles «Idrettsrevolusjonen», både nasjonalt og regionalt. På
Agder flerdobles medlemstallet, gradvis større summer brukes på anleggsutbygging og idretten
profesjonaliseres organisasjonsmessig. I tillegg kommer kompetanse stadig sterkere inn i tre-
ningsarbeidet. Om vippepunktet på 1970-tallet, se forøvrig Justvik 2017 (Kap. 6), 2018 (Kap. 5). l 2
Bø 1956: 208–209; Jensen & Hansen 1956: 501. I det regionsvise flerbindsverket Norges bebyggelse
er forfatterne av oversiktsartiklene om idretten i henholdsvis Aust- og Vest-Agder unisone når
det gjelder å karakterisere Agder som idrettens mørke fastland. Alle tre er godt orientert om
idrettshistorien, og har også vært aktive idrettsmenn. 4
Byklum 1958: 76–77; Line 1932: 49; Olympiastadion 2016; Raustøl 2008 1
20-årsperioden fra 1965 til 1985 kalles «Idrettsrevolusjonen», både nasjonalt og regionalt. På
Agder flerdobles medlemstallet, gradvis større summer brukes på anleggsutbygging og idretten
profesjonaliseres organisasjonsmessig. I tillegg kommer kompetanse stadig sterkere inn i tre-
ningsarbeidet. Om vippepunktet på 1970-tallet, se forøvrig Justvik 2017 (Kap. 6), 2018 (Kap. 5).
2
Bø 1956: 208–209; Jensen & Hansen 1956: 501. I det regionsvise flerbindsverket Norges bebyggelse
er forfatterne av oversiktsartiklene om idretten i henholdsvis Aust- og Vest-Agder unisone når
det gjelder å karakterisere Agder som idrettens mørke fastland Alle tre er godt orientert om kapittel 6
«Sørlandsmesterskapet». Idrett og
idrettsutvikling på Agder før 1970 kapittel 6 Nils M. Justvik Agder før 1970 har blitt karakterisert som idrettens mørke fastland, der
idretten ikke ble tatt særlig høytidelig.1 Det betydde ikke så mye hvor fort
det ble løpt, eller hvor langt det ble hoppet. Vi trener og har det moro, og
litt lærer vi etter hvert, men vi har ingen tradisjoner, het det. Bjørnstjerne
Bjørnsons uttrykk «På det jevne, på det jevne, ikke i det himmelblå» har
blitt benyttet for å beskrive idrettshistorien. Det hevdes riktignok at det
ikke skorter på «menneskemateriellet» når det gjelder å nå toppnivå, og
nettopp det viser de følgende eksemplene på fremragende prestasjoner.2 Midt i mars 1906 møtte 30 turnere i Christiania Turnhall til uttakings-
konkurranse for den 20 mann sterke troppen som skulle delta i de olym-
piske leker i Athen seinere på våren.3 Blant de 20 som tok gull til Norge i
de første moderne olympiske leker, var to sørlendinger: kristiansanderen
Johan L. Stumpf og arendalitten Yngvar Fredriksen.4 3
I idrettshistorien har de olympiske lekene i 1906 blitt kalt «Ekstralekene» siden de kommer uten-
om tur, to og ikke fire år etter foregående OL. Poenget med det hele var å feire 10-årsjubileum for
lekene i 1896. 3
I idrettshistorien har de olympiske lekene i 1906 blitt kalt «Ekstralekene» siden de kommer uten-
om tur, to og ikke fire år etter foregående OL. Poenget med det hele var å feire 10-årsjubileum for
lekene i 1896. 4
Byklum 1958: 76–77; Line 1932: 49; Olympiastadion 2016; Raustøl 2008 124 «sørlandsmesterskapet» Også frolendingen Helge Løvlands OL-gull i tikamp i Antwerpen
i 1920 var et høydepunkt. Herefossingen Reidar Andreassen vant to
norgesmesterskap på femmila på ski i 1958 og 1960, som den eneste fram
til i dag. I 1960 ble han også norgesmester i friidrett på 10 000 meter bane-
løp. Reidar Andreassen og Helge Løvland er de to eneste fra Agder som
har mottatt en av norsk idretts høyeste utmerkelser: Egebergs ærespris,
prisen for allsidig idrett. I 1960 ble Ole Tom Nord fra Øyslebø første og
eneste norgesmester i hopp fra Agder, endatil som juniorhopper. Som «sørlandsmesterskap» betraktet tyder disse idrettsprestasjonene
på at Aust-Agder gikk av med seieren over nabofylket i vest. Det sentrale
spørsmålet i dette kapitlet er todelt. 5
Den demografiske utviklingen på Agder er interessant ved at de to fylkene i 1870 var like store
med hensyn til innbyggertall – omkring 75 000. Hundre år senere var det 45 000 flere vestegder.
Antall austegder hadde stått på stedet hvil. kapittel 6
«Sørlandsmesterskapet». Idrett og
idrettsutvikling på Agder før 1970 For det første, hvordan var det mulig
for disse idrettsutøverene å nå så langt som de gjorde i en periode da
idretten hadde relativt liten oppslutning i regionen og rammebetingel-
sene var dårlige for organisert idrett? En hovedpåstand er at den orga-
niserte idrettsbevegelsen i regionen hadde enkelte særtrekk – som små,
tette miljøer og flere allsidige idrettsutøvere i denne perioden. For det andre: vi kan observere at det fantes ulikheter mellom de to
fylkene Aust- og Vest-Agder. Hvorfor var de idrettslige miljøene i øst mer
vitale enn i vest, selv om Arendal aldri ble en så sentral og viktig idrettsby
i Aust-Agder som Kristiansand ble i Vest-Agder?5 En forklaring som
utforskes er hvorvidt den pietistiske vekkelsesbevegelsen, som hadde sin
storhetstid i hundreåret fra 1870, slo sterkere inn i vestlige deler av Agder
når det gjaldt motstand mot idretten. 6
Try 1969: 146ff f
7
Wold 1959: 7–8 Pionerfase i byene At de østlige delene av regionen tidlig markerte seg på idrettens område,
kan ha sammenheng med at det også var der idretten først ble organisert,
men da først og fremst som et byfenomen. I 1906, da det første olympiske
gullet ble brakt både til Arendal og Kristiansand, hadde «Turnvater» 125 kapittel 6 Joseph Stockinger vært ute av historien i tre år. Uten ham, intet gull til
Agder i 1906. Østerrikeren og bokbindersvennen Stockinger kom til Kris-
tiania i 1854, og dannet der den første turnforeningen i landet, før han
høsten 1856 etablerte seg i Arendal. Tre kvart år gikk, og landets andre
turnforening ble stiftet i Arendal 17. mai 1857. Det var en veloverveid beslutning å flytte til Arendal, som på den tiden
gjennomlevde sin storhetstid. Arendal var landets største sjøfartsby med
stor rikdom, riktignok fordelt på få hender.6 Stockinger ble boende i Aren-
dal livet ut, utøvet sitt yrke som bokbindermester, giftet seg og fikk flere
barn. En av døtrene giftet seg med slaktermester Johan L. Stumpf, gull-
medaljøren fra Kristiansands Turnforening, enda en i rekken av turnfore-
ninger Stockinger etablerte eller var sterkt medvirkende til å få etablert. Stockinger tillegges mye av æren for at turnbevegelsen slo rot i Norge
flere år før den nasjonale idrettsbevegelsen, Centralforeningen for Udbre-
delse af Legemsøvelser og Vaabenbrug, ble dannet i 1861. Det er nærmest
mytiske dimensjoner over Joseph Stockinger, som i turnkretser har fått
tittelen «Turnsagens Fader og Forkjæmper». I Trondheim Turnforenings
100-årsskrift, en turnforening Stockinger aldri hadde noen befatning
med, heter det om ham: Ethvert virkelig eventyr har sin prins eller prinsesse. Eventyrprinsen i norsk
turnidretts «det var en gang», satte som alle andre eventyrprinser det mål å
vinne det halve kongerike. En fremmed fugl fra et fremmed land, en farende
bokbindersvenn [...] som slo seg ned i et land langt mot nord hvor det så ut til å
være godt å bo og bygge, og som sådde frø som spirte og grodde og ble til norsk
turnidrett [...] startet ved sin innsats en kjedereaksjon som bredte seg ut over
det ganske land [...]. Eventyret om østerrikeren Joseph Stockinger er eventyret
om prinsen som vant det hele kongerike. Han er såmannen i norsk turnidrett,
rydningsmannen for all norsk idrett.7 I tillegg til å danne turnforeninger var Stockinger opptatt av organisasjon
– kontakt og samvirke mellom turnforeningene. 8
Stockinger 1903. Generalberetningen er limt inn over to sider som ikke er paginert. Paginerin-
gen før og etter er 136 og 137.
9
Byklum 1958: 12–13 9
Byklum 1958: 12–13 8
Stockinger 1903. Generalberetningen er limt inn over to sider som ikke er paginert. Paginerin-
gen før og etter er 136 og 137.
B kl
8 9
Byklum 1958: 12–13 Pionerfase i byene Kort tid etter ankomst 126 «sørlandsmesterskapet» til Arendal tok han kontakt med Christiania Turnforening for at denne
foreningen skulle sørge for kontakt mellom turnforeningene i landet. Resultatet av dette ble «Generalberetning om de forskjellige Turnfore-
ningers Tilstand i Norge, afgiven af Centralforeningen i Christiania»,
datert juni 1858. Litt over et år etter dannelsen av turnforeningen i Arendal
fantes det bare én annen forening på Agder: «Næs Værks Turnforening er
stiftet 6te November 1857 og tæller 20 medlemmer.»8 Det skulle komme
langt flere, deriblant Kristiansands Turnforening høsten 1858, på direkte
inspirasjon fra Arendal.9 Organiseringen av turnbevegelsen regionalt og nasjonalt fikk først fart på
1880-tallet. Med Stockinger som drivkraft ble Norges første særkrets for
en idrettsgren dannet – Agdesidens Turnkrets – i Risør i 1883, samtidig 127 kapittel 6 med Risørs Turnforenings tilblivelse.10 Samme år ble også en nasjonal
turnorganisasjon forsøkt dannet, dog uten hell. Noen år seinere ble det
gjort et nytt forsøk, som også strandet. I 1890 kom en varig, nasjonal
særkretsorganisasjon på plass, den første i Norge. I forbindelse med de
to første var Joseph Stockinger en sentral person, og når det gjelder den
siste varige – Det norske Turn- og Gymnastikforbund – var han den store
formidler til alle turninteresserte. Stockinger var redaktør for det eneste
nasjonale idrettstidsskriftet som fantes mellom 1889 og 1993 – Norske
Turnnotitser.11 Våren 1890 meldes følgende i bladet for den andre nasjo-
nale turnfest, som skulle arrangeres i Bergen: «Oprettelsen af et norsk
Turnforbund bliver ifølge Programmet for 2den norske nasjonale Turn-
fest i Bergen et af de Foretagender til Turnsagens Fremme, der skal fuld-
føres under denne Fest.»12 Historikeren Hans Try opererer med tre bølger av foreningsdannelser
i sin beskrivelse av organisasjonsutviklingen på 1800-tallet. Den første
bølgen kom i 1840-årene, med dannelse av misjons- og måteholdsfore-
ninger. Dominansen av de bedrestilte i samfunnet var tydelig i denne
første bølgens foreninger. Stockinger kom til Norge og etablerte de første
turnforeningene mellom den første og andre bølgen – den siste fra slutten
av 1860-tallet og inn på 1870-tallet. Når det gjelder den sosiale sammen-
setning i de første turnforeningene, så samsvarer dette med dominansen
av de bedrestilte fra den første bølgen. Som vi skal se i fortsettelsen, var
Stockinger opptatt av at også de lavere klasser skulle delta i turnøvelsene. Hvor sterkt han lyktes i dette, kan absolutt diskuteres. Dette er et typisk
trekk ved den andre bølgen som Try skisserer. 10
Justvik 2018: 24
11
Første utgave av bladet er datert juli 1889, der det nevnes at «det alle norske Idrætter omfat-
tende, smukt udstyrede og altid interessante Organ ‘Norsk Idrætsblad’» måtte gå inn etter sju år.
I desember 1893 kom siste nummer av bladet, og det nevnes at den vesentligste årsak var at Norsk
Idrettsblad var igangsatt. 12
Norske Turnnotitser, mars 1890, 2(3), 33 13
Try 1979: 432ff
14
Justvik 2018: 20
15
Norsk idrætsblad, nr. 45, 11.9.1881
16
Justvik 2018: 33
17
Dokkedal 2011: 6–7
18
Stockinger 1907: 76 Pionerfase i byene I begge de to første bølgene
finner vi større sammenslutninger av foreninger, Thranebevegelsen og
Bondevennbevegelsen, som kan ses som paralleller til Stockingers dan-
nelse av både regionale og nasjonale bevegelser. Begge de nevnte beve-
gelsene hadde sine blad, som også Stockinger ga ut, omkring tiden for 128 «sørlandsmesterskapet» dannelsen av det første landsdekkende turnforbundet. Denne dannelsen
er knyttet til Trys tredje bølge i 1880-årene.13 Turn var i utgangspunktet ikke bare legemsøvelser. Øvelsene var del
av et større hele, der utflukter og turnfester med sang og musikk hadde
en viktig plass. Det ble lagt vekt på naturglede, på sosialt brorskap og lik-
het, nasjonal enhet og offervilje.14 Stockinger var opptatt av at alle skulle
med. Derfor ivret han helt fra starten for at både barn, kvinner og menn
skulle drive med turn og andre idretter. Det skortet ofte på instruktører
i turnforeningene, og da måtte ofte kvinner og barn lide for dette. Først
fra omkring 1890 ble det god regularitet i turnidretten for kvinnene, ikke
bare i Arendals turnforening. Selv om det som oftest i Stockingers levetid var de bedrestilte som drev
med idrett i turnforeningene, ønsket han å utbre idrettsinteressen til de
mindre bemidlede. Høsten 1881 dro en kontingent turnere fra Arendal
til Austre Moland for å utfordre vernepliktig ungdom «for muligens
sammen med turnerne at forsøke sig i forskjellige legemsfærdigheder». 17 turnere og 11 landboere deltok i øvelsene, som bestod av en rekke gym-
nastikkøvelser samt friidrettsøvelsene høyde, lengde og kulestøt.15 Et sentralt trekk ved turnforeningene var at de ofte ble paraplyorga-
nisasjoner for en rekke forskjellige idrettsøvelser. Friidrettsøvelsene var,
som nevnt ovenfor, en del av turningen, men allerede i 1862 kom fek-
ting på programmet i Arendals Turnforening.16 Kappgang var også en
av aktivitetene, og siden hadde skøyting sitt utgangspunkt i turnfore-
ningen i Arendal.17 Den første særidrettsklubben for skiidrett ble dannet
under turnforeningsparaplyen i Arendal, Arendals Skiklubb, og Joseph
Stockinger var initiativtaker. Klubben ble stiftet i 1881, og første aktivitet
i klubben var en utflukt med en hoppkonkurranse. Så å si alle falt, «paa
gamle Stockinger nær, der for første gang, i sit 53 Aar, var ude på ski».18 Arendals Turnforening hadde aldri fotball på programmet. Som
vi skal se var det Froland og to utdanningssøkende derfra som hentet 129 kapittel 6 fotballspillet til Aust-Agder, noen år inn på 1900-tallet. 19
Justvik 2017: 63
20
Sitatet er hentet fra overskriften til en artikkel om Helge Løvland i Norsk Idrætsblad og Sport
1920, Julenummeret: 13.
21
Løvland 1971: 20. Bryteren Carl Norbeck ble på grunn av sin store innsats for brytesporten i
Ørnulf klubbens første æresmedlem. Jacobsen 1946: 16 Pionerfase i byene Vest-Agder var
noe tidligere ute, på begynnelsen av 1890-tallet, med Håkon Frøstrup
som formidler av fotballspillet inn i Kristiansands Turnforening. Etter
en periode i England, der han drev turnskole, hadde han blitt kjent med
«Association Football». I et brev til turnforeningen, der han forklarer
relativt detaljert om spillet, heter det: «Jeg tillader mig herved at henlede
den ærede turnforenings bestyrelses opmerksomhed paa et i England
meget yndet spil, kaldet ‘Football’».19 Breddeidrett på bygdene Pionerfasen var først og fremst et byfenomen. I Aust-Agder kjenneteg-
nes den videre utviklingen av idrettsbevegelsen av små, kraftfulle miljøer
på bygdene, som ofte viste seg å være svært seiglivede. Dette aspektet er
tydeligere i øst enn i vest, der idrettsbevegelsen i større grad ble sentrali-
sert rundt Kristiansand. Men pionerfasen var også orientert mot bredde,
og dette ble et vedvarende aspekt også ved bygdeidretten. Et eksempel på dette er Helge Andreas Løvland, gjerne kjent som «All
round mændenes verdensmester».20 I 1970, da Løvland var 80 år, ga han i
et tilbakeblikk en beskrivelse av idrettens kår på bygdene i Agder i hans
oppvekst omkring århundreskiftet. Organisert idrett fantes ikke på byg-
dene, bare i byene. Innen friidrett, Løvlands egen idrettsgren, fantes det
ingen instruksjon. Guttene møttes «på løkka», drev med kappløfting, litt
hopping og løping. Bryteren Karl Norbeck var idealet, for øvrig medlem
av Ørnulf, samme klubb som Løvland kom til å tilhøre i hovedstaden da
han flyttet dit i 1911.21 Dette til tross, det var av den 20 år eldre barnevandreren og åsdølen
Bjørgulv Torsland som hadde lært ham mye om trening. Unge Løvland
trodde blindt på Torsland – «den beste treneren min» – og fikk fra 12-års-
alderen en sekk med stein bundet fast til ryggen og trente, pløyde eller 130 «sørlandsmesterskapet» kjørte hestevandring sent og tidlig. Videre drev de to med allsidig trening:
«ryggtak og armtak, fingerkrok og krokbein, håndtak og strakarmløf-
ting, ryggløft, eller rettere sagt kast, høyde- og lengdehopp samt ‘jamsis-
hopp’ og løp». Med oppvekst på bygda hadde Helge Løvland også linjer til to andre
bevegelser med idrett på programmet, som begge er karakteristiske
for idretten i denne fasen. For det første var han med fra relativt tidlig
alder i et av skytterlagene i Froland.22 Helt siden dannelsen av den første
nasjonale idrettsbevegelsen i 1861, Centralforeningen for Legemsøvelser
og Vaabenbrug, som hadde en unionskonflikt som årsak til dannelsen,
var skytterlagene den dominerende grupperingen. Å utvikle og utdanne
fedrelandsforsvarere, som var et overordnet mål, ble riktignok sett på
som noe mer enn bare å danne skytterlag og bidra til å utvikle skyte-
ferdigheter. 22
Dannevig 1979: 588. Bilde av Helge Løvland med gevær, sammen med skytterlagskamerater i
Froland.
23
Centralforeningens Årsberetning 1862: V, 1869: 22–23
24
Byklum 1958: 18ff; Stockinger 1907: 10ff
25
I Centralforeningens statutter fra 1861 heter det: «d. sætte sig i Forbindelse med de allerede
oprettede Gymnastik- og Vaabenøvelses-Foreninger, samt efter Omstendigheder at yde dem
anden Bistand.»
Centralforeningens Årsberetning 1861: Ingen paginering, 1882: 50–51 22
Dannevig 1979: 588. Bilde av Helge Løvland med gevær, sammen med skytterlagskamerater i
Froland.
Å 23
Centralforeningens Årsberetning 1862: V, 1869: 22–23ff Breddeidrett på bygdene Skiidrett og innføring av fysisk fostring i skolen, ofte omtalt
som «gymnastiksagen», ble sett på som viktig for framtidige forsvarere av
landet.23 Nærheten mellom turnbevegelsen og skyttervesenet var i peri-
oder sterk, med både samarbeid og endatil dannelse av en felles organi-
sasjon for turnforeninger og skytterlag, i Arendal som i Kristiansand.24
Helt fra starten av hadde Centralforeningen intensjon om å sette seg i
forbindelse med turnforeningene for å støtte disse. Like inn på 1880-tallet
finnes en oversikt over hvilke idrettsforeninger som hadde sluttet seg til
Centralforeningen: Av 21 foreninger var det fem fra Aust-Agder, deriblant
turnforeningen, roklubben og skiklubben fra Arendal. Bare én forening
var fra Vest-Agder, Kristiansandsklubben Oddersjaa.25 Fra 1893 skiltes idrettsbevegelsens og skytterlagsbevegelsens veier ved at
de to dannet separate nasjonale bevegelser, henholdsvis Centralforenin-
gen for Idrett og Det frivillige Skyttervesen. Inn i det nye århundret
arbeidet Centralforeningen hardt for at idretten også skulle utbre seg til 131 kapittel 6 bygdeherredene. Ledelsen hadde innsett, som Helge Løvland, at idretten
omkring 1900 var et byfenomen. Den første idrettsforeningen på bygda
i Aust-Agder kom i 1895, med Dristug i Åmli. I Froland ble idrettslaget
først dannet i 1916. Målet å utvikle og dyktiggjøre fedrelandsforsvarere
stod fast, og dermed var allsidig idrettsaktivitet viktig for alle områder
av landet. Ikke minst ble dette viktig for den unge, selvstendige nasjonen
etter 1905. Centralforeningen sendte ut idrettsmisjonærer til hele landet,
Agder inkludert. Kaptein Henrik Angell tok i 1906 for seg tolv steder fra Valle til Mosby,
i tillegg til fire steder på Listalandet, altså primært de midtre og vest-
lige delene av regionen. Han opplevde at interessen for idrett var stor,
men i de øverste bygdene i Setesdal fikk han syn for «en idræt, som er
saa god og smuk, at den erstatter næsten al anden, og det er ‘gangaren’
og ‘hallingen’. I de nationale danse har man den herligste gymnastik og
plastik». Angell noterte også momenter som kunne bidra til å bremse
idrettsgleden. Han registrerte at emigrasjonen fra landsdelen gjorde store
innhogg i målgruppen – ungdommen, og antok at nærmere halvparten
av vernepliktig ungdom forlot bygdene. Dette hemmet utviklingen av
idretten, mente Angell, som opplevde «den i enkelte bygder graserende
pietisme [...] den slaar idræt som al anden ytring af sund, naturlig livs-
glæde ned». f
27
Centralforeningens Årbok 1904: 83ff. Grimeland har en flere siders artikkel om temaet «Idræts
arbeidet og ungdomslagene» der han utdyper sitt synspunkt om hvorfor idrettsarbeidet må tas
opp av ungdomslagene. 26
Centralforeningens Årbok 1906: 112fff Breddeidrett på bygdene På et av stedene hadde spenningen mellom det frilynte og
det kristne ungdomslaget vært så sterk at den lokale sersjant, etter alt å
dømme utdannet på Underoffiserskolen i Kristiansand, ikke våget å bidra
til gymnastikkvelder.26 En noe tidligere rapport vitner om at idretten allerede på den tiden
var sterkere etablert i bygdene i øst. To år før kaptein Angell foretok sin
reise, hadde skolebestyrer Bertel A. Grimeland foretatt en tilsvarende
reise, men denne gang også i store deler av Nedenes amt.27 Idrettsengasje-
mentet i denne delen av Agder var større enn det Angell hadde avdekket,
ikke minst organisatorisk. I forbindelse med sitt besøk i Arendal hadde
Grimeland motivert for dannelse av et «amtsidrætsforbund», noe han 132 «sørlandsmesterskapet» mente var realistisk i nær framtid. Det gikk enda 15 år før noe slikt ble
opprettet, og da under navnet Aust-Agder Distriktslag for Idrett.28 Ungdomslagene kom til å få stor betydning for utbredelsen av idretten
på bygdene. Grimeland hadde vært i kontakt med frilynte ungdomslag
og «idrætsinteresserede mænd» på flere steder i amtet. I rapporten han
skrev etter reisen, nevner han i kursiv «idrætsinteresserede lærere». I fort-
settelsen følger: Det gjælder nemlig idrætssagen mere end nogen anden sag, at har man vundet
lærerne, saa har man ogsaa ungdommen og fremtiden. I skolen, samt i ung-
domslagene, hvor lærerne som regel er de ledende, maa forstaaelsen for og lys-
ten til idræt vækkes. Lærerne kan ogsaa give praktisk veiledning, og de er ikke
ræd for at ofre tid og arbeide, hvis de interesserer sig for en sag. Karakteristisk
nok er de idrætsinteresserede formænd i de ovenfor nævnte ungdomsforbund
– samtlige lærere.29 Grimeland var i Froland i 1904, og derfor taler mye for at Anders Løvland,
Helge Løvlands far, var en av disse idrettsinteresserte lærere og formenn
som Grimeland hadde hatt kontakt med. Anders Løvland var lærer, utek-
saminert fra Holt seminar før læreanstalten ble flyttet til Kristiansand
i 1877, og initiativtaker til og formann i ungdomslaget i Froland i mer
enn 20 år fra 1900. Helge Løvlands eldste bror, Olav, var sammen med
kameraten Anders Danielsen pionér for introduksjonen av fotballspillet i
Nedenes amt like inn på 1900-tallet.30 Ungdomslagene tok imot budskapet fra idrettsmisjonærene Angell og
Grimeland. De to fylkesorganisasjonene av frilynte ungdomslag meldte
seg kollektivt inn i Centralforeningen for udbredelse av Idræt. 28
Justvik 2018: 59–60
29
Centralforeningens Årbok 1904: 77ff
30
Dannevig 1979: 595–596
31
Centralforeningens Årbok 1906: 196 32
Lande 1968: 26
33
Repstad 2002: 99
34
Slettan 1992: 166ff, 27ff, 127
35
Seland & Aagedal 2008: 37ff
36
Se Justvik 2012 for holdninger til idrett på Agder 1945–2000. Det skal ikke underslås at min
empiri i stor grad er knyttet til Kristiansands-området. f
36
Se Justvik 2012 for holdninger til idrett på Agder 1945–2000. Det skal ikke underslås at min
empiri i stor grad er knyttet til Kristiansands-området. 35
Seland & Aagedal 2008: 37ff Breddeidrett på bygdene Fram til
reorganiseringen av idrettsbevegelsen i 1919, med dannelse av fylkesvise
organisasjoner – Aust- og Vest-Agder Distriktslag for Idrett – utgjorde
ungdomslagene majoriteten, med 36 foreninger og nærmere 2000 med-
lemmer.31 Vest-Agder Ungdomsforbund fikk endatil inn i sine statutter at 133 kapittel 6 det skulle arbeides for utbredelse av idrett.32 Aust-Agder Ungdomsforbund
arbeidet også for idretten, og i 1910, da forbundet avholdt fylkesstevne på
Herefoss, var en idrettskonkurranse del av programmet. 5 av 15 idretts
utøvere ble premiert; den beste av disse var 20-åringen Helge Løvland. Her kan en kanskje også se noe av forklaringen på den ulike utviklin-
gen øst og vest på Agder. Spenningen mellom de frilynte og de kristelige
ungdomslagene, som Angell påpekte, aktualiserer spenningene og stri-
den den lavkirkelige vekkelsesbevegelsen skapte mange steder på Agder
gjennom en hundreårsperiode fram til 1970-tallet. Perioden på 100 år
karakteriseres av religionssosiologen Pål Repstad som «den lekmanns
baserte vekkelseskristendommens gyldne hundreår i lokalsamfunnene
på Agder».33 Historikeren Bjørn Slettan, som har studert vekkelsene på
Agder på 1800-tallet, forteller at forsøket på å skape harmoni mellom
pietistene og de frilynte på Agder «mislyktes fullstendig. Istedetfor til-
nærming ble det polarisering».34 Historikeren Bjørg Seland har funnet
tre større vekkelsesbølger i hundreåret mellom 1870 og 1970: den første
omkring 1870, den andre omkring århundreskiftet og den tredje i mel-
lomkrigstiden.35 Den fjerde vekkelsesbølgen kom aldri, men den negative
holdningen til idrett holdt seg for en stor del i de vekkelsesorienterte og
pietistiske miljøene fram til 1970, og er en vesentlig årsak til idrettens
svake stilling på Agder fram til 1970-årene. I min doktoravhandling fra
2012 har jeg argumentert for nettopp dette. I de lavkirkelige miljøene
på Agder var det for det første en sterk skepsis til idretten, fordi den i
stor grad la sine arrangementer til søndagene. Videre var idrettsmiljøene
ansett for å utgjøre en upassende og til dels farlig innflytelse på kristne
ungdommer, der bannskap hørtes, alkohol ble benyttet og misbrukt, og
dansen gikk over tilje til langt på natt, som det heter om fester fra idretts
miljøet. Det farligste ved idretten var nok at den kunne engasjere ung-
dommene i så stor grad at den kristne tro var i fare.36 134 «sørlandsmesterskapet» Det er hevet over tvil at spenningene mellom de kristne miljøene
og de mer frilynte miljøene utover på 1900-tallet kunne være strie og
sterke på Agder. Breddeidrett på bygdene Likevel, spenningene varierte noe fra bygdesamfunn til
bygdesamfunn, og det kan se ut til at de var sterkere i Vest-Agder enn
i Aust-Agder. Kaptein Angell registrerte den «graserende pietismen» på
grensa mellom fylkene og lengre vestover. Grimeland, som holdt seg i
Aust-Agder, nevner ikke fenomenet overhodet. 37
Braadland, 2009; Stubhaug 2014: 474, 428
38
Wivestad 1989: 122–123 Gymnastikkundervisning i øst og vest Utdanningsinstitusjonene på Agder har også hatt mye å si for utbredelse
av idretten, i særlig grad ved at det tidlig ble lagt vekt på gymnastikk. I øst var den i stor grad knyttet til seminaret i Holt. I vest var det under
offisersutdannelsen i Kristiansand som sto i sentrum. På dette feltet ble
sistnevnte etter hvert et sterkere sentrum. Dette bidro i sin tur til å for-
sterke forskjellene mellom en sentralisert idrett i vest og en mer desentra-
lisert idrettsbevegelse, basert på små, kraftfulle miljøer, i øst. I 1839 ble Christianssands Stiftsseminarium (Holt seminar) oppret-
tet på Holt prestegård. Det var minst tre årsaker til denne plasseringen:
Prestegården hadde velegnede lokaler for virksomheten, den lokale prest
Andreas Faye var dyktig både som lærer, folkeminnegransker og histori-
ker, og i tillegg bodde den lærde Jacob Aall i nærheten.37 Faye var styrer for skolen, og allerede i den første årsberetningen
gjorde han oppmerksom på en sentral mangel ved studentenes liv: for lite
bevegelse og mosjon. Ingen av lærerne ønsket å drive med gymnastikk
undervisning, så Faye ba derfor i den første årsrapporten myndighetene
om lov til å anskaffe en klyvemaskin, eller å anlegge en kjeglebane. Dette
var noe han hadde sett i Tyskland, antagelig på begynnelsen av 1830-tal-
let, da han var på en lengre dannelsesreise i Sentral-Europa som var
bekostet av ham selv. I 1851 ble seminarlærer Andreas Feragen «mot en
liten betaling pålagt å drive gymnastikk med elevene i sommertiden». Feragen ble den første gymnastikklæreren i seminarets historie.38 Vi må 135 kapittel 6 anta at dette må ha hatt en viss innvirkning på seminaristene. Selv om far
til Helge Løvland aldri ble noen idrettsmann, var han under innflytelse
av Feragen i årene han gikk på seminaret, 1871–73, etter all sannsynlighet
en av mange. Ovenfor har vi sett at lærerne var viktige for å få integrert
idrett i ungdomslagene. Verken Faye eller Feragen har fått pionerstempel
for å være tidlig ute med å introdusere gymnastikk i seminarene. Det har
derimot teologen, skolemannen og politikeren Nils Hertzberg (1827–1911)
fått. Han virket nærmere 20 år etter Faye og Feragen.39 På slutten av 1850-tallet ble det stiftet to turnforeninger innenfor Holt
sogn, Nes Verk og Tvedestrands turnforeninger. Dette var helt i starten
av Stockinger-perioden. Som vi har sett ovenfor var turnforeningene en
konsekvens av Joseph Stockingers arbeid for å utbre turn. 39
Pioneren for kroppsøvingsfaget var Nils Hertzberg (1827–1911), teolog, skolemann og politiker.
Han var etter teologisk embetseksamen på begynnelsen av 1850-tallet lærer på Krigsskolen, for
så å flytte til Asker seminar fra 1860 til 1867. Fram til 1873 var han bestyrer for Hamar Seminar.
I denne tiden arbeidet han sterkt for gymnastikkfaget i seminarene. I 1865 tok han et kurs ved
forløperen for Den gymnastiske Centralskole, og etter dette overtok han gymnastikkunder-
visningen på seminaret der han arbeidet. Han fikk innredet et skur til gymnastikksal og anskaf-
fet apparater, rifler og eksersisgevær.
40
Norsk Skytter-Tidende 15. mars 1864. For mer om dette spesielle skiløpet, se Justvik 2017: 47–48.
41
Leewy 1980: 160 41
Leewy 1980: 160 Gymnastikkundervisning i øst og vest I 1877 var det
slutt for seminaret i Holt, som ble flyttet til stiftsstaden Kristiansand. Men
dette var ikke den eneste viktige utdanningsinstitusjonen i Kristiansand. For den idrettslige aktivitet i stiftsstaden, men også for idretten på Agder
og i Telemark, betydde kanskje Underoffiserskolen vel så mye. I 1859 kom Josef Frantz Oscar Wergeland tilbake til sin fødeby som
offiser. I 1868 ble han sjef for infanteribrigaden i byen. Han avsluttet kar-
rieren som generalmajor. I Kristiansand utfoldet han et mangslungent
arbeid innenfor byforskjønnelse, idrett og lokalpolitikk. Da Central-
foreningen ble stiftet i 1861, var Wergeland en viktig pådriver for etable-
ringen av Kristiansand Skytterlag. Gjennom sine publikasjoner, deriblant
to bøker om skiløping, fikk han stor betydning for både sivil og militær
skiløping på nasjonalt plan. I Kristiansand arrangerte han skiløp for sol-
dater og sivile, og ble dermed en viktig pådriver for skisport i området.40
Etter et skirenn på Sødal skal Wergeland ha arrangert fakkeltog for nær-
mere 100 skiløpere på en islagt Otra ned til byen – «et praktfullt skue».41
Han var en sterk pådriver for etableringen av Kristiansands ski- og 136 «sørlandsmesterskapet» skøiteklubb Oddersjaa, verdens antatt eldste skiklubb, og han ble æres-
medlem av både Oddersjaa og Kristiansands Turnforening.42 Wergelands betydning i idrettslig sammenheng kom gjennom de for-
skjellige konkurransene han arrangerte. Som nevnt var det både soldater,
elever ved Underoffiserskolen og sivile som deltok i disse. Flere av solda-
tene og de uteksaminerte fra Underoffiserskolen dro til sine hjembygder
og ble igangsettere for idrett. Den første formannen i Vegårshei Idrettslag,
etablert i 1902, var en av de uteksaminerte fra Underoffiserskolen.43 Oven-
for har vi sett at kaptein Angell omtalte sersjanter, etter alt å dømme med
bakgrunn fra verneplikt i Kristiansand eller som elever ved Underoffiser-
skolen, som ikke våget å sette i gang gymnastikkinstruksjon av hensyn
til det kristelige ungdomslaget.44 De nevnte eksemplene kjennetegnes av
at soldatene og elevene ved Underoffiserskolen dro hjem etter endt ekser-
sis eller skole. I mellomkrigstiden ser vi en annen tendens som er særlig
tydelig for elevene ved Underoffiserskolen. Flere av disse – store idretts
talenter – returnerte ikke hjem etter endt skole. 42
Steen 1948: 287. Det kan argumenteres for at Trysilgutten er landets eldste ved at den ble stiftet
i 1861, men da er ikke kriteriet at klubben har en sammenhengende historie uten avbrudd. Det
kan derimot Oddersjaa skilte med.
d l 44
Centralforeningens Årbok 1906: 113 45
Mye i dette avsnittet bygger på Justvik 2018: 108ff 43
Songedal 2002 42
Steen 1948: 287. Det kan argumenteres for at Trysilgutten er landets eldste ved at den ble stiftet
i 1861, men da er ikke kriteriet at klubben har en sammenhengende historie uten avbrudd. Det
kan derimot Oddersjaa skilte med.
43
Songedal 2002
44
Centralforeningens Årbok 1906: 113
45
Mye i dette avsnittet bygger på Justvik 2018: 108ff Den menneskelige faktoren Rammebetingelsene for idretten var lenge dårlige på Agder. Desto vik-
tigere var det menneskelige aspektet ved idrettsbevegelsen – evnen til
å kunne inspirere og motivere. 45 I 1911 hadde Helge Løvland dratt til
hovedstaden for å ta utdannelse som etter hvert ble spesialisert mot gym-
nastikk. Utdannelsen dannet utgangspunkt for en fremragende karriere
som idrettsutøver, der han først markerte seg nasjonalt og deretter inter-
nasjonalt. I 1920 kulminerte dette med at han tok OL-gull i tikamp. Men 137 kapittel 6 Løvland glemte aldri hvor han kom fra, og så lenge han levde, var han en
viktig inspirator innen idretten i Aust-Agder.46 Da slåtten var unnagjort på Mjølhus sommeren 1916, samlet den kjente idretts-
utøveren Helge Løvland en del unggutter på et jorde og startet instruksjon i
friidrett. Det samlet seg snart en flokk interessert ungdom rundt ham, og disse
ble samme høst enige om å danne Froland Idrettslag.47 Og både inspirasjon og godt «menneskemateriell» var det
behov for.48 Rammebetingelsene for idrett var jevnt over
svært dårlige. Det fantes ingen idrettsplass innenfor fylket
som kunne benyttes til kretsmesterskap i friidrett de tre
første årene på 1920-tallet, så derfor måtte idrettsplassen i
Kragerø benyttes. Først i 1923, da «Særkrets for Fri idræt»
ble dannet, var Lyngmyr ved Tvedestrand opparbeidet og
kunne benyttes. Det registreres at Holt sogn spilte en viktig
rolle for utviklingen av idrett i mellomkrigsårene, selv om
lærerseminaret for lengst var flyttet til Kristiansand. Utover på 1920-tallet sleit den nevnte særkretsen med
et problem. Flere av de beste idrettsutøverne flyttet ut av
Aust-Agder og begynte som elever på Underoffiserskolen. Olav Måmoen og Sigurd Dahle, fra henholdsvis Åmli og
Søndeled, var en del av friidrettsmiljøet i Underoffiserenes
Idrettslag og deltok i 1925 i Sørlandsmesterskapet. De to var
nærmest et kretslag alene, og Aust-Agder Friidrettskrets’
historiker konkluderte med følgende: «Vi slo oss sjøl!»49 Både Måmoen og
Dahle meldte overgang til Kristiansand Idrettsforening, og de nådde opp til
nasjonalt nivå i sine øvelser. Måmoen ble norgesmester i tikamp i 1927, og
Sigurd Dahle, også allsidig som Måmoen, fikk sitt norgesmesterskap i kule. Før NM i 1934 ble det stilt spørsmål ved tyngden på kulene som Sigurd Dahle
benyttet. I et par konkurranser lokalt hjemme i Søndeled oppnådde han
Olav Måmoen fra Åmli i
underoffisersuniform. I 1927 ble
han norgesmester i ti-kamp – for
Kristiansand Idrettsforening. Olav Måmoen fra Åmli i
underoffisersuniform. I 1927 ble
han norgesmester i ti-kamp – for
Kristiansand Idrettsforening. 46
Justvik 2018: 108, 94
47
Østreim 2016: 11
48
Bø 1956: 209
49
Fredriksen 1998: 23 Den menneskelige faktoren Og både inspirasjon og godt «menneskemateriell» var det
behov for.48 Rammebetingelsene for idrett var jevnt over
svært dårlige. Det fantes ingen idrettsplass innenfor fylket
som kunne benyttes til kretsmesterskap i friidrett de tre
første årene på 1920-tallet, så derfor måtte idrettsplassen i
Kragerø benyttes. Først i 1923, da «Særkrets for Fri idræt»
ble dannet, var Lyngmyr ved Tvedestrand opparbeidet og
kunne benyttes. Det registreres at Holt sogn spilte en viktig
rolle for utviklingen av idrett i mellomkrigsårene, selv om
lærerseminaret for lengst var flyttet til Kristiansand. Utover på 1920-tallet sleit den nevnte særkretsen med
et problem. Flere av de beste idrettsutøverne flyttet ut av
Aust-Agder og begynte som elever på Underoffiserskolen. Olav Måmoen og Sigurd Dahle, fra henholdsvis Åmli og
Søndeled, var en del av friidrettsmiljøet i Underoffiserenes
Idrettslag og deltok i 1925 i Sørlandsmesterskapet. De to var
nærmest et kretslag alene, og Aust-Agder Friidrettskrets’
historiker konkluderte med følgende: «Vi slo oss sjøl!»49 Både Måmoen og
Dahle meldte overgang til Kristiansand Idrettsforening, og de nådde opp til
nasjonalt nivå i sine øvelser. Måmoen ble norgesmester i tikamp i 1927, og
Sigurd Dahle, også allsidig som Måmoen, fikk sitt norgesmesterskap i kule. Før NM i 1934 ble det stilt spørsmål ved tyngden på kulene som Sigurd Dahle
benyttet. I et par konkurranser lokalt hjemme i Søndeled oppnådde han
Åmli i
m. I 1927 ble
ti-kamp – for
sforening. Olav Måmoen fra Åmli i
underoffisersuniform. I 1927 ble
han norgesmester i ti-kamp – for
Kristiansand Idrettsforening. 138 «sørlandsmesterskapet» fantastiske resultater. Men i norgesmesterskapet var kulene kontrollveid, og
Sigurd Dahle støtte kula 14,64 meter, nærmere meteren lengre enn nr. 2. «‘Kong Sigurd’ hadde kronet sin lange karriere med et overlegent NM.»50 Olav Måmoen dro fra landet i 1931 og utdannet seg til lege og tannlege
i Tyskland. Han kom tilbake til Norge etter krigen og bosatte seg i Oslo. Sigurd Dahle ble etter idrettskarrieren lærer i videregående skole. Ved
inngangen til krigen var han friidrettslærer på Statens Gymnastikkskole,
og fortsatte med det også etter krigen. Under krigen var han i Sverige,
som instruktør på idrettskurs der. I 1958 kom han hjem til Søndeled for
å overta gården, og gjennom 1960-tallet dro han rundt som instruktør
i fylket. Hver sommer arrangerte han treningsleirer for unge gutter på
gården, en leir som blant annet Finn Bendixen fra Lillesand dro nytte av.51 Kristiansand med sine utdanningsinstitusjoner kan ses på som den
store driveren for mange idrettsutøvere. Den menneskelige faktoren Fra omkring 1970 utviklet byen
seg videre som utdanningssentrum på Agder med opprettelse av Agder
Distriktshøgskole. Idrettsfaglig utdanning fikk Kristiansand Lærer
høgskole på 1970-tallet, og denne ble videre utbygget etter fusjonen
mellom seks utdanningsinstitusjoner til Høgskolen i Agder i 1994 og til
Universitetet i Agder i 2007. Kristiansandsidretten har tydelig profitert på
dette, men det har også andre deler av Agder.52 50
Fredriksen 1998: 68
51
Justvik 2018: 194–195
52
Fjeld 2017: 548ff Allsidigheten og de små, aktive bygdemiljøene Allsidighet kan karakteriseres som en tradisjon på Agder. Stockingers
idrettsbegrep var ikke knyttet til spesialisering, men allsidighet. Under para-
plyen Arendals Turnforening ble det drevet en mengde idrettsaktiviteter. Fra
slutten av 1800-tallet, da Centralforeningen for Idrett bidro med kongepoka-
ler i regionale konkurranser, var det i den gamle klassiske kombinertidretten
– hopp og langrenn. Mellom 1893, da Andreas Midtbø fra Holt fikk den første
kongepokalen i kombinert på Agder, og fram til 1926, da den siste konge-
pokalen i kombinert ble utdelt, tok austegdene åtte slike. Vestegder tok bare
halvparten. Som sørlandsmesterskap gikk dette i Aust-Agders favør. Allsidighet kan karakteriseres som en tradisjon på Agder. Stockingers
idrettsbegrep var ikke knyttet til spesialisering, men allsidighet. Under para-
plyen Arendals Turnforening ble det drevet en mengde idrettsaktiviteter. Fra
slutten av 1800-tallet, da Centralforeningen for Idrett bidro med kongepoka-
ler i regionale konkurranser, var det i den gamle klassiske kombinertidretten – hopp og langrenn. Mellom 1893, da Andreas Midtbø fra Holt fikk den første
kongepokalen i kombinert på Agder, og fram til 1926, da den siste konge-
pokalen i kombinert ble utdelt, tok austegdene åtte slike. Vestegder tok bare
halvparten. Som sørlandsmesterskap gikk dette i Aust-Agders favør. – hopp og langrenn. Mellom 1893, da Andreas Midtbø fra Holt fikk den første
kongepokalen i kombinert på Agder, og fram til 1926, da den siste konge-
pokalen i kombinert ble utdelt, tok austegdene åtte slike. Vestegder tok bare
halvparten. Som sørlandsmesterskap gikk dette i Aust-Agders favør. 139 53
Justvik 2018: 59–60, 96–97 kapittel 6 Et annet trekk ved kongepokalene i kombinert er at alle
de fire i Vest-Agder gikk til Kristiansand og Oddersjaa. Kristiansand-dominansen var tydelig i vest. Slik var det
ikke i Aust-Agder. To kongepokaler gikk til Holt, og tre til
Songe Skiklubb. Det er et tydelig trekk at Arendalsområ-
det ikke hadde den sentrale posisjonen som Kristiansand
hadde. Songe, mellom Tvedestrand og Risør, ble fra 1912
et sentralt sted for skiidrett. Østlendingen Albert Wüller
etablerte Songe Træsliberi dette året, og ble den store driv-
kraften for å utvikle en hoppbakke og danne en skiklubb. I 1923 ble Agders første norgesmesterskap – landsrenn som
det het den gang – i hopp arrangert i Songebakken, og
langrenn i området fra Søndeled og innover mot Vegårshei. Skimiljøet på Songe var godt, og det trakk til seg dyktige
skiløpere, blant annet Georg Østerholt fra Gjerstad, som
fikk kongepokalen i 1918. Før han i 1920 flyttet til hoved-
staden på grunn av jobben som takstmann i Oslo-marka,
hadde han tatt underoffisersutdannelse. Han hadde også
utdannet seg til skogtekniker på Statens skogskole på
Kongsberg. I Oslo ble han medlem av Lyn, og deltok i flere
på nasjonalt og internasjonalt nivå med gode resultater. Før Reidar
reassen og Ole Tom Nord var Georg Østerholt den som nådde lengst
n skiidrett på Agder.53
e
r
tiden. ubb,
eren
or
or Albert Wüller var den store
idrettslederen i Aust-Agder
gjennom hele mellomkrigstiden. Hans base var Songe Skiklubb,
men han ble den første lederen
i Aust-Agder Distriktslag for
Idrett fra 1919, samt leder for
skikretsen i Aust-Agder. Vegårshei er et annet område som kan trekkes fram med hensyn til
skiidrett etter krigen. Et sentralt moment var snøsikkerheten i dette
området. For Ole Tom Nord var det nokså avgjørende at han hadde fri-
billett på NSB når han skulle til Vegårshei på samlinger. Den sentrale
personen på Vegårshei var Knut Adolf Moland, som betydde mye for
Ole Tom Nords utvikling som hopper. Han ble lagt merke til nasjonalt. Molands sønn, Asbjørn, var et produkt av miljøet og vant «ungguttenes
norgesmesterskap», Kronprinsens pokal, to år på rad, i 1952 og 1953. Han
var jevngammel med Toralf Engan. Engan hadde aldri en sjanse mot
Asbjørn Moland i 1953, og ble rådet til å peile seg inn på andreplassen i 140 «sørlandsmesterskapet» Georg Østerholt kom fra Gjerstad der bildet er tatt, nærmere bestemt fra Storheia i
Egddalen. 54
Justvik 2018: 187 kapittel 6 Etter numrene å dømme deltok nærmere 40 hoppere, bare fem fra bygda. Sørlandsbanen var viktig for deltakelsen i både langrenn og hopp i Gjerstad. Georg Østerholt kom fra Gjerstad der bildet er tatt, nærmere bestemt fra Storheia i
Egddalen. Etter numrene å dømme deltok nærmere 40 hoppere, bare fem fra bygda. Sørlandsbanen var viktig for deltakelsen i både langrenn og hopp i Gjerstad. rennet: «... det nytter ikke for deg å tenke på førsteplassen. Du må hoppe
om andreplassen.» Seinere i karrieren flyttet Asbjørn Moland fra Agder,
og satset så hardt på utdannelse og jobb at det ble vanskelig å kombinere
med innsats i hoppbakken. Som Georg Østerholt deltok han i nasjonale
og internasjonale konkurranser med hederlige resultater. En niendeplass
i den tysk-østerrikske hoppuka er ikke å forakte.54 Ovenfor har det vært mer enn antydet at de to fylkene er noe for
skjellige når det gjelder spenningene mellom de kristne og de frilynte
miljøene. Songe og Vegårshei hadde store, toneangivende og veletablerte
frikirkelige miljøer, henholdsvis Den evangelisk lutherske Frikirke og
Guds menighet på Vegårshei. Det har ikke vært avdekket sterke spennin-
ger mellom idretten og idrettsgrupperingene på de to stedene, men så var
det nasjonalidretten ski som dominerte i de to bygdene. Dette nasjonale
perspektivet skal ikke undervurderes. Flere av hopperne og langrenns-
løperne fra området deltok flere år i nasjonalanlegget Holmenkollen. En informant, riktignok fra en av nabobygdene i Aust-Agder, mente at 141 kapittel 6 deltakelse i Holmenkollen fikk mye av kritikken fra konservativt kristent
hold til å forstumme. Landsrennet i 1923, det første på Agder, ble arran-
gert i området mellom Songe og Vegårshei og har også betydd en del i
dette nasjonale perspektiv. Ikke minst ved at kong Håkon bivånet hopp-
rennet i Songebakken, og kronprins Olav deltok i junior-
klassen med hederlig resultat. Forholdene på renndagen var
dårlige – etter flere dager med mildvær frøs bakken til, og
«hoppbakken ble mest som blåis». Flere var bekymret for
kronprinsens deltagelse. Da grep kongen inn: «Kan andre
norske gutter hoppe i bakken, så kan min sønn gjøre det.»
Det nasjonale sinnelag blir ikke mindre når slikt kommer
ut. Det hører riktignok med til historien at Wüller selv
måtte beordre en av de lokale hopperne, Ingvald Songe, til
å hoppe først.55 Johanne Greibrokk, allsidig
idrettsutøver på nasjonalt nivå
like etter andre verdenskrig, fra
en av de indre bygdene – Grendi. kapittel 6 Som vi har sett, ble Arendal aldri så sentral innenfor
idretten i Aust-Agder som Kristiansand ble det i Vest-
Agder. Relativt tidlig oppstod små, kraftfulle miljøer rundt
om i Aust-Agder. Noen av disse, som Vegårshei og Songe,
fikk en relativt kort blomstringsperiode for så å dø hen,
mens andre ble varige, og har holdt stand helt fram til i dag. Johanne Greibrokk, allsidig
idrettsutøver på nasjonalt nivå
like etter andre verdenskrig, fra
en av de indre bygdene – Grendi. 55
Justvik 2018: 97 Konklusjon Har påstandene i artikkelen om den organiserte idrettsbevegelsen regio
nalt fra 1839 til 1970 blitt bekreftet eller avkreftet? Er det et kjennetegn at
miljøene var små og tette, og at det fantes flere idrettsutøvere med all-
sidighet som ideal? Var fylkene ulike på noe vis, var miljøene i øst mer
vitale enn i vest? Finner vi også en ulikhet mellom de to sentrale byene
ved at Kristiansand etter hvert ble langt viktigere for idretten i Vest-
Agder enn Arendal ble for Aust-Agder? Og var det slik at den pietistiske
vekkelsesbevegelsen hemmet utviklingen av idretten i landsdelen, men at
Aust-Agder ble minst hemmet? 55
Justvik 2018: 97 142 «sørlandsmesterskapet» Demografien i de to fylkene i hundreårsperioden fram til 1970 er ulik. Utgangspunktet i 1870 var likt – det var omtrent like mange austegder som
vestegder, omkring 75 000. Men gjennom hundreåret stod antall austeg-
der på stedet hvil, mens innbyggertallet i Vest-Agder økte til omkring
120 000. Utflyttingen fra Aust-Agder var større enn fra Vest-Agder, og
en av konsekvensene var at bygdemiljøene i begge fylkene var små, men
at Aust-Agders miljøer relativt sett var de minste. Utflyttingen fra Agder
førte egdene ut av landet, og mange flyttet også til andre steder i lan-
det for utdannelse og jobb. Allsidige Helge Løvland dro til Kristiania for
militær topputdanning og ble værende der livet ut, men spilte en innfly-
telsesrik rolle innen idretten i Aust-Agder. En rekke andre kunne nevnes,
særlig fra Aust-Agder. Likevel førte ikke dette til at idrettsmiljøene syk-
net hen og ble borte. Flere miljøer har vært nevnt, som Songe, Vegårshei
og nettverkskommunene innen skiidrett på 1950- og 60-tallet Herefoss,
Mykland, Åmli og Vegusdal i Aust-Agder. Åmli med Dristug – den eldste bygdeidrettsklubben på Agder – har
nok den sterkeste og mest imponerende historien av disse små, vitale
idrettsmiljøene. Dristug ble dannet i 1895 som skiklubb, og siden kom
flere idretter, ikke minst friidrett, som under elendige baneforhold fram-
brakte den allsidige Olav Måmoen. Dristug ble hardt rammet av skismaet
i idretten på 1930-tallet, en sak som nesten gikk til topps i rettssystemet. Selv om arbeideridretten tapte saken, har den dominert resten av his-
torien i bygda med volleyballsatsing helt til idag. Det startet som kvinne
idrett, med allsidige Aslaug Solheim på laget. Allsidighetsideal innen idretten er gjennomgående. Konklusjon Idretten som
Stockinger innførte var ikke bare legemsøvelser i snever forstand, men
innbefattet langt mer, slik som naturglede, sosialt brorskap, likhet,
nasjonal enhet og offervilje. Dette harmonerte godt med Centralforenin-
gens allsidighetsprogram om å danne og utvikle fedrelandsforsvarere. Idrett skulle inn i skolen, og skiidrett skulle vektlegges. Responsen på
Agder blant de frilynte ungdomslagene var fulltonig. Begge fylkes
organisasjonene var innmeldt i Centralforeningen fram til 1919, og de
satset på idrett. Fra 1839 til 1877 foregikk lærerutdannelsen i Holt. Den fysiske fostrin-
gen av framtidige lærere kom tidlig i gang her, tidligere enn ved andre 143 kapittel 6 lærerseminarer. I 1877 ble utdanningen flyttet til stiftsstaden, som fra før
hadde utdanningsinstitusjonen Underoffiserskolen. Egder, og i flere til-
feller unge menn fra andre landsdeler, flyttet til Kristiansand og fikk sin
utdannelse i byen, samtidig som deres idrettslige ferdigheter ble bedre. Flere av disse dro tilbake til sine hjemsteder, og ble sentrale i oppbyggin-
gen av idrettsmiljøer der. Andre fremragende idrettsutøvere dro videre
ut for utdannelse og jobb. Før de dro videre, bidro de til et løft for kris-
tiansandsidretten. Austegdene Olav Måmoen og Sigurd Dahle var nær-
mest et kretslag alene – for Vest-Agder. Helt fram til 1970 var Kristiansands-idretten dominerende i Vest-
Agder. Øyslebø kan trekkes fram som et miljø som etter andre verdens-
krig kunne gjøre stiftsstaden rangen stridig med blant annet Ole Tom
Nord, det ektefødte barn av Sørlandsbanen. Men dette var mer unntaket
som bekreftet regelen. Kristiansand var dominerende i Vest-Agder, mens
de små, vitale idrettsmiljøene dominerte i Aust-Agder. Etter 1900 klarte
ikke Arendal å dominere innen idretten. Stockinger døde i 1903. Aren-
dal hadde ingen sentrale institusjoner som kunne trekke folk til byen. Kristiansand hadde endatil fått seminaret i 1877. En kontrafaktisk hypo-
tese skal nevnes, men ikke besvares: Hva hvis Arendals-området hadde
beholdt seminaret? Kunne det ha utgjort en forskjell? Hundreåret som er gjennomgått for idrettsutfoldelsen på Agder er også
blitt karakterisert som det gyldne hundreår for den lekmannsbaserte
vekkelseskristendommen. Fikk denne kristendomsformen innflytelse på
idrettsutviklingen? Det har vært vist til forskning på dette området som
forteller at denne kristendomsformen fikk innflytelse på idrettsutviklin-
gen på Agder, en vesentlig del av det såkalte «bibelbeltet». Men de små,
tette idrettsmiljøene i Aust-Agder har vist at det, til tross for spennings-
forhold til vekkelsesfolket, var mulig å drive idrett på høyt og intensivt
nivå. Informanter Informanter for volleyball i Åmli 1990–2018: Tore Flottorp, Inge Ljøner Ringdahl,
Jetmund Berntsen og Jostein Olimstad. Kilder Aviser, tidsskrift
Agderposten, 28.2.1967
Fædrelandsvennen, 1.3.1967
Norsk idrætsblad, nr. 45, fredag 11.9.1881
Norsk Idrætsblad og Sport, 1920, Julenummeret
Norsk Skytter-Tidende, 15. mars 1864
Norske Turnnotitser, 1889–1893 Årbøker Centralforeningens Årsberetning 1864
Centralforeningens Årsberetning 1865
Centralforeningens Årsberetning 1868
Centralforeningens Årbok 1904
Centralforeningens Årbok 1906 Konklusjon Funnene som er presentert i dette kapittelet kan tyde på at dette var
enklere å få til i disse små, tette miljøene i Aust-Agder enn i Vest-Agder. 144 «sørlandsmesterskapet» Litteratur Braadland, J. F. (2009, 13. februar). Andreas Faye. I Store norske leksikon. https://nbl.snl.no/Andreas_Faye Braadland, J. F. (2009, 13. februar). Andreas Faye. I Store norske leksikon. https://nbl.snl.no/Andreas_Faye Bø, I. W. (1956). Sports- og idrettsliv i Aust-Agder. I H. M. Fiskaa & H. Falck
Myckland (Red.), Norges bebyggelse. Sørlige seksjon. Fylkesbindet for Aust-Agder,
Vest-Agder og Rogaland fylker, s. 208–224. Norsk Faglitteratur. Byklum, O. J. (1958). Kristiansands Turnforening 1858 – 17. oktober – 1958. Edgar
Høgfeldt. Dannevig, B. (1979). Froland: Bd 1. Bygd og samfunn. Froland kommune. Dokkedal, G. (2011). Skøytesporten i Aust-Agder 1870. Arendal Skøiteklub. Fjeld, J. B. (2017). Utdanning av instruktører og ledere til idretten i Vest-Agder
gjennom 200 år. I N. M. Justvik (Red.), Idrett i Sør. Vest-Agder Idrettskrets 100 år
1917–2017, s. 539–556. Portal forlag. Fjeld, J. B. (2017). Utdanning av instruktører og ledere til idretten i Vest-Agder
gjennom 200 år. I N. M. Justvik (Red.), Idrett i Sør. Vest-Agder Idrettskrets 100 år
1917–2017, s. 539–556. Portal forlag. 145 kapittel 6 H. Falck Myckland (Red.), Norges bebyggelse. Sørlige seksjon. Fylkesbindet for
Aust-Agder, Vest-Agder og Rogaland fylker, s. 501–508. Norsk Faglitteratur. Justvik, N. M. (2012). Idrett og kristendom på Sørlandet 1945–2000. Portal
Akademisk. Justvik, N. M. (2017). Idrett i Sør. Vest-Agder Idrettskrets 100 år 1917–2017. Portal
forlag. Justvik, N. M. (2018). Fra hav til hei. En fortelling om idrett i Aust-Agder. Cappelen
Damm Akademisk. Lande, G. (1968). Vest-Agder Ungdomslag 75 år. 1893–1968. Kristiansand. Langmyr, H. (2014). Songe skiklubb 1914–2016. Utgitt av Stian Grasåsen og Harald
Langmyr. Leewy, K. (1980). Kristiansands bebyggelse og befolkning i eldre tider: Bd. 2. Østre
d
h
d
b
k
f
d Leewy, K. (1980). Kristiansands bebyggelse og befolkning i eldre tider: Bd. 2. Østre
Strandgate 1. Christianssands Sparebank Historiefond. Line, J. E. (1932). Arendals turnforening 75 ÅR. 17de mai 1857 – 17de mai 1932. Minneskrift (for de siste 25 år) 17de mai 1907 – 17de mai 1932. O. Fredr. Arnesen
bok- og akcidenstrykkeri. Løvland, H. (1971). Det endte godt i Antwerpen. I A. Møst (Red.), Høydepunkter i
norsk fri-idrett 1896–1971, s. 20–24. Norges Friidrettsforbund. Norges idrettshøgskole. (u.å.). I Wikipedia. https://no.wikipedia.org/wiki/Norges_
idrettsh%C3%B8gskole Olstad, F. (1987). Norsk idretts historie. Forsvar, sport, klassekamp 1861–1939. Olstad, F. (1987). Norsk idretts historie. Forsvar, sport, klassekamp 1861–1939. I F. Olstad & S. Tønnesson (Red.), Norsk idretts historie. H. Aschehoug & Co. (W Nygaard) Aschehoug I F. Olstad & S. Tønnesson (Red.), Norsk idretts historie. H. Aschehoug & Co. (W. Bildene i dette kapitlet er hentet fra åpne, offentlige kilder. Mulige nålevende
rettighetshavere er ukjent. Litteratur Nygaard) Aschehoug.l I F. Olstad & S. Tønnesson (Red.), Norsk idretts historie. H. Aschehoug & Co. (W N
d) A h h Olympiastadion. (2016, 13. august). De flyvende marmorstatuer: 110 år siden Norges
første OL-gull – Jan Holm. https://olympiastadion.no/2016/08/13/de-flyvende-
marmorstatuer-110-ar-siden-norges-forste-ol-gull-jan-holm/ Olympiastadion. (2016, 13. august). De flyvende marmorstatuer: 110 år siden Norges
første OL-gull – Jan Holm. https://olympiastadion.no/2016/08/13/de-flyvende-
marmorstatuer-110-ar-siden-norges-forste-ol-gull-jan-holm/ Raustøl, B. (2008, 9. oktober). Byens første olympiske mester. Da Norge tok gull i
troppsgymnastikk i Athen-OL i 1906, var slagtersvennen Johan Leopold Stumpf
fra Kristiansand med på laget. Fædrelandsvennen. Repstad, P. (2002). Mellom inderlighet og spissborgerskap. En samfunnsforsker ser
på sørlandspietismen. I H. Inntjore (Red.), Agderkirken. Artikler fra høgskolens
sommerseminar i historie, Lillesand 2000, s. 95–109. Høgskolen i Agder. Repstad, P. (2002). Mellom inderlighet og spissborgerskap. En samfunnsforsker ser
på sørlandspietismen. I H. Inntjore (Red.), Agderkirken. Artikler fra høgskolens
sommerseminar i historie, Lillesand 2000, s. 95–109. Høgskolen i Agder. Seland, B. & Aagedal, O. (2008). Vekkelsesvind. Den norske vekkingskristendommen. Det Norske Samlaget. Seland, B. & Aagedal, O. (2008). Vekkelsesvind. Den norske vekkingskristendommen. Det Norske Samlaget. 146 «sørlandsmesterskapet» Slettan, B. (1992). «O at jeg kunde min Jesum prise…» Folkelig religiøsitet og
vekkelsesliv på Agder på 1800-tallet. Universitetsforlaget. Songedal, S. (2002). Ole Lauve. Vegårshei IL’s første formann. Vegårshei IL. https://docplayer.me/22200760-Ole-lauve-vegarshei-il-s-forste-formann.html Steen, S. (1948). Kristiansands Historie. I fredens århundre 1814–1914. Grøndahl &
Søn. Stockinger, F. (1903). Omkring Joseph Stockinger. Stamfader til den norske Slekt Stockinger, F. (1903). Omkring Joseph Stockinger. Stamfader til den norske Slekt
Stockinger. 1828–1865. Hedre din Fader og din Moder at det kan gaa dig vel. Stockinger, F. (1907). Mindeskrift ved Arendals Turnforenings 50-aars Jubilæum. Arendals Bogtrykkeri. Stubhaug, A. (2014). Jacob Aall i sin tid. Aschehoug.h Thyness, P. (2009, 13. februar). Nils Hertzberg. I Store norske leksikon. https://nbl.snl.no/Nils_Hertzberg Try, H. (1979). To kulturer – en stat 1851–1884. I K. Mykland (Red.) Norges historie. J.W. Cappelens Forlag. Vågsdalen, K. A. (2013). Idrettslaget Gry’s historie og andre aktiviteter i Vegusdal
1946–2012. Birkeland Trykkeri. Wivestad, R. (1989). Kroppsøvingsfaget i utvikling. I R. Harbo, B. J. Monstad &
H. K. Solm (Red.), Ansvar, kunnskap og vekst. Kristiansand Lærerhøgskole 1839–
1989, s. 122–129. Kristiansand Lærerhøgskole. Wivestad, R. (1989). Kroppsøvingsfaget i utvikling. I R. Harbo, B. J. Monstad &
H. K. Solm (Red.), Ansvar, kunnskap og vekst. Kristiansand Lærerhøgskole 1839– Wivestad, R. (1989). Kroppsøvingsfaget i utvikling. I R. Harbo, B. J. Monstad &
H. K. Solm (Red.), Ansvar, kunnskap og vekst. Kristiansand Lærerhøgskole 1839–
1989, s. 122–129. Sitering av dette kapitlet: Magnussen, M.-L. (2020). Kjønnede hverdagsliv og likestillingsutfordringer på
Agder: Regionale særtrekk og variasjoner i landsdelen. I Johnsen, B.E. og Vadum, K. (red.), Grenseløst
Agder. Det som skilte og det som bandt (s. 148–171). Oslo: Cappelen Damm Akademisk. https://doi.
org/10.23865/noasp.111
Lisens: CC BY-NC-ND. Litteratur Kristiansand Lærerhøgskole. Wold, A. (1959). Trondhjems Turnforening 1858 – 14. Februar – 1958. Wold, A. (1959). Trondhjems Turnforening 1858 – 14. Februar – 1958. En hundreårskavalkade. Trondheim. Østreim, J. (2016). Froland IL 1916–2016. Idrettsglede gjennom 100 år. Froland
Idrettslag. Østreim, J. (2016). Froland IL 1916–2016. Idrettsglede gjennom 100 år. Froland
Idrettslag. Aanby, S. (1995). Dristug 1895–1995. IL Dristug. Aanby, S. (1995). Dristug 1895–1995. IL Dristug. Aanby, S. (1997). Nettball og volleyball i Aust-Agder. Aust-Agder Volleyballkrets 1947–
1997. Aust-Agder Volleyballkrets. Aanby, S. (1997). Nettball og volleyball i Aust-Agder. Aust-Agder Volleyballkrets 1947–
1997. Aust-Agder Volleyballkrets. Bildene i dette kapitlet er hentet fra åpne, offentlige kilder. Mulige nålevende
ettighetshavere er ukjent. Bildene i dette kapitlet er hentet fra åpne, offentlige kilder. Mulige nålevende
rettighetshavere er ukjent. Bildene i dette kapitlet er hentet fra åpne, offentlige kilder. Mulige nålevende
rettighetshavere er ukjent. 147 147 kapittel 7 Regionale særtrekk og
variasjoner i landsdelen May-Linda Magnussen Helt siden Statistisk sentralbyrå (heretter SSB) lanserte sin likestillings
indeks i 1999, har Agder kommet dårlig ut på statistikk som har som for-
mål å måle grad av kjønnslikestilling på ulike områder, sammenlignet
med andre deler av Norge. Over flere år ble landsdelen faktisk rangert
som den aller minst likestilte delen av Norge. I dag utvikler ikke SSB len-
ger et samlemål på likestilling i kommuner og fylker. Det som nå i stedet
kalles indikatorer for kjønnslikestilling i kommunene, levner imidlertid
liten tvil om at Agder fremdeles har relativt store likestillingsutfordrin-
ger på flere områder. I dette kapitlet presenterer jeg statistikk fra SSB som sier noe om like-
stillingsutfordringer på Agder i dag, og bruker denne til å drøfte hvordan
landsdelen ser ut til å skille seg fra andre deler av Norge når det gjelder
slike utfordringer. Denne statistikken bruker jeg også til å vise og drøfte
likestillingsvariasjoner mellom ulike deler av Agder. Jeg vil imidlertid
også prøve å gå bak det bildet som statistikken fra SSB danner. Det betyr
at jeg vil bruke egen og andres forskning til å reflektere rundt mulige
årsaker til at folks hverdagsliv på Agder ser ut til å være mer kjønnede
enn hva som gjelder for landet ellers, men også årsaker til at det ser ut til 148 kjønnede hverdagsliv og likestillingsutfordringer på agder å være variasjoner innad i landsdelen når det gjelder dette. Det innebærer
også å bruke forskning som kan synliggjøre måter å tenke rundt og orga-
nisere menneskelig virksomhet på som har lange historiske røtter, men
som fremdeles den dag i dag ser ut til å forme folks hverdagsliv på Agder. For å kunne forstå slike sosiale prosesser, trenger vi imidlertid forskning
som går bak det øyeblikksbildet samfunnsforskning ofte bidrar til å gi. Bjørg Seland bruker historisk forskning som kan bidra til slik forståelse i
neste kapittel av denne boka. 1
Dette gir ikke mening for indikator 1 og 7. Her er andelen imidlertid delt på 100 for kunne ligge
på en skala fra 0–1, som de andre indikatorene. Statistikk som viser at
Agder er en lite likestilt landsdel SSBs likestillingsstatistikk dekker i dag et stort spekter av dimensjoner,
og skal si noe om kjønnslikestilling i både familierelasjoner, utdannings-
system, arbeidsliv og det politiske liv. De fleste indikatorene sier imid-
lertid noe om likestillingssituasjonen i arbeidslivet. Tabellen under viser
landets og fylkenes skårer på alle de ulike indikatorene, basert på tall
fra 2018. SSB skriver at «for hver indikator får kommunene en skår som
kan variere fra 0, som indikerer maksimal forskjell/ulikhet mellom kjøn-
nene, til 1 som indikerer full likestilling. Utgangspunktet er at der det
er liten forskjell mellom kvinner og menn, tolkes dette som likestilling. Jo større forskjell, jo mindre likestilt» (SSB, 2019).1 Det er altså kjønns-
balanse som måles. Det vil si at fylker som for eksempel har relativt få
kvinner i arbeidsstyrken kan få en bra skår på indikator 4, «forholdet
mellom kvinner og menn i arbeidsstyrken», dersom også relativt få menn
er i arbeidsstyrken – noe som gjelder for Agders del. 149 kapittel 7 kapittel 7 Tabell 1. Skår per likestillingsindikator 2018, for landet og fylker Tabell 1. Skår per likestillingsindikator 2018, for landet og fylker Indikator
1
2
3
4
5
6
7
8
9
10
11
12
Landet
0,92
0,78
0,79
0,94
0,69
0,46
0,71
0,60
0,60
0,74
0,73
0,67
Østfold
0,9
0,76
0,76
0,91
0,71
0,43
0,66
0,58
0,58
0,71
0,68
0,67
Akershus
0,93
0,89
0,85
0,94
0,67
0,47
0,74
0,65
0,62
0,78
0,72
0,72
Oslo
0,89
0,78
0,91
0,96
0,7
0,65
0,69
0,74
0,71
0,86
0,81
0,76
Hedmark
0,92
0,81
0,7
0,92
0,74
0,45
0,68
0,56
0,61
0,68
0,74
0,65
Oppland
0,93
0,8
0,69
0,93
0,73
0,43
0,7
0,55
0,57
0,69
0,72
0,64
Buskerud
0,91
0,82
0,8
0,93
0,69
0,42
0,7
0,59
0,55
0,74
0,69
0,66
Vestfold
0,91
0,79
0,8
0,92
0,68
0,43
0,68
0,59
0,56
0,72
0,64
0,68
Telemark
0,92
0,7
0,73
0,93
0,7
0,4
0,66
0,55
0,53
0,68
0,7
0,66
Aust-Agder
0,92
0,71
0,76
0,94
0,69
0,41
0,67
0,57
0,58
0,69
0,69
0,65
Vest-Agder
0,9
0,72
0,76
0,93
0,67
0,41
0,69
0,56
0,55
0,7
0,66
0,65
Rogaland
0,9
0,74
0,76
0,94
0,64
0,39
0,72
0,57
0,5
0,71
0,67
0,65
Hordaland
0,93
0,75
0,78
0,95
0,68
0,43
0,72
0,59
0,6
0,74
0,71
0,66
Sogn og
Fjordane
0,93
0,78
0,65
0,96
0,72
0,44
0,76
0,51
0,51
0,63
0,78
0,63
Møre og
Romsdal
0,93
0,76
0,7
0,94
0,67
0,38
0,73
0,52
0,51
0,66
0,7
0,65
Trøndelag
0,94
.. 0,78
0,94
0,72
0,45
0,74
0,58
0,61
0,7
0,73
0,66
Nordland
0,93
0,79
0,7
0,95
0,74
0,46
0,66
0,55
0,61
0,67
0,79
0,64
Troms
0,95
0,74
0,71
0,95
0,76
0,54
0,71
0,58
0,68
0,67
0,78
0,67
Finnmark
0,91
0,79
0,58
0,97
0,8
0,59
0,64
0,58
0,64
0,66
0,76
0,63 Indikatorer 1: Andel barn 1–5 år i barnehage
2: Kjønnsfordeling blant kommunestyrerepresentanter
3: Forholdet mellom kvinner og menn med høyere utdanning
4: Forholdet mellom kvinner og menn i arbeidsstyrken
5: Forholdet mellom menns og kvinners bruttoinntekt
6: Forholdet mellom menns og kvinners deltidsarbeid
7: Andel fedre som tar hele fedrekvoten eller mer av foreldrepengeperioden
8: Grad av kjønnsbalansert næringsstruktur
9: Kjønnsbalanse i offentlig sektor
10: Kjønnsbalanse i privat sektor
11: Kjønnsfordeling blant ledere
12: Grad av kjønnsbalanserte utdanningsprogram i videregående skole
Kilde: SSB, 2019 150 kjønnede hverdagsliv og likestillingsutfordringer på agder Agder hadde tidligere relativt lav barnehagedekning, men har nå en
barnehagedekning omtrent på landsgjennomsnittet. kapittel 7 Samtidig ser vi at
barnehagedekningen i Agder (som var to fylker i 2018) likevel ligger under
det som gjelder for mange andre av landets fylker, og vi har grunn til å tro
at Oslo trekker snittet ned. Når det gjelder kvinneandel i politikken ligger
Agder klart under landsgjennomsnittet, og også under alle andre fylker
unntatt Telemark. På kjønnsbalanse i høyere utdanning skårer Agder
noe lavere enn landsgjennomsnittet, men her ser det ut som om Oslo og
Akershus trekker snittet opp, og at Agder dermed ikke skiller seg så mye
fra andre deler av landet. Når det gjelder forholdet mellom menn og kvin-
ner i arbeidsstyrken, ser ikke Agder ut til å skille seg noe særlig ut, hverken
i forhold til landsgjennomsnittet eller andre deler av landet. Det samme
ser ut til å gjelde for forholdet mellom menns og kvinners bruttoinntekt. Flere fylker skårer bedre enn Agder her, men der er også en del som skå-
rer omtrent likt. Når det gjelder forholdet mellom menns og kvinners
deltidsarbeid, derimot, skårer Agder lavere enn landsgjennomsnittet, og
også lavere enn de fleste andre fylkene. Ifølge SSBs likestillingsstatistikk
fra 1999 og fremover er også nettopp kvinners arbeidstid den dimensjo-
nen Agder virkelig har skilt seg fra landet for øvrig på, i den forstand at
denne har vært betydelig kortere enn landsgjennomsnittet. Samtidig er
det verdt å merke seg at Telemark, Rogaland og Møre og Romsdal nå skå-
rer lavere på denne indikatoren enn det Agder gjør. Agder hadde tidligere relativt lav barnehagedekning, men har nå en
barnehagedekning omtrent på landsgjennomsnittet. Samtidig ser vi at
barnehagedekningen i Agder (som var to fylker i 2018) likevel ligger under
det som gjelder for mange andre av landets fylker, og vi har grunn til å tro
at Oslo trekker snittet ned. Når det gjelder kvinneandel i politikken ligger
Agder klart under landsgjennomsnittet, og også under alle andre fylker
unntatt Telemark. På kjønnsbalanse i høyere utdanning skårer Agder
noe lavere enn landsgjennomsnittet, men her ser det ut som om Oslo og
Akershus trekker snittet opp, og at Agder dermed ikke skiller seg så mye
fra andre deler av landet. Når det gjelder forholdet mellom menn og kvin-
ner i arbeidsstyrken, ser ikke Agder ut til å skille seg noe særlig ut, hverken
i forhold til landsgjennomsnittet eller andre deler av landet. Det samme
ser ut til å gjelde for forholdet mellom menns og kvinners bruttoinntekt. kapittel 7 Flere fylker skårer bedre enn Agder her, men der er også en del som skå-
rer omtrent likt. Når det gjelder forholdet mellom menns og kvinners
deltidsarbeid, derimot, skårer Agder lavere enn landsgjennomsnittet, og
også lavere enn de fleste andre fylkene. Ifølge SSBs likestillingsstatistikk
fra 1999 og fremover er også nettopp kvinners arbeidstid den dimensjo-
nen Agder virkelig har skilt seg fra landet for øvrig på, i den forstand at
denne har vært betydelig kortere enn landsgjennomsnittet. Samtidig er
det verdt å merke seg at Telemark, Rogaland og Møre og Romsdal nå skå-
rer lavere på denne indikatoren enn det Agder gjør. Vi ser at andelen fedre på Agder som tar ut hele fedrekvoten eller mer
er lavere enn landsgjennomsnittet, men at flere fylker likevel har lig-
nende – eller lavere – skår. Når det gjelder kjønnsbalansert næringsstruk-
tur skårer Agder også under landsgjennomsnittet. Samtidig får Agder
nokså lik skår som en del andre fylker, og også her ser det ut som om
Oslo drar snittet opp. Det samme ser ut til å være tilfelle når det gjelder
kjønnsbalanse i privat og offentlig sektor. Når det gjelder andelen kvin-
nelige ledere ser vi at Agder skårer lavere enn landsgjennomsnittet, og
også lavere enn de fleste andre fylkene. På kjønnsbalanserte utdannings
programmer i videregående skole, derimot, ser det ikke ut til at Agder
skiller seg nevneverdig fra de fleste andre delene av Norge. 151 kapittel 7 kapittel 7 Selv om det på de enkelte likestillingsindikatorene ofte går an å finne
andre deler av Norge som skårer nokså likt som Agder, viser tabellen over
at agderfylkene samlet sett alltid skårer under landsgjennomsnittet – i
større eller mindre grad. Denne tendensen har også vært tydelig siden SSB
lanserte likestillingsindeksen i 1999. I tabellen under viser jeg noe av den
statistikken som utgjør datagrunnlaget for utarbeidingen av skårene på
likestillingsindikatorene som har med likestilling i arbeidslivet å gjøre. Jeg
velger å rette oppmerksomheten særlig mot slik likestilling fordi Agder
som nevnt, ifølge den likestillingsstatistikken SSB publiserer, særlig skiller
seg fra landet for øvrig ved kvinners korte arbeidstid. Jeg mener også at
likestilling i yrkesaktivitet er en særlig viktig form for likestilling, blant
annet på grunn av de mulighetene slik aktivitet gir for inntekt og med
bestemmelse i viktige samfunnsinstitusjoner, samt betydningen lønnsinn-
tekt har for tilgang til offentlige ytelser som for eksempel sykepenger og
pensjon. Egen inntekt er utvilsomt viktig for den enkeltes handlefrihet i
eget liv. Ikke minst mener jeg at skårene som handler om yrkesaktivitet
og arbeidstid har sammenheng med skårene på mange andre av likestil-
lingsindikatorene (Magnussen, Mydland & Kvåle, 2005). Da SSB laget like-
stillingsindeksen viste det seg at nettopp lav yrkesaktivitet for kvinner var
den indikatoren som alene hadde høyest prediksjonsverdi for lav grad av
likestilling mer generelt (Kjeldstad & Kristiansen, 2001). 152 kjønnede hverdagsliv og likestillingsutfordringer på agder Statistikk som viser likestillingsvariasjoner
innad i Agder-regionen Jeg går nå over til å se nærmere på likestillingsvariasjon innad på Agder,
og tabellen under er den samme som tabell 1, men nå med skårer for kom-
munene på Agder: Tabell 3. Skår per likestillingsindikator 2018, for landet, agderfylker og -kommuner Tabell 3. kjønnede hverdagsliv og likestillingsutfordringer på agder Tabell 2. Statistikk om likestilling i arbeidslivet 2018, for landet og fylker
Andelen
menn
20–66
år i arb. styrken
Andelen
kvinner
20–66 år i
arb.st. Gj.snittlig
brutto-
inntekt,
menn
Gj.snittlig
brutto-
inntekt,
kvinner
Andel
deltidsarb. menn
20–66 år
Andel
deltidsarb. kvinner
20–66 år
Kvinne-
and. blant
ledere
20–66 år
Landet
80,0
75,4
550 300
382 000
18,8
41,3
36,3
Østfold
76,5
69,9
498800
351800
19,2
44,6
34,1
Akershus
82,6
77,7
632400
426100
15,3
32,7
36,1
Oslo
79,6
76,4
624300
436100
19,3
29,5
40,5
Hedmark
78,8
72,8
476900
353300
21,8
48,4
37,0
Oppland
80,8
75,4
486900
357100
21,8
50,3
35,8
Buskerud
80,9
75,5
545100
374800
17,9
42,5
34,5
Vestfold
78,5
72,4
527600
360400
19,4
45,4
31,9
Telemark
77,2
72,0
501700
349200
19,7
49,6
34,8
Aust-Agder
75,4
70,7
502600
347000
21,3
51,8
34,3
Vest-Agder
77,6
72,4
512500
341900
21,5
51,8
32,8
Rogaland
81,2
76,2
600100
383600
16,8
43,7
33,6
Hordaland
80,8
77,0
553700
375100
18,5
42,6
35,5
Sogn og F. 82,9
79,7
509000
364200
20,1
46,0
39,2
Møre og R. 81,4
76,3
531300
358400
18,3
47,8
34,8
Trøndelag
80,5
75,8
514400
369800
20,1
44,8
36,6
Nordland
79,0
75,0
496000
369000
19,5
42,4
39,6
Troms
80,1
76,2
503800
383500
19,9
37,2
38,9
Finnmark
77,7
75,7
471400
378100
21,4
36,2
38,2
Kilde: SSB, 2019 Tabellen over synliggjør blant annet den store kjønnsforskjellen i arbeids-
tid på Agder. Det er verdt å merke seg at tabellen antakeligvis også under-
driver disse forskjellene, siden tidligere statstikkgjennomganger har vist
at deltidsarbeidende kvinner har kortere avtalt arbeidstid enn deltids
arbeidende menn, samt at dette særlig ser ut til å gjelde for Agder (Mag-
nussen & Halvorsen, 2001; Magnussen, Mydland & Kvåle, 2005). Ikke
minst er menns og kvinners deltidsarbeid ofte forskjellig i den forstand at
menn i stor grad jobber deltid på vei inn i og ut av arbeidslivet, altså at de
ofte er for eksempel studenter som har jobb ved siden av studier eller eldre
med helseplager, mens kvinner som jobber deltid i større grad er fordelt
på ulike aldersgrupper (Kitterød & Rønsen, 2012). 153 kapittel 7 Statistikk som viser likestillingsvariasjoner
innad i Agder-regionen Skår per likestillingsindikator 2018, for landet, agderfylker og -kommuner
Indikator
1
2
3
4
5
6
7
8
9
10
11
12
Landet
0,92
0,78
0,79
0,94
0,69
0,46
0,71
0,60
0,60
0,74
0,73
0,67
Aust-Agder
0,92
0,71
0,76
0,94
0,69
0,41
0,67
0,57
0,58
0,69
0,69
0,65
Vest-Agder
0,9
0,72
0,76
0,93
0,67
0,41
0,69
0,56
0,55
0,7
0,66
0,65
Risør
0,89
0,76
0,75
0,95
0,69
0,45
0,66
0,53
0,54
0,63
0,75
0,64
Grimstad
0,93
0,74
0,80
0,95
0,67
0,46
0,69
0,62
0,64
0,71
0,69
0,66
Arendal
0,93
0,82
0,81
0,94
0,71
0,42
0,64
0,59
0,60
0,73
0,68
0,67
Gjerstad
0,86
0,59
0,46
0,95
0,73
0,33
0,80
0,45
0,38
0,63
0,69
0,65
Vegårshei
0,90
0,67
0,57
0,93
0,69
0,31
0,79
0,41
0,41
0,57
0,76
0,58
Tvedestrand
0,94
0,88
0,73
0,93
0,67
0,38
0,63
0,55
0,49
0,66
0,63
0,68
Froland
0,88
0,74
0,65
0,92
0,68
0,37
0,75
0,47
0,51
0,62
0,65
0,60
Lillesand
0,93
0,67
0,76
0,93
0,69
0,41
0,69
0,57
0,58
0,71
0,63
0,66
Birkenes
0,84
0,38
0,70
0,87
0,65
0,31
0,75
0,51
0,53
0,66
0,63
0,63
Åmli
0,83
0,71
0,55
0,90
0,70
0,33
0,63
0,45
0,62
0,59
0,70
0,58
Iveland
0,92
0,71
0,57
0,86
0,64
0,37
0,73
0,45
0,47
0,57
0,97
0,54
Evje og Hornnes
0,89
0,67
0,63
0,95
0,72
0,37
0,63
0,56
0,59
0,70
0,77
0,57
Bygland
0,85
0,80
0,57
0,94
0,76
0,47
0,63
0,44
0,52
0,57
0,88
0,63
Valle
0,98
0,80
0,62
0,93
0,72
0,35
0,60
0,43
0,43
0,50
0,77
0,51
Bykle
0,91
0,62
0,60
0,94
0,62
0,54
0,50
0,56
0,63
0,63
0,64
0,65
Kristiansand
0,91
0,83
0,85
0,95
0,68
0,49
0,68
0,64
0,63
0,75
0,67
0,69
Mandal
0,92
0,80
0,73
0,93
0,65
0,40
0,67
0,56
0,53
0,70
0,66
0,65
Farsund
0,89
0,62
0,66
0,93
0,63
0,32
0,69
0,44
0,44
0,66
0,76
0,60
Flekkefjord
0,91
0,74
0,68
0,97
0,67
0,36
0,72
0,47
0,51
0,60
0,70
0,63
Vennesla
0,90
0,81
0,61
0,90
0,66
0,33
0,69
0,49
0,46
0,65
0,56
0,59
Songdalen
0,84
0,80
0,63
0,90
0,68
0,39
0,65
0,52
0,48
0,65
0,56
0,63
Søgne
0,91
0,59
0,71
0,91
0,63
0,37
0,67
0,53
0,53
0,69
0,60
0,64
Marnardal
0,92
0,86
0,52
0,89
0,64
0,33
0,78
0,40
0,38
0,50
0,55
0,61
Åseral
0,84
0,59
0,51
0,94
0,67
0,34
0,67
0,40
0,44
0,56
0,76
0,47
Audnedal
0,86
0,71
0,46
0,86
0,64
0,33
0,72
0,37
0,40
0,48
0,86
0,55 154 kjønnede hverdagsliv og likestillingsutfordringer på agder kjønnede hverdagsliv og likestillingsutfordringer på agder Lindesnes
0,87
0,57
0,66
0,91
0,66
0,43
0,71
0,46
0,39
0,65
0,66
0,59
Lyngdal
0,92
0,62
0,65
0,92
0,65
0,33
0,69
0,55
0,46
0,72
0,72
0,66
Hægebostad
0,86
0,67
0,52
0,92
0,61
0,34
0,74
0,39
0,36
0,55
0,38
0,47
Kvinesdal
0,88
0,74
0,62
0,94
0,63
0,29
0,71
0,42
0,37
0,54
0,71
0,58
Sirdal
0,86
0,63
0,59
0,97
0,64
0,36
0,71
0,47
0,52
0,58
0,53
0,64 Indikatorer: 1: Andel barn 1–5 år i barnehage
2: Kjønnsfordeling blant kommunestyrerepresentanter
3: Forholdet mellom kvinner og menn med høyere utdanning
4: Forholdet mellom kvinner og menn i arbeidsstyrken
5: Forholdet mellom menns og kvinners bruttoinntekt
6: Forholdet mellom menns og kvinners deltidsarbeid
7: Andel fedre som tar hele fedrekvoten eller mer av foreldrepengeperioden
8: Grad av kjønnsbalansert næringsstruktur
9: Kjønnsbalanse i offentlig sektor
10: Kjønnsbalanse i privat sektor
11: Kjønnsfordeling blant ledere
12: Grad av kjønnsbalanserte utdanningsprogram i videregående skole
Kilde: SSB, 2019 Når det gjelder barnehagedekning, har en del bykommuner i østre deler
av Agder den høyeste, mens en del bygdekommuner øst og vest i fylket
har den laveste dekningen. På kjønnsbalanse i kommunestyrene er det
igjen noen bykommuner øst på Agder, samt Kristiansand og Marnardal,
som skårer høyest, mens en del bygdekommuner i østre og vestre Agder
skårer lavest. Kristiansand, Arendal og Grimstad har mest kjønnsbalanse
når det kommer til menn og kvinner med høyere utdanning, mens en del
bygdekommuner i østre og vestre del i fylket har minst kjønnsbalanse. Flekkefjord og Sirdal har mest kjønnsbalanse når det kommer til menn
og kvinner i arbeidsstyrken, mens en del bygdekommuner i østre og
vestre Agder har minst. En del bygdekommuner i midtre og østre deler
av Agder utmerker seg med relativt små lønnsforskjeller mellom kvinner
og menn, mens Hægebostad og Bykle utmerker seg med høye lønnsfor-
skjeller. Det er i det hele tatt interessant at Bykle, som ifølge den tidligere
presenterte likestillingsindeksen kom ut som en av Norges mest kjønns
likestilte kommuner, nå skårer dårligere enn fylkesgjennomsnittet på
mange av likestillingsindikatorene. Kommunen utmerker seg imidlertid 155 kapittel 7 positivt når det gjelder kjønnsbalanse i offentlig sektor og kjønnsbalanse
i arbeidstid – og det siste vil si at kvinner i Bykle har relativt lang arbeids-
tid, slik det også kom frem i tidligere likestillingsstatistikk fra SSB. kjønnede hverdagsliv og likestillingsutfordringer på agder Når
det gjelder kjønnsbalanse i arbeidstid utmerker også Kristiansand, Grim-
stad og Risør seg med relativt stor balanse, mens en del bygdekommuner
i østre og vestre deler av fylket samt Farsund utmerker seg med særlig
liten kjønnsbalanse i arbeidstid. Farsund har over lang tid vært en kom-
mune som har utmerket seg med særlig lav arbeidstid for kvinner. På andelen fedre som tar ut fedrekvoten eller mer av foreldrepenge
perioden skårer en del bygdekommuner i øst og vest av Agder høyest,
mens en del bygdekommuner i midten og nord i fylket skårer lavest. Her skårer Bykle lavest, med Valle hakk i hæl. Kristiansand, Grimstad
og Arendal skårer høyest på kjønnsbalansert næringsstruktur, mens en
del bygdekommuner øst og vest i fylket skårer lavest. Grimstad, Bykle og
Kristiansand har ifølge indikatorene mest kjønnsbalanse i offentlig sektor,
mens en del bygdekommuner i vestre deler av Agder, samt Gjerstad, skårer
lavest. Når det gjelder privat sektor, er det ifølge likestillingsindikatorene
Kristiansand, Arendal og Lyngdal som kommer best ut med tanke på
kjønnsbalanse, mens Audnedal, Marnardal og Valle kommer dårligst ut. Iveland, Bygland og Audnedal har høyest andel kvinnelige ledere, mens
flere kommuner vest på Agder har de laveste kvinneandelene blant ledere. Indikatorene viser at utdanningsprogrammene i videregående skoler i
Kristiansand, Tvedestrand og Arendal er mest kjønnsbalanserte, mens
utdanningsprogrammene i en del bygdekommuner vest i fylket, samt
Valle, er minst kjønnsbalanserte. Statistikken nevnt over gir ikke mulighet for å konkludere når det gjel-
der eventuelle systematiske likestillingsforskjeller mellom ulike deler av
Agder. Likevel kan det se ut som om der er noen tendenser som også
har blitt nevnt i andre gjennomganger (Magnussen, 2012; Magnussen &
Halvorsen, 2001; Magnussen, Mydland & Kvåle, 2005; Senter for likestil-
ling, 2016). Det kan se ut som om Kristiansand og en del bykommuner
øst for Kristiansand ofte skårer særlig høyt på likestillingsindikatorene,
mens en del bygdekommuner øst og vest i fylket – og kanskje særlig en
del bygdekommuner i den vestlige delen av fylket – ofte skårer særlig lavt 156 kjønnede hverdagsliv og likestillingsutfordringer på agder på likestilling. Det kan se ut som om spesielt en del av agderbyenes pend-
lingsomland skårer særlig lavt på likestilling, mens kommunene som er
lenger fra kyststripa skårer noe mer varierende. kjønnede hverdagsliv og likestillingsutfordringer på agder Når det gjelder kjønnsforskjeller i menns og kvinners arbeidstid,
som jeg retter aller mest oppmerksomhet mot i dette kapitlet, har jeg i
neste tabell rangert agderkommunene etter hvordan de skårer på like-
stillingsindikatoren som sier noe om forholdet mellom menns og kvin-
ners arbeidstid. Kommunene som har størst forskjell i arbeidstid mellom
kvinner og menn, er rangert høyest. I tabellen har jeg også inkludert pro-
sentandelen kvinner som jobbet deltid i 2018: Tabell 4. Skår for likestillingsindikator nr. 6 og prosentandel kvinner som jobber deltid
2018, for landet, agderfylker og -kommuner. Rangert etter lavest skår på likestillings
indikator 6. Tabell 4. Skår for likestillingsindikator nr. 6 og prosentandel kvinner som jobber deltid
2018, for landet, agderfylker og -kommuner. Rangert etter lavest skår på likestillings
indikator 6. Indikator 6:
Forholdet
mellom menns
og kvinners
deltidsarbeid
Prosentandel
kvinner 22–66
år som jobber
deltid
Indikator 6:
Forholdet
mellom menns
og kvinners
deltidsarbeid
Prosentandel
kvinner 22–66
år som jobber
deltid
Landet
0,46
41,3
7. Sirdal
0,36
54,3
Aust-Agder
0,41
51,8
7. Flekkefjord
0,36
59,5
Vest-Agder
0,41
51,8
8. Søgne
0,37
51,3
1. Kvinesdal
0,29
63,7
8. Iveland
0,37
62,9
2. Birkenes
0,31
60,3
8. Evje og H. 0,37
58,6
2. Vegårshei
0,31
61,2
8. Froland
0,37
57,7
3. Farsund
0,32
56,7
9. Tvedestrand
0,38
57,9
4. Åmli
0,33
60,1
10. Songdalen
0,39
53,2
4. Vennesla
0,33
58,7
11. Mandal
0,40
53,4
4. Lyngdal
0,33
57,9
12. Lillesand
0,41
48,6
4. Audnedal
0,33
73,1
13. Arendal
0,42
48,0
4. Marnardal
0,33
63,8
14. Lindesnes
0,43
62,8
4. Åmli
0,33
60,1
15. Risør
0,45
57,9
4. Gjerstad
0,33
59,2
16. Grimstad
0,46
50,5
5. Hægebostad
0,34
71,8
17. Bygland
0,47
57,8
5. Åseral
0,34
77,0
18. Kristiansand
0,49
46,3
6. Valle
0,35
54,0
19. Bykle
0,54
43,4
Kild
SSB 157 kapittel 7 Tabellen viser at mange bygdekommuner som nevnt har den største
forskjellen i arbeidstid mellom menn og kvinner. Vi ser også at noen
av bykommunene vest for Mandal har stor kjønnsubalanse i arbeidstid,
mens bykommunene fra Mandal og østover, samt setesdalskommunene
Bygland og Bykle, kommer bedre ut. Tabellen viser i tillegg at Åseral har
aller mest deltidsarbeid blant kvinner, med Audnedal og Hægebostad på
andre- og tredjeplass. Bykle har, som allerede nevnt, minst deltidsarbeid
blant kvinner. På andreplass ligger Kristiansand, etterfulgt av Arendal
og Lillesand. 2
I prosjektet hadde vi også samtaler med ansatte i kommuneadministrasjonene i alle de seks
kommunene vi intervjuet i. I Farsund intervjuet vi også representanter for lokale industri
bedrifter. Samfunnsforskning som kan bidra til å forstå
hvorfor Agder er en lite likestilt landsdel Flere samfunnsforskere har drøftet mulige årsaker til den lave graden av
kjønnslikestilling på Agder, sammenlignet med mange andre deler av
Norge. Basert på en gjennomgang av statistikk og kvalitative intervjuer
med blant annet rundt 120 norske småbarnsforeldre i heterofile parfor-
hold i ulike kommuner på Agder2 i perioden 2003–2005, var jeg med på
en drøfting av mulige årsaker til den høye deltidsandelen blant kvinner i
landsdelen. I rapporten fra forskningen (Magnussen, Mydland & Kvåle,
2005) trakk jeg og mine medforfattere frem utdanningsmønstre som én
mulig årsak. Utdanningslengde har mye å si for kvinners arbeidstid, i
den forstand at kvinners arbeidstid ofte stiger med utdanningslengde
(Kitterød & Rønsen, 2012), og nevnte statistikkgjennomgang viste at
Agder utmerket seg fra landet for øvrig med å ha en lav andel kvinner
med universitets- eller høgskoleutdanning over fire år. Gjennomgangen
viste også at agderregionen utmerket seg med høye andeler personer på
uførepensjon – og samtidig med en noe høy andel kvinner blant perso-
ner på uførepensjon. Selv om dette sannsynligvis handlet mye om mulig
heter på lokale arbeidsmarkeder, nevnte vi også at det vi kalte «kulturelle
faktorer» kunne spille en rolle. Dersom kvinner på Agder jevnt over er 158 kjønnede hverdagsliv og likestillingsutfordringer på agder mer hjem- og familieorienterte enn kvinner i andre deler av landet, og
dersom kvinners investering i familierelasjoner generelt blir vurdert som
mer verdifullt blant folk bosatt på Agder enn folk bosatt andre steder i
landet, så kan dette føre til en lavere terskel for å søke om, og få innvil-
get, uførepensjon. Blekesaune (2012) har gjort kvantitative analyser som
nettopp kan tyde på at kvinners orientering mot det vi kan kalle en tra-
disjonell kvinnerolle ligger bak både deltidsarbeid og høyere risiko for
uførhet. Samtidig tyder annen forskning på at kvinners omsorgsarbeid i
nære relasjoner, som ofte tar form av det Lilleaas kaller å være i «konstant
kroppslig beredskap for andre» kan føre til helseplager (Lilleaas, 2003). Det betyr at den kjønnede arbeidsdelingen på Agder, som sannsynligvis
er mer kjønnet enn mange andre steder i landet, også kan bidra til høye
uføreandeler blant kvinner her – og også for menn. Lilleaas argumenterer
nemlig for at også menns hovedansvar for familieforsørgelsen i såkalte
kjernefamilier innebærer slitasje, og at den samlede slitasjen i slike fami-
lier ville vært mindre dersom ulike typer ansvar var likere fordelt mellom
mann og kvinne. 3
Disse faktorene kan selvfølgelig påvirke hverandre i begge retninger: Høy yrkesaktivitet blant
kvinner kan føre til økt yrkesaktivitet blant kvinner, men høy barnehagedekning kan også med-
føre at kvinner øker sin yrkesaktivitet. Leiras (2006) forskning sannsynliggjør at kvinners yrkes
aktivitet kom før barnehagedekning i Norge, og at det altså primært har vært slik at kvinners
økte yrkesaktivitet har drevet barnehageutbyggingen. Samfunnsforskning som kan bidra til å forstå
hvorfor Agder er en lite likestilt landsdel Mens SSBs likestillingsstatistikk viser at arbeidsdelingen på de offent-
lige arenaene på Agder er særlig kjønnet, viser en kvantitativ studie av
likestilling i hjemmet at vi også er særlig lite likestilte på Agder når det
gjelder husarbeid. Studien viser i tillegg at de kommunene som skårer
høyt på den tidligere likestillingsindeksen, skårer høyt når det gjelder
likestilling i hjemmet, også når forskerne har kontrollert for individuelle
faktorer (Lima & Jensen, 2012). Dette siste funnet tyder på at kollektive
måter å tenke og føle på – det vi kan kalle kultur – også har noe å si for at
Agder skårer dårlig på likestilling. Studien til Lima og Jensen tyder i til-
legg på at det særlig er de rurale områdene av Agder som er preget av lite
likestilt arbeidsdeling i hjemmet, samt at denne arbeidsdelingen i såkalte
kjernefamilier i stor grad preges av kvinnens utdanningsnivå. Mer kon-
kret øker likestillingen i hjemmet i takt med kvinnens utdanningsnivå,
og også slik kan likestilling på Agder handle om klasse. Samtidig finner
Lima og Jensen at heterofile par på Agder, også etter kontroll for blant
annet utdanning og arbeidstid, har en mer ulikestilt arbeidsdeling i
hjemmet enn slike par andre steder i landet. Også dette peker altså mot at 159 kapittel 7 lav likestilling på Agder også handler om regional kultur, og ikke kun om
kultur i ulike klasser. Forfatterne av studien skriver: I tidligere studier har regionale variasjoner i arbeidsdeling hjemme fått liten
oppmerksomhet. Derfor er det interessant at vi finner nokså klare kontraster
mellom tettbygde og spredtbygde strøk, og mellom ulike regioner i Norge når
det gjelder deling av husarbeid. Det er også en klar tendens til at par bosatt
i kommuner som skårer høyt på SSBs likestillingsindeks i gjennomsnitt deler
barneomsorg, og særlig husarbeid, mer likt enn par som bor i kommuner med
lav skåre på indeksen. Tendensene består i stor grad også når vi kontrollerer for
relativ lønn og arbeidstidsdifferanse, noe som peker i retning av at forskjeller
mellom landsdeler i liten grad skyldes lokale variasjoner i arbeidsmarkedet. Det
er nærliggende å spørre om regionale forskjeller i likedeling hjemme snarere
dreier seg om kulturelle forskjeller, ikke minst forskjeller i normer og forvent-
ninger om menns og kvinners atferd og prioriteringer. (Lima & Jensen 2012, 90) Forskernes konklusjon er ganske lik konklusjonen i den nevnte rapporten
fra 2005 (Magnussen, Mydland & Kvåle, 2005). Samfunnsforskning som kan bidra til å forstå
hvorfor Agder er en lite likestilt landsdel Der trakk vi frem trekk
som hadde med regionalt og lokalt arbeidsliv og barnehagedekning å
gjøre. Vi rettet oppmerksomhet mot at Agder hadde en relativt stor andel
ansatte i sekundærnæringer, samt at unge på Agder så ut til å ta noe mer
kjønnstradisjonelle utdanningsvalg enn landsgjennomsnittet. Dette kan
påvirke hvilke arbeidsplasser kvinner ser som attraktive. Både de kvan-
titative og de kvalitative dataene som ble brukt i rapporten tydet på at
kvinners arbeidslivsorientering og yrkesaktivitet var høyere i områder av
agderregionen med mange arbeidsplasser som kvinner antakeligvis fant
særlig attraktive. Vi trakk også frem at barnehagedekning og kvinners
yrkesaktivitet så ut til å samvariere i mange kommuner.3 Likevel endte
også vi opp med å legge aller mest vekt på kulturelle dimensjoner. Én
grunn til dette var at en del statistikk tydet på kulturell annerledeshet Forskernes konklusjon er ganske lik konklusjonen i den nevnte rapporten
fra 2005 (Magnussen, Mydland & Kvåle, 2005). Der trakk vi frem trekk
som hadde med regionalt og lokalt arbeidsliv og barnehagedekning å
gjøre. Vi rettet oppmerksomhet mot at Agder hadde en relativt stor andel
ansatte i sekundærnæringer, samt at unge på Agder så ut til å ta noe mer
kjønnstradisjonelle utdanningsvalg enn landsgjennomsnittet. Dette kan
påvirke hvilke arbeidsplasser kvinner ser som attraktive. Både de kvan-
titative og de kvalitative dataene som ble brukt i rapporten tydet på at
kvinners arbeidslivsorientering og yrkesaktivitet var høyere i områder av
agderregionen med mange arbeidsplasser som kvinner antakeligvis fant
særlig attraktive. Vi trakk også frem at barnehagedekning og kvinners
yrkesaktivitet så ut til å samvariere i mange kommuner.3 Likevel endte
også vi opp med å legge aller mest vekt på kulturelle dimensjoner. Én
grunn til dette var at en del statistikk tydet på kulturell annerledeshet 160 kjønnede hverdagsliv og likestillingsutfordringer på agder på Agder. Rapporten viste til at landsdelen skilte seg ut ved lite støtte
til partiene til venstre på den politiske aksen, ved lavt engasjement for
likestilling, i stor utbredelse av ekteskapet som samlivsform og i høyere
barnetall enn landet for øvrig. Vi nevnte også religiøsitet som et sannsyn-
lig tegn på og/eller årsak til Agders kulturelle annerledeshet, og jeg deltok
senere i en kvantitativ studie av sammenhenger mellom religiøs (kristen)
aktivitet og likestillingsholdninger (Magnussen, Repstad & Urstad, 2012). 4
Fra 2020 inkluderer Lindesnes kommune også det som før det var Mandal og Marnardal kommuner 5
Alle mennene hadde også kreft eller hadde hatt kreft tidligere, siden prosjektet mitt innlednings-
vis var en del av et større paraplyprosjekt om menn med kreft. Samfunnsforskning som kan bidra til å forstå
hvorfor Agder er en lite likestilt landsdel Ved hjelp av surveydata fra 2008 viste vi at andelen religiøst aktive var
markant høyere på Agder enn i andre deler av landet, samt at de religiøst
aktive i landsdelen var betydelig mer skeptiske til likestilling enn det reli-
giøst aktive i andre deler av landet var. Funn i studien tydet også på at det
særlig var aktive i frikirkelige miljøer som var mest likestillingsskeptiske,
uten at dette kunne slås fast. Hovedårsaken til at nevnte rapport fra 2005 endte opp med å rette
fokus mot det som sannsynligvis er kulturelle særpreg ved Agder, var
imidlertid de kvalitative dataene som ble utviklet i forbindelse med pro-
sjektet som rapporten baserte seg på. Selv om informantene i studien ofte
snakket i et språk som ved første blikk kunne se kjønnsnøytralt ut, viste
det samlede datamaterialet at det ble gjort mer indirekte språklige kob-
linger til kjønn og at mange av de vi intervjuet i praksis så ut til å forvente
ganske ulike ting av menn og kvinner som foreldre. Mens kvinner ofte
ble forventet å redusere arbeidstiden for å få «tid med barn» (Ellingsæter,
2005), ble menns hovedforsørgeransvar ofte tatt som en selvfølge, både
av menn og av kvinner. Sitatet under, fra et intervju med en mor bosatt
i rurale strøk i gamle Lindesnes kommune,4 er representativt for slik det
ofte ble snakket om mødres arbeidstid i intervjuene: Altså, vi er jo heldige, mannen min tjener jo veldig bra. Han gjør jo det. Så da
kan jeg være noe hjemme. […] «Guri, sånn vil ikke jeg ha det!» Sånn tenker
jeg om de som jobber fullt. […] Jeg har en venninne som jobber fullt. Og det
vet jeg, at hun må jobbe, for de bygger nytt hus. Det er nok nesten ingen som
jobber fullt altså, av mine venninner, når de har små barn. Men hva skal en
med barn hvis en ikke skal se dem nesten? Jeg vil ikke ha det sånn, men jeg 161 kapittel 7 skjønner jo absolutt de som må. […] Da han (sønnen) gikk i barnehage, da var
der ikke mange som gikk hver dag. Men de som gikk fullt var der fra tidlig til
sent. Huffameg (Ler). En skal jo ikke tro at det en selv gjør nødvendigvis er
best. Men jeg skjønner jo de som må, det er ikke det. En må jo bare være glad at
en ikke trenger å ha det sånn. Samfunnsforskning som kan bidra til å forstå
hvorfor Agder er en lite likestilt landsdel Samtidig viser informanten
bak sitatet over, som mange andre informanter i dette prosjektet, forstå-
else for kvinner som jobber fullt fordi de må, men ikke for kvinner som
jobber fullt fordi de vil. I rapporten koblet vi dette til at mange kvinner
som selv var hjemmeværende eller jobbet redusert, så ut til å forstå lønnet
arbeid som penger og som en mulighet til å ha sosiale relasjoner til andre
enn familiemedlemmer. Forstår man lønnet arbeid på denne måten, er
det forståelig at kvinner som jobber relativt mye, også selv om de ikke
må, forstås som egoistiske og materialistiske – noe de ofte ble i vårt data-
materiale. De kvinnene vi intervjuet som jobbet fullt eller mer, snakket
imidlertid i liten grad om lønnsarbeid som penger og sosial kontakt, men
mer om slikt arbeid og den fagligheten det innebar som en viktig del av
deres identitet – av hvem de anså seg for å være. Spørsmålet om «hva man skal med barn hvis man nesten ikke skal se
dem» er tilsynelatende kjønnsnøytralt, men det er ikke slik at kvinnen
bak sitatet kjenner seg heldig – og antakeligvis moralsk overlegen – når
hun tenker på folk («de») som jobber fullt. Det gjør hun i stedet når hun
tenker på mødre som jobber fullt. Det samme ser ut til å være tilfelle for
mange andre kvinner som ble intervjuet i dette prosjektet, samtidig som
fedres arbeidstid og manglende tid med barn nesten ikke reflekteres over. g
gl
Det er kun når fedre «jobber døgnet rundt» at deres tid brukt på løn-
net arbeid snakkes om i negative vendinger. Samtidig viser informanten
bak sitatet over, som mange andre informanter i dette prosjektet, forstå-
else for kvinner som jobber fullt fordi de må, men ikke for kvinner som
jobber fullt fordi de vil. I rapporten koblet vi dette til at mange kvinner
som selv var hjemmeværende eller jobbet redusert, så ut til å forstå lønnet
arbeid som penger og som en mulighet til å ha sosiale relasjoner til andre
enn familiemedlemmer. Forstår man lønnet arbeid på denne måten, er
det forståelig at kvinner som jobber relativt mye, også selv om de ikke
må, forstås som egoistiske og materialistiske – noe de ofte ble i vårt data-
materiale. Samfunnsforskning som kan bidra til å forstå
hvorfor Agder er en lite likestilt landsdel (Magnussen, Mydland & Kvåle, 2005, s. 155–156) Spørsmålet om «hva man skal med barn hvis man nesten ikke skal se
dem» er tilsynelatende kjønnsnøytralt, men det er ikke slik at kvinnen
bak sitatet kjenner seg heldig – og antakeligvis moralsk overlegen – når
hun tenker på folk («de») som jobber fullt. Det gjør hun i stedet når hun
tenker på mødre som jobber fullt. Det samme ser ut til å være tilfelle for
mange andre kvinner som ble intervjuet i dette prosjektet, samtidig som
fedres arbeidstid og manglende tid med barn nesten ikke reflekteres over. Det er kun når fedre «jobber døgnet rundt» at deres tid brukt på løn-
net arbeid snakkes om i negative vendinger. Samtidig viser informanten
bak sitatet over, som mange andre informanter i dette prosjektet, forstå-
else for kvinner som jobber fullt fordi de må, men ikke for kvinner som
jobber fullt fordi de vil. I rapporten koblet vi dette til at mange kvinner
som selv var hjemmeværende eller jobbet redusert, så ut til å forstå lønnet
arbeid som penger og som en mulighet til å ha sosiale relasjoner til andre
enn familiemedlemmer. Forstår man lønnet arbeid på denne måten, er
det forståelig at kvinner som jobber relativt mye, også selv om de ikke
må, forstås som egoistiske og materialistiske – noe de ofte ble i vårt data-
materiale. De kvinnene vi intervjuet som jobbet fullt eller mer, snakket
imidlertid i liten grad om lønnsarbeid som penger og sosial kontakt, men
mer om slikt arbeid og den fagligheten det innebar som en viktig del av
deres identitet – av hvem de anså seg for å være. Spørsmålet om «hva man skal med barn hvis man nesten ikke skal se
dem» er tilsynelatende kjønnsnøytralt, men det er ikke slik at kvinnen
bak sitatet kjenner seg heldig – og antakeligvis moralsk overlegen – når
hun tenker på folk («de») som jobber fullt. Det gjør hun i stedet når hun
tenker på mødre som jobber fullt. Det samme ser ut til å være tilfelle for
mange andre kvinner som ble intervjuet i dette prosjektet, samtidig som
fedres arbeidstid og manglende tid med barn nesten ikke reflekteres over. Det er kun når fedre «jobber døgnet rundt» at deres tid brukt på løn-
net arbeid snakkes om i negative vendinger. Samfunnsforskning som kan bidra til å forstå
hvorfor Agder er en lite likestilt landsdel De kvinnene vi intervjuet som jobbet fullt eller mer, snakket
imidlertid i liten grad om lønnsarbeid som penger og sosial kontakt, men
mer om slikt arbeid og den fagligheten det innebar som en viktig del av
deres identitet – av hvem de anså seg for å være. At den relativt lave likestillingen på Agder også har med kjønnede for-
ventninger til fedre i kjernefamilier å gjøre, kom tydelig frem i en kvalitativ
studie av menns familieforsørgelse hvor jeg gjorde kvalitative intervjuer
i perioden 2008–2012 (Magnussen, 2015). Jeg intervjuet 12 norske fedre
som var bosatt på Sørlandet og som var eller hadde vært i parforhold med
kvinner,5 og intervjuet nesten alle i flere omganger. Flere norske sosio- 162 kjønnede hverdagsliv og likestillingsutfordringer på agder loger har erklært det som gjerne kalles «forsørgermaskuliniteten» – at
det å være en god familieforsørger forstås som en måte å være en god
livspartner og far på – for død og begravet (se for eksempel Brandth &
Kvande, 2003; Ellingsæter, 1998). I nevnte studie viste jeg imidlertid at
bak et tilsynelatende kjønnsnøytralt språk gjorde de fleste av mine infor-
manter seg til «gode menn» i både egne og andres øyne ved å gjøre mye
og mangfoldig «forsørgerarbeid».6 I sitatet under svarer en mann bosatt i
Kristiansand på mitt spørsmål om hva han tror at heterofile kvinner som
er på utkikk etter en far til sine fremtidige barn, ser etter: Begge mine koner har snakket om at de føler seg trygge hos meg, det har de, så
det med trygghet … Så det er klart, jeg tenker jo litt sånn … Perspektivet blir
liksom litt sånn … En glemmer liksom disse materielle tingene. Det å ha en
mann som kan gå ut på jakt og du vet … kan komme hjem med et bytte uan-
sett om det er dårlig jakt. Det er viktig. Og det å kunne være handy og kunne
fikse ting og ordne ting og ikke sitte i sofaen og si «du, det kan jeg ikke greie. Vi må ringe etter noen». Det tror jeg er veldig viktig. Det tror jeg. (Magnussen,
2015, s. 94) Som mange av de andre informantene i denne studien, gjorde informan-
ten bak sitatet over mye fysisk, mentalt og emosjonelt «arbeid» (Smith,
2005) for å produsere og forvalte økonomiske ressurser på måter som kom
familien hans til gode. 6
I studien brukte jeg begreper fra Dorothy Smiths (2005) sosiologiske tenke- og gjøremåte insti-
tusjonell etnografi. Institusjonell-etnografisk forskning starter som regel ut med å utforske et be-
stemt «arbeid». Arbeid forstås i bred forstand – som noe folk gjør som krever tid og krefter, som
de mener å gjøre, som gjøres under spesifikke omstendigheter, med ulike metoder og verktøy, og
som de kanskje må tenke over (Smith, 2005, s. 151–152). 7
Årsakene til denne situasjonen er antakeligvis mange. Informanten bak sitatet over refererer til
at en «glemmer disse materielle tingene», og jeg mener at både velstandsnivået i Norge og den
norske velferdsstatens sikkerhetsnett bidrar til at disse tingene kan glemmes. Gullestad (2002)
mente at «oppnådd kjønnslikestilling» utgjør en sentral del av norsk selvforståelse, og jeg me-
ner at en dominerende likestillingsdiskurs bidrar til nevnte tilsynelatende kjønnsnøytrale språk.
Dette gjør kjønnede forventninger vanskeligere å se enn hva som var tilfelle i 1950-årene, da
mange kvinner primært var husmødre mens mange menn var eneforsørgere. Dette bidrar til en
situasjon hvor vi i dag aller mest legger merke til «de andres» likestillingsutfordringer (Gullestad,
2002). Ikke minst mener jeg at en viktig grunn til forsørgermaskulinitetens usynlighet handler
om at den tidlige sosiologiske kvinneforskningen adopterte en forståelse av familieforsørgelse og
lønnsarbeid som var basert i kvinners erfaringer mer enn i menns, samt at denne forståelsen ser
ut til å ha blitt overtatt også av nordisk forskning på menn og maskuliniteter (Magnussen, 2015).
Jeg mener at denne forståelsen aller mest ser ut til å være basert i middelklassekvinners erfaring. Samfunnsforskning som kan bidra til å forstå
hvorfor Agder er en lite likestilt landsdel Også for mange andre av informantene i denne
studien handlet dette blant annet om det arbeidet som nevnes i sitatet
over – om å sikre og maksimere inntekt, samt å vedlikeholde, pusse opp,
bygge på og bygge om familiens bolig og feriebolig(er) selv for å få så mye
«hjemskaping» (Aarseth, 2008) som mulig med pengene som var til rådig-
het. Den omfattende og mangfoldige forsørgerpraksisen til informanten
bak sitatet over var typisk for mennene som ble intervjuet. Samtidig var
denne informantens forståelse og italesettelse av denne praksisen utypisk. 163 kapittel 7 De fleste av mennene jeg intervjuet koblet nemlig ikke eksplisitt det å
være en god mann sammen med det å være en god familieforsørger. Mer
typisk var det at de gjorde mye familieforsørgelse, syntes dette arbeidet
var viktig og meningsfullt og fortalte om erfaringer som tilsa at de også
koblet det til mannlighet, men i liten grad hadde reflektert over eller itale
satt familieforsørgelse som «mannlighetsarbeid» før jeg intervjuet dem. Familieforsørgelsen til mennene jeg intervjuet i forbindelse med denne
studien fremstod med andre ord som kjønnet familiearbeid som i stor
grad var taust og kroppsliggjort. Jeg mener vi har god grunn til å tro at
også menn andre steder i Norge gjør mer slikt arbeid enn det vi gjerne
tror – og at det også er viktigere for deres opplevelse av mannlighet enn
det vi ofte har trodd til nå.7 Samtidig har vi god grunn til å tro at både
omfanget av dette arbeidet og dets koblinger til mannlighet antakeligvis
er større og sterkere på Agder enn mange andre steder i Norge, og at noe
av landsdelens kulturelle annerledeshet handler om nettopp dette. 8
I Bykle var faktisk flere kvinner enn menn yrkesaktive da vi skrev 2005-rapporten, noe som var
veldig atypisk i agdersammenheng. I 2018 var Bykle fremdeles den kommunen på Agder med
den laveste andelen kvinner som jobber redusert, mens mange bygdekommuner hadde større
andeler kvinner som jobber redusert enn hva Farsund hadde. Farsund var imidlertid fremdeles
en av de kommunene på Agder hvor forskjellen i menns og kvinners deltidsarbeid var høyest.
Det var altså en av kommunene i landsdelen hvor kjønnsforskjellen i arbeidstid var størst (se
tabell 4 i dette kapitlet). Samfunnsforskning som kan bidra til å forstå
likestillingsvariasjoner innad i agderregionen Forskningen jeg presenterte i forrige avsnitt viser at de koblingene mel-
lom kvinnelighet og omsorgsarbeid og mannlighet og forsørgerarbeid
som ble styrket gjennom moderniseringen av Norge (Solheim, 2007)
fremdeles synes å ha en særlig sterk formende kraft på menns og kvinners
hverdagsliv på Agder. Samtidig viser både statistikk og forskning at der er 164 kjønnede hverdagsliv og likestillingsutfordringer på agder forskjeller i hvor kjønnede hverdagene til menn og kvinner i ulike deler av
regionen er. I forbindelse med arbeidet med den nevnte 2005-rapporten
(Magnussen, Mydland & Kvåle, 2005) utviklet jeg og mine medforfattere
data som skulle si noe om slike variasjoner. Vi gjorde blant annet inter-
vjuer i Farsund og Bykle – to kommuner som skåret veldig forskjellig på
SSBs likestillingsindeks. Mens Bykle ifølge denne tidligere indeksen lå
helt i norgesteten i likestilling, kom Farsund ut som en av Norges minst
likestilte kommuner – og forskjellen i kvinners arbeidstid mellom kom-
munene var veldig stor.8 Ifølge statistikken fra SSB var disse kommunene
veldig ulike når det gjaldt både kommuneøkonomi, næringsstruktur,
arbeidsledighets- og uførhetsgrad, utdanningsnivå i befolkningen, barne
hagedekning, kvinneandel i befolkningen og politisk stemmegivning. I denne delen av kapitlet beskriver jeg nærmere forskjellene mellom disse
to kommunene som kom frem i løpet av denne forskningen. Jeg nevner
også noen mulige historiske forklaringer på de nevnte forskjellene mel-
lom Bykle og Farsund, for slik å legge til rette for videre refleksjon over
likestillingsforskjeller internt i agderregionen og deres mulige historiske
årsaker. Disse forklaringene ble vi presentert for under forskningen, eller
da vi presenterte denne for politikere og byråkrater i de ulike kommu-
nene vi gjorde forskningen vår i. Vår gjennomgang av statistikk i forbindelse med forskningen som for-
midles i nevnte 2005-rapport viste at Bykle kommune hadde eksepsjonelt
høye frie inntekter sammenlignet med andre kommuner på Agder, mens
Farsund lå rundt fylkesgjennomsnittet i daværende Vest-Agder. Den gode
kommuneøkonomien bidro antakeligvis til at Bykle hadde en særlig høy
andel av arbeidsstyrken ansatt i offentlig sektor. Farsund, derimot, hadde
færre arbeidsplasser i offentlig sektor enn gjennomsnittet for Vest-Agder. I Bykle ble vi fortalt at kommunen i stor grad tilbød fulltidsstillinger i
offentlig sektor. Vi ble også fortalt at barnehagene i kommunen hadde 165 kapittel 7 pedagoger i assistentstillingene sine, samt at kapasiteten til å kunne ta
imot barn var så god at foreldre kunne søke om barnehageplass den ene
dagen og møte opp med barnet/barna den neste. Samfunnsforskning som kan bidra til å forstå
likestillingsvariasjoner innad i agderregionen Barnehagedekningen i
Bykle var også eksepsjonelt høy i agdersammenheng. Situasjonen frem-
stod som veldig annerledes i Farsund. Kommunen hadde mye lavere
barnehagedekning enn hva som var tilfelle i Bykle, og også betraktelig
lavere enn gjennomsnittet for Vest-Agder, og vi fikk høre om en ny barne-
hage i kommunen som hadde utlyst stillinger og fått 115 kvinnelige søkere
til disse. I Farsund var det også flere kvinner som snakket varmt om å
være mye hjemme med barn som fortalte at de ville tatt imot et jobb-
tilbud fra denne barnehagen om de hadde fått det, også selv om de ble
tvunget til å jobbe fulltid. Dette var ett av flere tegn som kunne tyde på
at der var en del skjult arbeidsledighet i Farsund. Dette funnet viste også
at kvinnene vi intervjuet kunne begrunne det å være hjemme med barn
eller jobbe redusert ved å referere til «barns beste» fordi dette satte dem i
en verdig fortellerposisjon, mens deres valg i praksis også viste tegn til å
være formet av for eksempel mulighetene som det lokale arbeidsmarke-
det tilbød. Når det kom til næringsstruktur, viste statistikken fra SSB at Bykle
hadde langt flere arbeidsplasser innen tertiærnæringer (mye på grunn
av vinterturisme) enn Farsund hadde, mens en mye større andel av
arbeidsplassene i Farsund var innenfor industribedrifter. Dette betød
antakeligvis mye for forskjellene i kvinners yrkesaktivitet mellom de to
kommunene. I Bykle var der også et betydelig kvinneoverskudd i befolk-
ningen, noe som var veldig atypisk sett i forhold til andre innlands
kommuner på Agder. Mye av dette kan antakeligvis forklares med et
godt arbeidsmarked innenfor reiselivsnæringen i Bykle. Flere vi snakket
med forklarte at kommunen hadde netto tilflytting, og at veldig mange
av de som kom flyttende, kom nettopp fordi de hadde fått jobb der. Alt i
alt så det altså ut til at Bykle hadde et lokalt arbeidsmarked med mange
jobber som kvinner tradisjonelt har orientert seg mot, både i offentlig
og privat sektor, mens dette ikke syntes å være tilfelle i Farsund. En slik
konklusjon støttes også av at Farsund hadde en veldig lav kvinneandel
i sin befolkning, ikke minst sammenlignet med andre bykommuner
langs kysten. Det er ikke usannsynlig at få arbeidsplasser som kvinner 166 kjønnede hverdagsliv og likestillingsutfordringer på agder tradisjonelt har orientert seg mot bidro til å gjøre Farsund til en relativt
lite attraktiv bokommune for kvinner. Samfunnsforskning som kan bidra til å forstå
likestillingsvariasjoner innad i agderregionen De vi snakket med i kommune
administrasjonen i Farsund og lokal industri la selv stor vekt på mangelen
på såkalte kompetansearbeidsplasser i kommunen når de skulle forklare
det sterkt kjønnsdelte lokale arbeidslivet. Samlet sett har kvinner høyere
utdanning enn menn, og utdanningsnivået blant befolkningen i Bykle
var også betraktelig høyere enn hva som gjaldt for Farsund. Det skal også
sies at selv om arbeidsledigheten ikke var særlig høy da vi gjorde våre
intervjuer i Farsund, ble vi fortalt at de mange industriarbeidsplassene
gjorde at ledigheten kunne svinge ganske mye – i tråd med internasjonale
konjunkturer. Bykle fremstod altså også som å ha et mer stabilt arbeids-
marked enn det Farsund hadde. Ikke minst er det grunn til å tro at der
alt i alt ofte var forskjeller mellom å jobbe fullt i Farsund og å jobbe fullt
i Bykle. Mye av industrien i Farsund så ut til å være preget av de mange
utenlandske eierne. En del menn fortalte for eksempel at de måtte være
tilgjengelige på tidspunkter hvor kollegaer i andre land var på jobb, og
at det var upopulært å være hjemme med syke barn. Det kan tyde på en
kultur hvor menn forventes å være i konstant kroppslig beredskap for
jobben (Lilleaas, 2003). Representanter for Bykle kommune, på sin side,
fortalte at de prøvde å legge til rette for fleksibilitet i form av for eksem-
pel hjemmekontor dersom ansatte hadde syke barn. Vi vet ikke noe om
hvordan dette forholdt seg i turistnæringen, men at kvinner utgjorde en
så stor del av arbeidsstyrken i Bykle betød antakeligvis uansett en høyere
toleranse for å kunne tilpasse lønnsarbeidet etter familiebehov enn hva
som var tilfelle i Farsund. Samtidig som der syntes å være en del økonomiske og arbeidslivs
messige årsaker til at Bykle og Farsund skåret så ulikt på likestilling
da jeg og mine medforfattere skrev nevnte rapport i 2005, var der også
noen statistiske tegn til kulturforskjeller mellom de to kommunene. Mens det store innslaget av industriarbeidsplasser kunne ført til en stor
andel stemmer til politiske partier på venstresiden av den politiske aksen
i Farsund, var dette ikke tilfelle. I stedet utmerket kommunen seg ved
å være den kommunen på Agder som hadde høyest andel stemmer til
enten Høyre eller Fremskrittspartiet. Samfunnsforskning som kan bidra til å forstå
likestillingsvariasjoner innad i agderregionen Bykle, på sin side, utmerket seg
ved å være en kommune med relativt lav andel stemmer til partier i det 167 kapittel 7 politiske sentrum og på borgerlig side, sammenlignet med andre agder-
kommuner. Til tross for slike statistiske tegn på kulturforskjeller, var det
likevel fascinerende å oppleve noen av disse forskjellene i intervjuene jeg
og kolleger gjorde. Vi dro rett fra intervjuing i Farsund til intervjuing i
Bykle, en geografisk distanse vi la bak oss ved en biltur på rundt tre timer. Barndoms- og morsidealene i de to kommunene fremstod imidlertid som
fundamentalt forskjellige, og det som fremstod som selvsagt, naturlig og
bra i den ene kommunen ble ikke en gang nevnt i den andre. Mens mange
kvinner i Farsund for eksempel var opptatt av å legitimere at de i det hele
tatt gjorde noe lønnsarbeid, og ikke var hjemme på fulltid, tok kvinnene
vi intervjuet i Bykle fulltidsarbeid som en selvfølge. Flere av dem kikket
spørrende på oss når vi spurte hvorfor de jobbet fullt – ikke ulikt mange
menn vi stilte det samme spørsmålet til. Og mens en del kvinner i Far-
sund snakket om foreldre (mødre) som hadde barna i barnehage på full-
tid i harde ordelag, hørte vi ingen slike beskrivelser i Bykle. politiske sentrum og på borgerlig side, sammenlignet med andre agder-
kommuner. Til tross for slike statistiske tegn på kulturforskjeller, var det
likevel fascinerende å oppleve noen av disse forskjellene i intervjuene jeg
og kolleger gjorde. Vi dro rett fra intervjuing i Farsund til intervjuing i
Bykle, en geografisk distanse vi la bak oss ved en biltur på rundt tre timer. Diskusjonene som kom i kjølvannet av disse intervjuene, når dataene
og våre foreløpige analyser ble presentert for kommunestyrene og byrå-
krater i de to kommunene, handlet i stor grad om lange historiske linjer. I Farsund mente flere at en husmorkultur hadde «satt seg» på grunn av
god husholdningsøkonomi historisk sett. Dette hadde etter sigende gjort
at mange gifte kvinner, selv om mange av deres ektemenn var mye borte
på grunn av skipsfart, slapp å ta lønnet arbeid, men i stedet viet seg til reli-
giøst frivillig arbeid, for eksempel knyttet til misjons- og avholdssaken. 9
Det skal nevnes at vi ble fortalt at der var en del kristne miljøer også i Bykle kommune. De vi
snakket med om dette kunne imidlertid ikke se noen koblinger mellom kristen religiøs aktivitet
og kvinners arbeidstid ved at kvinner som var aktive i religiøs aktivitet oftere enn andre kvinner
jobbet redusert eller var hjemmeværende. I samtaler og intervjuer i Farsund kom vi ikke inn på
religiøsitet. Samfunnsforskning som kan bidra til å forstå
likestillingsvariasjoner innad i agderregionen Idealet om den funksjonsdelte kjernefamilien med hjemmeværende mor
og eneforsørgende far – et ideal som vokste i styrke i Vesten fra midten av
1800-tallet og stod sterkt i Norge allerede på 1920-tallet – var opprinnelig
overklassens idealer (Haavet, 1991; Seccombe, 1993), og enkelte vi snakket
med i forbindelse med forskningen vår omtalte Farsund som en by som
tidligere hadde et «aristokrati» knyttet til skipsfart. I Bykle ble det sagt at husholdningsøkonomien før kraftutbyggingen
var så dårlig at ingen hadde råd til å la være å jobbe, og at både menn
og kvinner jobbet hardt på små gårdsbruk. Da kraftutbyggingen kom,
kommunens inntekter økte enormt og det ble etablert mange stillinger
i offentlig sektor lokalt, gikk kvinnene visstnok rett fra gårdsarbeid og
inn i slike jobber. Dermed var der ingen husmorperiode i Bykle, mente 168 kjønnede hverdagsliv og likestillingsutfordringer på agder flere. I tillegg mente en del informanter i Bykle, men også i Åmli, at
agderkommunene som ligger lengst fra kyststripa er mer likestilte fordi
disse gjennom historien ikke ble så preget av de religiøse tenkemåtene
og praksisene som preget «bibelbeltet» langs kysten av Agder.9 Tidligere
forskning har vist at det nettopp er kyststrøkene på Agder som er aller
mest preget av religiøs (kristen) aktivitet (Repstad, 2002). I rapporten fra
2005 spurte jeg og mine medforfattere om dette kunne være noe av grun-
nen til at en del bykommuner på Agder hadde ganske lav yrkesaktivitet
og arbeidstid for kvinner, sett opp mot de relativt mangfoldige arbeids-
markedene mange av disse byene tross alt har, sammenlignet med mange
bygdekommuner. Vi spurte også om dette kunne være en grunn til at
byenes pendlingsomland kunne se ut til å være aller minst likestilte når
det kom til yrkesaktivitet og arbeidstid – fordi folk i disse delene av Agder
kanskje delte mange av de samme idealene som folk i bykommunene,
og samtidig hadde mindre og langt mer ensidige lokale arbeidsmarke-
der. Våre intervjuer tydet på at kvinner var mindre pendlingsvillige enn
menn, og dette kunne i så fall også bidra til å forsterke en slik tendens. Avslutning Statistikken og forskningen jeg har gått gjennom i dette kapitlet gir god
grunn til å tro at både regionale særtrekk ved Agder og variasjoner innad
i landsdelen når det kommer til kjønnede hverdagsliv og likestilling har
mye med økonomi, næringsstrukturer og arbeidsmarkeder å gjøre. Slike
strukturerende krefter former de valgene folk tar i forhold til arbeid «ute»
og hjemme, og vi finner også ulike idealer og praksiser knyttet til barn-
dom, foreldreskap og familieliv i ulike sosiale lag (Lareau, 2003; Stefansen,
2011). Samtidig tyder også statistikken og forskningen jeg har gått gjen-
nom på at vi har god grunn til å tro at både regionens særtrekk og interne
variasjoner har å gjøre med kulturforskjeller som ikke uttømmende kan 169 kapittel 7 forklares med klasseforskjeller. Mye tyder på at slike kulturforskjeller
blant annet kan ha med religiøst liv på Agder å gjøre. I neste kapittel
skriver Bjørg Seland om nettopp dette, ved hjelp av historisk forskning. Samtidig bidrar Seland til å ytterligere øke kompleksiteten i refleksjonene
rundt hva som har gjort Sørlandet til et likestillingsmessig annerledes-
land i norsk sammenheng. Det gjør hun ved å bringe inn enda flere trekk
ved Agder og landsdelens befolkning som kan se ut til å ha spilt en rolle
for dette gjennom historien. Litteratur Blekesaune, M. (2012). Kjønnsroller og uførepensjonering. Tidsskrift for
samfunnsforskning, 53(1), 34–48. https://www.idunn.no/tfs/2012/01/art07 Brandth, B. & Kvande, E. (2003). Fleksible fedre. Maskulinitet, arbeid, velferdsstat. Universitetsforlaget. Ellingsæter, A. L. (1998). Dual breadwinner societies. Provider models in
the Scandinavian welfare states. Acta Sociologica, 41(1), 59–76. https://www.jstor.org/stable/4201061 Ellingsæter, A. L. (2005). De «nye» mødrene og remoralisering av moderskapet. Nytt Norsk Tidsskrift, 22(4), 373–382. https://www.idunn.no/nnt/2005/04/de_nye_
modrene_og_remoralisering_av_moderskapet Gullestad, M. (2002). Det norske sett med nye øyne: Kritisk analyse av norsk
innvandringsdebatt. Universitetsforlaget. Haavet, I. E. (1991). Et respektabelt liv – arbeiderfamiliene og arbeiderbevegelsen
under industrialiseringsprosessen. I B. G. Alver, L. Mikaelsson & I. Blom (Red.),
KvinneMinnebok til Ida Blom på 60-årsdagen, 20. februar 1991 (s. 105–124). Universitetet i Bergen, Senter for humanistisk kvinneforskning. Kjeldstad, R. & Kristiansen, J. E. (2001). Constructing a regional gender equality
index: Reflections on a first experience with Norwegian data. Statistical Journal
of the United Nations Economic Commission for Europe, 18(1), 41–49. https://doi. org/10.3233/SJU-2001-18103 Kitterød, H. R. & Rønsen, M. (2012). Kvinner i arbeid ute og hjemme. Endring og
ulikhet. I A. L. Ellingsæter & K. Widerberg (Red.), Velferdsstatens familier. Nye sosiologiske perspektiver (s. 161–190). Gyldendal Akademisk. Lareau, A. (2003). Unequal childhoods class, race, and family life. University of
California Press. Leira, A. (2006). Parenthood change and policy reform in Scandinavia, 1970s–2000s. Leira, A. (2006). Parenthood change and policy reform in Scandinavia, 1970s–2000s. I A. L. Ellingsæter & A. Leira (Red.), Politicising parenthood in Scandinavia. I A. L. Ellingsæter & A. Leira (Red.), Politicising parenthood in Scandinavia. 170 kjønnede hverdagsliv og likestillingsutfordringer på agder Gender relations in welfare states (s. 27–52). Policy Press. https://doi.org/ 10.2307/j. ctt9qgtw3.7 Lilleaas, U.-B. (2003). Fra en kropp i ustand til kroppen i det moderne
[Doktorgradsavhandling]. Universitetet i Oslo. Lilleaas, U.-B. (2003). Fra en kropp i ustand til kroppen i det moderne
[Doktorgradsavhandling]. Universitetet i Oslo. Lima, I. & Jensen, R. S. (2012). Arbeidsdeling hjemme: hvilken betydning har
livsfase, yrkestilknytning, sosial klasse og bosted? I T. Hansen & B. Slagsvold
(Red.), Likestilling hjemme (NOVA rapport 8/2012, s. 43–92). http://nova.no/asset/5912/1/5912_1.pdf Magnussen, M.-L. (2012). Likestilling på Agder 2000–2010 (Prosjektrapport
nr. 1/2012). Agderforskning. Magnussen, M.-L. (2015). Familieforsørgelse i menns hverdag
[Doktorgradsavhandling, Universitetet i Oslo]. DUO vitenarkiv. http://urn.nb.no/URN:NBN:no-52713 Magnussen, M.-L., Mydland, T. S. & Kvåle, G. (2005). Arbeid ute og hjemme. Sørlandske mødres valg og vurderinger (Rapport fra prosjektet Likestilling
og arbeidsliv på Agder). Agderforskning. https://senterforlikestilling.org/
wp-content/uploads/2010/08/Arbeid-ute-og-hjemme-S%C3%B8rlandske-
m%C3%B8dres-valg-og-vurderinger.pdf Magnussen, M.-L., Repstad, P. & Urstad, S. (2012). Sitering av dette kapitlet: Seland, B. (2020). Konservative holdninger til likestilling på Sørlandet: noen
kulturhistoriske aspekter. I Johnsen, B.E. og Vadum, K. (red.), Grenseløst Agder. Det som skilte og det som
bandt (s. 172–195). Oslo: Cappelen Damm Akademisk. https://doi.org/10.23865/noasp.111
Lisens: CC BY-NC-ND. 1
Referer til Statistisk sentralbyrås målesystemer, se Magnussens kapittel i denne antologien. Prak-
tisk avklaring: 1) Statistikk det vises til, bygger på fylkes- og kommuneinndelingen før 2020;
den gamle fylkesinndelingen er derfor lagt til grunn for omtale av regionale forskjeller i dette
kapitlet. 2) Begrepet likestilling er i dette kapitlet gjennomgående brukt om likestilling mellom
kjønn. Litteratur Skepsis til likestilling på
Sørlandet – et resultat av religion? Tidsskrift for kjønnsforskning, 36(3/4), 204–222. https://www.idunn.no/tfk/2012/03-04/skepsis_til_likestilling_p_srlandet_-_et_
resultat_av_rel Repstad, P. (2002). Mellom inderlighet og spissborgerskap. En samfunnsforsker ser
på Sørlandspietismen. I H. Inntjore (Red.), Agderkirken (Skriftserien, nr. 83). Høgskolen i Agder. Seccombe, W. (1993). Weathering the storm. Working-class families from the industrial
revolution to the fertility decline. Verso. Senter for likestilling. (2016). Likestillingsmonitor Agder. 2008–2015. Universitetet
i Agder. https://senterforlikestilling.org/wp-content/uploads/2017/01/
Likestillingsmonitor-2008-2015-high.pdf
Smith, D. E. (2005). Institutional ethnography. A sociology for people. AltaMira. Solheim J (2007) Kjønn og modernitet Pax Statistisk sentralbyrå. (2019, 5. desember). Indikatorer for kjønnslikestilling i
kommunene [Statistikk]. https://www.ssb.no/befolkning/statistikker/likekom Statistisk sentralbyrå. (2019, 5. desember). Indikatorer for kjønnslikestilling i
kommunene [Statistikk]. https://www.ssb.no/befolkning/statistikker/likekom Stefansen, K. (2011). Foreldreskap i småbarnsfamilien. Klassekultur og sosial
reproduksjon [Doktorgradsavhandling], Universitetet i Oslo. http://urn.nb.no/URN:NBN:no-30380 Stefansen, K. (2011). Foreldreskap i småbarnsfamilien. Klassekultur og sosial
reproduksjon [Doktorgradsavhandling], Universitetet i Oslo. http://urn.nb.no/URN:NBN:no-30380 Aarseth, H. (2008). Hjemskapingens moderne magi [Doktorgradsavhandling]. Universitetet i Oslo. Aarseth, H. (2008). Hjemskapingens moderne magi [Doktorgradsavhandling]. Universitetet i Oslo. 171 2
Ryen 2002 kapittel 8
Konservative holdninger
til likestilling på Sørlandet:
noen kulturhistoriske aspekter kapittel 8 4
De mest relevante samfunnsfaglige studiene fra Agder er publisert i Ellingsen & Lilleaas 2010;
Magnussen & Repstad 2010; Magnussen, Repstad & Urstad 2012. Se også Magnussens kapittel i
denne antologien. kapittel 8 Bjørg Seland Agder skårer svakt i all statistikk som måler likestilling mellom kjønn
i Norge. Fra den første «likestillingsindeksen» ble presentert i 1999, og
i seinere år gjennom «indikatorer for kjønnslikestilling i kommunene»,
har denne landsdelen ligget på bunnplass.1 Den som leter etter forklarin-
ger på dette, må selvsagt vurdere et større bilde, der skiftende vilkår for
økonomi og næringsliv har skapt de grunnleggende betingelsene. Men
selv når hensynet til slike forhold er lagt inn i sammenligningsgrunn
laget, skiller Agder seg ut. Sørlendingene synes å stå for en konservatisme
en vanskelig kan forklare uten å søke mot mindre håndgripelige faktorer,
som kultur og mentalitet. t Litt for ofte ser vi at religion får stå som forklaring på ‘alt som er galt’
i agderfylkene: Det må være den sørlandske pietismen som ennå hem-
mer sosial endring og ønskelig utvikling. Mediene har i høy grad bidratt
til lettbeinte fortolkninger av denne typen. Slike kjappe koplinger kan
skygge for utsyn til et videre og mer komplekst felt av påvirknings
faktorer, ikke minst når det gjelder holdninger til likestilling.2 Sosiolo- 172 konservative holdninger til likestilling på sørlandet giske studier på internasjonalt plan viser like fullt at religiøst engasjement
generelt henger sammen med konservatisme i synet på kjønnsroller.3 Som
May-Linda Magnussen viser i sitt kapittel i denne antologien, har flere
samfunnsfaglige studier i seinere tid dokumentert slike sammenhenger
også i norsk og sørlandsk kontekst.4 Kjønnsperspektiver er etter hvert blitt mer integrert i historiefaglig
forskning, men så langt har historikere vist liten interesse for det religiøse
feltet. Noe har vi likevel å bygge på, og med tilfang fra religionssosiologisk
og kirkehistorisk litteratur har vi et visst grunnlag for innsikt. I dette
kapitlet vil jeg søke å utdype forståelsen av kristelige kjønnsrollemønstre
på 1800- og 1900-tallet, og trekke noen linjer fram mot vår tid. Videre
vil jeg vise til noen særtrekk ved sørlandsk kulturhistorie som kan bidra
til å forklare at konservative holdninger til likestilling så sterkt har holdt
stand nettopp i denne landsdelen. Jeg vil også knytte an til noen spørsmål
som sosiologer på mer generell basis har stilt om religiøse kjønnsregimer
i dagens vestlige samfunn: Hvorfor er det slik at kvinner i visse miljøer
ennå ser ut til å ville tilpasse seg konservative normer? 3
Woodhead 2007 3
Woodhead 2007 5
Seland 2020; Seland & Aagedal 2008
6
Seland & Aagedal 2008: 29–30
7
Seland 2006: 271 ff.
8
De største organisasjonene er Det Norske Misjonsselskap (NMS) stiftet 1842, Det Norske Lutherske
Indremisjonsselskap (IM) stiftet 1891, Norsk Luthersk Misjonssamband (NLM) stiftet 1891 og Det
Vestlandske Indremisjonsforbund (DVI) stiftet 1898. DVI endret i 2000 navn til Indremisjons
forbundet (ImF); IM ble i 2001 fusjonert med mindre organisasjoner i Normisjon; NLM ble
stiftet under navnet Det norske Lutherske Kinamisjonsforbund, navneendring 1949. 5
Seland 2020; Seland & Aagedal 2008 Historisk bakgrunn og sentrale begreper Den kristelige lekmannsbevegelsen har en historie som går tilbake til
1790-tallet, da bondesønnen Hans Nielsen Hauge trådte fram som leder
for en folkelig opposisjon innenfor statskirken. Etter at konventikkel
plakaten var opphevet i 1842, sto lekfolket fritt til å danne sine egne
sammenslutninger på basis av den offentlige kirkens lutherske lære. Da
Stortinget tre år seinere vedtok den første dissenterloven, lå veien åpen for
å danne frikirkelige samfunn. De kulturelle bindingene var likevel så sterke at størstedelen av lek
folket valgte å organisere seg i frivillige organisasjoner innenfor stats
kirken. I første omgang var engasjementet knyttet til ytre misjon, i
samtiden kjent som «hedningemisjon». Fra om lag 1860 vokste interessen 173 kapittel 8 for indre misjon, der målet var å motvirke sekularisering og fremme en
mer inderliggjort kristentro i Norge. Lekmannsrørsla hadde oppslutning
i alle deler av landet, men kom på særeget vis til å prege kultur og sam-
funnsliv i de sørlige og vestlige kystområdene.5 I en tidlig fase var lekmannsrørsla inspirert av tysk pietisme. Mot slut-
ten av århundret kom impulsene i sterkere grad fra britiske og anglo
amerikanske vekkelsesmiljøer. Mens pietismen tradisjonelt hadde
forkynt en tung og møysommelig vei til salighet, presenterte 1800-tallets
britiske og amerikanske predikanter et frelsesbudskap som dempet trus-
selen om Guds dom og framhevet håpet om nåde. Slik senket de terskelen
for den enkelte som søkte vekkelsesflokkens fellesskap. Disse nyevange-
lismens predikanter dyrket også en særlig pågående form for agitasjon. Med dette sporskiftet i norsk vekkelsekristendom kom også det brede
gjennombruddet for lekmannsbevegelsen.6 Lokalt var de kristelige foreningene organisert innenfor den kirkelige
menigheten. Men med bedehuset som ramme for et tettere fellesskap,
markerte lekfolket seg som en eksklusiv flokk av «rettroende». De holdt
fast ved en pietisme de så som sannere og renere enn den trosforkynnel-
sen kirken i alminnelighet sto for. På det lokale nivået kunne foreninger
tilsluttet ulike misjonsorganisasjoner gå sammen om visse tiltak – eller
de profilerte seg i mer eller mindre skarp konkurranse med hverandre.7 Begrepene lekmannsrørsla, lekmannsbevegelsen og misjonsbevegelsen
blir i dette kapitlet brukt synonymt, som felles benevnelser for kristelige
organisasjoner som arbeider for ytre og indre misjon.8 Alle organisasjo-
nene hadde i utgangspunktet retningslinjer som tilsa at bare menn skulle
tilkjennes fulle medlemsretter. Gjennom 1900-tallet har de stegvis og med
ulik progresjon også gitt kvinner stemmerett. Spørsmål om valgbarhet 174 konservative holdninger til likestilling på sørlandet har vært mer problematisk. Historisk bakgrunn og sentrale begreper Enkelte misjonsorganisasjoner har ennå i dag
formelle barrierer mot full kjønnsmessig likestilling.9 I vår tid er «kristne organisasjoner» blitt den vanlige betegnelsen for
frivillige sammenslutninger som uttrykkelig erklærer kristne verdier
som fundament for sin virksomhet. I tidligere faser av lekmannsrørslas
historie ble tilsvarende sammenslutninger omtalt som «kristelige». Når
jeg velger å nytte den opprinnelige benevnelsen, er det fordi den har
autentisitet for størstedelen av 1800- og 1900-tallet, og fordi det gjelder en
avgrenset flokk av kristne, samlet om en pietistisk trostolkning. Både av faglige og praktiske grunner er det empiriske grunnlaget for
denne framstillingen stort sett avgrenset til bedehuskulturen. Den har
jo også i historisk perspektiv stått for det mest dominerende kristelige
innslaget på Agder, som i landet for øvrig. Frikirkene – her brukt som fel-
les benevnelse for kristne trossamfunn utenfor statskirken – får dermed
mindre oppmerksomhet. Norsk frikirkelighet ble i hovedsak et urbant
fenomen med særlig gjennomslag i de sørøstlige delene av landet. Vi skal
likevel merke oss at frikirker i nyere tid ser ut til å være sterkere preget av
konservative holdninger til likestilling enn det som er gjengs i statskirke-
lige lekmannsmiljøer.10 Bedehuskulturen var utbredt over store deler av landet, så hvorfor
skulle Agder skille seg så tydelig ut ved en kristelig kulturarv? Før vi går
videre vil jeg pirke litt i forestillingene om Agder som ‘annerledeslandet’
– For hvor avvikende var og er egentlig sørlendingene, om vi sikter langs
andre linjer enn å sammenligne denne landsdelen med landet for øvrig? 9
Om kvinners medlemsretter i misjonsorganisasjonene, se Norseth 2007. 10
Ellingsen & Lilleaas 2010; Magnussen & Repstad 2010 9
Om kvinners medlemsretter i misjonsorganisasjonene, se Norseth 2007.
10
Ellingsen & Lilleaas 2010; Magnussen & Repstad 2010 Agder som del av bibelbeltet I de samfunnsfaglige undersøkelsene om religion og kjønnsroller på Sør-
landet, blir denne landsdelen satt opp mot gjennomsnittsverdier for lan-
det, sett under ett. Dette skyldes nok langt på vei at engasjerte forskere
har sørget for å framskaffe mer detaljert informasjon om forhold i agder-
fylkene enn det som umiddelbart er tilgjengelig for andre regioner. På et 175 kapittel 8 Det norske «bibelbeltet» generelt plan reflekterer forskerne også over at dette
kan føre til misvisning; de mener likevel det samlede
materialet bekrefter bildet av Agder som landets mest
konservative landsdel når det gjelder likestilling mel-
lom kjønn.11 t
g
konservative landsdel når det gjelder likestilling mel-
lom kjønn.11
Hvordan får vi dette til å passe med at Rogaland
historisk sett var kjerneområde og spredningssenter
for den folkelige pietismen som også sørlendinger i
sin tid ble grepet av?12 Fra 1840-tallet hadde Stavanger
vært hovedsete for ytre misjon. Da indremisjonen fra
om lag 1870 fikk vind i seglene, var det «vekkelsespres-
ten» Lars Oftedal (1838–1900) fra Stavanger som førte
an. Gjennom bølgene av massevekkelse som gikk over
landet fra ca. 1870 og fram til mellomkrigstiden, fikk
lekmannsbevegelsen stadig bredere oppslutning. Med
basis særlig i indremisjonens organisasjoner ble den
moderne bedehuskulturen skapt. Kulturgeografiske
kart og valgsosiologiske oversikter viser hvordan kyst-
områdene på Sør- og Vestlandet i dette tidsrommet trer fram som det
norske bibelbeltet.13
beltet» Hvordan får vi dette til å passe med at Rogaland
historisk sett var kjerneområde og spredningssenter
for den folkelige pietismen som også sørlendinger i
sin tid ble grepet av?12 Fra 1840-tallet hadde Stavanger
vært hovedsete for ytre misjon. Da indremisjonen fra
om lag 1870 fikk vind i seglene, var det «vekkelsespres-
ten» Lars Oftedal (1838–1900) fra Stavanger som førte
an. Gjennom bølgene av massevekkelse som gikk over
landet fra ca. 1870 og fram til mellomkrigstiden, fikk
lekmannsbevegelsen stadig bredere oppslutning. Med
basis særlig i indremisjonens organisasjoner ble den
moderne bedehuskulturen skapt. 11
Ellingsen & Lilleaas 2010; Magnussen et al. 2012; Magnussen & Repstad 2010
12
Fossåskaret 2015; Furre 1987
13
Seland 2020; Øidne 1957/1986
14
Øidne 1986
15
Det empiriske materialet omfatter statistikk for stemmefordeling ved visse stortingsvalg i tids-
rommet 1891–1953, støtte til forslaget om brennevinsforbud ved folkeavstemningene i 1919 og
1926, samt fylkesvis fordeling av støttegaver til de største misjonsorganisasjonene året 1955.
Øidne (1986) viser dessuten til tall for utbredelse av misjonsforeninger og kristelige blader. 16
Rokkan 1987: 70 ff., 116 ff., 137 ff., 219 ff.
17
Slettan 1992: 167 ff.
18
Fossåskaret 2015: 45
19
Botvar, Repstad & Aagedal 2010; Fossåskaret 2015
20
Fossåskaret 2015 Agder som del av bibelbeltet Kulturgeografiske
kart og valgsosiologiske oversikter viser hvordan kyst-
- og Vestlandet i dette tidsrommet trer fram som det
13 Det norske «bibelbeltet» Det norske «bibelbeltet» Geografen Gabriel Øidne (1918–1991) har i den klassiske artikkelen
«Litt om motsetninga mellom Austlandet og Vestlandet» skissert noen
grunnleggende kulturtrekk som kjennetegner sør- og vestlandske kyst-
strøk.14 Gjennom kombinasjon av ulike typer kildemateriale dokumen-
terer han styrken i engasjementet for avholds- og misjonssaken og viser
til visse valgsosiologiske mønstre.15 På Vestlandet framhever Øidne et
skille mellom det han kaller «Den mørke kyststripa», der pietismen sto
sterkt, og de indre fjordbygdene som sammen med østlandske fjellbygder 176 konservative holdninger til likestilling på sørlandet utgjorde et område preget av en mer frilynt, grundtvigiansk kristendom. De to kulturene Øidne her viser til, profilerte seg gjennom konkurrerende
folkebevegelser: den kristelige lekmannsbevegelsen og norskdomsrørsla,
som favnet om mållag og frilynte ungdomslag. Stilt opp mot storsamfun-
nets dominerende kultur er begge disse bevegelsene å se som motkultu-
rell mobilisering.16 På lokalt nivå kan vi konstatere at tallet på aktive i religiøs forenings-
virksomhet aldri var særlig høyt. For Agder er det antydet at det kunne
dreie seg om ca. 15 prosent av befolkningen i et bygdesamfunn.17 Bede-
huset hadde likevel en sentral plass i folks bevissthet, og vekkelses
kristendommen fikk et gjennomslag som tenderte mot ideologisk
hegemoni. Mange steder var det religiøse innslaget så sterkt integrert i
felleskulturen at «[å] velja bort bedehuset var å velja bort bygda».18 Nyere samfunnsfaglige undersøkelser viser hvordan denne kulturen
ennå i dag preger holdninger og levesett i sør- og vestlandske kyststrøk.19
At ikke bare Agder, men også vestlandsfylkene skårer mer eller mindre
svakt på dagens statistikk for kjønnsmessig likestilling, styrker antakel-
sen om at religiøst engasjement må tillegges vekt som forklaringsfaktor. Men Rogaland, som en gang var den folkelige pietismens høyborg i Norge,
skårer høyere enn Agder. Her kan en anta at de omfattende endringene
i økonomi og næringsliv som har preget nettopp denne regionen gjen-
nom ‘oljealderen’, også har bidratt til betydelige endringer i det allmenne
normverket.20 Agder er altså del av et videre sør- og vestlandsk kulturbelte, der 1800-
og 1900-tallets folkelige pietisme har satt tydeligere spor enn i landet for
øvrig. Mens bibelfundert ideologi tidlig måtte vike for sekularisert rasjo-
nalisme i den offentlige debatten om kvinners samfunnsmessige retter og
plikter, har konservativ teologisk argumentasjon langt opp mot vår egen
tid gitt legitimeringsgrunnlag for bedehusets kjønnsroller. 177 kapittel 8 21
Slettan 1998: 91
22
Seland 2009
23
Se Tjelle 1999 om kvinnenes innsats for økonomien i Det Norske Misjonsselskap (NMS).
24
Seland 2006: 299–300 Den tradisjonelle misjonskvinnerollen Kvinnene utgjorde alltid et flertall av dem som sluttet seg til lekmannsrørslas
organisasjoner.21 Både i ytre og indre misjon var de tildelt visse arbeidsopp-
gaver. Kvinnene skulle først og fremst arbeide for å skaffe midler til misjons-
virksomhet og til drift av organisasjonene på sentralt og lokalt nivå. Videre
var det forventet at de stilte med frivillig innsats rundt all virksomhet på
bedehuset, og at de fylte benkeradene i salen når lokale og tilreisende predi-
kanter gjestet forsamlingen. Det lå også et særlig ansvar på kvinnene for å
vise omtanke for mennesker som trengte støtte i en vanskelig livssituasjon.22 Gjennom de mange håndarbeidsforeningene de dannet på lokalt nivå Gjennom de mange håndarbeidsforeningene de dannet på lokalt nivå
– kjent som kvinnemisjonsforeninger – drev de salg og utlodning av egen-
produserte søm- og strikkevarer. Slik klarte de å skaffe en hoveddel av inn-
tektsgrunnlaget for misjonsorganisasjonene.23 Disse kvinneforeningene
kunne ha tilknytning til en bestemt misjonsorganisasjon, men ofte ser vi at
de ønsket å dele midlene de skaffet mellom flere formål og organisasjoner.24 – kjent som kvinnemisjonsforeninger – drev de salg og utlodning av egen-
produserte søm- og strikkevarer. Slik klarte de å skaffe en hoveddel av inn-
tektsgrunnlaget for misjonsorganisasjonene.23 Disse kvinneforeningene
kunne ha tilknytning til en bestemt misjonsorganisasjon, men ofte ser vi at
de ønsket å dele midlene de skaffet mellom flere formål og organisasjoner.24 Kvinneforening i Våge, Spangereid. Fotograf ukjent, sannsynlig datering 1907. Foto: Lindesnes Bygdemuseum/Agderbilder.no Kvinneforening i Våge, Spangereid. Fotograf ukjent, sannsynlig datering 1907. Foto: Lindesnes Bygdemuseum/Agderbilder.no 178 konservative holdninger til likestilling på sørlandet Det er slik vi kjenner den tradisjonelle misjonskvinnerollen: praktisk tje-
neste i underordnede posisjoner. Men når vi ensidig fokuserer på bede-
husregimet, glemmer vi lett at den kristelige kulturen lenge samsvarte
med storsamfunnets allmenne kjønnsrollepraksis. En utbredt motvilje
mot å la kvinner tre fram i offentligheten ble ganske selvfølgelig overført
til de frivillige organisasjonenes arenaer, der talerstol og lederskap uten
videre ble sett som mannens domene.25 Så fikk nok budet om at kvinner
skulle «tie i forsamlingen» sterkere vekt på bedehuset, der slike normer
fortsatt ble sett som del av en gudgitt orden. Det er likevel verd å nevne at Det Norske Misjonsselskap (NMS) alt i
1904 ga kvinnene stemme- og representasjonsrett – ni år før norske kvin-
ner fullt ut ble tilkjent statsborgerlig stemmerett. På den annen side kan
en vise til avholdsrørsla, som også var en bevegelse med sterk oppslutning
blant kvinner. 25
Hagemann 1999
26
Fuglum 1972: 116 ff., 324
27
Predelli 1998 25
Hagemann 1999f 28
En sentral kilde er bokserien Kristenliv, utgitt av Norsk luthersk Misjonssamband (NLM) i peri-
oden 1948–1965 (Bergen: Lunde & Co.). Hver bok dekker en eller flere av NLMs kretser. Selv om
forfatterne hevder de har hatt et ønske om å formidle overlevert tradisjonen i lekmannsbeve-
gelsen på tvers av organisatoriske grenser, ligger tyngdepunktet i NLMs miljøer.
29
Wertsch 2002
30
Seland 2009
31
Se Predelli 1998; Tjelle 1999 Den tradisjonelle misjonskvinnerollen Her åpnet Det Norske Totalavholdsselskap (DNT) allerede
på 1880-tallet åpnet for full likestilling, både når det gjaldt stemmerett og
valgbarhet.26 Hang til bokstavtro bibeltolking er nok en viktig grunn til
at misjonsorganisasjonene sakket akterut på dette feltet. Ute på misjonsmarkene ble forbudet mot at kvinner fikk drive forkyn-
nelse utfordret, og pragmatiske hensyn kunne tvinge organisasjonenes
lederskap til å gå med på kompromisser.27 Over tid ser vi en viss opp
myking også i den hjemlige virksomheten. Men det tradisjonelle sam-
funnets komplementære oppfatning av manns- og kvinnerollen står ennå
sterkt i organisasjonenes interne arbeidsdeling, og prinsippet om kvin-
nens underordning under mannen er videreført langt opp mot vår egen
tid. Etter hvert som allmenne moderniserinsgprosesser utfordret denne
tenkemåten, måtte den kristelige kulturen i stadig sterkere grad framstå
som en forskansning av foreldede rollemønstre. Sett i tilbakeblikk kan en spørre hvordan bedehusets kvinner kunne
avfinne seg med et kjønnsregime som så sterkt markerte seg som avvik
fra samfunnsutviklingen for øvrig. Hvordan formet de sine virkefelt? Var
de faktiske grensene for handling og utfoldelse videre enn det vi i første
omgang forestiller oss? 179 kapittel 8 28
En sentral kilde er bokserien Kristenliv, utgitt av Norsk luthersk Misjonssamband (NLM) i peri-
oden 1948–1965 (Bergen: Lunde & Co.). Hver bok dekker en eller flere av NLMs kretser. Selv om
forfatterne hevder de har hatt et ønske om å formidle overlevert tradisjonen i lekmannsbeve-
gelsen på tvers av organisatoriske grenser, ligger tyngdepunktet i NLMs miljøer.
29
Wertsch 2002 Myndige religiøse kvinneroller I misjonsorganisasjonenes arkiver er kvinnene nesten usynlige – unn
taket er regnskapsbøkene, der håndarbeidsforeningene ruver i listene
over innkomne bidrag. Men bedehusets historieforvaltere har også samlet et rikt tradisjons-
materiale som gir innblikk i lokalt foreningsliv bak de formelle organisa-
sjonsstrukturene.28 Når dette stoffet formidles i bøker og tidsskrift utgitt
på misjonsbevegelsens egne forlag, bærer framstillingen naturlig nok
preg av behovet for å forme et kollektivt minne som – slik sosialantropo-
logen James Wertsch uttrykker det – kan skape en tjenlig fortid (a usable
past).29 Lest med kildekritisk distanse kan dette materialet like fullt gi
verdifull innsikt, ikke minst om kvinnenes handlingsrom på lokalt nivå. For her finner vi mange fortellinger om navngitte kvinner som – nesten
til overmål – skulle hylles og hedres. Med bakgrunn i denne typen minnemateriale har jeg i en tidligere
studie skissert tre idealtypiske posisjoner misjonsbevegelsens kvinner
kunne innta.30 Den tradisjonelle misjonskvinnerollen har vi alt vært inne
på. Den var knyttet til håndarbeidforeningene og til støtte for virksom-
heten på det lokale bedehuset. Dette var den mest alminnelige kristelige
kvinnerollen. Men etter hvert kan vi også identifisere et mindre gruppe
som fylte formelle eliteposisjoner. Det dreier seg dels om kvinner som
skulle støtte mannlige misjonærer i utetjeneste, dels om lønnede verv i
organisasjonenes hjemlige virksomhet. Da gjaldt det gjerne diakonalt
arbeid eller sekretærtjeneste rettet mot kvinneforeninger og barnelag.31 I tillegg møter vi en liten, men markant gruppe jeg plasserer i kate-
gorien uformelle eliteposisjoner. Det dreier seg om kvinner som på ulike
måter har vært framtredende i sine lokalsamfunn, selv om virksomheten
de drev ikke var legitimert gjennom formaliserte verv. Uten å markere 180 konservative holdninger til likestilling på sørlandet seg som opposisjonelle har disse kvinnene skaffet seg et større handlings-
rom enn hva bedehusets normer skulle tilsi. De kunne tillate seg å stille
kritiske spørsmål til mannlige ledere; de djerveste kunne sågar utfordre
både prest og predikant i teologiske spørsmål. En sjelden gang finner vi
også fortellinger om kvinner som på visse vilkår har fått aksept for å opp-
tre som predikanter. t Det var helst ugifte kvinner som inntok slike uformelle eliteposisjoner. Fristilt fra arbeid og omsorg i en familie hadde de selvsagt større mulig-
heter til å velge andre livsoppgaver, og til å vinne sosial aksept for sine
valg. Ofte drev de sin kristelige tjeneste med bakgrunn i et yrke som ga
dem brede kontaktflater. Myndige religiøse kvinneroller Det kunne for eksempel være kvinner som liv-
nærte seg ved søm. Om de drev egen systue eller flyttet rundt til kunder i
private hjem, kunne de kombinere praktisk arbeid med sosial omgang og
målbevisst religiøs påvirkning. I andre tilfeller kunne det være arbeids-
plass i en landhandel eller på et meieri som var basis. tt Både gifte og ugifte kvinner kunne gå inn i selvpålagt diakonal tje-
neste. Ved å ta på seg pleie av gamle og syke, og ved å støtte familier og
enkeltmennesker som av ulike grunner slet tyngre enn andre, kunne de
over tid opparbeide velvilje og respekt for sin gjerning. Noen av disse fikk
en nesten opphøyd posisjon i sine lokalsamfunn. Filantropisk innsats
kombinert med en form for privat sjelesorg ser ut til å være et kjennetegn
ved virksomheten disse kvinnene drev. I bedehuskulturens fortellinger finner vi ikke sjelden omtale av «bønne
kvinner» – en benevnelse man brukte om kvinner man mente hadde sær-
lige evner til å få Gud i tale. En kunne ha et forsterket håp om bønnesvar
når disse kvinnene ba for syke, ba om god grøde i landbruket eller om
beskyttelse for mennene som var ute på havet. En god bønnekvinne ville
også be om at de «verdslige», de som ikke hørte til bedehusflokken, måtte
bli ledet til omvendelse og ‘rett tro’. Bønnekvinnene kunne dessuten nyte
generell tillit som rådgivere; ofte var de anerkjent som særlig dyktige også
i praktisk arbeid. Bedehusets tradisjonsformidling gir altså rom for en rekke fortellinger
om selvstendige og sterkt motiverte kvinner som har forvaltet betydelig
religiøs makt. Uten å opponere åpent, opptrådte de på flere vis grense
overskridende innenfor et regime som forfektet kvinnens underordning 181 kapittel 8 under mannen. Ettersom de ikke hadde formelle verv, er det knapt spor
etter dem i organisasjonenes arkiver. Men bildene som tegnes, viser at
myndige kvinneroller på visse vilkår ble idealisert i den kristelige kultu-
rens kollektive minne. 32
Molland 1961: 186 ff.
33
Molland 1961: 194–195
34
Molland 1961: 197–198
35
Slettan 1986: 140 Status og selvbevissthet legitimert ved tro Vi som i dag søker innsikt i 1800- og 1900-tallets kristelige kultur, har
nok begrensede forutsetninger for å forstå hva troen kunne bety for den
enkelte og for opplevelsen av fellesskap i disse miljøene. I pietismens uni-
vers var jordelivet ensidig sett som en «prøvelsens tid»; håpet lå i en tro
som kunne bære videre til et salig etterliv. Foruten den grunnleggende
læren om tro som adgang til frelse, var den lutherske kallsetikken og
tesen om det «allmenne prestedømmet» sterke pilarer i bedehusets teo-
logi.32 Dette var viktig tankemateriale også for kvinnenes fortolkning av
sine livskår. Kallstanken forutsetter at hvert menneske er kalt av Gud til å virke i
verden. For noen kunne det dreie seg om en spesiell innsats, men for de
fleste handlet det om å reise en himmel over det jevne, strevsomme livet
de var henvist til å leve.33 Her var det inspirasjon å hente både for det store
flertallet av tradisjonelle misjonskvinner og for de få som tok mål av seg
til å entre eliteposisjoner. Tesen om det allmenne prestedømmet hevder at
den troende direkte og uten noe geistlig mellomledd kan søke Guds ord
og bringe sin innsikt videre.34 Med bakgrunn i denne læren kunne både
menn og kvinner i lekmannsbevegelsen se seg berettiget til å utfordre
presteskapets autoritet. Både fra kirkens prekestol og i bedehusets forkynnelse kunne kvin-
ner bli framhevet som edlere skapninger enn menn. Slike budskap kom
ikke minst til uttrykk når misjonsbevegelsens kvinneforeninger skulle
hylles for flid og utholdenhet.35 Men ikke alle kvinner føyde seg like lett
etter tradisjonelle skjema for arbeidsdeling. Sosiologen Line N. Predelli 182 konservative holdninger til likestilling på sørlandet har gjennomført en studie av kvinnelige og mannlige medarbeidere i tje-
neste for NMS i tidsrommet ca. 1870–1910. Studien, som omfatter både
hjemme- og utetjenesten, viser et sammensatt bilde. Særlig på fremmed
misjonsmark kunne organisasjonsledelsens kjønnsregulerte instrukser
oppleves som et hinder i møtet med lokal kultur. Når praktisk erfaring
på visse områder støtte an mot dette regimet, kunne ledelsen se seg nødt
til å godta – eller i alle fall se gjennom fingrene med – at kvinner flyttet
grenser. I andre tilfeller kunne det komme til harde konfrontasjoner.36 At misjonærer i utetjeneste brakte slike erfaringer til hjemlandet, har
nok over tid virket inn på organisasjonenes holdninger i kjønnsrelaterte
spørsmål. Status og selvbevissthet legitimert ved tro Bedehuset var jo heller ikke upåvirket av storsamfunnets
utvikling, der lovverket utover på 1900-tallet suksessivt åpnet for økt
likestilling mellom kvinner og menn. I denne perioden ble også misjons-
organisasjonenes virksomhet sterkere forgreinet; organisasjonsbyråkra-
tiet vokste og ledelsen så seg i økende grad tjent med å engasjere kvinner
til tjenester av den typen jeg tidligere har beskrevet som ramme rundt
kvinner i formelle eliteposisjoner. 36
Predelli 1998 Hva er det med Agder? Innenfor den langstrakte kyststripen som utgjør det norske bibelbeltet,
vil det naturlig nok være skiftninger og variasjon vi ikke ser på grovteg-
nede kulturkart. Er det mulig å peke på trekk ved Agder som kan forklare
at landsdelen peker seg ut som særlig konservativ i likestillingsspørsmål? En anekdotisk fortelling går ut på at Gabriel Øidne etter et foredrag
om det sør- og vestlandske bibelbeltet fikk spørsmål om hva som lå til
grunn for det særegne ved denne kulturregionen. Øidne skal ha tenkt seg
om så lenge at forventningene steg i salen: Var det nå man skulle få den
altomfattende forklaringen? Da foredragsholderen endelig svarte, kom
det kort: «Nei, dette er heilt uforklarleg!». Fortellingen poengterer den
solide empirismen som kjennemerker Øidnes arbeid. Svaret hans – om
det faktisk var dette han sa – må vi se som en humoristisk påminning
om det komplekse og mangetydige som ligger i ethvert begrep om kultur. Innenfor den langstrakte kyststripen som utgjør det norske bibelbeltet,
vil det naturlig nok være skiftninger og variasjon vi ikke ser på grovteg-
nede kulturkart. Er det mulig å peke på trekk ved Agder som kan forklare
at landsdelen peker seg ut som særlig konservativ i likestillingsspørsmål? En anekdotisk fortelling går ut på at Gabriel Øidne etter et foredrag
om det sør- og vestlandske bibelbeltet fikk spørsmål om hva som lå til
grunn for det særegne ved denne kulturregionen. Øidne skal ha tenkt seg
om så lenge at forventningene steg i salen: Var det nå man skulle få den
altomfattende forklaringen? Da foredragsholderen endelig svarte, kom
det kort: «Nei, dette er heilt uforklarleg!». Fortellingen poengterer den
solide empirismen som kjennemerker Øidnes arbeid. Svaret hans – om
det faktisk var dette han sa – må vi se som en humoristisk påminning
om det komplekse og mangetydige som ligger i ethvert begrep om kultur. 183 kapittel 8 Tilbake til spørsmålet om hvorfor nettopp Agder utmerker seg ved kon-
servatisme i likestillingsspørsmål – En kunne være fristet til å svare som
Øidne. Men jeg skal våge meg et steg videre, og peke på noen topografiske
og samfunnsgeografiske strukturer som kan ha ligget til rette for en mer
slitesterk kristenkonservatisme på Sørlandet enn det vi ser i øvrige deler
av bibelbeltet. Før vi går nærmere inn på disse aspektene, må vi knytte an
til det vi kan se som fellestrekk ved Øidnes «mørke kyststripe». 37
Seland 2006: 369 ff., 392 ff.; Try 1986
38
Seland 2020 37
Seland 2006: 369 ff., 392 ff.; Try 1986 38
Seland 2020 Hva er det med Agder? Agder speiler ikke så klart det skarpe kulturskillet som Øidne fram-
hever mellom ytre og indre bygder på Vestlandet (se ovenfor). Selv om
pietisme og bedehuskultur også i agderfylkene fikk sterkest gjennomslag
langs kysten, ble foreningslivet her mer variert enn det vi ser i vestlandske
kyststrøk. Heiebygdene på Agder har også et mer bredspektret forenings-
liv enn det Øidne finner i de indre fjordbygdene på Vestlandet. I indre
deler av Agder har det vært mer av jevnbyrdig konkurranse mellom reli-
giøs og frilynt foreningskultur. Dette må vi se i sammenheng med at selve
assosiasjonsfenomenet – tilbøyeligheten til å danne frivillige foreninger
for ulike formål – ganske seint fikk gjennomslag i disse områdene. Her
vant lekmannsrørsla for alvor fram samtidig som den frilynte rørsla var
på frammarsj.37 Øidne går i liten grad inn på mulige årsaker til det kulturgeografiske
mønsteret han dokumenterer. Han tar som utgangspunkt at de to kultur
regionene han kartlegger – «Den mørke kyststripa» og «Fjell- og fjord-
Noreg» – begge representerer periferiens motkulturer i opposisjon til en
dominerende sentrumskultur. Når det gjelder den sør- og vestlandske kyst-
kulturen, som vi her har valgt å kalle bibelbeltet, gir han likevel tydelige
hint om en sammenheng med næringsstrukturelle forhold. Han legger til
grunn at jevnbyrdighet i det økonomiske disponerer for samstemmighet i
ideologisk orientering, og dermed for enhetlig kultur. Dette er en tolkning
som har bred støtte – eller som ofte tas for gitt – både i samfunnsfaglig og
historiefaglig litteratur.38 I det historiske bildet er materiell egalitet et klart kjennetegn ved
bygdeøkonomien i kyststrøkene på Agder. Her var ressursene stort sett 184 konservative holdninger til likestilling på sørlandet delt på små gårdparter, og det var knapt noen grobunn for klassekonflikt. Vi skal likevel merke oss visse variasjoner fra øst til vest i landsdelen. Mens nasjonal statistikk viser at Vest-Agder rundt 1870 var det fylket som
hadde mest utpreget småbruksstruktur, var ressursfordelingen i land-
bruket mer sammensatt i bygdene lenger øst. Forskjellene er likevel ikke
større enn at Aust-Agder hadde om lag samme fordeling mellom små,
mellomstore og større bruk som vestlandsfylket Hordaland.39 Når det gjelder egalitet i landbruket, faller Agder altså pent inn i Øidnes
klassifisering. Men det er andre sider ved økonomisk struktur som Øidne
ikke berører. Ser vi etter det særegne ved Agder, er bytettheten et iøyne
fallende trekk. Rogaland og Hordaland har sine urbane tyngdepunkt
i Stavanger og Bergen. 40
Abrahamsen 2013; Knudsen 2002; Slettan 1998: 49 ff. 39
Slettan 1998: 46–47 41
Knudsen 2002: 32 41
Knudsen 2002: 32 39
Slettan 1998: 46–47f Hva er det med Agder? Foruten Arendal og Kristiansand gir den lange
rekken av småbyer langs Sørlandskysten en særegen samfunnsgeografisk
struktur som skiller seg ut også innenfor det sør- og vestlandske kyst-
beltet. Mellom byene finner vi dessuten en rekke strandsteder og uthav-
ner med trekk av småbysamfunn.40 Geografen Jon P. Knudsen gir dette
oversiktsbildet: Det er de klassiske kystbyene … beliggende i to til tre mils avstand fra hver-
andre, med et lokalt omland av nært innland og skjærgård, et fjernere oppland
bestående av dalfører og heier innover landet og en global arena som knyttet
byene til det som var den viktigste næringsveien i disse byenes gullalder: han-
del og skipsfart.41 Her er vi ved kjernen av det som særmerker Agder: rekken av småbyer
langs kysten, den topografiske strukturen som styrker tilknytningen
mellom innland og kyst, den tette oversjøiske kontakten. Det her vi må
se etter forklaringer på at den folkelige pietismen som gjennom genera-
sjoner har preget hele bibelbeltet, fikk sterkere støttepunkt og mer varig
innvirkning nettopp i denne landsdelen. 185 kapittel 8 Strukturelle vilkår for kulturspredning Den sterke veksten i norsk lekmannsrørsle kom i kjølvannet av tre omfat-
tende vekkelsesbølger. Den første kan tidfestes til 1870-tallet, den andre
og mest omfattende bølgen kom rundt år 1900, den tredje i mellomkrigs-
tiden.42 Det er verd å merke seg at de første av disse bølgene i tid faller
sammen med de mest hektiske fasene i emigrasjonshistorien. Utvandring
og vekkelse kan ses om samtidige følger av dype sosiale endringsproses-
ser. Men det er også klart at mye av indremisjonens framgang var inspi-
rert av transatlantisk kulturkontakt.43 42
Seland & Aagedal 2008: 37 ff.
43
Seland 2013, 2020
44
Seland 2006: 284, 290
45
Slettan 1998: 28 ff.
46
Knudsen 1986 Kontakten med USA Som vi alt har vært inne på, representerte den angloamerikanske nyevan-
gelismen en vekkelseskristendom som både i budskap og form siktet mot
å framvirke masseomvendelse. Sjøfart og emigrasjon la til rette for at sør-
og vestlendinger ble eksponert for amerikansk revivalism i langt større
grad enn nordmenn flest. At mange predikanter fra Sør- og Vestlandet
selv reiste over Atlanteren for å lære, sier også sitt om spredningspotensia
let for amerikanisert vekkelseskristendom i Norge.44 Vi skal også merke
oss at Agder hadde en høy andel utvandrere i forhold til folketallet, et
høyt antall tilbakevendte emigranter og utbredt «Amerika-pendling»
gjennom store deler av 1900-tallet.45 Her ligger nok mye av grunnlaget
for styrken som ennå manifesterer seg i sørlandsk kristenkonservatisme. Øidnes kulturgeografiske kart profilerer regionale motsetninger i et
større bilde; de viser ikke variasjoner på lavere nivå. I vår sammenheng
kunne vi hatt nytte av studier som avdekker variasjon langs sentrum–
periferi-dimensjonen på region- og distriktsnivå. Anvendt på Øidnes
kart ville slike utdypninger uten tvil vist betydelige skiftninger i kultur
innenfor den langstrakte kyststripen som inngår i bibelbeltet, og byenes
rolle som sentra for kulturspredning ville tre tydeligere fram.46 186 konservative holdninger til likestilling på sørlandet 47
Knudsen 1986 48
Handeland 1948, passim, sitat: 62 49
Slettan 1998: 91 49
Slettan 1998: 91 Sørlandsbyene som religiøse sentra Internasjonale studier viser en sterk sammenheng mellom urbanisering
og økende sekularisering i vestlige land. I større byer, der næringsliv og
befolkning er mer mangfoldig enn i distriktene rundt, vil også ideologisk
og religiøs orientering være mer pluralistisk. I kommunikasjon mellom
by og omland vil dette forholdet i seg selv styrke sekularisering. Når det
gjelder mindre byer, er bildet mer sammensatt. Der det er sterke religiøse
miljøer i byen, og en viss ideologisk samforstand mellom disse miljøene
og omgivende distrikt, vil byen i mindre grad bidra til sekularisering.47 Trekker vi denne tendensen litt videre, er det ikke urimelig å tenke
seg at små byer med tilsvarende kulturelle bånd til distriktene sågar blir
aktive spredningssentra for religiøst engasjement. Når det gjelder Agder,
ligger det nært å vise til Mandal som kjerneområde for indremisjon og
bedehuskultur i det gamle vestfylket. Her ble det tidlig etablert en tradi-
sjon for et årvisst stevne som «samla dei truande frå Lindesnes og heilt
opp til Åseral og Eiken» rundt første helga i januar.48 Tradisjonen for slike
«helligtrekongermøter» ble holdt i hevd gjennom generasjoner. Histo
rikeren Bjørn Slettan gir dette tidsbildet fra 1870-tallet: I Mandal hadde dei «helligtrekongermøter» kvar 6. januar. […] Det var guds
teneste, men samstundes marknadsdag og folkefest. Dei kom frå bygdene vidt
omkring, så det var vanskar med å få inn hestar og folk for natta. Motiva for
å samlast kunne vere så ymse; butikkane og skjenkestadene hadde òg godt
besøk. Men det var likevel det kristelege innhaldet som var sentrum i det
heile. Den store kyrkja i byen kunne romme over 1800 menneske, men denne
dagen var det ikkje ståplass ledig.49 Oversjøisk kulturkontakt inspirerte også til tidlig etablering av frikirke
lighet. Som tidligere nevnt kom frikirkene alt i alt til å stå tallmessig svakt
i Norge. Men Aust-Agder skiller seg alt tidlig på 1900-tallet ut med en 187 kapittel 8 oppslutning langt over gjennomsnitt for riket. Her trer Arendal fram
som sentrum for frikirkelige bevegelser.50 50
Knudsen 1994: 145 ff., 160 ff.; Slettan 1998: 313
51
Gundersen 1996; Seland 2006: 221 ff., 255 ff.
52
Seland 2006: 240–241, 401 ff. 50
Knudsen 1994: 145 ff., 160 ff.; Slettan 1998: 313ff ff
51
Gundersen 1996; Seland 2006: 221 ff., 255 ff.f Styrke i organisering og tilpasning over tid Så langt kan vi altså peke på historisk utvikling knyttet til oversjøisk
kontakt og byenes rolle i religiøs kulturspredning som bakgrunn for sør-
landsk kristenkonservatisme. På et annet plan må vi framheve evnen til
omstilling i det kristelige lekfolkets organisasjoner. Om verdigrunnlaget
var konservativt, var lekmannsrørsla lenge i fremste linje når det gjelder
moderne organisasjonsbygging.51 Etter hvert som organisasjonene vokste i styrke, ble det også utviklet
helhetlige rammer for sosial og kulturell identitet. ’Barn av bedehuset’ fikk
opplæring i søndagsskole og barnelag før de gikk inn i en ungdomsfore-
ning, og kanskje søkte seg inn på en kristelig ungdomsskole. Som voksne
orienterte de seg i verden gjennom kristelige blader og aviser, med skjønn-
litteratur fra kristelige forlag som avveksling og tidtrøyte. I byene kunne
en møtes på misjonskaféer og overnatte på misjonshotell. Sommerleire og
familiestevner bygde opp under et videre fellesskap på regionalt og nasjo-
nalt nivå. Slik ble nye generasjoner sosialisert inn i stabile miljøer, for i sin
tur å bidra til å forme og omforme en tidstilpasset kristelig kultur.52 Som historiker kan jeg bidra til å skape dypere forståelse for kultur
utvikling over tid, men jeg har begrensede forutsetninger for å forklare
bakgrunnen for dagens kristenkonservatisme. Når jeg nå skal trekke trå-
der opp mot vår egen tid, må det bli i form av spørsmål og antydninger. Da vil jeg først rette oppmerksomheten mot noen momenter i de sam-
funnsfaglige studiene vi kan se som tidstilpassede uttrykk for tendenser
vi kjenner fra tradisjonell kristelig kultur. Ett moment som innbyr til kommentar, er inntrykket av at en konser-
vativ minoritet synes å ha en moralsk autoritet når det gjelder sørlendinge-
nes syn på likestilling. Dag Ellingsen og Ulla-Britt Lilleaas minner om at de 188 konservative holdninger til likestilling på sørlandet konservative alt i alt er i mindretall, også på Sørlandet, men at det like fullt
synes som om disse får prege regionens identitet i større grad enn «antall
og andel skulle tilsi».53 Her ligger det nært å peke på en parallell i den ‘klas-
siske’ bedehuskulturen, i det jeg har omtalt som minoritetens ideologiske
hegemoni: Om antallet som jevnlig var aktive i religiøse foreninger aldri var
høyt, hadde den pietistiske vekkelseskristendommen likevel et så sterkt grep
om folk at denne trosforståelsen kom til å prege det allmenne normverket. 54
Ellingsen & Lilleaas 2010; Magnussen et al. 2012; Magnussen & Repstad 2010 53
Ellingsen & Lilleaas 2010, sitat: 95 55
Magnussen & Repstad 2012 53
Ellingsen & Lilleaas 2010, sitat: 95 56
Magnussen & Repstad 2010; Woodhead 2007. Se også Magnussens kapittel i denne antologien.
57
Woodhead 2007
58
Bloch-Hoell 1973 Styrke i organisering og tilpasning over tid konservative alt i alt er i mindretall, også på Sørlandet, men at det like fullt
synes som om disse får prege regionens identitet i større grad enn «antall
og andel skulle tilsi».53 Her ligger det nært å peke på en parallell i den ‘klas-
siske’ bedehuskulturen, i det jeg har omtalt som minoritetens ideologiske
hegemoni: Om antallet som jevnlig var aktive i religiøse foreninger aldri var
høyt, hadde den pietistiske vekkelseskristendommen likevel et så sterkt grep
om folk at denne trosforståelsen kom til å prege det allmenne normverket. Videre vil jeg reflektere rundt funn som viser mer utbredt likestillings-
konservatisme i frikirkelige samfunn enn i statskirketilknyttede mil
jøer.54 Her må vi vel også være oppmerksom på at kategorien statskirkelige
miljøer, som de aktuelle studiene viser til, nok er mer sammensatt enn en
først tenker seg. Denne kategorien omfatter både den lavkirkelige bede-
huskulturen, med sin orientering mot bokstavtro bibeltolkning, og mer
kulturåpne, folkekirkelige miljøer. Om det statistiske materialet hadde
gitt mulighet til å skille ut lavkirkelige miljøer, ville forskjellen mellom
disse og den frikirkelige kategorien kanskje ikke vært så stor? Om det likevel holder stikk at de frikirkelige utmerker seg ved konser-
vatisme, er det naturlig å peke på den generelle bakgrunnen Agder har,
med tidlig etablering og forholdvis sterk utbredelse av frikirkelighet. Her
kan en også legge til at oppslutningen om frikirkesamfunn i seinere tid
har økt betydelig i denne landsdelen, også i områder som omfattes av det
gamle Vest-Agder fylke.55 Den som ser seg litt rundt på Sørlandet, vil
nok også få et inntrykk av at flere frikirkemiljøer har lykkes godt med
tiltak og aktivitetsformer som appellerer til barn og unge, og at de skaper
attraktive sosiale arenaer ikke minst for barnefamilier. Det er rimelig å
tenke seg at dette er en profil som fører til nyrekruttering nettopp blant
ungdom og unge voksne. Om det faktisk er slik at de mest framgangsrike frikirkemiljøene særlig
rekrutterer fra yngre alderssegmenter, er dette en tendens det er interes-
sant å holde opp mot den tendensen som Ellingsen og Lilleaas avdekker
i sin studie fra 2010: At unge sørlendinger ser ut til å være mer «like
stillingstradisjonelle» enn sine jevnaldrende i resten av landet. 189 kapittel 8 Konservative kjønnsregimer i moderne kontekst Vårt blikk på den klassiske bedehuskulturens kjønnsregime viste et mer
mangfoldig spekter av kvinneroller enn det vi forbinder med den tra-
disjonelle misjonskvinnerollen. Også her var det plass til kvinner som
ønsket et utvidet handlingsrom. Det krevde nok sitt av personlig styrke
og sosiale evner; men så lenge disse kvinnene ikke utfordret det formelle
regimet, ble de møtt med velvilje og respekt. Fram til langt ut på 1900-tal-
let var det jo heller ikke noe påtakelig press verken på bedehuset eller i det
allmenne samfunnet fra kvinner som strakte seg etter formelle verv. Her
var det 1970-tallets «nyfeminisme» som skapte vannskillet. Etter hvert som religiøse begrunnelser for kvinners underordning har
tapt legitimitet i vestlige land, er det naturlig å spørre hvorfor kvinner fort-
satt velger å slutte seg til eller bli værende i kristne miljøer som begren-
ser deres handlingsrom. Det fins ennå sekter der det kan stå om aksept
for prevensjon. Men langt oftere ser vi at også kristenkonservative miljøer
langsomt tilpasser sitt normverk til storsamfunnets standard når det gjel-
der både manns- og kvinneroller. Abortspørsmålet, homofilt samliv og nye
muligheter for bioteknologiske inngrep er fortsatt omstridt. Men ellers kan
vi konstatere at liberaliserte holdninger vinner fram når det gjelder arbeids-
deling i hjemmet og kvinners adgang til utdannelse og lønnet arbeid.56 Gitt den historiske kontakten mellom amerikanske og norske
vekkelsesmiljøer, er det fristende å spekulere over betydningen av slike
forbindelser i dag. Religionssosiologiske studier viser at uvilje mot å til-
passe seg et liberalt syn på kjønnsmessig likestilling er en sentral faktor
i den kristenkonservative bevegelsen i dagens USA.57 Vi vet også at ame-
rikansk innflytelse har vært særlig sterk i frikirkelige miljøer.58 Om det
fortsatt er bærekraft i båndene mellom norske frikirker og amerikanske
søstersamfunn, ville det være naturlig å spørre om også dette har vært
med på å prege sørlendingenes holdninger til likestilling i konservativ lei. Religionssosiologer som studerer konservative forsamlinger i dagens
USA, skiller mellom ulike former for tilpasning og motivasjon blant 190 konservative holdninger til likestilling på sørlandet kvinner som er underlagt tradisjonelle kjønnsregimer. Mens man i
enkelte forsamlinger uten videre innordner seg det normverket som gjel-
der, ser en at kvinner i andre miljøer aktivt utvider sitt eget handlings-
rom. Det betyr ikke at de utfordrer det hierarkiske hovedmønsteret som
krever underordning under mannen. Det betyr heller ikke at de vegrer
seg for de typiske kvinneoppgavene de er tildelt innenfor fellesskapet. 59
Woodhead 2007
60
Woodhead 2007
61
Se f. eks. Vestly 2011, 2013. (Vestly er i inneværende valgperiode representant for Partiet De
Kristne (PDK) i Kristiansand bystyre og i Agder fylkesting.) 60
Woodhead 2007 Konservative kjønnsregimer i moderne kontekst De stiller også tallsterkt og lojalt på den felles søndagsgudstjenesten som
ledes av en mannlig pastor. Men på ukedager kan de samles til egne kvin-
nemøter, som på sett og vis fungerer som en parallell organisasjon.59 Den formelle begrunnelsen for disse sammenkomstene kan gjerne
være bibelstudier. Men det som betyr mest for deltakerne i slike ‘kvinne
menigheter’, er tilgangen til en sosial arena som byr på meningsfulle
samvær, og som blir ramme for et fellesskap preget av gjensidig støtte og
sympati. Her deler kvinnene erfaringer og drøfter problemer knyttet til
familieansvar, barneoppdragelse, ekteskapelig samliv, helse, arbeidsplass
og alt en ellers står oppe i av dagliglivets utfordringer.60 Slike kvinnefellesskap er til nå lite undersøkt i norsk kontekst. Men vi
vet jo at de fins, og at de er viktige for kvinner, både i konservative og mer
liberale religiøse forsamlinger. De som søker denne typen fellesskap, vil
i varierende grad være åpne for storsamfunnets ideelle likestillingskrav,
men det er grunn til å tro at de jevnt over har en grunnholdning som
pålegger kvinner et særlig ansvar for hjem og familie. I nyere tid ser vi også at slike holdninger koples til en mer allmenn
samfunnsdebatt, der det reises kritikk mot økende effektivitetskrav i
arbeidslivet, familier i «tidsklemme» og institusjonalisering av barns
oppvekst.61 Da er det kort vei til holdningene Ellingsen og Lilleaas avdek-
ker i sin studie fra 2010: Et tradisjonelt kjønnsrollemønster på Sørlan-
det kan legitimeres ved ønsket om «det gode liv» – et liv der en finner
ønsket balanse mellom arbeid og fritid, og der en prioriterer familieliv og
omsorg for barn. 191 kapittel 8 Sluttord Utgangspunktet for dette kapitlet er samfunnsfaglige studier som viser at
Agder ligger på bunnplass i alle målinger som gjelder likestilling mellom
kjønn i Norge. Ettersom en ikke kan peke på spesielle årsaker knyttet til
økonomiske og næringsstrukturelle forhold, stiller samfunnsforskerne
spørsmål om en mulig sammenheng med landsdelens pietistiske kultur-
arv. Som historiker ser jeg dette spørsmålet som invitasjon til en ganske
krevende dyst. Det sier seg selv at kulturell innflytelse aldri fullt ut kan kartlegges. Skal vi i det hele tatt forsøke å finne forklaringer på dagens konserva-
tisme, må det være i form av utprøvende refleksjon. Jeg har sett det som
viktig å minne om at Agder inngår i et mer omfattende sør- og vestlandsk
kystbelte, der religion i sterkere grad enn i landet for øvrig har preget
kultur og samfunnsliv. Videre har jeg trukket noen linjer gjennom den
folkelige pietismens historie i Norge, med særlig vekt på innflytelsen
fra angloamerikansk vekkelseskristendom. Som bakgrunn for spørs-
mål knyttet til likestillingsproblematikk, har jeg skissert et bilde av det
tradisjonelle bedehusets kjønnsregime. Her modellerer jeg den typiske
misjonskvinnerollen, men viser også at bedehusets kvinner kunne for-
valte betydelig uformell makt. Når det gjelder angloamerikansk innflytelse har jeg pekt på grunn-
leggende strukturelle vilkår som la til rette for særlig tett kulturkontakt
mellom Sørlandet og USA. Med blikk for kulturspredning innenfor
landsdelen, har jeg framhevet samfunnsgeografiske betingelser knyttet
til den tette rekken av småbyer som kjennetegner sørlandskysten. Gjen-
nom handel og skipsfart ga sørlandsbyene vide horisonter for oversjøisk
kulturkontakt, samtidig som de kystnære bygdene ble preget av bynær
beliggenhet. Tett kontakt med amerikansk revivalism ga ikke bare impulser til den
brede lavkirkeligheten, den inspirerte også til tidlig etablering av frikirke
lighet på Sørlandet. Religionssosiologiske studier viser for øvrig at visse
frikirker har hatt en betydelig vekst i nyere tid. Med bakgrunn i historiske
tendenser har jeg lagt vekt på spørsmålet om hvor sterkt amerikanske
impulser slår inn i dagens sørlandskultur. I denne sammenhengen har 192 konservative holdninger til likestilling på sørlandet jeg bl.a. vist til sosiologiske studier som avdekker en påtakelig motstand
mot kjønnsmessig likestilling blant kristenkonservative i USA. Så hvor langt kommer vi med spørsmålet om sammenheng mellom
pietisme og konservative holdninger til likestilling på Sørlandet? Om
kristendomsforståelsen er myknet i kantene og de allmenne sekularise-
ringsprosessene går sin gang, gir den religiøse kulturarven ennå en dyp
klangbunn for sørlendingenes livsvalg og verdisyn. Sluttord Ettersom sørlands
pietismen i så høy grad har hentet næring fra amerikanske vekkelses
miljøer, er det gode grunner for å følge dette sporet også i samtidsstudier
av holdninger til likestilling i denne landsdelen. Kilder og litteratur Abrahamsen, O. A. (2013). Byene på Agder i spennet mellom det hjemlige og det
fremmede. I B. E. Johnsen (Red.), Sørlandet og utlandet. Transnasjonal kontakt,
internasjonal påvirkning (s. 67–82). Cappelen Damm Høyskoleforlaget. https://doi.org/10.23865/noasp.79 Abrahamsen, O. A. (2013). Byene på Agder i spennet mellom det hjemlige og det
fremmede. I B. E. Johnsen (Red.), Sørlandet og utlandet. Transnasjonal kontakt,
internasjonal påvirkning (s. 67–82). Cappelen Damm Høyskoleforlaget. https://doi.org/10.23865/noasp.79 Bloch-Hoell, N. (1973). The impact in Norway of American religious dissent. I A. N. J. den Hollander (Red.), Contagious conflict. The impact of American
dissent on European life (214–232). Brill. Botvar, P. K. & Schmidt, U. (Red.). (2010). Religion i dagens Norge. Mellom
sekularisering og sakralisering. Universitetsforlaget. Botvar, P. K. & Schmidt, U. (Red.). (2010). Religion i dagens Norge. Mellom
sekularisering og sakralisering. Universitetsforlaget. Botvar, P. K., Repstad, P. & Aagedal, O. (2010). Regionaliseringen av norsk
religiøsitet. I P. K. Botvar & U. Schmidt (Red.), Religion i dagens Norge. Mellom
sekularisering og sakralisering (s. 44–59). Universitetsforlaget. Botvar, P. K., Repstad, P. & Aagedal, O. (2010). Regionaliseringen av norsk
religiøsitet. I P. K. Botvar & U. Schmidt (Red.), Religion i dagens Norge. Mellom
sekularisering og sakralisering (s. 44–59). Universitetsforlaget. Ellingsen, D. & Lilleaas, U.-B. (2010). Det gode liv på Sørlandet og tradisjonelle
kjønnsroller. Universitetet i Agder. http://hdl.handle.net/11250/135075 Fossåskaret, E. (2015). Arbeidarrørsla og bedehuset. I E. Larsen (Red.), Det mørke
fastland? Arbeiderbevegelsen i Rogaland (s. 12–55). Arbeidernes historielag. Fuglum, P. (1972). Kampen om alkoholen i Norge 1816–1904. Universitetsforlaget. Furre, B. (1987). Rogaland – noko for seg. Kven var oftedølene? I E. Fossåskaret &
B. Furre (Red.), Rogalandskulturen. Mellom religion og politikk. Ei tverrfagleg
vandring gjennom 120 år (s. 6–27). Høgskolesenteret i Rogaland. B. Furre (Red.), Rogalandskulturen. Mellom religion og politikk. Ei tverrfagleg
vandring gjennom 120 år (s. 6–27). Høgskolesenteret i Rogaland. Gundersen, K. T. (1996). Visjon og vekst. Framveksten av de frivillige kristelige
organisasjonene 1814–1940. Tidsskrift for Kirke, Religion og Samfunn, tilleggshefte
nr. 3. https://urn.nb.no/URN:NBN:no-nb_digibok_2008062004011 Gundersen, K. T. (1996). Visjon og vekst. Framveksten av de frivillige kristelige
organisasjonene 1814–1940. Tidsskrift for Kirke, Religion og Samfunn, tilleggshefte
nr. 3. https://urn.nb.no/URN:NBN:no-nb_digibok_2008062004011 Hagemann, G. (1999). De stummes leir? 1800–1900. I I. Blom & S. So
Med kjønnsperspektiv på norsk historie (s. 135–226). Cappelen. 193 kapittel 8 Handeland, O. (1948). Kristenliv på Agder. 50-årsskrift for Agder krins av Det norske
lutherske kinamisjonsforbund. Forbundets forlag. Johnsen, B. E. (Red.). (2013). Sørlandet og utlandet. Transnasjonal kontakt,
internasjonal påvirkning. Cappelen Damm Høyskoleforlaget. Kilder og litteratur https://doi.org/10.23865/noasp.79 Knudsen, J. P. (1986). Culture, power and periphery. The Christian lay movement
in Norway. Norsk Geografisk Tidsskrift – Norwegian Journal of Geography, 40(1),
1–14. https://doi.org/10.1080/00291958608552151i Knudsen, J. P. (1994). Kulturspredning i et strukturelt perspektiv. Eksemplifisert
ved politisk og religiøs endring under moderniseringen av det norske samfunn
[Doktorgradsavhandling]. Lund: Lund University Press. Knudsen, J. P. (2002). Makt i regional fasong. I J. P. Knudsen & H. Skjeie
(Red.), Hvitt stakitt og fiberoptikk: regionale myter – regional makt (s. 31–48). Høyskoleforlaget.i Knudsen, J. P. & Skjeie, H. (Red). (2002). Hvitt stakitt og fiberoptikk: regionale myter
– regional makt. Høyskoleforlaget. Magnussen, M. L. & Repstad, P. (2010). Religion og likestilling mellom menn og
kvinner. I P. K. Botvar & U. Schmidt (Red.), Religion i dagens Norge. Mellom
sekularisering og sakralisering (s. 149–165). Universitetsforlaget. Magnussen, M. L., Repstad, P. & Urstad, S. (2012). Skepsis til likestilling på Sørlandet
– et resultat av religion? Tidsskrift for kjønnsforskning, 36(3/4), 204–222. https://www.idunn.no/tfk/2012/03-04/skepsis_til_likestilling_p_srlandet_-_et_
resultat_av_rel Molland, E. (1961). Konfesjonskunnskap. Kristenhetens trosbekjennelser og
kirkesamfunn. Land og kirke. Norseth, K. (2007). «La oss bryte over tvert med vor stumhet!» Kvinners vei til
myndighet i de kristelige organisasjonene 1842–1912 [Doktorgradsavhandling]. Det teologiske menighetsfakultet. Norsk luthersk misjonssamband (NLM). (1948–1965). Kristenliv [Bokserie]. Lunde &
Co. Rokkan, S. (1987). Stat, nasjon, klasse. Essays i politisk sosiologi. Universitetsforlaget.h Predelli, L. N. (1998). Contested Patriarchy and missionary feminism: The
Norwegian missionary society in nineteenth century Norway and Madagascar
[Doktorgradsavhandling]. University of Southern California. Predelli, L. N. (1998). Contested Patriarchy and missionary feminism: The
Norwegian missionary society in nineteenth century Norway and Madagascar [Doktorgradsavhandling]. University of Southern California. Ryen, A. (2002). Husmorlandets siste skanse. I J. P. Knudsen & H. Skjeie (Red.),
Hvitt stakitt og fiberoptikk: regionale myter – regional makt (s. 167–184). Høyskoleforlaget. Seland, B. (2006). Religion på det frie marked. Folkelig pietisme og bedehuskultur. Høyskoleforlaget. 194 konservative holdninger til likestilling på sørlandet Sitering av dette kapitlet: Holmer-Hoven, F. (2020). «East is East and West is West, and never the twain
shall meet.» Et skråblikk på fylkessammenslåingen. I Johnsen, B.E. og Vadum, K. (red.), Grenseløst
Agder. Det som skilte og det som bandt (s. 196–201). Oslo: Cappelen Damm Akademisk. https://doi.
org/10.23865/noasp.111
Lisens: CC BY-NC-ND. konservative holdninger til likestilling på sørlandet Seland, B. (2009). Kjønn og makt – myndige religiøse kvinneroller. Tidsskrift for
kjønnsforskning, 33(1/2), 82–98. https://www.idunn.no/tfk/2009/01-02/art04 Seland, B. (2013). Sørlandsk pietisme? Religion på tvers av grenser. I B. E. Johnsen
(Red.), Sørlandet og utlandet. Transnasjonal kontakt, internasjonal påvirkning
(s. 83–110). Cappelen Damm Høyskoleforlaget. https://doi.org/10.23865/noasp.79 Seland, B. (2020). Det norske bibelbeltet: geografiske og kulturhistoriske perspektiv. Historisk tidsskrift, 99(2), 128–143. https://doi.org/10.18261/issn.1504-2944-2020-
02-04 Seland, B. & Aagedal, O. (2008). Vekkelsesvind. Den norske vekkingskristendommen. Samlaget. Slettan, B. (1986). Prædikerinder og arbeidsbier. Kristelege kvinneroller på
1800-tallet. I O. Aagedal (Red.), Bedehuset. Rørsla, bygda, folket (s. 133–154). Oslo: Samlaget. Slettan, B. (1992). «O, at jeg kunde min Jesum prise…» Folkelig religiøsitet og
vekkelsesliv på Agder på 1800-tallet. Studia humaniora 9, Universitetsforlaget. Slettan, B. (1998). Agders historie 1840–1920. Agder Historielag.t Tjelle, K. F. (1999). Misjonskvinnebevegelsen i Norge. I Norsk tidsskrift for misjon,
53(3), 175–190. https://journals.mf.no/ntm/article/view/3720/3046 Try, H. (1986). Tidleg foreningsframvekst på den norske Skagerrak-kysten, særleg
Agder. I A. Gustavsson, P. Holm & H. Try (Red.), Meddelelser fra Kattegat-
Skagerrak prosjektet nr. 11. Aalborg universitetscenter. Try, H. (1986). Tidleg foreningsframvekst på den norske Skagerrak kysten, særleg
Agder. I A. Gustavsson, P. Holm & H. Try (Red.), Meddelelser fra Kattegat-
Skagerrak prosjektet nr. 11. Aalborg universitetscenter. Vestly, L. M. (2011, 23. september). Myten om den perfekte småbarnsmor
[Debattinnlegg]. Fædrelandsvennen. https://www.fvn.no/mening/i/e06BR/myten-
om-den-perfekte-smaabarnsmor Vestly, L. M. (2011, 23. september). Myten om den perfekte småbarnsmor
[Debattinnlegg]. Fædrelandsvennen. https://www.fvn.no/mening/i/e06BR/myten-
om-den-perfekte-smaabarnsmor Vestly, L. M. (2013, 5. mars). Morshjerte i samfunnsklemma [Kommentar]. Dagen. https://www.dagen.no/meninger/Morshjerte_i_samfunnsklemma-59514 Vestly, L. M. (2013, 5. mars). Morshjerte i samfunnsklemma [Kommentar]. Dagen. https://www.dagen.no/meninger/Morshjerte_i_samfunnsklemma-59514 Wertsch, J. V. (2002). Voices of collective remembering. Cambridge University Press. fi Wertsch, J. V. (2002). Voices of collective remembering. Cambridge University Press Woodhead, L. (2007). Gender differences in religious practice and significance. I J. A. Beckford & N. J. Demerath (Red.), The Sage handbook of the sociology of
religion. Sage. https://doi.org/10.4135/9781848607965 Woodhead, L. (2007). Gender differences in religious practice and significance. I J. A. Beckford & N. J. Demerath (Red.), The Sage handbook of the sociology of
religion. Sage. https://doi.org/10.4135/9781848607965 Øidne, G. (1986). Litt om motsetninga mellom Austlandet og Vestlandet [tidligere
trykt i Syn og Segn 1957]. I O. Aagedal (Red.), Bedehuset. Rørsla, bygda, folket
(s. 40–58). Aagedal, O. (Red.). (1986). Bedehuset. Rørsla, bygda, folket. Samlaget. Aagedal, O. (Red.). (1986). Bedehuset. Rørsla, bygda, folket. Samlaget. 195 kapittel 9 1
Rudyard Kipling: «The Ballad of East and West», Magazine, desember 1889 «East is East and West is West,
and never the twain shall meet.»
Et skråblikk på fylkessammenslåingen Finn Holmer-Hoven Jeg har valgt et udødelig Kipling-sitat som tittel på dette kapitlet, som
en beskrivelse av den politiske tilstanden i Agder før fylkessammen
slåingen.1 Men jeg kunne også ha innledet med et tema fra Charles
Dickens’ bok A tale of two cities – overført til Kristiansand og Arendal –
hvor begge kunne ha blitt vugge for en ny tid. Begge opplevde stagnasjon
og nedgangstider. Den ene klarte å komme seg ut av shippingkrise og
lavkonjunktur, og skapte seg et nytt næringsgrunnlag. Den andre forble
lojal til tradisjonene, og stagnerte. Sett fra min posisjon – dels som observatør, dels som aktør – til kran-
gelen mellom agderfylkene i 50 år, er fusjonen fra nyttår 2020 et tidsskille
av historiske dimensjoner. Det store og avgjørende spørsmålet er om noen hundre års konflikt
og konkurranse mellom Arendal og Kristiansand lar seg viske ut gjen-
nom et stortingsvedtak om fylkessammenslåing. Enkelte har fremstilt
fylkessammenslåingen som en begivenhet på høyde med Bismarcks
samling av Tyskland. Andre har sammenliknet det med en tragedie på
linje med Titanics undergang – i hvert fall hvis vi skal tro tidligere stor-
tingsrepresentant Ingebjørg Godskesen, før Frp sendte henne i eksil som 196 «east is east and west is west, and never the twain shall meet.» valgobservatør i Albania. Og det er dem som har sammenliknet fusjonen
med en fremtidig sammenslåing av Nord- og Sør-Korea. Sammenslåingen ble vedtatt i Aust-Agder fylkesting i desember 2017 med
to stemmers overvekt – ikke nettopp en overveldende velkomst for den nye
fylkeskommunen. Vedtaket utløste 77 kommentarer på Agderpostens nett-
side, hvor ordet forræderi var blant skjellsordene. Det sier litt om stemnin-
gen i øst-fylket når fylkesfusjonen blir vedtatt med knappest mulig flertall. Det er denne mistilliten den nye, sammenslåtte fylkeskommunen nå
må forholde seg til og bearbeide. Den største utfordringen vil bli å for-
ene Kristiansand og Arendal – to byer som har ligget i en århundrelang
kamp om funksjoner, posisjoner og status. Arendal var – og er fortsatt
– handelsborgerskapets by. Handelsstandens sangforening er fortsatt en
betydningsfull sosial institusjon i byen. Og mens de ledende næringslivs-
navn i Kristiansand de siste tiårene har vært gründere som Bjarne Skeie
og Einar Øgrey, Rasmussenkonsernet og bedrifter som National Oilwell,
Aker Kværner, Elkem Solar og Glencore Nikkelverk (tidligere Falcon-
bridge) – er det kjøpmennene Ottersland og Syrdalen som skinner over
Arendals økonomiske firmament. «East is East and West is West,
and never the twain shall meet.»
Et skråblikk på fylkessammenslåingen Som gammel samfunnsviter synes jeg
fortsatt å fornemme sosiale klasseforskjeller i Arendal – holdt levende
av det arendalske handelsaristokrati – som vi ikke lenger finner i andre
norske byer, og heller ikke lenger i Kristiansand, hvor selv klubbforenin-
gen Klubben er blitt en varmestue og et skjenkested for parvenyene.t La meg bare nevne som et apropos en hendelse som bekrefter det aren-
dalske handelsaristokratis utøvende makt i Arendal. For noen år siden
var kjøpmann Ottersland villig til å bevilge 25 millioner til en kreft-
robotmaskin (da Vinci) til Sørlandet sykehus. Men det var på vilkår av at
maskinen ble plassert på sykehuset i Arendal, som verken har eller hadde
personell til å betjene den. Sykehuslegene protesterte, og viste til at skulle
den ha noen funksjon, måtte den plasseres og betjenes av kreftlegene i
Kristiansand. Men sykehusets styreformann gav etter for kjøpmannens
krav – og nå reiser kreftleger fra Kristiansand frem og tilbake til Arendal
for å betjene vidunderet etter kjøpmann Otterslands anvisning. Min tidligere kollega på gamle Agder distriktshøgskole, historikeren
Hans Try, som skrev et bind av Cappelens norgeshistorie, var også opptatt
av konfliktene mellom Arendal og Kristiansand i et historisk perspektiv. 197 kapittel 9 Han trakk linjene helt tilbake til 1641, da Christian Quart gav den nye
byen han grunnla på Sanden – Kristiansand – kjøpstadsprivilegier. Aren-
dal, som til da hadde vært den største handelsbyen mellom Tønsberg og
Stavanger, ble underlagt kjøpstaden Kristiansand, til stor forbitrelse for
arendalittene som måtte ha borgerbrev fra Kristiansand. Selv om Aren-
dal fikk kjøpstadsprivilegier i 1723, måtte borgerne i Arendal betale skatt
til Kristiansand til midten av 1800-tallet. Det er klart at slikt skaper ondt
blod, sinne og frustrasjoner gjennom generasjoner – og det var, ifølge
Hans Try, kimen til den evigvarende konflikten og kivingen mellom
Kristiansand og Arendal helt opp til vår tid. Men kivingen mellom Arendal og Kristiansand har vært mer enn en
bykamp. Det er en grunnleggende landsdelskonflikt som har preget Sør-
landet og agderfylkene i over 100 år, og som har bidratt til at vi som lands-
del har blitt oversett og neglisjert i storting og styringsverk – ødeleggende
for vår vekst og utvikling. Det har vært en regional lidelseshistorie hvor
tid, krefter og ressurser har vært ødet på en destruktiv kamp fylkene og
byene imellom. Haugesund bestrider ikke Stavangers posisjon som regionhoved-
stad, Steinkjer bestrider ikke Trondheims posisjon som Midt-Norges
hovedstad. «East is East and West is West,
and never the twain shall meet.»
Et skråblikk på fylkessammenslåingen Bergen er Vestlandets hovedstad og Tromsø Nord-Norges. Men Norges femte største by har ingen selvfølgelig status som Sørlan-
dets hovedstad. Kristiansand må kjempe med Arendal for hver region
hovedstadsfunksjon som skal plasseres eller utvikles. Samtidig taler ikke
befolkningsutviklingen til Arendals fordel. Mens Grimstad hadde en
befolkningsøkning på 30 prosent i perioden 2010 til 2018, og Kristiansand
26 prosent, var Arendals befolkningsvekst i denne perioden bare 13 pro-
sent. Selv Mandal, som lenge har ligget i en bakevje i Agder, hadde en
økning på nær 18 prosent. Å fremstille Sørlandet som en egen politisk enhet i distriktspolitisk for-
stand, i likhet med Vestlandet, Trøndelag og Nord-Norge, hadde lenge ikke
rot i virkeligheten. For vi har stort sett kranglet innbyrdes med oss selv. By har stått mot by og bygd mot by. Det er til syvende og sist den dypere årsak
til at Sørlandet har stått i stampe og sovet sin Tornerosesøvn så lenge. Og det
er vel grunnen til at det aldri har stått makt bak dets krav. 198 «east is east and west is west, and never the twain shall meet.» Nei, dette er ikke sitat fra en lederartikkel i Fædrelandsvennen anno 2019,
men Vilhelm Krags betraktninger om Sørlandet og sørlendingene i 1919.2
Han var jo også en brennende samfunnsrefser som tok et kraftig oppgjør
med holdningene i de sørlandske by- og bygdesamfunn i sin tid. Sammenslåingen av agderfylkene i dag bringer tankene hen på etab
leringen av Sørlandsforeningen i 1919. Det var en historisk enestående
politisk konstruksjon i norsk sammenheng, som etter hvert omfattet byer,
kommuner og fylkene fra Boknafjorden i Rogaland til Telemark. Forenin-
gens formål var å samarbeide på tvers av fylker og kommuner om felles
oppgaver og løsninger. Og dens fremste oppgave var å realisere Sørlands-
banen, som var den siste store infrastrukturinvesteringen i landsdelen før
E18-utbyggingen mellom Grimstad og Kristiansand 90 år senere. Sørlandsforeningen ble dannet i entusiasmens rus, og ble ledsaget
av Vilhelm Krags høystemte optimisme: «Lenge lå tusmørket over det
store, skjønne land. I dag lysner det liksom. Er det kanskje morgenen som
gryr?» Dette skriver Vilhelm Krag i avisen Tidens Tegn på Sørlandsfore-
ningens stiftelsesdag i Arendal.3 Jostein Andreassen er den som har satt seg mest inn i Sørlandsfore-
ningens liv og levnet. I Fædrelandsvennen hadde han en kronikk i anled-
ning 100-årsdagen for foreningens stiftelse, 15. oktober 1919. Foreningen
ble stiftet i Arendals rådhus. 2
Tidens Tegn, 14. oktober 1919
3
Tidens Tegn, 14. oktober 1919
4
Tidens Tegn, 5. desember 1926 «East is East and West is West,
and never the twain shall meet.»
Et skråblikk på fylkessammenslåingen Og innbydere var 108 ordførere, tre fylkes-
menn, 14 borgermestre, Sørlandets presseforening, 44 institusjoner innen
kommunikasjon og næringsliv samt hele 50 representanter for sørlands-
pressen. Initiativtagerne var Vilhelm Krag og hans fetter, borgermester i
Kristiansand og nyutnevnt fylkesmann i Aust-Agder, Thomas Knudtzon. Men etter åtte år gikk det ad undas med foreningen. Den ble oppløst i
1927, som følge av indre splid og uenighet. I dag forbauser det oss ikke at
det var Arendal som brøt ut og var en av årsakene til splittelsen. Vilhelm
Krag trykket artikkelen «Jorda er sur» i Tidens Tegn, som et bittert opp-
gjør med brustne illusjoner om et sørnorsk fellesskap.4 «Verre enn stei-
nen og flinten i fjellet er nok flinten i menneskenes sinn – naboniddet,
småligheten, hele rasens råtne skavank.» Det var Vilhelm Krags hilsen 199 kapittel 9 til sørlendingene og arendalittene før han trakk seg tilbake til Havbukta
i Ny-Hellesund. Jeg nevner denne historien fordi det er det eneste forsøket på en
slags sammenslutning eller et slags samarbeid mellom agderfylkene før
fusjonsvedtakene i 2017. Og etter fusjonen av agderfylkene er elefanten i
rommet fortsatt Arendal. Konflikten mellom Arendal og Kristiansand vil
ligge som en permanent skygge over ett Agder. Og det er jo et skrøpelig
utgangspunkt for en vellykket fusjon at den ble reddet med to stemmers
overvekt i Aust-Agder fylkesting. Der står vi nå, med et nytt agderfylke som ingen vet hvordan vil fun-
gere. En forsmak på hva vi har i vente er krangelen om arbeidsplasser,
lokaliseringer og kompensasjoner. Det hører selvsagt med til slike fusjo-
ner. Men det hører til sjeldenhetene at Aust-Agders fylkesrådmann
forlangte at hans ansatte skulle ha et halvt hundre tusen kroner i lønns
kompensasjon for å pendle til Kristiansand – nær det dobbelte av hva
norske soldater fikk i krigssonetillegg i Afghanistan. Så her taler vi om en
symbolsk krigssone. For å gjøre fylkesfusjonens absurditeter komplett: Fylkesmannen i
Agder skal lokaliseres til Arendal, mens fylkeskommunens admini
strasjon skal lokaliseres i Kristiansand. Men fordi det er flere ansatte i
fylkeskommunene enn hos fylkesmannen, skal dette balanseres ved at
deler av fylkeskommunens ansatte i Aust-Agder fortsatt skal bli værende
i Arendal. Men konflikten mellom øst og vest på Agder er ikke bare en fylkes-
sak eller en bykonflikt. Konflikten skjærer på langs gjennom Aust-Agder,
hvor det går et mentalt og politisk skille ved Kaldvellfjorden mellom Lille
sand og Grimstad. «East is East and West is West,
and never the twain shall meet.»
Et skråblikk på fylkessammenslåingen Som gammel avismann registrerer jeg at regionaviser
som Stavanger Aftenblad, Bergens Tidende, Adresseavisen og Nordlys
har en relativt jevn dekning i sine nedslagsfelt. Ikke så for Fædrelands
vennen i agderfylkene. Her sank avisens husstandsdekning fra 60 prosent
i Lillesand til fem–seks prosent i Grimstad, og enda mindre i Arendal. Et uttrykk for skismaet i Agder var at enstemmige kommunestyrer i
grensekommunene Lillesand, Birkenes, Iveland samt Evje og Hornnes
søkte overgang til Vest-Agder i 2010, og lot spørsmålet bli avgjort ved
folkeavstemninger ved kommunevalget i 2011. Et overveldende flertall av 200 «east is east and west is west, and never the twain shall meet.» velgerne stemte ja til fylkesskifte. Saken ble behandlet i Stortinget i 2013,
som avviste grenseovergangene, selv om resten av Aust-Agder ville ha fått
flere innbyggere enn Finnmark før fylkessammenslåingen. Hva er det vi samler i ett Agder? Drar vi vestover mot mitt fødested,
Farsund, og videre til Lista og Flekkefjord, finnes det ingen identifika-
sjon eller fellesskapsfølelse med Arendal og aust-egdene. For dem er det
et distrikt og en landsdel som er like fjern som Härjedalen og Jämtland. Mange av innbyggerne i vestfylket har sterkere tilknytning til Brooklyn
enn til Arendal og Aust-Agder. Du kan fortsatt treffe på mennesker på
Lista som har fartet frem og tilbake til Brooklyn, men som aldri har satt
sine ben i Arendal. Så fylkesordfører Arne Thomassen og den politisk nye agderregionen
står foran en formidabel oppgave når de skal prøve å skape en felles iden-
titet for ett Agder – fra Åna-Sira til Gjerstad. Min spådom er at den type konflikter vi opp gjennom årene har opp-
levd – fra hvor et legehelikopter skal stasjoneres til hvilket sykehus som
skal ha ansvaret for tarmkreftoperasjoner og karkirurgi – vil prege og
forsure den politiske debatten på Agder i overskuelig fremtid. Anerkjen-
nelsen av Kristiansand som fylkes- og regionhovedstad tror jeg ligger
lysår inn i fremtiden – om det er i den retning det ligger. Da er det bare å ønske de fylkeskommunalt ansatte god tur fra Aren-
dal til Kristiansand, med et smusstillegg som tilsvarer fem lønnstrinn i
statens regulativ. «East is East and West is West, and never the twain shall meet.» Så
gjenstår det å se om det er dette Kiplingsitatet som best vil beskrive det
fremtidige, sammenslåtte Agderfylket. 201 Bidragsytere Finn Holmer-Hoven, født i 1942, er cand.polit. fra Universitetet i Oslo og
tidligere dosent i offentlig administrasjon ved Agder distriktshøyskole og
politisk redaktør og sjefredaktør i Fædrelandsvennen. Dag Hundstad, født i 1976, er seksjonsleder for Norsk lokalhistorisk
institutt ved Nasjonalbiblioteket. Han er ph.d. fra Universitetet i Bergen
(2013) med avhandlingen Sørlandet – fra terra incognita til sommerferie
land – fire historiske analyser av regionalitet og regionalisme. Han har også
skrevet Klevefolk – historien om en havn (1996), Sørlandske uthavnssam-
funn – rendyrkede sjøfartskulturer (2005), to bygdebøker for Harkmark i
Mandal (2010) og jubileumsboka for Agder Historielag (2015). I tillegg har
han publisert artikler om lokal- og regionalhistorie, turisme, kystkultur
og maritim historie. Leonhard Jansen, født i 1958, er avdelingleder/konservator ved Aust-
Agder museum og arkiv avd. Setesdalsmuseet. Han er cand.philol. fra
Universitetet i Oslo i 1987, og har hovedsaklig arbeidet med lokalhisto-
riske emner fra Setesdal. Han var medarbeider i bygdebokarbeidet i Valle
og forfatter av Valle kultursoge. Han har blant annet skrevet bøkene Svein
Knutsson Hovden – kvedar og sogemann, Allstøtt med deg – Valle spare
bank 150 år og Frå postveg til riksveg – vegar og vegminne langs rv. 9, i
tillegg til lokalhistoriske artikler. Berit Eide Johnsen, født i 1955, er professor i historie ved Universitetet i
Agder. Hun er dr.art. fra Universitetet i Bergen (1998) med avhandlingen
Rederistrategi i endringstid: sørlandsk skipsfart fra seil til damp og motor,
fra tre til jern og stål: 1875–1925 (utgitt som bok 2001). Hun har også skrevet 202 bidragsytere bøkene Han sad i prisonen -: sjøfolk i engelsk fangenskap 1807–1814 (1993),
Sørlandsk skipsfart 1600–1920 (2016) (sammen med Gustav Sætra) og Lille
sands historie 1800–1850 (2017). Hun er engasjert som forfatter av ytter
ligere to bind av Lillesands historie (fra 1850 og fram til i dag). De senere
årene har hun også publisert artikler om migrasjon og turismens historie. bøkene Han sad i prisonen -: sjøfolk i engelsk fangenskap 1807–1814 (1993),
Sørlandsk skipsfart 1600–1920 (2016) (sammen med Gustav Sætra) og Lille
sands historie 1800–1850 (2017). Hun er engasjert som forfatter av ytter
ligere to bind av Lillesands historie (fra 1850 og fram til i dag). De senere
årene har hun også publisert artikler om migrasjon og turismens historie. Nils Martinius Justvik, født i 1957, er førsteamanuensis i historie ved
Universitetet i Agder. Han er dr. art. fra Universitetet i Oslo (2007) med
avhandlingen Kristenfolkets forhold til idrett. Bidragsytere Endringer på Sørlandet i
etterkrigstida (utgitt som bok 2012). Han har de siste årene arbeidet med
Agders idrettshistorie og på oppdrag fra de to idrettskretsene skrevet
bøkene Idrett i Sør. Vest-Agders Idrettskrets 100 år 1917–2017 (2017) og Fra
hav til hei. En fortelling om idrett i Aust-Agder (2018). Han har skrevet
flere artikler knyttet til de tre bøkenes temaer. Jon P. Knudsen, født i 1956, er professor i samfunnsgeografi ved Univer-
sitetet i Agder. Han er fil.dr. fra Lunds Universitet (1994) med avhandlin-
gen Kulturspredning i et strukturelt perspektiv. Eksemplifisert ved politisk
og religiøs endring under moderniseringen av det norske samfunn. Han
har skrevet en rekke artikler og bokbidrag om politiske og kulturelle for-
hold i Norge og Norden. I perioden 1995–2000 var han politisk redaktør
i Fædrelandsvennen. Han satt i 2017–2018 som medlem av det regjerings-
oppnevnte ekspertutvalget for regionreformen. Han er for tiden også
styreleder ved fakultet for landskap og samfunn ved Norges miljø- og
biovitenskapelige universitet (NMBU). May-Linda Magnussen, født i 1973, er førsteamanuensis i sosiologi ved
Universitetet i Agder. Hun har en doktorgrad i sosiologi fra Universitetet
i Oslo og forsker på familie- og arbeidsliv i et kjønns- og migrasjons
perspektiv. Hennes nyeste publikasjoner er: Jeg er klar til å bidra. Utforsk
ning og utfordring av bakkebyråkraters kategorisering av flyktninger som
prøver å komme i jobb i dagens Norge (Tidsskrift for velferdsforskning,
nr. 1, 2020) og Men’s Family Breadwinning in today’s Norway: A Blind Spot
in the Strive for Gender Equality (NORA – Nordic Journal of Feminist
and Gender Research, 2020). 203 bidragsytere Bjørg Seland, født i 1947, er professor emeritus i historie ved Universi-
tetet i Agder. Hun er dr. philos. fra Universitetet i Bergen 2002. Hennes
forskningsfelt omfatter sosial- og kulturhistoriske emner i tidsrommet
ca. 1800–1940, med studier knyttet til sosial organisering i bondesam-
funnet, kjønnsrolleproblematikk og framveksten av religiøse bevegelser. Innenfor sistnevnte fagområde har hun bl.a. annet utgitt Religion på det
frie marked. Folkelig pietisme og bedehuskultur (2006), Vekkelsesvind. Den norske vekkingskristendommen (i samarbeid med Olaf Aagedal,
2008) og «Synepiger» og «Sværmersker». Religiøs mystikk mellom tradi-
sjon og modernitet (2011). Roger Tronstad, født i 1955, er historiker og førstearkivar i Arkivverket,
Statsarkivet i Kristiansand. Han har utgitt bøkene Jøder på Agder 1851–
1945 (2015) og Frimodighet med etterspill. Nicolai Wergeland i menings
kamp og rettsstrid (2018). Bidragsytere Han har også publisert flere artikler med ulike
temaer fra Agders historie, blant annet om politiske valg, stemmerett og
fattigdom. Nå arbeider han med bok om antisemittisme på Agder inntil
1945. 204
|
https://openalex.org/W3039306512
|
https://jurnal.ugm.ac.id/jpkm/article/download/50379/31364
|
Indonesian
| null |
Peningkatan Minat Budi Daya Melalui Pelatihan Produksi Pakan Ikan Mandiri dan Akuaponik
|
Jurnal Pengabdian Kepada Masyarakat (Indonesian Journal of Community Engagement)/Jurnal pengabdian kepada masyarakat (Indonesian journal of community engagement)
| 2,021
|
cc-by-sa
| 3,288
|
Submisi: 04 Oktober 2019 ; Revisi: 20 April 2020; Penerimaan: 28 April 2020 4 Oktober 2019 ; Revisi: 20 April 2020; Penerimaan: 28 April 2020 Kata Kunci:
Ikan lele
Ketahanan
pangan
Pakan
alternatif
Remaja Kata Kunci:
Ikan lele
Ketahanan
pangan
Pakan
alternatif
Remaja Abstrak Remaja merupakan figur yang sangat berperan dalam proses
pembangunan nasional dan mentalitas nasional. Aktivis pemuda di Dusun Jetis,
Desa Mulyoagung dipilih sebagai mitra target dalam program kemitraan ini
karena dianggap mampu menjembatani pengusul dengan masyarakat. Tujuan
kegiatan ini adalah untuk meningkatkan keterampilan remaja di bidang
pertanian dan perikanan melalui pelatihan pembuatan pakan ikan mandiri dan
budi daya ikan menggunakan sistem akuaponik demi mencapai ketahanan
pangan nasional melalui pengembangan potensi lokal. Metode yang digunakan
dalam kegiatan ini adalah pelatihan secara langsung tentang teknik pembuatan
pakan ikan secara mandiri dengan memanfaatkan bahan baku lokal dan
pelatihan budi daya ikan menggunakan sistem akuaponik. Hasil dari kegiatan ini
adalah peningkatan ketertarikan remaja terhadap akuaponik sebesar 30% dan
peningkatan pemahaman remaja tentang pembuatan pakan ikan sebesar 30%. Kesimpulan dari kegiatan ini adalah bahwa pelatihan dapat meningkatkan
ketertarikan dan pemahaman remaja perihal akuaponik dan pembuatan pakan
ikan mandiri sehingga di masa mendatang diharapkan akan semakin banyak
remaja yang menekuni bidang pertanian dan perikanan. Abstract Teenagers are figures who are very involved in the process of national
development and national mentality. Youth activists in Jetis, Mulyoagung village
were chosen as target partners in this engagement program because they were
considered capable of bridging the proposer and the community. The purpose of
this activity is to improve the skills of the teenagers in agriculture and fisheries
through training the aquaponic system and produce alternative fish feed for the
sake of achieving national food security through developing local potential. The
method used in this activity is training on how to make alternative fish feed by
utilizing local raw materials and training in aquaculture using an aquaponic
system. The results showed that teenage interest in aquaponics increased by
30% and understanding the production of alternative fish feed also increased by
30%. The conclusion obtained from this activity is that additional training can
increase the interest and understanding of teenagers in aquaponics and the
production of alternative fish feed, so hoped that more teenagers will pursue
agriculture and fisheries. Indonesian Journal of Community Engagement
Jurnal Pengabdian kepada Masyarakat Indonesian Journal of Community Engagement
Jurnal Pengabdian kepada Masyarakat Indonesian Journal of Community Engagement Jurnal Pengabdian kepada Masyarakat Vol. 6, No. 2, Juni 2020, Hal. 112 – 117
DOI: http://doi.org/ 10.22146/jpkm.50376 ISSN 2460-9447 (print), ISSN 2541-5883 (online)
*Corresponding author : Zubaidah
1Prodi Akuakultur, Fakultas Pertanian Peternakan, Universitas Muhammadiyah Malang, Jl. Raya Tlogomas 246, Tegalgondo, Karang Ploso, Jawa
Timur, Indonesia
Email: aniszubaidah@umm.ac.id
Copyright © 2019 Jurnal Pengabdian kepada Masyarakat (Indonesian Journal of Community Engagement
This work is distributed under a Creative Commons Attribution-ShareAlike 4.0 International License Kata Kunci:
Ikan lele
Ketahanan
pangan
Pakan
alternatif
Remaja Peningkatan Minat Budi Daya Melalui Pelatihan Produksi Pakan
Ikan Mandiri dan Akuaponik g
y
Ikan Mandiri dan Akuaponik
Anis Zubaidah1*, Ganjar Adhywirawan Sutarjo1, Nur Ocvanny Amir2, Ridho Firmandhaka1
1Prodi Akuakultur, Fakultas Pertanian Peternakan, Universitas Muhammadiyah Malang
2Prodi Agribisnis, Fakultas Pertanian Peternakan, Universitas Muhammadiyah Malang Anis Zubaidah1*, Ganjar Adhywirawan Sutarjo1, Nur Ocvanny Amir2, Ridho Firmandhaka1
1Prodi Akuakultur, Fakultas Pertanian Peternakan, Universitas Muhammadiyah Malang
2Prodi Agribisnis, Fakultas Pertanian Peternakan, Universitas Muhammadiyah Malang 1. PENDAHULUAN strategis dan potensi sumber daya yang tersedia. Selain
itu, peningkatan jumlah penduduk dunia yang
menyebabkan kebutuhan ikan semakin meningkat,
pergeseran pola konsumsi masyarakat ke produk
perikanan, serta tuntutan penyediaan makanan bermutu Sektor perikanan merupakan salah satu sektor yang
dapat menunjang pertumbuhan ekonomi di Indonesia. Pembangunan budi daya perikanan berpeluang besar
untuk dilakukan apabila dilihat dari lingkungan ISSN 2460-9447 (print), ISSN 2541-5883 (online)
*Corresponding author : Zubaidah
1Prodi Akuakultur, Fakultas Pertanian Peternakan, Universitas Muhammadiyah Malang, Jl. Raya Tlogomas 246, Tegalgondo, Karang Ploso, Jawa
Timur, Indonesia
Email: aniszubaidah@umm.ac.id
Copyright © 2019 Jurnal Pengabdian kepada Masyarakat (Indonesian Journal of Community Engagement
This work is distributed under a Creative Commons Attribution-ShareAlike 4.0 International Licens ISSN 2460-9447 (print), ISSN 2541-5883 (online) ISSN 2460-9447 (print), ISSN 2541-5883 (online) ISSN 2460-9447 (print), ISSN 2541-5883 (online)
*Corresponding author : Zubaidah
1Prodi Akuakultur, Fakultas Pertanian Peternakan, Universitas Muhammadiyah Malang, Jl. Raya Tlogomas 246, Tegalgondo, Karang Ploso, Jawa
Timur, Indonesia
Email: aniszubaidah@umm.ac.id
Copyright © 2019 Jurnal Pengabdian kepada Masyarakat (Indonesian Journal of Community Engagement). This work is distributed under a Creative Commons Attribution-ShareAlike 4.0 International License. Vol. 6, No. 2,
www.jurnal.ugm.ac.id/jpkm 112 p
g
i Akuakultur, Fakultas Pertanian Peternakan, Universitas Muhammadiyah Malang, Jl. Raya Tlogomas 246, Tegalgondo, Karang Ploso, Jawa
Indonesia Copyright © 2019 Jurnal Pengabdian kepada Masyarakat (Indonesian Journal of Community Engagement). This work is distributed under a Creative Commons Attribution-ShareAlike 4.0 International License. Copyright © 2019 Jurnal Pengabdian kepada Masyarakat (Indonesian Journal of Community Engagement). This work is distributed under a Creative Commons Attribution-ShareAlike 4.0 International License. 112 Vol. 6, No. 2, Vol. 6, No. 2,
www.jurnal.ugm.a www.jurnal.ugm.ac.id/jpkm Peningkatan minat budi daya pakan ikan mandiri dan akuaponik Zubaidah ET AL tinggi dan memenuhi syarat kesehatan menjadi alasan
pentingnya pembangunan budi daya perikanan. Sayangnya, kemajuan teknologi di era globalisasi saat
ini justru tidak berpihak pada penyediaan sumber daya
manusia yang mumpuni di bidang perikanan. Hal
tersebut sesuai dengan pernyataan dari Kementerian
Kelautan dan Perikanan bahwa milenial tidak tertarik
pada bidang perikanan (Victoria, 2019). dalamnya pembudi daya ikan) jumlahnya menurun
dibandingkan tahun 2010, yaitu hanya sebesar 12%
(Desa Mulyoagung, 2013). Penurunan tersebut juga
perlu diperhatikan karena dapat berpengaruh terhadap
ketahanan pangan nasional. Desa Mulyoagung terdiri atas beberapa dusun. Setiap dusun memiliki kumpulan remaja yang
tergabung dalam karang taruna. Di Dusun Jetis,
misalnya, terdapat ± 20 remaja yang aktif dalam karang
taruna. Remaja penggerak karang taruna di Dusun Jetis
inilah yang dipilih sebagai target mitra dalam program
kemitraan ini karena dianggap mampu menjembatani
antara pengusul dengan masyarakat. Dalam program
ini, mereka diikutsertakan dalam pelatihan pembuatan
pakan ikan mandiri dengan memanfaatkan potensi lokal
dan pelatihan pembudidayaan ikan dengan sistem
akuaponik. Akuaponik merupakan gabungan teknologi
budi daya ikan dan tanaman dalam satu wadah
(Fathulloh & Budiana, 2015). Teknologi tersebut telah
dimanfaatkan oleh negara-negara maju, khususnya
yang
memiliki
keterbatasan
lahan
untuk
mengoptimalkan produktivitas biota perairan dan
terbukti dapat meningkatkan kapasitas produksi serta
perbaikan kualitas air (Nugroho et al., 2012). Pelatihan
ini diharapkan dapat meningkatkan keterampilan
remaja, khususnya di bidang pertanian dan perikanan
demi pencapaian ketahanan pangan nasional melalui
pengembangan potensi lokal. Vol. 6, No. 2, ISSN 2460-9447 (print), ISSN 2541-5883 (online) Pada era globalisasi yang ditandai dengan
perubahan yang begitu cepat dan tidak terduga akibat
kemajuan teknologi komunikasi dan informasi,
generasi milenial (remaja) mudah menjadi korban dari
setiap perubahan dan perkembangan (Taopan et al.,
2019). Perubahan yang berpengaruh besar pada
kehidupan generasi milenial adalah perubahan yang
terkait dengan kegiatan ekonomi dan perkembangan
teknologi. Saat ini, kurangnya minat remaja untuk
terjun di bidang perikanan menjadi hal yang perlu
diperhatikan karena dapat mengancam ketahanan
pangan nasional (Romdiyati, 2015). Saat ini semakin
banyak desa yang ditinggalkan oleh para remajanya
untuk bekerja di kota-kota besar yang lebih
menjanjikan daripada menjadi petani atau pembudi
daya ikan. Selain itu, banyak remaja yang menjadi
pengangguran karena tidak memiliki keterampilan,
padahal persaingan di bidang industri sangat tinggi. Para remaja umumnya berpikir bahwa budi daya
ikan adalah pekerjaan yang melelahkan, membosankan,
dan harus berpanas-panasan, hujan-hujanan, serta
menunggu lama untuk mendapat hasil panen yang
memuaskan dan mendapatkan uang. Selain itu, budi
daya ikan dipandang sebagai pekerjaan kelas dua. Pandangan tersebut diperkuat dengan masih sempitnya
kesadaran
dan
pemahaman
masyarakat
tentang
pentingnya potensi lokal. Paradigma tersebut dapat
berimbas pada sektor perikanan, terutama sektor
ketahanan dan kedaulatan pangan di Indonesia pada
masa yang akan datang karena berkurangnya minat
remaja menjadi pembudi daya. Dalam bidang
perikanan, remaja diharapkan mampu menciptakan
sistem atau konsep-konsep baru, bahkan teknologi baru
yang
dapat
digunakan
untuk
memaksimalkan
produktivitas meskipun dengan lahan yang minim dan
memanfaatkan potensi lokal daerah masing-masing. 2. METODE Program ini dilaksanakan selama delapan bulan (Mei
sampai Desember 2019) pada Karang Taruna Desa
Mulyoagung, Kecamatan Dau, Kabupaten Malang. Metode yang digunakan adalah pelatihan bertahap. 2.1 Pelatihan budi daya ikan dan sayuran dengan
metode akuaponik Program ini dilaksanakan selama delapan bulan (Mei
sampai Desember 2019) pada Karang Taruna Desa
Mulyoagung, Kecamatan Dau, Kabupaten Malang. Metode yang digunakan adalah pelatihan bertahap. 2.1 Pelatihan budi daya ikan dan sayuran dengan
metode akuaponik Pelatihan dilakukan dengan memberikan bantuan
teknologi dan benih untuk budi daya ikan dengan
sistem akuaponik, memberikan dua buah kolam serta
sarana dan prasarana lengkap untuk budi daya
akuaponik kepada mitra, serta melakukan pelatihan
teknik budi daya ikan dengan cara yang benar dan
sesuai dengan Cara Budi Daya Ikan yang Baik (CBIB)
(Direktorat Jenderal Perikanan Budi Daya, 2008). Desa Mulyoagung terletak di ketinggian rata-rata
± 600 mdpl dan berhawa sejuk karena terletak di
kawasan lereng gunung. Desa Mulyoagung merupakan
desa tujuan perpindahan penduduk dari kota dan luar
daerah/ provinsi. Hal tersebut menyebabkan penduduk
Desa Mulyoagung bersifat heterogen dan tata cara
kehidupan penduduknya yang semula bersifat pedesaan
berubah menjadi perkotaan. Kehadiran para pendatang
juga berpengaruh terhadap mata pencaharian penduduk
yang kemudian didominasi oleh pengusaha/ swasta,
yaitu sebesar 49%. Penduduk yang bertani (termasuk di Pelatihan dimulai dengan membersihkan lahan,
meratakan permukaan tanah, merakit besi sebagai
rangka kolam berbentuk bundar, dan memasang terpal
(Gambar 3). Langkah selanjutnya adalah menata sistem
akuaponik serta melakukan persiapan penebaran ikan
dan penyemaian bibit sayuran. Persiapan penebaran
ikan dilakukan dengan aklimatisasi (meletakkan ikan
yang ada dalam kantong plastik ke dalam kolam hingga
plastik mengembun) selama ± 30 menit. Setelah itu,
ikan siap ditebarkan di kolam. Penyemaian bibit 3 www.jurnal.ugm.ac.id/jpkm 113 Peningkatan minat budi daya pakan ikan mandiri dan akuaponik Zubaidah ET AL dilakukan pada trypot plastik (pot untuk penyemaian
benih) dengan menggunakan media tanah yang telah
diberi pupuk. Setelah bibit tumbuh setinggi ±10 cm,
bibit tersebut dipindahkan ke pot plastik dan diletakkan
di lubang akuaponik (Gambar 1). setempat melalui partisipasi aktif dan penerapan
keterbaruan teknologi. Data yang diperoleh kemudian
disajikan dalam bentuk grafik dan dianalisis secara
deskriptif. Gambar 1. Peletakkan bibit pada akuaponik dengan sistem akuaponik Pelatihan dan pendampingan budi daya ikan dengan
sistem akuaponik dilaksanakan di lokasi mitra. Pelatihan dimulai dengan pemberian sumbangan
instalasi akuaponik, terdiri atas kolam terpal bundar
berdiameter 1,5 m sebanyak dua buah yang dilengkapi
dengan setting aerasi, inlet, dan outlet serta sarana dan
prasarana untuk hidroponik. Kegiatan dilanjutkan
dengan setting kolam dan akuaponik serta pengelolaan
air untuk persiapan budi daya tanaman dan sayuran. Tujuan pelatihan ini adalah memberikan pemahaman
kepada mitra terkait persiapan budi daya dan sistem
budi daya untuk mendapatkan hasil yang optimal. Kegiatan ini diharapkan dapat memotivasi remaja
karang taruna di Dusun Jetis untuk mengembangkan
budi daya ikan demi ketahanan pangan di masa
mendatang. Berdasarkan hasil evaluasi diperoleh data
peningkatan minat budi daya pada remaja Karang
Taruna Dusun Jetis, Desa Mulyoagung setelah
pelaksanaan kegiatan pelatihan (Gambar 2). Gambar 1. Peletakkan bibit pada akuaponik 3. HASIL DAN PEMBAHASAN Kegiatan yang telah dilaksanakan meliputi pelatihan
dan pendampingan budi daya ikan menggunakan sistem
akuaponik serta pelatihan pembuatan pakan ikan
mandiri. Vol. 6, No. 2, 2.2 Pelatihan pembuatan pakan ikan mandiri
berbasis potensi lokal Penyusunan formulasi pakan
dilakukan dengan
program
Microsoft
Excel
untuk
menyesuaikan
komposisi dan kandungan nutrisi bahan hingga
diperoleh kadar protein yang diinginkan, yaitu ± 30%. Bahan-bahan yang digunakan dalam proses pembuatan
pakan antara lain tepung silase ikan, tepung daun
singkong, tepung tapioka, bekatul, vitamin mix, dan
molasse. Bahan-bahan
tersebut
kemudian
diformulasikan sesuai dengan kebutuhan nutrisi ikan
lele (Tabel 1). Formulasi pakan ikan dibuat oleh tim
berdasarkan beberapa hasil penelitian tentang bahan
penyusun pakan ikan alternatif (Zubaidah, 2011;
Lazaroni & Sutarjo, 2013). Gambar 2. Ketertarikan responden terhadap akuaponik sebelum
dan sesudah pelatihan
0
10
20
30
40
50
60
70
80
90
100
tertarik
tidak tertarik
tidak tahu
Jumlah responden (%)
Ketertarikan responden terhadap akuaponik
Sebelum
Sesudah Sebelum
Sesudah Tabel 1. Komposisi bahan pakan ikan lele Bahan Pakan
Komposisi (%)
Tepung silase ikan
40
Tepung daun singkong
20
Tepung tapioka
15
Bekatul
15
Vitamin mix
5
Molasse
5 Gambar 2. Ketertarikan responden terhadap akuaponik sebelum
dan sesudah pelatihan Gambar 2. Ketertarikan responden terhadap akuaponik sebelum
dan sesudah pelatihan Evaluasi kualitas pakan ikan mandiri dilakukan
dengan menganalisis proksimat pakan di Laboratorium
Nutrisi Jurusan Perikanan, Universitas Muhammadiyah
Malang. Ketertarikan remaja karang taruna di Dusun Jetis
pada sistem akuaponik dipengaruhi oleh berbagai
faktor, antara lain faktor biaya dan penghasilan serta
keterampilan yang berkaitan dengan akuaponik. Sebelum ada kegiatan pelatihan, mereka mengaku
hanya mengetahui kegiatan akuaponik dari media
massa tanpa mengetahui kerja sistem tersebut serta
teknik membuat rangkaiannya. 2.3 Evaluasi pelaksanaan program 2.3 Evaluasi pelaksanaan program Evaluasi pelaksanaan program dilakukan sebelum dan
setelah kegiatan. Proses evaluasi dilakukan dengan
metode wawancara dan pengisian kuesioner tentang
keberhasilan program, baik secara fisik maupun
respons khalayak sasaran atau mitra dan masyarakat www.jurnal.ugm.ac.id/jpkm
114 114 Vol. 6, No. 2, Peningkatan minat budi daya pakan ikan mandiri dan akuaponik Zubaidah ET AL Gambar 4. Peningkatan pemahaman remaja terkait pembuatan
pakan ikan dengan bahan baku berbasis potensi lokal
0
10
20
30
40
50
60
70
80
90
100
Paham
Tidak Paham
Tidak tahu
Jumlah responden (%)
Pemahaman responden terhadap pembuatan pakan ikan
sebelum
sesudah Pelatihan ini dapat memberikan pemahaman
kepada remaja karang taruna di Dusun Jetis terkait budi
daya ikan dengan sistem akuaponik. Prinsip kerja
akuaponik adalah mengalirkan air kolam ke dalam
talang-talang air yang sudah dilengkapi dengan media
tanam serta bibit tanaman. Media tanam dan akar
tanaman yang tumbuh berfungsi dalam proses
pengolahan air kolam yang kemudian dialirkan kembali
ke dalam kolam ikan (Maharani & Sari, 2016). Proses
pengolahan
air
kolam
dilakukan
dengan
cara
penyerapan senyawa nitrat oleh akar-akar tanaman
sebagai nutrisi untuk pertumbuhan tanaman (Damanik
et al., 2018). Kegiatan budi daya ikan dengan sistem
akuaponik juga dapat diterapkan pada lahan sempit
serta
tidak
membutuhkan
kerja
ekstra
dalam
pelaksanaannya. Hal
inilah
yang
kemudian
meningkatkan jumlah mitra target yang tertarik
terhadap akuaponik, yakni yang sebelumnya hanya
berjumlah 30% kemudian menjadi 60%. Gambar 4. Peningkatan pemahaman remaja terkait pembuatan
pakan ikan dengan bahan baku berbasis potensi lokal Berdasarkan Gambar 4 di atas diketahui bahwa
terdapat
peningkatan
pemahaman
remaja
yang
signifikan terkait produksi pakan ikan secara mandiri
dengan memanfaatkan bahan-bahan alternatif. Pakan
ikan merupakan parameter terpenting dalam usaha budi
daya perikanan. Ketersediaan jumlah pakan sangat
berpengaruh pada pertumbuhan dan kelangsungan
hidup ikan yang dibudidayakan. Pada proses budi daya
ikan, khususnya dalam kegiatan pembesaran, faktor
terpenting adalah jumlah ketersediaan pakan yang
cukup. 3.2 Pelatihan pembuatan pakan ikan mandiri 3.2 Pelatihan pembuatan pakan ikan mandiri
Dalam usaha budi daya ikan, pakan merupakan
komponen utama yang membutuhkan biaya produksi
paling tinggi (70%) (Purwadi, 2016). Oleh karena itu,
keterampilan
dalam
membuat
pakan
mandiri
merupakan hal wajib yang perlu dimiliki oleh setiap
pembudi
daya. Hal
tersebut
yang
mendasari
pelaksanaan pelatihan pembuatan pakan ikan mandiri. Pelatihan dilaksanakan pada 14–21 Juli 2019. Tujuan
pelatihan adalah untuk membekali remaja karang
taruna di Dusun Jetis dengan keterampilan membuat
pakan ikan sehingga dapat menekan biaya produksi. Pelatihan ini juga menekankan pemanfaatan kearifan
lokal guna meningkatkan nilai tambah dan mengurangi
polusi (limbah). Kegiatan ini diikuti dengan antusias
oleh peserta. Hal itu terlihat dari keaktifan peserta
dalam sesi diskusi dan proses pembuatan akuaponik
(Gambar 3). Setelah
pelatihan
terdapat
peningkatan
pemahaman remaja terkait produksi pakan ikan secara
mandiri dengan memanfaatkan bahan-bahan alternatif. Pakan ikan merupakan parameter terpenting dalam
usaha budi daya ikan. Ketersediaan jumlah pakan
sangat
berpengaruh
pada
pertumbuhan
dan
kelangsungan hidup ikan yang dibudidayakan. Pada
proses budi daya ikan, khususnya pada fase
pembesaran, faktor yang terpenting adalah ketersediaan
pakan yang cukup. Salah satu bahan baku alternatif yang dapat
digunakan untuk membuat pakan ikan adalah tepung
daun singkong. Tepung daun singkong memiliki
kandungan protein sebesar 30,24%, lemak 5,60%, dan
serat kasar 15,80% (Syahrizal et al., 2013). Oleh karena
itu, bahan baku daun singkong dapat dimanfaatkan
dalam formulasi pakan ikan untuk mencukupi
kebutuhan protein nabati dan mengganti ketersedian
bahan baku kedelai yang terbatas. Selain itu,
pemanfaatan tepung daun singkong juga bertujuan
untuk menekan biaya pembuatan pakan sehingga
harganya lebih terjangkau. Hasil penelitian yang telah
dilakukan oleh Suwarsito et al., (2017) menunjukkan
bahwa pemberian tepung daun singkong dapat
berpengaruh nyata terhadap pertambahan berat dan
panjang ikan nila. Pakan ikan hasil kegiatan pelatihan
dapat dilihat pada Gambar 5. Gambar 3. Kegiatan pemasangan kolam untuk akuaponik Gambar 3. Kegiatan pemasangan kolam untuk akuaponik Vol. 6, No. 2, 115 www.jurnal.ugm.ac.id/jpkm Peningkatan minat budi daya pakan ikan mandiri dan akuaponik Zubaidah ET AL Gambar 5. Pakan hasil kegiatan pelatihan Direktorat Jenderal Perikanan Budi Daya. (2008). Cara
Budi Daya Ikan yang Baik (CBIB). Kementerian
Kelautan dan Perikanan, Jakarta. Direktorat Jenderal Perikanan Budi Daya. (2008). Cara
Budi Daya Ikan yang Baik (CBIB). Kementerian
Kelautan dan Perikanan, Jakarta. Fathulloh, A. S. & Budiana, N. S. (2015). Akuaponik
Panen Sayur Bonus Ikan. Jakarta: Penebar
Swadaya. Lazaroni, J. L. & Sutarjo, G. A. (2013). UCAPAN TERIMA KASIH Kegiatan ini terlaksana berkat pendanaan dari
Kementrian RISTEKDIKTI dengan skema PkM
(Pengabdian kepada Masyarakat) 2019. 3.2 Pelatihan pembuatan pakan ikan mandiri Pengaruh
Pemanfaatan
Silase
Ikan
sebagai
Bahan
Penyusun Diet terhadap Retensi Protein, Retensi
Lemak dan Kualitas Daging Ikan Sidat (Anguilla
bicolor) (Laporan Penelitian). Jurusan Perikanan
UMM Malang. Maharani, N. A. & Sari, P. N. (2016). Penerapan
Aquaponic sebagai Teknologi Tepat Guna
Pengolahan Limbah Cair Kolam Ikan di Dusun
Kergan,
Tirtomulyo,
Kretek,
Bantul,
Yogyakarta. Indonesian Journal of Community
Engagement, 1(2): 172—182. Diakses dari
https://jurnal.ugm.ac.id/jpkm/article/view/10603 Gambar 5. Pakan hasil kegiatan pelatihan Gambar 5. Pakan hasil kegiatan pelatihan Ikan dan sayuran yang dihasilkan dari kegiatan ini
memiliki keunggulan, yakni bersifat organik, aman,
sehat, dan halal karena dipelihara dengan cara higienis
dan
tanpa
menggunakan
bahan-bahan
kimiawi
(sintetis). Pakan ikan yang dihasilkan juga diharapkan
akan dapat bersaing dengan kualitas pakan ikan
pabrikan. Harga pakan mandiri juga lebih terjangkau,
yaitu Rp. 8.500/ kg daripada harga pakan produksi
pabrik, yaitu Rp. 12.500/ kg. Nugroho, R. A, Pambudi, L. T, Chilmawati, D., &
Haditomo, A. H. C. (2012). Aplikasi Teknologi
Aquaponic pada Budi Daya Ikan Air Tawar
untuk Optimalisasi Kapasitas Produksi. Jurnal
Saintek Perikanan, 8(1): 46—51. Diakses dari
https://doi.org/10.14710/ijfst.8.1.46-51 Purwadi. (2016). Peternak Mengeluh, 70% Biaya untuk
Pakan. Diakses
dari
https://www.radarcirebon.com/peternak-
mengeluh-70-persen-biaya-untuk-pakan. html/ 4. KESIMPULAN Purwaningsih. (2008). Ketahanan Pangan: Situasi,
Permasalahan, Kebijakan, dan Pemberdayaan
Masyarakat. Jurnal Ekonomi Pembangunan,
9(1): 1—27. DOI:10.23917/jep.v9i1.1028 Kegiatan pelatihan pembuatan pakan ikan mandiri dan
budi daya ikan dengan sistem akuaponik yang diikuti
oleh pemuda Karang Taruna Dusun Jetis, Desa
Mulyoagung, Kabupaten Malang dapat dilaksanakan
dengan baik dan lancar. Manfaat kegiatan yang telah
dilaksanakan adalah memberikan pengetahuan baru
dan meningkatkan minat peserta perihal budi daya ikan
dan sayuran dengan sistem akuaponik serta pembuatan
pakan ikan secara mandiri. Kegiatan ini juga dapat
meningkatkan pemanfaatan sumber daya lokal dan
pemenuhan pangan lokal secara mandiri. Romdiyati. (2015). Minat Bertani Generasi Muda
Menurun, Indonesia Terancam Krisis Petani. Diakses dari https://lipi.go.id/ Suwarsito, Apreli, N. N., & Mulia, D. S. (2017). Pengaruh pemberian kombinasi tepung daun
singkong (Manihot utilisima) dan tepung ikan
rucah terhadap pertumbuhan dan kelangsungan
hidup
ikan
nila
(Oreochromis
niloticus). Sainteks,
14(2),
105
–
112. DOI;10.30595/sainteks.v14i2.4258 Syahrizal, Ghofur, M., & Fakhrurrozi. (2013). Pemanfaatan
Daun
Singkong
(Manihot
utilissima) Tua sebagai Pakan Ikan Gurami
(Osphronemus gouramy. Lac). Jurnal Ilmiah
Universitas Batanghari Jambi, 13(4), 107—112. https://media.neliti.com/media/publications/225
613-pemanfaatan-daun-singkong-manihot-
utilis-dfc1d253.pdf Vol. 6, No. 2, Zubaidah, A. (2011). Pengujian Berbagai Bahan Perekat
terhadap Kualitas Kimia Pakan Ikan (Skripsi).
Universitas Muhammadiyah Malang, Malang. Vol. 6, No. 2, Peningkatan minat budi daya pakan ikan mandiri dan akuaponik DAFTAR PUSTAKA Taopan Y. F., Oedjoe, M. R., & Sogen, A. N. (2019). Dampak Perkembangan Teknologi Informasi
dan Komunikasi terhadap Perilaku Moral
Remaja di SMA Negeri 3 Kota Kupang. Jurnal
Kependidikan: Jurnal Hasil Penelitian dan
Kajian Kepustakaan di Bidang Pendidikan,
Pengajaran, dan Pembelajaran, 5(1), 61—74. Diakses
dari
http://ojs.ikipmataram.ac.id/index.php/jurnalkep
endidikan/article/view/1395 Damanik, B. H., Hamdani, H., Riyantini, I., & Herawati,
H. (2018). Uji efektivitas bio filter dengan
tanaman air untuk memperbaiki kualitas air pada
sistem akuaponik ikan lele sangkuriang (Clarias
gariepinus). Jurnal Perikanan dan Kelautan,
9(1):
134
–
142. Diakses
dari
http://jurnal.unpad.ac.id/jpk/article/view/18233 Desa Mulyoagung. (2013). Gambaran Umum Desa
Mulyoagung. Diakses
dari Desa Mulyoagung. (2013). Gambaran Umum Desa
Mulyoagung. Diakses
dari
https://desamulyoagung.blogspot.com/ y
g
g
https://desamulyoagung.blogspot.com/ Vol. 6, No. 2, 116 www.jurnal.ugm.ac.id/jpkm
116 Zubaidah ET AL Victoria, A. O. (2019). Kementerian KKP Keluhkan
Generasi
Milenial
Tak
Tertarik
Bidang
Perikanan. Diakses
dari
https://katadata.co.id/berita/2019/10/12/kemente
rian-kkp-keluhkan-milenial-tak-tertarik-bidang-
perikanan/ 117 Vol. 6, No. 2, www.jurnal.ugm.ac.id/jpkm
|
https://openalex.org/W4383196664
|
https://jurnal.ugm.ac.id/v3/sasdaya/article/download/8621/2932
|
Indonesian
| null |
Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi (Konflik dan Disharmoni Sosial di Yogyakarta Pada Pilpres tahun 2019)
|
Sasdaya
| 2,023
|
cc-by-sa
| 6,575
|
ABSTRACT Democracy that has lasted so far is not only understood as an effort to build a better government
system but is also intended as an effort to create citizen participation in building a good political and
governance system. But in reality, it does not produce a sense of security, peace, order and social
order. This paper is intended to look at the phenomenon of democracy, especially election practices,
not only from a political and power perspective, but also to see how elections actually create social
disharmony in the Yogyakarta city community. This paper is based on one argument, namely: that
democracy is intended to build a more open, just, peaceful and prosperous society that does not work
properly because the understanding and practices of democracy that have been practiced so far have
actually led to increased resistance and social disharmony. This paper uses a qualitative analytical
method with data sourced from direct observation and from local newspapers. From this research it
was found that (1) social conflict in villages, especially in Yogyakarta is getting higher and social
resistance is increasing; (2) Community grouping, and segregation tend to be based on religious and
political affiliations; and village gangs (3) Villages that used to be administratively separated, were
instead claimed as the village of certain groups which referred to certain religious-based groups or
parties. From this paper it can be concluded that the conflicts that occurred in the city of Yogyakarta
during the 2019 presidential election were more caused by village-based sentiments and solidarity of
certain parties and groups rather than conflicts between elites. Keyword: Democratization, social disharmony, social conflict, social solidarity EISSN 2549-3884
Email: sasdayajournal.fib@ugm.ac.id Disharmoni Sosial Masyarakat Kampung Kota
di Era Demokratisasi
(Konflik dan Disharmoni Sosial di Yogyakarta Pada Pilpres tahun 2019) Muhammad Arifin
Fakultas Ilmu Sosial dan Ilmu Politik, Universitas Mulawarman
Koresponden: muhammad.arifin@fisip.unmul.ac.id 59 | Muhammad Arifin PENDAHULUAN Demokrasi yang berlangsung selama ini tidak hanya dipahami sebagai upaya
membangun sistem pemerintahan yang lebih baik (Zuhro, 2019:70), akan tetapi juga
dimaksudkan sebagai upaya untuk menciptakan partisipasi warga (Sinaga, 2012:55;
Haliim, 2016:21) dalam membangun sistem politik dan pemerintahan yang baik. Esensi dari partisipasi adalah terciptanya rasa adil, kesejahteraan dan keteraturan
sosial, atau terciptanya masyarakat madani (Santoso, 2011:55). Namun dua puluh
tahun terakhir sejak reformasi tahun 1998, praktek demokrasi yang berjalan justru
tidak menghasilkan rasa aman, damai, ketertiban dan keteraturan sosial sebagaimana
diharapkan sebelumnya. Sebaliknya, eskalasi konflik (Surwandono, 20015), resistensi
dan disharmoni sosial, khususnya di kampung Kota Yogyakarta justru menunjukkan SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 SASDAYA SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 peningkatan yang signifikan. Berdasarkan penelusuran Masyarakat Anti Korupsi
Yogyakarta, konflik sosial berkaitan dengan praktek demokrasi (khususnya dalam
pilpres dan pilkada) sudah berlangsung lama, yaitu sejak tahun 1999, 2004, 2009, dan
2014. (https://nasional.tempo./read/7/04/2014). Bahkan berdasarkan informasi
yang dikutip dari laman https://mediaindonesia.com/read/22/02/2019 dan
https://jogja.tribunnews.com/2018/09/27 ditegaskan oleh Badan Pengawas Pemilu
(Bawaslu) Pusat bahwa Daerah Istimewa Yogyakarta (DIY) merupakan daerah rawan
konflik kedua di Indonesia setelah Papua Barat dengan indeks kerawanan 52,14 di
bawah Papua Barat yang menempati urutan pertama dengan persentase 52,83. Sejauh ini, studi tentang demokrasi sebagai konsep, cenderung melihat pada 3 aspek
secara mendasar. Pertama, demokrasi dilihat sebagai wacana global dan transnasional
(Dryzek, 2016; Dalhatu, 2019; O’Loughlin, 2016); Kedua, studi yang melihat
demokrasi sebagai bentuk pelembagaan kekuasaan, hegemoni dan manajemen
konflik ( Stokke, 2018); dan ketiga adalah melihat demokrasi dari sisi teori dan
konseptual (Cederman, dkk, 2008; Scholte, 2019; Welzel, 2006; Remmer, 2015;
Nugroho, 2012). Dari ketiga kecenderungan studi tersebut tampak bahwa studi
tentang dampak negatif dari praktek-praktek dan penyelenggaraan demokrasi, justru
bisa berdampak lahirnya konflik dan resistensi sosial, masih minim dilakukan. Berbagai studi yang pernah dilakukan berkaitan dengan fenomena konflik atau
kekerasan sebagaimana dipaparkan sudah ada yang pernah melakukan, misalnya
oleh CRCS (Center for Religious and Cross-cultural Studies) Universitas Gadjah Mada
tentang kekerasan minoritas di Yogyakarta (Ahnaf & Hairus Salim H. S., 2017);
Konflik dalam praktek demokrasi di arena kampus Unesa Tahun 2020 (Syafitri, dan
Sarwono, 2021) dan Konflik Pasca pemilihan kepala Desa Jembatan Merah di
Gorontalo tahun 2019 (Usman dan Marzaman (2019) dan beberapa konflik yang
terjadi pasca dan setelah pilkada dan Pilpres beberapa tahun yang lalu di beberapa
wilayah di Indonesia. Tulisan ini dimaksudkan untuk melengkapi kekurangan dari berbagai studi yang
cenderung melihat fenomena demokrasi, khususnya praktek pemilu dan pilkada
hanya dari sisi politik dan kekuasaan semata, atau berbagai tulisan yang hanya
melihat fenomena disharmoni sosial komunitas kota yang hanya dianggap sebagai
fenomena sosial ekonomi semata. Tulisan ini didasarkan pada satu argument, yaitu: bahwa demokrasi dimaksudkan
untuk membangun masyarakat yang lebih terbuka, adil, damai dan sejahtera tidak
berjalan semestinya karena pemahaman dan praktik-praktik demokrasi yang
dipraktikkan selama ini justru menyebabkan semakin meningkatkan resistensi dan
disharmoni sosial. Sebagai contoh; (1) Konflik sosial di kampung-kampung, SASDAYA SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 khususnya di Yogyakarta semakin tinggi dan meningkatnya resistensi sosial, padahal
dulunya dikenal sebagai masyarakat yang hidup damai, guyub dan harmonis; (2)
Pengelompokan dan segregasi masyarakat cenderung berbasis afiliasi agama dan
politik, yang sebelumnya hidup rukun dalam ikatan tradisi, kalaupun ada klaim
hanya sebatas klaim kelompok pemuda atau geng; (3) Kampung-kampung yang
dulunya terpisah secara administrasi, justru diklaim sebagai kampung kelompok
tertentu yang merujuk pada kelompok berbasis keagamaan atau partai tertentu. khususnya di Yogyakarta semakin tinggi dan meningkatnya resistensi sosial, padahal
dulunya dikenal sebagai masyarakat yang hidup damai, guyub dan harmonis; (2)
Pengelompokan dan segregasi masyarakat cenderung berbasis afiliasi agama dan
politik, yang sebelumnya hidup rukun dalam ikatan tradisi, kalaupun ada klaim
hanya sebatas klaim kelompok pemuda atau geng; (3) Kampung-kampung yang
dulunya terpisah secara administrasi, justru diklaim sebagai kampung kelompok
tertentu yang merujuk pada kelompok berbasis keagamaan atau partai tertentu. Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … | 6 61 | Muhammad Arifin METODE PENELITIAN Penelitian ini menggunakan metode kualitatif analitik dengan penekanan sumber
data lebih banyak pada hasil pengamatan langsung selama pelaksanaan dan setelah
pelaksanaan pilpres 2019 dan analisis berita dari media koran lokal yang memuat
berita tentang konflik dan resistensi yang terjadi selama pelaksanaan pilpres di
Yogyakarta tahun 2019. Pada konteks ini, wacana yang terbentuk selama periode
pilpres penulis melihatnya sebagai sebuah fenomena demokratisasi yang justru tidak
menciptakan suasana yang harmonis dan demokratis. Demokratisasi merupakan proses dinamis dengan banyak ancaman umum yang
membutuhkan kewaspadaan dan adaptasi secara terus-menerus (Goodman, 2021). Ada dua definisi demokrasi yang diutarakan oleh Mundt (2018), yakni “limited
government or some minimal level of pluralism”. Bagi penguasa/petahana, selalu ada
banyak alasan bagus mengapa demokratisasi “tidak sesuai dengan kepentingan
bangsa saat ini” (Mundt, 2018). Dasar pemikiran ini benar-benar berlaku bagi banyak
pengamat karena demokrasi seringkali (dan mungkin secara definisi) diasosiasikan
dengan ketidakpastian dan ketidakstabilan (Mundt, 2018). Untuk alasan apa pun,
demokratisasi pada umumnya merupakan produk dari kegagalan rezim otoriter
untuk mempertahankan kontrol yang efektif, ia biasanya tumbuh dari situasi di mana
tidak satu pun dari beberapa elit yang bersaing memiliki sumber daya untuk
mencapai kendali penuh, dan di mana kesepakatan untuk membatasi dan berbagi
adalah pilihan terbaik yang tersedia bagi para pesaing yang secara kolektif dapat
memaksakan tatanan baru (Mundt, 2018). Singkatnya, demokratisasi tumbuh dari
erosi kekuasaan dan kebuntuan (Mundt, 2018). Demokratisasi difasilitasi oleh kesepakatan regional dan stabilitas ekonomi, politik,
dan sosial (Goodman, 2021). Lebih khusus lagi, ada studi menarik yang dilakukan
oleh Goryacheva (2016) yakni tentang demokratisasi media yang tengah menjadi
topik hangat di hampir semua negara di Amerika Selatan. Di negara-negara tersebut,
tuntutan reformasi dan konflik politik muncul karena ketidaksesuaian antara media
massa yang terkonsentrasi, komersial, dan seringkali konservatif di satu sisi, dan
posisi politik pemerintah kiri-tengah serta tuntutan sosial untuk demokrasi 60 SASDAYA https://doi.org/10.22146/sasdaya.8621 Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 SASDAYA https://doi.org/10.22146/sasdaya.8621 Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 partisipatif di sisi lain (Goryacheva, 2016). Akhirnya, studi yang dilakukan oleh
Goryacheva (2016) menemukan bahwa perjuangan atas demokratisasi media berakar
pada perkembangan sosial dan politik yang lebih besar termasuk pergeseran
kekuasaan yang konfliktual. Realitasnya dalam praktek demokrasi selama, justru sering menimbulkan konflik dan
disharmoni sosial. Studi disharmoni sosial banyak yang berlatar belakang kehidupan
keberagaman sebagaimana penelitian yang dilakukan oleh Walsh et al. (2020), Howie
et al. (2021), Keddie (2014) dan Westerlund et al. (2022). Disharmoni sosial ini
mencakup saat-saat perebutan identitas (Berglund and Schwartz, 2013). Di dalamnya,
ada hambatan integrasi antar masyarakat. Menurut Alaverdov (2021), perbedaan
lingkungan budaya dan agama yang kuat dan mengakar menjadi hambatan serius
bagi integrasi sosial. Selain itu, ada penyebab lain ketidakharmonisan, yakni
ketidakkonsistenan dalam pelaksanaan norma dan aturan, ketidaksamaan
paradigma, juga karena pola kepemimpinan otoriter (Iska et al., 2022). Rennuy (2019)
pun menyatakan bahwa ketidakharmonisan diakibatkan oleh keterlibatan beberapa
tatanan hukum yang tidak dapat disesuaikan. Sementara itu, Bannister and
O’Sullivan (2013) lebih melihat ketiadaan atau kerusakan hubungan masyarakat
sebagai penyebab ketidakharmonisan sosial yang disebut oleh Gupta, Sharma and
Gupta (2021) dan Westerlund et al. (2022) dapat mengarah juga pada konflik di ranah
keluarga dan masyarakat pada tingkat yang lebih lanjut. Oleh karena itu, tantangan
utama bagi kebijakan adalah peningkatan kualitas hubungan masyarakat (Bannister
and O’Sullivan, 2013). Ketidakharmonisan tidak ada begitu saja, akan tetapi ada hal-hal lain yang biasanya
mengiringi ketidakharmonisan sosial antara lain perang dan kekerasan, ekstremisme
dan terorisme, dan/atau politik publik yang bermusuhan (Howie et al., 2021). Di Uni
Emirat Arab (UEA), ketidakharmonisan sosial diawali oleh struktur demografis yang
tidak stabil dan tidak seimbang sehingga menciptakan dominasi budaya (Al Oraimi,
2020). Semua keadaan ini selain berpengaruh terhadap keharmonisan komunal, juga
terhadap kohesi sosial dan interaksi sosial langsung dari kelompok budaya yang
mengarah pada ketegangan dan ketidaknyamanan di negara tersebut (Al Oraimi,
2020). Dalam studi lain, Howie et al. (2021) menawarkan suatu solusi atas adanya
disharmoni sosial, yakni dengan merangkul perbedaan yang ada. Sementara itu,
Bannister and O’Sullivan (2013) secara khusus mengusulkan bahwa koeksistensi
damai dari berbagai kelompok sosial bertumpu pada keberadaan dan pemeliharaan
empati antar-kelompok dan saling menghormati. Intensitas Konflik Sosial Meningkat Intensitas Konflik Sosial Meningkat Muncul berbagai kekhawatiran warga Yogyakarta setiap kali menjelang pesta
demokrasi. Baik pada tingkat lokal berupa pemilihan kepala daerah (pilkada),
maupun dalam skala nasional dengan pemilihan presiden (pilpres). Kekhawatiran
ini sangatlah beralasan sebab setiap kali pelaksanaan pesta demokrasi tersebut,
berbagai benturan fisik, ataupun resistensi sosial antara para pendukung calon
ataupun simpatisan partai selalu terjadi. Bahkan di luar dari kegiatan pesta
demokrasi, gesekan-gesekan pun juga seringkali berlangsung hingga ke kampung-
kampung dalam kota Yogyakarta dengan mengakibatkan adanya korban dan
kerugian material. Informasi yang didapatkan lewat media online menunjukkan bahwa konflik atau
ketegangan sosial terus berlangsung saat berlangsungnya pilkada dan pilpres di Kota
Yogyakarta dan sekitarnya dari tahun 2004 hingga tahun 2019, sebagaimana
ditunjukkan pada tabel 1 berikut ini : Tabel 1 Intensitas, Skala dan Frekuensi Konflik selama Pelaksanaan Kampanye Pilpres di
Yogyakarta
Tahun
Jenis kejadian
Skala Konflik
Intensitas
Korban/
Kerugian
Material
Sumber
2004
Bentrokan Massa
PDI dgn Warga
kampung
Meluas ke
beberapa
kampung di kota
hingga ke Bantul
4 kali
2 Korban luka
4 motor rusak
https://nasional.tempo. co/
read/40708/bawa-
pedang-dan-clurit-
massa-pdip-
ditahan/16/03/2004
2009
Peristiwa
bentrokan antara
massa PDIP dan
PPP di sekitar
Pojok Beteng
Wetan
dilokalisir
1 kali
Tdk ada
https://nasional.tempo. co/
read/568493/bentrok-
pendukung-partai-
langganan-pemilu-di-
yogya
2014
Bentrok kampanye
antara PPP dengan
PDIP tanggal 5
April 2014. Dikeroyok Ormas,
Lima Motor
Simpatisan Partai
Dirusak, 5 April
2014
Lokasi konflik di
parkir Ngabean,
Krapyak,
Jogokaryan, ring
road selatan
menuju ke
Krapyak.)
Lokasi: terjadi di
Ngabean,
Ngampilan, Kota
5 kali
5 motor
http://www.tribunnew
s.com/2014/04/06/;
(https://daerah.sindone
ws.com/read/876711/2
2/
https://www.merdeka. com/peristiwa/26/06/
2014 1 Intensitas, Skala dan Frekuensi Konflik selama Pelaksanaan Kampanye Pilpres di
Yogyakarta Tabel 1 Intensitas, Skala dan Frekuensi Konflik selama Pelaksanaan Kampanye Pilpres Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … | 62 Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … | 62 62 63 | Muhammad Arifin SASDAYA SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023
https://doi.org/10.22146/sasdaya.8621
Bentrokan antara
massa PDIP dan
massa PPP Di sisi
utara jalan
merupakan basis
massa PDIP, di sisi
selatan merupakan
basis massa dari
PPP (tanggal 4 Juni
2014)
Yogyakarta. Lokasi konflik di
Jalan Letjen
Suprapto. 2019
Dirilis Polda DIY,
beberapa
diantaranya al:
Bentrokan Massa
Pendukung PPP
dan PDIP saat
kampanye
Kericuhan yang
terjadi di Masjid
Jogokariyan antara
masyarakat
setempat dan
massa PDIP pada
Minggu
(27/1/2018)
Bentrok antara
parpol peserta
Pemilu 2019 itu
terjadi pada
Minggu
(23/12/2018)
Bentrok antara
massa PDIP vs PPP
Kericuhan yang
terjadi antara kubu
PDIP dan PPP di
Yogyakarta pada
Minggu
(27/1/2019)
Konflik antara
pendukung
Prabowo Subianto
dengan pendukung
Jokowi (khususnya
PDIP dan PPP
(GPK) (27/2/2019). Ketegangan
selama kampanye
di Yogyakarta dan
sekitarnya
Meluas ke
Bantul dan
Sleman
Meluas ke
kampung lainnya
dan muncul
sentiment agama
di Bantul dan
Yogyakarta. Dusun Jetak, Desa
Ringinharjo,
Bantul
Ngabean/Ngamp
ilan dan
sekitarnya
Yogyakarta &
Sleman
17 kali
13 luka
1 kritis
5 motor rusak
1 mbl
terbakar
3 mobil rusak
Perusakan
kantor Rama
sakti
5 rumah
dirusak
https://tirto.id/dhXJ. https://www.beritasatu
.com/nasional/ 29/01/
2019
https://tirto.id/dfim
https://pojoksatu.id/ne
ws/berita-
nasional/2018/12/24
https://www.gatra.com
/;
https://radarjogja.co/2
019/01/28/bentrok-
kembali-pecah-di-
ngabean/
https://tirto.id/respons
-ppp-khittah-pdip-soal-
ricuh-kedatangan-
prabowo-di-yogya-dhXJ
Sumber : Pengolahan Data sekunder Tahun 2022 Sumber : Pengolahan Data sekunder Tahun 2022 63 | Muhammad Arifin Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … | 64 SASDAYA SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 Berdasarkan tabel 1, tampak bahwa terjadi peningkatan jumlah kasus ketegangan
atau gesekan antara simpatisan partai politik selama periode penyelenggaraan
pilkada dan pilpres. Ketegangan ini berdasarkan catatan media mainstream sudah
berlangsung sejak lama, yaitu berawal sekitar tahun 1999 setelah era reformasi,
khususnya ketegangan antara Partai Persatuan pembangunan (PPP) dengan Partai
Demokrasi Indonesia Perjuangan (PDIP). Bahkan dalam laporan Polda DIY, terjadi
peningkatan signifikan terjadi pada tahun 2019, yaitu sebanyak 17 kasus ketegangan
yang sebelumnya hanya 5 kasus. Intensitas ketegangan ini seiring dengan
meningkatnya eskalasi ketegangan yang sebelumnya hanya terfokus pada satu lokasi
saja, sementara pada tahun 2019 makin meluas ke beberapa kampung kota
Yogyakarta hingga ke kampung-kampung lainnya di Kabupaten Bantul dan
Kabupaten Sleman. Demikian halnya jumlah korban luka dan kerugian material juga
mengalami peningkatan di tahun yang sama. Khusus peningkatan jumlah
ketegangan sosial dimaksud terlihat secara jelas pada chart 1 berikut: Grafik 1. Peningkatan Intensitas Konflik Sosial berbasis Partai di Kota Yogyakarta
(Sumber: Pengolahan data sekunder tahun 2022)
4
1
5
17
2004
2009
2014
2019
Trend Perkembangan Ketegangan Sosial Selama
periode Kampanye Pilpres di Yogyakarta Trend Perkembangan Ketegangan Sosial Selama
periode Kampanye Pilpres di Yogyakarta Grafik 1. Peningkatan Intensitas Konflik Sosial berbasis Partai di Kota Yogyakarta
(Sumber: Pengolahan data sekunder tahun 2022) Semakin meningkatnya intensitas, eskalasi dan jumlah korban serta kerugian pada
periode pemilihan presiden tahun 2019 di Yogyakarta sebagaimana ditunjukkan pada
tabel 1 dan chart 1 di atas sejak awal sudah diprediksi oleh berbagai kalangan. Berbagai indikasi, diantaranya pertama, meningkatnya intensitas dan luasnya
eskalasi konflik di Yogyakarta sudah berlangsung sejak lama, dan selalu terjadi hanya
pada dua kelompok pendukung partai saja. Kedua, adalah lahirnya berbagai
kelompok-kelompok berafiliasi keagamaan (Islam) di Yogyakarta dengan berbagai
gerakan-gerakan yang seringkali dicap sebagai gerakan radikal. Ketiga, Kota
Yogyakarta merupakan basis Partai Islam, PAN dan PPP dengan sejumlah saya
partainya, yaitu GPK, AMK dan HAMKA serta FUI, demikian pula dengan Partai
Demokrasi Indonesia Perjuangan (PDIP). Ketiga indikasi ini terus menunjukkan Semakin meningkatnya intensitas, eskalasi dan jumlah korban serta kerugian pada
periode pemilihan presiden tahun 2019 di Yogyakarta sebagaimana ditunjukkan pada
tabel 1 dan chart 1 di atas sejak awal sudah diprediksi oleh berbagai kalangan. Berbagai indikasi, diantaranya pertama, meningkatnya intensitas dan luasnya
eskalasi konflik di Yogyakarta sudah berlangsung sejak lama, dan selalu terjadi hanya
pada dua kelompok pendukung partai saja. 65 | Muhammad Arifin SASDAYA Kedua, adalah lahirnya berbagai
kelompok-kelompok berafiliasi keagamaan (Islam) di Yogyakarta dengan berbagai
gerakan-gerakan yang seringkali dicap sebagai gerakan radikal. Ketiga, Kota
Yogyakarta merupakan basis Partai Islam, PAN dan PPP dengan sejumlah saya
partainya, yaitu GPK, AMK dan HAMKA serta FUI, demikian pula dengan Partai
Demokrasi Indonesia Perjuangan (PDIP). Ketiga indikasi ini terus menunjukkan 64 SASDAYA SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 peningkatan yang sig bahkan di luar aktivitas kampanye, sehingga ada kemungkinan
tahun-tahun berikutnya akan mengalami peningkatan lagi Pengelompokan sosial berbasis agama dan politik SASDAYA SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 kelompok partai pendukung partai, yaitu Partai persatuan Pembangunan (PPP) yang
disebut sebagai partai atau “laskar Ijo” dan Partai Demokrasi Indonesia Perjuangan
(PDIP) yang disebut sebagai partai atau “laskar Abang”. Dari 20 ruas jalan raya yang
diamati dalam Kota Yogyakarta sebagaimana terlihat pada tabel 2 masing-masing 10
diantaranya merupakan ruas jalan dikuasai oleh masing-masing partai berdasarkan
keberadaan secara dominan bendera partai masing-masing. kelompok partai pendukung partai, yaitu Partai persatuan Pembangunan (PPP) yang
disebut sebagai partai atau “laskar Ijo” dan Partai Demokrasi Indonesia Perjuangan
(PDIP) yang disebut sebagai partai atau “laskar Abang”. Dari 20 ruas jalan raya yang
diamati dalam Kota Yogyakarta sebagaimana terlihat pada tabel 2 masing-masing 10
diantaranya merupakan ruas jalan dikuasai oleh masing-masing partai berdasarkan
keberadaan secara dominan bendera partai masing-masing. Penguasaan ruang-ruang publik berupa jalan raya berdasarkan pengamatan selama
musim kampanye pilkada dan pilpres, semakin menegaskan bahwa jalan raya adalah
ruang utama dimana intensitas konflik dan ketegangan terjadi, khususnya saat
berlangsungnya aktivitas kampanye yang memobilisasi massa simpatisan partai
dengan menggunakan kendaraan bermotor, baik roda dua maupun roda empat. Yang
menarik dari fenomena penguasaan ruang-ruang publik berupa ruas jalan raya
adalah telah disepakatinya sebuah ikrar bersama sejak tahun 1999 antara petinggi
partai dengan pihak kepolisian untuk tidak melewati ruas-ruas jalan tertentu yang
menjadi basis masing-masing partai. Sebagaimana pernyataan sesepuh Masjid
Jogokaryan yang dimuat dalam Koran Tempo (28/01/2019) sebagai berikut: “Padahal sejak pemilu tahun 1999, sudah ada kesepakatan dari Kapolda DIY saat
itu, bahwa massa PDIP di larang konvoi di area Jogokariyan, kok sekarang bisa
masuk ? . “Simpatisan PDIP dan PPP sendiri selama ini di Yogya tak pernah akur
dan kerap terlibat ricuh, terlebih saat masa kampanye pemilu. Zona massa PDIP
dan PPP pun dibagi berdasarkan warna dominan partai itu, yakni zona merah dan
zona hijau. “Nah, ini kok mereka (massa konvoi PDIP) bisa masuk zona hijau, apa
sudah ada perubahan kebijakan?” (https://nasional.tempo.co/read/) Adanya penguasaan ruang, khususnya ruas jalan di Kota Yogyakarta memang
menjadi problem utama dalam menjaga kondusifitas selama berlangsungnya
kampanye karena basis-basis massa seringkali tidak bisa dikontrol. Berdasarkan
kondisi obyektif ini pihak kepolisian mengambil langkah preventif untuk mengatasi
ketegangan dimaksudkan dengan melakukan pengamanan dengan menempatkan
personil pada titik-titik singgungan yang menjadi zona penguasaan masing-masing
simpatisan partai. Pengelompokan sosial berbasis agama dan politik Yogyakarta adalah sebuah gambaran bagaimana ruang-ruang kota yang bersifat
publik telah dibagi ke dalam berbagai ruang-ruang private dengan afiliasi politik atau
berbasis kelompok politik tertentu. Khususnya pada ruang publik jalan raya dalam
kota Yogyakarta, pembagian dan penguasaan ruang-ruang terlihat dari banyaknya
atau dominasi bendera partai di sepanjang jalan tersebut. Hal ini sangat tampak saat
menjelang pelaksanaan pemilihan kepala daerah maupun pemilihan presiden
sebagaimana telah berlangsung selama beberapa tahun belakangan. Hasil
pengamatan penulis menunjukkan fakta-fakta sebagaimana terlampir pada tabel 2
berikut: Tabel 2 Penguasaan Jalan Raya berbasis Partai Politik dalam Kampanye Pilpres 2019. No
Pembagian Ruang /Jalan Raya Berdasarkan Kelompok/Aliran/Politik/Agama
Laskar IJO (PPP)
Laskar Abang (PDIP)
1
JL. Kauman
JL. Mataram
2
JL. KH. Ahmad Dahlan
JL. Wijilan
3
JL. Nyi Ahmad Dahlan
JL. Suryoputran
4
JL. K.H. Wahid Hasyim
JL. Panembahan Mangkurat
5
JL. S. Parman
JL. Panembahan Senopati
6
JL. Mayjen Sutoyo
JL. S. Parman
7
JL. Ibu Ruswo
JL. Ireda
8
JL. Urip Sumoharjo
JL. Suharto
9
JL. K.H Agus Salim
JL. Juminahan
10
JL. Ngasem
JL. Suprapto
Sumber: Hasil Pengamatan Penulis Tahun 2022 Tabel 2 Penguasaan Jalan Raya berbasis Partai Politik dalam Kampanye Pilpres 2019. Table 2 menunjukkan bagaimana jalanan di Kota Yogyakarta sebagai ruang publik
telah berubah menjadi ruang atau jalanan yang private, meskipun sifatnya temporer
yaitu pada saat kampanye saja. Hasil penelusuran dan pengamatan menunjukkan
bahwa ruas-ruas jalanan tertentu di Kota Yogyakarta telah dikuasai berdasarkan dua Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … 67 | Muhammad Arifin SASDAYA SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 (https://kumparan.com/kumparannews/polisi-petakan-daerah-rawan-konflik-
di-yogya-jelang-kampanye)” (https://kumparan.com/kumparannews/polisi-petakan-daerah-rawan-konflik-
di-yogya-jelang-kampanye)” (https://kumparan.com/kumparannews/polisi-petakan-daerah-rawan-konflik-
di-yogya-jelang-kampanye)” Jika mencermati fenomena penguasaan ruang-ruang sebagaimana dipaparkan,
tampak bahwa ruang publik Yogyakarta bukanlah ruang yang aman dan bebas, tetapi
telah menjadi ruang politik yang tidak aman karena telah menjadi arena konflik
kepentingan antara berbagai kelompok atau partai politik yang hingga sekarang
terus berlanjut. SASDAYA Sebagaimana ditegaskan oleh Kapolresta Kota Yogyakarta yang
dimuat dalam media online sebagai berikut: “"Kita sudah lakukan pemetaan daerah-daerah rawan konflik terkait dengan
pemilu. Di Yogya ini rawan konflik, gesekan antara laskar-laskar hijau dengan
laskar-laskar merah. Kami juga telah melakukan pemetaan pengamanan pemilu
di Kota Gudeg. Pemetaan itu khususnya menjelang jadwal kampanye akbar yang
dimulai pada 24 Maret hingga 13 April. Beberapa titik ada di Ngabean titik
singgung antara basis hijau (PPP) dan merah (PDI Perjuangan). Daerah
Jogokariyan kita juga petakan pernah terjadi konflik kan di situ. Kemudian daerah
Warungboto itu daerah basis. Kita sudah letakkan (personil) berdasarkan peta ini
ketika melakukan pengamanan. Kita bisa atur jalurnya apakah merah atau hijau
nanti
mau
lewat
kita
atur
jalan
yang
aman,”
kata
dia. “"Kita sudah lakukan pemetaan daerah-daerah rawan konflik terkait dengan
pemilu. Di Yogya ini rawan konflik, gesekan antara laskar-laskar hijau dengan
laskar-laskar merah. Kami juga telah melakukan pemetaan pengamanan pemilu
di Kota Gudeg. Pemetaan itu khususnya menjelang jadwal kampanye akbar yang
dimulai pada 24 Maret hingga 13 April. Beberapa titik ada di Ngabean titik
singgung antara basis hijau (PPP) dan merah (PDI Perjuangan). Daerah
Jogokariyan kita juga petakan pernah terjadi konflik kan di situ. Kemudian daerah
Warungboto itu daerah basis. Kita sudah letakkan (personil) berdasarkan peta ini
ketika melakukan pengamanan. Kita bisa atur jalurnya apakah merah atau hijau
nanti
mau
lewat
kita
atur
jalan
yang
aman,”
kata
dia. 66 SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023
https://doi.org/10.22146/sasdaya.8621
(https://kumparan.com/kumparannews/polisi-petakan-daerah-rawan-konflik-
di-yogya-jelang-kampanye)” SASDAYA https://doi.org/10.22146/sasdaya.8621 meresahkan masyarakat karena berbagai tindakan brutal yang dilakukannya,
meskipun dengan dalih agama. Demikian halnya dengan Joxin, merupakan
kelompok pemuda legendaris yang dikonotasikan sebagai basis preman dan
berkonsentrasi di Kampung Kauman. Secara historis, Joxin memang dikenal sebagai
komunitas preman, namun sekarang telah bertransformasi menjadi organisasi sayap
PPP yang berbasis agama. Demikian halnya dengan beberapa organisasi sayap PDIP,
seperti tentara langit adalah organisasi sayap partai yang selama ini seringkali
melakukan aktivitas kampanye dengan mobilitas massa yang banyak dan terkadang
brutal. Masing-masing kubu dari kedua partai dalam realitasnya seringkali menggunakan
jargon-jargon agama dan ideologi dan agama dalam berkampanye dimana organisasi
saya merupakan ujung tombak dalam melakukan mobilisasi massa secara besar-
besaran. Dalam banyak kasus, organisasi sayap seringkali menjadi dalang dari setiap
ketegangan yang terjadi di antara mereka. Bahkan dengan masyarakat di beberapa
kampung di Yogyakarta seringkali berhadapan dengan organisasi saya masing-
masing partai ini, tergantung konsentrasi basis-basis simpatisan mana yang mereka
datangi atau lalui. Fenomena perkembangan organisasi sayap partai, sebagaimana
terlihat pada tabel 3, mengindikasikan adanya kecenderungan semakin kuatnya
soliditas partai, sebaliknya bisa juga mengindikasikan semakin tinggi dan kuatnya
ketegangan dan resistensi sosial warga kampung kota di Yogyakarta. Jika mencermati perkembangan ketegangan dan disharmonis sosial yang terjadi
selama ini di Kota Yogyakarta, baik saat hari-hari biasa, dan secara khusus pada
musim kampanye dapat dibaca sebagai sebuah upaya kedua kubu membangun
eksistensi dan identitasnya masing-masing. Namun pada saat yang sama justru
menunjukkan akan semakin kuat dan tingginya resistensi, ketegangan dan kekerasan
di level kampung Kota Yogyakarta. Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … | 6 Penguatan Kelompok Berafiliasi Partai di Yogyakarta Tahun 2019 Penguatan Kelompok Berafiliasi Partai di Yogyakarta Tahun 2019 Seiring semakin terbukanya keran kebebasan berorganisasi, maka perkembangan
organisasi sosial kemasyarakatan juga semakin mengalami peningkatan. Khususnya
organisasi sosial berbasis/berafiliasi politik. Bahkan berdirinya beberapa partai baru,
juga diiringi oleh muncul/dibentuknya organisasi sayap partai. Bertambah dan
meningkatnya jumlah organisasi saya partai mengindikasikan soliditas masyarakat
kota berbasis politik. Sebagaimana ditunjukkan pada tabel 3 berikut. Tabel 3 Penguatan Organisasi Sosial Berbasis Agama dan Politik
No
Organisasi Kemasyarakatan Berafiliasi Partai Politik
PPP
PDIP
1
GPK
Tentara langit
2
HAMKA Kauman/Hamka Darwis
Barisan Muda Indonesia
3
AMK (Angkatan Muda Ka’bah)
Taruna Merah Putih
4
HMK (Himpunan Muda Ka’bah)
Aliansi Masyarakat Yogyakarta
5
BMK (Barisan Muda Ka’bah)
Laskar Banteng Yogya
6
Joxin
Aliansi Lascar Banteng
7
Forum Ummat Islam
Laskar Randu Alas
8
Muslim Green Zone
Laskar Bajuningrat
Sumber: http://www.indojayanews.com/27/01/2022; https://jogja.tribunnews.com/2014/04/06/ Tabel 3 Penguatan Organisasi Sosial Berbasis Agama dan Politik http://www.indojayanews.com/27/01/2022; https://jogja.tribunnews.com/2014/04/06/ Tabel 3 di atas menunjukkan bahwa baik Partai Persatuan Pembangunan (PPP)
maupun Partai Demokrasi Indonesia Perjuangan (PDIP) masing-masing memiliki
organisasi sayap yang selama ini sudah dikenal dengan baik oleh warga Yogyakarta. Organisasi seperti Gerakan Pemuda Ka’bah (GPK) dan FUI misalnya adalah saya PPP
yang sudah dicap sebagai organisasi sayap yang radikal dan dianggap seringkali SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 69 | Muhammad Arifin SASDAYA
G https://doi.org/10.22146/sasdaya.8621 Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 ‘menunggangi’ acara muslim United. Hal tersebut dikarenakan adanya beberapa
tokoh dalam acara tersebut yang dirumorkan mempunyai afiliasi dengan HTI. Seperti
twitter yang ditulis oleh Gun Romli seorang politisi muda PSI dalam twitternya yang
dimuat dalam geotimes.co.id sebagai berikut: ‘’Sudah benar @Keratonjogja tidak memberikan izin pada Muslim United untuk
menggelar acara di Masjid Gedhe Kauman karena acara ini sudah ditunggangi oleh
pendukung Khilafah ala Hizbut Tahrir Indonesia (HTI)” Atas dasar kecurigaan tersebut, kegiatan ini ditolak dilaksanakan di Masjid Gedhe
Kauman oleh pihak keraton sebagai pemilik masjid. Bahkan upaya pembubaran pada
pelaksanaan hari pertama melalui negosiasi pihak polda DIY yang diwakili oleh
Kapolda. (https://geotimes.co.id/opini/penolakan-acara-muslim-united-dan-upaya-deradikalisasi/) Terlepas dari penerimaan dan penolakan berbagai kelompok, akan tetapi aktivitas ini
merupakan aktivitas yang khusus dan spesifik ditujukan kepada umat Islam dari
kelompok tertentu saja. Aktivitas yang eksklusif/khusus Aktivitas yang eksklusif/khusus Polarisasi sosial masyarakat, tidak hanya tampak dari beragamnya kelompok atau
organisasi kepentingan, akan tetapi juga ditandai oleh semakin spesifiknya berbagai
aktivitas atau kegiatan kelompok masyarakat bersangkutan. Warga kampung kota
Yogyakarta yang terpolarisasi berdasarkan kelompok partai, dan organisasi
kepentingan lainnya, juga diiringi oleh aktivitas yang mencirikan dan menegaskan
identitas kelompok masing-masing. Beberapa aktivitas spesifik dimaksudkan adalah
sebagai berikut: Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi 68 SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 1. Muslim United 1. Muslim United
Gambar 1. Contoh Poster Aktivitas dari Kelompok Masyarakat dengan Identitas Tertentu
(Sumber: https://www.kompasiana.com/ibnujalilalindonesia) Gambar 1. Contoh Poster Aktivitas dari Kelompok Masyarakat dengan Identitas Tertentu
(Sumber: https://www.kompasiana.com/ibnujalilalindonesia) Muslim United (MU) adalah kegiatan yang berisi dakwah, bazaar dan aktivitas
ekonomi lainnya yang diselenggarakan oleh Forum Ukhuwah Islamiyah (FUI) dan
Takmir Masjid Gedhe Kauman. Kegiatan ini telah dilakukan sebanyak dua kali, yaitu
tahun 2018 dan tahun 2019. Pada kegiatan pertama, tagline yang diusung adalah
“MUSLIM UNITED DAY #1 JALAN TERUS DIJALAN YANG LURUS ( ISTIQOMAH
DALAM ISLAM ). Bahkan di Facebook panitia MU 1 terpampang gambar dengan tulisan
“Jogja kota Hidayah”, seperti pada gambar berikut ini: Gambar 2. Contoh Leaflet Muslim United
(Sumber: Laman Facebook MU 1, 2019) Gambar 2. Contoh Leaflet Muslim United
(Sumber: Laman Facebook MU 1, 2019) Pada pelaksana Muslim United (MU) kedua, mengusung tagline “tagline #Sedulur
Saklawase” dengan falsafah luhur dari sultan Hamengkubuwono I, yaitu Nyawiji
(menyatu), greget (penuh semangat), sengguh (percaya diri), ora mingkuh (penuh
tanggung jawab). Baik MU 1 maupun MU 2 keduanya dimaksudkan sebagai upaya
menggalang persatuan ummat Islam dari berbagai penjuru. Meskipun dimaksudkan
sebagai upaya membangun solidaritas umat Islam, akan tetapi yang tampak dari
aktivitas ini, khususnya Muslim United 2 adalah sebuah gerakan yang ditengarai oleh
berbagai pihak sebagai kegiatan kampanye atau gerakan penolakan terhadap
kelompok tertentu. Terlebih dilaksanakan saat menjelang pelantikan presiden
terpilih. Selain alasan itu adanya isu lain tentang adanya kelompok HTI yang Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … | 70 71 | Muhammad Arifin 2. Dangdut Dangdut sebagai sebuah seni merujuk pada jenis/gendre music khas yang sudah
merakyat. Bahkan dalam berbagai acara formal dan informal di kampung-kampung
ataupun di kota, dangdut merupakan gendre music yang paling populer dan
digandrungi oleh masyarakat kebanyakan. Khususnya dalam kegiatan kampanye,
lagu dangdut atau “dangdutan” merupakan instrumen khusus yang sering
digunakan sebagai penarik/mobilitas massa. Oleh karena itu, dangdutan seringkali
dikonotasikan dengan sebuah pesta yang semarak dan riuh, atau dengan kelas atau
identitas sosial tertentu. Dalam hal ini, dangdut merepresentasikan identitas
kelompok tertentu. Khusus pesta dangdut yang dilakukan oleh sekelompok masyarakat di alun-alun
utara pada tanggal 5-6 Oktober 2019, dalam pandangan kelompok Islam para
pendukung pasangan 02 atau kelompok Islam yang tergabung dalam Muslim United
merupakan kegiatan yang secara khusus dilakukan oleh para pendukung pasangan
01. Klaim ini terlihat dari adanya pengecualian/perbedaan perlakukan kebijakan dari
kedua kegiatan tersebut. Tampak pada gambar berikut ini: Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 h Mada Journal of Humanities, Vol. 7. No. 1, 2023 Gambar 3. Persaingan Acara Massal yang Bersifat Religius dan Pestapora
(Sumber: https://www.google.com/search?safe) Gambar 3. Persaingan Acara Massal yang Bersifat Religius dan Pestapora
(Sumber: https://www.google.com/search?safe) 3. Eksklusifitas Kampung-Kampung Kota Yogyakarta 3. Eksklusifitas Kampung-Kampung Kota Yogyakarta SASDAYA SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 Berdasarkan penelusuran atau pengamatan di beberapa kampung kota Yogyakarta
berdasarkan umbul-umbul dan logo partai yang dominan, tampak bahwa basis-basis
massa secara tegas terlihat. Kampung dengan label partai (PPP) atau kampung Ijo
meliputi kampung yang menjadi basis Muhammadiyah. Misalnya Kampung
Kauman, Notoprajan, Karangkajen, dan Jogokaryan. Sebaliknya kampung-kampung
yang dikategorikan sebagai kampung PDIP atau kampung abang adalah kampung
yang selama ini dikenal sebagai kampung Kejawen, diantaranya adalah kampung
Ngampilan, Tegal kemuning, Kampung Ledok, Rotowijayan dan wilayah Keraton. Labeling Kampung berafiliasi Tokoh. 3. Eksklusifitas Kampung-Kampung Kota Yogyakarta Penguasaan ruang-ruang kota di Yogyakarta bukan saja penguasaan ruas-ruas jalan,
akan tetapi juga penguasaan perkampungan yang bahkan secara eksklusif
dikategorikan sebagai kampung berbasis agama, aliran dan politik. Bahkan seringkali
kampung tersebut berasosiasi dengan tokoh politik tertentu Labeling Kampung Berdasarkan agama, aliran dan politik Tabel 4. Pembagian Kampung Kota Yogyakarta Berbasis Politik/Aliran dan Agama
No
Pembagian Ruang /Kampung Berdasarkan Kelompok/Aliran/Politik/Agama
Kampung Islam/Kampung PPP (Kampung
IJO)
Kampung
Kejawen/Kampung
PDIP
(Kampung Abang)
1
Kampung Kauman
Kampung Tegal Kemuning
2
Kampung Suronatan
Kampung Ledok
3
Kampung Karangkajen
Macasan
4
Ngabean
Ngampilan
5
Jogokaryan
Rotowijayan
6
Warungboto
Polowija
7
Gading
Keraton
Sumber: Hasil Survei Penulis 2022 Tabel 4. Pembagian Kampung Kota Yogyakarta Berbasis Politik/Aliran dan Agama Sumber: Hasil Survei Penulis 2022 Tabel 4 menggambarkan ruang kampung terpolarisasi dan diklaim sebagai ruang
politik dan agama, atau dikontraskan sebagai kampung ijo vs kampung merah. Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … | 72 1. Kampung Jokowi Kampung Jokowi adalah kampung yang diberi label oleh para pendukung Jokowi
saat pelaksanaan pilpres tahun 2019. Di jawa tengah, khususnya di Klaten dan Solo
labeling Jokowi terhadap kampung-kampung banyak ditemukan. Namun yang
tampak pada foto ini adalah salah satu kampung di Sidokarto Godean Sleman. Gambar 4. Labeling suatu daerah dengan atribut atau identitas tertentu 1
(Sumber: https://www.google.com/search) Gambar 4. Labeling suatu daerah dengan atribut atau identitas tertentu 1
(Sumber: https://www.google.com/search) Pemberian label ini tidak saja mengindikasikan sebuah dukungan politik, moral dan
bahkan material. Akan tetapi juga mengindikasikan sebuah klaim penguasaan sebuah
Kawasan kampung oleh kelompok pendukung berdasarkan partai politik tertentu. Bahkan labeling semacam ini sering dikuatkan dengan munculnya kampung relawan
para pasangan calon tertentu, misalnya kampung relawan pendukung Jokowi
(SAJOJO) seperti tampak pada gambar berikut. Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … https://doi.org/10.22146/sasdaya.8621 Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 Gambar 5. Labeling suatu daerah dengan atribut atau identitas tertentu 2
(Sumber: https://jogja.tribunnews.com/2018/07/23/) Gambar 5. Labeling suatu daerah dengan atribut atau identitas tertentu 2
(Sumber: https://jogja.tribunnews.com/2018/07/23/) 73 | Muhammad Arifin SASDAYA SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 signifikan. Khususnya periode tahun 2019 intensitas ketegangan mencapai 17 kali
dengan eskalasi yang meluas pula ke beberapa kampung di Kabupaten Bantul dan
Sleman. Meningkatnya intensitas dan eskalasi konflik serta ketegangan antara
kampung-kampung kota di Yogyakarta berimplikasi luas pada beberapa aspek
kehidupan sosial masyarakat kampung. Misalnya relasi sosial terputus, ketegangan
antar kelompok dan tetangga kampung, ketertiban sosial terganggu hingga kerugian
ekonomi. Penguasaan ruang-ruang public perkotaan di Yogyakarta tidak hanya
mencakup penguasaan ruas-ruas jalan utama di dalam kota, akan tetapi juga
penguasaan rang-ruang beberapa perkampungan berbasis partai politik, aliran dan
bahkan agama. Penguasaan ini mencakup penguasaan lahan parkir dan area untuk
aktivitas kampanye. Bahkan telah diklaim sebagai kawasan private kelompok atau
partai tertentu. Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … | 74 KESIMPULAN Wacana demokrasi yang dipraktekkan selama ini adalah wacana global yang selalu
melekat dan terkait dengan praktek-praktek politik dan kekuasaan. Salah satu
fenomena yang seringkali dan rutin dilakukan sebagai bagian dari praktek demokrasi
adalah Pemilu atau Pilpres. Namun pada kenyataannya, justru dengan Pilpres yang
berlangsung, khususnya di Kota Yogyakarta pada Tahun 2019 justru menimbulkan
ketegangan politik dan sosial yang tidak hanya di level elit secara nasional, akan tetapi
justru muncul ketegangan dan disharmoni sosial di level kampung. Ketegangan dan
disharmoni sosial ini dipicu oleh adanya solidaritas sosial berbasis partai dan
kelompok oleh masing-masing simpatisan partai dan para pendukung calon
presiden, bahkan telah terjadi klaim kampung sebagai kawasan private dan tabu atau
haram dilewati bagi kelompok atau partai tertentu. Fenomena ini menunjukkan
bahwa praktek demokrasi lewat pilpres, khususnya di Kota Yogyakarta justru
menghasilkan ketegangan yang sangat mendalam dan terus berlangsung yang
melibatkan partai tertentu. Disparitas dan jarak sosial semakin renggang. Bahkan
sendi-sendi kehidupan sosial budaya masyarakat yang notabene adalah masyarakat
yang santun, kalem bahkan sebagai kota pendidikan justru tercerabut dari akarnya
dan tergantikan dengan pencitraan sebagai kota yang tidak aman dan rawan konflik,
terutama menjelang pilpres. 2. Kampung Prabowo Selain munculnya kampung Jokowi, juga muncul kampung pasangan capres 02
Prabowo Subianto dan Sandiaga Uno saat pilpres 2019 yang lalu. Kampung Prabowo-
Sandiaga tampak terlihat dari spanduk/baliho yang terpasang di pinggir jalan sekitar
terminal Ngabean Kota Yogyakarta yang merupakan basis pendukung PPP terutama
basis Gerakan Pemuda Ka’bah (GPK). Pada spanduk tersebut bahkan diklaim sebagai
kampung 99% pendukung Prabowo dan Sandiaga. Klaim ini menunjukkan solidaritas
sosial politik warga kampung sekitar terhadap calon yang mereka dukung. Dukungan semacam ini mengandung suatu pesan dan ekspektasi politik atau dan
Fenomena ini, sepanjang penyelenggaraan kampanye para calon. Dari fenomena di
atas, tampak bahwa klaim kampung partai tidak saja tampak dari dominannya
bendera tertentu, akan tetapi juga tampak dari adanya pemasangan spanduk-
spanduk dan baliho tokoh politik atau calon yang mereka usung dalam pilpres. Gambar 6. Contoh Pemasangan Spanduk dan Atribut Partai Politik di suatu Daerah
(Sumber: Dokumentasi Penulis, 2022) Gambar 6. Contoh Pemasangan Spanduk dan Atribut Partai Politik di suatu Daerah
(Sumber: Dokumentasi Penulis, 2022) Intensitas konflik dan ketegangan sosial yang berlangsung selama beberapa periode
penyelenggaraan pesta demokrasi di Yogyakarta, menunjukkan kecenderungan yang Al Oraimi, S. Z. (2020). ‘Diversity and social cohesion in the United Arab Emirates’,
RUDN Journal of Sociology. doi: 10.22363/2313-2272-2020-20-4-837-846. DAFTAR PUSTAKA Al Oraimi, S. Z. (2020). ‘Diversity and social cohesion in the United Arab Emirates’,
RUDN Journal of Sociology. doi: 10.22363/2313-2272-2020-20-4-837-846. Alaverdov, E. (2021) ‘Modern Migration Crisis in Europe and the Role of Diasporas in
Combating the Mutual Hostility between Newcomers and Host Society’, Journal
of
Education
Culture
and
Society,
12(1),
pp. 177–186. doi:
10.15503/jecs2021.1.177.186. Alaverdov, E. (2021) ‘Modern Migration Crisis in Europe and the Role of Diasporas in
Combating the Mutual Hostility between Newcomers and Host Society’, Journal
of
Education
Culture
and
Society,
12(1),
pp. 177–186. doi:
10.15503/jecs2021.1.177.186. SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 SASDAYA
G https://doi.org/10.22146/sasdaya.8621 Ammar Zuhar (2014) ‘Etnisitas dalam Politik (Studi tentang Strategi Calon Legislatif
Etnis Batak dalam Pemilihan Umum Legislatif di Daerah Pemilihan Siak 4
Kabupaten Siak Tahun 2014)’, UIN Maulana Malik Ibrahim. Bannister, J. and O’Sullivan, A. (2013) ‘Civility, community cohesion and antisocial
behaviour: Policy and social harmony’, Journal of Social Policy. doi:
10.1017/S0047279412000736. Berglund, K. and Schwartz, B. (2013) ‘Holding on to the Anomaly of Social
Entrepreneurship Dilemmas in Starting up and Running a Fair-Trade
Enterprise’, Journal of Social Entrepreneurship. doi: 10.1080/19420676.2013.777362. Christian Welzel, (2006). Democratization as an emancipative process: The neglected
role of mass motivations. European Journal of Political Research 45: 871–896, 2006
871 doi: 10.1111/j.1475-6765.2006.00637 Goodman, L. W. (2021) ‘Democratization in Asia: Lessons from the Americas’, in
Democratization,
National
Identity
and
Foreign
Policy
in
Asia. doi:
10.4324/9781003119159-6. Goryacheva, I. Y. (2016) ‘Conclusion and outlook’, Comprehensive Analytical Chemistry. doi: 10.1016/bs.coac.2016.03.011. Gupta, A., Sharma, U. and Gupta, S. K. (2021) ‘The Role of ESG in Sustainable
Development: An Analysis Through the Lens of Machine Learning’, in 2021 IEEE
International
Humanitarian
Technology
Conference,
IHTC
2021. doi:
10.1109/IHTC53077.2021.9698939. Haslinda Syafitri, Warsono Warsono (2020) Primordialisme Dalam Praktek
Demokrasi Di Organisasi Kemahasiswaan (Konflik Sosial Dalam Pemira Bem
Unesa 2020). Kajian Moral dan Kewarganegaraan. Volume 9, Nomor 3. Tahun 2021,
672-688 Heru Nogroho (2012). Demokrasi dan Demokratisasi: Sebuah Kerangka Konseptual
Untuk Memahami Dinamika Sosial-Politik Di Indonesia. Jurnal Pemikiran
Sosiologi Volume 1 No.1, Mei 2012 Howie, L. et al. (2021) ‘Wild and tame zones in times of disharmony: Muslim boys and
belonging in a primary school in Melbourne, Australia’, Journal of Youth Studies. doi 10.1080/13676261.2020.1777265. Iska, S. et al. (2022) ‘Implications of the Pagang Gadai Contract on Disharmony Social
Actors in Minangkabau Community’, Juris: Jurnal Ilmiah Syariah. doi:
10.31958/juris.v21i1.5647. Jan Aart Scholte (2019). After Liberal Global Democracy: New Methodology for New
Praxis,
Fudan
Journal
of
the
Humanities
and
Social
Sciences. https://doi.org/10.1007/s40647-019-00265-3. 75 | Muhammad Arifin Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi … | 76 SASDAYA
G SASDAYA
Gadjah Mada Journal of Humanities, Vol. 7. No. 1, 2023 https://doi.org/10.22146/sasdaya.8621 John S. Dryzek (2006). Transnational Democracy in an Insecure World. International
Political Science Review 2006; 27; 101. Sage Publication John O’Loughlin (2016). Global Democratization. Institute of Behavioral Science and
Department of Geography University of Colorado Campus Box 487 Boulder, CO. 80309-0487 USA., 2016. Keddie, A. (2014) ‘Students’ understandings of religious identities and relations:
Issues of social cohesion and citizenship’, Education, Citizenship and Social Justice. Kristian Stokke (208). Democratization in the Global South: From democratic transitions to
transformative democratic politics. Department of Sociology and Human
Geography, University of Oslo, 2018. Lars-Erik Cederman, Simon Hug, And Andreas Wenger, (2008). Democratization and
War in Political Science. Democratization, Vol.15, No.3, June 2008, pp.509–524
online DOI: 10.1080/13510340801972247 # 2008 Taylor & Francis. Lindah Usman, Atika Marzaman (2019). Demokrasi Berujung Konflik Sosial Pasca
Pemilihan Kepala Desa Jembatan Merah, Kab. Gorontalo Utara. Seminar Nasional
Teknologi, Sains dan Humaniora , (Seman TECH, 2019) Mundt, R. J. (2018) ‘Côte d’Ivoire: Continuity and Change in a Semi-Democracy’, in
Political Reform in Francophone Africa. doi 10.4324/9780429498183-11. Muhammd
Dalhatu
(2019). Cosmopolitian
Democracy:
Re-Evaluation
Of
Globalization & World Economic System. A master’s thesis submitted to the
Graduate Faculty in Liberal Studies in partial fulfillment of the requirements for the
degree of Master of Arts, The City University of New York. Remmer, KL. (1995) New Theoretical Perspectives on Democratization. Comparative Politics, Vol. 28, No. 1 (Oct., 1995), pp. 103-122 Muhammd
Dalhatu
(2019). Cosmopolitian
Democracy:
Re-Evaluation
Of
Globalization & World Economic System. A master’s thesis submitted to the
Graduate Faculty in Liberal Studies in partial fulfillment of the requirements for the
degree of Master of Arts, The City University of New York. Remmer, KL. (1995) New Theoretical Perspectives on Democratization. Comparative Politics, Vol. 28, No. 1 (Oct., 1995), pp. 103-122 Rennuy, N. (2019) ‘The trilemma of eu social benefits law: Seeing the wood and the
trees’, Common Market Law Review. doi: 10.54648/cola2019125. Walsh, F. (2011) ‘Family resilience: A collaborative approach in response to stressful
life challenges’, in Resilience and Mental Health: Challenges Across the Lifespan. doi:
10.1017/CBO9780511994791.012. Walsh, L. et al. (2020) ‘An ecological case-study of the benefits and challenges of
socially-just leadership engaging in “challenging conversations” about social
disharmony’,
Journal
of
Educational
Administration
and
History. doi:
10.1080/00220620.2020.1738361. Westerlund, H. et al. (2022) ‘Visions for intercultural music teacher education in
complex
societies’,
Research
Studies
in
Music
Education. doi:
10.1177/1321103X211032490. SASDAYA
G Disharmoni Sosial Masyarakat Kampung Kota di Era Demokratisasi
|
https://openalex.org/W2604842146
|
https://europepmc.org/articles/pmc5381781?pdf=render
|
English
| null |
Symbol-value association and discrimination in the archerfish
|
PloS one
| 2,017
|
cc-by
| 9,161
|
OPEN ACCESS OPEN ACCESS
Citation: Karoubi N, Leibovich T, Segev R (2017)
Symbol-value association and discrimination in the
archerfish. PLoS ONE 12(4): e0174044. https://doi. org/10.1371/journal.pone.0174044 OPEN ACCESS
Citation: Karoubi N, Leibovich T, Segev R (2017)
Symbol-value association and discrimination in the
archerfish. PLoS ONE 12(4): e0174044. https://doi. org/10.1371/journal.pone.0174044 Citation: Karoubi N, Leibovich T, Segev R (2017)
Symbol-value association and discrimination in the
archerfish. PLoS ONE 12(4): e0174044. https://doi. org/10.1371/journal.pone.0174044 Editor: Christian Agrillo, Universita degli Studi di
Padova, ITALY Editor: Christian Agrillo, Universita degli Studi di
Padova, ITALY Received: November 4, 2016
Accepted: March 2, 2017
Published: April 5, 2017
Copyright: © 2017 Karoubi et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which
permits unrestricted use, distribution, and
reproduction in any medium, provided the original
author and source are credited. Received: November 4, 2016
Accepted: March 2, 2017
Published: April 5, 2017 Symbol-value association and discrimination
in the archerfish Naomi Karoubi1, Tali Leibovich2, Ronen Segev1* 1 Life Sciences Department and Zlotowski Center for Neuroscience, Ben Gurion University of the Negev,
Beer Sheva, Israel, 2 Psychology Department and the Brain and Mind Institute, The University of Western
Ontario, London, Canada * ronensgv@bgu.ac.il * ronensgv@bgu.ac.il a1111111111
a1111111111
a1111111111
a1111111111
a1111111111 RESEARCH ARTICLE Abstract a1111111111
a1111111111
a1111111111
a1111111111
a1111111111 One of the most important aspects of mathematical cognition in humans is the ability to sym-
bolically represent magnitudes and quantities. In the last 20 years it has been shown that
not only humans but also other primates, birds and dolphins can use symbolic representa-
tion of quantities. However, it remains unclear to what extent this ability is spread across the
animal kingdom. Here, by training archerfish to associate variable amounts of rewards with
different geometric shapes, we show for the first time that lower vertebrates can also associ-
ate a value with a symbol and make a decision that maximizes their food intake based on
this information. In addition, the archerfish is able to understand up to four different quanti-
ties and organize them mentally in an ordinal manner, similar to observations in higher verte-
brates. These findings point in the direction of the existence of an approximate magnitude
system in fish. Introduction From counting eggs [1] to picking the pool with the most fish [2], to fighting an intruder lion
only if enough allies are present [3], all of these behaviors reveal an innate notion of quantities
in animals from insects [4] to primates [5]. Furthermore, more complex numerical abilities
such as ordinal judgment or the addition of two quantities have been extensively investigated
in species like birds, bees and non-human primates [6–8] and were found in many cases to
equal at least the abilities of human infants [9]. Copyright: © 2017 Karoubi et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which
permits unrestricted use, distribution, and
reproduction in any medium, provided the original
author and source are credited. Data Availability Statement: All relevant data are
within the paper and its Supporting Information
files. Fishes also demonstrate a natural ability to assess quantities. For example, it has been
demonstrated that in various species such as mosquitofish or angelfish, an individual will
spontaneously join the bigger of two shoals in an attempt to avoid predators, but only when
the difference in the number of individuals is significant and enables an easy discrimination
[10–12]. In addition, other fish can also discriminate small quantities of objects [13,14], recog-
nize the door with the correct number of symbols [15] or encode ordinal information [16]. They are able to perform above chance even when not given access to all the items together
[17] or when they are deprived of the sense of sight [13]. Funding: We gratefully acknowledge financial
support from the Israel Science Foundation (grant
No. 211/15), and the Helmsley Charitable Trust
through the Agricultural, Biological and Cognitive
Robotics Initiative of Ben-Gurion University of the
Negev. All the previous studies used relative numerosity judgments with non-symbolic stimuli
(although see [16]). Eliminating the possible influence of continuous magnitudes in Competing interests: The authors have declared
that no competing interests exist. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 1 / 16 Symbol-value association in the archerfish numerosity comparison tasks is very difficult. Efforts were made to negate this influence by
cleverly manipulating the relationship between number and continuous magnitudes so that
continuous magnitudes will not be a predictive cue of numerosity. However, it has been dem-
onstrated that even under such conditions, continuous magnitudes might influence perfor-
mance [18]]. Animals All the experiments were approved by the Ben-Gurion University of the Negev Animal Care
and Use Committee and were in accordance with the laws of the State of Israel. A total of
twelve adult archerfish, Toxotes chatareus, 6 to 12 cm, 10 to 15 g, were used for this study. They were purchased from a local animal seller. The fish were kept individually in water tanks
(30 cm X 50 cm X 40 cm) filled with brackish water (2–2.5 g of a red sea salts mix per 1 liter of
water) at 25˚–28˚C. The room was illuminated with artificial light on a 16/8 h day/night cycle. The water was filtered and oxygenated by an air pump. Introduction This is true for our study as well, although our work is the first to use abstract
symbols associated with quantities. Homo sapiens has developed advanced mathematical abilities in a way not observed in
other animals, and it started by simply associating a quantity with a symbol. This involves the
capacity to assign a value to an abstract symbol and then manipulate these representations as
though they were the quantities themselves. Being able to tell for example which of two Arabic
numerals is larger is not innate but requires learning. Traditionally it was claimed that this
ability emerged with language and thus could not develop in animals lacking language [19,20]. Recently, however, studies have shown that a few animals can represent numerosities in a
symbolic manner [21–27]. Monkeys were shown to be able to choose between two alternatives
and pick the one that provided the largest food reward [8,28,29]. Chimpanzees can add Arabic
numerals to obtain a reward [5]. Pigeons can associate a number of seeds with a symbol and
peck the one that leads to a larger reward [30], and a parrot was reported to have learned to
associate the vocalization of numerals with the corresponding number of objects [31]. All these results have contributed to a better understanding of the evolution of mathemati-
cal cognition. However, it remains unclear how widespread the ability to associate quantities
and symbolic representations is among vertebrates. In particular, we do not know whether
evolutionary branches that diverged long ago from mammals and birds also possess this abil-
ity. This question is interesting since it may provide clues to the anatomical locations in the
brain that support these cognitive capabilities. However one should keep in mind that it is also
possible that numerical abilities may be the result of convergent evolution and that different
clades developed different mechanisms to solve numerical problems. To address this question, we used the unique capability of the archerfish (Toxotes chatareus)
to shoot a jet of water at targets presented on a computer monitor. We trained the fish to asso-
ciate a quantity of food pellets with symbols and choose the target that was associated with the
highest value of reward. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 Training The fish were trained to spit at targets presented on a LCD monitor (VW2245-T, 21.5", BenQ,
Taiwan) placed 45 cm above the water level on transparent tempered glass (Fig 1). The food
consisted of pellets of similar size of about 3 mm long (Red Parot Granulat, Tropical, Poland)
allowing for clear monitoring of the amount received on each trial. Food pellets were simulta-
neously dropped manually by the experimenter on the side closest to her, and freely derived in
the water until the fish ate them. Depending on the experiment, the fish received between 30 PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 2 / 16 Symbol-value association in the archerfish Fig 1. Experimental setup. A. Schematic representation of the experimental setup and the recording
system. B. Photo of a real experiment (the black background was made darker by image manipulation to
show the shot better). https://doi.org/10.1371/journal.pone.0174044.g001 Fig 1. Experimental setup. A. Schematic representation of the experimental setup and the recording
system. B. Photo of a real experiment (the black background was made darker by image manipulation to
show the shot better). https://doi.org/10.1371/journal.pone.0174044.g001 Fig 1. Experimental setup. A. Schematic representation of the experimental setup and the recording
system. B. Photo of a real experiment (the black background was made darker by image manipulation to
show the shot better). https://doi.org/10.1371/journal.pone.0174044.g001 https://doi.org/10.1371/journal.pone.0174044.g001 https://doi.org/10.1371/journal.pone.0174044.g001 and 100 (+/- 20%) food pellets. They got most of their food intake from the experiments and
only received the equivalent of 10–20 food pellets during the weekend. From experience, we
estimate that the fish reach satiety after eating 100 +/- 20 food pellet per day and would stop
spitting when reaching that level. Sessions were usually a minimum of 48 hours apart to avoid and 100 (+/- 20%) food pellets. They got most of their food intake from the experiments and
only received the equivalent of 10–20 food pellets during the weekend. From experience, we
estimate that the fish reach satiety after eating 100 +/- 20 food pellet per day and would stop
spitting when reaching that level. Sessions were usually a minimum of 48 hours apart to avoid PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 3 / 16 Symbol-value association in the archerfish overfeeding and to maintain the fish in a responsive state. They were not fed between sessions
during the week. Training Initially, the fish were trained to shoot water at images of insects on the screen until they
understood the task and shot at the targets every time. Aims at targets were rewarded with one
food pellet. Then the images were replaced by a single black shape (square, triangle or circle
alternatively). Again, the fish were rewarded with one food pellet for any shot at a target. Sti-
muli were presented using PowerPoint presentations (Microsoft, Seattle, WA, USA). Not all
the fish were able to perform the whole set of experiments but since it was not critical for our
study that the same fish performed all the different experiments, it did not influence our work. Some of them (4) died of natural causes. Some fish were dismissed because they stopped spit-
ting or they lost their ability to shoot straight (6). This phenomenon is well known in the
archerfish research community. Once a fish was dismissed, it was put in the aquarium with the
fish for other projects. All the experiments were recorded with a HD video camera (Handycam, HDR-CX240,
Sony, Japan) at 25 frames per second. The videos were then manually analyzed with Virtual-
Dub to measure reaction times. Reaction time was defined as the time difference between the
onset of the targets and the beginning of the shot of water, similarly to common practice in
fish research [32,33]. Because we signal the start of an experiment with a blinking square, fish
are already paying attention to the screen when the targets appear. Hence there is no “dead
time” when the fish needs to notice the stimuli like in Mamuneas’ experiment [32] for exam-
ple, and thus the reaction time can be a good measure of cognitive performance. Behavioral experiments A session was conducted during a single day and consisted of 36 trials; the fish generally
responded 70% to 100% of the trials. The appearance of the targets was preceded by a black
square (5 cm in height) that blinked three times in the center of the screen, signaling the begin-
ning of a new trial to the fish. The targets were left on the screen for a maximum of two min-
utes or until the fish shot at one target. The stimuli were shapes (square, circle and triangle) of
the same height (2 cm), which were either green, red or black during the experiments, depend-
ing on the fish’s preference (see below). The value associated with each target varied across
experiments. The positions of the target changed randomly between trials and sessions to
avoid bias toward specific locations. They were positioned far enough from each other (mini-
mum 3 cm) to eliminate any doubt as to which target was selected. The experiment was con-
ducted until the fish attained a steady state, defined as at least five days with success rate above
60%. Exception was made for the third experiment with quantities where most of the fish’s
success rate stabilized around 50%. Not all the fish were involved in every experiment with the different quantities but they
always went through an extinction phase (see below) between experiments. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 Natural preference In the first phase, we measured natural preferences for shapes and colors. These sessions con-
sisted of 75 trials, where all three shapes—circle, square and triangle—were presented simulta-
neously during 15 seconds, at random positions to avoid bias for location. All the targets were
the same color during one trial and the colors—green, red and black—were alternated every
trial (Fig 2A), all colors appearing in equal proportions. Each shot at any target was rewarded
with one food pellet, and the color and the shape chosen were recorded. This phase lasted in
general from 5 to 10 days, and provided a dataset of 150 to 250 choices. All but three fish pre-
ferred triangles over squares over circles at a rate that greatly exceeded chance (Fig 2B). In PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 4 / 16 Symbol-value association in the archerfish Fig 2. Fish show a variety of natural preferences. A. Example of sequence of stimuli presented during the
determination of natural preference. B. Natural preference for shapes: percentage of choices for each target
for the whole experiment. C. Stability of natural preference: average natural preference for the first and
second half of the experiment. The dashed line represents the chance level (33%). https://doi.org/10.1371/journal.pone.0174044.g002 Fig 2. Fish show a variety of natural preferences. A. Example of sequence of stimuli presented during the
determination of natural preference. B. Natural preference for shapes: percentage of choices for each target
for the whole experiment. C. Stability of natural preference: average natural preference for the first and
second half of the experiment. The dashed line represents the chance level (33%). https://doi.org/10.1371/journal.pone.0174044.g002 5 / 16 PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 Symbol-value association in the archerfish addition, each fish had a preferred color (green, red or black) which was more or less evenly
distributed among the fish. Fish 10 and 11, whose natural preferences were not as strong as the
other fish, went through a short session (5 days) of preference reinforcement: the favorite tar-
get was rewarded with one food pellet and the least one with none. They reached a choice rate
of 92% and 100% respectively. Persistence of natural preference A comparison of the percentage of choices of the preferred target during the first and the sec-
ond halves of the session showed that the natural preference remained strong over time
although the fish received an equal reward for all targets (Fig 2C). We ran a two tails paired t-
test to determine whether the initial and final choice rate were similar. We obtained a p-value
of 0.7701, which indicates that the initial and final choice rate are indeed similar. These results
confirm that the natural preference for shapes is persistent over time. Learning & value association After the natural preference of each fish was determined, the experiments were conducted
with its favorite color (green, black or red) and only two shapes (except for the last experi-
ment), usually the circle and the triangle, depending on which one the fish preferred the most
and the least. The positions of the targets followed the rules described earlier. In all these
experiments, all the fish started with a clear preference for one target. It usually took a mini-
mum of 6 sessions and up to 30 for them to learn to choose the other target. To make sure that the fish could actually learn to choose their least favorite targets if it was
rewarded, we first conducted a classical conditioning procedure. Here the least favorite target
was rewarded with one food pellet whether the favorite one yielded no reward. During the
experiments with two shapes, each target lead to a reward, the least favorite always being asso-
ciated with the highest reward and the favorite with the lowest. The values of the rewards
depended on the experiment. During the first experiment, we tested the ability for the fish to
discriminate between 1 and 3 associated food pellets. In the second experiment, we tested it
they could choose between 2 and 4, and in the latest, in order to check if they could discrimi-
nate when the difference between rewards was only one food pellet, we tested them with 3
and 4. In the experiment with three shapes, the rewards were inversely proportional to the prefer-
ence for the targets (1 for the triangle, 2 for the square and 3 for the circle). All the different
combinations of targets were presented in equal proportion: the three pairs triangle-square,
triangle-circle and square-circle, as well as the three shapes together. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 The order of the experiments goes from left to right. preference. This enabled us to run several experiments with the same fish by always associating
the least preferred target with the highest amount of reward to avoid a congruence effect. The summary of the participation of every fish to the different experiments is presented in
Table 1. The fish always went through an extinction period between two experiments. The
results of the many extinction procedures that were performed are not shown for the sake of
clarity. The order of the experiments goes from left to right. preference. This enabled us to run several experiments with the same fish by always associating
the least preferred target with the highest amount of reward to avoid a congruence effect. The summary of the participation of every fish to the different experiments is presented in
Table 1. The fish always went through an extinction period between two experiments. The
results of the many extinction procedures that were performed are not shown for the sake of
clarity. The order of the experiments goes from left to right. Statistical analysis All statistical analyses were performed on Matlab. For the three experiments with two shapes,
the chance level was 50%. For the experiment with three shapes, the chance level was set at
45.83%. This is because each session consisted of an equal proportion of each combination (1
versus 2, 1 versus 3, 2 versus 3, and the three shapes representing of 1, 2 and 3 altogether). The
chance level for this experiment was thus the average of three time 50% and once 33%. To determine the statistical significance of each experiment, we calculated the probability
of obtaining the observed results by chance. Since each fish started with a strong preference for
one target, we used its initial success rate—the choice rate during the first day- as the probabil-
ity of success in the binomial distribution. We then simulated 10000 experiments of 36 shots—
a number identical to the number of daily trials—and calculated the probability to observe a
success rate equal or better than the one observed during the last day of the experiment. In this
way, the p values were calculated as ‘number of simulated distributions with number of correct
responses > = observed number of correct responses’. A p-value smaller than 0.005 indicates
that we can reject the hypothesis that the observed initial and final results are identical. Extinction In order to control that the fish were able to unlearn something they just learnt, and since we
needed to be able to conduct several experiments with the same fish for this study and for
future research, we subjected the fish to an extinction procedure between experiments [34]. During these sessions, intercalated between the experiments, the natural preference was rein-
forced again, in the opposite direction from the experiment they had just completed. This was
obligatory since if we had simply switched the rewards associated with the targets, we would
have ended up rewarding the favorite target with the highest amount of food. This congruency
would have made it hard to determine whether the observed effect could be attributed to the
magnitude of the reward or to the natural preference for the shape itself. In this phase, the
fish were presented with the same targets but this time they were rewarded with one food
pellet for their initially favorite target and zero for the other one, thus re-inducing their natural PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 6 / 16 Symbol-value association in the archerfish Table 1. Summary of fish participating in different experiments. Ext. stands for “extinction”. The + sign indicates that the fish took part in the experiment. Natural Preference
Learning and Extinction
1 versus 3
Ext. 2 versus 4
Ext. 3 versus 4
Ext. 1,2,3
Fish 1
+
+
+
+
+
Fish 2
+
Fish 3
+
+
+
+
+
Fish 4
+
+
+
+
+
+
+
Fish 5
+
+
Fish 6
+
+
Fish 7
+
+
Fish 8
+
+
+
+
Fish 9
+
+
Fish 10
+
+
Fish 11
+
+
+
Fish 12
+
https://doi.org/10.1371/journal.pone.0174044.t001 preference. This enabled us to run several experiments with the same fish by always associating
the least preferred target with the highest amount of reward to avoid a congruence effect. The summary of the participation of every fish to the different experiments is presented in
Table 1. The fish always went through an extinction period between two experiments. The
results of the many extinction procedures that were performed are not shown for the sake of
clarity. The order of the experiments goes from left to right. Table 1. Summary of fish participating in different experiments. Ext. stands for “extinction”. The + sign indicates that the fish took part in the experiment. Natural Preference
Learning and Extinction
1 versus 3
Ext. 2 versus 4
Ext. 3 versus 4
Ext. 1,2,3
Fish 1
+
+
+
+
+
Fish 2
+
Fish 3
+
+
+
+
+
Fish 4
+
+
+
+
+
+
+
Fish 5
+
+
Fish 6
+
+
Fish 7
+
+
Fish 8
+
+
+
+
Fish 9
+
+
Fish 10
+
+
Fish 11
+
+
+
Fish 12
+
https://doi.org/10.1371/journal.pone.0174044.t001 Table 1. Summary of fish participating in different experiments. Ext. stands for “extinction”. The + sign indicate preference. This enabled us to run several experiments with the same fish by always associating
the least preferred target with the highest amount of reward to avoid a congruence effect. The summary of the participation of every fish to the different experiments is presented in
Table 1. The fish always went through an extinction period between two experiments. The
results of the many extinction procedures that were performed are not shown for the sake of
clarity. https://doi.org/10.1371/journal.pone.0174044.t001 Learning and extinction After establishing the fish’s natural preference for colors and shapes (see Method), the goal of
this session was to test their ability to learn to spit at a target they did not choose spontaneously
and then check if they were able do unlearn and go back to their initial preference. In the learning phase where only the least favorite target was rewarded, the fish started with
a clear preference (Fig 3A) with at least 65% of the shots in the first session toward their pre-
ferred target. Nevertheless, all the fish learned to shoot at the rewarded target more than 70% PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 7 / 16 Symbol-value association in the archerfish Fig 3. Fish are capable of learning and unlearning. A. Success rate for each fish during the learning
experiment, with normalized axis for days; the inset shows the same results without normalization. B. Averag
rate of correct shots during learning on the first and last days. C. Failure rate for each fish during the extinction
experiment, with normalized time; the inset shows the same results without normalization. D. Average rate of
misses during extinction on the first and last days. The dashed line represents the chance level (50%). https://doi.org/10.1371/journal.pone.0174044.g003 Fig 3. Fish are capable of learning and unlearning. A. Success rate for each fish during the learning
experiment, with normalized axis for days; the inset shows the same results without normalization. B. Average
rate of correct shots during learning on the first and last days. C. Failure rate for each fish during the extinction
experiment, with normalized time; the inset shows the same results without normalization. D. Average rate of
misses during extinction on the first and last days. The dashed line represents the chance level (50%). https://doi.org/10.1371/journal.pone.0174044.g003 https://doi.org/10.1371/journal.pone.0174044.g003 of the time in less than 13 sessions, thus showing a clear ability to learn to choose the rewarded
target (p<0.0001, Fig 3B). Similarly, in the extinction phase, all the fish became proficient in five to seven sessions and
went back to their natural preference (Fig 3C) with a minimum of a 70% choice of the favorite
target (p<0.0001, Fig 3D). Similarly, in the extinction phase, all the fish became proficient in five to seven sessions and
went back to their natural preference (Fig 3C) with a minimum of a 70% choice of the favorite
target (p<0.0001, Fig 3D). Two shape-value association. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 Learning and extinction In these experiments with two targets, we tested whether
the fish could associate different quantities of reward with each shape. In the first experiment, PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 8 / 16 Symbol-value association in the archerfish we tested if the fish would prefer three food pellets rather than one. Fig 4A shows that over the
course of the experiment the fish changed their preference to shoot at the circle (rewarded
Fig 4. Fish can learn to associate value and shape. A. Success rate for each fish on the 1 versus 3
experiment over normalized time; inset: average success rate on the first and last day. B. Success rate for
each fish on the 2 versus 4 experiment over normalized time; inset: average success rate on the first and last
day. C. Success rate for each fish on the 3 versus 4 experiment over normalized time; inset: average success
rate on the first and last day. The dashed line represents the chance level (50%). https://doi.org/10.1371/journal.pone.0174044.g004 Fig 4. Fish can learn to associate value and shape. A. Success rate for each fish on the 1 versus 3
experiment over normalized time; inset: average success rate on the first and last day. B. Success rate for
each fish on the 2 versus 4 experiment over normalized time; inset: average success rate on the first and last
day. C. Success rate for each fish on the 3 versus 4 experiment over normalized time; inset: average success
rate on the first and last day. The dashed line represents the chance level (50%). https://doi org/10 1371/journal pone 0174044 g004 Fig 4. Fish can learn to associate value and shape. A. Success rate for each fish on the 1 versus 3
experiment over normalized time; inset: average success rate on the first and last day. B. Success rate for
each fish on the 2 versus 4 experiment over normalized time; inset: average success rate on the first and last
day. C. Success rate for each fish on the 3 versus 4 experiment over normalized time; inset: average success
rate on the first and last day. The dashed line represents the chance level (50%). https://doi.org/10.1371/journal.pone.0174044.g004 https://doi.org/10.1371/journal.pone.0174044.g004 we tested if the fish would prefer three food pellets rather than one. Learning and extinction Fig 4A shows that over the
course of the experiment the fish changed their preference to shoot at the circle (rewarded
with three) significantly more often than the triangle. The average choice rate on the last day
was around 80%, which is significantly different from the initial 5% (p<0.0001, Fig 4A inset). we tested if the fish would prefer three food pellets rather than one. Fig 4A shows that over the
course of the experiment the fish changed their preference to shoot at the circle (rewarded
with three) significantly more often than the triangle. The average choice rate on the last day
was around 80%, which is significantly different from the initial 5% (p<0.0001, Fig 4A inset). PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 9 / 16 Symbol-value association in the archerfish Fig 5. Fish can associate three values and with three shapes. A. Success rate for each fish on the 1, 2, 3
experiment over normalized time. Inset: average success rate on the first and last day. The dashed line
represents the chance level (45.83%). B. Success rate for the three combinations with two targets. The
dashed line represents the chance level (50%). C. Success rate for the combination with three targets
presented simultaneously. The dashed line represents the chance level (33%). https://doi.org/10.1371/journal.pone.0174044.g005 Fig 5. Fish can associate three values and with three shapes. A. Success rate for each fish on the 1, 2, 3
experiment over normalized time. Inset: average success rate on the first and last day. The dashed line
represents the chance level (45.83%). B. Success rate for the three combinations with two targets. The
dashed line represents the chance level (50%). C. Success rate for the combination with three targets
presented simultaneously. The dashed line represents the chance level (33%). https://doi.org/10.1371/journal.pone.0174044.g005 https://doi.org/10.1371/journal.pone.0174044.g005 Thus fish appeared to be able to distinguish between one and three food pellets, and change
their shape preference accordingly. After an extinction phase (see Methods), the fish had to choose between targets associated
with two (triangle) and four food pellets (circle). Again, the results clearly showed that the fish
were able to shift their preference (Fig 4B), since they preferred the circle at the end of the
experiment (76% as compared to 12% initially, p<0.0001) with results significantly above
chance (Fig 4B inset). PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 Learning and extinction Some fish are able to organize shapes according to the value associated with them. A. Details of
the experiment with three shapes for the pairs comparisons for Fish 4. B. Details of the experiment with three
shapes for the pairs comparisons for fish 11. C. Details of the experiment with three shapes for the pairs
comparisons for fish 12. Fig 6. Some fish are able to organize shapes according to the value associated with them. A. Details of
the experiment with three shapes for the pairs comparisons for Fish 4. B. Details of the experiment with three
shapes for the pairs comparisons for fish 11. C. Details of the experiment with three shapes for the pairs
comparisons for fish 12. https://doi.org/10.1371/journal.pone.0174044.g006 https://doi.org/10.1371/journal.pone.0174044.g006 Since the fish encountered each pair of shapes only nine times per session and may not
have spitted every time, the results’ variance is high. Thus, to increase the significance of the
observations, we chose to analyze in Fig 6 the moving average (3 days) of the success rate. This more detailed depiction of results for the pair conditions reveals that only Fish 4 (Fig
6A) shows an upward trend for each combinations, whereas the two other fish seem to oscil-
late (Fig 6B and 6C). It is also important to notice that since we conducted the experiment
until we saw a steady state in the overall score rather than in each subcategory separately,
we cannot state that the fish were unable to pick the correct answer in the three two-shape
combinations. On the contrary, the fact that Fish 4 succeeded suggests that given enough
time, the others might also be able to reach a stable success rate above chance level in every
condition. Learning and extinction Next, we tested if the fish could still discriminate when the difference between targets was
reduced to only one food pellet. Thus, with the same setup we examined whether the fish
could distinguish between three and four (Fig 4C), after an extinction phase. Here, we
observed a variety of learning capabilities in the fish population. One fish clearly learned to
choose the most highly rewarded target (Fish 4, Fig 4C), whereas another fish did not change
its preference, with an initial and final rate of about 40% (Fish 8, Fig 4C). Another three fish
changed their preference from the original to about an equal proportion for both targets. Although the final success rate (53%) in this experiment was lower than in the previous ones
with a difference of two food pellets, it was still significantly higher than the initial rate (15%,
p<0.0001). Three shape-value association. To test the ability of the fish to associate values with sym-
bols in a more complex setup, we tested the fish with three shapes associated with three
amounts of reward. Spitting at the triangle was associated with one food pellet, two when the
square was chosen and three for the circle. The results showed that although the initial success
rate was close to chance, the fish eventually learned to choose the most rewarded targets with
an average rate of about 70% (p<0.0001, Fig 5A). g
p
g
When breaking down the results between the three pair comparisons (1 versus 2, 1 versus 3
and 2 versus 3, Fig 5B) and the one with three shapes (Fig 5C), it appears clearly that Fish 4
was able to choose the most rewarded target in all conditions. Fish 11 and 12 succeeded signifi-
cantly above chance with three targets but their overall results for the two shapes combination
do not allow us to clearly state that they succeeded. 10 / 16 PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 Symbol-value association in the archerfish Fig 6. Some fish are able to organize shapes according to the value associated with them. A. Details of
the experiment with three shapes for the pairs comparisons for Fish 4. B. Details of the experiment with three
shapes for the pairs comparisons for fish 11. C. Details of the experiment with three shapes for the pairs
comparisons for fish 12. https://doi.org/10.1371/journal.pone.0174044.g006 Fig 6. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 Success rates depend on ratio of rewards Current theories about the existence of an organized representation of magnitudes in humans
and animals [35,36] are based on the existence of a correlation between the success rate when
comparing two values and the ratio between those two. Studies have shown in humans and
other primates that accuracy decreases and latency increases as the ratio between two values
gets larger [35,37] and it is true even during comparison [36,38] of symbolic representations. Fig 7A shows the average success rate over the last three days of each experiment of two-
shape comparison. We also show the results of the fourth experiment (with three shapes) for
the three conditions with two shapes. Scores for the two experiments of 1 versus 3 (first and
fourth experiment) are identical and their representations on the graph are not distinguish-
able. The other scores also follow closely the linear regression. The only outlier is the result
for 1 versus 2 in the three-shape experiment that falls below the general trend. However, the
mean score for the two experiments with the 0.5 ratio (green dot) falls exactly on the predictive
curve. Current theories about the existence of an organized representation of magnitudes in humans
and animals [35,36] are based on the existence of a correlation between the success rate when
comparing two values and the ratio between those two. Studies have shown in humans and
other primates that accuracy decreases and latency increases as the ratio between two values
gets larger [35,37] and it is true even during comparison [36,38] of symbolic representations. Fig 7A shows the average success rate over the last three days of each experiment of two-
shape comparison. We also show the results of the fourth experiment (with three shapes) for
the three conditions with two shapes. Scores for the two experiments of 1 versus 3 (first and
fourth experiment) are identical and their representations on the graph are not distinguish-
able. The other scores also follow closely the linear regression. The only outlier is the result
for 1 versus 2 in the three-shape experiment that falls below the general trend. However, the
mean score for the two experiments with the 0.5 ratio (green dot) falls exactly on the predictive
curve. Interestingly, the final success rates per pair for Fish 4 (Fig 6A) also follow exactly this pre-
diction and Fish 12 (Fig 6C) seems to be on the same track. Discussion & conclusion https://doi.org/10.1371/journal.pone.0174044.g007 https://doi.org/10.1371/journal.pone.0174044.g007 an organized representation of the values associated with each shape in order to be able to
mentally compare them to each other in every set of choice. Although the progress from the
initial to final success rates was considerably lower than in the previous experiments, it
remained significantly higher than chance indicating that fish can compare more than two val-
ues and organize them mentally. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 Discussion & conclusion Previous studies revealed that animals such as primates or birds are able to understand and
manipulate symbolic representation of quantities [21–27]. Here we show for the first time that
fish are also able of such an abstraction. Building on the natural preference for shapes in archerfish provided a powerful tool to
investigate decision making, and made shifts in preference more salient. Almost all the fish
became proficient in the tasks and successfully shifted away from their initial preference
toward the target associated with the largest food reward. This suggests that fish are able to
associate different abstract symbols with different quantities of reward. The different experi-
ments with two targets revealed that the fish are not only able to discriminate between ‘one’
and ‘many’ but also between two quantities bigger than one, and do so even when the differ-
ence between the two is smaller. While the final choice rates in the third experiment (3 versus 4) were roughly equal, this
result nevertheless indicates that fish perceived a difference between the two values. Indeed,
had they estimated the rewards as equal, they would have kept choosing the triangle just like
they did during the natural preference phase, when all targets led to the same reward (Fig 2). Thus this experiment indicates that the fish can discriminate between quantities that are sepa-
rated by only one unit, at least when the rewards are smaller or equal to four. To determine whether the fish were able to associate more than two values with symbols,
we conducted the three shapes experiment. The difficulty of the decision in this experiment
was due to the fact that the combination of symbols changed every trial. Thus, the fish needed PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 11 / 16 Symbol-value association in the archerfish Fig 7. Ratio effect and fish reaction. A. Effect of value ratio over success rate; the values represent the
average over the last three days of the experiment. The error bars represent the standard error. The linear
regression is depicted in red. B. Effect of value ratio over reaction time. https://doi.org/10.1371/journal.pone.0174044.g007 Fig 7. Ratio effect and fish reaction. A. Effect of value ratio over success rate; the values represent the
average over the last three days of the experiment. The error bars represent the standard error. The linear
regression is depicted in red. B. Effect of value ratio over reaction time. Continuous magnitudes as representation of quantities It was thought for a long time that humans and some animals possess a discrete representation
of quantities [9,36]. However, recent studies suggest that it is virtually impossible to remove
all influence of continuous magnitudes [43], and thus it seems more likely that animals and
humans developed instead a continuous representation of magnitudes. We try here to identify
the potential magnitudes used by the fish to determine the value of rewards associated with a
target. Yet, although it appears clearly that the archerfish successfully did so, our experiments
did not permit to determine which parameters the fish used to encode those values. Our behavioral experiments were not based on a simple visual comparison task as was con-
ducted with other fish [10–13,15]. Indeed, the two values to be compared, the number of food
pellets, are never present simultaneously. Therefore, the fish need to encode and store the
value they attribute to each symbol in order to mentally compare it with the values they will
encounter later. Our experiments show some similarities with the one conducted by Dadda
[17] where mosquitofish saw members of a group sequentially and not all at once. However,
since this setup did not use symbols, the mosquitofish could easily base their decision on some
continuous magnitude directly linked to the stimulus such as the time it takes to see all the
individuals. It seems very unlikely that the archerfish based their choice on only one continuous magni-
tude linked to the amount of food pellets. Indeed, the food repartition was influenced by too
many factors. Since the experimenter always dropped the food on the same side of the aquar-
ium, the fish rapidly learned to position themselves where the pellets would fall, just as they do
when they hunt [44]. Thus, they often caught some food when it reached the water or even
right before, while the other pieces started floating and spreading randomly immediately
because of the flow generated by the air pump. In addition, the fish are close to the surface
when they expect food, giving them a maximum viewing angle of 90˚ [45] that does not
encompass the whole aquarium’s surface at once, potentially preventing them from seeing
all the food. Success rates depend on ratio of rewards The analysis of the success rates
in pair choices thus suggests the existence of a ratio effect in the archerfish as predicted by
Weber’s law [39], hinting the existence of an organized system to represent magnitudes. To confirm this intuition we also analyzed reaction times. If the fish made a binary decision
(‘less’ vs. ‘more’), the reaction time should not change as the distance between the associated
rewards varies. By contrast, if fish are able to map the values associated with each target on a
mental magnitude line [9], reaction time should rise as the comparison becomes harder, as
observed in humans and other animals [40,41]. Fig 7B shows the average reaction times across all fish during the last day of the experi-
ment as a function of the ratio of rewards. We did not include the last experiment with the
three shapes in this analysis since the number of choices increased the complexity of the PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 12 / 16 Symbol-value association in the archerfish experiment exponentially and thus impacted the reaction time of the fish. This analysis
reveals that as the ratio of reward approaches one, the reaction time increases, indicating
that the task became harder for the fish and confirming the existence of an organized
mental representation of values. The results are also coherent with symbol discrimination in
humans [42], where the time to determine which one of two Arabic numbers is the biggest
also depends on their ratio. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 Supporting information S1 Data. Experimental raw data. One line correspond to a session for tabs 1–6 and first part
of tab 7. Second part of tab 7 contains the details of each session. Tab 8 contains the number of
shot during the last session as well as the reaction times. (XLSX) Continuous magnitudes as representation of quantities Therefore, it is likely that if the fish used visual continuous magnitudes, they
needed to use all available variables (density, covered area, etc.) and not only one to evaluate
the amount of food present. It is also possible that the fish uses additional magnitudes to determine which symbol yields
more food. For example, satiety could be a parameter, or the effort required to eat all the food
pellets (time, physical effort. . .). However, the random dispersion of the food pellets renders
those magnitude very noisy, which is coherent both with the observed ratio effect observed
and the literature [36]. Although many factors can influence the continuous magnitudes, since we do not have a
way to equate all of them (time to grab, dispersion, satiety . . .) and they are correlated with the
number of food pellets, it is likely that the fish used those magnitudes as cues to determine
how much food they got. We can thus only conclude that the fish possess a magnitude sense
[46,47] of the amount of reward. The influence of continuous magnitudes is not crucial for the
conclusions of the current work since it is possible that the symbols are connected with both
number and continuous magnitudes, as demonstrated in humans [48]]. 13 / 16 PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 Symbol-value association in the archerfish Effect of learning on success rate It is worthwhile noticing that not all the fish showed a similar level of success in the different
tasks. Several factors could explain this effect: it is probable that just like in humans [49], there
is a range of cognitive abilities and not all the fish present the same aptitudes. A recent review
of cognitive experiments performed with fish also suggests the existence of such a phenome-
non [50]. Additionally, they did not all perform the whole set of experiments. Only Fish 4 went
through each step and it is interesting to see that it is also the fish with the best results in the
two last experiments. This could indicate that the ability to associate a value with a shape can
be trained and improved and that with enough practice, archerfish could succeed in tasks
more complex than the ones tested here. To conclude, our experiments revealed that archerfish are able to associate values of
rewards with abstract symbol, compare them and consistently choose the more rewarding tar-
get. We also saw that their success rate and reaction time are correlated with the ratio between
the rewards. These results suggest that archerfish possess an organized mental representation
of magnitudes that enables them to perform comparisons, rather than a simple binary notion
of ‘more’ and ‘less’. Acknowledgments We thank Gustavo Glusman and Asya Mikhaylov for technical assistance and Zvika Abramsky
for his valuable suggestions. We gratefully acknowledge financial support from the Israel Sci-
ence Foundation (grant No. 211/15), and the Helmsley Charitable Trust through the Agricul-
tural, Biological and Cognitive Robotics Initiative of Ben-Gurion University of the Negev. Conceptualization: NK RS. Conceptualization: NK RS. Data curation: NK. Data curation: NK. Formal analysis: NK. Investigation: NK. Methodology: NK. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 References 1. Lyon BE. Egg recognition and counting reduce costs of avian conspecific brood parasitism. Nature
2003 Apr 3; 422(6931):495–499. https://doi.org/10.1038/nature01505 PMID: 12673243 2. Katz MW, Abramsky Z, Kotler BP, Rosenzweig ML, Alteshtein O, Vasserman G. Optimal foraging of lit-
tle egrets and their prey in a foraging game in a patchy environment. Am Nat 2013 Mar; 181(3):381–
395. https://doi.org/10.1086/669156 PMID: 23448887 3. Wilson ML, Britton NF, Franks NR. Chimpanzees and the mathematics of battle. Proc Biol Sci 2002 Jun
7; 269(1496):1107–1112. https://doi.org/10.1098/rspb.2001.1926 PMID: 12061952 4. Dacke M, Srinivasan MV. Evidence for counting in insects. Anim Cogn 2008 Oct; 11(4):683–689. https://doi.org/10.1007/s10071-008-0159-y PMID: 18504627 5. Boysen ST, Berntson GG. Numerical competence in a chimpanzee (Pan troglodytes). J Comp Psychol
1989 Mar; 103(1):23–31. PMID: 2924529 6. Ferster CB. Arithmetic Behavior in Chimpanzees. Sci Am 1964 May; 210:98–106. PMID: 14154103 7. Matsuzawa T. Use of numbers by a chimpanzee. Nature 1985 May 2–8; 315(6014):57–59. PMID:
3990808 8. Washburn DA, Rumbaugh DM. Ordinal judgments of numerical symbols by macaques (Macaca
mulatta). Psychol Sci 1991 May; 2(3):190–193. https://doi.org/10.1111/j.1467-9280.1991.tb00130.x
PMID: 11537106 9. Gallistel CR, Gelman R. Preverbal and verbal counting and computation. Cognition 1992 Aug; 44(1–
2):43–74. PMID: 1511586 10. Agrillo C, Dadda M, Bisazza A. Quantity discrimination in female mosquitofish. Anim Cogn 2007 Jan; 10
(1):63–70. https://doi.org/10.1007/s10071-006-0036-5 PMID: 16868736 11. Agrillo C, Dadda M, Serena G, Bisazza A. Do fish count? Spontaneous discrimination of quantity in
female mosquitofish. Anim Cogn 2008 Jul; 11(3):495–503. https://doi.org/10.1007/s10071-008-0140-9
PMID: 18247068 12. Gomez-Laplaza LM, Gerlai R. Can angelfish (Pterophyllum scalare) count? Discrimination between dif-
ferent shoal sizes follows Weber’s law. Anim Cogn 2011 Jan; 14(1):1–9. https://doi.org/10.1007/
s10071-010-0337-6 PMID: 20607574 13. Bisazza A, Tagliapietra C, Bertolucci C, Foa A, Agrillo C. Non-visual numerical discrimination in a blind
cavefish (Phreatichthys andruzzii). J Exp Biol 2014 Jun 1; 217(Pt 11):1902–1909. https://doi.org/10. 1242/jeb.101683 PMID: 24871921 14. DeLong CM, Barbato S, O’Leary T, Wilcox KT. Small and large number discrimination in goldfish (Car-
assius auratus) with extensive training. Behav Processes 2016 Nov 24. 15. Agrillo C, Dadda M, Serena G, Bisazza A. Use of number by fish. PLoS One 2009; 4(3):e4786. https://
doi.org/10.1371/journal.pone.0004786 PMID: 19274079 16. Petrazzini ME, Lucon-Xiccato T, Agrillo C, Bisazza A. Use of ordinal information by fish. Sci Rep 2015
Oct 26; 5:15497. https://doi.org/10.1038/srep15497 PMID: 26499450 17. Dadda M, Piffer L, Agrillo C, Bisazza A. Spontaneous number representation in mosquitofish. Cognition
2009 Aug; 112(2):343–348. https://doi.org/10.1016/j.cognition.2009.05.009 PMID: 19520367 18. Leibovich T, Henik A. Project administration: NK. Resources: RS. Supervision: RS. Validation: RS TL. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 14 / 16 Symbol-value association in the archerfish PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 References Mamuneas D, Spence AJ, Manica A, King AJ. Bolder stickleback fish make faster decisions, but they
are not less accurate. Behav Ecol 2015; 26(1):91–96. 33. Lucon-Xiccato T, Bisazza A. Male and female guppies differ in speed but not in accuracy in visual dis-
crimination learning. Anim Cogn 2016 Jul; 19(4):733–744. https://doi.org/10.1007/s10071-016-0969-2
PMID: 26920920 34. Bouton ME, Moody EW. Memory processes in classical conditioning. Neurosci Biobehav Rev 2004
Nov; 28(7):663–674. https://doi.org/10.1016/j.neubiorev.2004.09.001 PMID: 15555676 35. Jordan KE, Brannon EM. Weber’s Law influences numerical representations in rhesus macaques (Macaca
mulatta). Anim Cogn 2006 Jul; 9(3):159–172. https://doi.org/10.1007/s10071-006-0017-8 PMID: 16575587 36. Dehaene S. The number sense: How mathematical knowledge is embedded in our brains. 1997. 37. Cantlon JF, Brannon EM. Shared system for ordering small and large numbers in monkeys and humans. Psychol Sci 2006 May; 17(5):401–406. https://doi.org/10.1111/j.1467-9280.2006.01719.x PMID: 16683927 38. Piazza M. Neurocognitive start-up tools for symbolic number representations. Trends Cogn Sci 2010
Dec; 14(12):542–551. https://doi.org/10.1016/j.tics.2010.09.008 PMID: 21055996 39. Fechner G. Elements of psychophysics.: Holt, Rinehart & Winston New York; 1965. 40. Feigenson L, Dehaene S, Spelke E. Core systems of number. Trends Cogn Sci 2004 Jul; 8(7):307–
314. https://doi.org/10.1016/j.tics.2004.05.002 PMID: 15242690 41. Cantlon JF, Platt ML, Brannon EM. Beyond the number domain. Trends Cogn Sci 2009 Feb; 13(2):83–
91. https://doi.org/10.1016/j.tics.2008.11.007 PMID: 19131268 42. Moyer RS, Landauer TK. Time required for judgements of numerical inequality. Nature 1967 Sep 30;
215(5109):1519–1520. PMID: 6052760 43. Leibovich T, Katzin N, Harel M, Henik A. From ‘sense of number’to ‘sense of magnitude’–The role of
continuous magnitudes in numerical cognition. Behav Brain Sci 2016:1–62. 44. Wohl S, Schuster S. The predictive start of hunting archer fish: a flexible and precise motor pattern per-
formed with the kinematics of an escape C-start. J Exp Biol 2007 Jan; 210(Pt 2):311–324. https://doi. org/10.1242/jeb.02646 PMID: 17210967 45. Schuster S, Rossel S, Schmidtmann A, Jager I, Poralla J. Archer fish learn to compensate for complex
optical distortions to determine the absolute size of their aerial prey. Curr Biol 2004 Sep 7; 14(17):1565–
1568. https://doi.org/10.1016/j.cub.2004.08.050 PMID: 15341743 46. Leibovich T, Henik A. Magnitude processing in non-symbolic stimuli. Front Psychol 2013 Jun 25; 4:375. https://doi.org/10.3389/fpsyg.2013.00375 PMID: 23805121 47. Gebuis T, Cohen Kadosh R, Gevers W. Sensory-integration system rather than approximate number
system underlies numerosity processing: A critical review. Acta Psychol (Amst) 2016 Nov; 171:17–35. 48. Merkley R, Scerif G. Continuous visual properties of number influence the formation of novel symbolic
representations. References Comparing performance in discrete and continuous comparison tasks. Q J Exp
Psychol (Hove) 2014 May; 67(5):899–917. 19. Brysbaert M, Fias W, Noel MP. The Whorfian hypothesis and numerical cognition: is ’twenty-four’ pro-
cessed in the same way as ’four-and-twenty’? Cognition 1998 Apr; 66(1):51–77. PMID: 9675978 20. Spaepen E, Coppola M, Spelke ES, Carey SE, Goldin-Meadow S. Number without a language model. Proc Natl Acad Sci U S A 2011 Feb 22; 108(8):3163–3168. https://doi.org/10.1073/pnas.1015975108
PMID: 21300893 21. Olthof A, Iden CM, Roberts WA. Judgements of ordinality and summation of number symbols by squir-
rel monkeys (Saimiri sciureus). J Exp Psychol Anim Behav Process 1997 Jul; 23(3):325–339. PMID:
9206027 22. Beran MJ. Summation and numerousness judgments of sequentially presented sets of items by chim-
panzees (Pan troglodytes). J Comp Psychol 2001 Jun; 115(2):181–191. PMID: 11459165 23. Beran MJ, Beran MM, Harris EH, Washburn DA. Ordinal judgments and summation of nonvisible sets
of food items by two chimpanzees and a rhesus macaque. J Exp Psychol Anim Behav Process 2005
Jul; 31(3):351–362. https://doi.org/10.1037/0097-7403.31.3.351 PMID: 16045389 24. Beran MJ, Evans TA, Harris EH. Perception of Food Amounts by Chimpanzees Based on the Number,
Size, Contour Length and Visibility of Items. Anim Behav 2008 May; 75(5):1793–1802. https://doi.org/
10.1016/j.anbehav.2007.10.035 PMID: 19412322 PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 15 / 16 Symbol-value association in the archerfish 25. Kilian A, Yaman S, von Fersen L, Gunturkun O. A bottlenose dolphin discriminates visual stimuli differ-
ing in numerosity. Learn Behav 2003 May; 31(2):133–142. PMID: 12882372 26. Pepperberg IM. Grey parrot numerical competence: a review. Anim Cogn 2006 Oct; 9(4):377–391. https://doi.org/10.1007/s10071-006-0034-7 PMID: 16909236 27. Pepperberg IM, Carey S. Grey parrot number acquisition: the inference of cardinal value from ordinal
position on the numeral list. Cognition 2012 Nov; 125(2):219–232. https://doi.org/10.1016/j.cognition. 2012.07.003 PMID: 22878117 28. Boysen ST, Himes GT. Current issues and emerging theories in animal cognition. Annu Rev Psychol
1999; 50:683–705. https://doi.org/10.1146/annurev.psych.50.1.683 PMID: 15012466 29. Biro D, Matsuzawa T. Use of numerical symbols by the chimpanzee (Pan troglodytes): Cardinals, ordi-
nals, and the introduction of zero. Anim Cogn 2001 Nov; 4(3–4):193–199. https://doi.org/10.1007/
s100710100086 PMID: 24777509 30. Olthof A, Roberts WA. Summation of symbols by pigeons (Columba livia): the importance of number
and mass of reward items. J Comp Psychol 2000 Jun; 114(2):158–166. PMID: 10890587 31. Pepperberg IM. Further evidence for addition and numerical competence by a Grey parrot (Psittacus
erithacus). Anim Cogn 2012 Jul; 15(4):711–717. PMID: 22402776 32. PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017 References Q J Exp Psychol (Hove) 2015; 68(9):1860–1870. 49. Halberda J, Mazzocco MM, Feigenson L. Individual differences in non-verbal number acuity correlate
with maths achievement. Nature 2008 Oct 2; 455(7213):665–668. https://doi.org/10.1038/nature07246
PMID: 18776888 50. Lucon-Xiccato T, Bisazza A. Individual differences in cognition among teleost fishes. Behav Processes
2017. 16 / 16 PLOS ONE | https://doi.org/10.1371/journal.pone.0174044
April 5, 2017
|
https://openalex.org/W2774383662
|
https://infoscience.epfl.ch/record/274831/files/scoap3-fulltext.pdf
|
English
| null |
Search for the flavor-changing neutral current interactions of the top quark and the Higgs boson which decays into a pair of b quarks at $$ \sqrt{s}=13 $$ TeV
|
The Journal of high energy physics/The journal of high energy physics
| 2,018
|
cc-by
| 18,457
|
Open Access, Copyright CERN, Published for SISSA by
Springer Received: December 6, 2017
Revised: March 13, 2018
Accepted: June 11, 2018
Published: June 20, 2018 Received: December 6, 2017
Revised: March 13, 2018
Accepted: June 11, 2018
Published: June 20, 2018 Received: December 6, 2017
Revised: March 13, 2018
Accepted: June 11, 2018
Published: June 20, 2018 Search for the flavor-changing neutral current
interactions of the top quark and the Higgs boson
which decays into a pair of b quarks at √s = 13 TeV JHEP06(2018)102 The CMS collaboration for the benefit of the CMS Collaboration. The CMS collaboration E-mail: cms-publication-committee-chair@cern.ch Abstract: A search for flavor-changing neutral currents (FCNC) in events with the top
quark and the Higgs boson is presented. The Higgs boson decay to a pair of b quarks is
considered. The data sample corresponds to an integrated luminosity of 35.9 fb−1 recorded
by the CMS experiment at the LHC in proton-proton collisions at √s = 13 TeV. Two
channels are considered: single top quark FCNC production in association with the Higgs
boson (pp →tH), and top quark pair production with FCNC decay of the top quark (t →
qH). Final states with one isolated lepton and at least three reconstructed jets, among which
at least two are associated with b quarks, are studied. No significant deviation is observed
from the predicted background. Observed (expected) upper limits at 95% confidence level
are set on the branching fractions of top quark decays, B(t →uH) < 0.47% (0.34%) and
B(t →cH) < 0.47% (0.44%), assuming a single nonzero FCNC coupling. Keywords: FCNC Interaction, Hadron-Hadron scattering (experiments), Higgs physics,
Top physics ArXiv ePrint: 1712.02399 ArXiv ePrint: 1712.02399 https://doi.org/10.1007/JHEP06(2018)102 for the benefit of the CMS Collaboration. Contents
1
Introduction
1
2
The CMS detector
2
3
Monte Carlo simulation
3
4
Event selection
4
5
Event reconstruction and multivariate analysis
5
6
Estimation of systematic uncertainties
6
7
Results
10
8
Summary
13
The CMS collaboration
18 Contents
1
Introduction
1
2
The CMS detector
2
3
Monte Carlo simulation
3
4
Event selection
4
5
Event reconstruction and multivariate analysis
5
6
Estimation of systematic uncertainties
6
7
Results
10
8
Summary
13
The CMS collaboration
18 1
2
3
4
5
6
10
13
18 JHEP06(2018)102 1
Introduction A recently discovered fundamental particle has properties that are consistent with the
standard model (SM) predictions for the Higgs boson, H [1–4]. In the SM, flavor-changing
neutral currents (FCNC) are forbidden at tree level and are strongly suppressed in loop
corrections by the Glashow-Iliopoulos-Maiani (GIM) mechanism [5] with the SM branching
fraction of t →qH predicted to be O(10−15) [6–8]. Several extensions of the SM incorporate
significantly enhanced FCNC behavior that can be directly probed at the CERN LHC [8, 9]. The FCNC processes that correspond to tH interactions are described by the following
effective Lagrangian: L =
X
q=u,c
g
√
2t κHqt
fL
HqPL + fR
HqPR
q H + h.c.,
(1.1) (1.1) where g is the weak coupling constant, PL and PR are chirality projectors in spin space, κHqt
is the effective coupling, fL
Hq and fR
Hq are left- and right-handed complex chiral parameters
with a unitarity constraint of |fL
Hq|2 + |fR
Hq|2 = 1. The tH FCNC interaction is studied
in this analysis in two channels: the associated production of a single top quark with the
Higgs boson (ST), as well as in FCNC decays of top quarks in tt semileptonic events (TT). In this analysis, H →bb decays are considered. This is the first time that the analysis of
the ST mode is presented. Representative Feynman diagrams of the studied processes are
shown in figure 1. – 1 – u/c
g
u/c
t
H
W+
b
νℓ
ℓ+
¯b
b
g
g
g
t
H
W+
b
νℓ
ℓ+
¯u/¯c
b
¯b
¯t
Figure 1. Representative Feynman diagrams for FCNC tH processes: associated production of the
top quark with the Higgs boson (left), and FCNC decay of the top antiquark in tt events (right). The FCNC vertex is indicated by the bullet. g
g
g
t
H
W+
b
νℓ
ℓ+
¯u/¯c
b
¯b
¯t Figure 1. Representative Feynman diagrams for FCNC tH processes: associated production of the
top quark with the Higgs boson (left), and FCNC decay of the top antiquark in tt events (right). The FCNC vertex is indicated by the bullet. JHEP06(2018)102 Earlier analyses by the ATLAS [10, 11] and CMS [12] Collaborations have probed
κHqt in top quark decays in tt events. 1
Introduction The ATLAS search at center-of-mass energy of
13 TeV investigated the t →qH decay with the Higgs boson decaying to two photons to set
observed (expected) upper limits at 95% confidence level (CL) on the branching fractions
B(t →uH) and B(t →cH) of 0.24% (0.17%) and 0.22% (0.16%), respectively [11]. The
CMS analysis at √s = 8 TeV utilized the Higgs boson decays into either boson or fermion
pairs to set observed (expected) upper limits of 0.55% (0.40%) and 0.40% (0.43%) on
B(t →uH) and B(t →cH), respectively [12]. For the signal processes, we consider the cross section times branching fraction with
a specific signature for single top quark t(→ℓ+νb)H(→bb) and pair production t(→
ℓ+νb)t(→u/cH(→bb)), with ℓ= e, µ, or τ. The analysis also considers the charge-
conjugate process. The predicted cross section at 13 TeV for single top quark and antiquark
FCNC production in association with the Higgs boson under the assumption of coupling
strengths κHut = 1, κHct = 0 (κHct = 1, κHut = 0) is 13.8 (1.90) pb, where the cross section
calculation is based on the leading order (LO) set of NNPDF 2.3 parton distribution
functions (PDFs) [13]. In the case of the production of tt semileptonic events with top
quark FCNC decay, the predicted cross section is 37.0 pb and is independent of the type
of the coupling. By exploiting a simultaneous analysis of both the TT and ST processes,
an improved sensitivity to κHut can be achieved, as the ST production via the up quark is
enhanced by the proton PDFs. This analysis uses data that correspond to an integrated luminosity of 35.9 fb−1 [14]
recorded in 2016 by the CMS experiment at the LHC in proton-proton (pp) collisions at
√s = 13 TeV. Events with exactly one isolated lepton (electron or muon) and with at least
three jets, among which at least two are associated with b quarks, are considered. 3
Monte Carlo simulation The generation of simulated signal events is done at LO with MadGraph5 amc@nlo
2.3.3 [16, 17]. Up to two additional partons are simulated by the Monte Carlo (MC)
generator in the initial hard process for the top quark pair production mode. The MLM [18]
matching scheme is used to match additional partons in the matrix-element calculations
to the parton-shower description. No additional partons are included in the generation
of events for the single top quark production process, as such inclusion would contain
contributions from the top quark pair production process. A systematic variation in the
normalization of the single top production process by 10% is considered in order to account
for the differences in the generation of additional radiation of the two signal production
modes. The Lagrangian terms from eq. (1.1) are implemented by means of the FeynRules
package [19] using the universal FeynRules output format [20]. The complex chiral
parameters are fixed to fR
Hq = 1 and fL
Hq = 0. JHEP06(2018)102 The SM top quark pair production is the dominant background process and is simulated
to next-to-leading order (NLO) using powheg v2 [21–24]. The predicted cross section for
this process is 832 +20
−29 (scale) ± 35(PDF) pb, as calculated with the Top++ 2.0 program
at next-to-next-to-leading order (NNLO), including soft-gluon resummation to next-to-
next-to-leading-log order (see ref. [25] and references therein), and assuming a top quark
mass of mt = 172.5 GeV. Two systematic uncertainties that are shown in the prediction
are considered. These are independent variations of the factorization and renormalization
scales, µF and µR, and variations of the PDF and αs. Single top quark production in the t channel is simulated with powheg v2 in the
four-flavour scheme, while events for single top quark production in association with W
bosons are generated with powheg v1 in the five-flavour scheme (5FS). The predicted
NLO cross sections are 217+9
−8 [26, 27] and 71.7 ± 3.9 pb [28], respectively. Single top quark
production in the s channel is done at NLO with the MadGraph5 amc@nlo generator
in 5FS with a predicted cross section of 10.3 ± 0.4 pb. The uncertainties in the quoted
cross sections correspond to independent variations of µF and µR, as well as to variations
of the PDF and αs. 2
The CMS detector The central feature of the CMS detector is a superconducting solenoid of 6 m internal
diameter, providing a magnetic field of 3.8 T. Within the solenoid volume are a silicon
pixel and strip tracker, a lead tungstate crystal electromagnetic calorimeter (ECAL), and
a brass and scintillator hadron calorimeter (HCAL), each composed of a barrel and two – 2 – endcap sections. Forward calorimeters extend the pseudorapidity coverage provided by the
barrel and endcap detectors. Muons are measured in gas-ionization detectors embedded
in the steel flux-return yoke outside the solenoid. A more detailed description of the
CMS detector, together with a definition of the coordinate system used and the relevant
kinematic variables, can be found in ref. [15]. 3
Monte Carlo simulation Small contributions to the overall predicted background arise from
several additional processes: W boson production and the associated production of tt
with W and Z, both generated with MadGraph5 amc@nlo, and from Drell-Yan and the
associated production of tt with a Higgs boson generated with the MadGraph5 amc@nlo
and powheg v1 [29], respectively. In the simulation of signal and background processes, the initial- and final-state ra-
diation (ISR and FSR), as well as the fragmentation and hadronization of quarks, are
modeled using pythia 8.212 [30] with the underlying event tune CUETP8M1 [31]. For tt – 3 – generation, the first emission is done at the matrix-element level with powheg v2. Gen-
eration of tt and single top quark production in the t channel uses the underlying event
tune CUETP8M2T4 [32]. In the generation of all background processes the NNPDF3.0
PDF [33] set is used. The detector response is simulated using Geant4 v9.4 [34]. In order to model the effect
of multiple interactions per event crossing (pileup), generated minimum bias events were
added to the simulated data. The number of extra multiple interactions were matched to
agree with the rate observed in data. The number of pileup interactions in data is estimated
from the measured bunch-to-bunch instantaneous luminosity and the total inelastic cross
section (69.2 mb) [14]. JHEP06(2018)102 4
Event selection The particle-flow (PF) algorithm [35] reconstructs and identifies each individual particle
with an optimized combination of information from the various elements of the CMS de-
tector. The energy of photons is directly obtained from the ECAL measurement, corrected
for zero-suppression effects. The energy of electrons is determined from a combination of
the electron momentum at the primary interaction vertex as determined by the tracker,
the energy of the corresponding ECAL cluster, and the energy sum of all bremsstrahlung
photons spatially compatible with originating from the electron track. The momentum of
muons is obtained from the curvature of the corresponding track. The energy of charged
hadrons is determined from a combination of their momentum measured in the tracker and
the matching ECAL and HCAL energy deposits, corrected for zero-suppression effects and
for the response function of the calorimeters to hadronic showers. Finally, the energy of
neutral hadrons is obtained from the corresponding corrected ECAL and HCAL energy. Jets are reconstructed by clustering PF candidates using the anti-kT algorithm [36, 37]
with a distance parameter of 0.4. The jet momentum is determined as the vectorial sum
of all particle momenta in the jet, and is found from simulation to be within 5 to 10%
of the true momentum over the whole transverse momentum (pT) spectrum and detec-
tor acceptance [38]. An offset correction is applied to jet energies to take into account
the contribution from pileup. Jet energy corrections are derived from simulation and are
confirmed with in situ measurements of the energy balance in dijet, multijet, γ+jet, and
leptonic Z+jet events. Additional selection criteria are applied to each event to remove
spurious jet-like features originating from isolated noise patterns in certain HCAL regions. The missing transverse momentum (⃗pmiss
T
) in an event is defined as the magnitude of the
transverse projection of the vector sum of the momenta of all reconstructed PF candidates
in an event. The reconstructed vertex with the largest value of summed physics-object p2
T is taken
to be the primary pp interaction vertex. The physics objects are the jets, clustered using
the jet finding algorithm [36, 37] with the tracks assigned to the vertex as inputs, and the
associated ⃗pmiss
T
, taken as the negative vector pT sum of those jets, to represent the neutral
particles. – 4 – This analysis selects events with exactly one isolated lepton (electron or muon). 4
Event selection Events
with one electron (muon) are recorded using a trigger that required at least one electron
(muon) with pT > 32 (24) GeV selected within the detector acceptance (|η| < 2.1). Electron
(muon) candidates are selected offline with |η| < 2.1 with pT > 35 (30) GeV. Electrons
that are reconstructed in the transition region between the barrel and endcap regions of
the ECAL, 1.44 < |η| < 1.57, are removed. Leptons are required to be isolated in terms
of a relative isolation variable, Irel. This variable is defined as the ratio of the scalar pT
sum of photons, charged hadrons, and neutral hadrons within a cone of angular radius
∆R =
√
(∆η)2 + (∆φ)2 = 0.3 (0.4) of the reconstructed lepton candidate, where φ is
azimuthal angle in radians, to the lepton pT. This isolation variable only includes the
charged hadrons that emerge from the same vertex as the selected lepton and is corrected
for energy deposits from neutral particles produced in pileup interactions. For electron
(muon) candidates, Irel must be less than 0.06 (0.15). In order to suppress background
processes with multilepton final states, events with additional leptons passing the looser
isolation requirement of Irel < 0.25 and pT > 10 GeV are rejected. JHEP06(2018)102 At least three jets are required to be present in the event with pT > 30 GeV and
|η| < 2.4. As signal events contain three b quarks produced in the final state at the tree
level, we require at least two jets are identified as b quark jets by the combined secondary
vertex v2 (CSVv2) b tagging algorithm [39]. This requirement corresponds to the selection
of jets with the CSVv2 discriminant value greater than 0.85, and provides a b jet efficiency
of ≈70%, with a misidentification rate for c jets and jets originating from light quarks and
gluons of ≈10% and ≈1%, respectively. 5
Event reconstruction and multivariate analysis In order to optimize sensitivity to the signal event selection, events are split into five cate-
gories based on the total number of reconstructed jets and on the number of b-tagged jets. Categories with exactly three jets of which two or three are identified as b jets are denoted
as b2j3 and b3j3, respectively. Similarly, categories with at least four jets of which two,
three, or four are identified as b jets are specified as b2j4, b3j4, and b4j4, respectively The
longitudinal momentum of the neutrino is determined by assigning ⃗pmiss
T
to the neutrino,
and constraining the ℓν mass to the known mass of the W boson. With the use of the
energy and momenta of all particles, a full kinematic reconstruction of the event is per-
formed for several signal and background hypotheses: ST, TT, and background tt events,
where one of the top quarks decays semileptonically, and the other one hadronically. The
reconstruction is performed for all possible permutations of the b-tagged jets to be associ-
ated with the decay products of the Higgs boson or the top quark, and both solutions for
the longitudinal momentum of the neutrino are considered. The reconstructed kinematic
variables for each permutation are then fed into a multivariate analysis that uses a boosted
decision tree (BDT) [40] approach, as implemented in the toolkit for multivariate analysis
TMVA [41]. The input BDT variables that are used for the ST and TT hypotheses cor-
respond to the reconstructed invariant mass of two b jets associated with the Higgs boson
decay, the reconstructed invariant mass of a b jet (mbb), lepton and neutrino associated – 5 – with the top quark decay (m(tℓ)), its transverse momentum (pT(tℓ)), ∆R between the
reconstructed Higgs boson and the top quark. In case of the hypothesis of the background
t¯t events the following variables are used: m(tℓ), m(th), ∆R(tℓ, th), and pT(tℓ), where th
corresponds to the reconstructed top quark hadronic decay from one b-tagged and two
non b-tagged jets. The BDT classifier is trained to distinguish the correct from the wrong
b jet assignments. The training and validation of the BDT is performed on statistically
independent simulated samples. All reconstructed b jets in the event are considered, and
the permutation with the highest BDT score is chosen as the correct one. 5
Event reconstruction and multivariate analysis The measured
algorithm efficiency for correct assignment of the b-tagged jets to the jets reconstructed at
generator level after applying the analysis selection criteria is ≈75%. JHEP06(2018)102 Kinematic variables from the event reconstruction are used to construct several BDTs
to suppress backgrounds. The BDTs are trained for each jet multiplicity category to iden-
tify signal events that are generated either for κHut (Hut) or κHct (Hct) coupling against
the sum of all background events. Separate trainings of the BDT for Hut and Hct are
done in order to take into account the differences in kinematic properties of the recon-
structed objects in the ST production mode, as well as the differences in the measured
b tagging efficiencies for a charm and an up quark in the TT production channel. The
most important variables that discriminate between signal and background events are: the
charge of the lepton (considered only for the BDT that uses Hut signal events), the CSVv2
discriminant value of the b jet with the lowest pT from the Higgs boson decay, mbb, and
the output discriminant value of the BDT used in the b jet assignment procedure. Distri-
butions for these variables in data and MC simulation in the b3j3 category are presented
in figure 2. The b4j4 category is not considered for Hut due to negligible improvement in
the final sensitivity. The simulated tt background events are split into subcategories defined by the flavor
of additional particle-level jets produced in association with the top quark pair. These
classes are referred to as tt+bb, tt+cc, and tt+lf, (where lf stands for light flavor). The
tt+lf category includes events where no additional pair of b or c jets occurs. The other
background processes are summed up and shown together in the prediction. The final observable used to extract signal events is defined as the BDT score distri-
bution in each jet category corresponding to either Hut or Hct signal training. Figures 3
and 4 show the comparison between data and simulation for this observable after the fit to
data with all background processes constrained to the SM expectation. 6
Estimation of systematic uncertainties Sources of systematic uncertainty that affect both the normalization and shape of the
predicted signal and background events are considered in the analysis. All systematic
uncertainties are treated as nuisance parameters in the derivation of the exclusion limit. The dominant systematic uncertainty arises from the application of the b tagging
requirement. The shape of the CSVv2 discriminant, the b tagging efficiency, and the
misidentification rate in simulation are corrected to reproduce the data distributions [39]. The uncertainties that are associated with these correction factors are the statistical uncer- – 6 – Events
2000
4000
6000
8000
10000
12000
(13 TeV)
-1
35.9 fb
CMS
b3j3
Lepton charge
-1
0
1
Data / MC
0.5
1
1.5
Data
+lf
tt
c
+c
tt
b
+b
tt
other
=1)x3.9
Hut
κ
ST(
=1)x20
Hct
κ
ST(
=1)x2.3
Hut
κ
TT(
=1)x1.7
Hct
κ
TT(
Events / 0.01
200
400
600
800
1000
1200
(13 TeV)
-1
35.9 fb
CMS
b3j3
b jet CSVv2 discriminant
0.85
0.9
0.95
1
Data / MC
0.5
1
1.5
Data
+lf
tt
c
+c
tt
b
+b
tt
other
=1)x3.9
Hut
κ
ST(
=1)x20
Hct
κ
ST(
=1)x2.3
Hut
κ
TT(
=1)x1.7
Hct
κ
TT(
Events / 8.33 GeV
500
1000
1500
2000
2500
(13 TeV)
-1
35.9 fb
CMS
b3j3
[GeV]
b
b
m
0
50
100
150
200
250
Data / MC
0.5
1
1.5
Data
+lf
tt
c
+c
tt
b
+b
tt
other
=1)x3.9
Hut
κ
ST(
=1)x20
Hct
κ
ST(
=1)x2.3
Hut
κ
TT(
=1)x1.7
Hct
κ
TT(
Events / 0.07
500
1000
1500
2000
2500
(13 TeV)
-1
35.9 fb
CMS
b3j3
BDT discriminant
1
−
0.5
−
0
0.5
1
Data / MC
0.5
1
1.5
Data
+lf
tt
c
+c
tt
b
+b
tt
other
=1)x3.9
Hut
κ
ST(
=1)x20
Hct
κ
ST(
=1)x2.3
Hut
κ
TT(
=1)x1.7
Hct
κ
TT(
Figure 2. Comparison between data and simulation for the most discriminating BDT input vari-
ables in the b3j3 category: lepton charge (upper left), CSVv2 discriminant value for one of the
reconstructed b jets assigned to Higgs boson decay (upper right), reconstructed invariant mass of
two b jets associated with the Higgs boson decay (lower left), and the maximum BDT discriminant
value from the b jet assignment procedure (lower right). The last bin in the distribution for the
reconstructed mass of the Higgs boson includes the overflows. 6
Estimation of systematic uncertainties The shaded area corresponds to the
total uncertainty in the predicted background. The data-to-simulation ratio is also shown. The
distributions for the signal processes are normalized to the total number of events in the predicted
background to ease the comparison of the shapes of the distributions. Events
2000
4000
6000
8000
10000
12000
(13 TeV)
-1
35.9 fb
CMS
b3j3
Lepton charge
-1
0
1
Data / MC
0.5
1
1.5
Data
+lf
tt
c
+c
tt
b
+b
tt
other
=1)x3.9
Hut
κ
ST(
=1)x20
Hct
κ
ST(
=1)x2.3
Hut
κ
TT(
=1)x1.7
Hct
κ
TT( Events / 0.01
200
400
600
800
1000
1200
(13 TeV)
-1
35.9 fb
CMS
b3j3
b jet CSVv2 discriminant
0.85
0.9
0.95
1
Data / MC
0.5
1
1.5
Data
+lf
tt
c
+c
tt
b
+b
tt
other
=1)x3.9
Hut
κ
ST(
=1)x20
Hct
κ
ST(
=1)x2.3
Hut
κ
TT(
=1)x1.7
Hct
κ
TT( JHEP06(2018)102 p
g
Events / 8.33 GeV
500
1000
1500
2000
2500
(13 TeV)
-1
35.9 fb
CMS
b3j3
[GeV]
b
b
m
0
50
100
150
200
250
Data / MC
0.5
1
1.5
Data
+lf
tt
c
+c
tt
b
+b
tt
other
=1)x3.9
Hut
κ
ST(
=1)x20
Hct
κ
ST(
=1)x2.3
Hut
κ
TT(
=1)x1.7
Hct
κ
TT( Events / 0.07
500
1000
1500
2000
2500
(13 TeV)
-1
35.9 fb
CMS
b3j3
BDT discriminant
1
−
0.5
−
0
0.5
1
Data / MC
0.5
1
1.5
Data
+lf
tt
c
+c
tt
b
+b
tt
other
=1)x3.9
Hut
κ
ST(
=1)x20
Hct
κ
ST(
=1)x2.3
Hut
κ
TT(
=1)x1.7
Hct
κ
TT( Events / 0.07 Figure 2. Comparison between data and simulation for the most discriminating BDT input vari-
ables in the b3j3 category: lepton charge (upper left), CSVv2 discriminant value for one of the
reconstructed b jets assigned to Higgs boson decay (upper right), reconstructed invariant mass of
two b jets associated with the Higgs boson decay (lower left), and the maximum BDT discriminant
value from the b jet assignment procedure (lower right). The last bin in the distribution for the
reconstructed mass of the Higgs boson includes the overflows. The shaded area corresponds to the
total uncertainty in the predicted background. The data-to-simulation ratio is also shown. 6
Estimation of systematic uncertainties The
distributions for the signal processes are normalized to the total number of events in the predicted
background to ease the comparison of the shapes of the distributions. tainty due to the limited data sample from which the correction factors were derived, and
the systematic uncertainty arising from the purity estimate of the sample as predicted by
simulation. The overall effect of this systematic uncertainty leads to a variation of ≈8–30%
in simulated event yields, with the largest effect observed in event categories with a large
number of b-tagged jets. The uncertainty associated with the choice of renormalization and factorization scales
in the matrix element is estimated by changing each scale separately by a factor of 1/2
and 2. To estimate the systematic uncertainty at the parton-shower level, several special
simulated samples of events are considered, where the scales used to determine the ISR
and FSR emissions are varied. The uncertainty associated with the choice of PDF is
estimated by using several PDFs and assigning the maximum differences as the quoted
uncertainty, following the PDF4LHC prescription with the MSTW2008 68% CL NNLO, – 7 – Figure 3. The BDT discriminant distributions for different jet categories for Hut training after the
fit to data. All background processes are constrained to the SM expectation in the fit. The shaded
area corresponds to the total uncertainty in the predicted background. The data-to-simulation
ratio is also shown. The distributions for the signal processes are normalized to the total number
of events in the predicted background to ease the comparison of the shapes of the distributions. JHEP06(2018)102 Figure 3. The BDT discriminant distributions for different jet categories for Hut training after the
fit to data. All background processes are constrained to the SM expectation in the fit. The shaded
area corresponds to the total uncertainty in the predicted background. The data-to-simulation
ratio is also shown. The distributions for the signal processes are normalized to the total number
of events in the predicted background to ease the comparison of the shapes of the distributions. CT10 NNLO, and NNPDF2.3 5f FFN PDF sets (see ref. [42] and references therein, as
well as refs. [13, 43, 44]). The overall uncertainty associated with the simulation of the
background processes contributes up to ≈20% in the variation of event yields. 6
Estimation of systematic uncertainties Following the prescription in powheg [32], the matching of the high-pT partons, from
matrix-element calculations and parton-shower emission, is regulated by damping the emis-
sion by the factor m2
t/(p2
T + m2
t). Additional simulated samples for tt are used that cor-
respond to the variation of this factor within the considered uncertainty. For the tt and
single top quark t-channel simulated samples the additional systematic uncertainties as-
sociated with the amount of multiparton interactions and color reconnection [45, 46] are
considered. These uncertainties were determined by varying them according to the uncer-
tainties reported for the underlying event tune CUETP8M2T4, and lead to a systematic
effect of ≈1–5%. The uncertainty associated with the calibration of the jet energy scale and the jet
energy resolution contributes up to ≈8% in the variation of the final event yields [47]. The
identification, isolation, and trigger efficiency correction uncertainties for reconstructed – 8 – Figure 4. The BDT discriminant distributions for different jet categories for Hct training after the
fit to data. All background processes are constrained to the SM expectation in the fit. The shaded
area corresponds to the total uncertainty in the predicted background. The data-to-simulation
ratio is also shown. The distributions for the signal processes are normalized to the total number
of events in the predicted background to ease the comparison of the shapes of the distributions. JHEP06(2018)102 Figure 4. The BDT discriminant distributions for different jet categories for Hct training after the
fit to data. All background processes are constrained to the SM expectation in the fit. The shaded
area corresponds to the total uncertainty in the predicted background. The data-to-simulation
ratio is also shown. The distributions for the signal processes are normalized to the total number
of events in the predicted background to ease the comparison of the shapes of the distributions. 6
Estimation of systematic uncertainties – 9 – b2j3
b2j4
b3j3
b3j4
Data
365 890
575 500
13 481
53 352
tt+bb
8 880 ± 3 641
30 157 ± 5 127
1 214 ± 510
11 668 ± 1 750
tt+cc
26 035 ± 11 195
81 959 ± 18 031
1 281 ± 576
9 753 ± 2 243
tt+lf
270 989 ± 13 820
410 028 ± 16 401
9 104 ± 674
27 079 ± 1 733
other
58 991 ± 6 489
51 845 ± 6 221
1 616 ± 356
4 269 ± 768
Total
364 895 ± 22 623
573 989 ± 25 256
13 215 ± 1 255
52 769 ± 3 430
Table 1. Number of events in each category together with its total relative uncertainty as obtained
from the fit to data for Hut. Table 1. Number of events in each category together with its total relative uncertainty as obtained
from the fit to data for Hut. JHEP06(2018)102 leptons contribute up to 0.5% of the total uncertainty in the predicted yield. An uncertainty
of 2.5% is assigned to the measured integrated luminosity value of the considered data
sample [14]. The number of simulated pileup events is corrected to match the measured number of
events in data. The uncertainty on the total inelastic cross section is taken as 4.6%. Its
overall contribution to the total systematic uncertainty is found to be negligible. The pT spectrum of individual top quarks in data is found to be softer than predicted
by the simulation. A correction for the top quark pT spectrum in simulation is applied
and the difference between the initial and the corrected shapes is taken as an additional
systematic uncertainty [48]. This uncertainty also has a negligible impact on the final
distributions. Additionally, a systematic uncertainty of 50% in the predicted cross sections for tt+bb
and tt+cc processes is assumed [49, 50]. 7
Results A comparison between the number of selected events in data and simulation is shown in
tables 1 and 2. A 95% CL upper limit is computed for the production cross section of tH
FCNC events times branching fractions of top quark semileptonic decay and Higgs boson
decay to b quarks that uses the asymptotic approximation of the CLs method [51, 52]. The profile likelihood ratio test statistic [53] is defined as q(µ) = −2 ln(L(µ, ˆθµ)/L(ˆµ, ˆθ)),
where L is a binned likelihood function, µ is a signal strength modifier, θ is a set of
nuisance parameters, ˆθµ is a set of nuisance parameters that maximize L for a given µ,
ˆµ and ˆθ are the values of the corresponding parameters which simultaneously maximize
L. Uncertainties due to normalization are included through nuisance parameters with
log-normal prior distributions, while shape uncertainties are included with Gaussian prior
distributions. The expected and observed 95% CL upper limits are derived on the signal
production cross section separately for each event category, as well as for their combination
(figure 5). In the latter case, a simultaneous binned maximum-likelihood fit to all categories
is performed. The fit takes into account the statistical and systematic uncertainties in the
final BDT score distributions in each jet category. The resultant observed (expected) 95% CL exclusion limits on top quark FCNC decay
branching fractions are B(t →uH) < 0.47% (0.34%) and B(t →cH) < 0.47% (0.44%). – 10 – b2j3
b2j4
b3j3
b3j4
comb
[pb]
σ
0
5
10
15
20
95% CL upper limits
Median expected
68% expected
95% expected
Observed
CMS
(13 TeV)
-1
35.9 fb
Hut
b2j3
b2j4
b3j3
b3j4
b4j4
comb
[pb]
σ
0
5
10
15
20
95% CL upper limits
Median expected
68% expected
95% expected
Observed
CMS
(13 TeV)
-1
35.9 fb
Hct
Figure 5. Excluded signal cross section at 95% CL per event category for Hut (left) and Hct
(right). b2j3
b2j4
b3j3
b3j4
b4j4
comb
[pb]
σ
0
5
10
15
20
95% CL upper limits
Median expected
68% expected
95% expected
Observed
CMS
(13 TeV)
-1
35.9 fb
Hct b2j3
b2j4
b3j3
b3j4
comb
[pb]
σ
0
5
10
15
20
95% CL upper limits
Median expected
68% expected
95% expected
Observed
CMS
(13 TeV)
-1
35.9 fb
Hut JHEP06(2018)102 Figure 5. Excluded signal cross section at 95% CL per event category for Hut (left) and Hct
(right). 7
Results uH) [%]
→
(t
B
0
0.1
0.2
0.3
0.4
0.5
0.6
cH) [%]
→
(t
B
0
0.2
0.4
0.6
0.8
1
95% CL upper limits
Median expected
68% expected
95% expected
Observed
CMS
(13 TeV)
-1
35.9 fb
Figure 6. Upper limits on B(t →uH) and B(t →cH) at 95% CL. uH) [%]
→
(t
B
0.5
0.6 Figure 6. Upper limits on B(t →uH) and B(t →cH) at 95% CL. Hut
κ
0
0.05
0.1
0.15
0.2
Hct
κ
0
0.1
0.2
0.3
0.4
0.5
95% CL upper limits
Median expected
68% expected
95% expected
Observed
CMS
(13 TeV)
-1
35.9 fb
Figure 7. Upper limits on κHut and κHct at 95% CL. Figure 7. Upper limits on κHut and κHct at 95% CL. – 11 – b2j3
b2j4
b3j3
b3j4
b4j4
Data
365 890
575 500
13 481
53 352
2 764
tt+bb
10 176 ± 1 933
34 174 ± 3 759
1 367 ± 273
12 897 ± 1 058
1 517 ± 129
tt+cc
33 210 ± 11 956
102 186 ± 15 328
1 674 ± 619
12 280 ± 1 842
521 ± 104
tt+lf
258 679 ± 8 795
385 395 ± 10 791
8 349 ± 451
24 083 ± 1 132
383 ± 69
other
62 887 ± 5 723
52 134 ± 6 256
1 742 ± 401
3 513 ± 562
262 ± 50
Total
364 952 ± 16 788
573 889 ± 18 364
13 132 ± 959
52 773 ± 2 322
2 682 ± 185
Table 2. Number of events in each category together with its total relative uncertainty as obtained
from the fit to data for Hct. Table 2. Number of events in each category together with its total relative uncertainty as obtained
from the fit to data for Hct. µ
1
−
0.5
−
0
0.5
1
1.5
2
2.5
3
μb2j3
μb2j4
μb3j3
μb3j4
category
µ
comb. µ
CMS
(13 TeV)
-1
35.9 fb
Hut
µ
1
−
0.5
−
0
0.5
1
1.5
2
2.5
3
μb2j3
μb2j4
μb3j3
μb3j4
μb4j4
category
µ
comb. µ
CMS
(13 TeV)
-1
35.9 fb
Hct
Figure 8. The best fit signal strength (µ) for Hut (left) and Hct (right), which is restricted to
positive values in the fit. 7
Results µ
1
−
0.5
−
0
0.5
1
1.5
2
2.5
3
μb2j3
μb2j4
μb3j3
μb3j4
μb4j4
category
µ
comb. µ
CMS
(13 TeV)
-1
35.9 fb
Hct µ
1
−
0.5
−
0
0.5
1
1.5
2
2.5
3
μb2j3
μb2j4
μb3j3
μb3j4
category
µ
comb. µ
CMS
(13 TeV)
-1
35.9 fb
Hut JHEP06(2018)102 µ Figure 8. The best fit signal strength (µ) for Hut (left) and Hct (right), which is restricted to
positive values in the fit. These upper limits on the branching fractions can be translated into upper limits on the
coupling strengths using the relations: These upper limits on the branching fractions can be translated into upper limits on the
coupling strengths using the relations: κ2
Hut = B(t →uH) Γt
ΓHut
,
κ2
Hct = B(t →cH) Γt
ΓHct
,
(7.1) (7.1) where the total top quark width is Γt = 1.32 GeV [54], and the partial width for the FCNC
decay process of the top quark is ΓHut = ΓHct = 0.184 GeV for κHut = κHct = 1. The
resultant limits on the coupling strengths are κHut < 0.18 (0.16) and κHct < 0.18 (0.18). These limits are very competitive to the CMS result with the combination of various
channels at 8 TeV [12], while the ATLAS result with the analysis of the H →γγ decay
at 13 TeV [11] represents the best limits to date. The measured one-dimensional exclusion
limits are also interpreted for the scenario of the non-vanishing FCNC couplings via a linear
interpolation. The results for two-dimensional limits on top quark FCNC decay branching
fractions and coupling strengths are presented in figure 6 and 7, respectively. We define a
signal strength parameter as µ = σ/σsig, where σ is the cross section excluded at 95% CL
and σsig is the predicted cross section for signal. A maximum likelihood fit is performed
for the signal strength, and is shown in figure 8. Inclusion of the associated production of a
single top quark with a Higgs boson in this study provides a ≈20% relative improvement in
the expected upper limit on B(t →uH) with respect to the results obtained in an analysis
of only tt events with top quark FCNC decays. – 12 – 8
Summary A search for flavor-changing neutral currents in events with a top quark and the Higgs
boson, corresponding to a data sample of 35.9 fb−1 collected in proton-proton collisions at
√s = 13 TeV, is presented. This is the first search to probe tH flavor-changing neutral
current couplings in both associated production of a top quark with the Higgs boson
and in top quark decays. Observed (expected) upper limits at 95% confidence level are
set on the branching fractions of top quark decays, B(t →uH) < 0.47% (0.34%) and
B(t →cH) < 0.47% (0.44%). These results provide a significant improvement over the
previous limits set by CMS in the H →bb channel, as well as represent the best limits for
B(t →uH) at CMS. JHEP06(2018)102 Acknowledgments We congratulate our colleagues in the CERN accelerator departments for the excellent
performance of the LHC and thank the technical and administrative staffs at CERN and
at other CMS institutes for their contributions to the success of the CMS effort. In ad-
dition, we gratefully acknowledge the computing centres and personnel of the Worldwide
LHC Computing Grid for delivering so effectively the computing infrastructure essential
to our analyses. Finally, we acknowledge the enduring support for the construction and
operation of the LHC and the CMS detector provided by the following funding agencies:
BMWFW and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ,
and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COL-
CIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus); SENESCYT (Ecuador);
MoER, ERC IUT, and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland);
CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece);
OTKA and NIH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN
(Italy); MSIP and NRF (Republic of Korea); LAS (Lithuania); MOE and UM (Malaysia);
BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MBIE (New
Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna);
MON, RosAtom, RAS, RFBR and RAEP (Russia); MESTD (Serbia); SEIDI, CPAN, PCTI
and FEDER (Spain); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter,
IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU and SFFR
(Ukraine); STFC (United Kingdom); DOE and NSF (U.S.A.). Individuals have received support from the Marie-Curie programme and the European
Research Council and Horizon 2020 Grant, contract No. 675440 (European Union); the
Leventis Foundation; the A. P. Acknowledgments Sloan Foundation; the Alexander von Humboldt Founda-
tion; the Belgian Federal Science Policy Office; the Fonds pour la Formation `a la Recherche
dans l’Industrie et dans l’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door
Wetenschap en Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports
(MEYS) of the Czech Republic; the Council of Science and Industrial Research, India;
the HOMING PLUS programme of the Foundation for Polish Science, cofinanced from
European Union, Regional Development Fund, the Mobility Plus programme of the Min- – 13 – istry of Science and Higher Education, the National Science Center (Poland), contracts
Harmonia 2014/14/M/ST2/00428, Opus 2014/13/B/ST2/02543, 2014/15/B/ST2/03998,
and 2015/19/B/ST2/02861, Sonata-bis 2012/07/E/ST2/01406; the National Priorities Re-
search Program by Qatar National Research Fund; the Programa Severo Ochoa del Prin-
cipado de Asturias; the Thalis and Aristeia programmes cofinanced by EU-ESF and the
Greek NSRF; the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn
University and the Chulalongkorn Academic into Its 2nd Century Project Advancement
Project (Thailand); the Welch Foundation, contract C-1845; and the Weston Havens Foun-
dation (U.S.A.). JHEP06(2018)102 Open Access. This article is distributed under the terms of the Creative Commons
Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in
any medium, provided the original author(s) and source are credited. References [1] ATLAS collaboration, Observation of a new particle in the search for the standard model
Higgs boson with the ATLAS detector at the LHC, Phys. Lett. B 716 (2012) 1
[arXiv:1207.7214] [INSPIRE]. [2] CMS collaboration, Observation of a new boson at a mass of 125 GeV with the CMS
experiment at the LHC, Phys. Lett. B 716 (2012) 30 [arXiv:1207.7235] [INSPIRE]. [3] CMS collaboration, Observation of a new boson with mass near 125 GeV in pp collisions at
√s = 7 and 8 TeV, JHEP 06 (2013) 081 [arXiv:1303.4571] [INSPIRE]. [3] CMS collaboration, Observation of a new boson with mass near 125 GeV in pp collisions at
√s = 7 and 8 TeV, JHEP 06 (2013) 081 [arXiv:1303.4571] [INSPIRE]. [4] ATLAS, CMS collaboration, Measurements of the Higgs boson production and decay rates
and constraints on its couplings from a combined ATLAS and CMS analysis of the LHC pp
collision data at √s = 7 and 8 TeV, JHEP 08 (2016) 045 [arXiv:1606.02266] [INSPIRE]. [4] ATLAS, CMS collaboration, Measurements of the Higgs boson production and decay rates
and constraints on its couplings from a combined ATLAS and CMS analysis of the LHC pp
collision data at √s = 7 and 8 TeV, JHEP 08 (2016) 045 [arXiv:1606.02266] [INSPIRE]. [5] S.L. Glashow, J. Iliopoulos and L. Maiani, Weak Interactions with Lepton-Hadron Symmetry,
Phys. Rev. D 2 (1970) 1285 [INSPIRE]. [6] G. Eilam, J.L. Hewett and A. Soni, Rare decays of the top quark in the standard and two
Higgs doublet models, Phys. Rev. D 44 (1991) 1473 [Erratum ibid. D 59 (1999) 039901]
[INSPIRE]. [7] B. Mele, S. Petrarca and A. Soddu, A New evaluation of the t →cH decay width in the
standard model, Phys. Lett. B 435 (1998) 401 [hep-ph/9805498] [INSPIRE]. [8] J.A. Aguilar-Saavedra, Top flavor-changing neutral interactions: theoretical expectations and
experimental detection, Acta Phys. Polon. B 35 (2004) 2695 [hep-ph/0409342] [INSPIRE]. [9] F. Larios, R. Martinez and M.A. Perez, New physics effects in the flavor-changing neutral
couplings of the top quark, Int. J. Mod. Phys. A 21 (2006) 3473 [hep-ph/0605003] [INSPIRE]. [10] ATLAS collaboration, Search for flavour-changing neutral current top quark decays t →Hq
in pp collisions at √s = 8 TeV with the ATLAS detector, JHEP 12 (2015) 061
[arXiv:1509.06047] [INSPIRE]. References [11] ATLAS collaboration, Search for top quark decays t →qH, with H →γγ, in √s = 13 TeV
pp collisions using the ATLAS detector, JHEP 10 (2017) 129 [arXiv:1707.01404] [INSPIRE]. [11] ATLAS collaboration, Search for top quark decays t →qH, with H →γγ, in √s = 13 TeV
pp collisions using the ATLAS detector, JHEP 10 (2017) 129 [arXiv:1707.01404] [INSPIRE]. – 14 – [12] CMS collaboration, Search for top quark decays via Higgs-boson-mediated flavor-changing
neutral currents in pp collisions at √s = 8 TeV, JHEP 02 (2017) 079 [arXiv:1610.04857]
[INSPIRE]. [13] R.D. Ball et al., Parton distributions with LHC data, Nucl. Phys. B 867 (2013) 244
[arXiv:1207.1303] [INSPIRE]. [14] CMS collaboration, CMS luminosity measurements for the 2016 data taking period,
CMS-PAS-LUM-17-001 (2017). [15] CMS collaboration, The CMS experiment at the CERN LHC, 2008 JINST 3 S08004
[INSPIRE]. JHEP06(2018)102 [16] J. Alwall et al., The automated computation of tree-level and next-to-leading order
differential cross sections and their matching to parton shower simulations, JHEP 07 (2014)
079 [arXiv:1405.0301] [INSPIRE]. [17] M.L. Mangano, M. Moretti, F. Piccinini and M. Treccani, Matching matrix elements and
shower evolution for top-quark production in hadronic collisions, JHEP 01 (2007) 013
[hep-ph/0611129] [INSPIRE]. [18] J. Alwall et al., Comparative study of various algorithms for the merging of parton showers
and matrix elements in hadronic collisions, Eur. Phys. J. C 53 (2008) 473
[arXiv:0706.2569] [INSPIRE]. [19] A. Alloul et al., FeynRules 2.0 — A complete toolbox for tree-level phenomenology, Comput. Phys. Commun. 185 (2014) 2250 [arXiv:1310.1921] [INSPIRE]. [20] C. Degrande et al., UFO - The Universal FeynRules Output, Comput. Phys. Commun. 183
(2012) 1201 [arXiv:1108.2040] [INSPIRE]. [21] P. Nason, A New method for combining NLO QCD with shower Monte Carlo algorithms,
JHEP 11 (2004) 040 [hep-ph/0409146] [INSPIRE]. [22] S. Frixione, P. Nason and C. Oleari, Matching NLO QCD computations with Parton Shower
simulations: the POWHEG method, JHEP 11 (2007) 070 [arXiv:0709.2092] [INSPIRE]. [23] S. Alioli, P. Nason, C. Oleari and E. Re, A general framework for implementing NLO
calculations in shower Monte Carlo programs: the POWHEG BOX, JHEP 06 (2010) 043
[arXiv:1002.2581] [INSPIRE]. [24] S. Alioli, S.-O. Moch and P. Uwer, Hadronic top-quark pair-production with one jet and
parton showering, JHEP 01 (2012) 137 [arXiv:1110.5251] [INSPIRE]. [25] M. Czakon and A. Mitov, Top++: a program for the calculation of the top-pair cross-section
at hadron colliders, Comput. Phys. Commun. 185 (2014) 2930 [arXiv:1112.5675] [INSPIRE]. [26] M. References Aliev, et al., HATHOR: HAdronic Top and Heavy quarks crOss section calculatoR,
Comput. Phys. Commun. 182 (2011) 1034 [arXiv:1007.1327] [INSPIRE]. [27] P. Kant et al., HatHor for single top-quark production: Updated predictions and uncertainty
estimates for single top-quark production in hadronic collisions, Comput. Phys. Commun. 191 (2015) 74 [arXiv:1406.4403] [INSPIRE]. [28] N. Kidonakis, Two-loop soft anomalous dimensions for single top quark associated production
with a W −or H−, Phys. Rev. D 82 (2010) 054018 [arXiv:1005.4451] [INSPIRE]. [29] L. Barze et al., Neutral current Drell-Yan with combined QCD and electroweak corrections in
the POWHEG BOX, Eur. Phys. J. C 73 (2013) 2474 [arXiv:1302.4606] [INSPIRE]. – 15 – [30] T. Sj¨ostrand, S. Mrenna and P.Z. Skands, A brief introduction to PYTHIA 8.1, Comput. Phys. Commun. 178 (2008) 852 [arXiv:0710.3820] [INSPIRE]. [31] CMS collaboration, Event generator tunes obtained from underlying event and multiparton
scattering measurements, Eur. Phys. J. C 76 (2016) 155 [arXiv:1512.00815] [INSPIRE]. [32] CMS collaboration, Investigations of the impact of the parton shower tuning in PYTHIA 8
in the modelling of t¯t at √s = 8 and 13 TeV, CMS-PAS-TOP-16-021 (2016). [33] NNPDF collaboration, R.D. Ball et al., Parton distributions for the LHC Run II, JHEP 04
(2015) 040 [arXiv:1410.8849] [INSPIRE]. [34] GEANT4 collaboration, S. Agostinelli et al., GEANT4 — a simulation toolkit, Nucl. Instrum. Meth. A 506 (2003) 250 [INSPIRE]. JHEP06(2018)102 JHEP06(2018)102 [35] CMS collaboration, Particle-flow reconstruction and global event description with the CMS
detector, 2017 JINST 12 P10003 [arXiv:1706.04965] [INSPIRE]. [36] M. Cacciari, G.P. Salam and G. Soyez, The anti-kt jet clustering algorithm, JHEP 04 (2008)
063 [arXiv:0802.1189] [INSPIRE]. [37] M. Cacciari, G.P. Salam and G. Soyez, FastJet user manual, Eur. Phys. J. C 72 (2012) 1896
[arXiv:1111.6097] [INSPIRE]. [38] CMS collaboration, Determination of jet energy calibration and transverse momentum
resolution in CMS, 2011 JINST 6 P11002 [arXiv:1107.4277] [INSPIRE]. [39] CMS Collaboration, Identification of b quark jets at the CMS Experiment in the LHC Run 2,
CMS-PAS-BTV-15-001 (2015). [40] T. Hastie, R. Tibshirani and J. Friedman, The elements of statistical learning,
Springer-Verlag New York (2009). [41] A. Hocker et al., TMVA — Toolkit for Multivariate Data Analysis, PoS(ACAT)040
[physics/0703039] [INSPIRE]. [42] J. Butterworth et al., PDF4LHC recommendations for LHC Run II, J. Phys. G 43 (2016)
023001 [arXiv:1510.03865] [INSPIRE]. [43] A.D. Martin, W.J. Stirling, R.S. Thorne and G. Watt, Uncertainties on αs in global PDF
analyses and implications for predicted hadronic cross sections, Eur. Phys. J. References C 64 (2009)
653 [arXiv:0905.3531] [INSPIRE]. [44] J. Gao et al., CT10 next-to-next-to-leading order global analysis of QCD, Phys. Rev. D 89
(2014) 033009 [arXiv:1302.6246] [INSPIRE]. [45] J.R. Christiansen and P.Z. Skands, String formation beyond leading colour, JHEP 08 (2015)
003 [arXiv:1505.01681] [INSPIRE]. [46] S. Argyropoulos and T. Sj¨ostrand, Effects of color reconnection on t¯t final states at the LHC,
JHEP 11 (2014) 043 [arXiv:1407.6653] [INSPIRE]. [47] CMS collaboration, Jet energy scale and resolution in the CMS experiment in pp collisions
at 8 TeV, 2017 JINST 12 P02014 [arXiv:1607.03663] [INSPIRE]. [48] CMS collaboration, Measurement of differential cross sections for top quark pair production
using the lepton+jets final state in proton-proton collisions at 13 TeV, Phys. Rev. D 95
(2017) 092001 [arXiv:1610.04191] [INSPIRE]. – 16 – [49] A. Bredenstein, A. Denner, S. Dittmaier and S. Pozzorini, NLO QCD corrections to
pp →t¯tb¯b + X at the LHC, Phys. Rev. Lett. 103 (2009) 012002 [arXiv:0905.0110] [INSPIRE]. [50] CMS collaboration, Measurements of t¯t cross sections in association with b jets and inclusive
jets and their ratio using dilepton final states in pp collisions at √s = 13 TeV, Phys. Lett. B
776 (2018) 355 [arXiv:1705.10141] [INSPIRE]. [51] A.L. Read, Presentation of search results: the CL(s) technique, J. Phys. G 28 (2002) 2693
[INSPIRE]. [52] T. Junk, Confidence level computation for combining searches with small statistics, Nucl. Instrum. Meth. A 434 (1999) 435 [hep-ex/9902006] [INSPIRE]. [53] G. Cowan, K. Cranmer, E. Gross and O. Vitells, Asymptotic formulae for likelihood-based
tests of new physics, Eur. Phys. J. C 71 (2011) 1554 [Erratum ibid. C 73 (2013) 2501]
[arXiv:1007.1727] [INSPIRE]. [54] J. Gao, C.S. Li and H.X. Zhu, Top quark decay at next-to-next-to leading order in QCD,
Phys. Rev. Lett. 110 (2013) 042001 [arXiv:1210.2808] [INSPIRE]. [49] A. Bredenstein, A. Denner, S. Dittmaier and S. Pozzorini, NLO QCD corrections to
pp →t¯tb¯b + X at the LHC, Phys. Rev. Lett. 103 (2009) 012002 [arXiv:0905.0110] [INSPIRE]. [50] CMS collaboration, Measurements of t¯t cross sections in association with b jets and inclusive
jets and their ratio using dilepton final states in pp collisions at √s = 13 TeV, Phys. Lett. B
776 (2018) 355 [arXiv:1705.10141] [INSPIRE]. [51] A.L. Read, Presentation of search results: the CL(s) technique, J. Phys. G 28 (2002) 2693
[INSPIRE]. [52] T. Junk, Confidence level computation for combining searches with small statistics, Nucl. Instrum. Meth. A 434 (1999) 435 [hep-ex/9902006] [INSPIRE]. JHEP06(2018)102 [53] G. Cowan, K. References Cranmer, E. Gross and O. Vitells, Asymptotic formulae for likelihood-based
tests of new physics, Eur. Phys. J. C 71 (2011) 1554 [Erratum ibid. C 73 (2013) 2501]
[arXiv:1007.1727] [INSPIRE]. [54] J. Gao, C.S. Li and H.X. Zhu, Top quark decay at next-to-next-to leading order in QCD,
Phys. Rev. Lett. 110 (2013) 042001 [arXiv:1210.2808] [INSPIRE]. – 17 – The CMS collaboration The CMS collaboration Yerevan Physics Institute, Yerevan, Armenia
A.M. Sirunyan, A. Tumasyan Vrije Universiteit Brussel, Brussel, Belgium j
,
,
g
S. Abu Zeid, F. Blekman, J. D’Hondt, I. De Bruyn, J. De Clercq, K. Deroover, G. Flouris,
D. Lontkovskyi, S. Lowette, I. Marchesini, S. Moortgat, L. Moreels, Q. Python, K. Skovpen,
S. Tavernier, W. Van Doninck, P. Van Mulders, I. Van Parijs S. Tavernier, W. Van Doninck, P. Van Mulders, I. Van Parijs Universit´e Libre de Bruxelles, Bruxelles, Belgium Universit´e Libre de Bruxelles, Bruxelles, Belgium D. Beghin, B. Bilin, H. Brun, B. Clerbaux, G. De Lentdecker, H. Delannoy, B. Dorney,
G. Fasanella, L. Favart, R. Goldouzian, A. Grebenyuk, A.K. Kalsi, T. Lenzi, J. Luetic,
T. Maerschalk, A. Marinov, T. Seva, E. Starling, C. Vander Velde, P. Vanlaer, D. Van-
nerom, R. Yonamine, F. Zenoni T. Maerschalk, A. Marinov, T. Seva, E. Starling, C. Vander Velde, P. Vanlaer, D. Van-
nerom, R. Yonamine, F. Zenoni Ghent University, Ghent, Belgium Yerevan Physics Institute, Yerevan, Armenia
A.M. Sirunyan, A. Tumasyan Yerevan Physics Institute, Yerevan, Armenia
A.M. Sirunyan, A. Tumasyan Institut f¨ur Hochenergiephysik, Wien, Austria
W. Adam, F. Ambrogi, E. Asilar, T. Bergauer, J. Brandstetter, E. Brondolin, M. Drag-
icevic, J. Er¨o, A. Escalante Del Valle, M. Flechl, M. Friedl, R. Fr¨uhwirth1, V.M. Ghete,
J. Grossmann, J. Hrubec, M. Jeitler1, A. K¨onig, N. Krammer, I. Kr¨atschmer, D. Liko,
T. Madlener, I. Mikulec, E. Pree, N. Rad, H. Rohringer, J. Schieck1, R. Sch¨ofbeck,
M. Spanring, D. Spitzbart, A. Taurok, W. Waltenberger, J. Wittmann, C.-E. Wulz1,
M. Zarucki Institut f¨ur Hochenergiephysik, Wien, Austria
W. Adam, F. Ambrogi, E. Asilar, T. Bergauer, J. Brandstetter, E. Brondolin, M. Drag-
icevic, J. Er¨o, A. Escalante Del Valle, M. Flechl, M. Friedl, R. Fr¨uhwirth1, V.M. Ghete,
J. Grossmann, J. Hrubec, M. Jeitler1, A. K¨onig, N. Krammer, I. Kr¨atschmer, D. Liko,
T. Madlener, I. Mikulec, E. Pree, N. Rad, H. Rohringer, J. Schieck1, R. Sch¨ofbeck,
M. Spanring, D. Spitzbart, A. Taurok, W. Waltenberger, J. Wittmann, C.-E. Wulz1,
M. Zarucki JHEP06(2018)102 Institute for Nuclear Problems, Minsk, Belarus
V. Chekhovsky, V. Mossolov, J. Suarez Gonzalez Universiteit Antwerpen, Antwerpen, Belgium
E.A. De Wolf, D. Di Croce, X. Janssen, J. Lauwers, M. Van De Klundert, H. Van
Haevermaet, P. Van Mechelen, N. Van Remortel E.A. De Wolf, D. Di Croce, X. Janssen, J. Lauwers, M. Van De Klundert, H. Van
Haevermaet, P. Van Mechelen, N. Van Remortel Vrije Universiteit Brussel, Brussel, Belgium Ghent University, Ghent, Belgium T. Cornelis, D. Dobur, A. Fagot, M. Gul, I. Khvastunov2, D. Poyraz, C. Roskas, S. Salva,
D. Trocino, M. Tytgat, W. Verbeke, M. Vit, N. Zaganidis Universit´e Catholique de Louvain, Louvain-la-Neuve, Belgium
H. Bakhshiansohi, O. Bondu, S. Brochet, G. Bruno, C. Caputo, A. Caudron, P. David, S. De
Visscher, C. Delaere, M. Delcourt, B. Francois, A. Giammanco, M. Komm, G. Krintiras,
V. Lemaitre, A. Magitteri, A. Mertens, M. Musich, K. Piotrzkowski, L. Quertenmont,
A. Saggio, M. Vidal Marono, S. Wertz, J. Zobec Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, Brazil
W.L. Ald´a J´unior, F.L. Alves, G.A. Alves, L. Brito, G. Correia Silva, C. Hensel, A. Moraes,
M.E. Pol, P. Rebello Teles Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
E. Belchior Batista Das Chagas, W. Carvalho, J. Chinellato3, E. Coelho, E.M. Da
Costa, G.G. Da Silveira4, D. De Jesus Damiao, S. Fonseca De Souza, L.M. Huertas – 18 – Guativa, H. Malbouisson, M. Melo De Almeida, C. Mora Herrera, L. Mundim, H. Nogima,
L.J. Sanchez Rosas, A. Santoro, A. Sznajder, M. Thiel, E.J. Tonelli Manganote3, F. Torres
Da Silva De Araujo, A. Vilela Pereira Universidade Estadual Paulistaa, Universidade Federal do ABCb, S˜ao Paulo,
Brazil S. Ahujaa,
C.A. Bernardesa,
T.R. Fernandez
Perez
Tomeia,
E.M. Gregoresb,
P.G. Mercadanteb, S.F. Novaesa, Sandra S. Padulaa, D. Romero Abadb, J.C. Ruiz Vargasa Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of
Sciences, Sofia, Bulgaria JHEP06(2018)102 A. Aleksandrov, R. Hadjiiska, P. Iaydjiev, M. Misheva, M. Rodozov, M. Shopova, G. Sul-
tanov University of Sofia, Sofia, Bulgaria
A. Dimitrov, L. Litov, B. Pavlov, P. Petkov University of Sofia, Sofia, Bulgaria University of Sofia, Sofia, Bulgaria A. Dimitrov, L. Litov, B. Pavlov, P. Petkov Beihang University, Beijing, China
W. Fang5, X. Gao5, L. Yuan Beihang University, Beijing, China
W. Fang5, X. Gao5, L. Yuan Institute of High Energy Physics, Beijing, China Institute of High Energy Physics, Beijing, China
M. Ahmad, J.G. Bian, G.M. Chen, H.S. Chen, M. Chen, Y. Chen, C.H. Jiang, D. Leggat,
H. Liao, Z. Liu, F. Romeo, S.M. Shaheen, A. Spiezia, J. Tao, C. Wang, Z. Wang, E. Yazgan,
H. Zhang, J. Zhao M. Ahmad, J.G. Bian, G.M. Chen, H.S. Chen, M. Chen, Y. Chen, C.H. Jiang, D. Legga H. Liao, Z. Liu, F. Romeo, S.M. Shaheen, A. Spiezia, J. Tao, C. Wang, Z. Wang, E. Yazga
H. Zhang, J. Zhao State Key Laboratory of Nuclear Physics and Technology, Peking University,
Beijing, China Universidad San Francisco de Quito, Quito, Ecuador
E. Carrera Jarrin Universidad San Francisco de Quito, Quito, Ecuador
E. Carrera Jarrin Academy of Scientific Research and Technology of the Arab Republic of Egypt,
Egyptian Network of High Energy Physics, Cairo, Egypt
A.A. Abdelalim8,9, Y. Mohammed10, E. Salama11,12 National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
S. Bhowmik, R.K. Dewanjee, M. Kadastik, L. Perrini, M. Raidal, C. Veelken JHEP06(2018)102 Department of Physics, University of Helsinki, Helsinki, Finland
P. Eerola, H. Kirschenmann, J. Pekkanen, M. Voutilainen State Key Laboratory of Nuclear Physics and Technology, Peking Universit
Beijing, China Y. Ban, G. Chen, J. Li, Q. Li, S. Liu, Y. Mao, S.J. Qian, D. Wang, Z. Xu, F. Zhang5 Tsinghua University, Beijing, China
Y. Wang Tsinghua University, Beijing, China
Y. Wang Universidad de Los Andes, Bogota, Colombia Universidad de Los Andes, Bogota, Colombia
C. Avila,
A. Cabrera,
C.A. Carrillo Montoya,
L.F. Chaparro Sierra,
C. Florez,
C.F. Gonz´alez Hern´andez, J.D. Ruiz Alvarez, M.A. Segura Delgado C. Avila,
A. Cabrera,
C.A. Carrillo Montoya,
L.F. Chaparro Sierra,
C. Flore
C.F. Gonz´alez Hern´andez, J.D. Ruiz Alvarez, M.A. Segura Delgado University of Split, Faculty of Electrical Engineering, Mechanical Engineering
and Naval Architecture, Split, Croatia
B. Courbon, N. Godinovic, D. Lelas, I. Puljak, P.M. Ribeiro Cipriano, T. Sculac University of Split, Faculty of Science, Split, Croatia
Z. Antunovic, M. Kovac Institute Rudjer Boskovic, Zagreb, Croatia
V. Brigljevic, D. Ferencek, K. Kadija, B. Mesic, A. Starodumov6, T. Susa V. Brigljevic, D. Ferencek, K. Kadija, B. Mesic, A. Starodumov6, T. Susa University of Cyprus, Nicosia, Cyprus
M.W. Ather, A. Attikis, G. Mavromanolakis, J. Mousa, C. Nicolaou, F. Ptochos,
P.A. Razis, H. Rykaczewski – 19 – Charles University, Prague, Czech Republic
M. Finger7, M. Finger Jr.7 Helsinki Institute of Physics, Helsinki, Finland Tsamalaidze7 RWTH Aachen University, I. Physikalisches Institut, Aachen, Germany RWTH Aachen University, I. Physikalisches Institut, Aachen, Germany
C. Autermann, L. Feld, M.K. Kiesel, K. Klein, M. Lipinski, M. Preuten, C. Schomak
15 RWTH Aachen University, I. Physikalisches Institut, Aachen, Germany
C. Autermann, L. Feld, M.K. Kiesel, K. Klein, M. Lipinski, M. Preuten, C. Schomakers,
J. Schulz, M. Teroerde, B. Wittmer, V. Zhukov15 C. Autermann, L. Feld, M.K. Kiesel, K. Klein, M. Lipinski, M. Preuten, C. Schomakers,
J. Schulz, M. Teroerde, B. Wittmer, V. Zhukov15 RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany
A. Albert, D. Duchardt, M. Endres, M. Erdmann, S. Erdweg, T. Esch, R. Fischer, A. G¨uth, RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany
A. Albert, D. Duchardt, M. Endres, M. Erdmann, S. Erdweg, T. Esch, R. Fischer, A. G¨uth,
T. Hebbeker, C. Heidemann, K. Hoepfner, S. Knutzen, M. Merschmeyer, A. Meyer,
P. Millet, S. Mukherjee, T. Pook, M. Radziej, H. Reithler, M. Rieger, F. Scheuch,
D. Teyssier, S. Th¨uer A. Albert, D. Duchardt, M. Endres, M. Erdmann, S. Erdweg, T. Esch, R. Fischer, A. G¨uth,
T. Hebbeker, C. Heidemann, K. Hoepfner, S. Knutzen, M. Merschmeyer, A. Meyer,
P Mill t
S
M kh
j
T
P
k
M
R d i j
H
R ithl
M
Ri
F
S h
h A. Albert, D. Duchardt, M. Endres, M. Erdmann, S. Erdweg, T. Esch, R. Fischer, A. Guth,
T. Hebbeker, C. Heidemann, K. Hoepfner, S. Knutzen, M. Merschmeyer, A. Meyer, P. Millet, S. Mukherjee, T. Pook, M. Radziej, H. Reithler, M. Rieger, F. Scheuch,
D. Teyssier, S. Th¨uer RWTH Aachen University, III. Physikalisches Institut B, Aachen, Germany
G. Fl¨ugge, B. Kargoll, T. Kress, A. K¨unsken, T. M¨uller, A. Nehrkorn, A. Nowack,
C. Pistone, O. Pooth, A. Stahl17 Deutsches Elektronen-Synchrotron, Hamburg, Germany
M. Aldaya Martin,
T. Arndt,
C. Asawatangtrakuldee,
K. Beernaert,
O. Behnke,
U. Behrens, A. Berm´udez Mart´ınez, A.A. Bin Anuar, K. Borras18, V. Botta, A. Campbell,
P. Connor, C. Contreras-Campana, F. Costanza, C. Diez Pardos, G. Eckerlin, D. Eckstein,
T. Eichhorn, E. Eren, E. Gallo19, J. Garay Garcia, A. Geiser, J.M. Grados Luyando,
A. Grohsjean, P. Gunnellini, M. Guthoff, A. Harb, J. Hauk, M. Hempel20, H. Jung,
M. Kasemann, J. Keaveney, C. Kleinwort, I. Korol, D. Kr¨ucker, W. Lange, A. Lelek,
T. Lenz, K. Lipka, W. Lohmann20, R. Mankel, I.-A. Melzer-Pellmann, A.B. Meyer,
M. Missiroli, G. Helsinki Institute of Physics, Helsinki, Finland Mittag, J. Mnich, A. Mussgiller, E. Ntomari, D. Pitzl, A. Raspereza,
M. Savitskyi, P. Saxena, R. Shevchenko, N. Stefaniuk, G.P. Van Onsem, R. Walsh, Y. Wen,
K. Wichmann, C. Wissing, O. Zenaiev Helsinki Institute of Physics, Helsinki, Finland Helsinki Institute of Physics, Helsinki, Finland J. Havukainen, J.K. Heikkil¨a, T. J¨arvinen, V. Karim¨aki, R. Kinnunen, T. Lamp´en, J. Havukainen, J.K. Heikkil¨a, T. J¨arvinen, V. Karim¨aki, R. Kinnunen, T. Lamp´en,
K. Lassila-Perini, S. Laurila, S. Lehti, T. Lind´en, P. Luukka, T. M¨aenp¨a¨a, H. Siikonen, J. Havukainen, J.K. Heikkil¨a, T. J¨arvinen, V. Karim¨aki, R. Kinnunen, T. Lamp´en,
K. Lassila-Perini, S. Laurila, S. Lehti, T. Lind´en, P. Luukka, T. M¨aenp¨a¨a, H. Siikonen,
E. Tuominen, J. Tuominiemi Lappeenranta University of Technology, Lappeenranta, Finland
T. Tuuva IRFU, CEA, Universit´e Paris-Saclay, Gif-sur-Yvette, France ,
,
y,
,
M. Besancon, F. Couderc, M. Dejardin, D. Denegri, J.L. Faure, F. Ferri, S. Ganjour,
S. Ghosh, A. Givernaud, P. Gras, G. Hamel de Monchenault, P. Jarry, C. Leloup, E. Locci,
M. Machet, J. Malcles, G. Negro, J. Rander, A. Rosowsky, M. ¨O. Sahin, M. Titov Laboratoire Leprince-Ringuet, Ecole polytechnique, CNRS/IN2P3, Univer-
sit´e Paris-Saclay, Palaiseau, France A. Abdulsalam13, C. Amendola, I. Antropov, S. Baffioni, F. Beaudette, P. Busson,
L. Cadamuro, C. Charlot, R. Granier de Cassagnac, M. Jo, I. Kucher, S. Lisniak,
A. Lobanov, J. Martin Blanco, M. Nguyen, C. Ochando, G. Ortona, P. Paganini, P. Pigard,
R. Salerno, J.B. Sauvan, Y. Sirois, A.G. Stahl Leiton, T. Strebler, Y. Yilmaz, A. Zabi,
A. Zghiche R. Salerno, J.B. Sauvan, Y. Sirois, A.G. Stahl Leiton, T. Strebler, Y. Yilmaz, A. Zab
A. Zghiche A. Zghiche Universit´e de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg,
France J.-L. Agram14, J. Andrea, D. Bloch, J.-M. Brom, M. Buttignol, E.C. Chabert, C. Collard,
E. Conte14, X. Coubez, F. Drouhin14, J.-C. Fontaine14, D. Gel´e, U. Goerlach, M. Jansov´a,
P. Juillot, A.-C. Le Bihan, N. Tonon, P. Van Hove Centre de Calcul de l’Institut National de Physique Nucleaire et de Physique
des Particules, CNRS/IN2P3, Villeurbanne, France
S. Gadrat – 20 – Universit´e de Lyon, Universit´e Claude Bernard Lyon 1, CNRS-IN2P3, Institut
de Physique Nucl´eaire de Lyon, Villeurbanne, France S. Beauceron, C. Bernet, G. Boudoul, N. Chanon, R. Chierici, D. Contardo, P. Depass S. Beauceron, C. Bernet, G. Boudoul, N. Chanon, R. Chierici, D. Contardo, P. Depasse,
H. El Mamouni, J. Fay, L. Finco, S. Gascon, M. Gouzevitch, G. Grenier, B. Ille, F. Lagarde,
I.B. Laktineh, M. Lethuillier, L. Mirabito, A.L. Pequegnot, S. Perries, A. Popov15,
V. Sordini, M. Vander Donckt, S. Viret, S. Zhang Georgian Technical University, Tbilisi, Georgia
T. Toriashvili16 Tbilisi State University, Tbilisi, Georgia Tbilisi State University, Tbilisi, Georgia
Z. Tsamalaidze7 JHEP06(2018)102 Z. University of Hamburg, Hamburg, Germany R. Aggleton, S. Bein, V. Blobel, M. Centis Vignali, T. Dreyer, E. Garutti, D. Gonzalez,
J. Haller, A. Hinzmann, M. Hoffmann, A. Karavdina, R. Klanner, R. Kogler, N. Kovalchuk,
S. Kurz, D. Marconi, M. Meyer, M. Niedziela, D. Nowatschin, F. Pantaleo17, T. Peiffer,
A. Perieanu, C. Scharf, P. Schleper, A. Schmidt, S. Schumann, J. Schwandt, J. Sonneveld,
H. Stadie, G. Steinbr¨uck, F.M. Stober, M. St¨over, H. Tholen, D. Troendle, E. Usai,
A. Vanhoefer, B. Vormwald – 21 – Institut f¨ur Experimentelle Kernphysik, Karlsruhe, Germany
M. Akbiyik, C. Barth, M. Baselga, S. Baur, E. Butz, R. Caspart, T. Chwalek, F. Colombo,
W. De Boer, A. Dierlamm, N. Faltermann, B. Freund, R. Friese, M. Giffels, M.A. Har-
rendorf, F. Hartmann17, S.M. Heindl, U. Husemann, F. Kassel17, S. Kudella, H. Mildner,
M.U. Mozer, Th. M¨uller, M. Plagge, G. Quast, K. Rabbertz, M. Schr¨oder, I. Shvetsov,
G. Sieber, H.J. Simonis, R. Ulrich, S. Wayand, M. Weber, T. Weiler, S. Williamson,
C. W¨ohrmann, R. Wolf Institut f¨ur Experimentelle Kernphysik, Karlsruhe, Germany Institute of Nuclear and Particle Physics (INPP),
NCSR Demokritos, Aghia
Paraskevi, Greece JHEP06(2018)102 JHEP06(2018)102 G. Anagnostou, G. Daskalakis, T. Geralis, A. Kyriakis, D. Loukas, I. Topsis-Giotis National and Kapodistrian University of Athens, Athens, Greece
G. Karathanasis, S. Kesisoglou, A. Panagiotou, N. Saoulidou, E. Tziaferi National Technical University of Athens, Athens, Greece
K. Kousouris University of Io´annina, Io´annina, Greece University of Io´annina, Io´annina, Greece University of Ioannina, Ioannina, Greece
I. Evangelou, C. Foudas, P. Gianneios, P. Katsoulis, P. Kokkas, S. Mallios, N. Manthos,
I. Papadopoulos, E. Paradas, J. Strologas, F.A. Triantis, D. Tsitsonis MTA-ELTE Lend¨ulet CMS Particle and Nuclear Physics Group, E¨otv¨os Lor´and
University, Budapest, Hungary
M. Csanad, N. Filipovic, G. Pasztor, O. Sur´anyi, G.I. Veres21 Wigner Research Centre for Physics, Budapest, Hungary
G. Bencze, C. Hajdu, D. Horvath22, ´A. Hunyadi, F. Sikler, V. Veszpremi, G. Vesztergombi21 Institute of Nuclear Research ATOMKI, Debrecen, Hungary
N. Beni, S. Czellar, J. Karancsi23, A. Makovec, J. Molnar, Z. Szillasi Institute of Physics, University of Debrecen, Debrecen, Hungary
M. Bart´ok21, P. Raics, Z.L. Trocsanyi, B. Ujvari Indian Institute of Science (IISc), Bangalore, India
S. Choudhury, J.R. Komaragiri Indian Institute of Science (IISc), Bangalore, India
S. Choudhury, J.R. Komaragiri National Institute of Science Education and Research, Bhubaneswar, India
S. Bahinipati24, P. Mal, K. Mandal, A. Nayak25, D.K. Sahoo24, N. Sahoo, S.K. Swain
Panjab University Chandigarh India S. Bansal, S.B. Beri, V. Bhatnagar, R. Chawla, N. Dhingra, A. Kaur, M. University of Hamburg, Hamburg, Germany Kaur, S. Kaur,
R. Kumar, P. Kumari, A. Mehta, J.B. Singh, G. Walia R. Kumar, P. Kumari, A. Mehta, J.B. Singh, G. Walia University of Delhi, Delhi, India University of Delhi, Delhi, India
Ashok Kumar, Aashaq Shah, A. Bhardwaj, S. Chauhan, B.C. Choudhary, R.B. Garg,
S. Keshri, A. Kumar, S. Malhotra, M. Naimuddin, K. Ranjan, R. Sharma – 22 – Saha Institute of Nuclear Physics, HBNI, Kolkata, India
R. Bhardwaj26, R. Bhattacharya, S. Bhattacharya, U. Bhawandeep26, D. Bhowmik, S. Dey,
S. Dutt26, S. Dutta, S. Ghosh, N. Majumdar, A. Modak, K. Mondal, S. Mukhopadhyay,
S. Nandan, A. Purohit, P.K. Rout, A. Roy, S. Roy Chowdhury, S. Sarkar, M. Sharan,
B. Singh, S. Thakur26 Saha Institute of Nuclear Physics, HBNI, Kolkata, India Indian Institute of Technology Madras, Madras, India
P.K. Behera Bhabha Atomic Research Centre, Mumbai, India Bhabha Atomic Research Centre, Mumbai, India R. Chudasama, D. Dutta, V. Jha, V. Kumar, A.K. Mohanty17, P.K. Netrakanti, L.M. Pant,
P. Shukla, A. Topkar JHEP06(2018)102 Tata Institute of Fundamental Research-A, Mumbai, India Tata Institute of Fundamental Research-A, Mumbai, India
T. Aziz, S. Dugad, B. Mahakud, S. Mitra, G.B. Mohanty, N. Sur, B. Sutar T. Aziz, S. Dugad, B. Mahakud, S. Mitra, G.B. Mohanty, N. Sur, B. Sutar Tata Institute of Fundamental Research-B, Mumbai, India
S. Banerjee, S. Bhattacharya, S. Chatterjee, P. Das, M. Guchait, Sa. Jain, S. Kumar,
M. Maity27, G. Majumder, K. Mazumdar, T. Sarkar27, N. Wickramage28 Indian Institute of Science Education and Research (IISER), Pune, India
S. Chauhan, S. Dube, V. Hegde, A. Kapoor, K. Kothekar, S. Pandey, A. Rane, S. Sharma Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
S. Chenarani29, E. Eskandari Tadavani, S.M. Etesami29, M. Khakzad, M. Mohammadi
Najafabadi, M. Naseri, S. Paktinat Mehdiabadi30, F. Rezaei Hosseinabadi, B. Safarzadeh31,
M. Zeinali Najafabadi, M. Naseri, S. Paktinat Mehdiabadi30, F. Rezaei Hosseinabadi, B. Safarzadeh3
M. Zeinali University College Dublin, Dublin, Ireland
M. Felcini, M. Grunewald INFN Sezione di Paviaa, Universit`a di Paviab, Pavia, Italy ,
,
,
y
A. Braghieria, A. Magnania, P. Montagnaa,b, S.P. Rattia,b, V. Rea, M. Ressegottia,b,
C. Riccardia,b, P. Salvinia, I. Vaia,b, P. Vituloa,b INFN Sezione di Perugiaa, Universit`a di Perugiab, Perugia, Italy INFN Sezione di Perugiaa, Universit`a di Perugiab, Perugia, Italy
L. Alunni Solestizia,b, M. Biasinia,b, G.M. Bileia, C. Cecchia,b, D. Ciangottinia,b, L. Fan`oa,b,
P. Laricciaa,b, R. Leonardia,b, E. Manonia, G. Mantovania,b, V. Mariania,b, M. Menichellia,
A. Rossia,b, A. Santocchiaa,b, D. Spigaa INFN Sezione di Pisaa, Universit`a di Pisab, Scuola Normale Superiore di Pisac,
Pisa, Italy University College Dublin, Dublin, Ireland
M. Felcini, M. Grunewald INFN Sezione di Baria, Universit`a di Barib, Politecnico di Baric, Bari, Italy
M. Abbresciaa,b, C. Calabriaa,b, A. Colaleoa, D. Creanzaa,c, L. Cristellaa,b, N. De Filippisa,c,
M. De Palmaa,b, F. Erricoa,b, L. Fiorea, G. Iasellia,c, S. Lezkia,b, G. Maggia,c, M. Maggia,
B. Marangellia,b, G. Minielloa,b, S. Mya,b, S. Nuzzoa,b, A. Pompilia,b, G. Pugliesea,c,
R. Radognaa, A. Ranieria, G. Selvaggia,b, A. Sharmaa, L. Silvestrisa,17, R. Vendittia,
P. Verwilligena, G. Zitoa P. Verwilligena, G. Zitoa INFN Sezione di Bolognaa, Universit`a di Bolognab, Bologna, Italy
G. Abbiendia, C. Battilanaa,b, D. Bonacorsia,b, L. Borgonovia,b, S. Braibant-Giacomellia,b,
R. Campaninia,b,
P. Capiluppia,b,
A. Castroa,b,
F.R. Cavalloa,
S.S. Chhibraa,b,
G. Codispotia,b, M. Cuffiania,b, G.M. Dallavallea, F. Fabbria, A. Fanfania,b, D. Fasanellaa,b,
P. Giacomellia, C. Grandia, L. Guiduccia,b, F. Iemmi, S. Marcellinia, G. Masettia,
A. Montanaria, F.L. Navarriaa,b, A. Perrottaa, A.M. Rossia,b, T. Rovellia,b, G.P. Sirolia,b,
N. Tosia INFN Sezione di Cataniaa, Universit`a di Cataniab, Catania, Italy
S. Albergoa,b, S. Costaa,b, A. Di Mattiaa, F. Giordanoa,b, R. Potenzaa,b, A. Tricomia,b,
C. Tuvea,b – 23 – INFN Sezione di Firenzea, Universit`a di Firenzeb, Firenze, Italy INFN Sezione di Firenzea, Universit`a di Firenzeb, Firenze, Italy
G. Barbaglia, K. Chatterjeea,b, V. Ciullia,b, C. Civininia, R. D’Alessandroa,b, E. Focardia,b,
P. Lenzia,b, M. Meschinia, S. Paolettia, L. Russoa,32, G. Sguazzonia, D. Stroma, L. Viliania Barbaglia, K. Chatterjeea,b, V. Ciullia,b, C. Civininia, R. D’Alessandroa,b, E. Focardia,b,
Lenzia,b, M. Meschinia, S. Paolettia, L. Russoa,32, G. Sguazzonia, D. Stroma, L. Viliania INFN Laboratori Nazionali di Frascati, Frascati, Italy
L. Benussi, S. Bianco, F. Fabbri, D. Piccolo, F. Primavera17 INFN Laboratori Nazionali di Frascati, Frascati, Italy
L Benussi S Bianco F Fabbri D Piccolo F Primavera17 INFN Sezione di Genovaa, Universit`a di Genovab, Genova, Italy
V. Calvellia,b, F. Ferroa, F. Raveraa,b, E. Robuttia, S. Tosia,b INFN Sezione di Milano-Bicoccaa, Universit`a di Milano-Bicoccab,
Milano,
Italy Italy A. Benagliaa, A. Beschib, L. Brianzaa,b, F. Brivioa,b, V. Cirioloa,b,17, M.E. Dinardoa,b,
S. Fiorendia,b, S. Gennaia, A. Ghezzia,b, P. Govonia,b, M. Malbertia,b, S. Malvezzia,
R A Manzonia,b D Menascea L Moronia M Paganonia,b K Pauwelsa,b D Pedrinia A. Benagliaa, A. Beschib, L. Brianzaa,b, F. Brivioa,b, V. Cirioloa,b,17, M.E. Dinardoa A. Benaglia , A. Beschi , L. Brianza
, F. Brivio
, V. Ciriolo
, M.E. Dinardo
,
S. Fiorendia,b, S. Gennaia, A. Ghezzia,b, P. Govonia,b, M. Malbertia,b, S. Malvezzia, R.A. Manzonia,b, D. Menascea, L. Moronia, M. Paganonia,b, K. Pauwelsa,b, D. Pedrinia,
S. Pigazzinia,b,33, S. Ragazzia,b, T. Tabarelli de Fatisa,b INFN Sezione di Napolia, Universit`a di Napoli ’Federico II’b, Napoli, Italy,
Universit`a della Basilicatac, Potenza, Italy, Universit`a G. Marconid, Roma,
Italy S. Buontempoa, N. Cavalloa,c, S. Di Guidaa,d,17, F. Fabozzia,c, F. Fiengaa,b, A.O.M. Iorioa
d 17
17
b S. Buontempoa, N. Cavalloa,c, S. Di Guidaa,d,17, F. Fabozzia,c, F. Fiengaa,b, A.O.M. Iorioa,b,
W.A. Khana, L. Listaa, S. Meolaa,d,17, P. Paoluccia,17, C. Sciaccaa,b, F. Thyssena S. Buontempo , N. Cavallo
, S. Di Guida
, F. Fabozzi
, F. Fienga
, A.O.M. Iorio
,
W.A. Khana, L. Listaa, S. Meolaa,d,17, P. Paoluccia,17, C. Sciaccaa,b, F. Thyssena INFN Sezione di Padovaa, Universit`a di Padovab, Padova, Italy, Universit`a di
Trentoc, Trento, Italy P. Azzia, N. Bacchettaa, L. Benatoa,b, M. Benettonia, A. Bolettia,b, R. Carlina,b,
P. Checchiaa, M. Dall’Ossoa,b, P. De Castro Manzanoa, T. Dorigoa, U. Dossellia,
F. Gasparinia,b, U. Gasparinia,b, A. Gozzelinoa, S. Lacapraraa, P. Lujan, M. Margonia,b,
A.T. Meneguzzoa,b, N. Pozzobona,b, P. Ronchesea,b, R. Rossina,b, F. Simonettoa,b, A. Tiko,
E. Torassaa, M. Zanettia,b, P. Zottoa,b, G. Zumerlea,b INFN Sezione di Paviaa, Universit`a di Paviab, Pavia, Italy INFN Sezione di Milano-Bicoccaa, Universit`a di Milano-Bicoccab,
Milano,
Italy JHEP06(2018)102 Hanyang University, Seoul, Korea J.A. Brochero Cifuentes, J. Goh, T.J. Kim J.A. Brochero Cifuentes, J. Goh, T.J. Kim Pisa, Italy K. Androsova, P. Azzurria,17, G. Bagliesia, L. Bianchinia, T. Boccalia, L. Borrello,
R. Castaldia, M.A. Cioccia,b, R. Dell’Orsoa, G. Fedia, L. Gianninia,c, A. Giassia,
M.T. Grippoa,32, F. Ligabuea,c, T. Lomtadzea, E. Mancaa,c, G. Mandorlia,c, A. Messineoa,b,
F. Pallaa, A. Rizzia,b, P. Spagnoloa, R. Tenchinia, G. Tonellia,b, A. Venturia, P.G. Verdinia R. Castaldi , M.A. Ciocci , , R. Dell Orso , G. Fedi , L. Giannini , , A. Giassi ,
M.T. Grippoa,32, F. Ligabuea,c, T. Lomtadzea, E. Mancaa,c, G. Mandorlia,c, A. Messineoa,b,
F. Pallaa, A. Rizzia,b, P. Spagnoloa, R. Tenchinia, G. Tonellia,b, A. Venturia, P.G. Verdinia – 24 – INFN Sezione di Romaa, Sapienza Universit`a di Romab, Rome, Italy
L. Baronea,b,
F. Cavallaria,
M. Cipriania,b,
N. Dacia,
D. Del
Rea,b,
E. Di
Marcoa,b,
M. Diemoza,
S. Gellia,b,
E. Longoa,b,
F. Margarolia,b,
B. Marzocchia,b,
P. Meridiania, G. Organtinia,b, R. Paramattia,b, F. Preiatoa,b, S. Rahatloua,b, C. Rovellia,
F. Santanastasioa,b INFN Sezione di Torinoa, Universit`a di Torinob, Torino, Italy, Universit`a del
Piemonte Orientalec, Novara, Italy Seoul National University, Seoul, Korea J. Almond, J. Kim, J.S. Kim, H. Lee, K. Lee, K. Nam, S.B. Oh, B.C. Radburn-Smith,
S.h. Seo, U.K. Yang, H.D. Yoo, G.B. Yu Korea University, Seoul, Korea S. Cho, S. Choi, Y. Go, D. Gyun, S. Ha, B. Hong, Y. Jo, Y. Kim, K. Lee, K.S. Lee, S. Lee,
J. Lim, S.K. Park, Y. Roh INFN Sezione di Torinoa, Universit`a di Torinob, Torino, Italy, Universit`a del
Piemonte Orientalec, Novara, Italy N. Amapanea,b, R. Arcidiaconoa,c, S. Argiroa,b, M. Arneodoa,c, N. Bartosika, R. Bellana,b, JHEP06(2018)102 C. Biinoa, N. Cartigliaa, F. Cennaa,b, M. Costaa,b, R. Covarellia,b, A. Deganoa,b,
N. Demariaa, B. Kiania,b, C. Mariottia, S. Masellia, E. Migliorea,b, V. Monacoa,b,
E. Monteila,b, M. Montenoa, M.M. Obertinoa,b, L. Pachera,b, N. Pastronea, M. Pelliccionia,
G.L. Pinna Angionia,b, A. Romeroa,b, M. Ruspaa,c, R. Sacchia,b, K. Shchelinaa,b, V. Solaa,
A. Solanoa,b, A. Staianoa, P. Traczyka,b E. Monteil , , M. Monteno , M.M. Obertino , , L. Pacher , , N. Pastrone , M. Pelliccioni ,
G.L. Pinna Angionia,b, A. Romeroa,b, M. Ruspaa,c, R. Sacchia,b, K. Shchelinaa,b, V. Solaa,
A. Solanoa,b, A. Staianoa, P. Traczyka,b INFN Sezione di Triestea, Universit`a di Triesteb, Trieste, Italy S. Belfortea, M. Casarsaa, F. Cossuttia, G. Della Riccaa,b, A. Zanettia Kyungpook National University, Daegu, Korea D.H. Kim, G.N. Kim, M.S. Kim, J. Lee, S. Lee, S.W. Lee, C.S. Moon, Y.D. Oh, S. Sekmen,
D.C. Son, Y.C. Yang Chonnam National University, Institute for Universe and Elementary Particles,
Kwangju, Korea H. Kim, D.H. Moon, G. Oh Hanyang University, Seoul, Korea Hanyang University, Seoul, Korea
J.A. Brochero Cifuentes, J. Goh, T.J. Kim National Centre for Particle Physics,
Universiti Malaya,
Kuala Lumpur,
Malaysia National Centre for Particle Physics,
Universiti Malaya,
Kuala Lumpur,
Malaysia I. Ahmed, Z.A. Ibrahim, M.A.B. Md Ali34, F. Mohamad Idris35, W.A.T. Wan Abdullah,
M.N. Yusli, Z. Zolkapli Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico
Reyes-Almanza, R, Ramirez-Sanchez, G., Duran-Osuna, M. C., H. Castilla-Valdez, E. De
La Cruz-Burelo, I. Heredia-De La Cruz36, Rabadan-Trejo, R. I., R. Lopez-Fernandez,
J. Mejia Guisao, A. Sanchez-Hernandez Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico
Reyes-Almanza, R, Ramirez-Sanchez, G., Duran-Osuna, M. C., H. Castilla-Valdez, E. De
La Cruz-Burelo, I. Heredia-De La Cruz36, Rabadan-Trejo, R. I., R. Lopez-Fernandez,
J. Mejia Guisao, A. Sanchez-Hernandez Universidad Iberoamericana, Mexico City, Mexico
S. Carrillo Moreno, C. Oropeza Barrera, F. Vazquez Valencia Universidad Iberoamericana, Mexico City, Mexico
S. Carrillo Moreno, C. Oropeza Barrera, F. Vazquez Valencia JHEP06(2018)102 Benemerita Universidad Autonoma de Puebla, Puebla, Mexico
J. Eysermans, I. Pedraza, H.A. Salazar Ibarguen, C. Uribe Estrada Universidad Aut´onoma de San Luis Potos´ı, San Luis Potos´ı, Mexico
A. Morelos Pineda University of Auckland, Auckland, New Zealand
D. Krofcheck University of Canterbury, Christchurch, New Zealand
P.H. Butler National Centre for Physics, Quaid-I-Azam University, Islamabad, Pakistan National Centre for Physics, Quaid-I-Azam University, Islamabad, Pakistan
A. Ahmad, M. Ahmad, Q. Hassan, H.R. Hoorani, A. Saddique, M.A. Shah, M. Shoaib,
M. Waqas A. Ahmad, M. Ahmad, Q. Hassan, H.R. Hoorani, A. Saddique, M.A. Shah, M. Shoaib,
M. Waqas University of Seoul, Seoul, Korea H. Kim, J.H. Kim, J.S.H. Lee, I.C. Park H. Kim, J.H. Kim, J.S.H. Lee, I.C. Park Sungkyunkwan University, Suwon, Korea
Y. Choi, C. Hwang, J. Lee, I. Yu Vilnius University, Vilnius, Lithuania Vilnius University, Vilnius, Lithuania V. Dudenas, A. Juodagalvis, J. Vaitkus V. Dudenas, A. Juodagalvis, J. Vaitkus – 25 – National Centre for Nuclear Research, Swierk, Poland National Centre for Nuclear Research, Swierk, Poland National Centre for Nuclear Research, Swierk, Poland
H. Bialkowska, M. Bluj, B. Boimska, T. Frueboes, M. G´orski, M. Kazana, K. Nawrocki,
M. Szleper, P. Zalewski Institute of Experimental Physics, Faculty of Physics, University of Warsaw,
Warsaw, Poland K. Bunkowski, A. Byszuk37, K. Doroba, A. Kalinowski, M. Konecki, J. Krolikowski,
M. Misiura, M. Olszewski, A. Pyskir, M. Walczak Laborat´orio de Instrumenta¸c˜ao e F´ısica Experimental de Part´ıculas, Lisboa,
Portugal Portugal P. Bargassa, C. Beir˜ao Da Cruz E Silva, A. Di Francesco, P. Faccioli, B. Galinhas,
M. Gallinaro, J. Hollar, N. Leonardo, L. Lloret Iglesias, M.V. Nemallapudi, J. Seixas,
G. Strong, O. Toldaiev, D. Vadruccio, J. Varela Joint Institute for Nuclear Research, Dubna, Russia
S. Afanasiev, P. Bunin, M. Gavrilenko, I. Golutvin, I. Gorbunov, A. Kamenev, V. Kar-
javin, A. Lanev, A. Malakhov, V. Matveev38,39, P. Moisenz, V. Palichik, V. Perelygin,
S. Shmatov, S. Shulha, N. Skatchkov, V. Smirnov, N. Voytishin, A. Zarubin – 26 – Petersburg Nuclear Physics Institute, Gatchina (St. Petersburg), Russia Petersburg Nuclear Physics Institute, Gatchina (St. Petersburg), Russia
Y I
V Ki
40 E K
t
41 P L
h
k
V M
i
V O
hki
I S
i Y. Ivanov, V. Kim40, E. Kuznetsova41, P. Levchenko, V. Murzin, V. Oreshkin, I. Smirno anov, V. Kim40, E. Kuznetsova41, P. Levchenko, V. Murzin, V. Oreshkin, I. Smirnov,
os o
V S li
o
L U a o
S Va ilo
A Vo ob e Y. Ivanov, V. Kim40, E. Kuznetsova41, P. Levchenko, V. Murzin, V. Oreshkin, I. Smirnov,
D. Sosnov, V. Sulimov, L. Uvarov, S. Vavilov, A. Vorobyev Y. Ivanov, V. Kim
, E. Kuznetsova
, P. Levchenko, V. Murzin, V. Oreshkin, I. Smirnov,
D. Sosnov, V. Sulimov, L. Uvarov, S. Vavilov, A. Vorobyev D. Sosnov, V. Sulimov, L. Uvarov, S. Vavilov, A. Vorobyev Institute for Nuclear Research, Moscow, Russia
Yu. Andreev, A. Dermenev, S. Gninenko, N. Golubev, A. Karneyeu, M. Kirsanov,
N. Krasnikov, A. Pashenkov, D. Tlisov, A. Toropin Institute for Theoretical and Experimental Physics, Moscow, Russia Institute for Theoretical and Experimental Physics, Moscow, Russia
V. Epshteyn, V. Gavrilov, N. Lychkovskaya, V. Popov, I. Pozdnyakov, G. Safronov,
A. Spiridonov, A. Stepennov, V. Stolin, M. Toms, E. Vlasov, A. Zhokin JHEP06(2018)102 Moscow Institute of Physics and Technology, Moscow, Russia
T. Aushev, A. Bylinkin39 National Research Nuclear University ’Moscow Engineering Physics Insti-
tute’ (MEPhI), Moscow, Russia
R. Chistov42, M. Danilov42, P. Parygin, D. Philippov, S. Polikarpov, E. Tarkovskii P.N. Lebedev Physical Institute, Moscow, Russia P.N. Lebedev Physical Institute, Moscow, Russia
V. Andreev, M. Azarkin39, I. Dremin39, M. Kirakosyan39, S.V. Rusakov, A. Terkulov Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University,
Moscow, Russia Moscow, Russia A. Baskakov, A. Belyaev, E. Boos, V. Bunichev, M. Dubinin43, L. Dudko, V. Klyukhin,
O Kodolova N Korneeva I Lokhtin I Miagkov S Obraztsov M Perfilov V Savrin Baskakov, A. Belyaev, E. Boos, V. Bunichev, M. Dubinin43, L. Dudko, V. Klyukhin, A. Baskakov, A. Belyaev, E. Boos, V. Bunichev, M. Dubinin43, L. Dudko, V. Klyukhin,
O. Kodolova, N. Korneeva, I. Lokhtin, I. Miagkov, S. Obraztsov, M. Perfilov, V. Savrin,
P. Volkov O. Kodolova, N. Korneeva, I. Lokhtin, I. Miagkov, S. Obraztsov, M. Perfilov, V. Savrin,
P. Volkov Novosibirsk State University (NSU), Novosibirsk, Russia
V. Blinov44, D. Shtol44, Y. Skovpen44 State Research Center of Russian Federation, Institute for High Energy Physics State Research Center of Russian Federation, Institute for High Energy Physics
of NRC "Kurchatov Institute", Protvino, Russia
I. Azhgirey, I. Bayshev, S. Bitioukov, D. Elumakhov, A. Godizov, V. Kachanov, A. Kalinin,
D. Konstantinov, P. Mandrik, V. Petrov, R. Ryutin, A. Sobol, S. Troshin, N. Tyurin,
A. Uzunian, A. Volkov I. Azhgirey, I. Bayshev, S. Bitioukov, D. Elumakhov, A. Godizov, V. Kachanov, A. Kalinin,
D. Konstantinov, P. Mandrik, V. Petrov, R. Ryutin, A. Sobol, S. Troshin, N. Tyurin,
A. Uzunian, A. Volkov National Research Tomsk Polytechnic University, Tomsk, Russia
A. Babaev University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear
Sciences, Belgrade, Serbia P. Adzic45, P. Cirkovic, D. Devetak, M. Dordevic, J. Milosevic Centro
de
Investigaciones
Energ´eticas
Medioambientales
y
Tec-
nol´ogicas (CIEMAT), Madrid, Spain J. Alcaraz Maestre, I. Bachiller, M. Barrio Luna, M. Cerrada, N. Colino, B. De La
Cruz, A. Delgado Peris, C. Fernandez Bedoya, J.P. Fern´andez Ramos, J. Flix, M.C. Fouz,
O. Gonzalez Lopez, S. Goy Lopez, J.M. Hernandez, M.I. Josa, D. Moran, A. P´erez-Calero Cruz, A. Delgado Peris, C. Fernandez Bedoya, J.P. Fern´andez Ramos, J. Flix, M.C. Fouz,
O. Gonzalez Lopez, S. Goy Lopez, J.M. Hernandez, M.I. Josa, D. Moran, A. P´erez-Calero Cruz, A. Delgado Peris, C. Fernandez Bedoya, J.P. Fernandez Ramos, J. Flix, M.C. Fouz,
O. Gonzalez Lopez, S. Goy Lopez, J.M. Hernandez, M.I. Josa, D. Moran, A. P´erez-Calero – 27 – Yzquierdo, J. Puerta Pelayo, I. Redondo, L. Romero, M.S. Soares, A. Triossi, A. ´Alvarez
Fern´andez Yzquierdo, J. Puerta Pelayo, I. Redondo, L. Romero, M.S. Soares, A. Triossi, A. ´Alvarez
Fern´andez Yzquierdo, J. Puerta Pelayo, I. Redondo, L. Romero, M.S. Soares, A. Triossi, A. ´Alvarez
Fern´andez Universidad Aut´onoma de Madrid, Madrid, Spain
C. Albajar, J.F. de Troc´oniz Universidad de Oviedo, Oviedo, Spain J. Moscow, Russia Cuevas, C. Erice, J. Fernandez Menendez, I. Gonzalez Caballero, J.R. Gonz´alez
Fern´andez, E. Palencia Cortezon, S. Sanchez Cruz, P. Vischia, J.M. Vizan Garcia Instituto de F´ısica de Cantabria (IFCA),
CSIC-Universidad de Cantabria,
Santander, Spain JHEP06(2018)102 I.J. Cabrillo, A. Calderon, B. Chazin Quero, J. Duarte Campderros, M. Fernandez,
P.J. Fern´andez Manteca, J. Garcia-Ferrero, A. Garc´ıa Alonso, G. Gomez, A. Lopez Virto,
J. Marco, C. Martinez Rivero, P. Martinez Ruiz del Arbol, F. Matorras, J. Piedra Gomez,
C. Prieels, T. Rodrigo, A. Ruiz-Jimeno, L. Scodellaro, N. Trevisani, I. Vila, R. Vilar
Cortabitarte C. Prieels, T. Rodrigo, A. Ruiz-Jimeno, L. Scodellaro, N. Trevisani, I. Vila, R. Vilar
Cortabitarte CERN, European Organization for Nuclear Research, Geneva, Switzer CERN, European Organization for Nuclear Research, Geneva, Switzerland
D. Abbaneo, B. Akgun, E. Auffray, P. Baillon, A.H. Ball, D. Barney, J. Bendavid,
M. Bianco, A. Bocci, C. Botta, T. Camporesi, R. Castello, M. Cepeda, G. Cerminara,
E. Chapon, Y. Chen, D. d’Enterria, A. Dabrowski, V. Daponte, A. David, M. De Gruttola,
A. De Roeck, N. Deelen, M. Dobson, T. du Pree, M. D¨unser, N. Dupont, A. Elliott-Peisert,
P. Everaerts, F. Fallavollita, G. Franzoni, J. Fulcher, W. Funk, D. Gigi, A. Gilbert, K. Gill,
F. Glege, D. Gulhan, J. Hegeman, V. Innocente, A. Jafari, P. Janot, O. Karacheban20,
J. Kieseler, V. Kn¨unz, A. Kornmayer, M.J. Kortelainen, M. Krammer1, C. Lange, P. Lecoq,
C. Louren¸co, M.T. Lucchini, L. Malgeri, M. Mannelli, A. Martelli, F. Meijers, J.A. Merlin,
S. Mersi, E. Meschi, P. Milenovic46, F. Moortgat, M. Mulders, H. Neugebauer, J. Ngadiuba,
S. Orfanelli, L. Orsini, L. Pape, E. Perez, M. Peruzzi, A. Petrilli, G. Petrucciani, A. Pfeiffer,
M. Pierini, F.M. Pitters, D. Rabady, A. Racz, T. Reis, G. Rolandi47, M. Rovere, H. Sakulin,
C. Sch¨afer, C. Schwick, M. Seidel, M. Selvaggi, A. Sharma, P. Silva, P. Sphicas48, A. Stakia,
J. Steggemann, M. Stoye, M. Tosi, D. Treille, A. Tsirou, V. Veckalns49, M. Verweij,
W.D. Zeuner J. Kieseler, V. Kn¨unz, A. Kornmayer, M.J. Kortelainen, M. S. Mersi, E. Meschi, P. Milenovic46, F. Moortgat, M. Mulders, H. Neugebauer, J. Ngadiu S. Orfanelli, L. Orsini, L. Pape, E. Perez, M. Peruzzi, A. Petrilli, G. Petrucciani, A. Pfeiffe M. Pierini, F.M. Pitters, D. Rabady, A. Racz, T. Reis, G. Rolandi47, M. Rovere, H. Sakuli C. Sch¨afer, C. Schwick, M. Seidel, M. Selvaggi, A. Sharma, P. Silva, P. Sphicas48, A. Staki J. Steggemann, M. Stoye, M. Tosi, D. Treille, A. Tsirou, V. Veckalns49, M. Moscow, Russia Verweij,
W.D. Zeuner Paul Scherrer Institut, Villigen, Switzerland Paul Scherrer Institut, Villigen, Switzerland W. Bertl†, L. Caminada50, K. Deiters, W. Erdmann, R. Horisberger, Q. Ingram,
H.C. Kaestli, D. Kotlinski, U. Langenegger, T. Rohe, S.A. Wiederkehr ETH Zurich - Institute for Particle Physics and Astrophysics (IPA),
Zurich,
Switzerland M. Backhaus, L. B¨ani, P. Berger, B. Casal, G. Dissertori, M. Dittmar, M. Doneg`a, C. Dor-
fer, C. Grab, C. Heidegger, D. Hits, J. Hoss, G. Kasieczka, T. Klijnsma, W. Lustermann,
B. Mangano, M. Marionneau, M.T. Meinhard, D. Meister, F. Micheli, P. Musella, F. Nessi-
Tedaldi, F. Pandolfi, J. Pata, F. Pauss, G. Perrin, L. Perrozzi, M. Quittnat, M. Reichmann,
D.A. Sanz Becerra, M. Sch¨onenberger, L. Shchutska, V.R. Tavolaro, K. Theofilatos,
M.L. Vesterbacka Olsson, R. Wallny, D.H. Zhu – 28 – Universit¨at Z¨urich, Zurich, Switzerland National Central University, Chung-Li, Taiwan V. Candelise, Y.H. Chang, K.y. Cheng, T.H. Doan, Sh. Jain, R. Khurana, C.M. Kuo,
W. Lin, A. Pozdnyakov, S.S. Yu Universit¨at Z¨urich, Zurich, Switzerland T.K. Aarrestad, C. Amsler51, M.F. Canelli, A. De Cosa, R. Del Burgo, S. Donato,
C. Galloni, T. Hreus, B. Kilminster, D. Pinna, G. Rauco, P. Robmann, D. Salerno,
K. Schweiger, C. Seitz, Y. Takahashi, A. Zucchetta National Central University, Chung-Li, Taiwan National Taiwan University (NTU), Taipei, Taiwan National Taiwan University (NTU), Taipei, Taiwan JHEP06(2018)102 Arun Kumar, P. Chang, Y. Chao, K.F. Chen, P.H. Chen, F. Fiori, W.-S. Hou, Y. Hsiung,
Y.F. Liu, R.-S. Lu, E. Paganis, A. Psallidas, A. Steen, J.f. Tsai Chulalongkorn University, Faculty of Science, Department of Physics, Bangkok,
Thailand B. Asavapibhop, K. Kovitanggoon, G. Singh, N. Srimanobhas C¸ ukurova University, Physics Department, Science and Art Faculty, Adana,
Turkey A. Bat, F. Boran, S. Cerci52, S. Damarseckin, Z.S. Demiroglu, C. Dozen, I. Dumanoglu,
S. Girgis, G. Gokbulut, Y. Guler, I. Hos53, E.E. Kangal54, O. Kara, A. Kayis Topaksu,
U. Kiminsu, M. Oglakci, G. Onengut, K. Ozdemir55, D. Sunar Cerci52, B. Tali52, U.G. Tok,
S. Turkcapar, I.S. Zorbakir, C. Zorbilmez Middle East Technical University, Physics Department, Ankara, Turkey
G. Karapinar56, K. Ocalan57, M. Yalvac, M. Zeyrek Bogazici University, Istanbul, Turkey Bogazici University, Istanbul, Turkey
E. G¨ulmez, M. Kaya58, O. Kaya59, S. Tekten, E.A. Yetkin60 E. G¨ulmez, M. Kaya58, O. Kaya59, S. Tekten, E.A. Yetkin60 E. G¨ulmez, M. Kaya58, O. Kaya59, S. Tekten, E.A. Yetkin60 Istanbul Technical University, Istanbul, Turkey
M.N. Agaras, S. Atay, A. Cakir, K. Cankocak, Y. Komurcu Istanbul Technical University, Istanbul, Turkey M.N. Agaras, S. Atay, A. Cakir, K. Cankocak, Y. Komurcu
Institute for Scintillation Materials of National Academy of Science of Ukraine,
Kharkov, Ukraine
B. Grynyov
National Scientific Center, Kharkov Institute of Physics and Technology,
Kharkov, Ukraine
L. Levchuk
University of Bristol, Bristol, United Kingdom
F. Ball, L. Beck, J.J. Brooke, D. Burns, E. Clement, D. Cussans, O. Davignon, H. Flacher,
J. Goldstein, G.P. Heath, H.F. Heath, L. Kreczko, D.M. Newbold61, S. Paramesvaran,
T. Sakuma, S. Seif El Nasr-storey, D. Smith, V.J. Smith Institute for Scintillation Materials of National Academy of Science of Ukraine,
Kharkov, Ukraine
B. Grynyov Institute for Scintillation Materials of National Academy of Science of Ukraine,
Kharkov, Ukraine
B. Grynyov
National Scientific Center
Kharkov Institute of Physics and Technology National Scientific Center, Kharkov Institute of Physics and Technology,
Kharkov, Ukraine
L. Levchuk National Scientific Center, Kharkov Institute of Physics and Technology,
Kharkov, Ukraine
L. Levchuk University of Bristol, Bristol, United Kingdom
F. Ball, L. Beck, J.J. Brooke, D. Burns, E. Clement, D. Cussans, O. Davignon, H. Flacher,
J. Goldstein, G.P. Heath, H.F. Heath, L. Kreczko, D.M. Newbold61, S. Paramesvaran,
T. Sakuma, S. Seif El Nasr-storey, D. Smith, V.J. Smith J. Goldstein, G.P. Heath, H.F. Heath, L. Kreczko, D.M. Newbold
, S. Paramesvaran,
T. Sakuma, S. Seif El Nasr-storey, D. National Taiwan University (NTU), Taipei, Taiwan Smith, V.J. Smith – 29 – Rutherford Appleton Laboratory, Didcot, United Kingdom
K.W. Bell, A. Belyaev62, C. Brew, R.M. Brown, L. Calligaris, D. Cieri, D.J.A. Cockerill,
J.A. Coughlan, K. Harder, S. Harper, J. Linacre, E. Olaiya, D. Petyt, C.H. Shepherd-
Themistocleous, A. Thea, I.R. Tomalin, T. Williams, W.J. Womersley Imperial College, London, United Kingdom Imperial College, London, United Kingdom G. Auzinger, R. Bainbridge, P. Bloch, J. Borg, S. Breeze, O. Buchmuller, A. Bundock,
S. Casasso, M. Citron, D. Colling, L. Corpe, P. Dauncey, G. Davies, M. Della Negra,
R. Di Maria, Y. Haddad, G. Hall, G. Iles, T. James, R. Lane, C. Laner, L. Lyons,
A.-M. Magnan, S. Malik, L. Mastrolorenzo, T. Matsushita, J. Nash63, A. Nikitenko6,
V. Palladino, M. Pesaresi, D.M. Raymond, A. Richards, A. Rose, E. Scott, C. Seez,
A. Shtipliyski, S. Summers, A. Tapper, K. Uchida, M. Vazquez Acosta64, T. Virdee17,
N. Wardle, D. Winterbottom, J. Wright, S.C. Zenz G. Auzinger, R. Bainbridge, P. Bloch, J. Borg, S. Breeze, O. Buchmuller, A. Bundoc S. Casasso, M. Citron, D. Colling, L. Corpe, P. Dauncey, G. Davies, M. Della Negr JHEP06(2018)102 V. Palladino, M. Pesaresi, D.M. Raymond, A. Richards, A. Rose, E. Scott, C. Seez,
A. Shtipliyski, S. Summers, A. Tapper, K. Uchida, M. Vazquez Acosta64, T. Virdee17,
N. Wardle, D. Winterbottom, J. Wright, S.C. Zenz Brunel University, Uxbridge, United Kingdom
J.E. Cole, P.R. Hobson, A. Khan, P. Kyberd, A. Morton, I.D. Reid, L. Teodorescu, S. Zahid Baylor University, Waco, U.S.A. Baylor University, Waco, U.S.A. A. Borzou, K. Call, J. Dittmann, K. Hatakeyama, H. Liu, N. Pastika, C. Smith A. Borzou, K. Call, J. Dittmann, K. Hatakeyama, H. Liu, N. Pastika, C. Smith Catholic University of America, Washington DC, U.S.A. R. Bartek, A. Dominguez The University of Alabama, Tuscaloosa, U.S.A. A. Buccilli, S.I. Cooper, C. Henderson, P. Rumerio, C. West The University of Alabama, Tuscaloosa, U.S.A. A. Buccilli, S.I. Cooper, C. Henderson, P. Rumerio, C. West Boston University, Boston, U.S.A. D. Arcaro, A. Avetisyan, T. Bose, D. Gastler, D. Rankin, C. Richardson, J. Rohlf, L. Sulak,
D. Zou Boston University, Boston, U.S.A. D. Arcaro, A. Avetisyan, T. Bose, D. Gastler, D. Rankin, C. Richardson, J. Rohlf, L. Sulak,
D. Zou Brown University, Providence, U.S.A. Fermi National Accelerator Laboratory, Batavia, U.S.A. Fermi National Accelerator Laboratory, Batavia, U.S.A. S. Abdullin, M. Albrow, M. Alyari, G. Apollinari, A. Apresyan, A. Apyan, S. Banerjee,
L.A.T. Bauerdick, A. Beretvas, J. Berryhill, P.C. Bhat, G. Bolla†, K. Burkett, J.N. But-
ler, A. Canepa, G.B. Cerati, H.W.K. Cheung, F. Chlebana, M. Cremonesi, J. Duarte,
V.D. Elvira, J. Freeman, Z. Gecse, E. Gottschalk, L. Gray, D. Green, S. Gr¨unendahl,
O. Gutsche, J. Hanlon, R.M. Harris, S. Hasegawa, J. Hirschauer, Z. Hu, B. Jayatilaka,
S. Jindariani, M. Johnson, U. Joshi, B. Klima, B. Kreis, S. Lammel, D. Lincoln, R. Lipton,
M. Liu, T. Liu, R. Lopes De S´a, J. Lykken, K. Maeshima, N. Magini, J.M. Marraffino,
D. Mason, P. McBride, P. Merkel, S. Mrenna, S. Nahn, V. O’Dell, K. Pedro, O. Prokofyev,
G. Rakness, L. Ristori, A. Savoy-Navarro66, B. Schneider, E. Sexton-Kennedy, A. Soha,
W.J. Spalding, L. Spiegel, S. Stoynev, J. Strait, N. Strobbe, L. Taylor, S. Tkaczyk,
N.V. Tran, L. Uplegger, E.W. Vaandering, C. Vernieri, M. Verzocchi, R. Vidal, M. Wang,
H.A. Weber, A. Whitbeck, W. Wu H.A. Weber, A. Whitbeck, W. Wu Brown University, Providence, U.S.A. Brown University, Providence, U.S.A. G. Benelli, D. Cutts, M. Hadley, J. Hakala, U. Heintz, J.M. Hogan, K.H.M. Kwok, E. Lair G. Benelli, D. Cutts, M. Hadley, J. Hakala, U. Heintz, J.M. Hogan, K.H.M. Kwok, E. Laird,
G. Landsberg, J. Lee, Z. Mao, M. Narain, J. Pazzini, S. Piperov, S. Sagir, R. Syarif, D. Yu G. Benelli, D. Cutts, M. Hadley, J. Hakala, U. Heintz, J.M. Hogan, K.H.M. Kwok, E. Laird,
G. Landsberg, J. Lee, Z. Mao, M. Narain, J. Pazzini, S. Piperov, S. Sagir, R. Syarif, D. Yu University of California, Davis, Davis, U.S.A. R. Band, C. Brainerd, R. Breedon, D. Burns, M. Calderon De La Barca Sanchez,
M. Chertok, J. Conway, R. Conway, P.T. Cox, R. Erbacher, C. Flores, G. Funk, W. Ko,
R. Lander, C. Mclean, M. Mulhearn, D. Pellett, J. Pilot, S. Shalhout, M. Shi, J. Smith,
D. Stolp, D. Taylor, K. Tos, M. Tripathi, Z. Wang University of California, Los Angeles, U.S.A. M. Bachtis, C. Bravo, R. Cousins, A. Dasgupta, A. Florent, J. Hauser, M. Ignatenko,
N. Mccoll, S. Regnard, D. Saltzberg, C. Schnaible, V. Valuev y
,
g
,
. Bachtis, C. Bravo, R. Cousins, A. Dasgupta, A. Florent, J. Hauser, M. Ignatenko,
Mccoll, S. Regnard, D. Saltzberg, C. Schnaible, V. Valuev University of California, Riverside, Riverside, U.S.A. E. Bouvier, K. Burt, R. Clare, J. Ellison, J.W. Gary, S.M.A. Ghiasi Shirazi, G. Hanson,
G. Karapostoli, E. Kennedy, F. Lacroix, O.R. Long, M. Olmedo Negrete, M.I. Paneva,
W. Si, L. Wang, H. Wei, S. Wimpenny, B. R. Yates G. Karapostoli, E. Kennedy, F. Lacroix, O.R. Long, M. Olmedo Negrete, M.I. Paneva,
W. Si, L. Wang, H. Wei, S. Wimpenny, B. R. Yates – 30 – University of California, San Diego, La Jolla, U.S.A. J.G. Branson, S. Cittolin, M. Derdzinski, R. Gerosa, D. Gilbert, B. Hashemi, A. Holzner,
D. Klein, G. Kole, V. Krutelyov, J. Letts, M. Masciovecchio, D. Olivito, S. Padhi,
M. Pieri, M. Sani, V. Sharma, S. Simon, M. Tadel, A. Vartak, S. Wasserbaech65, J. Wood,
F. W¨urthwein, A. Yagil, G. Zevi Della Porta University of California, Santa Barbara - Department of Physics, Santa Bar-
bara, U.S.A. N. Amin, R. Bhandari, J. Bradmiller-Feld, C. Campagnari, A. Dishaw, V. Dutta, M. Franco
Sevilla, L. Gouskos, R. Heller, J. Incandela, A. Ovcharova, H. Qu, J. Richman, D. Stuart, University of California, Santa Barbara - Department of Physics, Santa Bar-
bara, U.S.A. D. Acosta, P. Avery, P. Bortignon, D. Bourilkov, A. Brinkerhoff, A. Carnes, M. Carver,
D. Curry, R.D. Field, I.K. Furic, S.V. Gleyzer, B.M. Joshi, J. Konigsberg, A. Korytov, Cornell University, Ithaca, U.S.A. Cornell University, Ithaca, U.S.A. J. Alexander, J. Chaves, Y. Cheng, J. Chu, S. Dittmer, K. Mcdermott, N. Mirman,
J.R. Patterson, D. Quach, A. Rinkevicius, A. Ryd, L. Skinnari, L. Soffi, S.M. Tan, Z. Tao,
J. Thom, J. Tucker, P. Wittich, M. Zientek J. Thom, J. Tucker, P. Wittich, M. Zientek Fermi National Accelerator Laboratory, Batavia, U.S.A. California Institute of Technology, Pasadena, U.S.A. Carnegie Mellon University, Pittsburgh, U.S.A. M.B. Andrews, T. Ferguson, T. Mudholkar, M. Paulini, J. Russ, M. Sun, H. Vogel,
I. Vorobiev, M. Weinberg University of Colorado Boulder, Boulder, U.S.A. y
,
,
J.P. Cumalat, W.T. Ford, F. Jensen, A. Johnson, M. Krohn, S. Leontsinis, E. Macdonald,
T. Mulholland, K. Stenson, S.R. Wagner Brown University, Providence, U.S.A. University of California, Santa Barbara - Department of Physics, Santa Bar-
bara, U.S.A. N. Amin, R. Bhandari, J. Bradmiller-Feld, C. Campagnari, A. Dishaw, V. Dutta, M. Franco
Sevilla, L. Gouskos, R. Heller, J. Incandela, A. Ovcharova, H. Qu, J. Richman, D. Stuart,
I. Suarez, J. Yoo N. Amin, R. Bhandari, J. Bradmiller-Feld, C. Campagnari, A. Dishaw, V. Dutta, M. Franco
Sevilla, L. Gouskos, R. Heller, J. Incandela, A. Ovcharova, H. Qu, J. Richman, D. Stuart,
I. Suarez, J. Yoo JHEP06(2018)102 I. Suarez, J. Yoo California Institute of Technology, Pasadena, U.S.A. California Institute of Technology, Pasadena, U.S.A. D. Anderson, A. Bornheim, J. Bunn, I. Dutta, J.M. Lawhorn, H.B. Newman, T. Q. Nguyen,
C. Pena, M. Spiropulu, J.R. Vlimant, R. Wilkinson, S. Xie, Z. Zhang, R.Y. Zhu Florida Institute of Technology, Melbourne, U.S.A. Florida Institute of Technology, Melbourne, U.S.A. JHEP06(2018)102 M.M. Baarmand, V. Bhopatkar, S. Colafranceschi, M. Hohlmann, D. Noonan, T. Roy,
F. Yumiceva University of Illinois at Chicago (UIC), Chicago, U.S.A. M.R. Adams, L. Apanasevich, D. Berry, R.R. Betts, R. Cavanaugh, X. Chen, O. Evdoki-
mov, C.E. Gerber, D.A. Hangal, D.J. Hofman, K. Jung, J. Kamin, I.D. Sandoval Gonzalez,
M.B. Tonjes, H. Trauger, N. Varelas, H. Wang, Z. Wu, J. Zhang The University of Iowa, Iowa City, U.S.A. B. Bilki67, W. Clarida, K. Dilsiz68, S. Durgut, R.P. Gandrajula, M. Haytmyradov,
V. Khristenko, J.-P. Merlo, H. Mermerkaya69, A. Mestvirishvili, A. Moeller, J. Nachtman,
H. Ogul70, Y. Onel, F. Ozok71, A. Penzo, C. Snyder, E. Tiras, J. Wetzel, K. Yi Johns Hopkins University, Baltimore, U.S.A. B. Blumenfeld, A. Cocoros, N. Eminizer, D. Fehling, L. Feng, A.V. Gritsan, P. Maksimovic,
J. Roskes, U. Sarica, M. Swartz, M. Xiao, C. You The University of Kansas, Lawrence, U.S.A. A. Al-bataineh, P. Baringer, A. Bean, S. Boren, J. Bowen, J. Castle, S. Khalil, A. Kropivnit-
skaya, D. Majumder, W. Mcbrayer, M. Murray, C. Rogan, C. Royon, S. Sanders,
E. Schmitz, J.D. Tapia Takaki, Q. Wang Kansas State University, Manhattan, U.S.A. A. Ivanov, K. Kaadze, Y. Maravin, A. Mohammadi, L.K. Saini, N. Skhirtladze Lawrence Livermore National Laboratory, Livermore, U.S.A. F. Rebassoo, D. Wright University of Maryland, College Park, U.S.A. A. Baden, O. Baron, A. Belloni, S.C. Eno, Y. Feng, C. Ferraioli, N.J. Hadley, S. Jabeen,
G.Y. Jeng, R.G. Kellogg, J. Kunkle, A.C. Mignerey, F. Ricci-Tam, Y.H. Shin, A. Skuja,
S.C. Tonwar Massachusetts Institute of Technology, Cambridge, U.S.A. University of Florida, Gainesville, U.S.A. D. Acosta, P. Avery, P. Bortignon, D. Bourilkov, A. Brinkerhoff, A. Carnes, M. Carver,
D. Curry, R.D. Field, I.K. Furic, S.V. Gleyzer, B.M. Joshi, J. Konigsberg, A. Korytov, – 31 – K. Kotov, P. Ma, K. Matchev, H. Mei, G. Mitselmakher, K. Shi, D. Sperka, N. Terentyev,
L. Thomas, J. Wang, S. Wang, J. Yelton L. Thomas, J. Wang, S. Wang, J. Yelton Florida International University, Miami, U.S.A. Y.R. Joshi, S. Linn, P. Markowitz, J.L. Rodriguez Florida State University, Tallahassee, U.S.A. Florida State University, Tallahassee, U.S.A. A. Ackert, T. Adams, A. Askew, S. Hagopian, V. Hagopian, K.F. Johnson, T. Kolberg,
G. Martinez, T. Perry, H. Prosper, A. Saha, A. Santra, V. Sharma, R. Yohay orida State University, Tallahassee, U.S.A. Ackert, T. Adams, A. Askew, S. Hagopian, V. Hagopian, K.F. Johnson, T. Kolberg,
M
i
T P
H P
A S h
A S
V Sh
R Y h A. Ackert, T. Adams, A. Askew, S. Hagopian, V. Hagopian, K.F. Johnson, T. Kolber G. Martinez, T. Perry, H. Prosper, A. Saha, A. Santra, V. Sharma, R. Yohay Massachusetts Institute of Technology, Cambridge, U.S.A. Loukas, N. Marinelli, F. Meng, C. Mueller, Y. Musienko38, M. Planer, K. Lannon, W. Li, N. Loukas, N. Marinelli, F. Meng, C. Mueller, Y. Musienko38, M. Plane A. Reinsvold, R. Ruchti, P. Siddireddy, G. Smith, S. Taroni, M. Wayne, A. Wightman,
M. Wolf, A. Woodard The Ohio State University, Columbus, U.S.A. J. Alimena, L. Antonelli, B. Bylsma, L.S. Durkin, S. Flowers, B. Francis, A. Hart, C. Hill,
W. Ji, T.Y. Ling, B. Liu, W. Luo, B.L. Winer, H.W. Wulsin Princeton University, Princeton, U.S.A. Princeton University, Princeton, U.S.A. S. Cooperstein, O. Driga, P. Elmer, J. Hardenbrook, P. Hebda, S. Higginbotham,
A. Kalogeropoulos, D. Lange, J. Luo, D. Marlow, K. Mei, I. Ojalvo, J. Olsen, C. Palmer,
P. Pirou´e, D. Stickland, C. Tully S. Cooperstein, O. Driga, P. Elmer, J. Hardenbrook, P. Hebda, S. Higginbotham,
A. Kalogeropoulos, D. Lange, J. Luo, D. Marlow, K. Mei, I. Ojalvo, J. Olsen, C. Palmer,
P. Pirou´e, D. Stickland, C. Tully Massachusetts Institute of Technology, Cambridge, U.S.A. D. Abercrombie, B. Allen, V. Azzolini, R. Barbieri, A. Baty, G. Bauer, R. Bi, S. Brandt,
W. Busza, I.A. Cali, M. D’Alfonso, Z. Demiragli, G. Gomez Ceballos, M. Goncharov,
P. Harris, D. Hsu, M. Hu, Y. Iiyama, G.M. Innocenti, M. Klute, D. Kovalskyi, Y.-J. Lee,
A. Levin, P.D. Luckey, B. Maier, A.C. Marini, C. Mcginn, C. Mironov, S. Narayanan, P. Harris, D. Hsu, M. Hu, Y. Iiyama, G.M. Innocenti, M. Klute, D. Kovalskyi, Y.-J. Lee,
A. Levin, P.D. Luckey, B. Maier, A.C. Marini, C. Mcginn, C. Mironov, S. Narayanan, A. Levin, P.D. Luckey, B. Maier, A.C. Marini, C. Mcginn, C. Mironov, S. Narayanan, – 32 – X. Niu, C. Paus, C. Roland, G. Roland, J. Salfeld-Nebgen, G.S.F. Stephans, K. Sumorok,
K. Tatar, D. Velicanu, J. Wang, T.W. Wang, B. Wyslouch X. Niu, C. Paus, C. Roland, G. Roland, J. Salfeld-Nebgen, G.S.F. Stephans, K. Sumoro University of Minnesota, Minneapolis, U.S.A. A.C. Benvenuti, R.M. Chatterjee, A. Evans, P. Hansen, J. Hiltbrand, S. Kalafut,
Y. Kubota, Z. Lesko, J. Mans, S. Nourbakhsh, N. Ruckstuhl, R. Rusack, J. Turkewitz,
M.A. Wadud University of Mississippi, Oxford, U.S.A. J.G. Acosta, S. Oliveros JHEP06(2018)102 University of Nebraska-Lincoln, Lincoln, U.S.A. E. Avdeeva, K. Bloom, D.R. Claes, C. Fangmeier, F. Golf, R. Gonzalez Suarez, R. Ka-
malieddin, I. Kravchenko, J. Monroy, J.E. Siado, G.R. Snow, B. Stieger State University of New York at Buffalo, Buffalo, U.S.A. J. Dolen, A. Godshalk, C. Harrington, I. Iashvili, D. Nguyen, A. Parker, S. Rappoccio,
B. Roozbahani Northeastern University, Boston, U.S.A. Northeastern University, Boston, U.S.A. G. Alverson, E. Barberis, C. Freer, A. Hortiangtham, A. Massironi, D.M. Morse, T. Ori-
moto, R. Teixeira De Lima, T. Wamorkar, B. Wang, A. Wisecarver, D. Wood G. Alverson, E. Barberis, C. Freer, A. Hortiangtham, A. Massironi, D.M. Morse, T. Ori-
moto, R. Teixeira De Lima, T. Wamorkar, B. Wang, A. Wisecarver, D. Wood Northwestern University, Evanston, U.S.A. S. Bhattacharya, O. Charaf, K.A. Hahn, N. Mucia, N. Odell, M.H. Schmitt, K. Sung,
M. Trovato, M. Velasco University of Notre Dame, Notre Dame, U.S.A. R. Bucci, N. Dev, M. Hildreth, K. Hurtado Anampa, C. Jessop, D.J. Karmgard, N. Kellams,
K. Lannon, W. Li, N. Loukas, N. Marinelli, F. Meng, C. Mueller, Y. Musienko38, M. Planer, R. Bucci, N. Dev, M. Hildreth, K. Hurtado Anampa, C. Jessop, D.J. Karmgard, N. Kellam R. Bucci, N. Dev, M. Hildreth, K. Hurtado Anampa, C. Jessop, D.J. Karmgard, N. Kellams,
K. Lannon, W. Li, N. University of Puerto Rico, Mayaguez, U.S.A.
S. Malik, S. Norberg University of Puerto Rico, Mayaguez, U.S.A. S. Malik, S. Norberg University of Puerto Rico, Mayaguez, U.S.A. S. Malik, S. Norberg Purdue University, West Lafayette, U.S.A. A. Barker, V.E. Barnes, S. Das, S. Folgueras, L. Gutay, M. Jones, A.W. Jung, A. Khati-
wada, D.H. Miller, N. Neumeister, C.C. Peng, H. Qiu, J.F. Schulte, J. Sun, F. Wang,
R. Xiao, W. Xie – 33 – Purdue University Northwest, Hammond, U.S.A. T. Cheng, N. Parashar, J. Stupak Rice University, Houston, U.S.A. Z. Chen, K.M. Ecklund, S. Freed, F.J.M. Geurts, M. Guilbaud, M. Kilpatrick, W. Li,
B. Michlin, B.P. Padley, J. Roberts, J. Rorie, W. Shi, Z. Tu, J. Zabel, A. Zhang University of Rochester, Rochester, U.S.A. A. Bodek, P. de Barbaro, R. Demina, Y.t. Duh, T. Ferbel, M. Galanti, A. Garcia-Bellido,
J. Han, O. Hindrichs, A. Khukhunaishvili, K.H. Lo, P. Tan, M. Verzetti JHEP06(2018)102 The Rockefeller University, New York, U.S.A. R. Ciesielski, K. Goulianos, C. Mesropian Rutgers, The State University of New Jersey, Piscataway, U.S.A. Rutgers, The State University of New Jersey, Piscataway, U.S.A. A. Agapitos, J.P. Chou, Y. Gershtein, T.A. G´omez Espinosa, E. Halkiadakis, M. Heindl,
E. Hughes, S. Kaplan, R. Kunnawalkam Elayavalli, S. Kyriacou, A. Lath, R. Montalvo,
K. Nash, M. Osherson, H. Saka, S. Salur, S. Schnetzer, D. Sheffield, S. Somalwar, R. Stone,
S. Thomas, P. Thomassen, M. Walker University of Tennessee, Knoxville, U.S.A. University of Tennessee, Knoxville, U.S.A. A.G. Delannoy, J. Heideman, G. Riley, K. Rose, S. Spanier, K. Thapa A.G. Delannoy, J. Heideman, G. Riley, K. Rose, S. Spanier, K. Thapa Texas A&M University, College Station, U.S.A. O. Bouhali72, A. Castaneda Hernandez72, A. Celik, M. Dalchenko, M. De Mattia, A. Del-
gado, S. Dildick, R. Eusebi, J. Gilmore, T. Huang, T. Kamon73, R. Mueller, Y. Pakhotin,
R. Patel, A. Perloff, L. Perni`e, D. Rathjens, A. Safonov, A. Tatarinov, K.A. Ulmer Texas Tech University, Lubbock, U.S.A. Texas Tech University, Lubbock, U.S.A. N. Akchurin, J. Damgov, F. De Guio, P.R. Dudero, J. Faulkner, E. Gurpinar, S. Kunori, N. Akchurin, J. Damgov, F. De Guio, P.R. Dudero, J. Faulkner, E. Gurpinar, S. Kunori,
K. Lamichhane, S.W. Lee, T. Mengke, S. Muthumuni, T. Peltola, S. Undleeb, I. Volobouev,
Z. Wang K. Lamichhane, S.W. Lee, T. Mengke, S. Muthumuni, T. Peltola, S. Undleeb, I. Volobouev,
Z. Wang Z. Wang Vanderbilt University, Nashville, U.S.A. Vanderbilt University, Nashville, U.S.A. S. Greene, A. Gurrola, R. Janjam, W. Johns, C. Maguire, A. Melo, H. Ni, K. University of Puerto Rico, Mayaguez, U.S.A.
S. Malik, S. Norberg Padeken, Vanderbilt University, Nashville, U.S.A. S. Greene, A. Gurrola, R. Janjam, W. Johns, C. Maguire, A. Melo, H. Ni, K. Padeken,
P. Sheldon, S. Tuo, J. Velkovska, Q. Xu S. Greene, A. Gurrola, R. Janjam, W. Johns, C. Maguire, A. Melo, H. Ni, K. Padeke
P. Sheldon, S. Tuo, J. Velkovska, Q. Xu University of Virginia, Charlottesville, U.S.A. M.W. Arenton, P. Barria, B. Cox, R. Hirosky, M. Joyce, A. Ledovskoy, H. Li, C. Neu,
T. Sinthuprasith, Y. Wang, E. Wolfe, F. Xia Wayne State University, Detroit, U.S.A. R. Harr, P.E. Karchin, N. Poudyal, J. Sturdy, P. Thapa, S. Zaleski University of Wisconsin - Madison, Madison, WI, U.S.A. University of Wisconsin - Madison, Madison, WI, U.S.A. University of Wisconsin - Madison, Madison, WI, U.S.A. M. Brodski, J. Buchanan, C. Caillol, D. Carlsmith, S. Dasu, L. Dodd, S. Duric, B. Gomber,
M. Grothe, M. Herndon, A. Herv´e, U. Hussain, P. Klabbers, A. Lanaro, A. Levine, K. Long,
R. Loveless, V. Rekovic, T. Ruggles, A. Savin, N. Smith, W.H. Smith, N. Woods M. Brodski, J. Buchanan, C. Caillol, D. Carlsmith, S. Dasu, L. Dodd, S. Duric, B. Gomb M. Brodski, J. Buchanan, C. Caillol, D. Carlsmith, S. Dasu, L. Dodd, S. Duric, B. Gomber,
M. Grothe, M. Herndon, A. Herv´e, U. Hussain, P. Klabbers, A. Lanaro, A. Levine, K. Long,
R. Loveless, V. Rekovic, T. Ruggles, A. Savin, N. Smith, W.H. Smith, N. Woods M. Grothe, M. Herndon, A. Herv´e, U. Hussain, P. Klabbers, A. Lanaro, A. Levine, K. Long, R. Loveless, V. Rekovic, T. Ruggles, A. Savin, N. Smith, W.H. Smith, N. Woods R. Loveless, V. Rekovic, T. Ruggles, A. Savin, N. Smith, W.H. Smith, N. University of Puerto Rico, Mayaguez, U.S.A.
S. Malik, S. Norberg Woods – 34 – 1: Also at Vienna University of Technology, Vienna, Austria 1: Also at Vienna University of Technology, Vienna, Austria 2: Also at IRFU, CEA, Universit´e Paris-Saclay, Gif-sur-Yvette, France 2: Also at IRFU, CEA, Universit´e Paris-Saclay, Gif-sur-Yvette, France 3: Also at Universidade Estadual de Campinas, Campinas, Brazil 4: Also at Federal University of Rio Grande do Sul, Porto Alegre, Brazil 5: Also at Universit´e Libre de Bruxelles, Bruxelles, Belgium 6: Also at Institute for Theoretical and Experimental Physics, Moscow, Russia 7: Also at Joint Institute for Nuclear Research, Dubna, Russia 7: Also at Joint Institute for Nuclear Research 8: Also at Helwan University, Cairo, Egypt 9: Now at Zewail City of Science and Technology, Zewail, Eg 10: Now at Fayoum University, El-Fayoum, Egypt JHEP06(2018)102 11: Also at British University in Egypt, Cairo, Egypt 12: Now at Ain Shams University, Cairo, Egypt 13: Also at Department of Physics, King Abdulaziz University, Jeddah, Saudi Arabia 13: Also at Department of Physics, King Abdulaziz University, Jeddah, Saudi Arab 14: Also at Universit´e de Haute Alsace, Mulhouse, France 14: Also at Universit´e de Haute Alsace, Mulhouse, France 15: Also at Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University,
Moscow, Russia 16: Also at Tbilisi State University, Tbilisi, Georgia 17: Also at CERN, European Organization for Nuclear Research, Geneva, Switzerland 17: Also at CERN, European Organization for Nuclear Research, Geneva, Switzerland 18: Also at RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany 18: Also at RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany 19: Also at University of Hamburg, Hamburg, Germany 19: Also at University of Hamburg, Hamburg, Germany 20: Also at Brandenburg University of Technology, Cottbus, Germany 20: Also at Brandenburg University of Technology, Cottbus, Germany 21: Also at MTA-ELTE Lend¨ulet CMS Particle and Nuclear Physics Group, E¨otv¨os Lor´and 21: Also at MTA-ELTE Lend¨ulet CMS Particle and Nuclear Physics Group, E¨otv¨os Lor´and
University, Budapest, Hungary 21: Also at MTA-ELTE Lend¨ulet CMS Particle and Nuclear Physics Group, E¨otv¨os Lor´and
University Budapest Hungary 21: Also at MTA-ELTE Lend¨ulet CMS Particle and Nuclear Physics Group, E¨otv¨os Lor´and
University Budapest Hungary University, Budapest, Hungary 22: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary 22: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary 24: Also at Indian Institute of Technology Bhubaneswar, Bhubaneswar, India 24: Also at Indian Institute of Technology Bhubaneswar, Bhubaneswar, India 25: Also at Institute of Physics, Bhubaneswar, India 25: Also at Institute of Physics, Bhubaneswar, India 26: Also at Shoolini University, Solan, India 27: Also at University of Visva-Bharati, Santiniketan, India 27: Also at University of Visva-Bharati, Santiniketan, India 28: Also at University of Ruhuna, Matara, Sri Lanka 28: Also at University of Ruhuna, Matara, Sri Lanka 29: Also at Isfahan University of Technology, Isfahan, Iran 29: Also at Isfahan University of Technology, Isfahan, Iran 29: Also at Isfahan University of Technolo 30: Also at Yazd University, Yazd, Iran 31: Also at Plasma Physics Research Center, Science and Research Branch, Islamic Aza
University, Tehran, Iran University, Tehran, Iran 32: Also at Universit`a degli Studi di Siena, Siena, Italy 32: Also at Universit`a degli Studi di Siena, Siena, Italy 33: Also at INFN Sezione di Milano-Bicocca; Universit`a di Milano-Bicocca, Milano, Italy 33: Also at INFN Sezione di Milano-Bicocca; Universit`a di Milano-Bicocca, Milano, Italy 34: Also at International Islamic University of Malaysia, Kuala Lumpur, Malaysia 34: Also at International Islamic University of Malaysia, Kuala Lumpur, Malaysia 35: Also at Malaysian Nuclear Agency, MOSTI, Kajang, Malaysia 35: Also at Malaysian Nuclear Agency, MOSTI, Kajang, Malaysia 36: Also at Consejo Nacional de Ciencia y Tecnolog´ıa, Mexico city, Mexico 36: Also at Consejo Nacional de Ciencia y Tecnolog´ıa, Mexico city, Mexico t Warsaw University of Technology, Institute of E 37: Also at Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
38: Also at Institute for Nuclear Research, Moscow, Russia 38: Also at Institute for Nuclear Research, Moscow, Russia 38: Also at Institute for Nuclear Research, Moscow, Russia 39: Now
at
National
Research
Nuclear
University
’Moscow
Engineering
Physics
Insti-
tute’ (MEPhI), Moscow, Russia 39: Now
at
National
Research
Nuclear
University
’Moscow
Engineering
Physics
Insti-
tute’ (MEPhI), Moscow, Russia 40: Also at St. Petersburg State Polytechnical University, St. Petersburg, Russia 40: Also at St. Petersburg State Polytechnical University, St. Petersburg, Russia 41: Also at University of Florida, Gainesville, U.S.A. 42: Also at P.N. Lebedev Physical Institute, Moscow, Russia 43: Also at California Institute of Technology, Pasadena, U.S.A. – 35 – 44: Also at Budker Institute of Nuclear Physics, Novosibirsk, Russia 44: Also at Budker Institute of Nuclear Physics, Novosibirsk, Russia 45: Also at Faculty of Physics, University of Belgrade, Belgrade, Serbia 45: Also at Faculty of Physics, University of Belgrade, Belgrade, Serbia 46: Also at University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences,
Belgrade, Serbia 46: Also at University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences,
Belgrade, Serbia Belgrade, Serbia 47: Also at Scuola Normale e Sezione dell’INFN, Pisa, Italy 47: Also at Scuola Normale e Sezione dell’INFN, Pisa, Italy 48: Also at National and Kapodistrian University of Athens, Athens, Greece 48: Also at National and Kapodistrian University of Athens, Athens, Greece 49: Also at Riga Technical University, Riga, Latvia 50: Also at Universit¨at Z¨urich, Zurich, Switzerland 50: Also at Universit¨at Z¨urich, Zurich, Switzerland 51: Also at Stefan Meyer Institute for Subatomic Physics (SMI), Vienna, Austria 51: Also at Stefan Meyer Institute for Subatomic Physics (SMI), Vienna, Austria Also at Stefan Meyer Institute for Subatomic P 52: Also at Adiyaman University, Adiyaman, Turkey 53: Also at Istanbul Aydin University, Istanbul, Turkey JHEP06(2018)102 54: Also at Mersin University, Mersin, Turkey 55: Also at Piri Reis University, Istanbul, Turkey 56: Also at Izmir Institute of Technology, Izmir, Turkey 57: Also at Necmettin Erbakan University, Konya, Turkey 58: Also at Marmara University, Istanbul, Turkey 59: Also at Kafkas University, Kars, Turkey 60: Also at Istanbul Bilgi University, Istanbul, Turkey 61: Also at Rutherford Appleton Laboratory, Didcot, United Kingdom 62: Also at School of Physics and Astronomy, University of Southampton, Southampton, United
Kingdom 63: Also at Monash University, Faculty of Science, Clayton, Australia 64: Also at Instituto de Astrof´ısica de Canarias, La Laguna, Spain 65: Also at Utah Valley University, Orem, U.S.A. 66: Also at Purdue University, West Lafayette, U.S.A. 67: Also at Beykent University, Istanbul, Turkey 68: Also at Bingol University, Bingol, Turkey 69: Also at Erzincan University, Erzincan, Turkey 70: Also at Sinop University, Sinop, Turkey 71: Also at Mimar Sinan University, Istanbul, Istanbul, Turkey 71: Also at Mimar Sinan University, Istanbul, Istanbul, Turkey 71: Also at Mimar Sinan University, Istanbu 72: Also at Texas A&M University at Qatar, Doha, Qatar 72: Also at Texas A&M University at Qatar, Doha, Qatar 73: Also at Kyungpook National University, Daegu, Korea – 36 –
|
https://openalex.org/W2615246307
|
https://research.tees.ac.uk/files/7225997/Thalassemias_in_South_Asia.pdf
|
English
| null |
Thalassemias in South Asia: clinical lessons learnt from Bangladesh
|
Orphanet journal of rare diseases
| 2,017
|
cc-by
| 7,845
|
© The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. * Correspondence: sorowar.hossain@brfbd.org
1Biomedical Research Foundation, House #7, Apartment# 1A, Road# 1/B,
Banani, Chairman Bari, Dhaka-1213, Bangladesh
2Faculty of Basic Sciences, Bangladesh University of Health Sciences, Dhaka,
Bangladesh
Full list of author information is available at the end of the article Thalassemias in South Asia: clinical lessons
learnt from Bangladesh Mohammad Sorowar Hossain1,2,3*, Enayetur Raheem1, Tanvira Afroze Sultana1, Shameema Ferdous1, Nusrat Nahar4,
Sazia Islam5, Mohammad Arifuzzaman1, Mohammad Abdur Razzaque1,5, Rabiul Alam1, Sonia Aziz6, Hazera Khatun7,
Abdur Rahim4 and Manzur Morshed4 Abstract Thalassemias are emerging as a global public health concern. Due to remarkable success in the reduction of childhood
mortality by controlling infectious diseases in developing countries, thalassemias are likely to be a major public health
concern in the coming decades in South Asia. Despite the fact that Bangladesh lies in the world’s thalassemia belt, the
information on different aspects (epidemiology, clinical course, mortality, complications and treatment outcomes)
of thalassemias is lacking. In this comprehensive review, the aim is to to depict the epidemiological aspects of
thalassemias, mutation profile and current treatment and management practices in the country by sharing the
experience of dealing with 1178 cases over 2009–2014 time periods in a specialized thalassemia treatment centre. We have also discussed the preventative strategies of thalassemias from the context of Bangladesh which could be
effective for other developing countries. Keywords: Beta thalassemia, Hemoglobinopathies, Thalassemia trait, Beta thalassemia major, HbE beta thalassemia,
Non-transfusion dependent thalassemia, Transfusion dependent thalassemia, Bangladesh © The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link
the Creative Commons license and indicate if changes were made The Creative Commons Public Domain Dedication wa Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93
DOI 10.1186/s13023-017-0643-z Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93
DOI 10.1186/s13023-017-0643-z Background However,
these estimates must be interpreted with caution since
the data was mainly based on studies conducted in 1980,
and a small number of non-representative samples
obtained from treatment centers were analyzed [3]. The
only published report available on the prevalence of thal-
assemia among (n = 735) school children in Bangladesh
showed a 4.1% prevalence of the beta-thalassemia trait
and a 6.1% prevalence for the HbE trait [16]. The same
study revealed the regional variation of beta-thalassemia
carriers ranging from 2.9 to 8.1% and 2.4 to 16.5% for
HbE carriers. Among tribal children, the prevalence of
beta-thalassemia trait was almost identical but HbE was
much higher (41.7%). Another study with a small sample
size also observed similar (39–47%) prevalence rate of
HbE among a tribal population in Bangladesh [17]. approximately 30–48 million beta thalassemia carriers in
India
and
approximately
5–12
million
carriers
in
Pakistan with a carrier rate of 5–7% [2, 8]. Bangladesh is one of the most densely populated coun-
tries in the world, with a population of over 160 million
people. Over 70% of the population live in highly
resource-constrained rural areas [5], while most tertiary
hospitals are located in big cities, notably in Dhaka, the
capital city. Public hospitals are often overcrowded and
lack resources (such as specialized and basic medical
equipment, healthcare professionals and essential drugs)
[9]. On the contrary, some private clinics and hospitals
are relatively resourceful but these are not accessible to
the general population due to the associated costs. The
treatment drop-out rate among a population plagued by
poverty is expected to be very high, and is presumably
driven by lack of access, either due to lack of awareness
or income of patients seeking care on the demand side,
or inadequate expertise, facilities, knowledge, and infra-
structure from the supply side of health care. Bangladesh shares linguistic and socio-cultural com-
monalities with East Indian region, particularly West
Bengal. By and large, the genetic makeup is also closely
related in this part of the world [18] despite different
religious backgrounds [19]. Hence, the prevalence of
hemoglobinopathies in Bangladesh could be extrapo-
lated
from
population-based
studies
conducted
in
West Bengal. A recent large population-based study
(n = 50,487) in rural West Bengal revealed the carrier
rate of beta-thalassemia and HbE to be 6.61 and 2.78% re-
spectively [20]. Background Another recent study (n = 9990) estimated
the frequency of 3.64% for beta thalassemia traits and
3.92% for the HbE trait [6]. Taking all these factors into
account, the estimated prevalence of beta-thalassemia
carriers could be in the range of 3–6%, and 3–4% for HbE
in Bangladesh. Despite the fact that Bangladesh lies in the world’s thalas-
semia belt, the information on different aspects (epidemi-
ology,
clinical
course,
mortality,
complications
and
treatment outcomes) of thalassemias is lacking. A recent
study has revealed that the higher prevalence of anemia in
Bangladesh is not associated with iron deficiency [10]. The
nationwide prevalence of anemia (33.1% in children under
five years of age and 26% in women) was more than three
times higher than that of iron deficiency in children (10.7%)
and women (7.1%), suggesting other determining factors
for this unexpected scenario [10]. In this context, the role
of congenital Hb disorders along with micronutrient (such
as dietary iron, vitamin A, folate and Zn) deficiency could
explain this phenomenon [10]. A recent study has
indicated that about 28% of assessed rural women have
beta thalassemia or HbE [11]. Similar findings have been
reported for women and children of the thalassemia prone
Southeast-Asian country, Cambodia [12, 13]. It is a fact that most children with severe forms of
thalassemia (such as thalassemia major) usually die
under 5 years of age [1] and the average life expectancy
of patients suffering from thalassemias is about 30 years
[20], particularly in heavily resource constrained coun-
tries. Considering these factors, we can extrapolate the
overall scenario of thalassemic patients in Bangladesh
using data from West Bengal [20]. The number of
patients suffering from thalassemias (beta major and
HbE beta) with different levels of severity is estimated to
be approximately 60,000–70,000 in Bangladesh [3]. With
the birth rate of 21.6/1000, it could be estimated that
nearly 2500 thalassemia major cases are added every
year in Bangladesh [20]. Due to considerable variation of
thalassemias even within a population, micro mapping is
essential to calculate the actual burden of thalassemia in
Bangladesh. Because of phenomenal success in the control of infec-
tious diseases in Bangladesh, child mortality has declined
by 71% as compared to that observed in the 1990s [14]. Genetic disorders, particularly thalassemias, are therefore
likely to be a major public health concern in Bangladesh
in the coming decades [15]. Background most prevalent in certain malaria prone parts of the
world including Africa, all Mediterranean countries, the
Middle East, the Indian subcontinent and Southeast Asia
[1, 3]. In each year, over 50,000 new patients are born
with a severe form of thalassemia (beta-thalassemia
major and HbE beta thalassemia) worldwide. Due to
high rate of international migration, thalassemias are
spreading to non-endemic parts of the world [2]. In
many Asian countries, the most common form of thalas-
semia results from the coinheritance of beta thalassemia
and HbE. In the eastern parts of Indian subcontinent,
Bangladesh and other Southeast Asian countries, HbE is
the most prevalent hemoglobin variant [4]. Inherited hemoglobin disorders are emerging as a global
public health concern. An estimated 320,000 babies are
born each year with a clinically significant hemoglobin
disorder [1]. Nearly 80% of these births occur in devel-
oping countries. Most conservative estimates suggest
that at least 5.2% of the world population (over 360
million) carry a significant hemoglobin variant [1] and in
excess of 100 million beta thalassemia carriers with a
global frequency of 1.5% [2]. Homozygous or compound
heterozygous states between certain variants can lead to
clinical manifestations of hemoglobinopathies. The inherited beta thalassemias including sickle cell
anemia and hemoglobin E (HbE) disorders are the most
frequent single gene disorders globally [1]. Thalassemia
syndromes are caused by an absence or ineffective
synthesis of beta globin chains. Hemoglobinopathies are South Asia, a hotspot of hemoglobinopathies [2], is
home to 23% of the world’s population (approximately
1.7 billion) [5]. Most information on thalassemia in
South Asia comes from studies conducted in India. Due
to extreme heterogeneity, an uneven frequency of beta
thalassemia heterozygote or carrier in the range of 1 and
10% has been reported throughout different parts of
India [2]. However, the overall prevalence of beta thalas-
semia carriers has been estimated to be between 2.78
and 4% in India [6, 7]. This number translates to Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 Page 2 of 9 Page 2 of 9 based data. According to World Health Organization
(WHO) estimates, approximately 3% of the population
are the carriers of beta-thalassemia and 4% are the car-
riers of hemoglobin E (HbE) in Bangladesh [7]. Background In this comprehensive review,
the objective is to depict the epidemiological aspects of
thalassemias and current management practices in the
country by sharing the experience based on a specialized
thalassemia treatment centre. In addition, we intend to
provide
preventative
strategies
of
thalassemias
from
Bangladesh’s perspective. Patient and clinical set up of TFH A meta-analysis comprising 8505 alleles among the
Indian population has revealed that five mutations
[IVSI-5(G > C), IVSI-1(G > T), 619-bp del, Codon 41/
42(-TCTT) and Codon 8/9(G)] accounts for 90% of all
beta-globin mutation [25]. IVS I-5 (G > C) is the most
prevalent β-thalassemia mutation in South Asia but the
frequency varies ranging from 36.5% in Pakistan, 56.3%
in India and to 64.6% in Sri Lanka [25]. Our study centre is one of the two specialized hospitals
in the country that solely deal with thalassemia patients. TFH is located in Dhaka, the capital city of Bangladesh. This
day-care
service
centre
was
established
by
thalassemia support group and families of the patients. Initially, it was a small discussion group to exchange up-
to-date information on thalassemia management and the
problems
faced
by
thalassemia
patients
and
their
families. The number of patients grew substantially over
next couple of years. The unavailability of iron chelator
medicines and need of a convenient transfusion facility
were the major problems raised by the families. To
address these problems, TFH started its journey in 2008
to provide day-care services including blood transfusion,
expert consultation, medicines and laboratory tests from
a single center. The hospital is currently managed by
two senior hematologists, one transfusion medicine con-
sultant, and a team of 15 doctors, nurses and support
staff. Despite a large number of thalassemic carriers in
Bangladesh, the genetic basis of thalassemia is largely
unknown. Virtually no molecular diagnostic service
centres are available in the country to pinpoint the
mutations in the beta globin gene. To the best of our
knowledge, there are only two reports exist on the
mutation status of thalassemia in Bangladesh. A recent
study (n = 256) showed prevalence of the five most
common mutations including IVSI-5(G > C),
Codon
41/42(-TCTT), Codon 8/9(G) codon 15 (G > A) and
codon 30 (G > C), where IVSI-5 was found to be the
most common in Bangladeshi patients (39.1%) [26]. In another study (n = 16), IVS-I-5 (G > C) accounted
for 56.25% [27]. As expected and discussed earlier, the
mutation profile (five common mutations) of Eastern
India (West Bengal) was found to be similar to that of
Bangladesh, IVS I-5(G > C) being the highest form of In this study, patients attending THF from 1/2009 to
12/2014 were included. Epidemiology Despite the high prevalence of malaria, contrary to the
African region and certain parts of India, sickle cell The information on the prevalence of hemoglobinopa-
thies in Bangladesh is scarce due to lack of population- Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 Page 3 of 9 mutation (71.4%), with Codon 30(G > C) and Codon
15(G > A) the second and third most common alleles [28]. The 619 bp deletion mutation is less frequent in
Bangladesh (0.8%) and Eastern India [25, 26]. mutation (71.4%), with Codon 30(G > C) and Codon
15(G > A) the second and third most common alleles [28]. The 619 bp deletion mutation is less frequent in
Bangladesh (0.8%) and Eastern India [25, 26]. hemoglobin (HbS) is almost non-existent in Bangladesh. Although there has been evidence of a strong association
in geographical distribution between malaria and HbS,
the relationship was found to be strong in only Africa
but not in the Americas or in Asia [21]. In India, HbS
variant is mostly confined to the hilly areas and Western
region
[22]. Due to non-existence of confirmatory
diagnostic test (such as sickle solubility test) in most
diagnostic centres, it appears that some cases of HbS
could be misdiagnosed as HbD beta thalassemia, which
is relatively a common form of hemoglobinopathy in
Bangladesh and India. Mutation profile of thalassemia in Bangladesh Mutation profile of thalassemia in Bangladesh
The spectrum
of
mutations
varies
across
different
geographical regions and cultures. Hence, the regional
mutation profiling is essential to undertake any strat-
egies (e.g. genetic counseling, prenatal diagnosis) to deal
with thalassemias. Different mutations are associated
with different types of thalassemias that influence the se-
verity of the diseases. Mutations in globin genes (α or β)
affect the synthesis of the globin chain that lead to in-
complete erythropoiesis. The diagnosis of alpha thalas-
semia is often difficult and most cases (approximately
90%) remain as carrier among the population of the
Indian Subcontinent. Therefore, alpha thalassemia is
beyond the scope of our present discussion [23]. More
than 400 mutations or alleles have been reported for
beta thalassemia [24]. To portray the overall current scenario of thalassemia
management practice in Bangladesh, the experiences
obtained from Thalassemia Foundation Hospital (TFH)
are presented in this article. Management practice of thalassemia in
Bangladesh Standard thalassemia management comprises of a multi-
disciplinary approach involving an array of specialties
including pediatric hematology, pediatrics, transfusion
medicine, endocrinology, cardiology, dentistry, dieticians,
psychology, psychiatry, social work along with a robust
blood bank system and infrastructure [29]. In developing
countries like Bangladesh, these multidisciplinary expert-
ise and support facilities are not usually available in most
public hospitals and private clinics. In addition, overall
health awareness is very poor among the general popula-
tion in Bangladesh and there is no organized patient
referral system. As a consequence of inadequate access to
healthcare, a significant proportion of the thalassemic
patients might die even without knowing their disease
conditions. There is no national policy or national health
insurance system regarding thalassemia prevention in
Bangladesh. Patient and clinical set up of TFH This hospital-based retrospective
study was ethically approved by the Ethical Review
Committee of Bangladesh University of Health Sciences
(Memo No: BUHS/ERC/16/031). Charts of the patients Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 Page 4 of 9 Page 4 of 9 were reviewed. After registration at the hospital each
patient was provided a unique ID to maintain further
documentation. At first visit to the center, detailed his-
tory, physical examination findings, height and weight,
were recorded. CBC, Hb electrophoresis (preferably at
the time of diagnosis and prior to transfusion), basic
metabolic panel, liver functions tests, and baseline iron
status were obtained. At initial visit, patients were
assessed for the transfusion requirement. Patients were
observed for 4 weeks and were followed up for clinical
symptoms and Hb. Patients stable after this period were
further monitored to determine the steady state Hb and
correlation of Hb with clinical symptoms. This was to
categorize the patients clinically into thalassemia inter-
media and to determine transfusion trigger. Patients
were followed up every 4–6 weeks for quality of life
(QOL), worsening organomegaly and growth failure. Transfusion dependent patients were monitored for iron
loading and medication side effects. Hydroxyurea was
used
in
thalassemia
intermedia
patients
and
were
followed up for QOL and Hb increment. generally include HbE beta thalassemia and beta thal-
assemia intermedia that do not require regular blood
transfusions for survival [30]. However, in TFH, we
found some diagnosed carrier patients admitted as
TDT (10 cases) and NTDT (17 cases). Infection and
iron deficiency, particularly in reproductive age females,
could compound the pre-existing anemia although these
patients are not actually transfusion dependent. This
could be due to misdiagnosis and/or lack of awareness
among the clinicians in Bangladesh. Thalassemia intermedia (TI) is defined as a group of pa-
tients with beta thalassemia characterized by diverse clin-
ical severity between transfusion dependent thalassemia
major and mild symptoms of beta thalassemia trait. Most
TI patients are homozygous and compound heterozygous
for beta thalassemia [31]. In Southeast Asia including the
Indian subcontinent, the most common form of severe
thalassemias results from the coinheritance of HbE and
beta trait. Based on clinical severity, HbE beta thalassemia
could be classified into three categories: mild (15% cases),
moderately severe (majority of HbE beta thalassemia
cases) and severe. Up to 50% of all patients with HbE beta
thalassemia represent clinical manifestations similar to
those of beta thalassemia major [32]. Patient and clinical set up of TFH p
Over a 5-year period (2009–2014), a total of 1594
thalassemia
patients
were
served
by
TFH
out
of
which 1178 complete cases were analyzed with a male
to female ratio of 1.26. All cases of thalassemias were
diagnosed using conventional electrophoresis method. Approximately 77.3% of the patients were diagnosed
as HbE beta thalassemia, while nearly 15% were beta
thalassemia
major. About
91%
patients
(n = 971)
required
blood
transfusion,
where
approximately
66.9%
of them were
transfusion-dependent
thalas-
semia (TDT) patients and 24.3% were non-transfusion
dependent
thalassemia
(NTDT)
(Table
1). About
41.1% of TDT patients required blood transfusion
every 2–4 weeks. Due to incomplete medical record,
the transfusion history was missing for 115 diagnosed
cases (approximately 9.7% of all cases). Due to extensive clinical diversity, the management of
NTDT is often challenging. Diagnosis and management
of NTDT mainly depend on clinical observations. In our
study, over 62% of HbE beta thalassemia patients were
treated as TDT while about 28% were NTDT (Table 1). This
unexpected
higher
proportion
of
transfusion
dependent HbE beta thalassemia in Bangladesh might
result from inaccurate or misdiagnosis of the severity of
different clinical manifestations of thalassemia patients. It could also be attributable to using Hb level to deter-
mine need for transfusion in HbE beta patients as op-
posed to using other criteria including growth failure,
delayed puberty, splenomegaly, tendency to thrombosis
and pulmonary hypertension [33]. A complete mutation
profile (DNA testing) prior to initiation of treatment is
helpful to determine the prognosis, appropriate therapy
and family counseling [29]. NTDT, non-transfusion dependent thalassemia; TDT, transfusion dependent thalassemia Transfusion practice Transfusion practice Thalassemia carriers are healthy and do not require
blood transfusion. Non-transfusion dependent thalassemias Table 1 Pattern of thalassemia and transfusion practice in Bangladesh
Diseases types
n (%)
Median age
(year) at diagnosis
Transfusion status #/n (%)
TDT
NTDT
Not required
Hb-E-beta thalassemia
910 (77.25)
3.5
522/840 (62.14)
238/840 (28.33)
80/840 (9.52)
Beta thalassemia major
173 (14.69)
0.58
172/173 (99.42)
1/173 (0.58)
0/173 (0)
Beta thalassemia trait
64 (5.43)
27.5
8/26 (30.77)
14/26 (53.85)
4/26 (15.38)
Hb E disease
12 (1.02)
9
3/11 (27.27)
3/11 (27.27)
5/11 (45.45)
Hb-E trait
14 (1.19)
26
2/8 (25)
3/8 (37.50)
3/8 (37.50)
Others (H, Punjab D etc.)
5 (0.42)
4
5/5 (100)
0/5 (0)
0/5 (0)
Total
1178
712/1063 (66.98)
259/1063 (24.36)
72/1063 (8.66)
NTDT, non-transfusion dependent thalassemia; TDT, transfusion dependent thalassemia Table 1 Pattern of thalassemia and transfusion practice in Bangladesh Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 Page 5 of 9 Increased awareness among clinicians is a prerequisite
for proper diagnosis and management of NTDT. Several
studies have suggested the limitation of Hb level as a
clinical
decision
indicator
for
starting
transfusion
dependent management [30] since there were only
minor differences in Hb levels (1.8–2.6 g/dl) between
the mildest and most severe forms of HbE beta thalas-
semia. In addition, some children with HbE beta thalas-
semia were found to adapt to lower levels of Hb and
managed almost normal life without transfusion [34, 35]. In one study conducted in Sri Lanka, approximately 42%
(37/84 cases) of patients with HbE beta thalassemia
could be reversed from TDT to NTDT without any
deleterious medical conditions, suggesting that many of
these patients actually received unnecessary regular
blood transfusion therapy [36]. Patients with NTDT
sometimes could suffer from severe anemia due to acute
infection, therefore, transfusion therapy is not recom-
mended immediately after diagnosis of NTDT [32]. Despite this fact, patients are not dependent on regular
transfusions for survival although transfusion therapy
may provide significant clinical benefits for some pa-
tients if administered properly [30]. positive cases of HCV among multi-transfused thalas-
semia patients [28]. Treatment cost of thalassemia in Bangladesh g
The cost of treatment varies according to age, body
weight and severity of the disease. The most conserva-
tive direct medical cost ranges from BDT 127,000 (USD
1632; USD 1 = BDT 78) to BDT 309,000 (USD 3960) per
year (Table 2). There is neither a national insurance
system nor subsidized or free treatment from the gov-
ernment health facilities. It is expected that patients
must pay for their treatment and it is difficult for most
of the families to afford proper treatment. Over 72% of
the patients’ (n = 448) monthly household income was
between BDT 10,000 (USD128) to BDT 20,000 (USD
256), suggesting a huge economic burden that could
render seeking treatment for most thalassemia patients
unviable in Bangladesh. Apart from patho-physiological, psychological and the
financial burden, the regular arrangement of safe blood is
one of the biggest challenges faced by transfusion-
dependent families in developing countries. In Bangladesh,
85% of collected blood is contributed by patient’s relatives
and friends, while the rest (15%) is donated by voluntary
blood donors [37]. Taking this into consideration, before
starting transfusion therapy, accurate diagnosis should be
a mandatory part of the thalassemia management practice
in Bangladesh. Future directions and recommendations Thalassemias impose a significant burden on healthcare
systems in endemic regions since the lifetime manage-
ment cost of thalassemia is beyond the capacity of
resource-constrained countries. It is estimated that only
12% of patients with transfusion-dependent thalassemia
are properly transfused and of those less than 40% have
access to adequate iron chelation [1]. Iron chelation and hydroxyurea therapy In our study, approximately 43% of the patients (n = 972)
with multiple blood transfusions were treated with iron
chelators
to
remove
excess
iron
from
the
body. Deferiprone was the most commonly used iron chelator
(n = 481) followed by Deferasirox (n = 199) and Desferal
(n = 91). Hydroxyurea therapy was given to nearly 43% of
the
patients
(n = 972)
who
underwent
transfusions
regularly or occasionally to increase foetal hemoglobin
and reduce ineffective erythropoiesis. Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 Infection TDT thalassemia patients are at risk of developing post-
transfusion hepatitis. Among these infections, hepatitis B
and C are the most common. Due to lack of effective
vaccines against HCV and inadequate infection control
strategies, HCV is considered as major public problem
in low to middle-income countries [38]. Approximately
180.5 million people are infected by HCV in the world,
of which 54.4 million is in South Asia [39]. A number of
studies have reported the higher prevalence of HCV
among multi-transfused thalassemia patients, ranging
from 3 to 67.3% [40–43]. Increased risk of HCV infec-
tion in β-thalassemia patients is mainly associated with
median age, duration, and mean amount of blood trans-
fused. No HIV cases were detected in TFH. In case of
HBV, 6 cases were positive among 523 tested cases who
had blood transfusion. In the present study, 28.3% of the
tested cases (n = 247) who underwent multiple transfu-
sions were found to be HCV positive. Another previous
study conducted in Bangladesh also observed higher Due to increased life expectancy and slowing popula-
tion growth, Bangladesh is now experiencing the double
burden
of
communicable
and
noncommunicable
diseases (NCDs) [9]. Currently, in Bangladesh, NCDs
account for 59% of total deaths (WHO), which in turn,
has created a strain on the existing healthcare system in
country. The government of Bangladesh spends only US
$26.60 per capita for healthcare services [44]. The man-
agement of the disease is multifaceted and expensive. There is no cure for thalassemia except for allogeneic
BMT in a select group of patients which again is a very
expensive treatment option. The management of this
disease is also very costly. As mentioned earlier, an
average Bangladeshi family has to spend more than their
monthly household income for a thalassemia major
patient. However, the prevention of thalassemia is cost Hossain et al. Prenatal screening
A
d g
A secondary prevention strategy emphasizes prenatal
diagnosis followed by genetic counselling for the termin-
ation of pregnancy. The acceptability of the prenatal
diagnosis
and
selective
termination/abortion
of
an
affected foetus is determined by many factors including
religious, social and cultural backgrounds, personal
experiences and beliefs. Therefore, ethical guidelines
concerning genetic counseling, carrier screening and
prenatal diagnosis need to be evaluated on the context
of each society or country. Bangladesh is a predomin-
antly Muslim country and social practices are heavily in-
fluenced by the religious practices. From the perspective
of Islamic jurisprudence, it is permissible to perform
abortion to protect mother’s life or health, or because of
foetal anomaly which is incompatible with life [49]. A
study conducted in the highly conservative Muslim
society of Pakistan has shown that selective termination
is accepted by affected parents irrespective of religious
and social groups after genetic counseling [50]. Due to
the extreme sensitivity of abortion from an Islamic view-
point, mistakes are not permissible in the diagnosis of
foetal anomalies [49]. Infection Orphanet Journal of Rare Diseases (2017) 12:93 Page 6 of 9 Table 2 Conservative estimate of treatment cost at Thalassemia Foundation Hospital, Bangladesh
Requirements
Cost (USD)
1–10 years
11–20 years
21–30 years
Blood Transfusion plus filter/month
32 (1 unit)
65 (2 units)
96 (3 units)
Iron chelation (Desferrioxamine/deferasirox)
65 (25 vials)
130 (50 vials)
195 (75 vials)
Hospital care 1 day/month
26
26
26
Lab tests/month
13
13
13
Total cost/month
136
234
330
Total cost/year
1632
2808
3960 Table 2 Conservative estimate of treatment cost at Thalassemia Foundation Hospital, Bangladesh effective; at least four times less expensive than treating
thalassemia based on a study conducted in Israel [45]. Prevention is therefore likely to be the most viable strat-
egy to reduce the burden of the thalassemia patients on
families and to manage a sustainable healthcare system. approach since the vast majority of the women, particu-
larly in resource-limited rural areas, cannot be screened. Under these circumstances, selective screening approach
within the families suffering from thalassemia could be a
viable approach in Bangladesh. In the study, anecdotal
data (n = 605) on the family history of thalassemia sug-
gest that 20% had another thalassemic siblings while 3%
had two or more siblings with thalassemia. The majority
of thalassemic couples in Bangladesh are identified
retrospectively after diagnosis of one or more affected
children: this could be used as a proxy indicator to test
extended family to craft an effective carrier identification
approach in Bangladesh. Given appropriate public health
dissemination messages to affected and extended fam-
ilies, this could raise awareness of genetic susceptibility
to thalassemia. In Sardinia, this approach was applied to
only 15% of the adult population, which led to the detec-
tion of 90% of expected at-risk couples [47]. Pre-marital screening g
A primary preventive program is based on the carrier
[heterozygous] detection and counselling to discourage
marriage between carriers. Overall, premarital screening
for thalassemia and other preventable genetic diseases
are widespread in many parts of the world [46]. The
success of mandatory premarital screening with genetic
counseling was only effective in reducing beta thalas-
semia births in some Middle Eastern countries (Iran,
Turkey) because of widespread awareness, screening
timing and access to prenatal diagnosis (PND) and the
option of therapeutic abortion [47]. In addition, Taiwan
adopted a national screening program in 1993 to man-
age the spread of thalassemia which enjoyed consider-
able success, with less than three per year of thalassemia
births in last 10 years [48]. Prevention via pre-marital
and genetic screening is arguably the best approach to
prevent thalassemias considering socio-religious issues,
among other factors. However, the success of mandatory
premarital screening with genetic counseling was only
effective in reducing beta thalassemia births in some
Middle Eastern countries (Iran, Turkey) because of
widespread awareness, screening timing and access to
prenatal diagnosis (PND), and the option of therapeutic
abortion [47]. In conservative societies, marriage is a
very complex social phenomenon where couples are
usually selected based on strong personal preference as
well as traditional reasons. Depending on the thalas-
semia carrier status, if a planned marriage is called off, it
may cause social embarrassment or stigmatization to the
young couples and their families. Funding
Th
d This study was partially supported by Biomedical Research Foundation,
Bangladesh. 5. Regional and international partnership and
collaboration are necessary for the control and
management of thalassemia in developing
countries like Bangladesh. This study was partially supported by Biomedical Research Foundation,
Bangladesh. Abbreviations
b
l b HbE: Hemoglobin E; HBV: Hepatitis B virus; HCV: Hepatitis C virus; NCD: No
communicable disease; NTDT: Non-transfusion dependent thalassemia;
TDT: Transfusion dependent thalassemia; TFH: Thalassemia Foundation
Hospital 3. Availability of genetic testing can prevent further
birth of affected children in the family and can
encourage for prenatal screening. Target screening approaches Due to inadequate healthcare access as well as infra-
structure and financial constraints, the antenatal screen-
ing in pregnant women is not a practically feasible Page 7 of 9 Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 Newborn screening (NBS) tests are practiced in devel-
oped countries using advanced molecular techniques to
facilitate the early diagnosis of haemoglobinopathies for
the prevention of complications and management [51]. Due to resource limitation in developing countries like
Bangladesh, the application of NBS appears to be
unrealistic. included in the development of prevention policies
(such as prenatal screening followed by abortion)
on genetic disorders. 7. Electronic health information exchange (such as
Apps) could be an important tool to ensure proper
care of thalassemia patients. It is needed to focus on
the understanding of the patient’s attribute to tailor
intervention by leveraging information technology
and patient-level data. 7. Electronic health information exchange (such as
Apps) could be an important tool to ensure proper
care of thalassemia patients. It is needed to focus on
the understanding of the patient’s attribute to tailor
intervention by leveraging information technology
and patient-level data. The prime objective of a thalassemia prevention
program is to educate the public as well as health
professionals about the concept and consequence of
genetic disorders. In a predominantly illiterate soci-
ety/community, a special strategy is required to edu-
cate the public. General observation shows that health
professionals are a vital source of information for a
thalassemia
affected
family. To
make
an
effective
public awareness strategy, priority should be given to
educate
healthcare
professionals
first. Very
little
genetics is taught in undergraduate medical colleges
in Bangladesh. At the postgraduate level, genetics
tends to be a neglected specialty. Because of the
young age structure of the population, thalassemia
awareness focused on schools, colleges and univer-
sities had a significant impact in most developed
societies and it would have the same impact in devel-
oping countries. It is essential to replace misunder-
standings with correct information about the cause of
genetic disease and resources available for its diagno-
sis, treatment and prevention. In this context, mass
media such as television and newspaper could be vital
tools for public awareness. 8. Private-public partnership must be promoted to
tackle thalassemia in developing countries like
Bangladesh. 8. Private-public partnership must be promoted to
tackle thalassemia in developing countries like
Bangladesh. Acknowledgements g
We thank Fahmid Khondaker, Australia, and Nova Ahmed, Biomedical
Research Foundation, Bangladesh for proofreading our manuscript. g
We thank Fahmid Khondaker, Australia, and Nova Ahmed, Biomedical
Research Foundation, Bangladesh for proofreading our manuscript. g
We thank Fahmid Khondaker, Australia, and Nova Ahmed, Biomedical
Research Foundation, Bangladesh for proofreading our manuscript. 4. Prioritizing thalassemia awareness and access
programs for the targeted population should be
designed through innovative approaches. Conclusion The present study depicts the overall treatment strategies
prevailing in Bangladesh. We found a significant propor-
tion of beta thalassemia carriers receiving transfusion. As
mentioned previously, it could be due to misdiagnosis
(e.g. concurrent iron/ vitamin deficiency) or a higher tar-
get Hb level for the patients due to lack of awareness
among the practicing physicians. Beta thalassemia carriers
can have mild anemia with Hb level ranging from 9 to
12 g/dL which does not warrant transfusion to normalize
the Hb level. Individual response and adaptation to
anemia may also play a role in selecting patients for trans-
fusion. On the other hand, in case of HbE beta thalas-
semia, the most crucial issue is to determine transfusion
dependence. Other neighboring countries like Sri Lanka
may serve as a model in re-evaluating the transfusion
practices in Bangladesh, as regards to thalassemia [52]. Modification of the existing candidate selection criteria
for transfusion requirement, which is mostly based on Hb
level currently practice in Bangladesh, will play a signifi-
cant role in screening out patients that might benefit from
other essential yet often neglected therapeutic interven-
tions. Further investigations are necessary to understand
the epidemiology, mutation spectrum, clinical course and
treatment outcomes in this thalassemia prone country,
which is undergoing demographic transition. Listed below are some specific recommendations in
the context of Bangladesh: 1. Virtually, nothing is known on various aspects
including true burden, genetic spectrum, clinical
outcome, morbidity and mortality of thalassemia
in Bangladesh. Hence, research is the first and
foremost priority to establish thalassemia as one of
the major public health problems in Bangladesh. 2. Establish improved diagnostics and treatment
facilities for thalassemias preferably in a one
stop center. Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 Ethics approval and consent to participate Ethical approval for this retrospective study was obtained from the Ethics
Committee of the Bangladesh University of Health Sciences (Memo No:
BUHS/ERC/16/031). 18. Saha N. Blood genetic markers in Bengali Muslims of Bangladesh. Hum
Hered. 1987;37(2):86–93. 19. Eaaswarkhanth M, Dubey B, Meganathan PR, Ravesh Z, Khan FA, Singh
L, et al. Diverse genetic origin of Indian Muslims: evidence from
autosomal STR loci. J Hum Genet. 2009;54(6):340–8. Available from:
doi:10.1038/jhg.2009.38. Availability of data and materials The datasets analysed during the current study are not publicly available but
may be available from the corresponding author on reasonable request
following an application to and with approval from the local ethics
committee. 6. Given the conservative religious society in
Bangladesh, respected religious scholars should be Page 8 of 9 Page 8 of 9 Page 8 of 9 Page 8 of 9 Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations. 20. Mandal PK, Maji SK, Dolai TK. Present scenario of hemoglobinopathies in
West Bengal, India: An analysis of a large population. Int J Med Public Heal. 2014;4(4):496-99. Author details
1 1Biomedical Research Foundation, House #7, Apartment# 1A, Road# 1/B,
Banani, Chairman Bari, Dhaka-1213, Bangladesh. 2Faculty of Basic Sciences,
Bangladesh University of Health Sciences, Dhaka, Bangladesh. 3School of
Environmental Science and Management, Independent University, Dhaka,
Bangladesh. 4Thalassemia Foundation Hospital, Dhaka, Bangladesh. 5Trinity
College, Dublin, Ireland. 6Department of Economics & Business, Moravian
College, Bethlehem, USA. 7Saint Michael’s Medical Center, Newark, NJ, USA. 21. Piel FB, Patil AP, Howes RE, Nyangiri OA, Gething PW, Williams TN, et al. Global distribution of the sickle cell gene and geographical confirmation of
the malaria hypothesis. Nat Commun. 2010;1(104). Available from doi: 10. 1038/ncomms1104. 22. Urade BP. Haemoglobin S and βThal: their distribution in Maharashtra, India. Int J Biomed Sci. 2013;9(2):75–81. 23. Panja A, Ghosh TK, Basu A. Genetics of thalassemia in Indian population. J Community Nutr Heal. 2012;1(1):39–46. Received: 21 February 2017 Accepted: 27 April 2017 24. HbVar. Database of human hemoglobin variants and thalassemias. Available
from: http://globin.cse.psu.edu/globin/hbvar/. 25. Black ML, Sinha S, Agarwal S, Colah R, Das R, Bellgard M, et al. A descriptive
profile of beta-thalassaemia mutations in India, Pakistan and Sri Lanka. J Community Genet. 2010;1(3):149–57. Consent for publication Consent for publication
Not applicable. Not applicable. 17. Shannon KL, Ahmed S, Rahman H, Prue CS, Khyang J, Ram M, et al. Hemoglobin E and glucose-6-phosphate dehydrogenase deficiency and
Plasmodium falciparum malaria in the Chittagong Hill Districts of
Bangladesh. Am J Trop Med Hyg. 2015;93(2):281–6. Authors’ contributions 13. Thurlow RA, Winichagoon P, Green T, Wasantwisut E, Pongcharoen T, Bailey
KB, et al. Only a small proportion of anemia in northeast Thai schoolchildren
is associated with iron deficiency. Am J Clin Nutr. 2005;82(2):380–7. MSH, MAR (Rahim), MM, ER conceived the study. MSH, ER, MAR (Rahim)
carried out analysis, interpretation of data and contributed in writing
manuscript. NN, SI acquisition of data, SH, MA, MAR (Razzaque), RA, HR, SA,
TAS, MM contributed in manuscript writing. MSH drafted initial manuscript. All authors read and approved final manuscript. 14. Worldbank. Country and lending groups. Worldbank. 2013. p. 1. Available
from: http://data.worldbank.org/about/country-classifications/country-and-
lending-groups#Lower_middle_income. 15. Weatherall DJ. The challenge of haemoglobinopathies in resource-poor
countries. Br J Haematol. 2011;154:736–44. References
d ll 1. Modell B, Darlison M. Global epidemiology of haemoglobin disorders and
derived service indicators. Bull World Health Organ. 2008;86:480–7. 1. Modell B, Darlison M. Global epidemiology of haemoglobin disorders and
derived service indicators. Bull World Health Organ. 2008;86:480–7. 26. Chatterjee T, Chakravarty A, Chakravarty S, Chowdhury MA, Sultana R. Mutation spectrum of β -thalassemia and other hemoglobinopathies in
Chittagong, Southeast Bangladesh. Hemoglobin. 2015;39(6):389–92. Available from: http://www.tandfonline.com/doi/full/10.3109/03630269.2015. 1078810. 2. Colah R, Gorakshakar A, Nadkarni A. Global burden, distribution and
prevention of β-thalassemias and hemoglobin E disorders. Expert Rev
Hematol. 2010;3(1):103–17. Available from: http://www.ncbi.nlm.nih.gov/
pubmed/21082937. 2. Colah R, Gorakshakar A, Nadkarni A. Global burden, distribution and
prevention of β-thalassemias and hemoglobin E disorders. Expert Rev
Hematol. 2010;3(1):103–17. Available from: http://www.ncbi.nlm.nih.gov/
pubmed/21082937. 3. Weatherall DJ. The inherited diseases of hemoglobin are an emerging
global health burden. Blood. 2010;115(22):4331–6. 3. Weatherall DJ. The inherited diseases of hemoglobin are an emerging
global health burden. Blood. 2010;115(22):4331–6. 27. Ibn Ayub M, Moosa MM, Sarwardi G, Khan W, Khan H, Yeasmin S. Mutation
analysis of the HBB gene in selected Bangladeshi beta-thalassemic individuals:
presence of rare mutations. Genet Test Mol Biomarkers. 2010;14(3):299–302. Available from: http://www.ncbi.nlm.nih.gov/pubmed/20406103. 4. Olivieri NF, Pakbaz Z, Vichinsky E, et al. Hb E/beta-thalassaemia: a common
& clinically diverse disorder. Indian J Med Res. 2011;134(4):522. 5. Central Intelligence Agency. The World Factbook 2016. Washington, DC:
Central Intelligence Agency; 2016. Available from: https://www.cia.gov/
library/publications/resources/the-world-factbook/geos/gt.html. 5. Central Intelligence Agency. The World Factbook 2016. Washington, DC:
Central Intelligence Agency; 2016. Available from: https://www.cia.gov/
library/publications/resources/the-world-factbook/geos/gt.html. 28. Verma IC, Saxena R, Kohli S. Past, present & future scenario of thalassaemic
care & control in India. Indian J Med Res. 2011;134:507–21. 29. Sayani F, Warner M, Wu J, Wong-Rieger D, Humphreys K, Odame I. Guidelines for the clinical care of patients with thalassemia in Canada. Available from: http://www.thalassemia.ca/wpcontent/uploads/Thalassemia-
Guidelines_LR.pdf. 6. Mohanty D, Colah RB, Gorakshakar AC, Patel RZ, Master DC, Mahanta J, et al. Prevalence of beta-thalassemia and other haemoglobinopathies in six cities
in India: a multicentre study. J Community Genet. 2013;4(1):33–42. y
y
7. Organization WH, et al. Management of haemoglobin disorders: report of a
joint WHO-TIF meeting, Nicosia, Cyprus, 16-18 November 2007. 2008. 30. Taher AT, Radwan A, Viprakasit V. When to consider transfusion therapy for
patients with non-transfusion-dependent thalassaemia. Vox Sang. 2015;108(1):1–10. 8. Ansari SH, Shamsi TS, Ashraf M, Farzana T, Bohray M, Perveen K, et al. Molecular epidemiology of beta-thalassemia in Pakistan: far reaching
implications. Competing interests 16. Khan WA, Banu B, Amin SK, Selimuzzaman M, Rahman M, Hossain B, et al. Prevalence of beta thalassemia trait and Hb E trait in Bangladeshi school
children and health burden of thalassemia in our population. DS HJ. 2005;21(1):1–7. The authors declare that they have no competing interests. References
d ll Global distribution and prevalence of hepatitis C virus genotypes. Hepatology. 2015;61(1):77–87. 40. Ali I, Siddique L, Rehman LU, Khan NU, Iqbal A, Munir I, et al. Prevalence of
HCV among the high risk groups in Khyber Pakhtunkhwa. Virol J. 2011;8(1):296. Available from: http://www.pubmedcentral.nih.gov/
articlerender.fcgi?artid=3121710&tool=pmcentrez&rendertype=abstract. 40. Ali I, Siddique L, Rehman LU, Khan NU, Iqbal A, Munir I, et al. Prevalence of
HCV among the high risk groups in Khyber Pakhtunkhwa. Virol J. 2011;8(1):296. Available from: http://www.pubmedcentral.nih.gov/
articlerender.fcgi?artid=3121710&tool=pmcentrez&rendertype=abstract. 41. Khan NU, Ali I, Ahmad NU, Iqbal A, Rehman LU, Munir I, et al. Prevalence of
active HCV infection among the blood donors of Khyber Pakhtunkwa and
FATA region of Pakistan and evaluation of the screening tests for anti-HCV. Virol J. 2011;8(1):154. Available from: http://www.pubmedcentral.nih.gov/
articlerender.fcgi?artid=3080828&tool=pmcentrez&rendertype=abstract. 42. López L, López P, Arago A, Rodríguez I, López J, Lima E, et al. Risk factors for
hepatitis B and C in multi-transfused patients in Uruguay. J Clin Virol. 2005;
34 Suppl 2:S69–74. Available from: https://www.scopus.com/inward/record. uri?eid=2-s2.0-32044448148&partnerID=40&md5=
9b8b441cb1ee95bcd44c089bf913ab4b. 43. Vidja PJ, Vachhani JH, Sheikh SS, Santwani PM. Blood transfusion
transmitted infections in multiple blood transfused patients of beta
thalassaemia. Indian J Hematol Blood Transfus. 2011;27(2):65–9. 43. Vidja PJ, Vachhani JH, Sheikh SS, Santwani PM. Blood transfusion
transmitted infections in multiple blood transfused patients of beta
thalassaemia. Indian J Hematol Blood Transfus. 2011;27(2):65–9. 44. Ahmed SM, Alam BB, Anwar I, Begum T, Khan JA, Nababan H, et al. Bangladesh: Health System Review. Health systems in transition. 2015;5. Available from: http://www.wpro.who.int/asia_pacific_observatory/hits/
series/bgd_health_system_review.pdf 44. Ahmed SM, Alam BB, Anwar I, Begum T, Khan JA, Nababan H, et al. Bangladesh: Health System Review. Health systems in transition. 2015;5. Available from: http://www.wpro.who.int/asia_pacific_observatory/hits/
series/bgd_health_system_review.pdf 45. Koren A, Profeta L, Zalman L, Palmor H, Levin C, Zamir RB, et al. Prevention
of beta Thalassemia in Northern Israel - a cost-benefit analysis. Mediterr J
Hematol Infect Dis. 2014;6(1):e2014012. Available from: http://www.ncbi.nlm. nih.gov/pmc/articles/PMC3965716/pdf/mjhid-6-1-e2014012.pdf. 45. Koren A, Profeta L, Zalman L, Palmor H, Levin C, Zamir RB, et al. Prevention
of beta Thalassemia in Northern Israel - a cost-benefit analysis. Mediterr J
Hematol Infect Dis. 2014;6(1):e2014012. Available from: http://www.ncbi.nlm. nih.gov/pmc/articles/PMC3965716/pdf/mjhid-6-1-e2014012.pdf. 46. Alswaidi FM, O’Brien SJ. Premarital screening programmes for
haemoglobinopathies, HIV and hepatitis viruses: review and factors affecting
their success. J Med Screen. 2009;16(1):22–8. Available from: https://www. ncbi.nlm.nih.gov/pubmed/19349527. 47. Saffi M, Howard N. Exploring the effectiveness of mandatory premarital
screening and genetic counselling programmes for β-thalassaemia in the
Middle East: a scoping review. Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 References
d ll Indian J Hum Genet. 2012;18(2):193. 31. Musallam KM, Taher AT, Rachmilewitz EA. β-thalassemia intermedia: a
clinical perspective. Cold Spring Harb Perspect Med. 2012;2(7): a013482. 9. Islam A, Biswas T. Chronic non-communicable diseases and the healthcare
system in Bangladesh: current status and way forward. Chronic Dis Int. 2014;1(2):6. 32. Viprakasit V, Tyan P, Rodmai S, Taher AT. Identification and key management of
non-transfusion-dependent thalassaemia patients: not a rare but potentially
under-recognised condition. Orphanet J Rare Dis. 2014;9(1):131. 10. Rahman S, Ahmed T, Rahman AS, Alam N, Ahmed AMS, Ireen S, et al. Determinants of iron status and Hb in the Bangladesh population: the role
of groundwater iron. Public Health Nutr. 2016;19(10):1862–74. 33. Fucharoen S, Weatherall DJ. The hemoglobin E thalassemias. Cold Spring
Harb Perspect Med. 2012;2(8):a011734. 34. Allen A, Fisher C, Premawardhena A, Peto T, Allen S, Arambepola M, et al. Adaptation to anemia in hemoglobin E-beta thalassemia. Blood. 2010;116(24):5368–70. 11. Merrill RD, Ahmed Shamim A, Ali H, Labrique AB, Schulze K, Christian P,
et al. High prevalence of anemia with lack of iron deficiency among
women in rural Bangladesh: a role for thalassemia and iron in groundwater. Asia Pac J Clin Nutr. 2012;21(3):416. 35. O’Donnell A, Premawardhena A, Arambepola M, Allen SJ, Peto TEA, Fisher
CA, et al. Age-related changes in adaptation to severe anemia in childhood
in developing countries. Proc Natl Acad Sci U S A. 2007;104(22):9440–4. Available from: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=
1890513&tool=pmcentrez&rendertype=abstract. 12. Karakochuk CD, Whitfield KC, Barr SI, Lamers Y, Devlin AM, Vercauteren SM,
et al. Genetic hemoglobin disorders rather than iron deficiency are a major
predictor of hemoglobin concentration in women of reproductive age in
rural Prey Veng, Cambodia. J Nutr. 2015;145(1):134–42. Page 9 of 9 Hossain et al. Orphanet Journal of Rare Diseases (2017) 12:93 36. Premawardhena A, De Silver S, Arambepola M, Olivieri NF, Vichinsky EP,
Merson L, et al. Hemoglobin E-beta-thalassemia: progress report from the
International Study Group. Ann N Y Acad Sci. 2005;1054:33–9. Available
from: http://www.ncbi.nlm.nih.gov/pubmed/16339649. 37. WHO. Situation assessment of public and private blood centres in
Bangladesh. 2012. Available from: http://apps.who.int/bloodsafety/
transfusion_services/Bangladesh_
SituationAssessmentPublicPrivateBloodCentres.pdf. 38. Papatheodoridis G, Hatzakis A. Public health issues of hepatitis C virus
infection. Best Pract Res Clin Gastroenterol. 2012;26:371–80. 38. Papatheodoridis G, Hatzakis A. Public health issues of hepatitis C virus
infection. Best Pract Res Clin Gastroenterol. 2012;26:371–80. 39. Messina JP, Humphreys I, Flaxman A, Brown A, Cooke GS, Pybus OG, et al. 50.
Ahmed S, Saleem M, Sultana N, Raashid Y, Waqar A, Anwar M, et al. Prenatal
diagnosis of beta-thalassaemia in Pakistan: experience in a Muslim country.
Prenat Diagn. 2000;20(5):378–83. References
d ll Public Health Genomics. 2015;18(4):193–203. 48. Peng CT, Liu SC, Peng YC, Lin TH, Wang SJ, Le CY, et al. Distribution of
thalassemias and associated hemoglobinopathies identified by prenatal
diagnosis in Taiwan. Blood Cells Mol Dis. 2013;51(3):138–41. 48. Peng CT, Liu SC, Peng YC, Lin TH, Wang SJ, Le CY, et al. Distribution of
thalassemias and associated hemoglobinopathies identified by prenatal
diagnosis in Taiwan. Blood Cells Mol Dis. 2013;51(3):138–41. 49. Al-Matary A, Ali J. Controversies and considerations regarding the
termination of pregnancy for foetal anomalies in Islam. BMC Med Ethics. 2014;15(1):1. 49. Al-Matary A, Ali J. Controversies and considerations regarding the
termination of pregnancy for foetal anomalies in Islam. BMC Med Ethics. 2014;15(1):1. 50. Ahmed S, Saleem M, Sultana N, Raashid Y, Waqar A, Anwar M, et al. Prenatal
diagnosis of beta-thalassaemia in Pakistan: experience in a Muslim country. Prenat Diagn. 2000;20(5):378–83. 51. Hoppe CC. Prenatal and newborn screening for hemoglobinopathies. Int J Lab Hematol. 2013;35:297–305. 52. Olivieri NF, Muraca GM, O’Donnell A, Premawardhena A, Fisher C, Weatherall
DJ. Studies in haemoglobin E beta-thalassaemia. In: British journal of
haematology. 2008. p. 388–97. Submit your next manuscript to BioMed Central
and we will help you at every step: Submit your next manuscript to BioMed Central
and we will help you at every step: • We accept pre-submission inquiries
• Our selector tool helps you to find the most relevant journal
• We provide round the clock customer support
• Convenient online submission
• Thorough peer review
• Inclusion in PubMed and all major indexing services
• Maximum visibility for your research
Submit your manuscript at
www.biomedcentral.com/submit
Submit your next manuscript to BioMed Central
and we will help you at every step:
|
https://openalex.org/W247759585
|
https://vsp.spr-journal.ru/jour/article/download/457/362
|
Russian
| null |
THE METHOD OF PNEUMATIC IMITATION OF WEIGHT-BEARING IN CHILDREN WITH SHIN FRACTURES
|
Voprosy sovremennoj pediatrii
| 2,012
|
cc-by
| 5,206
|
ВВЕДЕНИЕ гиподинамии. Использование этих методов при перело-
мах длинных костей, направленное сначала на сращение
и лишь затем на восстановление функций конечности,
затягивает сроки стационарного лечения, на длительный
срок снижает качество жизни маленького пациента и его
родителей, увеличивает время реабилитации до полного
выздоровления ребенка [3–5]. Разработка и внедрение
в клиническую практику систем внешней и внутренней
фиксации для стабилизации костных отломков позволили
значительно сократить сроки лечения больных с травмами
опорно-двигательного аппарата, быстрее восстанавли-
вать функциональность конечности. Однако конструкции
внешней фиксации громоздки, требуют постоянного ухода,
и нередко их применение осложняется воспалением окру-
жающих тканей и/или прорезыванием спиц. Открытые
оперативные методы лечения позволяют добиться проч-
ной и точной фиксации отломков и приводят к дополни-
тельному повреждению мягких тканей, осложнениям,
косметическим дефектам [6, 7]. В настоящее время показатели детского травматизма
превышают таковые у взрослых пациентов. Из общего
числа повреждений большая часть приходится на трав-
мы опорно-двигательного аппарата. Переломы костей
голени у детей являются наиболее частыми повреждени-
ями скелета и составляют от 15 до 20% всех переломов
опорно-двигательной системы [1, 2], что совпадает с дан-
ными нашего института в период с 2007 по 2011 гг. Еще недавно в лечении переломов костей голени
у детей превалировали консервативные методы. Однако
скелетное вытяжение и гипсовая иммобилизация часто
не позволяют добиться оптимальной репозиции и стаби-
лизации отломков, на длительное время происходит обез-
движивание поврежденной конечности и самого пациента. Консервативные методы лечения способствуют развитию
функциональной недостаточности и мышечной гипотро-
фии поврежденной конечности, формированию постим-
мобилизационных контрактур смежных суставов и общей N.J. Serova, M.K. Tishchenko, S.J. Nikishov Scientific Research Institute of Urgent Pediatric Surgery and Traumatology, Moscow Contacts: В статье представлены результаты сравнительного анализа лечения переломов костей голени у 102 детей в возрасте
от 4 до 18 лет. Основную группу, в которой после оперативного лечения использовался метод пневматической ими-
тации опорной нагрузки аппаратом «Корвит» на травмированную и здоровую нижние конечности, составил 51 (50%)
пациент. В контрольную группу, в которой не применяли данный метод лечения, вошел 51 (50%) больной. Группы
были сравнимы по возрасту, механизму и локализации травмы, методу оперативного вмешательства и комплексной
терапии послеоперационного периода. В основной группе отмечены более ранние сроки уменьшения интенсивности
болевого синдрома, отека мягких тканей, восстановления движений в смежных суставах и нормализация показате-
лей соматометрии, что позволило раньше разрешить пациенту начать хождение и сократить сроки лечения. Ключевые слова: дети, пневматическая имитация опорной нагрузки, перелом, кости голени, отек, методы фиксации. 74 р
р
р
у
р
р
: дети, пневматическая имитация опорной нагрузки, перелом, кости голени, отек, методы фиксации. Применение метода пневматической
имитации опорной нагрузки при
переломах костей голени у детей Contacts:
Natal’ya Serova, pediatric surgeon, graduate student of the department of urgent pediatric surgery and trauma in children of the Scientific Center
of Children’s Health of the Russian Academy of Medical Science
Address: B. Polyanka, 22, Moscow, 119180, Tel.: (495) 633-58-00, e-mail: serova_tu@yahoo.com
Article received: 09.06.2012, Accepted for publication: 03.08.2012 Н.Ю. Серова, М.К. Тищенко, С.О. Никишов Научно-исследовательский институт неотложной детской хирургии и травматологии Департамента
М The method of pneumatic imitation of weight-bearing
in children with shin fractures The article contains a comparative analysis of shin fracture treatment in 102 children at the age of 4–18 years old. The main group
consisted of 51 (50%) children, who received postoperative treatment according to the method of pneumatic imitation of weight-
bearing both on health and injured limbs with «Korvit» apparatus. The control group consisted of 51 (50%) patients who did not received
the afore-mentioned method of postoperative treatment. The groups were comparable on age, trauma mechanism and localization,
surgical operation and complex postoperative therapy. Children of the first group were found to have shorter period of time needed
to achievement of pain relief, soft tissue swelling decrease, restoration of the movements in adjacent joints and somatometry values
normalization, which allowed earlier verticalization and shorter period of hospitalization. ey words: pneumatic imitation of weight-bearing, fracture, shin bones, swallowing, fixation methods, children. В настоящее время отработана хирургическая техника
миниинвазивного металлоостеосинтеза (ММОС) [2, 7]. В лечении переломов костей голени используют такие
фиксаторы, как TENы — гибкие титановые штифты, LCP —
блокируемая компрессирующая пластина, UTN — интра-
медуллярные блокируемые гвозди, компрессирующие
винты и Hcs (канюлированные) винты. Преимуществами
ММОС по сравнению с классическими методами являют-
ся минимальная травматичность, отсутствие необходимо-
сти в оперативном доступе в зоне перелома, оптимальная
репозиция и стабилизация отломков при отсутствии внеш-
ней иммобилизации. Современные технологии позволяют
использовать аппаратные методики и являются принци-
пиально важным подходом в комплексном лечении, т. к. они сохраняют и поддерживают функции поврежденной
конечности уже с первых сут после оперативного лечения
[2, 3, 7]. Ультразвуковое исследование мягких тканей
и костей дает возможность уточнить характер и степень
повреждения и смещения отломков, а также циркуляцию
в магистральных сосудах и в зоне образования костной
мозоли [8, 9]. Однако в научной литературе нет описания
методик соматометрического и эхографического исследо-
вания в динамике при переломах костей голени у детей. В ходе изучения проблем лечения детей с подобными
травмами в мире стало известно, что детскими специали-
стами из Американской академии ортопедической хирур-
гии были проанализированы научные материалы, посвя-
щенные лечению переломов нижних конечностей у детей. Из их заключения следует, что ни в одной из публикаций
за период с 1996 по 2008 гг. нет данных о необходимом
объеме комплексного лечения пациентов, включающего
в себя программы управления болевым синдромом, и нет
обоснованных практических рекомендаций по восстанов-
лению функций конечностей [10]. Аппаратные методики
в комплексном лечении применяют у взрослых пациентов
на поздних этапах восстановительного лечения, начиная
с 3–5-й нед. The method of pneumatic imitation of weight-bearing
in children with shin fractures Известен способ раннего применения пре-
рывистой пневмокомпрессии, который благоприятствует
снижению интенсивности болевого синдрома, уменьшает
отек мягких тканей, а также снижает вероятность воз-
никновения тромбоза глубоких вен нижних конечностей
на стационарном этапе лечения переломов нижних конеч-
ностей у взрослых больных [11]. Аппарат пневматической
имитации опорной нагрузки (ПИОН) «Корвит» моделирует
опорные реакции с использованием принципа пневмоме-
ханического давления на соответствующие опорные зоны
стопы с помощью специальных пневмокамер в разрабо-
танных режимах реальных движений. Согласно работам,
выполняемым в институте медико-биологических про-
блем, пневматический имитатор опорной нагрузки, воз-
действуя путем стимуляции опорных зон и проприорецеп-
торов, по данным функциональной магнитно-резонансной томографии, формирует афферентный поток импульсов,
который оказывает регулирующее действие на контро-
лирующие движения структуры центральной нервной
системы, такие как первичные моторные области и допол-
нительные зоны активации (первичная сенсорная кора,
поля Бродмана, нижние отделы постцентральных изви-
лин, парацентральные дольки, области верхних и ниж-
них теменных долей, дорсолатеральные префронтальные
области коры), отвечающие за выполнение сложного
локомоторного акта — шага и ходьбы [12]. Специальных
исследований, посвященных разработке и оценке ком-
плексного лечения переломов костей голени у детей
с использованием аппаратных методик на ранних сроках
послеоперационного периода, в доступной литературе мы
не встретили. Цель исследования: оценить эффективность ком-
плексного лечения переломов костей голени у детей,
оперированных по малоинвазивным методикам метал-
лоостеосинтеза, с применением метода ПИОН в раннем
послеоперационном периоде. Участники исследования В исследование были включены 102 ребенка в воз-
расте от 4 до 18 лет, поступившие в НИИ НДХиТ за период
с 2010 по 2012 гг. для хирургического лечения по пово-
ду переломов костей голени. Из общего числа детей
40 (39%) — девочки и 62 (61%) — мальчики. Половина
пациентов составила основную группу, в которой поми-
мо общепринятого комплексного лечения применялась
аппаратная имитация опорной нагрузки, 51 (50%) — груп-
пу сравнения. Обе группы были сопоставимы по воз-
расту, полу, механизму и локализации травмы, срокам
и методу оперативного вмешательства, виду фиксато-
ров. Дети были распределены на 4 возрастные группы:
1-я — от 4 до 6 лет, 2-я — от 7 до 10, 3-я — от 11 до 14,
4-я — от 15 до 18. Большая часть наблюдаемых были
пациентами 3 и 4-й возрастных групп. Средний возраст
больных составил 12 лет 6 мес ± 2 года 4 мес (табл. 1). Уличный травматизм стал причиной перелома у 58
(57%) детей, спортивный, в т. ч. полученный на уроке
физкультуры, — у 20 (19,6%), дорожный — у 14 (13,7%),
бытовой — у 10 (9,7%). Диафизарный перелом костей
средней трети голени был диагностирован у 26 (25,5%)
человек, диафизарный перелом костей нижней трети
голени — у 10 (9,7%), метаэпифизеолиз дистального
отдела большеберцовой кости — у 31 (30,4%), перелом
передненаружного отдела большеберцовой кости —
у 17 (16,7%), двухлодыжечный перелом — у 4 (4%),
перелом медиальной лодыжки — у 11 (10,8%), эпифи-
зеолиз дистального отдела большеберцовой кости —
у 3 (2,9%). Закрытые переломы составили основную ВОПРОСЫ СОВРЕМЕННОЙ ПЕДИАТРИИ /2012/ ТОМ 11/ № 4 Показатель
Группа
Общая характеристика
Основная группа, n = 51
Группа сравнения, n = 51
Мальчики
62 (61%)
31 (61%)
31 (61%)
Девочки
40 (39%)
20 (39%)
20 (39%)
Возраст 4–6 лет
6 (6%)
3 (5,9%)
3 (5,9%)
Возраст 7–10 лет
8 (7,8%)
5 (9,8%)
3 (5,9%)
Возраст 11–14 лет
55 (54%)
27 (52,9%)
28 (54,9%)
Возраст 15–18 лет
33 (32%)
16 (31,4%)
17 (33,3%)
Средний возраст
12 лет 6 мес ±2 года 4 мес
12 лет 6 мес ±2 года 4 мес
12 лет 6ме с±2 года 4 мес
Таблица 1. Сравнение пациентов по полу и возрасту Таблица 1. Сравнение пациентов по полу и возрасту движений, отечность конечности) и ультразвукового иссле-
дования. часть переломов — у 98 (96%) пациентов, открытые —
лишь у 4 (4%). Перелом одной кости голени был диа-
гностирован у 60 (59%) детей, обеих костей голени —
у 42 (41%). Методы исследования Всем больным был выполнен миниинвазивный
металлоостеосинтез, во всех случаях отсутствовала
наружная иммобилизация или аппаратная внешняя
фиксация: 86 (84%) пациентам выполнено закрытое
реконструктивное малоинвазивное оперативное вме-
шательство, 16 (16%) — открытое. При лечении ука-
занных повреждений использовали различные фик-
саторы ММОС: компрессирующие винты установили
38 (37%) детям, винты Hcs — 29 (28%), в том числе
с дополнительной фиксацией малоберцовой кости спи-
цей — 9 пациентам, LCP — 12 (12%), UTN — 12 (12%),
TENы — 11 (11%). Больным основной группы и группы
сравнения назначили однотипное лечение (табл. 3). Статистическая обработка данных Компьютерный анализ фактических данных осущест-
вляли в программах Microsoft Excel XP и SPSS Statistics
17.0 с использованием мультифакторного дисперсионно-
го анализа показателей в динамике и t-критерия равен-
ства средних значений для оценки результатов лечения. Различия считали достоверными при p < 0,05. Участники исследования Изолированные переломы диагностировали
у 92 (90%) детей, повреждение конечности с явлениями
неврита имело место у 4 (4%), сочетанная травма —
у 5 (4,9%): закрытая черепно-мозговая травма, сотря-
сение головного мозга — у 4, компрессионный пере-
лом позвоночника — у 1 (табл. 2). В общей структуре
преобладали переломы со смещением — у 86 (84%)
наблюдаемых. Большинство детей (76–75%) поступили
в первые сутки после травмы и были прооперированы
в срочном порядке. Скелетное вытяжение как основ-
ной метод лечения не применяли, он был использован
с целью первичной иммобилизации у 15 (16%) пациен-
тов в периоде, предшествующем оперативному вмеша-
тельству, длительностью от 1 до 5 сут. Соматометрический контроль включал измерение
длины окружности обеих конечностей в симметричных
областях, измерение объема и амплитуды движений
в голеностопных суставах. Полученные показатели сопо-
ставляли, суммировали и сравнивали с показателями для
здоровой конечности, которые принимали за норму. Ультразвуковое исследование выполняли после опера-
ции на аппаратах экспертного класса «SonoSite MicroMaxx»
(SonoSite Inc., США), сравнивая травмированную конеч-
ность со здоровой, оценивая повреждения, толщину мягких
тканей голени, измерение и описание m. Tibialis anterior
на сроках 1, 6, 10-е сут и после разрешения опорной
нагрузки, на 60-е сут со дня оперативного вмешательства. Контрольные осмотры после выписки проводили через
3–4 нед, 45 дней и 2 мес после установки металлокон-
струкции. Результаты оценивали по нескольким параме-
трам: срокам вертикализации, нормализации размеров
конечности и срокам начальной консолидации переломов. Примечание. ББК — большеберцовая кость; ЗЧМТ — закрытая черепно-мозговая травма. шеберцовая кость; ЗЧМТ — закрытая черепно-мозговая травма. РЕЗУЛЬТАТЫ И ОБСУЖДЕНИЕ Каждый ребенок основной группы с первого после-
операционного дня получал процедуры ПИОН с помощью
аппарата модели «Корвит» (регистрационное удостове-
рение № ФСР 2009/04901 от 25 мая 2009 г.) продолжи-
тельностью 10 мин. В первый послеоперационный день
давление в пневматических подушках устанавливали Оценку эффективности применения методики ПИОН
осуществляли по числовой, вербальной аналоговой либо
(у детей с 4 до 8 лет) мимической шкале болевого синдро-
ма от 0 до 10 баллов с помощью соматометрии (амплитуда Непрерывное профессиональ Таблица 2. Сравнение детей по характеристикам перелома Примечание ББК
большеберцовая кость; ЗЧМТ
закрытая черепно мозговая травма
Таблица 2. Сравнение детей по характеристикам перелома
Показатель
Группы пациентов
Общая
характеристика
Основная группа,
n = 51
Группа сравнения,
n = 51
Диафизарный перелом в среднем сегменте ББК
26 (25,5%)
13 (25,5%)
13 (25,5%)
Диафизарный перелом в нижнем сегменте ББК
10 (9,7%)
5(9,8%)
5(9,8%)
Метаэпифизеолиз дистального отдела ББК
31(30,4%)
15 (31,4%)
16 (31,4%)
Перелом передненаружного отдела ББК
17 (16,7%)
9 (17,6%)
8 (15,7%)
Двухлодыжечный перелом
4 (4%)
2 (3,9%)
2 (3,9%)
Перелом медиальной лодыжки ББК
33 (32%)
6 (11,8%)
5 (9,8%)
Эпифизеолиз дистального отдела ББК
3 (2,9%)
1 (2%)
2 (3,9%)
Закрытый перелом
98 (96%)
49 (96%)
49 (96%)
Открытый перелом
4 (4%)
2 (3,9%)
2 (3,9%)
Перелом ББК
60 (59%)
28 (54,9%)
32 (62,7%)
Перелом обеих костей голени
42 (41%)
23 (45,1%)
19 (37,3%)
Перелом со смещением
96 (95%)
48 (95%)
48 (95%)
Перелом без смещения
6 (5,8%)
3 (5,9%)
3 (5,9%)
Изолированный перелом
92 (90%)
46 (90,2%)
46 (90,2%)
Неврит
4 (4%)
1 (2%)
3 (5,9%)
Сочетанная травма: ЗЧМТ
5 (9,8%)
3 (5,8%)
2 (4%)
Сочетанная травма: компрессионный перелом
1 (1%)
1 (2%)
Нет Таблица 3. Сравнение лечения в основной и контрольной группах Таблица 3. Сравнение лечения в основной и контрольной группах Примечание. МБК — малоберцовая кость; ММОС — малоинвазивный металлоостеосинтез; LCP — блокированная
компрессирующая пластина; UTN — солидный штифт для большеберцовой кости; TEN — титановый эластичный штифт. РЕЗУЛЬТАТЫ И ОБСУЖДЕНИЕ Показатель
Группы пациентов
Общая
характеристика
Основная группа,
n = 51
Группа сравнения,
n = 51
Скелетное вытяжение
15 (16%)
8 (16%)
8 (16%)
Операция в день поступления
30 (29,4%)
15 (29,4%)
15 (29,4%)
Операция в первые 3 сут
64(62,7%)
33 (64,6%)
31 (60,8%)
Операция на 1-й нед
4 (3,9%)
2 (4%)
2 (4%)
Операция на 2-й нед
3 (2,9%)
1 (2%)
2 (4%)
Закрытое оперативное вмешательство + ММОС
86 (84%)
44 (86,3%)
42 (82,4%)
Открытое оперативное вмешательство + ММОС
16 (16%)
7 (13,7%)
9 (17,6%)
Компрессирующий винт
55 (54%)
20 (39,2%)
18 (35,3%)
Винт канюлированный
33 (32%)
14 (27,5%)
15 (29,4%)
LCP-пластина
12 (12%)
6 (11,8%)
6 (11,8%)
Гвоздь UTN
12 (12%)
5 (9,8%)
7 (11,3%)
TENы
11 (11%)
6 (11,8%)
5 (9,8%)
Дополнительная спица-фиксация МБК
18 (17,6%)
9 (17,6%)
9 (17,6%) ечание. МБК — малоберцовая кость; ММОС — малоинвазивный металлоостеосинтез; LCP — блокированная
ессирующая пластина; UTN — солидный штифт для большеберцовой кости; TEN — титановый эластичный штифт. 77 ВОПРОСЫ СОВРЕМЕННОЙ ПЕДИАТРИИ /2012/ ТОМ 11/ № 4 мог сохраняться игровой элемент в общении. У 47 (93%)
пациентов основной группы отмечено уменьшение интен-
сивности болевого синдрома, исчезновение страха движе-
ния в смежных суставах, снижение отечности конечности. Лечебный эффект был очевиден, когда уменьшался боле-
вой синдром, поскольку отсутствие боли позволяло детям
заниматься лечебной физкультурой активнее по сравне-
нию с пациентами группы сравнения (табл. 4, рис. 1). на минимальном уровне (10 кПа). С целью максимально
быстрого восстановления функции поврежденной конеч-
ности авторами разработана методика проведения ПИОН. С первых сут после оперативного вмешательства режим
ходьбы устанавливался дифференцированно. У детей
младшего возраста (до 6 лет) — 8 процедур по 10 мин
с давлением 10–20 кПа в режимах «медленной ходьбы»
(75 циклов в минуту, ц/мин; длительность шага 800 мс)
либо «средней ходьбы» (120 ц/мин, 500 мс), либо «быстрой
ходьбы» (150 ц/мин, 400 мс). У детей старше 6 лет —
8 процедур по 10 мин с давлением 20–30 кПа в режимах
«средней ходьбы» (120 ц/мин, 500 мс) либо «быстрой ходь-
бы» (150 ц/мин, 400 мс). Дети охотно принимали процеду-
ры ПИОН, которые не вызывали у них негативной реакции
вследствие безболезненности и отсутствия каких-либо
неприятных ощущений в процессе проведения. При этом Сравнение обеих групп в день операции, после нее, на
1-е и 2-е сут не показало достоверных отличий. РЕЗУЛЬТАТЫ И ОБСУЖДЕНИЕ На 1-е сут после оперативного лечения показатели раз-
ницы толщины мягких тканей поврежденного сегмента
по сравнению с симметричным участком здоровой конеч-
ности составили в обеих группах 0,55 ± 0,04 см (основ-
ная группа и группа сравнения сопоставимы в начале
лечения), на 6-е сут — 0,47 ± 0,39 и 0,54 ± 0,04, на 10-е
сут — до 0,35 ± 0,03 и 0,44 ± 0,03 см, соответственно. Такое состояние наблюдаемых сохранялось на контроль-
ном эхографическом исследовании на 60-е сут после
перелома, т. е. спустя 3 нед после назначения опорной
нагрузки: 0,16 ± 0,01 в основной группе и 0,38 ± 0,03 см
в группе сравнения. Подобные изменения происходили
с m. Tibialis anterior в динамике. Изменения степени
выраженности отека по данным ультразвукового иссле-
дования пациентов обеих групп представлены в табл. 6,
7 и на рис. 4, 5. В целом снижение величины отечности
в динамике при применении ПИОН «Корвит» в комплекс-
ном лечении у пациентов основной группы оказалось
статистически значимым (p < 0,01). Таким образом, есть основания говорить о том, что
по тяжести полученной травмы и величине отека основная
группа и группа сравнения были сопоставимы. Однако,
начиная со 2-х сут отмечено значимое отличие между
показателями обеих групп. К 5-м сут соматометрический
показатель разницы измерений поврежденной конечно-
сти по сравнению со здоровой в основной группе соста-
вил 6,35 ± 0,57 см, в группе сравнения — 9,11 ± 0,59,
а по сравнению с исходными данными в динамике были
установлены достоверно различающиеся показатели
уменьшения степени выраженности отека в основной
группе (p < 0,01). К моменту выписки из стационара
у пациентов основной группы разница сумм измерений
составила 2,18 ± 0,4. Не отмечено и нарастания отека
в течение последующих суток; те же показатели на кон-
трольном осмотре на 30-е сут составили (–0,27) ± 0,19,
а на 60-е сут — 0,15 ± 0,11. В группе сравнения отек про-
должал сохраняться и на 10-е сут (3,56 ± 0,47), повреж- Оценку результатов лечения проводили по 3 пара-
метрам. Вертикализация пациентов в основной группе
происходила, по средним данным, на 1,62 ± 0,09 сут,
тогда как в группе сравнения — на 2,12 ± 0,11 (p < 0,01). Нормализация размеров конечностей в основной
группе — на 26,94 ± 2,53 сут, в группе сравнения — Таблица 5. Динамика соматометрических показателей здоровой и поврежденной конечности Таблица 5. Динамика соматометрических показателей здоровой и поврежденной конечности Сроки
от оперативного
вмешательства, сут
Разница длины окружности поврежденной
и здоровой конечности, см
Разница объема движений смежных суставов
поврежденной и здоровой конечности, град. РЕЗУЛЬТАТЫ И ОБСУЖДЕНИЕ Разница
измерений показателей поврежденной конечности по
сравнению со здоровой на момент оперативного вме-
шательства у основной группы составила 9,18 ± 0,68 см,
у группы сравнения — 9,4 ± 0,6; после операции —
8,92 ± 0,68 и 9,19 ± 0,64 см, соответственно; нарастала
в 1-й день после операции (10,5 ± 0,67 и 11,19 ± 0,62). Примечание. Статистически значимые различия показателей: * — в процессе лечения по сравнению с показателями до лечения
(р < 0,05); ** — сравнение показателей основной группы и группы сравнения (р < 0,05). Динамику болевых ощущений оценивали
по числовой, вербальной аналоговой либо (у детей с 4 до 8 лет) мимической шкале болевого синдрома от 0 до 10 баллов. Таблица 4. Динамика болевого синдрома
Дни
До
операции
После
операции
2
3
4
5
6
7
8
9
10
11
Основная
группа
2,784 ± 0,164
6,156 ± 2,04
5,04 ± 1,77
3,02 ± 0,163
1,68 ± 0,142*,**
0,9 ± 0,113*,**
0,3 ± 0,071*,**
0,142 ± 0,048*,**
0
0
0
0
Группа
сравнения
2,882 ± 0,077
6,098 ± 0,168
5,431 ± 0,141
4,176 ± 0,176
3,196 ± 0,208**
2,176 ± 0,189**
1,431 ± 0,156**
1,019 ± 0,117**
0,607 ± 0,079**
0,313 ± 0,066
0,098 ± 0,042
0,0588 ± 0,0332 Таблица 4. Динамика болевого синдрома Примечание. Статистически значимые различия показателей: * — в процессе лечения по сравнению с показателями до лечения
(р < 0,05); ** — сравнение показателей основной группы и группы сравнения (р < 0,05). Динамику болевых ощущений оценивали
по числовой, вербальной аналоговой либо (у детей с 4 до 8 лет) мимической шкале болевого синдрома от 0 до 10 баллов. Рис. 1. Динамика болевого синдрома денная конечность была изменена и после выписки
из стационара — (–1,43) ± 0,36, у нее присутствова-
ли признаки гипотрофии. Отек конечности у пациентов
группы сравнения был диагностирован и после назна-
чения опорной нагрузки в течение 3 нед (1,02 ± 0,34). Динамика изменений степени выраженности отека и
объема движений у пациентов основной группы и группы
сравнения представлена в табл. 5 и на рис. 2, 3. Баллы
Сутки
70
60
50
40
30
20
10
ДО
ПО
2
3
4
5
6
7
8
9
10
11
0
Основная группа
Группа сравнения Согласно данным ультразвукового контроля, про-
явление отека и изменения структурности m. Tibialis
anterior у пациентов основной группы носили транзи-
торный характер, тогда как в группе сравнения они
сохранялись в течение длительного периода времени. РЕЗУЛЬТАТЫ И ОБСУЖДЕНИЕ Сравнение амплитуды движений в голеностопном
суставе
Рис. 5. Сравнение толщины m. Tibialis anterior в динамике
по данным ультразвукового исследования
Таблица 6. Сравнение соматометрических показателей в динамике по данным ультразвукового исследования
Т б
7 С
Tibi li
t
i
Примечание. Отек — разница толщины мягких тканей поврежденной и здоровой конечности, измеряемая в симметричных областях. Статистически значимые различия показателей: * — в процессе лечения по сравнению с показателями до лечения (р < 0,05);
** — сравнение показателей основной группы и группы сравнения (р < 0,05). Отек, 2-е сут
Отек, 6-е сут
Отек, 10-е сут
Отек, 60-е сут
Основная группа
0,55 ± 0,04
0,47 ± 0,39*,**
0,35 ± 0,03*,**
0,16 ± 0,01*,**
Группа сравнения
0,55 ± 0,04
0,54 ± 0,04**
0,44 ± 0,03**
0,38 ± 0,03** Рис. 3. Сравнение амплитуды движений в голеностопном
суставе Рис. 2. Динамика соматометрических показателей здоровой
и поврежденной конечности град. Сутки
90
80
70
60
50
40
30
20
10
ПО
2
3
4
5
6
7
8
9
10
11
30
60
0
Основная группа
Группа сравнения см
Сутки
12
10
8
6
4
2
0
2
ДО ПО
2
3
4
5
6
7
8
9
10 11 30 60
4
Основная группа
Группа сравнения см
Сутки
0,3
0,25
0,2
0,15
0,1
0,05
2
6
10
60
0
Основная группа
Группа сравнения
Рис. 5. Сравнение толщины m. Tibialis anterior в динамике
по данным ультразвукового исследования Рис. 5. Сравнение толщины m. Tibialis anterior в динамике
по данным ультразвукового исследования Рис. 4. Сравнение соматометрических показателей в динамике
по данным ультразвукового исследования Рис. 5. Сравнение толщины m. Tibialis anterior в динамике
по данным ультразвукового исследования Рис. 4. Сравнение соматометрических показателей в динамике
по данным ультразвукового исследования см
Сутки
0,6
0,5
0,4
0,3
0,2
0,1
2
6
10
60
0
Основная группа
Группа сравнения ВОПРОСЫ СОВРЕМЕННОЙ ПЕДИАТРИИ /2012/ ТОМ 11/ № 4 на 42,29 ± 2,82 (p < 0,01). Сроки проявления началь-
ной консолидации на контрольных рентгенограммах
в динамике после выписки из стационара составили
41,76 ± 1,21 сут в основной группе и 51 ± 1,54 — в груп-
пе сравнения (p < 0,05), данные представлены в табл. 8. Таким образом, можно утверждать, что у детей, получав-
ших лечение с применением ПИОН «Корвит», улучшилось
общее самочувствие и функциональные возможности
поврежденной конечности, поддерживался тонус мышц
поврежденной конечности, повышалась общая двига- Таблица 6. Сравнение соматометрических показателей в динамике по данным ультразвукового исследования
Примечание. РЕЗУЛЬТАТЫ И ОБСУЖДЕНИЕ Основная группа
Группа сравнения
Основная группа
Группа сравнения
n = 51
n = 51
n = 51
n = 51
До операции
9,18 ± 0,68
9,4 ± 0,6
0
0
После операции
8,92 ± 0,68
9,19 ± 0,64
0
0
2-е
10,5 ± 0,67
11,19 ± 0,62
21,9 ± 2,9
22,9 ± 2,9
3-е
10,3 ± 0,59
11,32 ± 0,67
44,7 ± 2,9
38,4 ± 3
4-е
8,84 ± 0,605
10,54 ± 0,65
59,5 ± 1,8
51,1 ± 2,5
5-е
7,69 ± 0,6
9,84 ± 0,61
67,6 ± 1,4
58,5 ± 2,4
6-е
6,35 ± 0,57
9,11 ± 0,59
71,2 ± 1,1
61,8 ± 2,1
7-е
5,43 ± 0,58
8,14 ± 0,6
73,8 ± 0,9
67,5 ± 1,3
8-е
4,55 ± 0,56
6,95 ± 0,58
75,7 ± 0,9
70,2 ± 1
9-е
3,94 ± 0,44
5,58 ± 0,50
77,2 ± 0,7
73,3 ± 0,7
10-е
2,97 ± 0,42
4,66 ± 0,49
78 ± 0,7
75,3 ± 0,5
11-е
2,18 ± 0,4
3,56 ± 0,47
78,4 ± 0,6
75,8 ± 0,55
30–45-е
–0,27 ± 0,19
–1,43 ± 0,36
79,2 ± 0,03
76,4 ± 0,51
60-е сут
0,15 ± 0,11
1,02 ± 0,34
79,4 ± 0,4
77,9 ± 0,45
Таблица 5. Динамика соматометрических показателей здоровой и поврежденной конечности на 42,29 ± 2,82 (p < 0,01). Сроки проявления началь-
ной консолидации на контрольных рентгенограммах
в динамике после выписки из стационара составили
41,76 ± 1,21 сут в основной группе и 51 ± 1,54 — в груп-
пе сравнения (p < 0,05), данные представлены в табл. 8. Таким образом, можно утверждать, что у детей, получав-
ших лечение с применением ПИОН «Корвит», улучшилось
общее самочувствие и функциональные возможности
поврежденной конечности, поддерживался тонус мышц
поврежденной конечности, повышалась общая двига-
см
Сутки
12
10
8
6
4
2
0
2
ДО ПО
2
3
4
5
6
7
8
9
10 11 30 60
4
Основная группа
Группа сравнения
см
Сутки
0,6
0,5
0,4
0,3
0,2
0,1
2
6
10
60
0
Основная группа
Группа сравнения
град. Сутки
90
80
70
60
50
40
30
20
10
ПО
2
3
4
5
6
7
8
9
10
11
30
60
0
Основная группа
Группа сравнения
см
Сутки
0,3
0,25
0,2
0,15
0,1
0,05
2
6
10
60
0
Основная группа
Группа сравнения
Рис. 2. Динамика соматометрических показателей здоровой
и поврежденной конечности
Рис. 4. Сравнение соматометрических показателей в динамике
по данным ультразвукового исследования
Рис. 3. РЕЗУЛЬТАТЫ И ОБСУЖДЕНИЕ Отек — разница толщины мягких тканей поврежденной и здоровой конечности, измеряемая в симметричных областях. Статистически значимые различия показателей: * — в процессе лечения по сравнению с показателями до лечения (р < 0,05);
** — сравнение показателей основной группы и группы сравнения (р < 0,05). Отек, 2-е сут
Отек, 6-е сут
Отек, 10-е сут
Отек, 60-е сут
Основная группа
0,55 ± 0,04
0,47 ± 0,39*,**
0,35 ± 0,03*,**
0,16 ± 0,01*,**
Группа сравнения
0,55 ± 0,04
0,54 ± 0,04**
0,44 ± 0,03**
0,38 ± 0,03** Таблица 6. Сравнение соматометрических показателей в динамике по данным ультразвукового исследования Таблица 7. Сравнение толщины m. Tibialis anterior в динамике по данным ультразвукового исследования
Примечание. m. Tibialis anterior — разница толщины m. Tibialis anterior поврежденной и здоровой конечности, измеряемая
в симметричных областях. Статистически значимые различия показателей: * — в процессе лечения по сравнению с показателями
до лечения (р < 0,05); ** — сравнение показателей основной группы и группы сравнения (р < 0,05). m. Tibialis anterior,
2-е сут
m. Tibialis anterior,
6-е сут
m. Tibialis anterior,
10-е сут
m. Tibialis anterior,
60-е сут
Основная группа
0,23 ± 0,01
0,19 ± 0,01*,**
0,09 ± 0,01*,**
0,04 ± 0,01*,**
Группа сравнения
0,22 ± 0,03
0,28 ± 0,02**
0,24 ± 0,03**
0,073 ± 0,04** Таблица 7. Сравнение толщины m. Tibialis anterior в динамике по данным ультразвукового исследования ение толщины m. Tibialis anterior в динамике по данным ультразвукового исследования Примечание. m. Tibialis anterior — разница толщины m. Tibialis anterior поврежденной и здоровой конечности, измеряемая
в симметричных областях. Статистически значимые различия показателей: * — в процессе лечения по сравнению с показателями
до лечения (р < 0,05); ** — сравнение показателей основной группы и группы сравнения (р < 0,05). Таблица 8. Результаты лечения детей основной группы и группы сравнения Сроки
Вертикализации, сут
Нормализация показателей, сут
Консолидация, сут
Группа
Основная
группа
Группа
сравнения
Основная
группа
Группа
сравнения
Основная
группа
Группа
сравнения
Данные
1,63 ± 0,09*
2,12 ± 0,11*
26,94 ± 2,52*
42,29 ± 2,82*
37,51 ± 1,54*
41,7 ± 1,22*
Примечание. * — сравнение показателей результатов лечения основной группы и группы сравнения (р < 0,05). Рис. 6. Пациент Н.,
14 лет, во время
проведения процедуры —
на 2-е сут после открытого
оперативного вмешательства,
металлоостеосинтеза
по поводу закрытого перелома
передненаружного отдела
дистального эпифиза левой
большеберцовой кости
со смещением ЗАКЛЮЧЕНИЕ тельная активность и про-
исходил ранний перевод
с постельного режима на
общий. Предложенные методики оценки поврежденной
конечности по соматометрическим показателям и эхо-
графического мониторинга у детей с переломами костей
голени, оперированных по методике миниинвазивно-
го металлоостеосинтеза, позволяют объективизировать
характер и степень повреждения, в динамике проследить
за изменениями тканей. Согласно усовершенствованной
методике проведения процедур, аппаратную пневма-
тическую имитацию опорной нагрузки (ПИОН) целесоо-
бразно использовать с первых сут после оперативного
вмешательства (рис. 6). Режим ходьбы определяется
дифференцировано. Применение указан -
ной методики способству-
ет раннему восстановле-
нию ходьбы за счет сохра-
нения опороспособности,
что достигается путем под-
держания функциональ-
ного состояния связочно-
мышечного аппарата по-
врежденной нижней ко-
нечности. Ослож нений
или отрицательного воз-
действия у пациентов не
наблюдалось. Осевая на-
грузка была разрешена
через 1 мес: дети практи-
чески сразу начали ходить
без хромоты и уже через
несколько
дней
могли
посещать детские учреж-
дения. Установлена прямая связь соматометрических и эхо-
графических показателей в зависимости от времени
послеоперационного течения и применения ПИОН. Использование аппарата в раннем послеоперационном
периоде не оказывает негативного воздействия, уско-
ряет репаративные процессы. Показатели соматометри-
ческих измерений, объема движений и ультразвукового
обследования свидетельствуют об эффективности про-
цедур и более ранней активизации пациентов с первых
сут после оперативного вмешательства. 80 Непрерывное профессиональное образование Таким образом, включение ПИОН в комплексное
лечение переломов костей голени у детей улучшает
результаты лечения, сокращая сроки восстановления,
облегчая состояние пациента. Применение настоящей
методики в раннем послеоперационном периоде у детей
с переломами костей голени может быть рекомендова-
но для использования в специализированных лечебных
учреждениях. Непрерывное профессиональ У 28 пациентов груп-
пы сравнения жалобы
на отек, хромоту сохранялись до 2 мес, отмечалась
гипотрофия поврежденной конечности при наличии
отека мягких тканей по результатам ультразвукового
иссле дования. REFERENCES 6. Mel'tsin I. I. Differentsirovannyy
metalloosteosintez
pri
diafizarnykh perelomakh dlinnykh trubchatykh kostey u detey
[Differentiated Osteosynthesis at Shaft Fractures of Long Bones in
Children] Synopsis of thesis for the degree of Candidate of Medical 6. Mel'tsin I. I. Differentsirovannyy
metalloosteosintez
pri
diafizarnykh perelomakh dlinnykh trubchatykh kostey u detey
[Differentiated Osteosynthesis at Shaft Fractures of Long Bones in
Children]. Synopsis of thesis for the degree of Candidate of Medical
Science. М. 2009. 1. Bykov V. M., Kovshova M. F., Gorshenina O. V. Konferentsiya
detskikh travmatologov-ortopedov Rossii «Aktual'nyye voprosy
detskoy travmatologii i ortopedii»: Sbornik tezisov [Conference of
Pediatric Traumatologists-Orthopedists of Russia “Topic Issues of
Pediatric Traumatology and Orthopedics”: Collection of Theses]. М. 2001. 327 p. Children]. Synopsis of thesis for the degree of Candidate of Medical
Science. М. 2009. g
Pediatric Traumatology and Orthopedics”: Collection of Theses]. М. 2001. 327 p. 7. Puzhitskiy L. B.,
Ratin D. A.,
Nikishov S. O. and
others. MargoAnterior. 2009; 3: 10–12. 2. Krikunov A. I., Puzhitskiy L. B. Detskaya khirurgiya — Pediatric
Surgery. 2011; 3: 22–24. 8. Sinitsina N. V., Vatolin K. V., Vybornov D.Yu. and others. Detskaya
khirurgiya — Pediatric Surgery. 2010; 3: 14–17. 3. Petrov A. G., Akinfiyev A. V. Ekstrakortikal'nyy osteosintez pri
lechenii diafizarnykh perelomov dlinnykh trubchatykh kostey u detey
starshego vozrasta [Extracortical Osteosynthesis at Treatment of
Shaft Fractures of Long Bones in Children of Later Years]. Kazan: ID
«Praktika». 2009. 16 p. 9. Cross K. P. Clin. Ped. Еmerg. Med. 2011; 12 (1): 27–36. 10. American Academy of Orthopedic Surgeons. Study for
the new cli ni cal guidelines of leg fractures in children. URL:
http://www.aaos.org 4. Chukina Ye. A. Kompleksnoye vosstanovitelnoye lecheniye
bol'nykh s perelomami distal'nogo otdela kostey goleni i lodyzhek
[Complex Recovery Treatment of Patients With Fractures of Distal
Aspect of Cnemis and Malleolar Bones]. Synopsis of thesis for the
degree of Candidate of Medical Science. М. 1997. 11. Chukhlina U. A., Shchepkina V. A., Klyuvkin I.Yu. and others. Fizioterapiya, bal'neologiya i reabilitatsiya — Physical Therapy,
Balneology and Rehabilitation. 2010; 3: 14–17. 12. Khunustdinova D. R. Rol' opornoy afferentatsii v podderzhanii
skorostno-silovykh svoystv i vynoslivosti antigravitatsionnykh myshts
[Role of Basic Afference in Support of Speed-Power Properties and
Endurance of Antigravity Muscles]. Synopsis of thesis for the degree
of Candidate of Medical Science. М. 2007. 5. Xiao M., Li J., Zhang X., Zhao Z. Factors affecting functional
outcome of Sichuan-earthquake survivors with tibial shaft fractures:
a follow-up study. J. Rehabil. Med. REFERENCES 2011; 43 (6): 515–520.
|
https://openalex.org/W2561154418
|
https://businessperspectives.org/images/pdf/applications/publishing/templates/article/assets/8144/PPM_2016_04cont_Sipho.pdf
|
English
| null |
Planning of marketing communication strategies by car dealerships
|
Problems and perspectives in management/Problems & perspectives in management
| 2,016
|
cc-by
| 7,555
|
businessperspectives.org “Planning of marketing communication strategies by car dealerships” Planning of marketing communication strategies by car dealerships” “Planning of marketing communication strategies by car dealerships”
AUTHORS
Makgopa S. Sipho
ARTICLE INFO
Makgopa S. Sipho (2016). Planning of marketing communication strategies by
car dealerships. Problems and Perspectives in Management, 14(4-1), 212-220. doi:10.21511/ppm.14(4-1).2016.10
DOI
http://dx.doi.org/10.21511/ppm.14(4-1).2016.10
RELEASED ON
Friday, 23 December 2016
JOURNAL
"Problems and Perspectives in Management"
FOUNDER
LLC “Consulting Publishing Company “Business Perspectives”
NUMBER OF REFERENCES
0
NUMBER OF FIGURES
0
NUMBER OF TABLES
0
© The author(s) 2024. This publication is an open access article. AUTHORS
Makgopa S. Sipho
ARTICLE INFO
Makgopa S. Sipho (2016). Planning of marketing communication strategies by
car dealerships. Problems and Perspectives in Management, 14(4-1), 212-220. doi:10.21511/ppm.14(4-1).2016.10
DOI
http://dx.doi.org/10.21511/ppm.14(4-1).2016.10
RELEASED ON
Friday, 23 December 2016
JOURNAL
"Problems and Perspectives in Management"
FOUNDER
LLC “Consulting Publishing Company “Business Perspectives” © The author(s) 2024. This publication is an open access article. © The author(s) 2024. This publication is an open access article. businessperspectives.org Problems and Perspectives in Management, Volume 14, Issue 4, 2016 1. The purpose of the study The purpose of this research was to investigate the
planning marketing communication strategies and
campaigns in practice with more emphasis on mi-
cro-environmental factors of consideration. The
stated research purpose requires in-depth theoretical
background on micro-environmental factors, mar-
keting communications and its benefits of it thereof. This paper will start by explaining the concept of
marketing communications and followed by litera-
ture review of previous studies on the topic. Makgopa S. Sipho, 2016.
Makgopa S. Sipho, M.Phil., M.Com. and Ph.D. Student, Lecturer Busi-
ness Management, University of South Africa, South Africa. Abstract Effective marketing communication strategies and campaigns are of much importance in many organizations in in-
forming, reminding and persuading current and potential customers to support the organization by buying organiza-
tions product offerings. Organizations in planning of marketing communication strategies and campaigns, organiza-
tions in theory need to conduct micro-environmental analysis determining organizations’ strengths and weakness. The
purpose of this paper was to investigate the planning of marketing communication strategies and campaigns of car
dealerships in practice with more emphasis on micro-environmental factors of consideration. In achieving the purpose
of this paper, a qualitative research approach using semi-structured in-depth interviews with marketing personnel of
different car dealerships in Gauteng Province, South Africa was followed. In this paper a qualitative content analysis
was used to analyze primary data using Atlas ti version 7 computer software. The results revealed that there are key
micro-environmental factors of consideration during the planning of marketing communication strategies and cam-
paigns. Based on the results of this paper, the author provided recommendations to stakeholders in the motor vehicle
industry, specifically, car dealerships and future research directions. Keywords: marketing communications, marketing communication objectives, marketing communication strategy,
mediatypes, micro-environment. JEL Cl
ifi
ti
M31 Keywords: marketing communications, marketing communication objectives, marketing communication strategy,
mediatypes, micro-environment. JEL Classification: M31. JEL Classification: M31. The next section briefly outlines the purpose of this
study. Introduction Marketing communication as a marketing mix element
is one of the most difficult but crucially important
component of contemporary marketing. In recent years
this challenge has been made even more complicated
by the explosion of new digital media options. These
options offer new opportunities and hold much prom-
ise for marketers of organizations, but also bring great
difficulty to managerial decision making. To highlight
just a few of the benefits of marketing communica-
tions, marketers can choose to do some or all of the
following with their brands: To use marketing com-
munications to draw attention to their organizational
brands, marketers can reach consumers through mass
or targeted advertisements on social media networks
such as Facebook, Twitter, Youtube or other social
networks; banner or display advertisements on third-
party websites; and paid or search engine advertise-
ments. To shape brand preference, they can send time-
ly e-mails and use their own websites to provide de-
tailed content. To drive short-term sales, they can offer
promotions and other incentives through tweets, texts,
and targeted e-coupons. And to reinforce long-term
brand loyalty, they can form online brand communities
through their own or third-party social media. Given
so many different new and traditional communication
media options available to marketers of organizations
and so many different ways to combine these options,
Keller (2016) argued that marketers struggle with how
to make good marketingcommunication decisions. Therefore, it becomes imperative to investigate the
planning of marketing communication strategies and
campaigns
with
more
emphasis
on
micro-
environmental factors of consideration. 2. Theoretical background and literature review Despite the internal analysis of resources within the
micro-environment, the marketers need to consider
the organization’s overall objectives and mission to
ensure that these internal variables support each
other. This is backed by Arrey (2013) pointing that
in most organizations strategy decisions (including
marketing communication strategy decisions) are
guided by the organization’s mission and corporate
objectives. The marketing resources can be turned
into capabilities that can serve as strengths or weak-
nesses to an organization, and they need to be ana-
lyzed as a part of internal assessment or analysis
using the SWOT analysis tool. This micro-analysis
is, therefore, important in planning marketing com-
munication strategies and campaigns in practice. The next sub-section reviews previous studies on
marketing communications. 2.3. Previous studies on marketing communica-
tion. Many studies have explored the economic im-
pact of advertising on sales, and various other stud-
ies have examined the relationship between adver-
tising expenditure and its influenceon achieving the
marketing communication objectives. However, few
researchers have focused on planning of marketing
communication strategies in realising the marketing
communication objectives of organizations, specifi-
cally, micro-environmental analysis during the
planning stage. These studies have overlooked the
internal environmental factors of consideration that
during the planning marketing communication
strategies and campaigns of the organizations in
practice, specifically, car dealerships and they have
focused more on advertising such as (Buil, de Cher-
natony and Martínez, 2013; Feng and Purushottam,
2012; Singh, Sharma and Mahendru, 2011;
Ventoura-Neokosmidi, 2011). The next section focuses on marketing communica-
tion concept and its nature. 2.2. Marketing communications. Marketing
communication is a crucial part of the organiza-
tional activities of many organizations. Marketing
communication initiatives are aimed at informing,
reminding and persuading present and potential
customers to support the organization by purchas-
ing its products (Keller, 2009). Keller (2016) em-
phasized that marketing communications is a one
of the most difficult but crucially important com-
ponents of modern marketing. Keller (2016)
added marketing communications plays a crucial
role when organizations aim to influence con-
sumer decision-making, draw attention to organi-
zations’
brands,
and
shape
brand
preferences. Marketing communication is also an
important marketing tool which provides custom-
ers with information to help them make purchas-
ing decisions. The result of a successful market-
ing
communication
campaign
can
lead
to
sales growth, an increase in market share, and
subsequently to increased profitability (Ahn, Lee,
Lee and Paik, 2012). 2. Theoretical background and literature review In this section theoretical background and literature
review on marketing communication is provided,
focusing on micro-environmental analysis, the mar-
keting communication concept, components of mar-
keting communication mix, and conclude by re-
viewing previous studies on the topic. 2.1. Micro-environmental analysis. Performing the
situation analysis involves analysing the micro-
environment of the organization. The micro-
environment represents the internal environment of
the organization. When analysing the internal envi-
ronment, marketing managers need to analyze the
organization’s mission, business objectives and
strategies, its resources, skills and capabilities (Van
Schie, 2012). According to Van Schie (2012) mar-
keters should consider the organization’s targets or
goals, services to be provided and synergy to be ex-
ploited, as no single management is expected to
have all the talents and other qualities essential for
planning, direction and control. 212 Problems and Perspectives in Management, Volume 14, Issue 4, 2016 Organizations can establish what its strengths or
weaknesses are in terms of resources to be used dur-
ing the planning stage (Helms and Nixon, 2010). These strengths or weakness may be in the form of
resources, such as the skills and competencies of the
marketing personnel (Morgan, 2012). From the
marketing point of view, marketing resources refers
to resources available to marketers that can be
turned into marketing capabilities that can create
value to customers (Morgan, 2012). According to
Morgan (2012), the marketing resources within the
micro-environment that can be used to the advan-
tage of the organization include: tacit knowledge
resources, physical resources, human resources, or-
ganizational resources, informational resources, re-
lational resources, and legal resources. There are many elements of marketing communica-
tion at the marketers’ disposal; for example, advertis-
ing, direct marketing, personal selling, sales promo-
tions, public relations and sponsorships may all be
employed to maximize the impact of promotional
activities (Keller, 2016). Many different marketing
communications options exist that can play different
roles and have different objectives in the marketing
of a brand (Batra and Keller, 2016). One popular dis-
tinction made by many marketers and academic re-
searchers (e.g., Stephenand Galak, 2012) is between
communications which appear in paid media (tradi-
tional outlets such as TV, print, and direct mail),
owned media (company-controlled options such as
websites, blogs, mobile apps, and social media), and
earned media (virtual or realworld word of mouth,
press coverage). 2. Theoretical background and literature review Many studies have examined the efficiency of adver-
tising (Pergelova, Prior and Rialp, 2010; Crespo-
Cuaresma, 2012; Singh, Sharma and Mahendru,
2011). Pergelova, Prior and Rialp (2010) examined the
relationship between advertising spending and its effi-
ciency in achieving marketing communication objec-
tivesusing data obtained from the Spanish Association
of Manufacturers of Cars. Their results have shown
that an increase in advertising spending, whether for
off-line or online advertising, is highly efficient. Crespo-Cuaresma (2012) assessed the relationship
between marketing communication expenditure and
sales in the premium car segment in Germany. The
findings of this study revealed that an increase in
marketing communication expenditure, specifically
advertising spending, resulted in high sales. In India,
Singh, Sharma, and Mahendru (2011) used various 213 Problems and Perspectives in Management, Volume 14, Issue 4, 2016 Purushottam, 2012). However, the marketers are
accountable for marketing communication spending
and other marketing expenditures (Pergelova, Prior
and Rialp, 2010). This is backed by Raithel, Scharf,
Taylor, Schwaiger and Zimmerman (2011) in high-
lighting that marketers are under pressure to demon-
strate the financial return associated with marketing
expenditures. There is a pressure on marketers,
these marketers have been reducing their marketing
communication spending, specifically on advertis-
ing, and have been selecting other marketing com-
munication elements/approaches (Feng and Pu-
rushottam, 2012). This view is also shared by
Danenberg, Kennedy, Beal and Sharp (2016) in em-
phasising that deciding on and justifying the size of
marketing communication budget, specifically, ad-
vertising budgets is a common challenge that mar-
keters of organizations face. These views imply that
marketers of organizations should plan properly dur-
ing the planning stage of marketing communication
strategies and campaigns. models, including regression and econometric mod-
els, to find out the cause and effect relationship be-
tween advertisement expenditure and sales, and the
results showed that there is a positive relationship
between advertising expenditure and sales. In an-
other study, Ventoura–Neokosmidi (2011) investi-
gated the relationship between advertising to sales
ratio, market share and firm profitability was carried
out. Cross section analysis was used over 36 Greek
companies for the year 2002. This paper revealed
that market share has a positive impact on firm prof-
itability, and the influence of market share is greater
than that of advertising to sales ratio. In another
study, Buil et al. 2. Theoretical background and literature review (2013) highlighted that although
advertising has a role in building brand knowledge,
it has led to huge levels of marketing communica-
tion expenditure. In another study, Buil, de Chernatony and Leslie, E
(2010) explored the relationships between two market-
ing mix elements – advertising and sales promotions-
and brand equity creation. In particular, the study fo-
cuses on advertising from a quantitative (advertising
spending) and qualitative (general perceptions of ad-
vertising) perspective. Similarly, the study investigated
the effects of two kinds of sales promotions, i.e. mone-
tary and non-monetary promotions. Based on a survey
with 411 UK consumers, findings showed that the
content of advertising plays a key role influencing
brand equity dimensions, whereas advertising spend
improves brand awareness but with minimum positive-
ly influence brand associations. The paper also re-
vealed distinctive effects of monetary and nonmone-
tary promotions on brand equity. In addition the results
showed that organizations can optimise the brand equi-
ty management process by considering the relation-
ships existing between the different dimensions of
brand equity. The next section provides the contribution of this
study. 3. Contributions of the study In reviewing the secondary research available, it is
clear that the planning of marketing communication
strategies and campaigns is not widely covered in the
South African context and other parts of the world,
specifically in the car retail sector. This study contrib-
utes to literature on the topic. Furthermore, this study
further benefits car dealerships operating within the
motor
vehicle
industry
by
revealing
micro-
environmental factors considered in planning of the
marketing communication strategies and campaigns of
car dealerships in practice. This study will help mar-
keters make better marketing communication deci-
sions, more on decisions associated with paid and
owned media, as those are the areas over which mar-
keters have the most direct control and therefore are
responsible for making the most decisions. However, in a recent study, McAlister, Srinivasan,
Jindal and Cannella (2016) investigated the advertis-
ing influence on the organization value as a differ-
entiator. The results of this study uncovered that
advertising cannot be used to build brand equity for
a cost leader as such an organization has no point of
difference on which to build. Identifying differentia-
tors and cost leaders on the basis of firms’ reactions
to a change in accounting regulations, the results
revealed that advertising is related to sales for all
firms, but it is more strongly related to firm value
for differentiators than for cost leaders. The next section outlines the research methodology
followed to accomplish the research purpose of this
study starting with the research design, target popu-
lation, sampling frame and technique, data collec-
tion, and data analysis method used. 4. Research methodology Marketing personnel or executives of dealerships
were chosen as the unit of analysis considering their
involved in planning of marketing communication
strategies and campaigns. In this study, dealership
principals, dealership assistant managers and senior
sales managers of car dealerships were interviewed
since they were holders of the data needed to answer
the research questions. 4.5. Data collection. In-depth semi-structured inter-
views were used to collect the primary data in the
current study using audio recorder. The primary data
was collected using semi-structured in-depth inter-
views. According to Malhotra (2010) an in-depth in-
terview refers to an interaction between an individual
interviewer with a single participant, and the semi-
structured depth interviews allow the interviewer to
uncover underlying motivations and probe on a par-
ticular topic. The researcher used a research guide
containing research question topics during the inter-
views with participants. The researcher had to ar-
range a time and date most suitable for an interview
with participants. All participants were briefed tele-
phonically about the research objectives and the re-
search topic was emailed to the participants. This was
done to ensure that the researcher, as well as the par-
ticipants, was at ease, and prepared for the interview,
as well as to build rapport and relationship before the
data collection began. Before the interviews could
begin, the motivation for the research was explained
to the participant to put participants at ease. 4.3. Sample frame. In the current study, the Retail
Motor Industry (RMI) member list was used as a
sample frame to select accredited dealerships in-
cluded in the study. The dealerships operating with-
in the borders of Gauteng were contacted. Tustin et
al. (2005) indicated that the sample frame may be a
telephone directory, customer list, and research
company databases, a list of e-mails addresses or
even geographic maps. The researcher used Google,
which is a well-known search engine on the Internet
and search for list of accredited dealership in Gaut-
eng from Retail Motor Industry (RMI) organization
website (Retail Motor industry, 2014). RMI member
list contains the contact details of accredited dealer-
ships operating in nine provinces of South Africa. The researcher used the e-mail addresses and tele-
phone numbers obtained from RMI member list to
contact car dealerships to get contact details of mar-
keting personnel (involved in planning of marketing
communication strategies and campaigns). 4. Research methodology This section outlines the research methodology
followed to realize the research purpose of this
study starting with the research design, target
population, sampling frame and technique, data
collection, and data analysis method used. Despite the benefits that can be derived from mar-
keting communication elements and activities, mar-
keting communications such as advertising result in
increased marketing expenditure, where the largest
expense is usually incurred by marketing communi-
cations, more specifically, advertising (Feng and 4.1. Research design. An exploratory qualitative
approach was followed in order to address the research
objective. Malhotra (2010) pointed that an exploratory 214 Problems and Perspectives in Management, Volume 14, Issue 4, 2016 4.4. Sample technique. A purposive sampling
method was used in this study. Purposive sampling
method means that participants are selected because
of some defining characteristics that make them the
holders of the data needed for the study (Tustin et
al., 2005). The population can be defined as the total
group of persons or entities from whom information
is required (Tustin et al., 2005). The target popula-
tion refers to the collection of elements that possess
information sought by the researcher (Malhotra,
2010). A purposive sampling method was used in
order to concentrate on the participants, in this case
marketing personnel who possess the richest infor-
mation based on their positions in their respective
organizations, which presented a possibility to an-
swer research questions. research design is useful when the researcher requires
more information about a specific problem, an
opportunity or a phenomenon. The qualitative research
approach was chosen for a number of reasons:
participants’ perspectives and experiences were
emphasized, it took into account participants’
interpretation and it allows for flexibility. More
specifically, the aim of using a qualitative approach
was to collect data more effectively and to gain richer
information by enabling participants to also express
their opinions, and share their experiences with regard
to the online social media platforms used in conveying
marketing communication messages to their current
and potential customers. 4.2. Target population. The target population of
interest for the current study was the car dealerships
operating in Gauteng province. Gauteng province
was chosen due to its convenience and accessibility
for the researcher. In addition, one province was
selected, as the aim of the study was not to be
representative, but rather to enable other researchers
to
gain
understanding
into
the
marketing
communication practices of these dealerships. 5. Findings The
following
dimensions
of
the
micro-
environmental analysis were found to be of consid-
eration in planning the marketing communications
strategy of car dealerships, namely, the marketing
communication budget, the marketing communica-
tion objectives, the dealerships’ available products
and services offerings. According to Participant 9, the annual marketing
communication budget is divided up so that the bus-
iest months of the year get more budget allocation
which illustrates seasonal considerations. Participant 1 is cited below emphasising how the
budgeting according to percentage of sales method
is utilised by his dealership. The percentage-of-sales
method requires that the marketing communication
budget be determined by setting a specified percent-
age of the previous year’s sales or predicted future
sales. The following point is highlighted by this par-
ticipant: 5.1. Marketing communication budget. Partici-
pants identified the marketing communication
budget as a primary internal factor that is considered
in planning marketing communication strategies and
campaigns. The majority of the participants indi-
cated that it is necessary to ensure that the market-
ing communication budget is allocated in order to
support the attainment of the dealerships’ marketing
communication objectives. In addition, dealerships
use different marketing communication budgeting
methods. The budgeting methods pointed out by
participants include the percentage of sales, afforda-
bility and objective-and-task methods. “You should spend about 3% of your total sales-
budget on advertising. That’s how much money you
should be spending on advertising. So if you are
making or if your sales is R100 you should be
spending R3 on advertising, 3% of your total sales
turnover.”(P1) Despite the mentioned budgeting methods, Partici-
pant 9 highlighted that the marketing communica-
tion budget in his dealership is linked to specific
time periods each year during which the marketing
communication budget is allocated, using afforda-
bility budgeting method. The affordability budget
method involves the allocation of a certain amount
annually for marketing communication purposes
when the management determines its total budget. This budget method ignores the role of marketing
communication as an investment and it focuses on
short-term planning. Participant 9 said: Participant 10, on the other hand, explains how the
objective-and-task
marketing
communication
budget method is used by his dealership. This
method requires that marketers define specific
communication objectives, while determining the
promotional activities that must be performed to
achieve these objectives and then estimate the cost
of performing these tasks. 4. Research methodology Based on
the contact details provided by the dealership man-
agers or principals, other participants were con-
tacted via e-mails to request their consents to par-
ticipate and in-depth interviews were scheduled. 4.6. Data analysis. In the current study the use of
qualitative content analysis was followed, as it ide-
ally suited the purpose of this study, which aimed to
establish an understanding of the online social me-
dia tools used by car dealerships in their marketing
communication strategies and campaigns. In addi-
tion, Atlas ti version 10 computer software was used
to generate themes. During the data collection peri-
od, the transcriptions of the interviews were ana-
lyzed, to enable any decisions to be made relating to
what and how to probe for more detail during fur-
ther interviews. The trustworthiness or validity of
the qualitative data can be assessed by the care tak-
en and practices employed during the data collection
and analysis procedures. Following these tech-
niques, the length and depth of the interviews, as
well as the level and experience of the participants,
resulted in rich information discussions. 215 Problems and Perspectives in Management, Volume 14, Issue 4, 2016 “…then we have to sit down and say, where the bus-
iest months are allocated more budget those
months...” (P9) 5. Findings You can do flyers; make time that on such and such
a robot I’m going to be there just to give out these
flyers to get to know, to get people to know who we
are and what we are doing.”(P4). cific marketing communication objectives from target
audiences, which in turn, can lead to responses or
reactions from the target audiences. These marketing
communication objectives aim to convey messages
about the locations of the dealerships, available prod-
ucts on offer, brands and existence, and to convince
target audiences to visit these dealerships for further
information. Some participants also indicated that
their dealerships maintain continuous communication
with existing customers as a part of the marketing
communication retention strategy. According to Participant 4, in their dealership they
sometimes get leads, and in other instances they also
visit certain departments in companies to introduce
themselves. Participant 1 pointed out that in planning marketing
communication campaigns, the car dealership’s mar-
keting communication objective focuses on creating
an element of uniqueness that will differentiate the
dealerships from its competitors. Participant 1 said: Participant 10 emphasised that their dealership de-
velops marketing communication campaigns in or-
der to attract the target audiences to come and buy
their product and thus increase salesas the marketing
objective. He said: “the dealership’s obligation is to go out there and
differentiate my dealership from other dealerships. You can use xenon lights (motor vehicle/product
feature) to differentiate your dealership”(P1) “If I send out a short message campaign, I do ex-
pect to sell five or six cars for the week out of the
campaign. So it must be structured in a manner that
it attracts that kind of market that will be looking for
a particular vehicle model (mentioned vehicle
brand) (P10).” This implies that when dealerships convey a marketing
communication message, an element of uniqueness is
incorporated to distinguish their dealership from com-
petitors by using motor vehicle product features or
other economic factor such as interest rates to catch
target audiences’ attention. This view was also shared
by Participant 2 that their intention in developing mar-
keting communication campaigns is primarily aimed at
convincing the target audiences to visit their dealership
for further information rather than going to a competi-
tor. Their marketing message was based on low in-
stalment repayments as a distinctive factor to attract
target audiences. 5. Findings He says: According to Participant 10, when a particular mar-
keting communication campaign is developed as a
part of marketing communication strategy a certain
sales target is set. The quotes below are taken from Participant 2, 3, 5,
10 and 11 which relate to the generally mentioned
marketing communication objectives emphasising
creating awareness and getting inquiries and gener-
ating reactions from target audiences. These state-
ments are: “We’re getting that message across because it’s in
combination as I mentioned with instalments so you
can drive a top of the range vehicle for R8 500 a
month, so we’re pointing that out, our vehicle model
(mentioned vehicle model) for example, R5 000 a
month. But obviously that is the marketing side so
the customer needs to come in and we can explain
how you do it.”(P2) “You know, we tend to rather look at something that
creates awareness for the dealership. In other words,
we don’t go and advertise a product as such. So we
won’t go and advertise (mentioned vehicle model) or
one of our vehicles or a service. We want people to
know who we are and where we are.” (P11) “We go there basically to create awareness for the
business, (mentioned dealership name), what we
have”. (P5) Therefore, according to Participant 2, low instal-
ments repayments are used in their marketing com-
munication campaigns to attract customers to come
in for a personal selling opportunity. “It’s also for a reminder to also serve a purpose of
a reminder that we do exist.”(P3) “It’s also for a reminder to also serve a purpose of
a reminder that we do exist.”(P3) Participants 4 and 10 indicated that the marketing
communication objectives shouldsupport their re-
spective car dealerships’ overall marketing objectives
which aim for an increase in sales, to introduce the
dealerships and create awareness. Participant 4 indi-
cated that their target audiences are diverse, and as a
result, they use different promotional tools, such as
cold calling, flyers and telephone calls to convey the
marketing communication messages about their deal-
ership just to create awareness. He said: “To get the people to inquire about our products
and services”. (P2) “To get the people to inquire about our products
and services”. (P2) “Because it’s got to be directed to the target market
you want and it must create a reaction. I mean,
you’re looking at enhancing the bottom-line. 5. Findings He said: “You’re looking at the impact with the amount of
input; you’re going to put cash wise with the return
that you’ve got. Because it’s got to be directed to
the target market you want and it must create a re-
action. I mean, you’re looking at enhancing the bot-
tom-line. If I go out and spend money on behalf of
the shareholders, they expect a certain return. For
an example, if I send out a SMS campaign, I do ex-
pect to sell five or six cars for the week out of the
campaign. So it must be structured in a manner that
it attracts that kind of market that will be looking for
a particular vehicle model (mentioned vehicle
brand).”(P10). “They give you an x-amount of budgetto say basi-
cally you can use that kind of money per month, they
give
you
basically
R500
000,00
or
R600
000,00”.(P9) According to Participant 9, his dealership bases the
budget on the available budget which is limited to
between R500 000 or R600 000 for the development
of
marketing
communication
campaigns
throughout the year, and this illustrates the afforda-
bility
budgeting
method. Furthermore,
Participant 9 indicated that the marketing communi-
cation budget is allocated annually and is divided on
a
monthly
basis
as
and
when
a
specific
promotional need arises that needs to be addressed. This
further
confirms
the
usage
of
the
affordability budget method. Participant 9 alluded to
the fact that the allocation of budgets on
marketing communication campaigns is linked to
specific
time
periods
with
the
busiest
months of the year for getting more budget alloca-
tions. Participant 9 said: According to Participant 10, sales targets are set
when developing marketing communication cam-
paigns, in his case, five or six car sales per week are
expected from a short-messages (SMS) campaign. In addition, Participant 10 emphasised that each
marketing communication campaign aims to en-
hance the bottom-line as the shareholders’ money
spent on campaigns should bring a certain return. 5.2. Marketing communication objectives. In gen-
eral, the participants pointed out that they engage in
marketing communication campaigns to achieve spe- 216 Problems and Perspectives in Management, Volume 14, Issue 4, 2016 “We get different kind of customers and we get them
differently, sometimes by way of getting leads,
sometimes cold calling, it’s still cold calling going
out to a said department just to introduce yourself. Additional internal factor of consideration: Internal
stock levels Additional internal factor of consideration: Internal
stock levels Participants also revealed that the available prod-
ucts or stock levels impact on the marketing
communication objectives when developing mar-
keting communication campaigns. Participant 1
pointed out that the available stock levels serve as
a major indicator that determines whether sales
promotion campaigns involving special deals and
clearance sales can be planned and executed by
his dealership. He said: The participants further indicated that their dealer-
ships maintain continuous marketing communica-
tion contact with the existing customers in order to
establish and maintain a long-term relationship with
them. The participants indicated that it is important
for them to maintain and retain existing customers
to grow their businesses, and further, to try to pro-
vide added value to the customers. “If I for example have a build-up of stock of let’s
say I’ve got too many vehicles (mentioned vehicle
model) I will say let’s do a special deal on this vehi-
cle model (mentioned vehicle model) and let’s send
it out to our database, you know, something just to
clear my inventory problem or whatever.” (P1) Participant 4 pointed out that maintaining relation-
ships through continuous contact with the existing
clients is crucial as it enables the car dealerships to
monitor the changes in clients’ demographic charac-
teristics, such as their income, education level, and
profession. Participant 4 said: According to this participant their dealership’s sales
promotion campaigns are influenced by the internal
stock level. “You start with someone who say five years back I
sold a car which was worth R50 000. That guy was
earning maybe R5 000 studying at the same time,
but if you keep good contact with him you might find
that one day he is a professor or head of department
earning 15/20 times he used to earn five years back. You stand a good chance to can take him out of that
low priced car to an executive car. Customer, if you
retain your customers chances are you know from
time to time where they are.”(P4) Participant 3 added that sales promotion campaigns,
such as clearance sales, are often carried out in their
dealership towards the year-end in order to push
sales of older vehicle stock and further minimise the
depreciation costs. Participant 3 said: “We would have a clearance sale. Additional internal factor of consideration: Internal
stock levels Usually to-
wards year-end we would have a clearance sale,
getting rid of all the aging stock, because you
know every year the car depreciates so what we
try to do is to get rid of those cars before the
year-end and make sure that we do not carry a lot
of depreciation.” (P3) According to Participant 4, changes in the target
audience’s income level can present a good oppor-
tunity to promote a client out of a low-priced car
bracket to high-priced car. According to Participant 3 clearances sales are car-
ried out to get rid of aging stock and minimise de-
preciation cost. Participant 2 also shared the same sentiment as Par-
ticipant 4 that keeping existing customers is important
for the success of the business as is it easier to do deal
with customers you know. Participant 2 said: 5. Findings (P10) In summary, according to Participants 5 and 11, their
dealerships develop marketing communication cam-
paigns to create awareness about the existence of 217 Problems and Perspectives in Management, Volume 14, Issue 4, 2016 you want to go and start all over again with another
branch. You know, you don’t know anybody there. It’s always easier if you know somebody or have a
face or something behind the telephone. That is the
key I think to retain, to retention.” (P2) you want to go and start all over again with another
branch. You know, you don’t know anybody there. It’s always easier if you know somebody or have a
face or something behind the telephone. That is the
key I think to retain, to retention.” (P2) their dealerships. Participant 11 added that the objec-
tive is also to create awareness regarding their dealer-
ships’ location and advertising a particular vehicle
model. On the other hand, participant 3 stated that
their dealership develops marketing communication
campaigns to remind target audiences about their ex-
istence as a dealership. According to Participant 3,
their dealership develops marketing communication
campaigns with the objective to trigger target audi-
ences to inquire about their offerings. According to
Participant 10 their dealership develops marketing
communication campaigns with the objective to trig-
ger target audiences to react by buying their product
offerings, in his case, vehicle sales and thus enhanc-
ing the bottom-line (profitability). According to Participant 2, it is more difficult to
acquire new customers when compared to retaining
the existing customers as there is already an existing
relationship with them. Conclusions and discussions The research study sought to investigate the plan-
ning the marketing communication strategies and
campaigns of car dealerships with more emphasis
on micro-environmental factors of consideration. The results of this study indicated that during the
planning of marketing communication campaigns “The existing client is the key. If we can, we have
the saying if we can maintain and acquire new cus-
tomers and that is great but you must maintain your
existing database because that’s where it is. We
have a relationship with the people so they know
who we are. So it will be I think a little bit difficult if 218 Problems and Perspectives in Management, Volume 14, Issue 4, 2016 the available marketing communication budget,
and marketing communication objectives are of
much consideration. The participants pointed out
that the marketing communication budgetremains a
major consideration in planning marketing com-
munication strategies and campaigns of car dealer-
ships. Car dealerships plan different marketing
communication activities in efforts to achieve vari-
ous marketing communication objectives. These
marketing communication objectives include in-
creasing sales, creating awareness about the prod-
uct offerings and the dealerships’ locations. In ad-
dition, this study uncovered the marketers of car
dealerships use different marketing communication
budgets in planning marketing communication
strategies and campaigns. These findings of the
study on marketing communication budget as
part of marketing communication planning con-
cur with Keller (2016) indicating that marketing
communication is one of the difficult activity. However, the literature discussed does not indi-
cate that the existence of the relationship be-
tween marketing communication budget and
marketing objectives as revealed by the findings
of this study. The findings of the study with re-
gard to the considerations affecting the market-
ing communication objectives, that are derived
from the overall marketing objectives in plan-
ning marketing communications, is in line with
the view by Arrey (2014) that during the mar-
keting planning process it is vital to ensure that
the marketing objectives are guided by the or-
ganization’s corporate mission and objectives. This study further uncovered that the available in-
ternal stock levels are considered in planning mar-
keting communication campaigns. This findings
offers insight as it reveals the reasons which trigger
the
planning
of
marketing
communication the available marketing communication budget,
and marketing communication objectives are of
much consideration. Conclusions and discussions The participants pointed out
that the marketing communication budgetremains a
major consideration in planning marketing com-
munication strategies and campaigns of car dealer-
ships. Car dealerships plan different marketing
communication activities in efforts to achieve vari-
ous marketing communication objectives. These
marketing communication objectives include in-
creasing sales, creating awareness about the prod-
uct offerings and the dealerships’ locations. In ad-
dition, this study uncovered the marketers of car
dealerships use different marketing communication
budgets in planning marketing communication
strategies and campaigns. These findings of the
study on marketing communication budget as
part of marketing communication planning con-
cur with Keller (2016) indicating that marketing
communication is one of the difficult activity. However, the literature discussed does not indi-
cate that the existence of the relationship be-
tween marketing communication budget and
marketing objectives as revealed by the findings
of this study. The findings of the study with re-
gard to the considerations affecting the market-
ing communication objectives, that are derived
from the overall marketing objectives in plan-
ning marketing communications, is in line with
the view by Arrey (2014) that during the mar-
keting planning process it is vital to ensure that
the marketing objectives are guided by the or-
ganization’s corporate mission and objectives. This study further uncovered that the available in-
ternal stock levels are considered in planning mar-
keting communication campaigns. This findings
offers insight as it reveals the reasons which trigger
the
planning
of
marketing
communication campaigns such as clearance sales which are car-
ried-out by car dealerships in attempt to reduce
depreciation costs. Recommendations Marketers of car dealerships should consider the
seasons of the year, marketing communication ob-
jectives and available marketing communication
budget when planning marketing communication
strategies and campaigns in order to guide alloca-
tion of budget, and allocate more budget to busiest
seasons. In addition, marketers should consider
their internal stock in order to identify which prod-
ucts and old stock (in this case car models) that
should be part of sales promotion campaign such as
clearance sales, or alternately identify products that
must be market aggressively in marketing commu-
nication campaigns. 1. Ahn, J., Lee, C., Lee, J. and Paik, M. (2012). An analysis of different types of advertising media and their influ-
ence on consumer preferences and purchase intentions for digital cameras, Journal of Global Scholars of Market-
ing Science, 22 (4), pp. 356-369. p
pp
9. Feng, J. and Purushottam, P. (2012). Is Online Word of Mouth Higher for New Models or Redesigns? An Investi-
gation of the Automobile Industry. Journal of Interactive Marketing, 26, pp. 92-101. Directions for future research This study explored micro-environmental factors
of consideration in planning marketing communi-
cation strategies and campaigns. Therefore, it is
recommended that a future study could be con-
ducted to explore further on how micro-
environmental factors’ influence on the decision
related to the selection of traditional and new me-
dia types used in marketing communication strate-
gies and campaigns of car dealerships in practice. In addition, future research study could investigate
market and macro-environmental factors of con-
sideration in planning marketing communication
strategies and campaigns of car dealerships in real
scenario. Furthermore, a study focusing on all en-
vironmental factors, namely: micro, market and
macro-environmental factors at car manufacturer
level could result with different findings. y
8. Danenberg, N., Kennedy, R., Beal, V. and Sharp, B. (2016). Advertising Budgeting: A Reinvestigation of the Evi-
dence on Brand Size and Spend, Journal of Advertising, 45(1), pp. 139-146. 4. Buil, I., de Chernatony, L., and Martínez, E. (2013). Examining the role of advertising and sales promotions in
brand equity creation. Journal of Business Research, 66(1):115–122. 3. Batra, R. and Keller, K.L. (2016). Integrating Marketing Communications: New Findings, New Lessons and New
Ideas, Journal of Marketing. q
y
g
g
f
(p
)
6. Crespo Cuaresma, J. and Stöckl, M. (2012). The Effect of Marketing Spending on Sales in the Pre
ment: New Evidence from Germany, 2012-2. University of Salzburg. f
y
y
g
7. Cuaresma, J.C. and Stoeckl, M. (2012). The effect of marketing spending on sales in the premium car segment:
New evidence from Germany. g
pp
2. Arrey, O.B. (2014). Corporate Marketing Planning. Global Journal of Management And Business Research,
13(10). q
y
f
( )
B., de Chernatony, L. and Leslie, E. (2010). February. The Effect of Advertising and Sales Promotions o
Equity. In The 6th Thought Leaders in Brand Management International Conference (p. 14). 5. Buil, I.B., de Chernatony, L. and Leslie, E. (2010). February. The Effect of Advertising and Sales Promotions on
Brand Equity. In The 6th Thought Leaders in Brand Management International Conference (p. 14).
6
C
C
J
d S ö kl M (2012) Th Eff
f M
k i
S
di
S l
i
h P
i
C
S References 1. Ahn, J., Lee, C., Lee, J. and Paik, M. (2012). An analysis of different types of advertising media and their influ-
ence on consumer preferences and purchase intentions for digital cameras, Journal of Global Scholars of Market-
ing Science, 22 (4), pp. 356-369. g
,
( ), pp
2. Arrey, O.B. (2014). Corporate Marketing Planning. Global Journal of Management And Business Research,
13(10). 3. Batra, R. and Keller, K.L. (2016). Integrating Marketing Communications: New Findings, New Lessons and New
Ideas, Journal of Marketing. 4. Buil, I., de Chernatony, L., and Martínez, E. (2013). Examining the role of advertising and sales promotions in
brand equity creation. Journal of Business Research, 66(1):115–122. p
f
g
pp
9. Feng, J. and Purushottam, P. (2012). Is Online Word of Mouth Higher for New Models or Redesigns? An Investi-
gation of the Automobile Industry. Journal of Interactive Marketing, 26, pp. 92-101. 219 Problems and Perspectives in Management, Volume 14, Issue 4, 2016 10. Helms, M.M., & Nixon, J. (2010). Exploring SWOT analysis – Where are we now? A review of academic re-
search from the last decade. Journal of Strategy and Management, 3(3), pp. 215-251. 11. Keller, K.L. (2016). Unlocking the Power of Integrated Marketin
Program? Journal of Advertising, 45 (3), pp. 286-301. 11. Keller, K.L. (2016). Unlocking the Power of Integrated Marketing Communications: How Integrated Is Your IMC
Program? Journal of Advertising, 45 (3), pp. 286-301. h K.L. (2016). Unlocking the Power of Integrated Marketing Communications: How Integrated Is Your IM
? Journal of Advertising, 45 (3), pp. 286-301. g
f
g
pp
12. Malhotra, N.K. (2010). Marketing research: an applied orientation. 6th global ed. Upper Saddle River, N 13. McAlister, L., Srinivasan, R., Jindal, N. and Cannella, A.A.(2016). Advertising Effectiveness: The Moderating
Effect of Firm Strategy. Journal of Marketing Research, 53(2), pp. 207-224. gy
f
g
pp
14. Morgan, N.A. (2012). Marketing and business performance. Journal of the Academy of Marketing Science, 40(1),
pp. 102-119. 15. Pergelova, A., Prior, D., and Rialp, J. (2010). Assessing advertising efficiency. Journal of Advertising, 39(3),
pp. 39-54. 16. Raithel, S., Scharf, S., Taylor, C. R., Schwaiger, M., and Zimmermann, L. (2011). Marketing Accountability: Ap-
plying Data Envelopment Analysis to Assess the Impact of Advertising Efficiency on Shareholder Value. Advanc-
es in International Marketing, 22, pp. 115-139. pp
17. Raithel, S., Scharf, S., Taylor, C.R., Schwaiger, M. and Zimmermann, L. (2011). References Marketing Accountability: Ap-
plying Data Envelopment Analysis to Assess the Impact of Advertising Efficiency on Shareholder Value, Advanc-
es in International Marketing, 22, pp. 115-139. g,
, pp
18. Sharma, G.D., Mahendru, M. and Singh, S. (2011). Advertisement Cause Sales or Sales Cause Advertisement: A
Case of Indian Manufacturing Companies. g
p
19. Sharma, S., & Sharma, J. (2009). Sales and Advertisement Relationship for Selected Companies Operating in In-
dia: A Panel Data Analysis. School of Doctoral Studies European Union, 83. 20. Stephen, A.T. and Galak, J. (2012), “The Effects of Traditional and Social Earned Media on Sales: A Study of a
Microlending Marketplace,” Journal of Marketing Research, 49 (5), pp. 624-39. 21. Tustin, Ligthelm, Martins & Van Wyk. (2005). Marketing research in practice. 1st ed. South Africa, University of
South Africa: Unisa Press. 22. Van Schie, W. (2012). The proposed short term marketing strategy for Audi South Africa focusing
and after sales (Doctoral thesis). W. (2012). The proposed short term marketing strategy for Audi South Africa focusing on distribution
les (Doctoral thesis). 23. Ventoura-Neokosmidi, Z. (2011). Advertising, Market Share, And Profitability In The Greek Consumer
Industry. Journal of Business & Economics Research (JBER), 3(9). 220
|
https://openalex.org/W3030111795
|
https://cardiooncologyjournal.biomedcentral.com/track/pdf/10.1186/s40959-020-00060-0
|
English
| null |
Evaluating anthracycline cardiotoxicity associated single nucleotide polymorphisms in a paediatric cohort with early onset cardiomyopathy
|
Cardio-oncology
| 2,020
|
cc-by
| 5,419
|
© The Author(s). 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License,
which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give
appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if
changes were made. The images or other third party material in this article are included in the article's Creative Commons
licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons
licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain
permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the
data made available in this article, unless otherwise stated in a credit line to the data. McOwan et al. Cardio-Oncology (2020) 6:5
https://doi.org/10.1186/s40959-020-00060-0 McOwan et al. Cardio-Oncology (2020) 6:5
https://doi.org/10.1186/s40959-020-00060-0 Evaluating anthracycline cardiotoxicity
associated single nucleotide
polymorphisms in a paediatric cohort with
early onset cardiomyopathy Timothy N. McOwan1,2†, Lauren A. Craig1†, Anne Tripdayonis1, Kathy Karavendzas1, Michael M. Cheung1,2,
Enzo R. Porrello1,3, Rachel Conyers1,2* and David A. Elliott1,2,4* Timothy N. McOwan1,2†, Lauren A. Craig1†, Anne Tripdayonis1, Kathy Karavendzas1, Michael M. Cheung1,2,
Enzo R. Porrello1,3, Rachel Conyers1,2* and David A. Elliott1,2,4* Enzo R. Porrello1,3, Rachel Conyers1,2* and David A. Elliott1,2,4* Abstract Background: Anthracyclines are a mainstay of chemotherapy. However, a relatively frequent adverse outcome of
anthracycline treatment is cardiomyopathy. Multiple genetic studies have begun to dissect the complex genetics
underlying cardiac sensitivity to the anthracycline drug class. A number of single nucleotide polymorphisms (SNPs)
have been identified to be in linkage disequilibrium with anthracycline induced cardiotoxicity in paediatric
populations. Methods: Here we screened for the presence of SNPs resulting in a missense coding change in a cohort of
children with early onset chemotherapy related cardiomyopathy. The SNP identity was evaluated by Sanger
sequencing of PCR amplicons from genomic DNA of patients with anthracycline related cardiac dysfunction. Results: All of the published SNPs were observed within our patient group. There was no correlation between the
number of missense variants an individual carried with severity of disease. Furthermore, the time to cardiac disease
onset post-treatment was not greater in those individuals carrying a high load of SNPs resulting from missense variants. Conclusions: We conclude that previously identified missense SNPs are present within a paediatric cohort with early
onset heart damage induced by anthracyclines. However, these SNPs require further replication cohorts and functional
validation before being deployed to assess anthracycline cardiotoxicity risk in the clinic. Keywords: Anthracycline induced cardiomyopathy, Genetic variants, Paediatric cancers Background rates and greater life expectancy than ever before [3, 4]. Con-
sequently, the proportion of paediatric cancer patients who
survive long enough to develop chemotherapy-related heart
damage is on the rise [5, 6]. Hence, late cardiovascular side-
effects, and their clinical implications are becoming an in-
creasingly relevant area of research. Anthracyclines exhibit proven efficacy as an anti-neoplastic
agent but are associated with significant adverse outcomes,
particularly cardiotoxicity [1, 2]. Importantly, the 5-year sur-
vival rate for paediatric cancer patients now exceeds 80%,
meaning these populations are experiencing higher survival Anthracycline cardiotoxicity (ACT) leads to cardio-
myocyte damage, ventricular wall thinning and ultim-
ately manifests as a dilated cardiomyopathy [7]. The
onset of ACT can be either acute or chronic, and can be
clinically appreciable, or subclinical in its presentation. * Correspondence: rachel.conyers@mcri.edu.au; david.elliott@mcri.edu.au
†Tim McOwan and Lauren Craig contributed equally to this work. 1Murdoch Children’s Research Institute, The Royal Children’s Hospital,
Flemington Road, Parkville, Victoria 3052, Australia
Full list of author information is available at the end of the article * Correspondence: rachel.conyers@mcri.edu.au; david.elliott@mcri.edu.au
†Tim McOwan and Lauren Craig contributed equally to this work. 1Murdoch Children’s Research Institute, The Royal Children’s Hospital,
Flemington Road, Parkville, Victoria 3052, Australia
Full list of author information is available at the end of the article © The Author(s). 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License,
which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give
appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if
changes were made. The images or other third party material in this article are included in the article's Creative Commons
licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons
licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain
permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the
data made available in this article, unless otherwise stated in a credit line to the data. McOwan et al. Cardio-Oncology (2020) 6:5 Page 2 of 6 McOwan et al. Cardio-Oncology (2020) 6:5 Acute ACT occurs within a week of commencing treat-
ment and occurs in less than 1% of patients [8]. Con-
versely, chronic ACT is more frequent and develops
over an extended period of time in the months to years
following treatment [9–11]. Symptomatic ACT is usually
defined as congestive cardiac failure, whereas patients
with subclinical cardiotoxicity remain asymptomatic. Symptoms and signs of congestive cardiac failure include
pulmonary or peripheral oedema, dyspnoea and exercise
intolerance [12]. Large cohort studies have found that
symptomatic ACT occurs in 1.7–9.8% of childhood can-
cer survivors [12, 13]. However, the prevalence of sub-
clinical ACT is less certain, and has been reported to
occur in 0 to 57% of childhood cancer survivors [14]. The vast disparity in prevalence is partly due to incon-
sistencies in study populations, particularly varied dose
and diagnoses, and is complicated by variability in clin-
ician judgment and assessment criteria. The most widely
used criteria for assessing left ventricular subclinical car-
diotoxicity is echocardiography, particularly fractional
shortening (FS) and ejection fraction (EF). These mea-
sures are dependent on preload, afterload and contractil-
ity and are a measure of systolic function. Our group recently conducted a retrospective analysis
of 481 childhood cancer survivors treated at two tertiary
paediatric hospitals. Of the eligible 286 patients, 20
(7.0%) were classified as having severe ACT with FS <
24%. We sought to analyse the frequency of SNPs that
have been previously associated with cardiotoxicity in
this subset of patients. DNA from this cohort was se-
quenced, and analyzed for the presence of these SNPs. Their frequencies were then contrasted with that of the
general population, with the view to further characterize
the risk of ACT in this subset of patients with severe
cardiotoxicity. Patient cohort This retrospective cohort has been previously reported
by our group [32]. The study identified 481 patients
from the Haematology-Oncology registry at the Royal
Children’s Hospital and Monash Medical Centre, Mel-
bourne, Australia. Patients were eligible to enter the
study if they were diagnosed with paediatric cancer be-
tween January 2008 and December 2015. Eligibility cri-
teria included a paediatric cancer diagnosis, exposure to
anthracycline chemotherapy and at least one echocardio-
gram
performed
to
assess
cardiac
function
post-
chemotherapy. Exclusion criteria included a diagnosis of
congenital heart disease. Due to the potential for con-
founding by acute transient cardiotoxicity, [33] only
echocardiograms recorded greater than 17 days after
commencing anthracycline therapy were included. Eli-
gible participants were screened for ACT as measured
by echocardiogram, specifically fractional shortening and
left ventricular ejection fraction (LVEF) using the bi-
plane Simpson’s method. Echocardiogram findings were
rated as normal (FS > 28% and without a 10% decline in
LVEF from baseline), intermediate (FS 24–28% or a drop
in baseline LVEF of > 10%) or severe (FS ≤24%). Blood
samples were taken and stored for DNA extraction. The
total cumulative dose for each patient was determined
using doxorubicin equivalents [34]. Ethics approval was
given by the institutional review board (HREC25102D). y
y
ACT has been associated with a cardiac mortality of
6%, as was found in a 5-year survivorship study of pa-
tients diagnosed between the ages of 15 and 39 [15]. Consequently,
there
is
a
significant
incentive
to
characterize the risk profile of cancer patients undergo-
ing anthracycline therapy, so as to better guide thera-
peutic decision-making. So far, proposed predictors
include but are not limited to; sex, age at diagnosis, and
radiation exposure. Consensus is lacking as to their con-
tribution, if any, to the development of ACT. However,
it is generally accepted that cumulative anthracycline
dose is the single biggest independent risk factor for
ACT [7, 12, 14, 16–19]. As such, the Children’s Oncol-
ogy Group guidelines for paediatric treatment recom-
mend
limiting
doses
to
450 mg/m2
[20]. Further
evaluation of patient risk factors has failed to provide a
clear consensus regarding clinical characteristics predict-
ing ACT risk. Without knowledge of individual risk, the
burden rests on patients, with life-long cardiac monitor-
ing being required. Results Twenty (20) patients were identified with severe ACT
with a fractional shortening < 24% [32]. Of these fifteen
consented to genetic analysis to assess the number of
anthracycline cardiotoxicity associated SNPs (Table 1). The mean age of these severe ACT patients was 6.2
years at the time of survey with a range of 0 to 17
years (Supplementary Table 2). The mean cumulative
anthracycline dose was 211.2 mg/m2 (51–435 mg/m2). Females are represented disproportionately in this co-
hort (10 females vs 5 males) (Supplementary Table 2). The distribution of clinical diagnoses is representative
of reported frequencies in the paediatric population. Acute lymphoblastic leukaemia (6) and acute myeloid
leukaemia (3) were the most common cancers, with a
further two each of Wilms Tumour and Ewings Sar-
coma and a single individual with Non-Hodgkin’s
Lymphoma. Patients
received
the
anthracyclines
daunorubicin, doxorubicin, mitoxantrone and idarubi-
cin (Table 1). While the mean time in days from
baseline to the first abnormal echocardiogram was
394 days, the range was 17 to 1805 days with a me-
dian of 145 days (Table 1). Three of the patients had
a significantly delayed time to detection of cardiac
systolic dysfunction of greater than 1000 days. Patients
4, 9 and 12 had delay of 1343, 1805 and 1151 days Patients with severe ACT were then tested for the
presence of eight previously-reported missense variants,
Table 2. All of these variants were found in at least one
patient, however, none were found in all patients. Vari-
ants in ETFB, ABCC2, GPR35 and RARG were reported
as heterozygous variants, while CYBA, NOS3 and CBR3
were reported as both homozygous and heterozygous
variants. The highest burden of variants in a single pa-
tient was 7, in a combination of both homozygous and
heterozygous variants. One patient reported none of the
eight-missense variants screened. The variant burden in
our cohort of patients with severe ACT ranged from 0
to 7. DNA sequencing
DNA
i DNA sequencing
DNA extraction was performed using QIAgility™(Qia-
gen™, Cat #9001532) and QIAmp 96 DNA QIAcube HT
kit (Qiagen™, Cat #51331). Primers for PCR amplification
and sequencing were designed using Primer-BLAST™
from the National Centre for Biotechnology Information
(NCBI). Primers are listed in Supplementary Table 1
(Sigma, Castle Hill,
Australia) and amplified using
GoTaq® (Promega™, Cat #M30001). DNA products were
treated with ExoProStar™(GE Healthcare Life Sciences,
GEHEUS77705). Sequencing was performed by the Aus-
tralian Genome Research Facility (AGRF) by Sanger Nevertheless, personalized follow-up guidelines for
cancer survivors are becoming ever more tangible as we
enter a forthcoming era of pharmacogenetic-guided
treatment. Moving forward, it is hoped we will identify
genetic variants that ascribe higher risk for developing
ACT, and thus facilitate more effective, individualized
risk stratification for paediatric cancer patients. To this
end, genetic analysis of large cohorts of cancer patients
treated with anthracyclines have verified the existence of
many single nucleotide polymorphisms (SNPs) that are
associated with the development of ACT [21–31]. Page 3 of 6 McOwan et al. Cardio-Oncology (2020) 6:5 Page 3 of 6 McOwan et al. Cardio-Oncology respectively to first abnormal echocardiogram. Excluding
this ‘late-onset’ subset, the average days from baseline to
the first abnormal echocardiogram was 134 days. sequencing using the amplification primers. Primers and
PCR conditions are presented in supplementary methods. Homozygous sequences were confirmed by sub-cloning
PCR amplicons into pGEM®-T Easy vector system (Pro-
mega, A137A) and sequenced using M13 forward. Previously
identified
SNPs
associated
with
anthracycline-induced cardiotoxicity are summarised in
Supplementary Table 3. These variants are distributed
between missense, synonymous, intronic, and upstream
and downstream of associated genes. The frequency of
each variant in the 1000 Genomes (1KGP) and Genomes
Aggregate (gnomAD) databases is presented. These fre-
quencies range from 4 to 82%. Several of these genes
have been previously identified in association with other
diseases [35, 36]. Of the variants previously identified,
missense variants are reported in eight genes. These
eight genes were the focus of our study, as they were
considered most likely to directly affect the mechanism
of cardiotoxicity. The frequency of these genetic variants
in our cohort was compared to the global frequencies re-
ported in the 1000 Genomes Project. a Daun daunorubicin; Dox doxorubin; Mitox mitroxantrone; Ida Idarubicin. b most abnormal record of fractional shortening. c echo ech doxorubin; Mitox mitroxantrone; Ida Idarubicin. b most abnormal record of fractional shortening. c echo echocardiography Results While this is an observational study evaluating the nthracycline dosage, time to first diagnosis and fractional shortening percentage Table 1 Individual patient anthracycline dosage, time to first diagnosis and fractional shortening percentage
a
b Table 1 Individual patient anthracycline dosage, time to first diagnosis and fractional shortening percentage
Individual
Druga
Cumulative Dose
(mg/m2)
FS %b
Time (days) to initial abnormal echo.c
1
Daun
435
14
276
2
Daun, Mitox
410
23.3
145
3
Dox
356
22.9
267
4
Daun, Dox
325
6
1343
5
Dox
260
23.9
81
6
Dox
255
23.1
64
7
Daun
204
19.7
71
8
Daun
200
21.5
26
9
Daun, Dox
178
23
1805
10
Daun, Dox
175
23.5
253
11
Daun, Ida
161
23.9
17
12
Daun, Dox
147
20.5
1151
13
Daun, Dox
136
19.9
88
14
Dox
72
23.3
214
15
Dox
51
23.9
106
a Daun daunorubicin; Dox doxorubin; Mitox mitroxantrone; Ida Idarubicin. b most abnormal record of fractional shortening. c echo echocardiography Page 4 of 6 McOwan et al. Cardio-Oncology (2020) 6:5 McOwan et al. Cardio-Oncology Table 2 Presence and zygosity status of anthracycline cardiotoxicity associated SNPs in patients with cardiotoxicity
NOS3
ETFB
CBR3
ABCC2 1
ABCC2 2
RARG
GRP35
CYBA
rs1799983
rs79338777
rs1056892
rs17222723
rs8187710
rs2229774
rs12468485
rs4673
Patient
1
Hetb
2
Het
Hom
Het
Het
3
Homa
Het
Het
4
Hom
Het
Het
Het
Het
Het
Het
5
Het
Het
Het
Het
Het
6
Het
Hom
Het
Hom
7
8
Het
Hom
9
Hom
Hom
Het
10
Hom
Het
Het
Het
Het
11
Hom
Het
Het
12
Hom
Het
Het
13
Hom
Hom
Het
Hom
14
Hom
Het
Het
Het
Het
15
Het
a Het heterozygous; b Hom homozygous 2 Presence and zygosity status of anthracycline cardiotoxicity associated SNPs in patients with cardiotoxicity a Het heterozygous; b Hom homozygous data suggest that, at present these variants cannot accur-
ately predict cardiac sensitivity to anthracycline. reported SNPs in a small cohort of children treated with
anthracycline the frequency of the variants observed is
broadly in line with the known frequency of these SNPs
in the general population (Table 3). Total cumulative
dose of anthracycline given did not correlate with the
number of variants reported. Similarly, the number of
variants each patient carries did not relate to the time
from baseline to first abnormal echocardiogram or the
most abnormal FS. Results reported SNPs in a small cohort of children treated with
anthracycline the frequency of the variants observed is
broadly in line with the known frequency of these SNPs
in the general population (Table 3). Total cumulative
dose of anthracycline given did not correlate with the
number of variants reported. Similarly, the number of
variants each patient carries did not relate to the time
from baseline to first abnormal echocardiogram or the
most abnormal FS. We
focussed
on
the
previously
reported
non-
synonomous variants associated with ACT, reasoning
that these protein changes were most likely to directly
alter anthracycline pharmacodynamics, thus contributing
to cardiotoxicity [37].. A total of 15 genes have been as-
sociated with a genetic predisposition to anthracycline
cardiomyopathy
[21–27,
30,
38–40]. We
excluded
screening for variants in non-coding sequences or those
that encoded a synonymous amino acid change, focus-
sing on variants which modified the amino acid se-
quence
of
a
given
protein. For
example,
RARG
rs2229774 (RARGc.1280C > T; p.S427L) was significantly
associated with ACT in a cohort of 280 European Can-
adian patients (32 ACT cases and 248 controls) and a
replication cohort of 96 European Dutch (22 cases and
74 controls) [21]. In an attempt to validate these associa-
tions in the setting of early onset severe ACT, our study
identified that 14 out of 15 patients had at least one of
the missense variants associated with cardiotoxicity to Supplementary information
l
f pp
y
Supplementary information accompanies this paper at https://doi.org/10. 1186/s40959-020-00060-0. y
Supplementary information accompanies this paper at https://doi.org/10. 1186/s40959-020-00060-0. y
Supplementary information accompanies this paper at https://doi.org/10. 1186/s40959-020-00060-0. Supplementary information a
1186/s40959-020-00060-0 Supplementary information
1186/s40959-020-00060-0. Received: 1 March 2020 Accepted: 29 April 2020 Received: 1 March 2020 Accepted: 29 April 2020 Additional file 1: Table S1. Primers amplifying DNA including the
identified SNP for identification of previously identified missense variants
associated with anthracycline cardiotoxicity. Table S2. Sex, age at
diagnosis and tumour type of study cohort*. Table S3. Published single
nucleotide polymorphisms (SNPs) associated with anthracycline-induced
cardiotoxicity Conclusion All authors consent for publication. While previously published missense variants are found
within our ACT cohort, further functional validation is
required to determine the pathogenic mechanism under-
lying ACT in individuals carrying these variants. The
clinical utility of these variants as predictors of anthracy-
cline cardiotoxicity requires detailed studies in much lar-
ger cohorts of paediatric cancer survivors. Abbreviations
SNP S
l 4. Howlader N, Noone AM, Krapcho M, Miller D, Brest A, Yu M, Ruhl J,
Tatalovich Z, Mariotto A, Lewis DR et al: SEER Cancer Statistics Review,
1975–2016. In. Edited by Institute. NC. Bethesda, MD: NIH; 2019. SNP: Single nucleotide polymorphism; ACT: Anthracycline induced
cardiotoxicity; LVEF: Left ventricular ejection fraction; FS: Fractional
shortening 5. Armstrong GT, Kawashima T, Leisenring W, Stratton K, Stovall M, Hudson
MM, Sklar CA, Robison LL, Oeffinger KC. Aging and risk of severe, disabling,
life-threatening, and fatal events in the childhood cancer survivor study. J
Clin Oncol. 2014;32(12):1218–27. References 1. Bonadonna G, Monfardini S. Cardiac toxicity of daunorubicin. Lancet
(London, England). 1969;1(7599):837. 1. Bonadonna G, Monfardini S. Cardiac toxicity of daunorubicin. Lancet
(London, England). 1969;1(7599):837. 1. Bonadonna G, Monfardini S. Cardiac toxicity of daunorubicin. Lancet
(London, England). 1969;1(7599):837. 2. Von Hoff DD, Layard MW, Basa P, Davis HL Jr, Von Hoff AL, Rozencweig M,
Muggia FM. Risk factors for doxorubicin-induced congestive heart failure. Ann Intern Med. 1979;91(5):710–7. 3. Robison LL, Hudson MM. Survivors of childhood and adolescent cancer: life-
long risks and responsibilities. Nat Rev Cancer. 2014;14(1):61–70. Competing interests
Th
h
h The authors have no competing interests to declare. Consent for publication Consent for publication
All authors consent for publication. Acknowledgments This work was supported by the Children’s Cancer Foundation, My Room,
The Royal Children’s Hospital Foundation (RC, DAE, ERP). Coded data were
supplied by the Children’s Cancer Centre Tissue Bank at the Murdoch
Children’s Research Institute and The Royal Children’s Hospital. The Children’s
Cancer Centre Tissue Bank is made possible through generous support by
Cancer In Kids @ RCH (www.cika.org.au), The Royal Children’s Hospital
Foundation and the Murdoch Children’s Research Institute. Supported by the
Victorian Government’s Operational Infrastructure Support Program and
Australian Government National Health and Medical Research Council
Independent Research Institute Infrastructure Support Scheme (NHMRC
IRIISS). Research in the laboratories of DAE and EP was supported by the
NHMRC, the Australian Research Council Strategic Initiative in Stem Cell
Science (SR110001002) and the Stafford Fox Medical Research Foundation. 6. Hudson MM, Ness KK, Gurney JG, Mulrooney DA, Chemaitilly W, Krull KR,
Green DM, Armstrong GT, Nottage KA, Jones KE, et al. Clinical ascertainment
of health outcomes among adults treated for childhood cancer. Jama. 2013;
309(22):2371–81. 7. Lipshultz SE, Lipsitz SR, Sallan SE, Dalton VM, Mone SM, Gelber RD, Colan SD. Chronic progressive cardiac dysfunction years after doxorubicin therapy for
childhood acute lymphoblastic leukemia. J Clin Oncol. 2005;23(12):2629–36. 7. Lipshultz SE, Lipsitz SR, Sallan SE, Dalton VM, Mone SM, Gelber RD, Colan SD. Chronic progressive cardiac dysfunction years after doxorubicin therapy for
childhood acute lymphoblastic leukemia. J Clin Oncol. 2005;23(12):2629–36. p
,
p
,
,
,
,
,
Chronic progressive cardiac dysfunction years after doxorubicin therapy for
childhood acute lymphoblastic leukemia. J Clin Oncol. 2005;23(12):2629–36. 8. Barry E, Alvarez JA, Scully RE, Miller TL, Lipshultz SE. Anthracycline-induced
cardiotoxicity: course, pathophysiology, prevention and management. Expert Opin Pharmacother. 2007;8(8):1039–58. 9. Lipshultz SE, Alvarez JA, Scully RE. Anthracycline associated cardiotoxicity in
survivors of childhood cancer Heart 2008;94(4):525–33 8. Barry E, Alvarez JA, Scully RE, Miller TL, Lipshultz SE. Anthracycline-induced
cardiotoxicity: course, pathophysiology, prevention and management. Expert Opin Pharmacother. 2007;8(8):1039–58. 9. Lipshultz SE, Alvarez JA, Scully RE. Anthracycline associated cardiotoxicity in
survivors of childhood cancer. Heart. 2008;94(4):525–33. 10. Cardinale D, Colombo A, Bacchiani G, Tedeschi I, Meroni CA, Veglia F, Civelli
M, Lamantia G, Colombo N, Curigliano G, et al. Early detection of
anthracycline cardiotoxicity and improvement with heart failure therapy. Circulation. 2015;131(22):1981–8. Discussion In this study we have examined genetic variants previ-
ously associated with ACT in a cohort of severely af-
fected paediatric patients. Severe ACT was defined as a
fractional shortening < 24% as measured by echocardio-
gram, which was observed in 7% of the retrospective co-
hort [32]. These patients varied in clinical diagnosis, age,
total cumulative anthracycline dose and time to abnor-
mal echocardiogram, reflecting the patient population
treated at two major Australian paediatric hospitals. Our Table 3 Frequency of missense variants in patients with severe anthracycline-induced cardiotoxicity compared to global population
Gene
NOS3
ETFB
CBR3
ABCC2 1
ABCC2 2
RARG
GRP35
CYBA
SNP
rs1799983
rs79338777
rs1056892
rs17222723
rs8187710
rs2229774
rs12468485
rs4673
Total (of 15)
12
2
9
6
6
3
2
10
Percentage
80
13.33
60
40
40
20
13.33
66.67
Reported Frequencya
82
8
43
4
7
9
5
66
a 1000 genomes reported global frequency McOwan et al. Cardio-Oncology (2020) 6:5 McOwan et al. Cardio-Oncology (2020) 6:5 Page 5 of 6 Page 5 of 6 Page 5 of 6 date. Nevertheless, incorporating these genetic markers
into practice requires replication studies and further
functional validation [41]. Funding Study was supported by Children’s Cancer Foundation, My Room, The Royal
Children’s Hospital Foundation (RC, DAE). The Royal Children’s Hospital
Children’s Cancer Centre Tissue Bank is funded by Cancer In Kids @ RCH
(www.cika.org.au) and The Royal Children’s Hospital Foundation. Supported
by the Victorian Government’s Operational Infrastructure Support Program
and Australian Government National Health and Medical Research Council
Independent Research Institute Infrastructure Support Scheme (NHMRC
IRIISS). Importantly, both the onset of cardiotoxicity after
anthracycline treatment and the dose at which cardio-
toxicity was observed did not correlate with the burden
of variants within this cohort. While all variants exam-
ined where found within the cohort, with 14 out of 15
patients having at least one variant, no single variant was
observed in all patients. In agreement with our current
understanding, this suggests the genetic risk of ACT is
polygenic in nature and supports further genetic studies
with larger cohorts. Author details
1 1Murdoch Children’s Research Institute, The Royal Children’s Hospital,
Flemington Road, Parkville, Victoria 3052, Australia. 2Department of Pediatrics,
The Royal Children’s Hospital, University of Melbourne, Parkville, Victoria
3052, Australia. 3Department of Physiology, School of Biomedical Sciences,
The University of Melbourne, Parkville, Victoria 3010, Australia. 4Australian
Regenerative Medicine Institute, Monash University, Clayton, Victoria 3800,
Australia. Availability of data and materials
All data and materials are available upon request. All data and materials are available upon request. Ethics approval and consent to participate Ethics approval and consent to participate
Ethics approval was given by the institutional review board (HREC25102D)
and consent to participate was obtained in accordance with protocols laid
out in HREC25102D. Authors’ contributions Cardiac mortality among 200 000 five-year
survivors of Cancer diagnosed at 15 to 39 years of age: the teenage and
young adult Cancer survivor study. Circulation. 2016;134(20):1519–31. 33. Giantris A, Abdurrahman L, Hinkle A, Asselin B, Lipshultz SE. Anthracycline-
induced cardiotoxicity in children and young adults. Crit Rev Oncol
Hematol. 1998;27(1):53–68. 16. Hudson MM, Rai SN, Nunez C, Merchant TE, Marina NM, Zalamea N, Cox C,
Phipps S, Pompeu R, Rosenthal D. Noninvasive evaluation of late
anthracycline cardiac toxicity in childhood cancer survivors. J Clin Oncol. 2007;25(24):3635–43. 34. Felker GM, Thompson RE, Hare JM, Hruban RH, Clemetson DE, Howard DL,
Baughman KL, Kasper EK. Underlying causes and long-term survival in
patients with initially unexplained cardiomyopathy. N Engl J Med. 2000;
342(15):1077–84. 17. Sorensen K, Levitt G, Bull C, Chessells J, Sullivan I. Anthracycline dose in
childhood acute lymphoblastic leukemia: issues of early survival versus late
cardiotoxicity. J Clin Oncol. 1997;15(1):61–8. 35. Chen P, Yang W, Tian Y, Sun S, Chen G, Zhang C, Ma F, Xun Y, Shi L, Yang
C, et al. Electron transfer Flavoprotein subunit Beta is a candidate
endothelial cell autoantigen in Behcet's disease. PLoS One. 2015;10(4):
e0124760. 18. Nysom K, Holm K, Lipsitz SR, Mone SM, Colan SD, Orav EJ, Sallan SE, Olsen
JH, Hertz H, Jacobsen JR, et al. Relationship between cumulative
anthracycline dose and late cardiotoxicity in childhood acute lymphoblastic
leukemia. J Clin Oncol. 1998;16(2):545–50. 36. Garme Y, Saravani R, Galavi HR. Association of nitric oxide synthase 3 gene
polymorphism with the risk of type 2 diabetes. Biomedical reports. 2017;
7(1):85–9. 19. Sorensen K, Levitt GA, Bull C, Dorup I, Sullivan ID. Late anthracycline
cardiotoxicity after childhood cancer: a prospective longitudinal study. Cancer. 2003;97(8):1991–8. 37. Aminkeng F, Ross CJ, Rassekh SR, Hwang S, Rieder MJ, Bhavsar AP, Smith A,
Sanatani S, Gelmon KA, Bernstein D, et al. Recommendations for genetic
testing to reduce the incidence of anthracycline-induced cardiotoxicity. Br J
Clin Pharmacol. 2016;82(3):683–95. 20. Long-term Follow-Up Guidelines for Survivors of Childhood, Adolescent,
and Young Adult Cancers. Children's Oncology Group. 2018. http://www. survivorshipguidelines.org/. 38. Blanco JG, Sun C-L, Landier W, Chen L, Esparza-Duran D, Leisenring W, Mays
A, Friedman DL, Ginsberg JP, Hudson MM, et al. Anthracycline-related
cardiomyopathy after childhood cancer: role of polymorphisms in carbonyl
reductase genes--a report from the children's oncology group. J Clin
Oncol. 2012;30:1415–21. 21. Authors’ contributions TM, LC, AT, KK, collected and analysed data. MMC, ERP obtained funding and
analysed data. TM, wrote manuscript. AT, RC collected patient samples. DAE,
RC conception, funding, writing and editing. All authors read and approved
the final manuscript. 11. Ali MK, Ewer MS, Gibbs HR, Swafford J, Graff KL. Late doxorubicin-associated
cardiotoxicity in children. The possible role of intercurrent viral infection. Cancer. 1994;74(1):182–8. 11. Ali MK, Ewer MS, Gibbs HR, Swafford J, Graff KL. Late doxorubicin-associated
cardiotoxicity in children. The possible role of intercurrent viral infection. Cancer. 1994;74(1):182–8. Page 6 of 6 Page 6 of 6 McOwan et al. Cardio-Oncology (2020) 6:5 (2020) 6:5 McOwan et al. Cardio-Oncology McOwan et al. Cardio-Oncology (2020) 6:5 12. van Dalen EC, van der Pal HJ, Kok WE, Caron HN, Kremer LC. Clinical heart
failure in a cohort of children treated with anthracyclines: a long-term
follow-up study. Eur J Cancer (Oxford, England : 1990). 2006;42(18):3191–8. 30. Visscher H, Ross CJ, Rassekh SR, Sandor GS, Caron HN, van Dalen EC, Kremer
LC, van der Pal HJ, Rogers PC, Rieder MJ, et al. Validation of variants in
SLC28A3 and UGT1A6 as genetic markers predictive of anthracycline-
induced cardiotoxicity in children. Pediatr Blood Cancer. 2013;60(8):1375–81. 13. Mulrooney DA, Yeazel MW, Kawashima T, Mertens AC, Mitby P, Stovall M,
Donaldson SS, Green DM, Sklar CA, Robison LL, et al. Cardiac outcomes in a
cohort of adult survivors of childhood and adolescent cancer: retrospective
analysis of the childhood Cancer survivor study cohort. BMJ. 2009;339. nduced cardiotoxicity in children. Pediatr Blood Cancer. 2013;60(8):13 31. Hertz DL, Caram MV, Kidwell KM, Thibert JN, Gersch C, Seewald NJ, Smerage
J, Rubenfire M, Henry NL, Cooney KA, et al. Evidence for association of SNPs
in ABCB1 and CBR3, but not RAC2, NCF4, SLC28A3 or TOP2B, with chronic
cardiotoxicity in a cohort of breast cancer patients treated with
anthracyclines. Pharmacogenomics. 2016;17(3):231–40. 14. Kremer LCM, van der Pal HJH, Offringa M, van Dalen EC, Voûte PA. Frequency and risk factors of subclinical cardiotoxicity after anthracycline
therapy in children: a systematic review. Ann Oncol. 2002;13(6):819–29. 32. Conyers R, Costello B, La Gerche A, Tripaydonis A, Burns C, Ludlow L, Lange
P, Ekert P, Mechinaud F, Cheung M, et al. Chemotherapy-related
cardiotoxicity: are Australian practitioners missing the point? Intern Med J. 2017;47(10):1166–72. 15. Henson KE, Reulen RC, Winter DL, Bright CJ, Fidler MM, Frobisher C, Guha J,
Wong KF, Kelly J, Edgar AB, et al. Authors’ contributions Aminkeng F, Bhavsar AP, Visscher H, Rassekh SR, Li Y, Lee JW, Brunham LR,
Caron HN, van Dalen EC, Kremer LC, et al. A coding variant in RARG confers
susceptibility to anthracycline-induced cardiotoxicity in childhood cancer. Nat Genet. 2015;47(9):1079–84. 22. Semsei AF, Erdelyi DJ, Ungvari I, Csagoly E, Hegyi MZ, Kiszel PS, Lautner-
Csorba O, Szabolcs J, Masat P, Fekete G, et al. ABCC1 polymorphisms in
anthracycline-induced cardiotoxicity in childhood acute lymphoblastic
leukaemia. Cell Biol Int. 2012;36(1):79–86. 39. Rajic V, Aplenc R, Debeljak M, Prestor VV, Karas-Kuzelicki N, Mlinaric-Rascan I,
Jazbec J. Influence of the polymorphism in candidate genes on late cardiac
damage in patients treated due to acute leukemia in childhood. Leuk
Lymphoma. 2009;50(10):1693–8. 23. Wang X, Sun CL, Quinones-Lombrana A, Singh P, Landier W, Hageman L,
Mather M, Rotter JI, Taylor KD, Chen YD, et al. CELF4 variant and
Anthracycline-related cardiomyopathy: a Children's oncology group
genome-wide association study. J Clin Oncol. 2016;34(8):863–70. 40. Visscher H, Ross CJD, Rassekh SR, Barhdadi A, Dubé M-P, Al-Saloos H, Sandor
GS, Caron HN, van Dalen EC, Kremer LC, et al. Pharmacogenomic prediction
of anthracycline-induced cardiotoxicity in children. J Clin Oncol. 2012;30:
1422–8. 24. Ruiz-Pinto S, Pita G, Patino-Garcia A, Alonso J, Perez-Martinez A, Carton AJ,
Gutierrez-Larraya F, Alonso MR, Barnes DR, Dennis J, et al. Exome array
analysis identifies GPR35 as a novel susceptibility gene for anthracycline-
induced cardiotoxicity in childhood cancer. Pharmacogenet Genomics. 2017;27(12):445–53. 41. Tripaydonis A, Conyers R, Elliott DA. Pediatric Anthracycline-induced
Cardiotoxicity: mechanisms, pharmacogenomics, and pluripotent stem-cell
modeling. Clin Pharmacol Ther. 2019;105(3):614–24. Publisher’s Note 25. Ruiz-Pinto S, Pita G, Martin M, Alonso-Gordoa T, Barnes DR, Alonso MR, Herraez
B, Garcia-Miguel P, Alonso J, Perez-Martinez A, et al. Exome array analysis
identifies ETFB as a novel susceptibility gene for anthracycline-induced
cardiotoxicity in cancer patients. Breast Cancer Res Treat. 2018;167(1):249–56. Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations. Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations. 26. Blanco JG, Leisenring WM, Gonzalez-Covarrubias VM, Kawashima TI, Davies
SM, Relling MV, Robison LL, Sklar CA, Stovall M, Bhatia S. Genetic
polymorphisms in the carbonyl reductase 3 gene CBR3 and the NAD(P)H:
quinone oxidoreductase 1 gene NQO1 in patients who developed
anthracycline-related congestive heart failure after childhood cancer. Cancer. 2008;112(12):2789–95. 26. Blanco JG, Leisenring WM, Gonzalez-Covarrubias VM, Kawashima TI, Davies
SM, Relling MV, Robison LL, Sklar CA, Stovall M, Bhatia S. Genetic
polymorphisms in the carbonyl reductase 3 gene CBR3 and the NAD(P)H:
quinone oxidoreductase 1 gene NQO1 in patients who developed
anthracycline-related congestive heart failure after childhood cancer. Cancer. 2008;112(12):2789–95. 27. Wang X, Liu W, Sun CL, Armenian SH, Hakonarson H, Hageman L, Ding Y,
Landier W, Blanco JG, Chen L, et al. Hyaluronan synthase 3 variant and
anthracycline-related cardiomyopathy: a report from the children's oncology
group. J Clin Oncol. 2014;32(7):647–53. 27. Wang X, Liu W, Sun CL, Armenian SH, Hakonarson H, Hageman L, Ding Y,
Landier W, Blanco JG, Chen L, et al. Hyaluronan synthase 3 variant and
anthracycline-related cardiomyopathy: a report from the children's oncology
group. J Clin Oncol. 2014;32(7):647–53. 28. Wojnowski L, Kulle B, Schirmer M, Schluter G, Schmidt A, Rosenberger A,
Vonhof S, Bickeboller H, Toliat MR, Suk EK, et al. NAD(P)H oxidase and
multidrug resistance protein genetic polymorphisms are associated with
doxorubicin-induced cardiotoxicity. Circulation. 2005;112(24):3754–62. 29. Krajinovic M, Elbared J, Drouin S, Bertout L, Rezgui A, Ansari M, Raboisson
MJ, Lipshultz SE, Silverman LB, Sallan SE, et al. Polymorphisms of ABCC5 and
NOS3 genes influence doxorubicin cardiotoxicity in survivors of childhood
acute lymphoblastic leukemia. Pharmacogenomics J. 2016;16(6):530–5.
|
https://openalex.org/W4362481365
|
https://figshare.com/articles/journal_contribution/Figure_S3_from_Single_and_Dual_Targeting_of_Mutant_EGFR_with_an_Allosteric_Inhibitor/22532743/1/files/39995980.pdf
|
English
| null |
Figure S1 from Single and Dual Targeting of Mutant EGFR with an Allosteric Inhibitor
| null | 2,023
|
cc-by
| 491
|
Figure S3. The relative allelic fraction of T790M does not change the potency of JBJ-04-125-02 in H3255
cells but the presence of EGF blunts the efficacy of JBJ-04-125-02 in Ba/F3 and H1975 cells.
MTS cell viability assay examining the growth inhibitory effect of (A) dose escalated JBJ-04-125-02 and
osimertinib in H3255GR and H3255DR cells and (B) dose escalated JBJ-04-125-02 in the presence or absence
of 10ng/ml EGF in L858R/T790M Ba/F3 and H1975. Data is shown as relative mean compared to control
(DMSO; %) ± SD and is a representative graph of at least three independent experiments. (C) Western blotting
analyses of EGFR activity (phospho-EGFR, EGFR) and its downstream signaling (phospho-AKT, AKT, phospho-
ERK1/2, ERK1/2) in L858R/T790M Ba/F3 and H1975 cells treated with DMSO (as control) or increasing
concentrations of JBJ-04-125-02 or 1µM Osimertinib (as positive control). Tubulin was used as a loading control
for relative protein expression. Figure is a representative of at least three independent experiments. Figure S3. The relative allelic fraction of T790M does not change the potency of JBJ-04-125-02 in H3255
cells but the presence of EGF blunts the efficacy of JBJ-04-125-02 in Ba/F3 and H1975 cells. MTS cell viability assay examining the growth inhibitory effect of (A) dose escalated JBJ-04-125-02 and
osimertinib in H3255GR and H3255DR cells and (B) dose escalated JBJ-04-125-02 in the presence or absence
of 10ng/ml EGF in L858R/T790M Ba/F3 and H1975. Data is shown as relative mean compared to control
(DMSO; %) ± SD and is a representative graph of at least three independent experiments. (C) Western blotting
analyses of EGFR activity (phospho-EGFR, EGFR) and its downstream signaling (phospho-AKT, AKT, phospho-
ERK1/2, ERK1/2) in L858R/T790M Ba/F3 and H1975 cells treated with DMSO (as control) or increasing
concentrations of JBJ-04-125-02 or 1µM Osimertinib (as positive control). Tubulin was used as a loading control
for relative protein expression. Figure is a representative of at least three independent experiments. Figure S3. The relative allelic fraction of T790M does not change the potency of JBJ-04-125-02 in H3255
cells but the presence of EGF blunts the efficacy of JBJ-04-125-02 in Ba/F3 and H1975 cells. MTS cell viability assay examining the growth inhibitory effect of (A) dose escalated JBJ-04-125-02 and
osimertinib in H3255GR and H3255DR cells and (B) dose escalated JBJ-04-125-02 in the presence or absence
of 10ng/ml EGF in L858R/T790M Ba/F3 and H1975. Data is shown as relative mean compared to control
(DMSO; %) ± SD and is a representative graph of at least three independent experiments. (C) Western blotting
analyses of EGFR activity (phospho-EGFR, EGFR) and its downstream signaling (phospho-AKT, AKT, phospho-
ERK1/2, ERK1/2) in L858R/T790M Ba/F3 and H1975 cells treated with DMSO (as control) or increasing
concentrations of JBJ-04-125-02 or 1µM Osimertinib (as positive control). Tubulin was used as a loading control
for relative protein expression. Figure is a representative of at least three independent experiments. elative protein expression. Figure is a representative of at least three independent experiments. C. A. A. . C. B. C.
|
W2223643708.txt
|
https://www.mdpi.com/1424-8220/16/1/75/pdf?version=1452176184
|
en
|
Authentication Based on Non-Interactive Zero-Knowledge Proofs for the Internet of Things
|
Sensors
| 2,016
|
cc-by
| 10,367
|
Article
Authentication Based on Non-Interactive
Zero-Knowledge Proofs for the Internet of Things
Francisco Martín-Fernández *, Pino Caballero-Gil and Cándido Caballero-Gil
Received: 20 October 2015; Accepted: 4 January 2016 ; Published: 7 January 2016
Academic Editor: Rongxing Lu
Departament of Computer Engineering, University of La Laguna, 38271 La Laguna, Tenerife, Spain;
pcaballe@ull.edu.es (P.C.-G.); ccabgil@ull.edu.es (C.C.-G.)
* Correspondence: fmartinf@ull.edu.es; Tel.: +34-9223-181-76
Abstract: This paper describes the design and analysis of a new scheme for the authenticated
exchange of confidential information in insecure environments within the Internet of Things, which
allows a receiver of a message to authenticate the sender and compute a secret key shared with it.
The proposal is based on the concept of a non-interactive zero-knowledge proof, so that in a single
communication, relevant data may be inferred to verify the legitimacy of the sender. Besides, the new
scheme uses the idea under the Diffie–Hellman protocol for the establishment of a shared secret key.
The proposal has been fully developed for platforms built on the Android Open Source Project, so it
can be used in any device or sensor with this operating system. This work provides a performance
study of the implementation and a comparison between its promising results and others obtained
with similar schemes.
Keywords: non-interactive zero-knowledge proof; authentication; mobile ad hoc network
1. Introduction
The Internet of Things (IoT) is a trending concept that arises from the need to monitor
and interconnect billions of information devices, typically equipped with sensors, actuators,
microprocessors, communication interfaces and/or power sources. New challenges related to
wireless security appear in IoT because the most common medium used for communication among
hyper-connected devices is wireless. Thus, since most IoT objects have limited processing power,
finite memory and low battery life, new lightweight cryptographic algorithms, in terms of processing
and memory requirements, are necessary to obtain the efficiency of end-to-end communication and
applicability to low-resource devices [1].
With the advent of increasingly powerful technology that is reduced in size and weight, the
security level of the cryptographic schemes that are used in wireless communications has been
increasing due to the rise of new algorithms based on harder mathematical problems, such as
elliptic curves. In particular, the evolution of networks towards IoT has implied that this process is
now accelerated.
Due to the emergence of this new paradigm of interconnected objects, where the physical
dimension mimics the logical dimension, it is necessary to encode more than 100,000 million objects [2],
because each person is surrounded by approximately 3000 objects. As previously mentioned, a key
aspect to consider is the way of communication between these objects. Thus, the mobile nature and
small size of many of these devices that form the IoT usually imply that such a communication is
wireless and that the resulting network is established as a mobile ad hoc network (MANET), which is a
network composed of mobile devices, wirelessly connected, and generally characterized by properties
of auto-configuration.
Sensors 2016, 16, 75; doi:10.3390/s16010075
www.mdpi.com/journal/sensors
Sensors 2016, 16, 75
2 of 20
Each device that is a member of a MANET can move freely, which involves that the link conditions
between different devices can be continuously changing and requires that any node can act as a router
for the communications of other nodes. Another important aspect of these networks is that, in general,
they can operate independently or be connected to the Internet. When a member of the network is
connected to the Internet, usually the network enables Internet access to the other devices that do not
have a direct Internet connection.
Regarding security, in MANETs, many types of threats exist that can affect their use. Two of the
most dangerous attacks are against the security of wireless communications through denial-of-service
and man in the middle (MitM) attacks.
The proposal described in this work aims to be applied mainly to IoT devices used in mobile
environments, such as vehicles, for example. In particular, this work proposes the design and
implementation of a new lightweight cryptographic scheme to enable secure wireless communications
in a MANET. It describes the design and analysis of a new scheme based on a non-interactive
zero-knowledge proof for the authenticated exchange of confidential information in IoT, which allows a
receiver node to authenticate the sender and to compute a shared secret key from the received message.
This paper is organized as follows. Section 2 introduces a few related works. Some necessary
preliminaries are defined in Section 3. Then, a non-interactive zero-knowledge proof authentication
scheme is proposed in Section 4. Several applications of the proposed scheme in sensors and
IoT are briefly described in Section 5. Security aspects of the proposal are analyzed in Section 6.
The performance evaluation is presented in Section 7, followed by a comparative analysis given in
Section 8. Finally, Section 9 closes the paper with a few conclusions.
2. Related Works
Security in the Internet of Things is a primary factor. As a proof of that, the new operating system
that Google has introduced for the Internet of Things, called Brillo, follows the “secure by default”
paradigm. The work presented in [3] explains perfectly the major security threats to the Internet of
Things, classified into three main categories:
•
•
•
Related to the physical nature of smart objects: cloning of smart things by untrusted manufacturers,
malicious substitution of smart things during installation, firmware replacement attack and
extraction of security parameters since smart things may be physically unprotected.
Related to intercommunication between smart objects: Eavesdropping attack if the communication
channel is not adequately protected, man-in-the-middle attack during key exchange, routing
attacks and denial-of-service attacks.
Related to sensible data processed by the smart objects: Privacy threats.
If secure communication is established over insecure channels through symmetric cryptography,
the secure pre-distribution of secret keys is one of the most essential tasks. This topic has attracted
much attention among researchers [4,5] throughout the years. However, the best-known system
for the secure distribution of secret keys via insecure channels continues being the Diffie–Hellman
scheme [6], which allows two users to compute a shared secret key from two secret numbers and
a public exchange of information, thanks to the discrete logarithm problem. Such an algorithm
does not include user authentication, which leads to the possibility that am MitM attack can be
launched. In order to avoid it, asymmetric cryptography and public key certification can be used.
The present work faces the problem of the secure distribution of secret keys based on the idea under
Diffie–Hellman scheme, but including authentication and using graph theory problems instead of the
discrete logarithm problem.
In the case of MANETs, different proposals exist to protect communications, which are based
either on secret-key cryptography or on public-key cryptography, like, for example, [7] and [8].
On the one hand, the security level of many symmetric schemes is high, but their major drawback
is the difficulty of the pre-distribution of shared secret keys. In an environment like that of MANETs
Sensors 2016, 16, 75
3 of 20
in the IoT [9], the assumption regarding the existence of a fully-secure channel to transmit the
symmetric keys is very difficult to achieve. In addition, if the MANET is large and based only
on symmetric cryptography, the number of secret keys that would be required is very high. Thus, as
previously ]mentioned, to solve the problem of secure secret key distribution, asymmetric cryptography
can be used.
On the other hand, public-key cryptography offers the capability of a digital signature
scheme [10] if the sender decrypts with its private key and the receiver encrypts with the public
key of the sender. Through a digital signature, authentication of both the sender and message, e.g.,
identification and integrity, can be guaranteed. Interestingly, the ability to use digital signatures that
public-key cryptography provides is exactly what solves the main challenge it presents, which is
the need to establish trust in public keys to prevent MitM attacks. In an MitM attack, the attacker
makes independent connections with two nodes and relays messages between them, making them
believe that they are talking directly to each other over a private connection, when in fact the entire
conversation is being controlled by the attacker. The solution to this problem involves that each public
key is certified so that the digital signature contained in the certificate guarantees the identification of
the user responsible for the public key.
Several models to achieve certification of public keys exist [11]. The most common one is based
on a public key infrastructure (PKI), where trust is placed in certificate authorities. Another interesting
scheme is based on a decentralized trust model called the web of trust, where each user has a ring with
a group of public keys that it trusts. The authors of [12] propose an efficient public key management
scheme that is suitable for fully-self-organized MANETs, where all nodes play identical roles. Finally, a
certificate-less alternative for PKIs is identity-based cryptography, where the public key of each
user is some unique piece of information related to its public identity, so that public-key certificates
are unnecessary.
The main disadvantage of asymmetric cryptography is the high computational complexity of the
schemes, since most public-key cryptosystems are too heavy to be used in lightweight environments
like MANETs in IoT. To solve this issue, this paper proposes a combination of symmetric and
asymmetric cryptography to allow the use of secret session keys in these environments. In particular,
the proposal offers both strong authentication of legitimate nodes through open communications and
the exchange of secret keys shared between pairs, which can be used as session keys.
Node authentication is here performed using an approach based on the idea of zero-knowledge
proof (ZKP) [13], which defines a method to prove the knowledge of a certain piece of information
without revealing anything about it. Typical ZKPs are based on several challenges and responses,
involving a successive exchange of messages, which implies the need to have a stable and continuous
connection between nodes [14]. However, this assumption is impossible in a volatile environment like
IoT, where sometimes, devices move at a high speed, such as, for example, smart vehicles. In these
cases, a massive exchange of messages to run a typical ZKP can be infeasible due to possible connection
failures during the protocol. In order to deal with this problem, the idea of non-interactive ZKP (NIZKP)
has emerged in the literature [15,16].
In an NIZKP, all of the challenges of a typical ZKP are condensed into a single package sent in
a single message. This leads to the optimization of the time necessary for the exchange of messages,
so that just a single message is necessary, and even this message can be sent as a beacon in broadcast
mode. The work [17] shows a method that transforms an interactive protocol into a non-interactive
protocol, which can be applied to turn interactive ZKPs into NIZKPs thanks to the use of hash function.
Besides, on the one hand, as a general theoretical result, the authors of [18] present the first NIZKP for
NP whose construction is based on one-way permutations and certified trapdoor permutations [19].
On the other hand, as a specific practical result, the work [20] shows an NIZKP of the Hamiltonian
cycle problem, which can be used with the proposal described here.
Sensors 2016, 16, 75
4 of 20
3. Preliminaries
If a prover P is trying to prove to a verifier V its knowledge of a solution to a difficult problem,
it can use a zero-knowledge proof so that V is not able to trick P and discover the solution or any
information that can help it to compute anything faster than before. Thus, what V can see thanks to
the protocol should be something that it could have computed by itself. A ZKP must fulfil three main
properties, usually called completeness, soundness and zero-knowledge. Completeness means that
for any valid input, a prover P can always complete the proof successfully; soundness means that no
malicious prover P can construct a valid proof system; and zero-knowledge means that no malicious
verifier V is able to derive extra knowledge from the interaction.
This work is based on a non-interactive zero-knowledge proof, which can be formalized as follows.
If {0, 1}∗ denotes the set of all strings and R denotes a witness, for a language L ⊆ {0, 1}∗ , a pair of
probabilistic Turing machines ( P, V ), in which P has probabilistic polynomial time power and V has
deterministic polynomial time power, is said to be a non-interactive zero-knowledge proof system of
the language L if it fulfills the following conditions related to correctness and security against malicious
provers and verifiers:
•
Completeness: For any polynomial p(·) and common input x ∈ L, x is accepted by V with a
probability greater than 1 − e:
Pr [V ( x, R, P( x, R)) = 1] ≥ 1 −
•
(1)
Soundness: For any interactive Turing machine P0 representing a dishonest prover, any polynomial
p(·) and any common input x ∈ L provided by P0 x is accepted by V with a probability at most e:
Pr [V ( x, R, P0 ( x, R)) = 1] <
•
1
p(| x |)
1
P(| x |)
(2)
Zero-knowledge: For any x ∈ L provided by P, no information is revealed from x to V that it
could not compute alone before running the protocol, which means that there is a probabilistic
polynomial time algorithm M, such that:
V ( x ) = x, ( R ∈ 0, 1c(| x|) , P( x, R)) ≈c M( x ) x∈ L
(3)
One of the most important factors of any ZKP is the choice of the mathematical problem that forms
its basis. The work [21] showed that, under certain complexity assumptions, on the one hand, any NP
problem can be used to define a ZKP, and on the other hand, only problems in BPP (bounded-error
probabilistic polynomial time) can be used to describe non-interactive zero-knowledge proofs.
In this work, the chosen problem is the graph isomorphism problem. An isomorphism between
two graphs is a bijection that preserves the adjacency relationship, i.e., any two vertices of a graph
are adjacent if and only if so are their images in the other graph. The graph isomorphism problem
consists of determining whether two graphs are isomorphic or not. This problem has been used in
cryptography [22] because an efficient algorithm to solve it in general is yet unknown. In particular,
the determination of whether two graphs with the same number v of vertices and the same number of
edges are isomorphic or not involves a brute force attack, because it requires checking whether some
of the v! possible bijections preserve adjacency. In general, the graph isomorphism problem is one of a
few problems in computational complexity theory belonging to NP, but not known to belong to a P
or to an NP-complete subset [23]. Therefore, its resolution, depending on the size and the type of the
involved graphs, can be very difficult. In particular, the graph isomorphism problem has been proven
to be in BPP, which opens the door to the definition of NIZKPs based on it.
4. NIZKP-Based Authentication
The proposal here described is based on a variant of NIZKP that uses only a single message to
verify the knowledge and can be adapted to different levels of security, so that the larger the number
Sensors 2016, 16, 75
5 of 20
of challenges, the higher the level of safety for the verifier. In particular, the parameters used in the
proposal are shown in Table 1.
Table 1. Proposal parameters.
Notation
G
SolG
n
Chai
Gi
Isoi
Resi
h(·)
LSB(·)
Eki (·)
Subkey
Meaning
Graph known by all legitimate nodes, on which they know how to solve a hard problem
Solution to the hard problem in G
Number of challenges
i-th challenge proposed by the verifier
i-th isomorphic graph used as a commitment
Isomorphism between G and Gi
i-th response corresponding to the challenge Chai on the graph Gi
Cryptographic hash function
Least significant bit of an input string
Symmetric encryption with key k i
Contribution of a node to the session key
In [15], it was shown that the validity of NIZKPs relies on the computational assumption of an
ideal cryptographic hash function. Thus, the proposed scheme uses a cryptographic hash function that
fulfills such a requirement.
In the described scheme, each node broadcasts a message to identify itself as a legitimate network
node. The message consists of a number of commitments defined by isomorphic graphs generated
from an initial graph known by all legitimate nodes. For instance, that graph may represent the
network, so that each node represents a network user.
Each commitment of the message, except the first one, is encrypted and can only be decrypted
after verifying all of the previous ones.
In particular, the message is divided into n + 1 segments that are all encrypted with different
keys, except the first segment, which is not encrypted (see Figure 1). Thus, a legitimate network user
can authenticate itself to join a communication session with another node if this latter node is able
to decrypt all of the segments of the message broadcast by the first one, so that it can reach the last
segment, which contains the contribution of the sender node to the session key.
Figure 1. Components of sent messages.
The encryption key of each segment depends on the previous segment, so that although someone
wants to decipher only the last segment, this is impossible, because it would require the decryption
of all previous segments. The security level of the scheme depends on the number of segments of
the message, which represent different challenges. The greater the number of segments, the more
Sensors 2016, 16, 75
6 of 20
complex it is to reach the last segment and to obtain the information required for the establishment of
the shared key.
After the two-way authentication using the same procedure, based on the idea of
the Diffie–Hellman scheme, both nodes will know the shared session key, but with both
exchanged subkeys.
Each segment, except the last one, contains an isomorphic copy of the original graph. A one-way
hash function known by all legitimate network nodes is used to define the challenge that the receiver
must solve on each isomorphic graph. Moreover, the same hash function is used to define the
encryption key for each message segment.
The operations that the receiver must perform on the message are:
1.
2.
Process the first segment of the message, which is not encrypted.
Compute, using the hash function, the challenge that matches the information included in
the segment.
3. Check whether the response corresponds to the challenge and the isomorphic graph.
4. From the challenge, compute the key it has to use to decrypt the next segment.
5. Apply Steps 2 through 4 until the last segment, which once deciphered contains the information
needed to establish the shared secret key.
If the used hash function, problem and graph are adequate, the probability that Chai = 0 is 1/2.
Thus, the probability that a legitimate node knows the key k1 is 1/2, that it knows the two keys k1 and
k2 is 1/22 ,..., and that it knows the n keys k1 , k2 , ..., k n is 1/2n .
The challenges have been chosen as the known ZKP is based on isomorphic graphs. However, in
the NIZKP here proposed, the challenges are defined from the result of a Boolean output of a hash
function defined through the least significant bit (LSB) applied on each committed isomorphic graph.
Thus, for each challenge, the response is defined as follows:
•
•
If Challenge = 0, the response is the isomorphism.
If Challenge = 1, the response is the solution to the problem in the isomorphic graph.
The flowchart of the algorithm to be run by the receiver is shown in Figure 2. The pseudocode of
the proposed scheme (Algorithm 1) is shown below.
Figure 2. Flowchart of the proposed algorithm.
Sensors 2016, 16, 75
7 of 20
Algorithm 1 Processing
//Params: beacon, encrypted message segments
//Params: t_seg, dimension of beacon segments
//Params: solg, solution in the original graph
//Return: subkey, contribution to the key
function getData (char[] beacon, int tseg, char[] solg)
01: var segs[]; // Stores the message segments
02: // Message is divided into tseg − size segments
03: segs = beacon.splitByTam(tseg);
04: // Isomorphic graph and response
05: // First segment is not encrypted
06: var gi = getGi(segs[0]);
07: var res = getRes(segs[0]);
08: // The challenge is computed
09: var cha = LSB.hash(gi.getBytes());
10: // Check whether the response is correct
11: if (res != response(gi, cha))
12: return; // If not correct, abort
13: endif
14: // The solution is obtained in gi
15: var sol = solve(gi);
16: // ki is the encryption key of the next segment
17: var ki = cha ∗ hash(sol ) ⊕ cha ∗ hash(sol ⊕ solg)
18: var decryption;
19: // The following steps are repeated
20: for (int i = 1; i < segs.size() − 1; i + +){
21: // The segment is decrypted with the key ki
22: decryption = Crypto.decrypt(segs[i], ki);
23: gi = getGi(decryption);
24: res = getRes(decryption);
25: cha = LSB.hash(gi.getBytes());
26: if (res != response(gi, cha))
27:
return;
28: endif
29: sol = solve(gi);
30: ki = cha ∗ hash(sol ) ⊕ cha ∗ hash(sol ⊕ solg)
31: }
32: // Decryption of the last segment provides the
33: // contribution to the shared key.
34: return Crypto.decrypt(segs[segs.size()], ki);
endfunction
The receiver can access the last message segment thanks to the decryption key obtained from
the previous segment after running the algorithm. This last segment contains the contribution of the
sending node to the potential session key shared with each receiver.
The initial graph and a secret key that is a solution to a difficult problem in such a graph are
known by all legitimate network users. For example, this solution may be a Hamiltonian cycle because
the Hamiltonian cycle problem for arbitrary graphs is considered a difficult problem. The Hamiltonian
cycle problem consists of determining whether there is a path in the graph that visits each vertex
exactly once. This problem is often considered NP-complete, but there are some particular graphs
Sensors 2016, 16, 75
8 of 20
for which the problem is polynomial or even linear. Because of this, in this paper, if the Hamiltonian
cycle problem is used, the use of non-planar graphs is suggested. A graph is planar if it can be drawn
in a plane without graph edges crossing. In order to check in linear time whether a given graph is
non-planar, Theorem 1 can be used:
Theorem 1. For any simple, connected, planar graph with v vertices and e edges: If v ≥ 3 then
e ≤ 3v − 6.
Thus, this theorem can be used to prove that a graph is not planar when the above relationship
between v and e is not fulfilled. In fact, when generating the graph, if a planar graph is obtained, edges
are added at random until the theorem’s condition is not satisfied, thereby ensuring that the graph
is non-planar.
The hash function chosen for computing the challenges and encryption keys for each message
segment in the implementation of the proposed scheme is the new standard hash function
SHA-3 [24,25].
The symmetric system to encrypt the message segments used in the implementation is the stream
cipher of the fourth generation of mobile communications (LTE) [26,27], known as SNOW3G [28]. This
choice is based on the linear computational complexity both in encryption and decryption, which
guarantees the efficiency and speed of the encryption and decryption processes.
5. Applications to the Internet of Things
All of the applications that have been implemented and analyzed in this section to prove the
effectiveness of the scheme proposed in this work are for a decentralized environment where Wi-Fi
Direct and/or Bluetooth Low Energy are used for wireless communications, because already, many of
the interconnected objects have access to these technologies, and they are available for Android. In the
future, similar applications will be possibly developed based on the prospective LTE Direct technology.
In particular, the cases in which the required degree of confidentiality is that of communications
encrypted with a secret session key are the main use cases of the described system.
The distribution and management of credentials for secure communication can be a relatively
simple task if only a restricted group of centralized application providers is considered. Instead, in
a distributed architecture, like the one of the Internet of Things, many more problems emerge, as
explained in [29], because any device can be connected to any device at any time, and devices might
not have had any previous contact with each other in advance. Hence, in this scenario, the problem of
key management becomes an important problem. A solution may be based on using a scheme like the
proposed one in this paper because it is quite flexible and adaptable to the needs of the devices that
interact in IoT.
5.1. Applications in Mobile Ad Hoc Networks
Conducting business transactions in MANETs is an interesting use case of the proposal, because
in that scenario, a legitimate network node might want to share its own resources with other legitimate
nodes to carry out such transactions. Due to their mobile nature, often, the nodes of a MANET do not
have Internet access in many places. Thus, those legitimate nodes that have an Internet connection
may want to rent their connection to other legitimate nodes. For this task, both nodes can establish
a shared secret session key, which can be done with the scheme proposed in this paper.
In general, two different scenarios for the use of variants of the proposed scheme are described
below: To report authenticated information unidirectionally either without using secret keys or using
a public key. On the one hand, a node may only want to transmit information from an authenticated
way (see Figure 3) so that other legitimate nodes hearing the messages rely on the information that
the sending node transmits, thanks to its knowledge of the secret network key used to generate the
isomorphic graphs and solutions involved in the described protocol. Two specific examples of use
cases within a MANET in this new scenario are event notification or dissemination of advertising shops.
The transmission of advertising using the scheme proposed in this paper implies that only legitimate
Sensors 2016, 16, 75
9 of 20
nodes can send advertising, which avoids massive spam from nodes that do not belong to the network.
On the other hand, a legitimate node may want to spread its public key in an authenticated way and
only to other nodes that also belong to the network (see Figure 3). This use case requires the application
of another variant of the proposed scheme where sent beacons hide in their last segment the public key
of the sender node. This implies that only legitimate network users can access the public key of the
sender hidden in the last segment of the beacon, because the challenges and responses are based on a
secret network key. This approach can be used whenever the spread of an event through a MANET
requires the use of a digital signature scheme by legitimate nodes, which send their public keys to
other legitimate nodes of the network in an authenticated way.
Figure 3. Types of MANET nodes.
5.2. Applications in Vehicular Ad Hoc Networks
A vehicular ad hoc network (VANET) can be seen as a special type of MANET where the nodes
are vehicles and the main objective is to prevent adverse circumstances on the roads and achieve more
efficient traffic management.
One of the most important aims in the design of such networks is to resist security attacks [30].
Thus, in the area of VANETs, the proposed scheme can be used to authenticate vehicles in isolated
areas (mountain areas, tunnels, etc.), where no Internet connection is available. Each vehicle can
send an authentication message and agree on a shared key to communicate thereafter, following the
proposed scheme based on the Diffie–Hellman idea.
Furthermore, the proposal can be applied to solutions of other problems in VANETs. For example,
it can be used to authenticate the information sent from the smart traffic lights to vehicles. Some critical
environments require that this information is sent authenticated, so that only legitimate users of the
network can decrypt and process it. Thus, for instance, there are proposals like [31] that describes
a low-cost solution based on a smart traffic light using a light sensor that provides information in
real time about the traffic light color. The solution uses a Bluetooth Low Energy (BLE) module that
allows transmitting the state of the traffic light to nearby vehicles, as a beacon notification. This beacon
notification can be sent authenticated through the proposal explained in this paper.
5.3. Applications in Sensors Networks
Regarding sensor networks, the proposal presented here can be interesting, specifically for its
application in wireless sensor networks (WSNs). WSNs have evolved significantly in the last few years,
generating a promising research area about a fruitful and useful technology. This technology involves
Sensors 2016, 16, 75
10 of 20
two types of entities: Sensor nodes and base stations. In general, base stations are more powerful than
sensor nodes, but this trend is changing thanks to advances in low-powered technology.
Nowadays, it is possible to create a WSN using platforms like Arduino, Rasperry Pi, Odroid,
Intel Edison, etc., which can have several sensors. Since some applications in WSNs only require the
information of a specific sensor, the scheme proposed in this paper can be used for these platforms to
send the sensor information independently and in an authenticated way by using a broadcast beacon
to send the data of each sensor. Thus, sent data will only be accessible to legitimate entities.
The applicability of the proposed solution is more to sensor platforms, such as those coordinated
through Arduino, than to individual sensors, because Android can be installed in them. Thus, the
secure communications based on the proposed scheme can be used on any sensor platform based on
Arduino, such as Odroid.
Besides, the proposed authentication scheme can be used to complete other solutions and to add
a layer of security. For example, existing WSN models based on preloaded parameters, like broadcast
keys for sensor nodes, can be improved by using the scheme presented in this paper to generate shared
keys and using them as broadcast keys for the sensor nodes.
6. Security Proofs
In the following, several known attacks are analyzed in relation to the proposal.
6.1. Attacks on the Cryptographic Operations
On the one hand, the security of the scheme depends on the chosen hash function.
A collision attack on a cryptographic hash tries to find two inputs producing the same hash value.
Another possible weakness can be a preimage attack, which tries to find a message that has a specific
hash value. A cryptographic hash function should resist both preimage and collision attacks.
In this work, the implementation uses the hash function SHA-3 for several operations. The algorithm
behind SHA-3 is the Keccak function. With Keccak, it is possible to target a given security strength level
by choosing the appropriate capacity, i.e., for a given capacity c, Keccak is claimed to resist any attack
c
up to complexity 2 2 . This approach is similar to the one suggested to choose the security strength used
in [32] by NIST (National Institute of Standards and Technology).
On the other hand, the security of the proposal depends on the symmetric cipher used to
encrypt each segment. The encryption used in the implementation is the basis of the security in
LTE communications, called SNOW 3G. The SNOW 3G core is supplied as portable Verilog, with a
Verilog Hardware Description Language (VHDL) version available, thus allowing customers to carry
out an internal code review to ensure its security.
Therefore, the security of cryptographic operations is guaranteed due to the used standards:
SHA-3 and SNOW 3G. The SHA-3 algorithm is based on a permutation where collisions and preimages
can be found for its cryptographic hash function in one query to the permutation. The sponge
construction has been proven to be indifferentiable from a random oracle if the underlying permutation
is assumed to be ideal [33], and this result applies to Keccak function. Optimal bounds have been
obtained on collision resistance and on preimage and second preimage resistance for Keccak in the
ideal permutation model [34]. Regarding SNOW 3G, it has linear time complexity, which guarantees
efficiency during the encryption/decryption process. Furthermore, security proofs of SNOW 3G
are based on the assumption that this encryption system behaves like a perfect random function of
the key [35].
6.2. Attacks on the Graph Problem
The specific problem under the ZKP is fundamental for the security of the scheme.
The implemented scheme uses the two graph problems of the graph isomorphism and of the
Hamiltonian cycle.
Sensors 2016, 16, 75
11 of 20
Regarding possible attacks to the problem of the graph isomorphism, some efficient algorithms for
some specific graphs have been proposed. For example, in [36], several probabilistic algorithms were
discussed; and in [37], some algorithms for determining whether two graphs are isomorphic or not
have been described. However, the proposed scheme can use graphs of different sizes, and depending
on the size of these graphs, the security can be increased. The generated graphs are completely random,
and therefore, none of the proposed algorithms are useful for finding the secret. Therefore, under the
hypothesis of using well-chosen instances of the problem, the graph isomorphism problem can be
considered NP-complete for the particular execution of the proposal.
With respect to the Hamiltonian cycle problem, under the condition of the defined scheme, the
problem can be also considered NP-complete. This is achieved with the use of non-planar graphs,
because through the theorem shown in a previous section, we can ensure that in the implementation,
none of the graphs that are generated in the scheme are planar. Again, under the hypothesis of using
well-chosen instances of the problem, the Hamiltonian cycle problem can be considered NP-complete
for the particular execution of the proposal. Thus, a real attack based on the used graph problems is
not possible because the complexity of the chosen problems can be considered NP-complete.
6.3. Man in the Middle Attack
An MitM attack happens when an attacker secretly relays and possibly alters the communication
between two parties who believe they are directly communicating with each other. This is one of the
most used attack schemes in wireless networks.
In the case of the proposal, an MitM attack cannot be carried out because there is no way to
gain information during the transaction. In particular, the scheme uses a single beacon to send some
information from the sender to the receiver. Therefore, there is no communication between them, so
that other users cannot intercept communication and, hence, cannot impersonate communications.
If the scheme is used to establish a secret key through the Diffie–Hellman algorithm, thanks
to the fact that the protocol uses strong mutual authentication with secret keys, it is robust against
an MitM attack. Mutual authentication refers to two parties authenticating each other at the same
time. Consequently, an MitM attack against the proposed scheme would not succeed. The attacker
could intercept beacons, but without access to secret parameters of the scheme, it cannot get any
confidential information. The configuration parameters of the proposed scheme are only accessible for
the legitimate users of the network and are provided by a trusted third party during the initialization
of the scheme.
6.4. Other Attacks
In MANETs, due to the lack of a centralized structure, denial of service (DoS) attacks can be
frequent. In order to protect the proposed scheme from DoS attacks, although the communication
produced with the application is through a non-secure channel, only legitimate nodes of the networks
are able to send and decrypt valid messages.
The proposed scheme is resistant against a brute force attack. A brute force attack, also called
exhaustive key search, is a trial-and-error method used to obtain relevant data through the generation
of a large number of consecutive guesses about the desired data. In the proposal described in this
paper, since the desired data are contained in the last segment of the sent package, a brute force attack
on the key used to encrypt the last segment would be required. In order to make it possible that a brute
force attack could be used to discover the key used to encrypt such a segment, it could be necessary to
check all of the possible keys. The key used to encrypt each segment has a fixed size defined by the
hash function used to obfuscate the response to the previous segment challenge. SHA-3 has been used
as a hash function in the implementation, so since its smallest output is 224 bits, a brute force attack
would involve checking 2224 combinations. If the scheme is used as a key agreement protocol, since in
that case, interaction between parties exists, a maximum response time could be defined in order to
prevent possible brute-force attacks.
Sensors 2016, 16, 75
12 of 20
Another dangerous attack in MANETs is the sibling attack, which occurs when a node
illegitimately uses multiple identities. This problem is avoided in the proposed scheme thanks
to the distributed nature of the used NIZKP.
Finally, the proposal is also resistant to identity theft because node access is controlled by
an NIZKP.
In a nutshell, usual attacks have no harmful effect on the proposal, because its security is supported
by NIZKP based on complex mathematical problems and current standard hashing and encryption.
7. Implementation
The described scheme is intended for its use in areas related to the Internet of Things. It has been
implemented for Android and Android Wear platforms, which are two examples of the proliferation
of devices in this new dimension of the Internet. Android is the most popular smartphone operating
system, with over 80% market share worldwide. Android Wear is the operating system based on
Android for wearable devices of the same company and has more than 90% of the market share in the
devices of its kind. Therefore, all of the results presented here are the result of the implementation of
the scheme in these two platforms belonging to the Android Open Source Project. The source code is
open source under a Git repository on the GitHub Platform [38].
Figure 4 shows a screenshot of the Android application that was created to analyze the
performance of the scheme in smartphones.
Figure 4. Android application screenshot.
Despite the implementation described in this section having been focused on IoT devices where
it is possible to have an Android operating system, like current smartphones and smartwatches,
this does not mean that the necessary devices have to be extremely powerful devices. For instance,
there are sensor platforms, like Odroid, that, despite their small size, are able to run an operating
system like Android, so consequently, they can be used to run the proposed system. Besides, Google
has recently introduced a new operating system for IoT, called Brillo, which is a fork of Android,
Sensors 2016, 16, 75
13 of 20
so the implementation described in this paper is easily adaptable to future devices with the Brillo
operating system.
7.1. Package Format
One of the premises that the scheme meets is that it is lightweight in terms of size and the speed of
computation, so it fulfills the requirements of the devices of the IoT. Therefore, the size of the message
or package has been reduced in the implementation to be as small as possible in order to use the
smallest possible space in memory and in order to have fast communication between devices. Because
of this, also the storage format of each of the elements that make up the message has been optimized.
Thus, the following measures have been taken to serialize these elements:
•
Graphs: Graphs are serialized by denoting their adjacency matrices into integers, because this
is their fastest implementation. This serialization has been also improved by using hexadecimal
rather than integer numbers. In this case, the storage size is smaller, but the speed serialization is
quite slow. Thus, a faster serialization has been chosen compared to a slight improvement in the
package size, so graphs have been serialized through their adjacency matrices.
For instance, given the adjacency matrix:
0
1
1
0
1
1
0
1
0
0
1
1
0
0
1
0
0
0
0
1
1
0
1
1
0
it can be represented in one dimension as:
0110110100110010000110110
This one-dimensional representation is serialized by converting it into an integer of eight digits,
formed of five integers separated by the character “,”
13, 20, 25, 1, 22
•
Solutions: Solutions have been serialized by using lists of integers separated by the character “,”
because both types of solutions, the Hamiltonian cycle and the isomorphism between graphs, can
be represented as lists. For example, if the isomorphism between two graphs is 1 → 2, 2 → 5,
3 → 1, 4 → 3, 5 → 4, using array indexes as original nodes and the values of the array as the
values of the new nodes, the isomorphism is represented as:
2, 5, 1, 3, 4
•
Segments: Each segment of the message is serialized in hexadecimal. Besides, all of the segments,
but the first one, are encrypted as explained in previous sections. The last segment contains
a secret encrypted by the key that can be obtained with the solution to the challenge of the previous
segment. For instance, the aspect of a segment containing an isomorphic graph and challenge and
response corresponding to the graph is the following, expressed with hexadecimal characters:
A324D0E3F19
•
Message or package: The complete message is the concatenation of all of the generated segments.
To separate the segments, the character “|” is used. An example of a package with three
segments is:
A324D0E3F19| F9223B3EE34| DC34F212ACB
Sensors 2016, 16, 75
14 of 20
7.2. Package Size
Given the format that has been used to represent the elements that are part of the proposed
scheme, optimal package sizes have been achieved.
The message size is given by the dimension of the graph used to represent the network.
The more nodes a graph has, the more space is needed. This involves the segments being larger,
resulting in larger package sizes.
Therefore, we have analyzed which sizes per segment are recommended depending on the
number of nodes in the graph, which are shown in Figure 5.
Figure 5. Segment size trend.
This clearly reveals a polynomial tendency of order two that represents the relationship between
the size of the segments and the number of nodes of the graph that represents the network. Thus, the
following polynomial function (see Equation (4)) has been calculated that defines the data, so that
segment sizes for graphs with more nodes can be estimated.
y = 0.9765x2 + 5.8046x − 1.1513
(4)
Thus, for instance, a scheme in which the graph of the network is defined by 50 nodes and
the number of challenges that defines the scheme package is six would require a package size of 16
kilobytes without including the size of the shared secret. Thus, in order to send a message in a single
package securely by using this scheme, we have used six challenges for 50 nodes, and the sent message
has an overhead of only 16 kilobytes.
7.3. Package Generation Time
The computational time required for the devices to create the packages to send depends on the
number of segments that are defined in the package. Thus, the larger the number of segments, the
greater its security and the more time that the microprocessor of the device requires for generating
the package.
For the tests, smartphones have been chosen from three possible ranges, low-cost, mid-cost and
high-cost, and being several years old. The selected smartphones models are: Motorola Moto G,
Samsung Galaxy S3 and LG Nexus 5. This selection has been taken to verify the effectiveness of the
scheme on devices with limited computing capacity.
Furthermore, Android Wear smartwatches have been also used for testing, specifically the LG
G Watch and Samsung Gear Live models. Since the smartwatches depend on a smartphone, which
must be constantly connected via Bluetooth Low Energy, package generation is in fact done from
the smartphone.
Sensors 2016, 16, 75
15 of 20
Considering all of these characteristics, the programming language that has been used is Java,
because it is the most widely-used platform for programming in the Android Open Source Project.
After making dozens of experiments, the average of the results is as shown below. The time for
segment generation based on the number of nodes in the graph is shown in Figure 6.
Figure 6. Segment generation time trend
However, the results shown in Figure 6 are strongly conditioned by the process of the serialization
of graphs. In fact, this process requires much more computation time than the sum of all of the
remaining steps of the scheme. Not surprisingly, the serialization process for large graphs requires
more than 98% of the time required to build the package. The first steps of the serialization process
were much slower, more than 20 times, before the adjacency matrix was converted into hexadecimal
characters. However, after optimizing the process, it was concluded that it is more efficient to convert
it into integers using the characteristics of Java classes. The problem is that now, the occupied space is
greater than in the previous process. The computational speed has improved by a factor of 20, but
still, the process remains very slow compared to other operations of the scheme, due to the limitations
of the Java Virtual Machine. For example, for a network of 300 nodes, a graph serialization takes
about 59, 138 ms. The complete generation of a segment, including the serialization graph, takes about
60, 345 ms. These results can be substantially improved by implementing the scheme in a low-level
language that Android Open Source Project has, such as the programming language C, which is
a compiled, not interpreted, language like Java.
From the results of Figure 6, the trend has been obtained, and the associated polynomial of order
four has been calculated (see Equation (5)), which represents the number of nodes and the segment
generation time. This equation can be seen as an estimation of how long it would take to create
packages for testing, depending on the number of nodes of the graph.
y = (5E -6) x4 + (23E -4) x3 − 0.537x2 + 30.548x − 227.48
(5)
For example, in a scheme where the graph is defined by 50 nodes and the number of challenges
that defines the scheme package is six, the time to build the package is 300 ms. Thus, a mobile device
with limited capabilities could easily generate packages for the proposed scheme, as demonstrated in
these implementations.
Sensors 2016, 16, 75
16 of 20
7.4. Package Processing Time
Finally, we have analyzed the time it would take mobile devices to decipher the package that
comes from other mobile devices. These package-processing times are really short, as evidenced by
the processing time per segment shown in Figure 7.
Figure 7. Segment processing time trend.
After analyzing the above results, it was concluded that the trend of the data follows a polynomial
function of order four (see Equation (6)). This equation can be used to estimate the processing time per
segment depending on the nodes of the graph representing the network.
y = (2E -9) x5 (−1E -6) x4 + (2E -4) x3 − 0.0184x2 + 0.673x − 1.7392
(6)
This means that, for instance, a scheme in which the graph of the network is defined by 50 nodes
and the number of challenges that defines the scheme package is six, the time a mobile device takes to
process a received package to get the secret is only 48 ms.
8. Comparative Analysis
In the recent literature, it is hard to find novel schemes proposed for the authentication of mobile
devices, specifically in the Internet of Things.
Many existing research works propose lightweight authentication schemes based on challenges
and responses, but none of the proposed schemes have been implemented completely. Many authors
omit one of the most important pieces of information that can characterize a scheme of this kind:
the time required for authentication. Just a few authors have analyzed the transmission bit rate, the
percentage of packages that are lost in interactive schemes and/or the total real time that schemes
require. In this work, those parameters are studied, but the percentage of lost packages is not analyzed,
because the scheme is non-interactive and just one single message is sent, so no loss can happen.
8.1. ZKP Schemes
We have analyzed several lightweight authentication schemes applied to the Internet of
Things. For instance, [39] proposes a zero-knowledge proof authentication algorithm based on
isomorphic graphs and describes its evaluation and implementation. The proposed mechanism allows
authentication with varying confidence and security levels. Such a work describes an implementation
on conventional computers (with different configurations), so that the starting conditions are more
Sensors 2016, 16, 75
17 of 20
powerful than when using mobile devices, as in this paper, mainly because of the efficiency of the
used programming language. On the one hand, the scheme proposed in this paper uses Java as
a programming language, so that the implementation is as cross-platform as possible and, thus, can
be applied to many current mobile devices. On the other hand, the compared scheme uses random
graphs of 41 nodes. In order to allow the comparison, the scheme proposed in this paper has been also
implemented with graphs of 41 nodes. The comparison results are shown in Table 2, where the four
different hardware configurations described in the paper are shown. Another consideration is the fact
that the compared scheme uses an interactive ZKP with six exchanges of messages, while the proposal
of this paper is based on an NIZKP in which only one single message is necessary.
Table 2. Comparative data: time (ms) and size (bytes).
10 Challenges
Time
Size
Conf1. [39]
469
4045
Conf2. [39]
1302
4045
Conf3. [39]
484
4045
Conf4. [39]
1522
4045
Our Scheme
454
17,826
100 Challenges
Time
Size
3422
39,595
8070
39,595
3703
39,595
9824
39,595
5665
187,132
From Table 2, it can be concluded that the scheme that has been designed here is computationally
faster considering the average results and characteristics of both implementations. On the other hand,
the compared scheme uses fewer memory bytes. However, the relationship between memory and time
is better in the scheme proposed here than in the others. This is due to the fact that the difference in
memory space of a few kilobytes is acceptable for today’s mobile devices, both when being sent with
wireless technologies and when being stored and processed.
8.2. Schemes Based on Diffie–Hellman
Other schemes with an objective similar to that of the one proposed here have been also
compared. One of them was chosen for this study due to its popularity, frequent application and use
of Diffie–Hellman key exchange [6]. Such a method allows two parties that have no prior knowledge
of each other to jointly establish a shared secret key over an insecure communication channel, so that
this key can then be used to encrypt subsequent communications using a symmetric key cipher.
However, if no additional security measure is used, the Diffie–Hellman key exchange is vulnerable to
an MitM attack. This vulnerability is possible when Diffie–Hellman key exchange does not include the
authentication of participants. However, feasible solutions for authenticated Diffie–Hellman schemes,
such as the one proposed here, allow preventing such attacks.
After reviewing the relevant bibliography, a scheme was chosen that implements an authenticated
Diffie–Hellman protocol for the comparison. The scheme is called password authenticated key (PAK)
Diffie–Hellman exchange [40] and proposes to add mutual authentication based on a memorizable
password, to the basic, unauthenticated Diffie–Hellman key exchange. PAK allows two parties to
authenticate themselves while performing the Diffie–Hellman exchange. It also provides a secure
and authenticated key-exchange protocol, which ensures forward secrecy and is secure against offline
dictionary attacks when passwords are used.
For the comparison, the PAK scheme was implemented for Android and Android Wear devices.
Till now, the PAK scheme had not been implemented on any Android platform, so this paper provides
the first implementation of the PAK scheme in the most popular platform of mobile devices. Both
the source code of the scheme proposed in this paper and the source code for the PAK scheme have
been released as open source and are available in a hosted repository on GitHub [38]. In the tests,
the shared secret information in both schemes has been the typical ’Hello World!’ used in computer
programming environments.
Sensors 2016, 16, 75
18 of 20
In particular, in order to compare the proposed scheme with the PAK scheme, the following
configuration was used:
•
•
•
Graphs of 41 nodes, which are large enough to be considered secure in the scheme; thus, an attack
on the graph isomorphism would involve 41! iterations, which would be unfeasible.
Packages with 3, 4, 5, 6, 7 and 8 challenges.
The time for these comparisons includes both package generation by the sender and unpacking
the package by the user who receives it.
The results of the comparison are shown in Table 3. The conclusion is that in general, the scheme
proposed in this paper has a similar performance as the PAK scheme, and even in some cases, the
proposed scheme slightly improves the results of the PAK scheme.
Table 3. Password authenticated key (PAK) scheme vs. the proposed scheme.
PAK Scheme
Our Scheme
Time (ms)
Challenges
Time (ms)
197
3
4
5
6
7
8
86
112
153
176
195
221
9. Conclusions
With the proliferation of electronic devices in many areas, a new paradigm called the Internet of
Things has emerged. One of the biggest threats to the deployment of the networks involved in the
Internet of Things is the security of communications, so new lightweight cryptographic algorithms
that are adapted to the computing capabilities of mobile devices are necessary. In this paper, a novel
scheme based on the idea of non-interactive zero-knowledge proofs is presented. The proposal only
requires sending a message to share confidential information in an authenticated way. Thus, the new
algorithm is proposed to be used for establishing authenticated secret session keys between pairs
of legitimate nodes of mobile ad hoc networks. Furthermore, the scheme can be used by nodes that
want to send authenticated information in broadcast mode to other legitimate nodes in the network.
Different use cases are defined for the authenticated public key exchange in these networks by using
variants of the scheme described in this paper. The proposal is mainly characterized by not using
interaction for authentication, which is very adequate for volatile networks, such as those in the
Internet of Things, which require a more efficient authentication procedure. The scheme has been
implemented for the platforms under the seal of the Android Open Source Project, and the design has
been optimized to reach a high level of security at a low cost of memory consumption. The obtained
results are promising, as they improve the performance of other lightweight authentication schemes
based on zero knowledge proofs. Several open problems still remain and could be solved in future
work, such as the design of an improved service system based on the proposal.
Acknowledgments: Research supported by TIN2011-25452, BES-2012-051817, IPT-2012-0585-370000,
RTC-2014-1648-8 and TEC2014-54110-R.
Author Contributions: Francisco Martín-Fernández and Pino Caballero-Gil conceived the authentication protocol
and algorithms and wrote the paper. Francisco Martín-Fernández developed the algorithms in the Android
Open Source Project. Francisco Martín-Fernández and Cándido Caballero-Gil designed and performed the
experiments, analyzed the data and produced the result graphical material. All authors revised the paper for
intellectual content.
Conflicts of Interest: The authors declare no conflict of interest.
Sensors 2016, 16, 75
19 of 20
References
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
Katagi, M.; Moriai, S. Lightweight Cryptography for the Internet of Things. Available online:
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.227.8445&rep=rep1&type=pdf (accessed on 6
January 2016).
Velev, D.G. Internet of Things âĂŞ Analysis and Challenges. UNWE Econ. Altern. 2011, 2, 99–109.
Cirani, S.; Ferrari, G.; Veltri, L. Enforcing Security Mechanisms in the IP-Based Internet of Things: An
Algorithmic Overview. Algorithms Spec. Issue Sens. Netw. 2013, 6, 197–226.
Diffie, W.; Van Oorschot, P.C.; Wiener, M.J. Authentication and authenticated key exchanges. Des. Codes
Cryptogr. 1992, 2, 107–125.
Chan, H.; Perrig, A.; Song, D. Random key predistribution schemes for sensor networks. IEEE Symp. Secur.
Priv. 2003, doi:10.1109/SECPRI.2003.1199337.
Diffie, W.; Hellman, M.E. New directions in cryptography. IEEE Trans. Inf. Theory 1976, 22, 644–654.
Chan, A.C.F. Distributed symmetric key management for mobile ad hoc networks. In Proceeding of the
Twenty-third AnnualJoint Conference of the IEEE Computer and Communications Societies, HongKong,
China, 7–11 March 2004; pp. 2414–2424.
Capkun, S.; Buttyan, L.; Hubaux, J.P. Self-organized public-key management for mobile ad hoc networks.
IEEE Trans. Mob. Comput. 2003, 2, 52–64.
Atzori, L.; Iera, A.; Morabito, G. The Internet of Things: A survey. Comput. Netw. 2010, 54, 2787–2805.
Goldwasser, S.; Micali, S.; Rivest, R.L. A digital signature scheme secure against adaptive chosen-message
attacks. SIAM J. Comput. 1988, 17, 281–308.
Maurer, U. Modelling a public-key infrastructure. Comput. Secur. ESORICS 1996, 96, 325–350.
Caballero-Gil, P.; Hernández-Goya, C. Efficient public key certificate management for mobile ad hoc networks.
EURASIP J. Wirel. Commun. Netw. 2011, doi:10.1155/2011/935457.
Goldwasser, S.; Micali, S.; Rackoff, C. The knowledge complexity of interactive proof systems. ACM Symp.
Theory Comput. 1985, doi:10.1145/22145.22178.
Feige, U.; Fiat, A.; Shamir, A. Zero-knowledge proofs of identity. J. Cryptol. 1988, 1, 77–94.
Blum, M.; Feldman, P.; Micali, S. Non-interactive zero-knowledge and its applications. ACM Symp. Theory
Comput. 1988, doi:10.1145/62212.62222.
Rackoff, C.; Simon, D.R. Non-interactive zero-knowledge proof of knowledge and chosen ciphertext attack.
In Advances in Cryptology; Feigenbaum, J., Ed.; Springer: Berlin, Gernamy, 1992; Volume 576, pp. 433–444.
Fiat, A.; Shamir, A. How to prove yourself: Practical solutions to identification and signature problems. In
Advances in Cryptology; Odlyzko, A.M., Ed.; Springer: Berlin, Gernamy, 1987; Volume 263, pp. 186–194.
Feige, U.; Lapidot, D.; Shamir, A. Multiple non-interactive zero knowledge proofs randomstring. In
Proceedings of the 31st Annual Symposium on Foundations of Computer Science, St. Louis, MO, USA,
22–24 October 1990; pp. 308–317.
Bellare, M.; Yung, M. Certifying cryptographic tools: The case of trapdoor permutations. In Advances in
Cryptology; Brickell, E.F., Ed.; Springer: Berlin, Gernamy, 1992.
Lapidot, D.; Shamir, A. Publicly verifiable non-interactive zero-knowledge proofs. In Advances in Cryptology;
Menezes, A.J., Vanstone, S.A., Eds.; Springer: Berlin, Gernamy, 1990; Volume 537, pp. 353–365.
Goldreich, O.; Micali, S.; Wigderson, A. Proofs that yield nothing but their validity or all languages in NP
have zero-knowledge proof systems. J. ACM 1991, 38, 690–728.
Goldwasser, S.; Micali, S.; Rackoff, C. The knowledge complexity of interactive proof systems. SIAM J.
Comput. 1989, 18, 186–208.
Garey, M.R.; Johnson, D.S. Computers and Intractability: A Guide the theory of NP-Completeness. Available
on: http://dl.acm.org/citation.cfm?id=574848 (accessed on 6 January 2016).
Bertoni, G.; Daemen, J.; Peeters, M.; Van Assche, G. Keccak sponge function family main document.
Available online: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.419.2140&rep=rep1&type=pdf
(accessed on 6 January 2016).
Bertoni, G.; Daemen, J.; Peeters, M.; Van Assche, G. The Keccak SHA-3 submission. Available online:
http://keccak.noekeon.org/Keccak-submission-3.pdf (accessed on 6 January 2016).
Ekdahl, P.; Johansson, T. SNOW - a new stream cipher. Available online: http://www.madchat.fr/
crypto/hash-lib-algo/snow/snow10.pdf (accessed on 6 January 2016).
Sensors 2016, 16, 75
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
20 of 20
ETSI/SAGE; Specification of the 3GPP Confidentiality and Integrity Algorithms UEA2 and UIA2. Document
2. Available online: http://www.3gpp.org/DynaReport/35-series.htm (accessed on 6 January 2016).
Ekdahl, P.; Johansson, T. A New Version of the Stream Cipher SNOW. In Selected Areas in Cryptography;
Nyberg, K., Heys, H., Eds.; Springer: Berlin, Germany, 2003; Volume 2595, pp. 37–46.
Roman, R.; Zhou, J.; Lopez, J. On the features and challenges of security and privacy in distributed internet
of things. Comput. Netw. 2013, 57, 2266–2279.
Lin, X.; Lu, R.; Zhang, C.; Zhu, H.; Ho, P.; Shen, X. Security in Vehicular Ad Hoc Networks. IEEE Commun.
Mag. 2008, 46, 88–95.
Martín-Fernández, F.; Caballero-Gil, P.; Caballero-Gil, C. Detection and Report of Traffic Lights Violation
using Sensors and Smartphones. In Ubiquitous Computing and Ambient Intelligence. Sensing, Processing, and
Using Environmental Information; García-Chamizo, J.M., Fortino, G., Ochoa, S.F., Eds.; Springer: Berlin,
Germany, 2015; Volume 9454, pp. 237–248.
Barker, E.; Barker, W.; Burr, W.; Polk, W.; Smid, M. Computer Security.
Available online:
http://csrc.nist.gov/publications/nistpubs/800-57/sp800-57-Part1-revised2_Mar08-2007.pdf (accessed on 6
January 2016).
Bertoni, G.; Daemen, J.; Peeters, M.; Van Assche, G. On the Indifferentiability of the Sponge Construction. In
Advances in Cryptology; Smart, N., Ed.; Springer, Berlin, Germany, 2008; Volume 4965, pp. 181–197.
Andreeva, E.; Mennink, B.; Preneel, B. Security Reductions of the Second Round SHA-3 Candidates. In
Information Security; Burmester, M., Tsudik, G., Magliveras, S., Ilić, I., Eds.; Springer, Berlin, Germany, 2010;
Volume 6531, pp. 39–53.
Kircanski, A. Cryptanalysis of Symmetric Cryptographic Primitives.
Available online:
https://www.iacr.org/phds/125_AleksandarKircanski_CryptanalysisSymmetricCryptogr.pdf (accessed
on 6 January 2016).
Babai, L.; Erdos, P.; Selkow S.M. Random graph isomorphism. SIAM J. Comput. 1980, 9, 628–635.
Corneil, D.G.; Gotlieb, C.C. An efficient algorithm for graph isomorphism. J. ACM 1970, 17, 51–64.
Martín-Fernández, F. Source Code of The Authenticated Scheme Proposed.
Available online:
https://github.com/pacomf/ASD (accessed on 6 January 2016).
Grzonkowski, S.; Zaremba, W.; Zaremba, M.; McDaniel, B. Extending Web Applications with a Lightweight
Zero Knowledge Proof Authentication. In Proceedings of the 5th international conference on Soft computing
as transdisciplinary science and technology, New York, NY, USA, 28–31 October 2008; pp. 65–70.
Brusilovsky, A.; Faynberg, I.; Zeltsan, Z.; Patel, S. Password-Authenticated Key (PAK) Diffie-Hellman
Exchange. Available online: http://www.rfc-editor.org/info/rfc5683 (accessed on 6 January 2016).
c 2016 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons by Attribution
(CC-BY) license (http://creativecommons.org/licenses/by/4.0/).
|
|
https://openalex.org/W2895353487
|
https://www.mdpi.com/2073-4344/8/10/432/pdf?version=1538302481
|
English
| null |
A Novel Method for the Prediction of Erosion Evolution Process Based on Dynamic Mesh and Its Applications
|
Catalysts
| 2,018
|
cc-by
| 12,654
|
Received: 29 August 2018; Accepted: 28 September 2018; Published: 30 September 2018 Received: 29 August 2018; Accepted: 28 September 2018; Published: 30 September 2018 Abstract: Particle erosion is a commonly occurring phenomenon, and it plays a significantly
important role in service life. However, few simulations have replicated erosion, especially the
detailed evolution process. To address this complex issue, a new method for establishing the solution
of the erosion evolution process was developed. The approach is introduced with the erosion model
and the dynamic mesh. The erosion model was applied to estimate the material removal of erosion,
and the dynamic mesh technology was used to demonstrate the surface profile of erosion. Then,
this method was applied to solve a typical case—the erosion surface deformation and the expiry
period of an economizer bank in coal-fired power plants. The mathematical models were set up,
including gas motion, particle motion, particle-wall collision, and erosion. Such models were solved
by computational fluid dynamics (CFD) software (ANSYS FLUENT), which describes the evolution
process of erosion based on the dynamic mesh. The results indicate that: (1) the prediction of
the erosion profile calculated by the dynamic mesh is in good agreement with that on-site; (2) the
global/local erosion loss and the maximum erosion depth is linearly related to the working time at
the earlier stage, but the growth of the maximum erosion depth slows down gradually in the later
stage; (3) the reason for slowing down is that the collision point trajectory moves along the increasing
direction of the absolute value of θ as time increases; and (4) the expiry period is shortened as the ash
diameter increases. Keywords: erosion evolution; erosion rate; dynamic mesh; CFD; economizer; expiry period A Novel Method for the Prediction of Erosion
Evolution Process Based on Dynamic Mesh and
Its Applications Yunshan Dong 1, Zongliang Qiao 1, Fengqi Si 1,*, Bo Zhang 1,*, Cong Yu 1 and Xiaom Yunshan Dong , Zongliang Qiao , Fengqi Si
, Bo Zhang
, Cong Yu
and Xiaoming Jiang
1
Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and
Environment, Southeast University, Nanjing 210096, China; ysh_dong@126.com (Y.D.);
qiaozongliang@seu.edu.cn (Z.Q.); congy@seu.edu.cn (C.Y.)
2
Datang Nanjing Environmental Protection Technology Co., Ltd., Nanjing 211100, China;
jiangxm@dteg.com.cn 1
Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and
Environment, Southeast University, Nanjing 210096, China; ysh_dong@126.com (Y.D.);
qiaozongliang@seu.edu.cn (Z.Q.); congy@seu.edu.cn (C.Y.)
2
Datang Nanjing Environmental Protection Technology Co., Ltd., Nanjing 211100, China; 1
Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and
Environment, Southeast University, Nanjing 210096, China; ysh_dong@126.com (Y.D.);
qiaozongliang@seu.edu.cn (Z.Q.); congy@seu.edu.cn (C.Y.)
2
Datang Nanjing Environmental Protection Technology Co Ltd Nanjing 211100 China; j
g
g
*
Correspondence: fqsi@seu.edu.cn (F.S.); bozhang@seu.edu.cn (B.Z.) *
Correspondence: fqsi@seu.edu.cn (F.S.); bozhang@seu.edu.cn (B.Z.) catalysts catalysts catalysts 1. Introduction Erosion is mechanical damage resulting from the impact of particles carried by fluid [1]. When a
particle with a certain speed strikes a solid surface, the impact region of the surface will be deformed [2–4]. Subsequently, the surface deformation translates into material removal, which shortens the service life,
such as the SCR (selective catalytic reduction) catalyst and the economizer in Figure 1, among others. Erosion is a complex problem caused by numerous factors, such as particle velocity, impact angle,
particle size, and particle shape. Catalysts 2018, 8, 432; doi:10.3390/catal8100432 www.mdpi.com/journal/catalysts 2 of 16 Catalysts 2018, 8, 432
Catalysts 201 (b) (a)
(b)
Figure 1. Particle erosion. (a) SCR catalyst; (b) economizer (reprinted with permission from reference
[5]. Copyright 2018 ELSEVIER). Figure 1. Particle erosion. (a) SCR catalyst; (b) economizer (reprinted with permission from
reference [5]. Copyright 2018 ELSEVIER). (a) (b) (a) Figure 1. Particle erosion. (a) SCR catalyst; (b) economizer (reprinted with permission from reference
[5]. Copyright 2018 ELSEVIER). Figure 1. Particle erosion. (a) SCR catalyst; (b) economizer (reprinted with permission from
reference [5]. Copyright 2018 ELSEVIER). Considerable studies have been performed on erosion. Finnie [6,7] and Bitter et al. [8,9]
presented the earliest work focusing on theoretical erosion mechanism. Finnie’s erosion model was
based on the experimental phenomenon of erosion and the models of the micro-cutting mechanism. However, at the impact angle of 90°, it predicted no erosion rate at all, and the analyzed data clearly
indicated that it is incorrect. Bitter’s erosion model was proposed with respect to deformation and
cutting wear, despite lacking the support of any physical models. Huang et al. [10] addressed these
shortages, deriving a phenomenological erosion model by analyzing the normal and tangential
forces acting on the abrasive particle. Huang’s erosion model has been increasingly acknowledged
by researchers. In addition to the theoretical erosion model, numerous erosion equations have been
developed based on experimental tests. Most of these erosion equations have been presented
regarding the function of the velocity exponent and the impact angle. Grant and Tabakoff [11]
developed an empirical erosion equation. This model pointed out that the coefficient of restitution
should be incorporated into the equation, owing to multiple times of impingement by the particle. Okal et al. [12,13] conducted erosion tests for a wide range of materials and erodent particles,
considering both material hardness and the load relaxation ratio. 1. Introduction Many parameters were involved in
this model, although the parameters are hard to acquire. Besides these, Haugen [14], Ahlert [15],
Mclaury [16], and Zhang [17] at E/CRC of the University of Tulsa also proposed different empirical
erosions, and Shamshirband et al. [18] adapted the ANFIS (adaptive neuro-fuzzy inference system,
a type of neural network) model to precisely predict the total and maximum erosion rate. The aforementioned work focused on the erosion ratio. However, the evolution process of
erosion has been little studied in the research, mainly because no methods or models have described
long periods of erosion or shape evolution, except for the experiments. However, such experiments
take too much time and material power. If feasible methods or models were available to describe the
evolution process, the research would make progress. In this study the material removal of erosion was investigated by CFD (computational fluid
Considerable studies have been performed on erosion. Finnie [6,7] and Bitter et al. [8,9] presented
the earliest work focusing on theoretical erosion mechanism. Finnie’s erosion model was based on the
experimental phenomenon of erosion and the models of the micro-cutting mechanism. However, at the
impact angle of 90◦, it predicted no erosion rate at all, and the analyzed data clearly indicated that it is
incorrect. Bitter’s erosion model was proposed with respect to deformation and cutting wear, despite
lacking the support of any physical models. Huang et al. [10] addressed these shortages, deriving a
phenomenological erosion model by analyzing the normal and tangential forces acting on the abrasive
particle. Huang’s erosion model has been increasingly acknowledged by researchers. In addition to the
theoretical erosion model, numerous erosion equations have been developed based on experimental
tests. Most of these erosion equations have been presented regarding the function of the velocity
exponent and the impact angle. Grant and Tabakoff [11] developed an empirical erosion equation. This model pointed out that the coefficient of restitution should be incorporated into the equation,
owing to multiple times of impingement by the particle. Okal et al. [12,13] conducted erosion tests
for a wide range of materials and erodent particles, considering both material hardness and the load
relaxation ratio. Many parameters were involved in this model, although the parameters are hard
to acquire. Besides these, Haugen [14], Ahlert [15], Mclaury [16], and Zhang [17] at E/CRC of the
University of Tulsa also proposed different empirical erosions, and Shamshirband et al. 1. Introduction [18] adapted
the ANFIS (adaptive neuro-fuzzy inference system, a type of neural network) model to precisely
predict the total and maximum erosion rate. In this study, the material removal of erosion was investigated by CFD (computational fluid
dynamics software) coupled with the UDF (user defined function) of the particle motion and erosion
model. It is worth highlighting that the detailed evolution process of erosion will be realized by the
dynamic mesh technique. This DPM (discrete phase model) approach, coupling the erosion model
and dynamic mesh, combines the material removal and the mesh deformation quantitatively, which
can demonstrate the node displacement of the mesh in the erosion region and the new flow field. Accordingly the flow field and the particle trajectory are transformed at all times Based on those
The aforementioned work focused on the erosion ratio. However, the evolution process of erosion
has been little studied in the research, mainly because no methods or models have described long
periods of erosion or shape evolution, except for the experiments. However, such experiments take too
much time and material power. If feasible methods or models were available to describe the evolution
process, the research would make progress. Accordingly, the flow field and the particle trajectory are transformed at all times. Based on those
concepts, the evolution of the erosion loss and erosion depth was investigated by the CFD-DPM
approach firstly. The erosion profile was achieved secondly. Moreover, this paper applies the method to discuss the expiry period of the economizer in
modern coal-fired power plants. The economizer is used to improve the overall thermal efficiency in
the gas-water exchangers, exacting residual heat energy from the flue gas and transferring the
In this study, the material removal of erosion was investigated by CFD (computational fluid
dynamics software) coupled with the UDF (user defined function) of the particle motion and erosion
model. It is worth highlighting that the detailed evolution process of erosion will be realized by
the dynamic mesh technique. This DPM (discrete phase model) approach, coupling the erosion
model and dynamic mesh, combines the material removal and the mesh deformation quantitatively,
which can demonstrate the node displacement of the mesh in the erosion region and the new flow
field. Accordingly, the flow field and the particle trajectory are transformed at all times. Based on
those concepts, the evolution of the erosion loss and erosion depth was investigated by the CFD-DPM
approach firstly. 2. Method Description
fatigue, thermal fatigu
Among these ash ero Figure 2 demonstrates the calculative process of erosion evolution. The process includes the flow
calculation, particle tracking, material removal calculation coupled with the UDF of the erosion model,
erosion profile calculation with the UDF of the dynamic mesh, and the ALE (arbitrary Lagrange–Euler)
calculation. ANSYS FLUENT calculates the trajectory of the discrete particle by integrating the
force balance on the particle, which is done in the Lagrangian frame. Then, the collision point of the
particle-wall collision is tracked, and the particle-wall collision is translated into the material removal in
the UDF of the erosion model. Then, the material removal is converted to wall-mesh deformation in the
UDF of the dynamic mesh. Dynamic mesh is universally applied for the fluid–structure interaction [21],
flapping flight [22] and so forth. However, this dynamic mesh technology is rarely introduced to the
erosion profile that is formed by wall-mesh deformation. Figure 3 shows the mesh deformation before
and after the particle-wall collision by the dynamic mesh. The value of the material removal is stored
in the center of the boundary mesh. However, the dynamic mesh moves the node of the boundary
mesh, and the value in the node is interpolated by the value in the center. In this interpolation, this
paper keeps the elementary volume constant, as follows:
g
,
p y
g
y
p
p y p
Therefore, this work will benefit the design of the economizer and guide the boiler operation. 2. Method Description
Figure 2 demonstrates the calculative process of erosion evolution. The process includes the
flow calculation, particle tracking, material removal calculation coupled with the UDF of the erosion
model, erosion profile calculation with the UDF of the dynamic mesh, and the ALE (arbitrary
Lagrange–Euler) calculation. ANSYS FLUENT calculates the trajectory of the discrete particle by
integrating the force balance on the particle, which is done in the Lagrangian frame. Then, the
collision point of the particle-wall collision is tracked, and the particle-wall collision is translated
into the material removal in the UDF of the erosion model. Then, the material removal is converted
to wall-mesh deformation in the UDF of the dynamic mesh. Dynamic mesh is universally applied for
the fluid–structure interaction [21], flapping flight [22] and so forth. However, this dynamic mesh
technology is rarely introduced to the erosion profile that is formed by wall-mesh deformation. 2. Method Description
fatigue, thermal fatigu
Among these ash ero Figure 3 shows the mesh deformation before and after the particle-wall collision by the dynamic
mesh. The value of the material removal is stored in the center of the boundary mesh. However, the
d
i
h
th
d
f th b
d
h
d th
l
i
th
d i i t
l t d b th hi,j =
1/4∆t
1
∑
k=0
1
∑
l=0
Qn
i−1/2+k,j−1/2+l
1/4ρm
1
∑
k=0
1
∑
l=0
An−1
i−1/2+k,j−1/2+l
(1)
de of the boundary mesh, and the value in the node is interpolated by the
erpolation, this paper keeps the elementary volume constant, as follows:
∑∑
∑∑
−
+
+
=
=
+
−
+
−
=
1
1
1
2
/
1
2
/
1
1
0
1
0
2
/
1
,
2
/
1
,
4
/
1
4
/
1
n
l
j
k
i
k
l
n
l
j
k
i
j
i
A
Q
t
h
ρ
∆
(1) (1) Qi−1/2,j−1/2 is the rate of the material removal, the function of the particle mass flow rate mp
and the erosion rate Er in the [i −1/2, j −1/2] element mesh; Ai−1/2,j−1/2 is the area of the [i −1/2,
j −1/2] element mesh; n is the time step; ∆t is the time step size. ∑∑
=
=
0
0
,
k
l
j
2
/
1
,2
/
1
−
−
j
i
Q
is the rate of the material removal, the function of the particle mass flow rate
p
m
and the erosion rate
r
E in the [
2
/
1
−
i
,
2
/
1
−
j
] element mesh;
2
/
1
,2
/
1
−
−
j
iA
is the area of the [
2
/
1
−
i
, Qi−1/2,j−1/2 is the rate of the material removal, the function of the particle mass flow rate mp
and the erosion rate Er in the [i −1/2, j −1/2] element mesh; Ai−1/2,j−1/2 is the area of the [i −1/2,
j −1/2] element mesh; n is the time step; ∆t is the time step size. 1. Introduction The erosion profile was achieved secondly. Moreover, this paper applies the method to discuss the expiry period of the economizer in modern
coal-fired power plants. The economizer is used to improve the overall thermal efficiency in the
gas-water exchangers, exacting residual heat energy from the flue gas and transferring the energy to
the feed water [19]. However, the flue gas includes ash particles, corrosive gas, temperature oscillation, 3 of 16 Catalysts 2018, 8, 432 and so on. Those factors respectively contribute to ash erosion, corrosion fatigue, thermal fatigue,
and so forth, which may ultimately lead to bursting of economizer tubes [20]. Among these, ash erosion
plays a significantly important role in the expiry period of the economizer. Therefore, this work will
benefit the design of the economizer and guide the boiler operation. Catalysts 2018, 8, x FOR PEER REVIEW
3 of 17
energy to the feed water [19]. However, the flue gas includes ash particles, corrosive gas,
temperature oscillation and so on Those factors respectively contribute to ash erosion corrosion 2. Method Description
fatigue, thermal fatigu
Among these ash ero ∑∑
=
=
0
0
k
l
j
2
/
1
,2
/
1
−
−
j
i
Q
is the rate of the material removal, the function of the particle mass flow rate
p
m
and the erosion rate
r
E in the [
2
/
1
−
i
,
2
/
1
−
j
] element mesh;
2
/
1
,2
/
1
−
−
j
iA
is the area of the [
2
/
1
−
i
, The ALE calculation is used to correct the flux after the mesh deformation. In the ALE description,
the nodes of the computational mesh may be moved with the continuum in a normal Lagrangian fashion,
or be held fixed in a Eulerian manner [23,24]. At last, this paper adopts the unsteady calculation, and
the erosion effect of the time step amounts to 1day. It is possible to regard the erosion rate Er as the
constant during 1day. Additionally, when computation time t is at the maximum time tmax (2 years in
this paper) given, the calculation is terminated. 2
/
1
−
j
] element mesh; n is the time step;
t
∆ is the time step size. The ALE calculation is used to correct the flux after the mesh deformation. In the ALE
description, the nodes of the computational mesh may be moved with the continuum in a normal
Lagrangian fashion, or be held fixed in a Eulerian manner [23,24]. At last, this paper adopts the
unsteady calculation, and the erosion effect of the time step amounts to 1day. It is possible to regard
the erosion rate
r
E as the constant during 1day. Additionally, when computation time t is at the
maximum time t
(2 years in this paper) given the calculation is terminated y
p p
) g
Initial t=0
Flow
calculation
Particle track
Material removal
calculation
Erosion profile
calculation
t<tmax
Next t
End
UDF of erosion
model
UDF of
dynamic mesh
ALE calculation
Figure 2. Calculativeprocess of erosion evolution. Figure 2. Calculativeprocess of erosion evolution. UDF of erosion
model Material removal
calculation Figure 2. Calculativeprocess of erosion evolution. Figure 2. Calculativeprocess of erosion evolution. 2. Method Description
fatigue, thermal fatigu
Among these ash ero Catalysts 2018, 8, 432
Catalysts 2018, 8, x F 4 of 16
4 of 1 1
1
,1
−
+
−
n
j
i
Q
1
1
,
−
+
n
j
i
Q
1
1
,1
−
+
+
n
j
i
Q
1
,1
−
−
n
j
i
Q
1
,
−
n
j
i
Q
1
,1
−
+
n
j
i
Q
1
1
,
1
−
−
−
n
j
i
Q
1
1
,
−
−
n
j
i
Q
1
1
,1
−
−
+
n
j
i
Q
1
2
/1
,2
/1
−
+
−
n
j
i
Q
1
2
/1
,2
/1
−
+
+
n
j
i
Q
1
2
/1
,2
/1
−
−
−
n
j
i
Q
1
2
/1
,2
/1
−
−
+
n
j
i
Q
n
j
i
Q ,
n
j
i
Q
2
/
1
,2
/
1
+
−
n
j
i
Q
2
/
1
,
2
/
1
+
+
n
j
i
Q
2
/
1
,2
/
1
−
−
n
j
i
Q
2
/
1
,2
/
1
−
+
new wall
original wall
first boundary layer
(b)
1
1
,1
−
+
−
n
j
i
Q
1
1
,
−
+
n
j
i
Q
1
1
,1
−
+
+
n
j
i
Q
1
,1
−
−
n
j
i
Q
1
,
−
n
j
i
Q
1
,1
−
+
n
j
i
Q
1
1
,
1
−
−
−
n
j
i
Q
1
1
,
−
−
n
j
i
Q
1
1
,1
−
−
+
n
j
i
Q
1
2
/1
,2
/1
−
+
−
n
j
i
Q
1
2
/1
,2
/1
−
+
+
n
j
i
Q
1
2
/1
,2
/1
−
−
−
n
j
i
Q
1
2
/1
,2
/1
−
−
+
n
j
i
Q
n
j
i
Q ,
n
j
i
Q
2
/
1
,2
/
1
+
−
n
j
i
Q
2
/
1
,
2
/
1
+
+
n
j
i
Q
2
/
1
,2
/
1
−
−
n
j
i
Q
2
/
1
,2
/
1
−
+
new wall
original wall
first boundary layer
(b)
mic mesh: (a) before collision; (b) after collision. 2. Method Description
fatigue, thermal fatigu
Among these ash ero 1
1
,1
−
+
−
n
j
i
Q
1
1
,
−
+
n
j
i
Q
1
1
,1
−
+
+
n
j
i
Q
1
,1
−
−
n
j
i
Q
1
,
−
n
j
i
Q
1
,1
−
+
n
j
i
Q
1
1
,1
−
−
−
n
j
i
Q
1
1
,
−
−
n
j
i
Q
1
1
,1
−
−
+
n
j
i
Q
1
2
/1
,2
/1
−
+
−
n
j
iQ
1
2
/1
,2
/1
−
+
+
n
j
iQ
1
2
/1
,2
/1
−
−
−
n
j
i
Q
1
2
/1
,2
/1
−
−
+
n
j
iQ
wall
first boundary layer
1
1
,1
−
+
−
n
j
i
Q
1
1
,
−
+
n
j
i
Q
1
1
,1
−
+
+
n
j
i
Q
1
,1
−
−
n
j
i
Q
1
,
−
n
j
i
Q
1
,1
−
+
n
j
i
Q
1
1
,
1
−
−
−
n
j
i
Q
1
1
,
−
−
n
j
i
Q
1
1
,1
−
−
+
n
j
i
Q
1
2
/1
,2
/1
−
+
−
n
j
i
Q
1
2
/1
,2
/1
−
+
+
n
j
i
Q
1
2
/1
,2
/1
−
−
−
n
j
i
Q
1
2
/1
,2
/1
−
−
+
n
j
i
Q
n
j
i
Q ,
n
j
i
Q
2
/
1
,2
/
1
+
−
n
j
i
Q
2
/
1
,
2
/
1
+
+
n
j
i
Q
2
/
1
,2
/
1
−
−
n
j
i
Q
2
/
1
,2
/
1
−
+
new wall
original wall
first boundary layer
(a)
(b)
Figure 3. Erosion profile calculation with dynamic mesh: (a) before collision; (b) after collision. Figure 3. Erosion profile calculation with dynamic mesh: (a) before collision; (b) after collision. 2. Method Description
fatigue, thermal fatigu
Among these ash ero 1
1
,1
−
+
−
n
j
i
Q
1
1
,
−
+
n
j
i
Q
1
1
,1
−
+
+
n
j
i
Q
1
,1
−
−
n
j
i
Q
1
,
−
n
j
i
Q
1
,1
−
+
n
j
i
Q
1
1
,1
−
−
−
n
j
i
Q
1
1
,
−
−
n
j
i
Q
1
1
,1
−
−
+
n
j
i
Q
1
2
/1
,2
/1
−
+
−
n
j
iQ
1
2
/1
,2
/1
−
+
+
n
j
iQ
1
2
/1
,2
/1
−
−
−
n
j
i
Q
1
2
/1
,2
/1
−
−
+
n
j
iQ
wall
first boundary layer
1
1
,1
−
+
−
n
j
i
Q
1
1
,
−
+
n
j
i
Q
1
1
,1
−
+
+
n
j
i
Q
1
,1
−
−
n
j
i
Q
1
,
−
n
j
i
Q
1
,1
−
+
n
j
i
Q
1
1
,1
−
−
−
n
j
i
Q
1
1
,
−
−
n
j
i
Q
1
1
,1
−
−
+
n
j
i
Q
1
2
/1
,2
/1
−
+
−
n
j
iQ
1
2
/1
,2
/1
−
+
+
n
j
iQ
1
2
/1
,2
/1
−
−
−
n
j
i
Q
1
2
/1
,2
/1
−
−
+
n
j
iQ
wall
first boundary layer (b)
( )
sion; ( (a)
)
on pr Figure 3. Erosion profile calculation with dynamic mesh: (a) before collision; (b) after collision
Figure 3. Erosion profile calculation with dynamic mesh: (a) before collision; (b) after collision. Figure 3. Erosion profile calculation with dynamic mesh: (a) before collision; (b) after collision. When the erosion profile is transformed, the flow field, especially the boundary layer, will b
changed also. The specific mathematical relation between the material removal and the wall-mes
deformation is in Formula (1). The wall-mesh deformation leads conversely to the modification o
the particle trajectory. This is the coupled calculation of multi-physics, including the flow, particl
motion, and erosion. When the erosion profile is transformed, the flow field, especially the boundary layer, will be
changed also. 3 1 1 Flow Configuration
3.1.1. Flow Configuration
3.1.1. Flow Configuration 3.1.1. Flow Configuration
The economizer of a 600MW coal-fired power plant was studied in this work. It is composed o
135 rows of S-shaped circular tubes and made from SA 210 GRA1(N); the other detailed parameter
are shown in Table 1. Considering the periodic distribution of the tube bank in Figure 4, this pape
t k
th
h d d
i
th
h
it
The economizer of a 600MW coal-fired power plant was studied in this work. It is composed of
135 rows of S-shaped circular tubes and made from SA 210 GRA1(N); the other detailed parameters
are shown in Table 1. Considering the periodic distribution of the tube bank in Figure 4, this paper
takes the shaded region as the research unit. The economizer of a 600MW coal-fired power plant was studied in this work. It is composed of
135 rows of S-shaped circular tubes and made from SA 210 GRA1(N); the other detailed parameters
are shown in Table 1. Considering the periodic distribution of the tube bank in Figure 4, this paper
takes the shaded region as the research unit. takes the shaded region as the research unit. Figure 5 gives the three-dimensional diagram of the research unit and the boundary conditions
Boundary conditions were set as follows: velocity-inlet, pressure-outlet, and wall. As mentioned
earlier, there exists periodicity in the Y direction. Meanwhile, along the tube (Z direction), the flow i
similar Thus the periodic boundary is loaded onto the Y direction and the Z direction
Figure 5 gives the three-dimensional diagram of the research unit and the boundary conditions. Boundary conditions were set as follows: velocity-inlet, pressure-outlet, and wall. As mentioned
earlier, there exists periodicity in the Y direction. Meanwhile, along the tube (Z direction), the flow is
similar. Thus, the periodic boundary is loaded onto the Y direction and the Z direction. Figure 5 gives the three-dimensional diagram of the research unit and the boundary conditions. Boundary conditions were set as follows: velocity-inlet, pressure-outlet, and wall. As mentioned
earlier, there exists periodicity in the Y direction. Meanwhile, along the tube (Z direction), the flow is
similar. Thus, the periodic boundary is loaded onto the Y direction and the Z direction. 3. Application
3. Application
3. Application 3.1. Mathematical Mode
3.1. Mathematical Model
3.1. Mathematical Model 2. Method Description
fatigue, thermal fatigu
Among these ash ero The specific mathematical relation between the material removal and the wall-mesh
deformation is in Formula (1). The wall-mesh deformation leads conversely to the modification of the
particle trajectory. This is the coupled calculation of multi-physics, including the flow, particle motion,
and erosion. When the erosion profile is transformed, the flow field, especially the boundary layer, will be
changed also. The specific mathematical relation between the material removal and the wall-mesh
deformation is in Formula (1). The wall-mesh deformation leads conversely to the modification of
the particle trajectory. This is the coupled calculation of multi-physics, including the flow, particle
motion, and erosion. 2. Method Description
fatigue, thermal fatigu
Among these ash ero 1
1
,1
−
+
−
n
j
i
Q
1
1
,
−
+
n
j
i
Q
1
1
,1
−
+
+
n
j
i
Q
1
,1
−
−
n
j
i
Q
1
,
−
n
j
i
Q
1
,1
−
+
n
j
i
Q
1
1
,1
−
−
−
n
j
i
Q
1
1
,
−
−
n
j
i
Q
1
1
,1
−
−
+
n
j
i
Q
1
2
/1
,2
/1
−
+
−
n
j
iQ
1
2
/1
,2
/1
−
+
+
n
j
iQ
1
2
/1
,2
/1
−
−
−
n
j
i
Q
1
2
/1
,2
/1
−
−
+
n
j
iQ
wall
first boundary layer
1
1
,1
−
+
−
n
j
i
Q
1
1
,
−
+
n
j
i
Q
1
1
,1
−
+
+
n
j
i
Q
1
,1
−
−
n
j
i
Q
1
,
−
n
j
i
Q
1
,1
−
+
n
j
i
Q
1
1
,
1
−
−
−
n
j
i
Q
1
1
,
−
−
n
j
i
Q
1
1
,1
−
−
+
n
j
i
Q
1
2
/1
,2
/1
−
+
−
n
j
i
Q
1
2
/1
,2
/1
−
+
+
n
j
i
Q
1
2
/1
,2
/1
−
−
−
n
j
i
Q
1
2
/1
,2
/1
−
−
+
n
j
i
Q
n
j
i
Q ,
n
j
i
Q
2
/
1
,2
/
1
+
−
n
j
i
Q
2
/
1
,
2
/
1
+
+
n
j
i
Q
2
/
1
,2
/
1
−
−
n
j
i
Q
2
/
1
,2
/
1
−
+
new wall
original wall
first boundary layer
(a)
(b)
Figure 3. Erosion profile calculation with dynamic mesh: (a) before collision; (b) after collision. 3 1 1 Flow Configuration
3.1.1. Flow Configuration
3.1.1. Flow Configuration Gas
Measurement region
U
V
X
Y
b2
b1
a
Ø51
Fi
4 S h
ti di
f th
i
t b b
k
Gas
Measurement region
U
V
X
Y
b2
b1
a
Ø51
Figure 4. Schematic diagram of the economizer tube bank. Figure 4. Schematic diagram of the economizer tube bank. b2
b1
Figure 4. Schematic diagram of the economizer tube bank. Figure 4. Schematic diagram of the economizer tube bank. 5 of 16
5 of 17 Catalysts 2018, 8, 432
Catalysts 2018, 8, x FO
y
, , Table 1. Structural parameters of the economizer tube [25]. Di
t
/
Transversal
Longitudinal
Diameter/mm
Transversal
h
/
Longitudinal
h b / Material
Rows
Diameter/mm
Transversal
Pitch a/mm
Longitudinal
Pitch b1/mm
Longitudinal
Pitch b2/mm
SA 210 GrA1(N)
135
Φ51×6
144
102
69
Material
Rows
Diameter/mm
Pitch a/mm
Pitch b1/mm
Pitch b2/mm
SA 210
GrA1(N)
135
Φ51×6
144
102
69
Pitch a/mm
Pitch b1/mm
Pitch b2/mm
SA 210
GrA1(N)
135
Φ51×6
144
102
69 The velocity is selected at 8.12 m/s, which represents 100% of the boiler THA (turbine heat
acceptance) load. The diameters of the particles are selected at 50 µm, 100 µm, and 250 µm, with the
same mass flow. The mass flow of ash is set to 1.52 × 10−2 kg/s, equal to 32 g/m3 of the gas. The velocity is selected at 8.12 m/s, which represents 100% of the boiler THA (turbine heat
acceptance) load. The diameters of the particles are selected at 50 μm, 100 μm, and 250 μm, with the
same mass flow. The mass flow of ash is set to 1.52 × 10−2 kg/s, equal to 32 g/m3 of the gas. y
/ ,
p
(
acceptance) load. The diameters of the particles are selected at 50 μm, 100 μm, and 250 μm, with the
same mass flow. The mass flow of ash is set to 1.52 × 10−2 kg/s, equal to 32 g/m3 of the gas. Periodic_1
Periodic_2
Wall
Inlet
Outlet
X
Y
Z
Figure 5. Three-dimensional diagram of the economizer unit. Figure 5. Three-dimensional diagram of the economizer unit. Periodic_1
Periodic_2
Wall
Inlet
Outlet
X
Y
Z
Figure 5. Three-dimensional diagram of the economizer unit. Figure 5 Three-dimensional diagram of the economizer unit
Figure 5. Three-dimensional diagram of the economizer unit. Figure 5. Three-dimensional diagram of the economizer unit. 3 1 1 Flow Configuration
3.1.1. Flow Configuration
3.1.1. Flow Configuration Considering the effect of the boundary layer on the flow computation, the grid of the tube wall
is refined in Figure 6 (enlarged from the red frame of Figure 5). Then it will capture the internal flow
field information on the boundary layer. Moreover, the grid-independency study gives the
appropriate grid number, whose mean error is controlled at less than 2%. The grid number ensures
the accuracy and rapidity of the calculation
Considering the effect of the boundary layer on the flow computation, the grid of the tube wall is
refined in Figure 6 (enlarged from the red frame of Figure 5). Then it will capture the internal flow
field information on the boundary layer. Moreover, the grid-independency study gives the appropriate
grid number, whose mean error is controlled at less than 2%. The grid number ensures the accuracy
and rapidity of the calculation. Considering the effect of the boundary layer on the flow computation, the grid of the tube wall
is refined in Figure 6 (enlarged from the red frame of Figure 5). Then it will capture the internal flow
field information on the boundary layer. Moreover, the grid-independency study gives the
appropriate grid number, whose mean error is controlled at less than 2%. The grid number ensures
the accuracy and rapidity of the calculation. Figure 6. Grid refinement of the tube wall. Figure 6. Grid refinement of the tube wall. Figure 6. Grid refinement of the tube wall. Figure 6. Grid refinement of the tube wall. Figure 6. Grid refinement of the tube wall. Figure 6. Grid refinement of the tube wall. 3 1 2 Governing Equations
3.1.2. Governing Equations
3.1.2. Governing Equations Gas Motion Model
Gas Motion Model
Gas Motion Model The total energy is calculated as: e = CpT + 1
2V2
f
(6) (6) The standard k-ε turbulence model is as follows [28]: The standard k-ε turbulence model is as follows [28]: The standard k-ε turbulence model is as follows [28]: ∂(ρk f ui)
∂xi
=
∂
∂xj
µ + µt
σk
∂k
∂xj
+ Gk + Gb −ρε
−YM + Sk
(7)
∂(ρεui)
∂xi
=
∂
∂xj
µ + µt
σε
∂ε
∂xj
+C1ε ε
k f (Gk + C3εGb) −C2ερ ε2
k + Sε
(8)
where:
µt = ρCµ
k2
f
ε
(9) ∂(ρk f ui)
∂xi
=
∂
∂xj
µ + µt
σk
∂k
∂xj
+ Gk + Gb −ρε
−YM + Sk
(7)
∂(ρεui)
∂xi
=
∂
∂xj
µ + µt
σε
∂ε
∂xj
+C1ε ε
k f (Gk + C3εGb) −C2ερ ε2
k + Sε
(8) ∂(ρk f ui)
∂xi
=
∂
∂xj
µ + µt
σk
∂k
∂xj
+ Gk + Gb −ρε
−YM + Sk
(7) (7) ∂(ρεui)
∂xi
=
∂
∂xj
µ + µt
σε
∂ε
∂xj
C
ε (G
C G )
C
ε2
S
(8) =
∂
∂xj
µ + µt
σε
∂ε
∂xj
+C1ε ε
k f (Gk + C3εGb) −C2ερ ε2
k + Sε
(8) (8) +C1ε ε
k f (Gk + C3εGb) −C2ερ ε2
k + Sε
(8) where: µt = ρCµ
k2
f
ε
(9) (9) gian Formulation for Particle Motion Model Lagrangian Formulation for Particle Motion Model Gas Motion Model
Gas Motion Model
Gas Motion Model Gas Motion Model
Gas from the furnace flows around the tube bank of the economizer. The flow field changes, but
it meets Navier–Stokes equations. Considering the flow as a turbulent flow, the two-equation
turbulent model (standard k-ε model) is introduced. The Navier–Stokes equations coupled with the
standard k-ε turbulence model is employed to solve the gas motion. Navier–Stokes equations of gas
f ll
Gas from the furnace flows around the tube bank of the economizer. The flow field changes, but
it meets Navier–Stokes equations. Considering the flow as a turbulent flow, the two-equation
turbulent model (standard k-ε model) is introduced. The Navier–Stokes equations coupled with the
standard k-ε turbulence model is employed to solve the gas motion. Navier–Stokes equations of gas
are as follows [26 27]:
Gas from the furnace flows around the tube bank of the economizer. The flow field changes,
but it meets Navier–Stokes equations. Considering the flow as a turbulent flow, the two-equation
turbulent model (standard k-ε model) is introduced. The Navier–Stokes equations coupled with the
standard k-ε turbulence model is employed to solve the gas motion. Navier–Stokes equations of gas are
as follows [26,27]:
∂(
) ∂(ρ f ui)
∂xi
= 0
(2) ∂(ρ f ui)
∂xi
= 0 (2) 6 of 16 Catalysts 2018, 8, 432 6 of 16 ∂(ρ f uiuj)
∂xj
= ρ f g −∂p
∂xi
+ ∂τij
∂xj
(3) ∂(ρ f uiuj)
∂xj
= ρ f g −∂p
∂xi
+ ∂τij
∂xj
(3)
∂
ρ f eui
∂xi
= −∂(uip)
∂xi
+ ∂
∂xi
k ∂T
∂xi
+ ∂
uτij
∂xi
(4) (3) ∂
ρ f eui
∂xi
= −∂(uip)
∂xi
+ ∂
∂xi
k ∂T
∂xi
+ ∂
uτij
∂xi
(4) (4) τij is the stress tensor, excluding the surface pressure. The stress tensor is calculated as:
! τij = µ
∂ui
∂xj
+ ∂uj
∂xi
! −2
3µ∂uk
∂xk
δij
(5) (5) e is the total energy, consisting of the internal and kinetic energy. The total energy is calculated as: e is the total energy, consisting of the internal and kinetic energy. Lagrangian Formulation for Particle Motion Model The particle motion is traced by Newton’s Second Law in Formula (10), driven by the drag force
FD, thermophoretic force FT, gravity FG, and Saffman lift force FSL [29]. dup
dt = FD + FT + FG + FSL
(10)
where,
FD = 18µ
ρpd2p
CDRe
24
u f −up
(11)
FT = −
6πdpµ2CS
k f /kp + CtKn
ρ(1 + 3CmKn)
1 + 2k f /kp + 2CtKn
1
mpT ∇T
(12)
FG =
g
ρp −ρ f
ρp
(13)
FSL =
2Kv1/2ρdij
ρpdp(dlkdkl)1/4
u f −up
(14) dup
dt = FD + FT + FG + FSL
(10)
where,
FD = 18µ
ρpd2p
CDRe
24
u f −up
(11)
FT = −
6πdpµ2CS
k f /kp + CtKn
ρ(1 + 3CmKn)
1 + 2k f /kp + 2CtKn
1
mpT ∇T
(12)
dup
dt = FD + FT + FG + FSL
(10) dup
dt = FD + FT + FG + FSL
(10)
where,
FD = 18µ
ρpd2p
CDRe
24
u f −up
(11) (10) where, FD = 18µ
ρpd2p
CDRe
24
u f −up
(11) (11) FT = −
6πdpµ2CS
k f /kp + CtKn
ρ(1 + 3CmKn)
1 + 2k f /kp + 2CtKn
1
mpT ∇T
(12) FT = −
6πdpµ2CS
k f /kp + CtKn
ρ(1 + 3CmKn)
1 + 2k f /kp + 2CtKn
1
mpT ∇T
(12)
FG =
g
ρp −ρ f
ρp
(13)
FSL =
2Kv1/2ρdij
ρpdp(dlkdkl)1/4
u f −up
(14) (12) (13) FSL =
2Kv1/2ρdij
ρpdp(dlkdkl)1/4
u f −up
(14) (14) Particle-Wall Collision Model Particle-Wall Collision Model In particle motion, the particle–particle collision and the particle-wall collision change the motion
state, including velocity and direction of motion. In consideration of the economizer bank in the
tail shaft flue and low concentration of ash, there are relatively few possibilities of particle–particle Catalysts 2018, 8, 432 7 of 16 collision. This research mainly focuses on the particle-wall collision, neglecting the particle–particle
collisions. Therefore, this study adopted the DPM approach instead of the DEM (discrete element
method) approach. In the particle-wall collision, the normal and tangential components of reflected
velocity are achieved by the coefficient of velocity restitution. Lagrangian Formulation for Particle Motion Model The coefficient of velocity restitution is
caused by kinetic energy loss, a function of the incidence angle α in the particle-wall collision model,
as follows [30]: en = 0.993 −1.76α + 1.56α2 −0.49α3
(15)
et = 0.998 −1.66α + 2.11α2 −0.76α3
(16) (15) (15)
(16) (16) Erosion Model Particle-wall collision not only changes the motion state, but also removes the material. Huang’s
erosion model was adopted to estimate the abrasion loss from the following Formula (17). Huang’s
erosion model includes mechanisms of deformation damage removal and cutting removal [10]. This model also demonstrates the effect of particle size on erosion. The erosion rate Er is the ratio of
abrasion loss and particle mass. Er = Cρ0.15
p
Vp sin α
2.3 + Dm0.1875
p
d−0.0625
p
V2.375
p
(cos α)2(sin α)0.375
(17) (17) Numerical Procedures The spatial discretization applies the second-order upwind scheme to discretize the whole
convective terms. In addition, the numerical calculation adopts the Eulerian–Lagrangian frame, and the
SIMPLEC algorithm (a semi-implicit algorithm) is applied to pressure/velocity coupling in the Eulerian
frame. This paper is divided into two numerical procedures, as follows: 1. Step 1: Verification of erosion model on SA210 GrA1(N); 2. Step 2: Erosion calculation of economizer unit. 4 Re ult a d Di
u
io
4. Results and Discussion 4 1 E
i
L
4.1. Erosion Loss 4.1.1. Global Erosion Loss 3.2. Verification of Erosion Model 3.2. Verification of Erosion Model C and D are related to the properties of the particle and economizer material in Formula (17). C and D are determined by fitting the curve. By comparing with the erosion experimental data by
the ASTM standard-tested bed in the India National Institute of Technology [31,32], the accuracy of
Huang’s erosion model was verified and found to be appropriate for SA 210GrA1(N) in Figures 7
and 8. Figure 7 gives the relation between the incidence angle and the erosion rate Er. Compared to
Finnie’s erosion model, Huang’s erosion model can not only estimate the effect of the small impact
angle, but also the large angle. Figure 8 shows the relation between the particle diameter dp and
the erosion rate Er. From Figures 7 and 8, the predicted results obtained are consistent and in good
agreement with experimental results reported elsewhere. For the erosion curve of the impact angle or
the ash size, the mean relative error is less than 5%, which satisfies the research requirements. Catalysts 2018, 8, x FOR PEER REVIEW
8 of 1
Finnie’s erosion model, Huang’s erosion model can not only estimate the effect of the small impac
angle, but also the large angle. Figure 8 shows the relation between the particle diameter
p
d and
the erosion rate
r
E . From Figures 7 and 8, the predicted results obtained are consistent and in good
agreement with experimental results reported elsewhere. For the erosion curve of the impact angle
or the ash size, the mean relative error is less than 5%, which satisfies the research requirements. Figure 7. Erosion curve of impact angle on SA 210GrA1. 0
20
40
60
80
100
0.000
0.001
0.002
0.003
0.004
0.005
0.006
0.007
Er/(g⋅kg
-1)
a/°
Experiment
Finnie
Huang
Figure 7. Erosion curve of impact angle on SA 210GrA1. Figure 7. Erosion curve of impact angle on SA 210GrA
Figure 7. Erosion curve of impact angle on SA 210GrA1. 8 of 16 Catalysts 2018, 8, 432 Figure 8. Erosion curve of ash size on SA 210GrA1. 40
80
120
160
200
240
280
0.005
0.006
0.007
0.008
0.009
0.010
0.011
0.012
Er/(g⋅kg
-1)
dp/µm
Experiment
Huang
Figure 8. Erosion curve of ash size on SA 210GrA1. 40
80
120
160
200
240
280
0.005
0.006
0.007
0.008
0.009
0.010
0.011
0.012
Er/(g⋅kg
-1)
dp/µm
Experiment
Huang Figure 8. 4.1.1. Global Erosion Loss 4.1.1. Global Erosion Loss
Figure 9 shows the global erosion loss under different ash sizes. From Figure 9, the globa
erosion loss is linearly related to the working time. Meanwhile, as the ash size increases, the growth
amplification of global erosion loss decreases (
2
1
∆
∆>
). This coincides with the fact that it is hard to
change the motion of the larger particle, which has the larger inertia. In other words, the motion o
the larger particle becomes smaller, and the collision point of a single particle from the injection
changes little. Thus, the mass flow of ash impacting the economizer increases slowly and become
stable gradually, which contributes to the slow growth amplification. In addition, the particle
Figure 9 shows the global erosion loss under different ash sizes. From Figure 9, the global
erosion loss is linearly related to the working time. Meanwhile, as the ash size increases, the growth
amplification of global erosion loss decreases (∆1 > ∆2). This coincides with the fact that it is hard
to change the motion of the larger particle, which has the larger inertia. In other words, the motion
of the larger particle becomes smaller, and the collision point of a single particle from the injection
changes little. Thus, the mass flow of ash impacting the economizer increases slowly and becomes
stable gradually, which contributes to the slow growth amplification. In addition, the particle rebound
or collision also impacts the global erosion loss, illustrated in Section 4.1.2. Catalysts 2018, 8, x FOR PEER REVIEW
9 of 1 n also impacts the global erosion loss, illustrated in Sec
0
180
360
540
720
0
60
120
180
240
300
360
∆1
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm
∆2
Figure 9 Global erosion loss under different ash sizes
Figure 9. Global erosion loss under different ash sizes. t/d i
Gl b l
l
d
d ff
h
Figure 9. Global erosion loss under different ash sizes. 3.2. Verification of Erosion Model Erosion curve of ash size on SA 210GrA
Figure 8. Erosion curve of ash size on SA 210GrA1. 4.1.2. Local Erosion Loss 4.1.2. Local Erosion Loss 4.1.2. Local Erosion Loss
Figure 10 shows the local erosion loss of different rows under various ash sizes. From thi
figure, the local erosion loss is consistent with the global erosion loss. The local erosion loss i
approximately linear to the working time. The erosion loss of the first row occupies more than half o
the global erosion loss. Ash impacts the first rows, and the kinetic energy decreases. Then most o
Figure 10 shows the local erosion loss of different rows under various ash sizes. From this figure,
the local erosion loss is consistent with the global erosion loss. The local erosion loss is approximately
linear to the working time. The erosion loss of the first row occupies more than half of the global
erosion loss. Ash impacts the first rows, and the kinetic energy decreases. Then most of the ash
particles follow the gas flow, which hinders the particle collision in the other rows. g
p
gy
the ash particles follow the gas flow, which hinders the particle collision in the other rows. Similarly, as the ash size increases, the growth amplification of local erosion loss decreases in
the first row. Meanwhile, with the ash size increased, the mass flow of ash impacting the economize
rises in the first row, which raises the probability of particle rebound and collision in other row
(compared with Figure 10a–h). For an ash particle diameter of 200 µm, these rebound phenomen
occur in all rows. Second place is 150 µm, and 100 µm is the least. The probability of the particl
Similarly, as the ash size increases, the growth amplification of local erosion loss decreases in the
first row. Meanwhile, with the ash size increased, the mass flow of ash impacting the economizer rises
in the first row, which raises the probability of particle rebound and collision in other rows (compared
with Figure 10a–h). For an ash particle diameter of 200 µm, these rebound phenomena occur in all rows. Second place is 150 µm, and 100 µm is the least. The probability of the particle rebound ultimately
influences the growth amplification of global erosion. As the ash size increases to a certain numerical 9 of 16
na
cle Catalysts 2018, 8, 432
(compared w
occur in all r value, the probability of the particle rebound reaches the limit, which leads the growth amplification
to decrease. 4.1.2. Local Erosion Loss y
g
p
g
to a certain numerical value, the probability of the particle rebound reaches the limit, which leads the
growth amplification to decrease. he probability of the particle rebound reaches the limit, which leads the growth amp
ase. p
y
p
owth amplification to decrease. 0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg
t/d
dp=100µm
dp=150µm
dp=200µm
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm
(a) First row
(b) Second row
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm
(c) Third row
(d) Fourth row
atalysts 2018, 8, x FOR PEER REVIEW
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm
(e) Fifth row
(f) Sixth row
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm
(g) Seventh row
(h) Eighth row
Figure 10. Local erosion loss under different ash sizes. Figure 10. Local erosion loss under different ash sizes. 4.1.2. Local Erosion Loss 0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm 0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg
t/d
dp=100µm
dp=150µm
dp=200µm (a) First row
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm
s 2018, 8, x FOR PEER REVIEW (b) Second row
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm (b) Second row (b) Second row ) First row (c) Third row
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm (d) Fourth row
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm d) Fourth row (c) Third row (f) Sixth row
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm (e) Fifth row
0
180
360
540
720
0
40
80
120
160
200
δm×10
3/kg⋅m
-1
t/d
dp=100µm
dp=150µm
dp=200µm (e) Fifth row (f) Sixth row (g) Seventh row (g) Seventh row (h) Eighth row Figure 10. Local erosion loss under different ash sizes. Figure 10. Local erosion loss under different ash sizes. Catalysts 2018, 8, 432 10 of 16 10 of 16 4.2. Evolution Process of Erosion 4.2. Evolution Process of Erosion 4.2.1. Maximum Erosion Depth 4.2.1. Maximum Erosion Depth Figure 11 shows the maximum erosion depths of the different rows under various ash sizes. The
maximum erosion depth is defined as the most critical region, as it represents the thinnest location of
the tube wall. From this figure, the maximum erosion depth depends linearly on the working time at
the initial time. However, compared to the linear trend (gray dashed line in Figure 11a,b), the growth
of the maximum erosion depth slows down gradually. This growing trend forms a favorable flow
passage, which prolongs the service life of the economizer effectively. Since maximum erosion depth in the first row is maximal, this row is the most dangerous and of
the greatest concern. Maximum erosion depth of the first row is double or even several times that of
other rows. Moreover, not in all rows, the 200 µm ash particle impacts the most powerfully, and the
maximum erosion depth is maximal. In the third, fourth, fifth, and eighth row, the maximum is under
an ash particle diameter of 150 µm. In the sixth row, the maximum appears under an ash particle
diameter of 100 µm. This is mainly caused by particle rebound in the first row, which drives other
rows to remove more material as the rebounded particles impact them with different kinetic energies
and incidence angles. Catalysts 2018, 8, x FOR PEER REVIEW
11 of 17 0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
linearity
safe region
0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
linearity
(a) First row
(b) Second row
0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
(c) Third row
(d) Fourth row
3 5
d
100
3 5
Figure 11. Cont. 4.2.1. Maximum Erosion Depth 0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
linearity
safe region 0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
linearity (b) Second row
0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm (a) First row
0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm b) Second row (a) First row Figure 11. Cont. 11 of 16 Catalysts 2018, 8, 432 0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
(e) Fifth row
(f) Sixth row
Catalysts 2018, 8, x FOR PEER REVIEW
12 o
0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
(g) Seventh row
(h) Eighth row
Figure 11. Maximum erosion depth under different ash sizes. Figure 11. Maximum erosion depth under different ash sizes. 0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
Catalysts 2018, 8, x FOR PEER REVIEW 0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm
12 (f) Sixth row
0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm (e) Fifth row
0
180
360
540
720
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
h×10
3/m
t/d
dp=100µm
dp=150µm
dp=200µm (h) Eighth row Figure 11. Maximum erosion depth under different ash size
Figure 11. Maximum erosion depth under different ash sizes. 4.2.2. Erosion Profil
4.2.2. Erosion Profile 4.2.2. Erosion Profil
4.2.2. Erosion Profile Considering that erosion in the first row is the most serious, this paper focuses on the evolution
process of the erosion profile for the first row. Figure 12 shows the evolution process of the erosio
profile with different ash sizes in the first row. From this figure, as time proceeds, a “V-shape” i
gradually formed, which is similar to the erosion profile in Figure 1. This confirms that the dynami
mesh technology is advisable to describe the erosion of economizer tubes. Considering that erosion in the first row is the most serious, this paper focuses on the evolution
process of the erosion profile for the first row. Figure 12 shows the evolution process of the erosion
profile with different ash sizes in the first row. From this figure, as time proceeds, a “V-shape” is
gradually formed, which is similar to the erosion profile in Figure 1. This confirms that the dynamic
mesh technology is advisable to describe the erosion of economizer tubes. mesh technology is advisable to describe the erosion of economizer tubes. In addition, θ is introduced as the angle between the position of the erosion profile and th
reverse direction of incoming flow, and θmax represents θ in the location of maximum erosion dept
in Figure 12a. From Figure 12, larger ash impacts the first row with a smaller angle of θmax. A
mentioned earlier, larger ash has greater inertia and less motion, ensuring that the location of th
maximum erosion rate appears with a smaller θ. In addition, θ is introduced as the angle between the position of the erosion profile and the
reverse direction of incoming flow, and θmax represents θ in the location of maximum erosion depth in
Figure 12a. From Figure 12, larger ash impacts the first row with a smaller angle of θmax. As mentioned
earlier, larger ash has greater inertia and less motion, ensuring that the location of the maximum
erosion rate appears with a smaller θ. 12 of 16
on of the Catalysts 2018, 8, 432
mentioned earlie
i
i Catalysts 2018, 8, 432
12 of 16
mentioned earlier, larger ash has greater inertia and less motion, ensuring that the location of the
maximum erosion rate appears with a smaller θ. 4.2.2. Erosion Profil
4.2.2. Erosion Profile d
360
=
t
d
540
=
t
(a)
m
100µ
=
p
d d
540
=
t h /m
0.0000
0.0005
0.0010
0.0015
0.0020
0.0025
0.0030
d
720
=
t
d
720
=
t θmax
max
depth
d
180
=
t d
720
=
t d
540
=
t d
360
=
t d
180
=
t (a)
m
100µ
=
p
d d
540
=
t d
360
=
t
x FOR PEER REVIEW d
180
=
t
Catalysts 2018, 8, d
180
=
t
Catalysts 2 d
180
=
t
Catalysts 2 d
720
=
t d
540
=
t d
360
=
t
R PEER REVIE (b)
m
150µ
=
p
d (b)
m
150µ
=
p
d
d
360
=
t
d
540
=
t
(c)
m
200µ
=
p
d m
0µ
d
540
=
t
m
200µ
= d
720
=
t d
180
=
t d
720
=
t d
540
=
t (c)
m
200µ
=
p
d Figure 12. Evolution process of erosion profile in the fir
Figure 12. Evolution process of erosion profile in the first row. 4.2.2. Erosion Profil
4.2.2. Erosion Profile θmax
max
depth
h /m
0.0000
0.0005
0.0010
0.0015
0.0020
0.0025
0.0030
d
180
=
t
d
360
=
t
d
540
=
t
d
720
=
t
(a)
m
100µ
=
p
d
d
180
=
t
d
360
=
t
d
540
=
t
d
720
=
t
(b)
m
150µ
=
p
d
Catalysts 2018, 8, x FOR PEER REVIEW
13 o
d
180
=
t
d
360
=
t
d
540
=
t
d
720
=
t
(c)
m
200µ
=
p
d
Figure 12. Evolution process of erosion profile in the first row. Figure 12. Evolution process of erosion profile in the first row. 4 3 E
l ti
P
f P
ti l M ti maximum erosion rate appears with a smaller θ. θmax
max
depth
h /m
0.0000
0.0005
0.0010
0.0015
0.0020
0.0025
0.0030
d
180
=
t
d
360
=
t
d
540
=
t
d
720
=
t
(a)
m
100µ
=
p
d
d
180
=
t
d
360
=
t
d
540
=
t
d
720
=
t
(b)
m
150µ
=
p
d
Catalysts 2018, 8, x FOR PEER REVIEW
d
180
=
t
d
360
=
t
d
540
=
t
d
720
=
t
(c)
m
200µ
=
p
d
Figure 12. Evolution process of erosion profile in the first row. Figure 12. Evolution process of erosion profile in the first row. rate appears with a smaller θ. 4.3. Evolution Process of Particle M
4.3. Evolution Process of Particle Motion 4.3. Evolution Process of Particle M
4.3. Evolution Process of Particle Motion f
Figure 13 shows the particle motion from the specific position in the inlet. From this figu
particle collision point obviously moves to the center of the economizer tube over time. Mean
due to more material loss with a larger particle, the larger particle moves across a longer distan
order to describe the particle motion along the radial and tangential direction, Figure 14 is ad
to illustrate the collision point trajectory from the specific position in the inlet, which is the top
of Figure 13a. From this figure, with time increasing, the collision point trajectory moves alon
increasing direction of the absolute value of θ. Just because of this, the probabilities of imping
and the growth of the maximum erosion depth slow down gradually in later stages. Althou
trend of erosion loss is unlike the maximum erosion depth after 2 years, the erosion loss bas
this result is predicted to slowly increase in the future
Figure 13 shows the particle motion from the specific position in the inlet. From this figure, the
particle collision point obviously moves to the center of the economizer tube over time. Meanwhile,
due to more material loss with a larger particle, the larger particle moves across a longer distance. In
order to describe the particle motion along the radial and tangential direction, Figure 14 is adopted
to illustrate the collision point trajectory from the specific position in the inlet, which is the top view
of Figure 13a. From this figure, with time increasing, the collision point trajectory moves along the
increasing direction of the absolute value of θ. Just because of this, the probabilities of impingement
and the growth of the maximum erosion depth slow down gradually in later stages. Although the
trend of erosion loss is unlike the maximum erosion depth after 2 years, the erosion loss based on this
result is predicted to slowly increase in the future. 13 of 16
14 of 18 Catalysts 2018, 8, 432
Catalysts 2018, 8, x FOR , ,
O
EE
E IE
(c)
m
200μ
=
p
d
Figure 13. Particle motion. (c)
m
200μ
=
p
d
Figure 13. Particle motion. (c)
m
200μ
=
p
d Figure 13. Particle motion. Figure 13. Particle motion. 14 of 16 Catalysts 2018, 8, 432 Figure 13. Particle motion. 4.3. Evolution Process of Particle M
4.3. Evolution Process of Particle Motion radial direction
θ（+）
collision point
trajectory
0
180 360 540
720
t/d
Fi
14 C lli i
i t t
j
t
(
100
d
)
Figure 14. Collision point trajectory (dp = 100 µm). collision point
trajectory 0
180 360 540
t/d Figure 14. Collision point trajectory (dp = 100 µm). 4.4. Expiry Periods 4.4. Expiry Periods
In Figure 11a, the safe region is defined as the value below 1.99 mm (equal to the critical value
of 4.01 mm in wall thickness [25], which is the minimum wall thickness by the specific theoretical
calculation). When the maximum erosion depth is up to 1.99 mm, the first row of the economizer
tube easily bursts. From this figure, the expiry periods are respectively 710, 530, and 440 days with
100 µm 150 µm and 200 µm These data indicate the expiry period is shortened as the ash diameter
In Figure 11a, the safe region is defined as the value below 1.99 mm (equal to the critical value
of 4.01 mm in wall thickness [25], which is the minimum wall thickness by the specific theoretical
calculation). When the maximum erosion depth is up to 1.99 mm, the first row of the economizer tube
easily bursts. From this figure, the expiry periods are respectively 710, 530, and 440 days with 100 µm,
150 µm, and 200 µm. These data indicate the expiry period is shortened as the ash diameter increases. Moreover, as the ash size increases, the declining amplification of expiry periods is retarded. increases. Mor
t
d d
5. Conclusions retarded. 5. Conclusions
The present research aims to investigate a novel method for the solution of the evolution
process and its applications to the expiry period of an economizer bank The CFD DPM approach
The present research aims to investigate a novel method for the solution of the evolution process
and its applications to the expiry period of an economizer bank. The CFD-DPM approach coupled
with the UDF of the erosion model and the dynamic mesh technology is utilized to solve this complex
issue. Based on the results of the applications, the following conclusions are made: process and its applications to the expiry period of an economizer bank. The CFD DPM approach
coupled with the UDF of the erosion model and the dynamic mesh technology is utilized to solve
this complex issue. Based on the results of the applications, the following conclusions are made:
(1) The CFD-DPM approach coupled with the UDF of Huang’s erosion model and the dynamic
h t
h
l
d
ib
th
l ti
f
i
i
b
k
(1)
The CFD-DPM approach coupled with the UDF of Huang’s erosion model and the dynamic
mesh technology can describe the evolution process of erosion on an economizer bank, especially
the erosion profile; by comparing the simulation results with the erosion profile on-site, the
correctness is verified for this proposed CFD-DPM approach. mesh technology can describe the evolution process of erosion on an economizer bank,
especially the erosion profile; by comparing the simulation results with the erosion profile
on-site, the correctness is verified for this proposed CFD-DPM approach. (2)
The global/local erosion loss and the maximum erosion depth are linearly related to the working
time, but the growth of the maximum erosion depth slows down gradually in the later stage; as
the ash size increases, the growth amplification of global erosion loss, local erosion in the first
row, and the maximum erosion depth decrease. (3)
With increasing time, the collision point trajectory moves along the increasing direction of the
absolute value of θ in the first row, which explains why the growth of the maximum erosion
depth slows down in later stages. (3)
With increasing time, the collision point trajectory moves along the increasing direction of the
absolute value of θ in the first row, which explains why the growth of the maximum erosion
depth slows down in later stages. Funding: This research was funded by the National Natural Science Fund Program of China, grant number No.
51706043, and the Jiangsu Natural Science Foundation, grant number No. BK20170679. Acknowledgments: Research was supported by Datang Nanjing Environmental Protection Technology Co., Ltd.
Without the support, this work would not have been possible. Author Contributions: F.S. and X.J. led the project and coordinated the study; Y.D., C.Y. and B.Z. conducted the
modelling analysis; Y.D. and Z.Q. conducted the numerical simulation. C.Y. participated in the data analysis. Y.D.
and C.Y. prepared, and Z.Q. edited the manuscripts; Y.D. coordinated the manuscript submission. All authors
read and approved the final manuscript. increases. Mor
t
d d
5. Conclusions 4)
The expiry period is shortened as the ash diameter increases; moreover, as the ash size increa
the declining amplification of expiry periods is retarded. Author Contributions: F.S. and X.J. led the project and coordinated the study; Y.D., C.Y. and B.Z. conducted the
modelling analysis; Y.D. and Z.Q. conducted the numerical simulation. C.Y. participated in the data analysis. Y.D. and C.Y. prepared, and Z.Q. edited the manuscripts; Y.D. coordinated the manuscript submission. All authors
read and approved the final manuscript. Funding: This research was funded by the National Natural Science Fund Program of China, grant number No. 51706043, and the Jiangsu Natural Science Foundation, grant number No. BK20170679. Acknowledgments: Research was supported by Datang Nanjing Environmental Protection Technology Co., Ltd. Without the support, this work would not have been possible. 15 of 16 Catalysts 2018, 8, 432 Catalysts 2018, 8, 432 Conflicts of Interest: The authors declare no conflict of interest. 8.
Bitter, J. A study of erosion phenomena Part I. Wear 1963, 6, 5–21. [CrossRef] 7.
Finnie, I. Some reflections on the past and future of erosion. Wear 1995, 186–187, 1–10. [CrossRef] 6.
Finnie, I. Erosion of surfaces. Wear 1960, 3, 87–103. [CrossRef] .
Arabnejad, H.; Mansouri, A.; Shirazi, S.A.; McLaury, B.S. Abrasion erosion modeling in particulate fl
Wear 2017, 376–377, 1194–1199. [CrossRef] 6.
Finnie, I. Erosion of surfaces. Wear 1960, 3, 87–103. [CrossRef] increases. Mor
t
d d
5. Conclusions Nomenclature
Ai
area of grid element [m2]
K
model constant
C
model constant
k f
fluid thermal conductivity [W/(m·K)]
C1ε
model constant
Kn
Knudsen number
C2ε
model constant
mp
particle mass [kg]
C3ε
model constant
p
gas pressure [pa]
CD
drag coefficient
Re
Reynolds number
Cm
model constant
Sk
turbulence kinetic energy source term
[kg/(m·s3)]
Cp
specific heat [J/(kg·K)]
Sε
turbulence dissipation rate source term
[kg/(m·s4)]
CS
model constant
T
gas temperature [K]
Ct
model constant
u f
gas velocity vector [m/s]
Cµ
model constant
ui
gas velocity of i-direction [m/s]
dij
deformation tensor
up
particle velocity vector [m/s]
dp
particle diameter [m]
xi
the coordinate of i-direction [m]
D
model constant
Vp
particle velocity magnitude [m/s]
e
total energy [J/kg]
Vf
gas velocity magnitude [m/s]
en
normal coefficient of velocity restitution
YM
contribution of the fluctuating dilatation in
compressible turbulence to the overall
dissipation rate [kg/(m·s3)]
et
tangential coefficient of velocity restitution
α
incidence angle
Er
ratio of abrasion loss and particle mass
[g/kg]
ρ f
gas density [kg/m3]
FD
drag force [N]
ρm
density of economizer material [kg/m3]
FG
gravity [N]
ρp
particle density [kg/m3]
FT
thermophoretic force [N]
τij
Gas stress tensor [pa]
FSL
Saffman lift force [N]
δij
Kronecker tensor
g
acceleration of gravity [m/s2]
δm
erosion loss [kg/m]
Gb
generation of turbulence kinetic energy due
to buoyancy [kg/(m·s3)]
∆t
time interval [s]
Gk
generation of turbulence kinetic energy due
to the velocity gradients [kg/(m·s3)]
µ
gas viscosity [pa·s]
h
erosion depth [mm]
µt
gas second viscosity [pa·s]
hi,j
erosion depth of grid element [mm]
σk
turbulent Prandtl number for k
kp
particle thermal conductivity [W/(m·K)]
σε
turbulent Prandtl number for ε References Comparison of computed and m
particle velocities and erosion in water and air flows. Wear 2007, 263, 330–338. [CrossRef] 18. Shamshirband, S.; Malvandi, A.; Karimipour, A.; Goodarzi, M.; Afrand, M.; Petkovi´c, D.; Dahari, M.;
Mahmoodian, N. Performance investigation of micro- and nano-sized particle erosion in a 90◦elbow using
an ANFIS model. Powder Technol. 2015, 284, 336–343. [CrossRef] 19. Moakhar, R.S.; Mehdipour, M.; Ghorbani, M.; Mohebali, M.; Koohbor, B. Investigations of the failure in
boilers economizer tubes used in power plants. J. Mater. Eng. Perform. 2013, 22, 2691–2697. [CrossRef] 20. Ding, Q.; Tang, X.F.; Yang, Z.G. Failure analysis on abnormal corrosion of economizer tubes in a waste heat
boiler. Eng. Fail. Anal. 2017, 73, 129–138. [CrossRef] 21. Yang, L. One-fluid formulation for fluid–structure interaction with free surface. Comput. Methods Appl. Mech. Eng. 2018, 332, 102–135. [CrossRef] 2. Joshson, A.A. Dynamic-mesh CFD and its application to flapping-wing micro-air vehicles. In Proceeding
the 25th Army Science Conference, Orlando, FL, USA, 27–30 November 2006; ANSI: Orlando, FL, USA, 2 22. Joshson, A.A. Dynamic-mesh CFD and its application to flapping-wing micro-air vehicles. In Proceedings of
the 25th Army Science Conference, Orlando, FL, USA, 27–30 November 2006; ANSI: Orlando, FL, USA, 2006. 23. Savidis, S.A.; Aubram, D.; Rackwitz, F. Arbitrary Lagrangian-eulerian finite element formulation for
geotechnical construction processes. J. Theor. Appl. Mech. 2008, 38, 165–194. 3. Savidis, S.A.; Aubram, D.; Rackwitz, F. Arbitrary Lagrangian-eulerian finite element formulation
geotechnical construction processes. J. Theor. Appl. Mech. 2008, 38, 165–194. 24. Li, J.; Hesse, M.; Ziegler, J.; Woods, A.W. An arbitrary Lagrangian Eulerian method for moving-boundary
problems and its application to jumping over water. J. Comput. Phys. 2005, 208, 289–314. [CrossRef] 25. Yuping, C. Boiler Instruction Manual of DAIHAI in China; Shang Boiler Works, Ltd.: Shanghai, China, 2006. 26. Versteeg, H.; Malalasekera, W. An Introduction to Computational Fluid Dynamics: The Finite Volume Method;
Prentice Hall: London, UK, 1995. 27. Gao, W.; Li, Y.; Kong, L. Numerical investigation of erosion of tube sheet and tubes of a shell and tube heat
exchanger. Comput. Chem. Eng. 2017, 96, 115–127. [CrossRef] 28. Launder, B.E.; Spalding, D.B. The numerical computation of turbulent flows. Comput. Methods Appl. Mech. Eng. 1974, 3, 269–289. [CrossRef] 29. ANSYS. Ansys Fluent User’s Guide; Ansys Inc.: Canonsburg, PA, USA, 2015. 30. Grant, G.; Tabakoff, W. Erosion Prediction in Turbomachinery Resulting from environmental solid particles. J. Aircr. 1975, 12, 471–478. [CrossRef] 31. ASTM. References 1. Arabnejad, H.; Mansouri, A.; Shirazi, S.A.; McLaury, B.S. Abrasion erosion modeling in particulate flow. Wear 2017, 376–377, 1194–1199. [CrossRef] 2. Alam, T.; Farhat, Z.N. Slurry erosion surface damage under normal impact for pipeline steels. Eng. Fail. Anal. 2018, 90, 116–128. [CrossRef] 3. Eichner, D.; Schlieter, A.; Leyens, C.; Shang, L.; Shayestehaminzadeh, S.; Schneider, J.M. Solid particle erosion
behavior of nanolaminated Cr2AlC films. Wear 2018, 402–403, 187–195. [CrossRef] 4. Ji, X.; Wu, J.; Pi, J.; Cheng, J.; Shan, Y.; Zhang, Y. Slurry erosion induced surface nanocrystallization of bulk
metallic glass. Appl. Surf. Sci. 2018, 440, 1204–1210. [CrossRef] 5. William, L. Failure analysis on the economisers of a biomass fuel boiler. Eng. Fail. Anal. 2013, 31, 101–117. [CrossRef] Catalysts 2018, 8, 432 16 of 16 16 of 16 9. Bitter, J. A study of erosion phenomena Part II. Wear 1963, 6, 169–190. [CrossRef] 10. Huang, C.; Chiovelli, S.; Minev, P.; Luo, J.; Nandakumar, K. A comprehensive phenomenological model for
erosion of materials in jet flow. Powder Technol. 2008, 187, 273–279. [CrossRef] 1. Grant, G.; Tabakoff, W. An Experimental Investigation of the Erosion Characteristics of 2024 Aluminum A
Report; Cincinnati University: Cincinnati, OH, USA, 1973; p. 49. 12. Oka, Y.I.; Okamura, K.; Yoshida, T. Practical estimation of erosion damage caused by solid particle impact:
Part 1: Effects of impact parameters on a predictive equation. Wear 2005, 259, 95–101. [CrossRef] 13. Oka, Y.I.; Yoshida, T. Practical estimation of erosion damage caused by solid particle impact: Part 2:
Mechanical properties of materials directly associated with erosion damage. Wear 2005, 259, 102–109. [CrossRef] 14. Haugen, K.; Kvernvold, O.; Ronold, A.; Sandberg, R. Sand erosion of wear-resistant materials: Erosion in
choke valves. Wear 1995, 186–187, 179–188. [CrossRef] 15. Ahlert, K. Effects of Particle Impingement Angle and Surface Wetting on Solid Particle Erosion of AISI 1018
Steel. Master’s. Thesis, The University of Tulsa, Tulsa, OK, USA, 1994. 6. McLaury, B.S. Predicting Solid Particle Erosion Resulting from Turbulent Fluctuations in Oilfield Geomet
Ph.D. Thesis, The University of Tulsa, Tulsa, OK, USA, 1996. 16. McLaury, B.S. Predicting Solid Particle Erosion Resulting from Turbulent Fluctuations in Oilfield Geometries. Ph.D. Thesis, The University of Tulsa, Tulsa, OK, USA, 1996. 17
Zhang Y; Reuterfors E P; McLaury B S ; Shirazi S A ; Rybicki E F Comparison of computed and measured 17. Zhang, Y.; Reuterfors, E.P.; McLaury, B.S.; Shirazi, S.A.; Rybicki, E.F. © 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) license (http://creativecommons.org/licenses/by/4.0/). References Standard test method for conducting erosion tests by solid particle impingement. ASTM Int. 2013. [CrossRef] 32. Sagayaraj, T.A.D.; Suresh, S.; Chandrasekar, M. Experimental studies on the erosion rate of different heat
treated carbon steel economizer tubes of power boilers by fly ash particles. Int. J. Miner. Metall. Mater. 2009,
16, 534–539. [CrossRef] © 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) license (http://creativecommons.org/licenses/by/4.0/).
|
https://openalex.org/W2136342928
|
https://acp.copernicus.org/articles/11/12517/2011/acp-11-12517-2011.pdf
|
English
| null |
A Lagrangian view of convective sources for transport of air across the Tropical Tropopause Layer: distribution, times and the radiative influence of clouds
|
Atmospheric chemistry and physics
| 2,011
|
cc-by
| 17,531
|
A. Tzella1,* and B. Legras1
1Laboratoire de M´et´eorologie Dynamique, CNRS, UMR8539, Ecole Normale Sup´erieure, 24 rue Lhomond,
Paris, 75005, France
*now at: School of Mathematics, University of Edinburgh, Edinburgh EH9 3JZ, UK
Received: 14 June 2011 – Published in Atmos. Chem. Phys. Discuss.: 28 June 2011
Revised: 1 November 2011 – Accepted: 4 December 2011 – Published: 13 December 2011 A. Tzella1,* and B. Legras1
1Laboratoire de M´et´eorologie Dynamique, CNRS, UMR8539, Ecole Normale Sup´erieure, 24 rue Lhomond,
Paris, 75005, France
*now at: School of Mathematics, University of Edinburgh, Edinburgh EH9 3JZ, UK
Received: 14 June 2011 – Published in Atmos. Chem. Phys. Discuss.: 28 June 2011
Revised: 1 November 2011 – Accepted: 4 December 2011 – Published: 13 December 2011 Abstract. The tropical tropopause layer (TTL) is a key re-
gion controlling transport between the troposphere and the
stratosphere. The efficiency of transport across the TTL de-
pends on the continuous interaction between the large-scale
advection and the small-scale intermittent convection that
reaches the Level of Zero radiative Heating (LZH). The wide
range of scales involved presents a significant challenge to
determine the sources of convection and quantify transport
across the TTL. Here, we use a simple Lagrangian model,
termed TTL detrainment model, that combines a large en-
semble of 200-day back trajectory calculations with high-
resolution fields of brightness temperatures (provided by the
CLAUS dataset) in order to determine the ensemble of trajec-
tories that are detrained from convective sources. The trajec-
tories are calculated using the ECMWF ERA-Interim winds
and radiative heating rates, and in order to establish the ra-
diative influence of clouds, the latter rates are derived both
under all-sky and clear-sky conditions. ±1 km (∓5 K) in the altitude of cloud top heights (the main
sensitivity appearing in the times to escape the immediate
neighbourhood of the LZH) while some seasonal and re-
gional transport characteristics are apparent for times up to
60 days. The strong horizontal mixing that characterizes the
TTL ensures that most air of convective origin is well-mixed
within the tropical and eventually within the extra-tropical
lower-stratosphere. ±1 km (∓5 K) in the altitude of cloud top heights (the main
sensitivity appearing in the times to escape the immediate
neighbourhood of the LZH) while some seasonal and re-
gional transport characteristics are apparent for times up to
60 days. The strong horizontal mixing that characterizes the
TTL ensures that most air of convective origin is well-mixed
within the tropical and eventually within the extra-tropical
lower-stratosphere. Atmos. Chem. Phys., 11, 12517–12534, 2011
www.atmos-chem-phys.net/11/12517/2011/
doi:10.5194/acp-11-12517-2011
© Author(s) 2011. CC Attribution 3.0 License. Atmos. Chem. Phys., 11, 12517–12534, 2011
www.atmos-chem-phys.net/11/12517/2011/
doi:10.5194/acp-11-12517-2011
© Author(s) 2011. CC Attribution 3.0 License. Atmos. Chem. Phys., 11, 12517–12534, 2011
www.atmos-chem-phys.net/11/12517/2011/
doi:10.5194/acp-11-12517-2011
© Author(s) 2011. CC Attribution 3.0 License. 1
Introduction It is now widely accepted that most of the transport of tro-
pospheric air into the stratospheric “overworld” at poten-
tial temperatures above about 380 K takes place in the trop-
ics (see reviews by Holton et al., 1995; Stohl et al., 2003),
across what is now known as the Tropical Tropopause Layer
(TTL) (Highwood and Hoskins, 1998; Folkins et al., 1999;
Fueglistaler et al., 2009a). This layer, whose vertical extent
is over several kilometres, spans the gradual transition from
a region dominated by the convectively overturning motion
of the Hadley-Walker circulation to a region of slow ascent,
controlled by the tropical branch of the Brewer-Dobson cir-
culation. The efficiency at which air is transported across
the TTL depends on both the large-scale advection and the
local sources of deep convection. A detailed quantification
of their combined effect is challenging because of the large
range of scales involved. Such a quantification is particu-
larly important for halogenated Very Short-Lived Substances
(VSLS) whose impact on ozone depletion relies on their ef-
ficient transport into the stratosphere (see e.g. WMO, 2007). We show that most trajectories are detrained near the mean
LZH with the horizontal distributions of convective sources
being highly-localized, even within the space defined by deep
convection. As well as modifying the degree of source lo-
calization, the radiative heating from clouds facilitates the
rapid upwelling of air across the TTL. However, large-scale
motion near the fluctuating LZH can lead a significant pro-
portion of trajectories to alternating clear-sky and cloudy re-
gions, thus generating a large dispersion in the vertical trans-
port times. The distributions of vertical transport times are
wide and skewed and are largely insensitive to a bias of about Correspondence to: A. Tzella
(a.tzella@ed.ac.uk) Published by Copernicus Publications on behalf of the European Geosciences Union. A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12518 distances (Holton and Gettelman, 2001; Fueglistaler et al.,
2004; Bonazzola and Haynes, 2004). Horizontal transport
could play a significant role in the vertical transport of cloud
air into the stratosphere. Because clouds are spatially lo-
calized and intermittent, both the heating rates and the A-
LZH are highly fluctuating in space and time. In contrast,
in clear-sky, the distributions of heating rates are, in general,
smoother. 1
Introduction Horizontal motion can thus transport cloud air that
is detrained within a certain region into other regions, with
very different vertical heating rate profiles. As a result, cloud
air detrained above the A-LZH may subside back into the tro-
posphere or remain for a long time near the A-LZH so that its
motion is fluctuating in the vertical direction. The combined
effect of the radiative heating associated with clouds and the
large-scale horizontal flow for transport of air of convective
origin into the stratosphere is a priori unknown. Air from the boundary layer is rapidly (within hours)
transported into the TTL by deep convection. The latter
frequently penetrates the region near the TTL base, com-
monly taken to lie above the level of maximum convective
outflow (between 345–355 K, 12–14 km; see e.g. Gettelman
and de Forster, 2002; Fueglistaler et al., 2009a). However,
most air detrained in this region descends back to the bound-
ary layer. With increasing altitude, convection becomes in-
creasingly rare (see e.g. Liu and Zipser, 2005; Fu et al., 2007)
while the decrease of temperature leads to a significant drop
in water vapour. As a result, the magnitude of the radiative
cooling outside the clouds decreases with altitude, leading
to a smaller descending mass-flux. This decrease continues
up until a certain level, situated at about 360 K (15 km), that
marks the transition from clear-sky radiative cooling to radia-
tive heating (Gettelman et al., 2004). Once above this level,
known as the Clear sky Level of Zero radiative Heating (C-
LZH), the majority of air originating from deep convection
is transported into the stratosphere. To examine this effect, in this paper we use a simple La-
grangian model, termed TTL detrainment model, that com-
bines a large number of back trajectory calculations with
high-resolution global fields of brightness temperatures. Our
particular focus is to determine the ensemble of trajecto-
ries that are detrained from deep convection. This ensem-
ble is then used to deduce the distribution of convective
sources and times for transport of cloud air across the TTL. The trajectories are calculated using the European Centre
of Medium-range Weather Forecast (ECMWF) ERA-Interim
re-analysis winds and radiative heating rates, derived both
under all-sky and clear-sky conditions so that the radiative
influence of clouds is established. The brightness tempera-
ture data are obtained from the CLoud Archive User Service
(CLAUS). 1
Introduction In order to evaluate the sensitivity of the results to
biases in the brightness temperature we consider a variable
offset of 1T = ±5 K. p
p
The mean 5–15 K (1–3 km) gap between the level of max-
imum convective outflow and the mean C-LZH implies that
the number of convective sources that can penetrate the C-
LZH is potentially too small to explain the large-scale up-
ward mass-flux in the Brewer-Dobson circulation. This dis-
crepancy is accounted for by considering the radiative in-
fluence of opaque clouds near their top as well as cirrus
clouds (Yang et al., 2010). The latter are omnipresent in
the TTL (e.g., Wang et al., 1996; Martins et al., 2011), gen-
erated either from the outflow of deep convective anvils or
in situ condensation (e.g., Massie et al., 2002), with life-
times of a few days, reaching horizontal scales of the order
of 1000 km (e.g., Winker and Trepte, 1998). Using a large
number of detailed radiative transfer calculations to quantify
upwelling and subsidence in cloudy and cloud-free air, Corti
et al. (2005) showed that the All-sky Level of Zero radia-
tive Heating (A-LZH) is on average about ∼355 K (14 km),
i.e., ∼5 K (1 km) lower than the C-LZH. The gap between
the A-LZH and the mean level of maximum convective out-
flow is thus reduced, facilitating a larger proportion of air to
be transported into the stratosphere. The net radiative heat-
ing associated with solar absorption by cloud tops and in-
frared heating by cirrus clouds (which within cirrus clouds
is ∼1 K day−1) allows for the rapid transport of air upwards,
up to the C-LZH, above which their radiative influence be-
comes increasingly small. According to Corti et al. (2006),
it can take as little as two weeks (a time sufficiently short for
most VSLS) for air of convective origin to reach the 370 K
surface, if the air remains inside cirrus clouds for most of the
time. In the next section we present the model, data and trajec-
tory calculations used in this study. In Sect. 3 we present our
results. We last conclude in Sect. 4. 2.1
Trajectory calculations affected by the season – the mean potential temperature is
420 K on the 100 hPa surface and 465 K on the 70 hPa sur-
face. 2003; Stohl et al., 2004; Wohltmann and Rex, 2008). Al-
though this difference is less prominent in the ERA-Interim
dataset (Monge-Sanz et al., 2007; Liu et al., 2010), it may
still be significant in reconstructing ozone profiles in the TTL
(Konopka et al., 2009; Ploeger et al., 2011). We use these back trajectories to investigate the character-
istics of convective sources for transport of cloud air across
the TTL, eventually reaching a destination in the tropics or
the extratropics at 100 or 70 hPa. A main motivation lies
in understanding how these sources influence the distribu-
tions of VSLS in the upper TTL and the lower stratosphere. The lifetimes of VSLS are by definition less than 6 months
(see e.g. WMO, 2007). Therefore, 200-day simulations are
both sufficient and necessary for our purposes. Note that 200
days is sufficiently long to sample the rapid exchanges be-
tween the tropical and extra-tropical lower stratosphere, oc-
curring at timescales faster than those associated with the
deep branch of the Brewer-Dobson circulation. Our focus
is on determining the convective sources for 2005. In or-
der that all sources in 2005 are equally sampled, we set the
launch period to cover a period between the 1st of January
2005 and the 30 June 2006. The trajectories are initialised
at 12:00 UTC every 4 days resulting in a total of 5 017 680
(138×36 360) trajectories. The horizontal (isentropic) part of the motion is obtained
from the meteorological wind fields. First extracted on a
1◦×1◦longitude/latitude grid, the wind fields are linearly in-
terpolated in the latitude, longitude and log-pressure along
the trajectories. Trajectories are then integrated in time with
a 15 min time-step. The vertical (cross-isentropic) part of the
motion is derived from radiative heating rates, Qrad, pro-
vided as 3-h averages from forecasts of temperature tenden-
cies. The vertical displacement is then given by dθ
dt =
θ
cpT Qrad,
(1) dθ
dt =
θ
cpT Qrad, (1) where θ denotes potential temperature, T temperature and cp
the specific heat capacity per unit mass at constant pressure. In general, this part of the motion is derived from diabatic
heating rates whose values can also depend on additional pro-
cesses to radiative heating. 2.1
Trajectory calculations We employ large-scale wind and temperature fields to calcu-
late an ensemble of back trajectories whose initial positions
are uniformly distributed on two iso-pressure surfaces that
lie in the upper TTL and lower stratosphere: 100 hPa and
70 hPa. The trajectories are initialised on a high-resolution
1◦×1◦longitude/latitude grid between 50◦N and 50◦S, at all
longitudes (36,360 trajectories). This range of latitudes en-
compasses the latitude range of the TTL in all seasons. On
these surfaces, the potential temperatures vary between low
values at the equator that depend on the season – the mean
January (July) potential temperature is 380 K (385 K) for the
100 hPa surface and 430 K (415 K) for the 70 hPa surface –
and large values at the poleward boundaries that are weakly The above descriptions and estimates are based on mean
vertical profiles and thus do not take into account the de-
tailed pathways of cloud air (i.e., air originating from deep
convection). These pathways are largely controlled by large-
scale horizontal advection that, in this region of the at-
mosphere, can transport cloud air along great longitudinal Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12519 0
10
20
30
40
50
60
70
80
350
355
360
365
370
375
380
time (days)
e0 (K)
A-LZH
C-LZH
(b) ï3
ï2
ï1
0
1
2
340
360
380
400
420
de/dt (K/day)
e (K)
mean 70hPa surface
mean cold point tropopause (100hPa)
C-LZH A-LZH
main convective
outflow
er 2011
(a)
0
10
20
30
40
50
60
70
80
350
355
360
365
370
375
380
time (days)
e0 (K)
A-LZH
C-LZH
(b)
Fig. 1. (a) Annual mean tropical radiative heating rates (30◦S–30◦N) represented as change in potential temperatures, calculated for all-sky
(in red) and clear-sky (in black) conditions, using the ERA-Interim dataset for 2005. (b) Time for transport from a source level, θ0, to 380 K,
calculated using the profiles shown in (a). (b) Fig. 1. (a) Annual mean tropical radiative heating rates (30◦S–30◦N) represented as change in potential temperatures, calculated for all-sky
(in red) and clear-sky (in black) conditions, using the ERA-Interim dataset for 2005. (b) Time for transport from a source level, θ0, to 380 K,
calculated using the profiles shown in (a). 2.1
Trajectory calculations Monthly mean radiative heating rates, represented as change in potential temperatures, calculated for January and July and both
all-sky (in red) and clear-sky (in black) conditions, using the ERA-Interim dataset for 2005. The vertical profiles are obtained over the
15◦S–15◦N latitude band as well as 8 other geographical regions. Africa (Af): (15◦S–20◦N)×(40◦W–20◦E); C. America (CAm): (0◦–
20◦N)×(110◦W–60◦W); S. America (SAm): (35◦S–0◦)×(75◦W–45◦W); S. Asian-Pacific (SAP): (20◦S–10◦N)×(70◦E–120◦W); N. Asian-Pacific (NAP): (10◦N–35◦N)×(70◦E–120◦W); N. Asian-Pacific Land (NAPL): (20◦N–35◦N)×(70◦E–120◦E); N. Asian-Pacific
Ocean (NAPO): NAP-NAPL; Tibetan plateau (Tib): (30◦N–35◦N)×(80◦E–95◦E). The “+” and “−” signs on the horizontal axis respec-
tively stand for +1 and −1 K day−1. The shift between two successive profiles is 4 K day−1. 15N15S
Af
CAm
SAm
SAP
NAP
NAPO
NAPL
Tib
ï
+
0
+
0
ï
0 +
ï
0 +
ï
0
ï
+
0
ï
+
0
ï
+
0
ï
+
0 +
ï
350
360
370
380
390
e (K)
Heating rate (K/day)
15N15S
Af
CAm
SAm
SAP
NAP
NAPO
NAPL
Tib
ï 0 +
0
ï
+
0 +
ï
0
ï
+
0 +
ï
0
ï
+
0 +
ï
0 +
ï
0 +
ï
350
360
370
380
390
Heating rate (K/day)
e (K)
JAN
JUL Fig. 2. Monthly mean radiative heating rates, represented as change in potential temperatures, calculated for January and July and both
all-sky (in red) and clear-sky (in black) conditions, using the ERA-Interim dataset for 2005. The vertical profiles are obtained over the
15◦S–15◦N latitude band as well as 8 other geographical regions. Africa (Af): (15◦S–20◦N)×(40◦W–20◦E); C. America (CAm): (0◦–
20◦N)×(110◦W–60◦W); S. America (SAm): (35◦S–0◦)×(75◦W–45◦W); S. Asian-Pacific (SAP): (20◦S–10◦N)×(70◦E–120◦W); N. Asian-Pacific (NAP): (10◦N–35◦N)×(70◦E–120◦W); N. Asian-Pacific Land (NAPL): (20◦N–35◦N)×(70◦E–120◦E); N. Asian-Pacific
Ocean (NAPO): NAP-NAPL; Tibetan plateau (Tib): (30◦N–35◦N)×(80◦E–95◦E). The “+” and “−” signs on the horizontal axis respec-
tively stand for +1 and −1 K day−1. The shift between two successive profiles is 4 K day−1. ECMWF model, obtained using statistical assumptions about
the cloud distribution within the mesh. This calculation can
thus not distinguish between the heating occurring inside the
clouds from that occurring outside the clouds. We assume
that as long as the trajectories are situated at the top or above
deep convective clouds, the cloud component of the radiative
heating is related to the effect of clouds on their environment. 2.1
Trajectory calculations transport between a source level in potential temperature, θ0,
and the 380 K level (see Fig. 1b). These differences are espe-
cially important below 365 K where the estimated transport
time is strongly dependent on the value of θ0, diverging as θ0
approaches the mean LZH (in either clear- or all-sky condi-
tions) that acts as a barrier for transport between the mid and
upper troposphere. ECMWF model, obtained using statistical assumptions about
the cloud distribution within the mesh. This calculation can
thus not distinguish between the heating occurring inside the
clouds from that occurring outside the clouds. We assume
that as long as the trajectories are situated at the top or above
deep convective clouds, the cloud component of the radiative
heating is related to the effect of clouds on their environment. We emphasize the use of radiative (instead of total dia-
batic) heating rates for the vertical part of the cloud-free
motion. This is because the rapid, upward convective mo-
tion between the boundary layer and detrainment occurs over
sub-grid horizontal scales of a few kilometres. This motion
is parameterized within the ECMWF model and averaged
within the mesh. The resolved vertical velocity or, equiva-
lently, the total diabatic heating rate (including the release
of latent heat), is, within the regions of convection, positive
between the boundary layer and the tropopause. Thus, the
descending air parcel motions associated with cloud-free re-
gions between deep convective clouds are not represented. This lack of representation may lead to erroneous transport
in the convective regions of the tropical troposphere. The above estimates do not take into account the horizon-
tal part of the motion. They nevertheless point to the key
role that cloud radiation has on transport across the TTL. In
order to obtain a comprehensive quantification of the radia-
tive influence of clouds on transport across the TTL, we here
consider both all-sky and clear-sky radiative heating rates for
the vertical part of the motion. Such a quantification has to
some extent been examined in Ploeger et al. (2010) where
it is found that vertical transport is indeed faster when the
radiative influence of clouds is taken into account. Ploeger
et al. (2010), however, focus on back trajectories arriving on
fixed levels of θ0 that are not related to the potential temper-
ature at which air of convective origin detrains. 2.1
Trajectory calculations However, as long as a trajectory
remains in cloud-free air, the component of heating that is
associated with the release of latent heat can be discarded
while the contribution of heat transfer by turbulent motion
and diffusion was previously found to be small (Fueglistaler
et al., 2009b). The back trajectories are computed in an isentropic co-
ordinate system (diabatic trajectories) with TRACZILLA, a
modified version of FLEXPART (Stohl et al., 2005; Pisso
and Legras, 2008), using analysis (at 00:00, 06:00, 12:00
and 18:00 UTC), 3-h forecasts (at 03:00, 09:00, 15:00, and
21:00 UTC) and 9-h forecasts (at 09:00 and 21:00 UTC)
from the European Centre of Medium-range Weather Fore-
cast (ECMWF) ERA-Interim re-analysis dataset (T255 spec-
tral resolution, 60-level hybrid vertical coordinates and 12-h
4D-Var assimilation; see Dee et al., 2011). Diabatic trajec-
tories have been found to be less dispersive than trajecto-
ries obtained by kinematic models in which transport is de-
rived from three-dimensional wind fields (Schoeberl et al., The radiative heating rates can be calculated in both clear-
sky and all-sky conditions in which case the radiative effect
of different kinds of clouds is included. Calculating the con-
tribution of clouds on the radiative heating rates can become
quite involved, particularly in regions where both optically
thick anvil clouds and thin cirrus clouds co-exist. The un-
certainties in the radiative heating rates are thus larger in the
lower TTL (see Fig. 7 in Fueglistaler et al., 2009b). The con-
tribution of clouds to the radiative heating rates is, within the Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12520 15N15S
Af
CAm
SAm
SAP
NAP
NAPO
NAPL
Tib
ï
+
0
+
0
ï
0 +
ï
0 +
ï
0
ï
+
0
ï
+
0
ï
+
0
ï
+
0 +
ï
350
360
370
380
390
e (K)
Heating rate (K/day)
15N15S
Af
CAm
SAm
SAP
NAP
NAPO
NAPL
Tib
ï 0 +
0
ï
+
0 +
ï
0
ï
+
0 +
ï
0
ï
+
0 +
ï
0 +
ï
0 +
ï
350
360
370
380
390
Heating rate (K/day)
e (K)
JAN
JUL
Fig. 2. 2.2
Detrainment The primary consequence of our algorithm is to eliminate
the encounters of trajectories with clouds in the stratosphere. For it is now recognised that convective events that pene-
trate the tropopause are rare, representing less than 0.5 % of
the total number of convective events (Liu and Zipser, 2005;
Fu et al., 2007) and are therefore unlikely to affect the to-
tal transport of mass across the tropopause. A quantity that
could be more sensitive to overshooting events is the distri-
bution of water vapour. However, it is now established that
in the lower stratosphere, its distribution can be successfully
reconstructed using large-scale wind and temperature fields,
both globally (see e.g. Fueglistaler et al., 2005; James et al.,
2008; Liu et al., 2010) and locally (Schiller et al., 2009). This
suggests that most of its variability is controlled by slow de-
hydration induced by the large-scale motion. Our main aim is to determine and characterise the sub-
ensemble of trajectories that have encountered Convec-
tive Sources (CS), thereafter called the CS-TTL ensem-
ble. To that end, we employ high-resolution fields of cloud
top heights, estimated using satellite brightness tempera-
ture (BT) measurements based on the infra-red window
(mean 10.8 µm channel), obtained from CLAUS at 1/3◦×
1/3◦spatial resolution and 3-h temporal resolution (Hodges
et al., 2000) that are mapped along the trajectories using
piecewise constant interpolation. The use of BT to measure
cloud top heights is based on the standard assumption that
the temperature at the top of the cloud is equal to that of the
environment at this location. Note that CLAUS maps all types of clouds. However,
here, we are only interested by the anvils produced by deep
convection. This distinction cannot be made in the absence of
available cloud classification at a global scale or information
from other channels. The presence of high-altitude, semi-
transparent cirrus situated above the anvil may therefore in-
troduce a possible bias in the cloud top heights. Other bi-
ases are related to the non-equilibrium evolution of the cloud
that leads to temperature differences and cloud heterogene-
ity within the pixel (Sherwood et al., 2004). In order to take
into account these sort of biases, we consider a variable off-
set, 1T , to the brightness temperatures that ranges within the
±5 K interval (see Sect. 2.3 for more details on the CS-TTL
ensembles that we obtain). 2.1
Trajectory calculations Figure 2 shows the monthly mean vertical profiles of the
radiative heating rates calculated from the EI dataset, for Jan-
uary and July 2005, over different regions and both clear-sky
and all-sky conditions. It is clear that over the 15◦S–15◦N
latitude band, the monthly profile differences are weak. There are, however, significant differences over a number
of regions. These differences are associated with the cy-
cle of convection. In particular, during active periods of As noted in the introduction, clouds can enhance the net
tropical radiative heating rates (see e.g. Yang et al., 2010). This enhancement is reflected in the annual mean verti-
cal tropical profiles of the radiative heating rates, shown in
Fig. 1a, obtained for clear-sky and all-sky conditions from
the ERA-Interim dataset for 2005. The differences between
the two profiles result in different estimates for the time for Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ 12521 A. Tzella and B. Legras: A Lagrangian view of transport across the TTL A. Tzella and B. Legras: A Lagrangian view of transport across the TTL convection, both the C-LZH and the A-LZH are lower, with
the latter exhibiting a larger shift downwards. This is not so
much the case for the southern Asian-Pacific region (SAP)
because convection is active during both boreal winter and
summer. It is clearly the case for central America (CAm) in
which convection is not prevalent during boreal winter but
is present during boreal summer and the regions of southern
America (SAm) and Africa (Af) in which convection rarely
takes place during boreal summer but is active during bo-
real winter. In the northern Asian-Pacific region (NAP), con-
vection is only active during the period of monsoon. In this
case, both the A-LZH and the C-LZH are higher by about
5 K with respect to their SAP counterparts. The NAP val-
ues are the combined contribution from the oceanic part of
the NAP (which exhibits a lower C-LZH and A-LZH) and
the continental part of the NAP (which exhibits an A-LZH of
362 K which is well above its standard value). Extreme val-
ues of 370 K are reached above the Tibetan plateau (Tib) for
both the A-LZH and the C-LZH. This pattern is associated
with the sloping up of the LZH in the subtropics (see Fig. 2
of Fueglistaler et al., 2009a). 2.1
Trajectory calculations This suggests that, during bo-
real summer, part of the convective sources for transport of
cloud air across the TTL should be located at potential tem-
peratures that are higher than those obtained during boreal
winter. A trajectory is identified as a member of the CS-TTL en-
semble if the time history of its temperature over the duration
of the back-trajectory has at some point been larger than the
temperature on the top of the cloud. In this case, the last en-
counter with a cloud is given by the first time (in backward
time) at which the parcel’s temperature becomes larger than
the cloud top temperature. The remaining part of the back
trajectory is thereafter ignored. For the above rule to be well-posed, the cloud top height
needs to be unambiguously defined in terms of temperature. This is indeed the case within the tropics where the tem-
perature decreases monotonically with height until a distinct
minimum is reached at approximately 380 K or 100 hPa. We
therefore impose two further rules. The first rule is that the
parcel’s potential temperature at the encounter point is less
than 380 K i.e., the position of the air parcel at this point
lies below the tropical tropopause. The second rule is that
the parcel’s latitudinal position at the encounter point is con-
strained within (30◦S–30◦N) except for the boreal summer
season during which it is constrained within (30◦S–35◦N). In practice, the precise value of this boundary is not impor-
tant: because of subsidence in the subtropics, less than 5%
of the trajectories actually encounter a cloud at higher lat-
itudes. The northward extension of the northern boundary
during boreal summer is a mere consequence of the Asian
Monsoon that drives continental convection towards higher
latitudes. Atmos. Chem. Phys., 11, 12517–12534, 2011 2.4
Remaining “free” trajectories The remaining parcels have never encountered a cloud at the
end of their 200-day back-trajectory. The majority of these
“free” parcels were, at the beginning of their back-trajectory,
located within the extra-tropics (about 80 % and 65 % for
launches at 100 hPa and 70 hPa, respectively). Under all-
sky conditions, the majority of “free” parcels are, at the end
of their back-trajectory, located at higher parts of the strato-
sphere (θ>400 K), mostly within the extra-tropics, entrained
within the (reverse) Brewer-Dobson circulation (about 70 %
and 75 %). Conversely, under clear-sky conditions, the cor-
responding proportions are smaller (about 40 % and 55 %). Figure 3 shows that, when the trajectories are initialised at
100 hPa, the CS-TTL trajectories represent 80 % of the entire
set of trajectories for all-sky conditions and 72 % for clear-
sky conditions. Half of the CS-TTL parcels have encoun-
tered a convective source within the last 40 (for 1T = −5 K)
and 51 days (for 1T = 5 K) for all-sky conditions. For clear-
sky conditions, the corresponding time is 75 days. The
proportion of CS-TTL trajectories that have previously en-
countered a convective source between 90 and 200 days ago
is non-negligible for all-sky conditions (17–30 %) and even
more so for clear-sky conditions (39 % for CLRSKY-1T 0). When the parcels are initialised at 70 hPa, the CS-TTL trajec-
tories represent a smaller proportion of the entire set of tra-
jectories. This is due to the larger distance between the con-
vective sources and the initial level as well as the larger pro-
portion of back trajectories that end up in the extra-tropical
stratosphere. p
g p
p
The difference between all-sky and clear-sky conditions
is particularly significant when looking at the proportion of
“free” parcels that, at the end of their back trajectory, are con-
centrated below the 360 K surface. For trajectories initially
launched at 100 hPa, the corresponding proportions are no-
tably smaller for all-sky conditions (6–11 %) than for clear-
sky conditions (26 %). This large difference between all-
sky and clear-sky conditions implies that the region near the
mean tropical C-LZH is a sort of “stagnation” region. As we
shall see in Sect. 3.2, air parcels that are detrained within this
region can take a long time to exit from it. 2.2
Detrainment The here described model, that we refer to as the TTL de-
trainment model, was previously introduced, within a dif-
ferent context, by Nawrath (2002) and James et al. (2008)
to reconstruct distributions of water vapour in both the tro-
posphere and the stratosphere. In this paper, we use this
model as a way to identify the global distribution of con-
vective sources and times for transport of cloud air across
the TTL. This distribution is closely related to the distribu-
tion of sources in the boundary layer. At the same time, the
distribution of times for transport of air into the upper TTL is
expected to be similar for air originating from the boundary
layer and air originating from the sources of convection. This
is because the parcels’ motion between the boundary layer Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ 12522 A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 0
20 40 60 80 100120140160180200
0
10
20
30
40
50
60
70
80
90
100
time (days)
probability (%)
ALLSKY−DT0
ALLSKY−DT5
ALLSKY−DT−5
CLRSKY−DT0
Fig. 3. Cumulative proportion of CS-TTL trajectories plotted as a
function of time for transport of air between convective sources and
the 100 hPa (thick lines) and 70 hPa (thin lines) surfaces. Results
obtained from back trajectories, calculated in both clear-sky and
all-sky conditions where different thermal biases were taken into
account (see text for more details). The trajectories were launched
between the beginning of 2005 and the middle of 2006, with cloud
encounters restricted to 2005. 0
20 40 60 80 100120140160180200
0
10
20
30
40
50
60
70
80
90
100
time (days)
probability (%)
ALLSKY−DT0
ALLSKY−DT5
ALLSKY−DT−5
CLRSKY−DT0 and the point of detrainment is characterised by a rapid, ver-
tical upward transfer that lasts a few tens of minutes (or at
most several hours in the case of a thick anvil). Making the
general assumption that the parcels that reach heights near
the cloud top are those parcels that are less diluted by entrain-
ment of environmental air, we deduce that, at the point of de-
trainment, the CS-TTL parcels’ composition in non-soluble
tracers is similar to the composition of the boundary layer at
the same horizontal location. We note that a modified version of the TTL detrainment
model has recently been employed by Wright et al. 2.2
Detrainment (2011)
to examine the relative contribution to stratospheric water
vapour of different regions within South-East Asia during bo-
real summer. The main modification appears in the vertical
motion of the trajectories: instead of radiative heating rates,
Wright et al. (2011) employed total diabatic heating rates. For reasons discussed in Sect. 2.1, we have chosen radiative
heating rates in order to better represent the motion outside
clouds. For the sake of completeness, results obtained using
total diabatic heating rates are briefly discussed at the end of
Sects. 3.1 and 3.2. Fig. 3. Cumulative proportion of CS-TTL trajectories plotted as a
function of time for transport of air between convective sources and
the 100 hPa (thick lines) and 70 hPa (thin lines) surfaces. Results
obtained from back trajectories, calculated in both clear-sky and
all-sky conditions where different thermal biases were taken into
account (see text for more details). The trajectories were launched
between the beginning of 2005 and the middle of 2006, with cloud
encounters restricted to 2005. 2.3
CS-TTL trajectory ensembles and their
characteristics For each initial level, we perform two sets of simulations. The first one is performed using all-sky (ALLSKY) radiative
heating rates and the second one using clear-sky (CLRSKY)
radiative heating rates. For the all-sky simulations, we con-
sider a variable offset to the brightness temperature of 1T =
±5 K that takes into account the presence of biases in the
brightness temperatures (see also Sect. 2.2). It also tests the
sensitivity of the results to such biases. No offset is con-
sidered for the clear-sky calculation. We thus obtain a set
of four CS-TTL ensembles that we label as ALLSKY-1T 0,
ALLSKY-1T5, ALLSKY-1T-5 and CLRSKY-1T 0. Atmos. Chem. Phys., 11, 12517–12534, 2011 2.4
Remaining “free” trajectories Equivalently, it
takes a long time for back trajectories to encounter a source
of convection within this region. For these “free” trajectories,
the necessary time exceeds 200 days. Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12523 A. Tzella and B. Legras: A Lagrangian view of transport across the TTL Table 1. Seasonal mean characteristics of convective sources and times for transport of air between detrainment and launch. Calculations
made using the ALLSKY-1T 0 trajectory ensemble, launched at 100 hPa. The values for the median, µ1/2, and standard deviation, σ, are
given in parenthesis. Table 1. Seasonal mean characteristics of convective sources and times for transport of air between detrainment and launch. Calculations
made using the ALLSKY-1T 0 trajectory ensemble, launched at 100 hPa. The values for the median, µ1/2, and standard deviation, σ, are
given in parenthesis. DJF
MAM
JJA
SON
CS-TTL parcels, %
27
27
22
23
Cloud Temperature, K (µ1/2, σ)
205 (205, 9)
205 (205, 9)
205 (205, 9)
205 (205, 9)
Parcel potential temperature, K (µ1/2, σ)
354 (353, 3.72)
354 (353, 3.6)
357 (356, 6.2)
353 (352, 5.3)
Transit-time, days (µ1/2, σ)
59 (44, 47)
61 (46, 47)
62 (51, 43)
55 (42, 43) Table 2. Same as Table 1 but this time the focus is on the regional mean characteristics of convective sources and transport times. Table 2. Same as Table 1 but this time the focus is on the regional mean characteristics of convective sources and transport times. Africa
N. Asian-Pacific
S. Asian-Pacific
C. America
S. America
CS-TTL parcels, %
10
22
50
6
5
Cloud Temperature, K (µ1/2, σ)
201 (200, 8.6)
205 (205, 9.5)
206 (206, 8.7)
204 (204, 8.3)
203 (203, 7.4)
Parcel potential temperature, K (µ1/2, σ)
354 (354, 5.5)
357 (356, 5.5)
353 (352, 3.3)
353 (352, 5.4)
355 (353, 5.3)
Transit-time, days (µ1/2, σ)
61 (47, 46)
61 (50, 43)
58 (43, 46)
58 (45, 44)
61 (47, 46) Table 2. Same as Table 1 but this time the focus is on the regional mean characteristics of convective sources is time the focus is on the regional mean characteristics of convective sources and transport times. cloud within a given grid-box, if all regions were acting as
sources of equal strength uniformly during 2005 (see also
Berthet et al. 3
Results We use the CS-TTL trajectory ensembles to identify the
source regions for transport of cloud air into the upper TTL
and lower stratosphere. In order to characterise vertical trans-
port across the TTL, we calculate the distribution of times
for cloud air to reach its destination (i.e., the initial location
of the back trajectory) or a particular level for the first time
(in forward time). Finally, we determine the distribution of
cloud air at its destination for different ranges of values for
the transport times. Throughout the rest of this paper, we
concentrate on those CS-TTL trajectories that are detrained
during 2005 (65 % of the CS-TTL ensemble for both all-sky
and clear-sky conditions). The remaining CS-TTL trajecto-
ries that have either detrained during 2004 or 2006 are dis-
carded. Berthet et al. (2007) have previously considered the sea-
sonal variations of the distribution of source regions for
transport of air from the boundary layer to the tropopause
region. Here, we focus on the density distribution of source
regions for transport of cloud air across the TTL and con-
sider both the seasonal (1t =3 months) and daily variations
(1t = 1 day, whereby each day starts at 00:00 UTC). The
daily variations are useful to capture individual convective
sources which can thereafter be classified according to their
intensity. By employing a daily resolution we thus neglect
any variations associated with the diurnal cycle. We resolve
the source distribution on a 5◦×5◦longitude/latitude grid in
order to obtain meaningful statistics. 2.4
Remaining “free” trajectories (2007) where a similar normalisation is em-
ployed). We choose this normalisation in order to measure
the relative importance of different regions for transporting
cloud air across the TTL. 3.1
Convective sources for transport of cloud air into
the stratosphere Figure 4 shows the seasonal variations of the density
distribution, ρ100hPa, of the locations where trajectories
have detrained from clouds and subsequently arrived at
100 hPa. The results are calculated from the ALLSKY-1T 0
and CLRSKY-1T 0 trajectory ensembles for boreal winter,
spring, summer and fall seasons. The distribution of sources
is characterized by strong geographical localization and is
consistent with the well-known locations of deep tropical
convection (see also e.g. Gettelman et al., 2002; Hatsushika
and Yamazaki, 2003; Gettelman et al., 2004; Fueglistaler
et al., 2004; Levine et al., 2007). During boreal winter, the
local maxima are over central Africa, the southern Asian-
Pacific and southern America. The same three regions are
also prominent during the boreal spring and fall seasons,
though other regions, such as the northern Asian-Pacific and 3.1.1
Horizontal distributions For each launch level p, we determine the distribution of con-
vective sources, ρ(r,t), for transport of cloud air into the
stratosphere. We do this by calculating the ratio of the num-
ber of CS-TTL trajectories that encounter a cloud within the
grid-box located at r = (λ,φ), where λ is the longitude and
φ is the latitude, and time interval [t,t +1t] to a normalisa-
tion factor, N(φ,1t). The value of N(φ,1t) depends on the
latitude φ and is given by the product of the grid-box area
relative to the area of the tropics, the time-length 1t, relative
to the period concerned (here, 2005) and the total number
of CS-TTL trajectories during this period. N(φ,1t) denotes
the expected number of trajectories that would encounter a Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12524 Table 3. Same as Table 1 but this time the focus is on all four CS-TTL ensembles, obtained for transport in all-sky and clear-sky conditions. ALLSKY-1T 0
ALLSKY-1T5
ALLSKY-1T −5
CLRSKY-1T 0
Cloud Temperature, K (µ1/2, σ)
205 (205, 9)
203 (203, 8.3)
206 (206, 9.5)
196 (195, 5.6)
Parcel potential temperature, K (µ1/2, σ)
354 (353, 4.7)
353 (352, 3.5)
356 (354, 6.3)
359 (358, 3.6)
Transit-time, days (µ1/2, σ)
59 (46,45)
64 (51,46)
53 (40,44)
83 (75,49)
all-sky
clear-sky
Fig. 4. Seasonal variations of the distribution ρ100hPa of the horizontal locations where trajectories, initially launched at 100 hPa, have
intersected clouds within the previous 200 days for the boreal winter (DJF), spring (MAM), summer (JJA), and fall (SON) seasons in
2005. The distributions on the left panels are calculated under all-sky conditions from the ALLSKY-1T 0 trajectory ensemble, while
those on the right panels are calculated under clear-sky conditions, using the CLRSKY-1T 0 ensemble. The distributions are binned in a
5◦×5◦longitude/latitude grid. The solid boxes define a set of geographical regions which are (from left to right): Af, NAP, NAPL, Tib, SAP,
CAm and SAm as defined in Fig. 2. is time the focus is on all four CS-TTL ensembles, obtained for transport in all-sky and clear-sky conditions. Table 1 but this time the focus is on all four CS-TTL ensembles, obtained for transport in all-sky and clear-sky Fig. 4. 3.1.2
Localization of the horizontal distributions The distribution of convective sources is highly localized not
only in space but also in time. The spatio-temporal localisa-
tion of the daily-varying ρ(r,t) can be analysed by consider-
ing the fraction of horizontal locations and times that have a
density distribution whose value exceeds a given threshold,
ϱ. More precisely, we define: (a) (a)
0
5
10
15
20
25
0
10
20
30
40
50
60
70
80
90
100
Probability (%)
Space−Time Volume Fraction (%)
DJF
MAM
JJA
SON
(b) A(ϱ) = 1
Z
T
dt
Z
σ
drIϱ(r,t),
(2a) (2a) where Iϱ is the indicator function: Iϱ(r,t) =
1, if ρ(r,t) ≥ϱ,
0,
otherwise,
(2b) (2b) (b) and denotes the total space-time volume. Its value is given
by =
R
T dt
R
σ drI0(r,t), where σ denotes the region in
which the sources of convection are resolved (here, the trop-
ics) and T the time period concerned (here, the year 2005). It follows that A(0) = 1. Fig. 5. Localization of the density distribution ρ100hPa, as mea-
sured by the cumulative fraction Pϱ(A), defined in Eq. (3.1.2). (a)
Ensemble characteristics of Pϱ(A) obtained from four CS-TTL tra-
jectory ensembles, all launched at 100hPa. (b) Seasonal characteris-
tics of Pϱ(A) obtained from the ALLSKY-1T 0 ensemble by con-
sidering trajectories detrained during boreal winter (DJF), spring
(MAM), summer (JJA) and fall (SON) seasons in 2005. For both
(a) and (b) are plotted the mean (solid grey) and mean±standard
deviation (dotted grey) of P˜ϱ(A) obtained from 1000 realisations
of ˜ρ100hPa produced under uniform random conditions. Thus, by considering increasingly large values of ϱ, we
obtain the fraction of space-time volume associated with in-
creasingly intense sources. The fraction of trajectories asso-
ciated with A(ϱ) is given by P(ϱ) =
Z
Iϱ(r,t)ρ(r,t)drdt. (2c) (2c) randomly distributing the same number of cloud encounters
in in both space and time. By definition A(ϱ) is a monotonically decreasing function
of ϱ and thus there exists a unique inverse, ϱ(A). Employing
this inverse, we compose Pϱ(A) ≡(P ◦ϱ)(A). A function of
the space-time volume, Pϱ(A) measures how localized the
source distribution is. It can be shown that Pϱ(A) is a mono-
tonically increasing function of A with limA→0Pϱ = 0 and
limA→1Pϱ = 1. The value of A for which Pϱ(A) = 0.5 or
0.99 indicate the degree of localization of the distribution. 3.1.1
Horizontal distributions Legras: A Lagrangian view of transport across the TTL 12525 0
5
10
15
20
25
0
10
20
30
40
50
60
70
80
90
100
Probability (%)
Space−time Volume Fraction (%)
ALLSKY−DT0
ALLSKY−DT5
ALLSKY−DT−5
CLRSKY−DT0
(a)
0
5
10
15
20
25
0
10
20
30
40
50
60
70
80
90
100
Probability (%)
Space−Time Volume Fraction (%)
DJF
MAM
JJA
SON
(b)
Fig. 5. Localization of the density distribution ρ100hPa, as mea-
sured by the cumulative fraction Pϱ(A), defined in Eq. (3.1.2). (a)
Ensemble characteristics of Pϱ(A) obtained from four CS-TTL tra-
jectory ensembles, all launched at 100hPa. (b) Seasonal characteris-
tics of Pϱ(A) obtained from the ALLSKY-1T 0 ensemble by con-
sidering trajectories detrained during boreal winter (DJF), spring
(MAM), summer (JJA) and fall (SON) seasons in 2005. For both
(a) and (b) are plotted the mean (solid grey) and mean±standard
deviation (dotted grey) of P˜ϱ(A) obtained from 1000 realisations
of ˜ρ100hPa produced under uniform random conditions. 0
5
10
15
20
25
0
10
20
30
40
50
60
70
80
90
100
Probability (%)
Space−time Volume Fraction (%)
ALLSKY−DT0
ALLSKY−DT5
ALLSKY−DT−5
CLRSKY−DT0
(a)
0
5
10
15
20
25
0
10
20
30
40
50
60
70
80
90
100
Probability (%)
Space−Time Volume Fraction (%)
DJF
MAM
JJA
SON
(b) clouds within the Asian-Pacific region. However, this differ-
ence is smaller (within ±3 %) in other regions. 0
5
10
15
20
25
0
10
20
30
40
50
60
70
80
90
100
Probability (%)
Space−time Volume Fraction (%)
ALLSKY−DT0
ALLSKY−DT5
ALLSKY−DT−5
CLRSKY−DT0
( ) Note that the difference in the regional proportions
obtained from the ALLSKY-1T 0, ALLSKY-1T 5 and
ALLSKY-1T −5 ensembles is found to be at most 4 %
(not shown). The same is true for the regional propor-
tions obtained from the ALLSKY-1T 0 ensemble launched
at 100 hPa and 70 hPa. 3.1.1
Horizontal distributions Seasonal variations of the distribution ρ100hPa of the horizontal locations where trajectories, initially launched at 100 hPa, have
intersected clouds within the previous 200 days for the boreal winter (DJF), spring (MAM), summer (JJA), and fall (SON) seasons in
2005. The distributions on the left panels are calculated under all-sky conditions from the ALLSKY-1T 0 trajectory ensemble, while
those on the right panels are calculated under clear-sky conditions, using the CLRSKY-1T 0 ensemble. The distributions are binned in a
5◦×5◦longitude/latitude grid. The solid boxes define a set of geographical regions which are (from left to right): Af, NAP, NAPL, Tib, SAP,
CAm and SAm as defined in Fig. 2. ern Asian-Pacific (22 % and 27 %). A smaller percentage
has detrained within Africa (10 % and 13 %), and an even
smaller part comes from central and southern America (3–
6 % for both regions and ensembles; see also Table 2). For
both CS-TTL ensembles, the contribution from the Tibetan
plateau remains small (≲2.5 % and ≲3.6 % respectively, of
the total and northern Asian-Pacific boreal summer convec-
tive sources). This result is in agreement with recent work
by Park et al. (2007); James et al. (2008); Devasthale and
Fueglistaler (2010); Wright et al. (2011) but does not support
previous work by Fu et al. (2006) in which the contribution
from the Tibetan plateau is found to be more important. The
radiative influence of clouds leads to a noticeable difference
(5–6 %) in the proportion of trajectories that are detrained by equatorial America, also become important during this pe-
riod. During boreal summer, most activity takes place over
the northern Asian-Pacific and central America. Very simi-
lar distributions to the ones shown in Fig. 4 were also found
for transport from clouds to the 70 hPa surface as well as for
shorter, 60-day long trajectories (not shown). For both ALLSKY-1T 0 and CLRSKY-1T 0, we find that
trajectories are detrained all along 2005 with a slight pref-
erence for the boreal winter and spring seasons (see Ta-
ble 1 for results obtained from the ALLSKY-1T 0 ensem-
ble). Most CS-TTL trajectories have detrained within the
southern Asian-Pacific region (50 % and 44 % for all-sky and
clear-sky conditions, respectively) while a significant propor-
tion of CS-TTL trajectories has detrained within the north- Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. 3.1.3
Cloud top brightness temperatures where the LZH has a higher potential temperature, and sub-
sequently may subside back into the troposphere (see also
discussion in Devasthale and Fueglistaler, 2010). It can also
be that the fast upward motion associated with radiative heat-
ing from clouds only occurs around a selected number of
deep convective clouds. This is because cirrus clouds may
either not be present or cloud air may subside due to the
radiative cooling associated with that part of the cirrus that
is situated directly above deep convective clouds (see Hart-
mann et al., 2001). Both these mechanisms could be signif-
icant in controlling how influential a convective source will
be in transporting cloud air into the stratosphere. The cumulative histograms of BT for the selected clouds en-
countered by the CS-TTL parcels are shown in Fig. 6a for the
four trajectories ensembles, launched at 100 hPa (the same
results are obtained for simulations launched at 70 hPa and
for shorter, 60-day long trajectories). Nearly all (90 %) of
the CS-TTL parcels have detrained from very deep clouds
(with BT≤220K and BT≤203K for transport under all-sky
and clear-sky conditions, respectively). As expected, the
air parcels sample the deepest convective sources more ef-
ficiently in clear-sky than in all-sky conditions. This is be-
cause in all-sky conditions, the CS-TTL trajectories can be
detrained from convective sources that have a broader range
of brightness temperatures than in clear-sky conditions (re-
call that the mean A-LZH is lower than the mean C-LZH). To measure how sparsely distributed ρ(r,t) is within the
space occupied by clouds, we employ Pϱ|T ∗(A), a vari-
ant of Pϱ(A), introduced in Sect. 3.1.2, that describes how
sparse the source distribution is in T ∗, where T ∗is defined
as the total space-time volume with brightness temperature,
BT ≤T ∗. We can thus define A as in Eq. (3.1.2) but this time
in terms of T ∗and Iϱ|T ∗where No seasonal variations are observed in the BT cumulative
histograms (see Fig. 6b). However, some regional variations
are present (see Fig. 6a) with the deepest convective sources
located within the region of Africa, followed by the region
of southern and central America (see also Table 2). These
regional characteristics are consistent with previous observa-
tions which find that the deepest convective events occur pre-
dominantly over land, particularly above the region of Africa
(see e.g. Liu and Zipser, 2005). 3.1.2
Localization of the horizontal distributions The smaller their values are, the more localized is the source
distribution. The source distribution that is most localised is the one
obtained under clear-sky conditions. The least localised dis-
tribution corresponds to the one obtained under all-sky con-
ditions, having taken into account a thermal bias of 1T =
−5 K. This is consistent with the fact that the C-LZH is, on
average, higher than the A-LZH, leading to a smaller number
of sources that are able to detrain air at higher levels of the
TTL. Conversely, under all-sky conditions, when the ther-
mal bias becomes progressively smaller (from 1T = 5 K to
1T = 0 and then 1T = −5 K), the top of clouds become pro-
gressively raised, leading to a larger number of sources that
are able to detrain air at higher levels of the TTL. We employ Pϱ(A) to measure how localised ρ100hPa is, as
this varies daily. For comparison, Pϱ(A) is calculated for all
four CS-TTL ensembles. Figure 5a shows that a very small
(0.5–2 %) proportion of accounts for half of the trajecto-
ries (associated with the most intense sources) and 3–8 % of
accounts for nearly all (99 %) of the CS-TTL trajectories. (Nearly identical distributions are obtained both for trajecto-
ries launched at 70 hPa and for shorter, 60-day long trajecto-
ries). Note that the corresponding proportions are consider-
ably larger for the distribution ˜ρ100hPa obtained by uniformly We now employ Pϱ(A) to measure how the structure of
ρ100hPa varies with the season. In this case, denotes the
total space-time volume during a particular season. Interest-
ingly, the degree of source localisation varies very little with
the season (see Fig. 5b calculated from the ALLSKY-1T 0
ensemble). Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12526 180
200
220
240
260
0
10
20
30
40
50
60
70
80
90
100
probability (%)
brightness temperature (K)
ALLSKYïDT0
ALLSKYïDT5
ALLSKYïDTï5
CLRSKYïDT0
(a)
180
200
220
240
260
0
10
20
30
40
50
60
70
80
90
100
probability (%)
brightness temperature (K)
DJF
MAM
JJA
SON
(b)
180
200
220
240
260
0
10
20
30
40
50
60
70
80
90
100
probability (%)
brightness temperature (K)
Africa
N. AsianïPacific
S. AsianïPacific
C. America
S. America
(c)
Fig. 6. 3.1.3
Cloud top brightness temperatures Iϱ|T ∗(r,t) =
1, if ρ(r,t) ≥ϱ and BT (r,t) ≤T ∗,
0,
otherwise. (3) (3) Pϱ|T ∗(A) thus measures how the sources of transport to the
stratosphere are distributed among convective systems that
reach similar depths in the troposphere. In order to calculate Pϱ|T ∗(A), we resolve the sources on
the same grid as the BT measurements (see Sect. 2.2). This
resolution is of course too high for Pϱ|T ∗(A) to converge to
an invariant form that is insensitive to the frequency at which
the trajectories are launched (note that this is not the case for
Pϱ(A), shown in Fig. 5, which unlike Pϱ|T ∗(A), is based on
a significantly lower resolution in both space and time for
the source distribution). It is nevertheless possible to assess
the sparseness of the sources by considering the departure of
Pϱ|T ∗(A) from a reference P˜ϱ|T ∗(A) with ˜ϱ|T ∗obtained by 3.1.2
Localization of the horizontal distributions Cumulative histograms of cloud top brightness temperatures for convective sources that transport air parcels to the 100 hPa surface. (a) Results obtained for all-sky and clear-sky conditions, from ensembles ALLSKY-1T 0, ALLSKY-1T5, ALLSKY-1T-5 and CLRSKY-
1T 0. (b) Results obtained for all-sky conditions only, from the ALLSKY-1T 0 ensemble, for trajectories detrained during boreal winter
(DJF), spring (MAM), summer (JJA) and fall (SON) seasons. (c) Results obtained for all-sky conditions only, from the ALLSKY-1T 0
ensemble, for trajectories detrained in the region of Africa, north Asian-Pacific, south Asian-Pacific, central America and South America,
designated in Fig. 2. 180
200
220
240
260
0
10
20
30
40
50
60
70
80
90
100
probability (%)
brightness temperature (K)
ALLSKYïDT0
ALLSKYïDT5
ALLSKYïDTï5
CLRSKYïDT0
(a)
b bilit (%) 180
200
220
240
260
0
10
20
30
40
50
60
70
80
90
100
probability (%)
brightness temperature (K)
DJF
MAM
JJA
SON
(b)
b bilit (%) 180
200
220
240
260
0
10
20
30
40
50
60
70
80
90
100
probability (%)
brightness temperature (K)
Africa
N. AsianïPacific
S. AsianïPacific
C. America
S. America
(c) (a) (b) (c) Fig. 6. Cumulative histograms of cloud top brightness temperatures for convective sources that transport air parcels to the 100 hPa surface. (a) Results obtained for all-sky and clear-sky conditions, from ensembles ALLSKY-1T 0, ALLSKY-1T5, ALLSKY-1T-5 and CLRSKY-
1T 0. (b) Results obtained for all-sky conditions only, from the ALLSKY-1T 0 ensemble, for trajectories detrained during boreal winter
(DJF), spring (MAM), summer (JJA) and fall (SON) seasons. (c) Results obtained for all-sky conditions only, from the ALLSKY-1T 0
ensemble, for trajectories detrained in the region of Africa, north Asian-Pacific, south Asian-Pacific, central America and South America,
designated in Fig. 2. 3.1.5
Vertical distributions Also plotted
the mean (solid grey) and mean±standard deviation (dashed grey)
of P˜ϱ|T ∗(A) obtained from 1000 realisations of ˜ρ100hPa. The differ-
ences between the latter three curves is small for the range of values
plotted here. The distributions are calculated for all-sky conditions,
using the ALLSKY-1T 0 ensemble launched at 100 hPa (see text
for more details). uniformly randomly distributing the same number of cloud
encounters among horizontal locations with BT≤T ∗. uniformly randomly distributing the same number of cloud
encounters among horizontal locations with BT≤T ∗. We consider three different BT threshold values, T ∗=
215, 200 and 185 K, and calculate Pϱ|T ∗(A) from the
ALLSKY-1T 0 ensemble launched at 100 hPa. Figure 7
shows that the differences between Pϱ|T ∗(A) and the mean of
P˜ϱ|T ∗(A), obtained from 1000 realisations of ˜ϱ|T ∗, are sig-
nificant. These differences suggest that the transport of cloud
air into the stratosphere is not equally distributed among
clouds of similar cloud top BT. At the same time, the smaller
the value of T ∗is, the deeper the clouds in T ∗are and thus
they can be sampled more easily. As a result, with decreasing
T ∗, Pϱ|T ∗(A) becomes less sparse as the differences between
Pϱ|T ∗(A) and P˜ϱ|T ∗(A) become smaller. g
≤
We consider three different BT threshold values, T ∗=
215, 200 and 185 K, and calculate Pϱ|T ∗(A) from the
ALLSKY-1T 0 ensemble launched at 100 hPa. Figure 7
shows that the differences between Pϱ|T ∗(A) and the mean of
P˜ϱ|T ∗(A), obtained from 1000 realisations of ˜ϱ|T ∗, are sig-
nificant. These differences suggest that the transport of cloud
air into the stratosphere is not equally distributed among
clouds of similar cloud top BT. At the same time, the smaller
the value of T ∗is, the deeper the clouds in T ∗are and thus
they can be sampled more easily. As a result, with decreasing
T ∗, Pϱ|T ∗(A) becomes less sparse as the differences between
Pϱ|T ∗(A) and P˜ϱ|T ∗(A) become smaller. Figure 8b shows the seasonal variations of the potential
temperature histograms obtained from the ALLSKY-1T 0
ensemble, launched at 100 hPa. The potential temperatures
are nearly identically distributed for CS-TTL parcels de-
trained during the boreal winter and spring season; during
the autumn season, the histogram is similar but shifted to
slightly lower values (see also Table 1). 3.1.5
Vertical distributions 8a
for the four trajectory ensembles, launched at 100 hPa (nearly
identical results are obtained for trajectories launched at
70 hPa and for shorter, 60-day long trajectories). Under all-
sky conditions, the histograms of these potential tempera-
tures are mainly confined between 350 and 360 K. For all
1T , no encounters of clouds take place below 340 K (i.e., all
encounters take place above or near the mean level of maxi-
mum convective outflow). For 1T = 0, 10 % of the encoun-
ters occur above 360 K while only 4 % occur above 365 K. Under clear-sky conditions, the corresponding potential tem-
perature histogram is narrower, with no cloud encounters tak-
ing place below 352 K while only 5% occurring above 366 K. h
b
f h
l bi
i
h (a) (a)
0
10
20
30
40
50
60
0
20
40
60
80
100
probability (%)
space−time volume fraction (%)
(b) In the absence of thermal biases (i.e., 1T = 0), the mean
potential temperature is equal to the mean LZH in both all-
sky and clear-sky cases (see also Table 3). When we consider
a thermal bias of 1T = −5 K (equivalent to raising cloud
heights), the average is displaced by 2 K to a larger value of
potential temperature. Conversely, a displacement of 1 K to
a lower value is obtained when we consider a thermal bias
of 1T = 5 K (equivalent to lowering cloud heights). Near
the tropopause, 1θ ≈−21T . Thus, there is no direct rela-
tion between the mean displacement in potential temperature
and the mean displacement in the cloud top height. We may
speculate that the lack of an obvious such relation is a com-
bination of the effect of a transport barrier (imposed by the
LZH) and the rapid decrease of deep clouds with altitude (as
observed from BT data). Upon application of a bias on the
BTs, the barrier effect dominates the subsequent shift in the
cloud top heights. This is, perhaps, the reason why the result-
ing shift in the vertical distribution of the sources is smaller
than one would expect by solely looking at the shift in BTs. (b) Fig. 7. Localization of horizontal distributions among sources of
similar depth as measured by Pϱ|T ∗(A) obtained for (a) T ∗=
215 K (red) and (b) 200 K (yellow) and 185 K (blue). 3.1.4
Sparseness of the horizontal distributions among
increasingly deep clouds It is interesting to construct a measure of how ρ(r,t) is dis-
tributed among the space occupied by clouds. For it is not
clear that all sufficiently deep clouds will participate in the
same way in troposphere-to-stratosphere transport. In par-
ticular, large-scale horizontal advection can transport cloud
air that is detrained within a certain region into other regions Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL A. Tzella and B. Legras: A Lagrangian view of transport across the TTL A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12527 0
10
20
30
40
50
60
0
20
40
60
80
100
probability (%)
space−time volume fraction (%)
(a)
0
10
20
30
40
50
60
0
20
40
60
80
100
probability (%)
space−time volume fraction (%)
(b)
Fig. 7. Localization of horizontal distributions among sources o
similar depth as measured by Pϱ|T ∗(A) obtained for (a) T ∗=
215 K (red) and (b) 200 K (yellow) and 185 K (blue). Also plotted
the mean (solid grey) and mean±standard deviation (dashed grey
of P˜ϱ|T ∗(A) obtained from 1000 realisations of ˜ρ100hPa. The differ
ences between the latter three curves is small for the range of value
plotted here. The distributions are calculated for all-sky conditions
using the ALLSKY-1T 0 ensemble launched at 100 hPa (see tex
for more details). 0
10
20
30
40
50
60
0
20
40
60
80
100
probability (%)
space−time volume fraction (%)
(a) Note that in clear-sky conditions, the difference between
Pϱ|T ∗(A) and P˜ϱ|T ∗(A) is larger (not shown). In these con-
ditions, the number of CS-TTL parcels detrained from very
deep clouds is larger than in all-sky conditions (see Fig. 6). Therefore, the corresponding statistics are closer to their in-
variant form. The latter suggests that the invariant form of
Pϱ|T ∗(A) is more sparse than in Fig. 7. 3.1.5
Vertical distributions The histograms of the potential temperatures at which the
CS-TTL trajectories encounter a cloud are shown in Fig. 8a
for the four trajectory ensembles, launched at 100 hPa (nearly
identical results are obtained for trajectories launched at
70 hPa and for shorter, 60-day long trajectories). Under all-
sky conditions, the histograms of these potential tempera-
tures are mainly confined between 350 and 360 K. For all
1T , no encounters of clouds take place below 340 K (i.e., all
encounters take place above or near the mean level of maxi-
mum convective outflow). For 1T = 0, 10 % of the encoun-
ters occur above 360 K while only 4 % occur above 365 K. Under clear-sky conditions, the corresponding potential tem-
perature histogram is narrower, with no cloud encounters tak-
ing place below 352 K while only 5% occurring above 366 K. In the absence of thermal biases (i.e., 1T = 0), the mean
potential temperature is equal to the mean LZH in both all-
sky and clear-sky cases (see also Table 3). When we consider
a thermal bias of 1T = −5 K (equivalent to raising cloud
heights), the average is displaced by 2 K to a larger value of
potential temperature. Conversely, a displacement of 1 K to
a lower value is obtained when we consider a thermal bias
of 1T = 5 K (equivalent to lowering cloud heights). Near
the tropopause, 1θ ≈−21T . Thus, there is no direct rela-
tion between the mean displacement in potential temperature
and the mean displacement in the cloud top height. We may
speculate that the lack of an obvious such relation is a com-
bination of the effect of a transport barrier (imposed by the
LZH) and the rapid decrease of deep clouds with altitude (as
observed from BT data). Upon application of a bias on the
BTs, the barrier effect dominates the subsequent shift in the
cloud top heights. This is, perhaps, the reason why the result-
ing shift in the vertical distribution of the sources is smaller
than one would expect by solely looking at the shift in BTs. i
b h
h
l
i i
f h
i l The histograms of the potential temperatures at which the
CS-TTL trajectories encounter a cloud are shown in Fig. 3.2.1
First-entry times We now focus on the time it takes for CS-TTL parcels to first
enter (in forward time) the upper TTL and the stratospheric
“overworld”. Figure 9a shows the histograms of times for
air of convective origin to first reach the 370 K and 380 K
surfaces. The corresponding results obtained from the four
trajectory ensembles, with destination at 100 hPa. Similar
histograms are obtained for trajectories launched at 70 hPa
as well as for shorter, 60-day long trajectories (not shown). In both all-sky and clear-sky cases, the histograms are broad
and skewed, decaying exponentially at large times. The histograms obtained under all-sky conditions are char-
acterized by a pronounced peak, located at approximately 15
days, that is largely unaffected by the variable offset 1T . Note that the location of the peak is consistent with the esti-
mated time that Corti et al. (2006) obtained for cloud air to
first reach the 370 K surface, provided it stays inside a cir-
rus for most of the time. Conversely, the corresponding his-
togram obtained for clear-sky conditions is notably broader,
with a slower decay rate at large times. It is interesting to note that the above land-ocean differ-
ences are not reflected in the brightness temperatures of the
corresponding convective sources. More generally, there is
no direct relation between the mean potential temperature
of cloud encounters and the mean brightness temperature
of the corresponding convective sources (e.g. although the
deepest convective sources occur more frequently in the re-
gion of Africa, the average height of cloud encounter within
this region is not significantly different to the average height
of cloud encounter in other regions, such as the southern
Asian-Pacific region, in which, in general, convection does
not reach as high (see also Sect. 3.1.3)). The average time to first reach the 370 K surface is, de-
pending on the value of 1T , between 23 and 31 days for all-
sky conditions and 54 days for clear-sky. The corresponding
time for the 380 K surface is between 33 and 44 days for all-
sky conditions and 64 for clear-sky (see also Table 4). It is
thus clear that the radiative heating associated with clouds
significantly accelerates transport across the TTL. A. Tzella and B. Legras: A Lagrangian view of transport across the TTL A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12528 340
350
360
370
380
0
10
20
30
40
probability (%)
potential temperature (K)
ALLSKYïDT0
ALLSKYïDT5
ALLSKYïDTï5
CLRSKYïDT0
(a)
340
350
360
370
380
0
10
20
30
40
probability (%)
potential temperature (K)
DJF
MAM
JJA
SON
(b)
340
350
360
370
380
0
10
20
30
40
probability (%)
potential temperature (K)
Africa
N. AsianïPacific
S. AsianïPacific
C. America
S. America
(c)
Fig. 8. Same as Fig. 6 but this time the focus is on the histograms of potential temperatures at which encounters with convective sources
have taken place. Also shown in (c) are the histograms corresponding to trajectories detrained over the land (thin brown line) and ocean
(thick brown line) parts of the north Asian-Pacific region (respectively defined as NAPL and NAPO in Fig. 2) The histograms are calculated
using a bin size of 2 K in potential temperature. 340
350
360
370
380
0
10
20
30
40
probability (%)
potential temperature (K)
ALLSKYïDT0
ALLSKYïDT5
ALLSKYïDTï5
CLRSKYïDT0
(a) 340
350
360
370
380
0
10
20
30
40
probability (%)
potential temperature (K)
DJF
MAM
JJA
SON
(b) 340
350
360
370
380
0
10
20
30
40
probability (%)
potential temperature (K)
Africa
N. AsianïPacific
S. AsianïPacific
C. America
S. America
(c) (c) (a) (b) Fig. 8. Same as Fig. 6 but this time the focus is on the histograms of potential temperatures at which encounters with convective sources
have taken place. Also shown in (c) are the histograms corresponding to trajectories detrained over the land (thin brown line) and ocean
(thick brown line) parts of the north Asian-Pacific region (respectively defined as NAPL and NAPO in Fig. 2) The histograms are calculated
using a bin size of 2 K in potential temperature. 3.2
Timescales for transport of cloud air across the TTL
and into the lower stratosphere A similar two-peak behaviour, albeit weaker, is observed
for parcels detrained in the northern Asian-Pacific region
which is mainly active during the summer season (see
Fig. 8c). We find that the first peak is mainly due to de-
trainment over the ocean while the second peak is due to
detrainment over the land part of the northern Asian-Pacific
that can take place at latitudes higher than 20◦N. As shown
in Fig. 2, during boreal summer, these two regions have very
different profiles of heating rates: Over the ocean part of the
northern Asian-Pacific (NAPO), the heating rate profile does
not differ from the mean tropical average (see also Fig. 1a). Conversely, the differences are significant over the land part
(NAPL) with both the C-LZH and the A-LZH being shifted
upwards with this shift being more pronounced for the A-
LZH. Hence, at these higher latitudes, convection must reach
higher to contribute to upward moving air across the TTL. 3.1.5
Vertical distributions The main difference
occurs for CS-TTL parcels detrained during the summer. In
this case, the parcels’ potential temperatures appear to have
a histogram that has two peaks, the first peak being located
at about 352 K and the second one at 358 K. Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL Atmos. Chem. Phys., 11, 12517–12534, 2011 A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12529 A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 0
30
60
90
120
150
180
0
5
10
15
probability (%)
time (days)
ALLSKY−DT0
ALLSKY−DT5
ALLSKY−DT−5
CLRSKY−DT0
0
60
120
180
10
−5
10
0
10
5
(a)
0
30
60
90
120
150
180
0
5
10
15
20
25
30
probability (%)
time (days)
ALLSKY−DT0
ALLSKY−DT5
ALLSKY−DT−5
CLRSKY−DT0
0
60
120
180
10
−5
10
0
10
5
(b)
Fig. 9. Histograms showing (a) first-entry times of cloud air to the 370 K surface (solid) and 380 K surface (dotted) and (b) times for cloud air
to cross the 360–370 K layer (solid) and 360–380,K layer (dotted). Results obtained for all-sky and clear-sky conditions from four CS-TTL
trajectory ensembles, all launched at 100hPa. The histograms are calculated using a bin size of 4 days. 0
30
60
90
120
150
180
0
5
10
15
20
25
30
probability (%)
time (days)
ALLSKY−DT0
ALLSKY−DT5
ALLSKY−DT−5
CLRSKY−DT0
0
60
120
180
10
−5
10
0
10
5
(b) 0
30
60
90
120
150
180
0
5
10
15
probability (%)
time (days)
ALLSKY−DT0
ALLSKY−DT5
ALLSKY−DT−5
CLRSKY−DT0
0
60
120
180
10
−5
10
0
10
5
(a) (b) (a) Fig. 9. Histograms showing (a) first-entry times of cloud air to the 370 K surface (solid) and 380 K surface (dotted) and (b) times for cloud air
to cross the 360–370 K layer (solid) and 360–380,K layer (dotted). Results obtained for all-sky and clear-sky conditions from four CS-TTL
trajectory ensembles, all launched at 100hPa. The histograms are calculated using a bin size of 4 days. Table 4. Mean characteristics of the distributions of times for transport of cloud air out of the region below 360 K and into the 370 K and
380 K surface for the first time. Calculations made using the four CS-TTL trajectory ensembles, all launched at 100 hPa. The values for the
median, µ1/2, and standard deviation, σ, are given in parenthesis. Table 4. Mean characteristics of the distributions of times for transport of cloud air out of the region below 360 K and into the 370 K and
380 K surface for the first time. Calculations made using the four CS-TTL trajectory ensembles, all launched at 100 hPa. The values for the
median, µ1/2, and standard deviation, σ, are given in parenthesis. A. Tzella and B. Legras: A Lagrangian view of transport across the TTL ALLSKY-1T 0
ALLSKY-1T5
ALLSKY-1T-5
CLRSKY-1T 0
Exit-time from region below 360 K surface, days (µ1/2, σ)
15 (11, 16)
19 (13, 19)
12 (9, 13)
42 (32, 37)
First entry into 370 K surface, days (µ1/2, σ)
27 (23, 18)
31 (26, 20)
23 (20, 16)
54 (45, 37)
First entry into 380 K surface, days (µ1/2, σ)
39 (35, 22)
44 (39, 23)
33 (30, 20)
64 (56, 37) alternate regions of negative and positive heating rates), so
that the air parcels respectively descend and rise. The corre-
sponding variations in the vertical velocities impede the im-
mediate ascent of a number of air parcels to higher altitudes. This is particularly true for clear-sky conditions: Without
the radiative influence of cirrus clouds, the magnitudes of
the vertical velocities are in general smaller than in all-sky
conditions. As a result, parcels that are detrained below the
mean C-LZH have less possibilities to escape to regions, suf-
ficiently above the mean C-LZH, where the mean flow is
strong and ascending. When this happens, the mean flow re-
gains control over their vertical transport and the dispersion
in the vertical motion becomes smaller. This indeed explains
why the histograms in Fig. 9b are narrower than those in
Fig. 9a. Note that the possibility of long trapping times near
the LZH and in particular the C-LZH has first been reported
in an idealized study by Sherwood and Dessler (2003). The
existence of this so-called “stagnation region” has also been
observed in several trajectory studies (e.g. Fueglistaler et al. (2004); Ploeger et al. (2010)). The presence of a “stagnation
region” also explains the large number of “free” trajectories
(i.e., trajectories that have not detrained from a convective
source) which are found near the C-LZH (see Sect. 2.4). alternate regions of negative and positive heating rates), so
that the air parcels respectively descend and rise. The corre-
sponding variations in the vertical velocities impede the im-
mediate ascent of a number of air parcels to higher altitudes. This is particularly true for clear-sky conditions: Without
the radiative influence of cirrus clouds, the magnitudes of
the vertical velocities are in general smaller than in all-sky
conditions. As a result, parcels that are detrained below the
mean C-LZH have less possibilities to escape to regions, suf-
ficiently above the mean C-LZH, where the mean flow is
strong and ascending. 3.2.1
First-entry times Finally, we note that, in comparison to the case of all-sky
radiative heating rates (with 1T = 0), the use of total dia-
batic heating rates results in cloud encounters which are, on
average, at potential temperatures that are lower by about 4 K
(not shown). The radiative influence of clouds on transport across the
TTL is mainly confined to the region below the 360 K sur-
face. This is evidenced in Fig. 9b in which the histograms
of times to cross the 360–370 K and 360–380 K layers are
shown to be similar in all-sky and clear-sky conditions (note Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ 3.2.2
Transit-times The ensemble histograms of transit-times between detrain-
ment and launch are shown in Fig. 10a for air parcels
launched at 100 hPa. The longer times necessary for the air
parcels to reach their destinations (in forward time) at higher
latitudes is responsible for the larger width of the histograms
(compare with the histograms shown in Fig. 9a). The mean
transit-time is between 53 and 64 days for all-sky conditions
and 83 days for clear-sky (see also Table 3). The extensive large-scale horizontal motion that takes place
within the TTL (Holton and Gettelman, 2001; Fueglistaler
et al., 2004; Bonazzola and Haynes, 2004) ensures that, at the
lower stratosphere (at about 100 hPa), air of convective origin
is, in general, well-mixed in the longitude. The histograms,
χ(r,τ), of the destination (in forward time) of the CS-TTL
trajectories differ according to the range of values of their
transit-times. Figure 10b–c shows the seasonal and regional dependence
of transit-times. During boreal summer, air parcels are rel-
atively slower in reaching their destination on the 100 hPa
surface: only 12 % of cloud air detrained during that season
reaches its destination on the 100 hPa surface within 20 days
which is about half the amount obtained during the other
seasons. Similarly, air parcels detrained within the north-
ern Asian-Pacific region (that is mainly active during boreal
summer), particularly those detrained over land, are slow to
reach their destination on the 100 hPa surface: 15 % of cloud
air arrives within 20 days. This is to be contrasted with 25 %
of air parcels detrained in the southern Asian-Pacific region
in which early transport is the fastest (see Fig. 10b). These
differences are despite the higher potential temperatures at
which air parcels detrain during both boreal summer and the
northern Asian-Pacific region (see Fig. 8). Their slow ascent
into the upper TTL is the combined result of the monsoon an-
ticyclone that dominates the large-scale boreal summer circu-
lation within this region and the smaller, on average, tropical
radiative heating rates above approximately 365 K in com-
parison to the other seasons (see e.g. Fig. 2). We determine χ(r,τ) by calculating the ratio of the num-
ber of CS-TTL trajectories, detrained during a certain sea-
son, located within the grid-box at r and transit-times within
[τ,τ +1τ] to a normalization factor, ˜N(φ,1τ). We choose
a similar normalization to the one employed for ρ(r,t) in
Sect. A. Tzella and B. Legras: A Lagrangian view of transport across the TTL A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12530 0
30
60
90
120
150
180
0
5
10
15
probability (%)
time (days)
ALLSKYïDT0
ALLSKYïDT5
ALLSKYïDTï5
CLRSKYïDT0
(a)
0
50
100
150
200
0
5
10
15
probability (%)
time (days)
DJF
MAM
JJA
SON
(b)
0
50
100
150
200
0
5
10
15
probability (%)
time (days)
Africa
N. AsianïPacific
S. AsianïPacific
C. America
S. America
(c)
Fig. 10. (a) Ensemble, (b) seasonal and (c) regional histograms of transit-times between detrainment and launch at the 100 hPa surface. Also
shown in (c) the corresponding histogram for those trajectories detrained over the land part of the north Asian-Pacific region (brown line). Results obtained from the CS-TTL trajectory ensemble ALLSKY-1T 0. The histograms are calculated using a bin size of 4 days. 0
30
60
90
120
150
180
0
5
10
15
probability (%)
time (days)
ALLSKYïDT0
ALLSKYïDT5
ALLSKYïDTï5
CLRSKYïDT0
(a) 0
50
100
150
200
0
5
10
15
probability (%)
time (days)
DJF
MAM
JJA
SON
(b) 0
50
100
150
200
0
5
10
15
probability (%)
time (days)
Africa
N. AsianïPacific
S. AsianïPacific
C. America
S. America
(c) (b) (c) (a) Fig. 10. (a) Ensemble, (b) seasonal and (c) regional histograms of transit-times between detrainment and launch at the 100 hPa surface. Also
shown in (c) the corresponding histogram for those trajectories detrained over the land part of the north Asian-Pacific region (brown line). Results obtained from the CS-TTL trajectory ensemble ALLSKY-1T 0. The histograms are calculated using a bin size of 4 days. A. Tzella and B. Legras: A Lagrangian view of transport across the TTL When this happens, the mean flow re-
gains control over their vertical transport and the dispersion
in the vertical motion becomes smaller. This indeed explains
why the histograms in Fig. 9b are narrower than those in
Fig. 9a. Note that the possibility of long trapping times near
the LZH and in particular the C-LZH has first been reported
in an idealized study by Sherwood and Dessler (2003). The
existence of this so-called “stagnation region” has also been
observed in several trajectory studies (e.g. Fueglistaler et al. (2004); Ploeger et al. (2010)). The presence of a “stagnation
region” also explains the large number of “free” trajectories
(i.e., trajectories that have not detrained from a convective
source) which are found near the C-LZH (see Sect. 2.4). that to obtain these histograms we ignore those CS-TTL tra-
jectories that never go below 360 K). At the same time, these
histograms are considerably narrower than the histograms
shown in Fig. 9a. It thus follows that the large width of the
first-entry times are due the large dispersion in the times to
exit the region below 360 K (in forward time). This disper-
sion is more pronounced in the clear-sky case. For all-sky
conditions and 1T = 0, the mean exit time is 15 days while
for clear-sky conditions it is 42 days. It is interesting to note that the mean all-sky first-exit and
first-entry times found here are consistent with simple esti-
mates such as those shown in Fig. 1b obtained for θ0≈355 K
(recall that in all-sky conditions, the mean potential tempera-
ture at which parcels detrain is 354 K). Conversely, the corre-
sponding means obtained under clear-sky conditions cannot
be explained using these sort of estimates. We may thus conclude that the large width of the first-
entry time histograms are a result of the combined effect
of the radiative heating rates and horizontal motion around
the LZH (whose mean level in the tropics coincides with the
mean potential temperature at which the CS-TTL parcels are
detrained in both clear- and all-sky conditions; see also Ta-
ble 3). Horizontal motion can lead air parcels to alternate
regions situated just below and above the LZH (equivalent to Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL Atmos. Chem. Phys., 11, 12517–12534, 2011 3.2.2
Transit-times 3.1.1: The value of ˜N(φ,1τ) depends on the latitude φ
and is given by the product of the grid-box area relative to the
area of launch surface (50◦S, 50◦N), the transit-time length,
1τ, relative to the maximum possible transit-time (here, 200
days) and the total number of CS-TTL trajectories detrained
during the season concerned. The value of ˜N(φ,1τ) denotes
the expected number of CS-TTL trajectories that would be
found within a grid-box if all CS-TTL trajectories had en-
countered a convective source with equal probability during
the last 200 days (the length of the trajectories). Figure 11 shows χ100hPa calculated from the ALLSKY-
1T 0 trajectory ensemble, launched at 100 hPa, for trajecto-
ries detrained during boreal winter (DJF) and summer (JJA). For both seasons we can identify three spatial regimes for
χ(r,τ). For small transit times (τ ≲15 days), the distribu-
tion of the CS-TTL parcels at the 100 hPa surface are local-
ized, with the local maxima located at or near the convective
source regions (see also Fig. 4). This regime corresponds to
about a tenth of the CS-TTL parcels (13 and 7 % for parcels
detrained during DJF and JJA, respectively). For interme-
diate transit-times (τ ≈15–60 days), the distributions of the
CS-TTL parcels are quasi-homogeneous within nearly the Finally, we note that, in comparison to the case of all-
sky radiative heating rates (with 1T = 0), the use of total
diabatic heating rates results in first-entry and transit-times
which are, on average, shorter by about 4 days (not shown). Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12531 DJF
JJA
0-15 days
15-60 days
60-200 days
Fig. 11. Distribution, χ100hPa, of the horizontal locations of trajectories that have intersected clouds within the previous 15 days (top),
between 15 and 60 days (middle) and between 60 and 200 days (bottom) on the 100 hPa launch surface. The distributions are calculated for
trajectories detrained during the 2005 boreal winter (left) and boreal summer (middle) using the ALLSKY-1T 0 trajectory ensemble. The
distributions are binned in a 5◦×5◦longitude/latitude grid and the histograms are calculated using a bin size of 5 degrees. 3.2.2
Transit-times The corresponding
histograms showing the latitudinal position of CS-TTL trajectories detrained during boreal winter (solid) and summer (dashed) on the 100 hPa
surface, both the total (in black) and for different ranges of values for the transit-times, τ (in red). DJF
JJA
0-15 days
15-60 days
60-200 days
Fig. 11. Distribution, χ100hPa, of the horizontal locations of trajectories that have intersected clouds within the previous 15 days (top),
between 15 and 60 days (middle) and between 60 and 200 days (bottom) on the 100 hPa launch surface. The distributions are calculated for
trajectories detrained during the 2005 boreal winter (left) and boreal summer (middle) using the ALLSKY-1T 0 trajectory ensemble. The
distributions are binned in a 5◦×5◦longitude/latitude grid and the histograms are calculated using a bin size of 5 degrees. The corresponding
histograms showing the latitudinal position of CS-TTL trajectories detrained during boreal winter (solid) and summer (dashed) on the 100 hPa
surface, both the total (in black) and for different ranges of values for the transit-times, τ (in red). DJF DJF 0-15 days 0-15 days JJA Fig. 11. Distribution, χ100hPa, of the horizontal locations of trajectories that have intersected clouds within the previous 15 days (top),
between 15 and 60 days (middle) and between 60 and 200 days (bottom) on the 100 hPa launch surface. The distributions are calculated for
trajectories detrained during the 2005 boreal winter (left) and boreal summer (middle) using the ALLSKY-1T 0 trajectory ensemble. The
distributions are binned in a 5◦×5◦longitude/latitude grid and the histograms are calculated using a bin size of 5 degrees. The corresponding
histograms showing the latitudinal position of CS-TTL trajectories detrained during boreal winter (solid) and summer (dashed) on the 100 hPa
surface, both the total (in black) and for different ranges of values for the transit-times, τ (in red). day, December 5, 2011
whole 100 hPa surface between the tropics (30◦S, 30◦N). Notice the appearance of a local maximum in the region
in which the monsoon anticyclone dominates during boreal
summer. This is because air parcels are temporarily trapped
by the monsoon anticyclone. Conversely, during boreal win-
ter, the region over the southern Asian-Pacific (particularly
the regions of Indonesia and western Pacific) are charac-
terized by rapid ascent (see e.g. Fig. 10) and consequently
no such maximum exists. 3.2.2
Transit-times This intermediate regime corre-
sponds to about half of the CS-TTL parcels (49 and 52 %
for parcels detrained during DJF and JJA, respectively). For
large transit-times (τ ≈60–200 days), the CS-TTL parcels
are mostly present in the extra-tropics, within which they are
quasi-homogeneously distributed. This regime corresponds
to about four tenths of the CS-TTL parcels (38 and 41 % re-
spectively, for parcels detrained during DJF and JJA). overcome for air of convective origin to eventually reach
the upper TTL and lower stratosphere. In this study, we
have employed a novel Lagrangian approach that combines
a large number of diabatic back trajectory calculations (in
both clear-sky and all-sky conditions) with global fields of
brightness temperatures in order to analyse the combined ef-
fect of cloud heating and large-scale horizontal motion on
the transport of air across the TTL. The result is a quanti-
tative picture of the seasonal and regional characteristics of
convective sources and times for transport of air into the up-
per TTL and lower stratosphere. We have shown that the lower, on average, level of A-LZH
(in which the radiative heating of clouds is included) and the
larger, in general, heating rates, both associated with cirrus
clouds, facilitate the rapid upwelling of air across the TTL. Focusing on the ensemble of trajectories that have encoun-
tered a source of convection during 2005, we find that the
majority of the trajectories that reach the upper TTL have
encountered a source of convection near the mean A-LZH. The fluctuating nature of the latter combined with horizontal
motion in this region result in a large dispersion in the ver-
tical transport times which is reflected in the corresponding
time distributions that are both wide and skewed (albeit less
wide than the distributions obtained in clear-sky conditions). Atmos. Chem. Phys., 11, 12517–12534, 2011 The publication of this article is financed by CNRS-INSU. The publication of this article is financed by CNRS-INSU. A. Tzella and B. Legras: A Lagrangian view of transport across the TTL A. Tzella and B. Legras: A Lagrangian view of transport across the TTL The mean time to first reach the 370 K surface is ≈27 days,
which is half the time obtained under clear-sky conditions. The distribution has a pronounced peak that is located at ≈15
days. The latter time is consistent with the estimate that Corti
et al. (2006) obtained for air of deep convective origin to as-
cent (with the help of cirrus) to the 370 K surface. We find
that the time distributions are largely insensitive to a bias of
about ±1km (∓5K) in the cloud top heights with the mean
times shifted by about ∓4 days. During the course of the revision of this work, we became
aware of independent work by Bergman et al. (2011) which
addresses similar questions and has obtained a number of re-
sults which are, to a large extent, comparable to some of the
results presented here. There are some noticeable discrep-
ancies regarding results obtained during the boreal summer
season that might be due to differences in the heating rates
(see also Wright et al. (2011) where some sensitivity to the
underlying dataset is found), which is another motivation to
further investigate this question in the future. The combination of a fluctuating A-LZH and horizontal
motion near this barrier could also explain why some sources
of convection are more successful than other equally deep-
reaching sources in transporting air into the upper TTL. We
have deduced this uneven participation using a diagnostic
that measures the localisation of the sources within the space
they occupy. Acknowledgements. The authors thank G. Berthet, M. Bolot, J.-P. Duvel, S. Fueglistaler, P. H. Haynes, T.-Y. Koh and S. Y. Liu
for useful discussions as well as three anonymous referees for
their constructive comments. The results were obtained using
ERA-Interim data, provided by the ECMWF, and the CLAUS
archive, held at the British Atmospheric Data Centre (BADC)
and produced using source data from the ISCCP that are made
available at the NASA Langley Atmospheric Sciences Data Center
(LASDC). A. Tzella acknowledges financial support from the
Marie Curie Individual fellowship HydraMitra No. 221827. Acknowledgements. The authors thank G. Berthet, M. Bolot, J.-P. Duvel, S. Fueglistaler, P. H. Haynes, T.-Y. Koh and S. Y. Liu
for useful discussions as well as three anonymous referees for
their constructive comments. Edited by: P. Haynes
The publication of this article is financed by CNRS-INSU. The publication of this article is financed by CNRS-INSU. The trajectory-based methodology that we have here em-
ployed provides a new way to quantify the sources of convec-
tion for large-scale transport into the upper TTL and lower
stratosphere. It has two main advantages over other La-
grangian models. Firstly, the use of brightness temperatures
to detect convection means that it is not necessary to resolve
the fast convective updrafts that would otherwise need to be
parameterised. Secondly, the use of radiative heating rates
to represent vertical motion out of convection means that the
descending trajectory motions associated with cloud-free re-
gions between deep convective clouds are represented. It
would be interesting to compare our results with correspond-
ing results obtained in other Lagrangian models such as the
one employed in Pisso et al. (2010) in which a convective pa-
rameterisation is taken into account and found to have a large
impact on the ozone depletion potentials for VSLS. A. Tzella and B. Legras: A Lagrangian view of transport across the TTL The results were obtained using
ERA-Interim data, provided by the ECMWF, and the CLAUS
archive, held at the British Atmospheric Data Centre (BADC)
and produced using source data from the ISCCP that are made
available at the NASA Langley Atmospheric Sciences Data Center
(LASDC). A. Tzella acknowledges financial support from the
Marie Curie Individual fellowship HydraMitra No. 221827. Conversely, the strong horizontal motion within the TTL
ensures that the majority of air of convective origin is well-
mixed within the tropical lower stratosphere (for air de-
trained within the last 15-60 days) and the extra-tropical
lower stratosphere (for air detrained more than 60 days ago). The small fraction (≈10 %) of air that has been detrained
within the last 15 days is located above regions that lie in the
neighbourhood of the convective sources. The distributions
of transit times to the lower stratosphere exhibit some sea-
sonal and regional characteristics but beyond 60 days they
all decay uniformly exponentially with time. Edited by: P. Haynes 4
Conclusions Previous considerations (Corti et al., 2005, 2006; Yang et al.,
2010) have suggested that the radiative heating from cirrus
clouds could play an important role in transporting air across
the C-LZH –a barrier for vertical transport which must be Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ 12532 A. Tzella and B. Legras: A Lagrangian view of transport across the TTL A. Tzella and B. Legras: A Lagrangian view of transport across the TTL A. Tzella and B. Legras: A Lagrangian view of transport across the TTL A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12533 lot, J., Bormann, N., Delsol, C., Dragani, R., Fuentes, M., Geer,
A. J., Haimberger, L., Healy, S. B., Hersbach, H., H´olm, E. V.,
Isaksen, L., K˚allberg, P., K¨ohler, M., Matricardi, M., McNally,
A. P., Monge-Sanz, B. M., Morcrette, J.-J., Park, B.-K., Peubey,
C., de Rosnay, P., Tavolato, C., Th´epaut, J.-N., and Vitart, F.: The
ERA-Interim reanalysis: configuration and performance of the
data assimilation system, Q. J. Roy. Meteorol. Soc., 137, 553–
597, doi:10.1002/qj.828, 2011. lot, J., Bormann, N., Delsol, C., Dragani, R., Fuentes, M., Geer,
A. J., Haimberger, L., Healy, S. B., Hersbach, H., H´olm, E. V., Highwood,
E. J. and
Hoskins,
B. J.:
The
tropical
tropopause,
Q. J. Roy. Meteorol. Soc.,
124,
1579–1604,
doi:10.1002/qj.49712454911, 1998. Isaksen, L., K˚allberg, P., K¨ohler, M., Matricardi, M., McNally,
A. P., Monge-Sanz, B. M., Morcrette, J.-J., Park, B.-K., Peubey, Hodges, K., D., Chappell, W., Robinson, G. J., and Yang, G.:
An Improved Algorithm for Generating Global Window Bright-
ness Temperatures from Multiple Satellite Infrared Imagery,
J. Atmos. Ocean. Technol., 17, 1296–1312, doi:10.1175/1520-
0426(2000)017¡1296:AIAFGG¿2.0.CO;2, 2000. C., de Rosnay, P., Tavolato, C., Th´epaut, J.-N., and Vitart, F.: The
ERA-Interim reanalysis: configuration and performance of the
data assimilation system, Q. J. Roy. Meteorol. Soc., 137, 553–
597, doi:10.1002/qj.828, 2011. Devasthale, A. and Fueglistaler, S.: A climatological perspective
of deep convection penetrating the TTL during the Indian sum-
mer monsoon from the AVHRR and MODIS instruments, At-
mos. Chem. Phys., 10, 4573–4582, doi:10.5194/acp-10-4573-
2010, 2010. Holton, J. R. and Gettelman, A.: Horizontal transport and the dehy-
dration of the stratosphere, Geophys. Res. Lett., 28, 2799–2802,
doi:10.1029/2001GL013148, 2001. Holton, J. R., Haynes, P. H., McIntyre, M. E., Douglass, A. R.,
Rood, R. B., and Pfister, L.: Stratosphere-troposphere exchange,
Rev. Geophys., 33, 403–439, doi:10.1029/95RG02097, 1995. Folkins, I., Lowenstein, M., Podolske, J. R., Oltmans, S. J., and
Proffitt, M.: A barrier to vertical mixing at 14 km in the tropics:
Evidence from ozonesondes and aircraft measurements, J. Geo-
phys. Res., 104, 22095–22102, doi:10.1029/1999JD900404,
1999. James, R., Bonazzola, M., Legras, B., Surbled, K., and Fueglistaler,
S.: Water vapor transport and dehydration above convective out-
flow during Asian monsoon, Geophys. Res. Lett., 35, L20810,
doi:10.1029/2008GL035441, 2008. Fu, Q., Hu, Y., and Yang, Q.: Identifying the top of the tropical
tropopause layer from vertical mass flux analysis and CALIPSO
lidar cloud observations, Geophys. Res. Lett., 34, L14813,
doi:10.1029/2007GL030099, 2007. A. Tzella and B. Legras: A Lagrangian view of transport across the TTL Konopka, P., Grooβ, Pl¨oger, F., and M¨uller, R.: Annual cycle of
horizontal in-mixing into the lower tropical stratosphere, J. Geo-
phys. Res., 114, D19111, doi:10.1029/2009JD011955, 2009. Fu, Y., Liu, G., Wu, G., Yu, R., Xu, Y., Wang, Y., Li, R.,
and Liu, Q.:
Tower mast of precipitation over the central
Tibetan Plateau summer, Geophys. Res. Lett., 33, L05802,
doi:10.1029/2005GL024713, 2006. Levine, J. G., Braesicke, P., Harris, N. R. P., Savage, N. H.,
and Pyle, J. A.: Pathways and timescales for troposphere-to-
stratosphere transport via the tropical tropopause layer and their
relevance for very short lived substances, J. Geophys. Res., 112,
D04308, doi:10.1029/2005JD006940, 2007. Fueglistaler, S., Wernli, H., and Peter, T.: Tropical troposphere-
to-stratosphere transport inferred from trajectory calculations,
J. Geophys. Res., 109, D03108, doi:10.1029/2003JD004069,
2004. Liu, C. and Zipser, E. J.: Global distribution of convection pene-
trating the tropical tropopause, J. Geophys. Res., 110, D23104,
doi:10.1029/2005JD006063, 2005. Liu, Y. S., Fueglistaler, S., and Haynes, P. H.: The advection-
condensation paradigm for stratospheric water vapour., J. Geo-
phys. Res., 115, D24307, doi:10.1029/2010JD014352, 2010. Fueglistaler, S., Bonazzola, M., Haynes, P. H., and Peter, T.: Strato-
spheric water vapor predicted from the Lagrangian temperature
history of air entering the stratosphere in the tropics, J. Geophys. Res., 110, D08107, doi:10.1029/2004JD005516, 2005. Martins, E., Noel, V., and Chepfer, H.: Properties of cirrus and
subvisible cirrus from nighttime Cloud-Aerosol Lidar with Or-
thogonal Polarization (CALIOP), related to atmospheric dy-
namics and water vapor, J. Geophys. Res., 116, D02208,
doi:10.1029/2010JD014519, 2011. Fueglistaler, S., Dessler, A. E., Dunkerton, T. J., Folkins, I., Fu, Q.,
and Mote, P. W.: Tropical tropopause layer, Rev. Geophys., 47,
RG1004, doi:10.1029/2008RG000267, 2009a. Fueglistaler, S., Legras, B., Beljaars, A., Morcrette, J.-J., Sim-
mons, A., Tompkins, A. M., and Uppala, S.: The diabatic heat
budget of the upper troposphere and lower/mid stratosphere in
ECMWF reanalyses, Q. J. Roy. Meteorol. Soc., 135, 21–37,
doi:10.1002/qj.361, 2009b. Massie, S., Gettelman, A., W., R., and Baumgardner, D.: Distribu-
tion of tropical cirrus in relation to convection, J. Geophys. Res.,
113, 4591, doi:10.1029/2001JD001293, 2002. Monge-Sanz, B. M., Chipperfield, M. P., Simmons, A. J., and Up-
pala, S. M.: Mean age of air and transport in a CTM: Comparison
of different ECMWF analyses, Geophys. Res. Lett., 34, L04801,
doi:10.1029/2006GL028515, 2007. Gettelman, A. and de Forster, P. M.: Definition and climatology of
the tropical tropopause layer, J. Meteorol. Soc. Jpn., 80, 911–
924, 2002. References Bergman, J. W., Jensen, E. J., Pfister, L., and Yang Q.: Seasonal dif-
ferences of vertical-transport efficiency in the tropical tropopause
layer: On the interplay between tropical deep convection, large-
scale vertical ascent, and horizontal circulations, J. Geophys. Res., submitted, 2011. Berthet, G., Esler, J. G., and Haynes, P. H.:
A Lagrangian
perspective of the tropopause and the ventilation of the
lowermost stratosphere,
J. Geophys. Res.,
112,
D18102,
doi:10.1029/2006JD008295, 2007. Bonazzola, M. and Haynes, P. H.: A trajectory-based study of
the tropical tropopause region, J. Geophys. Res., 109, D20112,
doi:10.1029/2003JD004356, 2004. The most important limitation of this work concerns the
realism of the radiative heating rates in the ERA-Interim re-
analysis dataset. As already noted, uncertainty in their values
arises mostly due the influence of clouds. Despite this uncer-
tainty, we believe that motion near the A-LZH will continue
to depend on its fluctuating structure as the accuracy in the
values of the radiative heating rates increases. Further work
will require the comparison with radiative calculations per-
formed using real distribution of clouds, as diagnosed, e.g. by CloudSat/CALIPSO (Sassen et al., 2008; Martins et al.,
2011). Corti, T., Lup, B. P., Peter, T., V¨omel, H., and Fu, Q.: Mean ra-
diative energy balance and vertical mass fluxes in the equatorial
upper troposphere and lower stratosphere, Geophys. Res. Lett.,
32, L06802, doi:10.1029/2004GL021889, 2005. Corti, T., Luo, B. P., Fu, Q., V¨omel, H., and Peter, T.: The impact
of cirrus clouds on tropical troposphere-to-stratosphere transport,
Atmos. Chem. Phys., 6, 2539–2547, doi:10.5194/acp-6-2539-
2006, 2006. Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli,
P., Kobayashi, S., Andrae, U., Balmaseda, M. A., Balsamo, G.,
Bauer, P., Bechtold, P., Beljaars, A. C. M., van de Berg, L., Bid- Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL Nawrath, S.: Water vapor in the tropical upper troposphere: On
the influence of deep convection., Ph.D. thesis, Universit¨at K¨oln,
Germany, 2002. Gettelman, A., Salby, M. L., and Sassi, F.: Distribution and influ-
ence of convection in the tropical tropopause region, J. Geophys. Res., 107, 4080, doi:10.1029/2001JD001048, 2002. Park, S., Jimnez, R., Daube, B. C., Pfister, L., Conway, T. J., Got-
tlieb, E. W., Chow, V. Y., Curran, D. J., Matross, D. M., Bright,
A., Atlas, E. L., Bui, T. P., Gao, R.-S., Twohy, C. H., and Wofsy,
S. C.: The CO2 tracer clock for the Tropical Tropopause Layer,
Atmos. Chem. Phys., 7, 3989–4000, doi:10.5194/acp-7-3989-
2007, 2007. Gettelman, A., de Forster, P. M., Fujiwara, M., Fu., Q., V¨omel,
H., Gohar, L. K., Johanson, C., and Ammerman, M.: Radiation
balance of the tropical tropopause layer, J. Geophys. Res., 109,
D07103, doi:10.1029/2003JD004190, 2004. Hatsushika, H. and Yamazaki, K.: Stratospheric drain over Indone-
sia and dehydration within the tropical tropopause layer diag-
nosed by air parcel trajectories, J. Geophys. Res., 108, D194610,
doi:10.1029/2002JD002986, 2003. Pisso, I. and Legras, B.:
Turbulent vertical diffusivity in the
sub-tropical stratosphere, Atmos. Chem. Phys., 8, 697–707,
doi:10.5194/acp-8-697-2008, 2008. Hartmann, D. L., Holton, J. R., and Fu, Q.: The heat balance of the
tropical tropopause, cirrus, and stratospheric dehydration, Geo-
phys. Res. Lett., 28, 1969–1972, doi:10.1029/2000GL012833, Pisso, I., Haynes, P. H., and Law, K. S.:
Emission loca-
tion dependent ozone depletion potentials for very short-lived Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/ A. Tzella and B. Legras: A Lagrangian view of transport across the TTL 12534 A. Tzella and B. Legras: A Lagrangian view of transport across the TTL halogenated species, Atmos. Chem. Phys., 10, 12025–12036,
doi:10.5194/acp-10-12025-2010, 2010. Stohl, A., Cooper, O. R., and James, P.:
A Cautionary Note
on the Use of Meteorological Analysis Fields for Quanti-
fying Atmospheric Mixing, J. Atmos. Sci., 61, 1446–1453,
doi:10.1175/1520-0469(2004)061<1446:ACNOTU>2.0.CO;2,
2004. Ploeger, F., Konopka, P., G¨unther, G., Grooß, J.-U., and M¨uller,
R.: Impact of the vertical velocity scheme on modeling trans-
port in the tropical tropopause layer, J. Geophys. Res., 115,
doi:10.1029/2009JD012023, 2010. Stohl, A., Forster, C., Frank, A., Seibert, P., and Wotawa,
G.: Technical note: The Lagrangian particle dispersion model
FLEXPART version 6.2, Atmos. Chem. Phys., 5, 2461–2474,
doi:10.5194/acp-5-2461-2005, 2005. Ploeger, F., Fueglistaler, S., Grooß, J.-U., G¨unther, G., Konopka, P.,
Liu, Y. A. Tzella and B. Legras: A Lagrangian view of transport across the TTL S., M¨uller, R., Ravegnani, F., Schiller, C., Ulanovski, A.,
and Riese, M.: Insight from ozone and water vapour on transport
in the tropical tropopause layer (TTL), Atmos. Chem. Phys., 11,
407–419, doi:10.5194/acp-11-407-2011, 2011. Wang, P. H., Minnis, P., McCormick, M. P., Kent, G. S., and
Skeens, K. M.: A 6-year climatology of cloud occurence fre-
quency from Stratospheric Aerosol and Gas Experiment II ob-
servations (1985- 1990), J. Geophys. Res., 101, 29407–29429,
doi:10.1029/96JD02962, 1996. Sassen, K., Wang, Z., and Liu, D.: Global distribution of cir-
rus clouds from CloudSat/Cloud-Aerosol Lidar and Infrared
Pathfinder Satellite Observations (CALIPSO) measurements,
J. Geophys. Res., 113, D00A12, doi:10.1029/2008JD009972,
2008. Winker, D. M. and Trepte, C. R.: Laminar cirrus observed near
the tropical tropopause by LITE, Geophys. Res. Lett., 25, 3351–
3354, doi:10.1029/98GL01292, 1998. Schiller, C., Grooss, J.-U., Konopka, P., Pl¨oger, F., Silva dos
Santos, F. H., and Spelten, N.: Hydration and dehydration at
the tropical tropopause, Atmos. Chem. Phys., 9, 9647–9660,
doi:10.5194/acp-9-9647-2009, 2009. WMO: Scientific Assessment of Ozone Depletion: 2006, Techni-
cal report no. 50, World Meteorological Organization, Geneva,
2007. Schoeberl, M. R., Douglass, A. R., Zhu, Z., and Pawson, S.: A
comparison of the lower stratospheric age spectra derived from
a general circulation model and two data assimilation systems,
J. Geophys. Res., 108, 4113, doi:10.1029/2002JD002652, 2003. Wohltmann, I. and Rex, M.: Improvement of vertical and resid-
ual velocities in pressure or hybrid sigma-pressure coordinates
in analysis data in the stratosphere, Atmos. Chem. Phys., 8, 265–
272, doi:10.5194/acp-8-265-2008, 2008. Wright, J. S., Fu, R., Fueglistaler, S., Liu, Y. S., and Zhang, Y.:
The influence of summertime convection over South-East Asia
on water vapor in the tropical stratosphere, J. Geophys. Res.,
doi:10.1029/2010JD015416, in press, 2011. Sherwood,
S. C. and Dessler,
A. E.:
Convective Mixing
near the Tropical Tropopause:
Insights from Seasonal Vari-
ations, J. Atmos. Sci., 60, 2674–2685, doi:10.1175/1520-
0469(2003)060¡2674:CMNTTT¿2.0.CO;2, 2003. Sherwood, S. C., Chae, J.-H., Minnis, P., and McGill, M.: Underes-
timation of deep convective cloud tops by thermal imagery, Geo-
phys. Res. Lett., 31, L11102, doi:10.1029/2004GL019699, 2004. Yang, Q., Fu, Q., and Hu, Y.: Radiative impacts of clouds in
the tropical tropopause layer, J. Geophys. Res., 115, D00H12,
doi:10.1029/2009JD012393, 2010. Stohl, A., Wernli, H., James, P., Bourqui, M., Forster, C., Lin-
iger, M. A., Seibert, P., and Sprenger, M.: A New Perspective
of Stratosphere-Troposphere Exchange, B. Am. Meteorol. Soc.,
84, 1565–1573, doi:10.1175/BAMS-84-11-1565, 2003. Atmos. Chem. Phys., 11, 12517–12534, 2011 www.atmos-chem-phys.net/11/12517/2011/
|
https://openalex.org/W3094514017
|
https://serval.unil.ch/resource/serval:BIB_3416121BA6C5.P001/REF.pdf
|
English
| null |
What Drives Online Transparency Practices at the Local Level? Evidence from 2222 Municipalities in Switzerland
|
Yearbook of Swiss administrative sciences
| 2,020
|
cc-by
| 8,783
|
YSAS Mabillard, V., & Keuffer, N. (2020). What Drives Online Transparency Practices at the
Local Level? Evidence from 2222 Municipalities in Switzerland. Swiss Yearbook of
Administrative Sciences, 11(1), pp. 158–170. DOI: https://doi.org/10.5334/ssas.143 YSAS YSAS Mabillard, V., & Keuffer, N. (2020). What Drives Online Transparency Practices at the
Local Level? Evidence from 2222 Municipalities in Switzerland. Swiss Yearbook of
Administrative Sciences, 11(1), pp. 158–170. DOI: https://doi.org/10.5334/ssas.143 1. Introduction Depicted by Heald (2012: 31) as a “public virtue, which it is discreditable or inadvisable to oppose,”
transparency is still considered as an essential pillar of good governance. Praised for its power to reveal
hidden secrets, corrupt practices or dysfunction, it is growingly used by public organizations as a guideline
in their operations. It is also frequently promoted for its supposed beneficial effects on the efficiency of
administrations, citizen trust and participation, and accountability from public bodies towards the public at
large (Esty 2006). These factors have led to the global development of transparency, especially through the
explosion of Freedom of Information (FOI) laws, which allow citizens to request official information from
public bodies. These laws are expected to solve accountability problems within democratic systems, where
governments “often act without informing the public and, for the most part, are not subject to sanctions for
wrongdoing” (Ackerman & Sandoval-Ballesteros 2006: 86). g
g (
)
Increased transparency is usually regarded as a way to rebalance the relationship between the governed
and those who govern. This relationship particularly matters at the local level, where people generally show
more interest in policies that have an impact on their lives: interactions tend to be more frequent, since
services delivered at the local level directly affect citizens. Public organizations can therefore better respond
to the requests expressed by the population. Yet the responsiveness of public authorities and the quality of
interactions between them and citizens depend on transparency practices (Welch et al. 2005). This article focuses on the proactive release of information. Recently, technological evolutions have
oriented contributions on the matter towards online disclosure of information. Meijer (2009) states that
the development and adoption of the internet by public administrations have changed the relationship
with the governed, giving them more timely information via computer-mediated transparency. This
perspective is adopted in this study since governments are increasingly communicating via online channels. Transparency is therefore understood as the voluntary dissemination of information by municipalities on
their website. It is essential to inform citizens about the characteristics, internal workings or performance of
public organizations. This perspective differs from the passive form of transparency, which relies on specific
requests sent to public bodies by citizens, usually in the framework of a dedicated legislation. Switzerland provides an interesting case study to explore government transparency. 1. Introduction Although it belongs
to the most advanced nations in terms of technology penetration among households according to the
International Telecommunication Union (ITU 2017) and ranks first regarding internet for business usage,
technology adoption differs significantly between the private and the public sector. The country still relies
on an administrative culture of secrecy, despite the ideological shift provoked by the implementation of the
FOI law in 2006 (Cottier 2014). Moreover, several cantons do not yet have legislation on transparency. (
)
,
y
g
p
y
Although some contributions have tried to identify the determinants of online transparency at the local
level (e.g. de Araujo & Tejedo-Romero 2016), no attempt has so far been made to provide an exhaustive,
nation-wide analysis. Our study covers all 2222 municipalities of Switzerland (as of 1 January 2018) through
a self-created index of information disclosed on the municipalities’ websites. This extensive effort helps to
respond to the first research question (RQ1) addressed here: how transparent are Swiss municipalities in
their online communication? Our study also considers variables used in previous research and specifically
concentrates on dimensions relevant in the Swiss context. The second research question (RQ2) takes a
more explanatory perspective and focuses on variables directly related to transparent practices. From this
point of view, what can explain higher levels of transparency in Swiss municipalities’ online communication? The article is structured as follows. The first part focuses on theoretical grounds for explaining the success
of transparency and for studying the concept in the public sector. In the second part, the Swiss context is
developed, including the passing of the FOI law. The construction of the online transparency index is also
presented. The third part concentrates on the methodology used to develop our analysis model and the
related hypotheses. The fourth part provides readers with more detailed information about the results of
our study, referring more specifically to the answers given to the hypotheses. Finally, these results are further
discussed in the concluding part. Although some contributions have tried to identify the determinants of online transparency at the local
level (e.g. de Araujo & Tejedo-Romero 2016), no attempt has so far been made to provide an exhaustive,
nation-wide analysis. Our study covers all 2222 municipalities of Switzerland (as of 1 January 2018) through
a self-created index of information disclosed on the municipalities’ websites. 1. Introduction This extensive effort helps to
respond to the first research question (RQ1) addressed here: how transparent are Swiss municipalities in
their online communication? Our study also considers variables used in previous research and specifically
concentrates on dimensions relevant in the Swiss context. The second research question (RQ2) takes a
more explanatory perspective and focuses on variables directly related to transparent practices. From this
point of view, what can explain higher levels of transparency in Swiss municipalities’ online communication? h
i l i
d
f ll
h fi
f
h
i
l
d f
l i i
h The article is structured as follows. The first part focuses on theoretical grounds for explaining the success
of transparency and for studying the concept in the public sector. In the second part, the Swiss context is
developed, including the passing of the FOI law. The construction of the online transparency index is also
presented. The third part concentrates on the methodology used to develop our analysis model and the
related hypotheses. The fourth part provides readers with more detailed information about the results of
our study, referring more specifically to the answers given to the hypotheses. Finally, these results are further
discussed in the concluding part. RESEARCH
What Drives Online Transparency Practices at the
Local Level? Evidence from 2222 Municipalities in
Switzerland Vincent Mabillard1 and Nicolas Keuffer2 1 Université Libre de Bruxelles, BE 2 Université de Lausanne, CH Corresponding author: Vincent Mabillard (vincent.mabillard@ulb.be) Regarded as a core principle of good governance, transparent government communication has
been discussed at the national level in particular. This article aims to extend this reflection
by assessing the transparency practices of all Swiss municipalities in 2018, using an index
of the volume of information published online (LTI). The results show that the practices of
municipalities are very heterogeneous and that the population size and financial capacity of
municipalities have a significant impact on the amount of information disseminated on their
official websites. Keywords: Online transparency; local government; information disclosure; digital state;
Switzerland En tant que principe fondamental de bonne gouvernance, la communication de l’État a été
examinée principalement au niveau national. Cet article vise à étendre cette réflexion en
évaluant les pratiques de transparence de toutes les municipalités suisses en 2018, à l›aide d›un
indice déterminant le niveau d’informations publié en ligne (LTI). Les résultats montrent que les
pratiques des municipalités sont très hétérogènes et que la taille de la population et la capacité
financière des municipalités ont un impact significatif sur la quantité d›informations diffusées
sur leurs sites web. Mots-clés: Transparence en ligne; gouvernement local; mise à disposition d’information; État
digital; Suisse Als Kernprinzip guter Regierungsführung wurde die Kommunikation des Staates vor allem auf
nationaler Ebene untersucht. Dieser Artikel will diese Überlegungen erweitern, indem er, anhand
eines Index den Grad ihrer Offenlegung online (LTI), die Transparenzpraktiken aller Schweizer
Gemeinden im Jahr 2018 evaluiert. Die Ergebnisse zeigen, dass die Praktiken zwischen den
Gemeinden sehr heterogen sind und dass die Bevölkerungszahl und die finanzielle Kapazität
der Gemeinden einen erheblichen Einfluss auf den Umfang der auf ihren Websites verbreiteten
Informationen haben. Stichwörter: Online-Transparenz; Kommunalverwaltung; Offenlegung von Informationen;
Digitaler Staat; Schweiz Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 159 Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 2. Theoretical underpinnings p
g
Bouckaert and Pollitt (2011: 111) argue that “interestingly, transparency is not something which seems to
fit neatly into some of the groupings which we have found important for other aspects of reform. Thus,
we cannot say, for example, that the core NPM states were way ahead (or behind) in the transparency
stakes”. This observation extends to the issue of adoption: why do governments favor transparency and
pass freedom of information laws threatening their power (Worthy 2017)? Research has remained rather
exploratory so far, presenting scattered evidence related to the determinants leading governments to act Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 160 in a more transparent way. From a theoretical perspective, Erkkilä (2012: 129) insists on the paths taken by
jurisdictions towards transparency, saying that path dependencies can help “understand why reforms tend
to take differing institutional forms in national contexts”. Particular circumstances related to a given context
can also individually explain why the idea of transparency reaches the top of the political agenda at a certain
point in time. All in all, it became an increasingly popular concept due to its expected contribution to better
governance. Indeed, the strong instrumental value conferred to transparency attributed a central role to
the notion and raised high expectations regarding its ability to increase citizen participation and trust in
government (Mabillard & Pasquier 2016). The literature on transparency shows that the multifaceted character of the concept poses a major
challenge to clearly defining its boundaries (Pasquier 2013). Meijer et al. (2012) distinguish between
two dimensions of open government: participation and transparency, which is understood as access to
government information, both intentional and through whistle-blowing acts. Here, we focus on intentional
access to official information, especially the proactive release of information by public authorities). For
clarification purposes, differences between transparency types are summarized below (see Table 1). According to Pasquier (2013), proactive disclosure is the less codified form of transparency, although it
has been a concern at the local level since the 1970s. An international treaty is under way and guidelines
do exist regarding environmental information, but focuses mainly on the member states’ requirements to
respond to requests sent by citizens. 1 The ratification by the Ukrainian Parliament was communicated by the Council of Europe in May 2020 (https://www.coe.int/en/
web/kyiv/-/ukraine-has-ratified-the-council-of-europe-convention-on-access-to-official-documents). Switzerland has not signed
the Convention, showing its cautious approach to transparency. 2. Theoretical underpinnings Following a recommendation made in 1981 at the Council of Europe
(COE) regarding access to administrative documents, a Convention was created in 2009 in Tromsø, Norway. A vast majority of COE members has not signed the Convention, indicating that transparency remains a
disputed issue and that many countries prefer to adopt a conservative posture when it comes to government
openness. Nevertheless, Ukraine became the tenth country to ratify the Convention in May 2020, which
launched this international document, since ten ratifications were needed to the enforcement of the
Convention. As a result, a Group of Specialists will be established to monitor the implementation provisions
of the Convention by the signatory states.1 Studies focusing on passive transparency have bloomed recently, resulting from the explosion of FOI laws
across the globe. These laws provide “the public [with] a legally guaranteed right of access to information
held by the government, the main objective being to force public authorities to disclose what they would
rather keep secret” (Pasquier & Villeneuve, 2007: 149). While requests submitted to government bodies can
be complementary to the proactive release of information, they remain a distinctive feature of transparency
due to the constraint character of the documents disclosed. Although a majority of jurisdictions now have
legislation on transparency, some refrain from granting access to information rights, also at the subnational
level. Despite the recent development of research on passive transparency, issues related to technology focus
on proactive disclosure of information online. In this sense, Meijer (2009) claims that computer-mediated
transparency is often regarded as improving governance, based on the idea that “computer-mediated Table 1: Main types of transparency. Table 1: Main types of transparency. Table 1: Main types of transparency. Definition
Characteristics
Active
Proactive release of information on a voluntary basis,
increasingly through online platforms (especially on
government websites and apps)
Less codified form of transparency (Pasquier
2013), but increasingly used following the
development of information and communication
technologies (ICTs)
Passive
Disclosure of information on a constrained basis (as a
response to official FOI requests or non-FOI requests)
Most codified form of transparency when a
legislation on the matter exists (FOI). 2. Theoretical underpinnings Laws’
features differ strongly from one case to another
(Worthy 2017)
Forced
Spontaneous, uncontrolled disclosure of information
by internal or external stakeholders, triggering quick
reactions from governments
Processes surrounding whistleblowing phenomena
are not always codified but protection regimes are
being reinforced (Council of the EU 2019) Less codified form of transparency (Pasquier
2013), but increasingly used following the
development of information and communication
technologies (ICTs) Passive
Disclosure of information on a constrained basis (as a
response to official FOI requests or non-FOI requests) Passive
Disclosure of information on a constrained basis (as a
response to official FOI requests or non-FOI requests) Forced
Spontaneous, uncontrolled disclosure of information
by internal or external stakeholders, triggering quick
reactions from governments Forced
Spontaneous, uncontrolled disclosure of information
by internal or external stakeholders, triggering quick
reactions from governments Processes surrounding whistleblowing phenomena
are not always codified but protection regimes are
being reinforced (Council of the EU 2019) 1 The ratification by the Ukrainian Parliament was communicated by the Council of Europe in May 2020 (https://www.coe.int/en/
web/kyiv/-/ukraine-has-ratified-the-council-of-europe-convention-on-access-to-official-documents). Switzerland has not signed
the Convention, showing its cautious approach to transparency. Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 161 Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland transparency gives people better information and thus contributes to the rationalization of society” (Meijer
2009: 257). As a result, information published on websites continues to grow, and a significant amount
of recent studies on transparency have focused on proactive dissemination of information online, often
using it as the main dependent variable (da Cruz et al. 2016). This approach is preferred here, as websites of
Swiss municipalities have been coded into an index used to create the dependent variable of our analytical
framework. From an empirical point of view, the review of the literature shows that most contributions have focused
on a large number of variables, thereby trying to determine which factors can explain the dissemination
online of information by public authorities. These variables can be gathered in specific categories: socio-
demographic (e.g. population size), financial (e.g. municipal taxes), institutional and political (e.g. government characteristics) or organizational (e.g. size of government) (Albalate del Sol 2013; Caamaño-
Alegre et al. 2013; Tejedo-Romero & de Araujo 2018). 2 152.3 Federal Act of 17 December 2004 on Freedom of Information in the Administration (Freedom of Information Act, LTrans).
3 Data were retrieved manually from all websites in the span of three months in 2018, using a codebook. Link to the dataset: https://
www.researchgate.net/publication/341370817_Local_Transparency_Index_CH_Final. 3. Transparency in the Swiss context: transparency index, determinants
and hypotheses yp
In Switzerland, the implementation of the Federal Act on Freedom of Information in the Administration
(LTrans)2 in 2006 changed the way administrations work, since all documents – except for exemptions
specifically set in the legislation – can be requested by citizens. Worthy (2017) explains that FOI emerges as
a result of institutional reforms, the strong symbolism of openness making FOI hard to resist and hard to
escape for jurisdictions that have adopted it. In Switzerland, transparency gained popularity through early
working groups, which planned the draft of an FOI law. At the subnational level, cantons remain autonomous
and do not depend on the LTrans; some of them have not adopted any legislation on transparency, arguing
that the system functions well in their jurisdiction as things stand. 2. Theoretical underpinnings It should be noted that a majority of these studies’
statistical models have been applied to the specific cases of Portugal and Spain. For this reason, variables
and indicators used in this particular context have been reframed and relevantly selected according to the
peculiarities of the Swiss case. 3.1 The local transparency index (LTI) Although details about the LTrans have been extensively discussed at the national level (Pasquier 2013),
contributions about proactive disclosure remain almost non-existent. Here, we take a global perspective
on active transparency online to deal with RQ1: how transparent is the online communication of Swiss
municipalities? This is addressed through the creation of the local transparency index (LTI), which was built
by collecting data on all Swiss municipalities’ websites.3 It consists of six dimensions based on the index
used by da Cruz et al. (2016). The process consisted in the elimination of indicators that do not apply at
the municipal level in the Swiss case through a random selection of municipal websites (e.g. information
communicated by other levels of government). All dimensions include a set of indicators (Table 2), which have been coded 1 (information can be found
on the website) or 0, allowing us to compile scores (non-weighted means) and draw up a ranking for all
municipalities in Switzerland (N = 2222). Since active transparency remains the focus of the present article,
the LTI is used here as the dependent variable. 3.2 Determinants of local government transparency and research hypotheses
The determinants of transparency are presented together with corresponding hypotheses. This empirical
strategy, in line with a previous study on transparency at the local level (Tejedo-Romero & de Araujo 2018)
allows us to develop a series of independent variables integrated into our statistical model. The multivariate
analysis (ordinary least squares regression – OLS) integrates cluster standard errors (CSE) to overcome the
problem of having variables at different levels (cantonal and municipal). Indeed, the existence of a FOI law
is cantonal and applies equally to all municipalities in a given canton, while other variables are situated
at the municipal level. This will enable us to respond more precisely to RQ2, which aims to pinpoint
what factors explain a higher level of proactive online transparency in certain municipalities compared
to others. 162 Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland Table 2: Dimensions and indicators of the local transparency index (LTI). Dimensions
Indicators
A. Organizational
information, social
composition and operation
of the municipality
1. General information on the role and functions of the executive body (distribution
of the departments or dicastères)
2. Roles and functions of the legislative commissions
3. Biographical note/CV of the members of the executive council
4. 3.2.1 Population size Although the elected representatives of small municipalities may show better responsiveness to citizens’
demands, studies that empirically tested the factors leading to greater dissemination of information
found a positive and statistically significant impact of size, because of the increased resources available
to larger municipalities and the greater number of activities that need to be communicated (de Araujo &
Tejedo-Romero 2016). Since the Swiss municipal structure is highly fragmented,4 with population as well
as resources and tasks performed varying considerably, the number of inhabitants in a municipality (FSO,
2018a) is tested here. Hypothesis 1: Larger municipalities are more likely to proactively disseminate information on
their website. 3.1 The local transparency index (LTI) Possibility of direct contact with members of the executive council (email or/and
phone)
5. Register of interests of members of the executive council
6. Agenda/minutes of the municipal legislative sessions in the last 2 years (either
one or the other)
B. Reports and planning
1. Annual activity report (already done)
2. Strategic plan (undertaking)
3. Public works in progress (underway)
C. Local taxes, rates and
regulations
1. Information on the tax rate
2. Information on municipal taxes
3. Regulations
4. Publication of a newsletter or an information journal
D. Relations with citizens as
customers
1. Search engine on the website of the municipality
2. Links to social networks
3. Possibility of submitting a request online
4. Information on opening hours (municipality)
E. Public procurement
1. Tenders for public contracts
F. Economic and financial
transparency
1. Publication of the annual budget
2. Publication of municipal accounts Table 2: Dimensions and indicators of the local transparency index (LTI). 4 As of 1 January 2018, the population of the 2222 Swiss municipalities varies considerably, the average of all municipalities’ popula
tion size being 3818 and the median 1507 inhabitants (FSO 2018a).
5 Question 38: “In general, what is the degree of autonomy of your municipality in your opinion?” (1 = no autonomy; 10 = far-
reaching autonomy). 5 Question 38: “In general, what is the degree of autonomy of your municipality in your opinion?” (1 = no autonomy; 10 = f
reaching autonomy). 4 As of 1 January 2018, the population of the 2222 Swiss municipalities varies considerably, the average of all municipalities’ popu
tion size being 3818 and the median 1507 inhabitants (FSO 2018a). 6 This survey was sent to the secretaries of all 2255 Swiss municipalities in 2017 (response rate = 82.8%) (ZHAW & IDHEAP 2017).
7 We obtained the data by entering manually the 2221 municipalities on comparis.ch. No data for Basel-City since municipal and
cantonal taxes overlap. Hypothesis 2: More autonomous municipalities are more likely to proactively disseminate infor
mation on their website. Hypothesis 2: More autonomous municipalities are more likely to proactively disseminate infor
mation on their website. 3.2.5 Existence of an access to information law In other federalist countries such as the USA or Canada, all states/provinces have enacted an FOI law, but
only 19 Swiss cantons out of 26 have implemented such legislation (applicable at the municipal level). We
argue that municipalities located in a canton where transparency is supported through an FOI law may
be more transparent in their online communication with citizens. To this end, we have created a dummy
variable expressing whether a municipality is situated in a canton where a law on information exists or
not. Darbishire (2010) has shown that FOI laws, increasingly incorporating guidelines for more proactive
transparency, are expected to stimulate the voluntary release of information by local authorities. In
Switzerland, guides of good practices are distributed to the municipalities when FOI laws exist, highlighting
the need for them to communicate voluntarily their actions. Hypothesis 5: Municipalities located in a canton where a law on access to information exists are
more likely to proactively disseminate information on their website. 3.2.3 Political culture Reforms guided by the New Public Management (NPM) ideas of transforming the internal organizational
structure, the steering instruments and the processes of delivering services to citizens represents the most
widespread changes in Swiss municipalities (Kersting & Vetter 2003). The NPM movement has strengthened
transparency to bring citizens closer to the authorities and change the bureaucratic model into a customer-
friendly service enterprise. However, empirical evidence shows that it has spread unevenly across the country
because there are important cultural differences between the language areas when it comes to the role of
the state and of municipalities, with the Latin part being more resistant to reforms challenging the state as
the unique provider of public services (Ladner 2016). Hypothesis 3: French- and Italian-speaking municipalities are less likely to proactively disseminate
information on their website. 3.2.4 Political participation As far as political variables are concerned, the literature examined very often includes voter turnout,
expressed as the percentage of participation in the last municipal elections (Albalate del Sol 2013; Tejedo-
Romero & de Araujo 2018). In Switzerland, we concentrate on the turnout in the last elections of the
municipal executive, based on data collected in a recent survey on Swiss municipalities,6 and take into
account the close relationship between citizens and the authorities. Consequently, a greater interest in local
politics expressed through electoral turnout may encourage the authorities to give more information on
plans, budgets and activities. Hypothesis 4: The higher the turnout in the elections of the municipal executive, the larger the
volume of information proactively disseminated by these municipalities on their website. 3.2.2 Municipal autonomy According to the theoretical model developed by Schmidt (2013), transparency is expected to increase the
legitimacy of public authorities. Transposed to the local level in Switzerland, this approach has been used
to test the relation between the level of autonomy and transparency at the local level (Keuffer & Mabillard
2019). It revealed a significant relationship between transparency and autonomy when the latter was used
as the main independent variable. Municipal autonomy was considered as a complex relational construct in
which municipalities “reflect and develop a sense of place through political and social interaction” (Pratchett
2004: 366). Subsequently, the realization of formally granted municipal autonomy through political
activities was apprehended through the perceptions of executive bodies’ members (ZHAW & IDHEAP 2018).5
Taking into account the influence of local factors, municipal autonomy is also regarded here as a bottom-up Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 163 phenomenon, and we assume that online dissemination of information will be more intensive in more
autonomous municipalities. 3.2.6 Municipal taxes This variable is retrieved from a contribution by Caamaño-Alegre et al. (2013), who expect a positive
association between per-capita municipal taxes and government transparency. When citizens pay higher
taxes, they are supposedly entitled to demand more information, and the municipality has more resources
to provide the population with higher levels of information. We obtained the effective cost of taxes in every
Swiss municipality (for a married couple without children who earn a median annual salary of CHF 6502;
FSO 2016) by using a comparative website, this variable being unavailable in official public records.7 Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 164 Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland Hypothesis 6: The higher the municipal taxes, the greater the volume of information proactively
disseminated by these municipalities on their website. Hypothesis 6: The higher the municipal taxes, the greater the volume of information proactively
disseminated by these municipalities on their website. 3.2.7 Municipal workforce Another variable related to resources available for communication concerns the staff working in a
municipality’s administration to deliver public services. We have created a proxy for administrative capacity
by considering the total amount of full-time positions for each municipality (FSO 2018b). According to
Fairbanks et al. (2007: 32): “when agencies and communicators consider opening up agency processes they
have to balance the impact that committing more resources in one area will have on another area”. In this
vein, we expect that municipalities with more staffing resources will communicate more transparently. Hypothesis 7: The larger the municipal workforce, the greater the volume of information proac
tively disseminated by municipalities on their website. 3.2.8 Median age Age was found to have an inverse relationship with higher levels of transparency, especially when considering
elderly vs. young people in municipalities (Bernick et al. 2014). In Switzerland, older individuals tend to
vote more and to be generally more active politically (Adler 2016). In this sense, we expect municipalities
with a higher percentage of elderly people to be more transparent on their activities, since the demand for
information may be higher in such municipalities. Here, we have created a more precise variable to test this
relationship by using the median age for all municipalities (based on FSO 2018a). Hypothesis 8: The higher the median age in a municipality, the larger the volume of information
proactively disseminated by the municipality on its website. Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 165 The results show great diversity among the different indicators. The online communication of Swiss
municipalities is on average weak (below 17%) regarding the functions of legislative commissions,
biographical notes and the register of interests of members of the executive council and annual activity
reports. Low scores are also observed in the cases of annual activity reports for example. By contrast, it
is very frequent (the mean is above 79%) for Swiss municipalities to disseminate information about the
responsibilities assumed by the executive body, regulations, and a search engine is almost always available on
their website. The country map (Figure 1) below shows the overall results for all municipalities, according to
four classes. These classes correspond to quartiles, meaning that all data have been sorted in four categories,
each containing the same number of observations. Apart from the differences between municipalities, it is
interesting to note that only a quarter of them score above 0.51 on an index that ranges from 0 to 1. The results displayed on Figure 1 show the vast diversity of Swiss municipalities, both in terms of
characteristics and transparency practices. These differences are mainly related to size and geography,
since large municipalities and urban areas tend to be more transparent. This result can be interpreted in
the light of several elements, starting with the resources (human, technical and financial) at their disposal
and the fact that more people need to be informed, and through a more “distant” relationship compared
to small municipalities, where direct contacts may be more frequent between local authorities and their
citizens. However, it remains to be seen what factors can explain these differences, taking into account other
explanatory variables commonly found in the literature. This will be done in the next section through a
multivariate analysis of the LTI and the determinants of transparency in Switzerland. 4.1 Transparency practices in Swiss municipalities’ online communication
Thi
ti
th fi t
h
ti
th
ti
t
ti
f S i
i 4.1 Transparency practices in Swiss municipalities online communication
This section answers the first research question on the active transparency practices of Swiss municipalities
by presenting the results of our self-created index of online transparency (See in Table 3 below). The LTI
potential range goes from 0 to 1 but only one municipality reaches the effective maximum of 0.97 (mean =
0.41; standard deviation = 0.15). Of the municipalities that score the minimum of 0, about 20 did not have
their own website in 2018. Since these are small municipalities located in mountainous valleys important
formal information is provided by the region where they are located. Regarding the distribution of the LTI,
no problem of skewness (–0.251) or of kurtosis (–0.032) has to be underlined and 50% of municipalities
have a score between 0.31 and 0.51 (median = 0.43). Table 3: Descriptive statistics. Table 3: Descriptive statistics. Table 3: Descriptive statistics. N
Minimum
Maximum
Mean
St. Deviation
LTI, own elaboration (municipal websites)
2222
0.000
0.972
0.411
0.146
Population size (2017), natural logarithm
2217
2.565
12.877
7.333
1.257
Perceived municipal autonomy (2017), 10 = far-reaching
autonomy
2105
1
10
6.284
1.298
Language area (2018), 1=German-speaking municipality
2212
0
1
0.643
0.479
Turnout in the elections of the municipal executive
(2017), %
1455
3
95
46.572
16.778
Existence of a cantonal FOI law (2018), 1 = yes
(own calculation)
2222
0
1
0.905
0.293
Municipal tax (2018) for standard profile, own calculation
based on comparator website
2221
1767
12278
7175.045
1573.073
Municipal full-time equivalent posts (2015), own
calculation based on FSO (2018b)
2167
0.020
11298
42.073
291.456
Median age (2017), own calculation based on FSO (2018a)
2218
31
80
45.613
3.941 Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 4.2 The determinants of transparency at the municipal level 4.2 The determinants of transparency at the municipal level
Our findings are based on a multivariate analysis (OLS), taking the LTI as the dependent variable and the
predictors presented above as the main determinants of transparency (independent variables). From a
statistical point of view, the R2 value explains 34.9% of the total variance (Table 4). No collinearity problem
has been observed here, with a minimum value of -0.507 and a maximum value of 0.621. Furthermore, the
variance-inflation factors (VIF) were also tested to analyze multicollinearity. Their values (min. 1.031; max. 2.025) are all lower than 5, thereby indicating the absence of multicollinearity in our model. The most striking result is the importance of the municipality size. In line with most previous contributions
on the subject (i.e. Albalate del Sol 2013; de Araujo & Tejedo-Romero 2016), it is strongly significant. Figure 1: Local transparency index (LTI) in 2222 Swiss municipalities regrouped in four classes. Notes: N = 2222. Four classes, 0.00 = the least transparent, 0.97 = the most transparent. Figure 1: Local transparency index (LTI) in 2222 Swiss municipalities regrouped in four classes. Notes: N = 2222. Four classes, 0.00 = the least transparent, 0.97 = the most transparent. Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 166 Table 4: Determinants of Swiss municipalities’ online communication (standardized beta coeffi
clustered standard errors). Predictors
OLS
CSE
Ln population size (2017)
0.070***
0.003
Perceived municipal autonomy (2017)
0.002
0.002
Language area (2018)
0.001
0.009
Turnout in the elections of the municipal executive (2017)
0.000
0.000
Existence of a cantonal FOI law (2018)
–0.040**
0.013
Municipal tax (2018)
0.005*
0.002
Municipal full-time equivalent posts (2015)
6.293E-6
1.722E-5
Median age (2017)
0.002*
0.001
Constant
–0.232***
0.060
R2
0.349
*** p < 0.01, ** p < 0.05, * p < 0.1. Table 4: Determinants of Swiss municipalities’ online communication (standardized beta coefficients and
clustered standard errors). *** p < 0.01, ** p < 0.05, * p < 0.1. Consequently, H1 can be confirmed since larger municipalities are more likely to proactively disseminate
information on their website. The main interpretation that can be drawn from this result is related to the
greater resources available in larger municipalities. This was already raised by Gallego-Álvarez et al. (2010),
who argued that administrative and financial capacity could affect the development of e-government,
including municipalities’ websites. 4.2 The determinants of transparency at the municipal level Moreover, the targeted population is also larger, which makes it even
more important to disseminate more information online. Finally, the greater distance between municipal
authorities and their population prevents a more direct relationship, more frequently found in smaller
municipalities. p
This result remains especially interesting in the Swiss case in the absence of a metropolis and a rather
fragmented institutional and geographical reality. This fragmentation can also explain why the other
institutional and cultural predictors presented in our analysis model are not significant. As a result, we
reject the corresponding hypotheses regarding autonomy and political culture (H2 and H3). Although
local autonomy is formalized (to different degrees) at the cantonal level, the activities and actions of Swiss
municipalities are very diverse even within the same canton, reflecting the great demographic, socioeconomic
and financial diversity that characterizes the Swiss municipal level (Keuffer & Horber-Papazian 2019). These
peculiarities of the Swiss case contrast with other contexts, for example Portugal, where financial autonomy
is an important driver of transparency (Tavares & da Cruz 2020). However, the difference between the sample
size and the construction of the variable calls for a deeper investigation when comparing the two results. Regarding political culture, our results corroborate the assessment from Bouckaert and Pollitt (2011), who
argued that more advanced NPM states were not systematically ahead in terms of government openness,
although performance management and competition principles are often associated with increased
transparency. Our results add evidence to the missing link between NPM reforms and transparency, a
reflection that extends to Web 2.0 and social media tools in recent studies (e.g. Bonsón et al. 2012). Moreover, it was expected that higher participation from citizens in municipal elections would trigger
stronger demands for transparency, based on the idea that high levels of engagement and political interest
would spark the demand for increased transparency (Piotrowski & van Ryzin, 2007). However, this variable is
not significant in our model, leading us to reject H4; this is unsurprising in Switzerland, due to the low levels
of participation at the local level (48% in 2017) in European comparison (Steiner at al. 2020). Interestingly, one of the most significant and strongest predictors in our model relates to the FOI law. Almost always neglected in previous studies on proactive dissemination of information online, the passive
form of transparency plays a role, in a rather unexpected way. 5. Conclusion and discussion This article aimed at answering two research questions. The first question addressed the proactive
dissemination of information by Swiss municipalities on their website, based on a self-created index of
local transparency covering all 2222 Swiss municipalities. Findings show that Switzerland is characterized
by strong diversity regarding transparency practices, reflecting the institutional fragmentation at the local
level. Low scores on the LTI can be explained by the absence of detailed information on the executive
councils’ members and their potential conflict of interests with external stakeholders. In addition,
communication about annual activity reports is often missing. The scores are counterbalanced by a more
frequent dissemination of information about the responsibilities assumed by the executive body and the
municipal regulatory framework. It would be interesting to further investigate the main characteristics of
online transparency in other settings to see if these are Swiss specificities or more general trends. The second question focused on variables expected to influence transparent practices. The results underline
the importance of four explaining factors, two of them playing a central role and being highly significant. Firstly, smaller municipalities are less likely to disseminate a higher volume of information online because
of the greater proximity and the potentially more direct relationship with the citizens. Moreover, in larger
municipalities, the greater number of activities and the larger population lead to a higher level of online
transparency. Secondly, findings indicate that municipalities situated in cantons where no such law exists score higher
in terms of transparency. This can be interpreted through the concept of path dependency, which highlights
the absence of the need to pass a law when the situation is perceived as satisfactory. It should be added that
transparency reforms in Switzerland are mostly supply-driven, following a global trend (Meilland 2013),
thereby reinforcing this scenario. This is particularly interesting since it sheds new light on the relationship
between active and passive transparency. Finally, two other determinants also influence online transparency practices. Financial capacity of
municipalities has a limited effect on online communication. It would be especially interesting to further
investigate whether these financial means translate into better technical infrastructure and capacity and/or
respond to demanding citizens who pay high municipal taxes. Moreover, median age also plays a minor
yet significant role on municipal online communication. This contradicts empirical evidence recorded in
previous studies (e.g. 4.2 The determinants of transparency at the municipal level In cantons which have adopted legislation on
the public’s access to official information, municipalities tend to be less transparent than their counterparts
in cantons where such legislation has not yet been passed. Consequently, we reject our hypothesis on the
effect of passive transparency on proactive dissemination of information online (H5). This observation can
be interpreted through the prism of adoption: indeed, transparency laws have sometimes been enacted in
cantons where political scandals raised awareness. On the contrary, we may deduce that in cantons without Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 167 legislation, the situation remains more satisfactory, leading to higher levels of proactive dissemination of
official information on the municipalities’ websites. In addition, our results indicate that the amount of taxes collected by the municipalities does stimulate
more information disclosure on a voluntary basis, thereby confirming H6. This contradicts what has been
previously observed empirically in other settings (e.g. in Spain: Caamaño-Alegre et al. 2013; Tejedo-Romero &
de Araujo 2018). This should however be nuanced since the coefficient is quite low and not highly significant. Besides, online transparency indexes are built differently, including diverse types of information (financial
transparency for instance): this calls for cautiousness when comparing these studies. The staffing capacity
does not play a significant role in Switzerland (H7 invalidated). This is surprising since this variable was
expected to influence online transparency practices, as it has been previously shown that government size
had a significant effect on the development of more open governments (Grimmelikhuijsen & Feeney, 2017). This is not the case in Switzerland, where governments with less staffing capacity in larger municipalities
are more proactive. p
Finally, age also plays a role in the dissemination of information by municipalities. Although socio-
demographic variables do not belong among the main determinants of transparency according to the
literature, this finding is in line with previous results observed in other contexts. Indeed, in the U.S., Piotrowski
and van Ryzin (2007) show that older persons are more likely to demand greater transparency. Older people
are more active politically in Switzerland (Adler 2016) and, although they are less likely to use the internet,
municipalities with a higher percentage of elderly people tend to disseminate more information on their
website, thereby confirming H8. 5. Conclusion and discussion Tavares & da Cruz 2020), in which municipalities with an ageing population tend to
communicate less on their website. It would be particularly interesting to dig deeper into this issue, since
younger generations (at least in Switzerland) are less interested in politics (Adler 2016) but use websites
more frequently. This may lead to a paradoxical situation in which municipalities should communicate
online more frequently to reach younger people but at the same time must be reactive towards older people,
who are more demanding in terms of local transparency. This study meets with some limitations. The first
refers to the static approach preferred here. Although inevitable at this stage, it should nevertheless be Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 168 noted that our study does not take the evolution of websites and mergers of municipalities into account. Moreover, only online communication has been taken into account as an indicator of active transparency. We acknowledge that other channels may be preferred by municipalities to connect with their citizens. In
this sense, an exploratory study from Keuffer and Mabillard (2019) with executive councilors revealed that
other channels such as direct relationships with citizens are sometimes favored in small municipalities. This
should be further explored, although feasibility remains a concern in Switzerland, where the number of
municipalities is high. p
g
A second limitation concerns the construction of the LTI. The added value of using an index lies in the
simplification of information related to the multi-faceted concept of transparency. However, it does not
allow for differences in municipal practices among the dimensions: these were selected and constructed
taking the particularities of the Swiss context into account. The disadvantage of such an adaptation is that
our measure is not systematically comparable with other countries. However, we are convinced that the LTI
is a precious informational resource and that the provision of the dataset will lead to further investigation
in Switzerland and beyond. A final limitation refers to the determinants of transparency selected here. The alignment of predictors
with previous studies would have enhanced the external validity of the paper and enabled a more systematic
comparison. Competing Interests Competing Interests The authors have no competing interests to declare. 5. Conclusion and discussion However, tests of several variables have shown that some are not amplifying the explaining
power of the analysis model (especially political variables). More importantly, several variables are unavailable
for all Swiss municipalities, mainly due to local specificities (e.g. elected councilors with no party affiliation)
and because of the lack of harmonization between accounting systems (most financial variables). Keeping these shortcomings in mind, our findings lead to several interesting paths for further research. For
instance, it would be relevant to extend the measure of municipal transparency practices in a longitudinal
perspective in order to better grasp their development over time. It would also be particularly interesting
to compare data from cantons where transparency legislation does not currently exist but is expected to
be passed soon (e.g. canton of Thurgau). The investigation of this issue would contribute to the discussion
about the relationship between active and passive transparency in a rather innovative way. All told, this study
contributes to the existing literature by providing evidence from an under-investigated country, Switzerland,
and paves the way for further research in the field of public management and communication. Nevertheless,
a more systematic comparative approach would require a harmonization of the indicators used and the
measurement preferred in studying the issue of local transparency in different jurisdictions. References Ackerman, J. M., & Sandoval-Ballesteros, I. E. (2006). The global explosion of freedom of information
laws. American Law Review, 58(1), 85–130. ( )
Adler, T. (2016, June 29). La Suisse sur la voie de la gérontocratie? Tribune de Genève, 18. Adler, T. (2016, June 29). La Suisse sur la voie de la gérontocratie? Tribune de Genève, 18. Albalate del Sol, D. (2013). The institutional, economic and social determinants of local government
transparency. Journal of Economic Policy Reform, 16(1), 90–107. DOI: https://doi.org/10.1080/174878
70.2012.759422 Bernick, E. L., Birds, J. M., Brekken, K., Gourrier, A. G., & Kellogg, L. D. (2014). Explaining county
government fiscal transparency in an age of e-government. State and Local Government Review, 46(3),
173–183. DOI: https://doi.org/10.1177/0160323X14556819 Bonsón, E., Torres, L., Royo, S., & Flores, F. (2012). Local e-government 2.0: Social media and corporate
transparency in municipalities. Government Information Quarterly, 29(2), 123–132. DOI: https://doi. org/10.1016/j.giq.2011.10.001 g
j g
Bouckaert, G., & Pollitt, C. (2011). Public management reform: A comparative analysis of NPM, the Ne
Weberian State, and New Public Governance. Oxford: Oxford University Press. Caamaño-Alegre, J., Lago-Peñas, S., Reyes-Santias, F., & Santiago-Boubeta, A. (2013). Budget
transparency in local governments: An empirical analysis. Local Government Studies, 39(2), 182–207. DOI: https://doi.org/10.1080/03003930.2012.693075 p //
g/
/
Cottier, B. (2014). Encore des résistances à l’application de la loi sur la transparence. Plaidoyer, 5, 26–31. Council of the EU. (7 October 2019). Better protection of whistle-blowers: new EU-wide rules to kick in in
2021. Retrieved from https://www.consilium.europa.eu/en/press/press-releases/2019/10/07/better-
protection-of-whistle-blowers-new-eu-wide-rules-to-kick-in-in-2021/ Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland 169 da Cruz, N. F., Tavares, A. F., Marques, R. C., Jorge, S., & de Sousa, L. (2016). Measuring local government
transparency. Public Management Review, 18(6), 866–893. DOI: https://doi.org/10.1080/14719037.201
5.1051572 Darbishire, H. (2010). Proactive transparency: The future of the right to information? (Governance Working
Paper Series No. 56598). Washington, DC: World Bank Institute. DOI: https://doi.org/10.1596/25031 de Araujo, J. F. F. E., & Tejedo-Romero, F. (2016). Local government transparency index: determinants
of municipalities’ rankings. International Journal of Public Sector Management, 29(4), 327–347. DOI:
https://doi.org/10.1108/IJPSM-11-2015-0199 Erkkilä, T. (2012). Government transparency: Impacts and unintended consequences. Basingstoke: Palgrave
Macmillan. DOI: https://doi.org/10.1057/9781137035547 Esty, D. C. (2006). Good governance at the supranational scale: Globalizing administrative law. Yale Law
Journal, 115: 1490–1562. DOI: https://doi.org/10.2307/20455663 Fairbanks, J., Plowman, K. D., & Rawlins, B. L. (2007). Transparency in government communication. Journal of Public Affairs, 7(1), 23–37. References DOI: https://doi.org/10.1002/pa.245 FSO. (2016). Salarium. Calculateur statistique de salaires 2016. Retrieved from https://www.gate.bfs.admin. ch/salarium/public/index.html#/start FSO. (2018a). Répertoire officiel des communes de Suisse. Retrieved from https://www.bfs.admin.ch/bfs/
fr/home/bases-statistiques/agvch.html O. (2018b). Vollzeitäquivalente Nach Gemeinden Und Rechtsform, Ebene Institutionelle Einheiten. Neuchâtel
Federal Statistical Office. Gallego-Álvarez, I., Rodríguez-Domínguez, L., & García-Sánchez, I.-M. (2010). Are determining factors
of municipal e-government common to a worldwide municipal view? An intra-country comparison. Government Information Quarterly, 27(4), 423–430. DOI: https://doi.org/10.1016/j.giq.2009.12.011 Grimmelikhuijsen, S., & Feeney, M. (2017). Developing and testing an integrative framework for open
government adoption in local governments. Public Administration Review, 77(4), 579–590. DOI: https://
doi.org/10.1111/puar.12689 Heald, D. (2012). Why is transparency about public expenditure so elusive? International Review of
Administrative Sciences, 78(1), 30–49. DOI: https://doi.org/10.1177/0020852311429931 ITU. (2017). Measuring the information society report 2017 (Volume 1). Geneva: International
Telecommunication Union. Kersting, N., & Vetter, A. (2003). Reforming local government in Europe. Closing the gap between democracy
and efficiency. Wiesbaden: Springer. DOI: https://doi.org/10.1007/978-3-663-11258-7 Keuffer, N., & Horber-Papazian, K. (2019). The bottom-up approach: essential to an apprehension of local
autonomy and local governance in the case of Switzerland. Local Government Studies. DOI: https://doi. org/10.1080/03003930.2019.1635019 Keuffer, N., & Mabillard, V. (2019). Administrative openness and diversity in Swiss municipalities: how
does local autonomy influence transparency practices? International Review of Administrative Sciences. DOI: https://doi.org/10.1177/0020852318823278 adner, A. (2016). Administrative reforms in Swiss municipalities over the last twenty years – the end of new
public management? Lex Localis, 14(2), 185–207. DOI: https://doi.org/10.4335/14.2.185-207(2016) Mabillard, V., & Pasquier, M. (2016). Transparency and trust in government (2007–2014): A comparative
study. NISPAcee Journal of Public Administration and Policy, 9(2), 69–92. DOI: https://doi.org/10.1515/
nispa-2016-0015 p
Meijer, A. J. (2009). Understanding modern transparency. International Review of Administrative Sciences,
75(2), 255–269. DOI: https://doi.org/10.1177/0020852309104175 eijer, A. J., Curtin, D., & Hillebrandt, M. (2012). Open government: Connecting vision and voice. Internationa
Review of Administrative Sciences, 78(1), 10–29. DOI: https://doi.org/10.1177/0020852311429533 Meijer, A. J., Curtin, D., & Hillebrandt, M. (2012). Open government: Connecting vision and voice. International
Review of Administrative Sciences, 78(1), 10–29. DOI: https://doi.org/10.1177/0020852311429533
Meilland, P. (2013). Caractéristiques des lois sur l’accès à l’information en Suisse. In M. Pasquier (Ed.), Le eilland, P. (2013). Caractéristiques des lois sur l’accès à l’information en Suisse. In M. Pasquier (Ed.), Le
principe de transparence en Suisse et dans le monde (pp. 19–35). Lausanne: PPUR. Pasquier, M. (2013). Le principe de transparence en Suisse et dans le monde. Lausanne: PPUR. Pasquier, M., & Villeneuve, J.-P. (2007). References Organizational barriers to transparency: A typology and analysis
of organizational behavior tending to prevent or restrict access to information. International Review of
Administrative Sciences, 73(1), 147–162. DOI: https://doi.org/10.1177/0020852307075701 Piotrowski, S. J., & van Ryzin, G. G. (2007). Citizen attitudes toward transparency in local
government. The American Review of Public Administration, 37(3), 306–323. DOI: https://doi. org/10.1177/0275074006296777 170 Mabillard and Keuffer: What Drives Online Transparency Practices at the Local Level? Evidence
from 2222 Municipalities in Switzerland Pratchett, L. (2004). Local Autonomy, Local Democracy and the ‘new Localism’. Political Studies, 52(2
358–375. DOI: https://doi.org/10.1111/j.1467-9248.2004.00484.x Schmidt V. (2013). Democracy and legitimacy in the European Union revisited: Input, output an
‘throughput’. Political Studies, 61(1), 2–22. DOI: https://doi.org/10.1111/j.1467-9248.2012.00962.x Steiner, R., Ladner, A., Kaiser, C., Haus, A., Amsellem, A., & Keuffer, N. (2020). Zustand und Entwicklung
der Schweizer Gemeinden. Ergebnisse des nationalen Gemeindemonitorings 2017. Glarus: Somedia
Buchverlag. Tavares, A. F., & da Cruz, N. F. (2020). Explaining the transparency of local government websites through
a political market framework. Government Information Quarterly, 37(3), 101249. DOI: https://doi. org/10.1016/j.giq.2017.08.005 Tejedo-Romero, F., & de Araujo, J. F. F. E. (2018). Determinants of local governments’ transparency in times
of crisis: Evidence from municipality-level panel data. Administration & Society, 50(4), 527–554. DOI:
https://doi.org/10.1177/0095399715607288 Welch, E. W., Hinnant, C. C., & Moon, M. J. (2005). Linking citizen satisfaction with e-government and
trust in government. Journal of Public Administration Research and Theory, 15(3), 371–391. DOI: https://
doi.org/10.1093/jopart/mui021 Worthy, B. (2017). The politics of freedom of information – How and why governments pass laws that
threaten their power. Manchester: Manchester University Press. DOI: https://doi.org/10.7228/
manchester/9780719097676.001.0001 ZHAW & IDHEAP. (2017). Nationale Gemeindeschreiberbefragung. Retrieved from http://www. andreasladner.ch/uebersicht.htm ZHAW & IDHEAP. (2018). Nationale Befragung der Gemeindeexekutivmitglieder. Retrieved from http://
www.andreasladner.ch/uebersicht.htm How to cite this article: Mabillard, V., & Keuffer, N. (2020). What Drives Online Transparency Practices at the Local
Level? Evidence from 2222 Municipalities in Switzerland. Swiss Yearbook of Administrative Sciences, 11(1), pp. 158–
170. DOI: https://doi.org/10.5334/ssas.143 Submitted: 14 June 2020 Accepted: 01 October 2020 Published: 19 October 2020 Copyright: © 2020 The Author(s). This is an open-access article distributed under the terms of the Creative Commons
Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any
medium, provided the original author and source are credited. See http://creativecommons.org/licenses/by/4.0/. Swiss Yearbook of Administrative Sciences is a peer-reviewed open access
journal published by Ubiquity Press. OPEN ACCESS Swiss Yearbook of Administrative Sciences is a peer-reviewed open access
journal published by Ubiquity Press.
|
https://openalex.org/W4394770435
|
https://www.researchsquare.com/article/rs-4243987/latest.pdf
|
English
| null |
Anxiety Disorder Amongst Clinical Medical Students at the University of Nigeria Teaching Hospital, Enugu: a Comparative Study
|
Research Square (Research Square)
| 2,024
|
cc-by
| 5,589
|
Background information Anxiety is a physiologic reaction to triggering events with the end goal of making us rise up to the occasion and get out of certain situations. Anxiety disorders
were previously called hypochondria and affect many people older than 18 years; however, they can also affect teenagers. [1] Anxiety disorders, including panic disorder with or without agoraphobia, generalized anxiety disorder, social anxiety disorder, specific phobias, and separation
anxiety disorder, are the most prevalent mental disorders and are associated with immense health care costs and a high burden of disease [2]. Of the barrage
of Anxiety disorders, Specific phobias are the most common, with a prevalence of 10.3%; panic disorders (with or without agoraphobia) are the next most
common, with a prevalence of 6.0%; followed by social phobias (2.7%); and generalized anxiety disorders (2.2%). [3] Medical education is considered to be one of the most academically and emotionally demanding training programs available for any profession, and
consequently, the time and emotional commitment necessary for medical students to devote to their training are extensive. Such demands and stress cause a
negative effect on students’ psychological well-being, thus, precipitating anxiety disorders. [4] Psychological distress (as can be caused by anxiety disorders)
among medical graduates is thought to be associated with suboptimal patient care, patient safety and professionalism [5], highlighting the massive toll
anxiety disorders take on patient care, by extension. Anxiety disorders are the most common mental disorders, affecting approximately 30% of adults during their lifetime [6], with women being more likely than
men to have anxiety symptoms, with a lifetime incidence ratio of 1.7:1[7]. In the United States, anxiety disorders are the most common mental illness, affecting
approximately 40 million adults each year (18.1% of the population). It is highly treatable, yet only 36.9% of patients seek medical aid. [8] Similarly, in Nigeria, anxiety disorders again predominate compared to other mental disorders, with a lifetime prevalence rate of 5.7% and a 12-month
prevalence rate of 4.1%, with specific phobias being the most common subtype. [9] If an anxiety disorder is not detected early enough, it may result in a slow
recovery and affect or worsen the person’s physical health. Evidence points to comorbidities being associated with anxiety disorders [10]; therefore, anxiety
disorders need to be identified and managed promptly to prevent deterioration in the health of patients. Abstract Anxiety disorders are combinations of emotional disorders that have profound effects on the mental status of individuals. One of the most common
presentations is a panic attack, in which students experience attacks that are especially close to tests and examinations due to the cumbersome academic
workload. This paper reviews the effect of anxiety disorders among medical students at the University of Nigeria Enugu Campus. An online questionnaire was distributed
to the 3rd, 4th, and 5th MBBS classes in an attempt to determine the prevalence and knowledge of anxiety in these classes, and any known coping mechanisms
and to perform a comparative study on socio-demographic, academic, and personal factors. The results revealed a preponderance in females and fear of failure and a high dependence on receiving emotional support from family, praying and
meditating as coping mechanisms. Hopefully, this study will inform academic authorities on the need to adjust syllables due to increased workload as a contributing factor of anxiety disorder
and school authorities on the need for a closed student-lecturer interaction. Anxiety Disorder Amongst Clinical Medical Students at the University of
Nigeria Teaching Hospital, ENUGU CAMPUS: a Comparative Study Page 1/10 Introduction Background information Literature Review Many students perform poorly because of anxiety. This has contributed to their adequate preparation for exams, causing some students to easily forget what
they read and preventing them from being unable to produce the information in an appropriate way. Due to these few observations concerning the effect of anxiety, a good study of anxiety among students, particularly clinical medical students, will help in
discovering the causes of anxiety disorders and the underlying mechanisms involved. Anxiety disorders are mental health disorders characterized by feelings of worry or fear that are strong enough to interfere with one’s activity. Anxiety disorders are mental health disorders characterized by feelings of worry or fear that are strong enough to interfere with one’s activity. Previous studies examining anxiety disorder separately are rare despite the noted effect of anxiety on the academic performance of medical students, on the
generation of poor coping strategies such as the use of alcohol and nicotine, and on the development of long-term effects on their performance as doctors in
terms of poor work efficacy. Anxiety disorders, as a topic, have been neglected, and there is limited research on anxiety. There is a knowledge gap on anxiety disorders in the developing population at large and, unfortunately, among medical students in Nigeria despite the
psychopathological effect of these disorders. Therefore, this study will contribute greatly to enlightening the public at large on the increasing burden of anxiety
disorders among people, particularly medical students, and thus lead to the development of policies, such as the formation of a student-friendly environment
and the development of counseling services and various forms of psychological therapy, that will help in curbing the prevalence of anxiety disorders among
medical students. There is no known objective way to measure the level of difficulty a university course presents; however, there is widespread agreement that some courses are
more difficult than most and that medicine and surgery as a course is constantly thought to be among the top 10 when ranked according to the level of
difficulty and intensity of challenge. Medical students experience high levels of stress and anxiety (more so than do the general population), possibly because
they have voluminous materials to memorize, sleep deprivation, social isolation, and so forth. In addition, many medical schools are structured to foster
competition rather than cooperation, resulting in the aggravation of present stress. Background information Depression is also associated with significant rates of
substance misuse, depressive and manic symptoms, as well as other consequences, such as decreased productivity in study studies with resultant poor
academic students’ performance in students with low self-esteem, lack of self-confidence, decreased memory span, lack of concentration and prolonged
school years of stay. To the best of our knowledge, there has not been a comparative study on the prevalence and effects of anxiety disorders amongst among clinical medical
students at the University of Nigeria, Enugu Campus. Thus, this study was designed to determine the prevalence of anxiety disorders among clinical medical
students, the effects of anxiety disorders on their academic performance, the associated factors and the coping strategies adopted by the affected individuals. Health and education are the two cornerstones of human capital and form the basis of an individual’s economic productivity [11]. Anxiety disorders among
students is a serious health challenge because they can interfere with these two cornerstones and alter their future potential. Fortunately, studies on the
subject are rapidly growing, although disproportionately across regions. Generalization with foreign findings may not be helpful because of differences in the
value of health across different countries, health insurance, and living conditions of the students, as well as in the structure of the students’ support systems. Medical students, by virtue of their hectic daily schedules and demanding nature of the course are at increased risk of anxiety disorders; hence, there is a need
to properly elucidate its possible causes, varied presentations and institute therapies. Compared to the general population, medical students have greater
levels of anxiety. [12] Medical students in Nigeria are prone to a spectrum of anxiety disorders. This susceptibility is influenced by sociodemographic characteristics.[13] These
characteristics can include age at school, gender, allowances, relationships with friends or parents, and marital status. Page 2/10 Page 2/10 This study contributes immeasurably to the literature on anxiety disorders among medical students at the University of Nigeria. This comparative study
therefore aimed to fill some of these key research gaps by studying anxiety disorders, thus helping us better understand the clinical features and possible
factors associated with anxiety disorders among medical students at the UNIVERSITY OF NIGERIA, ENUGU CAMPUS with an end game of eradicating anxiety
disorder through the development of better prevention strategies, treatment programs and rehabilitation packages. Specific Objectives e the prevalence of anxiety disorders among clinical medical students at the University Of Nigeria, Enugu Campus 1. To determine the prevalence of anxiety disorders among clinical medical students at the University Of Nige 1. To determine the prevalence of anxiety disorders among clinical medical students at the University Of Nigeria, Enugu Campus. 2. To assess personal and socio-demographic sociodemographic factors associated with anxiety disorder disorders among clinical medical students at the
University Of Nigeria, Enugu Campus 2. To assess personal and socio-demographic sociodemographic factors associated with anxiety disorder disorders among clinical medical students at the
University Of Nigeria, Enugu Campus 3. To ascertain the effects of anxiety disorder disorders on the academic and social lives of clinical medical students at the University Of Nigeria, Enugu
Campus 3. To ascertain the effects of anxiety disorder disorders on the academic and social lives of clinical medical students at the University Of Nigeria, Enugu
Campus 4. To compare the prevalence of anxiety disorder disorders among clinical medical students in the University Of Nigeria, Enugu Campus
5. To assess coping strategies for anxiety disorders among clinical medical students at the University Of Nigeria, Enugu Campus. 5. To assess coping strategies for anxiety disorders among clinical medical students at the University Of Nigeria, Enugu Campus. General Objectives This study aims aimed to determine the prevalence and associated factors of anxiety amongst disorders among clinical medical students at the University
of Nigeria, Enugu campus Literature Review From this study, suggestions such as the creation of sensitization programs for mental disorders, the provision of mandatory
counseling services for students at least once in every academic session and the provision of help-lines for students who would like to be anonymous were
made by the people who did this study with the aim of reducing the prevalence of anxiety and depression, which is also a comorbidity and thus the long-term
effects of these mental disorders. One limitation of this study is that it focused only on one institution. [13] respondents. The study determined that the year of study with the highest prevalence of anxiety and depression was year 3, and the year of study with the
lowest prevalence was year 6. From this study, suggestions such as the creation of sensitization programs for mental disorders, the provision of mandatory
counseling services for students at least once in every academic session and the provision of help-lines for students who would like to be anonymous were
made by the people who did this study with the aim of reducing the prevalence of anxiety and depression, which is also a comorbidity and thus the long-term
effects of these mental disorders. One limitation of this study is that it focused only on one institution. [13] A.O. Coker et al. studied the “sociodemographic correlates and symptoms of depression, anxiety and stress among a sample of Nigerian medical students.’’
This was a cross-sectional descriptive study of 240 medical students in the 2nd to 6th academic years of study. The Depression Anxiety Stress Scale 21
(DASS-21) was analyzed using the International Business Machine Statistical Package for the Social Science version 18 (IBM-SPSS). Unlike previous studies
that showed a high prevalence of these disorders, this study showed a low prevalence of depression and anxiety, which was attributed to the close proximity
of the students’ hostel to the college and the friendly atmosphere of the school. According to the sociodemographic relationship with the incidence of NAFLD,
individuals aged 23-28 years experienced more depression, anxiety and stress than did those aged 29-34 years. Male participants experienced more
depression and anxiety than female participants did, although female students were known to be more stressed. In this study, it was also noted that some
students resorted to poor coping habits. The limitation of this study was the use of a homogenous sample of medical students from one university. Methodology
STUDY AREA The study was carried out at the University of Nigeria, the Enugu Campus, and the Ituku Ozalla campus as well as at the University of Nigeria Teaching
Hospital, Old Site, Enugu. INCLUSION CRITERIA All the clinical medical students were from the University of Nigeria, Nsukka. The sample included 4th, 5th, and 6th year medical students. It also included the
senior 3rd year medical students who just started their clinical program STUDY DESIGN The study design was a cross-sectional epidemiological study of the descriptive type among Clinical medical st
Hospital, Enugu. The study design was a cross-sectional epidemiological study of the descriptive type among Clinical medical students at the University of Nigeria Teaching
Hospital, Enugu. STUDY POPULATION Undergraduate clinical medical students at the University of Nigeria, Enugu Campus. There are different hostels for the different classes of clinical medical
students. The clinical medical students in the University of Nigeria Teaching Hospital Ituku and Oldsite, and the clinical students in the University of Nigeria
Enugu Campus participated Literature Review [1] In a meta-analysis intended to determine the global prevalence of anxiety among medical students performed by Travis Tian-Ci Quek et al. in 2019, a total of
sixty-nine studies were pooled and analyzed. The studies included 40,438 medical students. Eighteen studies were from Asia, twenty-one from the Middle East,
thirteen from Europe, ten from South America, four from North America, two from Oceania and one from Africa. The sample sizes of the studies ranged from
73 to 10,140, and screening instruments such as BAS 21, DASS 21, HADS and GAD 7 were utilized to assess the presence of anxiety disorders in medical
students. The mean age of the individuals ranged from 18.02 years to 25.10 years. This meta-analysis revealed that the average prevalence of NAFLD among
the total number of studies pooled was 35.4%. When the prevalence was stratified by sex, we found that female medical students had a greater incidence of
anxiety (38.0%) than male students did (27.6%), but this difference was not statistically significant (p = 0.16). It was suggested that destigmatization of
mental illness and the culture of help-seeking behavior should start from the school’s administration, which includes making rules that would favor an
increase in the help-seeking behavior of those with mental illness.[4] In another study by Naomi A. Dike-Israel et al.on the prevalence and comorbidity of depression and anxiety among medical students at Babcock University,
Ogun State, Nigeria, a cross-sectional survey was conducted with undergraduate medical students who were recruited randomly from classes. The sample
included 225 medical students (68.8% women and 30.2% men), with a mean age of 19.09 years (±2.14 S.D.). An online survey utilizing the Beck Anxiety
Inventory (BAI) was administered to make a provisional diagnosis of anxiety and its severity. The results indicated a 28.4% prevalence of anxiety among the Page 3/10 Page 3/10 respondents. The study determined that the year of study with the highest prevalence of anxiety and depression was year 3, and the year of study with the
lowest prevalence was year 6. EXCLUSION CRITERIA UNEC students from other faculties Preclinical students at the Nsukka and Enugu campuses Preclinical and Clinical students who were not available during our data collection
SAMPLING METHOD Literature Review [14] Anita H Laidlaw studied social anxiety at the University of St Andrews in 2009 among a total of 247 medical students, 60% of whom were female. The
students completed a questionnaire survey measuring levels of social anxiety and attitudes toward communication skills teaching. A total of 300 medical
students were included, 247 of whom completed the questionnaire (82% response rate). The questionnaire included the social phobia scale, social interaction
anxiety scale, reduced version of the Communication Skills Attitude Scale and several demographic questions. In comparison with that of the other subgroups,
the prevalence of social anxiety was lower among medical students. Compared with their male counterparts, female students had a greater level of social
anxiety. One of the studies the author examined noted that adolescents suffering from high levels of social anxiety may be less likely to achieve the grades to
enable them to apply for medical school. The study revealed that social anxiety contributes to a negative attitude toward teaching communication skills and
may impact participation in group workshops. The impact of social anxiety on the ability of students to communicate with potential patients during practical
examinations was not examined in this study. The author also noted that social anxiety was positively correlated with alcohol dependence and problems
caused by alcohol. [15] DATA COLLECTION This study was performed by collecting primary data via a self-administered online questionnaire, which was completed by the respondents. The
questionnaire was pretested at Enugu State University Teaching Hospital Parklane It had eight sections that assessed the following It had eight sections that assessed the following SECTION A: Personal and Sociodemographic Data SECTION A: Personal and Sociodemographic Data SECTION B: Parental Demographic Data SECTION C: Level of awareness of anxiety disorders SECTION D: Assessment of prevalence of anxiety disorder using the Beck’s Anxiety Inventory (1988) with a modified time frame assessing for presence of
anxiety symptoms since 2nd MBBS. The instrument consists of 21 items that are answered using a multiple choice scale. Each item has a score of 0–3, with
higher scores indicating more severe symptoms. The inventory divides the scores into low (minimal and mild), moderate and severe anxiety. Scores ranged
from 0-21 for mild anxiety, 22-35 for moderate anxiety and 36-63 for severe anxiety. The BAI measures emotional, cognitive and physiological symptoms of anxiety. SECTION E: Assessment of coping strategies SECTION F: Effects of anxiety disorders on the Academic Life of Clinical Students SECTION G: Effects of anxiety disorders on the Social Life of Clinical Students SECTION H: Factors associated with anxiety SECTION H: Factors associated with anxiety d using the Statistical Package for the Social Sciences (SPSS) version 26.0. The data are presented in the tables. ata analysis was performed using the Statistical Package for the Social Sciences (SPSS) version 26.0. The data a Ethical approval was obtained prior to the field work from the Department of Community Medicine UNTH as well as the Student Affairs Department UNN,
Enugu and Ituku Ozalla Campuses. The respondents’ data were carefully handled. eld work from the Department of Community Medicine UNTH as well as the Student Affairs Department UNN,
pondents’ data were carefully handled. Ethical approval was obtained prior to the field work from the Department of Community Medicine UNTH as we
Enugu and Ituku Ozalla Campuses. The respondents’ data were carefully handled. N = 1.962 × 0.284 (1-0.284) The addition of 10% to compensate for attrition will increase the sample size too
10% of 312.467 = 31.2467 Minimum Sample Size = 312.467 + 31.2467 = 343.7137 Approximately 344 students probability sampling via the simple random sampling technique was used. SAMPLING METHOD Page 4/10 Minimum sample size, n = Z2 p(1-p)/d2
where Z = 1.96 at the 95% confidence limit
P = Prevalence of anxiety disorder from a previous study (28.4%)
d = Margin of error tolerated, usually 5% (or 0.05) N = 1.962 × 0.284 (1-0.284)
(0.05)2
=312.467 students Discussion A total of 342 respondents who freely responded to this research topic were involved in this study. A total of approximately 157 students had anxiety disorders
—86 (26.61%) had moderate anxiety, and 71 (21.93%) had severe anxiety—for a total prevalence of 48.54%. These findings were obtained based on previous
methods involving anxiety prevalence scoring system. According to the new scoring system for anxiety, a total of 213 students had anxiety disorders, 139
(40.6%) had severe anxiety, and 74 (21.6%) had moderate anxiety disorders. The newer classification yielded a higher prevalence, whereas the application of
the older classification yielded lower and near-global prevalence; the difference observed could be due to methodology implication limitations. The prevalence
rate (both in the new and old versions) is far greater than the previous prevalence rate obtained from various studies; the study performed at Babcock
University reported a prevalence rate of 28.4%. This can be attributed to the standard that is placed by the school authority for passing a professional
examination in school. This can also be attributed to the workload, which is inversely proportional to the amenities needed by students to cope well in school,
such as a poor light supply for reading, poor water supply, poor attitudes of some lecturers toward students, long distance between the hostel area and the
hospital environment for 3rd year, 4th year and 5th year students. This could also be attributed to the current state of mind of some students because the 4th-
year medical students were experiencing examination preparation during our data collection. This study revealed a prevalence of 60.5% (51), 46.6% (39), 42.7% (35) and 50.2% (41%) among 3rd year, 4th year, 5th year and 6th year clinical medical
students, respectively. This shows a difference between the rate in the 3rd year and that in other years. There was a slight difference in the rate of anxiety
among fourth- and fifth-year clinical medical students, while there was no significant difference in the rate of anxiety among sixth-year and third-year clinical
medical students; however, there was a significant difference in the prevalence of anxiety between 3rd- and sixth-year medical students and between 4th- and
fifth-year medical students. Third-year medical students had the highest rate of anxiety, followed by sixth-year, 4th year and, finally, fifth-year medical students. In comparison with the study performed by Naomi A. Effects on the academic and social lives of students (Figure 1 and 2) In this study, it was found that anxiety affected the academic lives of medical students, with most students worrying about not putting in enough effort (65%),
losing concentration during study (62.3%) and being forgetful (50.2%) being the top three effects. In contrast, anxiety had little effect on the social life of
students. Response rate and characteristics of participants (Tables 1 and 2) Of the 1265 clinical medical students enrolled at the University of Nigeria Teaching Hospital, Enugu,342 (27%) participated in the research. A total of 224
(65.5%) of them were aged between 21 and 25 years, while 75 (21.9%) were aged between 16 and 20 years. The rest were older than 25 years. The mean age
of the participants was 22.59 ±2.67 years. There was almost equal gender representation, with 172 females (50.3%) and 170 males (49.7%). The year of study
of the respondents was distributed as follows: 28.7% in 300 L, 21.3% in 400 L, and 22.2% in 500 L; 27.8% in 600 L. In this study, 57.6% had monthly incomes
greater than 20,000 naira, 98% were unmarried, and 83.9% had their parents married still. When asked about their awareness of anxiety, 97.4% had heard Page 5/10 Page 5/10 about anxiety, with approximately 60.2% hearing about it in the mass media. The respondents were asked to self-rate their anxiety levels, and 27.5% admitted
that they were overly anxious. Approximately 78.7% of respondents thought people with anxiety disorders should be counseled as against being ignored or
given medications. A majority (86%) believe that anxiety can be cured. Coping strategies (Figure 3) The five coping strategies medical students employed in this study were praying and meditating (67.2%), seeking family support (66.6%), decreasing study
intensity (62%), Strolling (58.2%) and seeking religious ministers (53.8%). Prevalence of anxiety symptoms among medical students (Table 4) When the BAI (with adjusted time range) was self-administered, moderate anxiety symptoms were prevalent in 26.6% of the students, and 21.9% of the
students had severe anxiety according to the scoring of the 1988 version of the BAI. Considering the scoring of the 1992 BAI, moderate and severe symptoms
had incidences of 21.6% and 40.6%, respectively. Associations between student characteristics (Tables 5 and 6) This study revealed that anxiety was significantly associated with sex (p=0.001, x2=13.77), fear of failure of professional exams (p≤0.05, x2=22.5), sleepless
nights (p=0.002, x2=28.47), parental pressure (p≤0.05, x2=22.08), fear of fellow students (p≤0.05, x2=13.13), academic stress (p=0.02, x2=8.16) and
overdemanding lecturers (p≤0.05, x2=14.44). Conclusion This study showed that anxiety disorders are a menace in the lives of clinical medical students at the University of Nigeria Enugu Campus. This finding
shows that proper education is important for informing school management and the population at large about anxiety and its effect on an individual. Proper
education needs to be given on the causes, clinical features, effects, management and ways of preventing anxiety to reduce the prevalence of this disease. This is due to the negative effects of anxiety both on health and in other areas of life. The discovery of the involvement of students in religious activities shows that religious leaders can be involved in the prevention and multidisciplinary
management of anxiety. They should be taught about anxiety disorders in detail so that they can easily discover any tail signs of anxiety disorders in any
individual seeking counseling to help in the management of such people. According to our study, female students had the highest incidence of anxiety disorders. Proper study needs to be performed to identify the factors that
could predispose a female to anxiety, and ways to reduce these factors should be identified. Even though finances were noted by an insignificant number of
people, this need to be addressed; school management should try to establish scholarship schemes for students who are not financially buoyant. Finally, the
almost nonsignificant associations of the various sociodemographic factors with anxiety show that there should always be a high index of suspicion for
anxiety irrespective of religion, ethnicity, marital status and economic Discussion Dike, 3rd-year students had the highest rate of anxiety, while the final ear students had the lowest In this study, more females than male clinical medical students had a higher rate of anxiety. This finding is in line with the findings of the study performed
by A.O. Coker , where female students had the highest prevalence of anxiety. Those aged approximately 21-25 years also had a greater incidence of anxiety
disorders than did the other age groups. Among the 12 students who smoked, a few reported symptoms of anxiety. Out of 135 students who consumed
alcohol, 59 had anxiety disorders. The results of the present study revealed that anxiety was associated with variable factors, which included academic stress,
sleepless nights, fear of failing a professional exam, fear of loved one, and overdemanding lecturers. Other factors, such as financial status, fellow student
status, caffeine intake, fear of contracting sexually transmitted disease, social isolation and obesity, contributed little to the overall incidence of anxiety
disorders. Page 6/10 In this study, it was noted that anxiety caused some students to lose ,concentration while studying and to do poorly on their exams, while in some students,
it made them put forth more effort into their studies. It also affected some students by helping them easily forget what they had read. In terms of social
effects, it made students difficult to talk to someone in authority, but it had little effect on making them aggressive, making them have difficulty
communicating with their colleagues and carrying out daily routine tasks. The most commonly observed coping strategies that were used in those with anxiety disorders in our study were engaging in praying, receiving emotional
support from family members, reducing hours of study, resorting to pastors, engaging in exercise and strolling out with friends. Few students engaged in
clubbing activities, consumed alcohol to feel better, consumed psychoactive drugs, visited hospitals, exercised, sought counseling from lecturers, consulted
traditionalists or took herbal drugs. References 1. Anxiety disorder. Anxiety Disorder - Background Information (weebly.com) 1. Anxiety disorder. Anxiety Disorder - Background Information (weebly.com) 2. Bandelow B, Michaelis S. Epidemiology of Anxiety Disorders in the 21st Century [Internet]. Dialogues in clinical neuroscience. Les Laboratoires Servier;
2015 [cited 2021Nov19]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4610617/ 2. Bandelow B, Michaelis S. Epidemiology of Anxiety Disorders in the 21st Century [Internet]. Dialogues in clinical neuroscience. Les Laboratoires Servier;
2015 [cited 2021Nov19]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4610617/ 3. F; T. Anxiety disorders: A review of current literature [Internet]. Dialogues in clinical neuroscience. U.S. National Library of Medicine; 2017 [cited
2022Jan3]. Available from: https://pubmed.ncbi.nlm.nih.gov/28867933/ 3. F; T. Anxiety disorders: A review of current literature [Internet]. Dialogues in clinical neuroscience. U.S. National Library of Medicine; 2017 [cited
2022Jan3]. Available from: https://pubmed.ncbi.nlm.nih.gov/28867933/ 4. Tian-Ci Quek T, Wai-San Tam W, X. Tran B, Zhang M, Zhang Z, Su-Hui Ho C, et al. The global prevalence of anxiety among medical students: A meta-
analysis [Internet]. MDPI. Multidisciplinary Digital Publishing Institute; 2019 [cited 2021Nov19]. Available from: https://www.mdpi.com/1660-
4601/16/15/2735 4. Tian-Ci Quek T, Wai-San Tam W, X. Tran B, Zhang M, Zhang Z, Su-Hui Ho C, et al. The global prevalence of anxiety among medical students: A meta-
analysis [Internet]. MDPI. Multidisciplinary Digital Publishing Institute; 2019 [cited 2021Nov19]. Available from: https://www.mdpi.com/1660-
4601/16/15/2735 5. AL; STDBKAWJEB. Burnout and self-reported patient care in an Internal Medicine Residency Program [Internet]. Annals of internal medicine. U.S. National Library of Medicine; 2002 [cited 2022Jan3]. Available from: https://pubmed.ncbi.nlm.nih.gov/11874308/ 5. AL; STDBKAWJEB. Burnout and self-reported patient care in an Internal Medicine Residency Program [Internet]. Annals of internal medicine. U.S. National Library of Medicine; 2002 [cited 2022Jan3]. Available from: https://pubmed.ncbi.nlm.nih.gov/11874308/ 5. AL; STDBKAWJEB. Burnout and self-reported patient care in an Internal Medicine Residency Program [Internet]. Annals of internal medicine. U.S. National Library of Medicine; 2002 [cited 2022Jan3]. Available from: https://pubmed.ncbi.nlm.nih.gov/11874308/ 6. American Psychiatric Association. What Are Anxiety Disorders? [Internet]. What are anxiety disorders? 2021 [cited 2021Nov19]. Available from:
https://www.psychiatry.org/patients-families/anxiety-disorders/what-are-anxiety-disorders 6. American Psychiatric Association. What Are Anxiety Disorders? [Internet]. What are anxiety disorders? 2021 [cited 2021Nov19]. Available from:
https://www.psychiatry.org/patients-families/anxiety-disorders/what-are-anxiety-disorders 7. McLean CP, Asnaani A, Litz BT, Hofmann SG. Gender differences in anxiety disorders: Prevalence, course of illness, comorbidity and burden of illness
[Internet]. Journal of psychiatric research. U.S. National Library of Medicine; 2011 [cited 2021Nov19]. Available from:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3135672/ 7. McLean CP, Asnaani A, Litz BT, Hofmann SG. References Asian Journal of Medicine and Health. 2021;19(4): 46-55. 13. Naomi A. Dike-Israel, Dora O. Akinboye. Prevalence and Comorbidity of Depression and Anxiety among Medical Students in Babcock University, Ogun state
Nigeria. Asian Journal of Medicine and Health. 2021;19(4): 46-55. 14.A.O Coker, O.O Coker, D Sanni. Sociodemographic Correlates and Symptoms of Depression, Anxiety and Stress Among a Sample of Nigerian Medical
Students. Nigerian Journal of Basic and Clinical Sciences. 2018; 15:58-62. 14.A.O Coker, O.O Coker, D Sanni. Sociodemographic Correlates and Symptoms of Depression, Anxiety and Stress Among a Sample of Nigerian Medical
Students. Nigerian Journal of Basic and Clinical Sciences. 2018; 15:58-62. 15. Anita H. Laidlaw. Social Anxiety in Medical Students: Implications for communication skills teaching. Medical Teacher. 2019; 31(7): 649-654. 15. Anita H. Laidlaw. Social Anxiety in Medical Students: Implications for communication skills teaching. Medical Teacher. 2019; 31(7): 649-654. References Gender differences in anxiety disorders: Prevalence, course of illness, comorbidity and burden of illness
[Internet]. Journal of psychiatric research. U.S. National Library of Medicine; 2011 [cited 2021Nov19]. Available from:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3135672/ 8. Anxiety and Depression Association of America. Facts & Statistics: Anxiety and Depression Association of America, ADAA [Internet]. Facts &
Statistics | Anxiety and Depression Association of America, ADAA. 2021 [cited 2022Jan3]. Available from: https://adaa.org/understanding-anxiety/facts-
statistics 8. Anxiety and Depression Association of America. Facts & Statistics: Anxiety and Depression Association of America, ADAA [Internet]. Facts &
Statistics | Anxiety and Depression Association of America, ADAA. 2021 [cited 2022Jan3]. Available from: https://adaa.org/understanding-anxiety/facts-
statistics 9. Gureje O. Lifetime and 12-month prevalence of mental disorders in ... [Internet]. Lifetime and 12-month prevalence of mental disorders in the Nigerian
Survey of Mental Health and Well-Being. 2006 [cited
2022Jan3].Availablefrom:https://www.researchgate.net/publication/7131891_Lifetime_and_12month_prevalence_of_mental_disorders_in_the_Nigerian_Survey
Being Page 7/10
11. World Health Organization. Macroeconomics and health: Investing in health for Economic Development: Executive summary/report of the
commission on macroeconomics and health [Internet]. World Health Organization. World Health Organization; 1970 [cited 2021Nov19]. Available from: Page 7/10
11. World Health Organization. Macroeconomics and health: Investing in health for Economic Development: Executive summary/report of the
commission on macroeconomics and health [Internet]. World Health Organization. World Health Organization; 1970 [cited 2021Nov19]. Available from: Page 7/10
11. World Health Organization. Macroeconomics and health: Investing in health for Economic Development: Executive summary/report of the
commission on macroeconomics and health [Internet]. World Health Organization. World Health Organization; 1970 [cited 2021Nov19]. Available from: https://apps.who.int/iris/handle/10665/42463 12. TD; DLNTMRS. Systematic review of depression, anxiety, and other indicators of psychological distress among U.S. and Canadian Medical Students
[Internet]. Academic medicine : journal of the Association of American Medical Colleges. U.S. National Library of Medicine; 2006 [cited 2022Jan3]. Available
from: https://pubmed.ncbi.nlm.nih.gov/16565188/ 12. TD; DLNTMRS. Systematic review of depression, anxiety, and other indicators of psychological distress among U.S. and Canadian Medical Students
[Internet]. Academic medicine : journal of the Association of American Medical Colleges. U.S. National Library of Medicine; 2006 [cited 2022Jan3]. Available
from: https://pubmed.ncbi.nlm.nih.gov/16565188/ 13.Benjamin J. Sadock, Samoon Ahmad, Virginia A. Sadock. Kaplan and Sadock’s Pocket Handbook of clinical psychiatry,6th edition [textbook];New York,
Wolters Kluwer(publisher),1995;chapter 12, 250-273. 13.Benjamin J. Sadock, Samoon Ahmad, Virginia A. Sadock. Kaplan and Sadock’s Pocket Handbook of clinical psychiatry,6th edition [textbook];New York,
Wolters Kluwer(publisher),1995;chapter 12, 250-273. 13. Naomi A. Dike-Israel, Dora O. Akinboye. Prevalence and Comorbidity of Depression and Anxiety among Medical Students in Babcock University, Ogun state,
Nigeria. Figures Figure 1 EFFECT OF ANXIETY ON THEIR ACADEMICS Page 8/10 Page 8/10 COPING STRATEGIES OF MEDICAL STUDENTS COPING STRATEGIES OF MEDICAL STUDENTS Figure 2 Figure 2 Page 9/10 Page 10/10
Figure 3
COPING STRATEGIES OF MEDICAL STUDENTS
Supplementary Files
This is a list of supplementary files associated with this preprint. Click to download. Tables1.jpg
Tables2.jpg
Tables3.jpg
Tables4.jpg
Tables5.jpg
Tables6.jpg
Tables7.jpg
Tables8.jpg Figure 3 COPING STRATEGIES OF MEDICAL STUDENTS Supplementary Files This is a list of supplementary files associated with this preprint. Click to download. Tables1.jpg
Tables2.jpg
Tables3.jpg
Tables4.jpg
Tables5.jpg
Tables6.jpg
Tables7.jpg
Tables8.jpg Page 10/10
|
https://openalex.org/W3049644655
|
https://discovery.ucl.ac.uk/10109851/7/Carmalt_d0sc90149k.pdf
|
English
| null |
Correction: Recent advances in low oxidation state aluminium chemistry
|
Chemical science
| 2,020
|
cc-by
| 194
|
The authors regret that incorrect details were given for ref. 69 in the original article. The correct version of ref. 69 is given below as
ref. 1. ref. 1. The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. Open Access Article. Published on 17 August 2020. Downloaded on 9/11/2020 1:04:05 PM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Cite this: Chem. Sci., 2020, 11, 9028 Katie Hobson, Claire J. Carmalt and Clare Bakewell* DOI: 10.1039/d0sc90149k Correction for ‘Recent advances in low oxidation state aluminium chemistry’ by Katie Hobson et al., Chem. Sci., 2020, DOI: 10.1039/d0sc02686g. The authors regret that incorrect details were given for ref. 69 in the original article. The correct version of ref. 69 is given below as
ref 1 References 1 S. J. Bonyhady, D. Collis, N. Holzmann, A. J. Edwards, R. O. Piltz, G. Frenking, A. Stasch and C. Jones, Nat. Commun., 2018, 9, 3079. Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK. E-mail: c.bakewell@ucl.ac.u 9028 | Chem. Sci., 2020, 11, 9028 This journal is © The Royal Society of Chemistry 2020
|
https://openalex.org/W3213923503
|
https://epub.wupperinst.org/files/7895/7895_Witte.pdf
|
English
| null |
Social Acceptance of Carbon Capture and Storage (CCS) from Industrial Applications
|
Sustainability
| 2,021
|
cc-by
| 20,389
|
Citation: Witte, K. Social Acceptance
of Carbon Capture and Storage (CCS)
from Industrial Applications. Sustainability 2021, 13, 12278. https://doi.org/10.3390/su132112278 sustainability sustainability sustainability sustainability Review
Social Acceptance of Carbon Capture and Storage (CCS) from
Industrial Applications Katja Witte Wuppertal Institute for Climate, Environment and Energy, Division Future Energy and Industry Systems,
Doeppersberg 19, 42103 Wuppertal, Germany; katja.witte@wupperinst.org; Tel.: +49-202-2492-218 Abstract: To limit global warming, the use of carbon capture and storage technologies (CCS) is
considered to be of major importance. In addition to the technical–economic, ecological and political
aspects, the question of social acceptance is a decisive factor for the implementation of such low-
carbon technologies. This study is the first literature review addressing the acceptance of industrial
CCS (iCCS). In contrast to electricity generation, the technical options for large-scale reduction of
CO2 emissions in the energy-intensive industry sector are not sufficient to achieve the targeted
GHG neutrality in the industrial sector without the use of CCS. Therefore, it will be crucial to
determine which factors influence the acceptance of iCCS and how these findings can be used for
policy and industry decision-making processes. The results show that there has been limited research
on the acceptance of iCCS. In addition, the study highlights some important differences between
the acceptance of iCCS and CCS. Due to the technical diversity of future iCCS applications, future
acceptance research must be able to better address the complexity of the research subject. Keywords: carbon capture; acceptance; public perception; industrial applications; literature review;
knowledge; awareness; communication
Citation: Witte, K. Social Acceptance
of Carbon Capture and Storage (CCS)
from Industrial Applications. Sustainability 2021, 13, 12278. https://doi.org/10.3390/su132112278
Academic Editors: Georgios
Tsantopoulos and Evangelia
Karasmanaki
Received: 25 September 2021
Accepted: 3 November 2021
Published: 7 November 2021 1. Introduction To limit global warming to 1.5 ◦C, the use of carbon capture and storage technologies
(CCS) is considered to be of major importance [1–5]. In international parlance, CCS stands
for a mix of technological processes for CO2 capture and storage. These are large-scale
processes in which carbon dioxide (CO2) is captured from huge CO2 point sources. The
captured CO2 is transported via pipeline, ship, or heavy transport and then either reused
or injected underground into a suitable geological formation (onshore or offshore) [6]. The use of CO2 capture processes is feasible both in fossil-fired power plants for
electricity generation and in energy-intensive industrial processes (for example, steel
or cement plants) and could enable a significant reduction in CO2 emissions in these
applications. According to the International Energy Agency [7], fossil-fired power plants
accounted for about 42.5% of total global CO2 emissions in 2013. In comparison, the share
of CO2 emissions caused by industrial activities was around 25%. Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
iations. In recent years, the discussion around CCS has increasingly focused on its use in
the context of industrial facilities (in the following, the term “industrial CCS” is referred
to as iCCS). This is mainly because the technical options for the extensive reduction of
CO2 emissions in the area of energy-intensive industries without the use of iCCS are not
sufficient to achieve the targeted GHG neutrality in the industrial sector. Ref. [4] However,
what exactly distinguishes the term iCCS from the classic CCS application? Fossil fuels
are an essential input to the production process of the steel, cement, lime and chemical
industries, the so-called energy-intensive industries. These fuels are used in the industries
for their chemical and physical properties rather than as a primary energy source for power
generation, as is the case with CCS [8]. However, unlike electricity generation, it is not
possible to replace fossil fuels with renewable energy sources to reduce emissions. This
literature review focuses explicitly on the application of CCS to these industrial processes. Copyright: © 2021 by the author. Licensee MDPI, Basel, Switzerland. This article is an open access article
distributed
under
the
terms
and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/). https://www.mdpi.com/journal/sustainability Sustainability 2021, 13, 12278. 1. Introduction https://doi.org/10.3390/su132112278 Sustainability 2021, 13, 12278 2 of 29 The debate to date on the commercial introduction of CCS in fossil-fired power plants
(abbreviated below as CCS) has made it clear that numerous other factors are relevant in
addition to purely technical and economic indicators. On the part of policymakers, there is
a need for a reliable agreement and strategy on the future role of CCS, taking into account
international developments around CCS as well as other technological climate protection
paths. This will create planning and legal certainty for industry and society and enable the
early development of CO2 infrastructure. y
p
Another essential factor, which is the focus of this publication, is the social perception
of iCCS technologies and the possible assessment of their future acceptance. Previous
research on CCS acceptance has made it clear that CCS technologies may meet with strong
opposition, especially in regions where the applications have been tested or were intended
to be deployed on a long-term, permanent basis [9,10]. For example, in Germany and the
Netherlands, some projects to explore potential CO2 storage formations were abandoned
early, primarily due to massive opposition from local communities [11,12]. Since the early
2000s, the number of scientific publications on the acceptance of CCS has continuously
increased (see also Section 3). The perception and acceptance of CCS is strongly dependent
on the respective country [13] and due to the low level of knowledge about CCS [14,15], it
remains difficult to make valid predictions about how specific local attitudes towards CCS
might develop. g
p
This study is the first literature review to address the acceptance of industrial CCS
(iCCS). The objectives of this study are fourfold. First, it examines the extent to which
iCCS acceptance has already been empirically studied. Second, an analytical framework is
proposed to systematically review the existing literature. Third, factors that influence iCCS
acceptance are identified and discussed based on the review. Fourth, the results on the
acceptance of iCCS are compared with the acceptance of CCS in the context of fossil-fired
power plants. The assumption is that the attitude of society towards iCCS differs from
the attitude towards CCS along individual process steps and value chains. In this regard,
first scientific findings are emerging [16,17]. It is unclear in which direction these attitude
differences tend. 1. Introduction This study’s results should not only contribute to the scientific discussion and further
development of the research field, but also hopefully feed into the ongoing practical iCCS
discourse in industry and politics. At the international level, there are already associations
of industry players testing different technical use cases for iCCS in the form of pilot projects,
for example the European Cement Research Academy (ECRA). In some industrial processes,
the capture of CO2 emissions is already practiced today, and currently the first projects are
underway worldwide in different sectors, such as chemicals (Illinois Industrial), iron and
steel (Abu Dhabi Phase 1), and hydrogen (QUEST) [18]. The results of this literature review
should also provide indications of possible communication and empowerment needs on
the part of the general public and at the same time enable the more technology-based
scientific disciplines to place their developments on iCCS in a broader societal context. In order to be able to better classify the present analysis, the technological component
of the research object should first be explained in more detail. For a better understanding
of this, Renn’s classification [19] of the three areas of technology and their acceptance
parameters is helpful. He distinguishes between (1) products—everyday and leisure
technology; (2) technology in working life; and (3) external, large-scale and risky technology. The three technology areas differ in terms of their acceptance testing criteria. In the case of
current acceptance research on carbon capture and usage (CCU), for example, the focus
is often on the concrete evaluation of an end product, which can often be explained in
terms of buying or not buying, manageability, long-term durability or direct physical risks
(although the research approach here is also broader, for example [20–22]). In the context of
the present analysis, all scientific publications dealing with acceptance research on concrete
end products (e.g., mattresses, fuels) of CCU technologies were explicitly excluded. This
also appears consistent with [23], who clarify that CO2 utilization is often compared and
contrasted with CCS; however, they are two different technology pathways so it is necessary Sustainability 2021, 13, 12278 3 of 29 to address and evaluate these technologies separately. Since the subject of the present
analysis is the broader society, technology area 2, which deals with technology in the
workplace and thus targets “employees”, can also be excluded. 1. Introduction Following the exclusion
principle, only studies dealing with iCCS as an external, large-scale and risky technology
(area 3) were analyzed here. For this technology area, the test criteria of acceptability are,
for example, societal interests, rights, responsibilities, and legitimacy issues. The focus
of this review is therefore on technology pathways that capture CO2 on a large scale and
transport it for further purposes without further differentiating whether and how the CO2
is further used. This paper is structured as follows. First, Section 2 presents the selection of articles an-
alyzed, the methodological approach and the acceptance factors for CCS already identified
in the scientific literature, which are also used here as analysis dimensions. The results of
the content analysis are explained in detail in Section 3. In the Discussion (Section 4), we
present which of the identified acceptance factors for iCCS can be considered crucial for
the further development of iCCS and which scientific implications the results induce. The
conclusions in Section 5 illustrate some rough propositions for relevant groups of actors
dealing with issues of societal acceptance on iCCS in the future. 2. Materials, Methods and Acceptance Factors In order to assess the state of scientific research in the field of acceptance of industrial
CCS, a content analysis of scientific articles was conducted. Only articles published in
English between 2012 up to and including the end of 2020 were included. This time period
was chosen because, to the best of the author’s knowledge, no articles were published before
2012 that approached this topic. Thus, the chosen period of analysis seemed sufficient
to generate as complete an overview as possible of the state of the scientific literature on
this topic. •
public opinion. Using a combination of search terms, between 4099 (maximum at sciencedirect.com)
and 16,900 (maximum at scholar.google.com) articles were identified in the two online
databases. Only articles that explicitly address the topic of industrial CCS were to be
included (see Section 1 for narrowing criteria). For further identification of these articles
from the existing material, the so-called PRISMA criteria were followed [27]. Based on this
procedure, a complete search strategy for one of the databases used is presented below. The presentation is intended to create the prerequisite for the best possible reproducibility
of the search. The search strategy described here as an example refers to the online database
scholar.google.com. As previously described, the initial selection was made according
to the search terms presented above. With the search term “carbon capture industry ac-
ceptance”, approximately 16,900 articles were identified on 16 January 2021 (initial access
on 8 November 2020). In advance, the search of the articles was restricted to the years
from 2012 to 2020 inclusive in the menu under “select period”. Subsequently, the search
result was sorted by relevance (an option offered by the online database in the menu). The
individual short descriptions of the list of results on the homepage were read (not clicked
on) and checked to see if all individual search terms were included in the respective text
descriptions. This was an indication that all search terms were actually included in the
respective target article. In addition, it was checked whether the keywords appeared in
the desired context. If, for example, the term “industry” was linked to “coal industry”
and the title also indicated that the article was exclusively about CCS as a low-carbon
technology for energy generation, the article was excluded from further analysis. The
matches identified in this way were further checked for accuracy of fit by reading the
respective abstract or, if this did not appear to be sufficient for assessing accuracy of fit,
the conclusions. All hits identified in this way were then included in the pool for further analysis. Dur-
ing the course of the search, it became apparent that after approximately the fourth to fifth
page of results on the homepage, the articles listed no longer appeared relevant for the anal-
ysis due to missing keywords in the short text. Additional tools from scholar.google.com
were used to further identify relevant articles. 2.1. Selection of Articles Articles were identified using two online databases. First, the online database of
the publisher Elsevier (sciencedirect.com), a full-text database with an inventory of more
than 16 million articles and book chapters [24]. Although documents from other sci-
entific publishers are not included, Elsevier is one of the top 5 publishers in the world
with over 2000 journals published [25]. Second, the online database was used through
scholar.google.com. Google’s search engine presents only scientific literature; that is, books
or papers from professional journals [26]. Using these two most popular online databases,
it was possible to generate the largest possible proportion of scientific literature on the
topic of iCCS acceptance. Only scientific papers, book and conference contributions that could be generated
by keyword searches via the two online databases were included in the analysis. In
addition, one master’s thesis was evaluated that was identified via the online database
scholar.google.com and appeared to be relevant. No other dissertations or master’s or
bachelor’s theses were systematically searched for. Items were identified from November 2020 to 16 January 2021. The following search
terms were used to select the technology: •
carbon capture and storage;
•
carbon capture;
•
CCS; •
carbon capture and storage industry; •
carbon capture industry; •
CCS industry. The technical search terms were each combined with the following acceptance-related terms: The technical search terms were each combined with the following acceptance related terms:
acceptance;
b l •
acceptance; •
acceptability; •
perceptions; 4 of 29 Sustainability 2021, 13, 12278 •
attitudes; •
attitudes; •
public opinion. The option “cited by” lists all articles in
which the original hit was cited. A check of these articles was performed according to
the criteria already mentioned. The option “related articles” was also used. Using these
options, few additional articles could be identified. In addition, an “alert” was created,
which was used to automatically notify the author via email when new articles with the
given keywords appeared. This option appeared valuable in generating articles that did
not appear until the end of the analysis period. To ensure that all articles published by the
end of 2020 were identified, a final search query took place in mid-January 2021. The search
query at sciencedirect.com followed the same procedure and selection criteria. Beyond the
use of the two online databases, a few articles were identified via the references or sources
of the articles already identified and read in the course of the evaluation and included in
the analysis pool. Using these procedures, a total of 67 articles were identified and included
in the closer analysis. y
All 67 articles were then read completely. Of these, 42 articles were excluded. There
were two main reasons for articles to be excluded: •
Some articles only hinted at possible acceptance conditions for iCCS in their conclu-
sions. A presentation of these references to acceptance seemed mostly comprehensible,
but since they could not be sufficiently derived empirically from the study results, the
articles were not considered for further analysis. •
Other articles, as part of their methodological approach, focused only on the use of
CO2 (CCU) and did not differentiate by source (industrial capture or capture in the
context of electricity generation). Sustainability 2021, 13, 12278 5 of 29 Ultimately, 25 articles met the criteria to be included. It can be assumed that a large
part of the relevant literature was identified. 2.3. Acceptance Factors from the Field of CCS A wealth of individual studies, results, and initial overview studies are available on the
perception, attitude, and acceptance of CCS [29,30]. The first studies on the subject appeared
from 2002 [31–33]. In the literature up to 2015, publications on the acceptance of CCS focus
mainly on the use of the technology in the context of fossil power generation. Therefore, a
considerable number of factors determining the acceptance of CCS have been proposed,
many of which are commonly used to explain the acceptance of new technologies. There is
not a consensus on the one model best suited to predict CCS or technology acceptance [29],
although there are publications that present a technology acceptance framework [34] or
provide a model approach for selected factors [20,35,36]. Most studies, as mentioned,
examine the determining factors along specific research questions that can be categorized
into some thematic groups. These groups of topics mainly include (a) general acceptance
analyses “of the general public” in one country or in several countries; (b) analyses of
real-life-projects across different groups of actors, including the local society; (c) analyses
on communication and participation of CCS; and (d) analyses on specific process steps of
CCS, especially storage. In recent years, since 2015, more studies have been added on the
topic of CCU [20–23,37–41], which can be assigned to the abovementioned group of topics
and perhaps also represent a research unit in their own right (cf. chapter 1). However,
these factors have predominantly become established and are repeatedly used as a starting
point for new research studies and questions. Additionally, for the analysis of the articles
identified here for the topic area of industrial CCS, analysis dimensions were generated on
the basis of the acceptance factors just mentioned or the state of science (cf. Table 1, here
especially the factors from 1 to 8) (a similar set of influencing factors can also be found in
the acceptance research on the energy transition [42]). After the initial review of the articles
(relevance check), additional dimensions that seemed useful for analyzing the acceptance
of industrial CCS were added (compare factors 9 to 11). Table 1. Analysis dimensions of iCCS acceptance within the framework of the review. No
Potential Acceptance Factors
Explanation
Source 1
1
Perceived benefits
What personal/societal benefits are associated with
iCCS? (social benefits include environmental benefits)
[13,16,43–45]
2
Perceived risks
What personal/societal benefits are associated with
iCCS (including possible costs)? 2.2. Methodical Approach A qualitative content analysis of 25 articles was carried out using the MAXQDA
software. The software allows qualitative data and text analyses and is internationally
established in the field of science. For content analysis, a deductive category system was
developed (referred to as “analysis dimensions” in the following). It was derived from
the previous state of attitude and acceptance research on CCS. During the coding process,
some of the analysis dimensions were adapted and the possibility was left open to induc-
tively generate new dimensions, in accordance with the approach of [28]. The individual
dimensions or acceptance factors are discussed in more detail in the following subsection. 2.3. Acceptance Factors from the Field of CCS Moreover,
the assignment of sources is not exclusive because the respective studies often explored several categories of analysis. In this respect,
relevant sources were also assigned to more than one analysis category. In the following, the results of the evaluated articles are presented along the acceptance
factors described in Table 1. In addition to a presentation of the characteristic features,
such as methodology used, year of publication and technology path, the analysis clarifies
which influencing factors were assumed and investigated to explain the acceptance of
industrial CCS. In Section 4 (Discussion), these results are then reflected on and classified
in the context of the entire acceptance research on CCS so that first insights can be gained
on whether the acceptance factors on iCCS differ from the previous ones, in which areas
they differ, if any, and whether new factors have been added. 2.3. Acceptance Factors from the Field of CCS [13,16,31,44]
3
Values/attitudes
Can certain patterns of attitudes be identified that
have an influence on the acceptance of iCCS? [34,44,46]
4
Regional factors
What contribution do regional factors make to the
evaluation of iCCS technology? For example, are
citizens’ previous experiences with potential iCCS
companies or local storage options decisive? [11,12,47,48] Table 1. Analysis dimensions of iCCS acceptance within the framework of the review. 6 of 29 Sustainability 2021, 13, 12278 Table 1. Cont. No
Potential Acceptance Factors
Explanation
Source 1
5
Trust
How important is trust in iCCS actors for acceptance? What are the reasons for a lack of trust? [10,41,49–51]
6
Knowledge/awareness
How does the level of knowledge about iCCS
influence the evaluation of the technology? Are initial
perceptions of iCCS also important for acceptance? [52,53]
7
Communication/participation
What is the need for participatory
instruments/communication concepts for the
implementation of iCCS? Which communication strategy do companies pursue
for marketing/which actors do they involve? [54–58]
8
Socio-demographic factors
Can different socio-demographic factors induce
distinguished iCCS perceptions? [44,47,59,60]
9
Perceived differences to iCCS
in the power plant sector
Are there significant differences between the
acceptance of CCS in the power plant sector and for
industrial applications? [16,17,41,61–63]
10
Evaluation according to
process step
How is the use of iCCS evaluated along the value
chain stages (from investment to capture/transport to
CO2 storage and possible reuse)? How is iCCS assessed in the context of other carbon
abatement technologies and pathways? [14,17,41,64]
11
Regulatory/political aspects
How can a lack of regulatory frameworks, political
support and unresolved/complex approval
procedures influence iCCS acceptance? [14,65–67]
1 It should be noted that the sources cited in the table are only a small excerpt of possible sources that have dealt with the topic. A
comprehensive presentation of studies that have produced results on the respective dimensions of analysis is not intended here. Moreover,
the assignment of sources is not exclusive because the respective studies often explored several categories of analysis. In this respect,
relevant sources were also assigned to more than one analysis category. Table 1. Cont. Table 1. Cont. 1 It should be noted that the sources cited in the table are only a small excerpt of possible sources that have dealt with the topic. A
comprehensive presentation of studies that have produced results on the respective dimensions of analysis is not intended here. 3.1. Characteristics of the Analyzed Articles To place the iCCS publications in the overall context of all publications on the topic
of CCS acceptance, it should be mentioned in advance that until circa 2014 the number of
scientific publications on the acceptance of CCS increased steadily [29]. Between 2015 and
around 2018, the number of publications on the topic of CCS acceptance then remained at
a lower level than in the years between 2010 and 2014 [30]. Up to this point, publications
on the acceptability of CCS focused on the use of the technology in the context of fossil
fuel power generation. Triggered by the Paris Agreement 2015 [2], which highlighted the
urgency of limiting global warming to as close to 1.5 ◦C as possible, as well as a number
of other publications [1,3–5], as described in Section 1, the discussion about CCS has
continuously broadened and has more often focused on technology pathways that are not
directly related to fossil energy production. Since then, there has also been an increasing
number of scientific publications dealing with the acceptance of different technology paths
of CCS. Sustainability 2021, 13, 12278 7 of 29 The articles analyzed here were published between 2012 and 2020. Table 2 illustrates
the year of publication of the articles in combination with the selected technology path. The articles analyzed here were published between 2012 and 2020. Table 2 illustrates
the year of publication of the articles in combination with the selected technology path. Table 2. Theme clusters of iCCS acceptance in combination with year of publication [13–17,30,41,61–78]. Technology Path
2012–2015
2016
2017
2018
2019
2020
2021 1
iCCS without further
specification
Haug et al. [64], Broecks
et al. [63]
Pihkola et al. [69]
Xenias et al. [68],
Kashintseva et al. [67], Ilinova et al. [70], Thomas et al. [71], van Os [72]
Tcvetkov
et al. [30],
Whitmarsh
et al. [13],
Serdoner [73]
Swennenhuis
et al. [65],
Boomsma
et al. [74]
Evaluation of different
technology pathways
(variation of source,
transport, storage)
De
Best-Waldhober
et al. [17],
Wallquist et al. [16], Dütschke
et al. [61]
Offermann-
van Heek
et al. [41]
iCCS with focus on
CO2-storage
Gough et al. [14]
iCCS as low carbon
technology for
energy-intensive
industry (cement, steel)
Aursland
et al. [66]
Williams
et al. [62]
Bioenergy with CCS
(BECCS)
Kojo et al. [75]
Haikola et al. [76]
Rodriguez
et al. [77]
iCCS with reference to
hydrogen applications
Alcalde et al. 3.1. Characteristics of the Analyzed Articles These
studies are often linked to specific project proposals, for example the ALIGN project (It is
expected that further scientific publications on the acceptance of iCCUS will be published
in 2021 from research projects that have been and will be funded within the framework of
Horizon 2020 of the European Commission, such as the ALIGN-CCUS and STRATEGY
CCUS projects) [74], and concentrate on regions with industrial clusters that are significant
geologically and in terms of their industrial structure with regard to the development of
iCCS and are already being scientifically researched in part (compare lines 4 to 6, Table 2). The analyzed articles on iCCS acceptance come from a total of 15 different countries,
of which European countries represented 13—an overwhelming majority. The following
European countries were involved in the preparation of the articles: United Kingdom = 7;
The Netherlands and Germany = 4 each; Norway = 3; Finland and Sweden = 2 each; and
Austria, Belgium, Lithuania, Portugal, Romania, Spain and Switzerland with one article
each. Five of the European articles involved more than one country. As mentioned at the
beginning, previous studies on the acceptance of CCS have made clear that protests and To address this complexity, four of the studies provided their participants with a
selection of different realistic CCS technology pathways to evaluate (compare row 2 Table 2),
which at least allowed for a more differentiated view according to different CO2 sources,
such as the evaluation of CO2 capture in a chemical plant [41]. Since 2019, there has
been an increase in acceptance studies investigating the impact of specific industrial
CCS applications, such as from cement or steel plants or for the BECCS sector. These
studies are often linked to specific project proposals, for example the ALIGN project (It is
expected that further scientific publications on the acceptance of iCCUS will be published
in 2021 from research projects that have been and will be funded within the framework of
Horizon 2020 of the European Commission, such as the ALIGN-CCUS and STRATEGY
CCUS projects) [74], and concentrate on regions with industrial clusters that are significant
geologically and in terms of their industrial structure with regard to the development of
iCCS and are already being scientifically researched in part (compare lines 4 to 6, Table 2). The analyzed articles on iCCS acceptance come from a total of 15 different countries,
of which European countries represented 13—an overwhelming majority. 3.1. Characteristics of the Analyzed Articles [78]
Glanz et al. [15]
Total
2/1
2
2
6
6
4
2
1 These two articles have already been published in mid-January 2021. Due to their relevance, the author decided to include them before
completing this article at the end of January. No other articles from 2021 were included in the analysis. Table 2. Theme clusters of iCCS acceptance in combination with year of publication [13–17,30,41,61–78]. s have already been published in mid-January 2021. Due to their relevance, the author decided to include them before
ticle at the end of January. No other articles from 2021 were included in the analysis. dy been published in mid-January 2021. Due to their relevance, the author decided to include them before
nd of January. No other articles from 2021 were included in the analysis. 1 These two articles have already been published in mid-January 2021. Due to their relevance, the author decided to in
completing this article at the end of January. No other articles from 2021 were included in the analysis. As shown in Table 2, by the end of 2020, most articles on iCCS were published in 2018
and 2019 (n = 6 in each year). A slight majority of the 25 articles (n = 13) use the terminology
“industrial CCS” (compare row 1 Table 2), but do not further explain which technological
concept of iCCS technologies is involved in the definition or within the operationalizations. This is not surprising, as the technological applications of iCCS are highly complex along
the process steps and the different value chains that may be involved. the process steps and the different value chains that may be involved. To address this complexity, four of the studies provided their participants with a
selection of different realistic CCS technology pathways to evaluate (compare row 2 Table 2),
which at least allowed for a more differentiated view according to different CO2 sources,
such as the evaluation of CO2 capture in a chemical plant [41]. Since 2019, there has
been an increase in acceptance studies investigating the impact of specific industrial
CCS applications, such as from cement or steel plants or for the BECCS sector. 3.1. Characteristics of the Analyzed Articles The following
European countries were involved in the preparation of the articles: United Kingdom = 7;
The Netherlands and Germany = 4 each; Norway = 3; Finland and Sweden = 2 each; and
Austria, Belgium, Lithuania, Portugal, Romania, Spain and Switzerland with one article
each. Five of the European articles involved more than one country. As mentioned at the
beginning, previous studies on the acceptance of CCS have made clear that protests and Sustainability 2021, 13, 12278 8 of 29 risk perceptions on CCS have formed along exploration plans and projects, especially in
Europe—particularly in the Netherlands [12] and Germany [11]. risk perceptions on CCS have formed along exploration plans and projects, especially in
Europe—particularly in the Netherlands [12] and Germany [11]. In this respect, if an iCCS strategy is to be pursued on the political level in the long
term, these countries seem to have a particular interest in predicting future developments
regarding the acceptance of iCCS. For Great Britain, the situation is similar; here, according
to [79], 17.2% would “probably not use” or “definitely not use” CCS technologies according
to a representative survey. A further three articles come from Russia and another one from
the United States of America. According to [30], Russia has a special interest in the use
of enhanced oil recovery (EOR) technology, which requires a lot of CO2, and therefore is
considering CCS as a future option to develop this technology. g
gy
The relevant articles on the acceptance of iCCS were published in a wide range of
journals. In total, the 25 articles come from 15 different journals. The International Journal
of Green-house Gas Control accounts for 8 articles—by far the most. This is followed by the
journals Energy Procedia and Journal of Cleaner Production, with 2 publications each on the
topic. One of the analyzed articles is a Master’s thesis, which was written at the University
of Graz and cannot be assigned to any journal [73]. Different theoretical concepts and approaches were used in the articles included. Twelve of the analyzed articles on iCCS acceptance do not mention any theoretical concepts. The concept of Wüstenhagen [80] to classify three different dimensions of social acceptance
is mentioned and applied in two articles. 3.1. Characteristics of the Analyzed Articles Studies that focus their analysis more on the
regional or project level often include actor and communication-related approaches, such
as the theory of public engagement in [68], the social licence to operate (SLO) in [14,74], the
end-to-end stakeholders involvement approach in [67], the concept of procedural fairness
in [62], the concept of media agenda-setting in [75], the stakeholder theory for management
in [70] and the cognitive theory of shifting coalitions in [73]. In addition, the articles mention social-psychological concepts that illuminate social
behavior even more against the background of cultural aspects and certain values, such
as the theory of planned behavior in [30] and, in the context of the Master’s thesis, the
concept of the Ethical landscape of CCS, the theory of worldviews and the cultural theory
to specify belief systems in [73]. Two of the analyzed articles reflect their findings on iCCS
acceptance to the whole debate on energy system transformation using the just transition
approach [65,78] or the multidimensional research concept as in [15]. A complete table of the analyzed articles with the categories “first author”, “year of
publication”, “method(s) used”, “country”, “iCCS-related technology”, and “important
statement in relation to iCCS” is provided in the Appendix A (Table A1: Overview of the
analyzed articles). 3.2. Key Findings along the Dimensions of Analysis as well as Additional Insights In the following, the main results of the analyzed articles are presented along the
analysis dimensions shown in Table 1. 3.2.1. Perceived Benefits However, not only is the preservation or renewal of existing economic structures
identified as a benefit of iCCS, but the technologies should also serve to promote and
profile municipalities and regions as environmental and technological leaders, ultimately
to develop new industrial activities [64]. In this context, there is also talk of a potential
image boost for iCCS industries and regions [62]. For example, refs. [75,77] argue the
relevance of developing and deploying BECCS, a technology pathway discussed as an
advantage for forest-rich countries such as Finland [75] and which holds the potential to
establish itself as a “first mover” [77]. Without BECCS it would be a challenge to meet
emission targets, but with BECCS Finland could gain advantages by saving and trading
emission rights [75] (see also Section 3.2.11). g
(
)
Regarding the impact of environmental effects (reduction of CO2 emissions, slowing
of climate change) and their classification as a benefit for the acceptance of iCCS, there
are different results in the analyzed studies. Some study results suggest that attributing
the benefits of iCCS to improving the regional and global environmental situation can
create an advantage for the perception of acceptance [15,30,70,75]. Similarly, the results of a
representative study in Canada, the USA, the UK, the NL, and Norway illustrate that iCCS
can help mitigate climate change and support the economy according to the respondents
in [13], which could be interpreted as a benefit for the technology. However, the same study
also highlighted that framing CCS as dealing with ‘waste’ (in conjunction with CO2 reuse)
seems to be more persuasive in encouraging support than framing it in terms of climate or
economic benefits. The authors of [74] critically note that the siting of new or expanded
iCCS facilities is more likely to be associated with national and international benefits,
for example achieving energy and climate goals and economic revenues (on this also
see [70]), and that the apparent benefit to local communities may turn out to be a potential
burden, for example through subjectively perceived risks. Such a perceived imbalance
between (negative) local impacts and national or global benefits would pose a challenge
when it comes to public response to iCCS technologies [74]. 3.2.1. Perceived Benefits The results of the studies analyzed have identified some benefits that appear to be
associated with the use of iCCS and thus may have a positive impact on social acceptance. These benefits include the possibility of creating local and national value through iCCS
projects [64]. p
j
For example, the municipality of Porsgrunn in Norway considers iCCS important in
legitimizing industry in the region and thus sustaining related jobs in the long term [64]. Additionally, ref. [71] sum up that the potential of iCCS can protect and rejuvenate historical
employment patterns and this opportunity makes iCCS an attractive option for an area. This is also important to counteract the out-migration of the local population that threatens
to occur if established industries go away [64]. Beyond protecting existing jobs, ref. [71]
make the argument that providing infrastructure for iCCS can also create additional
employment opportunities in the region. Consistent with this, communities hosting CCS Sustainability 2021, 13, 12278 9 of 29 projects would benefit economically from the jobs and revenue that the industry would
provide [13]. projects would benefit economically from the jobs and revenue that the industry would
provide [13]. p
In addition, regional clusters containing multiple capture projects can benefit from
shared CO2 transport and storage infrastructure to maximize value, share investment deci-
sions and operating costs, and thus reduce development costs [78]. Thus, ref. [64] postulate
benefits from mergers of larger regional clusters for iCCS (across national borders). For
example, in their study, they identified the notional “Skagerrak Cluster” for the countries
of Norway, Sweden, and Denmark, which identifies some key geographic features that
have good conditions for establishing iCCS technology (similar to the northeast region
of Scotland). The advantages come from the possibility of storing the CO2 offshore, with
emission sources relatively close to the sea. According to [64], the relevance of looking
more closely at the Skagerrak cluster provides valuable input for evaluating acceptance
and communication challenges for other iCCS clusters in the Nordic region. These benefits
of iCCS overall can be linked to increasing the economic viability of both the technology
itself and the region in question, these are benefits that [30,70] also highlight in their study. 3.2.2. Perceived Risks According to the studies analyzed, the use of iCCS technologies is associated with
various societal risks that can have a negative impact on acceptance. These include per-
ceived risks at the local level, for subsequent generations and for ecological and economic
systems, but also risks for making political decisions that do not contribute to improving
climate protection in the long term. The most frequently mentioned risk perceptions in the
studies relate to negative health impacts, especially for people living near CO2 storage and
transport infrastructure [62]. The local impacts of iCCS are particularly addressed here [68], and with it the accom-
panying sense of unfair treatment of those who suffer disadvantages [30,74]. It is believed
that iCCS could become locally entrenched as a “risky technology” in the perception of local
and regional populations [15], especially if CO2 storage occurs on land [77]. Hazards are
expected from possible CO2 leakage and seismic risks [15,75,77]. The perception would not
improve even if already existing infrastructure were used [15]. The same applies to the CO2
transport route; here, too, leakages and unforeseen risks are feared by the population [15]. In addition, several stakeholders in Germany expected so-called spillover effects, which
occur when already existing rejections of CO pipelines are transferred to CO2 pipelines on
the grounds that these transport options are not sufficiently differentiated in society [15]. g
p
p
y
y
In this context, the fear of a lack of acceptance of responsibility on the part of politics
and industry [71,77] and the societal desire to avoid uncertainties are mentioned [30],
especially when it comes to long-term monitoring of CO2 infrastructure, which is primarily
intended to ensure the protection of future generations [71,73]. In addition to health risks
from the use of iCCS, ecological risks were also mentioned in the analyzed articles [15,75,76],
which can have an unfavorable impact on acceptance. For example, interventions in the
ecological system through the construction of new CO2 infrastructure can permanently
endanger the environment [15]. In addition, one study expressed fears about the possible
effects of stored CO2 in the seabed [73], which could, for example, affect the fauna and
flora of nearby coastal regions and lead to catastrophic consequences there [71]. At the
same time, the use of iCCS technologies was interpreted as a standstill for other climate
protection measures in industry that would lead to lock-in effects of unsustainable corporate
practices [73]. 3.2.1. Perceived Benefits Hence, currently there is no
consistent evidence from the scientific community as to whether iCCS is perceived as a
mitigation option for CO2, and thus as a climate technology, and whether this has a positive
or negative effect on the perception of the benefits of the technology. Moreover, such a
perception is certainly also dependent on many regional factors. For completeness, here are the five main benefits of CCS industrial projects accord-
ing to [70]: (1) reduction of negative impacts on the environment, (2) contribution to
socio-economic development of regions and territories, (3) attractive direction for socially
responsible investments, (4) support for sustainable development of companies involved
in CCS projects, (5) use of CO2 for purposes such as improving oil recovery by oil and gas
companies, increasing energy efficiency of industrial companies. Sustainability 2021, 13, 12278 10 of 29 10 of 29 The analysis of perceived benefits gives the impression, as also indicated by [30] and
previous studies on the benefits and risks of CCS, that benefit perception may exert a
stronger influence on iCCS acceptance than risk perception. 3.2.3. Preferences/Values In the context of the studies analyzed, a variety of values and attitudes were explained
that can have an influence on the acceptance of iCCS. These broadly include cultural
identity, the closely related moral concepts of a society, environmental awareness, the per-
ceived influence of iCCS on people’s living conditions and attitudes toward technological
developments and industry. According to the study by [13], nationality is the strongest predictor of support for
iCCS. Closely related to nationality is the cultural identity of a country. Thus, a study
explained that compensation services to communities [74] must take into account the
cultural as well as the social context [14,30,62]. Here, it is especially important that sacred
values such as human safety are not mixed against a secular value, for example, by
accommodating a hazardous facility in exchange for monetary compensation [74]. Certain
normative ideas and moral values are also obviously advantageous for the development
of a positive attitude towards iCCS [63,76]. Insofar as the use of iCCS can compensate
for possible inequalities in society [65], for example, by allowing regions with a high
proportion of energy-intensive industries to hold on to their economies to some extent or
to operate them in a climate-friendly manner through iCCS, this represents an advantage
for the perception of iCCS [64]. However, such perspectives do not go hand in hand with
the moral notion that iCCS is interpreted as an intrusion into the subsurface “wilderness”
or that BECCS is morally indefensible due to the still unclear availability of biomass, as
stated in [71]. A view that, according to [71], occurs among those with strongly ecological
values. According to [71], iCCS can only contribute to justice in society where a common
understanding of cultural, natural and socio-economic systems prevails. g
y
p
The influence of environmental awareness on the acceptance of iCCS is still evaluated
very differently. Thus, ref. [13] clarify that a high environmental awareness can lead to a
low acceptance of iCCS as the technology is seen as less important for coping with climate
change than other technological options [63]. Whereas BECCS technologies seem to get
a better rating in [71] compared to CO2 capture from further industrial processes (here
certain views of environmental awareness do not seem to be in conflict with the moral
risks of BECCS mentioned above). 3.2.2. Perceived Risks However, the results on the perception of iCCS technologies are partly
contradictory; on the other hand, there is apparently the concern that without their use,
no adequate emission reductions for the climate can be achieved by energy-intensive
industries [62] (which can ultimately be seen as an advantage for iCCS). y
g
In addition to these societal risks, the studies also mentioned some personal risks that
may be decisive with regard to the perception of iCCS. These include, in particular, the
previously mentioned perceived health risks, which could lead to a strong rejection of iCCS
technologies, especially on the part of the local population [13,30,71]. Personal risks may
also be perceived in conjunction with the economic factors of iCCS. For example, the results
of the analyzed studies illustrate that the factor of employment can be perceived as both a
personal risk and a benefit [14,65] for people in a region in the context of iCCS. For example,
one study expressed concerns that iCCS may impose costs that are then offset by, for
example, lower employment levels in iCCS operations. On the other hand, the introduction
of the technologies could create new areas of work and if steps were taken to retrain and
employ industrial workers within the iCCS sector, this would be a benefit [71]. However,
there has been an equal concern that there may be inflation of products through use with
iCCS and in the long run this effect will contribute to industrial companies becoming
uncompetitive in the global market and may lead to local plant closures [65]. 11 of 29 Sustainability 2021, 13, 12278 11 of 29 3.2.4. Regional Factors In this section, we will focus on the factors that can exclusively determine the regional
characteristics and conditions for the development of iCCS acceptance (independent of
other factors such as trust, knowledge, and communication, which can also influence
the regional perception of iCCS). These factors on regional specificity include the specific
history of an area and the regional perception of iCCS technologies in the context of other
developments, such as the economic activities and geological conditions of the region. The results of the studies analyzed suggest that despite the processes of deindustrial-
ization in advanced capitalist economies, deeply rooted cultural narratives of industrial
modernity and manufacturing employment remain powerful markers of identity and social
progress [64,71]. In regions with an industrial heritage, where the local public feels con-
nected to industry, this identity is particularly high [74]. Regional populations appreciate
it when industrial actors inform them and involve them in their activities and plans to
give them a sense of belonging and identity [66,74]. It is becoming apparent that people
in such regions are concerned that these industries remain fully intact and are becoming
sustainable [13,62]. Ref. [14] contribute to this thesis, for example, with the study of Teesside (UK). Teesside
is a conurbation with a strong industrial base that residents rely on. Ref. [74] also assume
that people in such regions are more positive about iCCS development than people who
are less rooted in their industrial heritage. For example [66], describes that the Norcem
industry began producing cement as early as 1919 and quickly became a major player in
the economic life of the region. Ref. [64] emphasize the aspect of habituation. If people are
used to industrial activities, especially when industry has operated in the area for decades,
this has a positive effect on trust towards local industry and politics. For example, residents
in northern regions are also accustomed to transporting products that are considered more
dangerous than CO2, such as ammonia. Ref. [13] assume that areas where iCCS plants are likely to be built are typically those
locations where (analogous) industry already exists. Subjective familiarity with such an
industry could also serve to reduce the perceived risks associated with new infrastructure,
leading to greater acceptance (or tolerance) of iCCS within regions. 3.2.3. Preferences/Values Either way, BECCS is obviously viewed positively
here because it is more likely to be associated with natural processes through the use of
biomass [16]. However, if iCCS technologies are placed in the larger context of addressing
climate change, where the technologies are embedded as part of an overall strategy to
reduce CO2, their perception as an environmentally conscious technology may change
if necessary [13,65]. Here, the urgency to address climate change postulated in recent
years seems to have become a helpful vehicle for improving society’s perception of iCCS
technologies [63]. Another step towards valuing iCCS as an environmental technology
focuses on the perception of CO2 as a significant resource [64] rather than a waste product
(see Section 3.2.1) or iCCS as a socially desired argument to support energy-intensive
industries in the context of political decarbonization intentions [53]. It remains open whether, far from being environmentally conscious, people can
develop a positive perception of iCCS out of a certain technological affinity. The authors
of [30] present a study in which people with a positive attitude toward gas infrastructure
development are more supportive of iCCS than people without this attitude. In addition
to environmental awareness and technological affinity, the perceived impact of iCCS on
people’s concrete living conditions is also likely to be significant in assessing acceptance [68]. For example, results from a focus group [71] illustrate people’s fears that a life based on
the renewable energy technology system may be very regimented and “robotic” and that
this development may negatively affect previously valued lifestyles. In light of these
considerations, the use of iCCS technologies is evaluated in a different context; in which
through them traditional ways of life can be maintained for longer, which is evaluated as
quite positive [70]. The authors of [13] also found in their study that people with energy-
intensive lifestyles were more likely to prefer iCCS than others because they too could
maintain their lifestyles while not being accused of promoting climate change. Sustainability 2021, 13, 12278 12 of 29 12 of 29 The general attitude of the population toward the industry could also be an indicator
for the future acceptance of iCCS. This is an aspect that will be discussed in more detail in
the following section, as it is very closely linked to questions of the regional affiliation of
the public. 3.2.5. Trust In almost all analyzed studies (n = 23), the topic “trust” was treated as a crucial
acceptance factor for iCCS. Ref. [74] conclude that research indicates that trust in developers
and other stakeholders is a critical factor influencing public response to a development such
as iCCS as a whole, as well as at the community level. Within the studies analyzed, the trust
factor is predominantly discussed in the context of regional processes and stakeholders on
iCCS. Some stakeholder groups enjoy more trust among the population than others. These
groups include in particular (environmental) non-governmental organizations (ENGOs)
and local stakeholders, for example politicians and investors, who are considered to
represent local and civic interests [15]. These groups of people are thus seen as having a
certain degree of integrality. Whereas [62] notes that in the context of a focus groups in
Wales (United Kingdom), a distrust of both a major steel producer and the government at
all levels was mentioned based on a lack of integrity and competence. According to [14],
perceptions of trust in key institutions depend on the track record of those institutions in
managing past industrial processes. Local authorities seem to have a special role to play here in developing a deeper
commitment, as they can act as facilitators for the deployment of iCCS [65]. The importance
of the position of the municipality towards CCS projects has been shown in previous studies. In Barendrecht in the Netherlands, the local government rejected a proposed CCS project
because they feared negative impacts on public health and a decline in property values [64]. Accordingly, it is important that the community, including the people who live there, feel
that the continued efforts of industry to build technology like iCCS is also directed toward
solutions to environmental challenges [64]. This is where community familiarity with
industry relevant to CCS implementation may also be important [64]. Moreover, ref. [13]
argues that subjective familiarity with such an industry may serve to reduce the perceived
risks associated with new infrastructure, leading to greater acceptance of iCCS within the
intended communities. At the same time, gaining public trust is an extremely lengthy and labor-intensive
process that is highly dependent on experience in the interaction between laypersons and
project stakeholders [30]. 3.2.4. Regional Factors This can also include industry engagement with
the local public, which is seen as the “key vehicle for achieving social license” by [81]. g g
p
y
•
Creation of interactional trust; in which all participants engage in a mutual dialogue
(in relation to communication, compare also Section 3.2.7); p
•
Establishing an institutionalized trust in which a lasting relationship with community
representatives is established, taking into account mutual interests. This dialogue also
includes the industry’s ongoing efforts to address environmental challenges, including
iCCS—see also [64]. In addition to the factors already mentioned, the studies identified further aspects
that may have an influence on the regional acceptance of iCCS; these include the specific
economic situation and the geological conditions of a region. These have already been
discussed in more detail in Section 3.2.1 on the perceived benefits of iCCS and will not be
repeated here. 3.2.4. Regional Factors Fundamentally, accord-
ing to [74], there is a need to understand local social realities, such as understanding what
a particular place means to the local public, as well as how iCCS technology can impact
this meaning at an early stage of the projects. However, refs. [15,30,67] also emphasize that past economic activities, for example,
when coal mines are present in the region or there have been incidents with health impacts
for local residents, can have a lasting negative effect on the implementation of new projects. For example, the explosion of a gas pipeline in Belgium in 2004 increased public concern
about the perceived reliability of CO2 transport [30] (see also [15] regarding the CO pipeline
in Section 3.2.2). Another crucial factor for the regional acceptance of iCCS seems to be the specific
perception of actors and issues related to a (possible) project. Ref. [74] suggests that this
debate is also in the literature on the so-called social license to operate (SLO): “SLO refers to
the informal permission granted to industry by the local community and wider society to
develop a technology; in the context of CCS, SLO has been recognized as very preliminary
and fragile”. The following factors are summarized for achieving an SLO by [74] and are
supplemented here by the results of other studies: •
Weighing the costs and benefits to the community, based on the particular characteris-
tics of the project (see also [13]). Here, the ability of iCCS to protect jobs was identified
as one of the key benefits. These benefits can be felt even more strongly for iCCS as it •
Weighing the costs and benefits to the community, based on the particular characteris-
tics of the project (see also [13]). Here, the ability of iCCS to protect jobs was identified
as one of the key benefits. These benefits can be felt even more strongly for iCCS as it Sustainability 2021, 13, 12278 13 of 29 13 of 29 both protects employment in existing industries and provides infrastructure that can
attract new investment and employment opportunities [13,66,71]; both protects employment in existing industries and provides infrastructure that can
attract new investment and employment opportunities [13,66,71]; •
Creation of socio-political legitimacy; that is, whether an industry and all other (in-
terest) groups act fairly, respect local lifestyles, and, in sum, the community plays a
role and is involved (see also [13]). 3.2.6. Knowledge/Awareness As expected, none of the studies analyzed provide any information on what the state
of public perception and knowledge of iCCS technologies is. However, the results of [13]
show that public awareness of CCS (without concreteness to iCCS) remains low (here for
Canada, the Netherlands, Norway, the UK and the US) and this result is also in line with
previous research. However, in deciding whether to accept or reject CCS, the general level
of knowledge and awareness plays an important role, as illustrated by the presentations
from Tcvetkov’s literature review on CCS [30]. Stakeholders interviewed by [15] in the
ELEGANCY project rate public knowledge about CCS as rather low and perceive that
iCCS technologies are not yet present in the current public discussion due to low market
penetration. The results of [61] in the context of an experiment suggest that iCCS is viewed
more positively by those who claim to have more knowledge about iCCS and that they are
also likely to show a higher interest in the technology. Additionally, ref. [41] found that
higher information levels can fundamentally change the evaluation of CO2 capture options
(for example air capture or from chemical plants). p
p
p
The study [64] emphasizes that the local population in Porsgrunn (Norway) is not
only used to industrial activities, but is also likely to have concrete experience with iCCS
activities. There is a sense that the local population is positive about the proactive approach
to managing CO2 emissions, and this assumes that there is some level of knowledge about
iCCS locally. Beyond this level of knowledge about iCCS, ref. [77] clarified that industries
also have an interest in iCCS technologies becoming more widely known. For example,
to market BECCS, public knowledge of low-carbon technologies is a possible positive
aspect. The reasoning is that customer demands for negative emissions make investment
decisions easier for industries because they can integrate iCCS technologies as part of
their sustainability strategy. According to [65], however, even key stakeholders such as
trade unions and environmental organizations lack evidence-based information on the
iCCS capabilities of carbon-intensive industries. Ref. [73] also assumes that environmental
organizations (related to Europe) lack the necessary resources to acquire knowledge about
different iCCS technology options in detail. This lack of capacity also contributes to the
apparent lack of official positions on issues such as iCCS until 2018 [73]. 3.2.5. Trust It is also important to avoid violating trust as much as possible, as
it can be difficult to rebuild and can also cause negative spillover effects on perceptions of
other technologies and projects [14]. Distrust can have an effect in different areas, on the one
hand with regard to the competence of the responsible persons (competence-based distrust),
especially when it comes to the implementation of a complex infrastructure project such as
iCCS technology [62]. On the other hand, distrust can also relate to procedural fairness in Sustainability 2021, 13, 12278 14 of 29 14 of 29 the participation process (integrity-based distrust [62]; compare also the comments on socio-
political legitimacy in Section 3.2.4). According to [74], without a more comprehensive
public involvement strategy, the question remains whether this is sufficient to build a sense
of trust towards the developer. 3.2.6. Knowledge/Awareness pp
p
Beyond just awareness and knowledge of iCCS, the studies address the need for
contextual knowledge. For example, ref. [72] suspects that there will be a more positive
perception of iCCS as people become more aware of their individual climate impacts. Thus, some of the stakeholders interviewed in the study of [15] also see a general lack of
societal acceptance regarding energy technologies and large-scale infrastructure, attributed
in part to a lack of knowledge. Perception of global warming issues, understanding of
the role of humans in this process, and developing an objective view of the prospects of
low-carbon technologies, including CCS, depend on the education of respondents [26,30]. Therefore, implementation of an educational strategy for sustainable development should
be considered, which starts at school and could be part of a national “green” policy. Ref. [71]
clarified in their study that with the level of knowledge about iCCS and the integration
of the technologies into a higher-level thematic context, the initially perceived assessment
of iCCS can change once again. If iCCS is initially interpreted as a potential threat to
natural systems, subsequent presentations and scenario discussions led to a gradual shift
in how participants interpreted iCCS. Similarly, ref. [62] clarifies that participants in two
focus groups on the Port Talbot steel mill development acquired contextual knowledge to
evaluate iCCS. For example, they express concerns that if iCCS makes steel more expensive,
the Welsh steel industry could lose out to foreign competitors who continue to produce
emissions-intensive steel at the lowest price. If nothing else, these findings illustrate Sustainability 2021, 13, 12278 15 of 29 15 of 29 that awareness of iCCS does not immediately predict public acceptance of a project [30]. Ref. [66] also note that regardless of the depth of their insight and knowledge, people
will acquire subjective perceptions about iCCS. Ref. [30] sees consolidating government,
industry and NGO efforts as one of the key challenges to improving public perceptions
of CCS. that awareness of iCCS does not immediately predict public acceptance of a project [30]. Ref. [66] also note that regardless of the depth of their insight and knowledge, people
will acquire subjective perceptions about iCCS. Ref. [30] sees consolidating government,
industry and NGO efforts as one of the key challenges to improving public perceptions
of CCS. 3.2.7. Communication/Participation The discussion of CCS communication and participation in the articles analyzed is
extensive and is therefore presented in the form of a table (Table 3). Ref. [68] suggests
that the CCS community is generally aware of the range of factors that influence public
engagement. Whether this range changes significantly for communication about iCCS
cannot be adequately answered using the available results. Ref. [74] illustrates that effective
public engagement will be key to successful iCCS implementation. With this comes the
need to further explore how to most effectively engage with the local public. w of the acceptance factor “communication/participation” of iCCS (who/what/how). Table 3. Overview of the acceptance factor “communication/participation” of iCCS (who/what/how). What should be communicated? iCCS narrative embedded in the overall context of sustainability
Urgency to combat climate change
Framing of iCCS as environmental technology (where there is no alternative)
Discussion of alternative technologies
Integration into norms and values of society
Costs in the context of the overall energy transition
Economic advantages and disadvantages
Set economic consequences in relation to ecological ones
Infrastructure challenges/use of existing infrastructure
Presentation of project experiences incl. risk analyses
Integration into current political context
Liabilities/standards/regulatory framework/securityRole of iCCS for global economy/international cooperation Who should communicate? Persons of trustPersons within the scope of their respective expertise
Qualified project team How to communicate? Develop an empowerment and communication strategy and plan
Take into account the main principles of public participation
Meaningful voice during decision-making processes
Establish continuity in communication
Fairness/greatest possible transparency/inclusion of all/neutral/clear/high quality
Creation of problem-oriented knowledge, e.g., FCDP
Include local needs and contexts/site characterization. Consider community compensation
Use of classic media, such as brochures, local media
Facilitate face to face exchange, e.g., local activities and events
Use of digital media
The chosen order of the factors does not represent a weighting. In this context, it seems important to mention again the aspect of [74], which empha-
sizes a certain flexibility in dealing with iCCS projects, as specific concerns and needs may
change over time in different regions. Here, regular adjustments of the implementation
strategy of iCCS projects have to be taken into account. Sustainability 2021, 13, 12278 16 of 29 16 of 29 3.2.9. Perceived Differences between CCS and iCCS In the following, the question is addressed whether significant differences between
the acceptance of CCS from fossil-fired power generation plants and the acceptance of iCCS
from industrial processes can be derived from the results of the analyzed studies. There
are a number of initial results on this, but they target different technology pathways and
are therefore hardly comparable. First, ref. [30] suggests that CCS technologies received
general support from respondents in a survey, but when it comes to specific options for
implementation, for example as part of gas and coal-fired power plants, initial public
preferences may be negated. Additionally, according to [71], focus group participants
articulate more positive visions for iCCS and BECCS than for coal CCS. They affirm
support for growth through iCCS in manufacturing industries, as this is highly desired by
society. Additionally, ref. [15] assume that iCCS will have higher social acceptance than CCS. Beyond this more economic aspect, ref. [68] represents the need to significantly broaden
the iCCS discussion to include heavy industry and processes outside of power generation. This was seen as necessary to counter the traditional arguments of environmental groups
that reject CCS because of its ability to re-generate electricity. In addition, initial studies
compare the acceptance of iCCS with the acceptance of gas-fired power plants. For example,
ref. [16] show in their experiment that BECCS plants receive higher approval than those
using conventional gas. Interestingly, as perceptions of BECCS improve, so does the
willingness of one’s community to accept CO2 storage. Ref. [17] also found that large-scale
plants converting gas to hydrogen (H2) with CCS tend to be viewed negatively by most
respondents. Basically, ref. [71] assumes that fossil CCS is considered unacceptable by the
local population, while other CCS options, like iCCS, remain feasible. 3.2.8. Socio-Demographic Factors 3.2.8. Socio-Demographic Factors The analysis of the influence of socio-demographic factors on the acceptance of iCCS
from the available studies does not reveal any meaningful trend. According to [67], for
example, the acceptance of iCCS among women is about three times higher than among
men (in selected European countries). Additionally, according to [13], men (as well as
older people and people with high incomes) showed lower support for iCCS (but only
after reading the message on CCS and possible lifestyle change). In contrast, ref. [30]
presents findings in which men show more tolerant perceptions of CCS risks when the
economic potential is present, while women are more concerned about safety. Additionally,
as mentioned earlier in the context of a country’s cultural identity (see Section 3.2.3),
nationality represents the strongest predictor of support for iCCS [13]. All other results on the influence of the socio-demographic factor do not explicitly
refer to iCCS technologies and therefore do not find any further explanation here. 3.2.10. Evaluation of iCCS for Different Process Steps In contrast to oxy-fuel technology,
post-combustion requires larger constructional measures and entails a visible and
significant change to the existing plant. Therefore, acceptance-relevant aspects may
occur due to construction sites and changes in the landscape [15]. g
p
•
Direct air capture (DAC): according to [41], capturing CO2 from ambient air is not an
accepted option among the public, especially when detailed information on efficiency
and energy requirements is available. •
CO2 capture from chemical plants: the results of a study by [41] show that providing
technically correct and comprehensible information has the potential to completely
revise previous negative opinions of study participants. The prerequisite is that it is
explained transparently that the capture of CO2 from a chemical plant is highly effi-
cient and has a lower environmental impact compared to other alternatives. Initially
negative reactions can thus be transformed into positive acceptance ratings. The following findings are available on the acceptance of the CO2 transport pro-
cess step: •
Rejection of CO2 pipelines: Respondents’ judgments in an experiment by [16] were
most influenced by the pipeline factor, to a lesser extent by the plant factor, and least
by the storage location factor (there are a variety of contrary results on this). However,
people seem unwilling to live near a pipeline (respondents from Switzerland), al-
though they would prefer a CO2 pipeline to a gas pipeline. Field testing of geological
storage in densely populated areas may therefore consider avoiding pipeline transport
to increase the likelihood of public acceptance [13]. •
Use of existing infrastructure: ref. [41] make clear in their study that CO2 transport
by truck and a mix of trucks and pipelines are not preferred by the participants. In particular, the negative ecological effects expected for the construction of new
infrastructure packages are mentioned here. Instead, it is recommended to examine the
potential of using the existing infrastructure for alternative fuel production. A further
step would even be the avoidance of CO2 transports by spatially linking CO2 capture
and fuel production—an option that should be examined in terms of acceptance. 3.2.10. Evaluation of iCCS for Different Process Steps iCCS technologies encompass many different technological concepts and potential
target applications. The results presented below are intended to illustrate the acceptance of
iCCS along the stages of different value chains and the underlying factors. It should be
mentioned at the outset that the studies analyzed did not examine in detail the possible
effect of the technical feasibility of different iCCS technologies on iCCS acceptance. y
g
p
The following findings are available on the CO2 source and the capture process step The following findings are available on the CO2 source and the capture process ste •
BECCS: as briefly indicated before, BECCS is preferred to fossil-based CCS. According
to [76], the technological approach has reached a stage of normalization in the debate,
at least in the scientific discourse, after several years of intense criticism, and has
become a self-evident aspect of climate change discourse. Especially for countries with
a strongly biomass-based economy, such as Finland, BECCS seems to generate bene-
fits [75]. With reference to [71], CCS was seen as a more intuitive and natural process
when linked to managed forestry and the carbon cycle. Similarly, ref. [41] presents
the use of biogas plants as a source of CO2 as a promising option for industry and
policy makers to achieve a socially acceptable form of carbon capture. Environmental Sustainability 2021, 13, 12278 17 of 29 17 of 29 organizations such as Greenpeace and Biofuelwatch disagree here, according to [76],
emphasizing problems with agricultural production and water scarcity in the context
of BECCS. This aspect is also critically addressed in the Convention on Biological
Diversity from 2019 [82]. This is because significant negative impacts on biodiversity
and food security are expected as a result of the extensive land use changes caused by
the consistent use of bioenergy, including BECCS. It remains to be seen what effect
this position can have in terms of shaping public opinion. However, ref. [13] assume
that BECCS is more supported than shale gas, underground coal gasification, and the
application of CCS in heavy industry. pp
y
y
Post-combustion capture: while the process can be retrofitted into existing energy
infrastructure, it does not promise economic feasibility due to low efficiency and
increases the need for fossil fuels, thus having a comparatively high environmental
impact. For these reasons, the process is generally not considered beneficial from
the perspective of interviewed stakeholders [69]. 3.2.10. Evaluation of iCCS for Different Process Steps The following findings are available on the acceptance of CO2 use: The following findings are available on the acceptance of CO2 use: •
Methanol production: according to [30], the most preferred way to use CO2 is
methanol production, while the CCS-EOR process chain is perceived as one of the
worst alternatives, second only to CCS without the link to the beneficial use of CO2. y
•
Chemical looping and CO2 removal from calcination processes: these have shown
potential according to [69] in the study area of Finland, especially in small CCU ap-
plications and in some cases also in CHP production. Opportunities to recycle the
captured carbon could help solve the economic feasibility problem due to lower trans-
portation and storage costs and potential revenue from recycling. Whether optimizing
economic feasibility may also have an effect on public perception is not addressed. Sustainability 2021, 13, 12278 18 of 29 •
CO2-based fuel production: ref. [41] make clear that the public is less interested in the
process step of CO2-based fuel production and efficiency improvements in chemical
production, but rather in the processes of CO2 capture and transport. p
p
p
p
•
H2/CCS value chain: ref. [14] represent that the H2 part of this joint value chain is
more socially accepted than the CCS part. Nevertheless, the type of H2 (green, blue,
conventional) is also estimated to be relevant for acceptance. They also hypothesize
that only established larger industries can address these infrastructure issues, but that
the trust on the ground, where the (re)construction of the infrastructure takes place, is
more likely to be given to local stakeholders. The following findings are available on the acceptability of CO2 storage in conjunction
with iCCS: •
Onshore storage: ref. [16] suggest avoiding the NIMBY (not in my backyard) effect in
field trials of CO2 storage using BECCS as the CO2 source. It is likely that the source
of the CO2 is critical to the acceptance of the storage site. •
Offshore storage: Haug’s results show that the possibility of the offshore storage of
CO2 could be a clear advantage for the Nordic regions for the establishment of an
iCCS economy [64]. As an example, the municipality of Porsgrunn in Norway, whose
positive attitude towards existing and potential iCCS activities may result from the
option of offshore storage, should be mentioned once again. 3.2.10. Evaluation of iCCS for Different Process Steps The Sleipner project in
the North Sea was also realized without much public controversy, and ref. [64] suggest
that this could also be a result of the offshore location. In sum, the off-shore option
could be a great advantage for the Nordic region, but it is important to note that it
must also gain the consent of the stakeholders in the use of the sea and that there is no
guarantee of acceptance if these stakeholders are neglected [64]. Geological and infrastructural prerequisites: Countries with an interest in establishing
an iCCS economy should carefully examine their geological prerequisites. According
to [75], CO2 storage is an open question in Finland, as the country lacks potential
geological formations for it, which also underscores the importance and cost of CO2
transport [75]. Russia, on the other hand, has extensive area and therefore allows CO2
storage at a considerable distance from industrial centers and residential areas, which
could potentially weaken stakeholder opposition to the projects [70]. Another option,
he said, is to look at reusing existing infrastructure for CO2 storage, as proposed in
the Acorn project. Significant cost savings can be achieved through this approach,
and this also represents a societal approach to enable broader CCS deployment [78]. For example, existing CO2 transport and storage infrastructure could be shared by
multiple capture projects to maximize value, simplify investment decisions, share
operating costs, and thus reduce development costs. Finally, it should be summed up here that several studies consider the acceptance
of iCCS along the different process steps and value creation stages to be possible. An
important approach to developing iCCS acceptance, initially primarily from an economic
perspective, is the pursuit of a cluster and network approach [14,41,62,64,67,78], which is
already emerging as a trend in practice (see Section 3.2.1 for a more detailed discussion). 3.2.11. Regulatory/Political Aspects This literature review also noted circumstantial evidence suggesting that a lack of
regulatory frameworks, political support, and missing or complex approval processes may
influence iCCS adoption. The findings highlight a fundamental need for strong regulation and policy on iCCS,
both to leverage the skills and experience of the private sector and to maintain the common
good and public interest [65]. For example, a UK opinion poll cited by [62] found that a
majority (74%) of adults support policies to regulate heavy industry to ensure emissions
reductions in the sector. Focus group participants from a region of Scotland that has
historically been closely associated with energy-intensive industry (Port Talbot steelworks)
assume that there will be stricter emissions legislation for these industries in the long Sustainability 2021, 13, 12278 19 of 29 19 of 29 term, and therefore refer to iCCS as an “inevitable” option [62]. This would imply that
expectations of stricter emissions legislation in the future from national and EU levels
alone can convince people that iCCS is inevitable in the future. On the other hand, the
participants of this study also valued the European Union as an important partner for the
implementation of iCCS technologies [60], especially by providing the necessary funding. In this context, ref. [69] also mention the funding for the development of the necessary CO2
transport infrastructure. p
Ref. [30] go one step further and assume that an important factor for further iCCS
development is international cooperation. On the one hand, so that individual countries
can embed and position their iCCS policies internationally [14], and on the other hand,
international cooperation would make it possible to combine national efforts, create favor-
able conditions for project proposals and adopt successful experiences of other countries. Thus, it would be necessary to create a political context that can strengthen public trust due
to the importance of collaborative decision-making [30]. Local and regional networks alone
would be insufficient to influence national policy [14,63]. In addition, ref. [65] describe
that there would be limited public communication of an iCCS project proposal if political
uncertainties prevail. For this, it is also important to have political long-term strategies
that create reliability, for example, regarding BECCS technology and its integration into
the European Union Emissions Trading Scheme (ETS-EU) [77]. This integration would
be important for Finland, for example. 3.2.11. Regulatory/Political Aspects Without BECCS, it would be challenging to meet
emissions targets, but with BECCS, Finland could gain benefits by saving and trading
emissions allowances [75]. The need for ETS-EU was frequently mentioned in the analyzed
studies, but mostly by industrial actors and other experts [69,75,77]. 4. Discussion range of technological options and the resulting societal implications, this task also appears
to be non-trivial. The discussion of objectives 3 (factors influencing iCCS) and 4 (differences of CCS and
iCCS) of this content analysis are now discussed in conjunction. More specifically, acceptance at the regional level, for example, appears to depend even
more significantly on the perceived societal benefits that people associate with iCCS. The
potential to maintain and increase local employment through the use of iCCS applications
was frequently mentioned [13,64,66,71]. This represents a difference from the debate in
perceptions of the societal benefits of CCS. In sum, it appears as if the population expects
the safeguarding or even increasing of economic performance in their local environment
with the use of iCCS. Previous research findings illustrate that societal benefits have
either the same or slightly higher explanatory power for CCS acceptance than societal
risks [31,35,47,83] (see Table 1). Whether this is also valid for the acceptance of iCCS
remains to be investigated. g
What is clear is that both factors will also be very significant in the context of iCCS. Subjectively perceived risk associated with CO2 storage has been a crucial factor in explain-
ing local and regional resistance in the context of CCS technologies [11,16,44]. It is different
from factual risk in this regard as [53] illustrated with their approach to misconceptions. The fact is that CO2 pipelines are state of the art and have been operating in the United
States for example since the 1970s. Additionally, no significant research and development
budgets are being spent on CO2 transport and the associated potential risks worldwide. In
contrast, geological storage of CO2 has been the subject of intensive research and devel-
opment work internationally for many years, even though CO2 storage is already being
successfully operated in many countries [84]. Here, the exploration methods for CO2 stor-
age, the procedures for storage monitoring, the competition with other storage utilization
options, the impact on geothermal energy utilization, and the theoretically possible effects
on drinking water supplies are often the subject of interest [85]. In sum, the question is not
so much whether CO2 storage is fundamentally possible, but under what conditions it is as
safe as possible. 4. Discussion The present study is the first literature review to address the acceptance of iCCS. The
objective of this study was fourfold. Firstly, it is examined to what extent the acceptance
of iCCS is already being empirically investigated. Secondly, an analytical framework is
proposed in order to systematically review the existing literature. Thirdly, based on the
review, factors influencing the acceptance of iCCS are identified and discussed. Fourthly,
results for the acceptance of iCCS are compared to CCS, highlighting some important
differences between the two areas of application. pp
First, the results show that there is still only limited research on the acceptance of
iCCS. Between 2012 and 2020, 25 scientific articles were published on the subject, with very
different and incomparable methodological tools and research questions. Secondly, during the evaluation process, it became apparent that the analytical frame-
work transferred from CCS acceptance research, with its well-established dimensions (cf. Table 1), was sufficient to systematically gather the results from the articles. The research
findings of the analyzed articles could be assigned to one or more dimensions, such as
findings on local aspects (as suggested by Table A1 in the Appendix A, see column “Im-
portant statement related to iCCS”). Influencing variables that emerged in the analyzed
articles and initially deviated from the established factors for CCS acceptance research
(for example, the employment factor) could be assigned to the existing dimensions by the
author during the evaluation. Accordingly, no further factors were inductively added to
the analytical framework established in Section 2. As a result, many factors explaining
the acceptance of CCS seem to be decisive for the acceptance of iCCS as well. However,
it became apparent that the weighting and the expressions of acceptance factors to iCCS
appears to vary compared to CCS, as shown in the following. Moreover, only tentative
trends for the acceptance of iCCS can be derived from the studies analyzed. It remains
unclear whether iCCS applications are more likely to be accepted or rejected by society
in the future. Moreover, from a scientific point of view, a methodological concept for
analyzing iCCS acceptance is still lacking, even though the factors considered here already
provide a good starting point for operationalizing the research subject. Given the wide Sustainability 2021, 13, 12278 20 of 29 20 of 29 range of technological options and the resulting societal implications, this task also appears
to be non-trivial. 4. Discussion Another
research question could be whether the CO2 source has an influence on the acceptance Sustainability 2021, 13, 12278 21 of 29 21 of 29 of CO2 transport, for example if the source is associated with an industry that is deeply
rooted in the local society and contributes to its identity. of CO2 transport, for example if the source is associated with an industry that is deeply
rooted in the local society and contributes to its identity. In this context, the role of framing or a possible narrative for iCCS (and also the
greenhouse gas CO2) implementation should also be further explored. The studies have
illustrated that framing iCCS as a climate change mitigation technology can lead to both
positive and negative acceptance tendencies [13,16,53,63–65,71]. There does not seem to
be a determination yet as to whether or not iCCS technologies are perceived by society as
a climate change technology. This framing was hardly conceivable in the context of the
CCS debate since there were sufficient technological alternatives for sustainable generation
of electricity through the use of renewable energy technologies. Anyway, it is clear that
iCCS operators would benefit from such “green” framing of iCCS applications, especially
in marketing potential products along the value chain. This framing approach, based on
a rather economically oriented marketing strategy, would certainly fall short. Ultimately,
there is an obvious need for a more overarching narrative that takes into account both
the aspect of sustainability and the reduction of CO2, as well as economic issues that not
only affect individual technology paths, but in sum relate to the economic viability of an
entire region. As a consequence, this would mean embedding iCCS in a discourse around
sustainable structural change. After all, regions with energy-intensive economic sectors are
particularly affected by the challenge of structural change. The articles analyzed have also made it clear that the factors of social “values and
attitudes” can be significant for the acceptance of iCCS [13,14,30,62,64,65,71,74,76]. In
this context, further research is particularly needed on the question of whether a certain
environmental awareness has a positive or negative influence on the perception of iCCS. Compared to the CCS context, the clarification of this research question seems to be much
more complex due to the many different possible applications of iCCS. 4. Discussion In the context of CCS
acceptance, existing studies indicate that people with high environmental awareness tend
to evaluate the technology negatively [49,86]. Some authors mentioned that, triggered by
the Paris Agreement, the absolute urgency of the transformation to a sustainable economy
and way of life has now arrived in the perception of society. In light of this urgency, the
evaluation of iCCS could also be developed in a more positive direction [63,65]. Again,
there are only assumptions and no evidence-based findings yet. Interestingly, in one study,
this urgency emerged as a driver of iCCS acceptance. This happens when this urgency is
interpreted by society as a threat to their current lifestyles and cherished habits for everyday
life, and iCCS is perceived as an option to hold on to these habits without regret [71]. This
approach could also be a starting point for new research questions on the acceptance of
iCCS. In addition to this urgency, another aspect could influence the perception of iCCS
in the future. For example, the Global Assessment Report on Biodiversity and Ecosystem
Services (IPBES) [87] does not exclude CCS (and thus iCCS) as a measure to mitigate
negative impacts on biodiversity (see Glossary). Consequently, iCCS could be considered
not only an option to reduce global CO2 emissions, but also a generally accepted measure to
avoid or limit potential negative impacts on biodiversity. If such a perception is perpetuated
among individuals with a high level of environmental awareness, this aspect could be
interpreted as an advantage for the use of iCCS and possibly have a positive impact on
social acceptance. Whether this assumption is well-founded needs to be explored in future
studies on the acceptance of iCCS. 4. Discussion Besides these science-based facts of technical and environmental aspects,
the subjectively perceived risk factor will be important in the context of iCCS acceptance, as
many of the studies analyzed have made clear [13–15,30,62,65,68,71,73–77]. It seems that in
this context the aspect of fair distribution of risks and benefits has to be more in focus than
in the context of the CCS debate. If, in the future, the benefits associated with the use of
iCCS are perceived by the population primarily at the global level in the context of climate
protection and the local population gains the impression that, in contrast, they are more
likely to be confronted with the disadvantages of iCCS applications, this would probably
be a barrier to the development of acceptance. In relation to the perception of an equitable
distribution of risks and benefits, the explicit understanding of the benefits associated with
iCCS for a region therefore seems to be of importance. This starting point of an unequal
distribution of risks and benefits in the context of the future deployment of iCCS offers
a possible field of action, both for research and for the implementation of practical iCCS
projects. The previous research approaches of possible compensation benefits in the context
of CCS will be examined here for their transferability and applicability. Furthermore, the factor trust, which was evaluated in most studies as an important
tipping point for or against the acceptance of iCCS (see [13–15,30,62,64,65,74]), should
be further investigated. It became clear that in the development of local iCCS projects,
trust in the stakeholders involved becomes especially important when it comes to large
infrastructure measures related to CO2 transport [13,16,41,62]. It seems that the process
step of transport has become critical to the CCS debate, even though the negative sign in
the assessment of CO2 pipelines does not seem to have changed. With respect to transport
infrastructure, more knowledge is still needed on the acceptance of iCCS. It is unclear
whether, for example, the “joint” use of infrastructure or the use of existing infrastructure
by industry clusters or hubs leads to an improvement in the acceptance of iCCS. 5. Conclusions The IEA [88] estimates that iCCS in the cement, iron and steel, and chemicals sectors
will need to deliver around 28GtCO2 of emission reductions between now and 2060 to
meet the climate target of the Paris Agreement. To achieve these reduction goals globally,
strategies for robust and timely market introduction of iCCS technologies need to be
developed. For such a market introduction of iCCS, social acceptance is of particular
importance in addition to technical-economic and environmental indicators, as the example
of CCS has illustrated. Sustainability 2021, 13, 12278 22 of 29 22 of 29 In the studies analyzed, a large number of indications for the design of a communi-
cation strategy were derived, largely on the basis of the findings from CCS acceptance
research as well as on the basis of all the research on energy transformation (see Table 3). In
view of the abovementioned abundance of requirements for such an iCCS communication,
the question arises as to which institution is capable of organizing such a permanent and
trust-based process and in which larger thematic context this communication can be embed-
ded? This appears to be a difficult question to answer, especially against the background of
often missing political strategies and the related regulatory frameworks on the national
level. The present literature analysis shows on the one hand which starting points for
the market introduction of iCCS exist so far from social science research for political and
economic actors and on the other hand which research efforts are still required. Funding: This research received no external funding. Funding: This research received no external funding. Data Availability Statement: The articles used in the literature analysis can be accessed via the
respective publishers (for more details, see the bibliography). Data Availability Statement: The articles used in the literature analysis can be accessed via the
respective publishers (for more details, see the bibliography). Appendix A Table A1. Overview of the analyzed articles. First Author (Year
of Publication)
[Reference]
Method
Country
iCCS-Related
Technology
Important Statement in Relation to
iCCS
Alcalde et al. (2019)
[78]
Evaluation of ACT
Acorn findings
and review
of schol-
arly/industrial
literature
UK
Complete iCCS value
chain (Acorn Project)
Seven key elements for iCCS projects:
Infrastructure reuse, storage
development plan, low-carbon
build-out options, full-chain
development plan, policy support,
just transition, public engagement,
and knowledge exchange. Aursland et al. 5. Conclusions (2019) [66]
Case study with
local residents and
Norcem employees
(n = 15, face-to-face)
NO
CO2 capture from the
cement industry
Positive image of cement company
conducive to acceptance, effects on
local employment and environment
perceived as benefits. However, also
concern whether project affects local
living conditions. Boomsma et al. (2020) [74]
Literature review
from academic
literature
(non-systematic,
n = N/A) and
publicly available
documents (n = 25)
Academic
literature:
international;
public documents
(DE = 7, NL = 4,
RO = 5, UK = 9)
No specific iCCS
technique defined
(focus on community
compensation)
When implementing iCCS projects, it
is important to understand local social
conditions and examine what impact
they have. Sites where the local public
feels connected to the industry may be
more positive about iCCS
development. Compensation for
communities needs to be integrated
into broader public
involvement strategies. Broecks et al. (2016) [63]
Quantitative online
survey
representative for
NL (n = 920) and
discrete choice
experiment
NL
No specific iCCS
technique defined
(=industrial
applications)
“Industrial applications” is the most
convincing pro-argument for CCS,
followed by “dispose of CO2
garbage”, “safety of natural gas
fields”. Arguments on climate change
are less convincing. Table A1. Overview of the analyzed articles. “Industrial applications” is the most
convincing pro-argument for CCS,
followed by “dispose of CO2
garbage”, “safety of natural gas
fields”. Arguments on climate change
are less convincing. No specific iCCS
technique defined
(=industrial
applications) 23 of 29 Sustainability 2021, 13, 12278 Table A1. Cont. First Author (Year
of Publication)
[Reference]
Method
Country
iCCS-Related
Technology
Important Statement in Relation to
iCCS
de Best-
Waldhober et al. (2012) [17]
Quantitative study
(ICQ 1)
representative for
NL (n = 971)
NL
Large plants where
gas is converted into
hydrogen with CCS
iCCS option rated lower compared to
other energy production/mitigation
options (except nuclear). Dütschke et al. (2015) [61]
Quantitative online
experimental
survey design
representative for
DE (n = 1.672),
assessment of
18 scenarios
DE
Industry and biomass
power plant as
CO2 source
CCS scenarios that include either an
energy-intensive industry or a
biomass power plant as a source of
CO2 are perceived more positively
than scenarios in which the CO2 is
captured from a coal-fired power
plant. Rating of the respective CO2
source as the strongest predictor. Glanz et al. 5. Conclusions (2021) [15]
Qualitative
explorative
stakeholder
interviews (n = 10)
DE
Hydrogen and carbon
capture and storage
infrastructure/ chain
Restricting the use of CCS for certain
applications (industry, bioenergy)
represent trade-offs that are supported
by various stakeholder groups and
offer a balance of environmental and
economic arguments. Assumption:
only large industries can address
iCCS/H2 and its infrastructure
challenges, but local trust is given to
other stakeholders. Gough et al. (2018) [14]
Mixed-methods
approach:
stakeholder
interviews (n = 12)
and two focus groups
(n = 8 each group)
with lay public
UK
iCCS with focus on
CO2 storage
Success of iCCS activities in a
community dependent on social
context, trust in key actors, track
record of previous industrial
processes. Hurdles related to
procedural justice. Haikola (2019) [76]
Qualitative analysis
of (popular) science
and news media
from 2008—2018
(n= ca. 800)
International
BECCS
Scientific discussion about BECCS is
becoming more neutral due to the
time pressure to take action on climate
protection. Debate moves away from
the question of moral hazard and
focuses instead on the need to act. Haug et al. (2016)
[64]
Interviews with
municipalities
(n = N/A 2) and
literature review
DK, NO, SE
No specific iCCS
technique defined
Communities can consider iCCS as an
advantage for regional value creation. Positive evaluation if local population
is used to industrial activities and has
concrete iCCS experience. Potential
for offshore storage in a region is
evaluated as an advantage. Ilinova et al. (2018) [70]
Case studies
(n = N/A),
stakeholder
management tools,
and a checklist
method
International
No specific iCCS
technique defined
Most attention in CCS project
planning/implementation should be
focused on industrial
companies/investors, government and
society. CCS projects are mostly local
projects; however, they are implemented
in the context of national and even
international interests. Therefore, the
circle of stakeholders is large and
establishing a constructive dialogue
with all proves to be a difficult task. Table A1. Cont. Restricting the use of CCS for certain
applications (industry, bioenergy)
represent trade-offs that are supported
by various stakeholder groups and
offer a balance of environmental and
economic arguments. Assumption:
only large industries can address
iCCS/H2 and its infrastructure
challenges, but local trust is given to
other stakeholders. 24 of 29 Sustainability 2021, 13, 12278 Table A1. Cont. First Author (Year
of Publication)
[Reference]
Method
Country
iCCS-Related
Technology
Important Statement in Relation to
iCCS
Kashintseva et al. 5. Conclusions (2018) [65]
Empirical model
based on
representative
online survey
(n = 564)
CZ, DE, IT, NL,
PL, SK, UK
No specific iCCS
technique defined
(iCCS products and
technologies)
Increase of iCCS sites, including those
in the neighboring regions and
countries, leads to the increase of
negative consumer attitudes to iCCS
and renewable energy policies. NIMBY effect is considered relevant. Kojo et al. (2017) [75]
Quantitative
longitudinal
analysis of
newspaper articles
from 1996–2015
(n = 282)
FI
No specific iCCS
technique defined
(pertains to BECCS)
Agenda setting of the media regarding
CCS is strongly dependent on real
plant projects and communication
measures of industrial actors. iCCS
actors are not yet involved in
communication in Finland. Business
models are missing, costs are
overestimated, a debate specifically
about possible international
developments is missing. Offermann-van
Heek et al. (2020) [41]
Quantitative online
survey
representative for
DE (n = 300) and
best-/worst-case
scenarios
DE
DAC, biogas and
chemical plant
Capture and transport process step
more relevant to public than further
use of CO2, use of existing
infrastructure conducive to
acceptance, CO2 use from BECCS and
chemical plants viewed positively,
DAC not an accepted option. Pihkola et al. (2017) [69]
PESTEL 3
framework
(analysis macro-
environment of
industries),
stakeholder
interviews (n = 12)
from 2011–2012,
media analyses
(n = N/A),
literature reviews
FI
No specific iCCS
technique defined
(pertains to BECCS)
iCCS needs a regulatory framework
and political support, especially for
the development of infrastructure. More systematic and differentiated
consideration of iCCS applications is
required for Finland. BECCS/CCU is
seen as an opportunity for iCCS due
to the central role of the Finnish
energy-intensive industry. Rodriguez et al. (2020) [77]
Qualitative
inductive
interviews with
company
representatives
(n = 20)
FI, SE
BECCS
BECCS is technically feasible; what
remains unclear is who will create a
financially viable business case and
establish supporting policies, as well
as who will build the necessary
transportation and storage
infrastructure. In addition, customer
requirements for negative emissions
are still lacking. Serdoner (2019) [73]
Qualitative
interviews (n = 3)
with representatives
of EU
environmental
organizations,
analysis of their
public relations
activities and
literature review
EU
No specific iCCS
technique defined
Positions of ENGOs operating in
Europe on iCCS are closely related to
previous debates on the application of
the same technology in the power
sector. Previous experience has led
ENGO to approach the technology
with skepticism and caution. 5. Conclusions They are
either neutral toward iCCS or
opposed to it. Table A1. Cont. iCCS needs a regulatory framework
and political support, especially for
the development of infrastructure. More systematic and differentiated
consideration of iCCS applications is
required for Finland. BECCS/CCU is
seen as an opportunity for iCCS due
to the central role of the Finnish
energy-intensive industry. 25 of 29 Sustainability 2021, 13, 12278 Table A1. Cont. First Author (Year
of Publication)
[Reference]
Method
Country
iCCS-Related
Technology
Important Statement in Relation to
iCCS
Swennenhuis et al. (2020) [65]
In-depth
semi-structured
interviews (n = 25)
with regional
stakeholders and
workshops (UK)
NO, NL, UK
No specific iCCS
technique defined
Narrative that iCCS is deployed for
benefit of
citizens/communities/workers and
not in support of private sector, policy
that leverages private sector
capabilities without setting aside the
public interest, need for deeper
engagement with local governments
that act as facilitators for
iCCS deployment. Tcvetkov et al. (2019) [30]
Literature review
from 2002–2018
(n = 135)
international
No specific iCCS
technique defined
Development of a regulatory
framework to control the industry,
important for public trust.Public
preferences regarding capture plants
are explained by problems with
existing energy infrastructure. Public
trust in environmental arguments of
industry lower compared to NGOs,
arguments of industry about economic
aspects of project implementation are
better perceived than by NGOs. Thomas et al. (2018) [71]
Two qualitative
deliberative
workshops with
local population
(n= 12 each)
UK
Industrial CCS and
BECCS
Depending on the context, iCCS may
be perceived as a threat or a support
to local social and economic
interdependence. As a threat, for
example, through costs that could
harm employment in local industries,
as a benefit through protecting and at
the same time rejuvenating historical
employment patterns through iCCS. van Os (2018) [72]
Interview with
Peter van Os
NL
Complete iCCS value
chain (ALIGN CCUS
Project)
Assumption that there will be a more
positive perception of CCUS as the
public becomes more aware of their
individual impacts on climate. Uncertainties related to the cost of
implementing CCUS, costs will
decrease as implementation of CCUS
technology progresses. Wallquist et al. (2012) [16]
Online Experiment
(n = 139)
CH
BECCS
CO2 source decisive for acceptance of
storage site, avoidance of CO2 pipeline
transport in densely populated areas,
avoidance of the NIMBY effect through
the use of BECCS. Whitmarsh et al. References 1. IPCC. Fifth Assessment: Report of the Intergovernmental Panel on Climate Change. In Contribution of Working Group III;
Cambridge University Press: Cambridge, UK, 2014. 1. IPCC. Fifth Assessment: Report of the Intergovernmental Panel on Climate Change. In Contribution of Working Group III;
Cambridge University Press: Cambridge, UK, 2014. 2. UNFCCC. Addendum Contents Part two: Action taken by the Conference of the Parties at its twenty-first session. In Proceed-
ings of the Conference of the Parties on Its Twenty-First Session; Paris, France, 30 November–13 December 2015, UNFCC: Bonn,
Germany, 2015. y
3. IEA. 20 Years of Carbon Capture and Storage. Accelerating Future Deployment; International Energy Agency: Paris, France, 2016. 4
IEA W
ld E
O tl
k 2018 I t
ti
l E
A
P
i
F
2018 ISBN 978 92 64 30677 6 y
3. IEA. 20 Years of Carbon Capture and Storage. Accelerating Future Deployment; International Energy Agency: Paris, France, 2016. 4
IEA W
ld E
O tl
k 2018 I t
ti
l E
A
P
i
F
2018 ISBN 978 92 64 30677 6 y
A. 20 Years of Carbon Capture and Storage. Accelerating Future Deployment; International Energy Agency: Paris 5. IPCC. Global Warming of 1.5 ◦C. An IPCC Special Report on the Impacts of Global Warming of 1.5 ◦C above Pre-Industrial Levels and
Related Global Greenhouse Gas Emission Pathways, in the Context of Strengthening the Global Response to the Threat of Climate Change,
Sustainable Development, and Efforts to Eradicate Poverty; Intergovernmental Panel on Climate Change: Geneva, Switzerland, 2018;
Available online: https://www.ipcc.ch/site/assets/uploads/sites/2/2019/06/SR15_Full_Report_High_Res.pdf (accessed on 19
December 2020). )
6. Bui, M.; Adjiman, C.S.; Bardow, A.; Anthony, E.J.; Boston, A.; Brown, S.; Fennell, P.S.; Fuss, S.; Galindo, A.; Hackett, L.A. Carbon
capture and storage (CCS): The way forward. Energy Environ. Sci. 2018, 11, 1062–1176. [CrossRef] 7. IEA—International Energy Agency. World Energy Outlook 2015; International Energy Agency: Paris, France, 2015; Available
online: https://www.globalccsinstitute.com/wp-content/uploads/2019/08/Introduction-to-Industrial-CCS.pdf (accessed on 19
December 2020). 8. Global CCS Institute. The Global Status of CCS. Special Report: Introduction Industrial Carbon Capture and Storage; Global CCS
Institute: Melbourne, Australia, 2016. 9. Dütschke, E.; Schumann, D.; Pietzner, K. Chances for and Limitations of Acceptance for CCS in Germany. In Geological Storage of
CO2—Long Term Security Aspects, Advanced Technologies in Earth Sciences; Springer: Cham, Switzerland, 2015; pp. 229–245. 10. Terwel, B.W. 5. Conclusions (2019) [13]
International
experimental online
study (n = 5.406),
national and
local samples
CA, NL, NO,
UK, US
No specific iCCS
technique defined
Bioenergy with CCS is more
supported, while shale gas,
underground coal gasification, and
heavy industry with CCS are less
supported. Areas where CCS facilities
are likely to be built are typically
locations where (analogous) industry
already exists. Subjective familiarity
with this industry could serve to
reduce perceived risks associated with
new infrastructure. Table A1. Cont. iCCS-Related
Technology
Important Statement in Relation to
iCCS Bioenergy with CCS is more
supported, while shale gas,
underground coal gasification, and
heavy industry with CCS are less
supported. Areas where CCS facilities
are likely to be built are typically
locations where (analogous) industry
already exists. Subjective familiarity
with this industry could serve to
reduce perceived risks associated with
new infrastructure. 26 of 29 Sustainability 2021, 13, 12278 Table A1. Cont. First Author (Year
of Publication)
[Reference]
Method
Country
iCCS-Related
Technology
Important Statement in Relation to
iCCS
Williams et al. (2021) [62]
Two qualitatively
designed focus
groups with
citizens (n = 11 and
n = 10)
UK
iCCS in the steel
industry
Community could endorse use of
iCCS if developer/government
collaborate from local to national level,
provide transparent dialogue process
that supports community trust in
intent, integrity, and competence of
implementing organizations. Xenias et al. (2018)
[68]
Mixed-methods
approach:
interviews (n = 13)
and online survey
(n = 99)
with experts
Interviews: NO,
NL, UK; Online
survey: DE, NL,
NO, UK, others
No specific iCCS
technique defined
Need to expand CCS discussion to
heavy industry, iCCS benefits at global
level and greater risks at local level,
learning from public engagement
research literature
1 ICQ = Information-Choice Questionnaire; 2 N/A = not available; 3 PESTEL = Political, economic, social, technological, environmental, legal. Table A1. Cont. References Transit. 2020, 35, 292–308. [CrossRef] 21. Arning, K.; Zaunbrecher, B.S.; Sternberg, A.; Bardow, A.; Ziefle, M. Blending Acceptance as Additional Evaluation Parameter into
Carbon Capture and Utilization Life-Cycle Analyses. In SMARTGREENS—7th International Conference on Smart Cities and Green
ICT Systems; Science and Technology Publications SciTePress: Setubal, Portugal, 2018; pp. 34–43. y
gy
g
pp
22. Heek, J.O.-V.; Arning, K.; Linzenich, A.; Ziefle, M. Trust and distrust in Carbon Capture and Utilization industry as relevant
factors for the acceptance of carbon-based products. Front. Energy Res. 2018, 6, 73. [CrossRef] p
p
gy
23. Jones, C.R.; Olfe-Kräutlein, B.; Kaklamanou, D. Lay perceptions of Carbon Dioxide Utilisation technologies in the United
Kingdom and Germany: An exploratory qualitative interview study. Energy Res. Soc. Sci. 2017, 34, 283–293. [CrossRef]
24
Available online: https://www elsevier com/solutions/sciencedirect (accessed on 2 December 2020) 25. Ware, M.; Mabe, M. The STM Report: An Overview of Scientific and Scholarly Journal Publishing; International Association of Scientific,
Technical and Medical Publishers: The Hague, The Netherlands, 2015. 27. Liberati, A.; Altman, D.G.; Tetzlaff, J.; Mulrow, C.; Gøtzsche, P.C.; Ioannidis, J.P.A.; Clarke, M.; Devereaux, P.J.; Kleijnen, J.;
Moher, D. The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care
Interventions: Explanation and Elaboration. PLoS Med. 2009, 62, e1–e34. p
28. Gläser, J.; Laudel, G. Experteninterviews Und Qualitative Inhaltsanalyse Als Instrumente Rekonstruierender Untersuchungen, 4th ed.;
Lehrbuch; VS Verlag Für Sozialwissenschaften: Wiesbaden, Germany, 2010; ISBN 978-3-531-17238-5. 29. L’Orange Seigo, S.; Dohle, S.; Siegrist, M. Public perception of carbon capture and storage (CCS): A review. Renew. Sustain. Energy
Rev. 2014, 38, 848–863. [CrossRef] 30. Tcvetkov, P.; Cherepovitsyn, A.; Fedoseev, S. Public perception of carbon capture and storage: A state-of-the-art overview. Heliyon
2019, 5, e02845. [CrossRef] 31. Gough, C.; Taylor, I.; Shackley, S. Burying Carbon under the Sea: An Initial Exploration of Public Opinions. Energy Environ. 2002,
13, 883–900. [CrossRef] 32. Haug, P. Public acceptance: A wake-up call from the people of Europe. In World Nuclear Association Annual Symposium; World
Nuclear Association: London, UK, 2002; pp. 4–6. 33. Huijts, N. Public Perception of Carbon Dioxide Storage. The Role of Trust and Affect in Attitude For
Eindhoven University of Technology, Eindhoven, The Netherlands, 2003. 34. Huijts, N.M.A.; Molin, E.J.E.; Steg, L. Psychological factors influencing sustainable energy technology acceptance: A review-based
comprehensive framework. Renew. Sustain. Energy Rev. 2012, 16, 525–531. [CrossRef] p
gy
35. Kraeusel, J.; Möst, D. References Public participation under conditions of distrust: Invited commentary on ‘Effective risk communication and CCS:
The road to success in Europe’. J. Risk Res. 2015, 18, 692–694. [CrossRef] 11. Schumann, D.; Duetschke, E.; Pietzner, K. Public perception of CO2 offshore storage in Germany: Regional differences and
determinants. Energy Procedia 2014, 63, 7096–7112. [CrossRef] y
rs, E.; Daamen, D.D.L. It’s not only about safety: Beliefs and attitudes of 811 local residents regarding a CCS
ht. Int. J. Greenh. Gas Control 2012, 9, 41–51. [CrossRef] 12. Terwel, B.W.; ter Mors, E.; Daamen, D.D.L. It’s not only about safety: Beliefs and attitudes of 811 local r
project in Barendrecht. Int. J. Greenh. Gas Control 2012, 9, 41–51. [CrossRef] project in Barendrecht. Int. J. Greenh. Gas Control 2012, 9, 41 51. [CrossRef]
13. Whitmarsh, L.; Xenias, D.; Jones, C.R. Framing effects on public support for carbon capture and storage. Palgrave Commun. 2019,
5, 17. [CrossRef] 13. Whitmarsh, L.; Xenias, D.; Jones, C.R. Framing effects on public support for carbon capture and storage
5, 17. [CrossRef] 14. Gough, C.; Cunningham, R.; Mander, S. Understanding key elements in establishing a social license for CCS: An empirical
approach. Int. J. Greenh. Gas Control 2018, 68, 16–25. [CrossRef] pp
J
15. Glanz, S.; Schönauer, A.-L. Towards a Low-Carbon Society via Hydrogen and Carbon Capture and Storage: Social Acceptance
from a Stakeholder Perspective. J. Sustain. Dev. Energy Water Environ. Syst. 2021, 9, 9. [CrossRef] 16. Wallquist, L.; Seigo, S.L.; Visschers, V.H.M.; Siegrist, M. Public acceptance of CCS system elements: A conjoint measurement. Int. J. Greenh. Gas Control 2012, 6, 77–83. [CrossRef] Sustainability 2021, 13, 12278 27 of 29 27 of 29 17. De Best-Waldhober, M.; Daamen, D.; Ramirez, A.R.; Faaij, A.; Hendriks, C.; de Visser, E. Informed public opinion in the
Netherlands: Evaluation of CO2 capture and storage technologies in comparison with other CO2 mitigation options. Int. J. Greenh. Gas Control 2012, 10, 169–180. [CrossRef] ,
,
[
]
18. 2000. Available online: https://CO2re.co/FacilityData (accessed on 20 December 2020). p //
/
y
(
)
19. Renn, O. Technikakzeptanz: Lehren und Rückschlüsse der Akzeptanzforschung für die Bewältigung des technischen Wandels. Tech. Theor. Prax. 2005, 14, 29–38. [CrossRef] 19. Renn, O. Technikakzeptanz: Lehren und Rückschlüsse der Akzeptanzforschung für die Bewältigu
Tech. Theor. Prax. 2005, 14, 29–38. [CrossRef] 20. Arning, K.; Heek, J.O.-V.; Sternberg, A.; Bardow, A.; Ziefle, M. Risk-benefit perceptions and public acceptance of Carbon Capture
and Utilization. Environ. Innov. Soc. References [CrossRef] 28 of 29 Sustainability 2021, 13, 12278 28 of 29 46. Zhang, L.; Wang, J.; You, J. Consumer environmental awareness and channel coordination with two substitutable products. Eur. J. Oper. Res. 2015, 241, 63–73. [CrossRef] p
47. Krause, R.M.; Carley, S.; Warren, D.C.; Rupp, J.A.; Graham, D. “Not in (or under) my backyard”: Geographic proximity and
public acceptance of carbon capture and storage facilities. Risk Anal. 2014, 34, 529–540. [CrossRef] p
p
p
g
48. Ter Mors, E.; Terwel, B.W.; Zaal, M.P. Can monetary compensation ease the siting of CCS projects? Energy Procedia 2014, 63,
7113–7115. [CrossRef] 49. Yang, L.; Zhang, X.; McAlinden, K.J. The effect of trust on people’s acceptance of CCS (carbon capture and storage) technologies:
Evidence from a survey in the People’s Republic of China. Energy 2016, 96, 69–79. [CrossRef] 50. Lock, S.J.; Smallman, M.; Lee, M.; Rydin, Y. “Nuclear energy sounded wonderful 40 years ago”: UK citizen views on CCS. Energy
Policy 2014, 66, 428–435. [CrossRef] jts, N.M.A. The Role of Trust in the Affective Evaluation of Novel Risks: The Case of CO2 Storage. Risk Anal
CrossRef] 51. Midden, C.J.H.; Huijts, N.M.A. The Role of Trust in the Affective Evaluation of Novel Risks: The Case o
2009, 29, 743–751. [CrossRef] 52. Curry, T.E.; Ansolabehere, S.; Herzog, H. A Survey of Public Attitudes towards Climate Change and Climate Change Mitigation
Technologies in the United States: Analyses of 2006 Results; Massachusetts Institute of Technology: Cambridge, MA, USA, 2007. 53. Wallquist, L.; Visschers, V.H.M.; Siegrist, M. Impact of Knowledge and Misconceptions on Benefit and Risk Perception of CCS. Environ. Sci. Technol. 2010, 44, 6557–6562. [CrossRef] [PubMed] 54. Sacuta, N.; Anderson, K. Creating core CCS messages: Focus Group Testing and Peer Review of Questions and Answers from the
IEAGHG Weyburn-midale CO2 Monitoring and Storage Project. Energy Procedia 2014, 63, 7061–7069. [CrossRef] 55. Ashworth, P.; Wade, S.; Reiner, D.; Liang, X. Developments in public communications on CCS. Int. J. Greenh. Gas Control 2015, 40,
449–458. [CrossRef] 56. Brunsting, S.; Upham, P.; Dütschke, E.; De Best Waldhober, M.; Oltra, C.; Desbarats, J.; Riesch, H.; Reiner, D. Communicating
CCS: Applying communications theory to public perceptions of carbon capture and storage. Int. J. Greenh. Gas Control 2011, 5,
1651–1662. [CrossRef] 57. Daamen, D.D.; Terwel, B.W.; Ter Mors, E.; Reiner, D.M.; Schumann, D.; Anghel, S.; Boulouta, I.; Cismaru, D.M.; Constantin, C.; de
Jager, C.C. References Decarbonising steel production using CO2 Capture and Storage (CCS): Results of
f
di
i
i
W l h t
l
ki
it
I t J G
h G
C
t
l 2021 104 103218 [C
R f] y
p
g
p
p
g
62. Williams, R.; Jack, C.; Gamboa, D.; Shackley, S. Decarbonising steel production using CO2 Capture and Storage (CCS): Results of
focus group discussions in a Welsh steel-making community. Int. J. Greenh. Gas Control 2021, 104, 103218. [CrossRef] 62. Williams, R.; Jack, C.; Gamboa, D.; Shackley, S. Decarbonising steel production using CO2 Capture and Storage (CCS): Results of
focus group discussions in a Welsh steel-making community. Int. J. Greenh. Gas Control 2021, 104, 103218. [CrossRef]
63
B
k
K P
E
d S
Rij
F J V li d
d
B
M H kk
t M P P
i
i
t
d J
y
g
p
g
2
p
g (
)
focus group discussions in a Welsh steel-making community. Int. J. Greenh. Gas Control 2021, 104, 103218. [CrossRef] y
g
p
g
p
g
focus group discussions in a Welsh steel-making community. Int. J. Greenh. Gas Control 2021, 104, 103218. [CrossRef]
63
Broecks K P; van Egmond S ; van Rijnsoever F J ; Verlinde van den Berg M ; Hekkert M P Persuasiveness importance and 63. Broecks, K.P.; van Egmond, S.; van Rijnsoever, F.J.; Verlinde-van den Berg, M.; Hekkert, M.P. Persuas
novelty of arguments about Carbon Capture and Storage. Environ. Sci. Policy 2016, 59, 58–66. [CrossRe g
j
g
ovelty of arguments about Carbon Capture and Storage. Environ. Sci. Policy 2016, 59, 58–66. [CrossRef] y
g
p
g
y
64. Haug, J.K.; Stigson, P. Local acceptance and communication as crucial elements for realizing CCS in the Nordic region. Energy
Procedia 2016, 86, 315–323. [CrossRef] [
]
65. Swennenhuis, F.; Mabon, L.; Flach, T.A.; de Coninck, H. What role for CCS in delivering just transitions? An evaluation in the
North Sea region. Int. J. Greenh. Gas Control 2020, 94, 102903. [CrossRef] g
66. Aursland, K.; Jordal, A.B.K. Case study of communication and social perceptions towards CCS in the cement industry. In
Proceedings of the 14th Greenhouse Gas Control Technologies Conference, Melbourne, Austria, 21–26 October 2018. ursland, K.; Jordal, A.B.K. Case study of communication and social perceptions towards CCS in the cem Proceedings of the 14th Greenhouse Gas Control Technologies Conference, Melbourne, Austria, 21 26 October 2018. 67. References Scrutinizing the impact of CCS communication on opinion quality: Focus group discussions versus Information-Choice
Questionnaires: Results from experimental research in six countries. Energy Procedia 2011, 4, 6182–6187. [CrossRef] 58. Ter Mors, E.; Terwel, B.W.; Daamen, D.D.; Reiner, D.M.; Schumann, D.; Anghel, S.; Boulouta, I.; Cismaru, D.M.; Constantin, C.; de
Jager, C.C. A comparison of techniques used to collect informed public opinions about CCS: Opinion quality after focus group
discussions versus information-choice questionnaires. Int. J. Greenh. Gas Control 2013, 18, 256–263. [CrossRef] q
59. Hope, A.L.B.; Jones, C.R. The impact of religious faith on attitudes to environmental issues and Carbon Capture and Storage
(CCS) technologies: A mixed methods study. Technol. Soc. 2014, 38, 48–59. [CrossRef] g
y
60. Carley, S.R.; Krause, R.M.; Warren, D.C.; Rupp, J.A.; Graham, J.D. Early Public Impressions of Terrestrial Carbon Capture and
Storage in a Coal-Intensive State. Environ. Sci. Technol. 2012, 46, 7086–7093. [CrossRef] [PubMed] 60. Carley, S.R.; Krause, R.M.; Warren, D.C.; Rupp, J.A.; Graham, J.D. Early Public Impressions of Terrest
Storage in a Coal-Intensive State. Environ. Sci. Technol. 2012, 46, 7086–7093. [CrossRef] [PubMed] g
61. Dütschke, E.; Wohlfarth, K.; Höller, S.; Viebahn, P.; Schumann, D.; Pietzner, K. Differences in the public perception of CCS in
Germany depending on CO2 source, transport option and storage location. Int. J. Greenh. Gas Control 2016, 53, 149–159. [CrossRef]
62. Williams, R.; Jack, C.; Gamboa, D.; Shackley, S. Decarbonising steel production using CO2 Capture and Storage (CCS): Results of 61. Dütschke, E.; Wohlfarth, K.; Höller, S.; Viebahn, P.; Schumann, D.; Pietzner, K. Differences in the public perception of CCS in
Germany depending on CO2 source, transport option and storage location. Int. J. Greenh. Gas Control 2016, 53, 149–159. [CrossRef] 61. Dütschke, E.; Wohlfarth, K.; Höller, S.; Viebahn, P.; Schumann, D.; Pietzner, K. Differences in the pub
G
d
di
CO
t
t
ti
d t
l
ti
I t J G
h G
C
t
l 201 61. Dütschke, E.; Wohlfarth, K.; Höller, S.; Viebahn, P.; Schumann, D.; Pietzner, K. Differences in the public perception of CCS in
Germany depending on CO2 source, transport option and storage location. Int. J. Greenh. Gas Control 2016, 53, 149–159. [CrossRef]
62. Williams, R.; Jack, C.; Gamboa, D.; Shackley, S. References Carbon Capture and Storage on its way to large-scale deployment: Social acceptance and willingness to pay
in Germany. Energy Policy 2012, 49, 642–651. [CrossRef] 36. Warren, D.C.; Carley, S.; Krause, R.M.; Rupp, J.A.; Graham, D. Predictors of attitudes toward carbon capture and storage using
data on world views and CCS-specific attitudes. Sci. Public Policy 2014, 41, 821–834. [CrossRef] p
y
37. Arning, K.; Heek, J.O.-V.; Linzenich, A.; Kaetelhoen, A.; Sternberg, A.; Bardow, A.; Ziefle, M. Same or different? Insights on public
perception and acceptance of carbon capture and storage or utilization in Germany. Energy Policy 2019, 125, 235–249. [CrossRef]
38. Arning, K.; van Heek, J.; Ziefle, M. Risk perception and acceptance of CDU consumer products in Germany. Energy Procedia 2017,
114, 7186–7196. [CrossRef] 37. Arning, K.; Heek, J.O.-V.; Linzenich, A.; Kaetelhoen, A.; Sternberg, A.; Bardow, A.; Ziefle, M. Same or different? Insights on public
perception and acceptance of carbon capture and storage or utilization in Germany. Energy Policy 2019, 125, 235–249. [CrossRef] 38. Arning, K.; van Heek, J.; Ziefle, M. Risk perception and acceptance of CDU consumer products in G
114, 7186–7196. [CrossRef] 39. Jones, C.R.; Radford, R.L.; Armstrong, K.; Styring, P. What a waste! Assessing public perceptions of Carbon Dioxide Utilisation
technology. J. CO2 Util. 2014, 7, 51–54. [CrossRef] gy
40. Jones, C.R.; Olfe-Kräutlein, B.; Naims, H.; Armstrong, K. The social acceptance of carbon dioxide utilisation: A review and
research agenda. Front. Energy Res. 2017, 5, 11. [CrossRef] g
gy
41. Heek, J.O.-V.; Arning, K.; Sternberg, A.; Bardow, A.; Ziefle, M. Assessing public acceptance of the life cycle of CO2-based fuels:
Does information make the difference? Energy Policy 2020, 143, 111586. [CrossRef] 42. Gölz, S.; Wedderhoff, O. Explaining regional acceptance of the German energy transition by including trust in stakeholders and
perception of fairness as socio-institutional factors. Energy Res. Soc. Sci. 2018, 43, 96–108. [CrossRef] 43. Wennersten, R.; Sun, Q.; Li, H. The future potential for Carbon Capture and Storage in climate change mitigation—an overview
from perspectives of technology, economy and risk. J. Clean. Prod. 2015, 103, 724–736. [CrossRef] p
p
gy
y
44. Seigo, S.L.; Arvai, J.; Dohle, S.; Siegrist, M. Predictors of risk and benefit perception of carbon capt
regions with different stages of deployment. Int. J. Greenh. Gas Control 2014, 25, 23–32. [CrossRef] 45. Siegrist, M.; Cvetkovich, G.; Roth, C. Salient value similarity, social trust, and risk/benefit perception. Risk Anal. 2000, 20, 353–362. Van Os, P. Accelerating low carbon industrial growth through carbon capture, utilization and storage (CC
Technol. 2018, 8, 994–997. [CrossRef] References Kashintseva, V.; Strielkowski, W.; Streimikis, J.; Veynbender, T. Consumer attitudes towards industrial CO2 capture and storage
products and technologies. Energies 2018, 11, 2787. [CrossRef] 67. Kashintseva, V.; Strielkowski, W.; Streimikis, J.; Veynbender, T. Cons
products and technologies. Energies 2018, 11, 2787. [CrossRef] 68. Xenias, D.; Whitmarsh, L. Carbon capture and storage (CCS) experts’ attitudes to and experience with public engagement. Int. J. Greenh. Gas Control 2018, 78, 103–116. [CrossRef] 69. Pihkola, H.; Tsupari, E.; Kojo, M.; Kujanpää, L.; Nissilä, M.; Sokka, L.; Behm, K. Integrated sustainability assessment of
CCS–identifying non-technical barriers and drivers for CCS implementation in Finland. Energy Procedia 2017, 114, 7625–7637. [CrossRef] 70. Ilinova, A.; Cherepovitsyn, A.; Evseeva, O. Stakeholder Management: An Approach in CCS Projects. Resources 2018, 7, 83. [CrossRef] 71. Thomas, G.; Pidgeon, N.; Roberts, E. Ambivalence, naturalness and normality in public perceptions of ca
in biomass, fossil energy, and industrial applications in the United Kingdom. Energy Res. Soc. Sci. 2018 72. Van Os, P. Accelerating low carbon industrial growth through carbon capture, utilization and storage (CCUS). Greenh. Gases Sci. Technol. 2018, 8, 994–997. [CrossRef] Sustainability 2021, 13, 12278 29 of 29 73. Serdoner, A. European Environmental Advocacy Coalitions: Environmental Non-Governmental Perceptions of Carbon Capture
and Storage in Energy Intensive Industries. Masters’s Thesis, University of Graz, Graz, Austria, 2019. g
gy
y
74. Boomsma, C.; ter Mors, E.; Jack, C.; Broecks, K.; Buzoianu, C.; Cismaru, D.M.; Peuchen, R.; Piek, P.; Schumann, D.; Shackley,
S. Community compensation in the context of Carbon Capture and Storage: Current debates and practices. Int. J. Greenh. Gas
Control 2020, 101, 103128. [CrossRef] ,
,
[
]
75. Kojo, M.; Innola, E. Carbon Capture and Storage in the Finnish Print Media. Risk Hazards Crisis Public Policy 2017, 8, 113–146. [CrossRef] 76. Haikola, S.; Hansson, A.; Anshelm, J. From polarization to reluctant acceptance–bioenergy with carbon capture and storage
(BECCS) and the post-normalization of the climate debate. J. Integr. Environ. Sci. 2019, 16, 45–69. [CrossRef] 77. Rodriguez, E.; Lefvert, A.; Fridahl, M.; Grönkvist, S.; Haikola, S.; Hansson, A. Tensions in the energy transition: Swedish and
Finnish company perspectives on bioenergy with carbon capture and storage. J. Clean. Prod. 2020, 280, 124527. [CrossRef] ez, E.; Lefvert, A.; Fridahl, M.; Grönkvist, S.; Haikola, S.; Hansson, A. Tensions in the energy transition: S 77. Rodriguez, E.; Lefvert, A.; Fridahl, M.; Grönkvist, S.; Haikola, S.; Hansson, A. References Tensions in the energy transition: Swedish and
Fi
i h
ti
bi
ith
b
t
d t
J Cl
P
d 2020 280 124527 [C
R f] 78. Alcalde, J.; Heinemann, N.; Mabon, L.; Worden, R.H.; de Coninck, H.; Robertson, H.; Maver, M.; Ghanbari, S.; Swennenhuis, F.;
Mann, I. Acorn: Developing full-chain industrial carbon capture and storage in a resource- and infrastructure-rich hydrocarbon
province. J. Clean. Prod. 2019, 233, 963–971. [CrossRef] 79. Yu, H.; Reiner, D.; Chen, H.; Mi, Z. A Comparison of Public Preferences for Different Low-Carbon Energy Technologies: Support for CCS,
Nuclear and Wind Energy in the United Kingdom; Energy Policy Research Group (EPRG) Working Paper 1810, Cambridge Working
Paper in Economics 1826; JSTOR: Cambridge, UK, 2018; Available online: https://www.jstor.org/stable/pdf/resrep30335.pdf
(accessed on 6 November 2020). 80. Wüstenhagen, R.; Wolsink, M.; Bürer, M.J. Social acceptance of renewable energy innovation: An introduction to the concept. Energy Policy 2007, 35, 2683–2691. [CrossRef] J.; Vanclay, F. Community engagement and social licence to operate. Impact Assess. Proj. Apprais. 2014, 32 82. Convention on Biological Diversity. Biodiversity and Climate Change; No. CBD/SBSTTA/23/3; UNEP: Montreal, QC, Canada,
2019; Available online: https://www.cbd.int/doc/c/326e/cf86/773f944a5e06b75dfc5866bf/sbstta-23-03-en.pdf (accessed on 1
November 2021). 83. Tokushige, K.; Akimoto, K.; Tomoda, T. Public acceptance and risk-benefit perception of CO2 geological storage for global
warming mitigation in Japan. Mitig. Adapt. Strateg. Glob. Change 2007, 12, 1237–1251. [CrossRef] . Geological Storage of CO2—Long Term Security Aspects; Springer International Publishing: Geotechnologien, 84. Liebscher, A.; Münch, U. Geological Storage of CO2—Long Term Security Aspects; Springer International Pub
Switzerland, 2015. 85. Markewitz, P.; Zhao, L.; Robinius, M. Technologiebericht 2.3 CO2—Abscheidung und Speicherung (CCS), Wuppertal, Karlsruhe,
Saarbrücken: Wuppertal Institut Für Klima, Umwelt Und Energie. 2017. Available online: https://epub.wupperinst.org/files/70
51/7051_CCS.pdf (accessed on 1 November 2021). 86. Pietzner, K.; Schumann, D.; Tvedt, S.D.; Torvatn, H.Y.; Næss, R.; Reiner, D.M.; Anghel, S.; Cismaru, D.; Constantin, C.; Daamen,
D.D. Public awareness and perceptions of carbon dioxide capture and storage (CCS): Insights from surveys administered to
representative samples in six European countries. Energy Procedia 2011, 4, 6300–6306. [CrossRef] 87. Brondízio, E.S.; Settele, J.; Díaz, S.; Ngo, H.T. IPBES: Global Assessment Report of the Intergovernmental Science-Policy Platform on
Biodiversity and Ecosystems Services; IPBES Secretariat: Bonn, Germany, 2019. 88. Available online: https://iea.blob.core.windows.net/assets/0d0b4984-f391-44f9-854f-fda1ebf8d8df/Transforming_Industry_
through_CCUS.pdf (accessed on 1 November 2021). 88. Available online: https://iea.blob.core.windows.net/
through_CCUS.pdf (accessed on 1 November 2021).
|
https://openalex.org/W4387053822
|
https://cnjournal.biomedcentral.com/counter/pdf/10.1186/s41016-023-00341-4
|
English
| null |
Expression of TXLNA in brain gliomas and its clinical significance: a bioinformatics analysis
|
Chinese neurosurgical journal
| 2,023
|
cc-by
| 6,675
|
© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which
permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the
original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or
other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line
to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory
regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this
licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecom-
mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Abstract Background To analyze the expression of TXLNA in brain gliomas and its clinical significance. yi
Methods Gene Expression Profiling Interactive Analysis（GEPIA）and Chinese Glioma Genome Atlas（CGGA）
databases were retrieved as the methods. To assess the disparity between TXLNA expression in glioma and normal
brain tissue. The Kaplan-Meier survival curve was employed to preliminarily evaluate the survival curves of the high
and low expression groups, this was done for investigate the correlation between TXLNA expression level and the sur-
vival and prognosis of glioma. A Cox proportional regression risk model of multivariate nature was employed to evalu-
ate the elements impacting the survival and prognosis of glioma. Gene pool enrichment analysis（GSEA）was used
to investigate the related function of TXLNA in glioma. A Pearson correlation test and co-expression analysis were
employed to identify the genes most associated with TXLNA expression. Result The enrichment analysis results were observably enriched in signal pathways for instance the cell cycle
and completion and coordination cascade pathways, and it is evident that high expression of TXLNA in gliomas
is related to a poor survival and a bad patient prognosis, thus making it an independent prognostic factor for gliomas. Genes such as STK40 and R1MS1 are significantly correlated with TXLNA, playing a synergistic or antagonistic role. Conclusions The prognosis of GBM patients is strongly linked to the high expression of TXLNA, which may be
a viable therapeutic target for curbing cancer progression and creating new immunotherapies for GBM. Keywords Glioma, TXLNA, Gene expression, Bioinformatics analysis (GBM) is the most deadly, accounting for 70–75% and
having a median overall survival of only 14–17 months
[2]. Currently, the treatment options for GBM are mainly
surgical, with radiotherapy and chemotherapy added as
an option. In addition, improvements in surgical micros-
copy, high-resolution imaging, fluorescence guided sur-
gery, and neuronavigation are more and more used in the
therapy of glioma [3]. However, due to its rapid spread,
extensive infiltration and drug resistance, the postop-
erative recurrence rate is still high and the prognosis of
patients is in a dismal state [4]. Thanks to cellular and
biomolecular studies, the molecular processes of glioma
and metastasis and novel targets for tumor therapy have
been widely studied [5]. Currently, targeted therapy
is a potential way to treat tumors. By exploring novel Chinese Neurosurgical Journal Chinese Neurosurgical Journal Hu et al. Chinese Neurosurgical Journal (2023)
https://doi.org/10.1186/s41016-023-00341-4 Open Access Expression of TXLNA in brain gliomas and its
clinical significance: a bioinformatics analysis Bowen Hu1, Desheng Chen1, Yang Li1, Shan Yu2, Liangwen Kuang1, Xinqi Ma1, Qingsong Yang1, Ke He1,
Yan Zhao1, Guangzhi Wang1* and Mian Guo1* Backgroundh The two main subgroups of primary intracranial tumors,
diffuse and non-diffuse gliomas, are the most prevalent
[1]. Of all the diffuse gliomas diagnosed, glioblastoma *Correspondence:
Guangzhi Wang
h04863@hrbmu.edu.cn
Mian Guo
guomian@hrbmu.edu.cn
1 Department of Neurosurgery, The Second Affiliated Hospital
of Harbin Medical University, 246 Xuefu Road, Nangang, Harbin 150086,
Heilongjiang Province, China
2 Department of Pathology, The Second Affiliated Hospital of Harbin
Medical University, 246 Xuefu Road, Nangang, Harbin 150086,
Heilongjiang Province, China *Correspondence:
Guangzhi Wang
h04863@hrbmu.edu.cn
Mian Guo
guomian@hrbmu.edu.cn
1 Department of Neurosurgery, The Second Affiliated Hospital
of Harbin Medical University, 246 Xuefu Road, Nangang, Harbin 150086,
Heilongjiang Province, China
2 Department of Pathology, The Second Affiliated Hospital of Harbin
Medical University, 246 Xuefu Road, Nangang, Harbin 150086,
Heilongjiang Province, China Methods
GEPIA GEPIA, as a web server for cancer and normal gene
expression and interaction analysis, is widely used by
scholars around the world. It was used in this study
to investigate the differential expression of TXLNA in
glioma and normal brain tissue. Then we used one-way
ANOVA to detect the survival curve of TXLNA high and
low expression groups in glioma cells. GSEA GSEA Gene set Enrichment Analysis (GSEA) is a com-
mon and effective means to detect gene function and
signaling pathways, and it is also a method to reveal
genomic expression data. We divided the samples
obtained from the CGGA database into two groups: high
TXLNA expression and low TXLNA expression. P value
less than 0.05, FDR value less than 0.25 is significant. Gliomas exhibiting a high expression of TXLNA are linked
to a poor prognosish The expression of TXLNA in glioblastoma and low-grade
glioma was observably higher than that of normal brain
tissue (P < 0.05, Fig. 1a). Moreover, as malignancy deep-
ens, the expression of TXLNA is also rising. A poor prog-
nosis in glioma patients is associated with a high TXLNA
expression (p < 0.05, Fig. 1b). TXLNA is highly expressed in gliomas and reduces overall
survival timef According to the expression difference of TXLNA,
We split the samples into two distinct groups, one
with high TXLNA expression and the other with low
TXLNA expression, to explore the effects of TXLNA
on glioma patients. Survival kits and questionnaires
were employed to assess the distinctions between the
two groups, and the outcomes showed that the survival
rate of those in the high and low expression groups had
decreased over time, and the survival disparity between
the two groups was highly significant (p < 0.001). The
TXLNA high expression group had a 5-year sur-
vival rate of 16.0%(95% CI [0.1219–0.211]), while the
TXLNA low expression group had a 5-year survival
rate of 61.4%(95% CI [0.563–0.670]) (Fig. 2a), as indi-
cated by statistical analysis. Verification of TXLNA Comprehensive analysis of transcriptome data of glioma
samples from CGGA database To discuss the prognostic value of TXLNA in GBM
patients, the Kaplan Meier method and Cox regression
model were utilized. GSEA was employed to forecast
the related biological activities and pathways of TXLNA
in glioma. Employing a Pearson correlation test and co
expression analysis, the top five genes most closely rel-
evant to TXLNA expression were identified, with the
highest correlations being both positive and negative. Therefore, the spe-
cific function of TXLNA in glioma, whether it accelerates
the pathological process of glioma or regards as a target
for clinical therapy, still requires a large amount of data
analysis. This study explored the molecular and clinical
characteristics of TXLNA in gliomas through bioinfor-
matics analysis, and reached corresponding conclusions. therapeutic objectives, targeted medications can be for-
mulated and the outlook of patients enhanced. TXLNA
(taxilin α) is a binding partner of the syntaxin family. Its
alias in NCBI is also called interleukin 14 (IL-14), which
is considered to be the key factor to coordinate the vesic-
ular transport within cells. As we all know, vesicular
transport is involved in multiple processes of eukaryotic
cell proliferation, and its function also suggests that this
gene may be involved in tumor expression [6]. More than
that, a few Studies have established TXLNA’s existence
and manifestation in hepatocellular carcinoma, renal cell
carcinoma, and pancreatic tumor cells [7, 8]. In addition,
Sueli M et al. conducted real-time fluorescence quantita-
tive PCR analysis of TXLNA genes using different grade
astrocytic tumor samples in an experiment, confirming
that their expression was higher compared to non-tumor
CNS tissues [9]. Until now, there has been a dearth of
systematic and thorough research into the bioinformatics
analysis of TXLNA about expression difference in brain
gliomas, their clinical importance, and their mechanism
of action, despite PCR analysis of TXLNA genes in gli-
oma patients having been conducted. Therefore, the spe-
cific function of TXLNA in glioma, whether it accelerates
the pathological process of glioma or regards as a target
for clinical therapy, still requires a large amount of data
analysis. This study explored the molecular and clinical
characteristics of TXLNA in gliomas through bioinfor-
matics analysis, and reached corresponding conclusions. © The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which
permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the
original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or
other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line
to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory
regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this
licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecom-
mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Page 2 of 10 screening, 749 patients were eventually included in our
research. therapeutic objectives, targeted medications can be for-
mulated and the outlook of patients enhanced. TXLNA
(taxilin α) is a binding partner of the syntaxin family. Its
alias in NCBI is also called interleukin 14 (IL-14), which
is considered to be the key factor to coordinate the vesic-
ular transport within cells. As we all know, vesicular
transport is involved in multiple processes of eukaryotic
cell proliferation, and its function also suggests that this
gene may be involved in tumor expression [6]. More than
that, a few Studies have established TXLNA’s existence
and manifestation in hepatocellular carcinoma, renal cell
carcinoma, and pancreatic tumor cells [7, 8]. In addition,
Sueli M et al. conducted real-time fluorescence quantita-
tive PCR analysis of TXLNA genes using different grade
astrocytic tumor samples in an experiment, confirming
that their expression was higher compared to non-tumor
CNS tissues [9]. Until now, there has been a dearth of
systematic and thorough research into the bioinformatics
analysis of TXLNA about expression difference in brain
gliomas, their clinical importance, and their mechanism
of action, despite PCR analysis of TXLNA genes in gli-
oma patients having been conducted. CGGAh The Chinese Glioma Genome Atlas contains functional
genomics data of 2000 Chinese glioma samples. This
article primarily employs RNA sequencing data from
genomic (1018 cases) and clinical information, both
of which are found in the CGGA database. The clinical
data include the gender, age, radiation and chemother-
apy status of glioma patients, complete follow-up data,
histopathological classification, different WHO grades,
primary or recurrent gliomas. After the above data were
downloaded, the sequencing data were batch corrected,
and the clinical data such as expression data and sur-
vival data were further integrated. After filtering and Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Page 3 of 10 Fig. 1 TXLNA is highly expressed in gliomas and is associated with poor prognosis. A The expression of TXLNA in GBM and LGG was higher
than that in normal tissues in the GEPIA database. B Glioma patients with high TXLNA expression have shorter survival times than those with low
expression in the GEPIA database Fig. 1 TXLNA is highly expressed in gliomas and is associated with poor prognosis. A The expression of TXLNA in GBM and LGG was higher
than that in normal tissues in the GEPIA database. B Glioma patients with high TXLNA expression have shorter survival times than those with low
expression in the GEPIA database Fig. 2 The Kaplan-Meier survival curve and The ROC curve. A Highly expressed TXLNA leads to shorter overall survival time for patients with glioma. B ROC curve shows that using TXLNA as a prognostic marker is valuable Fig. 2 The Kaplan-Meier survival curve and The ROC curve. A Highly expressed TXLNA leads to shorter overall survival time for patients with glioma. B ROC curve shows that using TXLNA as a prognostic marker is valuable curves all had AUCs that surpassed 0.7 (Fig. 2b). More-
over, the area beneath the ROC curve (AUC) was also
higher than 0.7, suggesting TXLNA expression is reli-
able in forecasting survival time. expression levels’ reliability in predicting patient sur-
vival time was further accomplished by employing
the receiver operating characteristic curve (ROC). The prognosis model’s 1-year, 3-year, and 5-year ROC Page 4 of 10 Hu et al. Chinese Neurosurgical Journal (2023) 9:27 The prognosis of glioma patients can be predicted
independently by the expression of TXLNA GBM patients. The clinical features of it are also closely
connected with the prognosis. To further explore the
relationship between TXLNA and clinical factors, the
Wilcox test and Kruskal method were used by us. A cor-
relation between TXLNA expression and tumor grade
was demonstrated, with the expression of TXLNA gradu-
ally augmenting with the augmentation of tumor grade
(p < 0.001). Additionally, the expression of TXLNA
was linked to the age of the patients, with those aged
> 41 years exhibiting a greater gene expression than
those aged < 41 years (p = 0.001). Then, the correla-
tion between TXLNA expression and the IDH mutation
means that there is a link. What is more, TXLNA expres-
sion in wild-type tumors of IDH was distinctly higher
than that of mutant genes (p < 0.001). TXLNA expression
and recurrent status were also proved closely related by
analysis (p = 0.019), with primary tumors displaying a
lesser TXLNA expression than recurrent status. TXLNA
expression was correlated with 1p19q deletion, and its We compared TXLNA gene expression, age, and IDH
mutations to survival time and survival status in order
to assess if TXLNA could be regarded as a risk factor
for predicting GBM patients’ prognosis. A Cox regres-
sion model was used to evaluate the relationship between
TXLNA expression, clinical characteristics and progno-
sis, from which we found that tumor recurrence, age, and
IDH mutation were closely related to the survival rate of
GBM patients. Furthermore, we confirmed that TXLNA
could be regarded as an independent risk factor in GBM
patients by univariate and multivariate Cox analysis
(Fig. 3). lationship between clinical features and prognosis of patients with glioma. A Univariate analysis. B Multivariate analysis Coexpression analysis Pearson’s correlation test was employed to further eluci-
date TXLNA’s part in the pathogenesis of gliomas, and
TXLNA related genes were pinpointed. Filter and screen
out the 10 genes most relevant to TXLNA, including the
first 5 genes that are positively correlated, namely STK40,
NADK, PHC2, AK2, and SF3A3, as well as the first 5
genes that are negatively correlated, including R1MS1,
TUB, AMER3, SVOP, and AJRNL1. From Figs. 6 and 7, it
can be seen that TXLNA perhaps accelerate the expres-
sion of positively correlated genes, or these co expressed
positive correlated genes together with TXLNA affect
specific pathophysiological processes, thereby promoting
the occurrence and progress of GBM. Contrarily, TXLNA
may inhibit the expression of negatively correlated genes,
or their functions may be antagonistic to each other. Relationship between TXLNA and different clinical
characteristicsh Through the analysis of previous studies, we concluded
that TXLNA is an independent prognostic factor for Fig. 3 Relationship between clinical features and prognosis of patients with glioma. A Univariate analysis. B Multivariate analysis Fig. 3 Relationship between clinical features and prognosis of patients with glioma. A Univariate analysis. B Multivariate analysis Fig. 3 Relationship between clinical features and prognosis of patients with glioma. A Univariate analysis. B Multivariate analysis Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Page 5 of 10 Fig. 4 Relationship between TXLNA and clinical characteristics. A PRS type. B Age. C Grade. D Chemotherapy. E IDH mutation. F 1p/19q codeletion
G Histology Fig. 4 Relationship between TXLNA and clinical characteristics. A PRS type. B Age. C Grade. D Chemotherapy. E IDH mutation. F 1p/19q codeletion. G Histology Fig. 4 Relationship between TXLNA and clinical characteristics. A PRS type. B Age. C Grade. D Chemotherapy. E IDH mutation. F 1p/19q codeletion. G Histology Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Page 6 of 10 Therefore, these pathways can be considered as potential
pathways for TXLNA regulation in glioma. expression in 1p19q deletion was lower than that in wild
type without 1p19q deletion (p < 0.001); Finally, TXLNA
expression is also associated with chemotherapy, and
analysis suggests that TXLNA expression in non-chem-
otherapy recipients is lower than that in chemotherapy
recipients (p < 0.001)(Fig. 4a–g). The potential pathway of TXLNA in regulating
the malignant biological behavior of glioma Employing the GSEA technique, we pinpointed the
biological functions linked to TXLNA. By identifying
TXLNA enrichment pathways, we can indirectly under-
stand what pathways TXLNA regulates to affect the
occurrence of glioma. We divided the sample data into
two groups according to the high and low expression of
TXLNA. The consequences showed that the expression
of TXLNA was relevant to a variety of tumor interrelated
pathways, including the cell cycle path, completion and
coaggregation casca path, receiver interaction path, focal
adhesion path, leishmania infection path, ribosome path,
splice some path, and lupus erythematosus path (Fig. 5). Fig. 5 Significantly enriched pathways with multiple GSEA Fig. 5 Significantly enriched pathways with multiple GSEA Page 7 of 10
Hu et al. Chinese Neurosurgical Journal (2023) 9:27
Discussion
TXLNA is a significant cytokine, It is also known as
interleukin 14(IL-14) in NCBI, meanwhile, it is also went
by the name of high-molecular-weight B cell growth
factor(HMW-BCGF). It is primarily generated by T lym-
phocytes and can trigger the proliferation of activated
Fig. 6 Gene expression heat map and correlations for TXLNA co-expressed genes
Fig. 7 The co-expressed network of TXLNA. A The circos plot was constructed by 10 genes most related to TXLNA expression, including 5 positively
related genes and 5 negatively related genes (p < 0.05). B Co-expression relationship of 10 genes in TXLNA Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Page 7 of 10 Fig. 6 Gene expression heat map and correlations for TXLNA co-expressed genes Fig. 6 Gene expression heat map and correlations for TXLNA co-expressed genes Fig. 6 Gene expression heat map and correlations for TXLNA co-expressed genes Fig. 7 The co-expressed network of TXLNA. A The circos plot was constructed by 10 genes most related to TXLNA expression, including 5 positively
related genes and 5 negatively related genes (p < 0.05). B Co-expression relationship of 10 genes in TXLNA Fig. 7 The co-expressed network of TXLNA. A The circos plot was constructed by 10 genes most related to TXLNA expression, including 5 positively
related genes and 5 negatively related genes (p < 0.05). B Co-expression relationship of 10 genes in TXLNA by the name of high-molecular-weight B cell growth
factor(HMW-BCGF). It is primarily generated by T lym-
phocytes and can trigger the proliferation of activated Discussion TXLNA is a significant cytokine, It is also known as
interleukin 14(IL-14) in NCBI, meanwhile, it is also went Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Page 8 of 10 Page 8 of 10 Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Hu et al. Chinese Neurosurgical Journal (2023) 9:27 B cells, impede immunoglobulin secretion, and selec-
tively enlarge certain B cell subsets. Studies of antibod-
ies to HMW-BCGF and its receptors have revealed that,
despite its production by T cells and some malignant B
cells, it primarily impacts both normal and malignant B
cells [10]. Confirmed to be involved in Ca2+ dependent
exocytosis of neuroendocrine cells, TXLNA has a vital
role in intracellular material transport, which is essen-
tial for tissue structure and cell function. The soluble
N-ethylmaleimide-sensitive factor attachment protein
receptor (SNARE) mechanism plays a dominant role in
intracellular vesicle transport. Although its specific mode
of action and function are still unknown, TXLNA, as a
novel binding partner of the synthetic protein family, has
been approved to be involved in the control of the forma-
tion of SNARE complexes [6]. This function of TXLNA
suggests that it may participate in the gene expression of
tumor cells. Its role also could be to either accelerate or
impede the growth and emergence of tumor cells.f for glioma patients. Furthermore, the development of
glioma is not caused by a single gene, but rather by the
disruption of the equilibrium between multiple carci-
nogenic and tumor suppressor elements. Unveiling the
gene’s mechanism of action in glioma necessitates the
examination of other genes associated with it, as well as
the cellular pathways that are implicated. Therefore, we used Cox regression model to conduct
univariate and multivariate analysis, and found that
TXLNA can still be an independent risk factor to fore-
cast the prognosis of GBM patients after eliminating
the impact of other elements. In addition, other clini-
cal features, including PRS type, grade, age, chemother-
apy, IDH mutation status, and 1p19q co deletion status,
could also be independent risk factors. Utilizing gene set
enrichment analysis (GSEA), we investigated TXLNA’s
expression and discovered its association with multi-
ple tumor-related pathways, such as the cell cycle path,
completion and coaggregation cascade path, receiver
interaction path, focal adhesion path, leishmania infec-
tion path, ribosome path, splice some path, and lupus
erythematosus path. Discussion Recent articles have explored the
correlation between certain pathways and glioma’s bio-
logical behavior. COL1A2 inhibition attenuates GBM
proliferation which is depended on accelerating cell cycle
arrest [13]. The casca pathway of coagulation could be a
critical factor in immunotherapy and anti-cancer immu-
nity, not only aiding in the elimination of tumors but also
stimulating tumor expansion [14]. The Kangliu pill(KLP)
has anti-tumor activity in glioma, which may be related
to receptor interaction pathway [15]. The adhesion sign-
aling pathway is activated by mda-9/syntenin, which in
turn induces glioma migration through adhesion kinase
(FAK) [16]. Pathways of this kind are a major factor in
the pathology of glioma, stimulating malignant biological
activities such as proliferation, migration, and invasion
of glioma cells. However, there is still a lack of laboratory
data to support the relationship between some pathways
and TXLNA expression in glioma cells or tumor cells. However, reports have shown that TXLNA has differ-
ent functions in different types of tumors. TXLNA, for
example, is a cancer suppressor gene in pancreatic can-
cer, yet it is a promoter of tumors in hepatocellular car-
cinoma and renal cell carcinoma, thus inducing their
emergence and development. It was proposed by Nat-
suko Ohtomo et al. that the TXLNA expression is linked
to the augmented proliferation and poorly differentiated
histological evaluation of hepatocellular carcinoma [7]. Tomoko Mashidori 1 et al. found that the metastatic and
invasive capacity of renal cell carcinoma was revealed
to be augmented by a high expression of TXLNA [11]. However, not high TXLNA expression in all tumors is
associated with poor prognosis. In the research on pan-
creatic cancer, it was concluded that the high expression
of TXLNA suggests a favorable prognosis for patients
[8]. In addition, there are relevant studies in non-solid
tumors. Studies have established that in invasive B cell
non-Hodgkin’s lymphoma (NHL-B), both autocrine and
paracrine IL-14 may be an important factor in its rapid
proliferation [12]. Finally, Pearson correlation test and co expression
analysis were employed to identify the 10 genes most
relevant with TXLNA expression, of which 5 were
found to be positively correlated—STK40, NADK,
PHC2, AK2, and SF3A3. These genes’ pathophysiologi-
cal processes have been established to be strongly cor-
related with the biological activity of tumors. Belonging
to the Tribbles pseudokinases family, STK40 is seen as
a marker of cancer progression [17]. Conclusion
TXLNA TXLNA expression in glioma tissues is far greater than
in normal tissues, and its upsurge is associated with a
reduced likelihood of survival and a dismal outlook. It
can be employed as a distinct prognostic indicator for
glioma patients. Its mechanism of action is significantly
enriched in signal pathways such as the cell cycle path
and the completion and coordination cascade path. STK40, NADK, PHC2, AK2, and SF3A3 are positive cor-
relation genes for TXLNA, while R1MS1, TUB, AMER3,
SVOP, and AJRNL1 are negative correlation genes for
TXLNA. Our findings reveal a correlation between GBM
and malignant clinical features. Our discoveries furnish
novel diagnostic and prognostic indicators for further
investigation. 4. van Solinge TS, Nieland L, Chiocca EA, Broekman MLD. Advances in local
therapy for glioblastoma - taking the fight to the tumour. Nat Rev Neurol. 2022;18(4):221–36. https://doi.org/10.1038/s41582-022-00621-0. (Epub
2022 Mar 11 PMID: 35277681). 4. van Solinge TS, Nieland L, Chiocca EA, Broekman MLD. Advances in local
therapy for glioblastoma - taking the fight to the tumour. Nat Rev Neurol. 2022;18(4):221–36. https://doi.org/10.1038/s41582-022-00621-0. (Epub
2022 Mar 11 PMID: 35277681). 5. Yang K, Wu Z, Zhang H, Zhang N, Wu W, Wang Z, Dai Z, Zhang X, Zhang
L, Peng Y, Ye W, Zeng W, Liu Z, Cheng Q. Glioma targeted therapy:
insight into future of molecular approaches. Mol Cancer. 2022;21(1):39. https://doi.org/10.1186/s12943-022-01513-z. PMID:35135556;PMCID:
PMC8822752. 5. Yang K, Wu Z, Zhang H, Zhang N, Wu W, Wang Z, Dai Z, Zhang X, Zhang
L, Peng Y, Ye W, Zeng W, Liu Z, Cheng Q. Glioma targeted therapy:
insight into future of molecular approaches. Mol Cancer. 2022;21(1):39. https://doi.org/10.1186/s12943-022-01513-z. PMID:35135556;PMCID:
PMC8822752. 6. Nogami S, Satoh S, Nakano M, Shimizu H, Fukushima H, Maruyama A,
Terano A, Shirataki H. Taxilin; a novel syntaxin-binding protein that is
involved in Ca2+-dependent exocytosis in neuroendocrine cells. Genes
Cells. 2003;8(1):17–28. https://doi.org/10.1046/j.1365-2443.2003.00612.x. (PMID: 12558796). 7. Ohtomo N, Tomiya T, Tanoue Y, Inoue Y, Nishikawa T, Ikeda H, Seyama Y,
Kokudo N, Shibahara J, Fukayama M, Koike K, Shirataki H, Fujiwara K. Expres-
sion of α-taxilin in hepatocellular carcinoma correlates with growth activity
and malignant potential of the tumor. Int J Oncol. 2010;37(6):1417–23. https://doi.org/10.3892/ijo_00000793. (PMID: 21042709). 7. Ohtomo N, Tomiya T, Tanoue Y, Inoue Y, Nishikawa T, Ikeda H, Seyama Y,
Kokudo N, Shibahara J, Fukayama M, Koike K, Shirataki H, Fujiwara K. Expres-
sion of α-taxilin in hepatocellular carcinoma correlates with growth activity
and malignant potential of the tumor. References 1. Wesseling P, Capper D. WHO 2016 Classification of gliomas. Neuropathol
Appl Neurobiol. 2018;44(2):139–50. https://doi.org/10.1111/nan.12432. (PMID: 28815663). 1. Wesseling P, Capper D. WHO 2016 Classification of gliomas. Neuropathol
Appl Neurobiol. 2018;44(2):139–50. https://doi.org/10.1111/nan.12432. (PMID: 28815663). 1. Wesseling P, Capper D. WHO 2016 Classification of gliomas. Neuropathol
Appl Neurobiol. 2018;44(2):139–50. https://doi.org/10.1111/nan.12432. (PMID: 28815663). 2. Molinaro AM, Taylor JW, Wiencke JK, Wrensch MR. Genetic and molecular
epidemiology of adult diffuse glioma. Nat Rev Neurol. 2019;15(7):405–17. 3. Weller M, van den Bent M, Preusser M, Le Rhun E, Tonn JC, Minniti G,
Bendszus M, Balana C, Chinot O, Dirven L, French P, Hegi ME, Jakola AS,
Platten M, Roth P, Rudà R, Short S, Smits M, Taphoorn MJB, von Deimling
A, Westphal M, Soffietti R, Reifenberger G, Wick W. EANO guidelines on
the diagnosis and treatment of diffuse gliomas of adulthood. Nat Rev Clin
Oncol. 2021;18(3):170–86. Funding Funding
This endeavor was backed by the National Natural Science Foundation of
China (82173384 and 81773161) Availability of data and materials
All the data in this study were obtained from Chinese Glioma Genome Atlas
dataset (CGGA; http://www.cgga.org.cn/). Availability of data and materials
All the data in this study were obtained from Chinese Glioma Genome Atlas
dataset (CGGA; http://www.cgga.org.cn/). Availability of data and materials
All the data in this study were obtained from Chinese Glioma Genome Atlas
dataset (CGGA; http://www.cgga.org.cn/). Availability of data and materials
All the data in this study were obtained from Chinese Glioma Genome Atlas
dataset (CGGA; http://www.cgga.org.cn/). Competing interests The authors declare that they have no competing interests. The authors declare that they have no competing interests. Received: 7 April 2023 Accepted: 29 August 2023 Received: 7 April 2023 Accepted: 29 August 2023 Consent for publication
Not applicable. Consent for publication
Not applicable. Authors’ contributions Authors contributions
These authors contributed equally to the work. Discussion NADK and KHK,
two genes responsible for metabolic enzymes, are inac-
tivated in animal models, thus inhibiting the growth
of tumors with KRAS mutations [18]. In an epigenetic
study of prostate cancer cells, it was found that R1881
treated cells had higher PHC2 methylation [19]. This Nevertheless, the role of TXLNA in glioma is still a
mystery. To uncover its expression and clinical impor-
tance, we conducted bioinformatics studies on GEPIA
and CGGA databases to compare the expression and
prognostic analysis of TXLNA. A marked divergence in
TXLNA expression between glioma and normal brain
tissue was uncovered by our findings, and a negative rela-
tionship between TXLNA expression and OS in glioma
patients was also observed. The ROC curve confirms that
TXLNA expression is reliable in predicting survival time. The occurrence and development of tumors, though not
due to a single cause, is still influenced by many factors;
thus, it is uncertain if TXLNA can be a distinct risk factor Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Page 9 of 10 indicates that PHC2 methylation is associated with the
occurrence and progress of prostate cancer. The over-
expressed of AK2 and other genes was reported to be
a factor in the growth of breast cancer that was inva-
sive [20]. The interplay between CircSCAP and SF3A3
inhibits the malignancy of non-small cell lung cancer
by activating p53 signaling pathways [21]. In addition,
we have also screened five negatively correlated genes,
including RIMS1, TUB, AMER3, SVOP, and ATRNL1. Among them, the expression of RIMS1 was also dis-
tinctly downregulated in Adamantinomatous crani-
opharyngioma cancer samples [22]. Moreover, TUB
low expression in circulating tumor cells inversely
influenced patients’ OS as independent prognostic fac-
tors [23]. What is more, AMER3 variants modify the
U-shaped association of urinary total hydroxyphenan-
threne with fasting plasma glucose [24], however, the
association of this gene and tumor is rarely reported. A
study conducted by Jingwei Zhao identified five Differ-
ential methylated genes as critical prognostic biomark-
ers in GBM progression, including the SVOP [25]. A
retrospective study of 454 cases with solid pseudopapil-
lary neoplasm of the pancreas uncovered that ATRNL1
is one of the top three frequently mutated genes [26]. In
general, the occurrence and progress of GBM is a very
intricate biological course. Discussion TXLNA’s involvement in the
glioma regulatory network is demonstrated through its
interaction with cancer genes and cancer suppressor
genes. indicates that PHC2 methylation is associated with the
occurrence and progress of prostate cancer. The over-
expressed of AK2 and other genes was reported to be
a factor in the growth of breast cancer that was inva-
sive [20]. The interplay between CircSCAP and SF3A3
inhibits the malignancy of non-small cell lung cancer
by activating p53 signaling pathways [21]. In addition,
we have also screened five negatively correlated genes,
including RIMS1, TUB, AMER3, SVOP, and ATRNL1. Among them, the expression of RIMS1 was also dis-
tinctly downregulated in Adamantinomatous crani-
opharyngioma cancer samples [22]. Moreover, TUB
low expression in circulating tumor cells inversely
influenced patients’ OS as independent prognostic fac-
tors [23]. What is more, AMER3 variants modify the
U-shaped association of urinary total hydroxyphenan-
threne with fasting plasma glucose [24], however, the
association of this gene and tumor is rarely reported. A
study conducted by Jingwei Zhao identified five Differ-
ential methylated genes as critical prognostic biomark-
ers in GBM progression, including the SVOP [25]. A
retrospective study of 454 cases with solid pseudopapil-
lary neoplasm of the pancreas uncovered that ATRNL1
is one of the top three frequently mutated genes [26]. In
general, the occurrence and progress of GBM is a very
intricate biological course. TXLNA’s involvement in the
glioma regulatory network is demonstrated through its
interaction with cancer genes and cancer suppressor
genes. Declarations Ethics approval and consent to participate
This paper is a bioinformatics analysis that does not involve clinical and animal
experiments and does not require ethical approval. Acknowledgements We are grateful to all the medical staff in the Fifth Neurosurgery Ward of
Harbin Medical University for supporting this study. Authors’ contributions
These authors contributed equally to the work. Abbreviations
GEPIA
Gene Expression Profiling Interactive Analysis
CGGA
Chinese Glioma Genome Atlas
GSEA
Gene pool enrichment analysis
GBM
Glioblastoma Conclusion
TXLNA Int J Oncol. 2010;37(6):1417–23. https://doi.org/10.3892/ijo_00000793. (PMID: 21042709). Abbreviations
GEPIA
Gene Expression Profiling Interactive Analysis
CGGA
Chinese Glioma Genome Atlas
GSEA
Gene pool enrichment analysis
GBM
Glioblastoma 8. Lv S, Zhang G, Xie L, Yan Z, Wang Q, Li Y, Zhang L, Han Y, Li H, Du Y, Yang Y,
Guo X. High TXLNA expression predicts favourable outcome for pancre-
atic adenocarcinoma patients. Biomed Res Int. 2020;25(2020):2585862. https://doi.org/10.1155/2020/2585862. PMID:32185195;PMCID:
PMC7060861. 8. Lv S, Zhang G, Xie L, Yan Z, Wang Q, Li Y, Zhang L, Han Y, Li H, Du Y, Yang Y,
Guo X. High TXLNA expression predicts favourable outcome for pancre-
atic adenocarcinoma patients. Biomed Res Int. 2020;25(2020):2585862. https://doi.org/10.1155/2020/2585862. PMID:32185195;PMCID:
PMC7060861. Hu et al. Chinese Neurosurgical Journal (2023) 9:27 Page 10 of 10 Page 10 of 10 Hu et al. Chinese Neurosurgical Journal (2023) 9:27 25. Zhao J, Wang L, Kong D, Hu G, Wei B. Construction of novel DNA
methylation-based prognostic model to predict survival in glioblastoma. J Comput Biol. 2020;27(5):718–28. https://doi.org/10.1089/cmb.2019.
0125. (Epub 2019 Aug 28 PMID: 31460783). 9. Oba-Shinjo SM, Bengtson MH, Winnischofer SM, Colin C, Vedoy CG, de
Mendonça Z, Marie SK, Sogayar MC. Identification of novel differentially
expressed genes in human astrocytomas by cDNA representational
difference analysis. Brain Res Mol Brain Res. 2005;140(1–2):25–33. https://
doi.org/10.1016/j.molbrainres.2005.06.015. (Epub 2005 Aug 8 PMID:
16084624). 10. Ambrus JL Jr, Pippin J, Joseph A, Xu C, Blumenthal D, Tamayo A,
Claypool K, McCourt D, Srikiatchatochorn A, Ford RJ. Identification of
a cDNA for a human high-molecular-weight B-cell growth factor. Proc
Natl Acad Sci U S A. 1993;90(13):6330–4. https://doi.org/10.1073/pnas.
90.13.6330. Erratum.In:ProcNatlAcadSciUSA.1996Jul23;93(15):8154. PMID:8327514;PMCID:PMC46922. 11. Mashidori T, Shirataki H, Kamai T, Nakamura F, Yoshida K. Increased alpha-
taxilin protein expression is associated with the metastatic and invasive
potential of renal cell cancer. Biomed Res. 2011;32(2):103–10. https://doi.
org/10.2220/biomedres.32.103. (PMID: 21551945). 12. Ford R, Tamayo A, Martin B, Niu K, Claypool K, Cabanillas F, Ambrus J Jr. Identification of B-cell growth factors (interleukin-14; high molecular
weight-B-cell growth factors) in effusion fluids from patients with aggres-
sive B-cell lymphomas. Blood. 1995;86(1):283–93 (PMID: 7795235). 13. Wang Y, Sakaguchi M, Sabit H, Tamai S, Ichinose T, Tanaka S, Kinoshita M,
Uchida Y, Ohtsuki S, Nakada M. COL1A2 inhibition suppresses glioblas-
toma cell proliferation and invasion. J Neurosurg. 2022;138(3):639–48. https://doi.org/10.3171/2022.6.JNS22319. (PMID: 35932265). 14. Lin P, Huang Z. Correlation analysis connects cancer subtypes. PLoS One. 2013;8(7):e69747 PMID: 23861980; PMCID: PMC3704535. 15. 26. Liu Q, Dai M, Guo J, Wu H, Wang W, Chen G, Hu Y, Han X, Xu Q, Zhang X,
Yang S, Zhang Y, Kleeff J, Liao Q, Wu W, Liang Z, Zhang T, Zhao Y. Long-
term survival, quality of life, and molecular features of the patients with
solid pseudopapillary neoplasm of the pancreas: a retrospective study
of 454 cases. Ann Surg. 2023. https://doi.org/10.1097/SLA.0000000000
005842. Epub ahead of print. PMID: 37036095. 25. Zhao J, Wang L, Kong D, Hu G, Wei B. Construction of novel DNA
methylation-based prognostic model to predict survival in glioblastoma.
J Comput Biol. 2020;27(5):718–28. https://doi.org/10.1089/cmb.2019.
0125. (Epub 2019 Aug 28 PMID: 31460783). Conclusion
TXLNA Chen F, Cui JJ, Jiang DC, Wang HZ, Zhuang W, Feng YN, Lin XL, Xi SY. Anti-
tumor mechanism of kangliu pill on gliomas in mice through PI3K-Akt
signaling pathway. J Ethnopharmacol. 2023;307:116252 Epub 2023 Feb
11. PMID: 36775078. 16. Zhong D, Ran JH, Tang WY, Zhang XD, Tan Y, Chen GJ, Li XS, Yan Y. Mda-9/
syntenin promotes human brain glioma migration through focal adhe-
sion kinase (FAK)-JNK and FAK-AKT signaling. Asian Pac J Cancer Prev. 2012;13(6):2897–901. https://doi.org/10.7314/apjcp.2012.13.6.2897. (PMID: 22938480). 17. Mayoral-Varo V, Jiménez L, Link W. The critical role of TRIB2 in cancer and
therapy resistance. Cancers (Basel). 2021;13(11):2701. https://doi.org/10.
3390/cancers13112701. PMID:34070799;PMCID:PMC8198994. 18. Yau EH, Kummetha IR, Lichinchi G, Tang R, Zhang Y, Rana TM. Genome-
wide CRISPR screen for essential cell growth mediators in mutant KRAS
colorectal cancers. Cancer Res. 2017;77(22):6330–9. https://doi.org/10.
1158/0008-5472.CAN-17-2043. Epub 2017 Sep 27. PMID: 28954733;
PMCID: PMC5690866. 19. Wang S, Tailor K, Kwabi-Addo B. Androgen-induced epigenetic profiles
of polycomb and trithorax genes in prostate cancer cells. Anticancer Res. 2020;40(5):2559–65. https://doi.org/10.21873/anticanres.14226. PMID:323
66400;PMCID:PMC8833844. 20. Klepinin A, Miller S, Reile I, Puurand M, Rebane-Klemm E, Klepinina L, Vija
H, Zhang S, Terzic A, Dzeja P, Kaambre T. Stable isotope tracing uncovers
reduced γ/β-ATP turnover and metabolic flux through mitochondrial-
linked phosphotransfer circuits in aggressive breast cancer cells. Front
Oncol. 2022;12:892195 PMID: 35712500; PMCID: PMC9194814. 21. Chen D, Zhou H, Cai Z, Cai K, Liu J, Wang W, Miao H, Li H, Li R, Li X, Chen Y,
Wang HY, Wen Z. CircSCAP interacts with SF3A3 to inhibit the malignance
of non-small cell lung cancer by activating p53 signaling. J Exp Clin
Cancer Res. 2022;41(1):120. https://doi.org/10.1186/s13046-022-02299-0.
PMID:35365208;PMCID:PMC8973551. •
fast, convenient online submission
•
thorough peer review by experienced researchers in your field
•
rapid publication on acceptance
•
support for research data, including large and complex data types
•
gold Open Access which fosters wider collaboration and increased citations
maximum visibility for your research: over 100M website views per year
•
At BMC, research is always in progress. Learn more biomedcentral.com/submissions
Ready to submit your research
Ready to submit your research ? Choose BMC and benefit from:
? •
fast, convenient online submission
•
thorough peer review by experienced researchers in your field
•
rapid publication on acceptance
•
support for research data, including large and complex data types
•
gold Open Access which fosters wider collaboration and increased citations
maximum visibility for your research: over 100M website views per year
•
At BMC, research is always in progress.
Learn more biomedcentral.com/submissions
Ready to submit your research
Ready to submit your research ? Choose BMC and benefit from:
? Choose BMC and benefit from: 25. Zhao J, Wang L, Kong D, Hu G, Wei B. Construction of novel DNA
methylation-based prognostic model to predict survival in glioblastoma.
J Comput Biol. 2020;27(5):718–28. https://doi.org/10.1089/cmb.2019.
0125. (Epub 2019 Aug 28 PMID: 31460783).
26. Liu Q, Dai M, Guo J, Wu H, Wang W, Chen G, Hu Y, Han X, Xu Q, Zhang X,
Yang S, Zhang Y, Kleeff J, Liao Q, Wu W, Liang Z, Zhang T, Zhao Y. Long-
term survival, quality of life, and molecular features of the patients with
solid pseudopapillary neoplasm of the pancreas: a retrospective study
of 454 cases. Ann Surg. 2023. https://doi.org/10.1097/SLA.0000000000
005842. Epub ahead of print. PMID: 37036095. Conclusion
TXLNA Choose BMC and benefit from: •
fast, convenient online submission
•
thorough peer review by experienced researchers in your field
•
rapid publication on acceptance
•
support for research data, including large and complex data types
•
gold Open Access which fosters wider collaboration and increased citations
maximum visibility for your research: over 100M website views per year
•
At BMC, research is always in progress. Learn more biomedcentral.com/submissions
Ready to submit your research
Ready to submit your research ? Choose BMC and benefit from:
? Choose BMC and benefit from: 22. Yang J, Hou Z, Wang C, Wang H, Zhang H. Gene expression profiles reveal
key genes for early diagnosis and treatment of adamantinomatous crani-
opharyngioma. Cancer Gene Ther. 2018;25(9–10):227–39. https://doi.org/
10.1038/s41417-018-0015-4. (Epub 2018 Apr 23 PMID: 29681617). 23. Katsarou SD, Messaritakis I, Voumvouraki A, Kakavogiannis S, Kotsakis A,
Alkahtani S, Stournaras C, Martin SS, Georgoulias V, Kallergi G. Detyrosi-
nated α-tubulin, vimentin and PD-L1 in circulating tumor cells (CTCs)
isolated from non-small cell lung cancer (NSCLC) patients. J Pers Med. 2022;12(2):154. https://doi.org/10.3390/jpm12020154. PMID:35207643;P
MCID:PMC8875112. 24. Nie X, Yang S, Mu G, Wang M, Ye Z, Zhou M, Dai W, Chen W. AMER3 variants
modify the U-shaped association of urinary total hydroxyphenanthrene
with fasting plasma glucose: A newfound gene-environment interaction. Environ Pollut. 2022;310:119898 Epub 2022 Aug 5. PMID: 35940488.
|
https://openalex.org/W2570523276
|
http://turczaninowia.asu.ru/article/download/1511/1114
|
Russian
| null |
New findings in the flora of the south-eastern shore of the lake Baikal (region of Khamar-Daban mountain range): the nemoral relicts of tertiary flora and rare species
|
Turczaninowia
| 2,016
|
cc-by
| 8,858
|
Находки во флоре юго-восточного (Хамар-Дабанского) побережья
оз. Байкал: реликты третичной неморальной флоры и редкие виды М. М. Иванова, С. Г. Казановский, А. А. Киселева Сибирский институт физиологии и биохимии растений СО РАН, ул. Лермонтова, 132, г. Иркутск, 664033, Россия
E-mail: skazanovsky@mail.ru Ключевые слова: неморальные реликты, редкие виды, Иркутская область, Республика Бурятия, юго-восточ
ное побережье оз. Байкал. Аннотация. В сообщении приводятся сведения о находках 23 редких и 11 реликтовых видов растений
на юго-восточном побережье оз. Байкал, из которых Epilobium davuricum впервые для Бурятии, и 5 видов –
впервые для юго-восточного побережья Байкала (Spiranthes sinensis, Cotoneaster uniflorus, Potentilla flagellaris,
Utricularia intermedia, Pilosella dublitzkii). Turczaninowia 19 (3): 94–105 (2016)
DOI: 10.14258/turczaninowia.19.3.6
http://turczaninowia.asu.ru Turczaninowia 19 (3): 94–105 (2016)
DOI: 10.14258/turczaninowia.19.3.6
http://turczaninowia.asu.ru Turczaninowia 19 (3): 94–105 (2016)
DOI: 10.14258/turczaninowia.19.3.6
http://turczaninowia.asu.ru ISSN 1560–7259 (print edition)
TURCZANINOWIA
ISSN 1560–7267 (online edition) УДК 581.95(571.53+571.54) New findings in the flora of the south-eastern shore of the lake Baikal
(region of Khamar-Daban mountain range): the nemoral relicts
of tertiary flora and rare species M. M. Ivanova, S. G. Kazanovsky, A. A. Kiseleva Siberian Institute of Plant Physiology and Biochemistry, Siberian Branch of the Russian Academy of Sciences,
Lermontov Str., 132, Irkutsk, 664033, Russia Поступило в редакцию 25.05.2016
Принято к публикации 29.05.2016 ey words: nemoral relicts, rare species, Irkutsk region, Republic of Buryatia, south-eastern shore of the lak Аносовка, низовье, смешанный лес (бе
реза, ель, пихта, кедр, тополь), 22 VIII 2001, СК,
ID 16756; у слияния рек Аносовка и Правая Ано
совка, кедрово-еловый лес у реки, 21 VIII 2001,
СК, ID 16755. Имена и фамилии основных коллекторов со
кращены: МИ – М. М. Иванова, СК – С. Г. Каза
новский, АК – А. А. Киселева. Кроме общепринятых, использованы следую
щие сокращения: ост. п. – остановочный пункт,
ж. д. – железная дорога, железнодорожный (-ая),
окр. – окрестности, БЦБК – Байкальский целлю
лозно-бумажный комбинат. Большинство процитированных гербарных
образцов хранятся в Гербарии Сибирского ин
ститута физиологии и биохимии растений (СИ
ФИБР) СО РАН, г. Иркутск (IRK); дублеты пере
даны в Гербарий Южно-Сибирского ботаниче
ского сада Алтайского государственного универ
ситета, г. Барнаул (ALTB), а также дублеты ряда
видов переданы в другие гербарии: Иркутского
государственного университета (IRKU), Цен
трального Сибирского ботанического сада СО
РАН, г. Новосибирск (NS), там же, Гербарий им. М. Г. Попова (NSK). Номера гербарных образцов
(ID), хранящихся в IRK, приводятся без указания
акронима гербария. Polystichum lonchitis (L.) Roth (Dryopterida
ceae) – циркумполярный вид с дизъюнктивным
ареалом. В Центральной Сибири имеется не
сколько изолированных участков ареала, один
из них – на Хамар-Дабане – от р. Слюдянка на
западе до р. Мишиха на востоке: реки Слюдянка,
Безымянная, Утулик, Хара-Мурин, Муринский
голец, окр. с. Выдрино, Снежнинские озера, р. Большой Мамай, р. Осиновка близ ст. Танхой,
р. Переёмная, р. Мишиха. Встречается в субаль
пийском и в верхней части горно-лесного пояса
(Turczaninow, 1856; Epova, 1956; Kiseleva, 1978;
Vasilchenko et al., 1978; Red Book.., 2001, 2010). Большинство авторов считает данный вид не
моральным реликтом. Однако, И. И. Гуреева
(Gureyeva, 2001) относит его к числу реликто
вых элементов плиоценовых высокогорий. Протяженность обследованной территории
составляет около 225 км. Местонахождения
видов цитируются с запада на восток. Граница
между Иркутской областью и Республикой Буря
тией проходит по р. Снежной. Станция Выдрино
находится в правобережье р. Снежной и отно
сится к Республике Бурятия. р
Приводим новые местонахождения из этого
района. Иркутская обл.: район горы Травянистая
(бассейн р. Бабха), темнохвойный лес, без даты,
аноним, ID 177; бассейн р. Лангатуй, крутой вос
точный склон к ручью – притоку р. Голая, пих
товый разнотравный лес, 23 VIII 1998, СК, МИ,
ID 16780, 16781; окр. г. Байкальск, первый левый
приток р. Большая Осиновка, папоротниково-
разнотравный разреженный пихтовый лес, 09
VIII 1999, А. С. Плешанов, ID 16778; 6 км юж
нее ост. п. Солзан, среднее течение р. ey words: nemoral relicts, rare species, Irkutsk region, Republic of Buryatia, south-eastern shore of the lak Summary. New data on distribution of 23 rare and 11 relic species of plants are presented in the article. One spe
cies (Epilobium davuricum) is new for Buryatia Republic, 5 are newly found on the south-eastern shore of the lake
Baikal (Spiranthes sinensis, Cotoneaster uniflorus, Potentilla flagellaris, Utricularia intermedia, Pilosella dublitzkii). Д. Крапивкина (Polozhij, Krapivkina, 1985). О не
моральных реликтах в бриофлоре писали Л. В. Бардунов (Bardunov, 1963) и С. Г. Казановский
(Kazanovsky, 2003). Наше сообщение касается находок некоторых
неморальных реликтов и редко встречающихся
видов на северном макросклоне хребта Хамар-
Дабан и на предгорных равнинах юго-восточно
го побережья Байкала. Данная территория явля
ется наиболее богатой реликтами третичной не
моральной флоры в Центральной Сибири. О ре
ликтах этого района писали М. Г. Попов (Popov,
1955), Н. А. Епова (Epova, 1956), А. А. Киселева
(Kiseleva, 1978), Л. И. Малышев и Г. А. Пешкова
(Malyshev, Peshkova, 1979), А. В. Положий и Э. Кроме собственных сборов авторы исполь
зовали гербарные образцы других коллекторов,
хранящиеся в Гербариях Иркутска (IRK, IRKU),
Новосибирска (NSK). Базу данных по этим гер
бариям для юго-восточного побережья Байкала
подготовил С. Г. Казановский. Нами были учте
ны сборы 1970-х гг. одного из авторов настоящей Поступило в редакцию 25.05.2016
Принято к публикации 29.05.2016 Submitted 25.05.2016
Accepted 29.05.2016 Turczaninowia 19 (3): 94–105 (2016) 95 статьи – А. А. Киселевой, которые ранее не пу
бликовались и, в основном, хранятся в NSK, от
части в IRK. Выдриная, Переёмная (Epova, 1956; Kiseleva,
1978; Kiseleva et al., 1990; Red Book.., 2001, 2010;
Abramova, Volkova, 2011). Приводится Н. С. Тур
чаниновым без указания местонахождений (Tur
czaninow, 1856). Новые находки относятся к из
вестному участку ареала на хр. Хамар-Дабан. Названия растений даются в соответствии со
сводкой «Конспект флоры Иркутской области»
(Check-list of the vascular..., 2008). Виды расте
ний каждого раздела цитируются в порядке рас
положения семейств по системе Энглера, внутри
семейств – по алфавиту латинских названий рас
тений. Принадлежность видов к хорологическим
группам дается в основном по Л. И. Малышеву и
Г. А. Пешковой (Malyshev, Peshkova, 1984). Иркутская обл.: р. Большая Осиновка близ г. Байкальск, в долинном лесу, 19 VIII 2006, МИ,
ID 34068, 35844 (ALTB); левобережье р. Снеж
ная, долинный лес в окр. Теплых (Карьерских)
озер, 13 VIII 2006, МИ, ID 34069; р. Тальцы –
левый приток р. Снежная, субальпийский разно
травный луг, 01 VIII 1994, СК, ID 16749. Буря
тия: р. Большой Мамай, верхнее течение, левый
берег, кедрово-пихтовый лес, 13 IX 2007, СК, ID
2474; р. ey words: nemoral relicts, rare species, Irkutsk region, Republic of Buryatia, south-eastern shore of the lak Большая
Осиновка, правый борт, елово-пихтовый лес, 11
VII 2000, С. И. Шаманова, Т. А. Осколкова, ID
16779; в 5 км южнее ост. п. Солзан, левый берег
р. Малая Осиновка, пихтовый черничный зеле Третичные реликты Большая часть приведенных видов относятся
к неморальным реликтам. Dryopteris filix-mas (L.) Schott (Dryopterida
ceae) – вид с почти космополитным, но дизъ
юнктивным распространением. В Центральной
Сибири имеются изолированные участки ареа
ла, наиболее крупный из них – на юго-восточ
ном побережье оз. Байкал между ст. Утулик и
р. Переёмная: реки Утулик, Солзан, Снежная, 96 Иванова М. М. и др. Находки во флоре юго-восточного побережья Байкала лесу, МИ, 12 VIII 2013, ID 34062; р. Выдриная,
долинный смешанный лес с папоротником стра
усником обыкновенным, МИ, 11 VIII 2008, ID
34063, 35843 (ALTB). номошный лес, Г. В. Матяшенко, 01 IX 1973, ID
31700; р. Снежная, среднее течение, тополевый
разнотравный лес, 01 VIII 1994, СК, ID 16777; р. Тальцы – левый приток р. Снежной, высокотра
вье у верхней границы леса, 15 VIII 2006, МИ,
ID 34065, 34066 (ALTB); там же, верхняя часть
горно-лесного пояса, каменистые замшелые
склоны к ручью, 20 V 1995, МИ, ID 34064; там
же, субальпийский пояс, долина ручья, под сы
рыми скалами, 23 VI 2006, Н. В. Степанцова, ID
11301; окр. горы Пик Тальцинский, верхняя гра
ница леса, пихтовое редколесье, каменная рос
сыпь, 22 VIII 2002, СК, ID 16776. Бурятия: в 3 км
выше слияния рек Аносовка и Правая Аносовка,
замшелая крупноглыбовая россыпь вдоль водо
тока, 22 VI 1995, СК, ID 16783; Байкальский за
поведник, Осиновский голец, верхняя часть лес
ного пояса, пихтовый лес, каменистая россыпь,
04 VII 1990, СК, ID 16784. Brachypodium sylvaticum (Huds.) P. Beauv. (Poaceae) – распространен в Европе и на юге
Азиатского материка от Малой Азии до Японии
(Tzvelev, 1974). Отмечен в долине р. Снежная
(Epova , 1956; Flora of the Central..., 1979) и на
пике Тальцинском (Red Book.., 2010). Мы сомне
ваемся в недавно указанном нахождении данно
го вида в низовьях р. Мишиха (Krasnopevtseva
et al., 2006; Abramova, Volkova, 2011), поскольку
гербарный материал не был собран. Приводим новые местонахождения. Иркут
ская обл.: бассейн р. Снежная, левобережье, окр. горы Пик Тальцинский, верхняя граница леса,
пихтовое редколесье, берег ручья, 22 VIII 2001,
СК, ID 6867–6869, 6866 (ALTB). Бурятия, доли
на р. Большой Мамай, в горнолесном поясе, ко
нец августа 1981, МИ, ID 34072. Oreopteris limbosperma (All.) Holub (Thely-
pteridaceae). Циркумполярный горный вид с пре
рывистым распространением. На Хамар-Дабане
представлен изолированный участок ареала от
ст. Мурино до р. Левая Мишиха: р. Хара-Мурин,
Муринский голец, голец Мангылы, по левому
берегу р. Снежной, близ ст. Выдрино, р. Боль
шой Мамай, ст. Танхой, верховья р. Левая Ми
шиха, р. Третичные реликты Байкальск, западная
окраина, левобережье р. Харлахта, парк (сохра
нившийся березовый лес), 27 VI 2006, МИ, ID
35709; ст. Мурино, на лугу, 27 VII 1974, АК, №
293 (NSK). Был отмечен нами также у полотна ж. д. к востоку от ст. Мурино (М.М. Иванова, лич
ное сообщение). Бурятия, окр. ст. Выдрино, 186-
й км тракта Иркутск – Чита, подножье насыпи
ниже тракта, 04 VII 2014, МИ, ID 36415, 36448,
36449 (ALTB), здесь, по-видимому, заносный. Приводим новые местонахождения: Иркут
ская область, близ ост. п. Садовый, на просеке
ЛЭП, 02 IX 2008, МИ, ID 34085, 35872 (ALTB);
там же, 20 VI 2000, МИ, ID 34086; левобережье
р. Снежная, окр. турбазы «Теплые озера», при
брежные заросли ивы и тополя, 13 VII 2014, СК,
МИ, ID 36242, 36243, 36244 (ALTB). Бурятия,
правобережье р. Снежная, близ лесной дороги
на Соболиные озера, между 1-й и 2-й просека
ми ЛЭП, кедрово-березовый лес с травяным по
кровом и папоротниками, 06 VII 2014, МИ, ID
36403, 36444 (ALTB). Veronica officinalis L. (Scrophulariaceae) – пре
имущественно европейский вид. В Центральной
Сибири отмечен на юго-восточном побережье оз. Байкал (Flora of Cenral..., 1979; Polozhij, 1996),
где приводится для г. Бабушкин, ст. Мысовая,
низовьев рек Снежная и Хара-Мурин, р. Осинов
ка (Мысовская), р. Тельная, ст. Танхой (Epova,
1956; Popov, 1959; Kiseleva, 1978; Zarubin et al.,
1989; Red Book.., 2001, 2010). Растение встрече
но нами также в удалении от Байкала: Иркутская
обл., Шелеховский р-н, ст. Большая Глубокая,
между 73-м и 74-м км Култукского тракта (рас
стояние от Иркутска), на проселочной дороге,
заросшей травой, 2 VIII 1998, МИ (IRKU). Ря
дом авторов считается третичным неморальным
реликтом (Epova, 1956; Kiseleva, 1978; Stepanov,
1997). Мы присоединяемся к этому мнению, но
не можем не отметить, что этот вид кроме есте
ственных местообитаний довольно активно рас
пространяется вдоль дорог и троп. Waldsteinia ternata (Stephan) Fritsch (Rosa-
ceae) – южносибирский эндемичный вид, оби
тает на юго-восточном побережье Байкала, изо
лированные местонахождения известны в пред
горьях Восточного Саяна (реки Онот и Зима), в
Западном Саяне (Красноярский край, Хакасия). Близкие виды: W. tansybeica Stepanov описан из
Западного Саяна (Red Book..., 2005), и W. maxi
movicziana (Teppner) Probat. распространен в
Южном Приморье, на о. Сахалин, в Японии
и Китае (Flora of Russian.., 2006; Red Book …,
2010, 2013). Указываем самое восточное местонахожде
ние на Байкале: Бурятия, устье р. Мишиха, лес,
14 VI 1987, АК, ID 13926, 13927. Aegopodium latifolium Turcz. (Apiaceae) – эн
дем юго-восточного побережья оз. Байкал. Третичные реликты Последнее
указание на произрастание здесь этого вида в
естественных условиях требует подтверждения,
гербарных образцов мы не видели и наши специ
альные поиски не дали положительных резуль
татов. Лангатуй (Kiseleva, 1978; Ivanova, 2003). Для
смежной территории Бурятии приводился для
окр. ст. Выдрино (Malyshev, Peshkova, 1979; Red
Book …, 2010; Red Book ..., 2013). Последнее
указание на произрастание здесь этого вида в
естественных условиях требует подтверждения,
гербарных образцов мы не видели и наши специ
альные поиски не дали положительных резуль
татов. Лангатуй (Kiseleva, 1978; Ivanova, 2003). Для
смежной территории Бурятии приводился для
окр. ст. Выдрино (Malyshev, Peshkova, 1979; Red
Book …, 2010; Red Book ..., 2013). Последнее
указание на произрастание здесь этого вида в
естественных условиях требует подтверждения,
гербарных образцов мы не видели и наши специ
альные поиски не дали положительных резуль
татов. триха) и на юго-восточном побережье оз. Байкал
(ст. Боярск, р. Мишиха, р. Выдриная, р. Ланга
туй, р. Бабха) (Kiseleva, 1978; Olonova, 1990; Za
rubin et al., 1993; Ivanova, 1999). триха) и на юго-восточном побережье оз. Байкал
(ст. Боярск, р. Мишиха, р. Выдриная, р. Ланга
туй, р. Бабха) (Kiseleva, 1978; Olonova, 1990; Za
rubin et al., 1993; Ivanova, 1999). Новая находка лежит между реками Ланга
туй и Бабха: окр. г. Байкальска, правобережье р. Большая Осиновка, во мху по берегу протоки, 19
VIII 2006, МИ, ID 34083, 35846 (ALTB). Carex hancockiana Maxim. (Cyperaceae) –
восточноазиатский вид. В Сибири встречается
фрагментарно. На юго-восточном побережье
Байкала отмечен изредка в горно-лесном поясе
хр. Хамар-Дабан в следующих пунктах: п. Кул
тук (Popov, 1957), р. Слюдянка, близ ост. п. Су
хой Ручей, р. Утулик и его приток р. Шубутуй,
близ ст. Мурино, р. Мангылы (Kiseleva, 1978;
Red Book.., 2001, 2010). Carex hancockiana Maxim. (Cyperaceae) –
восточноазиатский вид. В Сибири встречается
фрагментарно. На юго-восточном побережье
Байкала отмечен изредка в горно-лесном поясе
хр. Хамар-Дабан в следующих пунктах: п. Кул
тук (Popov, 1957), р. Слюдянка, близ ост. п. Су
хой Ручей, р. Утулик и его приток р. Шубутуй,
близ ст. Мурино, р. Мангылы (Kiseleva, 1978;
Red Book.., 2001, 2010). Приводим новые находки. Иркутская обл.: р. Безымянная, в нижнем течении, в смешанном
лесу, 08 VIII 1974, АК, № 2189 (NSK); там же,
смешанный лес (береза, кедр, пихта), 22 VI 2001,
СК, ID 36412, 36413; окр. г. Байкальска, р. Боль
шая Осиновка, левый берег, пихтовый лес с ане
моной байкальской, 06 VIII 1999, СК, ID 36414;
там же, в долинном лесу, 17 VIII 2006, МИ, ID
35710, 35849 (ALTB); г. Третичные реликты Куркавка (Epova, 1956; Kiseleva, 1978;
Malyshev, Peshkova, 1979; Red Book.., 2001,
2010). Образует папоротниковые высокотравья в
субальпийском поясе. И. И. Гуреева (Gureyeva,
2001) считает его дериватом третичной лесной
флоры, вошедшей в состав субальпийского по
яса по мере подъема горных хребтов. Festuca altissima All. (Poaceae) – встречается
в Европе, на Кавказе, в Малой и Средней Азии
(низовья Каратала), известны изолированные ре
ликтовые местонахождения в Западной Сибири
(Салаир, Алтай, Кузнецкий Алатау), в Восточ
ном Саяне и на Хамар-Дабане (Tzvelev, 1974;
Malyshev, Peshkova, 1979; Alekseyev, 1990). На
Хамар-Дабане отмечен в долинах рек Снежная и
Мишиха (Epova, 1956; Kiseleva et al., 1990; Iva
nova 2003), в нижнем и среднем течении р. Вы
дриная (Abramova, Volkova, 2011). Приводим еще одну точку из бассейна р. Снежная: левобережье р. Тальцы – левого при
тока р. Снежная, кедрово-пихтовый папорот
никовый лес на склоне, 15 VIII 2006, МИ, ID
34073, 34079 (ALTB). Поблизости от Изумруд
ного озера (Карьерские озера), где это растение
было обнаружено нами ранее (Ivanova, 2003),
оказалась небольшая популяция у тропы, веду
щей к озеру Сказка, 15 VIII 2006, МИ, ID 34075,
34078 (ALTB). Другая находка относится к до
лине р. Выдриная – долинный смешанный лес с
травяным покровом, 10 VIII 2008, МИ, ID 34074,
35845 (ALTB). Приводим новые местонахождения. Иркут
ская обл.: левобережье р. Лангатуй выше устья
р. Голой, склон к реке, кедрово-пихтовый разно
травный лес, 22 VIII 1998, МИ, ID 16787–16789;
р. Большая Осиновка близ г. Байкальск, в тем
нохвойном лесу в верхней части горно-лесного
пояса, 17 VIII 2006, МИ, ID 34061 (данная наход
ка отодвигает к западу границу распространения
вида на Хамар-Дабане); левый борт долины р. Тальцы – левого притока р. Снежной, в пихто
вом парке, 15 VIII 2006, МИ, ID 34060; левобе
режье р. Снежная, окр. горы Пик Тальцинский,
каменная россыпь, СК, 10 VIII 1999, ID 1949;
там же, верхняя граница леса, пихтовое редколе
сье, 22 VIII 2002, СК, ID 7346, 7397, 7347 (NS);
там же, субальпийский луг, 10 VII 1999, СК, ID
16785, 16786. Бурятия: правобережье р. Снеж
ной, по дороге на Соболиные озера, в пихтовом Poa remota Forsell. (Poaceae) – обитает в
умеренной полосе Европы и Западной Сибири. Встречается в Средней Азии и Западном Китае. В Центральной Сибири встречается изолирован
но в Тайшетском р-не Иркутской области (с. Па Turczaninowia 19 (3): 94–105 (2016) 97 Лангатуй (Kiseleva, 1978; Ivanova, 2003). Для
смежной территории Бурятии приводился для
окр. ст. Выдрино (Malyshev, Peshkova, 1979; Red
Book …, 2010; Red Book ..., 2013). Редкие виды В этом разделе приводятся данные о редких
видах растений на юго-восточном побережье
Байкала, о новых находках, а также о редко со
биравшихся здесь растениях. Lycopodium juniperoideum Sw. (Lycopodia
ceae) – обитает в Восточной Азии и в Северной
Америке. В Центральной Сибири находится
у западной границы распространения. Приво
дится для правобережья р. Снежная (Malyshev,
Peshkova, 1979), ст. Танхой, р. Мишиха и р. Вы
дриная (Vasilchenko et al., 1978), р. Переёмная
(Abramova, Volkova, 2011). Указываем другие местонахождения с этого
побережья. Иркутская область, к востоку от ст. Мурино (5369-й км ж. д.), лес с кедром и бере
зой на возвышенности среди сфагнового болота,
25 IX 2006, МИ, ID 34070. Бурятия: низовье р. Большой Мамай, березово-еловый разнотравно-
зеленомошный лес, 19 VIII 2006, СК, ID 2325;
там же, березово-елово-кедровый чернично-раз
нотравный зеленомошный лес с пихтовым стла
ником, 15 VI 2011, Е. С. Преловская, ID 21352,
21423; ост. п. Мамай в смешанном лесу на низ
кой байкальской террасе (в сторону Байкала от
полотна ж. д.), 25 VI 2006, МИ, ID 34071, 35842
(ALTB). Естественными местообитаниями для вида
мы считаем следующие: Иркутская обл., низовье
р. Хара-Мурин, правый берег, кедрово-пихтовый
лес, 27 VIII 2003, СК, ID 43352; там же, смешан
ный зеленомошный лес с кедром, пихтой, елью,
березой, 27 VIII 2001, СК, ID 43353. Бурятия,
окр. ст. Выдрино, приустьевая часть р. Снежная,
кедрово-березовый лес с пихтой и елью, 13 VII
1992, МИ, ID 43351; окр. г. Бабушкин, правый
борт долины р. Мысовка, сосняк ольховнико
вый, 26 VIII 2002, Н. С. Бережная, ID 36421. Carex pallescens L. (Cyperaceae) – имеет голар
ктический ареал с обширными дизъюнкциями. Сборы в Прибайкалье и на Байкале немногочис
ленны: д. Патриха и д. Талая в Тайшетском р-не,
д. Тальники в Черемховском р-не, р. Осиновка
близ п. Танхой на Байкале (Malyshev, 1990); р. Большой Мамай (Ivanova, 2003), р. Мишиха, р. Переёмная (Abramova, Volkova, 2011). Galium paradoxum Ledeb. (Rubiaceae) – восточ
ноазиатский вид. Встречается редко. Отмечен в
долинах рек Безымянная, Утулик, Бабха, Солзан,
Малая Осиновка, Лангатуй, Снежная, Аносов
ка, Переёмная, ст. Мурино (Kiseleva, 1978; Red
Book ..., 2001, 2010). Приводим другие местонахождения с юго-
восточного побережья Байкала: Иркутская об
ласть, р. Хара-Мурин, нижнее течение, злако
во-разнотравный луг, 28 VII 2009, СК, ID 13335,
13336; левобережье р. Снежная, Карьерские
озера, опушка пихтово-кедрового леса, 13 VII
2014, СК, ID 36272, 36273 (ALTB); р. Тальцы –
левый приток р. Снежная, субальпийский луг,
23 VI 2001, СК, ID 10010, 21073; Бурятия, окр. ст. Третичные реликты Пун
кты сборов относятся к Слюдянскому району
Иркутской области (с запада на восток): падь
Улунтуй близ г. Слюдянка, реки Утулик, Бабха,
Харлахта, Солзан, Хара-Мурин и его приток Приводим новые находки, где растение встре
чается во вторичных местонахождениях. Иркут
ская обл.: ост. п. Солзан, близ очистных водое
мов БЦБК, на обочине дороги, 17 VIII 2006, МИ,
ID 35712, 35850 (ALTB); там же, в смешанном 98 Иванова М. М. и др. Иванова М. М. и др. Иванова М. М. и др.
Находки во флоре юго-восточного побережья Байкала лесу, 31 VII 2014, СК, ID 36418–36420, 36562,
36563 (ALTB); р. Осиновка близ г. Байкальска,
вдоль дороги, 31 VIII 2008, МИ, ID 35714; р. Хара-Мурин в приустьевой части близ автомо
бильного моста, на песке у русла, 16 V 1989,
аноним (IRKU); к востоку от ст. Мурино, 5367-й
км, пикет 2, опушка хвойного леса на обочине
дороги под ж. д. насыпью, 07 VIII 2013, МИ, ID
35713; между р. Малые Мангылы и ст. Выдрино,
5381-й км, пикет 2, сырой откос к грунтовой до
роге, 09 VIII 2013, МИ, ID 35717; левобережье
р. Снежной, лесная дорога от оз. Сказка к трак
ту, 14 VIII 2006, МИ, ID 35715; левобережье р. Снежной близ ст. Выдрино, кедрово-березовый
лес, у тропы, 13 VII 1992 (IRKU). Бурятия: окр. ст. Выдрино, обочина автомобильной дороги, 15
VII 2014, МИ, ID 36290, 36291 (ALTB); низовья
р. Малый Мамай, дорога на покосы, 19 IX 2003,
МИ, ID 35716; водораздел рек Мишиха и Болва
ниха, на лесной дороге в темнохвойном лесу, 02
VIII 1988, АК, ID 36422; р. Мысовка (Мысовая),
правый берег, на лесной дороге, 20 VI 1985, АК,
ID 36423, 36424. Редкие виды Байкальск, опушка смешанного леса, раз
нотравный луг, 31 VII 2014, СК, ID 36557, 36558,
36559 (ALTB). Бурятия, по дороге от ст. Выдрино
к одноименному поселку, на опушке пихтового
леса, 08 VIII 2013, МИ, ID 35695, 35840 (ALTB). Приводим другие местонахождения: Бурятия,
окр. ст. Выдрино, у ЛЭП, лесное озеро с заболо
ченными берегами, в воде, 16 VII 2014, СК, О. А. Якушев, ID 36124–36127, 36128 (ALTB); там же,
те же, ID 36308; там же, 16 VII 2014, те же, ID
36316; окр. ст. Речка Выдриная (2 км восточнее),
озеро, в воде, 13 VIII 2006, В. А. Краснобаев, ID
2318. Spiranthes sinensis (Pers.) Ames [S. amoena
(Bieb.) Spreng.] (Orchidaceae) – встречается в Си
бири, на Дальнем Востоке, в Восточной и Юж
ной Азии, в Австралии, заходит на северо-вос
ток европейской части России. Конкретных ука
заний для юго-восточного побережья Байкала в
литературе нами не найдено. Nymphaea tetragona Georgi (Nymphaeaceae) –
имеет бореальный голарктический ареал. Для
юго-восточного побережья Байкала показан в
окр. ст. Мурино, в устье р. Снежная, в низовье р. Выдриная, близ п. Танхой, п. Посольск, д. Исток
(Red Book…, 2010, 2013). Иркутская обл.: ст. Слюдянка, на закустарен
ном осоковом болоте, 04 VIII 1974, АК, Н. В. Власова, № 1935 (NSK), ID 36404. Бурятия, окр. ст. Выдрино, просека ЛЭП, 15 VII 2014, МИ, СК,
ID 36376; там же, 28 VII 2014, МИ, Л. А. Козли
кина, ID 36447. Приводим другие местонахождения: Бурятия,
окр. ст. Выдрино, высокая байкальская терра
са, озерно-болотный ландшафт, в озерах, 04 VII
2014, МИ, ID 36408, 36409 (ALTB); там же, 16
VII 2014, СК, О. А. Якушев, ID, 36129, 36304,
36307. Приводим другие местонахождения: Бурятия,
окр. ст. Выдрино, высокая байкальская терра
са, озерно-болотный ландшафт, в озерах, 04 VII
2014, МИ, ID 36408, 36409 (ALTB); там же, 16
VII 2014, СК, О. А. Якушев, ID, 36129, 36304,
36307. Sagina procumbens L. (Caryophyllaceae) – име
ет циркумполярное распространение. На Байка
ле сборы немногочисленны. На юго-восточном
побережье Байкала вид отмечен для ст. Танхой и
Выдрино (Flora of Central ..., 1979), р. Выдриная
(Abramova, Volkova, 2011). Truellum sieboldii (Meissn.) Soják (Polygona
ceae) – восточноазиатский вид. В Прибайкалье
собирался редко (Zarubin et al., 1989; Tupitsyna,
1992; Ivanova, 2003), на юго-восточном побере
жье Байкала указывался для старицы р. Мишихи
близ устья (Abramova, Volkova, 2011). Приводим другие местонахождения: Иркут
ская область: ст. Утулик, на лугу, 08 VII 1974,
АК, № 837 (NSK), р. Солзан, левый берег, против
БЦБК, опушка кедрово-березового разнотравно
го леса, 14 VI 2014, Н. Редкие виды Выдрино, на просеке ЛЭП, 04 VII 2014, МИ,
ID 36402; низовья р. Толбазиха, березовый лес
с травяным покровом и папоротниками, 04 VII
2014, МИ, ID 36445; там же, кедрово-пихтово-
березовый чернично-разнотравный лес с елью,
15 VII 2014, СК, ID 36293, 36294 (ALTB); низо
вье р. Выдриная, на луговой поляне среди сме Нами обнаружен в правобережье р. Снежная
(Республика Бурятия): низовье, низкая речная
терраса, тополевый лес с пихтой и кедром с по
кровом из вальдштейнии тройчатой и анемоны
байкальской, 06 VII 2014, МИ, ID 36427; р. Се
ленгинка – правый приток р. Снежная, верхний
конец Большого Соболиного озера, в узком уще
лье, в темной сырой нише под каменной глыбой,
12 VIII 2013, МИ, ID 35718, 35851 (ALTB), рас
тет вместе с цирцеей альпийской и подмаренни
ком трехцветковым; ост. п. Мамай, 13 IX 1953,
А. В. Смирнов (IRKU). Turczaninowia 19 (3): 94–105 (2016) 99 шанного леса, 23 VI 2000, МИ, ID 10262, 17269,
17270; там же, злаково-разнотравный луг, 07 VII
2009, СК, ID 23023; левобережье р. Выдриная,
на сыром песке у русла, 11 VIII 2008, МИ, ID
35719; правобережье р. Снежная, берег Малого
Соболиного озера, 24 VII 2009, МИ, ID 35721. Выдрино, мелкощебнистый пологий склон ниже
тракта, 04 VII 2014, МИ, ID 36405; между ст. Вы
дрино и д. Толбазиха, мелкощебнистый склон у
тракта, 04 VII 2014, МИ, ID 36406; ст. Танхой, 24
VII 1952, И. И. Андреева, Л. В. Бардунов (NSK) –
2 листа; устье р. Мишихи, на галечнике, 03 X
2009, МИ, ID 35696; у д. Клюевка, 22 VII 1952,
И. И. Андреева, Л. В. Бардунов (NSK); р. Манту
риха в низовьях, на месте высыхающего озерка,
13 VIII 1975, АК, Н. В. Власова, № 1046 (NSK). Epipactis helleborine (L.) Crantz. (Orchidaceae) –
евразиатский вид. На юго-восточном побережье
Байкала показан для п. Култук и р. Большая Оси
новка (Check-list of the vascular.., 2008). Nuphar pumila (Timm) DC. (Nymphaeaceae) –
распространен в Евразии. На юго-восточном по
бережье встречается близ п. Култук, ст. Мурино,
по р. Снежной (Check-list of the vascular.., 2008);
имеются также указания для прибайкальских
террас на территории Байкальского заповедника
без конкретных пунктов (Krasnopevtseva et al.,
2006; Abramova, Volkova, 2011). Приводим новые местонахождения. Иркут
ская обл.: юго-восточная окраина ост. п. Солзан,
близ моста через р. Большая Осиновка, левый
берег, осиновый разнотравный лес, 28 VII 2011,
Д. А. Кривенко, Е. В. Жмудь, ID 23517, 23518;
окр. г. Иванова М. М. и др.
Находки во флоре юго-восточного побережья Байкала колея дороги ниже ж. д. насыпи, 09 VIII 2013,
МИ, ID 35779, 35868 (ALTB). Бурятия: окр. п. Выдрино, на илистом берегу ручья, 18 VIII 1973,
АК, Н. В. Власова, № 1957 (NSK); ост. п. Клюев
ка, 22 VII 1953, Л. В. Бардунов, И. И. Андреева
(NSK); р. Мысовая, в 9 км от устья, по ручью, 19
VII 1975, АК, Н. В. Власова, № 525 (NSK). Приводим новые местонахождения близ Бай
кала: Иркутская обл., хр. Хамар-Дабан, водо
раздел рек Слюдянка и Подкомарная, верхняя
часть лесного пояса, лавовое обнажение, щебни
стый участок, 10 VI 1997, МИ, ID 35703, 35848
(ALTB); там же 01 IX 2003, МИ, ID 35700, 35701;
35847, 35702 (ALTB); окр. г. Слюдянка, долина р. Слюдянка, правый берег, смешанный лес, 15 VI
2011, Н. В. Степанцова, ID 21607. Приводим новые местонахождения близ Бай
кала: Иркутская обл., хр. Хамар-Дабан, водо
раздел рек Слюдянка и Подкомарная, верхняя
часть лесного пояса, лавовое обнажение, щебни
стый участок, 10 VI 1997, МИ, ID 35703, 35848
(ALTB); там же 01 IX 2003, МИ, ID 35700, 35701;
35847, 35702 (ALTB); окр. г. Слюдянка, долина р. Слюдянка, правый берег, смешанный лес, 15 VI
2011, Н. В. Степанцова, ID 21607. Сoccyganthe flos-cuculi (L.) Fourr. [Coronaria
flos-cuculi (L.) A. Br.] (Caryophyllaceae) – евро-
сибирский вид. На юго-восточном побережье
Байкала указан для рек Мангылы и Снежной
(Zarubin et al., 1989; Check-list …, 2008), в Буря
тии на территории Байкальского заповедника по
р. Мишиха (Vasilchenko et al., 1978). Potentilla flagellaris Willd. ex Schlecht. (Rosa
ceae) – североазиатский вид. Для юго-восточно
го побережья Байкала не приводится (Check-list
of the vascular …, 2008; Vasilchenko et al., 1978). Указываем местонахождение этой лапчатки:
Бурятия, ост. п. Мамай, опушка кедрово-пих
тового леса вдоль тропы к берегу Байкала, 26
VI 2008, МИ, ID 35756, 35757 (ALTB), 35866
(ALTB). Дополняем эти сведения. Иркутская область:
р. Паньковка в нижнем течении, на лугу, 16 VII
1974, АК № 406 (NSK); там же, на краю болота,
20 VI 1974, AK, № 184 (NSK); р. Малые Мангы
лы в нижнем течении, 14 VII 1974, AK, № 421
(NSK); между реками Большие и Малые Мангы
лы, 5377-й км, на протяжении 5-го и 6-го пике
тов, луга вдоль дороги ниже ж. д. Иванова М. М. и др.
Находки во флоре юго-восточного побережья Байкала насыпи, 14 VII
2012, МИ, ID 35776; там же, 09 VIII 2013, МИ, ID
35777, 35778 (ALTB), 35870 (VLA); между река
ми Малые Мангылы и Снежная, 5380-й км, пи
кет 7, 14 VII 2012, МИ, ID 35775, 35869 (ALTB);
в 3 км западнее р. Снежная, разнотравный луг,
у дороги, 24 VI 2001, СК, ID 10867, 17637; р. Мишиха, на лугу, 13 VII 1973, АК, Н. Коваленко
(NSK). Rosa amblyotis C. A. Mey. [R. jacutica Juz.]
(Rosaceae) – северо-восточноазиатский вид. На
юго-восточном побережье отмечался на р. Пере
ёмная (Abramova, Volkova, 2011). Rosa amblyotis C. A. Mey. [R. jacutica Juz.]
(Rosaceae) – северо-восточноазиатский вид. На
юго-восточном побережье отмечался на р. Пере
ёмная (Abramova, Volkova, 2011). Приводим собранные нами гербарные образ
цы: Иркутская обл., левобережье р. Снежная, ке
дрово-пихтовый разнотравно-вальдштейниевый
леc, 12 VII 2014, МИ, ID 36281, 36282 (ALTB). Бурятия, долина р. Выдриная, смешанный до
линный лес с травяным покровом, 11 VIII 2008,
МИ, ID 35771, 35772, 35773 (ALTB). Приводим собранные нами гербарные образ
цы: Иркутская обл., левобережье р. Снежная, ке
дрово-пихтовый разнотравно-вальдштейниевый
леc, 12 VII 2014, МИ, ID 36281, 36282 (ALTB). Бурятия, долина р. Выдриная, смешанный до
линный лес с травяным покровом, 11 VIII 2008,
МИ, ID 35771, 35772, 35773 (ALTB). Lathyrus gmelinii Fritsch (Fabaceae) – южноси
бирский вид. Встречается на западе Иркутской
обл. и на юге Бурятии. Приводится для Бай
кальского заповедника без указания конкретных
местонахождений (Vasilchenko et al., 1978; Kras
nopevtseva et al., 2006; Abramova, Volkova, 2011). Cotoneaster lucidus Schlecht. (Rosaceae) – эн
дем Южного Прибайкалья (Kurbatskiy, 1988). Широко используется в озеленении. Отмечен
на крайнем западе юго-восточного побережья: г. Слюдянка, ост. п. Сухой Ручей, ост. п. Буравщи
на, р. Безымянная (Ivanova, 1999). p
,
;
,
,
)
Приводим новые местонахождения. Респу
блика Бурятия: район р. Переёмная, нижнее те
чение р. Селенгушка (Селенгинка), на насыпи
ж. д., 27 VI 1973, Н. Коваленко, № 515 (NSK); р. Переёмная, разнотравный луг, 22 VII 1990, ано
ним, ID 12398; р. Мишиха, в темнохвойном лесу,
1985, АК, ID 12343; там же, в 9 км от устья, по
галечнику, 12 VII 1973, АК, З. Д. Малышева, №
900 (NSK); там же, левобережье, в 10 км вверх по
течению, в смешанном лесу, 14 VI 1975, АК, Н. В. Власова, № 8 (NSK); правобережье р. Миши
ха, в 3–3,5 км от тракта, вдоль тропы в пихтовом
лесу, 04 X 2009, МИ, ID 35749, 35853 (ALTB); р. Редкие виды В. Степанцова, ID 20121;
ст. Мурино, в березняке, 22 VI 1974, АК, № 222
(NSK). Бурятия: р. Большой Мамай, около реки
на камнях, 24 VII 1957, МИ (NSK); там же, лес
ной пояс, по берегу речки, 06 VIII 2006, МИ, ID
35698; р. Выдриная, на мокром песке по бере
гу старицы, 10 VIII 2008, МИ, ID 35697; окр. ст. Приводим новые местонахождения. Иркут
ская обл.: ост. п. Сухой Ручей, на осоковом боло
те, 03 VIII 1974, АК, № 1911 (NSK); ст. Утулик,
берег реки, на переувлажненном лугу, 23 VII
1974, АК, № 1262 (NSK); между р. Малые Ман
гылы и ст. Выдрино, 5379-й км, пикет 7, мокрая 100 Иванова М. М. и др. Иванова М. М. и др. Находки во флоре юго-восточного побережья Байкала Иванова М. М. и др.
Находки во флоре юго-восточного побережья Байкала Ивановка, в 7 км вверх от устья, в редкостойном
смешанном лесу, 10 VII 1975, АК, Н. В. Власова,
№ 304 (NSK); р. Мысовка, низовья, на лесном Сообщаем еще один пункт на этом побережье –
самый восточный: устье р. Бабха, топольник, 28
IX 2006, МИ, ID 37795, 37796 (ALTB). Образцы
без плодов, определены по листьям. Cotoneaster uniflorus Bunge (Rosaceae) – рас
пространен в Европейской части России, Запад
ной и Восточной Сибири, Средней Азии, Мон
голии (Kurbatskiy, 1988). На Байкале обнаружен
близ с. Сарма на западном побережье (Ivanova,
2003). А. С. Краснопевцева с соавторами (Kras
nopevtseva et al., 2006), а также Л. А. Абрамова
и П. А. Волкова (Abramova, Volkova, 2011) при
водят этот вид для высокогорий Байкальского
заповедника. Это указание требует подтвержде
ния, гербарных образцов мы не видели. Turczaninowia 19 (3): 94–105 (2016) 101 лугу, 31 VII 1987, Н. В. Фризен, № 1666 (NSK);
там же, 9 км от устья, в пойменном смешанном
лесу, 19 VII 1975, АК, Н. В. Власова, № 498
(NSK); ст. Боярск, 10 км к югу, 18 VIII 1975, АК,
№ 1091 (NSK). ское изучение распространения данного вида на
территории Сибири. ское изучение распространения данного вида на
территории Сибири. Приводим наши данные: Республика Буря
тия, окр. д. Толбазиха, р. Толбазиха, левый бе
рег, кедрово-пихтово-березовый чернично-раз
нотравный лес с елью, абс. выс. 566 м, СК, 14
VII 2014, ID 36232–36234, 36235, 36235 (VLA),
36236 (ALTB), 36337 (NSK). Hypericum ascyron L. (Hypericaceae) – аме
рикано-азиатский вид. На берегах Байкала со
бирался редко. В «Конспекте флоры Иркутской
области» (Check-list of the vascular ..., 2008) при
водится для п. Култук по сборам Г. И. Поплав
ской в 1916 г. Mentha arvensis L. (Lamiceae) – циркумполяр
ный вид. На юго-восточном побережье приво
дится для Байкальского заповедника без указа
ния конкретных местонахождений (Vasilchenko
et al., 1978). Приводим этикеточные данные образцов. Ир
кутская обл.: р. Култучная, старый тракт в Тун
кинскую долину, у подножья скалистого остеп
ненного склона, 18 VII 1998, МИ, ID 35705; р. Снежная, левобережье, в 4 км от Карьерских
озер, березово-кедровый лес, у ручья, 21 VIII
2001, СК, ID 7320, 7321 (NS). Бурятия, р. Пере
ёмная, низовье, пойма, высокотравье, 09 VII
1994, СК, ID 36410, 36411. Приводим наши данные: Иркутская обл., р. Слюдянка, в 2–3 км от устья, на поляне, 01 VIII
1993, МИ. Бурятия, ст. Танхой, на берегу озерка,
21 VIII 1981, АК, ID 43424; там же, 21 VII 2008,
А. С. Краснопевцева, ID 5781. M. canadensis L. Иванова М. М. и др.
Находки во флоре юго-восточного побережья Байкала (Lamiaceae) – американо-
азиатский вид. Для юго-восточного побережья
Байкала не приводится. Цитируем образцы, хра
нящиеся в Гербариях NSK и IRKU. Иркутская
обл.: в приустьевой части р. Слюдянки, на окра
ине огорода, 07 VIII 1992, МИ (IRKU); ст. Слю
дянка, на проселочной дороге, 04 VIII 1974, АК,
№ 2049 (NSK); ост. п. Сухой Ручей, на проселоч
ной дороге, 25 VIII 1974, АК, № 2283 (NSK); окр. п. Выдрино, на насыпи ж. д., 18 VIII 1973, АК,
Н. В. Власова, № 1977 (NSK). Судя по местооби
таниям в этом районе вид заносный. В гербарии
IRK имеются образцы из близлежащих районов,
собранные в естественных местообитаниях – в
зарослях кустарников, на лугах, по берегам рек,
например, р. Тибельти в западных предгорьях
Хамар-Дабана, с. Мостовка, с. Татаурова в ни-
зовьях р. Селенга. M. canadensis L. (Lamiaceae) – американо-
азиатский вид. Для юго-восточного побережья
Байкала не приводится. Цитируем образцы, хра
нящиеся в Гербариях NSK и IRKU. Иркутская
обл.: в приустьевой части р. Слюдянки, на окра
ине огорода, 07 VIII 1992, МИ (IRKU); ст. Слю
дянка, на проселочной дороге, 04 VIII 1974, АК,
№ 2049 (NSK); ост. п. Сухой Ручей, на проселоч
ной дороге, 25 VIII 1974, АК, № 2283 (NSK); окр. Epilobium davuricum Fisch. ex Hornem. (Ona
graceae) – преимущественно североазиатский
вид, за пределами Азии встречается на севере
Европы и Северной Америки (Skvortsov, 1996;
Vlasova, 1996). На берегах Байкала не отмечался
(Vasilchenko et al., 1978; Check-list of the vascular
..., 2008). Для юго-восточного побережья Байкала при
водится впервые: Бурятия, левобережье р. Ми
шихи близ устья, на галечнике, 03 X 2009, МИ,
ID 35708. Trientalis arctica Fisch. ex Hook. (Primulaceae) –
преимущественно
северопацифический
вид,
распространенный на побережьях Тихого оке
ана российского Дальнего Востока, Северной
Америки и Японии (Probatova, 1987). Во «Флоре
СССР» (Gorshkova, 1952) для этого вида указаны
Ангаро-Саянский и Даурский флористические
районы Восточной Сибири. Во «Флоре Сибири»
(Kovtonyuk, 1997) отмечается, что нахождение T. arctica в Сибири не подтверждено гербарными
материалами. Однако экземпляры из приводи
мого нами пункта, несомненно, относятся к T. arctica. В отличие от T. europaea L., они харак
теризуются бóльшим числом стеблевых листьев
(8–12), листья плотные и кожистые; цветонож
ки в верхней части густо железистоопушенные. Характерной особенностью собранных экзем
пляров является наличие боковых и подверху
шечных ветвей, наличие которых не отмечено в
известных нам описаниях. Необходимо критиче Ареалы Mentha arvensis и M. canadensis в
Центральной Сибири частично перекрываются. Limosella aquatica L. (Scrophulariaceae) –
почти космополитный вид. Местонахождения
в Центральной Сибири немногочисленны. Иванова М. М. и др.
Находки во флоре юго-восточного побережья Байкала 28 VIII 1998, МИ, СК, ID 36416. Бурятия: р. Ива
новка, нижнее течение, на берегу озерка, 17 VII
1975, АК, Н. В. Власова, № 487 (NSK); ст. Клю
евка, на дне высыхающего болотца, 06.VII.1975,
АК, Н. В. Власова, № 249 (NSK). Campanula cervicaria L. (Campanulaceae) – ев
ро-сибирский вид. В Центральной Сибири про
ходит восточная граница распространения. На
юго-восточном побережье Байкала, возможно,
является заносным растением. Приводится для
ст. Утулик, рек Мысовая, Мантуриха, Тельная
(Kiseleva, 1977; Flora of Central.., 1979). В Бай
кальском заповеднике редок (Krasnopevtseva et
al., 2006; Abramova, Volkova, 2011). Utricularia intermedia Hayne (Lentibularia-
ceae) – циркумполярный гидрофит. На Байкале
отмечен на северо-западном побережье – в бухте
Баргунда (Ivanova, 1991) и на мысу Большой Со
лонцовый. На юго-восточном побережье не от
мечался (Vasilchenko et al., 1978; Check-list of the
vascular.., 2008). Приводим еще несколько местонахождений. Бурятия: ст. Выдрино, на поляне в лесу, 13 VIII
1973, AK, С. Павар, № 1829 (NSK); между ост. п. Мамай и р. Осиновкой, на дороге ниже ж. д. на
сыпи, 03 VIII 2006, МИ, ID 35794; ст. Кедровая,
в смешанном лесу, 07 VIII 1981, AK, ID 36513. Приводим еще несколько местонахождений. Бурятия: ст. Выдрино, на поляне в лесу, 13 VIII
1973, AK, С. Павар, № 1829 (NSK); между ост. п. Мамай и р. Осиновкой, на дороге ниже ж. д. на
сыпи, 03 VIII 2006, МИ, ID 35794; ст. Кедровая,
в смешанном лесу, 07 VIII 1981, AK, ID 36513. Приводим этикеточные данные образцов. Ир
кутская обл.: окр. г. Слюдянка, озеро за берего
вым валом Байкала, 27 VI 2004, МИ, ID 33149,
33151, 33152; ост. п. Сухой Ручей, на осоковом
болоте, 03 VIII 1974, АК, № 1922 (NSK); р. Бабха
близ устья, лужица за береговым валом Байкала,
28 IX 2006, МИ, ID 33154, 33155; ст. Утулик, в
водоеме, 11 VII 1974, АК, Н. В. Власова, № 1180
(NSK); р. Большие Мангылы, 16 VII 1974, АК,
№ 488 (NSK). Бурятия: р. Большой Мамай, за бе
реговым валом Байкала, на окраине болота, 30
VIII 1995, МИ, ID 36425; ост. п. Речка Выдриная,
небольшое озеро у ж. д. моста, в воде, 27 VIII
2010, Ю. Н. Починчик, ID 22132; ст. Боярск, в
воде озерка, 12 VII 1975, АК, Н. Золотуева, №
243 (NSK), там же, 19 VIII 1975, АК, Н. В. Вла
сова, № 1125 (NSK); ст. Посольск, 19 VII 1952,
Л. В. Бардунов, И. И. Андреева (NSK); там же,
озерко, 2 VI 1987, АК, ID 36426. Иванова М. М. и др.
Находки во флоре юго-восточного побережья Байкала Pilosella dublitzkii (B. Fedtsch. et Nevski) Sen
nik. (Asteraceae) – распространен в Средней
Азии (Тарбагатай, Джунгарский Алатау, Тянь-
Шань), в горных районах юга Западной Сиби
ри и прилегающих районах Восточной Сибири
(Красноярский край, Хакасия, Тува), из Южной
Бурятии приводится для хребта Улан-Бургасы
(Tupitsyna, 2004). В Гербарии им. М. Г. Попова (NSK) имеют
ся 2 образца, определенных Н. Н. Тупицыной в
2000 и 2003 гг., тоже относящихся к Южной Бу
рятии: в 3 км к западу от ост. п. Переёмная, на
откосе ж. д., 24 VI 1973, AK, № 445 (NSK); окр. ост. п. Клюевка, на луговом склоне, 4 VII 1975,
АК, Н. В. Власова, № 171 (NSK). Иванова М. М. и др.
Находки во флоре юго-восточного побережья Байкала На
Байкале известен с юго-западного побережья:
устье р. Голоустная (Ivanova, Azovsky, 1998) и р. Улан-Хан (Check-list of the vascular …, 2008). На
юго-восточном побережье Байкала обнаружен в
устье р. Мишихи (Krasnopevtseva et al.., 2006). Limosella aquatica L. (Scrophulariaceae) –
почти космополитный вид. Местонахождения
в Центральной Сибири немногочисленны. На
Байкале известен с юго-западного побережья:
устье р. Голоустная (Ivanova, Azovsky, 1998) и р. Улан-Хан (Check-list of the vascular …, 2008). На
юго-восточном побережье Байкала обнаружен в
устье р. Мишихи (Krasnopevtseva et al.., 2006). Иркутская обл.: ст. Утулик, лужицы на галеч
ной дамбе между сливными водоемами БЦБК,
29 VIII 1991, МИ, ID 35711; берег р. Хара-Мурин
в 3 км выше ст. Мурино, у лесной дороги, в луже, 102 Иванова М. М. и др. Находки во флоре юго-восточного побережья Байкала REFERENCES / ЛИТЕРАТУРА Т. 18. М.; Л.: Изд-во АН СССР, 1952. С. 269 –272). Gureyeva, I. I. (2001) Homosporous ferns of South Siberia. Taxonomy, origin, biomorphology, population biol
ogy. Tomsk State University Publishers, Tomsk, 158 pp. [In Russian]. (Гуреева И. И. Равноспоровые папоротники
Южной Сибири. Систематика, происхождение, морфология, популяционная биология. Томск: Изд-во Томск. ун-та, 2001. 158 с.). Ivanova, M. M. (1981) The findings in the flora of Baikalo-Patomskoye highland. Bot. Zhurn. (Moscow, Lenin
grad) 66(3): 447–455 [In Russian] (Иванова М. М. Находки во флоре Байкало-Патомского нагорья // Бот. журн.,
1981. Т. 66, № 3. C. 447–455).il Ivanova, M. M. (1991) New findings in the flora of the Cisbaikalian region and southern Transbaikalian region. Bot. Zhurn. (Moscow, Leningrad) 76(7): 1007–1016 [In Russian]. (Иванова М. М. Находки во флоре Прибайкалья
и Южного Забайкалья // Бот. журн., 1991. Т. 76, № 7. С. 1007–1016).il Ivanova, M. M. (1999) The findings in the flora on the shores of lake Baikal, the southern part of Angara and
headwaters of the river Lena. Turczaninowia 2, 3: 28–40 [In Russian]. (Иванова М. М. Находки во флоре берегов
оз. Байкал, Южного Приангарья и верхнего течения р. Лены // Turczaninowia, 1999. Т. 2, вып. 3. С. 28–40).li Ivanova, M. M. (2003) The floristic findings in vicinities of the Baikal lake and the neighboring territories. Tur
czaninowia 6, 2: 71–78 [In Russian]. (Иванова М. М. Флористические находки на Байкале и в Прибайкалье //
Turczaninowia, 2003. Т. 6, вып. 2 C. 71–78). Ivanova, M. M., Azovskiy, M. G. (1998) Floristic records in Buryatia and Irkutsk region. Bot. Zhurn. (Moscow, St. Peterburg) 83(5): 119–124 [In Russian]. (Иванова М. М., Азовский М. Г. Флористические находки в Бурятии и
Иркутской области // Бот. журн., 1998. Т. 83, № 5. С. 119–124).l р у
ур
)
Kazanovsky, S. G. (2003) Relict bryophytes in the flora of the Khamar-Daban range. In: Botanicheskie issle
dovaniya v aziatskoy Rossiiv: Materialy XI syezda Russkogo botanicheskogo obshchestva (18–22 avgusta 2003 g.,
Novosibirsk – Barnaul) [Botanical studies in the Asian Russia: Proceedings of the XI Congress of Russian Botanical
Society (18–22 August, 2003 Novosibirsk – Barnaul)]. AzBuka Press, Barnaul. 1: 206–207 [In Russian]. (Казанов
ский С. Г. Реликтовые мохообразные во флоре хребта Хамар-Дабан // Ботанические исследования в азиатской
России: Материалы XI съезда Русского ботанического общества (18–22 августа 2003 г., Новосибирск – Барна
ул). Т. 1. Барнаул: Изд-во АзБука, 2003. С. 206–207).l Kiseleva, A. A. REFERENCES / ЛИТЕРАТУРА Abramova, L. A., Volkova, P. A. (2011) Vascular plants of the Baikal reservation (check-list of species). In: Flora
and fauna of the reservations. Dobrosvet, Moscow, 117: 112 [In Russian]. (Абрамова Л. А., Волкова П. А. Сосуди
стые растения Байкальского заповедника (аннотированный список видов) // Флора и фауна заповедников. М.:
Добросвет, 2011. Вып. 117. 112 с.). Alekseyev, E. B. (1990) Festuca L. – Fescue. In: Flora Sibiri [Flora of Siberia]. Nauka, Novosibirsk, 2: 130–162
[In Russian]. (Алексеев Е. Б. Festuca L. – Овсяница // Флора Сибири. Новосибирск: Наука, 1990. Т. 2. С. 130–
162). Bardunov, L. V. (1963) Tertiary relicts of the flora of mosses Baikal area. In: Nauchnye chteniya pamyati Mikhaila
Grigoryevicha Popova (5-e chtenie) [Scientific Readings in Memory of Michail G. Popov (5th Reading)]. Irkutsk,
48–82 [In Russian]. (Бардунов Л. В. Третичные реликты во флоре мхов Прибайкалья // Научные чтения памяти
Михаила Григорьевича Попова (5-е чтение). Иркутск, 1963. С. 48–82).l Check-list of the vascular flora of the Irkutsk region. (2008) Ed. L.I. Malyshev. Publishing of Irkutsk State Univer
sity, Irkutsk, 327 pp. [In Russian]. (Конспект флоры Иркутской области (сосудистые растения) / Под ред. Л. И. Малышева. Иркутск: Изд-во Иркут. ун-та, 2008. 327 с.).i Epova, N. A. (1956) The relicts of the broad-leaved forests in the fir-taiga of the mountain Khamar-Daban. In:
Izvestiya Biologo-geograficheskogo nauchno-issledovatelskogo instituta pri Irkutskom gosudarstvennom universitete
[The news of the biology-geographical institute by the Irkutsk state university] 15, 1–4: 25–62 [In Russian]. (Епова
Н. А. Реликты широколиственных лесов в пихтовой тайге Хамар-Дабана // Изв. Биол.-географ. н.-и. инст. при
Иркутском гос. унив., 1956. Т. 15, вып. 1–4. С. 25–62). Turczaninowia 19 (3): 94–105 (2016) 103 Flora of Central Siberia. (1979) Eds. L. I. Malyshev, G. A. Peshkova. Nauka, Novosibirsk, 1, 536 pp.; 2. 541–1048
[In Russian]. (Флора Центральной Сибири / Под ред. Л. И. Малышева, Г. А. Пешковой. Новосибирск: Наука,
1979. Т.1. 536 с.; Т.2. С. 541–1048). Flora of Russian Far East: Addenda and corrigenda to “Vascular plants of the Soviet Far East.” Vol. 1–8 (1985–
1996). (2006) Dalnauka, Vladivostok, 456 pp. [In Russian]. (Флора российского Дальнего Востока: Дополнения и
изменения к изданию «Сосудистые растения советского Дальнего Востока». Т. 1–8 (1985–1996). Владивосток:
Дальнаука, 2006. 456 с.). Gorshkova, S. G. (1952) The genus Starflower – Trientalis. In: Flora URSS [Flora of USSR]. Pablishers of Acad
emy of Sciences of USSR, Moscow, Leningrad. 18: 269–272 [In Russian] (Горшкова С. Г. Род Седмичник – Trien
talis L. // Флора СССР. REFERENCES / ЛИТЕРАТУРА yl
]
y
pp [
]
(Положий А. В., Крапивкина Э. Д. Реликты третичных широколиственных лесов во флоре Сибири. Томск:
Изд-во Том. ун-та, 1985. 156 с.). Popov, M. G. (1955) Flora of Baikal Siberia and its origin // Novaya Sibir [New Siberia]. Irkutsk 33: 302–319 [In
Russian]. (Попов М. Г. Флора байкальской Сибири и ее происхождение // Новая Сибирь. Иркутск, 1955. Вып. 33. С. 302–319). Popov, M. G. (1957) Flora Sredney Sibiri [Flora of the Middle Siberia]. Publishers of Academy of Sciences of
USSR, Moscow, Leningrad. Vol. 1. 556 pp. [In Russian]. (Попов М. Г. Флора Средней Сибири. М.; Л.: Изд-во АН
СССР, 1957. Т. 1. 556 с.). Probatova, N. S. (1987) Primrose Family – Primulaceae. In: Sosudistye rasteniya sovetskogo Dalnego Vostoka
[Vascular plants of the Soviet Far East]. Nauka, Leningrad. 2: 138–170 [In Russian]. (Пробатова Н. С. Семейство
Первоцветные – Primulaceae // Сосудистые растения советского Дальнего Востока. Л.: Наука, 1987. Т. 2. С. 138–170). Red Book of Krasnoyarsk Territory: Plants and funges. (2005) Polikon, Krasnoyarsk. 368 pp. [In Rus
ная книга Красноярского края: Растения и грибы. Красноярск: Поликон, 2005. 368 с.). Red Data Book of Republic of Buryatia. Rare and Endangered Species of Animals, Plants and Fungi. (2013)
Buryat Scientific Center of Siberian Branch of Russian Academy of Sciences Publisher, Ulan-Ude, 688 pp. [In Rus
sian]. (Красная книга Республики Бурятия: Редкие и находящиеся под угрозой исчезновения виды животных,
растений и грибов. Улан-Удэ: Изд-во БНЦ СО РАН, 2013. 688 с.). Skvortsov, A. K. (1996) Onagraceae. In: Flora Vostochnoy Evropy [Flora of Eastern Europe]. Mir i semja-95, St. Peterburg. 9: 299–316 [In Russian]. (Скворцов А. К. Сем. Onagraceae – Ослинниковые, Кипрейные // Флора Вос
точной Европы. СПб.: Мир и семья-95, 1996. Т. 9. С. 299–316).i Stepanov, N. V. (1997) On the problem of the relict nature of Veronica officinalis (Scrophulariaceae) in the south
Siberia mountains. Bot. Zhurn. (Moscow, St. Peterburg) 82(12): 41–45 [In Russian]. (Степанов Н. В. К вопросу о
реликтовой природе Veronica officinalis (Scrophulariaceae) в горах юга Сибири // Бот. журн., 1997. T. 82, № 12. С. 41–45). Tupitsyna, N. N. (1992) Truellum Houtt. In: Flora Sibiri [Flora of Siberia]. Nauka, Novosibirsk, 5: 117 [In Rus
sian]. (Тупицына Н. Н. Truellum Houtt. – Колючестебельник // Флора Сибири. Новосибирск: Наука, 1990. Т. 5. С. 117). Tupitsyna, N. N. (2004) Yastrebinki Sibiri [Hawkweeds of Siberia]. Nauka, Novosibirsk, 208 pp. [In Russian]. (Тупицына Н. Н. Ястребинки Сибири. Новосибирск: Наука, 2004. 208 с.). REFERENCES / ЛИТЕРАТУРА C. 35–170). shev, L. I. (1990) Carex L. – Sedge. Flora Sibiri [Flora of Siberia]. Nauka, Novosibirsk, 3: 35–170 [In Ru ,
(
)
g
[
f
]
,
,
[
алышев Л. И. Carex L. – Осока // Флора Сибири. Новосибирск: Наука, 1990. Т. 2. C. 35–170). Malyshev, L. I., Peshkova, G. A. (1979) Nuzhdayutsya v okhrane – redkie i ischezayushchie rasteniya Zentralnoy
Sibiri [They need guarding – rare and disappearing plans of the Central Siberia]. Nauka, Siberian Branch, Novosi
birsk, 173 рp. [In Russian]. (Малышев Л. И., Пешкова Г. А. Нуждаются в охране – редкие и исчезающие рас
тения Центральной Сибири. Новосибирск: Наука. Сибирское отделение, 1979. 173 с.).l Malyshev, L. I., Peshkova, G. A. (1984) Osobennosti i genezis flory Sibiri (Predbaykalye i Zabaykalye) [Features
and genesis of the flora of Siberia (Cisbaikalia and Transbaikalia)]. Nauka, Siberian Branch, Novosibirsk, 264 рp. [In
Russian]. (Малышев Л. И., Пешкова Г. А. Особенности и генезис флоры Сибири (Предбайкалье и Забайкалье). Новосибирск: Наука, Сибирское отделение, 1984. 264 с.). Olonova, M. V. (1990) Poa L. – Bluegrass. In: Flora Sibiri [Flora of Siberia]. Nauka, Novosibirsk, 2: 163–186
[In Russian]. (Олонова М. В. Poa L. – Мятлик // Флора Сибири. Новосибирск: Наука, 1990. Т. 2. C. 163–186). Olonova, M. V. (1990) Poa L. – Bluegrass. In: Flora Sibiri [Flora of Siberia]. Nauka, Novosibirsk, 2: 163–186
[In Russian]. (Олонова М. В. Poa L. – Мятлик // Флора Сибири. Новосибирск: Наука, 1990. Т. 2. C. 163–186). Polozhij, A. V. (1996) Veronica L. – Veronica. In: Flora Sibiri [Flora of Siberia]. Nauka, Novosibirsk, 12: 26–47
[In Russian]. (Положий А. В. Veronica L. – Веронника // Флора Сибири. Новосибирск: Наука, 1996. Т. 12. C. 26–47).l Polozhij, A. V. (1996) Veronica L. – Veronica. In: Flora Sibiri [Flora of Siberia]. Nauka, Novosibirsk, 12: 26–47
[In Russian]. (Положий А. В. Veronica L. – Веронника // Флора Сибири. Новосибирск: Наука, 1996. Т. 12. C. 26–47).l Polozhij, A. V., Krapivkina, E. D. (1985) Relicty tretichnykh shirokolistvennykh lesov vo flore Sibiri
of tertiary deciduous forests in the flora of Siberia]. Tomsk State University Publishers, Tomsk, 156 pp. Polozhij, A. V., Krapivkina, E. D. (1985) Relicty tretichnykh shirokolistvennykh lesov vo flore Sibiri [The relicts
of tertiary deciduous forests in the flora of Siberia]. Tomsk State University Publishers, Tomsk, 156 pp. [In Russian]. (Положий А. В., Крапивкина Э. Д. Реликты третичных широколиственных лесов во флоре Сибири. Томск:
Изд-во Том. ун-та, 1985. 156 с.). REFERENCES / ЛИТЕРАТУРА (1978) Nemoral relicts in the flora of the southern coast of the lake Baikal. Bot. Zhurn. (Moscow,
Leningrad) 63(11): 1647–1656 [In Russian]. (Киселева А. А. Неморальные реликты во флоре южного побережья
озера Байкал // Бот. журн., 1978. Т. 63, № 11. С. 1647–1656). Kiseleva, A. A., Bardunov, L. V., Makryj, T. V. (1990) Vascular plants. In: Unic objects of the alive nature of the
Baikal basin. Nauka, Siberian Branch, Novosibirsk: 51–67 [In Russian]. (Киселева А. А., Бардунов Л. В., Макрый
Т. В. Сосудистые растения // Уникальные объекты живой природы бассейна Байкала. Новосибирск: Наука,
Сибирское отделение, 1990. С. 51–67). р
)
Kovtonyuk, N. K. (1997) Primulaceae – Primrose Family. In: Flora Sibiri [Flora of Siberia]. Nauka, Novosibirsk,
11: 30–47 [In Russian]. (Ковтонюк Н. К. Семейство Primulaceae – Примуловые // Флора Сибири. Новосибирск:
Наука, 1997. T. 11 C. 30–47). Krasnaya kniga Irkutskoy oblasti: Sosydistye rasteniya [Red Data Book of the Irkutsk region. Vascular plants]. (2001) Oblmachinform, Irkutsk, 200 pp. [In Russian]. (Красная книга Иркутской области. Сосудистые растения. Иркутск: Облмашинформ, 2001. 200 с.). Krasnaya kniga Irkutskoy oblasti [Red Data Book of the Irkutsk region]. (2010) Vremya Stranstviy, Irkutsk, 480
pp. [In Russian]. (Красная книга Иркутской области. Иркутск: Время странствий, 2010. 480 с.). Krasnaya kniga Respubliki Butyatia. Redkie i ischezayushchie vidy rasteniy i gribov [Red Data Book of Republic
of Buryatia. Rare and disappearing species of plants and fungi]. (2002) Nauka, Novosibirsk. 340 pp. [In Russian]. (Красная книга Республики Бурятия. Редкие и исчезающие виды растений и грибов. Новосибирск: Наука,
2002. 340 с.). Krasnopevtseva, A. S., Martusova, E. G., Krasnopevtseva, V. M. (2006) Kadastr sosudistych rasteniy Baikalskogo
zapovednika [Check-list of the vascular plants of the Baikal reservation]. Reprocetnr A1, Irkutsk, 60 pp. [In Russian]. (Краснопевцева А. С., Мартусова Е. Г., Краснопевцева В. М. Кадастр сосудистых растений Байкальского за
поведника. Иркутск: Репроцентр А1, 2006. 60 с.). 104 Иванова М. М. и др. Находки во флоре юго-восточного побережья Байкала Иванова М. М. и др. Иванова М. М. и др. Kurbatskiy, V. I. (1988) Cotoneaster Medicus – Cotoneaster. In: Flora Sibiri [Flora of Siberia]. Nauka, Novo
sibirsk, 8: 21–25 [In Russian]. (Курбатский В. И. Cotoneaster Medicus – Кизильник // Флора Сибири. Новоси
бирск: Наука, 1988. T. 8. C. 21–25). р
у
,
)
Malyshev, L. I. (1990) Carex L. – Sedge. Flora Sibiri [Flora of Siberia]. Nauka, Novosibirsk, 3: 35–170 [In Rus
sian]. (Малышев Л. И. Carex L. – Осока // Флора Сибири. Новосибирск: Наука, 1990. Т. 2. Иванова М. М. и др.
Находки во флоре юго-восточного побережья Байкала Vlasova, N. V. (1996) Onagraceae – Evening-primrose Family. In: Flora Sibiri [Flora of Siberia]. Nauka, No
vosibirsk, 10: 106–120 [In Russian]. (Власова Н. В. Семейство Onagraceae – Кипрейные, или Ослинниковые //
Флора Сибири. Новосибирск: Наука, 1996. Т. 10. С. 106–120). р
р
р
у
,
)
Zarubin, A. M., Ivanova, M. M., Lyakhova, I. G., Baritskaya, V. A., Ivelskaya, V. I. (1993) Floristic finding in
Cisbaikalia. Bot. Zhurn. (Moscow, St. Peterburg) 78(8): 93–101 [In Russian]. (Зарубин А. М., Иванова М. М, Ля
хова И. Г., Барицкая В. А., Ивельская В. И. Флористические находки в Прибайкалье // Бот. журн., 1993. Т. 78,
№ 8. С. 93–101). Vlasova, N. V. (1996) Onagraceae – Evening-primrose Family. In: Flora Sibiri [Flora of Siberia]. Nauka, No
vosibirsk, 10: 106–120 [In Russian]. (Власова Н. В. Семейство Onagraceae – Кипрейные, или Ослинниковые //
Флора Сибири. Новосибирск: Наука, 1996. Т. 10. С. 106–120).
Zarubin, A. M., Ivanova, M. M., Lyakhova, I. G., Baritskaya, V. A., Ivelskaya, V. I. (1993) Floristic finding in
Cisbaikalia. Bot. Zhurn. (Moscow, St. Peterburg) 78(8): 93–101 [In Russian]. (Зарубин А. М., Иванова М. М, Ля
хова И. Г., Барицкая В. А., Ивельская В. И. Флористические находки в Прибайкалье // Бот. журн., 1993. Т. 78,
№ 8. С. 93–101). Turczaninowia 19 (3): 94–105 (2016) REFERENCES / ЛИТЕРАТУРА Turczaninow, N. S. (1856) Flora baicalensi-dahurica seu descriptio plantarum in regionibus cis- et transba
icalensibus atque in Dahuria sponte nascetium. Mosquae. 2, 2. 374 pp. Tzvelev, N. N. (1974) Poaceae (Graminea). In: Flora Yevropeyskoy chasti SSSR [Flora of the European part of
the USSR]. – Nauka, Leningrad. 1: 117–368 [In Russian]. (Цвелев Н. Н. Сем. Poaceae (Graminea) – Злаки // Флора
Европейской части СССР. Л.: Наука, 1974. Т. 1. С. 117–368). р
у
)
Vasilchenko, Z. A., Ivanova, M. M., Kiseleva, A. A. (1978) Overview of higher plant species of Baikalskiy Re
serve. In: Flora Pribaykalya [Flora of Cisbaikal]. Nauka, Siberian Branch, Novosibirsk: 49–114 [In Russian]. (Ва
сильченко З. А., Иванова М. М., Киселева А. А. Обзор видов высших растений Байкальского заповедника //
Флора Прибайкалья. Новосибирск: Наука, Сибирское отделение, 1978. С. 49–114). Turczaninowia 19 (3): 94–105 (2016) 105
|
https://openalex.org/W2584847583
|
http://cds.cern.ch/record/2296673/files/pdf.pdf
|
English
| null |
Automatised data quality monitoring of the LHCb Vertex Locator
|
Journal of physics. Conference series
| 2,017
|
cc-by
| 4,110
|
Related content Related content
The LHCb vertex locator
O Behrendt
-
The LHCb Vertex Locator — performance
and radiation damage
A Oblakowska-Mucha
-
The LHCb Vertex Locator (VELO) Pixel
Detector Upgrade
E. Buchanan
- Journal of Physics: Conference Series Journal of Physics: Conference Series This content was downloaded from IP address 188.184.3.52 on 07/12/2017 at 10:54 E:mail: szumlak@agh.edu.pl Abstract. The LHCb Vertex Locator (VELO) is a silicon strip semiconductor detector
operating at just 8mm distance to the LHC beams. Its 172,000 strips are read at a frequency of
1.1 MHz and processed by off-detector FPGAs followed by a PC cluster that reduces the
event rate to about 10 kHz. During the second run of the LHC, which lasts from 2015 until
2018, the detector performance will undergo continued change due to radiation damage effects. This necessitates a detailed monitoring of the data quality to avoid adverse effects on
the physics analysis performance. The VELO monitoring infrastructure has been re-designed
compared to the first run of the LHC when it was based on manual checks. The new
system is based around an automatic analysis framework, which monitors the performance of
new data as well as long-term trends and using dedicated algorithms flags issues whenever
they arise. The new analysis framework then analyses the plots that are produced by these
algorithms. One of its tasks is to perform custom comparisons between the newly processed
data and that from reference runs. The most-likely scenario in which this analysis would
identify an issue is the parameters of the readout electronics no longer being optimal and
requiring retuning. The data of the monitoring plots can be reduced further, e.g. by evaluating
averages, and these quantities are input to long-term trending. This is used to detect slow
variation of quantities, which are not detectable by the comparison of two nearby runs. Such
gradual change is what is expected due to radiation damage effects. It is essential to detect
these changes early such that measures can be taken, e.g. adjustments of the operating
voltage, to prevent any impact on the quality of high-level quantities and thus on physics
analyses. The plots as well as the analysis results and trends are made available through
graphical user interfaces (GUIs). These GUIs are dynamically configured by a single
configuration that determines the choice and arrangement of plots and trends and ensures a
common look and feel. Automatised data quality monitoring of the LHCb
Vertex Locator To cite this article: L. Bel et al 2017 J. Phys.: Conf. Ser. 898 092046 View the article online for updates and enhancements. This content was downloaded from IP address 188.184.3.52 on 07/12/2017 at 10:54 CHEP CHEP 1234567890
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 1234567890
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046 1
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution
of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Published under licence by IOP Publishing Ltd L. Bel1, A.Ch. Crocombe2, M. Gersabeck3, A. Pearce3, M. Majewski4 and
T. Szumlak4 L. Bel1, A.Ch. Crocombe2, M. Gersabeck3, A. Pearce3, M. Majewski4 and
T. Szumlak4 L. Bel1, A.Ch. Crocombe2, M. Gersabeck3, A. Pearce3, M. Majewski4 and
T. Szumlak4 1 Nikhef National Institute (NL), 1 Nikhef National Institute (NL), 2 University of Warwick (BG), 3 University of Manchester (GB),
4 AGH – UST Krakow (PL) E:mail: szumlak@agh.edu.pl Automatised data quality monitoring of the LHCb Vertex
Locator L. Bel1, A.Ch. Crocombe2, M. Gers
T. Szumlak4
1 Nikhef National Institute (NL),
2 University of Warwick (BG),
3 University of Manchester (GB),
4 AGH – UST Krakow (PL) L. Bel1, A.Ch. Crocombe2, M. Gersabeck3, A. Pearce3, M. Majewski4 and
T. Szumlak4
1 Nikhef National Institute (NL),
2 University of Warwick (BG),
3 University of Manchester (GB),
4 AGH – UST Krakow (PL) 1 Because of the historical reasons the part of the experimental Data Acquisition system (DAQ) responsible for
compressing the raw data stream and buffering is called Tell1 (Trigger Electronics Level 1).
2 The HLT output rate during the regular data taking amounts to approximately 12.5 kHz. 2. Monitoring software platform for VELO In this Section the overall architecture of the monitoring platform is presented. For completeness, we
begin with short description of the engine application, VETRA [3], that is used to process the raw data
banks. The main output of VETRA consists of ROOT histograms that are subsequently fed to the
monitoring application called Lovell. By splitting the data processing and monitoring we make the
software more reliable and robust. The main assumption here is that the VETRA output is final and do
not undergo any further processing and Lovell is used only for visualization, data quality assessment
and trending. 2.1. VETRA This part of the VELO software platform, which is integrated within the official LHCb framework, uses
directly the raw experimental data. Its core functionality comprises a bit-perfect emulation of the
electronic acquisition board, designated as Tell11, that performs data compression and hit reconstruction. The resulting hit (or cluster) bank is subsequently used by the HLT for track reconstruction. In order to
produce the emulated cluster bank non-zero suppressed (NZS) data are needed. These data are written
out as a part of the calibration stream with a small frequency of approximately 0.1 kHz2. Each stage of
the NZS data processing (such pedestal subtraction or common mode suppression) can be monitored
individually and appropriate key quantities can be extracted. The NZS data processing capability allows
to evaluate the noise and perform the full calibration procedure. In addition, the zero suppressed (ZS)
data that contains reconstructed hits can also be processed by the VETRA. This gives us access to such
quantities as cluster rates or energy deposits in silicon. The calibration data are taken continuously
during the normal operation of the LHCb detector. In order to process them efficiently a dedicated
automatic infrastructure, based on cron utility, has been created. By using a time-based job scheduler
we assert that all of the newly taken calibration data are processed and respective monitoring plots are
created. 1. Introduction The LHCb Vertex Locator (VELO) [1,2] is the most precise position sensitive detector currently
operating at LHC. VELO is a critical part of the LHCb High Level Trigger (HLT), thus, its optimal
performance is of the outmost importance for the whole LHCb spectrometer and has a direct impact on
the quality of the physics results produced by the experiment. The VELO group has designed and
implemented an innovative software platform which provides appropriate functionality to assert the best
possible running conditions for the vertex detector and to monitor its performance. In this note selected
features of this monitoring software are discussed. In the following section a description of the software 1 CHEP CHEP 1234567890
CHEP
IOP Publishing
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 1234567890
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 1234567890
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046 architecture is given. The core functionality of the monitoring part of the platform in described in Section
3. Both GUIs used to visualize and browse the monitored quantities are discussed in Sections 4 and 5
respectively. The paper is concluded by a short summary. architecture is given. The core functionality of the monitoring part of the platform in described in Section
3. Both GUIs used to visualize and browse the monitored quantities are discussed in Sections 4 and 5
respectively. The paper is concluded by a short summary. 2 The HLT output rate during the regular data taking amounts to approximately 12.5 kHz. 2.2. Lovell Lovell architecture diagram. The choice of a particular technological stack used for Lovell development was mainly driven by
features like stability, robustness and popularity (documentation). Using proven technologies decreased
significantly risks related to the design and implementation of such novel system as Lovell. Visualization is facilitated by PyQT and matplotlib. The former is used for the Lovell GUI design and
implementation whilst the latter is employed for graphic objects formatting and plotting. SQLite
management system was used to handle the data base needed for storing data that evolves with time and
bookkeeping. Since this is not a typical client-server engine it can be embedded in the application and
simplifies the overall architecture. Finally, for the simplified GIU implementation the Flask web micro
framework has been chosen. Figure 1. Lovell architecture diagram. The choice of a particular technological stack used for Lovell development was mainly driven by
features like stability, robustness and popularity (documentation). Using proven technologies decreased
significantly risks related to the design and implementation of such novel system as Lovell. Visualization is facilitated by PyQT and matplotlib. The former is used for the Lovell GUI design and
implementation whilst the latter is employed for graphic objects formatting and plotting. SQLite
management system was used to handle the data base needed for storing data that evolves with time and
bookkeeping. Since this is not a typical client-server engine it can be embedded in the application and
simplifies the overall architecture. Finally, for the simplified GIU implementation the Flask web micro
framework has been chosen. 3 Apart from the monitoring plots that are produced using the collision data it is possible to display the results
from, so called, special analyses such as IV characteristic scan that is performed to check the properties of the
VELO sensors. 2.2. Lovell The monitoring histograms produced by VETRA make the main input stream for the Lovell package. As mentioned in Section 2.1 these histograms are final and will not be processed in any way at this
stage. Lovell is implemented in Python which is particularly well suited for building involved systems
which must integrate diverse functionality such large data sets handling, building flexible graphical
interfaces, interaction with relational data bases or providing convenient tools for web application
design. A huge number of high quality modules available for Python allows a rapid development and
do not require writing large amounts of code. Also, it aids in testing and debugging cycle considerably
thanks to built-in utilities for agile programming. The architecture of Lovell is schematically presented in Figure 1. The main functionality can be
logically splitted into four parts. The first one is responsible for handling the input ROOT file and using
its content it can dynamically configure the main GUI. Since the input histograms are ROOT objects
they are difficult to handle and must be reformatted into matplotlib objects using tools from utilities
module of Lovell. The core functionality of Lovell is implemented in the analysis module (see Section
3 for more detailed description) that performs VELO data quality assessment using features obtained by
reducing the histogram data stream. These reduced data can also be used to create various trending plots
that are vital for tracking the condition of the VELO detector. The trending information as well as 2 1234567890
CHEP
IOP Publishing
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 CHEP CHEP 1234567890
CHEP
IOP Publishing
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 1234567890
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 bookkeeping is stored in a dedicated data base. Interaction with a user is handled via two specialized
graphical interfaces which can be called detailed and simplified respectively. The first one is optimized
for providing all available information obtained in the monitoring and calibration procedures3. This
feature is necessary for daily operation of the vertex detector and is the main tool for understanding
potential problems with the data quality. The second one is a web browser application that allows to
display selected histograms by a remote user without a necessity of connecting to the online processing
cluster. Figure 1. Lovell architecture diagram. Figure 1. 3. Analysis Framework The analysis framework is the central part of the VELO offline monitoring infrastructure. Its purpose is
to read in monitoring data, analyse their quality, and pass on the data themselves as well as the analysis
outcome to the two GUIs via a common interface. In addition, the analysis outcome is stored in a central
database, which serves as input for displaying trends of the various quantities. The monitoring data are read in from ROOT files containing one and two-dimensional histograms,
profiles, and graphs. Their content is translated into a python data format, which is provided to the GUIs
as a return value of a central data access method. The GUIs request this input by providing the path and
name of the object they want to display. j
y
p y
The graphics objects are then analysed in two ways. First, higher-level quantities, like mean or width
of a distribution, are assessed. The quantities to be extracted from these objects are configured in a 3 Apart from the monitoring plots that are produced using the collision data it is possible to display the results
from, so called, special analyses such as IV characteristic scan that is performed to check the properties of the
VELO sensors. 3 CHEP 1234567890
CHEP
IOP Publishing
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 1234567890
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 central configuration file. Second, these objects are compared to the corresponding ones in a reference
file. This comparison is quantified by means of statistical tests, the details of which are again defined in
a configuration file. Both the output of the individual analysis and that of the comparison are stored in
an analysis database as well as provided to the GUIs as additional information. central configuration file. Second, these objects are compared to the corresponding ones in a reference
file. This comparison is quantified by means of statistical tests, the details of which are again defined in
a configuration file. Both the output of the individual analysis and that of the comparison are stored in
an analysis database as well as provided to the GUIs as additional information. In addition to displaying the analysis information in the GUIs it is used as input for long-term trends,
which are obtained via database queries. 4.1. Pedestal subtracted data monitoring Pedestal subtraction is one of the most critical steps of the NZS data processing and hit reconstruction. If this procedure is not performed properly the output cluster bank may either be overflown with fake
hits (if the pedestals are underestimated) or the reconstruction efficiency may significantly drop (if the
pedestal values are too high). Pedestal subtraction is monitored for each sensor individually and both
one and two dimension plots are created. The former contains the mean values of the signal measured
in each channel after pedestal correction plotted against respective channel number whilst the latter one
saves the distribution of pedestal subtracted data for each readout channel. Also, a summary plot of the
mean values for the whole VELO is prepared which gives immediately information on the number of
channels where the correction is not effective. An example view regarding the pedestal correction
available in GUI is presented in Figure 2. 4. Graphical User Interface (GUI) and selected views A user interaction with Lovell is handled via two GUIs. In this section the one that can be run locally
on the online LHCb computing cluster is discussed whilst the web GUI is described in Section 5. The
main purpose of providing a GUI is to allow an operator to browse the results of respective monitoring
and analysis algorithms in an efficient and convenient way. These results are provided as histograms
representing a single monitored quantity, summary plots or trending plots. In this way any problem
flagged by central shifters can quickly be followed and understood. In the following text a selected
analyses that are presented by the local GUI are shortly discussed. 3. Analysis Framework These trends are available both for the quantities obtained from
individual plots, e.g. the average noise level as a function of time, and for the comparison output, e.g. the evolution of the matching quality with the reference for a particular monitoring output. These trends
are provided to the GUIs on request via a similar interface to the other graphics objects. Finally, in addition to the regular monitoring of offline data, the analysis framework also handles
data from special analyses such as current-voltage scans of the sensors that are carried out periodically. These are handled on an individual basis as their input data structure varies significantly depending on
the type of analysis, but the interface to the GUIs is very similar to that for offline monitoring data to
minimise the need to customisation in the GUIs. 4.4. IV scans Proton-proton collisions at LHC energies result in a very harsh hadronic environment which induces
significant radiation damage in silicon that leads to a drop in charge collection efficiency and larger
noise. Both effects impact severely the performance of the VELO and need to be carefully measured
and monitored. One of such analyses rely on measuring the leakage current as a function of reverse bias
voltage. The results can be used to assess the general condition of the sensors and tune the bias voltage
that is applied for each sensor during data taking. Lovell is instrumented with a proper module that can
access the IV scan data and display them in the GUI. 4.2. Tell1 processing parameters The quality of the VELO data is directly linked with its calibration which, in turn, is performed using
the NZS data stream taken at the end of each fill (when proton beams no longer collide). Such data
samples are often referred to as noise runs. The calibration procedure, implemented in VETRA, is then
executed and respective calibration constants are calculated. Since we require approximately one million
parameters to operate the VELO a task to monitor and analyse them is quite challenging. A dedicated
module for calibration data visualization is a part of Lovell and allows to create graphical objects
representing the most important calibration parameters such pedestals or clusterisation thresholds used
for hit reconstruction algorithm. It is also foreseen that analysis framework will be extended to add a
module for automatic calibration data assessment. This new functionality would check if the currently
used calibration is still valid and issue a request for evaluation of a new set of calibration constants if
necessary. 4 4 IOP Publishing CHEP 1234567890
CHEP
IOP Publishing
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 1234567890
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 1234567890
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046 Figure 2. The raw NZS (upper plot) and pedestal subtracted (lower plot) data measured in ADC units
on a selected VELO sensor for each readout channel (horizontal axis). Red triangles represent reference
data. Figure 2. The raw NZS (upper plot) and pedestal subtracted (lower plot) data measured in ADC units
on a selected VELO sensor for each readout channel (horizontal axis). Red triangles represent reference
data. 4.3. Clusters monitoring The main output data (ZS stream) produced by the vertex detector contains the cluster bank. Clusters
are objects representing the effects of the charged particles interactions with the VELO silicon sensors. They contain information on particle’s position (expressed in terms of strip number), deposited energy
and number of readout channels that contribute to a given cluster (cluster size). Detailed monitoring of
clusters is vital since they are used for track reconstruction by the LHCb high level trigger. Lovell offers
access to a diverse information pertaining to cluster reconstruction performance including among others
occupancy plots (evaluated per sensor and per readout channel), Landau distributions of energy deposits
and cluster multiplicity distributions. These plots are very important for daily operation of the VELO
during collision data taking and allow a quick and robust assessment of the detector performance. 5. Web GUI The Qt-based GUI discussed in the previous section is accessible to users working in the LHCb control
room, where the PCs are connected to the online network, and to external users via X11 forwarding over 5 CHEP 1234567890
CHEP
IOP Publishing
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/092046 1234567890
IOP Conf. Series: Journal of Physics: Conf. Series 898 (2017) 092046 1234567890
onf. Series: Journal of Physics: Conf. Series 898 (2017) 092046
doi :10.1088/1742-6596/898/9/0920 an SSH connection. The latter access pattern can be frustrating to use, due to latency over the Internet
causing lag in GUI interactions, or intermittent connections prematurely stopping the SSH session
entirely. To overcome these problems, a second GUI is made available over HTTP. It is accessible to
authenticated users on all systems, including mobile devices such as smartphones and tablets, and has
the added benefit of allowing users to share URLs to specific pages and plots, in case a detector problem
is found and requires discussion. an SSH connection. The latter access pattern can be frustrating to use, due to latency over the Internet
causing lag in GUI interactions, or intermittent connections prematurely stopping the SSH session
entirely. To overcome these problems, a second GUI is made available over HTTP. It is accessible to
authenticated users on all systems, including mobile devices such as smartphones and tablets, and has
the added benefit of allowing users to share URLs to specific pages and plots, in case a detector problem
is found and requires discussion. The architecture of the web GUI consists of two relatively well-separated components: a frontend,
comprised of webpages that the user (referred to here as the ‘client’) interacts with, and a backend,
which the frontend communicates with asynchronously via AJAX requests. The layout of each page in
the frontend, such as the section structure and what plots to display under what sections, is defined in a
GUI-agnostic configuration, such that a visual similarity is maintained with the Qt-based GUI. The backend presents a plot retrieval API through which any authenticated client can request plots. The frontend is then designed as ‘just another client’, rather than being tightly coupled to the workings
of the backend. This allows for the backend implementation to be changed without considering whether
the frontend is affected, given that the API isn't modified. 6. Summary y
A novel monitoring and analysis software platform, Lovell, employed by the LHCb VELO group for
daily operation of the vertex detector has been presented. Lovell constitute a central part of the
automatized infrastructure that is used to assert the proper calibration and highest possible data quality
produced by the detector. User interaction with the application is provided via two GUIs, one of which
is a web service that can be run outside of the LHCb online cluster. This is quite innovative approach
for the monitoring of the data collected by a high energy physics experiment. 5. Web GUI To reduce the workload on the web server process, plot retrieval and manipulation is offloaded to a
set of worker processes. When a client requests a plot from a specific data-taking period, the request is
pushed onto a queue which is monitored by the workers. An available worker pops a job off of the
queue, and is then responsible for loading the requested ROOT file, retrieving a specific plot from it,
and pushing a GUI-agnostic format of the plot onto an in-memory cache. (Both the queue and the result
cache are backed by Redis, with the worker queue logic handled by the rq Python package.) This
decoupling of the plot retrieval service from the web server increases the robustness of the latter, as a
failure in the plot retrieval only affects worker processes, which can easily be respawned. In addition,
such a decoupling allows for workers to be distributed across several computing nodes, and allows for
the number of workers to be simply scaled to cope with the demand on the web server. As the typical
monitoring page can contain five to ten plots, setting the number of workers to a similar magnitude
allows for all plots on a page to be retrieved at once, improving the perceived responsiveness of the
frontend. Acknowledgements We acknowledge support from CERN and LHCb and from the national agencies: FOM and NWO (The
Netherlands); MNiSW and NCN (Poland); STFC (United Kingdom). [2]
LHCb Velo Group, Performance of the LHCb Vetrex Locator, J. Instrum. 9 (2014) P09007
[3]
Szumlak T., VETRA: Offline analysis and monitoring software platform for the LHCb vertex
locator, J.Phys.Conf.Ser. 219 (2010) References [3]
Szumlak T., VETRA: Offline analysis and monitoring software platform for the LHCb vertex
locator, J.Phys.Conf.Ser. 219 (2010) 6 6
|
https://openalex.org/W4284969408
|
https://www.research-collection.ethz.ch/bitstream/20.500.11850/565794/2/syac048.pdf
|
English
| null |
Temperature-Dependent Evolutionary Speed Shapes the Evolution of Biodiversity Patterns Across Tetrapod Radiations
|
Systematic biology
| 2,022
|
cc-by
| 16,162
|
ETH Library A. SKEELS1,2,∗
, W. BACH1,2, O. HAGEN1,2,3
, W. JETZ4,5
AND L. PELLISSIER1,2,∗ We modeled four distinct evolutionary scenarios in which speciation-completion rates were dependent on
temperature (M1), life history (M2), temperature and life history (M3), or were independent of temperature and life-history
(M0). To assess the agreement between simulated and empirical data, we performed model selection by fitting supervised
machine learning models to multidimensional biodiversity patterns. We show that a model with temperature-dependent
rates of speciation (M1) consistently had the strongest support. In contrast to statistical inferences, which showed no
general relationships between temperature and speciation rates in tetrapods, we demonstrate how process-based modeling
can disentangle the causes behind empirical biodiversity patterns. Our study highlights how environmental energy has
played a fundamental role in the evolution of biodiversity over deep time. [Biogeography; diversification; machine learning;
macroevolution; molecular evolution; simulation.] across phylogenies or throughout geographic space, will
emerge from variation in evolutionary speed through
space and time (Fig. 1), and this could additionally
be influenced by major fluctuations in environmental
energy and temperature over the deep time scales
(Condamine et al. 2013; Meseguer and Condamine 2020). Therefore,aholisticintegrationofpatternsandprocesses
in the context of a dynamic Earth history may provide
mechanisticsupportfortheroleofenvironmentalenergy
in the evolution of life on Earth and the establishment of
biodiversity patterns. Environmental energy is a fundamental requirement
for the growth and persistence of organisms and often
a positive predictor of terrestrial biodiversity at broad
spatial scales (Currie 1991; Waide et al. 1999; Allen
et al. 2012). As such, the relationship between energy
and organismal biology, including metabolism and
growth rate, has been proposed as a key feature of
a unified theory of biodiversity (Brown 2004; Stegen
et al. 2009; Brown et al. 2014). However, the way in
which environmental energy shapes the evolution of
biodiversity is still debated. The evolutionary speed
hypothesis (ESH) (Rensch 1959; Rohde 1992) proposes
that different rates of biological processes, including
molecular and phenotypic evolution, result in different
speciation rates between environments with high- and
low kinetic energy (temperature; Allen et al. 2007), such
as between tropical and temperate biomes, leading to
an uneven distribution of biodiversity across the globe. There are multiple possible pathways predicted by the
ESH (Fig. A. SKEELS1,2,∗
, W. BACH1,2, O. HAGEN1,2,3
, W. JETZ4,5
AND L. PELLISSIER1,2,∗ 1): a direct temperature dependency of the
origin of biological variation through mutation (M1);
a direct life-history dependency of the rate in which
variation passes between generations through time, or
in other words the nucleotide generation time (Martin
and Palumbi 1993) (M2); and an interacting effect of
temperature and life history, such that rates are highest
in lineages with faster life histories occupying warmer
areas (M3). Faster rates in one of these pathways could
accelerate the formation of reproductive barriers or eco-
logical differentiation in diverging populations, leading
to speciation. It is expected that multiple biodiversity
patterns, including the distribution of speciation rates across phylogenies or throughout geographic space, will
emerge from variation in evolutionary speed through
space and time (Fig. 1), and this could additionally
be influenced by major fluctuations in environmental
energy and temperature over the deep time scales
(Condamine et al. 2013; Meseguer and Condamine 2020). across phylogenies or throughout geographic space, will
emerge from variation in evolutionary speed through
space and time (Fig. 1), and this could additionally
be influenced by major fluctuations in environmental
energy and temperature over the deep time scales
(Condamine et al. 2013; Meseguer and Condamine 2020). across phylogenies or throughout geographic space, will
emerge from variation in evolutionary speed through
space and time (Fig. 1), and this could additionally
be influenced by major fluctuations in environmental
energy and temperature over the deep time scales
(Condamine et al. 2013; Meseguer and Condamine 2020). Therefore,aholisticintegrationofpatternsandprocesses
in the context of a dynamic Earth history may provide
mechanisticsupportfortheroleofenvironmentalenergy
in the evolution of life on Earth and the establishment of
biodiversity patterns. g
Therefore,aholisticintegrationofpatternsandprocesses
in the context of a dynamic Earth history may provide
mechanisticsupportfortheroleofenvironmentalenergy
in the evolution of life on Earth and the establishment of
biodiversity patterns. y p
The kinetic energy of the environment could shape
evolutionary speed via different pathways, but it has
been difficult to find consistent support for the micro-
evolutionary processes underpinning the ESH. Environ-
mental energy can increase mutation rates from degen-
erative effects of UV radiation (reviewed in Hua and
Bromham 2017) or from increased oxidation from free
radicals associated with elevated metabolic rates (Martin
and Palumbi 1993; Gillooly et al. 2005; Gillooly and Allen
2007). If mutations are fixed within a population, then
energy will drive the rate at which populations diverge
and phenotypes change in the absence of gene flow. A. SKEELS1,2,∗
, W. BACH1,2, O. HAGEN1,2,3
, W. JETZ4,5
AND L. PELLISSIER1,2,∗ A. SKEELS1,2,∗
, W. BACH1,2, O. HAGEN1,2,3
, W. JETZ4,5
AND L. PELLISSIER1,2, 1Department of Environmental Systems Sciences, Landscape Ecology, Institute of Terrestrial Ecosystems, ETH Zürich, Zurich 8092, Switzerland; 2Swiss
Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf 8903, Switzerland; 3German Centre for Integrative Biodiversity Research
(iDiv) Halle-Jena-Leipzig, Leipzig 04103, Germany; 4Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520, USA, and
5Center for Biodiversity and Global Change, Yale University, New Haven, CT 06520, USA
∗Correspondence to be sent to: Ecosystems and Landscape Evolution Group, Department of Environmental Systems Sciences, Landscape Ecology, Institute of f
,
p
,
f
,
;
f
g
y
(iDiv) Halle-Jena-Leipzig, Leipzig 04103, Germany; 4Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520, USA, and
5Center for Biodiversity and Global Change, Yale University, New Haven, CT 06520, USA
∗Correspondence to be sent to: Ecosystems and Landscape Evolution Group, Department of Environmental Systems Sciences, Landscape Ecology, Institute of
Terrestrial Ecosystems, ETH Zürich, Zurich 8092, Switzerland. Email : alexander.skeels@gmail.com (AS); loic.pellissier@usys.ethz.ch (LP) Center for Biodiversity and Global Change, Yale University, New Haven, CT 06520, USA
∗Correspondence to be sent to: Ecosystems and Landscape Evolution Group, Department of Environmental Systems Sciences, Landscape Ecology, Institute of
Terrestrial Ecosystems, ETH Zürich, Zurich 8092, Switzerland. Email : alexander.skeels@gmail.com (AS); loic.pellissier@usys.ethz.ch (LP) f
y
g
y
∗Correspondence to be sent to: Ecosystems and Landscape Evolution Group, Department of Environmental Systems Scien
Terrestrial Ecosystems, ETH Zürich, Zurich 8092, Switzerland. Email : alexander.skeels@gmail.com (AS); loic.p ystems and Landscape Evolution Group, Department of Environmental Systems Sciences, Landscape Ecology, Institute of
H Zürich, Zurich 8092, Switzerland. Email : alexander.skeels@gmail.com (AS); loic.pellissier@usys.ethz.ch (LP) Received 8 October 2021; reviews returned 21 June 2022; accepted 5 July 2022
Associate Editor: Luke Harmon Received 8 October 2021; reviews returned 21 June 2022; accepted 5 July 2022
Associate Editor: Luke Harmon Abstract.—Biodiversity varies predictably with environmental energy around the globe, but the underlaying mechanisms
remain incompletely understood. The evolutionary speed hypothesis predicts that environmental kinetic energy shapes
variation in speciation rates through temperature- or life history-dependent rates of evolution. To test whether variation
in evolutionary speed can explain the relationship between energy and biodiversity in birds, mammals, amphibians, and
reptiles, we simulated diversification over 65 myr of geological and climatic change with a spatially explicit eco-evolutionary
simulation model. Author(s): This page was generated automatically upon download from the ETH Zurich Research Collection. For more information, please consult the Terms of use. Syst. Biol. ():–,
Syst. Biol. 0(0):1–16, 2022
© The Author(s) 2022. Published by Oxford University Press on behalf of the Society of Systematic Biologists. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/),
which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. https://doi.org/10.1093/sysbio/syac048
Advance Access Publication 9 July 2022
Syst. Biol. 72(2):341–356, 2023 Syst. Biol. ():–,
Syst. Biol. 0(0):1–16, 2022
© The Author(s) 2022. Published by Oxford University Press on behalf of the Society of Systematic Biologists. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/),
which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. https://doi.org/10.1093/sysbio/syac048
Ad
A
P bli
ti
9 J l 2022
Syst. Biol. 72(2):341–356, 2023 A. SKEELS1,2,∗
, W. BACH1,2, O. HAGEN1,2,3
, W. JETZ4,5
AND L. PELLISSIER1,2,∗ b) Predictions for variation in speciation rates with respect to temperature and body size based on alternative models
of the ESH. to macroevolutionary patterns of lineage diversifica-
tion and biodiversity gradients throughout geological
history. However, the relationship is complex and integ-
rates several interacting ecological and evolutionary
processes. Mutations that are fixed in a population
can drive speciation based on a Bateson–Dobzhansky–
Muller model of divergence in which reproductive isol-
ation results from incompatible genomes in genetically
differentiated populations (Dobzhansky 1982; Coyne
andOrr2004).Alternatively,highermutationratesmight
increase the standing genetic variation in a population
for natural selection to act upon, driving ecological spe-
ciation (Schluter and Conte 2009). Therefore, although
the specific mechanisms are debated, the core prediction
of the ESH is that faster rates of speciation occur in
high-temperature environments. Higher diversification
rates have been found in several clades occupying
lower latitudes and high-temperature environments
(Cardillo 1999), but there is also mounting evidence
that diversification rates are dynamic in both space and
time (Meseguer and Condamine 2020), reflecting major
changes in Earth’s climate and geology (Condamine
et al. 2013). In some cases, diversification rates are
decoupled or even negatively related to environmental
energy (Rabosky et al. 2015, 2018; Quintero and Jetz 2018;
Economo et al. 2019). There is also evidence that the
formation of reproductive isolation is not the limiting
factor in the formation of new species on deep time-
scales (Rabosky and Matute 2013). This has led to the
view that there is currently no unambiguous evidence (Bromham and Cardillo 2003; Orton et al. 2019) and in
some cases may be explained by covariation between
temperature and life-history traits such as longevity
(Hua et al. 2015). The underlying mechanism, such as
metabolic rates, also show inconsistent relationships
with rates of molecular evolution (Lanfear et al. 2007;
Santos 2012). These alternative results could be related
to the choice of active or resting metabolic rate as the
dependent variable (Gillman and Wright 2013), or may
instead be because enhanced DNA repair mechanisms
are selected for in harsh environments, compensating
for increased mutation rates (Ries et al. 2000; Lynch
2010; Hua et al. 2015; Svetec et al. 2016; Hua and
Bromham 2017). Temperature can further drive faster
growth rates and shorter generation times, which lead to
more cell divisions and recombination events, resulting
in a greater turnover of genetic material per unit of
time (Rohde 1992; Martin and Palumbi 1993; Dowle
et al. 2013). A. SKEELS1,2,∗
, W. BACH1,2, O. HAGEN1,2,3
, W. JETZ4,5
AND L. PELLISSIER1,2,∗ The
nature of the relationship between energy (or proxies
thereof) and rates of molecular evolution is mixed. A
positive relationship is supported across a broad range
of taxa, including fish (Wright et al. 2011), amphibians
(Wright et al. 2010), birds (Gillman et al. 2012), and
mammals (Gillman et al. 2009), lizards (Ivan et al. 2022),
turtles (Lourenço et al. 2013), angiosperms (Davies et al. 2004; Bromham et al. 2015), and foraminifera (Allen et al. 2006). However, these relationships are not universal 341
1 SYSTEMATIC BIOLOGY
SYSTEMATIC BIOLOGY 342
2 VOL. 72 Speciation rate
Speciation rate
Body size
Temperature
Time
Temperature
M3
M1M2
M0
M3
M1
Body size
M2
M3
Divergence
M3
M2
M0
M1
M0
M2
M3
M1
a)
b)
FIGURE 1. The evolutionary speed hypothesis (ESH) predicts alternative pathways for variation in the rate of population divergence and
speciation, driven by temperature (as a measure of environmental kinetic energy) or body size (as a proxy for life history speed). a) Alternative
models of population divergence under the ESH: M0—population divergence is a function of time from initial divergence; M1—population
divergence is a function of time and the average temperature across each population’s geographic range; M2—population divergence is a
function of time and the average body size of each population (as a proxy for life history); M3—population divergence is a function of time,
temperature, and body size. b) Predictions for variation in speciation rates with respect to temperature and body size based on alternative models
of the ESH. Speciation rate
Speciation rate
Body size
Temperature
M3
M2
M0
M1
M0
M2
M3
M1
b) Time
Temperature
M3
M1M2
M0
M3
M1
Body size
M2
M3
Divergence
a) b) Downloaded from https://academic.oup.com/sysbio/article/72/2/341/6637530 by ETH Zürich user on 21 June 2023 FIGURE 1. The evolutionary speed hypothesis (ESH) predicts alternative pathways for variation in the rate of population divergence and
speciation, driven by temperature (as a measure of environmental kinetic energy) or body size (as a proxy for life history speed). a) Alternative
models of population divergence under the ESH: M0—population divergence is a function of time from initial divergence; M1—population
divergence is a function of time and the average temperature across each population’s geographic range; M2—population divergence is a
function of time and the average body size of each population (as a proxy for life history); M3—population divergence is a function of time,
temperature, and body size. A. SKEELS1,2,∗
, W. BACH1,2, O. HAGEN1,2,3
, W. JETZ4,5
AND L. PELLISSIER1,2,∗ High rates of molecular evolution are
associated with fast life-history syndromes (e.g. small
body sizes, shorter generation times) in a number of
clades (Bromham et al. 1996; Bromham 2002; Qiu et al. 2014; Barrera-Redondo et al. 2018) and with high rates
of cell division (Lanfear et al. 2013) (but see [Weir and
Schluter 2008a]). If life-history, temperature, or both
together can drive rates of molecular evolution, then they
may directly influence rates of diversification (reviewed
in Dowle et al. 2013; Hua and Bromham 2017). The ESH links microevolutionary processes con-
trolling the origin and fixation of biological variation 3433 SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY 2023
2022 that the ESH drives biodiversity patterns such as the
latitudinal diversity gradient (Rabosky 2021). To gain
insight into the factors that shape variation in evol-
utionary speed, we must consider microevolutionary
drivers of diversification in the context of a dynamic
Earth history and alongside other potential drivers of
speciation. Although this is difficult to achieve with
empirical data on present day biodiversity, simulation
models that can integrate complementary biological,
ecological, and evolutionary mechanisms over deep-
time could offer a key tool to contrast alternative path-
ways and generate predictions regarding the formation
of biodiversity gradients (Descombes et al. 2018; Rangel
et al. 2018; Pontarp et al. 2019; Saupe et al. 2019; Hagen,
Flück et al. 2021). Temperature
Aridity
Model input
65 Ma
00 Ma
65 Ma
00 Ma
a) iii
ii
i
Body size
Temperature
Temperature
Aridity
Model input
Model
Model output
65 Ma
00 Ma
65 Ma
00 Ma
Empirical data
Spatial Patterns
Phylogenetic Patterns
Trait Patterns
M0
M3
M1
M2
Model selection
M1
M1 M1 M1
M1
Spatial Patterns
Phylogenetic Patterns
Trait Patterns
a)
b)
c)
e)
d) Temperature
Model input
a) Downloaded from https://academic.oup.com/sysbio/article/72/2/341/6637530 by ETH Zürich user on 21 June 2023 Downloaded from https://academic.oup.com/sysbio/article/72/2/341/6637530 by ETH Zürich user on 21 June 2023 iii
ii
i
Body size
Temperature
Model
b) Here,weassessedhowvariationinevolutionaryspeed
shapes emergent biodiversity patterns in tetrapods
(birds, mammals, amphibians, and reptiles) using a
simulation-based inference approach (Fig. 2), which
provides a new angle to investigate a challenging
hypothesis. We implemented alternative ESH models
(Fig.1)inaspatial,macroevolutionarysimulationengine
(Hagen, Flück et al. 2021), accounting for temporal and
spatial variation in environmental kinetic energy via
paleo-reconstructions of temperature over the Cenozoic
period (Hagen et al. 2019; Hagen, Flück et al. 2021). A. SKEELS1,2,∗
, W. BACH1,2, O. HAGEN1,2,3
, W. JETZ4,5
AND L. PELLISSIER1,2,∗ The simulations followed the diversification of lineages
on a gridded landscape based on paleoenvironmental
reconstructions of global temperature, aridity, and plate
tectonics (Fig. 2a), where variation in speciation rates
emerges from the speed in which populations diverge
in allopatry (Fig. 2b). We contrasted four models (Fig. 1)
where the rate of population divergence is driven by tem-
perature(M1),bodysize(asaproxyforlifehistoryspeed;
M2), and both temperature and body size together (M3),
as well as a null model in which divergence is unrelated
to body size or temperature (M0). We evaluated model
support in tetrapods using supervised machine learning
tools based on multiple spatial, phylogenetic, and trait-
based biodiversity metrics. These alternative models
provided a nested framework to test the interacting effect
of temperature and life history on divergence, which is
important for distinguishing between drivers of vari-
ation in evolutionary speed. For example, the metabolic
theory of ecology predicts support for a body-size-only
model of divergence (M2) for endotherms, whose body
temperature is independent of environmental temperat-
ure, but support for a temperature and body-size model
of divergence (M3) for ectotherms, who regulate body
temperature externally. Specifically, we asked: (i) are
there general, empirical correlations between environ-
mental temperature, species richness, body size, and
speciationratesintetrapodsthatmightsupporttheESH? (ii) How do biodiversity metrics differ between simu-
lated ESH models? (iii) Using simulation-based infer-
ence,whatistherelativesupportfortheESHintetrapods
based on multidimensional biodiversity patterns? Model output
c) Model output
c) Model output
Empirical data
Spatial Patterns
Phylogenetic Patterns
Trait Patterns
M0
M3
M1
M2
Model selection
M1
M1 M1 M1
M1
Spatial Patterns
Phylogenetic Patterns
Trait Patterns
c)
e)
d) Model output
Empirical data
Spatial Patterns
Phylogenetic Patterns
Trait Patterns
M0
M3
M1
M2
Model selection
M1
M1 M1 M1
M1
Spatial Patterns
Phylogenetic Patterns
Trait Patterns
c)
e)
d) Empirical data
d) Model selection
e) Model selection
e) FIGURE 2. Simulation-based inference framework for testing
the evolutionary speed hypothesis (ESH). Diversification is modeled
over macroevolutionary timescales on a dynamic gridded landscape
using the gen3sis simulation engine. a) Paleo-temperature and paleo-
aridity reconstructions at ∼170 kyr intervals from 65 Ma to the present
day are used as the domain for the simulation. b) Speciation begins
when populations of a species become geographically isolated (i). These populations diverge from one another through time. The rate
of divergence is a function of time (M0), time and temperature (M1),
time and body size (M2), or time, temperature, and body size (M3;
ii). Empirical Data and Biodiversity Summary Statistics The 54 biodiversity summary statistic metrics could be
broadly categorized into four classes: (i) species-specific
phylogenetic metric correlations, including correlations
between mean root distance (MRD) and body size;
(ii) spatial metric correlations, including correlations
between species richness, temperature, latitude, and
phylogenetic and phenotypic diversity across 220 km
× 220 km equal-area grid cells (see the Supplementary
Appendix SI for a discussion of spatial scale); (iii) trait
metric correlations and distributions, including proper-
ties of the frequency distribution of species’ temperature
niche or body size; (iv) phylogenetic tree size and
shape metrics, including clade size, tree imbalance, and
the distribution of node heights. For the order-level
analysis, phylogenetic metrics were calculated either
as the mean value across 50 trees sampled randomly
from the posterior distribution for each class, or as s
single value from the MCC tree, before subsequently
pruning species without matching spatial or trait data
for downstream analysis. We compared the impact of
these two methods on model selection (see below). For
the time-slice clade analysis, phylogenetic metrics were
only sampled on the MCC tree. y
We obtained matching data on the geographic dis-
tribution and phylogenetic position of extant species
of terrestrial vertebrates collected through the VertLife
project (vertlife.org) in association with Map of Life
(mol.org). Phylogenies were downloaded from VertLife
and follow (Jetz et al. 2012; Tonini et al. 2016; Jetz
and Pyron 2018; Upham et al. 2019; Colston et al. 2020). Distribution data for birds came from (Jetz et al. 2012) and for reptiles from the Global Assessment of
Reptile Distributions (Roll et al. 2017). For mammals and
amphibians, we modified distributions from the Interna-
tional Union for Conservation of Nature (International
Union for Conservation of Nature 2016) to match the
names of the respective phylogenies, and for squamate
reptiles, we matched names following (Skeels et al. 2019). We performed this step manually for crocodilia and
testudines. We aggregated spatial distributions into 220
km × 220 km equal-area grid cells to match the spatial
resolution of the simulated dataset. We obtained body-
size data from a variety of sources for birds (Wilman
et al. 2014), mammals (Wilman et al. 2014; Faurby et al. 2018; Cooke et al. 2019; Etard et al. 2020), amphibians
(Oliveira et al. 2017; Etard et al. 2020), and reptiles
(Meiri 2008, 2010, 2018; Feldman et al. 2016; Colston et al. 2020). Empirical Data and Biodiversity Summary Statistics We selected independent evolutionary radiations of
tetrapods to test the ESH at the level of taxonomic
order for birds, mammals, and amphibians, as well
as for testudines and crocodilian reptiles. We divided
squamate reptiles, the most diverse terrestrial vertebrate
order, intosixinfraorders(hereafterreferredtoasorders)
as this group was significantly more diverse than other
orders and a taxonomic classification above the family-
level was available for this group (Meiri 2018). We
selected taxonomic orders as the unit of comparison
because the ages of these clades are mostly closely
distributed around 65 Ma allowing for a fair comparison
with simulated data (Supplementary Fig. S1) as well as
being readily biologically and ecologically interpretable. Some clades, however, are significantly older than 65
Ma (Supplementary Fig. S1). To test whether our results
might be biased by the variance in clade age, we dissect
the maximum clade credibility (MCC) phylogenetic tree
for each taxonomic class at 65 Ma and repeat the
model selection procedure (see below) on all subtrees
(henceforth referred to as time-slice clades), ensuring
clade age was consistent in simulated and empirical
data. We found the results to be qualitatively similar
for the time-slice clade analyses and we present these
in Supplementary Appendix S4, whereas here focusing
on the order-level analysis. )
There are many ways to summarize biodiversity
patterns, and we selected 54 different summary statistics
that capture phylogenetic, spatial, and functional trait-
based dimensions of biodiversity and can be assigned
as a single numeric value to each clade (Supplementary
Table S1). We focused on body size as a phenotypic
trait that is ecologically significant and covaries with
life history across taxa (Promislow et al. 1992). We also
acknowledge that the relationship between life-history
traits (such as generation time) and body size is variable
across taxa (Promislow et al. 1992); however, it remains
one of the best available proxies for a wide range of
species across vertebrate taxa. Body size might drive
variation in diversification rates independently of a
generation time effect (e.g., via metabolic rates [Gillooly
et al. 2005]). As such, support for body-size dependent
model would be suggestive of an effect of generation
time. Additionally, we estimated species’ temperature
nichesusingthemeanvalueofmeanannualtemperature
(CHELSA; Karger et al. 2017) across all 220 km ×
220 km grid cells within a species’ geographic range. MATERIALS AND METHODS MATERIALS AND METHODS because summary statistics calculated on small samples
may show spurious patterns. The retained orders varied
in their diversity between 20 and 5966 species (mean
=604). Empirical Data and Biodiversity Summary Statistics A. SKEELS1,2,∗
, W. BACH1,2, O. HAGEN1,2,3
, W. JETZ4,5
AND L. PELLISSIER1,2,∗ Diverging populations become distinct species after a threshold of
differentiation is reached (iii). c) Biodiversity patterns emerge from the
distribution of species, phylogenetic relationships, and the evolution
of traits and are summarized using different summary statistics. d)
Empirical biodiversity patterns in tetrapods are summarized using
the same set of summary statistics as for the simulated data based on
species distributions, phylogenetic relationships, and functional traits. e) Supervised machine learning classification algorithms are trained
on the simulated summary statistics from four different population
divergence models (M0–M3) and are used to perform model selection
on the empirical summary statistics. 344
4 SYSTEMATIC BIOLOGY
SYSTEMATIC BIOLOGY VOL. 72 VOL. 72 Simulation Model We implemented four alternative models of diver-
sification using the spatially explicit general engine
for eco-evolutionary simulations, gen3sis, version 1.3
(Hagen, Flück et al. 2021). The simulations follow the
diversification of a clade from a single ancestral species
at the beginning of the Cenozoic (65 Ma; Supplementary
Fig. S2). The simulations track populations as they
disperse and diversify throughout 65 myr of reconstruc-
ted temperature, aridity, plate tectonic, and geomor-
phological changes across a gridded global landscape
at 220 km × 220 km resolution (Hagen et al. 2019). Paleoenvironmental reconstructions allow us to account
for dynamic changes and fluctuations of temperature
over the Cenozoic, expressed via temperature, in driving
variation in evolutionary speed under the different
diversification models. Unlike previous simulation mod-
els testing the ESH (e.g., Hurlbert and Stegen 2014a,b),
this model inherently incorporates evolutionary inertia
of species environmental niches and geographical dis-
tributions in two-dimensional space, where speciation
and extinction are emergent properties rather than
determined probabilistically according to a birth–death
model. As such, the ESH is modeled alongside other
factors which may have been instrumental in shaping
contemporary biodiversity patterns, such as climate
change and stability (Dynesius and Jansson 2000a), or
changes in the available area of suitable habitat through
time (Jetz and Fine 2012). Biodiversity patterns emerge
from simulated phylogenetic trees, spatial distributions
of species, and trait distributions. Nij =K∗exp(−(Ti−Tj/ω)2),
(1) (1) where ω is a parameter that determines the strength of
environmental filtering, with small values leading to a
sharper decline in abundance as the species temperature
niche optimum (Ti) becomes more different from the
temperature of the site (Tj). Nij equals K in the absence
of competitors if population i is perfectly adapted to the
site. The carrying capacity for each site (K) is entirely
independent of temperature but decreases exponentially
with the aridity index in each site (Aj), according to the
function: where ω is a parameter that determines the strength of
environmental filtering, with small values leading to a
sharper decline in abundance as the species temperature
niche optimum (Ti) becomes more different from the
temperature of the site (Tj). Nij equals K in the absence
of competitors if population i is perfectly adapted to the
site. Empirical Data and Biodiversity Summary Statistics Both temperature and aridity
values were standardized between 0 and 1 in the
simulation model. At each time step (∼170 kyr), each population can
disperse into surrounding sites from a dispersal kernel
drawn from a Weibull distribution with a fixed shape
parameter ( =2.5) and variable scale parameter ( ;
Supplementary Fig. S3). The size (N) of population
i in site j is fixed and constant at each time step
and determined by (i) environmental suitability based
on the species’ thermal niche, (ii) carrying capacity
based on aridity, and (iii) the presence of competitors. Environmental suitability is a Gaussian function of the
thermal niche, which declines with increasing distance
between the temperature value in the site (Tj) and
the population’s temperature optimum (Ti), following
(McPeek 2007, 2008) (Supplementary Fig. S4): Empirical Data and Biodiversity Summary Statistics We
transformed these Spearman correlation coefficients to
Z-scores and estimated 95% confidence intervals using
Fischer transformations in the R package DescTools
(Signorell 2021). To see if directional trends existed in the
correlations, we estimated the size of the average effect
for each correlation separately using random-effects
models and restricted maximum-likelihood estimation
in the R package metafor (Viechtbauer 2010). We repeated
this analysis using coefficients from phylogenetic or
spatial generalized least squares models which account
for the non-independence of observations based on
shared ancestry and spatial proximity, respectfully, and
we found similar results (Supplementary Appendix S4). grid-cells; (ii) correlation between species richness and
temperature across grid-cells; (iii) correlation between
speciation rate and body size across species; and (iv)
correlation between speciation rate and temperature
across species. We estimated speciation rates using the
DR statistic (Redding and Mooers 2006; Jetz et al. 2012),
which has been shown to be a good approximation of
recent speciation rates (Title and Rabosky 2019). We
transformed these Spearman correlation coefficients to
Z-scores and estimated 95% confidence intervals using
Fischer transformations in the R package DescTools
(Signorell 2021). To see if directional trends existed in the
correlations, we estimated the size of the average effect
for each correlation separately using random-effects
models and restricted maximum-likelihood estimation
in the R package metafor (Viechtbauer 2010). We repeated
this analysis using coefficients from phylogenetic or
spatial generalized least squares models which account
for the non-independence of observations based on
shared ancestry and spatial proximity, respectfully, and
we found similar results (Supplementary Appendix S4). temperature value based on present-day averages for
each belt. This temperature reconstruction approximates
thechangeinthesteepnessofthelatitudinaltemperature
gradient over deep-time (Scotese et al. 2021). To account
for global fluctuations in temperature, the temperature
values assigned to Koeppen climate belts were adjusted
according to global average temperature curves based
on oxygen isotope data (Scotese et al. 2021). Finally,
to account for local variation in temperature due to
topography, we applied a lapse rate to temperature
values at a rate of 6.5◦per 1 km of altitude based on
elevation from a Paleo-digital elevation model sampled
at 1 myr intervals, which includes plate tectonic move-
ments (Scotese and Wright 2018). The final temperature
values at 1 myr intervals and 1-degree spatial resolution
were linearly interpolated to 170 kyr intervals and 220
km × 220 km equal area resolution using a Behrmann
projection. Aridity values were taken as the sub-tropical
arid Koeppen climate belt. Empirical Data and Biodiversity Summary Statistics This dataset comprised of matching phylogenetic,
spatial, and body size data for 32,024 species including,
9991 species of birds, 6677 amphibians, 9859 reptiles,
and 5497 mammals. We then selected all orders (n=48),
and time-slice clades (n=164) with more than 20 species
for further analyses. We use 20 species as a threshold y
p
The ESH is associated with well-constrained predic-
tions about the distribution of biodiversity in space
and variation in diversification rates across lineages
(Fig. 1), and before exploring the support for the ESH
using the simulation-based approach, we asked to what
degree these predictions were supported in tetrapods
using a traditional correlative approach. We used meta-
analytical tools to test for general patterns in four
of these key summary statistics based on Spearman
correlations across tetrapod taxa: (i) coefficient of cor-
relation between species richness and latitude across SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY 3455 2023
2022 temperature value based on present-day averages for
each belt. This temperature reconstruction approximates
thechangeinthesteepnessofthelatitudinaltemperature
gradient over deep-time (Scotese et al. 2021). To account
for global fluctuations in temperature, the temperature
values assigned to Koeppen climate belts were adjusted
according to global average temperature curves based
on oxygen isotope data (Scotese et al. 2021). Finally,
to account for local variation in temperature due to
topography, we applied a lapse rate to temperature
values at a rate of 6.5◦per 1 km of altitude based on
elevation from a Paleo-digital elevation model sampled
at 1 myr intervals, which includes plate tectonic move-
ments (Scotese and Wright 2018). The final temperature
values at 1 myr intervals and 1-degree spatial resolution
were linearly interpolated to 170 kyr intervals and 220
km × 220 km equal area resolution using a Behrmann
projection. Aridity values were taken as the sub-tropical
arid Koeppen climate belt. Both temperature and aridity
values were standardized between 0 and 1 in the
simulation model. grid-cells; (ii) correlation between species richness and
temperature across grid-cells; (iii) correlation between
speciation rate and body size across species; and (iv)
correlation between speciation rate and temperature
across species. We estimated speciation rates using the
DR statistic (Redding and Mooers 2006; Jetz et al. 2012),
which has been shown to be a good approximation of
recent speciation rates (Title and Rabosky 2019). Simulation Model (3) (3) Local extinction occurs deterministically if ˆNij =0 or
stochastically as a sigmoidal function of ˆNij: ,
1−ˆB and ˆT (hereafter ˆB ˆT), scaled exponentially with
the parameter , such that genetic divergence is faster
in small-bodied populations in warmer regions and
decreases exponentially as species increase in body size
and occupy cooler sites (Supplementary Fig. S7): 1/(1+exp(− d∗( t−ˆNij))),
(4) (4) where t is the population size threshold below which
extirpation in site j becomes more likely and d is the rate
of decay of the function (Supplementary Fig. S6). t and
d parameters were fixed across simulations. Extinction
of a species occurs when it no longer occupies any sites. gi,k =((ˆB ˆTI + ˆB ˆTk)/2). (7) (7) We ran the simulation model 500 times under each
of the four scenarios, varying six key parameters: the
divergence threshold [S, parameter range = (2, 10)], the
rate scaling factor for the rate of population divergence
under M1–M3 [, (2, 5)], the strength of environmental
filtering for the temperature niche trait [ω, (0.01, 0.035)],
the rate of body-size evolution under Brownian motion
[B, (0.001, 0.02)], the rate of temperature niche evolution
[T, (0.001, 0.015)], and the dispersal kernel [, (330,
880)]. These parameter ranges were determined via
preliminary examination of the simulation model to
broadly cover a range of conditions while consistently
generating clades of comparable size to the empirical
data (∼20–6000 species; Supplementary Fig. S9). The
model is computationally intensive, which restricts the
number of replicates possible. To accommodate this
limitation, we used a quasi-random sampling technique
to select parameter combinations that evenly cover
the six-dimensional parameter space (approximating a
uniform distribution for each parameter) using Sobol
sequences (Burhenne et al. 2011) and assessed the
subsequent parameter sensitivity. It has been shown that
strategies that sample parameters broadly and evenly
across multidimensional parameter space are efficient
for exploring stochastic simulation models (Prowse et al. 2016). Evolution of the temperature niche trait (Ti) and body
size (Bi) for each independently evolving population
approximatesaboundedBrownianmotionmodeloftrait
evolution. The traits drift randomly though time but are
bound between values of 0 and 1. The value of the trait
at increasing time intervals of t is equal to the value
of the trait at time t plus a value drawn from a normal
distributionwithameanof0andstandarddeviationof. We model separate rates for temperature evolution (T)
and body size evolution (B; Supplementary Fig. S7). Simulation Model y
(
pp
y
g
)
Speciation is based on an allopatric model of speci-
ation, and populations of a species that become geo-
graphically isolated from each other diverge genetically
at each time step. Under the null model (M0), where
population divergence is independent of temperature
and body size, the amount of genetic divergence (g) at
each time step is drawn from a uniform distribution (0.01,
1). Diverging populations become distinct species once
genetic divergence has crossed threshold S (2, 10). We
model the effect of migration on genetic differentiation
as, if populations have secondary contact (i.e., they
return to within-dispersal distance of one another), they
coalesce toward genetic homogeneity at a rate of 1
per time step. We additionally model three alternative
scenarios in which rates of population divergence
are temperature-dependent (M1), body-size dependent
(M2), or temperature and body-size dependent (M3). Under M1, the genetic divergence of populations i and k
(gi,k) is a function of the sum of the average temperatures
( ˆT) experienced by diverging populations i and k
across all sites within their geographic range, scaled
exponentially with the parameter (Supplementary
Fig. S8): Model Validation and Sensitivity Analysis We estimated the same 54 biodiversity summary
statistics on the simulated data as calculated for the
empirical data (Supplementary Table S1). We then
assessed the validity of the model by comparing the
univariate distributions of the simulated and empirical
summary statistics (Supplementary Fig. S10), as well
as the overlap in multivariate space using principal
component analysis (PCA; Supplementary Fig. S11). We investigated model behavior and the relationships
betweenmodelparametersandsummarystatisticsusing
global sensitivity analysis, following the procedure of
(Prowse et al. 2016) (Supplementary Figs. S12–S14), as gi,k =(( ˆTI + ˆTk)/2). (5) (5) Simulation Model The carrying capacity for each site (K) is entirely
independent of temperature but decreases exponentially
with the aridity index in each site (Aj), according to the
function: K =Kc∗exp(−1∗Aj),
(2) (2) where Kc is a constant (30,000) determining the max-
imum carrying capacity in the grid cell (Supplementary
Fig. S5). The decision to limit the carrying capacity
of sites by aridity was based on the assumption that
water availability is one of the major limiting factors for
primary productivity and population size is a function of
productivity based on resource availability (Waide et al. 1999; Gillman and Wright 2006). We model a zero-sum
game where sites have finite resources available, which
places an ecological limit on the maximum number of p
Following Hagen et al. (2019); Hagen, Flück et al. (2021), and Scotese et al. (2021), paleoenvironmental tem-
perature was derived from reconstructions of Koeppen
climatic belts at 5 myr intervals during the Cenozoic
(Scotese et al. 2021). These belts were assigned a SYSTEMATIC BIOLOGY
SYSTEMATIC BIOLOGY 346
6 VOL. 72 VOL. 72 decline toward 0 as species inhabit cooler grid cells. Under M2, gi,k is a function of the sum of the average
standardized body sizes (ˆB) of diverging populations i
and k, scaled exponentially with the parameter (2, 5)
(Supplementary Fig. S7): individuals in a site across populations of all species
present (Nj). In saturated communities (Nj ≥K), when
new species colonize or become locally extinct from a
site, abundances of all species are reapportioned accord-
ing to the environmental suitability of each species, such
that well-adapted species obtain a higher abundance
than poorly adapted species, following (Hurlbert and
Stegen 2014c): gi,k =((1−ˆBI +1−ˆBk)/2). (6) (6) Here, genetic divergence exponentially approaches
a value of 1 as body size decreases, at a rate of . Finally, under M3, gi,k is a function of the average of
1−ˆB and ˆT (hereafter ˆB ˆT), scaled exponentially with
the parameter , such that genetic divergence is faster
in small-bodied populations in warmer regions and
decreases exponentially as species increase in body size
and occupy cooler sites (Supplementary Fig. S7): Here, genetic divergence exponentially approaches
a value of 1 as body size decreases, at a rate of . Finally, under M3, gi,k is a function of the average of ˆNij =Nij∗min(Nj,K)/Nj. (5) As temperature values are standardized between 0
and 1, the maximum value of g at each time step is
equal to 1, and determines the rate of exponential SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY 3477 2023
2022 well as visualizing the relationships between model
parameters and summary statistics in multivariate space
using PCA (Supplementary Figs. S11 and S15). We
removed seven summary statistics which were not
well captured by the simulation model, as well as
23 variables that were highly collinear (Pearson’s r>
0.90; Supplementary Fig. S16), from the dataset, leading
to 26 summary statistics for downstream analyses. For a detailed description of the simulation model,
experimental design, model validation, and sensitivity
analysis, please see the Supplementary Methods in
Appendix S3. datasets (Supplementary Fig. S9), the distribution was
different, with empirical data being far more right
skewed toward smaller sizes (simulated skewness =
0.23, empirical skewness =4.45; Supplementary Fig. S9). To investigate whether this difference in clade size
distributions influenced the results, we repeated the
model selection procedure by training the machine
learning models on a subset of the simulated data
that produced clades with fewer than 1000 species and
repeated the predictions. Finally, to compare the impact
of the method of phylogenetic metric calculations, we
repeated the model selection procedure using phylo-
genetic metrics calculated on the MCC tree, or the
mean values from across a sample of 50 trees from
the posterior distribution. In all these analyses, the
results were qualitatively similar and are presented in
the Supplementary Appendix (Supplementary Table S3
and Fig. S18). Empirical Biodiversity Patterns Meta-analysis of Spearman correlation coefficients
between temperature and species richness and between
latitude and species richness, as measured across 220 km
× 220 km grid cells, showed that general effects were
directional, with temperature showing a positive net
effect on species richness ( =0.169±0.046,Z=3.688,P=
0.0002) and latitude showing a negative net effect
on species richness ( =−0.230±0.0581,Z=−3.951,P<
0.001; Fig. 3d). Meta-analysis of trends in the relation-
ship between species-specific estimates of speciation
rates, and body size and between speciation rates
(DR) and temperature, showed that, unlike the spatial
correlations, these species-level correlations did not
show any directional trends among tetrapods (temperat-
ure ∼DR, =−0.009±0.008,Z=−1.089,P=0.28; body
size ∼DR, =0.0003±0.0003,Z=0.972,P=0.331). These
results were also supported when considering the non-
independence of observations using spatial or phylogen-
etic generalized least squares models (Supplementary
Appendix S4). Model Discrimination After characterizing how biodiversity patterns are
generated by the model parameters and checking the
validity of the model in capturing realistic biodiversity
patterns, we asked whether biodiversity patterns differ
between the population divergence models. We sub-
set the complete simulation dataset to include only
those simulations whose parameters led to complete
simulations under all four models of population diver-
gence (n=1384) to ensure equal sample sizes between
model classes. We used supervised machine learning
model classification tools with 10-fold cross-validation
repeated 10 times on a two-thirds training subset of
the simulated data (n=917). We then estimated reclas-
sification accuracy based on model predictions on the
withheld one-third test dataset (n=467). To investigate
the robustness of the results to different machine
learning algorithms, we used the R package Caret to
repeat this procedure for seven different classification
algorithms: linear discriminant analysis, three decision
tree algorithms (recursive partitioning and regression
trees, random forest, and a gradient-boosting machine
algorithm), naïve Bayes, support-vector machines, and
neural networks. We assessed model reclassification
accuracy (Supplementary Table S2) and ranked the
different classification algorithms using global accuracy
and Cohen’s metrics (Supplementary Fig. S17). We
investigated which biodiversity summary statistics were
most important in separating the models of population
divergence by looking at the relative contribution of each
summary statistic using variable importance factors. Model Selection Downloaded from https://academic.oup.com/sysbio/article/72/2/341/6637530 by ETH Zürich user on 21 June 2023 a) Crocodylia
Tinamiformes
Galliformes
Anseriformes
Caprimulgiformes
Apodiformes
Charadriiformes
Strigiformes
Accipitriformes
Trogoniformes
Bucerotiformes
Coraciiformes
Piciformes
Falconiformes
Psittaciformes
Passeriformes
Columbiformes
Otidiformes
Cuculiformes
Gruiformes
Procellariiformes
Pelecaniformes
Suliformes
Musophagiformes
Testudines
Dibamia
Gekkota
Scincoidea
Lacertoidea
Anguimorpha
Iguania
Serpentes
Eulipotyphla
Chiroptera
Carnivora
Cetartiodactyla
Primates
Scandentia
Lagomorpha
Rodentia
Cingulata
Afrosoricida
Didelphimorphia
Dasyuromorphia
Diprotodontia
Anura
Caudata
Gymnophiona
1
2
3
4
300
200
100
0
−0.6
−0.3
0.0
0.3
0.6
−0.4
0.0
0.4
Spearman correlation
coefficient (ρ)
Model
M0
M1
M2
M3
0.8
−0.8
+
-
+
-
a)
b)
c)
d)
e)
E 3. Empirical support based on 26 summary statistics for population divergence models (M0–M3) and the distribution of four
mary statistics in tetrapod orders. a) Phylogenetic relationships of 48 orders of birds, mammals, amphibians, and reptiles (squamate
divided into six infraorders) with b) -weighted averaged posterior support from seven different model classification algorithms for
ulation divergence model and c) the best supported population divergence model shown in colored circles. Circle graph beneath this
hows the proportion of clades with support for each model. d) Spearman correlation coefficients ( ) between species richness and (1)
and (2) temperature, measured at 220 km × 220 km grid cells. Circle graphs show the proportion of positive and negative correlations. man correlation coefficients ( ) between speciation rate (measured using the DR statistic) and (3) body size and (4) and temperature
d at species-level. Circle graphs show the proportion of positive and negative correlations. Downloaded from https://academic.oup.com/sysbio/article/72/2/341/6637530 by ETH Zürich user on 21 June 2023 Crocodylia
Tinamiformes
Galliformes
Anseriformes
Caprimulgiformes
Apodiformes
Charadriiformes
Strigiformes
Accipitriformes
Trogoniformes
Bucerotiformes
Coraciiformes
Piciformes
Falconiformes
Psittaciformes
Passeriformes
Columbiformes
Otidiformes
Cuculiformes
Gruiformes
Procellariiformes
Pelecaniformes
Suliformes
Musophagiformes
Testudines
Dibamia
Gekkota
Scincoidea
Lacertoidea
Anguimorpha
Iguania
Serpentes
Eulipotyphla
Chiroptera
Carnivora
Cetartiodactyla
Primates
Scandentia
Lagomorpha
Rodentia
Cingulata
Afrosoricida
Didelphimorphia
Dasyuromorphia
Diprotodontia
Anura
Caudata
Gymnophiona
300
200
100
0
−0.6
−0.3
0.0
0.3
0.6
−0.4
0.0
0.4
Spearman correlation
coefficient (ρ)
Model
M0
M1
M2
M3
0.8
−0.8
+
-
+
-
a) Downloaded from https://academic.oup.com/sysbio/article/72/2/341/6637530 by ETH Zürich user on 21 June 2023 FIGURE 3. Empirical support based on 26 summary statistics for population divergence models (M0–M3) and the distribution of four
key summary statistics in tetrapod orders. Model Selection Biodiversity
patterns
in
the
simulations
varied
between population divergence models, leading to high
discrimination ability of machine learning classification
algorithms. Using 10-fold cross-validation repeated 10
times with 7 different model classification algorithms,
we found a high proportion of correctly identified popu-
lation divergence models, with classification considered
in moderate (McHugh 2012) to substantial (Cohen 1960)
agreement based on Cohen’s (global accuracy [0.66,
0.78]; Cohen’s [0.54, 0.71]). We found that different
model classification algorithms varied in their per-
formance, with models allowing complex relationships As a final step, we fitted the machine learning
classification models to the empirical data, estimated
the relative support for each population divergence
model using all seven machine learning algorithms,
and weighted these estimates using Cohen’s to obtain
model-averaged support for each population divergence
model in each clade. To interrogate the role of clade
age in influencing the model selection results, we
repeated the model selection procedure on all time-
slice clades. Furthermore, although the range of clade
sizes was similar between simulated and empirical SYSTEMATIC BIOLOGY
SYSTEMATIC BIOLOGY 348
8 VOL. 72 Crocodylia
Tinamiformes
Galliformes
Anseriformes
Caprimulgiformes
Apodiformes
Charadriiformes
Strigiformes
Accipitriformes
Trogoniformes
Bucerotiformes
Coraciiformes
Piciformes
Falconiformes
Psittaciformes
Passeriformes
Columbiformes
Otidiformes
Cuculiformes
Gruiformes
Procellariiformes
Pelecaniformes
Suliformes
Musophagiformes
Testudines
Dibamia
Gekkota
Scincoidea
Lacertoidea
Anguimorpha
Iguania
Serpentes
Eulipotyphla
Chiroptera
Carnivora
Cetartiodactyla
Primates
Scandentia
Lagomorpha
Rodentia
Cingulata
Afrosoricida
Didelphimorphia
Dasyuromorphia
Diprotodontia
Anura
Caudata
Gymnophiona
300
200
100
0
−0.6
−0.3
0.0
0.3
0.6
−0.4
0.0
0.4
Spearman correlation
coefficient (ρ)
Model
M0
M1
M2
M3
0.8
−0.8
+
-
+
-
a)
Empirical support based on 26 summary statisti b) c) s
1
2
3
4
b)
c)
d)
e)
tistics for population divergence models (M0–M3) and the distribution of four
ationships of 48 orders of birds, mammals, amphibians, and reptiles (squamate
aged posterior support from seven different model classification algorithms for
population divergence model shown in colored circles. Circle graph beneath this
model. d) Spearman correlation coefficients ( ) between species richness and (1)
id cells. Circle graphs show the proportion of positive and negative correlations. te (measured using the DR statistic) and (3) body size and (4) and temperature
of positive and negative correlations. DISCUSSION Temperature is thought to play an integral role in
shaping rates of speciation by driving rates of molecu-
lar evolution and subsequent speciation in diverging
populations (Rohde 1992). Despite a strong theoretical
underpinning (Allen et al. 2002; Brown 2004), a positive
link between environmental energy, in the form of
temperature (or otherwise), and rates of diversification
has rarely been observed in large comparative datasets
(Jetz et al. 2012; Rabosky et al. 2018). As such, current
evidence favors alternative mechanisms in shaping
biodiversity patterns, such as evolutionary time (Marin
and Hedges 2016; Miller et al. 2018), ecological limits
(Rabosky and Hurlbert 2015) (but see Harmon and
Harrison 2015), or an effect of geographic area over
time (Fine and Ree 2006; Jetz and Fine 2012). Yet,
tests of the ESH typically treat temperature as a static
feature of the present-day, rather than considering how
dynamic changes in temperature over deep-time scales
may influence diversification dynamics. Furthermore,
highly dimensional biodiversity patterns, integrating
traits, spatial distributions, and phylogeny are rarely
used to draw inferences on macroevolutionary patterns. Contrary to findings from earlier studies, by combining
spatially explicit simulation models that incorporate
historical fluctuations in temperature and simulation-
based inference tools, we found common support for a
diversification model including temperature-dependent
divergence across tetrapods. This support was estimated
from a suite of commonly used biodiversity summary
statistics, reflecting spatial, trait, and phylogenetic pat-
terns, highlighting that a diverse array of summary
statistics is needed to diagnose models of population
divergence from commonly used biodiversity data. Model Selection a) Phylogenetic relationships of 48 orders of birds, mammals, amphibians, and reptiles (squamate
reptiles divided into six infraorders) with b) -weighted averaged posterior support from seven different model classification algorithms for
each population divergence model and c) the best supported population divergence model shown in colored circles. Circle graph beneath this
column shows the proportion of clades with support for each model. d) Spearman correlation coefficients ( ) between species richness and (1)
latitude and (2) temperature, measured at 220 km × 220 km grid cells. Circle graphs show the proportion of positive and negative correlations. e) Spearman correlation coefficients ( ) between speciation rate (measured using the DR statistic) and (3) body size and (4) and temperature
measured at species-level. Circle graphs show the proportion of positive and negative correlations. SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY 3499 2023
2022 between variables (e.g., neural networks, gradient boost-
ing models, and support vector machines) having higher
global accuracy (Supplementary Fig. S17). We also found
that for all algorithms, there was variation in prediction
accuracy across model classes (Supplementary Table S2),
with M3, which combines the temperature-dependent
divergence of M1 and body-size-dependent divergence
of M2, having lower rates of true positives (sensitivity)
and true negatives (specificity; Supplementary Table S2). We found that summary statistics contributing most to
the discrimination ability, based on variable importance
factors from each classification algorithm weighted by
the value from each algorithm, represented several
different categories of summary statistic (Fig. 4a). For
example, the two summary statistics with the highest
variable importance scores were a correlation between
body size and the equal splits measure of evolutionary
distinctiveness (a proxy for speciation rate), and a correl-
ation between geographic range size and temperature,
which represent phylogenetic metric correlations and
trait metric correlations, respectively. In contrast, some
biodiversity summary statistics only weakly contrib-
ute to model discrimination, including a correlation
coefficient between species richness and temperature. A negative correlation between absolute latitude and
species richness and a positive relationship between
temperature and species richness emerged with all
models (Fig. 4b). attributed to a single model (e.g.„ M1 in the hornbills and
allies, Bucerotiformes; Fig. 3b), whereas in other clades,
support was more evenly distributed across population-
divergence models (e.g., support was split between M2
and M3 in the nightjars and allies, Caprimulgiformes;
Fig. 3b). Model Selection mean summary statistic
M0
M1
M2
M3
0.0
0.7
0 0
0.0
0
0.0
0.7
0 0
0.0
0.0
0
0.0
1.0
0 0
0.0
0
0.0
0.6
0.0
0.8
0 0
0.0
0.0
0.0
0.8
0.8
0 8
0.0
0.8
0.8
0 8
0.0
0.8
Species richness
Speciation rate
0
25
50
75
100
Summary Statistics
−1.0
−0.5
0.0
0.5
1.0
Model
M0
M1
M2
M3
Summary statistic category
Trait metric correlations and distributions
Spatial metric correlations
Phylogenetic tree size and shape
Phylogenetic metric correlations
a)
b)
Range size ~ MRD ρ
Richness ~ MPD ρ
Temp. ~ body size SD ρ
Range size ~ ED ρ
Temp. ~ body size mean ρ
Richness ~ temp. ρ
Body size ~ temp. ρ
Latitude ~ MPD ρ
Richness ~ PD ρ
Latitude ~ MNTD ρ
Richness ~ body size SD ρ
Richness ~ body size mean ρ
Temp. kurtosis
Range size kurtosis
Temp. skewness
Temp. ~ MRD ρ
MNTD ~ Body size mean ρ
temp ~ ES ρ
Body size ~ range size ρ
Body size ~ MRD ρ
Range size ~ temp ρ
Body size ~ ES ρ
Sackin’s I
MPD ~ Body size mean ρ
γ
Clade size Variable importance scores
Std. mean summary statistic
0
25
50
75
100
Summary Statistics
−1.0
−0.5
0.0
0.5
1.0
Model
M0
M1
M2
M3
Summary statistic category
Trait metric correlations and distributions
Spatial metric correlations
Phylogenetic tree size and shape
Phylogenetic metric correlations
a)
Range size ~ MRD ρ
Richness ~ MPD ρ
Temp. ~ body size SD ρ
Range size ~ ED ρ
Temp. ~ body size mean ρ
Richness ~ temp. ρ
Body size ~ temp. ρ
Latitude ~ MPD ρ
Richness ~ PD ρ
Latitude ~ MNTD ρ
Richness ~ body size SD ρ
Richness ~ body size mean ρ
Temp. kurtosis
Range size kurtosis
Temp. skewness
Temp. ~ MRD ρ
MNTD ~ Body size mean ρ
temp ~ ES ρ
Body size ~ range size ρ
Body size ~ MRD ρ
Range size ~ temp ρ
Body size ~ ES ρ
Sackin’s I
MPD ~ Body size mean ρ
γ
Clade size Variable importance scores
Std. Model Selection mean
M0
M1
M2
M3
0.0
0.7
0 0
0.0
0
0.0
0.7
0 0
0.0
0.0
0
0.0
1.0
0 0
0.0
0
0.0
0.6
0.0
0.8
0 0
0.0
0.0
0.0
0.8
0.8
0 8
0.0
0.8
0.8
0 8
0.0
0.8
Species richness
Speciation rate
0
25
50
75
100
Summary Statistics
−1.0
−0.5
Summary statistic category
Trait metric correlations and distributions
Spatial metric correlations
Phylogenetic tree size and shape
Phylogenetic metric correlations
b)
Range size ~ MRD ρ
Richness ~ MPD ρ
Temp. ~ body size SD ρ
Range size ~ ED ρ
Temp. ~ body size mean ρ
Richness ~ temp. ρ
Body size ~ temp. ρ
Latitude ~ MPD ρ
Richness ~ PD ρ
Latitude ~ MNTD ρ
Richness ~ body size SD ρ
Richness ~ body size mean ρ
Temp. kurtosis
Range size kurtosis
Temp. skewness
Temp. ~ MRD ρ
MNTD ~ Body size mean ρ
temp ~ ES ρ
Body size ~ range size ρ
Body size ~ MRD ρ
Range size ~ temp ρ
Body size ~ ES ρ
Sackin’s I
MPD ~ Body size mean ρ
γ
Clade size
FIGURE 4. a) Scaled variable importance scores for 26 summary statistics based on model averaged variable importance factors from seven
machine learning algorithms (bottom panel). Distribution of mean ± standard error of 26 summary statistics across four population divergence
models (top panel). Different classes of summary statistics vary in their relative importance, for example, summary statistics based phylogenetic
metricsESorMRDwhichrelatetospeciationrates(lefthandcolumn,b)tendtodifferstronglybetweenmodelsandbehighlyinformative,whereas
summary statistics based on spatial correlations, particularly species richness (right hand column, b), tend to be uninformative. Phylogenetic
metric correlations are correlation coefficients between phylogenetic tip metrics (MRD, ES, ED, DR) and species-level traits (geographic range
size, mean temperature, body size). Spatial correlations are correlation coefficients between grid-cell level properties of assemblages (species
richness, MPD, MNTD, PD, mean body size, standard deviation of body size) and environmental properties (latitude or temperature). Trait
correlations and distributions relate to characteristics of species-level traits (body size, geographic range size, mean temperature). Phylogenetic
tree size and shape relates to clade size and the distribution of node heights ( ) or imbalance (Sackin’s I). b) The distribution of species-specific
speciation rates (grid cell averaged DR across species, left hand column) and species richness (right hand column) across four population
divergence models incorporating historical paleoenvironmental changes (M0–M3). Model Selection Using seven model classification algorithms, we
estimated the population divergence model of best fit
(Fig. 3c) as well as the proportional support for each
model (Fig. 3b) across 48 tetrapod orders. We found
that under all seven algorithms, a population divergence
model that included temperature dependency (M1)
was the best fitting model in the largest number of
clades. This varied between 16 clades with the neural
network algorithm to 38 clades with the naïve Bayes
algorithm. To incorporate uncertainty between classi-
fication model algorithms, we took a model averaged
estimate of model support, by weighing model support
by (Fig. 2b,c; Supplementary Table S4). We found M1
was best supported in the largest number of clades
(29 of 48), followed by the null model (M0; 9 clades),
the temperature- and body-size-dependent model (M3;
6 clades), and the body-size-dependent model (M2; 4
clades). Therefore, 35 clades (74.4%) had the strongest
support for a populationdivergencemodel thatincluded
temperature dependency (M1 and M3), compared with
no dependency (M0) or body-size dependency only
(M2). This general support for M1 in the data was
stronger when considering time-slice clades, or when
training the model only using low diversity simulations
(Supplementary Table S2). Estimating the relative pro-
portion of model support across classes allowed us to
look at the uncertainty implicit in model selection and
we found that the strength of support for each model was
variable. In some clades, support was predominantly g
y
y
A general effect of temperature (M1) was supported
across ecologically and geographically diverse tetrapod
clades with different thermoregulatory modes (ecto-
thermy and endothermy), whereas only weak support
for the role of body size was found (M2 and M3). The
ESH, as originally put forward by Rohde, argued that
evolutionary rates are dependent on both temperature
and life history (specifically generation time) (Rohde
1992). There is some empirical evidence for a relationship
between body size (and associated life history traits) and
substitution rates in vertebrates (Martin and Palumbi
1993), and we found support for a body-size-dependent
model of population divergence (M2 and M3) in several
large radiations, including skinks and allies (Scincoidea)
and frogs (Anura; Fig. 3c). However, more generally,
these models (M2 and M3) received only low support in
most clades (Fig. 3). This is partly because correlations SYSTEMATIC BIOLOGY
SYSTEMATIC BIOLOGY VOL. 72 350
10 Variable importance scores
Std. Model Selection Grid cell averaged values from each simulation were fist
standardized to be between 0 and 1 before an overall mean was taken for all complete simulations. ED = evolutionary distinctiveness measured
using the fair proportion measure; ES = equal splits measure of ED; DR = diversification rates measured as the inverse of ES; MRD = mean root
distance, MNTD = mean nearest taxon distance; MPD = mean pairwise distance; PD = phylogenetic diversity. Downloaded from https://academic.oup.com/sysbio/article/72/2/341/6637530 by ETH Zürich user on 21 June 2023 Downloaded from https://academic.oup.com/sysbio/article/72/2/341/6637530 by ETH Zürich user on 21 June 2023 Summary Statistics
R M0
M1
M2
M3
0.0
0.7
0 0
0.0
0
0.0
0.7
0 0
0.0
0.0
0
0.0
1.0
0 0
0.0
0
0.0
0.6
Species richness
Speciation rate
b) M0
M1
M2
M3
0.0
0.7
0 0
0.0
0
0.0
0.7
0 0
0.0
0.0
0
0.0
1.0
0 0
0.0
0
0.0
0.6
Speciation rate
b) b) FIGURE 4. a) Scaled variable importance scores for 26 summary statistics based on model averaged variable importance factors from seven
machine learning algorithms (bottom panel). Distribution of mean ± standard error of 26 summary statistics across four population divergence
models (top panel). Different classes of summary statistics vary in their relative importance, for example, summary statistics based phylogenetic
metricsESorMRDwhichrelatetospeciationrates(lefthandcolumn,b)tendtodifferstronglybetweenmodelsandbehighlyinformative,whereas
summary statistics based on spatial correlations, particularly species richness (right hand column, b), tend to be uninformative. Phylogenetic
metric correlations are correlation coefficients between phylogenetic tip metrics (MRD, ES, ED, DR) and species-level traits (geographic range
size, mean temperature, body size). Spatial correlations are correlation coefficients between grid-cell level properties of assemblages (species
richness, MPD, MNTD, PD, mean body size, standard deviation of body size) and environmental properties (latitude or temperature). Trait
correlations and distributions relate to characteristics of species-level traits (body size, geographic range size, mean temperature). Phylogenetic
tree size and shape relates to clade size and the distribution of node heights ( ) or imbalance (Sackin’s I). b) The distribution of species-specific
speciation rates (grid cell averaged DR across species, left hand column) and species richness (right hand column) across four population
divergence models incorporating historical paleoenvironmental changes (M0–M3). Grid cell averaged values from each simulation were fist
standardized to be between 0 and 1 before an overall mean was taken for all complete simulations. Model Selection Another theory, based
on the red queen hypothesis (Van Valen 1973), is that
lineages in high-energy environments have higher rates
of divergence as a result of strong divergent selection
from interactions with different species (Gillman et al. 2009; Schemske et al. 2009). Taken together, our results
suggest an integral role of temperature in driving rates of
population divergence and generating biodiversity pat-
terns. However, the exact mechanism differs from that
predicted by the original ESH (Rohde 1992), with rates
dependent on body size as a proxy for life history being
less supported. Further work disentangling the drivers
of faster rates of divergence in warm areas, whether from
population size effects related to productivity or biotic
interactions, is a key next step. y
p
We found overall support for temperature-dependent
rates of population divergence in terrestrial vertebrates,
despiteobservingonlyweaksupportforthatmechanism
from individual summary statistics. Meta-analyses of
correlation coefficients in tetrapods showed that, despite
an overall significant and positive effect of temperature
on species richness which is consistent with findings
from previous studies (Currie 1991; Belmaker and Jetz
2011; Skeels et al. 2019), there was no significant effect
of temperature on speciation rates (Fig. 3). In fact, using
PGLS, only 10 clades showed a significant positive cor-
relation between temperature and species-specific speci-
ation rates (DR statistic [Jetz et al. 2012]), compared with
13 clades showing a significant negative correlation—
with rates being higher in lineages occupying colder
regions (Supplementary Appendix S4). This result
matches several recent studies in which higher diver-
sification rates were found in higher-latitude regions
(with lower temperatures) (Weir and Schluter 2008b;
Rabosky et al. 2018). This may reflect a geographic bias
in how species are taxonomically described (Freeman
and Pennell 2021), an artifact of studying rate variation
over short timescales (Harmon et al. 2021), or it may
reflect genuinely different mechanisms operating across
latitudes (Cutter and Gray 2016). Our simulations help
to elucidate this point and can also explain why we
see support for temperature dependency, despite weak
or inconsistent individual patterns. Holding the rates
of population divergence constant, speciation in the
null model (M0) is only a function of the rate of
population isolation, and here we see the highest rates
at higher latitudes. Model Selection ED = evolutionary distinctiveness measured
using the fair proportion measure; ES = equal splits measure of ED; DR = diversification rates measured as the inverse of ES; MRD = mean root
distance, MNTD = mean nearest taxon distance; MPD = mean pairwise distance; PD = phylogenetic diversity. SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY 351
11 2023
2022 selection to act upon (Fine 2015). Another theory, based
on the red queen hypothesis (Van Valen 1973), is that
lineages in high-energy environments have higher rates
of divergence as a result of strong divergent selection
from interactions with different species (Gillman et al. 2009; Schemske et al. 2009). Taken together, our results
suggest an integral role of temperature in driving rates of
population divergence and generating biodiversity pat-
terns. However, the exact mechanism differs from that
predicted by the original ESH (Rohde 1992), with rates
dependent on body size as a proxy for life history being
less supported. Further work disentangling the drivers
of faster rates of divergence in warm areas, whether from
population size effects related to productivity or biotic
interactions, is a key next step. between body size and the equal splits measure of
evolutionary distinctiveness (Redding and Mooers 2006;
Jetz et al. 2012), the most important summary statistic for
model discrimination (Fig. 4), had higher values in M2
and M3 than the empirical data, which was more closely
matching M0 and M1. Instead, our results show the
greatest support for a predominant role of temperature
in shaping rates of divergence (M1). This was, in addition
to the ES-richness correlation, also strongly determined
by a more negative correlation between geographic
range size and temperature in both empirical and M1
data—the second most important summary statistic
(Fig. 4). This is expected if speciation is temperature-
dependent because, if allopatric speciation is a process
which divides species geographic ranges, and speciation
happens faster in warm places, then warm places should
have more species with overall smaller geographic
ranges. Therefore, our results suggest that temperature-
dependent speciation could contribute to Rapoport’s
rule—the observation that geographic ranges become
smaller toward the tropics (Stevens 1989)—and that this
phenomenon is not inconsistent with the ESH (Rohde
1992, 1996). selection to act upon (Fine 2015). Model Selection The absence of ice-cover
in our model inputs may also affect this result, as
the only constraint on dispersal in polar regions is
the temperature niche of species. These processes also
lead to incongruence between regions of high species
richness, high temperatures, and high speciation rates
(Fig. 4b). Therefore, support for the ESH drawn from
the spatial distribution of speciation rates may be at risk
of misinterpreting the strong signal of recent population
fragmentation as an absence of evidence of temperature-
driven population divergence. Our results suggest that
the spatial distribution of speciation rates should be
interpreted cautiously, ideally with the simultaneous
assessment of multiple biodiversity patterns, before
drawing inferences. temperature-dependent evolutionary rates in the form-
ation of multiple biodiversity patterns, the ESH is not
necessarily the primary cause of the latitudinal diversity
gradient, as this pattern is indistinguishable between the
null and alternative models (Fig. 4). However, we note
that local abundances in our model were determined
by three factors, the match between environmental
temperature and the thermal niche of species, the aridity
of the site, and the presence of other species. Hence, the
potential species richness of a site at equilibrium would
be environmentally determined, which explain similar
patterns of species richness between models, despite
underlying differences in macroevolutionary rates. This
fits with the understanding that equilibrium effects can
mask historical dynamics for particular metrics, such as
species richness; however, notable differences between
other summary statistics suggest that historical effects
can be detected with a multivariate metric approach. g
Predictive models should match different patterns
simultaneously because evolutionary processes have
downstream impacts on a whole suite of biodiversity
patterns (Gallagher et al. 2021; Hagen, Flück et al. 2021). In this study, we used an uncorrelated subset
of 26 out of 54 different summary statistics to perform
inference, which covered a vast array of biodiversity
patterns. These included some of the most well-known
and ubiquitous macroecological patterns, including the
relationship between latitude and geographic range size
(Rapoport’s rule [Stevens 1989]), between body size and
temperature (Bergmann’s rule [Bergmann 1847]), and
between latitude and species richness (the latitudinal
diversity gradient [Hillebrand 2004]). These kinds of
macroecological patterns are not always considered
when testing macroevolutionary theories such as the
ESH. Caveats and Future Directions The common support for a temperature-dependent
model was robust to several different analysis strategies,
including taxonomic and clade size sampling strategies
(Supplementary Appendix S4); however, there are fea-
tures of the simulation models and empirical data
that may still introduce biases to the results. The
simulations varied in the models of population diver-
gence yet had the same functions for dispersal, trait
evolution, and ecological interactions. Where possible,
we selected functions that have been used successfully
in the literature before. For example, models including
environmentally determined carrying capacities yield
a consistently better fit to empirical data across differ-
ent kinds of simulation models (Hurlbert and Stegen
2014b; Hagen, Flück et al. 2021). Yet some models may
incompletely represent real processes. For example, a
Brownian Motion model of trait evolution does not
always produce the right skew in body size distributions
of real clades (Kozłowski and Gawelczyk 2002), and
summary statistics of the frequency distribution of
body size in our study were some that showed the
least congruence with empirical data. The field of
spatially explicit simulation modeling is emerging and
exploration of different kinds of ecological models is
still in its infancy (Pontarp et al. 2019). As such, some
modeling decisions were not exhaustively explored in
this study, such as the starting time and distribution of
theinitialspeciesinthesimulations,aswellasalternative
paleoenvironmental reconstructions. p
y p
We found that most summary statistics showed
very high congruence between simulated and empir-
ical datasets, supporting the validity of the model in
generating realistic patterns. We also found that many
broadscale macroecological patterns differed between
population divergence models, for example, the correl-
ation between geographic range size and temperature
was considered the second most important explanatory
summary statistic (Fig. 4a), and the combination of
the most informative summary statistics considered
different dimensions of biodiversity (Fig. 4a). However,
somesummarystatistics,includingcorrelationsbetween
species richness and latitude or temperature, showed
little variation between population divergence models
(Figs. 2d and 4b). The ESH was originally formulated
as an explanation for the latitudinal diversity gradient
based on the premise that other explanations, such as
environmental stability (Pianka 1966b), biotic interac-
tions (Dobzhansky 1950), geographic area (Rosenzweig
1995), and evolutionary time (Fischer 1960), have weak
or partial explanatory power (Rohde 1992). Model Selection When introducing a temperature-
dependent rate of population divergence (M1), we see
the distribution of high speciation rates becoming more
equatorial, with some of the highest values occurring
in the deserts and grasslands of the Afrotropics where
richness is often low (Fig. 4b). Yet even under M1,
correlations between speciation rates and temperature
were highly variable and often negative. This tells us
that rates of population isolation are greater in colder
regions, but this pattern can be counter-balanced by
rapid population divergence in warmer regions, high-
lighting a potentially very important effect of climatic
stability on the formation of biodiversity (Pianka 1966a; The estimated support for a temperature-dependent
model of population divergence provides support for
the ESH; however, it remains an open question exactly
how temperature shapes rates of divergence in real
clades. As originally described by Rohde (1992), the
ESH makes predictions based on largely on variation in
rates of molecular evolution with temperature. Empir-
ical support for greater UV-damage-driven molecular
evolution is weak, as it should also apply to high-
elevation lineages, which have showed the opposite
pattern of lower rates (Wright et al. 2010). Although the
basal metabolic-pathway explanation makes separate
predictions for ectotherms and endotherms (which we
do not see in our results), as endotherms maintain a
constant body temperature across environmental tem-
perature gradients (Gillman et al. 2009). We therefore
find these explanations unlikely. On the other hand,
variation in annual metabolic rates, which are expected
to be lower in species occupying more seasonal climates
which undergo hibernation or torpor during colder
months (Gillman and Wright 2013), remains a plausible
explanation. It is also possible that population divergence in real
clades may be accelerated by an unmeasured factor
that is correlated with temperature but uncorrelated
(or weakly correlated) with body size. For example,
some hypotheses and empirical data suggest popu-
lation sizes are expected to be smaller in warmer
regions because increased productivity drives negative
density-dependent population dynamics from greater
competition, predation, or trophic diversity (Paine 1966;
Janzen 1970; Connell and Orias 1964), leading to faster
rates of molecular evolution (Kimura 1983; Ohta 1992;
Woolfit 2009). Alternatively, greater productivity could
increase population sizes (Storch et al. 2018), leading
to more genetic diversity and standing variation for SYSTEMATIC BIOLOGY
SYSTEMATIC BIOLOGY VOL. 72 352
12 VOL. 72 Dynesius and Jansson 2000b). Model Selection However, any evolutionary process that generates
biodiversity and operates over deep time should leave
detectable signatures not only in the shape of phylogen-
etic branching patterns and their correlates, but also in
spatial diversity patterns (McGill et al. 2019). CONCLUSION By explicitly considering evolutionary and ecolo-
gical mechanisms alongside dynamic changes in plate
tectonics and temperature over the Cenozoic using a
simulation-based inference approach, we found strong
support that temperature-dependent population diver-
gence shapes speciation rates and broad-scale biod-
iversity patterns across tetrapods. Counter-intuitively,
we show that a positive relationship between temper-
ature and species richness does not provide sufficient
evidence that temperature plays a generative role in
lineage diversification, whereas a negative relationship
between temperature and speciation rate does not
provide sufficient evidence to negate a generative role
of temperature in lineage diversification. Instead, model
support was derived from numerous summary statistics,
highlighting that multiple lines of evidence should
be combined before precluding specific mechanisms. This has important implications; given that most real
clades show weak relationships between temperature
and diversification rates (Fig. 3e), dismissals in pre-
vious studies of the role of temperature in shaping
evolutionary speed must be reassessed. Simulation-
based approaches, such as the one used in this study,
allow us to compare complex and spatially-dynamic
models of evolution and place uncertainty intervals on
different evolutionary mechanisms. We can now ask, in
light of multidimensional biodiversity patterns, which
evolutionary mechanisms appear more probable. We
hope that future studies might extend this hypothesis
testing framework using spatial simulation models
to test more hypotheses for the formation of global
biodiversity patterns, enabling us to move toward a more
comprehensive assessment of the processes generating
the extraordinary diversity of life today. p
Another potential source of bias may arise from the
analysis of congruence between simulated and empirical
data. Simulated data represented a perfectly known his-
tory of a clade, whereas empirical data are incompletely
sampled and contains both measurement error in spatial
and trait data as well as potential biases in phylogenetic
reconstructions. If biases present in empirical sampling
are biased with respect to traits, such as body size,
then this may impact subsequent correlations with other
features such as diversification rates, particularly if these
features are intercorrelated (e.g., smaller body sized
organisms diversify faster). We used body size as a trait
representing life history as this trait is very well sampled
across tetrapods (Etard et al. 2020), but sampling for
this trait as well as molecular data used in phylogenetic
inference are more sparse in herptile clades than birds
and mammals (Jetz et al. 2012; Tonini et al. 2016; Jetz and
Pyron 2018; Upham et al. Caveats and Future Directions Here, we
argue that although there is strong support for the role of One specific process that may help to further elucidate
the mechanisms underlying observed support for the
temperature-dependent model is incorporating an effect
of population size on population divergence directly. In this study, we model population size based on
the thermal niche requirements of the species and
limiting water availability, but for simplicity, we do
not model an interaction between population size and
population divergence. Population size may influence SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY 353
13 2023
2022 2012) and in climate (Dynesius and Jansson 2000a). These
hypotheses inherently include effects of temperature
and redeveloping the simulation methodology to cleanly
delineate these signals was outside the scope of this
work which had a focus on evolutionary speed. Studies
which include counter-factual case-studies provide a
potentially valuable method of separating confounding
effects. For example, some previous simulation studies
modified historical landscapes to remove the effects of
mountain building (Rangel et al. 2018), or aridification
(Hagen, Skeels et al. 2021), to explore how diversification
may have proceeded had these Earth history events
never occurred. In this vein, we propose that removing
historical climate and landscape changes or modifying
their velocities could offer a way to separate the effects. We highlight this as a promising area for future work. 2012) and in climate (Dynesius and Jansson 2000a). These
hypotheses inherently include effects of temperature
and redeveloping the simulation methodology to cleanly
delineate these signals was outside the scope of this
work which had a focus on evolutionary speed. Studies
which include counter-factual case-studies provide a
potentially valuable method of separating confounding
effects. For example, some previous simulation studies
modified historical landscapes to remove the effects of
mountain building (Rangel et al. 2018), or aridification
(Hagen, Skeels et al. 2021), to explore how diversification
may have proceeded had these Earth history events
never occurred. In this vein, we propose that removing
historical climate and landscape changes or modifying
their velocities could offer a way to separate the effects. We highlight this as a promising area for future work. evolutionary speed via its effect on the rate in which
different kinds of mutations go to fixation (Lanfear et al. Caveats and Future Directions 2014; Hua and Bromham 2017), with the expectation
that beneficial mutations are fixed at a higher rate in
larger populations and slightly-deleterious mutations
are fixed at a higher rate in small populations, but the
rate of substitution for effectively neutral mutations is
independent of population size (Lanfear et al. 2014). This
means that if most mutations are slightly deleterious
the average rate of molecular evolution should decrease
with increasing population size (Lanfear et al. 2014),
such that smaller populations might diverge more
rapidly from one another, leading to faster rates of
speciation. Alternatively, the integrated ESH (Gillman
and Wright 2013) predicts that a greater efficiency of
fixing beneficial mutations in larger populations may
lead to greater adaptive potential, leading to local adapt-
ation and ecological divergence between populations,
driving more rapid speciation. A subsequent prediction
of the integrated ESH is that aridity not only effects
population size, but also might indirectly drive variation
in evolutionary speed, and this is supported in some
taxa (Goldie et al. 2010). These two models are amenable
to testing using the simulation-based approach taken
here and this possible future direction may help clarify
the most likely effect of population size on evolutionary
speed. REFERENCES Allen A.P., Brown J.H., Gillooly J.F. 2002. Global biodiversity, biochem-
ical kinetics, and the energetic-equivalence rule. Science 297:1545–
1548. Dobzhansky T. 1950. Evolution in the tropics. Am. Sci. 38:209–211. Dobzhansky T. 1982. Genetics and the origin of species. New York:
Columbia University Press. Allen A.P., Gillooly J.F., Brown J.H. 2012. Recasting the species–energy
hypothesis: the different roles of kinetic and potential energy in
regulating biodiversity. In: Storch D., Marquet P., Brown J., editors. Scaling Biodiversity. Cambridge (UK): Cambridge University Press. p. 283–299. y
Dowle E.J., Morgan-Richards M., Trewick S.A. 2013. Molecular evol-
ution and the latitudinal biodiversity gradient. Heredity (Edinb). 110:501–510. Dynesius M., Jansson R. 2000a. Evolutionary consequences of
changes in species’ geographical distributions driven by Mil-
ankovitch climate oscillations. Proc. Natl. Acad. Sci. U. S. A. 97:9115–9120. Allen A.P., Gillooly J., Brown J.H. 2007. Recasting the species-energy
hypothesis: the different roles of kinetic and potential energy in
regulating biodiversity. In: Storch D., Marquet P.A. and Brown
J.H., editors. Scaling biodiversity. Cambridge (UK): Cambridge
University Press. p. 283–299. Dynesius M., Jansson R. 2000b. Evolutionary consequences of changes
in species’ geographical distributions driven by Milankovitch
climate oscillations. Proc. Natl. Acad. Sci. U. S. A. 97:9115–9120. y
p
Allen A.P., Gillooly J.F., Savage V.M., Brown J.H. 2006. Kinetic effects
of temperature on rates of genetic divergence and speciation. Proc. Natl. Acad. Sci. U. S. A. 103:9130–9135. Economo E.P., Huang J.P., Fischer G., Sarnat E.M., Narula N., Janda
M., Guénard B., Longino J.T., Knowles L.L. 2019. Evolution of
the latitudinal diversity gradient in the hyperdiverse ant genus
Pheidole. Glob. Ecol. Biogeogr. 28:456–470. Barrera-Redondo J., Ramírez-Barahona S., Eguiarte L.E. 2018. Rates
of molecular evolution in tree ferns are associated with body size,
environmental temperature, and biological productivity. Evolution. 72:1050–1062. g
g
Etard A., Morrill S., Newbold T. 2020. Global gaps in trait data for
terrestrial vertebrates. Glob. Ecol. Biogeogr. 29:2143–2158. Faurby S., Davis M., Pedersen R.Ø., Schowanek S.D., Antonelli1 A.,
Svenning J.-C. 2018. PHYLACINE 1.2: the phylogenetic atlas of
mammal macroecology. Ecology. 99:2626. Belmaker J., Jetz W. 2011. Cross-scale variation in species richness–
environment associations. Glob. Ecol. Biogeogr. 20:464–474. g
g
Bergmann C. 1847. Ober die Verhaltnisse der Warmeokonomie der
Thiere zu ihrer Grosse. Gottinger Stud. 3:595–708. Feldman A., Sabath N., Pyron R.A., Mayrose I., Meiri S. 2016. Body sizes
and diversification rates of lizards, snakes, amphisbaenians and the
tuatara. Glob. Ecol. Biogeogr. 25:187–197. g
Bromham L. 2002. AUTHOR CONTRIBUTIONS y
y
p
Cardillo M. 1999. Latitude and rates of diversification in birds and
butterflies. Proc. R. Soc. B Biol. Sci. 266:1221–1225. All authors made significant intellectual contributions
to the manuscript. A.S. and L.P. conceived the study. A.S. performed all analyses. A.S., W.B., O.H., W.J., and
L.P. contributed to designing the study and writing the
manuscript. L.P. supervised the project. Cohen J. 1960. A coefficient of agreement for nominal scales. Educ. Psychol. Meas. 20:37–46. Colston T.J., Kulkarni P., Jetz W., Pyron R.A. 2020. Phylogenetic and
spatial distribution of evolutionary isolation and threat in turtles
and crocodilians (non-avian archosauromorphs). BMC Evol. Biol. 20:1–16. Condamine F.L., Rolland J., Morlon H. 2013. Macroevolutionary
perspectives to environmental change. Ecol. Lett. 16:72–85. Connell J.H., Orias E. 1964. The ecological regulation of species
diversity. Am. Nat. 98(903):399–414. DATA AND CODE AVAILABILITY STATEMENT No new data were generated for this study and all
data used were from publicly available data sources. All
simulations and analyses were performed in R, version
4.0.3 (R Core Team 2020). All R scripts to replicate
the simulations and analyses from the empirical
data can be found on GitHub (www.github.com/
alexskeels/gen3sis_evolutionary_speed)
and
are
also available from the Dryad Digital Repository:
https://doi.org/10.5061/dryad.cnp5hqc71. Cooke R.S.C., Bates A.E., Eigenbrod F. 2019. Global trade-offs of
functional redundancy and functional dispersion for birds and
mammals. Glob. Ecol. Biogeogr. 28:484–495. g
g
Coyne J.A., Orr H.A. 2004. Speciation. Sunderland (MA): Sinauer
Associates, Inc. Currie D.J. 1991. Energy and large-scale patterns of animal- and plant-
species richness. Am. Nat. 137:27–49. p
Cutter A.D., Gray J.C. 2016. Ephemeral ecological speciation and the
latitudinal biodiversity gradient. Evolution. 70:2171–2185. l
h
l Davies T.J., Savolainen V., Chase M.W., Moat J. 2004. Environmental
energy and evolutionary rates in flowering plants. Proc. Biol. Sci. 271:2195–2200. Descombes P., Gaboriau T., Albouy C., Heine C., Leprieur F., Pellissier
L. 2018. Linking species diversification to palaeo-environmental
changes: a process-based modelling approach. Glob. Ecol. Biogeogr. 27:233–244. ACKNOWLEDGMENTS Bromham L., Cardillo M. 2003. Testing the link between the latitudinal
gradient in species richness and rates of molecular evolution. J. Evol. Biol. 16:200–207. We thank the Keogh Lab, Moritz Lab, the Macro-
evolution and Macroecology Group at the Australian
National University, and members of the Ecosystem and
Landscape Evolution group at ETH and WSL, as well as
three anonymous reviewers for feedback. We are grateful
to Benjamin Flück at ETH Zurich for technical support
and to Melissa Dawes for feedback and proofing the
manuscript. Bromham L., Hua X., Lanfear R., Cowman P. 2015. Exploring the
relationships between mutation rates, life history, genome size,
environment and species richness in flowering plants. Am. Nat. 185:507. Bromham L., Rambaut A., Harvey P.H. 1996. Determinants of rate
variation in mammalian DNA sequence evolution. J. Mol. Evol. 43:610–621. Brown J.H. 2004. Toward a metabolic theory of ecology. Ecology. 85:1771–1789. Brown J.H., Banks J., Belt T., Von A., Hooker J.D., Darwin C. 2014. Why are there so many species in the tropics? J. Biogeogr. 1905:
8–22. FUNDING
A.S., W.B., and L.P. were supported by the SNSF
project “Bigest” 310030_188550. Burhenne S., Jacob D., Henze G.P. 2011. Sampling based on sobol’
sequences for monte carlo techniques applied to building simula-
tions. Proceedings of Building Simulation 2011: 12th Conference of
International Building Performance Simulation Association; Nov. 14–16; Sydney. 1816–1823 p. CONCLUSION 2019; Etard et al. 2020). Herptile
clades have fundamentally different predictions under
the metabolic-theory interpretation of the ESH based
on their thermal regulatory mode, and potential biases
here might have important consequences. Nonetheless,
sampling of body size in herptile families is greater
than 80% (Etard et al. 2020) and we suspect the main
relationships should be robust to this taxonomic bias. Sampling bias across taxa highlights the value of field-
based and data collection studies that support large
comparative studies such as this one. Finally, we acknowledge that our approach to assess-
ing the ESH hypothesis prevented us from and explicit
separation of, and comparison with, key alternative
hypotheses such as the past dynamics in the available
area of suitable habitat and productivity (Jetz and Fine SUPPLEMENTARY MATERIAL
Data available from the Dryad Digital Repository:
https://doi.org/10.5061/dryad.cnp5hqc71 354
14 SYSTEMATIC BIOLOGY
SYSTEMATIC BIOLOGY VOL. 72 VOL. 72 SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY Lanfear R., Thomas J.A., Welch J.J., Brey T., Bromham L. 2007. Metabolie
rate does not calibrate the molecular clock. Proc. Natl. Acad. Sci. U. S. A. 104:15388–15393. y
Gillooly J.F., Allen A.P. 2007. Linking global patterns in biodiversity
to evolutionary dynamics using metabolic theory. Ecology 88:1890–
1894. Lourenço J.M., Glémin S., Chiari Y., Galtier N. 2013. The determinants
of the molecular substitution process in turtles. J. Evol. Biol. 26:38–50. Gillooly J.F., Allen A.P., West G.B., Brown J.H. 2005. The rate of DNA
evolution: effects of body size and temperature on the molecular
clock. Proc. Natl. Acad. Sci. U. S. A. 102:140–145. Lynch M. 2010. Evolution of the mutation rate. Trends Genet. 26:345–352. Goldie X., Gillman L., Crisp M., Wright S. 2010. Evolutionary
speed limited by water in arid Australia. Proc. Biol. Sci. 277:
2645–2653. Marin J., Hedges S.B. 2016. Time best explains global variation in
species richness of amphibians, birds and mammals. J. Biogeogr. 43:1069–1079. Martin A.P., Palumbi S.R. 1993. Body size, metabolic rate, generation
time, and the molecular clock. Proc. Natl. Acad. Sci. U. S. A. 90:4087–
4091. Hagen O., Flück B., Fopp F., Cabral J.S., Hartig F., Pontarp M., Rangel
T.F., Pellissier L. 2021. gen3sis: a general engine for eco-evolutionary
simulations of the processes that shape Earth’s biodiversity. PLoS
Biol. 19:e3001340. McGill B.J., Chase J.M., Hortal J., Overcast I., Rominger A.J., Rosindell
J., Borges P.A.V., Emerson B.C., Etienne R., Hickerson M.J., Mahler
D.L., Massol F., McGaughran A., Neves P., Parent C., Patiño J.,
Ruffley M., Wagner C.E., Gillespie R. 2019. Unifying macroeco-
logy and macroevolution to answer fundamental questions about
biodiversity. Glob. Ecol. Biogeogr. 28:1925–1936. Hagen O., Skeels A., Onstein R.E., Jetz W., Pellissier L. 2021. Earth
history events shaped the evolution of uneven biodiversity across
tropical moist forests. Proc. Natl. Acad. Sci. U. S. A. 118: e2026347118. Hagen O., Vaterlaus L., Albouy C., Brown A., Leugger F., Onstein
R.E., de Santana C.N., Scotese C.R., Pellissier L. 2019. Mountain
building, climate cooling and the richness of cold-adapted plants
in the Northern Hemisphere. J. Biogeogr. 46:1792–1807. McHugh M.L. 2012. Interrater reliability: the kappa statistic. Biochem. Medica. 22:276–282. Harmon L.J., Harrison S. 2015. Species diversity is dynamic and
unbounded at local and continental scales. Am. Nat. 185:584–593. McPeek M.A. 2007. The macroevolutionary consequences of ecological
differences among species. Palaeontology. 50:111–129. McPeek M.A. 2008. The ecological dynamics of clade diversification
and community assembly. Am. Nat. 172:E270–E284. SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY 355
15 SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY Fine P.V.A. 2015. Ecological and evolutionary drivers of geographic
variation in species diversity. Annu. Rev. Ecol. Evol. Syst. 46:369–392. Jetz W., Fine P.V.A. 2012. Global gradients in vertebrate diversity pre-
dicted by historical area-productivity dynamics and contemporary
environment. PLoS Biol. 10:e1001292. Fine P.V.A., Ree R.H. 2006. Evidence for a time-integrated species-
area effect on the latitudinal gradient in tree diversity. Am. Nat. 168:796–804. Jetz W., Pyron R.A. 2018. The interplay of past diversification
and evolutionary isolation with present imperilment across the
amphibian tree of life. Nat. Ecol. Evol. 2:850–858. Fischer A.G. 1960. Latitudinal variations in organic diversity. Evolution
(N. Y). 14:64–81. p
Jetz W., Thomas G.H., Joy J.B., Hartmann K., Mooers A.O. 2012. The
global
diversity
of
birds
in
space
and
time. Nature. 491:444–448. Freeman B.G., Pennell M.W. 2021. The latitudinal taxonomy gradient. Trends Ecol. Evol. 1:1–9. Karger D.N., Conrad O., Böhner J., Kawohl T., Kreft H., Soria-
Auza R.W., Zimmermann N.E., Linder H.P., Kessler M. 2017. Climatologies at high resolution for the earth’s land surface areas. Sci. Data. 4:1–20. Gallagher C.A., Chudzinska M., Larsen-Gray A., Pollock C.J., Sells S.N.,
White P.J.C., Berger U. 2021. From theory to practice in pattern-
oriented modelling: identifying and using empirical patterns in
predictive models. Biol. Rev. Camb. Philos. Soc. 96:1868–1888. Kimura M. 1983. The neutral theory of molecular evolution. Cambridge
(UK): Cambridge University Press. p
Gillman L.N., Keeling D.J., Ross H.A., Wright S.D. 2009. Latitude,
elevation and the tempo of molecular evolution in mammals. Proc. Biol. Sci. 276:3353–3359. g
y
Kozłowski J., Gawelczyk A.T. 2002. Why are species’ body size
distributions usually skewed to the right? Funct. Ecol. 16:419–432. Gillman L.N., Mccowan L.S.C., Wright S.D. 2012. The tempo of genetic
evolution in birds: body mass and climate effects. J. Biogeogr. 39:1567–1572. Lanfear R., Ho S.Y.W., Davies T.J., Moles A. T. Aarssen L., Swenson
N.G., Warman L., Zanne A.E., Allen A.P. 2013. Taller plants have
lower rates of molecular evolution: the rate of mitosis hypothesis. Nat. Commun. 4:1879. Gillman L.N., Wright S.D. 2006. The influence of productivity on the
species richness of plants: a critical assessment. Ecology 87:1234–
1243. Lanfear R., Kokko H., Eyre-Walker A. 2014. Population size and the rate
of evolution. Trends Ecol. Evol. 29:33–41. Gillman L.N., Wright S.D. 2013. Patterns of evolutionary speed: in
search of a causal mechanism. Diversity 5:811–823. SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY Harmon L.J., Pennell M.W., Henao-Diaz L.F., Rolland J., Sipley B.N.,
Uyeda J.C. 2021. Causes and Consequences of apparent timescaling
across all estimated evolutionary rates. Annu. Rev. Ecol. Evol. Syst. 52:587–609. y
y
Meiri S. 2008. Evolution and ecology of lizard body sizes. Glob. Ecol. Biogeogr. 17:724–734. Hillebrand H. 2004. On the generality of the latitudinal diversity
gradient. Am. Nat. 163:192–211. g
g
Meiri S. 2010. Length weight allometries in lizards. J. Zool. 281:218–226. g
g
Meiri S. 2018. Traits of lizards of the world: variation around a
successful evolutionary design. Glob. Ecol. Biogeogr. 27:1168–1172. g
Hua X., Bromham L. 2017. Darwinism for the genomic age: connecting
mutation to diversification. Front. Genet. 8:1–18. Meseguer A.S., Condamine F.L. 2020. Ancient tropical extinctions
at high latitudes contributed to the latitudinal diversity gradient. Evolution. 74:1966–1987. Hua X., Cowman P., Warren D., Bromham L. 2015. Longevity is linked
to mitochondrial mutation rates in rockfish: a test using Poisson
regression. Mol. Biol. Evol. 32:2633–2645. Miller E.C., Hayashi K.T., Song D., Wiens J.J. 2018. Explaining the
ocean’s richest biodiversity hotspot and global patterns of fish
diversity. Proc. Biol. Sci. 285:20181314. g
Hurlbert A.H., Stegen J.C. 2014a. When should species richness be
energy limited, and how would we know Ecol. Lett. 17:401–413. y
Ohta T. 1992. The nearly neutral theory of molecular evolution. Annu. Rev. Ecol. Syst. 23:263–286. Hurlbert A.H., Stegen J.C. 2014b. On the processes generating lat-
itudinal richness gradients: identifying diagnostic patterns and
predictions. Front. Genet. 5:1–9. Oliveira B.F., São-Pedro V.A., Santos-Barrera G., Penone C., Costa G.C. 2017. AmphiBIO, a global database for amphibian ecological traits. Sci. Data. 4:170123. p
Hurlbert A.H., Stegen J.C. 2014c. When should species richness be
energy limited , and how would we know?? Ecol. Lett. 17:401–413. OrtonM.G.,MayJ.A.,LyW.,LeeD.J.,AdamowiczS.J.2019.Ismolecular
evolution faster in the tropics? Heredity (Edinb). 122:513–524. gy
International
Union
for
Conservation
of
Nature. 2016. The
IUCN
red
list
of
threatened
species. Available
from:
https://www.iucnredlist.org/. p
y
Paine R.T. 1966. Food web complexity and species diversity. Am. Nat. 100:65–75. p
g
Ivan J., Moritz C., Potter S., Bragg J., Turakulov R., Hua X. 2022. Temperature predicts the rate of molecular evolution in Australian
Eugongylinae skinks. Evolution 72:252–261. Pianka E.R. 1966a. Latitudinal gradients in species diversity: a review
of concepts. Am. Nat. 100:33–46. g
gy
Janzen D.H. 1970. Herbivores and the number of tree species in tropical
forests. Am. Nat. 104:501–528. Pianka E.R. 1966b. Latitudinal gradients in species diversity: a review
of concepts. Am. REFERENCES Molecular clocks in reptiles: life history influences
rate of molecular evolution. Mol. Biol. Evol. 19:302–309. 2023
2022 SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY Nat. 100:33–46. 356
16 SYSTEMATIC BIOLOGY
SYSTEMATIC BIOLOGY VOL. 72 VOL. 72 Pontarp M., Bunnefeld L., Cabral J.S., Etienne R.S., Fritz S.A., Gillespie
R., Graham C.H., Hagen O., Hartig F., Huang S., Jansson R., Maliet
O., Münkemüller T., Pellissier L., Rangel T.F., Storch D., Wiegand T.,
Hurlbert A.H. 2019. The latitudinal diversity gradient: novel under-
standing through mechanistic eco-evolutionary models. Trends
Ecol. Evol. 34:211–223. Santos J.C. 2012. Fast molecular evolution associated with high active
metabolic rates in poison frogs. Mol. Biol. Evol. 29:2001–2018. g
Saupe E.E., Myers C.E., Townsend Peterson A., Soberón J., Singarayer J.,
Valdes P., Qiao H. 2019. Spatio-temporal climate change contributes
to latitudinal diversity gradients. Nat. Ecol. Evol. 3:1419–1429. y g
Schemske D.W., Mittelbach G.G., Cornell H. V., Sobel J.M., Roy K. 2009. Is there a latitudinal gradient in the importance of biotic
interactions? Annu. Rev. Ecol. Evol. Syst. 40:245–269. Promislow D., Clobert J., Barbault R. 1992. Life history allometry
in mammals and squamate reptiles: taxon-level effects. Oikos. 65:285–294. y
Schluter D., Conte G.L. 2009. Genetics and ecological speciation. Proc. Natl. Acad. Sci. U. S. A. 106:9955–9962. Prowse T.A.A., Bradshaw C.J.A., Delean S., Cassey P., Lacy R.C., Wells
K., Aiello-Lammens M.E., Akçakaya H.R., Brook B.W. 2016. An
efficient protocol for the global sensitivity analysis of stochastic
ecological models. Ecosphere. 7:e01238. ScoteseC.R.,SongH.,MillsB.J.W.,vanderMeerD.G.2021.Phanerozoic
paleotemperatures: the earth’s changing climate during the last 540
million years. Earth Sci. Rev. 215:103503. Qiu F., Kitchen A., Burleigh J.G., Miyamoto M.M. 2014. Scombroid
fishes provide novel insights into the trait/rate associations of
molecular evolution. J. Mol. Evol. 78:338–348. Scotese C.R., Wright N. 2018. PALEOMAP Paleodigital Elevation
Models
(PaleoDEMS)
for
the
Phanerozoic. Available
from:
https://www.earthbyte.org/paleodem-resource-scotese-and-
wright-2018. Downloaded from https://academic.oup.com/sysbio/article/72/2/341/6637530 by ETH Zürich user on 21 June 2023 Quintero I., Jetz W. 2018. Global elevational diversity and diversifica-
tion of birds. Nature. 555:246–250. Signorell
A. 2021. DescTools:
tools
for
descriptive
statistics. R
package
version
0.99.43. Available
from:
https://cran.r-
project.org/package=DescTools. R Core Team. 2020. R: a language and environment for statistical com-
puting. Vienna (Austria): R Foundation for Statistical Computing. Available from: https://www.R-project.org/. p
j
g p
g
Skeels A., Esquerré D., Cardillo M. 2019. Alternative pathways to
diversity across ecologically distinct lizard radiations. Glob. Ecol. Biogeogr. 29:454–469. p
p
j
g
Rabosky D.L. 2021. Macroevolutionary thermodynamics: temperature
and the tempo of evolution in the tropics. PLOS Biol. 19:e3001368. g
g
Stegen J.C., Enquist B.J., Ferriere R. 2009. Advancing the metabolic
theory of biodiversity. Ecol. Lett. 12:1001–1015. SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY p
p
Rabosky D.L., Chang J., Title P.O., Cowman P.F., Sallan L., Friedman
M., Kaschner K., Garilao C., Near T.J., Coll M., Alfaro M.E. 2018. An inverse latitudinal gradient in speciation rate for marine fishes. Nature. 559:392–395. Stevens G.C. 1989. The latitudinal gradient in geographical range: how
so many species coexist in the Tropics. Am. Nat. 133:240–256. Rabosky D.L., Hurlbert A.H. 2015. Species richness at contin-
ental scales Is dominated by ecological limits. Am. Nat. 185:
572–583. Storch D., Bodhalkova E., Okie J. 2018. The more-individuals hypo-
thesis revisited?: the role of community abundance in species
richness regulation and the productivity – diversity relationship. Ecol. Lett. 21:920–937. Rabosky D.L., Matute D.R. 2013. Macroevolutionary speciation rates
are decoupled from the evolution of intrinsic reproductive isolation
in Drosophila and birds. Proc. Natl. Acad. Sci. U. S. A. 110:15354–
15359. Svetec N., Cridland J.M., Zhao L., Begun D.J. 2016. The adaptive
significance of natural genetic variation in the DNA damage
response of Drosophila melanogaster. PLoS Genet. 12:1–18. Rabosky D.L., Title P.O., Huang H. 2015. Minimal effects of latitude
on present-day speciation rates in New World birds. Proc. Biol. Sci. 282:20142889. p
Title P.O., Rabosky D.L. 2019. Tip rates, phylogenies and diversification:
what are we estimating, and how good are the estimates? Methods
Ecol. Evol. 10:821–834. Rangel T.F., Edwards N.R., Holden P.B., Diniz-Filho J.A.F., Gosling
W.D., Coelho M.T.P., Cassemiro F.A.S., Rahbek C., Colwell R.K. 2018. Modeling the ecology and evolution of biodiversity: Biogeograph-
ical cradles, museums, and graves. Science. 361:eaar5452. Tonini J.F.R., Beard K.H., Ferreira R.B., Jetz W., Pyron R.A. 2016. Fully-
sampled phylogenies of squamates reveal evolutionary patterns in
threat status. Biol. Conserv. 204:23–31. Upham N.S., Esselstyn J.A., Jetz W. 2019. Inferring the mammal tree:
species-level sets of phylogenies for questions in ecology, evolution,
and conservation. PLoS Biol. 17:e3000494. Redding D.W., Mooers A.Ø. 2006. Incorporating evolutionary meas-
ures into conservation prioritization. Conserv. Biol. 20:1670–1678. Valen L. 1973. A new evolutionary law. Evol. Theory. 1:1–
h b
d
l
h h Rensch B. 1959. Evolution above the species level. London (UK):
Methuen. Van Valen L. 1973. A new evolutionary law. Evol. Theory. 1:1 30. Viechtbauer W. 2010. Conducting meta-analyses in R with the metafor. J. Stat. Softw. 36:1–48. Ries G., Heller W., Puchta H., Sandermann H., Seidlitz H.K., Hohn B. 2000. Elevated UV-B radiation reduces genome stability in plants. Nature. 406:98–101. SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY
SKEELS ET AL.—EVOLUTIONARY SPEED AND TETRAPOD BIODIVERSITY Waide R.B., Willig M.R., Steiner C.F., Mittelbach G., Gough L., Dodson
S.I., Juday G.P., Parmenter R. 1999. The relationship between
productivity and species richness. Annu. Rev. Ecol. Syst. 30:257–300. Rohde K. 1992. Latitudinal gradients in species diversity: the search
for the primary cause. Oikos. 65:514–527. p
y
p
y
Weir J.T., Schluter D. 2008a. Calibrating the avian molecular clock. Mol. Ecol. 17:2321–2328. p
y
Rohde K. 1996. Rapoport’s rule is a local phenomenon and cannot
explain latitudinal gradients in species diversity. Biodivers. Lett. 3:10–13. Weir J.T., Schluter D. 2008b. The latitudinal gradient in recent
speciation and extinction rates of birds and mammals. Science. 319:1574–1576. Roll U., Feldman A., Novosolov M., Allison A., Bauer A.M., Bernard
R., Böhm M., Castro-Herrera F., Chirio L., Collen B., Colli G.R.,
Dabool L., Das I., Doan T.M., Grismer L.L., Hoogmoed M., Itescu
Y., Kraus F., Lebreton M., Lewin A., Martins M., Maza E., Meirte
D., Nagy Z.T., Nogueira C.D.C., Pauwels O.S.G., Pincheira-Donoso
D., Powney G.D., Sindaco R., Tallowin O.J.S., Torres-Carvajal O.,
Trape J.F., Vidan E., Uetz P., Wagner P., Wang Y., Orme C.D.L.,
Grenyer R., Meiri S. 2017. The global distribution of tetrapods
reveals a need for targeted reptile conservation. Nat. Ecol. Evol. 1:1677–1682. Wilman H., Belmaker J., Simpson J., de la Rosa C., Rivadeneira M.M.,
Jetz W. 2014. EltonTraits 1.0: species-level foraging attributes of the
world’s birds and mammals: ecological archives E095-178. Ecology. 95:2027. Woolfit M. 2009. Effective population size and the rate and pattern of
nucleotide substitutions. Biol. Lett. 5:417–420. Wright S.D., Gillman L.N., Ross H.A., Keeling D.J. 2010. Energy and the
tempo of evolution in amphibians. Glob. Ecol. Biogeogr. 19:733–740. Wright S.D., Ross H.A., Keeling D.J., McBride P., Gillman L.N. 2011. Thermal energy and the rate of genetic evolution in marine fishes. Evol. Ecol. 25:525–530. Rosenzweig M.L. 1995. Species diversity in space and time. Cambridge
(UK): Cambridge University Press.
|
https://openalex.org/W2081016978
|
https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0111312&type=printable
|
English
| null |
α-Mangostin Disrupts the Development of Streptococcus mutans Biofilms and Facilitates Its Mechanical Removal
|
PloS one
| 2,014
|
cc-by
| 9,946
|
Abstract This is an open-access article distributed under the terms of the Creative Commons Att
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability: The authors confirm that all data underlying the findings are fully available without restriction. All relevant data are within the paper and its
Supporting Information files. Funding: This work was supported by National Foundation for Science and Technology Development (Nafosted) grant (106.05-2011.44) to PTMN (http://www. nafosted.gov.vn); Vietnam Education Foundation (VEF) research scholar grant (VEF 2012) to PTMN (https://home.vef.gov); and National Institutes of Health (NIH)
grant (DE018023) to HK. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * Email: koohy@dental.upenn.edu (HK); phuong_nguyen_99@yahoo.com (PTMN) attributes that are associated with the establishment and mainte-
nance of cariogenic biofilms [5]. uyen1*, Megan L. Falsetta2, Geelsu Hwang3, Mireya Gonzalez-Begne2, Hyun Koo2,3 1 Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam, 2 Center for Oral Biology, University of Rochester Medical Center, Rochester,
New York, United States of America, 3 Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics, School of Dental Medicine, University of
Pennsylvania, Philadelphia, Pennsylvania, United States of America Abstract a-Mangostin (aMG) has been reported to be an effective antimicrobial agent against planktonic cells of Streptococcus
mutans, a biofilm-forming and acid-producing cariogenic organism. However, its anti-biofilm activity remains to be
determined. We examined whether aMG, a xanthone purified from Garcinia mangostana L grown in Vietnam, disrupts the
development, acidogenicity, and/or the mechanical stability of S. mutans biofilms. Treatment regimens simulating those
experienced clinically (twice-daily, 60 s exposure each) were used to assess the bioactivity of aMG using a saliva-coated
hydroxyapatite (sHA) biofilm model. Topical applications of early-formed biofilms with aMG (150 mM) effectively reduced
further biomass accumulation and disrupted the 3D architecture of S. mutans biofilms. Biofilms treated with aMG had lower
amounts of extracellular insoluble and intracellular iodophilic polysaccharides (30–45%) than those treated with vehicle
control (P,0.05), while the number of viable bacterial counts was unaffected. Furthermore, aMG treatments significantly
compromised the mechanical stability of the biofilm, facilitating its removal from the sHA surface when subjected to a
constant shear stress of 0.809 N/m2 (.3-fold biofilm detachment from sHA vs. vehicle-treated biofilms; P,0.05). Moreover,
acid production by S. mutans biofilms was disrupted following aMG treatments (vs. vehicle-control, P,0.05). The activity of
enzymes associated with glucan synthesis, acid production, and acid tolerance (glucosyltransferases B and C,
phosphotransferase-PTS system, and F1F0-ATPase) were significantly inhibited by aMG. The expression of manL, encoding
a key component of the mannose PTS, and gtfB were slightly repressed by aMG treatment (P,0.05), while the expression of
atpD (encoding F-ATPase) and gtfC genes was unaffected. Hence, this study reveals that brief exposures to aMG can disrupt
the development and structural integrity of S. mutans biofilms, at least in part via inhibition of key enzymatic systems
associated with exopolysaccharide synthesis and acidogenicity. aMG could be an effective anti-virulence additive for the
control and/or removal of cariogenic biofilms. Editor: Jens Kreth, University of Oklahoma Health Sciences Center, United States of America Received July 7, 2014; Accepted September 19, 2014; Published October 28, 2014 uyen et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
tion, and reproduction in any medium, provided the original author and source are credited. Copyright: 2014 Nguyen et al. This is an open-access article distributed under the terms of the Creative Commons Attribut
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Copyright: 2014 Nguyen et al. October 2014 | Volume 9 | Issue 10 | e111312 PLOS ONE | www.plosone.org Preparation and treatment of the biofilm S. mutans UA159 (ATCC 700610), a proven virulent-cariogenic
strain selected for genomic sequencing, was used in this study. Biofilms of S. mutans were formed on saliva coated hydroxyapatite
(sHA) surfaces (12.7 mm in diameter, 1 mm in thickness, Clarkson
Chromatography Products Inc., South Williamsport, PA), as
previously described [28]. The biofilms were grown in ultra-
filtered (10 kDa MW cut-off membrane; Prep/Scale, Millipore,
MA)
buffered
tryptone-yeast
extract
broth
(UFTYE;
2.5%
tryptone and 1.5% yeast extract with the addition of 4.35 g/L
of potassium phosphate and 1 g/L of MgSO4?7H2O, pH 7.0) with
1% sucrose at 37uC and 5% CO2. Briefly, S. mutans cells in
exponential growth phase were inoculated into UFTYE and
applied to wells containing sHA discs placed vertically in a custom-
made holder. Biofilms were allowed to form on sHA discs and
were treated for the first time with the test agents or vehicle control
after 6 h of development. Subsequently, the biofilms were treated
at 8 am (20 h-old) and 6 pm (30 h-old), with two more additional
treatments the following day (8 am; 44 h-old and 6 pm; 54 h-old). The biofilms were exposed to the treatments for 60 s, dip-washed
in sterile saline solution (0.89% w/v NaCl) to remove excess
agents, and then transferred to fresh culture medium [29,30]. The
biofilm was analyzed after 44 h and 68 h using confocal
microscopy to examine the effects on the overall 3D architecture
after receiving the initial topical treatments (Figure 2). At 68 h, the
biofilms were removed, homogenized and subjected to biochem-
ical analysis as detailed previously [28]. Briefly, biomass was
assessed with an aliquot of the homogenized suspension centri-
fuged at 10,000 g for 10 min at 4uC, and the cell pellet was
washed twice with water, then dried in the dry oven at 105uC for
24 h and weighed [28]. The water soluble and insoluble
exopolysaccharides (EPS), and intracellular iodophilic polysaccha-
rides (IPS) were extracted and quantified via colorimetric assays
[28]. The total number of viable cells in each of the biofilms was
determined by counting colony forming units (CFU), while total
protein was quantified via ninhydrin assays as descrbed in Koo et
al. [28]. Furthermore, the pH of the culture media of treated and
untreated biofilms was monitored every 2 hours with an Orion pH
electrode attached to an Orion 290 A+ pH meter (Thermo Fisher
Scientific). Introduction Partially purified
aMG was recovered from the active fractions and then further
separated by silica gel column chromatography (Merck Kieselgel
60, 70–230 mesh) and eluting with n-hexane – chloroform – ethyl
acetate – methanol (4:1:0.5:0.3, by volume), yielding a single
compound, aMG, as yellow crystals. The purity of aMG was
examined by high-pressure liquid chromatography connected with
mass spectrometry (LCMSD- Trap-SL Mass spectra, Agilent
1100, Palo Alto, California). The chemical structure (Fig. 1) of
aMG was determined using nuclear magnetic resonance (Bruker
Avance 500 spectrometer, Germany). EPS synthesis via S. mutans-derived Gtfs is critical for
cariogenic biofilm formation, since the glucans produced by the
secreted exoenzymes (present in the pellicle-coated tooth and on
bacterial surfaces) promote local bacterial accumulation, while
embedding bacteria in a diffusion-limiting matrix. These processes
create highly cohesive and adhesive biofilms that are firmly
attached to surfaces and are difficult to remove [15–18]. At the
same time, the EPS-rich matrix shelters resident organisms from
antimicrobial and other inimical influences [18–20]. In parallel,
sugars (in addition to sucrose) are fermented by S. mutans and
other acidogenic bacteria ensnared within the biofilm matrix,
creating acidic microenvironments across the three-dimensional
(3D) architecture and at the surface of attachment [18,21,22]. Acidification of the milieu favors growth of aciduric organisms,
further enhancing EPS production and ensuring biofilm accrual
and localized acid-dissolution of the enamel in areas where biofilm
is present and pH is low [18,23]. Therefore, using bioactive agents
that target EPS-mediated biofilm assembly and acidogenicity
could disrupt the pathogenesis of dental caries in a highly effective
and precise manner. The compound at concentration of 100, 150 and 200 mM was
dissolved in 25% ethanol, which was also used as a vehicle control;
treatments with 25% ethanol did not affect the viability of cells of
S. mutans in a biofilm when compared to untreated controls. The
pH of the treatment solution was maintained at 5.860.2, based on
the observation that aMG activity is best at acidic pH [27]. Plants are valuable sources of new bioactive compounds to
combat dental caries, because they produce a wide variety of
secondary metabolites, many of which have been found to have
biological properties against oral pathogens in vitro (as reviewed in
Jeon et al. [5]). Garcinia mangostana L. (Guttiferae) is a widely
cultivated fruit tree in Southeast Asian nations, including Thai-
land, Sri Lanka, The Philippines, and Vietnam [24]. The pericarp
of G. Introduction Many infectious diseases in human are caused by virulent
biofilms, including oral diseases [1]. Among them, dental caries
continues to be one of the most ubiquitous and costly biofilm-
dependent diseases throughout the world [2,3]. For organisms
associated
with
caries
development,
the
production
of
an
extracellular polysaccharide (EPS)-rich biofilm matrix, acidifica-
tion of the milieu, and the maintenance of acidic pH microen-
vironment in close proximity to the tooth enamel are major
controlling virulence factors linked with the pathogenesis of the
disease. Current therapeutic approaches to control pathogenic oral
biofilms fall short; the search for new/improved agents may lead
to more efficacious anti-caries therapies [4–6]. Natural products
are currently regarded as potentially promising sources for new
bioactive agents that may function to suppress these key virulence The assembly of cariogenic biofilms results from complex
interactions that occur between specific oral bacteria, the products
they produce, host saliva and dietary carbohydrates, all of which
occurs on pellicle-coated tooth surfaces [7,8]. Streptococcus mutans
has been recognized as one of the key etiologic agents associated
with the initiation of dental caries, although additional organisms
may contribute to its pathogenesis [9]. Sucrose is considered the
primary catalyst for caries development, as it serves as a substrate
for the production of both EPS and acids. S. mutans can effectively
form cariogenic biofilms when sucrose is available, because this
bacterium rapidly synthesizes EPS (from sucrose) through the
activity of exoenzymes (e.g. glucosyltransferases; Gtfs) [8]. At the
same time, S. mutans produces acid and is highly aciduric,
allowing it to tolerate and continue to produce acids in low pH October 2014 | Volume 9 | Issue 10 | e111312 1 PLOS ONE | www.plosone.org PLOS ONE | www.plosone.org a-Mangostin Affects Biofilm Formation by Streptococcus mutans microenvironments, while readily adapting to acidic and other
environmental stresses [10–14]. Kieselgel 60, 70–230 mesh) by eluting with n-hexane – ethyl
acetate – methanol (6:3:0.1, by volume) and 10 mL volumes of
eluant were collected in test tubes. The aliquots of each fraction
were subjected to thin-layer chromatography (60 F254, 1 mm
plate, Merck) in a solvent system containing toluene – ethyl acetate
– acetone – formic acid (5:3:1:1, by volume). Preparation and treatment of the biofilm Our previous work showed that aMG exhibits antimicrobial
activity against planktonic S. mutans cells via multiple actions,
particularly reducing acid production by disrupting the membrane
of this organism [27]. However, the question as to whether this
agent is capable of compromising the ability of S. mutans to
develop biofilms using a clinically relevant treatment regiment
(brief topical exposures) remains to be elucidated. Therefore, the
aim of the present study was to investigate the potential
effectiveness of topical applications of aMG and its biological
actions against S. mutans biofilm formation on saliva-coated
apatitic surfaces. Introduction mangostana has been used in traditional medicine to treat a
variety of infections. Experimental studies have demonstrated that
xanthone derivatives are the major bioactive substances, exhibiting
antioxidant, antitumor, anti-inflammatory, and antimicrobial
activities [24–26]. Materials and Methods Extraction and isolation of a-mangostin Extraction and isolation of a-mangostin g
Garcinia mangostana L is a fruit plant widely available in the
south of Vietnam. The dried powder of samples of Garcinia
mangostana peels collected from Binhduong province (south of
Vietnam) was used in this study. No specific permission for
collection of G. mangostana is required for this location because it
is not an endangered or protected species. Ethanolic extracts of G. mangostana were prepared for the initial step of aMG isolation. The dried powder of G. mangostana peels collected from the
South
of
Vietnam
were
extracted
with
ethanol
at
room
temperature, followed by an evaporation of solvent to give a dark
brown gummy residue. This residue was taken up in water
followed by extraction with n-hexane to produce the most
bioactive fractions. The n-hexane fraction was then evaporated
and dried under reduced pressure. Further separation was
performed using silica gel column chromatography (Merck October 2014 | Volume 9 | Issue 10 | e111312 2 PLOS ONE | www.plosone.org a-Mangostin Affects Biofilm Formation by Streptococcus mutans Figure 1. Chemical structure for aMG. Molecular formula: C24H26O6. Molecular weight: 410.466. doi:10.1371/journal.pone.0111312.g001
g
y
p Figure 1. Chemical structure for aMG. Molecular formula: C24H26O6. Molecular weight: 410.466. doi:10.1371/journal.pone.0111312.g001 Confocal microscopy of biofilms sectioning at each of these positions. Three independent exper-
iments were conducted. The step size of z-series scanning was
2 mm. The confocal images were analyzed using software for
simultaneous visualization of EPS and bacterial cells within intact
biofilms [18,31,32]. Amira 5.4.1 software (Visage Imaging, San
Diego, CA) was used to create 3D renderings of each structural
component (EPS and bacteria) to examine the architecture of the
biofilm. The overall effect of topical applications of aMG on the 3D
architecture and the spatial distribution of EPS and bacterial
biomass within intact biofilms was assessed using confocal
fluorescence imaging [18]. Briefly, 2.5 mM Alexa Fluor 647-
labeled dextran conjugate (10,000 MW; absorbance/fluorescence
emission maxima 647/668 nm; Molecular Probes Inc., Eugene,
OR) was added to the culture medium during the formation and
development of S. mutans biofilms. The fluorescently-labeled
dextran serves as a primer for Gtf-mediated glucan synthesis and
can be simultaneously incorporated during EPS matrix synthesis
over the course of biofilm development, but does not stain the
bacterial cells at the concentrations used in the study. The
bacterial cells in the biofilms were labeled with 2.5 mM SYTO 9
green-fluorescent nucleic acid stain (480/500 nm; Molecular
Probes Inc., Eugene, OR) using standard procedures [18]. Laser
scanning confocal fluorescence imaging of the biofilms was
performed using an Olympus FV 1000 two-photon laser scanning
microscope (Olympus, Tokyo, Japan) equipped with a 10 X (0.45
numerical aperture) water immersion objective lens. Each biofilm
was scanned at 5 randomly selected positions on the microscope
stage and the confocal image series were generated by optical F-ATPase and phosphotransferase system (PTS) assays In the present study, different bioinformatics tools and databases
were used. The crystal structure of glucosyltransferases C (GtfC)
from the dental caries pathogen Streptococcus mutans is available
in the Protein Data Bank (PDB) and was used as a receptor for
docking of the aMG compound (ligand) using HEX software. Since the crystal structure of GtfB is not yet available, Phyre server
[33] was used to predict ligand sites. HEX has been reported as an
interactive molecular graphic program. It calculates protein-ligand
docking, assuming that the ligand is rigid and then superimposes
pairs of molecules using only their 3D shapes [34,35]. In addition,
it uses Spherical Polar Fourier (SPF) correlations, increasing the
speed of the calculations, and it also has integrated graphics
software to view the final result [35–38]. PDB was used to
download the crystal structure of glucansucrase from the dental
caries pathogen Streptococcus mutans (http://www.rcsb.org/pdb/
home/home.do). PubChem Compound was used for retrieving
the 3D-structure of a-mangostin (http://www.ncbi.nlm.nih.gov/
pccompound). MarvinSketch software was utilized for obtaining
the a-mangostin structure in a PDB format (http://www. chemaxon.com/products/marvin/marvinsketch/), and the Hex-
Server (HEX 6.9 software) was accessed for calculating and
displaying protein-ligand docking (http://hexserver.loria.fr/). The
parameters used for docking included: Correlation type (Shape
only), FFT mode (3D fast life), Grid dimension (0.6), Receptor
range (180), Ligand range (180), Twist range (360), and Distance
range (40) were used. F-ATPase and phosphotransferase system (PTS) assays
F-ATPase and PTS activity of treated biofilm cells were
determined as described by Belli and Marquis [39] and Phan et
al. [40]. Biofilms were homogenized and centrifuged at 4uC, and
then biofilm pellets from each sample were resuspended in 2.5 ml
of 75 mM Tris-HCl buffer (pH 7.0) with 10 mM MgSO4. Toluene (250 ul) was added to each biofilm cell suspension prior
to vigorous vortex mixing and incubation for 5 min at 37uC. Each
suspension was then subjected to two cycles of freezing in a dry ice-
ethanol bath and thawing at 37uC. Permeabilized biofilm cells
were harvested by centrifugation. They were then resuspended in
1.0 ml of 75 mM Tris-HCl buffer (pH 7.0) with 10 mM MgSO4. The suspension was quickly frozen in a dry ice-ethanol bath and
stored at 270uC for F-ATPase and PTS assays. F-ATPase activity
was determined as described by Belli and Marquis [39]. The F-
ATPase reaction is initiated by the addition of 30 ml of 0.5 M ATP
(pH 6.0). Determination of mechanical stability of biofilms The mechanical stability of the biofilms treated with or without
aMG was compared using a custom built device (detailed
information is in Figure S1). Biofilms were exposed to constant
shear stress of 0.809 N/m2 for 10 min, which is capable of
removing S. mutans biofilm from sHA surface; such shear stress
was determined as a threshold for .50% removal of untreated S. mutans biofilms from saliva-coated HA surfaces using our model. Shear stress at the biofilm surface was produced by shear flow
generated via rotating paddle, and estimated based on Reynolds
number of the flow (turbulent flow) and the surface friction using
Blasius formula (Supplemental information). The amount of
biofilm dry-weight (biomass) before and after application of shear Figure 2. The experimental design for the treatment and analysis of biofilms of S. mutans. The clinical conditions of typical exposure of
exogenously introduced therapeutic agents in the mouth were simulated by applying the test agent twice daily for brief exposures (60 s) at early/
initial formation of the biofilm (6 h). Subsequently, the biofilms were treated twice at 8 am (20 h-old) and 6 pm (30 h-old) with two more additional
treatments the following day (8 am; 44 h-old and 6 pm; 54 h-old). doi:10.1371/journal.pone.0111312.g002 Figure 2. The experimental design for the treatment and analysis of biofilms of S. mutans. The clinical conditions of typical exposure of
exogenously introduced therapeutic agents in the mouth were simulated by applying the test agent twice daily for brief exposures (60 s) at early/
initial formation of the biofilm (6 h). Subsequently, the biofilms were treated twice at 8 am (20 h-old) and 6 pm (30 h-old) with two more additional
treatments the following day (8 am; 44 h-old and 6 pm; 54 h-old). doi:10.1371/journal.pone.0111312.g002 October 2014 | Volume 9 | Issue 10 | e111312 October 2014 | Volume 9 | Issue 10 | e111312 PLOS ONE | www.plosone.org 3 a-Mangostin Affects Biofilm Formation by Streptococcus mutans Table 1. Streptococcus mutans UA159 biofilm composition after treatments with 150 mM aMG. Table 1. Streptococcus mutans UA159 biofilm composition after treatments with 150 mM aMG. Biofilm composition
Vehicle
150 mM aMG
Dry weight (mg/biofilm)
4.7360.41
3.0060.45*
Protein (mg/biofilm)
2.8560.38
1.6760.19*
Soluble EPS (mg/biofilm)
326.6637.2
229.7691.0
Insoluble EPS (mg/biofilm)
1112.16151.7
356.9649.0*
IPS (mg/biofilm)
188.3617.8
79.9622.6*
CFU/biofilm
2.77E+0865.98E+07
2.25E+0865.50E+07
Data are expressed as the mean 6 one standard deviation. Determination of mechanical stability of biofilms For each parameter, values marked with an asterisk are significantly different from that for the vehicle control
(n = 8; P,0.05, pair-wise comparison using Student’s t test). doi:10.1371/journal.pone.0111312.t001 Data are expressed as the mean 6 one standard deviation. For each parameter, values marked with an asterisk are significantly different from that for the vehicle control
(n = 8; P,0.05, pair-wise comparison using Student’s t test). doi:10.1371/journal.pone.0111312.t001 stress
for
each
condition
(vehicle-
and
aMG-treated)
was
determined. Then, the percentage of biofilm that remained on
sHA disc surface was calculated. All experiments were performed
in quadruplicates in three distinct experiments. control, the same reaction was carried out with 25% ethanol (v/v)
replacing the test agent solutions. Glucosyltransferase activity was
measured by incorporation of [U-14C-glucose] from labeled
sucrose into glucans [34]. The radiolabelled glucans were
quantified by scintillation counting. Reverse transcription quantitative PCR (RT-qPCR)
RT qPCR was performed to evaluate the expression Reverse transcription quantitative PCR (RT-qPCR)
RT-qPCR was performed to evaluate the expression of the
gtfB, gtfC, atpD, and manL genes. Biofilms were treated as
described in the Figure 2. RNA was extracted and purified using
standard protocols optimized for biofilms [41]. The RNA integrity
numbers (RIN) of purified samples used for RT-qPCR were
determined by microcapillary electrophoresis on an Agilent 2100
Bioanalyzer (Agilent Technologies, Santa Clara, CA). Purified
RNA samples (RIN$9) were stored in RNase-free water at 2
80uC. cDNAs were synthesized from 1 mg of purified RNA using a
BioRad iScript cDNA synthesis kit (Bio-Rad Laboratories, Inc.,
Hercules, CA). RNA samples without reverse transcriptase were
included as a negative control. The resulting cDNAs and negative
controls were amplified by a MyiQ qPCR detection system with
iQ SYBR Green supermix (Bio-Rad Laboratories, Inc., CA, USA)
and specific primers. When Taqman probes were available,
cDNAs and controls were amplified using a Bio-Rad CFX96 F-ATPase and phosphotransferase system (PTS) assays Samples of 50 ml were removed and assayed for
inorganic phosphate liberated from cleavage of ATP with reagents
from American Monitor Co. (Indianapolis, IN) [39]. Phospho-
transferase system (PTS) activity was assessed in terms of pyruvate
production from phosphoenolpyruvate in response to glucose
addition. Pyruvate was assayed by use of lactic dehydrogenase and
measurements of the change in absorbance of 340 nm light
associated with oxidation of NADH [39]. Determination of Gtf activity y
GtfB and GtfC were obtained from recombinant strains
carrying the appropriate genes as detailed elsewhere [34]. Strain
S. milleri KSB8 harboring the gtfB gene transformed from S. mutans GS-5 and S. mutans WHB 410 construct expressing gtfC
gene only were used. The GtfB and GtfC enzymes (E.C. 2.4.1.5)
were prepared from culture supernatants and purified to near
homogeneity by hydroxyapatite column chromatography. The
purified Gtfs (1–1.5 U) were mixed with the test compound and
incubated with a [U-14C-glucose]-sucrose substrate (0.2 mCi/ml;
200.0 mmol of sucrose per liter, 40 mmol of dextran 9000 per liter,
and 0.02% sodium azide in adsorption buffer consisting of 50 mM
KCl, 1.0 mM KPO4, 1.0 mM CaCl2, and 0.1 mM MgCl2,
pH 6.5) to a final concentration of 100 mmol of sucrose per liter
(200 ml final volume) at 37uC with rocking for 4 h. For the vehicle- October 2014 | Volume 9 | Issue 10 | e111312 PLOS ONE | www.plosone.org 4 a-Mangostin Affects Biofilm Formation by Streptococcus mutans Figure 3. Representative 3D rendered images of 44 h and 68 h-old S. mutans biofilms following topical treatments. Biofilms we
reated with the vehicle control in panel A and with 150 mM aMG in panel B. The EPS channel is in red, while bacterial cells are in green. Sca
bars = 100 mm. Biofilms were formed on hydroxyapatite discs (sHA) in the presence of 1% (wt/vol) sucrose, and treated with test agents twice da
doi:10.1371/journal.pone.0111312.g003 Figure 3. Representative 3D rendered images of 44 h and 68 h-old S. mutans biofilms following topical treatments. Biofilms were
treated with the vehicle control in panel A and with 150 mM aMG in panel B. The EPS channel is in red, while bacterial cells are in green. Scale
bars = 100 mm. Biofilms were formed on hydroxyapatite discs (sHA) in the presence of 1% (wt/vol) sucrose, and treated with test agents twice daily. doi:10.1371/journal.pone.0111312.g003 MIQE guidelines [44] were followed for quality control of the data
generated and for data analysis. The gene expression profile was
determined 4 h after the topical treatment at 20 h (Figure 2), to
evaluate the impact of aMG on S. mutans within the accumulated
biofilms post-treatment. This time point represents the most active
period of the biofilm development using our model, and was
selected based on our biochemical data and previous studies on the
dynamics of the S. Determination of Gtf activity mutans transcriptome during biofilm formation
on sHA and in response to topically applied agents [43,45]. system (Bio-Rad Laboratories). The 16S rRNA primers/TaqMan
probes were run separately, and primers/TaqMan probes for
other specific targets were combined and used in a multiplex
setting. For reactions with only one TaqMan probe (used for target
16S rRNA), the iQ Supermix (BioRad) was used. For multiplex
reactions (gtfB, gtfC) and (atpD, manL) the iQ Multiplex
Powermix (BioRad) were employed. Standard curves were used
to determine the relative number of cDNA molecules, which were
normalized to the relative number of 16S rRNA cDNA in each
sample, as described previously [42]. 16S rRNA served as a
reference gene [43]. These values were used to determine the fold-
change between each treated sample and the vehicle control. The MIQE guidelines [44] were followed for quality control of the data
generated and for data analysis. The gene expression profile was
determined 4 h after the topical treatment at 20 h (Figure 2), to
evaluate the impact of aMG on S. mutans within the accumulated
biofilms post-treatment. This time point represents the most active
period of the biofilm development using our model, and was
selected based on our biochemical data and previous studies on the
dynamics of the S. mutans transcriptome during biofilm formation
on sHA and in response to topically applied agents [43,45]. October 2014 | Volume 9 | Issue 10 | e111312 PLOS ONE | www.plosone.org 5 PLOS ONE | www.plosone.org a-Mangostin Affects Biofilm Formation by Streptococcus mutans m mechanical stability following topical treatments. Panel A depicts the percentage of biomass of vehicle
ained on sHA after exposure to shear stress. The amount of biofilm dry-weight (biomass) before and after applicat
n (vehicle- and aMG-treated) was determined, and the percentage of biofilm that remained on sHA disc surface wa
w.plosone.org
6
October 2014 | Volume 9 | Iss film mechanical stability following topical treatments. Panel A depicts the percentage of biomass of vehicl
emained on sHA after exposure to shear stress. The amount of biofilm dry-weight (biomass) before and after applicat
tion (vehicle- and aMG-treated) was determined, and the percentage of biofilm that remained on sHA disc surface wa Figure 4. Biofilm mechanical stability following topical treatments. Panel A depicts the percentage of biomass of vehicle- or aMG-treated
biofilms that remained on sHA after exposure to shear stress. Determination of Gtf activity The amount of biofilm dry-weight (biomass) before and after application of shear stress
for each condition (vehicle- and aMG-treated) was determined, and the percentage of biofilm that remained on sHA disc surface was calculated. Data Figure 4. Biofilm mechanical stability following topical treatments. Panel A depicts the percentage of biomass of vehicle- or aMG-treated
biofilms that remained on sHA after exposure to shear stress. The amount of biofilm dry-weight (biomass) before and after application of shear stress
for each condition (vehicle- and aMG-treated) was determined, and the percentage of biofilm that remained on sHA disc surface was calculated. Data October 2014 | Volume 9 | Issue 10 | e111312 PLOS ONE | www.plosone.org PLOS ONE | www.plosone.org 6 are expressed as the mean 6 one standard deviation. Values are significantly different from that for the vehicle control (n = 12; P,0.05, pair-wise
comparison using Student’s t test). Panel B shows representative 3D rendered images of treated-biofilms of S. mutans after shearing. The EPS channel
is in red, and the bacterial cells are in green. Scale bars = 100 mm. doi:10.1371/journal.pone.0111312.g004
a-Mangostin Affects Biofilm Formation by Streptococcus mutans a-Mangostin Affects Biofilm Formation by Streptococcus mutans a-Mangostin Affects Biofilm Formation by Streptococcus mutans are expressed as the mean 6 one standard deviation. Values are significantly different from that for the vehicle control (n = 12; P,0.05, pair-wise
comparison using Student’s t test). Panel B shows representative 3D rendered images of treated-biofilms of S. mutans after shearing. The EPS channel
is in red, and the bacterial cells are in green. Scale bars = 100 mm. doi:10.1371/journal.pone.0111312.g004 doi:10.1371/journal.pone.0111312.g004
Figure 5. Snapshot of glucosyltransferase interaction with aMG compound and influence of 150 mM aMG on the activities of Gt
and GtfC. Panel A depicts the ribbon model of glucosyltransferase C (brown) docking a-mangostin (blue) using HEX-docking software Amino acid
uch as Trp 517, Glu 515, Asp 588 and Asn 481 are interacting in the glucosyl binding site. Panel B depicts the surface model of glucosyltransferase
docking a-mangostin (red) and acarbose (purple) using HEX-docking software. Panel C depicts the glucosyltransferase B 3D ligand-binding si
predicted model using Phyre Server. Panel D depicts Gtf activity of S. mutans cells when treated with aMG. The percentage of inhibition w
calculated setting the vehicle control to 100% Gtf activity. Data are expressed as the mean 6 one standard deviation. aMG disrupts the accumulation and acidogenicity of S.
mutans biofilms Altogether, the biochemical changes inflicted by aMG may
affect the matrix assembly and 3D biofilm architecture, which
could disrupt the mechanical stability and adhesive strength of the
treated biofilms. In our experiment, S. mutans biofilms were initially treated with
a-mangostin (aMG) at concentrations of 100, 150, and 200 mM
(Table S1) based on bioactivity against planktonic S. mutans cells
[27] and solubility in the vehicle system. We selected a
concentration of 150 mM aMG, because it was as effective as
200 mM in reducing the overall biofilm development and acid
production. Statistical analyses Data are presented as the mean 6 one standard deviation (SD). Pair-wise comparisons were made between test and control using
Student’s t-test. Statistical analysis was performed using JMP
(version 3.1; SAS Institute, Cary, NC). The level of significance
was set at 5%. Figure 6. Effects of aMG on acid production by S. mutans UA159. Vehicle is represented by (&), while 150 mM aMG is represented by (m). Data are expressed as the mean 6 one standard deviation for experiments run in triplicates in at least three separate experiments. doi:10.1371/journal.pone.0111312.g006 Figure 6. Effects of aMG on acid production by S. mutans UA159. Vehicle is represented by (&), while 150 mM aMG is represented by (m). Data are expressed as the mean 6 one standard deviation for experiments run in triplicates in at least three separate experiments. doi:10.1371/journal.pone.0111312.g006 The amount of insoluble exopolysaccharides (EPS) was drastically
reduced, while the soluble EPS content was unaffected by aMG
treatments. The data suggest that GtfB and GtfC, which are
largely responsible for the synthesis of insoluble glucans in the
biofilm matrix [8], could be targeted by aMG; while possibly
having limited effects on the activity of GtfD (involved for soluble
glucan
synthesis). Interestingly,
the amount
of intracellular
iodophilic polysaccharides (IPS), a glycogen-like storage polymer
[46], was significantly disrupted by treatments with the agent. Determination of Gtf activity Values are significantly differe
rom that for the vehicle control (n = 12; P,0.05, pair-wise comparison using Student’s t test). doi:10.1371/journal.pone.0111312.g005
P OS O
|
l
O
b
|
l
|
| Figure 5. Snapshot of glucosyltransferase interaction with aMG compound and influence of 150 mM aMG on the activities of GtfB
and GtfC. Panel A depicts the ribbon model of glucosyltransferase C (brown) docking a-mangostin (blue) using HEX-docking software Amino acids,
such as Trp 517, Glu 515, Asp 588 and Asn 481 are interacting in the glucosyl binding site. Panel B depicts the surface model of glucosyltransferase C
docking a-mangostin (red) and acarbose (purple) using HEX-docking software. Panel C depicts the glucosyltransferase B 3D ligand-binding site
predicted model using Phyre Server. Panel D depicts Gtf activity of S. mutans cells when treated with aMG. The percentage of inhibition was
calculated setting the vehicle control to 100% Gtf activity. Data are expressed as the mean 6 one standard deviation. Values are significantly different
from that for the vehicle control (n = 12; P,0.05, pair-wise comparison using Student’s t test). doi:10.1371/journal.pone.0111312.g005 October 2014 | Volume 9 | Issue 10 | e111312 7 PLOS ONE | www.plosone.org Figure 6. Effects of aMG on acid production by S. mutans UA159. Vehicle is represented by (&), while 150 mM aMG is represented by (m). Data are expressed as the mean 6 one standard deviation for experiments run in triplicates in at least three separate experiments. doi:10.1371/journal.pone.0111312.g006
a-Mangostin Affects Biofilm Formation by Streptococcus mutans a-Mangostin Affects Biofilm Formation by Streptococcus mutans aMG compromises the 3D architecture and mechanical
stability of S. mutans biofilms Confocal
images
revealed
a
marked
impairment
in the
development of an insoluble EPS-matrix (in red), as well as the
defective formation of bacterial clusters or microcolonies (in green)
following aMG treatment, particularly at 44 h (Figure 3). The few
microcolonies detected in the aMG-treated biofilms at 44 h
visually appear to be larger than those treated with vehicle-control,
suggesting that microcolony development was not completely
inhibited. Nevertheless, the defective biofilm assembly resulted in
an altered 3D architecture (at 68 h) characterized by sparsely
distributed microcolonies (with many areas on the sHA surface The data in Table 1 indicate that treatments with 150 mM
aMG significantly reduced the accumulation of S. mutans biofilms
on saliva-coated apatitic surfaces, which resulted in less biomass
(dry-weight) and less total protein compared to the vehicle control
(P,0.05). The viability of the biofilms was not significantly
impacted by the treatments. Nevertheless, short-term topical
applications
(one-minute
exposure,
twice
daily)
significantly
reduced the amount of polysaccharides in the biofilms (Table 1). October 2014 | Volume 9 | Issue 10 | e111312 PLOS ONE | www.plosone.org 8 a-Mangostin Affects Biofilm Formation by Streptococcus mutans Figure 7. Effects of aMG on ATPase and PTS activities of S. mutans UA159. The percentage of inhibition was calculated setting the vehicle
control to 100% enzymatic activity. Data are expressed as the mean 6 one standard deviation. Values are significantly different from that for the
vehicle control (n = 9; P,0.05, pair-wise comparison using Student’s t test). doi:10.1371/journal.pone.0111312.g007 Figure 7. Effects of aMG on ATPase and PTS activities of S. mutans UA159. The percentage of inhibition was calculated setting the vehicle
control to 100% enzymatic activity. Data are expressed as the mean 6 one standard deviation. Values are significantly different from that for the
vehicle control (n = 9; P,0.05, pair-wise comparison using Student’s t test). doi:10.1371/journal.pone.0111312.g007 that were devoid of such structures), as well as a less developed
EPS matrix, compared to vehicle-treated biofilms. These findings
agree well with our biochemical data showing a significant
reduction in the insoluble EPS content. ment of multi-microcolony aggregates via EPS-cell adhesions
provides structural integrity to S. mutans biofilms [16,18]. Thus,
we hypothesized that the disruptive effects of aMG could facilitate
biofilm removal and/or detachment. We investigated the impact
of aMG on mechanical stability of S. mutans biofilms using a
custom-built shear-inducing device (Figure S1). aMG inhibits GtfB and GtfC activity Previous studies have shown that extracellular glucans produced
by GtfB and GtfC enzymes play vital, yet distinct roles in the
formation
of
cariogenic
biofilms
and
are
essential
in
the
pathogenesis of dental caries (as reviewed in Bowen and Koo
[8]). The glucans synthesized by GtfC assemble the initial EPS
layers on the sHA surface, which provide enhanced binding sites
for S. mutans colonization and accumulation [52,53]. Conversely,
the highly insoluble and structurally rigid glucans formed by GtfB
embed the cells, contributing to the scaffolding of the 3D EPS-rich
matrix [18]. The accumulation of Gtf-derived EPS and bacteria
cells mediates the construction of EPS-enmeshed microcolonies
that are firmly anchored to the apatitic surface [16–18,54]. Here,
we examined whether aMG is capable of inhibiting the activity of
purified GtfB and GtfC enzymes, which could explain the
defective assembly and attachment of the treated biofilms observed
in this study. Since there is no previous data on Gtf inhibition by
aMG, we initially examined the likelihood of the agent to bind
Gtfs using in silico docking studies. A previous study has shown that aMG was particularly effective
in inhibiting the activity of F(H+)-ATPase and PTS [27], which are
critical for acid production and acid-tolerance and to ensure the
optimum function of glycolysis by S. mutans within biofilms [61]. However, the assays were conducted with S. mutans grown in the
planktonic phase. In this study, we examined the F-ATPase and
PTS activity of biofilm cells following the treatment with aMG. The membrane-bound F-ATPase (H+-translocating ATPase) is
considered the primary determinant for acid tolerance [61]. During glycolysis, protons are pumped out of the cell by F-ATPase
to help maintain DpH across the cell membrane, preventing
acidification of the cytoplasm, which would typically inhibit
intracellular enzymes [39]. Furthermore, under certain conditions,
it also generates ATP for S. mutans growth and persistence [62]. The data in Figure 7 show that the F-ATPase activity was strongly
inhibited by aMG with nearly 80% inhibition following topical
treatments. Docking studies support the prediction of conformation and
binding affinity for selected molecules against a given target
protein [55]. Therefore, docking of aMG on Gtf was carried out to
explore if/how this compound might interact with the enzymes. In
our study, when the GtfC enzyme was docked with aMG, the
energy value obtained by HEX software was 2511.36 Kcal/mol,
indicating a stable and strong binding between the two molecules
[55]. a-Mangostin Affects Biofilm Formation by Streptococcus mutans were more effectively removed from the sHA surface (84.51%
removal) than those treated with vehicle-control (49.2%; P,0.05)
when subjected to shear stress, indicating that the mechanical
stability of the biofilms was compromised by aMG. Indeed,
confocal images of aMG-treated biofilms show that most of the
bacterial biomass and EPS was removed, while vehicle-treated
biofilms show numerous EPS-enmeshed bacterial microcolonies
still attached on the sHA surface (Figure 4B). Clearly, the data
demonstrate that alterations in the EPS-matrix and microcolony
assembly resulted in significantly less adherent biofilms, which
facilitated their mechanical clearance from the sHA surface when
exposed to shear force. By reducing the production of insoluble
EPS, aMG treatments could affect optimal microcolony formation
and surface anchoring as well as the cell-matrix cross-linking forces
and the overall viscoelasticity, which have been shown to be
critical for weakening the biofilm structure [18,49,51]. Further
studies shall elucidate how aMG affects the adhesion forces and
rheological properties of the biofilms locally. that the function of these enzymes could be affected by aMG. Indeed, the enzymatic activity of purified GtfB and GtfC was
impacted by aMG as shown in Figure 5D. The test agent was
highly effective in reducing glucan synthesis by both enzymes,
displaying more than 70% inhibition (vs. vehicle control) at
150 mM, which agrees well with the in silico analysis, as well as the
biochemical (reduction of insoluble EPS content) and confocal
imaging (defective assembly of EPS-matrix and impaired micro-
colony formation) data of the aMG-treated biofilms. aMG inhibits GtfB and GtfC activity The best docked structure, visualized by UCSF Chimera
molecular modeling system version 1.8 (http://www.cgl.ucsf.edu/
chimera/download.html), showed the interaction of four amino
acids (Trp 517, Glu 515, Asp 588 and Asn 481) (Figure 5A and
5B). A previous report by Ito et al. [56] indicated that binding to
Glu 515 compromised the acid/base catalyst function, while
interaction with Trp 517 blocked the acceptor glycosyl moiety. These observations can explain the inhibitory properties shown by
acarbose when bound to Gtf-SI [56]. As displayed in figure 5B,
aMG and acarbose interact with Trp 517, which provides the
main frame for the glycosyl acceptor binding site. Since the crystal
structure of GtfB is not yet available, Phyre server [33] was used to
predict ligand sites. The obtained results highlighted the presence
of hydrophobic amino acids Leu 356, Gln 35, Ala 409, Lys 408,
Asn 410; Asp 878, Ser 880; Ser 884, Leu 882, Tyr 936, Phe 881;
Asn 1026 and some other amino acids with electrically charged
amino acids like Asp 838I (Figure 5C). Conversely, sugar uptake by oral streptococci occurs primarily
by means of the PTS system [63]. In this system, phosphoenol-
pyruvate (PEP), provided by glycolysis, is cleaved by Enzyme I and
the phosphate group is transferred to a general phosphocarrier
protein, HPr, which in turn acts as a phosphate donor to
membrane-bound Enzyme II [63]. Thus, the system catalyzes the
transfer of phosphate to an incoming sugar and translocation of it
across the cell membrane to yield a sugar phosphate in the
cytoplasm, at which point sugar is metabolized via glycolytic
pathways to produce organic acids. As shown in Figure 7, the PTS
activity of biofilms treated with aMG was also significantly
inhibited (,50% inhibition vs. vehicle-treated biofilms, P,0.05). Although the exact nature of aMG inhibition of the F-ATPase and
PTS system found in this study remains to be determined using
purified enzymes, our data suggest that aMG can affect S. mutans
biofilms acidogenicity by disrupting the activity of these critical
membrane-associated enzymes (albeit at concentrations of 3–5
times higher than those found against planktonic cells [27]. The inhibitory effects of aMG on F-ATPase and PTS could
have additional impact on biofilm composition and virulence. aMG affects acidogenicity of S. mutans biofilms, and
disrupts F-ATPase and PTS activities The biofilm EPS-matrix and microcolonies provide S. mutans
with niches, where it survives and carries out glycolysis, even at
low pH values, resulting in demineralization of the adjacent dental
enamel [8,39]. In addition to the deleterious effects on biomass
accumulation and structural organization, aMG also affected S. mutans biofilm acidogenicity following topical applications of the
agent (Figure 6). aMG reduced both the acid production and the
acid tolerance of S. mutans biofilm cells as indicated in the pH-
drop profile (Figure 6). The test agent sensitized the biofilm cells to
acidification to the point that the final pH value was significantly
higher (,1 unit) than those treated with vehicle-control (P,0.05),
suggesting that there may be disturbances in the activity of the
proton-translocating membrane F-ATPase [27,39]. October 2014 | Volume 9 | Issue 10 | e111312 aMG compromises the 3D architecture and mechanical
stability of S. mutans biofilms These structural changes may affect the stability of the biofilms
treated with aMG and facilitate mechanical clearance of biofilms. The mechanical stability of biofilms appears to be dependent on
the exopolysaccharide content, as EPS binds the cells together
while strengthening their cohesiveness [15,47–50]. Furthermore,
glucans enhance S. mutans adhesive strength, while the develop- The ability of treated-biofilms to withstand mechanical removal
under shear stress was determined by measuring the amount of
biofilm biomass (dry-weight) that remained on the sHA after
shearing (Figure 4A). We observed that aMG-treated biofilms Figure 8. The expression of S. mutans genes gtfB, gtfC, manL, and atpD in biofilms. Fold changes 6 one standard deviation. Values marked
with asterisks are significantly different from that for the vehicle control (n = 8; P,0.05, pair-wise comparison using Student’s t test). doi:10.1371/journal.pone.0111312.g008 Figure 8. The expression of S. mutans genes gtfB, gtfC, manL, and atpD in biofilms. Fold changes 6 one standard deviation. Values marked
with asterisks are significantly different from that for the vehicle control (n = 8; P,0.05, pair-wise comparison using Student’s t test). doi:10.1371/journal.pone.0111312.g008 October 2014 | Volume 9 | Issue 10 | e111312 PLOS ONE | www.plosone.org 9 a-Mangostin Affects Biofilm Formation by Streptococcus mutans a-Mangostin Affects Biofilm Formation by Streptococcus mutans a-Mangostin Affects Biofilm Formation by Streptococcus mutans and accumulation of intracellular iodophilic polysaccharides (IPS)
[46], which could explain at least in part the marked reduction of
IPS in the treated biofilms (Table 1). The role of IPS in S. mutans
virulence and dental caries in general has been clearly document-
ed [64–66]. IPS provides S. mutans with an endogenous source of
carbohydrates that can be metabolized when exogenous ferment-
able substrates have been depleted within the oral cavity [67]. As a
result, IPS can help to promote the formation of dental caries by
prolonging the exposure of tooth surfaces to organic acids and a
concomitant lower fasting pH in the matrix of the plaque [65]. Thus, the inhibition of IPS accumulation by aMG could also
contribute with the overall disruptive effects of the agent on S. mutans biofilms acidogenicity. through at least three distinctive and yet interconnected ways: 1)
disruption of insoluble EPS-matrix assembly at least in part by
inhibiting GtfB and GtfC enzymatic activities, 2) compromising
the mechanical stability, which may be linked to defective EPS
production and impaired microcolony formation (thereby facili-
tating biofilm detachment from sHA surface), and 3) reducing
acidogenicity by affecting IPS accumulation and the activities of
the F-ATPase and PTS system. The results from this study
indicate that GtfB and GtfC, as well as the F-ATPase and PTS
enzymatic systems, are therapeutic targets of aMG. In conclusion, our study demonstrated that the phytochemical
aMG may represent a potentially useful anti-virulence additive for
the control and/or removal of cariogenic biofilms. Having shown
here that aMG exhibits significant bioactivity against S. mutans
biofilms, further understanding of the molecular mechanisms of
action of this agent as well as its effects on mixed-species cariogenic
biofilm models are certainly warranted. Furthermore, cytotoxicity
studies revealed that aMG is non-toxic and is generally regarded
as safe [68–70]. Clearly, the efficacy of our treatment needs to be
evaluated in vivo using a rodent model of dental caries. Acknowledgments The authors are thankful to Marlise Klein and Stacy Gregoire for technical
assistance during the gene expression and Gtfs assays. The authors are thankful to Marlise Klein and Stacy Gregoire for technical
assistance during the gene expression and Gtfs assays. Table S1
Effects of a-mangostin on biofilm accumula-
tion by S. mutans UA159.
(DOCX) Upon biofilm establishment, the resident microorganisms,
encased in an EPS-rich matrix, are difficult to remove or treat,
while a highly acidogenic and aciduric biofilm environment is
created [20]. In this paper, we reported that topical application of
a-mangostin (aMG) can disrupt some of the major virulence
properties of S. mutans within biofilms, impairing further biofilm
accumulation and acidogenicity, while facilitating mechanical
clearance. Although previous studies have shown the biological
actions of aMG against planktonic cells of S. mutans and other
organisms, this is the first study demonstrating the antibiofilm
effects of this promising phytochemical agent. Analysis of our data
shows that aMG could affect biofilm development by S. mutans References 1. Hall-Stoodley L, Stoodley P (2009) Evolving concepts in biofilm infections. Cell
Microbiol 11: 1034–1043. 12. Burne RA, Marquis RE (2000) Alkali production by oral bacteria and protection
against dental caries. FEMS Microbiol Lett 193(1): 1–6. 13. Smith EG, Spatafora GA (2012) Gene regulation in S. mutans: complex control
in a complex environment. J Dent Res 91(2): 133–141. 2. Dye BA, Tan S, Smith V, Lewis BG, Barker LK, et al. (2007) Trends in oral
health status: United States, 1988–1994 and 1999–2004. Vital Health Stat 11:
1–92. p
J
( )
14. Lemos JA, Quivey RG Jr, Koo H, Abranches J (2013) Streptococcus mutans: a
new Gram-positive paradigm? Microbiology 159(Pt 3): 436–445. 3. Marsh PD (2003) Are dental diseases examples of ecologicalcatastrophes? Microbiology 149: 279–294. 15. Vinogradov AM, Winston M, Rupp CJ, Stoodley P (2004) Rheology of biofilms
formed from the dental plaque pathogen Streptococcus mutans. Biofilms 1: 49–
56. 4. Flemmig TF, Beikler T (2011) Control of oral biofilms. Periodontol 2000 55(1):
9–15. 5. Jeon JG, Rosalen PL, Falsetta ML, Koo H (2011) Natural products in caries
research: current (limited) knowledge, challenges and future perspective. Caries
Res 45: 243–263. 16. Cross SE, Kreth J, Zhu L, Sullivan R, Shi W, et al. (2007) Nanomechanical
properties of glucans and associated cell-surface adhesion of Streptococcus
mutans probed by atomic force microscopy under in situ conditions. Microbiology 153: 3124–3132. 6. Marsh PD (2013) Contemporary perspective on plaque control. Br Dent J
212(12): 601–606. gy
17. Kreth J, Zhu L, Merritt J, Shi W, Qi F (2008) Role of sucrose in the fitness of
Streptococcus mutans. Oral Microbiol Immunol 23(Pt 12): 213–219. 7. Paes Leme AF, Koo H, Bellato CM, Bedi G, Cury JA (2006) The role of sucrose
in cariogenic dental biofilm formation-new insight. J Dent Res 85: 878–887. 18. Xiao J, Klein MI, Falsetta ML, Lu B, Delahunty CM, et al. (2012) The
exopolysaccharide matrix modulates the interaction between 3D architecture
and virulence of a mixed-species oral biofilm. PLoS Pathog 8: e1002623. 8. Bowen WH, Koo H (2011) Biology of Streptococcus mutans-derived glucosyl-
transferases: role in extracellular matrix formation of cariogeneic biofilms. Caries
Res 45: 69–86. 19. Hope CK, Wilson M (2004) Analysis of the effects of chlorhexidine on oral
biofilm vitality and structure based on viability profiling and an indicator of
membrane integrity. Antimicrob Agents Chemother 48: 1461–1468. 9. Author Contributions Conceived and designed the experiments: HK PTMN. Performed the
experiments: PTMN GH MGB. Analyzed the data: PTMN GH MGB
MF. Contributed to the writing of the manuscript: HK PTMN MF MGB. Conceived and designed the experiments: HK PTMN. Performed the
experiments: PTMN GH MGB. Analyzed the data: PTMN GH MGB
MF. Contributed to the writing of the manuscript: HK PTMN MF MGB. Conceived and designed the experiments: HK PTMN. Performed the
experiments: PTMN GH MGB. Analyzed the data: PTMN GH MGB
MF. Contributed to the writing of the manuscript: HK PTMN MF MGB. aMG has limited effects on gtfBC, atpD and manL gene
expression by S. mutans biofilms Treatment of biofilms with a-mangostin could inhibit insoluble
EPS synthesis and glycolytic pH drop in either of the following two
ways:
i)
reducing
enzymatic
function
and/or
ii)
affecting
transcription of the genes encoding these enzymes to reduce the
amount
of
enzyme
produced. Therefore,
we
profiled
the
transcription of gtfB, gtfC, atpD (encoding F-ATPase), and manL
(encoding a key component of the mannose PTS). The expression
profiles of these genes are shown in Figure 8. Overall, RT-qPCR
analysis showed only a slight repression of gtfB and manL after
treatment with aMG (P,0.05), while no significant effects were
observed on gtfC and atpD expression, suggesting that the
reduction in EPS biomass in treated biofilms may be largely due
to the impact on enzymatic function (Figure 5 and 7). Supporting Information Figure S1
Biofilm mechanical strength testing device. This supplementary material shows the design of the custom-built
device to evaluate biofilm mechanical strength, and the principles
of shear stress calculation. (DOCX) Table S1
Effects of a-mangostin on biofilm accumula-
tion by S. mutans UA159. (DOCX) 1. Hall-Stoodley L, Stoodley P (2009) Evolving concepts in biofilm infections. Cell
Microbiol 11: 1034–1043. aMG inhibits GtfB and GtfC activity Cytoplasmic acidification and reduction of sugar transport not
only disrupts glycolytic acid production, but also the formation All amino acids mentioned above are found in catalytic or the
glucan binding regions of both GtfB and GtfC [57–60], suggesting October 2014 | Volume 9 | Issue 10 | e111312 PLOS ONE | www.plosone.org 10 a-Mangostin Affects Biofilm Formation by Streptococcus mutans Koo H, Schobel B, Scott-Anne K, Watson G, Bowen WH, et al. (2005) Apigenin
and tt-farnesol with fluoride effects on Streptococcus mutans biofilms and dental
caries. J Dent Res 84(11): 1016–20. 54. Xiao J, Koo H (2010) Structural organization and dynamics of exopolysacchar-
ide matrix and microcolonies formation by Streptococcus mutans in biofilms. J Appl Microbiol 108: 2103–2113. J
(
)
30. Koo H, Nino de Guzman P, Schobel BD, Vacca Smith AV, Bowen WH (2006)
Influence of cranberry juice on glucan-mediated processes involved in
Streptococcus mutans biofilm development. Caries Res 40(1): 20–7. 55. Gundampati RK, Sahu S, Sonkar KS, Debnath M, Srivastava AK, et al. (2013)
Modeling and molecular docking studies on RNase Aspergillus niger and
Leishmania donovani actin: antileishmanial activity. Am J Biochem Biotechnol
9(3): 318–328. p
p
( )
31. Heydorn A, Nielsen AT, Hentzer M, Sternberg C, Givskov M, et al. (2000)
Quantification of biofilm structures by the novel computer program COM-
STAT. Microbiology 146: 2395–2407. gy
32. Koo H, Xiao J, Klein MI, Jeon JG (2010) Exopolysaccharides produced by
Streptococcus mutans glucosyltransferases modulate the establishment of
microcolonies within multispecies biofilms. J Bacteriol 192: 3024–3032. 56. Ito K, Ito S, Shimamura T, Weyand S, Kawarasaki Y, et al. (2011) Crystal
structure of glucansucrase from the dental caries pathogen Streptococcus mutans. J Mol Biol 408(2): 177–186. 33. Kelley LA, Sternberg MJ (2009) Protein structure prediction on the Web: a case
study using the Phyre server. Nat Protoc 4: 363–371. 57. Monera D, Sereda TJ, Zhou NE, Kay CM, Hodges RS (1995) Relationship of
side chain hydrophobicity and alpha-helical propensity on the stability of the
single-stranded amphipathic alpha-helix. J Pept Sci 1: 319–329. 34. Koo H, Vacca Smith AM, Bowen WH, Rosalen PL, Cury JA, et al. (2000)
Effects of Apis mellifera propolis on the activities of streptococcal glucosyltrans-
ferases in solution and adsorbed ontosaliva-coated hydroxyapatite. Caries Res
34(5): 418–426. 58. Monchois V, Willemot RM, Monsan P (1999) Glucansucrases: mechanism of
action and structure-function relationships. FEMS Microbiol Rev 23: 131–151. 59. Colby SM, Russell RRB (1997) Sugar metabolism by mutans streptococci. Soc
Appl Bacteriol Symp 26: 80S–88S. ( )
35. Venkatraman V, Ritchie DW (2012) Flexible protein docking refinement using
pose-dependent normal mode analysis. Proteins 80(9): 2262–74. 60. Mooser G, Hefta SA, Paxton RJ, Shively JE, Lee TD (1991) Isolation and
sequence of an active-site peptide containing a catalytic aspartic acid from two
Streptococcus sobrinus alpha-glucosyltransferases. a-Mangostin Affects Biofilm Formation by Streptococcus mutans J Biol Chem 266: 8916–22. p
p
y
36. Ritchie DW, Kemp GJ (2000) Protein docking using spherical polar fourier
correlations. Proteins 39: 178–94. 37. Ritchie DW, Venkatraman V (2010) Ultra-fast FFT protein docking on graphics
processors. Bioinformatics 26: 2398–405. p
p
g
y
61. Marquis RE, Clock SA, Mota-Meira M (2003) Fluoride and organic weak acids
as modulators of microbial physiology. FEMS Microbiol Rev 26: 493–510. p
38. Macindoe G, Mavridis L, Venkatraman V, Devignes MD, Ritchie DW (2010)
HexServer: an FFT-based protein docking server powered by graphics
processors. Nucleic Acids Res. 38(Web Server issue): W445–9. 62. Lemos JA, Abranches J, Burne RA (2005) Responses of cariogenic streptococci
to environmental stresses. Curr Issues Mol Biol 7: 95–10. 63. Burne RA, Ahn SJ, Wen ZT, Zeng L, Lemos JA, et al. (2009) Opportunities for
disrupting cariogenic biofilms. Adv Dent Res 21(1): 17–20. p
(
)
39. Belli WA, Marquis RE (1991) Adaptation of Streptococcus mutans and
Enterococcus hirae to acid stress in continuous culture. Appl Environ Microbiol
57: 1134–1138. 64. Loesche WJ, Henry CA (1967) Intracellular microbial polysaccharide produc-
tion and dental caries in a Guatemalan Indian village. Archs Oral Biol 12: 189–
194. 40. Phan TN, Buckner T, Sheng J, Baldeck JD, Marquis RE (2004) Physiologic
actions of zinc related to inhibition of acid and alkali production by oral
streptococci in suspensions and biofilms. Oral Microbiol Immunol 19(1): 31–8. 65. Tanzer JM, Freedman ML, Woodiel FN, Eifert RL, Rinehimer LA (1976)
Association of Streptococcus mutans virulence with synthesis of intracellular
polysaccharide. In: Proceedings in microbiology. Aspects of dental caries. Stiles
HM, Loesche WJ, O’Brien TL, editors. Special supplement to Microbiology
Abstracts, vol. 3. Information Retrieval, Inc. London, 596–616. p
p
41. Cury JA, Koo H (2007) Extraction and purification of total RNA from
Streptococcus mutans biofilms. Anal Biochem 365: 208–14. 42. Yin JL, Shackel NA, Zekry A, McGuinness PH, Richards C, et al. (2001) Real-
time reverse transcriptase-polymerase chain reaction (RT-PCR) for measure-
ment of cytokine and growth factor mRNA expression with fluorogenic probes
or SYBR green. Immunol Cell Biol 79: 213–222. Abstracts, vol. 3. Information Retrieval, Inc. London, 596–616. 66. Spatafora G, Rohrer K, Barnard D, Michalek SA (1995) Streptococcus mutans
mutant that synthesizes elevated levels of intracellular polysaccharide is
hypercariogenic in vivo. Infect Immun 63(7): 2556–263. g
43. Klein MI, DeBaz L, Agidi S, Lee H, Xie G, et al. a-Mangostin Affects Biofilm Formation by Streptococcus mutans 47. Ko¨rstgens V, Flemming HC, Wingender J, Borchard W (2001) Uniaxial
compression measurement device for investigation of the mechanical stability of
biofilms. J Microbiol Methods. 46(1): 9–17. 22. Guo L, Hu W, He X, Lux R, McLean J, et al. (2013) Investigating acid
production by Streptococcus mutans with a surface-displayed pH sensitive green
fluorescent protein. PLoS One 8: e57182. p
23. Li Y, Burne RA (2001) Regulation of the gtfBC and ftf genes of
Streptococcusmutans in biofilms in response to pH and carbohydrate. Microbiology 147(Pt 10): 2841–2848. 48. Cense AW, Peeters EA, Gottenbos B, Baaijens FP, Nuijs AM, et al. (2006)
Mechanical properties and failure of Streptococcus mutans biofilms, studied using
a microindentation device. J Microbiol Methods 67(3): 463–472. gy
(
)
24. Ee GC, Daud S, Taufiq-Yap YH, Ismail NH, Rahmani M (2006) Xanthones
from Garcinia mangostana (Guttiferae). Nat Prod Res 20: 1067–1073. 49. Jones WL, Sutton MP, Mckittrick L, Stewart PS (2011) Chemical and
antimicrobial treatments change the viscoelastic properties of bacterial biofilms
Biofouling 27: 207–15. g
25. Ee GC, Daud S, Izzaddin SA, Rahmani M (2008) Garcinia mangostana: a
source of potential anti-cancer lead compounds against CEM-SS cell line. J Asian Nat Prod Res 10: 475–479. 50. Waters MS, Kundu S, Lin NJ, Lin-Gibson S (2014) Microstructure and
mechanical properties of in situ Streptococcus mutans biofilms. ACS Appl Mater
Interfaces 6(1): 327. 26. Jung HA, Su BN, Keller WJ, Mehta RG, Kinghorn AD (2006) Antioxidant
xanthones from the pericarp of Garcinia mangostana (Mangosteen). J Agric
Food Chem 54: 2077–2082. 51. Simoes M, Pereira MO, Vieira MJ (2004) Effect of cationic surfactants on
biofilm removal and mechanical stability. International Conference on Biofilm
2014: Structure and activity of biofilm Las Vegas, NV, USA. 171–175. 27. Nguyen PTM, Marquis RE (2011) Antimicrobial actions of alpha-mangostin
against oral Streptococci. Can J Microbiol 57: 217–25. 52. Schilling KM, Bowen WH (1992) Glucans synthesized in situin experimental
salivary pellicle function as specific binding sites for Streptococcus mutans. Infect
Immun 60: 284–295. 28. Koo H, Hayacibara MF, Schobel BD, Cury JA, Rosalen PL, et al. (2003)
Inhibition of Streptococcus mutans biofilm accumulation and polysaccharide
production by apigenin and tt-farnesol. J Antimicrob Chemother 52: 782–789. 53. Venkitaraman AR, Vacca-Smith AM, Kopec LK, Bowen WH (1995)
Characterization of glucosyltransferaseB, GtfC, and GtfD in solution and on
the surface of hydroxyapatite. J Dent Res 74(10): 1695–1670. p
y p g
29. References Nyvad B, Crielaard W, Mira A, Takahashi N, Beighton D (2013) Dental caries
from a molecular microbiological perspective. Caries Res 47(2): 89–102. 20. Koo H, Falsetta ML, Klein MI (2013) The exopolysaccharide matrix: a
virulence determinant of cariogenic biofilm. J Dent Res 92(12): 1065–73. 10. Loesche WJ (1986) Role of Streptococcus mutans in human dental decay. Microbiol Rev 50: 353–380. 21. Vroom JM, De Grauw KJ, Gerritsen HC, Bradshaw DJ, Marsh PD, et al. (1999)
Depth penetration and detection of pH gradients in biofilms by two-photon
excitation microscopy. Appl Environ Microbiol 65: 3502–3511. 11. Quivey RG Jr, Kuhnert WL, Hahn K (2000) Adaptation of oral streptococci to
low pH. Adv Microb Physiol 42: 239–74. 11 PLOS ONE | www.plosone.org October 2014 | Volume 9 | Issue 10 | e111312 October 2014 | Volume 9 | Issue 10 | e111312 a-Mangostin Affects Biofilm Formation by Streptococcus mutans (2010) Dynamics of
Streptococcus mutans transcriptome in response to starch and sucrose during
biofilm development. PLoS One 5: e13478. 67. Hamilton IR (1976) Intracellular polysaccharide synthesis by cariogenic
microorganisms. In: Proceedings in microbiology. Aspects of dental caries. Stiles HM, Loesche WJ, O’Brien TL, editors. Special supplement to
Microbiology Abstracts. Vol. 3. London: Information Retrieval, Inc., 683–701. p
44. Bustin SA, Benes V, Garson JA, Hellemans J, Huggett J, et al. (2009) The MIQE
guidelines: minimum information for publication of quantitative real-time PCR
experiments. Clin Chem 55: 611–622. 68. Kaomongkolgit R, Jamdee K, Chaisomboon N (2009) Antifungal activity of a-
mangostin against Candida albicans. J Oral Sci 51(3): 401–406. 45. Falsetta ML, Klein MI, Lemos JA, Silva BB, Agidi S, et al. (2012) Novel
antibiofilm chemotherapy targets exopolysaccharide synthesis and stress
tolerance in Streptococcus mutans to modulate virulence expression in vivo. Antimicrob Agents Chemother 56: 6201–6211. 69. Obolskiy D, Pischel I, Siriwatanametanon N, Heinrich M (2009) Garcinia
mangostana L.: a phytochemical and pharmacological review. Phytother Res
23(8): 1047–1065. 70. Kosem N, Ichikawa K, Utsumi H, Moongkarndi P (2013) In vivo toxicity and
antitumor activity of mangosteen extract. J Nat Med 67(2): 255–263. 46. Hamilton IR (1990) Biochemical effects of fluoride on oral bacteria. J Dent Res
69 (spec issue): 660–667. October 2014 | Volume 9 | Issue 10 | e111312 12 PLOS ONE | www.plosone.org 12
|
https://openalex.org/W4394804455
|
https://link.springer.com/content/pdf/10.1007/s43441-024-00654-1.pdf
|
English
| null |
The FDA Reclassification of Cervical Pedicle and Lateral Mass Screws: A Case Study in Regulatory History
|
Therapeutic innovation & regulatory science
| 2,024
|
cc-by
| 7,639
|
Abstracti The classification of medical devices by the Food and Drug Administration (FDA) involves rigorous scrutiny from special
ized panels that designate devices as Class I, II, or III depending on their levels of relative risk to patient health. Posterior
rigid pedicle screw systems were first classified by the FDA in 1984 and have since revolutionized the treatment of many
spine pathologies. Despite this early classification by the FDA, posterior cervical pedicle and lateral mass screws were not
reclassified from unclassified to Class III and then to Class II until 2019, nearly 35 years after their initial classification. This reclassification process involved a decades-long interplay between the FDA, formal panels, manufacturers, academic
leaders, practicing physicians, and patients. It was delayed by lawsuits and a paucity of data demonstrating the ability to
improve outcomes for cervical spinal pathologies. The off-label use of thoracolumbar pedicle screw rigid fixation systems
by early adopters assisted manufacturers and professional organizations in providing the necessary data for the reclassi
fication process. This case study highlights the collaboration between physicians and professional organizations in facili
tating FDA reclassification and underscores changes to the current classification process that could avoid the prolonged
dichotomy between common medical practice and FDA guidelines. Keywords Cervical screws · Device classification · FDA regulation · Food, drug, and cosmetic act · Lateral mass
screws · Pedicle screw systems The FDA Reclassification of Cervical Pedicle and Lateral Mass Screws: A
Case Study in Regulatory History Jonathan H. Sussman1,2 · Ahmed Albayar1 · Anissa Saylany1 · Bhargavi R. Budihal1 · Dominic Romeo3 · Jason Xu1 ·
Joshua Rosenow4 · Robert F. Heary5 · William C. Welch1 Received: 17 February 2024 / Accepted: 10 April 2024 / Published online: 15 April 2024
© The Author(s) 2024 Jonathan H. Sussman
jonathan.sussman@pennmedicine.upenn.edu 1
Department of Neurosurgery, Perelman School of Medicine,
3400 Civic Center Blvd, Floor 15, 19104 Philadelphia, PA,
USA Keywords Cervical screws · Device classification · FDA regulation · Food, drug, and cosmetic act · Lateral mass
screws · Pedicle screw systems Therapeutic Innovation & Regulatory Science (2024) 58:614–621
https://doi.org/10.1007/s43441-024-00654-1 REVIEW REVIEW Introduction: Current FDA Device
Classification Process The Food and Drug Administration (FDA) is responsible
for classifying the safety of more than 6,500 different medi
cal devices [1]. This is achieved through an often lengthy
process that involves specialty panels within the FDA that
analyze data on these devices. The Federal Food, Drug, and
Cosmetic Act (FD&C Act) mandates that the FDA clas
sify medical devices into one of three classes (Class I-III)
considering the intended use of each device and the data
surrounding the indications for its use (Fig. 1) [2]. The clas
sification involves an evaluation of the “acceptable risk” for
patient health. Each class designates a distinct set of regula
tory controls deemed necessary to ensure safe and effective
use, including special labeling, design specification, perfor
mance standards, and guidance documents [1, 2]. i 1
Department of Neurosurgery, Perelman School of Medicine,
3400 Civic Center Blvd, Floor 15, 19104 Philadelphia, PA,
USA
2
Medical Scientist Training Program, University of
Pennsylvania, Philadelphia, PA, USA
3
Division of Plastic, Reconstructive and Oral Surgery,
Children’s Hospital of Philadelphia, Pennsylvania, USA
4
Department of Neurological Surgery, Northwestern
University Feinberg School of Medicine, Chicago, Illinois,
USA
5
Division of Neurological Surgery, Mountainside Medical
Center, Hackensack Meridian School of Medicine, Montclair,
New Jersey, USA 1
Department of Neurosurgery, Perelman School of Medicine,
3400 Civic Center Blvd, Floor 15, 19104 Philadelphia, PA,
USA 2
Medical Scientist Training Program, University of
Pennsylvania, Philadelphia, PA, USA 2
Medical Scientist Training Program, University of
Pennsylvania, Philadelphia, PA, USA 3
Division of Plastic, Reconstructive and Oral Surgery,
Children’s Hospital of Philadelphia, Pennsylvania, USA 4
Department of Neurological Surgery, Northwestern
University Feinberg School of Medicine, Chicago, Illinois,
USA This process of device classification is dynamic and
continuously evolves as physicians, researchers, and
device manufacturers collect more data about the safety 5
Division of Neurological Surgery, Mountainside Medical
Center, Hackensack Meridian School of Medicine, Montclair,
New Jersey, USA 1 1 3 3 Therapeutic Innovation & Regulatory Science (2024) 58:614–621 615 Therapeutic Innovation & Regulatory Science (2024) 58:614–621 Fig. 1 Flowchart of typical device
classification pathways for a new
medical device Fig. 1 Flowchart of typical device
classification pathways for a new
medical device Fig. 1 Flowchart of typical device
classification pathways for a new
medical device Class I controls apply to all medical devices unless they
receive an exemption upon classification. Examples include
adhesive bandages and stethoscopes. and efficacy of devices. 1976 Medical Devices Amendment location in which the systems are used, from the neck to
the lower back: occipitocervical junction, lower cervical
spine, thoracic and lumbar spine, and lumbosacral spine [8]. Additionally, these systems are further classified by the ana
tomic portion of the spinal vertebrae in which the screws are
inserted, often the lateral mass or the pedicle.i On May 28, 1976, the FDA instituted a set of Medical
Device Amendments to the Federal Food, Drug, and Cos
metic Act (FD&C Act), Sect. 513, to establish the medi
cal device classification system. Section 210(h) of this Act
defined a “medical device” as “any product that does not
achieve its purposes by chemical action or metaboliza
tion.” [4] Medical devices seeking FDA classification are
divided into either “pre-amendment” or “post-amendment”
categories, depending on whether the device was in com
mercial distribution before or after May 28, 1976. This
determination is made through the premarket notification
procedure outlined in Sect. 510(k) of the FD&C Act, and
if these devices came to market after May 28, 1976, then
these devices are automatically classified as Class III, thus
requiring PMA, with the possibility of later reclassification
as either Class III (requiring 510(k)) or Class II after a full
FDA review is completed [4]. i ,
p
Thoracolumbar pedicle screw systems were first pro
posed by Raymond Roy-Camille of France in the early
1960s to treat spinal fractures, and they were subsequently
marketed in the United States [9]. In the 1970s, Roy-Camille
later introduced posterior cervical lateral mass screw fixa
tion systems that were quickly adopted by spine surgeons
globally for spinal stabilization [10]. The development of
cervical pedicle screw fixation systems followed in the
late 1980s and early 1990s [11]. The combination of these
advancements ultimately revolutionized the modern treat
ment of cervical spinal disorders [11]. Collectively, these
systems mechanically align segments of the spine using a
metal structure in order to provide three-column support
of the spinal vertebrae, thus facilitating bony fusion [12]. These devices allow for rigid fixation even in the face of
aggressive bony decompression and offer more effective
resistance to lateral bending and axial rotation compared to
previous devices [13–15]. This has dramatically improved
the postoperative course of patients undergoing posterior
cervical fusions and has contributed to the increased utili
zation of posterior cervical fusions to treat cervical spine
pathologies [16, 17]. 1976 Medical Devices Amendment Despite the advantages of the posterior
cervical pedicle and lateral mass screws, and their routine
use in clinical practice, it was not until 2019 that the FDA
reclassified them from an unclassified category to Class II
devices [18]. Pre-amendment devices are classified according to the
following process. First, the FDA receives recommenda
tions from an FDA-instituted device classification panel. Then, the FDA publishes the panel’s recommendations with
their proposed regulations for public comments. Lastly, the
FDA publishes a final regulation designation that classifies
the device through an administrative order [5]. i Post-amendment devices are automatically classified as
Class III without any FDA rulemaking proceedings. These
devices remain Class III unless the device is reclassified as
Class I or II unless the FDA finds the device equivalent to a
device not requiring PMA [5]. The later reclassification of a
medical device by administrative order can take place based
on the re-evaluation of data available at the time of initial
classification or additional publicly available data that offers
new insight into device safety and efficacy [6]. Introduction: Current FDA Device
Classification Process Importantly, there is often a sig
nificant dichotomy between common medical practice and
FDA guidelines, as physicians frequently use devices for
indications other than those for which the device is specifi
cally approved to be marketed, highlighted here through
the history of cervical screws. While physicians are per
mitted to use devices off-label, there is value in aligning
FDA classifications with clinical practice. Beyond issues of
medical liability, appropriate device classifications improve
reimbursement and insurance coverage for patients, mak
ing devices more accessible. In addition, accurate classifi
cations facilitate the development and marketing of future
devices, which can gain approval based on similarities to
existing products. Physicians play an active role in this pro
cess through routine clinical practice and the curation of
clinical data. Therefore, it is beneficial for practicing physi
cians to be familiar with the complexities of this process and
recognize the importance of their collective roles in device
regulation. Class II devices are considered moderate-risk devices
that require both general and special controls. The special
controls are device-specific and include oversight of per
formance standards, post-market surveillance, patient reg
istries, special labeling, premarket data requirements, and
guidelines. These devices span a broad range from simple
devices such as surgical masks and electric wheelchairs to
more complex devices such as blood transfusion devices
and electric wheelchairs. Class III devices are considered high-risk devices that
“support or sustain human life” and are therefore subject
to the most stringent regulatory controls, requiring both
general controls and premarket approval (PMA) [2]. Gain
ing PMA requires an application that functions as a private
license to market a particular device. If a Class III device
fails to meet PMA requirements, Sect. 501(f) of the FD&C
Act prohibits it from being marketed for clinical use. This
category includes most implantable devices such as implant
able neurostimulators and breast implants. Overall, 35% of
all devices are Class I, 53% are Class II, 9% are Class III,
and 3% are unclassified [1–3]. The three device classes are as follows: Class I devices
are those for which general controls of the FD&C Act can
ensure safety and efficacy. These controls include protec
tions against the misbranding of devices, oversight of device
registrations and records, and general reports on devices. 1 3 Therapeutic Innovation & Regulatory Science (2024) 58:614–621 616 1 3 The Role of the Rigid Pedicle Screw Systems
in Spine Surgery The first premarket notification 510(k) submission to the
FDA for spinal device systems used for attachment to the
spine via lumbar pedicles was in 1984 [6]. At the time, the
FDA decided that the pedicle devices were not substan
tially equivalent to other approved devices and expressed
concern about unique risks such as potential neurological
deficits due to imprecise screw placement and screw failure. These devices are placed in close proximity to the spinal
cord, and possible misalignment or breakdown over time
could, in theory, lead to irreversible spinal cord damage and
paralysis. Thus, pedicle screw systems were made Class III
devices under Sect. 513(f) of the FD&C Act [6]. Despite
the numerous benefits of these systems, given the theoreti
cal possible for life-threatening adverse events, the most
stringent classification was necessary to ensure rigorous Medical issues related to the spine such as chronic back pain
are exceedingly common. Approximately 900,000 adults in
the U.S. undergo spine surgery annually, most commonly
receiving spinal decompression or fusion surgeries, which
involve some form of spinal fixation [7]. Spinal fixation is a
common technique used for many conditions, including spi
nal fractures, reconstruction after tumor removal, scoliosis,
spondylolisthesis, disk disease, and degenerative arthritis
[8]. This improves spinal stability, allowing for better heal
ing, greater mobility, and decreased pain. In current medical
practice, there is a wide range of instrumentation and tech
niques, but can be divided generally based on the anatomic 1 3 Therapeutic Innovation & Regulatory Science (2024) 58:614–621 617 autogenous bone graft fusion in severe L5-S1 spondylolis
thesis, with device removal post-fusion, as Class II [19]. In addition, the thoracolumbosacral pedicle screw systems
were recommended for use in spinal trauma and formally
proposed for the treatment of acute and chronic spinal insta
bility and deformity. On July 17, 1998, the FDA issued a
final ruling to classify pedicle screw spinal systems as Class
II devices when used specifically to provide immobilization
and stabilization of thoracic, lumbar, and sacral spinal seg
ments as an adjunct to fusion in the treatment of degenera
tive spondylolistheses. All other indications were deemed
Class III, and thus still required a PMA for advertisement
of use in those indications [19]. In this same ruling, cervical
pedicle screws were excluded from updated classification
and were still considered post-amendment Class III devices
with the FDA, citing insufficient safety and efficacy evi
dence [19]. manufacturing oversight. Petitions and Panels for Reclassification of
Cervical Pedicle Screw Spinal Systems On May 22, 2001, the FDA issued a technical amendment
to its 1998 ruling. In this amendment, the FDA noted that
lateral mass and pedicle screw systems in the cervical spine
were in use before 1976 and should instead be considered
pre-amendment Class III devices instead of post-amend
ment Class III devices. This ruling subjected cervical spine
pedicle screw systems to specific regulations such as requir
ing 510(k) premarket notifications [20]. p
pp
In July 1994, the FDA advisory panel evaluated the
SIMG cohort study and two meta-analyses of the literature
pertaining to the clinical performance of pedicle screw spi
nal devices [6]. The panel also heard testimonies of patients
with pedicle screw instrumentation, litigation attorneys with
lawsuits against spine implant manufacturers, and spine
surgeons. The panel concluded that pedicle screw use in
spinal instrumentation systems, specifically in the thoraco
lumbosacral spinal systems, was appropriate for the treat
ment of spinal instabilities including trauma, deformity,
tumor reconstruction, and spondylolisthesis. However, they
expressed concern about their use for degenerative disc dis
ease due to a dearth of satisfactory data on the topic. Ulti
mately, the panel recommended that the FDA reclassify
generic pedicle screw spinal systems from Class III to Class
II for the treatment of degenerative spondylolisthesis and
spinal trauma. At this point, the FDA had not yet directly
addressed pedicle screw or lateral mass screw utilization in
the cervical spine in panels or formal proposals, and cervi
cal screws remained Class III devices [6]. Eight years later, on April 9, 2009, the FDA published an
order under Sect. 515(i) of the FD&C Act (21 U.S.C. 360i)
calling for additional information on the remaining Class
III 510(k) pre-amendment devices including the thoraco
lumbosacral pedicle screw spinal systems [21]. However,
the classification of posterior cervical screws was deferred
due to a lack of prior input from the FDA advisory panel. Responses to this 515(i) order concerning thoracolumbosa
cral spinal systems unanimously supported Class II designa
tion with assurances provided by special controls such as
labeling, biocompatibility, sterility, and mechanical testing
[21]. This was an important advancement because Class II
devices are deemed lower risk than Class III devices, and
therefore, can be more readily used in patient care. Addi
tionally, designation from Class III to Class II has the poten
tial to improve insurance coverage of certain procedures,
making them more accessible to patients. The Role of the Rigid Pedicle Screw Systems
in Spine Surgery By 1985, clinical investigations of
pedicle screw spinal systems under investigational device
exemption (IDE) protocols began, allowing pedicle screw
spinal systems to be used in clinical studies to collect data to
support a PMA application, a humanitarian device exemp
tion (HDE), or a premarket notification 510(k) submission
to the FDA [6]. By 1992, the FDA acknowledged that the use of pedicle
screw spine systems outside of approved IDE studies was
widespread in the surgical community to the point that they
were considered “standard of care.” [6] Then, in February
1993, the FDA called for the submission of all available
data on pedicle screw systems. This prompted the formation
of the Spinal Implant Manufacturers Group (SIMG) which
consisted of representatives from the American Academy of
Orthopedic Surgeons (AAOS), the Scoliosis Research Soci
ety (SRS), the North American Spine Society (NASS), the
American Association of Neurological Surgeons (AANS),
the Congress of Neurological Surgeons (CNS), and 25 spi
nal implant manufacturers. The SIMG scientific commit
tee, with FDA support, conducted a nationwide historical
cohort study of pedicle screw fixation in thoracic, lumbar,
and sacral spine surgeries [6, 19]. On August 20, 1993, the
FDA convened an advisory panel to review the IDE data,
mechanical testing data, and presentations by experts. The
FDA advisory panel concluded that pedicle screw spinal
systems were reasonably safe spinal fusion adjuncts; how
ever, they held that more clinical information was needed
for the establishment of the necessary regulatory controls
prior to their approval [6]. Final Classification Proposals and Rulings In November 2014, the FDA proposed the reclassification of
rigid pedicle screw systems based on new information. At
the time of the proposal, rigid thoracolumbosacral pedicle
screw systems were still Class III pre-amendment devices
for some spinal pathologies. The proposed administrative
order, as governed by Sect. 513(e) of the FD&C Act, would
reclassify rigid pedicle screw systems when intended to pro
vide immobilization and stabilization of spinal segments in
the thoracic, lumbar, and sacral spines as adjuncts to fusions
in the treatment of degenerative disc disease and spondylo
listhesis (with the previously noted exception) from Class
III to Class II [27]. On August 28, 2012, a panel from the AANS/CNS sub
mitted another letter with comments regarding lateral mass
and pedicle screw spinal system classification in response to
the FDA Orthopedic and Rehabilitation Devices Panel meet
ing of the medical devices advisory committee (MDAC)
[24]. This letter emphasized the anatomical and biomechan
ical advantages of posterior cervical screws in comparison
to FDA-approved devices and pointed to many studies that
supported their safety and utility. They emphasized that
pedicle screws used in the posterior cervical spine were
widely considered standard of care and called for Class II
designation for posterior cervical lateral mass and pedicle
screw systems [24]. On March 10, 2016, the FDA proposed the classification
of posterior cervical screw systems—including lateral mass
and pedicle screws—as Class II. Posterior cervical screw
systems were identified as those intended to provide immo
bilization and stabilization of spinal segments in patients
as an adjunct to fusion for acute and chronic instabilities
involving the cervical spine. The proposal claimed that
while cervical pedicle screw systems are similar in design
and operation to thoracolumbosacral pedicle screw spinal
systems, they differ with respect to anatomical use and
clinical indications. Therefore, they had to be considered
separately in terms of classification and determination of
necessary controls [28]. In September 2012, the FDA consulted with the Ortho
pedic and Rehabilitation Devices Panel FDA advisory com
mittee regarding posterior cervical pedicle and lateral mass
screw spinal systems. Based on their expertise and histori
cal data, the panel noted effective posterior cervical ped
icle and lateral mass screw spinal systems were in use as
adjuncts to fusion for acute and chronic instabilities of the
cervical spine and craniocervical junction [23]. Petitions and Panels for Reclassification of
Cervical Pedicle Screw Spinal Systems In May 2010, the Orthopedic Surgical Manufacturers
Association (OSMA) responded to the 515(i) order with a
petition declaring that posterior screws, particularly pedicle
screws, should be deemed Class II devices for use in degen
erative disc disease, pediatrics, and the posterior cervical In 1995, the FDA advisory panel formally recom
mended reclassifying pedicle screw spinal systems used for 1 3 Therapeutic Innovation & Regulatory Science (2024) 58:614–621 618 spine [22]. In November 2010, the AANS and CNS also
submitted comments in support of the OSMA petition. In
this letter, the organizations pointed to the challenges of
the growing off-label use of cervical pedicle screw spinal
devices, including medical liability for surgeons, inappro
priate denial of insurance coverage, and published lack of
trust in the validity of use and cost [22]. The inclusion of
data regarding posterior cervical screws from OSMA and
others was outside the scope of the original 2009 FDA “call
for information.” The topic of posterior cervical pedicle
screw systems had yet to be formally addressed in a clas
sification panel meeting and it was required that a panel be
convened per Sect. 513(b) of the FD&C Act [23]. There
fore, the FDA requested that OSMA prepare and submit a
separate petition for classification. meeting’s conclusion, an unofficial vote by the panel was in
favor of posterior cervical pedicle and lateral mass screw
spinal systems to be designated as Class II devices [25]. In May 2013, the same panel convened and recommended
that rigid pedicle screw systems have an additional Class II
designation when used in the thoracic, lumbar, and sacral
spines as adjuncts to fusion for degenerative disc disease
and spondylolisthesis (other than either severe spondylolis
thesis grade 3 or 4 at L5-S1 or degenerative spondylolisthe
sis with objective evidence of neurologic impairment). In
support of their recommendation, the panel included a sum
mary of safety and effectiveness information, a literature
review, and a review of adverse event reports from the Man
ufacturer and User Facility Devices Experience (MAUDE)
database [26]. In November 2011, OSMA submitted a petition for lat
eral mass and pedicle screw spinal systems to be moved
to a Class II designation. In this petition, OSMA sought to
reclassify cervical pedicle screw systems at levels C1 to T3
as Class II due to the ability of the general and special con
trols to provide a reasonable assurance of safety and effec
tiveness [22]. Petitions and Panels for Reclassification of
Cervical Pedicle Screw Spinal Systems The petition included a literature search of
cervical spine pedicle screw systems in practice (including
data from 1999 to 2009) and identified that such systems
offered patients improved or preserved neurological func
tion, improvements in pain/discomfort, and higher fusion
rates when compared to already Class II-designated cervical
spinal sublaminar hooks, sublaminar cables, and interspi
nous process wiring [22]. 1 3 Improving Device Classification Through
Data-Driven Collaboration This case study of the FDA classification of cervical pedicle
and lateral mass screws presents a comprehensive history
of a significant medical device (summarized in Table 1) and
illustrates the complexities of the FDA regulatory process. This process has involved a decades-long interplay between
the FDA, formal panels, manufacturers, academic leaders,
and practicing physicians, and only recently concluding. Moreover, it is critical that this data is cogently presented
to the FDA. The FDA has no direct interest in down classi
fying devices because its primary role is in keeping patients
safe. Therefore, without the active engagement of physi
cians– as facilitated and promoted by professional organi
zations– the reclassification presented here would not have
taken place. Although the process was lengthy, the FDA
indeed served its intended purpose in fairly reviewing the
data to presented to it and remaining cautious in loosening
regulations. Physicians ultimately guided this endeavor and
should recognize the invaluable role they play in shaping
the process of device classification and enabling the adop
tion of new technologies. Notably, cervical screws are an unlikely member of the
Class II family, given that they are surgically implanted,
which typically requires Class III controls, and may not
seem to be in the same risk category as other Class II devices
such as surgical masks and electric wheelchairs. The history
of cervical screws reveals that our understanding of medi
cal risk is continuously developing and evolves with data
that is collected across thousands of patients over decades,
with this acquisition of knowledge informing the classifi
cation of medical devices. While certain life-sustaining
devices such as implantable pacemakers will likely remain
as Class III due to their need for the most stringent safety
controls, this case study suggests the possibility that other
current Class III implantable devices may be reclassified to
Class II, and that perhaps simple Class II devices may even
tually be reclassified to Class I. Doing so would decrease
regulatory costs, promote their use in clinical practice, and
improve insurance coverage, ultimately rendering devices
more accessible to a broader patient population and improv
ing their care. Finally, the FDA has an obligation to facilitate this col
laboration through improved transparency and data shar
ing. Although FDA regulatory meetings are often public,
and transcripts are released, the exact data and analysis
that guides these decisions are rarely compiled and nearly
impossible to locate. Final Classification Proposals and Rulings The panel
did express concerns regarding a lack of long-term data and
the need for additional data on specific screw types. At the The FDA also conducted a literature review that included
data until July 2012 reviewing published clinical studies as
well as a review of adverse events in the MAUDE Database. This review, along with advice from the September 2012
Panel, suggested that Class II controls would be sufficient
to ensure the safety and efficacy of posterior cervical screw
systems. Additionally, an economic analysis urged that the
reclassification of posterior cervical screw systems to Class 1 3 619 Therapeutic Innovation & Regulatory Science (2024) 58:614–621 II would not have a negative economic impact on various
small entities as only five registered establishments at the
time would have been affected by the proposed rule [23]. II would not have a negative economic impact on various
small entities as only five registered establishments at the
time would have been affected by the proposed rule [23]. professional societies, and the FDA to provide and interpret
safety and efficacy data. The decades-long debates about
the safety of cervical pedicle and lateral mass screws were
driven by a lack of definitive and reliable data. Specifically,
although these devices were used routinely in clinical prac
tice for decades, the data on patient safety and efficacy was
not sufficiently generalizable to the broad population of
patients who may be treated by these medical devices. This
requires that data be collected and analyzed to understand
the effects of age, genetic background, comorbidities, and
social factors on the safety and efficacy of medical treat
ments. However, healthcare providers and clinical research
ers must take a proactive initiative to curate this information
and conduct appropriate and rigorous analyses demonstrat
ing that their conclusions can be generalized. Additionally,
studies conducted in different medical centers may not be
readily comparable due to discrepancies in patient popula
tions and medical practices. Integrating disparate studies
is challenging, and future regulatory efforts would benefit
from more robust meta-analyses that curate larger amounts
of clinical data to synthesize stronger conclusions. Following the March 2016 proposal, on December 30,
2016, the FDA put forth a final order to classify thoracic,
lumbar, and sacral rigid pedicle screw systems as adjuncts
to fusions in the treatment of degenerative disc disease and
spondylolisthesis (with the previously noted exception)
as Class II devices [4]. Final Classification Proposals and Rulings Lastly, on April 1, 2019, the FDA
issued a final rule to classify posterior cervical screw sys
tems as Class II, with a continued requirement of premarket
notification 510(k) to ensure reasonable safety and effec
tiveness of the device [18, 28]. Mid 1992
The FDA acknowledged the off-label use of pedicle screws.
February
The FDA called for submission of pedicle screw system-related data. The FDA advisory panel found pedicle screw spinal systems to be reasonably safe spinal
fusion adjuncts; however, they desired additional data prior to establishing regulatory
controls around their use. e FDA advisory panel concluded that the use of pedicle screw spinal systems in
e thoracolumbosacral spine was appropriate for treating spinal instabilities, but they
pressed concern about the use for degenerative disc disease. Ultimately the panel rec
mmended that the FDA reclassify generic pedicle screw spinal systems from Class III to
ass II for treating degenerative spondylolisthesis and spinal trauma. At this point, the
DA had not formally addressed the use of the pedicle screw system in the cervical spine. e FDA formally proposed that pedicle screw spinal systems used for autogenous
ne graft fusions in patients with severe L5-S1 spondylolisthesis with device removal
st-fusion be classified to Class II. The FDA also recommended post-amendment
oracolumbosacral pedicle screw spinal systems intended for use in spinal trauma and
generative spondylolisthesis be reclassified from Class III to Class II. Additionally,
ey proposed expanding the intended use of pedicle screw spinal systems to include
mobilization and stabilization of spinal segments as an adjunct to fusion for the treat
ent of acute and chronic instabilities and deformities. The FDA issued a rule that set forth stipulations to split pedicle screw spinal systems into
different classification categories. They classified pedicle screw spinal systems as Class
II devices when used to provide immobilization and stabilization of thoracic, lumbar, and
sacral spinal segments as an adjunct to fusion in the treatment of degenerative spondy
lolisthesis with objective evidence of neurologic impairment, fracture, dislocation, scolio
sis, kyphosis, tumor, and/or failed prior fusion. All other indications were deemed Class
III, requiring a PMA for use. The FDA issued a technical amendment to their 1998 ruling that included an additional
use for Class II designation: pedicle screw spinal systems in the treatment of severe spon
dylolisthesis (grades 3 and 4) at the L5-S1 level as an adjunct to fusion. The FDA called for information on the remaining Class III 510(k) pre-amendment
devices, of which pedicle screw spinal systems for use in the thoracic, lumbar, and sacral
spine as an adjunct to fusion for treatment of degenerative disc disease and types of spon
dylolisthesis for which the classification process had yet to be finalized. The FDA consulted the Orthopedic and Rehab Devices Panel FDA advisory commit
tee regarding cervical screw systems. Improving Device Classification Through
Data-Driven Collaboration The proposal claimed that given cervical pedicle screw systems differed in
indication and anatomical location to thoracolumbosacral pedicle screw spinal systems,
they had to be classified separately from each other. December
2016
The FDA suggested classifying thoracic, lumbar, and sacral rigid pedicle screw systems
adjuncts to fusions in treating degenerative disc disease and spondylolisthesis as Class II
devices. Posterior cervical screws remained unclassified. April 2019
The FDA issued a final rule to reclassify posterior cervical screw systems as Class II,
with a continued requirement of premarket notification 510(k) to ensure reasonable safety
and effectiveness of the device. Mid 1992
The FDA acknowledged the off-label use of pedicle screws. February
1993
The FDA called for submission of pedicle screw system-related dat
August 1993
The FDA advisory panel found pedicle screw spinal systems to be r
fusion adjuncts; however, they desired additional data prior to estab
controls around their use. July 1994
The FDA advisory panel concluded that the use of pedicle screw sp
the thoracolumbosacral spine was appropriate for treating spinal ins
expressed concern about the use for degenerative disc disease. Ultim
ommended that the FDA reclassify generic pedicle screw spinal sys
Class II for treating degenerative spondylolisthesis and spinal traum
FDA had not formally addressed the use of the pedicle screw system
October 1995
The FDA formally proposed that pedicle screw spinal systems used
bone graft fusions in patients with severe L5-S1 spondylolisthesis w
post-fusion be classified to Class II. The FDA also recommended po
thoracolumbosacral pedicle screw spinal systems intended for use i
degenerative spondylolisthesis be reclassified from Class III to Clas
they proposed expanding the intended use of pedicle screw spinal s
immobilization and stabilization of spinal segments as an adjunct to
ment of acute and chronic instabilities and deformities. July 1998
The FDA issued a rule that set forth stipulations to split pedicle scre
different classification categories. They classified pedicle screw spin
II devices when used to provide immobilization and stabilization of
sacral spinal segments as an adjunct to fusion in the treatment of de
lolisthesis with objective evidence of neurologic impairment, fractu
sis, kyphosis, tumor, and/or failed prior fusion. All other indications
III, requiring a PMA for use. Author Contributions All authors contributed the writing and review
of this manuscript. Improving Device Classification Through
Data-Driven Collaboration Furthermore, it is unclear what pre
cisely dictated the final votes of the panel members in this
case. How the data was presented at the meeting and inter
preted by the panel could lead to poor decisions with little
corrective mechanism. It would be beneficial for the FDA
to provide a comprehensive and quantitative overview of
the relevant data presented and the interpretations by panel
members. This would enable the broader academic commu
nity to critique the methods and conclusions in the same
way that peer-reviewed studies are ultimately scrutinized
after publication. By facilitating a more active and produc
tive collaboration with physicians and manufacturers, the Looking back on this tumultuous process, this review
elucidates specific ways in which healthcare providers,
manufacturers, and regulators can make the classification
process more effective. Primarily, these events demonstrate
that the reclassification process will not occur spontane
ously and requires the active engagement and collaboration
between physicians, clinical researchers, manufacturers, 1 3 620 Therapeutic Innovation & Regulatory Science (2024) 58:614–621 Therapeutic Innovation & Regulatory Science (2024) 58:614–621
between typical medical practice and FDA guidelines and
facilitate classifications that most accurately reflect the cur
rent regulatory needs for common medical devices. ificantly expedited this reclas
sing patient safety. tory of cervical pedicle and lat
tes how physicians and device
Mid 1992
The FDA acknowledged the off-label use of pedicle screws. February
1993
The FDA called for submission of pedicle screw system-related data. August 1993
The FDA advisory panel found pedicle screw spinal systems to be reasonably safe spinal
fusion adjuncts; however, they desired additional data prior to establishing regulatory
controls around their use. July 1994
The FDA advisory panel concluded that the use of pedicle screw spinal systems in
the thoracolumbosacral spine was appropriate for treating spinal instabilities, but they
expressed concern about the use for degenerative disc disease. Ultimately the panel rec
ommended that the FDA reclassify generic pedicle screw spinal systems from Class III to
Class II for treating degenerative spondylolisthesis and spinal trauma. At this point, the
FDA had not formally addressed the use of the pedicle screw system in the cervical spine. October 1995
The FDA formally proposed that pedicle screw spinal systems used for autogenous
bone graft fusions in patients with severe L5-S1 spondylolisthesis with device removal
post-fusion be classified to Class II. Improving Device Classification Through
Data-Driven Collaboration The FDA also recommended post-amendment
thoracolumbosacral pedicle screw spinal systems intended for use in spinal trauma and
degenerative spondylolisthesis be reclassified from Class III to Class II. Additionally,
they proposed expanding the intended use of pedicle screw spinal systems to include
immobilization and stabilization of spinal segments as an adjunct to fusion for the treat
ment of acute and chronic instabilities and deformities. July 1998
The FDA issued a rule that set forth stipulations to split pedicle screw spinal systems into
different classification categories. They classified pedicle screw spinal systems as Class
II devices when used to provide immobilization and stabilization of thoracic, lumbar, and
sacral spinal segments as an adjunct to fusion in the treatment of degenerative spondy
lolisthesis with objective evidence of neurologic impairment, fracture, dislocation, scolio
sis, kyphosis, tumor, and/or failed prior fusion. All other indications were deemed Class
III, requiring a PMA for use. May 2001
The FDA issued a technical amendment to their 1998 ruling that included an additional
use for Class II designation: pedicle screw spinal systems in the treatment of severe spon
dylolisthesis (grades 3 and 4) at the L5-S1 level as an adjunct to fusion. April 2009
The FDA called for information on the remaining Class III 510(k) pre-amendment
devices, of which pedicle screw spinal systems for use in the thoracic, lumbar, and sacral
spine as an adjunct to fusion for treatment of degenerative disc disease and types of spon
dylolisthesis for which the classification process had yet to be finalized. September
2012
The FDA consulted the Orthopedic and Rehab Devices Panel FDA advisory commit
tee regarding cervical screw systems. The panel members cited their knowledge and
clinical experiences with cervical screw systems, and the historical data for the safety
and efficacy of such devices. At the meeting’s conclusion, an unofficial vote favored the
designation of posterior cervical screws as Class II devices. November
2014
The FDA proposed reclassifying rigid pedicle screw systems based on “new informa
tion.” At this time, rigid thoracolumbosacral pedicle screw systems were largely deemed
Class III devices. March 2016
The FDA proposed the classification of posterior cervical lateral mass and pedicle
screw systems as Class II. Posterior cervical screw systems were identified as those that
provided immobilization and stabilization of spinal segments in patients as an adjunct to
fusion for instabilities of the cervical spine, craniocervical junction, and/or cervicotho
racic junction. Table 1 Timeline of FDA clas
sifications of the spinal pedicle
screw rigid systems highlighting
the separation between thoraco
lumbosacral fusions and their use
for posterior cervical fusions Improving Device Classification Through
Data-Driven Collaboration May 2001
The FDA issued a technical amendment to their 1998 ruling that inc
use for Class II designation: pedicle screw spinal systems in the trea
dylolisthesis (grades 3 and 4) at the L5-S1 level as an adjunct to fus
April 2009
The FDA called for information on the remaining Class III 510(k) p
devices, of which pedicle screw spinal systems for use in the thorac
spine as an adjunct to fusion for treatment of degenerative disc dise
dylolisthesis for which the classification process had yet to be finali
September
2012
The FDA consulted the Orthopedic and Rehab Devices Panel FDA
tee regarding cervical screw systems. The panel members cited thei
clinical experiences with cervical screw systems, and the historical
and efficacy of such devices. At the meeting’s conclusion, an unof
designation of posterior cervical screws as Class II devices. November
2014
The FDA proposed reclassifying rigid pedicle screw systems based
tion.” At this time, rigid thoracolumbosacral pedicle screw systems
Class III devices. March 2016
The FDA proposed the classification of posterior cervical lateral ma
screw systems as Class II. Posterior cervical screw systems were id
provided immobilization and stabilization of spinal segments in pat
fusion for instabilities of the cervical spine, craniocervical junction,
racic junction. The proposal claimed that given cervical pedicle scre
indication and anatomical location to thoracolumbosacral pedicle sc
they had to be classified separately from each other. December
2016
The FDA suggested classifying thoracic, lumbar, and sacral rigid pe
adjuncts to fusions in treating degenerative disc disease and spondy
devices. Posterior cervical screws remained unclassified. April 2019
The FDA issued a final rule to reclassify posterior cervical screw sy
with a continued requirement of premarket notification 510(k) to en
and effectiveness of the device. Table 1 Timeline of FDA clas
sifications of the spinal pedicle
screw rigid systems highlighting
the separation between thoraco
lumbosacral fusions and their use
for posterior cervical fusions 1 3 References 19. Schultz WB. Orthopedic Devices: Classification and Reclassifica
tion of Pedicle Screw Spinal Systems. Federal Register. 63(143).ii 1. Rathi VK, Ross JS. Modernizing the FDA’s 510(k) pathway. N Engl J Med. 2019;381(20):1891–3. https://doi.org/10.1056/
NEJMp1908654. 20. Dotzel MM. Orthopedic devices: classification and reclassifica
tion of Pedicle Screw Spinal Systems; Technical Amendment. Fed Reg. 2001;66(99). p
2. Sastry A. Overview of the US FDA Medical device approval pro
cess. Curr Cardiol Rep. 2014;16(6):494. https://doi.org/10.1007/
s11886-014-0494-3. 21. Chambers J. Medical devices; order for certain class III devices;
submission of Safety and Effectiveness Information. Fed Reg. 2009;74(67).i 3. Anderson L, Antkowiak P, Asefa A, et al. FDA Regulation of
Neurological and Physical Medicine devices: Access to Safe
and Effective neurotechnologies for all americans. Neuron. 2016;92(5):943–8. https://doi.org/10.1016/j.neuron.2016.10.036.i 22. Starowicz S. Petition for reclassification: posterior cervical
pedicle and lateral Mass screws. Published Online November. 2011;22:513.i ( )
p
g
j
4. Kux L. Orthopedic Devices; reclassification of Pedicle Screw
systems, henceforth to be known as Thoracolumbosacral Ped
icle Screw Systems, including Semi-rigid systems. Fed Reg. 2016;81(251). 23. Petition to Request Classification for Posterior Cervical Pedicle
and Lateral Mass Screw Spinal Systems. FDA Executive Sum
mary. Published online September 21, 2012.i 24. Berger M. Classification of posterior cervical screws, including
pedicle and lateral mass screws [Docket No. FDA–2012–N–0001]
FDA Orthopaedic and Rehabilitation Devices Panel of the Medi
cal Devices Advisory Committee. Published online August 28,
2012. ;
(
)
5. Lauer M, Barker JP, Solano M, Dubin J. FDA device regulation. Mo Med. 2017;114(4):283–8.ii 6. Armstrong HA. Orthopedic devices: classification, reclassifica
tion, and codification of pedicle screw spinal systems. Fed Reg. 1995;60(192). 25. Anderson SJ. Brief Summary of the Orthopedic and Rehabili
tation Devices Panel Meeting– September 21, 2012. Published
online September 21, 2012.i 7. Cram P, Landon BE, Matelski J, et al. Utilization and out
comes for spine surgery in the United States and Canada. Spine
(Phila Pa 1976). 2019;44(19):1371–80. https://doi.org/10.1097/
BRS.0000000000003083.i 26. Kavlock K. Classification discussion: pedicle screw spinal sys
tems (certain uses - Class III indications for Use). Meeting of
Orthopaedic and Rehabilitation Devices Panel presented at: May
22, 2013; Gaithersburg, MD.i 8. Slone RM, MacMillan M, Montgomery WJ. Spinal fixation. Part
1. Principles, basic hardware, and fixation techniques for the
cervical spine. Radiographics. 1993;13(2):341–56. https://doi. org/10.1148/radiographics.13.2.8460224. 27. Barnes RA. Orthopedic Devices; reclassification of thoracolum
bosacral rigid pedicle Screw systems; classification and effective
date of requirement for Premarket approval for dynamic stabiliza
tion systems. Declarations 13. Tan M, Wang H, Wang Y, et al. Morphometric evalua
tion of screw fixation in Atlas via posterior arch and lateral
Mass. Spine. 2003;28(9):888–95. https://doi.org/10.1097/01. BRS.0000058719.48596.CC.i Competing Interests The authors declare no competing interests. Competing Interests The authors declare no competing interests. Open Access This article is licensed under a Creative Commons
Attribution 4.0 International License, which permits use, sharing,
adaptation, distribution and reproduction in any medium or format,
as long as you give appropriate credit to the original author(s) and the
source, provide a link to the Creative Commons licence, and indicate
if changes were made. The images or other third party material in this
article are included in the article’s Creative Commons licence, unless
indicated otherwise in a credit line to the material. If material is not
included in the article’s Creative Commons licence and your intended
use is not permitted by statutory regulation or exceeds the permitted
use, you will need to obtain permission directly from the copyright
holder. To view a copy of this licence, visit http://creativecommons. org/licenses/by/4.0/. 14. Huang DG, Hao DJ, He BR, et al. Posterior atlantoaxial fixation:
a review of all techniques. Spine J. 2015;15(10):2271–81. https://
doi.org/10.1016/j.spinee.2015.07.008. 15. Jones EL, Heller JG, Silcox DH, Hutton WC. Cervical pedicle
screws versus lateral mass screws. Anatomic feasibility and bio
mechanical comparison. Spine (Phila Pa 1976). 1997;22(9):977–
82. https://doi.org/10.1097/00007632-199705010-00009. 16. Patil PG, Turner DA, Pietrobon R. National trends in surgical
procedures for degenerative cervical spine disease: 1990–2000. Neurosurgery. 2005;57(4):753–8. discussion 753–758. 17. Dunlap BJ, Karaikovic EE, Park HS, Sokolowski MJ, Zhang
LQ. Load sharing properties of cervical pedicle screw-rod con
structs versus lateral mass screw-rod constructs. Eur Spine J. 2010;19(5):803–8. https://doi.org/10.1007/s00586-010-1278-0.i 18. Gottlieb S. Medical Devices; Orthopedic devices; classification
of posterior cervical Screw systems. Fed Reg. 2019;84(62).ii Mid 1992
The FDA acknowledged the off-label use of pedicle screws.
February
The FDA called for submission of pedicle screw system-related data. The panel members cited their knowledge and
clinical experiences with cervical screw systems, and the historical data for the safety
and efficacy of such devices. At the meeting’s conclusion, an unofficial vote favored the
designation of posterior cervical screws as Class II devices. The FDA proposed reclassifying rigid pedicle screw systems based on “new informa
tion.” At this time, rigid thoracolumbosacral pedicle screw systems were largely deemed
Class III devices.i The FDA proposed the classification of posterior cervical lateral mass and pedicle
screw systems as Class II. Posterior cervical screw systems were identified as those that
provided immobilization and stabilization of spinal segments in patients as an adjunct to
fusion for instabilities of the cervical spine, craniocervical junction, and/or cervicotho
racic junction. The proposal claimed that given cervical pedicle screw systems differed in
indication and anatomical location to thoracolumbosacral pedicle screw spinal systems,
they had to be classified separately from each other. The FDA suggested classifying thoracic, lumbar, and sacral rigid pedicle screw systems
adjuncts to fusions in treating degenerative disc disease and spondylolisthesis as Class II
devices. Posterior cervical screws remained unclassified. The FDA issued a final rule to reclassify posterior cervical screw systems as Class II,
with a continued requirement of premarket notification 510(k) to ensure reasonable safety
and effectiveness of the device. FDA likely could have significantly expedited this reclas
sification without compromising patient safety. between typical medical practice and FDA guidelines and
facilitate classifications that most accurately reflect the cur
rent regulatory needs for common medical devices. Overall, the regulatory history of cervical pedicle and lat
eral mass screws demonstrates how physicians and device
manufacturers can help to reduce the frequent dichotomy Author Contributions All authors contributed the writing and review
of this manuscript. 1 3 621 Therapeutic Innovation & Regulatory Science (2024) 58:614–621 surgery of the cervical spine. Spine. 2000;25(8):962–9. https://
doi.org/10.1097/00007632-200004150-00011. Data Availability No datasets were generated or analysed during the
current study. Data Availability No datasets were generated or analysed during the
current study. 12. Verma K, Boniello A, Rihn J. Emerging techniques for posterior
fixation of the lumbar spine. JAAOS - J Am Acad Orthop Surg. 2016;24(6):357. https://doi.org/10.5435/JAAOS-D-14-00378. References Fed Reg. 2014;79(218).i g
g p
9. May 22, Meeting of the Orthopaedic and Rehabilitation Devices
Panel of the Medical Devices Advisory Committee. 2013. 2013;(Classification Discussion Pedicle Screw Spinal Systems
(Certain Uses-Class III Indications for Use)). 28. Starmer E. Medical Devices; Orthopedic devices; classification
of posterior cervical Screw systems. Fed Reg. 2016;81(47). 10. Levine AM, Mazel C, Roy-Camille R. Management of frac
ture separations of the articular Mass using posterior cervi
cal plating. Spine. 1992;17(Supplement):S447–54. https://doi. org/10.1097/00007632-199210001-00018. Publisher’s Note Springer Nature remains neutral with regard to juris
dictional claims in published maps and institutional affiliations. Publisher’s Note Springer Nature remains neutral with regard to juris
dictional claims in published maps and institutional affiliations. g
11. Abumi K, Shono Y, Ito M, Taneichi H, Kotani Y, Kaneda K. Complications of pedicle screw fixation in reconstructive 1 1 3
|
https://openalex.org/W2972411502
|
http://www.scielo.br/j/rbsmi/a/pnG4yQkNZym7yCCD6zZJKZw/?lang=en&format=pdf
|
Portuguese
| null |
Prevalence and factors associated with excess weight in adolescents in a low-income neighborhood - Northeast, Brazil
|
Revista Brasileira de Saúde Materno Infantil
| 2,019
|
cc-by
| 6,683
|
Malaquias Batista Filho 8 Malaquias Batista Filho 8 Pedro Israel Cabral de Lira 4 https://orcid.org/0000-0002-1534-1620 1,2,4,5 Programa de Pós-Graduação em Nutrição. Departamento de Nutrição. Centro de Ciências da Saúde. Universidade Fe
1235 - Cidade Universitária, Recife, PE, 50670-901. E-mail: lizelda.araujo@yahoo.com.br 1,2,4,5 Programa de Pós-Graduação em Nutrição. Departamento de Nutrição. Centro de Ciências da Saúde. Universidade Federal de Pernambuco. Av. Prof. Moraes Rego, nº
1235 - Cidade Universitária, Recife, PE, 50670-901. E-mail: lizelda.araujo@yahoo.com.br 3 Departamento de Nutrição. Faculdade de Medicina. Universidade Federal do Rio Grande do Sul. Porto Alegre, RS, Brasil. 7 D
t
t
d E f
Á
d E f
S úd C l ti
C
t
d Ciê
i
d S úd
U i
id d F d
l d 3 Departamento de Nutrição. Faculdade de Medicina. Universidade Federal do Rio Grande do Sul. Porto Alegre, RS, Brasil. 7 Departamento de Enfermagem. Área de Enfermagem em Saúde Coletiva. Centro de Ciências da Saúde. Universidade Federal de Pernambuco. Recife, PE, Brasil. 6,8 Instituto de Medicina Integral Professor Fernando Figueira. Recife, PE, Brasil. 7 Departamento de Enfermagem. Área de Enfermagem em Saúde Coletiva. Centro de Ciências da Saúde. Universidade Federal de Pernamb
6,8 Instituto de Medicina Integral Professor Fernando Figueira. Recife, PE, Brasil. ORIGINAL ARTICLES ORIGINAL ARTICLES Key words Adolescent, Poverty, Overweight, Obesity, Prevalence http://dx.doi.org/10.1590/1806-93042019000300010 66
Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019
http://dx.doi.org/10.1590/1806-93042019000300010 Departamento de Enfermagem. Área de Enfermagem em Saúde Coletiva. Centro de Ciências da Saúde. Universidade Federal de Pernambuco. Recife, PE,
Instituto de Medicina Integral Professor Fernando Figueira. Recife, PE, Brasil. Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 Prevalence and factors associated with excess weight in adolescents in a low-
income neighborhood - Northeast, Brazil Jailma Santos Monteiro 5
https://orcid.org/0000-0002-4995-6172
Déborah Lemos Freitas 6
https://orcid.org/0000-0002-6068-8623
Weslla Karla Albuquerque Silva de Paula 7
https://orcid.org/0000-0002-0237-2663
Malaquias Batista Filho 8
https://orcid.org/0000-0002-1490-0590 Jailma Santos Monteiro 5
https://orcid.org/0000-0002-4995-6172
Déborah Lemos Freitas 6
https://orcid.org/0000-0002-6068-8623
Weslla Karla Albuquerque Silva de Paula 7
https://orcid.org/0000-0002-0237-2663
Malaquias Batista Filho 8
https://orcid.org/0000-0002-1490-0590 Weslla Karla Albuquerque Silva de Paula 7 Departamento de Nutrição. Faculdade de Medicina. Universidade Federal do Rio Grande do Sul. Porto Alegre, RS, Brasil.
Á 4,5 Programa de Pós-Graduação em Nutrição. Departamento de Nutrição. Centro de Ciências da Saúde. Universidade Federal de Pernambuco. Av. Prof
35 - Cidade Universitária, Recife, PE, 50670-901. E-mail: lizelda.araujo@yahoo.com.br Introduction of The Professor Fernando Figueira Integral
Medicine Institute, protocol number 3201-12, CAAE
n. 07246912.6.0000.5201, following the require-
ments in the National Health Council’s Resolution –
CNS 466/12. The nutritional and epidemiologic transition
observed in the past decades, corresponded to the
passage of the predominance of infectious/nutri-
tional diseases into a new, conceptually opposite
situation, that is, the wide prevalence of noncommu-
nicable diseases (NCDs), which has been growing
across the world.1 In Brazil, the phenomenon was
constituted as a characteristic model of morbimor-
tality, in which infectious/nutritional diseases in
quick decline and NCDs in a much more intense
expansion rate coexist.2 The sample calculation for this study considered
as a reference a universe of 1,157 adolescents, regis-
tered in both units of the Family Health Strategy
(FHS), which assist the families from the commu-
nity, according to the Primary Care Information
System of the Municipal Health Secretariat of
Recife, PE, in 2013. For the calculation, the
StatCalc-Epi Info version 6.04 was used, considering
a prevalence of 16.2% of excess weight for the age
group of 10-19 years in the Metropolitan Region of
Recife, PE, in 2006.11 Because of the demographic
and nutritional transition which occurred between
2006 and 2014, a 20% increase was estimated,
resulting in an adjusted prevalence of approximately
19%. An error of ±5 percentage points and a confi-
dence level of 95% were considered, which numbers
a minimum initial sample of 224 individuals, having
all participants been randomly chosen, considering
the whole amount of individuals. As a result of these transformations, the
combined prevalence of overweight/obesity (excess
weight) is becoming evident in all economic
classes,3 especially among adolescents.4 In this age
group, excess weight may result from the influence
of various factors, among which, biological, beha-
vioral, psychological, and socioeconomic factors. Body changes in this period,5 as well as concerns on
the body image, which includes how adolescents
perceive their own body,6 make adolescence a cri-
tical period for the development of nutritional disor-
ders. In this stage, a sedentary lifestyle itself is an
independent risk factor for the development of
NCDs.7 From the socioeconomic perspective,
obesity is more frequent among low-income indivi-
duals with low educational attainment and less privi-
leged occupational status, either in developed or
developing countries.8,9 Since this study aimed to analyze the variables
associated with excess weight, calculations were
made to estimate the differences in the set of inde-
pendent variables. Abstract Objectives: to study the prevalence of excess weight and associated factors among
adolescents from a low-income neighborhood located in the city of Recife, Pernambuco. Methods: cross-sectional study, in which behavioral, socioeconomic and demographic
information was collected from June to December 2014. Excess weight was calculated based
on body mass index for age and the cut-off points, by the World Health Organization (2007). To analyze associations between predictor variables and the outcome, multivariate data
analysis was performed following the Poisson Regression (Prevalence Ratio - PR) with their
respective 95% confidence intervals (95%CI). Results: twenty-five adolescents participated in the study, with a prevalence of 36.4% of
excess weight: 20.4% overweight (95%CI=15.1-25.7) and 16.0% obesity (95%CI= 11.2-
20.8), predominantly in female gender (42.5%; p=0.031). The outcome was associated with
internet access (PR=1.20; 95%CI=1.01-1.43), the number of people in the family (PR= 1.12;
95%CI=1.01-1.28) and screen time (PR=1.13; 95%CI=1.01-1.27), but only in male gender. Conclusions: the prevalence found was higher than that of other national researches,
especially for the female gender. In the male gender, not having internet access, a lesser
number of family members and a longer screen time proved to be factors associated with
being excess weight. Key words Adolescent, Poverty, Overweight, Obesity, Prevalence This article is published in Open Access under the Creative Commons Attribution
license, which allows use, distribution, and reproduction in any medium, without
restrictions, as long as the original work is correctly cited. 661 Barbosa LMA et al. Introduction In order to do so, a prevalence
ratio of 2.5 was estimated, considering the ratio 1:1
(112:112) for a prevalence of 10% of not exposed
and 25% of exposed, to a confidence level of 95%
(1-alpha) and power of study of 80% (1-beta). Therefore, identifying excess weight in poor
areas, as well as psychological, behavioral, and
economic aspects associated with the problem,
might help to understand its effects in adolescence
and in plans for future interventions in the collective
health field. Regarding this context, this research’s
aim was to determine the prevalence of excess
weight and associated factors among adolescents
from a low-income neighborhood located in the city
of Recife, Pernambuco, Northeastern Brazil. Data collection occurred between June and
December 2014. First, the FHS were visited to
present the research to Community Health Workers
(CHW). Second, all homes where there were adoles-
cents in the families were visited by the previously
trained research team, followed by the CHW from
the FHS. If there were more than one adolescent in
the family, data of at least one adolescent were
collected. All interviews were performed in the inter-
viewees’ homes, except for anthropometric data
collection, which occurs in a health unit on a previ-
ously-scheduled day. The adolescents were informed
of the research aim, as well as the adopted parame-
ters. Adolescents of both genders were included,
aged between 10-19 years, residents in the commu-
nity. The ones who had cognitive difficulties to
answer the questionnaires, functional limitations to
perform the anthropometric assessment, or were
pregnant were excluded. Data were only collected
after authorization by the Committee for Ethics and
signature of the Free and Informed Consent. adolescents aged 5-19 years.15 through the application of structured questionnaires,
previously tested and codified, applied to the adoles-
cents and their guardians, which were arranged as:
demographic (age and gender), socioeconomic
(socioeconomic status, internet access, number of
rooms, number of family members, and occupational
status), house features (type of construction and
floor), behavioral (use of video game/cell phone,
computer, television, level of physical activity,
screen time along the week and weekend), and lastly,
psychological variables (personal satisfaction and
self-perception of weight). These variables were
subjectively assessed through the following ques-
tions: “Do you consider yourself happy?” and “How
do you consider yourself regarding your weight?”. For the classification of the anthropometric
indexes, we considered the following cut-off scores:
low weight= <-2 scores-z; eutrophy= ≥-2 scores-z to
<+1 score-z; overweight= ≥+1 score-z and <+2
scores-z; and obesity= ≥+2 scores-z. For analysis
purposes, the nutritional status was categorized as
follows: without excess weight (low weight and
eutrophy) and with excess weight (overweight and
obesity), which is the outcome variable. Data were entered into the program Epi Info
version 3.5.4., designed for Windows. The analyses
were carried out with the softwares Statistical
Package for the Social Sciences version 1316 and
Stata version 1417. For the descriptive analysis,
Pearson’s chi-squared statistical tests were used for
nominal variables, chi-squared test for trend for
ordinal variables, and Fisher exact test for variables
whose frequency was lower than five. Poisson
regression was used to calculate the prevalence
ratios and their respective confidence intervals of
95% for univariate and multivariate. For the latter,
Poisson regression was applied through gender-stra-
tified evaluation, besides the total number of adoles-
cents. The variables which showed significance level
p<0.20 in the univariate analysis were included in
the multivariate analysis, which followed the
analysis model: on the first level, demographic and
socioeconomic variables; on the second level, the
variables from the first level which presented p<0.20
and the psychological and behavioral variables,
controlled by variables on the first level. The consi-
dered statistical significance value was p≤0.05. adolescents aged 5-19 years.15 For the socioeconomic classification, we used
the tool of the Brazilian Association of Research
Enterprises (ABEP – Portuguese acronym), which
includes ownership of household goods and the head
of the family’s educational attainment level.12
Following ABEP’s classification, the adolescents
were separated into the following economic cate-
gories, according to the gross average household
monthly income in reais (Brazilian currency): B1,
B2, and C1 (R$1,865 to R$6,006); C2 (R$1,277 to
R$1,865); D and E (<R$1,277). Since the study was
performed in a low-income community, no indi-
vidual belonged to class A (>R$6,006). g
(
)
The tool used to measure the level of physical
activity was the International Physical Activity
Questionnaire (IPAQ), in its short form.13 To calcu-
late the screen time, we collected time in hours and
minutes that the adolescent spent on the video game
or cell phone, computer and television on weekdays
and weekends. The calculation of time was
converted into hours separately for weekdays and
weekends and was analyzed as two independent
variables. Those whose screen time was longer than
two hours per day were classified as “exposed” to
excessive screen time.14 The variable of self-percep-
tion of weight was subjectively assessed by the
adolescent through the question: “How do you
consider yourself regarding your weight?”, with
three possible answers: “skinny”, “average”, or
“fat”. Methods The research consisted in a cross-sectional study,
whose participants derive from the research entitled
“Saúde, nutrição e serviços assistenciais numa
população favelada do Recife: um estudo baseline”,
developed in Coelhos Community, a subnormal
urban agglomeration10 situated in a poor area in the
suburbs of Recife, Pernambuco. This census-
purposed survey comprehended 4,739 individuals
out of nearly 7,400 inhabitants. The research was
approved by the Committee for Ethics in Research The independent variables were collected Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 662 Excess weight in low-income adolescents Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 Discussion The results in this study corroborate the universal-
ization of the epidemiologic transition, scientifically
known in developed countries to be an event that has
begun around 50 years ago,18,19 and in Brazil and
Latin America, in the past four decades,2 also gene-
rally in the different socioeconomic status in the
urban spaces. In general, subnormal urban agglo-
meration is home to families who live under envi-
ronmental and socioeconomic conditions that are
very precarious, and should present, as a proba-
bilistic scenario, fundamentally unfavorable situa-
tions, specifically including the prevalence of nutri-
tional aggravations.10 However, prevalence of
excess weight in the total population (36,4%) was
higher than the national average,4 revealing the
epidemic levels of the problem, which corresponds
to situations particular to developed countries, such
as the United States, Canada and the United
Kingdom.18,19 This was an important finding that
should be deeply analysed as a generic matter of the
transition process and as a particularity of the urban
populations who live in places of great poverty. Table 1 shows the gender-stratified descriptive
analysis. It can be observed that the variables
number of rooms, usage of video game/cell phone,
television, level of physical activity, type of home
construction and floor are statistically different when
compared to gender. Regarding the male adoles-
cents, most of them lived in homes with more than
four rooms (73.5%, p=0.002), used video game/cell
phone (73.5%, p=0.001) and lived in masonry
houses (94.9%, p=0.018) with ceramic floors
(66.3%, p=0.023). On the other hand, the girls
watched more television (98.4%, p=0.009), were
more irregularly active (33.9%, p<0.001) and lived
in cardboard, canvas, or wood houses (15%,
p=0.018) with wood floor (48.8%, p=0.023). (Table
1) When compared to other cities in Northeastern
Brazil, the prevalence found was higher than what
was identified in the metropolitan area of Recife,
PE,11 (16.2%) and other cities, such as Salvador,
BA,20 (15.7%), Maceió, AL,21 (13.8%), Fortaleza,
CE,22 (24%), João Pessoa, PB,23 (27.2%) and
Imperatriz, MA,24 (16.9%). Nevertheless, national
studies on prevalence of excess weight in low-
socioeconomic-status adolescents are still limited,
which hinders a more conclusive analysis of aggra-
vation in those populations.3 Table 2 shows associations of the excess weight
with the independent variables assessed in the
univariate analysis. Results In the total population of adolescents, the
authors found excess weight prevalence of 63.4%,
out of which, 20.4% (CI95%=15.1-25.7) were over-
weight and 16.0% (CI95%=11.2-20.8) were obese. The sample was predominantly constituted of
adolescents in the socioeconomic class C2 (41.3%;
CI95%=35.3-48.3), who were not working (65.6%;
CI95%=59.2-71.9) and had internet access (78.4%;
CI95%=72.9-83.9). Furthermore, the authors
observed that 61.8% lived in homes with more than
four rooms (CI95%=55.4-68.2), 96.8% considered
themselves happy (CI95%=94.4 – 99.1) and 50.9%
considered themselves in average weight for their
age (CI95%=44.2 – 57.6). Regarding the total
number of family members, there was a homoge-
neous distribution: 52.7% (CI95%= 46.1-59.3)
belonged to families with less than four people and
47.3% (CI95%=40.7-53.9) to families with more
than four. The losses by lack of information occurred
in the variable number of family members (three
losses). (Not-shown data). As the gender-stratified multivariate analysis was
carried out, we observed that among male adoles-
cents, not having internet access, having less than
four family members, and spending more than two
hours per day on screen on the weekend were factors
that increased the probability of excess weight
occurence in 20%, 12%, and 13%, respectively, even
after the adjustments in the association of the
outcome with the other exploratory variables. (Table
3) Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 Results A number of 1,446 residences were visited in the
community. There were exactly 1,157 adolescents
registered in both ESFs, among which, 958 answered
questionnaires of demographic data and 342
answered questionnaires of psychological and
behavioral data. As the anthropometry occurred on a
different day at the health unit, it had low engage-
ment and hence, a number of only 225 adolescents
were present, representing the study’s final sample,
which corresponds to 19.4% of the total population. In order to verify that the socioeconomic condition
of the excluded individuals in the study (n=733) did
not differ from the included ones’ condition (n=225),
both were compared regarding occupational status. No statistically significant difference was found
(p=0.945). The measurements of weight and height were
conducted twice, obtained with a digital scale by
SECA® 876, with capacity of up to 250 kg and scale
of 100 grams, and a mobile stadiometer (Altura
exata Ltda) with 1mm precision, respectively. To
evaluate the nutritional status, the criteria of the
World Health Organization (WHO) were adopted
through the evaluation of Body Mass Index for age
(BMI-for-age) according to gender, for children and From the 225 adolescents participating in the
study, 98 (43.6%) were male and 127 (56.4%) 663 Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 Barbosa LMA et al. female, with an average age of 14.74 years
(SD=2.86). In the total population of adolescents, the
authors found excess weight prevalence of 63.4%,
out of which, 20.4% (CI95%=15.1-25.7) were over-
weight and 16.0% (CI95%=11.2-20.8) were obese. The sample was predominantly constituted of
adolescents in the socioeconomic class C2 (41.3%;
CI95%=35.3-48.3), who were not working (65.6%;
CI95%=59.2-71.9) and had internet access (78.4%;
CI95%=72.9-83.9). Furthermore, the authors
observed that 61.8% lived in homes with more than
four rooms (CI95%=55.4-68.2), 96.8% considered
themselves happy (CI95%=94.4 – 99.1) and 50.9%
considered themselves in average weight for their
age (CI95%=44.2 – 57.6). Regarding the total
number of family members, there was a homoge-
neous distribution: 52.7% (CI95%= 46.1-59.3)
belonged to families with less than four people and
47.3% (CI95%=40.7-53.9) to families with more
than four. The losses by lack of information occurred
in the variable number of family members (three
losses). (Not-shown data). female, with an average age of 14.74 years
(SD=2.86). Discussion It shows higher excess weight
prevalences among female adolescents (42.5%,
p=0.029), those who used computer (49.3%,
p=0.007), those who were irregularly active (49.2%,
p=0.016) and those who perceive themselves as “fat”
(78.2%, p<0.001). (Table 2) By including variables in the multivariate model,
self-perception of weight was the only which kept
the association with the excess weight occurrence in
both genders in an independent way. From the total
population, the adolescents who considered them-
selves “fat” had an excess weight prevalence of 61%
higher than the ones who considered themselves
“skinny”, regardless of the other variables analyzed. The etiology of excess weight has been shown as
complex and multicausal.3 In this study, the possible
sociodemographic, behavioral and psychological
determinations. Excess weight was more prevalent
in adolescents, similarly to previous studies
found.11,20,23 Although data on sexual maturation
have not been collected, the literature states that the
highest prevalence rates for excess weight in girls 664 Excess weight in low-income adolescents Distribution of demographic, socioeconomic, behavioral, psychological and nutritional status of adolescents according
to gender. Coelhos Community – Recife, PE, 2014. a p<0.05 for Pearson’s chi-squared test, b p<0.05 for chi-squared test for trend, c p<0.05 Fisher exact test. Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019
665 a p<0.05 for Pearson’s chi-squared test, b p<0.05 for chi-squared test for trend, c p<0.05 Fisher exact test. Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 ju Discussion Variables
Age range
10 to 14 years
15 to 19 years
Socioeconomic Class
B1, B2, C1
C2
D, E
Internet access
Yes
No
Number of rooms
≤4
>4
Number of family members
≤4
>4
Nutritional status
Underweight
Eutrophy
Overweight
Obesity
Type of house construction
Masonry / brick + mud
Cardboard / Canvas / Wood
House’s floor type
Ceramics
Wood / cement / other
Video game or cell phone usage
Yes
No
Computer usage
Yes
No
Television usage
Yes
No
Physical activity level
Irregularly active
Active
Very active
Screen time on weekdays
<2 hours / day
≥2 hours / day
Screen time on weekends
<2 hours / day
≥2 hours / day
Self-perception of weight
“Skinny”
“Average”
“Fat”
0.318
0.934
0.943
0.002a
0.703
0.031c
0.018a
0.023a
0.001a
0.078
0.009a
<0.001b
0.379
0.158
0.083
55
72
33
53
41
99
28
60
67
65
61
2
71
31
23
108
19
65
62
65
62
82
45
125
2c
43
70
14
11
116
29
98
27
65
35
Male
n % n %
p*
43.3
56.7
26.0
41.7
32.3
78.0
22.0
47.2
52.8
51.6
48.4
1.6
55.9
24.4
18.1
85.0
15.0
51.2
48.8
51.2
48.8
64.6
35.4
98.4
1.6
33.9
55.1
11.0
8.7
91.3
22.8
77.2
21.3
51.2
27.6
49
49
25
41
32
76
22
26
72
52
44
6
64
15
13
93
5
65
33
72
26
74
24
89
9
18
47
33
12
86
15
83
30
48
20
50.0
50.0
25.5
41.8
32.7
77.6
22.4
26.5
73.5
54.2
45.8
6.1
65.3
15.3
13.3
94.9
5.1
66.3
33.7
73.5
26.5
75.5
24.5
90.8
9.2
18.4
48.0
33.7
12.2
87.8
15.3
84.7
30.6
49.0
20.4
Female Distribution of demographic, socioeconomic, behavioral, psychological and nutritional status of adolescents according
to gender. Coelhos Community – Recife, PE, 2014. Distribution of demographic, socioeconomic, behavioral, psychological and nutritional status of adolescents according
to gender. Coelhos Community – Recife, PE, 2014. or trend, c p<0.05 Fisher exact test. quared test, b p<0.05 for chi-squared test for trend, c p<0.05 Fisher exact test. Discussion 0.318
0.934
0.943
0.002a
0.703
0.031c
0.018a
0.023a
0.001a
0.078
0.009a
<0.001b
0.379
0.158
0.083
55
72
33
53
41
99
28
60
67
65
61
2
71
31
23
108
19
65
62
65
62
82
45
125
2c
43
70
14
11
116
29
98
27
65
35
Male
n % n %
p*
43.3
56.7
26.0
41.7
32.3
78.0
22.0
47.2
52.8
51.6
48.4
1.6
55.9
24.4
18.1
85.0
15.0
51.2
48.8
51.2
48.8
64.6
35.4
98.4
1.6
33.9
55.1
11.0
8.7
91.3
22.8
77.2
21.3
51.2
27.6
49
49
25
41
32
76
22
26
72
52
44
6
64
15
13
93
5
65
33
72
26
74
24
89
9
18
47
33
12
86
15
83
30
48
20
50.0
50.0
25.5
41.8
32.7
77.6
22.4
26.5
73.5
54.2
45.8
6.1
65.3
15.3
13.3
94.9
5.1
66.3
33.7
73.5
26.5
75.5
24.5
90.8
9.2
18.4
48.0
33.7
12.2
87.8
15.3
84.7
30.6
49.0
20.4
Female a p<0 05 for Pearson’s chi-squared test b p
Age range
10 to 14 years
15 to 19 years
Socioeconomic Class
B1, B2, C1
C2
D, E
Internet access
Yes
No
Number of rooms
≤4
>4
Number of family members
≤4
>4
Nutritional status
Underweight
Eutrophy
Overweight
Obesity
Type of house construction
Masonry / brick + mud
Cardboard / Canvas / Wood
House’s floor type
Ceramics
Wood / cement / other
Video game or cell phone usage
Yes
No
Computer usage
Yes
No
Television usage
Yes
No
Physical activity level
Irregularly active
Active
Very active
Screen time on weekdays
<2 hours / day
≥2 hours / day
Screen time on weekends
<2 hours / day
≥2 hours / day
Self-perception of weight
“Skinny”
“Average”
“Fat” 665 Barbosa LMA et al. Excess weight in adolescents according to demographic, socioeconomic, behavioral and psychological variables. Coelhos Community – Recife, PE, 2014. Excess weight in adolescents according to demographic, socioeconomic, behavioral and psychological variables. Coelhos Community – Recife, PE, 2014. *Excess weight= overweight + obesity, a gross PR= gross Prevalence Ratio, b CI95%= 95% Confidence Interval. Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 Discussion Variables
Gender
Male
Female
Age range
15 to 19 years
10 to 14 years
Socioeconomic Class
D, E
C2
B1, B2, C1
Internet access
Yes
No
Number of rooms
>4
≤4
Number of family members
>4
≤4
Type of house construction
Masonry / brick + mud
Cardboard / Canvas / Wood
House’s floor type
Ceramics
Wood / cement / other
Video game or cell phone usage
Yes
No
Computer usage
Yes
No
Television usage
Yes
No
Physical activity level
Very Active
Active
Irregularly active
Screen time on weekdays
<2 hours / day
≥2 hours / day
Screen time on weekends
<2 hours / day
≥2 hours / day
Self-perception of weight
“Skinny”
“Average”
“Fat”
0.029
0.978
0.529
0.112
0.185
0.136
0.314
0.506
0.407
0.007
0.501
0.016
0.092
0.738
<0.001
28
54
43
39
25
34
23
59
23
46
36
33
48
71
11
45
37
47
35
48
34
3
79
13
39
30
5
77
16
66
4
35
43
Total
n % n % Gross PRa
CI95%b
p
28.6
42.5
35.5
37.5
34.2
36.2
39.7
33.7
46.0
33.1
41.9
31.4
41.0
35.3
45.8
34.6
38.9
34.3
39.8
30.8
49.3
27.3
36.9
27.7
33.3
49.2
21.7
38.1
36.4
36.5
7.0
31.0
78.2
98
127
121
104
73
94
59
175
50
139
86
108
117
201
24
130
95
137
88
156
69
11
214
47
117
61
23
202
44
181
57
113
55
43.6
56.4
53.8
46.2
32.4
41.8
25.8
77.8
22.2
61.8
38.2
47.3
52.7
89.3
10.7
57.8
42.2
60.9
39.1
69.3
30.7
4.9
95.1
20.9
52.0
27.1
10.2
89.8
19.6
80.4
25.3
50.2
24.4
With excess weight *
1
1.11
1
1.01
1
1.01
1.04
1
1.09
1
1.06
1
1.07
1
1.08
1
1.03
1
1.04
1
1.14
1
1.07
1
1.04
1.17
1
1.13
1
0.98
1
1.22
1.65
1.01-1.21
0.91-1.10
0.91-1.13
0.92-1.17
0.98-1.22
0.97-1.17
0.98-1.18
0.93-1.24
0.94-1.13
0.95-1.14
1.04-1.26
0.87-1.33
0.93-1.18
1.02-1.33
0.98-1.31
0.87-1.10
1.11-1.34
1.52-1.83 Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 666 bLevel 1= adjusted to the other variables on this level, cLevel 2= adjusted by variables on level 1. Discussion Along with that, the modern envi-
ronment cooperates for teenagers to opt for watching
television instead of doing sports, as they use the
computer or cell phone to talk to their friends and
play video games instead of engaging in play at
school or on the street.28,29 can be partially explained by the greater vulnerabilty
of the female organism to accumulate body fat,
which occurs through the sexual hormones in ages
near puberty.5 The lack of association between socioeconomic
status and excess weight was a striking finding, since
the studied area has expressive economic vulnera-
bility, has high prevalence rates for obesity, and that
is indicated in the studies.8,9 However, it is worth
remarking that the majority of the studied adoles-
cents were in classes C2, D and E, constituting a
homogeneous group among the assessed families. In
those homogeneous communities with access to
essential consumer goods, the traditional indicators
for assessing socioeconomic condition have been
shown as not much sensitive to detect differences
between the groups, while other more recent alterna-
tive methods, such as internet access, displayed more
association with the socioeconomic condition. In this investigation, not having internet access
was an associated factor to excess weight among
male adolescents. A study25 states that low-income
populations are more likely to experience social
challenges, including limited internet access and
devices with connection to it, which, for that status,
makes that variable represent more the socioeco-
nomic status than the behavioral aspect. This way,
not having internet access at home would mean
having lower financial condition and less equitable
access to social opportunities,25 which would, then,
make those teenagers to be more exposed to irreg-
ular access to healthcare25,26 and excess weight.8
This result is in consonance with Mayen et al.8
systematic review, from which the authors have
concluded that the best socioeconomic condition and
the urban area were associated with higher food
quality, diversity and healthier dietary patterns, then,
constituting a protection factor for the occurence of
NCDs, among which is obesity. Self-perception of weight was independently
associated with the occurrence of excess weight in
both genders, similarly to what has been found in
Pereira et al.30 study, suggesting that they were
aware of their nutritional status regardless of other
behavioral and socioeconomic factors. Although
most of the adolescents had an adequate perception,
that data deserves caution to be interpreted, as it is a
subjective analysis. Discussion PR (CI95%)a
p
Gross RP (CI95%)a
Adjusted PR (CI95%)a
p
Gross RP (CI95%)a
Adjusted PR (CI95%)a
p
1
00-1.20)
1
97-1.22)
1
93-1.12)
1
98-1.17)
1
97-1.17)
1
92-1.13)
94-1.19)
1
98-1.27)
-
-
1
11-1.34)
48-1.78)
0.052
0.126
0.617
0.142
0.157
0.229
0.086
-
-
< 0.001
-
-
1
1.17 (0.99-1.38)
-
-
1
1.13 (0.99-1.30)
1
1.13 (0.97-1.34)
1
0.96 (0.82-1.11)
1.30 (1.08-1.56)
-
-
1
1.17 (0.99-1.38)
1
1.23 (1.09-1.38)
1.64 (1.44-1.88)
-
-
1
1.20 (1.01-1.43)
-
-
1
1.12(1.01-1.28)
1
1.09 (0.94-1.25)
1
0.97 (0.84-1.12)
1.13 (0.95-1.34)
-
-
1
1.13 (1.01-1.27)
1
1.21 (1.07-1.37)
1.50 (1.30-1.73)
-
-
0.037
-
-
0.049
0.244
0.207
-
-
0.048
< 0.001
-
-
-
-
1
1.10 (0.98-1.24)
-
-
1
1.12 (0.99-1.27)
-
-
-
-
-
1
0.91 (0.79-1.04)
1
1.20 (1.05-1.38)
1.64 (1.45-1.87)
-
-
-
-
1
1.10 (0.98-1.24)
-
-
1
1.05 (0.94-1.18)
-
-
-
-
-
1
0.92 (0.81-1.03)
1
1.18 (1.03-1.36)
1.60 (1.41-1.84)
-
-
-
-
0.105
-
-
0.349
-
-
-
-
-
0.165
< 0.001 ght in Barbosa LMA et al. In this research, we measured the time the
teenagers spent on video games or cell phone,
computer and television, on weekdays and wee-
kends. These variables together reveal screen time,
considered as a marker for sedentary behaviour in
children and adolescents. When that time is longer
than two hours per day, it is a risk factor for diseases
related to obesity.14 After the adjustments for the
confusion variables, screen time longer than two
hours per day on weekends appeared as a factor
associated to excess weight in male adolescents. The
long time dedicated to sedentary leisure activities is
a reality for adolescents and appears in national28
and also international29 studies. Concern with
violence is a social factor that collaborates for
teenagers to seek fun inside their homes, making
them sedentary. Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 Discussion The literature recommends the
use of tools, such as the Figure Rating Scale and
questionnaires, because they aim to identify discre-
pancies between real body and desired body,6 a
methodology that has not been applied to this study. This research contributes to the existing litera-
ture for the following strong points: (a) there are few
studies in the national and international literature on
prevalence and factors associated to excess weight
in low-income adolescents; (b) in face of the lack of
studies in poverty areas, establishing the magnitude
of the problem from a perspective of primarily
preventive interventions in the collective health field
is fundamental; (c) the measures were taken by using
suitable and reliable techniques performed by previ-
ously trained interviewers; (d) the variables were
adjusted through multivariate analysis techniques
adequate for the research design. Therefore, not having internet access and having
less than four people in the family were associated
with higher probability of excess weight among male
adolescents, which demonstrates that the difference
in the prevalence of overweight between genders,
besides a biological matter, can be influenced by a
socioeconomic difference between genders. Concerning family size, Ochiai et al.26 argue that
it can influence the nutritional status of low-income
individuals: the more members in the family, the
lower the probability of obesity. That occurs due to
the existence of financial difficulties to access and
share foods among relatives, promoting lower total
individual calorie intake and, consequently, no
excess weight gain.27 On the other hand, there might be some metho-
dological limitations that should be examined for the
interpretation and validity of the results: (a) the
absence of information on the sexual maturation
stage; (b) some information, such as hours of seden-
tary activity and physical activity, was mentioned by Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 668 Excess weight in low-income adolescents the adolescents themselves and is subjected to
memory bias; (c) there might have been reverse
causality bias, due to transversality in the study. proposed intersectoral actions must ensure food
security for the families, the reduction of social
inequalities, incentive to change of lifestyle and the
adolescents’ awareness about their participation in
the process of producing their own health. In face of
the scarcity of works on low-income communities, it
is necessary to carry more studies with those popula-
tions. References 1. Afshin A, Forouzanfar M, Reitsma M, Sur P, Estep K, Lee
A, Marczak L, Mokdad AH, et al. Health Effects of
Overweight and Obesity in 195 Countries over 25 Years. N
Engl J Med. 2017; 377 (1): 13–27. 7. Vasconcelos F, Seabra A, Katzmarzyk PT, Kraemer-Aguiar
LG, Bouskela E, Farinatti P. Physical activity in overweight
and obese adolescents : systematic review of the effects on
physical fitness components and cardiovascular risk factors. Sports Med. 2014; 44 (8): 1139–52. 2. Batista Filho M, Rissin A. A transição nutricional no Brasil:
tendências regionais e temporais. Cad Saúde Pública. 2003;
19 (Supl.1): S181–S91. 8. Mayén A-L, Marques-Vidal P, Paccaud F, Bovet P, Stringhini
S. Socioeconomic determinants of dietary patterns in low-
and middle-income countries: a systematic review. Am J
Clin Nutr. 2014; 100 (6): 1520–31. 3. Niehues JR, Gonzales AI, Lemos RR, Bezerra PP, Haas P. Prevalence of overweight and obesity in children and
adolescents from the age range of 2 to 19 years old in
Brazil. Int J Pediatr. 2014; (583207): 1-7. 9. Popkin BM, Slining MM. New dynamics in global obesity
facing low- and middle-income countries. Obes Rev. 2013;
14 (2): 11–20. 4. Bloch KV, Klein CH, Szklo M, Kuschnir MCC, Abreu G de
A, Barufaldi LA, Veiga GV, Schaan B, Silva TLN. ERICA:
prevalências de hipertensão arterial e obesidade em adoles-
centes brasileiros. Rev Saúde Pública. 2016; 50 (Supl. 1):
1–13. 10. IBGE (Instituto Brasileiro de Geografia e Estatística). Censo demográfico: Aglomerados subnormais – infor-
mações territoriais. Rio de Janeiro: 2010. p. 1-251 11. Leal VS, Lira PIC, Oliveira JS, Menezes RCE, Sequeira
LAS, Neto MAA, Andrade SLLS, Batista Filho M. Excesso
de peso em crianças e adolescentes no Estado de
Pernambuco, Brasil: prevalência e determinantes. Cad
Saúde Pública. 2012; 28 (6): 1175–82. 5. Daniels SR , Arnett DK , RH Eckel , SS Gidding , Hayman
LL , Kumanyika S , Robinson TN , BJ Scott , St Jeor S ,
Williams CL. Overweight in children and adolescents:
Pathophysiology, consequences, prevention, and treatment. Circulation. 2005; 111 (15): 1999–2012. 12. ABEP (Associação Brasileira de Empresas de Pesquisa). Dados com base no Levantamento Sócio Econômico 2014
– IBOPE [Internet]. 2014. [acesso em 19 mar 2018]. Disponível em: http://www.abep.org/Servicos/Download. aspx?id=01 6. Garcia DM, Mekitarian Filho E, Gilio AE, Lotufo JPB, Lo
DS. Estado nutricional, autopercepção do estado nutricional
e experimentação de drogas lícitas em adolescentes. Rev
Paul Pediatr. Discussion The prevalence of excess weight in adolescents
from Coelhos community was higher than what was
found in previous national studies. In that set of
cases, behavioral and socioeconomic factors, and
excess weight combined in different ways between
genders: the factors that combined with excess
weight for the male gender were not having internet
access, the smallest number of people in the family
and screen time longer than two hours per day on
weekends, and for both genders, only self-perception
of body weight. The absence of association with the
levels of physical activity regardless of the excess
weight suggests the need for new studies concerning
these variables in low-income communities, since
the literature has been displaying those associations. Authors’ contributions Barbosa LMA - bibliographic survey, data analysis
and interpretation, article writing, approval of the
final version to be submitted. Arruda IKG, Lira PIC
and Paula WKAS - study design and conception,
data analysis and interpretation, critical review of
relevant intellectual content, approval of the final
version to be submitted. Canuto R - Data analysis
and interpretation, critical review of relevant intel-
lectual content, approval of the final version to be
submitted. Monteiro JS, Freitas DL and Batista Filho
M - study design and conception, data analysis and
collection, approval of the final version to be
submitted. All authors approved the final version of
the manuscript. This investigation proved to be important for
contributing with new findings in the national scope,
bringing data that can serve as reflection for other
similar populations. The identified reality provides
means for interventions in Family Health Units
which can significantly improve life quality and
nutritional status of the individuals in the commu-
nity, aiming to promote adolescent health. The References 2015; 33 (3): 332–9. Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 669 Barbosa LMA et al. 13. Matsudo S, Araújo T, Matsudo V, Andrade D, Andrade E,
Oliveira LC, Braggion G. Questionário Internacional de
Atividade Física (IPAQ): Estudo de Validade e
Reprodutibilidade no Brasil. Rev Bras Ativ Fis Saúde. 2012; 6 (2): 5–18. 23. Lima RPA, Pereira DC, Luna RCP, Gonçalves MCR, Lima
RT, Batista Filho M, Filizola RG, Moraes RM, Asciutti
LSR, Costa MJC. BMI, overweight status and obesity
adjusted by various factors in all age groups in the popula-
tion of a city in northeastern Brazil. Int J Environ Res
Public Health. 2015; 12 (4): 4422–38. 14. SBP (Sociedade Brasileira de Pediatria). Obesidade na
infância e adolescência – Manual de Orientação. Departamento Científico de Nutrologia. 2 ed. São Paulo:
SBP; 2012. p.142. 24. Nascimento-Ferreira MV, Moraes ACF, Carvalho HB,
Moreno LA, Carneiro ALG, Reis VMM, Torres-Leal FL. Prevalence of cardiovascular risk factors, the association
with socioeconomic variables in adolescents from low-
income region. Nutr Hosp. 2015; 31 (1): 217–24. 15. Onis M de, Adelheid W Onyango, Borghi E, Siyam A,
Nishidaa C, Siekmanna J. Development of a WHO growth
reference for school-aged children and adolescents. Bull
World Heal Organ. 2007; 85(9): 660–7. 25. Katz VS, Gonzalez C, Clark K. Digital Inequality and
Developmental Trajectories of Low-income, Immigrant,
and Minority Children. Pediatrics. 2017; 140 (Suppl. 2):
S132–S8. 16.Statistical Package for the Social Sciences. SPSS for
Windows
13. Software. Disponível
em:
https://www.ibm.com/br-pt/products/spss-statistics 26. Ochiai H, Shirasawa T, Ohtsu T, Nishimura R, Morimoto
A, Obuchi R, Hoshino H, Tajima N, Kokaze A. Number of
siblings, birth order, and childhood overweight: a popula-
tion-based cross-sectional study in Japan. BMC Public
Health. 2012; 12 (766): 1-7. 17.Stata
versão
14. Software. Disponível
em:
https://www.stata.com/support/faqs/resources/citing-soft-
ware-documentation-faqs/ 18. Conference of european statisticians recommendations for
the 2010 censuses of population and housing [Internet]. Geneva: United Nations. 2006. [cited 2018 mar 24]. p. 200. Available
from:
https://www.unece.org/fileadmin/
DAM/stats/publications/CES_2010_Census_Recommendat
ions_English.pdf 27. Mosli RH, Miller AL, Peterson KE, Kaciroti N, Rosenblum
K, Baylin A, Lumeng JC. Birth order and sibship composi-
tion as predictors of overweight or obesity among low-
income 4- to 8-year-old children. Pediatr Obes. 2017; 11
(1): 40–6. 28. Tassitano RM, Barros MVG, Tenório MCM, Bezerra J,
Hallal PC. Prevalência e fatores associados ao sobrepeso e
à obesidade em adolescentes, estudantes de escolas de
Ensino Médio de Pernambuco, Brasil. Rev. Bras. Saúde Mater. Infant., Recife, 19 (3): 661-670 jul. / set., 2019 ______________
Received on August 10, 2018
Final version presented on May 07, 2019
Approved on June 21, 2019 Received on August 10, 2018 References Cad de Saúde
Pública. 2009; 25 (12): 2639–52. 19. Dick P. The census of Canada: the dwelling classification
study. In: Joint Statistical Meetings. Proceedings. Alexandria: United States: ASA ASA; 2002. p. 782-7. 20. Marques CDF, Silva R de CR, Machado MEC, Santana
MLP de, Cairo RCA, Pinto EJ , Maciel LOR, Silva LR. The
prevalence of overweight and obesity in adolescents in
Bahia, Brazil. Nutr Hosp. 2013; 28 (2): 491–6. 29. Moreno LA, Gottrand F, Huybrechts I, Ruiz JR, González-
Gross M, DeHenauw S; HELENA Study Group. Nutrition
and Lifestyle in European Adolescents: the HELENA
(Healthy Liftestyle in Europe by Nutrition in Adolescence)
Study. Adv Nutr. 2014; 5 (5): 615S–23S. 21. Mendonça MRT, Silva MAM da, Rivera IR, Moura AA. Prevalência de sobrepeso e obesidade em crianças e adoles-
centes da cidade de Maceió. Rev Assoc Med Bras. 2010; 56
(2): 192–6. 30. Pereira FN, Oliveira JR de, Zöllner CC, Gambardella AMD. Percepção do peso corporal e fatores associados em estu-
dantes do Espírito Santo, Brasil. J Hum Growth Dev. 2013;
23 (3): 296–302. 22. Araújo MFM, Almeida LS de, Silva PCV da, Vasconcelos
HCA de, Lopes MV de O, Damasceno MMC. Sobrepeso
entre adolescentes de escolas particulares de Fortaleza, CE,
Brasil. Rev Bras Enferm. 2010; 63 (4): 651–8. 670
|
https://openalex.org/W4392646569
|
https://www.mdpi.com/2075-4426/14/3/293/pdf?version=1709967851
|
English
| null |
Cardiac Arrest and Complete Heart Block: Complications after Electrical Cardioversion for Unstable Supraventricular Tachycardia in the Emergency Department
|
Journal of personalized medicine
| 2,024
|
cc-by
| 7,613
|
Citation: Marza, A.M.; Barsac, C.;
Sutoi, D.; Cindrea, A.C.; Herlo, A.;
Trebuian, C.I.; Petrica, A. Cardiac
Arrest and Complete Heart Block:
Complications after Electrical
Cardioversion for Unstable
Supraventricular Tachycardia in the
Emergency Department. J. Pers. Med. 2024, 14, 293. https://doi.org/
10.3390/jpm14030293 Keywords: supraventricular tachycardia; cardioversion; unstable patient; complete heart block;
ineffective pacing; cardiac arrest; advanced life support Academic Editor: Gianluca Costa Adina Maria Marza 1,2
, Claudiu Barsac 1,3,*, Dumitru Sutoi 1
, Alexandru Cristian Cindrea 1,2
,
Alexandra Herlo 4, Cosmin Iosif Trebuian 1,5 and Alina Petrica 1,6 Adina Maria Marza 1,2
, Claudiu Barsac 1,3,*, Dumitru Sutoi 1
, Alexandru Cristian Cindrea 1,2
,
Alexandra Herlo 4, Cosmin Iosif Trebuian 1,5 and Alina Petrica 1,6 1
Department of Surgery, “Victor Babes” University of Medicine and Pharmacy, 300041 Timisoara, Romania;
marza.adina@umft.ro (A.M.M.); dumitru.sutoi@umft.ro (D.S.);
alexandru.cindrea.umfvbt@gmail.com (A.C.C.); trebuian.cosmin@umft.ro (C.I.T.); alina.petrica@umft.ro (A.P.) g
(
);
(
);
p
(
)
2
Emergency Department, Emergency Clinical Municipal Hospital, 300079 Timisoara, Romania
3
Clinic of Anaesthesia and Intensive Care, “Pius Brinzeu” Emergency Clinical County Hospital,
300736 Timisoara, Romania g
(
)
(
)
p
(
)
2
Emergency Department, Emergency Clinical Municipal Hospital, 300079 Timisoara, Romania Emergency Department, Emergency Clinical Municipal Hospital, 300079 Timisoara, Romania
3
Clinic of Anaesthesia and Intensive Care, “Pius Brinzeu” Emergency Clinical County Hospital,
300736 Timisoara, Romania 4
Department of Infectious Diseases, “Victor Babes” University of Medicine and Pharmacy, 300041 Timisoara,
Romania; alexandra.mocanu@umft.ro 5
Department of Anesthesia and Intensive Care, Emergency County Hospital, 320210 Resita, Romania
6
Emergency Department, “Pius Brinzeu” Emergency Clinical County Hospital, 300736 Timisoara, Romania
*
C
d
l
di
b
@
ft
T l
40 728950041 5
Department of Anesthesia and Intensive Care, Emergency County Hospital, 320210 Resita, Romania
6
E
D
“P
B
” E
Cl
l C
H
l
T
R p
,
g
y
y
p
,
,
6
Emergency Department, “Pius Brinzeu” Emergency Clinical County Hospital, 300736 Timisoara, Romania
*
Correspondence: claudiu.barsac@umft.ro; Tel.: +40-728950041 *
Correspondence: claudiu.barsac@umft.ro; Tel.: +40-728950041 Abstract: Synchronous electrical cardioversion is a relatively common procedure in the emergency
department (ED), often performed for unstable supraventricular tachycardia (SVT) or unstable
ventricular tachycardia (VT). However, it is also used for stable cases resistant to drug therapy, which
carries a risk of deterioration. In addition to the inherent risks linked with procedural sedation, there
is a possibility of malignant arrhythmias or bradycardia, which could potentially result in cardiac
arrest following this procedure. Here, we present a case of complete heart block unresponsive to
transcutaneous pacing and positive inotropic and chronotropic drugs for 90 min, resulting in multiple
cardiac arrests. The repositioning of the transcutaneous cardio-stimulation electrodes, one of them
placed in the left latero-sternal position and the other at the level of the apex, led to immediate
stabilization of the patient. The extubation of the patient was performed the following day, with full
recovery and discharge within 7 days after the insertion of a permanent pacemaker. Journal of
Personalized
Medicine Journal of
Personalized
Medicine 1. Introduction Patients with symptomatic supraventricular arrhythmias commonly present in the
emergency department (ED), necessitating urgent management. Sporadically, complica-
tions may arise, but there is a lack of comprehensive literature regarding post-cardioversion
events for supraventricular tachycardia (SVT). Received: 17 February 2024
Revised: 4 March 2024
Accepted: 6 March 2024
Published: 9 March 2024 p
y
Traditionally, SVT encompasses all tachycardias except for ventricular tachycardias
(VTs) and atrial fibrillation (AF), with atrial rates exceeding 100 beats per minute at rest [1]. Narrow QRS tachycardia is defined as a QRS duration of 120 ms or less, while sometimes,
they may display a widened QRS complex exceeding 120 ms due to pre-existing conduction
delays either related to heart rate or to bundle branch blocks [1–3]. Copyright: © 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article
distributed
under
the
terms
and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/). y
In the general population, the prevalence of SVT is 2.25 per 1000 individuals, with an
incidence of 35 per 100,000 person-years [1]; evidence from the United States indicates that
they contribute to approximately 50,000 ED visits each year [4]. However, epidemiological
studies on SVT populations are limited. Women face twice the risk of developing SVT
compared to men, while individuals aged 65 years or older have over five times the risk https://www.mdpi.com/journal/jpm J. Pers. Med. 2024, 14, 293. https://doi.org/10.3390/jpm14030293 J. Pers. Med. 2024, 14, 293 2 of 9 compared to their younger counterparts [1]. Additionally, SVT is also frequent in patients
with congenital heart disease [5]. g
The clinical presentations of SVT vary extensively, spanning from mild symptoms like
palpitations and breathing disturbances to severe symptoms associated with hemodynamic
instability and cardiogenic shock, which pose a risk to the patient’s life [6,7]. The assess-
ment and management of all arrhythmias consider both the patient’s condition and the
characteristics of the arrhythmia. The goal is to prevent cardiac arrest. Therefore, the initial approach in the ABCDE assessment involves identifying the
patient’s adverse features, such as shock, syncope, acute heart failure, and myocardial
ischemia. Additionally, it is essential to consistently monitor the heart rhythm and blood
pressure and administer oxygen if SpO2 falls below 94%. Identifying and addressing
reversible causes, such as electrolyte imbalances or hypovolemia, should be conducted
in accordance with the 2021 European Resuscitation Council (ERC) Guidelines [8]. If
these signs are absent in a patient with regular tachycardia, vagal maneuvers will be
performed [9], with the inverted Valsalva maneuver demonstrated to be more efficient
in adults [1]. In the ED, the standard protocol includes conducting a thorough history,
physical examination, and a 12-lead ECG, supplemented by usual laboratory tests such
as full blood counts, biochemistry profile, and thyroid function assessment. If feasible,
transthoracic echocardiography should also be conducted. g
p y
If vagal maneuvers fail to resolve the issue, the initial drug of choice is adenosine
(6–12–18 mg) [1,8]. A recently published study by Xiao et al. compared the efficiency of Val-
salva maneuvers, adenosine, and their combination, but the results were inconclusive [10]. If adenosine proves ineffective, intravenous verapamil, diltiazem, or beta-blockers are the
subsequent treatment options for narrow complex SVT, while intravenous procainamide
or amiodarone are recommended for wide complex SVT. Given that atrioventricular node
blockers are contraindicated for patients with pre-excited atrial fibrillation [11], the differ-
ential diagnosis should be meticulously performed before their administration. If these
treatments are ineffective, synchronized cardioversion of up to three attempts is advised
to terminate the tachycardia. Having a stable patient provides the advantage of granting
the emergency physician the opportunity to seek expert advice for both the differential
diagnosis of SVT and its treatment if initial measures prove unsuccessful. For unstable patients exhibiting life-threatening features, synchronized cardioversion
under sedation is the treatment of choice [12]. If unsuccessful, administering intravenous
amiodarone at a dose of 300 mg over 10–20 min or intravenous procainamide at a dose of
10–15 mg/kg over 20 min is recommended, followed by repeating synchronized shocks, if
necessary [1,8]. Here, we describe a case of a patient requiring electrical cardioversion for SVT. Fol-
lowing the synchronized shock, the patient experienced severe bradycardia, subsequently
progressing to complete heart block unresponsive to medication and pacing, culminating
in cardiorespiratory arrest. 2. Case Presentation A 53-year-old male patient, a known smoker with no other comorbidities except for
a right bundle branch block (RBBB), arrived at the ED via a physician-staffed ambulance. The patient presented with main complaints of palpitations and fatigue that started approx-
imately 8 h before arrival, along with diaphoresis and dyspnea exacerbated by minimal
efforts, particularly in the last hour. Before reaching the hospital, a 12-lead ECG (Figure 1) and vital signs monitoring
were conducted, revealing SVT with RBBB, a heart rate of 174 BPM, SpO2 at 98%, and
blood pressure of 130/80 mmHg. Deeming the patient’s condition stable, the emergency
physician attempted vagal maneuvers, which had no effect on the heart rate. Adenosine
was administered in three doses (6 mg, 12 mg, 18 mg), also with no impact on the pa-
tient’s condition. After a 30 min period during which 10 mg of metoprolol was slowly J. Pers. Med. 2024, 14, 293
J. Pers. Med. 2024, 14, x FOR 3 of 9
of 10 3 of 9
of 10 intravenously administered without success, the decision was made to transfer the patient
to the ED. intravenously administered without success, the decision was made to transfer the patient
to the ED. intravenously administered without success, the decision was made to transfer the patient
to the ED. ntravenously administered without success, the decision was made to transfer the patient
to the ED. intravenously administered without success, the decision was made to transfer the patient
to the ED. to the ED. Figure 1. A 12 lead-ECG from the ambulance: regular rhythm tachycardia (heart rate 174 BPM) and
wide QRS complexes of 0.14 s, with rSR pattern in V1 and V2; findings indicative of supraventric-
ular tachycardia (SVT) with right bundle branch block (RBBB). Figure 1. A 12 lead-ECG from the ambulance: regular rhythm tachycardia (heart rate 174 BPM) and
wide QRS complexes of 0.14 s, with rSR’ pattern in V1 and V2; findings indicative of supraventricular
tachycardia (SVT) with right bundle branch block (RBBB). ,
p
he ambulance: regular rhythm tachycardia (heart rate 174 BPM) and
with rSR pattern in V1 and V2; findings indicative of supraventric-
ht bundle branch block (RBBB). the patient appeared conscious and cooperative but he was
he ambulance: regular rhythm tachycardia (heart rate 174 BPM) and
with rSR’ pattern in V1 and V2; findings indicative of supraventricular
undle branch block (RBBB). 2. Case Presentation First 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) from ED—regular
rhythm tachycardia (heart rate 174 BPM), QRS duration of 0.14 s, rSR’ pattern in V1 and V2 (arrows),
absent P waves, negative T waves in V1 and V2; findings suggestive for SVT with RBBB. Figure 2. First 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) from ED—regular
rhythm tachycardia (heart rate 174 BPM), QRS duration of 0.14 s, rSR pattern in V1 and V2 (arrows),
absent P waves, negative T waves in V1 and V2; findings suggestive for SVT with RBBB. Figure 2. First 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) from ED—regular
rhythm tachycardia (heart rate 174 BPM), QRS duration of 0.14 s, rSR’ pattern in V1 and V2 (arrows),
absent P waves, negative T waves in V1 and V2; findings suggestive for SVT with RBBB. Figure 2. First 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) from ED—regular
rhythm tachycardia (heart rate 174 BPM), QRS duration of 0.14 s, rSR pattern in V1 and V2 (arrows),
absent P waves, negative T waves in V1 and V2; findings suggestive for SVT with RBBB. Figure 2. First 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) from ED—regular
rhythm tachycardia (heart rate 174 BPM), QRS duration of 0.14 s, rSR’ pattern in V1 and V2 (arrows),
absent P waves, negative T waves in V1 and V2; findings suggestive for SVT with RBBB. The patient was administered supplemental oxygen at a rate of 3 L/min; b
up and arterial blood gas analysis were conducted (Table 1) After approximat
Table 1. Pathological values of the laboratory tests performed upon arrival in the ED. up and arterial blood gas analysis were conducted (Table 1). After approximately 30 min,
it was decided that synchronous cardioversion with 70 joules was the optimal course of
action. The patient provided consent for the procedure and was sedated beforehand. Table 1. Pathological values of the laboratory tests performed upon arrival in the ED. 2. Case Presentation , the patient appeared conscious and cooperative, but he was Figure 1. A 12 lead-ECG from t
Figure 1. A 12 lead-ECG from t
id QRS
l
f 0 14 Figure 1. A 12 lead-ECG from the ambulance: regular rhythm tachycardia (heart rate 174 BPM) and
wide QRS complexes of 0.14 s, with rSR pattern in V1 and V2; findings indicative of supraventric-
ular tachycardia (SVT) with right bundle branch block (RBBB). Figure 1. A 12 lead-ECG from the ambulance: regular rhythm tachycardia (heart rate 174 BPM) and
wide QRS complexes of 0.14 s, with rSR’ pattern in V1 and V2; findings indicative of supraventricular
tachycardia (SVT) with right bundle branch block (RBBB). Upon arrival at the ED, the patient appeared conscious and cooperative, but he was
pale, diaphoretic, and exhibited dyspnea at rest. Vital signs indicated a peripheral oxygen
saturation of 93%, blood pressure at 90/60 mmHg, a heart rate of 174 BPM, a capillary refill
time of 3 s, and a barely detectable radial pulse. The ECG showed SVT with RBBB, as seen
in Figure 2
Upon arrival at the ED, the patient appeared conscious and cooperative, but he was
pale, diaphoretic, and exhibited dyspnea at rest. Vital signs indicated a peripheral oxygen
saturation of 93%, blood pressure at 90/60 mmHg, a heart rate of 174 BPM, a capillary refill
time of 3 s, and a barely detectable radial pulse. The ECG showed SVT with RBBB, as seen
in Figure 2. in Figure 2. The patient was administered supplemental oxygen at a rate of 3 L/min; blood work-
up and arterial blood gas analysis were conducted (Table 1). After approximately 30 min,
it was decided that synchronous cardioversion with 70 joules was the optimal course of
action. The patient provided consent for the procedure and was sedated beforehand. J. Pers. Med. 2024, 14, 293
J. Pers. Med. 2024, 14, x FO 4 of 9
of 10 Figure 2. First 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) from ED—regular
rhythm tachycardia (heart rate 174 BPM), QRS duration of 0.14 s, rSR pattern in V1 and V2 (arrows),
absent P waves, negative T waves in V1 and V2; findings suggestive for SVT with RBBB. Figure 2. 2. Case Presentation A 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) after ROSC shows atrio-
ventricular dissociation, with a ventricular heart rate of 27 BPM and QRS duration of 0.17 s, regular
P waves (arrows), variable PR interval, right axis deviation, negative T waves in DII, DIII, aVF, V4–
V6 and ST depression in the V3–V5 leads. The findings are consistent with a complete heart block
and myocardial ischemia in the infero-lateral territory. Figure 4. A 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) after ROSC shows
atrio-ventricular dissociation, with a ventricular heart rate of 27 BPM and QRS duration of 0.17 s,
regular P waves (arrows), variable PR interval, right axis deviation, negative T waves in DII, DIII,
aVF, V4–V6 and ST depression in the V3–V5 leads. The findings are consistent with a complete heart
block and myocardial ischemia in the infero-lateral territory. Figure 4. A 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) after ROSC shows atrio-
ventricular dissociation, with a ventricular heart rate of 27 BPM and QRS duration of 0.17 s, regular
P waves (arrows), variable PR interval, right axis deviation, negative T waves in DII, DIII, aVF, V4–
V6 and ST depression in the V3–V5 leads. The findings are consistent with a complete heart block
and myocardial ischemia in the infero-lateral territory. Figure 4. A 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) after ROSC shows
atrio-ventricular dissociation, with a ventricular heart rate of 27 BPM and QRS duration of 0.17 s,
regular P waves (arrows), variable PR interval, right axis deviation, negative T waves in DII, DIII,
aVF, V4–V6 and ST depression in the V3–V5 leads. The findings are consistent with a complete heart
block and myocardial ischemia in the infero-lateral territory. Despite efforts to improve hemodynamic stability, the transcutaneous pacing re
mained ineffective (Figure 5). The patient s thorax was shaved to enhance transcutaneous
conduction, and the initial electrode position (right subclavian/cardiac apex) was changed
to an antero-posterior and, later, to a latero-lateral position. The Adrenaline dose was in-
creased from 2 mcg/min to 20 mcg/min. Additionally, alternative medications, including
Despite efforts to improve hemodynamic stability, the transcutaneous pacing remained
ineffective (Figure 5). 2. Case Presentation Laboratory Test
Value
Reference Range Value
Conventional Units
Blood glucose
146
74–106
mg/dL
Creatinine
1.52
0.70–1.30
mg/dL
D-dimer
1.89
<0.68
mg/L
g
y
p
p
Laboratory Test
Value
Reference Range Value
Conventional Units
Blood glucose
146
74–106
mg/dL
Creatinine
1.52
0.70–1.30
mg/dL
D-dimer
1.89
<0.68
mg/L
Lactate
2.52
0.36–0.75
mmol/L
NT-pro-BNP
10,217
<125
pg/mL
Troponin I
58.2
17–50
ng/L
White blood cells
11.1
4.0–10.0
×109/µL
Abbreviations: NT-pro-BNP, N-terminal pro-B-type natriuretic peptide. p
g
y
(
)
pp
y
,
it was decided that synchronous cardioversion with 70 joules was the optimal course of
Laboratory Test
Value
Reference Range Value
Conventional Units Lactate
2.52
0.36–0.75
mmol/L
NT-pro-BNP
10,217
<125
pg/mL
Troponin I
58.2
17–50
ng/L
White blood cells
11.1
4.0–10.0
×109/µL
Abbreviations: NT-pro-BNP, N-terminal pro-B-type natriuretic peptide. Following the initial synchronous shock, the patient experienced severe bradycardia
(Figure 3) for a few seconds, transitioning into asystole. Immediate resuscitation measures,
including chest compressions and bag-mask ventilation, were initiated. After about 30 s,
the patient exhibited spontaneous breathing and movement of limbs, opened his eyes, and
responded to verbal stimuli. REVIEW
5 of 10 Following the initial synchronous shock, the patient experienced severe bradycardia
(Figure 3) for a few seconds, transitioning into asystole. Immediate resuscitation measures,
including chest compressions and bag-mask ventilation, were initiated. After about 30 s,
the patient exhibited spontaneous breathing and movement of limbs, opened his eyes, and
responded to verbal stimuli. Figure 3. The defibrillator s rhythm recording during the electrical cardioversion shows irregular
bradycardia after the synchronous shock for SVT. Figure 3. The defibrillator’s rhythm recording during the electrical cardioversion shows irregular
bradycardia after the synchronous shock for SVT. Figure 3. The defibrillator s rhythm recording during the electrical cardioversion shows irregular
bradycardia after the synchronous shock for SVT. Figure 3. The defibrillator’s rhythm recording during the electrical cardioversion shows irregular
bradycardia after the synchronous shock for SVT. J. Pers. Med. 2024, 14, 293 5 of 9
ular A repeated ECG recording revealed a third-degree AV block (Figure 4), with a heart
rate of 23 BPM, and the patient was hemodynamically unstable. Intravenous Atropine
0.5 mg was administered, followed by additional doses every 2 min, up to a maximum
of 3 mg. Simultaneously, Adrenaline was administered via a syringe infusion pump with
2 mcg/min, with no improvement in the patient’s condition. Transcutaneous pacing
was initiated with a frequency set to “Demand” at 70 BPM, 80 mA intensity. 2. Case Presentation Although
the monitor indicated efficient capture, the femoral pulse was not concordant. Pacing
parameters were adjusted to 70 BPM with an increase in intensity up to 160 mA and
even 200 mA for short periods of time, yet the myocardium remained unresponsive to
external pacing. A repeated ECG recording revealed a third-degree AV block (Figure 4), with a heart
rate of 23 BPM, and the patient was hemodynamically unstable. Intravenous Atropine 0.5
mg was administered, followed by additional doses every 2 min, up to a maximum of 3
mg. Simultaneously, Adrenaline was administered via a syringe infusion pump with 2
mcg/min, with no improvement in the patient s condition. Transcutaneous pacing was
initiated with a frequency set to “Demand” at 70 BPM, 80 mA intensity. Although the
monitor indicated efficient capture, the femoral pulse was not concordant. Pacing param-
eters were adjusted to 70 BPM with an increase in intensity up to 160 mA and even 200
mA for short periods of time, yet the myocardium remained unresponsive to external pac-
ing. Figure 4. A 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) after ROSC shows atrio-
ventricular dissociation, with a ventricular heart rate of 27 BPM and QRS duration of 0.17 s, regular
P waves (arrows), variable PR interval, right axis deviation, negative T waves in DII, DIII, aVF, V4–
V6 and ST depression in the V3–V5 leads. The findings are consistent with a complete heart block
and myocardial ischemia in the infero-lateral territory. De
ite effo t
to i
o e he
ody a
i
tability the t a
uta eou
a i
e
Figure 4. A 12-lead ECG (recorded at 25 mm/s, and a voltage of 10 mm/mV) after ROSC shows
atrio-ventricular dissociation, with a ventricular heart rate of 27 BPM and QRS duration of 0.17 s,
regular P waves (arrows), variable PR interval, right axis deviation, negative T waves in DII, DIII,
aVF, V4–V6 and ST depression in the V3–V5 leads. The findings are consistent with a complete heart
block and myocardial ischemia in the infero-lateral territory. Figure 4. 2. Case Presentation Despite
exhausting all available treatment options in the ED (which lacked equipment for trans-
venous pacing), the patient continued to experience severe hypotension between cardio-
pulmonary arrest episodes due to the unresponsiveness to transthoracic cardio-stimula-
tion. Considering the inefficacy of pacing, attributable to the patient s thoracic anatomy
with a large anterior-to-posterior diameter, a decision was made to reposition the trans-
thoracic pacing leads to subclavicular left (latero-sternal) and cardiac apex (replacing ECG
lead V6) positions (Figure 6). Upon reassessment, the change in lead position resulted in
successful pacing capture, confirmed by femoral artery pulse and an increase in blood
pressure values. Figure 6. Placement of both transcutaneous stimulation electrodes on the left hemithorax:
subclavicular left (latero-sternal) and cardiac apex (replacing ECG lead V6) positions. Figure 6. Placement of both transcutaneous stimulation electrodes on the left hemithorax: subclavicu-
lar left (latero-sternal) and cardiac apex (replacing ECG lead V6) positions. lead V6) positions (Figure 6). Upon reassessment, the change in lead position resulted in
successful pacing capture, confirmed by femoral artery pulse and an increase in blood
pressure values. Figure 6. Placement of both transcutaneous stimulation electrodes on the left hemithorax:
subclavicular left (latero-sternal) and cardiac apex (replacing ECG lead V6) positions. Figure 6. Placement of both transcutaneous stimulation electrodes on the left hemithorax: subclavicu-
lar left (latero-sternal) and cardiac apex (replacing ECG lead V6) positions. Approximately 90 min after the initial cardioversion attempt, the patient s stability
allowed for transportation to the regional Institute for Cardiovascular Diseases for
transvenous pacing. The final evaluation indicated a blood pressure of 115/50 mmHg,
heart rate of 70 BPM, consistent femoral pulse, GCS of 3 with the patient mechanically
ventilated under continuous sedative medication and receiving inotropic and vasopressor
medication (Adrenaline and Dopamine). Emergency transthoracic echocardiography
showed a left ventricle of normal size with preserved systolic function, an ejection fraction
of 50%, medio-basal hypokinesia of the lateral wall, concentric left ventricular
hypertrophy, grade II mitral and tricuspid regurgitation, medium secondary pulmonary
Approximately 90 min after the initial cardioversion attempt, the patient’s stability
allowed for transportation to the regional Institute for Cardiovascular Diseases for transve-
nous pacing. The final evaluation indicated a blood pressure of 115/50 mmHg, heart rate
of 70 BPM, consistent femoral pulse, GCS of 3 with the patient mechanically ventilated
under continuous sedative medication and receiving inotropic and vasopressor medica-
tion (Adrenaline and Dopamine). 2. Case Presentation Considering the inefficacy of pacing, attributable to the patient s thoracic anatomy
with a large anterior-to-posterior diameter, a decision was made to reposition the trans-
thoracic pacing leads to subclavicular left (latero-sternal) and cardiac apex (replacing ECG
lead V6) positions (Figure 6). Upon reassessment, the change in lead position resulted in
successful pacing capture, confirmed by femoral artery pulse and an increase in blood
pressure values. Figure 5. Transcutaneous pacing with ineffective capture and inconsistent femoral pulse. Pacing
settings: mode—demand, frequency—70 BPM, intensity—160 mA. Figure 5. Transcutaneous pacing with ineffective capture and inconsistent femoral pulse. Pacing
settings: mode—demand, frequency—70 BPM, intensity—160 mA. pulmonary arrest episodes due to the unresponsiveness to transthoracic cardio-stimula-
tion. Considering the inefficacy of pacing, attributable to the patient s thoracic anatomy
with a large anterior-to-posterior diameter, a decision was made to reposition the trans-
thoracic pacing leads to subclavicular left (latero-sternal) and cardiac apex (replacing ECG
lead V6) positions (Figure 6). Upon reassessment, the change in lead position resulted in
successful pacing capture, confirmed by femoral artery pulse and an increase in blood
pressure values. Figure 5. Transcutaneous pacing with ineffective capture and inconsistent femoral pulse. Pacing
settings: mode—demand, frequency—70 BPM, intensity—160 mA. Figure 5. Transcutaneous pacing with ineffective capture and inconsistent femoral pulse. Pacing
settings: mode—demand, frequency—70 BPM, intensity—160 mA. successful pacing capture, confirmed by femoral artery pulse and an increase in blood
pressure values. Throughout the patient s stay i
least 10 times, manifesting as either
patient responded positively to exte
and Adrenaline administration, achi
2 min. The on-call physician at the reg
tacted and agreed to admit the patien
exhausting all available treatment o
venous pacing), the patient continue
pulmonary arrest episodes due to th
tion. Considering the inefficacy of p
with a large anterior-to-posterior di
thoracic pacing leads to subclavicula
lead V6) positions (Figure 6) Upon Throughout the patient s stay in the ED, he experienced cardiopulmonary arrest at
least 10 times, manifesting as either asystole or pulseless electrical activity. Each time, the
patient responded positively to external thoracic compressions, mechanical ventilation,
and Adrenaline administration, achieving a return of spontaneous circulation in less than
2 min. The on-call physician at the regional Institute for Cardiovascular Diseases was con-
tacted and agreed to admit the patient once his condition was stable for transport. 2. Case Presentation Emergency transthoracic echocardiography showed a
left ventricle of normal size with preserved systolic function, an ejection fraction of 50%,
medio-basal hypokinesia of the lateral wall, concentric left ventricular hypertrophy, grade
II mitral and tricuspid regurgitation, medium secondary pulmonary hypertension, dilated
right ventricle, and a posterior pericardial fluid blade measuring below 1 cm. Figure 6. Placement of both transcutaneous stimulation electrodes on the left hemithorax:
Upon arrival at the regional Institute for Cardiovascular Diseases, the patient’s con-
dition improved with the placement of the transvenous pacing probe, later replaced with
a permanent pacemaker implant. The following day, the patient was extubated, demon-
strating complete hemodynamic and neurologic recovery, and was discharged from the
hospital a week later. 2. Case Presentation The patient’s thorax was shaved to enhance transcutaneous conduc-
tion, and the initial electrode position (right subclavian/cardiac apex) was changed to an
antero-posterior and, later, to a latero-lateral position. The Adrenaline dose was increased
from 2 mcg/min to 20 mcg/min. Additionally, alternative medications, including Amino-
phylline 24 mg over 10 min and Dopamine via a syringe infusion pump at 10 mcg/kg/min,
were administered. Throughout the patient’s stay in the ED, he experienced cardiopulmonary arrest at
least 10 times, manifesting as either asystole or pulseless electrical activity. Each time, the
patient responded positively to external thoracic compressions, mechanical ventilation, and
Adrenaline administration, achieving a return of spontaneous circulation in less than 2 min. g
p
The on-call physician at the regional Institute for Cardiovascular Diseases was con-
tacted and agreed to admit the patient once his condition was stable for transport. Despite
exhausting all available treatment options in the ED (which lacked equipment for transve- J. Pers. Med. 2024, 14, 293 6 of 9 nous pacing), the patient continued to experience severe hypotension between cardiopul-
monary arrest episodes due to the unresponsiveness to transthoracic cardio-stimulation. Considering the inefficacy of pacing, attributable to the patient’s thoracic anatomy with a
large anterior-to-posterior diameter, a decision was made to reposition the transthoracic
pacing leads to subclavicular left (latero-sternal) and cardiac apex (replacing ECG lead V6)
positions (Figure 6). Upon reassessment, the change in lead position resulted in successful
pacing capture, confirmed by femoral artery pulse and an increase in blood pressure values. REVIEW
6 of 10
Aminophylline 24 mg over 10 min and Dopamine via a syringe infusion pump at 10
mcg/kg/min, were administered. least 10 times, manifesting as either asystole or pulseless electrical activity. Each time, the
patient responded positively to external thoracic compressions, mechanical ventilation,
and Adrenaline administration, achieving a return of spontaneous circulation in less than
2 min. The on-call physician at the regional Institute for Cardiovascular Diseases was con-
tacted and agreed to admit the patient once his condition was stable for transport. Despite
exhausting all available treatment options in the ED (which lacked equipment for trans-
venous pacing) the patient continued to experience severe hypotension between cardio g
g
Figure 5. Transcutaneous pacing with ineffective capture and inconsistent femoral pulse. Pacing
settings: mode—demand, frequency—70 BPM, intensity—160 mA. 2. Case Presentation Throughout the patient s stay in the ED, he experienced cardiopulmonary arrest at
least 10 times, manifesting as either asystole or pulseless electrical activity. Each time, the
patient responded positively to external thoracic compressions, mechanical ventilation,
and Adrenaline administration, achieving a return of spontaneous circulation in less than
2 min. The on-call physician at the regional Institute for Cardiovascular Diseases was con-
tacted and agreed to admit the patient once his condition was stable for transport. Despite
exhausting all available treatment options in the ED (which lacked equipment for trans-
venous pacing), the patient continued to experience severe hypotension between cardio-
pulmonary arrest episodes due to the unresponsiveness to transthoracic cardio-stimula-
tion. Considering the inefficacy of pacing, attributable to the patient s thoracic anatomy
with a large anterior-to-posterior diameter, a decision was made to reposition the trans-
thoracic pacing leads to subclavicular left (latero-sternal) and cardiac apex (replacing ECG
lead V6) positions (Figure 6). Upon reassessment, the change in lead position resulted in
successful pacing capture, confirmed by femoral artery pulse and an increase in blood
pressure values. Figure 5. Transcutaneous pacing with ineffective capture and inconsistent femoral pulse. Pacing
settings: mode—demand, frequency—70 BPM, intensity—160 mA. venous pacing), the patient continued to experience severe hypotension between cardio-
pulmonary arrest episodes due to the unresponsiveness to transthoracic cardio-stimula-
tion. Considering the inefficacy of pacing, attributable to the patient s thoracic anatomy
with a large anterior-to-posterior diameter, a decision was made to reposition the trans-
thoracic pacing leads to subclavicular left (latero-sternal) and cardiac apex (replacing ECG
lead V6) positions (Figure 6). Upon reassessment, the change in lead position resulted in
successful pacing capture, confirmed by femoral artery pulse and an increase in blood
pressure values. Figure 6. Placement of both transcutaneous stimulation electrodes on the left hemithorax:
subclavicular left (latero-sternal) and cardiac apex (replacing ECG lead V6) positions. Figure 6. Placement of both transcutaneous stimulation electrodes on the left hemithorax: subclavicu-
lar left (latero-sternal) and cardiac apex (replacing ECG lead V6) positions. Figure 5. Transcutaneous pacing with ineffective capture and inconsistent femoral pulse. Pacing
settings: mode—demand, frequency—70 BPM, intensity—160 mA. Figure 5. Transcutaneous pacing with ineffective capture and inconsistent femoral pulse. Pacing
settings: mode—demand, frequency—70 BPM, intensity—160 mA. pulmonary arrest episodes due to the unresponsiveness to transthoracic cardio-stimula-
tion. subclavicular lef
3. Discussion Chronologically, the decision to proceed with electrical cardioversion was made over
an hour after the last bolus of metoprolol, during which time no significant reduction in
heart rate was observed. Severe bradycardia, immediately followed by complete heart block and subsequent
cardiac arrest with pulseless electrical activity, was an unexpected and rarely reported
complication of synchronized cardioversion. Similar outcomes were described by Gallagher
et al., who conducted a retrospective cohort study examining the relationship between
shock energy and arrhythmic complications of electrical cardioversion. Sinus bradycardia
or a slow junctional escape rhythm was observed in 22 cases, with 20 resolving within
minutes after cardioversion. While two patients required permanent pacing before hospital
discharge, neither needed rate support while awaiting pacemaker implantation. None of
these patients experienced cardiac arrest. They also found that the incidence of ventricular
fibrillation (VF) following shocks of <200 J was significantly higher compared to higher
energy shocks (5 out of 2959 vs. 0 out of 3439 shocks, p = 0.021). Additionally, non-
sustained broad complex tachycardia occurred in four cases, all lasting less than 10 s: two
after shocks > 200 J and two after shocks less than 200 J. The induction of atrial fibrillation
(AF) was significantly more common with shocks of <200 J (20 out of 930 shocks vs. 1 out
of 313 shocks at ≥200 J, p = 0.015) [17]. The success of cardioversion relies on several factors, with time being the most crucial. In this case, the patient experienced symptoms for several hours, and the initial EKG
recording, which revealed SVT with a heart rate of 174, was conducted more than three
hours prior to arriving at the ED. Nevertheless, the patient initially declined to come to the
hospital. The prolonged duration of the tachyarrhythmia could potentially lead to both
post-repolarization and conduction delays due to global ischemia, as described in other
studies, which reported VF as a complication following cardioversion for AF [18,19]. Furthermore, a proposed theory regarding the mechanism of complete heart block
in this patient was the administration of intravenous metoprolol before cardioversion,
given that beta blockers are known as drugs with sinoatrial and/or atrioventricular nodal-
blocking properties [20]. In a retrospective and prospective study conducted by Osmonov
et al. subclavicular lef
3. Discussion Approximately 90 min after the initial cardioversion attempt, the patient s stability
allowed for transportation to the regional Institute for Cardiovascular Diseases for
transvenous pacing. The final evaluation indicated a blood pressure of 115/50 mmHg,
heart rate of 70 BPM, consistent femoral pulse, GCS of 3 with the patient mechanically
ventilated under continuous sedative medication and receiving inotropic and vasopressor
Synchronized cardioversion, a potentially life-saving procedure, is commonly utilized
in the emergency department for hemodynamically unstable tachyarrhythmias. Emergency
physicians should possess a thorough understanding of the indications and potential
complications before recommending or performing this intervention. The effectiveness of
frequently utilized anti-arrhythmic drugs is restricted in these situations, primarily due to J. Pers. Med. 2024, 14, 293 7 of 9 concerns over side effects and their potential to induce arrhythmias, thereby limiting their
usage [13]. concerns over side effects and their potential to induce arrhythmias, thereby limiting their
usage [13]. When selecting the appropriate method for cardioversion, it is important to follow
the current guidelines and carefully weigh the potential benefits and risks associated with
each intervention. Sometimes, the patient is at the threshold of receiving either electrical or
drug cardioversion and requires a prompt decision to distinguish between the two, given
that both interventions carry inherent risks. Ventricular fibrillation (VF) as a complication
of electrical cardioversion was documented in numerous studies, particularly when car-
dioversion takes place during the vulnerable period of repolarization, typically around the
peak of the T wave on the ECG [14,15]. In 2004, Lyndon and Abdul described such a case,
highlighting the significance of adjusting the lead configuration on the defibrillator monitor
to prevent mistaking the high T wave for the R wave, thereby averting the induction
of VF during the administration of synchronous external electric shock [15]. Kaufmann
et al. described two cases of iatrogenic ventricular fibrillation after the cardioversion of
pre-excited atrial fibrillation due to inadvertent T-wave synchronization [16]. In this scenario, the patient was presented with recent-onset palpitations lasting several
hours, and appropriate drug therapy had already been administered in prehospital settings. Given the unavailability of intravenous verapamil or diltiazem in the region, the only
remaining option for terminating the tachycardia was electrical cardioversion. Considering
the patient’s known history of right bundle branch block, the tachycardia was managed as
SVT. subclavicular lef
3. Discussion involving 108 patients treated with atrioventricular blockers and presenting symp-
tomatic type II second- or third-degree AV block, 2:1 AV block, atrial fibrillation, and brad-
yarrhythmia, it was found that 36 patients treated with metoprolol experienced metoprolol-
induced AV blocks that persisted or recurred in 24 patients [21]. J. Pers. Med. 2024, 14, 293 8 of 9 However, the maximum therapeutic dose of 15 mg (recommended by ESC guidelines,
American College of Cardiology/American Heart Association Task Force on Clinical Prac-
tice Guidelines, and the Heart Rhythm Society for stable SVT) [1,20] was not achieved in
this case; only 10 mg was administered intravenously in 2.5 mg boluses, with no discernible
effect on heart rate following the last bolus. This hypothesis was considered due to the
lack of effectiveness of the transcutaneous pacing, assuming the patient had a stronger
response to beta-blockers. Unfortunately, glucagon, the antidote for beta-blocker overdose,
was unavailable at the time in any of the hospitals in the area, preventing the assessment of
this hypothesis. yp
Also, myocardial ischemia or metabolic disturbances such as acidosis and hypoxia
were described as factors that can elevate the pacing threshold and potentially prevent
capture [22]. The patient experienced both metabolic acidosis and severe hypoxemia in
the period following cardioversion, conditions that were rectified only after successful
cardiac pacing. Successful capture is typically identified by a widened QRS complex, succeeded by
a clear ST segment and broad T wave. A pulse rate manually confirmed in the femoral
artery or right carotid artery notably lower than the pacing rate displayed on the pacing
unit monitor may suggest a lack of capture [22]. In this case, achieving efficient capture required placing the electrodes closer together. While we cannot definitively assert that this positional change was the sole factor stabilizing
the patient, given the limited application to only one patient, it proved to be the sole
measure in a unique and critical situation that yielded an immediate positive effect, leading
to a sudden improvement in the patient’s condition. Consequently, we cannot consistently
advocate or recommend this procedure in routine practice. However, in similar situations
where other well-known methods prove ineffective and the patient’s condition continuously
deteriorates, as exemplified in this case report, it may be considered a life-saving measure. 4. Conclusions Cardiac arrest and complete heart block are uncommon complications following
electrical cardioversion. Given the infrequency of capture failure cases with transcutaneous
pacing, addressing each isolated case can provide significant benefits to both the ED and
prehospital staff, particularly in the management of atypical situations. Author Contributions: Conceptualization, A.M.M.; methodology, A.M.M. and C.B.; software, A.C.C.;
validation, C.B., C.I.T. and A.P.; investigation, A.M.M., A.H. and C.I.T.; resources, A.M.M.; data
curation, A.M.M.; writing—original draft preparation, A.M.M. and A.P.; writing—review and editing,
A.M.M., D.S., C.B., A.C.C., A.H. and A.P.; visualization, D.S. and A.C.C.; supervision, A.P. All authors
have read and agreed to the published version of the manuscript. Funding: The APC was funded by “Victor Babes” University of Medicine and Pharmacy from Timisoara Institutional Review Board Statement: The study was conducted in accordance with the Declaration
of Helsinki and approved by the Ethics Committee of Emergency Clinical Municipal Hospital from
Timisoara, Romania (number 10050/12.04.2023). Institutional Review Board Statement: The study was conducted in accordance with the Declaration
of Helsinki and approved by the Ethics Committee of Emergency Clinical Municipal Hospital from
Timisoara, Romania (number 10050/12.04.2023). Informed Consent Statement: Written informed consent has been obtained from the patient to
publish this paper. Informed Consent Statement: Written informed consent has been obtained from the patient to
publish this paper. Informed Consent Statement: Written informed consent has been obtained from the patient to
publish this paper. Data Availability Statement: The data presented in this study are available upon request from the
corresponding author. Data Availability Statement: The data presented in this study are available upon request from the
corresponding author. Conflicts of Interest: The authors declare no conflicts of interest. Conflicts of Interest: The authors declare no conflicts of interest. J. Pers. Med. 2024, 14, 293 9 of 9 References 1. Brugada, J.; Katritsis, D.G.; Arbelo, E.; Arribas, F.; Bax, J.J.; Blomström-Lundqvist, C.; Calkins, H.; Corrado, D.; Deftereos, S.G.;
Diller, G.-P.; et al. 2019 ESC Guidelines for the Management of Patients with Supraventricular TachycardiaThe Task Force for the
Management of Patients with Supraventricular Tachycardia of the European Society of Cardiology (ESC). Eur. Heart J. 2020, 41,
655–720. [CrossRef] [PubMed] 1. Brugada, J.; Katritsis, D.G.; Arbelo, E.; Arribas, F.; Bax, J.J.; Blomström-Lundqvist, C.; Calkins, H.; Corrado, D.; Deftereos, S.G.;
Diller, G.-P.; et al. 2019 ESC Guidelines for the Management of Patients with Supraventricular TachycardiaThe Task Force for the
Management of Patients with Supraventricular Tachycardia of the European Society of Cardiology (ESC). Eur. Heart J. 2020, 41,
655–720. [CrossRef] [PubMed] 2. Bibas, L.; Levi, M.; Essebag, V. Diagnosis and Management of Supraventricular Tachycardias. Can. Med Assoc. J. 2016, 188,
E466–E473. [CrossRef] [PubMed] 2. Bibas, L.; Levi, M.; Essebag, V. Diagnosis and Management of Supraventricular Tachycardias. Can. Med Assoc. J. 2016, 188,
E466–E473. [CrossRef] [PubMed] 3. Ding, W.Y.; Mahida, S. Wide Complex Tachycardia: Differentiating Ventricular Tachycardia from Supraventricular Tachycardia. Heart 2021, 107, 1995–2003. [CrossRef] [PubMed] 3. Ding, W.Y.; Mahida, S. Wide Complex Tachycardia: Differentiating Ventricular Tachycardia from Supraventricular Tachycardia. Heart 2021, 107, 1995–2003. [CrossRef] [PubMed] 4. Murman, D.H.; McDonald, A.J.; Pelletier, A.J.; Camargo, C.A. U.S. Emergency Department Visits for Supraventricular Tachycardia,
1993–2003. Acad. Emerg. Med. 2007, 14, 578–581. [CrossRef] [PubMed] 5. Wasmer, K.; Eckardt, L. Management of Supraventricular Arrhythmias in Adults with Congenital Heart Disease. Heart 2016, 102,
1614–1619. [CrossRef] [PubMed] V. Supraventricular Tachycardia; StatPearls Publishing: Treasure Island, FL, USA, 2024. 6. Patti, L.; Ashurst, J.V. Supraventricular Tachycardia; StatPearls Publishing: Treasure Island, FL, USA, 202 7. Shah, R.L.; Badhwar, N. Approach to Narrow Complex Tachycardia: Non-Invasive Guide to Interpretation and Management. Heart 2020, 106, 772–783. [CrossRef] [PubMed] 8. Current ERC Guidelines. Available online: https://cprguidelines.eu/ (accessed on 31 January 2024). 9
P
b k
S Sl
R M
h
t F S
t i
l
T
h
di
I
H
db
k f O t
ti
t C
di l Current ERC Guidelines. Available online: https:/ 9. Prabakaran, S.; Slappy, R.; Merchant, F. Supraventricular Tachycardia. In Handbook of Outpatient Cardiology; Springer International
Publishing: Cham, Switzerland, 2022; pp. 409–422.i pp
, X.; Liu, W.; Lin, X.; Peng, L.; Qiu, S.; Zhang, Q. Combined Modified Valsalva Maneuver with Ade 10. Xiao, L.; Ou, X.; Liu, W.; Lin, X.; Peng, L.; Qiu, S.; Zhang, Q. References Combined Modified Valsalva Maneuver with Adenosine
Supraventricular Tachycardia: A Comparative Study. Am. J. Emerg. Med. 2024, 78, 157–162. [CrossRef] [PubMed] 10. Xiao, L.; Ou, X.; Liu, W.; Lin, X.; Peng, L.; Qiu, S.; Zhang, Q. Combined Modified Valsalva Maneuver with Adenosine
Supraventricular Tachycardia: A Comparative Study. Am. J. Emerg. Med. 2024, 78, 157–162. [CrossRef] [PubMed]
11
Kotadia I D ; Williams S E ; O’Neill M Supraventricular Tachycardia: An Overview of Diagnosis and Management Clin Med 10. Xiao, L.; Ou, X.; Liu, W.; Lin, X.; Peng, L.; Qiu, S.; Zhang, Q. Combined Modified Valsalva Maneuver with Adenosine
Supraventricular Tachycardia: A Comparative Study. Am. J. Emerg. Med. 2024, 78, 157–162. [CrossRef] [PubMed] p
y
p
y
J
g
,
,
[
] [
]
11. Kotadia, I.D.; Williams, S.E.; O’Neill, M. Supraventricular Tachycardia: An Overview of Diagnosis and Management. Clin. Med. 2020, 20, 43–47. [CrossRef] [PubMed] 12. Littmann, L.; Olson, E.G.; Gibbs, M.A. Initial Evaluation and Management of Wide-Complex Tac
Practical Approach. Am. J. Emerg. Med. 2019, 37, 1340–1345. [CrossRef] [PubMed] 12. Littmann, L.; Olson, E.G.; Gibbs, M.A. Initial Evaluation and Management of Wide-Complex Tachycardia: A Simplified and
Practical Approach. Am. J. Emerg. Med. 2019, 37, 1340–1345. [CrossRef] [PubMed] g
p
y
pi
Practical Approach. Am. J. Emerg. Med. 2019, 37, 1340–1345. [CrossRef] [PubMed]
13. Narasimhan, B.; Gandhi, K.; Moras, E.; Wu, L.; Da Wariboko, A.; Aronow, W. Experimental Drugs for Supraventricular 13. Narasimhan, B.; Gandhi, K.; Moras, E.; Wu, L.; Da Wariboko, A.; Aronow, W. Experimental Dru
Tachycardia: An Analysis of Early Phase Clinical Trials. Expert Opin. Investig. Drugs 2023, 32, 825–838. 14. Ebrahimi, R.; Rubin, S.A. Electrical Cardioversion Resulting in Death from Synchronization Failure. Am. J. Cardiol. 1994, 74,
100–102. [CrossRef] [PubMed] 15. Xavier, L.C.; Memon, A. Synchronized Cardioversion of Unstable Supraventricular Tachycardia Resulting in Ventricular Fibrilla-
tion. Ann. Emerg. Med. 2004, 44, 178–180. [CrossRef] [PubMed] 16. Kaufmann, M.R.; McKillop, M.S.; Burkart, T.A.; Panna, M.; Conti, J.B.; Miles, W.M. Iatrogenic Ventricular Fibrillation after
Direct-Current Cardioversion of Preexcited Atrial Fibrillation Caused by Inadvertent T-Wave Synchronization. Tex. Heart Inst. J. 2018, 45, 39–41. [CrossRef] [PubMed] 17. Gallagher, M.M.; Yap, Y.G.; Padula, M.; Ward, D.E.; Rowland, E.; Camm, A.J. Arrhythmic Complications of Electrical Cardiover-
sion: Relationship to Shock Energy. Int. J. Cardiol. 2008, 123, 307–312. [CrossRef] [PubMed] p
gy
vutoglu, V.; Ozer, O. Electrical Cardioversion. Ann. Saudi Med. 2009, 29, 201–206. [CrossRef] [PubMed]i 18. Sucu, M.; Davutoglu, V.; Ozer, O. Electrical Cardioversion. Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual
author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to
people or property resulting from any ideas, methods, instructions or products referred to in the content. 22.
Doukky, R.; Bargout, R.; Kelly, R.F.; Calvin, J.E. Using Transcutaneous Cardiac Pacing to Best Advantage: How to Ensure
Successful Capture and Avoid Complications. J. Crit. Illn. 2003, 18, 219–225. [PubMed] References Ann. Saudi Med. 2009, 29, 201–206. [Cro 19. SIMS, J.J.; MILLER, A.W.; UJHELYI, M.R. Regional Hyperkalemia Increases Ventricular Defibrillation Energy Requirements. J. Cardiovasc. Electrophysiol 2000, 11, 634–641. [CrossRef] [PubMed] 20. Page, R.L.; Joglar, J.A.; Caldwell, M.A.; Calkins, H.; Conti, J.B.; Deal, B.J.; Estes, N.A.M.; Field, M.E.; Goldberger, Z.D.; Hammill,
S.C.; et al. 2015 ACC/AHA/HRS Guideline for the Management of Adult Patients With Supraventricular Tachycardia: Executive
Summary. Circulation 2016, 133, e471–e505. [CrossRef] [PubMed] y
21. Osmonov, D.; Erdinler, I.; Ozcan, K.S.; Altay, S.; Turkkan, C.; Yildirim, E.; Hasdemir, H.; Alper, A.T.; Cakmak, N.; Satilmis, S.; et al. Management of Patients with Drug-Induced Atrioventricular Block. Pacing Clin. Electrophysiol. 2012, 35, 804–810. [CrossRef]
[PubMed] 22. Doukky, R.; Bargout, R.; Kelly, R.F.; Calvin, J.E. Using Transcutaneous Cardiac Pacing to Best Advantage: How to Ensure
Successful Capture and Avoid Complications. J. Crit. Illn. 2003, 18, 219–225. [PubMed] Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual
author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to
people or property resulting from any ideas, methods, instructions or products referred to in the content.
|
W2947005429.txt
|
https://bnrc.springeropen.com/track/pdf/10.1186/s42269-019-0115-9
|
en
|
Evaluation of the benzo[a]anthracene biodegradation by animal bioassays
|
Bulletin of the National Research Centre/Bulletin of the National Research Center
| 2,019
|
cc-by
| 5,253
|
Partila and Mohammed Bulletin of the National Research Centre
https://doi.org/10.1186/s42269-019-0115-9
(2019) 43:72
Bulletin of the National
Research Centre
RESEARCH
Open Access
Evaluation of the benzo[a]anthracene
biodegradation by animal bioassays
Abir M. Partila1* and Manal R. Mohammed2
Abstract
Background: Benzo[a]anthracene (BAA), also known as “tetraphene” belongs to the polycyclic aromatic hydrocarbons
(PAHs) which are considered as an important class of environmental genotoxins. The present work focused on the
evaluation of the efficiency of the biodegradation of the BAA by Bacillus amyloliquefaciens using animal bioassays,
which include micronucleus (MN) and DNA fragmentation as end point of genotoxicity of the resulting metabolites
from BAA biodegradation.
Results: B. amyloliquefaciens was exposed to different doses of γ radiation (0.5, 1.0, 1.5, and 2.0 kGy) kGy. The colonies
for the wild strain and its variants obtained after radiation were counted. The final counts for variant 3 (V3), variant 4
(V4), and variant 5 (V5) have been increased from its initial count by (0.3, 0.48, and 0.1 log cycle) respectively at 1 mg/
100 ml (BAA). For animal bioassay, male mice were divided into seven groups; control group received vehicle only,
groups II and III were injected with 5 and 10 mg/kg b.wt (BAA) respectively, and groups IV, V, VI, and VII were injected
with the residues of BAA after biodegradation with wild type, V3, V4, and V5 of B. amyloliquefaciens respectively.
Conclusions: Results of the micronucleus test and the DNA fragmentation as end point of genotoxicity of
(BAA) indicated that B. amyloliquefaciens have the efficiency in biodegradation of (BAA) to nongenotoxic
metabolites where (V3) and (V4) are more efficient than the wild type and (V5). So B. amyloliquefaciens could
solve the problem of soil and water contamination by oil spill or industrial petroleum waste by ecofriendly
manner.
Keywords: BAA, Genotoxicity, Bacillus amyloliquefaciens, DNA fragmentation, Micronucleus, Biodegradation
Introduction
Polycyclic aromatic hydrocarbons (PAHs) are considered
as pollutants which consist of two or more fused aromatic rings. It formed after incomplete combustion of
the organic materials such as fossil fuels, wood, or coal,
also present in the smoke of cigarette (Li et al. 2018). It
found in different environment places as fresh water,
marine sediment, sand, and also in the atmosphere.
These environmental pollution has a global concern;
this is because almost all PAHs are highly toxic, mutagenic, and carcinogenic to humans, plant, and also to
microorganisms (Rengarajan et al. 2015). Wiley (2012)
mentioned the genotoxicity and carcinogenicity to benzo[a]anthracene (BAA). Jacob et al. (1983) proved that
* Correspondence: abir2partila@yahoo.com
1
Radiation Microbiology Deparment, National Centre for Radiation Research
and Technology (NCRRT), Egyptian Atomic Energy Authority, P. O. Box 29,
Nasr City, Egypt
Full list of author information is available at the end of the article
the formation of epoxides and dihydrodiolsas is a result
of BAA metabolization. The PAHs metabolizing enzymes are present in all tissues and are involved in detoxification of BAA as indicated by Slooff et al. (1989).
DNA adducts were formed in epithelial cells and blood
lymphocytes, and unscheduled DNA synthesis was observed in HeLa cells; in addition, BAA was found to be
genotoxic in many different organisms in vivo (McCarrick et al. 2019). Toxic effects of BAA, benzo-a-pyrene
(BAP) and naphthalene were described in experimental
embryo of animals and laboratory studies conducted on
mice have demonstrated that ingestion of high levels of
BAP during pregnancy results in birth defects and a decreased body weight in the offspring (Ng et al 2009).
Also, the Environmental Protection Agency (EPA) has
classified the following seven PAH compounds as being
one of the cause of human carcinogens: BAA, BAP,
benzo(b) fluoranthene, benzo(k)fluoranthene, chrysene,
© The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made.
Partila and Mohammed Bulletin of the National Research Centre
(2019) 43:72
dibenz[a,h]anthracene, and indeno (1,2,3-cd) pyrene
(Ramesh et al. 2010).
Bone marrow where the rapid cell proliferation occurs
is the most preferred organ for the evaluation of genotoxicity of different chemicals (Vikram et al. 2007). The
micronucleus (MN) test is widely used for screening the
genotoxic potential of different agents (Asanami et al.
1995). Micronuclei are formed in dividing cells due to
either a compound’s interaction with DNA leading to
breakage of chromosome or of its interaction with
non-DNA targets leading to loss of chromosome (De
Boeck et al. 2005). This bioassay is recommended for
genotoxicity evaluation and has become increasingly
common for regulatory acceptance. For the in vivo genotoxicity studies, the mice is preferred than the rats
(Ramirez-Munoz et al. 1999).
Microbial degradation is considered to be the main
process involved in the bioremediation of PAH (Yuan et
al. 2002). This method was better than physical and
chemical such as combustion, photolysis, and ultrasonic
decomposition; this is due to their ecofriendly and environmental way for removal of PAHs (Toledo et al. 2006).
Some microorganisms have the ability to utilize PAHs as
a source of carbon and energy and degraded them to
carbon dioxide and water, or transformed to other nontoxic or low-toxic substances (Perelo 2010).
Partila (2013) determined BAA degradation percentage
by different isolates with HPLC and indicated that the
best BAA degrader was MAM-62; this isolate degraded
39% of 500 μg/L BAA. And identified by DNA sequencing as Bacillus amyloliquefaciens with accession No.
Page 2 of 7
JN03805, Bacillus amyloliquefaciens is a non-pathogenic
soil bacterium capable of producing endospores allowing
it to survive.
For extended periods of time, it also shows some antifungal properties which are influenced by environmental
nitrogen availability (Caldeira et al. 2008).
Also the intermediates as determined by GC-MS analysis of BAA degradation by B. amyloliquefaciens after
24-h incubation are hexanoic acid, hepatanoic acid,
benzeneethanol, hexanoic acid,2-ethyl, octanoic acid,
nonanoic acid, indol-5-aldhyde, n-hexadecanoic acid,
benz(a)anthracene 7,12 dione, and b-sitosterol acetate
(Partila 2013). The proposed pathway for degradation of
BAA by B. amyloliquefaciens, as shown in Fig. 1, considered as novel pathway for the bacterial metabolism of
BAA. This pathway contains a set of metabolites, not
present in previously known pathways, like benzo[a]quinone, phthalic acid, phthalicaciddehydroxy, phthalic acid
methylester, hydroxytetralone, naphthalonedione and
dihydroxy naphthalene (Cajthaml et al. 2006), and
BAA-dihydrodiol (Schneider et al. 1996). Also, the variants showed better results than a wild type; this may be
due to a variety and increasing of enzymes which increase the rate of biodegradation for BAA. The parent
strain MAM-62 produced nine intermediates. However,
the mutant strain MAM-62(4) produced 15 intermediates (Partila 2013).
So, the aim of this work is to evaluate the efficiency of
Bacillus amyloliquefaciens for biodegradation of the
(BAA) by using micronucleus (MN) and DNA fragmentation as end point of BAA genotoxicity.
Fig. 1 Proposed pathway of benzo-a-anthracene degradation by B. amyloliquefaciens (Partila 2013)
Partila and Mohammed Bulletin of the National Research Centre
(2019) 43:72
Material and methods
Bacillus amyloliquefaciens culture media and treatments
The bacterial strain was Bacillus amyloliquefaciens with
accession No. JN038054. BAA was purchased from
(AcRos organics, New Jersey, USA). B. amyloliquefaciens
was inoculated in LB (Luria-Bertani) broth medium prepared according to Martin et al. 1981 and incubated at
30 °C for 24 h in shaking incubator. The well grown bacterial culture were centrifuged at 8000 rpm for 10 min
and washed twice with basal salt media (BSM) (Ogawa
and Miyashita 1995). The washed bacterial cells were resuspended in BSM supplemented with 1 mg/100 ml
BAA. The bacterial count for the bacterial culture was
determined after 7 days incubation to confirm their ability to grow and degrade the compound.
Effect of gamma radiation on the viability of the most
potent strain
B. amyloliquefaciens was grown in LB broth medium for
24 h at 37 °C in shaking incubator (150 rpm). The well
grown bacterial cells were harvested by centrifugation at
8000 rpm for 10 min then washed and resuspended in
sterile saline. Cell suspensions were distributed into
5.0 ml sterile screw capped test tubes and then exposed
to different doses of gamma radiation (0.5, 1.0, 1.5, and
2.0 kGy) (Indian cell Co-60) with dose rate kGy/15 min
in the National Center for Radiation Research and Technology (NCRRT), Nasr City, Cairo, Egypt. Three replicates were used for each dose. Serial dilution and pore
plate technique were established. The plates were incubated at 30 °C for 24 h. The changes in morphological
characters (color, shape, margin, size) of the colonies at
different doses were picked up as variants.
Each picked irradiated bacterial colony was inoculated in LB broth medium and incubated at 30 °C for
24 h in shaking incubator along with the wild type B.
amyloliquefaciens.
The well-grown bacterial culture were centrifuged at
8000 rpm for 10 min and washed twice with BSM.
The washed bacterial isolated strains were used to inoculate 100 ml BSM in 250 ml conical flask amended
with 0.5 mg of BAA. Three replicates were used for each
concentration for each strain. The inoculated flasks were
incubated at 30 °C in shaking incubator.
Samples were examined for O.D. at 600 nm by using
spectrophotometer (LW-V-200 RS UV/Vis., Germany)
and for count of cells (CFU/ml) at the beginning and
after 1, 2, 7, 14, and 21 days incubation (Partila 2013).
Experimental animals and treatments
Swiss albino male mice weighting 20–25 g were obtained
from National Center for Radiation Research and Technology, Cairo, Egypt. They were housed in steel mesh
cages in a temperature of 25–30 °C with alternating 12 h
Page 3 of 7
light and dark cycles and allowed free access to standard
diet and tap water. The animals were housed five mice
per cage and randomly divided into seven groups, five
mice for each group. Group I was used as control
treated with the vehicle only i.p.(0.1 ml DMSO diluted
with 0.2 ml saline). Groups II and III were injected by
(BAA), which was dissolved in the vehicle, at dose of 5
and 10 mg/kg b.wt. respectively. Groups VI, V, VI, and
VII were injected i.p. with the residues of the equivalent
dose of 10 mg/kg b.wt. after biodegradation with wild
type, V3, V4, and V5.
Micronucleus assay
The animals were sacrificed after 24 h of treatment and
the bone marrow was collected for the micronucleus
assay (Schmid 1975) modified from the femurs were
washed with 2 ml of fetal calf serum (Sigma) in a centrifuge tubes, homogenizing the cell suspension, and
centrifuging it at 1000 rpm for 10 min, after which the
supernatant was partially discarded to leave few drops of
fetal calf serum in which the cell pellet was
re-suspended and then smeared on clean and dry slides,
which then fixed with absolute methanol for 10 min and
stained for 8 min with 5% (v/v) Giemsa stain diluted
with phosphate buffer (Na2HPO4 0.06 M and KH2PO4
0.06 M, pH 6.8). For each animal, 1500 polychromatic
erythrocytes (PCEs) were analyzed to ascertain the frequencies of micronuclei and micronucleated cells in
mice exposed to the different treatments. The slides
were scored blindly according to the established criteria
(Titenko-Holland et al. 1997). Microscopic examination
was done under oil immersion using (LeitzWetzlar,
Germany)—Orthomat binocular optical microscope with
magnification × 1000.
DNA fragmentation assay by diphenylamine
Quantification of fragmented DNA was estimated by diphenylamine (DPA) assay. The method was carried out
according to Perandones et al. (1993). Cell lysates was
obtained by mechanically dissociation of 0.5 g. of liver in
400 μl hypotonic lysis buffer which was prepared by dissolving 5 mM, tris HCl, 20 mM EDTA, and 0.5%
Triton-100 in distilled water then the solution was adjusted to 100 ml. The cell lysates were centrifuged then
the supernatant containing small DNA fragmentations
was removed in another tubes and the pellet containing
large pieces of DNA and cell debris was left in the tubes,
then the reagent was added as following TCA 10% then
centrifuge; the precipitate was resuspended in 400 μl 5%
TCA. The tubes were incubated in boiling water for
30 min and then were centrifuged. The extracted DNA
was left to cool at room temperature. Further, 1 ml DPA
solution (0.88 M diphenylamine dissolved in 98% glacial
acetic acid) then 1.5% concentrated sulfuric acid was
Partila and Mohammed Bulletin of the National Research Centre
(2019) 43:72
Page 4 of 7
added to the solution. This solution was stored in a dark
glass bottle. On the day of use, 0.5% of freshly prepared
(1.6% v/v acetaldehyde) was added to 0.5 ml of extracted
DNA and the samples were kept at 4 °C for 48 h. The
absorbance of samples was recorded at 578 nm. The
percentage of DNA fragmentation was expressed by the
formula:
Table 2 The counts of the wild type of B. amyloliquefaciences
and the variants at initial and after 21 days incubation. (p = 0.05)
%DNA fragmentation ¼
½O:D:of supernatant=ðO:D:of supernatant þ O:D:of pelletÞ 100
Strains
wild type
Initial count Log N
6
120 × 10
8.79 ± 0.04
Count after 21 days
LogN
6
7.51 ± 0.05a
6
33 × 10
V1
6
36 × 10
7.55 ± 0.03
06 × 10
6.77 ± 0.07a
V2
18 × 106
7.25 ± 0.05
03 × 106
6.47 ± 0.07a
V3
6
36 × 10
7.55 ± 0.01
6
76 × 10
7.88 ± 0.04 a
V4
27 × 106
7.43 ± 0.03
83 × 106
7.91 ± 0.01 a
V5
6
7.50 ± 0.05
6
32 × 10
40 × 10
7.60 ± 0.06
a
Means a significant log N after 21 days incubation with log N at initial time
for the same isolate and Log N for V3, V4 and V5 were more than the rest
Statistical analysis
The data obtained in the present work were represented
as mean ± standard deviation. Statistical analysis was carried out using (Statistical Package for Social Science)
(SPSS) software version 20 for windows; significant differences among groups were evaluated using one-way
analysis of variance (one-way ANOVA); least-significant
difference (LSD) was used for multi-group comparisons.
P values ≤ 0.05 were considered as significant (Festing
and Altman 2002).
Results
The bacterial growth and count
The growth of B. amyloliquefaciens wild type and its variants in 1 mg/100 ml BAA as indicated in Table 1 cleared a
variation in the O.D., but in all samples the final OD was
not higher than the initial OD so in this experiment, it was
not recognized which sample can get the highest growth
under the effect of BAA, which could be cleared in the bacterial count experiment. Table 2 indicated that the initial
count in 1 mg/100 ml BAA for variants (V1 and V2) was
(36 × 106 and 18 × 106 CFU/ml) respectively. It was cleared
to be more than its count after 21 days incubation (6 × 106,
3 × 106CFU/ml) respectively. But for the other variants V3,
V4, and V5, the count after 21 days incubation was (76 ×
106, 83 × 106, and 40 × 106 CFU/ml) respectively exceeding
their initial count (36 × 106, 27 × 106, and 32 × 106 CFU/ml)
respectively. According to these results, only V3, V4, and
V5 were chosen for further evaluation by animal bioassay.
Effect of BAA on the formation of micronuclei
As shown in Table 3, a significant increases in the percent of micronuclei induction in the groups that were
injected with (BAA) at different doses as compared with
the control group. As expected, the significant increase
in the total number of the cells with MN, mononucleated cells, binucleated cells, and multinucleated cells was
proportionally related to the dose of (BAA). On the
other hand, the genotoxic effect of (BAA) residue, after
biodegradation with wild and variant types of bacteria,
was significantly lower than that before biodegradation
but still significantly higher than that of control group
except for the groups of variant 3 and variant 4 which
have non-significant genotoxic effect as compared with
the control group.
Effect of BAA on the % of DNA fragmentation
The percentage of DNA fragmentation increased proportionally with increasing the dose of BAA as shown in
Fig. 2. The genotoxic effect of BAA significantly reduced
after the biodegradation with wild and variant types of
bacteria as compared with that before biodegradation.
Meanwhile, the residue of biodegradated BAA with V3
and V4 has insignificant genotoxic effect as compared
with control group; the residue from V5 is still significantly higher as compared with control group.
Table 1 The growth of the wild type and variants during 21 days incubation. Data expressed as mean ± standard deviation
Variants
OD 600 of the Variants
Initial (zero time)
1 days
2 days
7 days
14 days
21 days
Wild type
1.40 ± 0.20
1.15 ± 0.01
1.17 ± 0.03
1.02 ± 0.03
0.87 ± 0.01a
0.87 ± 0.05a
V1
1.07 ± 0.02
0.92 ± 0.03
0.96 ± 0.03
0.78 ± 0.01
0.75 ± 0.00
0.64 ± 0.06 a
V2
1.12 ± 0.03
0.87 ± 0.02
0.87 ± 0.05
0.71 ± 0.08
0.67 ± 0.01
0.60 ± 0.08a
a
V3
0.96 ± 0.01
0.81 ± 0.03
0.64 ± 0.01
0.42 ± 0.05
0.33 ± 0.03
0.39 ± 0.00
V4
1.07 ± 0.04
0.97 ± 0.09
0.96 ± 0.01
0.59 ± 0.01
0.42 ± 0.06a
0.50 ± 0.06
V5
a
1.06 ± 0.06
0.88 ± 0.01
0.88 ± 0.04
a
0.56 ± 0.04
a
0.57 ± 0.02
0.57 ± 0.02a
symbol mean the result of O D is significant from the initial for the same strain. The mean difference is significant at the 0.05 level. Data expressed as mean ±
standard deviation significant results indicate OD decreased at that day as compared by the initial day for the same strain
Partila and Mohammed Bulletin of the National Research Centre
(2019) 43:72
Page 5 of 7
Table 3 The effect of (BAA) or its residues after biodegradation by different types of bacteria on the induction of MN. Showing MN
cells: total cells with MN, Mono-MN cells: with one MN, Bi-MN cells: with two MN, Multi-MN cells: with more than two MN. p < 0.05)
Group
No. of cells
examined
Mean ± SD of percentages
Normal cells
MN cells
Mono-MN cells
Bi-MN cells
Multi-MN cells
DMSO
7516
99.57 ± 0.04
0.43 ± 0.04
0.17 ± 0.04
0.23 ± 0.10
0.03 ± 0.04
(BAA) 5 mg/kg b.wt.
7517
97.59 ± 0.38ab
2.41 ± 0.38ab
1.56 ± 0.27ab
0.64 ± 0.08ab
0.21 ± 0.10ab
(BAA) 10 mg/kg b.wt.
7510
92.93 ± 0.29a
7.07 ± 0.29a
3.57 ± 0.13a
2.36 ± 0.15a
1.15 ± 0.26a
ab
ab
ab
ab
Wild + 10 mg/kg b.wt.
7524
95.81 ± 0.25
4.19 ± 0.25
2.35 ± 0.31
1.33 ± 0.16
0.51 ± 0.19ab
V3 + 10 mg/kg b.wt.
7520
99.35 ± 0.06b
0.65 ± 0.06b
0.33 ± 0.05b
0.27 ± 0.05b
0.05 ± 0.03b
V4 + 10 mg/kg b.wt.
7523
b
99.38 ± 0.08
b
0.62 ± 0.08
b
0.37 ± 0.08
b
0.20 ± 0.08
0.05 ± 0.06b
V5 + 10 mg/kg b.wt.
7515
99.15 ± 0.09ab
0.85 ± 0.09ab
0.49 ± 0.04ab
0.29 ± 0.08b
0.07 ± 0.05b
a
Comparison with DMSO
Comparison with 10 mg/kg b.wt
b
Discussion
Many studies previously showed that MN is a biomarker
of chromosomal damage, but now we should reconsider
MN as an important cause of genetic variation that may
be critical during the genesis of some diseases and cancer (Bayram et al. 2016). Chromothripsis, a sole pattern
of localized chromosome rearrangements and it was suggested that DNA damage from MN could lead to a moderate level of rearrangement (Zhang et al. 2015). As
indicated in Table 1, the variation of O.D. may be due to
the interference between the yellow color of BAA and
the turbidity of the B. amyloliquefaciens growth, so as
Juhasz et al. (1997) observed that the culture supernatant turned to a yellow color when BAA was utilized
as a sole carbon and energy source. In addition, the decrease in the amount of PAH was evidenced by a color
change in the medium and was approved by GC-MS
analysis of BAA degradation by B. amyloliquefaciens as
was mentioned by Partila (2013).
Bacteria initiate PAH degradation by the action of
intracellular dioxygenases; the PAHs must be taken up
by the cells before degradation takes place (Smith 1990).
In the present study, the count after incubation time as
indicated in Table 2 was less than the initial in the case
of wild, V1, and V2; this may be due to the decrease of
the enzymes necessary for the consumption of the compound. While in the case of V3, V4, and V5, the final
count were more than the initial, better than the wild
type, V1, and V2; this may be due to the sufficient enzymes which are secreted by these variants that might
play an important role in the transformation and the
degradation of BAA.
PAH dioxygenase (PDO) and catechol 2,3-oxyenase
(C23O) are identified as two key PAH-degrading-related
enzymes (Meyer et al. 1999). However, to the best of our
knowledge, there is no information regarding the simultaneous change of these key enzyme activities in a biodegradation process (Grifoll et al. 1995).
Fig. 2 The effect of (BAA) or its residues after biodegradation by different types of bacteria on the % of the DNA fragmentation. (p < 0.05), a: comparison
with DMSO group, b: comparison with (BAA)10 mg/kg bwt. group
Partila and Mohammed Bulletin of the National Research Centre
(2019) 43:72
Ting et al. (2011) showed that the degradation rate
constants for phenanthrene and pyrene increased when
the PAH concentration in the cultures contains (from 2
to 50 mg/lPAHs). But, at the level of 100 mg/l, the degradation rate does not change due to the failure of the
organism to degrade the remaining PAHs after 6 days. It
appears that the organism entered an inactive phase
after 6 days incubation in the liquid culture.
It is well known that very few organisms have been
able to degrade a single compound completely (You-Qing et al. 2008). Bacillus cereus and Bacillus megaterium
were observed consuming 65.8% and 33.7% of pyrene
(50 mg/l) within 3 weeks, respectively.
The results of control group presented micronucleated
cells < 3/100 cells which are the normal value of the
mean spontaneous micronucleus frequency (Salamone
and Mavournin 1994). The present data is in agreement
with many previous studies indicated that bone marrow
cells of mice are susceptible to the genetic damaging action of BAA. This damage is due to the effect of metabolites of BAA which have been indicated for their ability
to induce mutations, cell transformation, and form nucleic acid adducts covalently (Conney 1982). Even without external metabolic activation, BAA caused DNA
strand breaks (Platt et al. 2008). The 3,4-diol-1,2-epoxide
metabolite is mutagenic; its metabolic precursor, the
3,4-dihydrodiol, is also mutagenic. The 3,4-dihydrodiol
and a 3,4-diol-1,2-epoxide also have high carcinogenic
activity (Li et al. 2018). DNA analysis from skin of mice
or cultured cells treated with BAA indicates that a
3,4-diol-1,2-epoxide and a 8,9-diol-10,11-epoxide form
nucleic acid adducts covalently (IARC 1972).
For some metabolites from other work like benz[a]anthracene-trans-3,4-dihydrodiol (BA-3,4-dihydrodiol) which consider the minor metabolite getting
from BAA, it shows higher mutagenicity and tumorigenicity than parent BAA; this cause the damage of
DNA. Its liberation enhanced by addition of NADH.
Also, BA o-quinone type metabolite, benz[a]anthracene-3,4-dione (BA-3,4-dione) both induced oxidative
DNA damage in the presence of cytochrome P450 reductase (Seike et al. 2003). Cooper et al. (1980) declared that diol-epoxide for anthracene thought to be
involved in the binding of BAA to DNA in some situations reacts mainly with deoxyguanosine.
Conclusions
From the results of the present study, it could be concluded that B. amyloliquefaciens and its variants have
the efficiency in biodegradation of (BAA), which are
considered as an important class of environmental genotoxins; this is confirmed by micronucleus (MN) and
DNA fragmentation as end point of genotoxicity of BAA
and its resulting metabolites. So, B. amyloliquefaciens
Page 6 of 7
may be used for degradation of BAA in contaminated
water and soil by oil spill or industrial petroleum waste.
Abbreviations
BAA: Benzo[a]anthracene; MN: Micronucleus
Acknowledgements
The authors acknowledge the radiation department at NCRRT Cairo, Egypt.
Funding
Not applicable.
Availability of data and materials
I agree to be the data available to “Bulletin of the National Research Centre”
for publication.
Authors’ contributions
AMP subcultured Bacillus amyloliquefaciens and test for b-a-anthracene
degradation, then apply the organism to gamma radiation. Test wild and
variants for degradation of the compound. Then bring the wild strains and
its variants to MRM. MRM inject mice and made micronucleus (MN) and
DNA fragmentation test to declare the effect of radiation for getting variant
can degrade b-a-anthracene more than wild strain. Both MRM and AMP
participate in writing their parts and MRM reviews the text. Both authors read
and approved the final manuscript.
Ethics approval and consent to participate
All authors agree to participate according to the ethics.
Consent for publication
All authors agree for publication at “Bulletin of the National Research Centre”.
Competing interests
The authors declare that they have no competing interests.
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published
maps and institutional affiliations.
Author details
1
Radiation Microbiology Deparment, National Centre for Radiation Research
and Technology (NCRRT), Egyptian Atomic Energy Authority, P. O. Box 29,
Nasr City, Egypt. 2Radiation Biology Deparment, National Centre for Radiation
Research and Technology (NCRRT), Egyptian Atomic Energy Authority, P. O.
Box 29, Nasr City, Egypt.
Received: 11 December 2018 Accepted: 8 April 2019
References
Asanami S, Shimono K, Sawamoto O, Kurisu K, Uejima M (1995) The suitability of
rat peripheral blood in subchronic studies for the micronucleus assay. Mutat
Res 347:73–78.
Bayram SE, Rencüzoğullar A, Almas M, Genc A (2016) Effect of p53 Arg72Pro
polymorphism on the induction of micronucleus by aflatoxin B1 in in vitro in
human blood lymphocytes. Drug Chem Toxicol 39:331–337.
Cajthaml T, Erbanová P, Šašek V, Moeder M (2006) Breakdown products on
metabolic pathway of degradation of benz[a]anthracene by a ligninolytic
fungus. Chemosphere. 64(4):560–564.
Caldeira AT, Feio SS, Arteiro JMS, Coelho AV, Roseiro JC (2008) Environmental
dynamics of Bacillus amyloliquefaciens CCMI 1051 antifungal activity under
different nitrogen patterns. J Appl Microbiol 104(3):808–816.
Conney AH (1982) Induction of microsomal enzymes by foreign chemicals and
carcinogenesis by polycyclic aromatic hydrocarbons: G.H.A. Clowes memorial
lecture. Cancer Res 42:4875–4917.
Cooper CS, Ribeiro O, Farmer PB, Hewer A, Walsh C, Pal K et al (1980) The
metabolic activation of benz[a]anthracene in hamster embryo cells: evidence
that diol-epoxides react with guanosine, deoxyguanosine and adenosine in
nucleic acids. Chem Biol Interact 32(1–2):209–231.
Partila and Mohammed Bulletin of the National Research Centre
(2019) 43:72
De Boeck M, Van der Leede B, Van Goethem F, De Smedt A, Steemans M, Lampo
A et al (2005) Flow cytometric analysis of micronucleated reticulocytes: timeand dose-dependent response of known mutagens in mice, using multiple
blood sampling. Environ Mol Mutagen 46(1):30–42.
Festing MF, Altman DG (2002) Guidelines for the design and statistical analysis of
experiments using laboratory animals. ILAR J 43(4):244–258.
Grifoll M, Selifonov SA, Gatlin CV, Chapman PJ (1995) Actions of a versatile
fluorene-degrading bacterial isolate on polycyclic aromatic compounds. Appl
Environ Microbiol 61(10):3711–3723.
IARC (1972) Monographs on the evaluation of the carcinogenic risk of chemicals
to humans. W Health Organiz .Int Agen for Res on Cancer, Geneva.
Jacob J, Schmoldt A, Raab G, Hamann M, Grimmer G (1983) Induction of specific
monooxygenases by isosteric heterocyclic compounds of benz[a]anthracene,
benzo[c]phenanthrene and chrysene. Canc Lett 20(3):341–348.
Juhasz AL, Britz ML, Stanley GA (1997) Degradation of fluoranthene, pyrene,
benzo(a)anthracene and dibenz(a,h)anthracene by Burkholderiacepacia. J
Appl Microbiol 83(2):189–198.
Li B, Ou P, Wei Y, Zhang X, Song J (2018) Polycyclic aromatic hydrocarbons
adsorption onto graphene: a DFT and AIMD study. Mat 11(5):726.
Martin PA, Lohr JR, Dean DH (1981) Transformation of Bacillus thuringiensis
protoplasts by plasmid deoxyribonucleic acid. J Bacteriol 145:980–983.
McCarrick S, Cunha V, Zapletal O, Vondráček J, Dreij K (2019) In vitro and in vivo
genotoxicity of oxygenated polycyclic aromatic hydrocarbons. Environ Poll
246:678–687.
Meyer S, Moser R, Neef A, Stahl U, Kämpfer P (1999) Differential detection of key
enzymes of polyaromatic-hydrocarbon-degrading bacteria using PCR and
gene probes. Microbiology. 145:1731–1741.
Ng SP, Conklin NSDJ, Bhatnagar AA, Bolanowski DD, Lyon J, Zelikoff JT (2009)
Prenatal exposure to cigarette smoke induces diet- and sex dependent
dyslipidemia and weight gain in adult murine offspring. Environ Health
Perspect 117(7):1042–1048.
Ogawa N, Miyashita K (1995) Recombination of a 3-chlorobenzoatecatabolic
plasmid from Alcaligeneseutrophus NH9 mediated by directrepeatelements.
Appl Environ Microbiol 61:3788–3795.
Partila AM. Biodegradation of polycyclic aromatic hydrocarbons in petroleum oil
contaminating the environment. 2013; Ph.D. thesis, faculty of science, Cairo
University.
Perandones CE, IlleraVA PD, Stunz LL, Ashman RF (1993) Regulation of apoptosis
in vitro in mature murine spleen T cells. J Immunol 151:3521–3529.
Perelo LW (2010) Review: in situ and bioremediation of organic pollutants in
aquatic sediments. J Haz Mat 177:81–89.
Platt KL, Aderhold S, Kulpe K, Fickler M (2008) Unexpected DNA damage caused
by polycyclic aromatic hydrocarbons under standard laboratory conditions.
Mutat Res 650(2):96–103.
Ramesh A, Archibong AE, Niaz MS (2010) Ovarian susceptibility to
benzo[a]pyrene: tissue burden of metabolites and DNA adducts in F-344 rats.
J Toxicol Environ Health A 73(23):1611–1625.
Ramirez-Munoz MP, Zuniga G, Torres-Bugarin O, Portilla E, Garcia-Martinez D,
Ramos A et al (1999) Evaluation of the micronucleus test in peripheral blood
erythrocytes by use of the splenectomized model. Lab AnimSci 49:418–420.
Rengarajan T, Rajendran P, Nandakumar N, Lokeshkumar B, Rajendran P, Nishigaki
I (2015) Exposure to polycyclic aromatic hydrocarbons with special focus on
cancer. Asian Pac J Trop Biomed 5(3):182–189.
Salamone MF, Mavournin KH (1994) Bone marrow micronucleus assay: a review
of the mouse stocks used and their published mean spontaneous
micronucleus frequencies. Environ Mol Mutagen 23:239–273.
Schmid W (1975) The micronucleus test. Mutat Res 31:9–15.
Schneider J, Grosser R, Jayasimhulu K, Xue W, Warshawsky D (1996) Degradation
of pyrene, bezo(a) anthracene, and benzo(a) pyrene by Mycobacterium sp.
strain RJGII-135, isolated from a former coal gasification site. Appl Environ
Microbiol 62(1):13–19.
Seike K, Murata M, Oikawa S, Hiraku Y, Hirakawa K, Kawanishi S (2003) Oxidative
DNA damage induced by benz[a]anthracene metabolites via redox cycles of
quinone and unique non-quinone. Chem Res Toxicol 16(11):1470–1476.
Slooff W, Janus JA, AJCM M, Montizaan CK, Ros JP (1989) Integrated criteria
document PAH. Report No. 758474011. National Institute of Public Health
and Environmental Protection, Bilthoven.
Smith MR (1990) The biodegradation of aromatic hydrocarbons by bacteria.
Biodegr. 1:191–206.
Ting WTE, Yuan SY, Wu SD, Chang BV (2011) Biodegradation of phenanthrene
and pyrene by Ganodermalucidum. Int Biodeter Biodegr 65:238–242.
Page 7 of 7
Titenko-Holland N, Windham G, Kolachana P, Reinisch F, Parvatham S, Osorio AM
et al (1997) Genotoxicity of malathion in human lymphocytes assessed using
the micronucleus assay in vitro and in vivo: a study of malathion exposed
workers. Mutat Res 338:85–95.
Toledo FL, Calvo C, Rodelasand B, González-López J (2006) Selection and
identification of bacteria isolated from waste crude oil with polycyclic
aromatic hydrocarbons removal capacities. Syst Appl Microbiol 29(3):
244–252.
Vikram A, Ramarao P, Jena G (2007) Prior bleeding enhances the sensitivity of
peripheral blood and bone marrow micronucleus tests in rats. Mutagenesis
22(4):287–291.
Wiley V (2012) The MAK-collection part I: occupational toxicants. Wiley-VCH
Verlag Gmb H & Co. KGa A.; 27 DFG, Deutsche Forschungsgemeinschaft.
You-Qing LI, Hong-Fang LIU, Zhen-Le TIAN, Li-Hua ZHU, Ying-Hui WU, He-Qing
TANG (2008) Diesel pollution biodegradation: synergetic effect of
Mycobacterium and filamentous Fungi1. Biomed Environ Sci 21(3):181–187.
Yuan SY, Shiung LC, Chang BV (2002) Biodegradation of polycyclic aromatic
hydrocarbons by inoculated microorganisms in soil. Bull Environ ContToxicol
69:66–73.
Zhang CZ, Spektor A, Cornils H, Francis JM, Jackson EK, Liu S et al (2015)
Chromothripsis from DNA damage in micronuclei. Nature. 522:179–184.
|
|
https://openalex.org/W2274986878
|
https://trialsjournal.biomedcentral.com/counter/pdf/10.1186/1745-6215-16-S2-P41
|
English
| null |
Implementing electronic data capture (EDC) training for site staff
|
Trials
| 2,015
|
cc-by
| 514
|
Background ICR-CTSU introduced EDC in 2012 necessitating the
development of EDC specific training materials for
participating sites. Published: 16 November 2015
doi:10.1186/1745-6215-16-S2-P41
Cite this article as: Webster-Smith et al.: Implementing electronic data
capture (EDC) training for site staff. Trials 2015 16(Suppl 2):P41. Development of training materials ICR-CTSU created a custom EDC system user guide,
developed training slides and included instructional text
within the EDC system. Since the implementation of EDC,
ICR-CTSU have developed short training videos covering
key topics including logging in, record navigation, data
entry and query response. The videos illustrate the EDC
screen view and are accompanied by scripted voice over
guidance. Training materials are accessible online via the
ICR-CTSU website. Submit your next manuscript to BioMed Central
and take full advantage of:
• Convenient online submission
• Thorough peer review
• No space constraints or color figure charges
• Immediate publication on acceptance
• Inclusion in PubMed, CAS, Scopus and Google Scholar
• Research which is freely available for redistribution
Submit your manuscript at
www.biomedcentral.com/submit
ss article distributed under the terms of the Creative Commons Attribution License
ch permits unrestricted use, distribution, and reproduction in any medium, provided
Commons Public Domain Dedication waiver (http://creativecommons.org/
e available in this article, unless otherwise stated. Open Access Open Access Challenges Training of site staff on EDC systems is essential to
ensure data quality and returns are maximised. Guidance
notes are issued to support standardised completion of
case report forms. However, due to the technical nature
of EDC, guidance notes alone provide insufficient sup-
port for most site staff. Provision of effective, consistent
and timely EDC training across a trial’s lifespan is a con-
tinuing challenge, particularly for large trials or those
with long follow-up where site staff turnover is an added
consideration. doi:10.1186/1745-6215-16-S2-P41
Cite this article as: Webster-Smith et al.: Implementing electronic data
capture (EDC) training for site staff. Trials 2015 16(Suppl 2):P41. Implementing electronic data capture (EDC)
training for site staff Mark Webster-Smith*, Claire Paulding, Stephanie Burnett, Lisa Jeffs, Dalia Ismail, Carolyn McNamara, Sharon Ereira,
Rebecca Lewis, Emma Hall, Judith Bliss, Claire Snowdon From 3rd International Clinical Trials Methodology Conference
Glasgow, UK. 16-17 November 2015 and centre initiation visits, however the online training
videos provide a more consistent and accessible resource. This solution should reduce demand on ICR-CTSU
resources for ongoing site training. TRIALS TRIALS Webster-Smith et al. Trials 2015, 16(Suppl 2):P41
http://www.trialsjournal.com/content/16/S2/P41 The Institute of Cancer Research Clinical Trials & Statistics Unit (ICR-CTSU),
London, UK Conclusions Whilst customised EDC system user guides and in-built
instructions form the basis of site staff training, supplemen-
tary technical training is required. This can be provided to
site staff individually through webinars, teleconferences The Institute of Cancer Research Clinical Trials & Statistics Unit (ICR-CTSU),
London, UK © 2015 Webster-Smith et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License
(http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided
the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/
publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
|
https://openalex.org/W4385831141
|
https://journal.svmo.ru/en/downloads/article?article_id=1769
|
Russian
| null |
Energy Function for Direct Products of Discrete Dynamical Systems
|
Žurnal Srednevolžskogo matematičeskogo obŝestva
| 2,023
|
cc-by
| 5,321
|
DOI 10.15507/2079-6900.25.202302.11-21
Оригинальная статья Оригинальная статья © М. К. Баринова, Е. К. Шустова Журнал Средневолжского математического общества. 2023. Т. 25, №2. Журнал Средневолжского математического общества. 2023. Т. 25, №2. 11 Контент доступен по лицензии Creative Commons Attribution 4.0 International License.
This is an open access article distributed under the terms of the Creative Commons
Attribution 4.0 International License. Математика ISSN 2079-6900 (Print)
ISSN 2587-7496 (Online) DOI 10.15507/2079-6900.25.202302.11-21
Оригинальная статья HSE University (Nizhny Novgorod, Russian Federation) Abstract. This paper is devoted to the construction of an energy function, i.e. a smooth
Lyapunov function, whose set of critical points coincides with the chain-recurrent set of
a dynamical system — for a cascade that is a direct product of two systems. One of
the multipliers is a structurally stable diffeomorphism given on a two-dimensional torus,
whose non-wandering set consists of a zero-dimensional non-trivial basic set without pairs
of conjugated points and without fixed source and sink, and the second one is an identical
mapping on a real axis. It was previously proved that if a non-wandering set of a dynamical
system contains a zero-dimensional basic set, as the diffeomorphism under consideration has,
then such a system does not have an energy function, namely, any Lyapunov function will
have critical points outside the chain-recurrent set. For an identical mapping, the energy
function is a constant on the entire real line. In this paper, it is shown that the absence of an
energy function for one of the multipliers is not a sufficient condition for the absence of such
a function for the direct product of dynamical systems, that is, in some cases it is possible to
select the second cascade in such a way that the direct product will have an energy function. Keywords: Direct product, diffeomorphism, chain recurrent set, energy function
For citation: M. K. Barinova, E. K. Shustova. Energy Function for Direct Products
of Discrete Dynamical Systems. Zhurnal Srednevolzhskogo matematicheskogo obshchestva. 25:2(2023), 11–21. DOI: https://doi.org/10.15507/2079-6900.25.202302.11-21 About the authors: Marina K. Barinova, Senior Research Fellow, National Research University «High School
of Economics» (25/12 B. Pecherskaya St., Nizhny Novgorod 603150, Russia), ORCID:
https://orcid.org/0000-0002-4406-583X, mkbarinova@yandex.ru
Evgenia K. Shustova, student, National Research University «High School of Economics»
(25/12 B. Pecherskaya St., Nizhny Novgorod 603150, Russia), ORCID: https://orcid.org/
0000-0002-4998-2186, ekshustova@gmail.com Marina K. Barinova, Senior Research Fellow, National Research University «High School
of Economics» (25/12 B. Pecherskaya St., Nizhny Novgorod 603150, Russia), ORCID:
https://orcid.org/0000-0002-4406-583X, mkbarinova@yandex.ru //
g/
y
Evgenia K. Shustova, student, National Research University «High School of Economics»
(25/12 B. Pecherskaya St., Nizhny Novgorod 603150, Russia), ORCID: https://orcid.org/
0000-0002-4998-2186, ekshustova@gmail.com //
/
Evgenia K. Shustova, student, National Research University «High School of Economics»
(25/12 B. Pecherskaya St., Nizhny Novgorod 603150, Russia), ORCID: https://orcid.org/
0000-0002-4998-2186, ekshustova@gmail.com M. K. Barinova, E. K. Shustova. Energy function for direct products of discrete dynamical systems Об энергетической функции для прямого
произведения дискретных динамических систем ациональный исследовательский университет «Высшая школа экономики»
. Нижний Новгород, Российская Федерация) Аннотация. Данная работа посвящена построению энергетической функции — глад-
кой функции Ляпунова, множество критических точек которой совпадает с цепно-
рекуррентным множеством динамической системы — для каскада, который являет-
ся прямым произведением двух систем. Один из сомножителей представляет собой
структурно устойчивый диффеоморфизм на двумерном торе, неблуждающее множе-
ство которого состоит из нульмерного нетривиального базисного множества без пар
сопряженных точек и неподвижных источника и стока, а второй является тождествен-
ным отображением на вещественной прямой. Ранее было доказано, что если неблуж-
дающее множество динамической системы содержит нульмерное базисное множество,
как у рассматриваемого диффеоморфизма, то такая система не обладает энергетиче-
ской функцией, а именно любая функция Ляпунова будет иметь критические точки
вне цепно-рекуррентного множества. Для тождественного отображения энергетическая
функция является константой на всей вещественной прямой. В данной работе показано,
что отсутствие энергетической функции для одного из сомножителей не является до-
статочным условием отсутствия такой функции у прямого произведения динамических
систем, то есть в некоторых случаях удается подобрать второй каскад таким образом,
что прямое произведение будет обладать энергетической функцией. Ключевые слова: прямое произведение, диффеоморфизм, цепно рекуррентное мно-
жество, энергетическая функция Для
цитирования:
Баринова
М. К.,
Шустова
Е. К. Об
энергетической
функ-
ции
для
прямого
произведения
дискретных
динамических
систем
//
Жур-
нал
Средневолжского
математического
общества. 2023. Т. 25,
№
2. С. 11–21. DOI: https://doi.org/10.15507/2079-6900.25.202302.11-21 Информация об авторах: ф р
ц
р
Баринова Марина Константиновна, старший научный сотрудник международ-
ной лаборатории динамических систем и приложений, Национальный исследователь-
ский университет «Высшая школа экономики» (603150, Россия, г. Нижний Новго-
род, ул. Большая Печерская, д. 25/12), ORCID: https://orcid.org/0000-0002-4406-583X,
mkbarinova@yandex.ru ф
ц
Баринова Марина Константиновна, старший научный сотрудник международ-
ной лаборатории динамических систем и приложений, Национальный исследователь-
ский университет «Высшая школа экономики» (603150, Россия, г. Нижний Новго-
род, ул. Большая Печерская, д. 25/12), ORCID: https://orcid.org/0000-0002-4406-583X,
mkbarinova@yandex.ru Шустова Евгения Константиновна, студент, Национальный исследовательский
университет «Высшая школа экономики» (603150, Россия, г. Нижний Новгород,
ул. Большая
Печерская, д. 25/12),
ORCID: https://orcid.org/0000-0002-4998-2186,
ekshustova@gmail.com Zhurnal Srednevolzhskogo Matematicheskogo Obshchestva. 2023. Vol. 25, No. 2. 12 Original article Original article MSC2020 37D20 MSC2020 37D20 Energy Function for Direct Products of Discrete
Dynamical Systems M. K. Barinova, E. K. Shustova HSE University (Nizhny Novgorod, Russian Federation) 1ε-цепью длины n, соединяющей точку x с точкой y для каскада f : M →M называется последо-
вательность x = x0, . . . , xn = y точек в M такая, что d(f(xi−1), xi) < ε для 1 ⩽i ⩽n. Точка x ∈M
называется цепно рекуррентной для каскада f, если для любого ε > 0 существует n, зависящее от ε,
и ε-цепь длины n, соединяющая точку x c ней самой. На множестве Rf можно ввести отношение эк-
вивалентности ∼следующим образом: x ∼y тогда и только тогда, когда для любого ε > 0 существует
ε-цепь, соединяющая точку x c точкой y, и ε-цепь, соединяющая точку y c точкой x. Две такие точки
называются цепно эквивалентными, класс эквивалентности называется цепной компонентой, множе-
ство всех цепно рекуррентных точек называется цепно-рекуррентным множеством и обозначается
Rf .
2 1.
Введение Хорошо известно, что дискретные динамические системы, в отличие от непрерыв-
ных, не всегда обладают энергетической функцией – гладкой функцией Ляпунова, мно-
жество критических точек которой совпадает с цепно-рекуррентным множеством ди-
намической системы. На сегодняшний день критерий существования такой функции не
известен. Еще в 1977 г. Д. Пикстон построил пример диффеоморфизма Морса-Смейла,
не обладающего энергетической функцией. Позднее был найден класс каскадов с хао-
тической гиперболической динамикой, у которых нет энергетической функции. Пусть M — гладкое n-многообразие и f : M →M — диффеоморфизм с цепно-
рекуррентным1 множеством Rf. Функцией Ляпунова [1] для каскада f : M →M на-
зывается непрерывная функция ϕ : M →R, обладающая следующими свойствами: M. K. Barinova, E. K. Shustova. Energy function for direct products of discrete dynamical systems Журнал Средневолжского математического общества. 2023. Т. 25, №2. 13 1) если x /∈Rf, то ϕ(x) > ϕ(f(x)), т. е. функция Ляпунова убывает вдоль орбит вне
цепно-рекуррентного множества; 1) если x /∈Rf, то ϕ(x) > ϕ(f(x)), т. е. функция Ляпунова убывает вдоль орбит вне
цепно-рекуррентного множества; 2) если x, y ∈Rf, то ϕ(x) = ϕ(y) тогда и только тогда, когда x ∼y; р
д
фу
ц
ϕ
,
ϕ( )
3Структурная устойчивость ограничений систем на неблуждающие множества называется Ω-
устойчивостью. f
2Точка x ∈M называется критической для функции ϕ : M →R, если ∇ϕ(x) = 0.
3 М. К. Баринова, Е. К. Шустова . Об энергетической функции для прямого произведения . . . f
2Точка x ∈M называется критической для функции ϕ : M →R, если ∇ϕ(x) = 0.
3Структурная устойчивость ограничений систем на неблуждающие множества называется Ω-
устойчивостью. 3) ϕ(Rf) — нигде не плотное подмножество R. 3) ϕ(Rf) — нигде не плотное подмножество R. В силу результатов Ч. Конли [1] такая функция существует для любой динамиче-
ской системы, а сам факт существования носит название «Фундаментальная теорема
динамических систем». Гладкая функция Ляпунова, множество критических точек2
которой совпадает с цепно рекуррентным множеством системы, называется энергети-
ческой функцией [2] . Вопросом существования энергетических функций занимались К. Мейер [2],
С. Смейл [3], Дж. Фрэнкс [4], M. Шуб [5], Ф. Такенс [6]. На настоящий момент из-
вестно, что энергетическая функция есть у любого потока, заданного на замкнутой
поверхности ([4]). Для дискретных динамических систем выделено несколько классов
каскадов, обладающих энергетической функцией, как с регулярной динамикой, так и
с хаотической [7–9]. Также были найдены классы диффеоморфизмов, у которых не су-
ществует энергетических функций [10–11]. Более подробную информацию по данной
тематике можно найти в обзоре [12]. Пусть M = M1 ×M2, где M1 и M2 — гладкие многообразия. Тогда диффеоморфизм
f : M →M называется прямым произведением диффеоморфизмов f1 : M1 →M1
и f2 : M2 →M2 и обозначается f = f1 × f2, если f(x1, x2) = (f1(x1), f2(x2)), где xi ∈
∈Mi. Многие свойства динамических систем переносятся на их прямые произведения,
например, если диффеоморфизмы f1 и f2 структурно устойчивые или Ω-устойчивые3,
то и f является таковым [13]. Также, если каскады f1 и f2 обладают энергетическими
функциями и хотя бы у одного из них конечное число цепных компонент, то и у f есть
энергетическая функция. Рассмотрим прямое произведение структурно устойчивого диффеоморфизма f1 :
T2 →T2, заданного на двумерном торе T2, неблуждающее множество которого содер-
жит нульмерное нетривиальное базисное множество без пар сопряженных точек (более
подробное описание диффеоморфизма f1 будет дано в разделе 2.), и тождественного
диффеоморфизма f2 = Id : R →R. Из работы [11] следует факт отсутствия энергетиче-
ской функции у диффеоморфизма f1, а энергетическая функция для диффеоморфизма
f2 — константа на R. Таким образом, сформулируем следующую теорему. Т е о р е м а
1.1. Пусть f1 — структурно устойчивый диффеоморфизм дву-
мерного тора, неблуждающее множество которого состоит из источника, стока и
нульмерного базисного множества без пар сопряженных точек. Тогда существует аринова, Е. К. Шустова . Об энергетической функции для прямого произведения . . . Zhurnal Srednevolzhskogo Matematicheskogo Obshchestva. 2023. Vol. 25, No. 2. 14 диффеоморфизм f2 такой, что прямое произведение f1 × f2 обладает энергетической
функцией. диффеоморфизм f2 такой, что прямое произведение f1 × f2 обладает энергетической
функцией. Журнал Средневолжского математического общества. 2023. Т. 25, №2. Журнал Средневолжского математического общества. 2023. Т. 25, №2. 15 В силу фундаментальной теоремы динамических систем Ч. Конли данная система
обладает функцией Ляпунова. Однако в работе [11] было доказано, что f1 не обладает
энергетической функцией, т. е. множество критических точек любой функции Ляпуно-
ва для данного диффеоморфизма не совпадает с цепно-рекуррентным множеством. 3.
Построение энергетической функции Рассмотрим прямое произведение диффеоморфизма f1 : T2 →T2 на тождественный
диффеоморфизм f2 = Id : R →R. В данном разделе мы построим энергетическую
функцию для диффеоморфизма f = f1 × f2 : M →M, где M = T2 × R. Для удобства
мы будем использовать в качестве обозначения точки на многообразии M либо символ
a, либо (t, z), подразумевая, что a = (t, z), a ∈M, t ∈T2, z ∈R. Напомним, что цепно-рекуррентное множество диффеоморфизма f1 состоит из ис-
точника α, стока ω и нульмерного седлового множества Σ, а у диффеоморфизма f2
всего одна цепная компонента, совпадающая с R. Тогда цепные компоненты прямого
произведения f = f1 × f2 — это α × R, ω × R и Σ × R, обозначим их через Rα, Rω и RΣ
соответственно. Положим также W s
Rα = W s
α × R, W s
Rω = W s
ω × R и W s
RΣ = W s
Σ × R. α
ω
Σ
Построение энергетической функции разобьем на 3 шага. 2.
Диффеоморфизм с нульмерным базисным множеством В данном разделе мы опишем пример диффеоморфизма с нульмерным нетривиаль-
ным базисным множеством без пар сопряженных точек и приведем некоторые свойства
таких диффеоморфизмов. Рассмотрим диффеоморфизм Аносова fA : T2 →T2, индуцированный линейным
отображением плоскости LA : R2 →R2, заданным с помощью гиперболической матри-
цы A ∈GL(2, Z) с собственными значениями λ и 1/λ, где λ > 1. Выберем две различные неподвижные точки p и q диффеоморфизма fA (если fA не
имеет двух неподвижных точек, достаточно рассмотреть в качестве матрицы A некото-
рую ее степень). Чтобы получить диффеоморфизм f1 с нульмерным седловым базис-
ным множеством, проведем «хирургические операции Смейла» [3] в непересекающихся
окрестностях Up и Uq неподвижных точек p и q таким образом, чтобы в результате в
Up получился гиперболический источник α, а в Uq — гиперболический сток ω. Кроме α
и ω цепно-рекуррентное множество диффеоморфизма f1 будет содержать нульмерное
седловое множество Σ без пар сопряженных точек4. Множество Σ при этом будет иметь
локальную структуру прямого произведения канторовского множества на самого себя
(см. рис. 2.1). α
ω
Рис. 2.1. Диффеоморфизм с нульмерным нетривиальным базисным
множеством Рис. 2.1. Диффеоморфизм с нульмерным нетривиальным базисным
множеством Fig. 2.1. Diffeomorphism with a zero-dimensional nontrivial basic set Fig. 2.1. Diffeomorphism with a zero-dimensional nontrivial basic set Каскады с такой динамикой изучались в работе [8]. Приведем некоторые свойства
диффеоморфизма f1. При таком построении цепно-рекуррентное множество Rf явля-
ется гиперболическим. Более того, диффеоморфизм f1 будет структурно устойчивым
[12]. Для каждой точки x ∈T2 можно определить устойчивое и неустойчивое многооб-
разия W s
x и W u
x следующим образом: W s
x = {y ∈T2 |
lim
n→+∞d(f n(x), f n(y)) = 0},
W u
x = {y ∈T2 |
lim
n→+∞d(f −n(x), f −n(y)) = 0}. Из теоремы о спектральном разложении [14] следует, что T2 = W u
α ∪W
u
Σ = W s
ω ∪W
s
Σ. 4Различные точки x, y ∈Λ называются парой сопряженных точек, если (x, y) ∈(W s
x ∩W u
y ), (x,
= ∅и (x, y)u∩∩Λ = ∅, где Λ – базисные множества. M. K. Barinova, E. K. Shustova. Energy function for direct products of discrete dynamical systems М. К. Баринова, Е. К. Шустова . Об энергетической функции для прямого произведения . . Сначала построим гладкую функцию Φ : M →[0, 1] со следующими свойствами: Сначала построим гладкую функцию Φ : M →[0, 1] со следующими свойствами: 1) Φ|W u
Rα является энергетической функцией для ограничения диффеоморфизма f
на W u
Rα; 2) Φ(a) = 1 для всех a ∈Rα;
3) Φ(a) = 0 для всех a ∈W
u
RΣ. 2) Φ(a) = 1 для всех a ∈Rα; 2) Φ(a) = 1 для всех a ∈Rα; 3) Φ(a) = 0 для всех a ∈W
u
RΣ. 4) Функция Φ(a) не зависит от z, где a = (t, z), t ∈T2, z ∈R. Пусть hα : W u
α →R2 — диффеоморфизм, сопрягающий f1|W u
α с линейным растяже-
нием плоскости Lα : R2 →R2, L(x, y) = (λx, λy), то есть hα ◦f = Lα ◦hα. 2 Пусть hα : W u
α →R2 — диффеоморфизм, сопрягающий f1|W u
α с линейным растяже-
нием плоскости Lα : R2 →R2, L(x, y) = (λx, λy), то есть hα ◦f = Lα ◦hα. Функция ϕLα : R2 →[0, 1], определенная формулой (
)
(
)
Функция ϕLα : R2 →[0, 1], определенная формулой ϕLα(x, y) =
1 −x2 −y2,
x2 + y2 ⩽1/4,
3
4e(1−4x2−4y2)/3,
x2 + y2 > 1/4, является энергетической функцией для диффеоморфизма Lα. Тогда функция ϕcont :
T2 →[0, 1] ϕcont(t) =
(
ϕLα ◦hα,
t ∈W u
α,
0,
иначе, иначе, будет энергетической функцией для f1|W u
α и непрерывной на всём T2. По [8, Лемма 5]
существует функция uα : [0, 1] →[0, 1] такая, что ϕ = uα ◦ϕcont — энергетическая
функция для f1|W u
α , но уже гладкая на всём T2 (см. рисунок 3.1). М. К. Баринова, Е. К. Шустова . Об энергетической функции для прямого произведения . . . М. К. Баринова, Е. К. Шустова . Об энергетической функции для прямого произведения . . . Zhurnal Srednevolzhskogo Matematicheskogo Obshchestva. 2023. Vol. 25, No. 2. 16 α
ω
Рис. 3.1. График функции ϕ : T2 →[0, 1]
Fig. 3.1. Function ϕ : T2 →[0, 1] Рис. 3.1. График функции ϕ : T2 →[0, 1]
Fig. 3.1. Function ϕ : T2 →[0, 1] Тогда функция Φ(t, z) = ϕ(t) для всех t ∈T2 и z ∈R — искомая. Построим гладкую функцию Ψ : M →[0, 1] со следующими свойствами 1) Ψ|W s
Rω — энергетическая функция для f|W s
Rω ; 1) Ψ|W s
Rω — энергетическая функция для f|W s
Rω ; 2) Ψ(a) = 0 для всех a ∈Rω; 2) Ψ(a) = 0 для всех a ∈Rω; 3) Ψ(a) = 1 для всех a ∈W
s
RΣ; 3) Ψ(a) = 1 для всех a ∈W
s
RΣ; 3) Ψ(a) = 1 для всех a ∈W
s
RΣ; 4) Ψ′
z(t, z) ̸= 0 для всех (t, z) ∈W s
Rω \ Rω. 4) Ψ′
z(t, z) ̸= 0 для всех (t, z) ∈W s
Rω \ Rω. 4) Ψ′
z(t, z) ̸= 0 для всех (t, z) ∈W s
Rω \ Rω. Пусть hshift : W s
Rω \ Rω →S1 × R × R = S1 × R2 — диффеоморфизм, такой что
hshift ◦(f1 × f2) = (Lshift × f2) ◦hshift, где Lshift : (s, x) →(s, x −1) для всех s ∈S1 и
x ∈R. Рассмотрим расслоение R2 на кривые вида lc = {(x, y) ∈R2 | x ∈(c−1, c+ 1), y = {(
)
|
(
)
= tg π(x −c)
2
} и функцию ψ : S1 × R2 →[0, 1], определенную формулой ψ(s, x, y) =
1
1
S1 (
)
l (
Р
3 2) = tg π(x −c)
2
} и функцию ψ : S1 × R2 →[0, 1], определенную формулой ψ(s,
1
1 = tg π(x −c)
2
} и функцию ψ : S1 × R2 →[0, 1], определенную формулой ψ(s, x, y) =
= 1
2 + 1
π arctg c, s ∈S1, (x, y) ∈lc (см. Рис. 3.2). = 1
2 + 1
π arctg c, s ∈S1, (x, y) ∈lc (см. Рис. 3.2). = 1
2 + 1
π arctg c, s ∈S1, (x, y) ∈lc (см. Рис. 3.2). 2
π
Непосредственно проверяется, что функция ψ — энергетическая для диффеомор-
физма Lshift × f2. Тогда функция ψcont : M →[0, 1] ψcont(a) =
ψ ◦hshift,
a ∈W s
Rω \ Rω,
0,
a ∈Rω,
1,
иначе будет энергетической функцией для f|W s
Rω и непрерывной на M. Действительно, мно-
жество W s
Rω содержит единственную цепную компоненту Rω и Ψ(a) = 0 для всех
a ∈Rω. Теперь покажем убывание вдоль траектории вне цепно рекуррентного мно-
жества, т. е. если a /∈Rω, то ψcont(a) > ψcont(f(a)). 3.2.
Шаг 2 Построим гладкую функцию Ψ : M →[0, 1] со следующими свойствами: Построим гладкую функцию Ψ : M →[0, 1] со следующими свойствами: Построим гладкую функцию Ψ : M →[0, 1] со следующими свойствами: 1) Ψ|W s
Rω — энергетическая функция для f|W s
Rω ; Curve lines of the fuction ψ : S1 × R2 →[0, 1] in the set R3 \ Oz if the
point (s, x, y) ∈S1 × R2 corresponds to the point (λx, 2πs, y) ∈R3 \ Oz in
cylindrical coordinates Fig. 3.2. Curve lines of the fuction ψ : S1 × R2 →[0, 1] in the set R3 \ Oz if the
point (s, x, y) ∈S1 × R2 corresponds to the point (λx, 2πs, y) ∈R3 \ Oz in
cylindrical coordinates Таким образом, функция ψcont|W s
Rω убывает вдоль траекторий вне цепно рекуррент-
ного множества диффеоморфизма f|W s
Rω . Таким образом, функция ψcont|W s
Rω убывает вдоль траекторий вне цепно рекуррент-
ного множества диффеоморфизма f|W s
Rω . ω
Из [8] следует, что существует функция uω : [0, 1] →[0, 1], такая что Ψ = uω ◦ψcont
будет энергетической функцией для f|W s
Rω и гладкой на M. Заметим, что uω′(x) = 0 то-
гда и только тогда, когда x ∈{0, 1}. Для того, чтобы Ψ оказалась искомой, необходимо
проверить выполнение пункта 4, т. е. то, что Ψ′
z(t, z) ̸= 0 для всех (t, z) ∈W s
Rω \ Rω. Ψ′
z(t, z) = (uω ◦ψcont(t, z))′
z = uω′ψcont′
z(t, z) = uω′ψ′
y(s, x, y) = uω′(1
2 + 1
π arctg(x −
2
π arctg(y)))′
y = uω′ 1
π ·
1
1 + (x −2
π arctg(y))2
·(−2
π )·
1
1 + y2 ̸= 0 для всех (t, z) ∈W s
Rω \Rω. Ψ′
z(t, z) = (uω ◦ψcont(t, z))′
z = uω′ψcont′
z(t, z) = uω′ψ′
y(s, x, y) = uω′(1
2 + 1
π arctg(x −
2
π arctg(y)))′
y = uω′ 1
π ·
1
1 + (x −2
π arctg(y))2
·(−2
π )·
1
1 + y2 ̸= 0 для всех (t, z) ∈W s
Rω \Rω. 3.3. Шаг 3 1) Ψ|W s
Rω — энергетическая функция для f|W s
Rω ; • ψcont(a) = ψ(hshift(a)) = ψ(s, x, y), где hshift(a) = (s, x, y); • ψcont(f(a))
=
ψcont(hshift(f(a)))
=
ψ((Lshift × f2)(hshift(a)))
=
ψ((Lshift×
×f2)(s, x, y)) = ψ(Lshift(s, x), f2(y)) = ψ(s, x −1, y); • ψcont(f(a))
=
ψcont(hshift(f(a)))
=
ψ((Lshift × f2)(hshift(a)))
=
ψ((Lshift×
×f2)(s, x, y)) = ψ(Lshift(s, x), f2(y)) = ψ(s, x −1, y); • ψ(s, x, y) > ψ(s, x −1, y), т. к. ψ(s, x, y) = 1
2 + 1
π arctg c1, где c1 = x −2
π arctg y, и
ψ(s, x −1, y) = 1
2 + 1
π arctg c2, где c2 = x −1 −2
π arctg y. Отсюда c1 > c2. ψ(s, x, y) > ψ(s, x −1, y), т. к. ψ(s, x, y) = 1
2 + 1
π arctg c1, где c1 = x −2
π arctg y,
ψ(s, x −1, y) = 1
2 + 1
π arctg c2, где c2 = x −1 −2
π arctg y. Отсюда c1 > c2. • ψ(s, x, y) > ψ(s, x −1, y), т. к. ψ(s, x, y) = 1
2 + 1
π arctg c1, где c1 = x −2
π arctg y, и
ψ(s, x −1, y) = 1
2 + 1
π arctg c2, где c2 = x −1 −2
π arctg y. Отсюда c1 > c2. M. K. Barinova, E. K. Shustova. Energy function for direct products of discrete dynamical systems M. K. Barinova, E. K. Shustova. Energy function for direct products of discrete dynamical systems Shustova. Energy function for direct products of discrete dynamical systems Журнал Средневолжского математического общества. 2023. Т. 25, №2. 17 ω
Рис. 3.2. Линии уровня функции ψ : S1 × R2 →[0, 1] в множестве R3 \ Oz, если
точка (s, x, y) ∈S1 × R2 соответствует точке (λx, 2πs, y) ∈R3 \ Oz
в цилиндрических координатах
Fig. 3.2. Curve lines of the fuction ψ : S1 × R2 →[0, 1] in the set R3 \ Oz if the
point (s, x, y) ∈S1 × R2 corresponds to the point (λx, 2πs, y) ∈R3 \ Oz in
cylindrical coordinates Рис. 3.2. Линии уровня функции ψ : S1 × R2 →[0, 1] в множестве R3 \ Oz, если
точка (s, x, y) ∈S1 × R2 соответствует точке (λx, 2πs, y) ∈R3 \ Oz (
в цилиндрических координатах Fig. 3.2. 1) Θ — функция Ляпунова для f; 3.3.
Шаг 3 Пусть
теперь (t, z) /∈Rf. Тогда может быть один из трех вариантов: • (t, z) ∈BRα\BRω, тогда grad Φ(t, z) ̸= 0, grad Ψ(t, z) = 0, а значит, grad Θ(t, z) ̸= 0;
• (t, z) ∈BRω\BRα, тогда grad Φ(t, z) = 0, grad Ψ(t, z) ̸= 0, а значит, grad Θ(t, z) ̸= 0; • (t, z) ∈BRα\BRω, тогда grad Φ(t, z) ̸= 0, grad Ψ(t, z) = 0, а значит, grad Θ(t, z) ̸= 0;
• (t, z) ∈BRω\BRα, тогда grad Φ(t, z) = 0, grad Ψ(t, z) ̸= 0, а значит, grad Θ(t, z) ̸= 0;
• (t, z) ∈BRω ∩BRα, тогда Φ′
z(t, z) = 0, Ψ′
z ̸= 0, а значит, grad Θ(t, z) ̸= 0. • (t, z) ∈BRω ∩BRα, тогда Φ′
z(t, z) = 0, Ψ′
z ̸= 0, а значит, grad Θ(t, z) ̸= 0. Таким образом, Θ — энергетическая функция для диффеоморфизма f. Таким образом, Θ — энергетическая функция для диффеоморфизма f. 4.
Заключительные замечания Энергетическую функцию в данном примере удается построить за счет того, что
цепно-рекуррентное множество для тождественного диффеоморфизма — это вся дей-
ствительная прямая. В действительности вместо f2 можно использовать любой диф-
феоморфизм с таким свойством, например, f2(x) = −x. Возникает вопрос, какими
свойствами должен обладать диффеоморфизм f2, чтобы для прямого произведения
f1 ×f2 не существовало энергетической функции, при условии, что диффеоморфизм f1
ее не имеет. Имеет место следующая гипотеза: диффеоморфизм f2 должен иметь хотя
бы одну компактную цепную компоненту. Благодарности. Исследование динамики диффеоморфизмов рассматриваемого
класса поддержано грантом РНФ (проект 21-11-00010). 3.3.
Шаг 3 Докажем, что функция Θ = Φ + Ψ — энергетическая для диффеоморфизма f. Для
этого проверим выполнение следующих условий: 1) Θ — функция Ляпунова для f; 2) Θ — гладкая; М. К. Баринова, Е. К. Шустова . Об энергетической функции для прямого произведения . . . Zhurnal Srednevolzhskogo Matematicheskogo Obshchestva. 2023. Vol. 25, No. 2. 18 3) Множество критических точек Cr(Θ) совпадает с цепно-рекуррентным множе-
ством диффеоморфизма f × g. Напомним, что цепно рекуррентное множество Rf диффеоморфизма f состоит из
из трех цепных компонент Rω, Rα и RΣ. Для удобства будем использовать следующие
обозначения: BRω = W s
Rω \Rω, BRα = W u
Rα \Rα. Тогда M = Rα ⊔Rω ⊔RΣ ⊔(BRα ∪BRω). Заметим, что BRα ∩BRω ̸= ∅. 1. Докажем сначала убывание вдоль траекторий вне цепно рекуррентного множе-
ства. Если a /∈Rf, то либо a ∈BRω, либо a ∈BRα. В первом случае Φ(a) ⩾Φ(f(a)),
а Ψ(a) > Ψ(f(a)). Во втором случае Φ(a) > Φ(f(a)), а Ψ(a) ⩾Ψ(f(a)). Таким образом,
если a /∈Rf, то Θ(a) > Θ(f(a)). 1. Докажем сначала убывание вдоль траекторий вне цепно рекуррентного множе-
ства. Если a /∈Rf, то либо a ∈BRω, либо a ∈BRα. В первом случае Φ(a) ⩾Φ(f(a)),
а Ψ(a) > Ψ(f(a)). Во втором случае Φ(a) > Φ(f(a)), а Ψ(a) ⩾Ψ(f(a)). Таким образом,
если a /∈Rf, то Θ(a) > Θ(f(a)). /
f
( )
( ( ))
Заметим, что по построению Θ(Rω) = 0, Θ(Rα) = 2 и Θ(RΣ) = 1. 2. Функция Θ – гладкая как линейная комбинация гладких функций. 3. Покажем, что градиент функции Θ обращается в ноль только в цепно-
рекуррентных точках. 3. Покажем, что градиент функции Θ обращается в ноль только в цепно-
рекуррентных точках. По построению, функция Φ(t, z) = ϕ(t), где t ∈T2, т. е. она не зависит от координаты
z и Φ(t, z)′
z = 0 для любого z ∈R, а значит, ее градиент имеет вид: grad Φ(t, z) =
(grad ϕ(t), 0), где grad ϕ(t) ̸= 0 тогда и только тогда, когда t ∈W u
α \ α, а значит,
grad Φ(t, z) ̸= 0 тогда и только тогда, когда (t, z) ∈BRα. Конструкция функции Ψ(t, z)
такова, что grad Ψ(t, z) ̸= 0 и Ψ′
z(t, z) ̸= 0 тогда и только тогда, когда (t, z) ∈BRω. g
(
) ̸
z(
) ̸
(
)
ω
Очевидно, что если (t, z) ∈Rf, то grad Θ(t, z) = grad Φ(t, z)+grad Ψ(t, z) = 0. M. K. Barinova, E. K. Shustova. Energy function for direct products of discrete dynamical systems Список литературы 20 20 Поступила 27.01.2023; доработана после рецензирования 04.03.2023;
принята к публикации 25.05.2023 Поступила 27.01.2023; доработана после рецензирования 04.03.2023;
принята к публикации 25.05.2023 Авторы прочитали и одобрили окончательный вариант рукописи. Конфликт интересов: авторы заявляют об отсутствии конфликта интересов. Авторы прочитали и одобрили окончательный вариант рукописи. К
ф
б
ф Авторы прочитали и одобрили окончательный вариант рукописи. Конфликт интересов: авторы заявляют об отсутствии конфликта интересов. Список литературы 1. Conley C. Isolated invariant sets and Morse index. Colorado: Am. Math. Soc., 1978. 89 p. Журнал Средневолжского математического общества. 2023. Т. 25, №2. 19 2. Meyer K. R. Energy functions for Morse–Smale systems // Amer. J. Math. 1968. Vol. 90, No. 4. pp. 1031–1040. DOI: https://doi.org/10.2307/2373287 3. Smale S. On gradient dynamical systems // Annals Math. 1961. Vol. 74, No. 1. pp. 199–206. DOI: https://doi.org/10.2307/1970311 4. Franks J. Nonsingular Smale flow on S3 // Topology. 1985. Vol. 24, No. 3. pp. 265–282. DOI: https://doi.org/10.1016/0040-9383(85)90002-3 5. Shub M. Morse-Smale diffeomorphism are unipotent on homology // Dynamical
Systems. 1973. pp. 489–491. DOI: https://doi.org/10.1016/B978-0-12-550350-1. 50040-0 6. Takens F. Tolerance stability // Dynamical systems -Warwick 1974 (Proc. Sympos. Appl. Topology and Dynamical Systems, Univ. Warwick, Coventry, 1973/1974;
presented to E. C. Zeeman on his fiftieth birthday), Lecture Notes in Math., vol. 468,
Springer, 1975, p. 293-304. 7. Grines
V. Z.,
Laudenbach
F.,
Pochinka
O. V. Dynamically
ordered
energy
function
for
Morse-Smale
diffeomorphisms
on
3-manifolds
//
Proceedings
of
the
Steklov
Institute
of
Mathematics. 2012. Vol. 278. pp. 34–48. DOI:
https://doi.org/10.1134/S0081543812060041 8. Barinova M., Grines V., Pochinka O., Yu B. Existence of an energy function for
three-dimensional chaotic “sink-source” cascades // Chaos. 2021. Vol. 31, No. 6. DOI:
https://doi.org/10.1063/5.0026293 9. Гринес В. З., Носкова М. К., Починка О. В. Построение энергетической функ-
ции для A-диффеоморфизмов с двумерным неблуждающим множеством на 3-
многообразиях // Журнал Средневолжского математического общества. 2015. Vol. 17, No. 3. pp. 12–17. 10. Pixton D. Wild unstable manifolds// Topology. 1977. Vol. 16, No. 2. pp. 167–172. DOI: https://doi.org/10.1016/0040-9383(77)90014-3 11. Barinova M. On existence of an energy function for ω-stable surface diffeomorphisms
// Lobachevskii Journal of Mathematics. 2021. Vol. 42, No. 14. pp. 3317–3323. DOI:
https://doi.org/10.1134/S1995080222020020 12. Гринес В. З., Починка О. В. Построение энергетических функций для омега-
устойчивых диффеоморфизмов на 2- и 3-многообразиях // Современная ма-
тематика. Фундаментальные направления. 2017. Т. 63, №2. С. 191–222. DOI:
https://doi.org/10.22363/2413-3639-2017-63-2-191-222 13. Баринова М. К., Шустова Е. К. Динамичекие свойства прямых произведений
дискретных динамических систем // Журнал Средневолжского математическо-
го общества. 2022. Т. 24, №1. С. 21–30. DOI: https://doi.org/10.15507/2079-
6900.24.202201.21-30 14. Смейл С. Дифференцируемые динамические системы // Успехи мат. наук. 1970. Т. 25, №1. pp. 113–185. М. К. Баринова, Е. К. Шустова . Об энергетической функции для прямого произведения . . Zhurnal Srednevolzhskogo Matematicheskogo Obshchestva. 2023. Vol. 25, No. 2. М. К. Баринова, Е. К. Шустова . Об энергетической функции для прямого произведения . . . References 1. C. Conley, “Isolated invariant sets and Morse index”, 1978, 89 p. 2. K. Meyer, “Energy functions for Morse–Smale systems”, Amer. J. Math, 90:4 (1968),
1031—1040. DOI: https://doi.org/10.2307/2373287 3. S. Smale, “On gradient dynamical systems”, Annals Math, 74:1 (1961), 199—206. DOI:
https://doi.org/10.2307/1970311 4. J. Franks, “Nonsingular Smale flow on S3”, Topology, 24:3 (1985), 265—282. DOI:
https://doi.org/10.1016/0040-9383(85)90002-3 5. M. Shub, “Morse-Smale diffeomorphism are unipotent on homology”, Dynamical Sys-
tems, 1973, 489-491. DOI: https://doi.org/10.1016/B978-0-12-550350-1.50040-0 6. F. Takens, “Tolerance stability”, Dynamical systems -Warwick 1974 (Proc. Sympos. Appl. Topology and Dynamical Systems, Univ. Warwick, Coventry, 1973/1974; pre-
sented to E. C. Zeeman on his fiftieth birthday, Lecture Notes in Math., vol. 468,
Springer, 1975), 1974, 293-304. 7. V. Z. Grines, F. Laudenbach, O. V. Pochinka, “Dynamically ordered energy function
for Morse-Smale diffeomorphisms on 3-manifolds”, Proceedings of the Steklov Institute
of Mathematics, 278 (2012), 27–40. DOI: https://doi.org/10.1134/S0081543812060041 8. M. Barinova, V. Grines, O. Pochinka, B. Yu, “Existence of an energy function
for three-dimensional chaotic “sink-source” cascades jour Chaos”, 31:6 (2021). DOI:
https://doi.org/10.1063/5.0026293 9. V. Z. Grines, M. K. Noskova, O. V. Pochinka, “Construction of an energy function for
A-diffeomorphisms of two-dimensional non-wandering sets on 3-manifolds”, Zhurnal
SVMO, 17:3 (2015), 12–17. 10. D. Pixton, “Wild unstable manifolds”, Topology, 16:2 (1977), 167—172. DOI:
https://doi.org/10.1016/0040-9383(77)90014-3 11. M. Barinova, “On existence of an energy function for ω-stable surface Diffeomor-
phisms”, Lobachevskii Journal of Mathematics, 42:14 (. 2021), 3317–3323. DOI:
https://doi.org/10.1134/S1995080222020020 12. V. Grines, O. Pochinka, “Constructing energy function for certain classes of omega-
stable and diffeomorphisms on manifolds od dimention 2 and 3”, Journal of Mathemat-
ical Sciences, 63:2 (2017), 191–222 (In Russ.). DOI: https://doi.org/10.22363/2413-
3639-2017-63-2-191-222 M. K. Barinova, E. K. Shustova. Energy function for direct products of discrete dynamical systems Журнал Средневолжского математического общества. 2023. Т. 25, №2. 21 13. M. K. Barinova, E. K. Shustova, “Dynamical properties of direct products of dis-
crete dynamical systems”, Zhurnal SVMO, 24:1 (2022), 21-30
(In Russ.). DOI:
https://doi.org/10.15507/2079-6900.24.202201.21-30 13. M. K. Barinova, E. K. Shustova, “Dynamical properties of direct products of dis-
crete dynamical systems”, Zhurnal SVMO, 24:1 (2022), 21-30
(In Russ.). DOI:
https://doi.org/10.15507/2079-6900.24.202201.21-30 14. S. Smale, “Differentiable dynamical systems”, Russian Mathematical Surveys, 25:1
(1970), 113–185 (In Russ.). 14. S. Smale, “Differentiable dynamical systems”, Russian Mathematical Surveys, 25:1
(1970), 113–185 (In Russ.). Submitted 27.01.2023; Revised 04.03.2023; Accepted 25.05.2023 Submitted 27.01.2023; Revised 04.03.2023; Accepted 25.05.2023 Conflict of interest: The authors declare no conflict of interest. Submitted 27.01.2023; Revised 04.03.2023; Accepted 25.05.2023 The authors have read and approved the final manuscript.
|
https://openalex.org/W1996280654
|
https://zenodo.org/records/1820642/files/article.pdf
|
English
| null |
Mote and Bretesche Building in Ireland
|
English historical review
| 1,906
|
public-domain
| 18,443
|
NO. LXXXIII.—JULY 1906* NO. LXXXIII.—JULY 1906* L THE BRETESCHE. A
NEW light upon the nature of the first fortresses built by the
Normans in Ireland may, I think, be gained from a consider-
ation of the number and distribution of certain Irish place names
involving one or other of the terms mote and breteache. The
mote names, indeed, are so obvious that they have not been alto-
gether overlooked, but their significance has, I think, been missed,
while even the existence of the bretesche names has not hitherto
been suspected. A
i To take the latter, as the more important for our argument,
first: The word Brittas, sometimes slightly modified, constitutes or
'fonnB part of the names of thirty-seven townlands in Ireland. From the form of the name and from the distribution and posi-
tions of the townlands I think it may be shown that the word
' Brittas' is not of Irish origin at all, but represents the Old French
breUtcke, or rather, more immediately, an AHglo-Norman or a
Middle-EngliBh form of that word. From all the available data it
may be inferred that the term was used in Ireland in early Anglo-
Norman times to denote a complete fortress, consisting of a wooden
tower, often but not always placed on a mote, or mound of
earth, surrounded by a fosse and earthen rampart, and (as we may
suppose) further protected by a palisade ; that these towers we*e
erected by Anglo-Norman or English settlers in the twelfth and
early part of the thirteenth centuries; that though in some early
cases there is evidence that they were the principal fortresses K B VOL. XXI. NO. T.TTTTTT- * All rights reserved MOTE AND BRETESCHE 418 July erected on the feudal holdings, yet in general the positions of those
that have left their names on the townlands seem to indicate that
they were subsidiary to stone castles, and were placed on the
frontiers of districts occupied by the English to watch or guard
some pass or other probable line of approach of hostile Irish
tribes.1 Later in the thirteenth century, when castles were com-
monly built of stone and many of the earlier bretescb.es were re-
placed by stone castles, the name bretesche—in various forms—
came to be applied to wooden towers and crenelated parapets,
built as mere adjuncts to stone castles on the ramparts and else-
where. 1 Probably these subsidiary or frontier bretesehes partially indicate the result of
royal writs in the year 1200 and again in 1216, ordering all persons holding lands in
the marches to fortify their castles or lands under pain of confiscation (Calendar of
Documents relating to Ireland, ed. Sweetman, TOL i. nog. 125, 674. This Calendar is
hereinafter referred to as C.DJ.)
' Irish Names of Places, vol. ii. pp. 14, 389.
» O'Brien's Irish-Engl. Diet. -(1768) gives, ' Brit and Brtac signify speckled,
spotted, particoloured, or painted; hence Britineach and Briltxnniot, the Hazles
(measles), as being a speckled or painted distemper [unfortunately the word is
BruiUnech, Arehiv far celt. PhiL, connected with bruit, to become hot, boil], hence
also Briotnach or Breatnach, a Britton or Welshman, whence Brittania compounded
of Brit, painted, and ta'n or tain, an Irish or Celtic word meaning a country.'
This
last derivation is virtually taken from Camden and is quite worthless. Besides the
word apparently referred to, brith, painted, is Old Welsh, not Irish.
Dinneen's
Dictionary
gives Briotas as a topographical word only (probably taking it from
Joyce), and does not give brit or briot at alL O'Beilly does not give briotas, bnt gives
' speckled' aa one of the meanings of briot, taking the word from Shaw's
Dictionary
of Scottish Gaelic L THE BRETESCHE. This is the principal meaning of the term generally given
in our dictionaries, but the term in this sense has not, I think,
affected our place names. An Irish etymology of the name has indeed been suggested by
Dr. Joyce.1 I say ' suggested,' because his interpretation of the
word is really a guess, for the word iB not, I believe, supported by
any pre-Norman, or indeed any early, text. There is said to be a
word brit, meaning' speckled,' but even this word seems to rest on no
^ood evidence.1 Assuming, however, the adjective brit, ' speckled,'
the form brittas, ' a speckled place,' is only arrived at by analogy
to some other abstract nouns which are formed from adjectives by
the addition of -«. It is in itself, apart from these place names,
entirely unattested. But even assuming that there was an Irish
"word britas or briotas, meaning a speckled place, the form Bally-
brittas could hardly have arisen among a purely Irish-speaking
people. We should expect a genitive inflexion with or without the
article, and the Anglicised result would be BaUinvrittish, or Bally-
brittish, or something of that sort. Too much stress should not
be laid on this last point, as irregularities occur. It may, however,
be noted that the word brittas is not to be found in combination
with dun, liss, rath, moin, magh, drum, don, carrick, caher, or, so 1 Probably these subsidiary or frontier bretesehes partially indicate the result of
royal writs in the year 1200 and again in 1216, ordering all persons holding lands in
the marches to fortify their castles or lands under pain of confiscation (Calendar of
Documents relating to Ireland, ed. Sweetman, TOL i. nog. 125, 674. This Calendar is
hereinafter referred to as C.DJ.) » O'Brien's Irish-Engl. Diet. -(1768) gives, ' Brit and Brtac signify speckled,
spotted, particoloured, or painted; hence Britineach and Briltxnniot, the Hazles
(measles), as being a speckled or painted distemper [unfortunately the word is
BruiUnech, Arehiv far celt. PhiL, connected with bruit, to become hot, boil], hence
also Briotnach or Breatnach, a Britton or Welshman, whence Brittania compounded
of Brit, painted, and ta'n or tain, an Irish or Celtic word meaning a country.'
This
last derivation is virtually taken from Camden and is quite worthless. Besides the
word apparently referred to, brith, painted, is Old Welsh, not Irish. ' Irish Names of Places, vol. ii. pp. 14, 389. 4 Godefroy, Diet, de Vancienne Langite Francaise.
» Robert of Gloucester's Chronicle, R.S. 1. 11094 et seqq., Hearne's ed. p. 636.
• Diet, des Communes de France, Joanne, 1864. Bescherelle, in his Dictionnaire,
says, under ' Breteche,' Ac, ' Ce mot s'est conserve en France dans quelqnea lieux on
il y avait des forteresses, eomme a la Brestoche pres Nangis en Brie, qui est la mtme
chose qne la Bretesohe.' Cf. Godefroy. L THE BRETESCHE. Dinneen's
Dictionary
gives Briotas as a topographical word only (probably taking it from
Joyce), and does not give brit or briot at alL O'Beilly does not give briotas, bnt gives
' speckled' aa one of the meanings of briot, taking the word from Shaw's
Dictionary
of Scottish Gaelic BUILDING
IN IRELAND 419 1906 far as I can discover, with any of the common elements of place
names, except 60%. ,
p
That Brittas really represents the Old French bvctesche will appear
more clearly when the distribution of the name has been examined,
its earlier forms noted, and its identity shown, in one case with ' La
Bretasche ' and in another with the ' Bretaschia ' of thirteenth-
century records. Here we may note that the 0. F. bretesche took a
great many forms, amongst others breteske, bretaske, and britasche
The English forms are also very numerous, and are classified in
the New English Dictionary (s.v. ' Brattice') under three different
types. It is enough here to mention the Middle-English brutaske,
brytasqe, from the Old Northern French breteske, bretaske, bretesqu
' The early forms in bru- and bry-, apparently of English or Anglo-
French origin, are due perhaps to the obscurity of the first vowel.'
The only example before the fourteenth century given in the New
English Dictionary is from Robert of Gloucester, circa 1297. The
passage is— Atfce lasts hii aende
Al the brutaske withoute & the bragge brende,
Vor he was al of tre [wood]; & Sir Maci & his
Flowe in to the tour an hey, tho hii seye this,
& defendede horn vaste, the wale hii mi3te iwis.s Atfce lasts hii aende
Al the brutaske withoute & the bragge brende,
Vor he was al of tre [wood]; & Sir Maci & his
Flowe in to the tour an hey, tho hii seye this,
& defendede horn vaste, the wale hii mi3te iwis.s The brutaske is here opposed to the high tower, probably a
stone keep, and, like the bridge, was probably of wood and com-
bustible. But earlier in the century the name seems to have been
applied, in Ireland at any rate, to the whole fortress. 4 Godefroy, Diet, de Vancienne Langite Francaise. L THE BRETESCHE. The forms
above mentioned might, I think, have given rise to the name which
has gradually settled down into Brittas, but the comparative
uniformity of the present spelling of the townland names is due
to the system pursued by the Ordnance surveyors. In earlier
documents we often find the name spelled Brytace, Brettas, Brettys,
&c, and sometimes, very significantly, with the French or the
English article before the name. The military term has survived
in some place names in France in a similar way; thus ' La
Grande et Petite Breteche' at Tours, in ancient Touraine, ' La
Breteche ' in the commune of ' St. Nom la Breteche,' department of
Seine et Oise, ' la fordt' and ' le chateau de la Bretesche' in Loire
Inferieure.6 Further research would probably largely add to these
examples. AB to the time when these bretesches were erected we have E E 2 MOTE AND BRETESCHE 420 July some direct evidence. Henry II brought some wooden towers
(castella li/piea or bret-eschiae) over with him, and materials fo
building others.7 As there were no walled towns to besiege—Dublin,
Waterford, and Wexford were already in Strongbow's hands—these
would seem to have been for defence. At any rate there seems to
me no good reason to doubt that the fortresses built by Eichard
the Fleming at Slane and Hugh de Lacy at Trim, described in the
Song of Da-mot,* were of the ' mote and bretesche' typo, and the
natural inference, supported, I think, by lines 3202-8205, is that
the feoffees in general of Richard FitzGilbert and Hugh de Lacy
fortified their lands in a similar way. A remarkable entry in the ' Annals of Loch Ce,' under the year
1208, gives an indication of the nature of the first castle at Meelick,
on the Shannon, in the country of the O'Maddens. A hosting by William Burke, accompanied by the foreigners of
Htmster and Meath, into Connaught, when he erected a castle at Mfleo. in Sil Anmchadha, and the place where the castle was erected was round
the great church of that place, which was lined [or better ' filled '] ° round
with earth and stones up to the pinnacles. This passage reads as if William Burke had used the stone church
at Meelick as the core of a mote which he erected for a bretesche. " LI. 3174-201 and 8222-341. Mr. Westropp, indeed, in his paper on ' Irish
Motes and Early Norman Caatles ' (Journ. of the R. Soc. Ant. of Inland, 1904, p. 834)^
seems to take the word ' mot[e]' of the Song of Dcrmot as meaning an ' outer ring' or
rampart of earth, bnt, though in one passage I have carelessly so translated it myself,
I now feel confident that a French writer, circa 1200, by the term une mote could only
mean the mound on which a donjon, bretesche, or other fortress was built, though he
might use the word to denote both mound and fortress, i.e. as equivalent to chastel. p
p
" Pipe Boll (Ireland), 17 Ed. I, no. 20, and see Mr. Westropp's paper in Joiim.
R.S-A.L 1904, p. 340. p
11 C-D.I. vol. i. nos. 2785, 2730, 277G; and compare the account of the fortifying
of Gannok in Matt. Paris, Chron. wai. iv. 481. A letter which he quotes tells of a
disaster to an Irish ship laden with wine and other provisions at this time. • The Irish word is linad, which means ' a filling,' and so O'Donovan translates it,
Four Masters, 1203, note i. Cf. Inquis. 7th Ed. Ill, transcribed in Joiirn. R.S.A.I.
1902, p. 393 : ' There is a castle at Melok, which is inclosed by a stone wall. In it
are a stone chamber, with a chapel annexed.' This, however, was probably erected
later. ' C.D.I. vol. i. nos. S, 27.
The word in the Pipe Boll for the 18th Hen. II is
bretaschis (dative). » See below, p. 426. (
)
" LI. 3174-201 and 8222-341. Mr. Westropp, indeed, in his paper on ' Irish
Motes and Early Norman Caatles ' (Journ. of the R. Soc. Ant. of Inland, 1904, p. 834)^
seems to take the word ' mot[e]' of the Song of Dcrmot as meaning an ' outer ring' or
rampart of earth, bnt, though in one passage I have carelessly so translated it myself,
I now feel confident that a French writer, circa 1200, by the term une mote could only
mean the mound on which a donjon, bretesche, or other fortress was built, though he
might use the word to denote both mound and fortress, i.e. as equivalent to chastel.
• The Irish word is linad, which means ' a filling,' and so O'Donovan translates it,
Four Masters, 1203, note i. Cf. Inquis. 7th Ed. Ill, transcribed in Joiirn. R.S.A.I.
1902, p. 393 : ' There is a castle at Melok, which is inclosed by a stone wall. In it
are a stone chamber, with a chapel annexed.' This, however, was probably erected
later. L THE BRETESCHE. There is evidence, to which I shall refer later on, for the erection
of a mote and wooden tower (Jyritagium) in the vill of Eoscrea in
1213.1U In 1244-5 royal mandates were sent to Maurice Fitz-
Gerald, the justiciary, to cause eight wooden towers (brctachioe) to
be made in Ireland and sent by sea to the king (Henry III) to his
camp at Gannok (Degannwy), in North Wales,11 where they were
probably used on the ramparts of the castle which Henry fortified
there. As late as 1288 we have an entry on the Irish Pipe
Rolls of 10/. for a britagiwn at Caherconlish, in Limerick;" but, ' C.D.I. vol. i. nos. S, 27. The word in the Pipe Boll for the 18th Hen. II is
bretaschis (dative). BUILDING
IN IRELAND 1906 421 as it appears that there was a stone castle here at this time,
the britagium was probably a defence for the walls of the bawn,
as appears to have been the later use of the term in military
architecture. I append a list of these brittas townlands, giving the county,
barony, and parish in which they lie, and a reference to the sheets
of the six-inch Ordnance Survey maps in which they are to be
foand. Unfortunately I have not been able to examine the town-
lands themselves, but where a mote or a rectilinear fort appears
to be marked on them in the map I have mentioned it. The cases
indeed where a mote is indicated on these townlands, .particularly
on what I have called subsidiary brittas townlands, are few, and
a proper local examination would probably disclose the presence,
not of high motes, but rather of quite low mounds or raised
platforms, girt about with fosse and vallum, and these might of
course be obliterated by subsequent building or cultivation."
Where the bretesche was placed on a high mote the latter, as being
the more remarkable and more permanent feature, would be more
likely to give its name to the townland, and my preliminary
examination on the map of the mote townlands seems to show that,
outside Mayo and Gal way at any rate, this was generally so. Under each brittas name I have added historical notes which seem
to show that the bretesches were all situated on land granted to
early Anglo-Norman settlers, and usually not very far from early
castles. " I hope, now that attention has been called to these mote and Brittas townlands,
accurate information as to probable bretesche sites within them will soon be forth-
coming. L THE BRETESCHE. I have also in general noted what I suppose to have been
the special danger against which the subsidiary bretesches were
intended to guard. In some cases, however, they seem to have
been the first and principal fortresses built, and these cases were
probably far more numerous than an enumeration of the bretesche
names might lead one to suppose. For where a bretesche was at
an early date replaced by a stone castle it would not be likely to
leave its name on the townland, and the earliest bretesches, being
erected on sites selected for residence, would be the first so replaced. Occasionally indeed we find a stone castle with a Brittas name in
the Brittas townland, and presumably on the site of an earlier
wooden bretesche; but these cases may be explained by supposing
that the bretesche stood for a sufficient time to hand on its name
to the townland, or at least to the subsequent castle and through it
to the townland. In any case we may safely conclude that the
Brittas names mark only a small fraction of the bretesches that
were erected. The absence of Brittas names in extensive districts in Ireland is
almost as instructive as their presence in others. Thus there are MOTE AND BRETESCHE 422 July none that I can discover in Tirconnell (Donegal) or Tirowen
(Tyrone and Londonderry) ; none in Irish Uriel (Monaghan and
Armagh) ; none in Breiffny (Leitrim and Cavan) or Irish Annally
(the western part of Longford) ; none in Clare, except perhaps one
near Limerick; none in the western parts of Desmond. These are
just the portions of Ireland in which the English made no very
early settlement, or none of a permanent nature. M 'AntiquissLme litere patentes,' no. 68, and see 'The Norman Settlement in
Leinster,' by James Mills, Journ. R.S.AJ. 1894, pp. 163-4. Of these lands granted to
W. de Riddlesford Balimelise is identified with Ballynascomey, on the way from the
Dodder valley to Brittas.
Printed InquiB., Dublin, no. 14 Car. I. y
q
,
,
11 Tliirtij-fifth Report of Deputy Keeper of Public Records, Ireland, p. 32. In the
Pipe Boil of the 6th Ed. I the place appears as ' Bretach manor' and in that of the
7th Ed. I as ' Britach manor ' (Thirty-sixth Report, pp. 36, 41). M 'AntiquissLme litere patentes,' no. 68, and see 'The Norman Settlement in
Leinster,' by James Mills, Journ. R.S.AJ. 1894, pp. 163-4. Of these lands granted to
W. de Riddlesford Balimelise is identified with Ballynascomey, on the way from the
Dodder valley to Brittas.
Printed InquiB., Dublin, no. 14 Car. I.
11 Tliirtij-fifth Report of Deputy Keeper of Public Records, Ireland, p. 32. In the
Pipe Boil of the 6th Ed. I the place appears as ' Bretach manor' and in that of the
7th Ed. I as ' Britach manor ' (Thirty-sixth Report, pp. 36, 41).
" Printed Inquis., Dublin, no. 16, Car. I. y
" Printed Inquis., Dublin, no. 16, Car. I. LEINSTEB. BBITTAS BIG and BBITTAS LITTLE : Dublin, Uppercrots, Tallaght,
(O.S. 24).—These two townlanda are at the summit of a pass from the
mountainous district of Wicklow, from which two tracks descend into
the vale of Dublin, one leading direct towards Saggart, and the other,
apparently the more frequented in early times, by Ballynascorney to
Tallaght. Saggart or Tasaggard was a royal manor, and Tallaght an
archiepiflcopal manor, in the thirteenth century, but between Tallaght and
the mountains were lands granted by Strongbow to Walter de Riddles-
ford.14 It is certain that this pass at Brittas, though not apparently
suitable for a residential castle, was from the first a most important point
to guard against raids of the O'Byrnes and O'Tooles, who had been
driven into the mountainous districts; but whether the bretesche was
built by the custodian of Saggart or by the archbishop, or by Walter de
Riddlesford, must remain matter of conjecture. As the lands are
included in the parish of Tallaght the balance of probabilities inclines
towards the supposition that it was erected by one of the archbishops—
perhaps by Henri de Londres. Certainly it was in existence at his death
in 1228 ; for in the Irish Pipe Roll for the 18th Henry III we have an
account of the moneys received from the possessions of the see of
Dublin, then in the king's hands, and these include the sum of
'8i. 8s. 4i. from bretaschia.'13 There is no reason to doubt that this
refers to Brittas, and this record by itself really establishes the meaning
of the name. ' Brittace,' with two messuages and 300 acres of mountain
land, is mentioned in an inquisition of the time of Charles I.16 It was
then held of Sir William Parsons by fealty. BEITTAS: Wicklow, Talbotstown Lower, Kilbride (O.S. 1).—This
townland adjoins those in Tallaght already mentioned, and may have got
its name from the same bretesche. BBITTAS : Wicklow, Talbotstown Upper, Donaghmore (O.S. 22).—
This is in Imaile or ' Omail, land of Philip FitzResus, of the demesne BUILDING
IN IRELAND 1906 428 of Walter de Biddlesford.' n
A bretesche here would guard the approaches
from Glenmalure and Glendalough. A Brittas and a Little Brittas were
in Imaile in 1610.18 of Walter de Biddlesford.' n
A bretesche here would guard the approaches
from Glenmalure and Glendalough. LEINSTEB. A Brittas and a Little Brittas were
in Imaile in 1610.18 BBTTTAS : Wicklow, Arklow, Dunganstoum (O.S. 86).—The land here
belonged to Theobald Walter, the first Pincerna, who died circa 1207; 9
then in 1221 to his son.*0 There are the rains of a castle at Dungana-
town, and in the Brittas townland a square fort is marked -which
probably surrounded the bretesche. In an inquisition of the time of
James I the place is significantly called Le Brittas,11 if indeed this is
not another nearer the mountains. In fact we frequently find Brittas
names referred to as ' le Brittas' or ' the Brittas.' There was also a
Brittas in Shillelagh,31 and a Brittas and Ballinmote elsewhere in
Wicklow,13 probably at Glenealy, where there is a Ballymoat townland. Indeed it is evident that the whole district of ' Saufkeyvin, Ferchir, and
Coillac,' which was disafforested in 1229," and which for centuries was a
faatneas of the O'Byrnes and O'Tooles, was encircled with a ring of
bretesches. In 1569 a grant was made to Bobert Pifolde of' the office of
seneschal and chief ruler of the towns adjoining the Bed Mountains, in
the county Dublin, and the cross of the same from Boilenescome (Bally -
nascorney) to OmaOe, viz. the Brittas, Kilbride, Ballynagallagh, 4c, in
county Dublin, Orehelpe (Cryhelp), Dunlovan (Dunlavin), Tornanto
(Tornant moat), &o., in the cross of Dublin,' and on the same date ' a
commission to the same to execute martial law ' in the same district."
At this time the northern part of what is now county Wicklow was
included in county Dublin, and the cross of the county meant the
church lands belonging to Glendalough. BBITTAS : Meath, Morgallion, Nobber (O.S. 5).—The whole of
' Makerigalin ' (Ir. Machaire Oaileang, now Morgallion) was granted by
Hugh de Lacy to Gilbert de Nangle or de Angulo,16 who perhaps built
the first bretesche at Le Nobber (Ir. an obair, 'the work,' hence the
article). Gilbert, however, was expelled from Meath in 1196 by Hamo
de Valoignes, and was afterwards granted lands in Connaught.17
The
castle at Nobber is frequently mentioned from this time as belonging to
the De Lacys or as retained in the king's hands.88 It was evidently a very
important one as being near the northern frontier of Meath. " See the deforestation charter of the lands of Saufkeyvin, Ferchir, and Coillac,
CD./, vol. i. no. 1757.
u Printed Inqnia., Wicklow, no. 6 Jac. I.
" C.DJ. vol. L no*. 280, 882.
" Ibid. vol. i. nos. 996, 1757.
" Printed Inquis., Wicklow, no. 18 Jao. I.
" Ibid. no. 20 Car. I; ' Fiante of Elizabeth,' no. 6111 (calendared in the Appen-
dices to the 11th and subsequent Reports of the Deputy Keeper of Public Becords in
Ireland).
n Printed Inquis., Wicklow, nos. 8 and 6 Jac. L
" C.DJ. voL i. nos. 1757, 1769.
» ' Fiants of Eliz.' nos. 1415, 1416.
" Song of Dermot, 11. 8142-8.
17 'Annals of Innisfallen ' (Dublin copy), quoted in Four Master*, 1196, note I;
C.D.I, vol. i. nos. 107, 110, 811, 3M.
a Ibid. vol. i. nos. 719, 1172, 1289, 1872. The castle of Nobber was 4n existence
in 1200 (Ann. of CUmmacnoii). " See the deforestation charter of the lands of Saufkeyvin, Ferchir, and Coillac,
CD./, vol. i. no. 1757. LEINSTEB. Brittas town-
land, now a private demesne, adjoins Nobber townland, and lies about a
mile to the west of the village of Nobber, where there is an important
mote. Fort sites abound in the district. " See the deforestation charter of the lands of Saufkeyvin, Ferchir, and Coillac,
CD./, vol. i. no. 1757. " See the deforestation charter of the lands of Saufkeyvin, Ferchir, and Coillac,
CD./, vol. i. no. 1757. u Printed Inqnia., Wicklow, no. 6 Jac. I. " C.DJ. vol. L no*. 280, 882. " Ibid. vol. i. nos. 996, 1757. " Printed Inquis., Wicklow, no. 18 Jao. I. " Ibid. no. 20 Car. I; ' Fiante of Elizabeth,' no. 6111 (calendared in the Appen-
dices to the 11th and subsequent Reports of the Deputy Keeper of Public Becords in
Ireland). n Printed Inquis., Wicklow, nos. 8 and 6 Jac. L
" C.DJ. voL i. nos. 1757, 1769. » ' Fiants of Eliz.' nos. 1415, 1416. " Song of Dermot, 11. 8142-8. 17 'Annals of Innisfallen ' (Dublin copy), quoted in Four Master*, 1196, note I;
C.D.I, vol. i. nos. 107, 110, 811, 3M. a Ibid. vol. i. nos. 719, 1172, 1289, 1872. The castle of Nobber was 4n existence
in 1200 (Ann. of CUmmacnoii). q
" Ibid. no. 20 Car. I; ' Fiante of Elizabeth,' no. 6111 (calendared in the Appen-
dices to the 11th and subsequent Reports of the Deputy Keeper of Public Becords in
Ireland). n Printed Inquis., Wicklow, nos. 8 and 6 Jac. L " C.DJ. voL i. nos. 1757, 1769. 17 'Annals of Innisfallen ' (Dublin copy), quoted in Four Master*, 1196, note I;
C.D.I, vol. i. nos. 107, 110, 811, 3M. a Ibid. vol. i. nos. 719, 1172, 1289, 1872. The castle of Nobber was 4n existence
in 1200 (Ann. of CUmmacnoii). MOTE AND BRETESCHE 424 July BBITTSTOWH : Meath, Upper Slaw, Slane (0.8. 19).—This ia an
interesting and important example, as it seems to have a direct bearing
on the nature and exact position of the ' mote' which Richard the Flem-
ing threw up at Slane, and where he was killed in 1176, as recorded in
the Song of Dermot in a much disputed passage.19 That it is a bretesche
name is, I think, almost certain. Townland names, which elsewhere begin
with ' bally,' in Meath, as is well known, usually end in ' town ' instead. ** LL 8174 ei seq., where for the corrupt Crandone we should probably read Slan
donat, as Mr. Bonnd baa pointed oat (Commune of London, p. 143). Here we are
told of Bicard le flemmeng : ** LL 8174 ei seq., where for the corrupt Crandone we should probably read Slan
donat, as Mr. Bonnd baa pointed oat (Commune of London, p. 143). Here we are
told of Bicard le flemmeng :
Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer.
Then follows an account of the Irish attack and the destruction of the meison and
its garrison, with which compare Ann. of UUter, 1176.
M The townland and mote would seem to be included in the denomination Mona
de Slane in the Inqnis., Meath, no. 7 Car. I, concerning the lands of Christopher,
baron of Slane.
" This description is taken from Mr. Westropp's paper on Slane in Bregia,
Journ. B.S-A.I. 1901, p. 416.
" Four Masters, 1176 and note e. LEINSTEB. Thus Brittstown is the equivalent of Ballybrittas, so often met with
elsewhere. Now this townland of Brittstown adjoins Slane demesne
exactly at the place where ' the moat of Slane' stands, and it seems a
very slight assumption that before this part of the demesne was inclosed
the townland included the mote.*0 The mote is close to the monastery,
and is separated from the principal part of the demesne, in which the
later castle now stands, by the public road from Navan to the village of
Slane. The mote is ' a great truncated cone of earth and rock splinters
rising twenty-seven or twenty-eight feet above the fosse' which surrounds
it. ' The level summit is ninety feet across, and has a very slight ram-
part. The fosse, from sixteen to eighteen feet wide, and from six to ten
deep, is cut in the rock, and is girt with a slight outer ring.' There is
' another ring with a very slight mound and a shallow fosse,' somewhat
eccentrically placed.31 It may be, as Mr. Westropp says, and indeed as I
assumed when visiting the place some years ago, a primitive sepulchral
mound ; but I now think, taking the record from the Song of Dermot in
connexion with the finding of a bretesche name on the spot, that it was
the mote on which Richard the Fleming erected his fortress, and that
thin fortress was a bretesche,. If there was a mound in existence at all
suitable to his purpose he would not go to the labour of erecting another,
and tb.9 ghnping and fortifying of an existing mound would be quite
enough to account for the words of the Song of Dermot, where we
should not look for perfect accuracy of expression. It is worth noting
that the castle of Galtrim, stated by the Four Masters to have been
destroyed by the Irish at the same time as the castle of Slane, was in all
probability situated in the townland of Galtrim, barony of Deece, where
there is also a mote.*1 BBICTAS : Westmeath, Magheradernon and Moyashel, Bathconnell
(O.S. 12,19).—Magheradernon was granted by Hugh de Lacy to William
le Petit. I have transcribed an early copy of this charter in my notes to
the Song of Dermot, from which it appears that an exception from the Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer. M The townland and mote would seem to be included in the denomination Mona
de Slane in the Inqnis., Meath, no. 7 Car. I, concerning the lands of Christopher,
baron of Slane. p
" Four Masters, 1176 and note e. Then follows an account of the Irish attack and the destruction of the meison and
its garrison, with which compare Ann. of UUter, 1176. Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer. g
Then follows an account of the Irish attack and the destruction of the meison and
its garrison, with which compare Ann. of UUter, 1176. M The townland and mote would seem to be included in the denomination Mona
de Slane in the Inqnis., Meath, no. 7 Car. I, concerning the lands of Christopher,
baron of Slane. " This description is taken from Mr. Westropp's paper on Slane in Bregia,
Journ. B.S-A.I. 1901, p. 416. " This description is taken from Mr. Westropp's paper on Slane in Bregia,
Journ. B.S-A.I. 1901, p. 416. BUILDING IN IRELAND 425 1906 grant was made of Bau&konill (now Bathconaell), as it had already been
granted to ' Adam de Totipon,' probably, as Mr. Round has suggested,
the Adam de Fntepoi of Giraldus, better known as Adam de Feipo."
Giraldus mentions among the easteila that Hugh de Lacy built in Meath
one for this Adam de Feipo, but this may have been the castellum ruxta
Scrinium (Skreen), where Adam afterwards lived.*4 As the surrounding
districts were occupied from the first by English settlers this bretesche
may have been the first fortress built at Bathconnell and not a subsi-
diary tower. There seem to be remains of a mote marked on the map,
but of this I am not sure. BBITTAS : Westmeath, barony and parish of Kilkenny West (O.S. 22,
23).—This was in the district of Cuircne or Machaire Chuircne, which
is said to have become the inheritance of the Dillons shortly after
the English invasion."
According to the family traditions the first
Dillon came over with John in 1185.M Certainly Magheryquircke was
known in later times as 'Dillon's country.' A castle was built in the
adjoining barony at Bathouanartaigh, now Bathconrath, in 1191. It
was on the lands of Geoffroi de Constentyn.87 The royal castle of
Athlone was built by John, bishop of Norwich, in or before 1210,*8 and
this bretesche may have been constructed in connexion with it to guard
the road from Anghailn (part of Longford), where the Irish for many
years retained their hold on the land. There seems to be a mote (though
not so named) in the townland, which is near Waterstown House. )
,
BRTTTAS : Louth, Ferrari, Carrickbagot (O.S. 18, 21).—This district
seems to have been acquired by Bertram de Verdon. He came over
with Henry II,-9 and was seneschal of Ireland. ** Song of Dermot, 11. 8185-6 and note on p. 310, and Bound's Commune of Lo
p. 142.
** Expvgnotio Hib&rnica, B. 8. p. 856 ; Chart of St. Mary's Abbey, vol. ii p. 2
also Annals there printed, p. 276.
a Topographical Poems of O'Dnbhagain and O'Hoidrin, edited bj J. O'Donovan;
referred to aa Topogr. Poem*.
" Journ. B.8UJ.
1872-3, p. 878. Archdall's Lodge, voL iv. p. 186.
" Annals of Loch Cl, 1191; ot Song of Dermot, 1L 815i-5, where ' Kelberi and
Batheimarthi' are corruptions for Eelbixl and Bathcunarthi
CJ)J. i. 507.
** Four Masters, 1210.
" Song of Dermot, L 2610; Ware'i Antiquities, ed. Harris, p. 197.
• CS>.l. vol. i. no. 185.
« Ibid. no. 251.
« Ibid. no. 790.
u Ibid. no. 1210; of. Four Masters, 1221. J. vpL I no.. 1883. The evidence leads, I think, to' a moral certainty, though
it does not perhaps amount to legal proof but it is too long £>\nsert here.
II
C.DJ.
new. H67, 1642, 1568,1623, 1676, 1718, 1821, 1829, 1883, 1889, 1902, 1923, 2024 and
2029 be consulted, it will be seen that the action, originally brought by Bajph Bagod,
became split into two, and concerned the whole parish of Carrickbaggot (composed
of the townlands of Carrickbaggot and Brittas) and the townland of Baggotstown, in
the parish of Bathdrnmmin ; and these Baggot 'names indicate that the action was
successful.
The acreages roughly correspond, and the appearance on the map of the
parish of Carrickbafegot—an almost perfect square, bordered on the north and east
sides by the parish of Bathdrummin—indicates that it was levered from the larger
district, which was ' the Bath ' of Balph Bagod's action. Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer. He died in Bichard I's
crusade, and was succeeded by his son Nicholas. In 1208 Nicholas was
given the custody of the castle of the Bridge of Drogheda, as his father
held it,40 and in 1204 his father's lands were restored to him/1 from
which we may infer that he had sided with John de Courcy and had
temporarily forfeited his lands. He again forfeited his lands at the close
of John's reign, but they were again, restored to him in 1217.4* The
entry here shows that he held half the cantred of Ponte Ferrardi (now
the barony of Ferrard) as well as the castle of Dundalk. In 1224 he
represents his lands as laid waste by Hugh de Lacy's war." Some
actions relating to lands were brought against him by his tenants and
neighbours, but they were respited from time to time while he was in
England on the king's service. One of these actions concerned five MOTE AND BRETESCHE 426 July oarucates of land ' in La Bretasch,' and I think it can be shown beyond
any reasonable doubt that this included the land now represented by the
townland of Brittas in the parish of Carrickbaggot."
This instance alone
seems to me sufficient to prove the equivalence of Brittas and Bretesche. The map seems to show a large mote on the Brittas townland. BALLYBBITT : King's County, BaUybritt,
Aghancon (0.8. 89, 43).—
I think I can show that this is a bretesche name. In the Annals of
Ulster, under the year 1482, the castle that was erected here is called ' the
castle of Bails an britaigh,' where britaigh is in the genitive and points
to a nominative britach;
this I take to be an attempt to reproduce in
Irish some form of the word bretesche, such as brytaike, and so Baile an
britaigh would be equivalent to the usual Anglicised form Ballybrittas. The place is called Ballenbret in the ' Fiants of Elizabeth ' (no. 6786),
where the article is preserved. The shortened form Ballybrit may be
due to a supposed etymology involving the word Britt, a Briton. Baile
an britaigh would be more regularly Anglicised Ballinbritty, as we shall
find was formerly the case with Ballybrit, near Galway, or, in Munster,
Ballinbrittig, as the name appears in Barrymore, county Cork. Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer. The town-
land of Ballybritt, King's County, is in the ancient district of Eliocarrol,
and the site of the bretesche is probably marked by the later stone castle
of Ballybrit, about four miles north of the town of Eoscrea. I would
ascribe the erection of the bretesche here to about the year 1218, when a
number of castles were built in the neighbourhood. Indeed we have in-
teresting historical evidence of the erection of a mote and bretesche in
the vill of Roscrea in this year, and though perhaps frhin refers to a fort-
ress in the town of Roscrea it has sufficient importance with regard to
the general question -of the nature of early Norman castles in Ireland to
merit a somewhat detailed statement. On 5 July 1245 an inquisition was taken at Roscrea as to whether
the lands of Roscrea ought to belong to the bishopric of Killaloe, by
whom they were alienated, and what they were yearly worth, and the
finding of the jurors is calendared as follows :— In time past Mnrchercath MaoBren ravaged the land of Harmon and Hely
Okarvill [Le. Onnond and Ely O'CarroIl], and levelled five castles there, where-
upon the k.'a force and council in Ireland assembled at Eoscrea to expel Murch-
chert. .The lands were at that time in the hand of Cornelias O'Heny, then
bishop of Killaloe, as of right belonging to his bishopric. The k.'s council com-
menced fortifying a castle in the vill of Roscrea by erecting a moat and a
wooden tower \brUagium]. Meanwhile Henry, archbishop of Dublin from
England, justiciary of Ireland, repaired by King John's direction to the vilL
Hearing this, Bishop Cornelius came thither and prohibited a castle or any BUILDING
IN IRELAND 427 1906 fortification from being constructed in his ecclesiastical possessions; and said
that if they proceeded further therein he should excommunicate the justiciary
and the whole army. Thereupon the justiciary and the army prayed Bishop
Cornelius, on behalf of the k. and for the common good, that they might be
allowed to fortify the moat and wooden tower until the termination of war,
undertaking in the k.'s name that the bishop should then have the vill and its
appurtenances or the just value thereof. The bishop thereupon granted per-
mission accordingly. In this manner the lands of Boscrea were alienated. u Inq. P. M. 29 Hen. m , no. 43, CD J. vol. i. 2760. The castle of Boscrea remained
a royal castle, and ultimately, in 1280, Edward I granted 3 carucates and 84£ acres of
land in the manor of Newcastle, near Lyons, to Matthew, bishop of Killaloe, in exchange
for ' the manor of Roscrea, which he had for some lime possessed ' (C.D.I, vol. ii. 1663,
1664; cf. Irish exchequer memoranda of the reign of Edward I, Engl. Hist. Rev. xviii.
609, and Irish Pipe Boll, 10 Ed. I, in the Thirty-sixth Report of Deputy Keeper, p. 61)
*• Journal R.S.AJ. 1904, pp. 839, 316. Mr. WeBtropp does not say who the
justiciary was, nor notice that the interview between him and the bishop took place
in John's reign. He says the bishop was a Daleassian and one of the O'Kennedys,
and that it was a raid of Murchard O'Brien, also a Daleassian, that brought the
justiciary to Boscrea, whereas the bishop was an O'Heney and the raider an O'Conor.
" The Annals of Clonmamois (1207 et sea.) give many details of this Murtongh
son of Brian, and of his ravaging Ormond and Ely O'CarroLl, and destroying the castles
there, which fully bear out the finding of the jurors; also of the castle-building by
the English to hold the frontier. At Athlone, Clones, Boscrea, Clonmacnois, Birr,
Durrow, and Kinnitty castles were either built, rebuilt, or finished between the
years 1210 and 1213. j
y
p
y
" The Annals of Clonmamois (1207 et sea.) give many details of this Murtongh
son of Brian, and of his ravaging Ormond and Ely O'CarroLl, and destroying the castles
there, which fully bear out the finding of the jurors; also of the castle-building by
the English to hold the frontier. At Athlone, Clones, Boscrea, Clonmacnois, Birr,
Durrow, and Kinnitty castles were either built, rebuilt, or finished between the
years 1210 and 1213. Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer. The mention of
a moat (by which at this date, I think, we must understand a mound) as
well as of a britagium seems to negative the idea that it was a mere
adjunct to a stone castle at Boscrea—besides, as such, it could hardly
have been objected to by the bishop—and to point to its being a complete
and distinct fortress, wherever placed. It seems to me that either it was
the castle of Roscrea, stated in the Irish annals to have been erected in
1212—in which case we may reconcile the date with the findings of the
inquisition by supposing that the castle, though begun in 1212, was not
completed, owing to the bishop's threats, until the autumn of 1218—
or it was a subsidiary fortress placed somewhere on the marches of the
vill of Roscrea, which ' the custodee of Eoscrea received as his fee,' per-
haps even on the site of the later stone castle of Ballybritt, though that
is a little outside of the present parish of Roscrea. In favour of the
latter supposition it may be observed that the royal castle of Roscrea,
built by John de Gray in 1212, was probably of stone, like that of Athlone,
built by the same justiciary two years before, and if so it must be distin-
guished from the mote and bretesche of 1218, while the name Ballybritt,
as we have seen, points to a bretesche having been at some time erected
there. BALLYBBITTAS : Queen's County, Portiiahinch, Lea (O.S. 5, 9). BBITTAS : Queen's County, Tinnahinch, Kilvuinnan (P.S. 2).—These
three bretesches were in Offaly, on the borders of Leix. The lands which
they seem to defend belonged before the close of the twelfth century to
Gerald, son of Maurice FitzGerald, by whom probably the first castles of
Lega (Lea) and Geisil (Geashill) were erected. At any rate castles were
in existence there and in Gerald FitzMaurice's hands about the close of the
twelfth century.118 Ballybrittas (old) is three miles due south of the castle
of Lega, Ley, or Lea, which was on the Barrow. It is marked on the old
map of Leis and Offalie (circa 1563) as Balybryttis.4" It was in Clan
Malier, or O'Dempsy's country, a subdivision of Offaly.50
The townland
includes Glenmalier House, which has a rath in its grounds. By the
name Ballybrittace it was granted by Elizabeth to an O'Dempsy. Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer. These lands are annually worth thirty-five marks of silver, and the custodee of
Roscrea receives the marches as his fee.44 This important finding has been strangely misinterpreted by Mr. Westropp in his interesting paper on Irish motes and early Norman
castles. He calls it a record of the building of a mote and bretasche
at Roscrea in July 1245, whereas that is only the date of the inqui-
sition. He says the castle had been erected thirty-three years before,
an inference from the false date. He further says that' it is evident
from this record that there was no time to heap up a large mound for the
support of the wooden tower,' and in another passage that ' the moat at
Boscrea was apparently completed before a messenger could go thirty
miles and return with permission to built it.'46 But there is nothing in
the inquisition to warrant these statements. q
It so happens that it is easy to date the erection of this mote
and bretesche and to show the substantial accuracy of the inquisition. It was erected, according to the inquisition, in the time of Cornelius
O'Heny, bishop of Killaloe. His obit is given by the Four Matters
under the year 1215 : ' Conar (Cornelius) O'Heney, bishop of Killaloe,
died on his return from the fourth general council of Lateran.'
So the
bretesche was built before that date. The justiciary too was Henri de
Londres, archbishop of Dublin, who was appointed justiciary on 23 July
1213 ; so the meeting between him and the bishop took place after that
date and probably in that year. Now if we turn to the Four Masters
under the year 1212 we read, ' An army was led by the English of
Munster to Roscrea, where they erected a castle. From thence they pro-
ceeded to Killeigh [in the barony of Geaahill], where they were over-
taken by Murtough, son of Brian [O'Conor], and his army, who gave them
battle.' This is the Murchercath MacBren of the inquisition/7 428 MOTE AND BRETESCHE July Where exactly was this mote and bretesche erected ? u C.DJ. vol. i. nofl. 101, 195. These castles seem to have been in the hands of
William Mareschal daring the minority of Maurice FitzGeruld, to whom the; were
delivered in 1216 (ibid. no. 724).
'• Journ. R.8-A..I. 1862, facing p. 345.
" Topogr. Poems, p. 84, note 419.
J1 ' Fiants of Eliz.' 634, 1654.
" Printed Inqnis., Queen's Co., no. 4 Jac. I.
" Topogr. Poems, p. 82, note 411.
" C.DJ. vol. ii. p. 424. " Printed Inqnis., Queen's Co., no. 4 Jac. I. " Topogr. Poems, p. 84, note 419 " Topogr. Poems, p. 82, note 411 J1 ' Fiants of Eliz.' 634, 1654.
" C.DJ. vol. ii. p. 424. Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer. It is
also spelled Ballibrettys and Ballybrettas.41
The bretesche in Ardea was
in Irry, another subdivision of Offaly, and in Stuart times was part of the
vill of Shean,'" where there is an old castle. The bretesche in Kil-
mannan was in Iregan, or O'Dunn's country, also a subdivision of Offaly.'3
The townland is situated near Clonaslee, on the lower slopes of Slieve
Bloom, commanding a mountain pass from Leix as well as the route from
Fircal and Ely O'CarrolL It was held of Maurice FitzGerald by John
FitzThomas, who was killed at Callan in 1261.w
Under the Stuarts it
was owned by a Dunn, and under the name of Brittas House it is still, J1 ' Fiants of Eliz.' 634, 1654. " C.DJ. vol. ii. p. 424. BUILDING IN IRELAND 429 1906 I believe, in the hands of a representative of the old chieftain/11 The
O'Mores of Leix appear to have been left in possession of a con-
siderable part of their territory, perhaps at first because the chieftain
sided with Dermot McMurrough and Strongbow.36 Much of Offaly too
remained in the hands of the O'Conors Faly. The castles of Lea and
Geaahill and these three bretescb.es lay along the upper valley of the
Barrow, as it were in a wedge driven in between these two Irish
districts. BBITTAS : Kilkenny, Crannagh, Tullaroan (O.S. 18, 18). BBITTAS DKYLAND : Kilkenny, Crannagh, Kilmannagh (O.S. 22).—
The former townland is situated in a district known as Grace's Country,
to the north of the village of Tullaroan. In spite of assertions to the
contrary it is quite certain that the family of Grace was not descended
from Raymond le Gros." William le Gras, or Willelmus Crassus,
appears to have been a friend and follower of William Mareschal,5" and a
person of the same name, probably a descendant, held the quarter of a
knight's fee in Tullaroan in 1247 at the time of the Leinater partition.5*
A deed of the year 1288, however, makes it doubtful if this family had
been long in possession of lands in Tullaroan.60 In 1623 John Grace
late of Courtstown was found seised of the manor of Tullaroan, and the
lands mentioned as belonging to him include Brittasmore, i.e. •» Printed Inqnia., Queen's Co., no. 7 Jac. I and 2 Car. n. See Four itaaten, 148
p. 958.
M Song of Dermot, 11. 1265, 3218.
" See Miss Hickson's paper, Journ. U.S.A.I. 1896, p. 227.
" See paper by Mr. Langrishe on the ' Origin of the Grace Family of Courtotown,'
Journ. B.S.A.J. 1900, p. 319.
•• Chart, of St. Mary's Abbey, Dublin, vol. ii. p. 405.
- CM.I. vol. ii. no. 2168.
" Thk Brittas townland adjoins Tnllaroan townland, where there is a mote.
" Printed Inqais., Kilkenny, no. 39 Jac. I. •» Printed Inqnia., Queen's Co., no. 7 Jac. I and 2 Car. n. See Four itaaten, 148
p. 958. " See paper by Mr. Langrishe on the ' Origin of the Grace Family of Courtotown,'
Journ. B.S.A.J. 1900, p. 319. p
M Song of Dermot, 11. 1265, 3218. g
f
" See Miss Hickson's paper, Journ. U.S.A.I. 1896, p. 227 ,
f
y
- CM.I. vol. ii. no. 2168. J
, p
•• Chart, of St. Mary's Abbey, Dublin, vol. ii. p. 405. Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer. BALLYBBTTTAS : Wexford, Bantry, Clonmore (O.S. 81). BAiiLYBBiTTAS: Wexford, Bantru, Kilcowanmore (O.S. 25, 81).—
Clonmore was included in the 'barony of Kayer' or Cloghnekairagh
(Clock tux gCaerach), created, perhaps, by Strongbow, certainly prior to the
deforestation charter of Bichard Mareschal (1281-4), where we find
the river Glanbother, a little stream north of the parish of Carrick,
alluded to as the division inter terrain meam et terram baronis d-e Z«r.65
Kilcowanmore must also have been granted, probably to a Keating, at
a very early time. In the extent of the lands of Aylmer de Valence
(1828-4) Adam Keting was found to hold half a knight's fee in Kilcouan ; M
but this was probably Kilcowan, in the barony of Bargy, whither we may
suppose the Eeatings retired when the Irish grew too strong for them in
Bantry. Still they held on to, or recovered, some of their old lands
in Kilcowanmore; for in 1628 a Keating of Kilcowan was seised of
' 1 carucate of land portion of 7 caruoates in Ballybrittas, Fannigh, and
Kilcownemore, in Fassaghbantry.'6T BAiiLYBBiTTAS: Wexford, Bantru, Kilcowanmore (O.S. 25, 81).—
Clonmore was included in the 'barony of Kayer' or Cloghnekairagh
(Clock tux gCaerach), created, perhaps, by Strongbow, certainly prior to the
deforestation charter of Bichard Mareschal (1281-4), where we find
the river Glanbother, a little stream north of the parish of Carrick,
alluded to as the division inter terrain meam et terram baronis d-e Z«r.65 BAiiLYBBiTTAS: Wexford, Bantru, Kilcowanmore (O.S. 25, 81).—
Clonmore was included in the 'barony of Kayer' or Cloghnekairagh
(Clock tux gCaerach), created, perhaps, by Strongbow, certainly prior to the
deforestation charter of Bichard Mareschal (1281-4), where we find
the river Glanbother, a little stream north of the parish of Carrick,
alluded to as the division inter terrain meam et terram baronis d-e Z«r.65 Kilcowanmore must also have been granted, probably to a Keating, at
a very early time. In the extent of the lands of Aylmer de Valence
(1828-4) Adam Keting was found to hold half a knight's fee in Kilcouan ; M
but this was probably Kilcowan, in the barony of Bargy, whither we may
suppose the Eeatings retired when the Irish grew too strong for them in
Bantry. Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer. Still they held on to, or recovered, some of their old lands
in Kilcowanmore; for in 1628 a Keating of Kilcowan was seised of
' 1 carucate of land portion of 7 caruoates in Ballybrittas, Fannigh, and
Kilcownemore, in Fassaghbantry.'6T These two townlands adjoin each other and probably form only one
Brittas district. The portion in Clonmore is only about two acres. I
have visited this district, and found just outside its southern border, in a
townland with the apparently modem name of ' Sparrowsland,' a rect-
angular fort surrounded by a deep and wide fosse which was capable of
being flooded by a neighbouring runlet of water. I suspect that this was
the site of the bretesche. a Chart, of St. Mary's Abbey, Dublin, vol. ii. p. 402 ; of. p. 144.
w I quote from a transcript made by Mr. Herbert Hore of the inquisition once
preserved in the Hibemia Bag in the Chapter House, Westminster.
"» Chart, of St. Mary's Abbey, Dublin, vol. ii. p. 157.
•• Inquis. P.M. 17 Edw. n, no. 75.
" Printed Inquis., Wexford, no. 38 Car. I and 127 Car. I. f
y
y
•• Inquis. P.M. 17 Edw. n, no. 75. " Printed Inquis., Wexford, no. 38 Car. I and 127 Car. I. Un[e] mot{e] fiat cil ieter
Pur tea enemia greuer. the Brittas
townland in the parish of Tullaroan,61 and ' Brittas-maris, otherwise
Brittas-flugh,' which was held of the manor of Ballynamara, and was
probably in that parish near Gaulstown Castle.62 This name is evidently
translated in the inquisition, just as in the next denomination we have
1 Englis towne, otherwise Ballinegaule,' probably now Gaulstown. ' Flugh ' I take as the Irish fluich—wet, marshy—and ' mans' evidently
represents the French marais. This survival of a French word in con-
nexion with Brittas is significant. Brittas Dryland, in the parish of Kilmannagh, appears as Brittas
Drilling (perhaps B. na d-tri linne, or the Bretesche of the Three Ponds)
in the Book of Survey and Distribution. It is near the Castle of Pottle-
rath and contains a remarkable pentagonal rath. About two miles north of Inistiogue, in county Kilkenny, there was
another bretesche which has left its name on a hamlet, but not on the
townland. The site of Brittas Castle is marked here. There is a large
flat-topped mote surrounded on the top by a (modern ?) wall at Inis-
tiogue. g
BBITTAS: Wexford, Forth, Kilscoran (O.S. 48).—The parish of
Eilscoran adjoins' that of Bosslare, which was a manor of William
Mareschal. On the partition of the lordship of Leinster Bosclar (the •» Printed Inqnia., Queen's Co., no. 7 Jac. I and 2 Car. n. See Four itaaten, 148
958 MOTE AND BRETESCHE 430 July true form of the name, meaning probably the ' peninsula of the plank
bridge') fell to his daughter Johanna and through her daughter to the De
Valences.8' From an inquisition into the state of the Ostmen in the
county of Wexford taken in the year 1283 it appears that in the time of
the Mareschals the demesne at Eosclar was worked by Ostmen under
semi-servile conditions for their lord's benefit*4 It may be inferred with
probability that a colony of the dispossessed Ostmen of Wexford was
placed here. The erection of a bretesche at a very early period of the
English occupation guarding the only exit by land from the peninsula is
what we might expect. As the barony of Forth was -almost from the
first well planted with settlers there could hardly have been any need
for this bretesche after all apprehension of a Scandinavian attack had
passed away. p
y
BALLYBBTTTAS : Wexford, Bantry, Clonmore (O.S. 81). BALLYBBTTTAS : Wexford, Bantry, Clonmore (O.S. 81). a Chart, of St. Mary's Abbey, Dublin, vol. ii. p. 402 ; of. p. 144.
w I quote from a transcript made by Mr. Herbert Hore of the inquisition once
preserved in the Hibemia Bag in the Chapter House, Westminster. g
p
,
"» Chart, of St. Mary's Abbey, Dublin, vol. ii. p. 157. •• Inquis. P.M. 17 Edw. n, no. 75. MUNSTEB. BBITTAS : Cork, Ibane and Barryroe, Ardfield (O.S. 185). BBITTAS : Cork, Ibane and Barryroe, Ardfield (O.S. 185). 8 BBITTAS TOWNLANDS : Cork, Ibane and Barryroe, Island. 8 BBITTAS TOWNLANDS : Cork, Ibane and Barryroe, Island. BBITTAS: Cork, Ibane and Barryroe, Kilkerranmore.—When and
how exactly the Barrys got possession of this barony is obscure to
me, but for present purposes this is of the less importance as we have
evidence that in the year 1215 a war broke out between two of the BUILDING
IN IRELAND 491 1906 MacCarthys, and the English, assisting on both sides, acquired great
possessions and made great conquests of lands, on which they built
castles and strong forts for themselves, to defend them against the Irish. Among the castles erected on this occasion were the castles of Timoleague
and Dundeady, built by Nicholas Boy de Barry." There are remains of
stone castles at Timoleague and Dundeady, in this barony. These five
Brittas townlands are all close together, and possibly may not indicate
more than one bretesche. BHITTAS : Cork, DuhaUow, Kilshannig (O.S. 82,41).—This bretesche
appears to have been near the frontier of the territories granted to or
acquired by Robert Fitz Stephen in 1177 ;69 for by arrangement with
Milo de Cogan, his co-grantee, he took three cantreds near the town of Cork
on the east, and Mflo four cantreds on the west.70 It is unnecessary to
consider precisely what these three cantreds were, as it is certain they in-
cluded the territories known as' Olethan' (i.e. Ui Liathain, now the barony
of Barrymore) and ' Muscherie Dunegan ' (i.e. Muscraighe Donnagain, a
territory somewhat larger than the barony of Orrery and Kilmore); for
these two territories, together with ' Killede,' which I think has not with
certainty been identified, were granted by John in 1207 to William de
Barry in confirmation of the gift made by Robert Fitz Stephen to Philip
de Barry, William's father.71
The intervening barony of Fermoy was at
an early period in the hands of the Roches, and the manor of Mallow
passed from them to Thomas FitzMaurice, father of the first earl of
Desmond, before 1282.™ The Brittas townland runs south from the
Blackwater in the direction of the Boggerah Mountains : Brittas House
is marked here. BALIJNBBITTIG : Cork, E.B., Barrymore, Carrigtohill (O.S. 64, 75).—
This, I think, is clearly a Brittas name. " Bee O'Donoyan's note to the Four Masters, 1215, pp. 187-8, where he refers
to the Dublin copy of the ' Annals of Innisfallen,' and gives a long list of castles built
at this time in Kerry and Cork. Most of these castles°were destroyed after the battle
of Gallon (Four Masters, 1361, note uj.
" Ware's Antiquities, ed. Harris, p. 19a
n Giraldus, v. 348.
" Chart. Boll, 9 John, CJ)J. voL i. no. 840; of. Giraldu*. v. 861.
n See Inqms. as to lands of John FitzThomas, CJ).I. a. 1383, p. 439, where
Moyale = Magh Kalla, now Mallow.
n The final g is preserved, according to a well known tendenoy of the Monster
dialect. It is, no doubt, the place called BaHynbrittige in • Plants of Elii." no. 6575.
" See Four Masters, 1063. The name appears in the State Papers as Heyghana-
cassel, Yonaichcassel, Jonaychcassel, Ac. " Bee O'Donoyan's note to the Four Masters, 1215, pp. 187-8, where he refers
to the Dublin copy of the ' Annals of Innisfallen,' and gives a long list of castles built
at this time in Kerry and Cork. Most of these castles°were destroyed after the battle
of Gallon (Four Masters, 1361, note uj. n See Inqms. as to lands of John FitzThomas, CJ).I. a. 1383, p. 439, where
Moyale = Magh Kalla, now Mallow. n The final g is preserved, according to a well known tendenoy of the Monster
dialect. It is, no doubt, the place called BaHynbrittige in • Plants of Elii." no. 6575.
" See Four Masters, 1063. The name appears in the State Papers as Heyghana-
cassel, Yonaichcassel, Jonaychcassel, Ac. n The final g is preserved, according to a well known tendenoy of the Monster
dialect. It is, no doubt, the place called BaHynbrittige in • Plants of Elii." no. 6575. dialect. It is, no doubt, the place called BaHynbrittige in • Plants of Elii. no. 6575.
" See Four Masters, 1063. The name appears in the State Papers as Heyghana-
cassel, Yonaichcassel, Jonaychcassel, Ac. (
,
,
j
" Ware's Antiquities, ed. Harris, p. 19a 17 Ibid. nos. 857, 920, 923; of. the case of the^bisbopof Killaioe and Boscrea, above,
pp. 426 seq. " CJ>.l. vol. i- nog. 601, 618 ; of. no. 289. Knockgraffon was erected in 1192 inside
the Irish rath (Four Masters and O'Donovan'e note). Ardmayle is about three miles
north of Cashel. The mins show a circular tower (Lewis).
KiltSnan (called Kiltenanan
in the records) is near Fethard and has a circular tower with walls seven feet thick
(Lewis). " Fraser's Handbook of Ireland, 8th ed. p. 86.
M pp
q
n C-DJ. voL L nos. 1624,1938,1634,1689. M Topogr. Poems, notes 759 and 771. '• C J)J. voL i. no. 838. MUNSTEB. As we have seen the Annals of
Ulster under 1482 refer to Ballybritt Castle, near Rosorea, as Baile an
Britaigh, which seems to be a Hibemicised form of Ballybrittas, or the
Town of the Bretesche. This Hibemicised form has, I think, exactly
survived in Ballinbrittig,7* in Barrymore. Barrymore, as we have seen,
was granted under the name of Olethan to Philip de Barry, and the
grant was confirmed by John to William de Barry, Philip's son. The
aadile of Carrigtohill is said to have been built by Philip. The manor of
Karetto Thell (read Earectothell) or Kareotohell is mentioned in 1284. It then belonged to David Barry. The castle has been known for centuries
as Barryscouri BEITTAS : Tipperary, Middlethird, St. Patrick's Bock (O.S. 60).—This
was included in the Irish territory called Eoghanacht Chaisil.74 It was MOTE AND BRETESCHE 482 July granted, together with some adjoining cantreds, in 1215 to Philip of
Worcester, ' to Tnnintain him in the king's service.' At this time the
castles of Knockgraffon, Ardmayle, and Kilting all in Middlethird, were
in existence.75 So Philip was, of course, not the first grantee. It was, I
think, inoluded in the lands of William de Burgh taken into the king's
hands in 1206. In 1218 the district was again taken into the king's
hands.76 In the same year Donat O'Lonargan, archbishop of Cashel,
complained that ' the justiciary had disseised him of the new vill of
Cashel and of the greater part of the old vill,' and in 1219 threatened
interdict and excommunication unless restitution was made.77 Even-
tually in 1228 restitution was made to his successor for BOO marks.78
The Brittas townland lies north-west of the Bock of Cashel, between it
and Camus House, at a later time at any rate the residence of the arch-
bishop. Borne very remarkable earthworks are marked round Kilbrista
Church ruins, in the adjoining townland, suggesting that perhaps the
church occupied the site of a bretesohe. granted, together with some adjoining cantreds, in 1215 to Philip of
Worcester, ' to Tnnintain him in the king's service.' At this time the
castles of Knockgraffon, Ardmayle, and Kilting all in Middlethird, were
in existence.75 So Philip was, of course, not the first grantee. It was, I
think, inoluded in the lands of William de Burgh taken into the king's
hands in 1206. MUNSTEB. In 1218 the district was again taken into the king's
hands.76 In the same year Donat O'Lonargan, archbishop of Cashel,
complained that ' the justiciary had disseised him of the new vill of
Cashel and of the greater part of the old vill,' and in 1219 threatened
interdict and excommunication unless restitution was made.77 Even-
tually in 1228 restitution was made to his successor for BOO marks.78
The Brittas townland lies north-west of the Bock of Cashel, between it
and Camus House, at a later time at any rate the residence of the arch-
bishop. Borne very remarkable earthworks are marked round Kilbrista
Church ruins, in the adjoining townland, suggesting that perhaps the
church occupied the site of a bretesohe. In the parish of Magorban, to the east of Cashel, are the townlands
Knockbrit and Bathbrit. Each contains a somewhat peculiar rectangular
fort, but forts of all kinds are very numerous about here. Probably,
as in the case of Ballybrit (King's County and Galway) and Mullybrit
(Fermanagh), these are bretesche names. These five are the only names
in -brit that I have come across. I suspect that these bretesohes mark stages of the encroachment
against which the archbishop protested successfully. The Bock of
Cashel must have been a tempting objective to the English in this
region. BBITTAS:
\lSpperary. Eliogarty, Thurles (O.S. 85, 41).—
BBITTASBOAD :
J
rtr^
*
^
"
v
' BBITTAS: •» O'Clory's Book of Pedigrees.
The portion referred to ia printed and translated,
in Journ. R.S-AJ. 1879-82, p. 423.
•» CJ)J. vol. i. no. 2fi73.
M Ann. of Loch Ct, 1200; CJ)J. voL i. no. 2423, .grant to Eiohmrd de Burgh
of a weekly market in his manor ol Castle Cuvyn (read Cnnyn), i.e. Caislen Connaing,
now Oastleoonnell; of. no. 2807.
•» Praser's Handbook of Inland, p. 895.
M CMJ. vol. i. nos. 147, 788.
•» Topogr. Potms, note 817.
u CJDI. vol. i. no. 1618 ; of. Journ. R.8-A.J. 1901, p. 865.
" Four Masters, 1283. There had been an earlier castle erected by the Irish in
1124.
" Ibid. 1237,
•» Ibid. 1238.
VOL. XH.
NO. T.TTTTTT
y F BBITTAS: BBITTAS:
\lSpperary. Eliogarty, Thurles (O.S. 85, 41).—
BBITTASBOAD :
J
rtr^
*
^
"
v
' BBITTASBOAD :
J
Durlas or Derlas Castle (i.e. Thorles) was built before 1214, and belonged
to Theobald Walter, the first Pincerna.79 Two miles to the north of the
town, near the Suir, in the townland of Brittas, is Brittas Castle, a
modern edifice on the plan of the early Norman castles.80 A bretesche
here would guard the ford in the direction of Ikerrin, where the native
chieftain, O'Meagher, was left in possession.11 Two ring forts are marked
in this townland. The townland of Brittasroad, 'the road to the
bretesohe,' lies between Brittas and Thurles, and is now inoluded in the
Thurles township. p
BBITTAS : Tipperary, Iffa and Offa East, KHmurry (O.S. 78).—About
four miles from Carrick-on-Suir in the direction of Slieve-na-man. Carriok-on-Suir was founded by Griffin, brother of Baymond le Gros, and BUILDING
IN IRELAND 1906 488 was hence called Carrickmagrimn." In 1242 Matthew FitzGriffin
obtained a grant of a fair in his manor of Karrec.83 was hence called Carrickmagrimn." In 1242 Matthew FitzGriffin
obtained a grant of a fair in his manor of Karrec.83 was hence called Carrickmagrimn." In 1242 Matthew FitzGriffin
obtained a grant of a fair in his manor of Karrec.83 g
BBITTAS: Limerick, Clanvnlliam, Caherconlish (O.S. 14, 16).—This
district appears to have belonged to William de Burgh previously to John's
reign. The Burkes had castles at Oastleconnell and Oaherconlish from
early in the thirteenth century,64 and the barony received its name from the
Clanwilliam branch of the family. To this family belong the lords of Castle-
connell and Brittas. Brittas townland is about two and a half miles to the
east of Caherconlish, and the ruins of a stone castle are still to be seen
there on the banks of the Mulkear River, apparently guarding the approach,
from the mountainous region south of Slievefelim. In the Pipe Boll
(Ireland), 17 Ed. I, no. 20, lOi. was allowed for a britagium at Carkenlys
(Caherconlish), in Limerick; but, as already observed, this was probably
a bretesche in the later signification of a wooden parapet or tower M an
adjunct to a stone castle. There is or was a modern villa called Ballybrittas three miles from
Limerick, on the road to Broadford, in county Clare. BBITTAS: This probably
marks the site of a bretesche subsidiary to Limerick Castle, to guard the
approach from the pass of Glenomra.84 Limerick Castle is -said to have
been built by John and the honour of Limerick was granted to William
de Braose in 12OO.M » CJ>J. TOL L no. 2680.
" For a detailed account of the occupation of Connaught by the Anglo-Normans
see paper by Mi. H. T. Knoi, Journ. R.SAJ.
1902, pp. 132 and 398.
M • Fiants of Blii.' nos. 969 and 3463.
•» Printed Inquis^ Fermanagh, no. 3 Car. IL
- Journ. R.8.A.I. 1908, p. 179.
" Printed InquiB^ Antrim, no. 143 Car. L
" CJ)J. voL i. nos. 667,1871, 1468.
- Dymmok'g ' Treatise of Ireland' (1599), published in I-4.S. Tracts, ii. p. 26. OONNAUGHT. BBITTAS : Mayo, Kilmaine, KUcommon (O.S. Ill, 119).—The barony
of Kilmaine corresponds to the Irish territory known as Conmaicne Guile
Toladh.87 It would seem that no permanent settlement was made by
the English, in this part of Connaught at any rate, until after the treaty
of Windsor with the O'Conors waa finally torn up in 1227, and the whole
of Connaught granted to Richard de Burgb, saving to the king the five
best cantreds near the castle of Athlone.83 Richard de Burgh built &
castle at Bongalvy (Galway) in 1282,M and Adam de Staunton Another
at Dunamon, on the north-east border of county Galway. These, however,
were demolished next year, and down to 1287 there was nothing but fighting
and turmoil in Connaught. In that year Maurice FiteGerald made,
peace with Felim O'Conor, and the annals contain the entry,' The barons
of Ireland went to Connaught and commenced erecting castles there-' *°
In the following year (1288), we are told, castles were erected in Muintir
Morchadha (barony of Clare, county Galway), in Conmsione Cmle
(barony of Kilmaine, co. Mayo), and in Carra (the barony adjoining Kil-
maine on the north) by the barons aforesaid.91
Maurice FitzGerald, the y F VOL. XH. NO. T.TTTTTT MOTE AND BRETESCHE 484 July justiciary, was one of Richard de Burgh's principal feoffees, and the dis-
trict of Gonmaicne Guile was among those held by him. In 1244 he
obtained a grant of free chase and warren in ' Conmakonekule.'9> He is
said to have built a castle at Ballinrobe, and was probably the founder of
a house of Augustinian hermits there.93 Felim O'Conor is called the
' gossip' of Maurice FitzGerald, and for several years there was com-
parative peace in Connaught. Felim assisted Henry III at Gannoc
(Degannwy), in Wales, in 1245. It seems probable that the bretesche near Boundfort, in Kilcommon,
was erected by Maurice FitzGerald. BALLYBBIT : Galway, Galway, St. Nicholas (O.S. 82).—We have, I
think, here, as in the case of Ballybritt near Boscrea, a shortened form
of Baile an Britaigh. Indeed, in the ' Fiants of Elizabeth' the name
appears as Ballynbrytty and Ballynbrittie.94 The castle of Bungalvy
(Galway) was erected by Richard de Burgh in 1282, perhaps on the site
of a pre-Nonnan castle the erection of which is recorded in 1124. There
are remains of a stone castle at Ballybrit n. THE MOTE. There are forty-eight townland names involving the word mote
or moat. Of these twenty-three are in Leinster, nine in Munater,
twelve in Connaught, and four in Ulster. A ' moat' is shown on
the Ordnance Survey map in about twenty cases, and perhaps in
some more, but in the absence of lettering the indications given
on the map are not always clear. In six cases, where there is no
'moat' marked, there is a roughly rectilinear fort shown, and
these, I suspect, were of Anglo-Norman construction. The distri-
b'ution of these mote townlands is not unlike that of the Brittas
townlands, except that there are more mote names than Brittas
names in Galway and Mayo. They are found in districts occupied
by English invaders in the twelfth and early part of the thirteenth
centuries, and nowhere else. The word mote (French motte, L.L. viota), like the word brittas,
is not native Irish. It was clearly introduced by the Normans.100
' Motte ' names, it may be noted, are even more common in France
than bretesche names. In Ireland, at first at any rate, the word
mote was probably applied only to mounds on which the early settlers
erected their bretesches. It does not follow that they always threw
up these motes for the purpose. Whenever they found an already
existing mound—whether sepulchral, defensive, or otherwise—in a
suitable position they would naturally utilise it and shape it to
their requirements. It would then be called a'mote.'
This may
be what happened at Slane and Downpatrick, and other places,
where it is believed there were great pre-Norman mounds. Into the
question of the existence of these pre-Norman mounda in any parti-
cular places I do not propose to enter at present. Whichever view
be taken my argument that the mote and the bretesche townland
names indicate the type of the early Norman fortresses in Ireland,
and the positions of some of them, remains the same. I need
merely observe that in pre-Norman times these artificial mounds
appear to have been denoted by names beginning with dun, liss,
drum, knock, knockan, ard, &c, and, when sepulchral, tulach,
dumha, fert, &c., but they were certainly not called by any form of
the name mote. There is, however, some direct evidence that the Normans
actually erected motes in Ireland, which must be noticed. "• Here I can quote 0'Donovan's opinion and Dr. Joyce's. See the litter's Irish
Names of Places, i. 291. ULSTER. MtrLLYBBiTT: Fermanagh, Tirkennedy, Cleenxsh (0.8. 27).—This
same appears in an inquisition of 1662 as Mullebrillace,98 which looks
like a misprint for Mullebrittace. There is a ring fort, marked in the
village of Lisbellaw, in the townland, also elsewhere in the townland a
email circular plantation which may be a mote. It is near the road to
Maguire's Bridge. In 1189 an English army invaded Fermanagh, and
O'Mulrony, its chieftain, was slain. Maurice FitzGerald (the justiciary)
appears to have had an early grant of Fermanagh," and in 1211 castles
were built at Clones, near the eastern border, and at Caol Uisge, near the
western border of the territory. BBITISH : Antrim, Masserune Lower, KUlead (O.S. 64, 66).—This
seems to be the place called Ballebrittas in an inquisition of Charles I.97
It is about five miles south of Antrim, where a castle was erected pro-
bably by John de Courcy. At any rate the castle of Antrim was in
-existence and in the king's hands in 1216 and subsequently. In 1226 it
-was restored temporarily to Hugh de Lacy the younger. The bailiwick
-of Antrim appears to have then been the most lucrative in English
Ulster.9* Immediately to the south of this bretesche lay Eilultagh, ' a safe
boggy and woody country upon Logh Eaugh,' and adjoining it on the
south-east Kilwarlin, a similar fastness of bog and wood.91 There is no
fort marked in the townland, but a ' moat' is marked in the adjoining
townland of Dungonnell. 1906 435 BUILDING
IN IRELAND n. THE MOTE. In
addition to the statements in the Song of Dermot, already referred
to, as to the erection of motes at Trim and at Slane, and the record
as to the mota and britagium at Eoscrea, and the account of the
building of the first castle at Meelick, there is a direct reference, MOTE AND BRETESCHE July 436 hitherto unnoticed, to a Norman mote erected before 1231 in the
deforestation charter of Richard Mareschal. Tn that charter the
boundary of the forest of Ros is defined in one place to run from a
certain rath usque ad- viotani quavi WiUelinus Ace levavit sit]>er
aquam de Bruncuinri.m
This was in the county Wexford, near the
northern boundary of the present parish of Ross. There are some cases where stone castles, or at least stone walls,
appear to have been built on the top of motes. Mr. Westropp
mentions the motes of Ardnurcher, Shanid,
Knockgraffan,
Kilfeakle, Dunohill, Durrow, Clones, Louth, Killany, Faughart, and
Ardee, as bearing the remains of masonry, and the list might, I
think, be extended.105 But it is obvious that unless long erected
and consolidated a mote would form a very insecure foundation for
a stone castle. Probably in these cases the masonry replaced a
destroyed or decayed bretesche. At any rate it seems probable that
when it became customary to build stone castles in Ireland the mote
in the sense of a mound was generally dispensed with, and, perhaps
about the same time, the name mote or moat became commonly
applied to the ditch, especially a wet ditch, which still surrounded the
castle.1"3 It is probable that some of the moat names, especially
some of those in Galway and Mayo, refer to moats in this sense,
and that the rectilinear forts there and elsewhere noted in the
mote townlands mark the sites of stone or wooden towers erected
within them. I have ascertained, however, that some of these
Connaught mote townlands contain low fortified mounds, and local
examination may disclose similar mounds in others. A carefully compiled and classified list of motes and other
defensive earthworks in Ireland is a great desideratum. Mr. Westropp has done much to increase our knowledge in this respect,
but there is much more to be done, as he would be the first to
acknowledge. '" Register of St. Mary's Abbey, Dunbrothy, published' with the Chartulary of
St. Mary's Abbey, Dublin, B.S. ii. 155. I have made some search, but up to the
present in vain, for this mote. It ma; have been on the site of the castle at Palace, and
cannot, I thint, have been far off. The word levait seems applicable only to a mound.
'« As, for instance, the mote at St. Mullins, co. Carlow, which has the stone
foundations of a square structure on its summit; and at its base a large rectangular
bawn can clearly be traced.
1M With the double meaning of the word viote or moat may be compared the
similar ambiguity in the words dyke, ditch, digtic, i'c, but I think the transferred
meaning in the case of mote names may have been facilitated by the use of the word
to designate the whole fortress without any special connotation. This use seems to
be attested by the place names. Ballymote is thus virtually equivalent to Caatletown.
The Four Masters (a. 1598, 1599, pp. 2082, 2114) spenk of Mountgarrett Castle,
near New Boss, as ' Mota Guirett,' though it has no sign of either mound or ditch about
it. It was probably built in the beginning of the fifteenth century (Hore's History
of Wexford, i. 180). 1M With the double meaning of the word viote or moat may be compared the
similar ambiguity in the words dyke, ditch, digtic, i'c, but I think the transferred
meaning in the case of mote names may have been facilitated by the use of the word
to designate the whole fortress without any special connotation. This use seems to
be attested by the place names. Ballymote is thus virtually equivalent to Caatletown.
The Four Masters (a. 1598, 1599, pp. 2082, 2114) spenk of Mountgarrett Castle,
near New Boss, as ' Mota Guirett,' though it has no sign of either mound or ditch about
it. It was probably built in the beginning of the fifteenth century (Hore's History
of Wexford, i. 180). ,
,
pp
y
'« As, for instance, the mote at St. Mullins, co. Carlow, which has the stone
foundations of a square structure on its summit; and at its base a large rectangular
bawn can clearly be traced.
1M '" Register of St. Mary's Abbey, Dunbrothy, published' with the Chartulary of
St. Mary's Abbey, Dublin, B.S. ii. 155. I have made some search, but up to the
present in vain, for this mote. It ma; have been on the site of the castle at Palace, and
cannot, I thint, have been far off. The word levait seems applicable only to a mound. '" Register of St. Mary's Abbey, Dunbrothy, published' with the Chartulary of
St. Mary's Abbey, Dublin, B.S. ii. 155. I have made some search, but up to the
present in vain, for this mote. It ma; have been on the site of the castle at Palace, and
cannot, I thint, have been far off. The word levait seems applicable only to a mound.
'« As, for instance, the mote at St. Mullins, co. Carlow, which has the stone
foundations of a square structure on its summit; and at its base a large rectangular
bawn can clearly be traced. n. THE MOTE. The scheme for recording ancient earthworks and
fortified inclosures proposed by the Congress of Archaeological
Societies, if and when accomplished, will go far to supply the want. BUILDING
IN IRELAND 487 1906 For my part I have been much struck by the number of cases in
which a mote has been found at or close to the probable sites of
castles built before the close of John's reign. Mr. Westropp
mentions eighteen of these out of some sixty castles recorded to
have been built in the period.104 I think he has shown that
probably some of these motes were pre-Norman, but their fre-
quent occurrence at or near the castle sites requires explanation,
and seems to be best explained by supposing that in most cases, at
any rate, they were either thrown up or at least utilised by the
Normans for their first fortresses in the manner suggested in this
paper. Existing remains of stone castles near to but not on the
motes may well be of later construction. Whenever a new castle
was built to replace one that was obsolete the nearest suitable site
would, for obvious reasons, be selected. Again, when we examine Mr. Westropp's list of ' Chief Motes of
Ireland'1U5 we find that the large majority, at any rate, are in districts
known to have been occupied by the English before the close of John's
reign, and many of these places can be shown to have been capita
manerii even where we have no actual record of the building of an
early fortress of any kind. In this connexion it must be remem-
bered that documentary evidence prior to John's reign is fragmentary
in the extreme. Mr. Westropp's list is expressly confined to ' chief '
motes, so I do not say that it is incomplete. From my own very
limited observation, however, I could add some instructive examples. Thus at Glascarrig, in the county Wexford, a place granted by
Strongbow to Raymond le Gros,lwi there is a mote (somewhat larger
than the so-called mote at Ardamine, a few miles to the north)
surrounded by a ditch and low rampart and connected with an
irregular inclosure. Viewed as mote names, however, Mr. West-
ropp's list seems redundant. 104 Jotirn. R.SUJ. 1904, p. 845.
The list of motes near early attested castles is
incomplete.
There is * large mote surrounded by a fosse at Dungarvan and another
at Tipperaghny (Lewis); and Castlemore, in the barony of Forth, co. Carlow, can be
shown from the charters in the register of St. Thomas, Dublin, to be the site of
Baymond's castle of Fotheret 0'Nolan. , p
j f
,
"' The earthworks at Ballyknockan, identified by O'Donovan with the Dinn High
of Irish tradition, do not indeed constitute a mote in the usual acceptation of the term.
Situated on the steep slopes of the river valley, the fort looks something like a mote
from the lower or river side, but its summit is hardly, if at all, higher than the level
of the adjoining land on the upper side. '•» Journ. R.S~i.I. 1904, p. 342.
'•* Scnuj of Dermot, 1. 8068. y
'•» Journ. R.S~i.I. 1904, p. 342. '•* Scnuj of Dermot, 1. 8068. 1M Song of Dermot, 11.3144-5. The description of the mote giyen aboye ia from a
paper on the town of Navan by Mr. J. H. Moore, Journ. R.S-A.J. 1893, p. 57. n. THE MOTE. I doubt if all these earthworks are
even now called ' motes,' except, perhaps, loosely by the ' learned
classes.' When I was close to Ballyknockan, in Carlow, I could get
no one to tell me where the ' mote' was, but when I asked for the
' old fort' I was understood at once.107 The mound at Ardamine,
in the county Wexford, moreover, does not come within Mr. West-
ropp's definition of a mote. It shows no sign of ' rings or fosses ' MOTE AND BRETESCHE 488 July about it, and has all the outward appearance of being an unaltered
sepulchral mound. p
The following list is not a list of motes, but of mote names
attached to townlands. Its importance is due to the fact that the
townland names are in general very old, and to the probability—
supported, I think, by the distribution and positions of the mote
names—that the name mote, itself of Anglo-Norman origin, was at
first only given to mounds on which the Normans erected bretesches,
or, in some few cases, stone castles. Afterwards, as I have said,
when the mound was dispensed with, the name mote or moat came
to be applied to the ditch which surrounded the castle. In modern
times, when the origin of the name and its earlier restricted use
have been forgotten, it is often applied, especially by educated
people, to any artificial mound, without regard to its origin or the
uses to which it has been put; but I do not think that this indis-
criminate employment of the word has affected to any great
extent, if at all, the townland mote names. At the same time it
suggests caution, and the mote names cannot be considered so
sure a guide to early Norman sites as the bretesche names. More-
over it must not, of course, be supposed that every mote erected or
utilised for a Norman fortress has impressed the name on the
townland ; but a full examination of the earthworks designated by
authentic mote names may afford criteria by which we shall be
enabled to distinguish mounds which have been the sites of Norman
fortresses from mounds which have never been so used. at Simon Fraser University on June 6, 2015
http://ehr.oxfordjournals.org/
Downloaded from MOAT TOWN : Meath, Lime, Kildalky (O.S. 26).—The barony of Lune LEINSTEB. BALLYMOAT : Wicklow, Newcastle, Glenealy (O.S. 24, 25, 80).—This
townland includes Ballymoat House and the village of Glenealy. It is
probably the Ballenmote mentioned along with Brittas in the Printed
Inquis., Wicklow, nos. 8 4 5 Jac. L The juxtaposition of the names,
which may refer to the same mote and bretesche, is significant y
g
Mr»ATmT,T.: Meath, Navan Lower, Navan (O.S. 25).—Tina townland
includes Navan Moat, a natural frill surmounted by a mote. This bill
' rises 45 feet above the road at its base. The mote is 26 feet high, oval
on plan, the diameters of the base being 185 and 122 feet, and of the top
52 feet. On the north-west is a lone-shaped platform 7 or 8 feet high
and 90 feet long, by 80 feet greatest breadth. A tail of this platform
comes round the west side of the mote, nearly 100 feet further, only
6 feet wide on top.1 This may have been the site of a bretesche erected
by Jocelin de Nangle, to whom ' le Novan ' and the land of Ardbraccan
were given by Hugh de Lacy.108 MOAT TOWN : Meath, Lime, Kildalky (O.S. 26).—The barony of Lune BUILDING IN IRELAND 1906 489 was granted by Hngh de Lacy to William de Moset or Meset or Misset.10*
Moat-town House is marked on the map. p
MOAT : Meath, Fore, Kiileagh (O.S. 8). p
MOAT : Meath, Fore, Kiileagh (O.S. 8). MOAT : Meath, Kells Lower, EHbeg (O.S. 5, 11). MOAT: Meath, Kells Upper, Dulane (O.S. 10).—'Moat' marked,
also 'Moat House." A castle was built at Kells in 1176-8, and Meath
generally was plurimum incasUllata in Hugh de Lacy's time.110 MOAT : Meath, Moyfenrath Lower, Rathmolyon (O.S. 42).—I should
like to examine these four mote townlands in Meath in which no mote
is marked on the map before forming any opinion as to what exactly was
referred to by the name. y
MOATAVALLT : Longford, Ardagh, Street (O.S. 15).—There is perhaps
a mote in the grounds of Moatavally House. The name probably means
the mote of the bealach or ' street.' It is called Motenvally in the Stuart
Inquisitions. q
MOAT-FAREBLL : Longford, Oranard, Glonbrony (O.S. 14,15).—Moat
and castle marked, the castle apparently on the mote. ' Mota' was granted
by Elizabeth to W. O'Ferrall Bane, chief and captain of his nation.111 MOATFTRTIT) : Longford, Oranard, Oranard (O.S. g
f
,
1U Four Masters, 1192. "• Song of Dermot, L 8159, note.
111 ' FiantB of Eliz.' nos. 5063, 5107.
•" Song of Dermot, 1L 8154, and note.
1U Four Masters, 1192.
"• Song of Dermot, 11. 8096-9. LEINSTEB. 10).—This is the
mote in the town of Oranard, said to be the largest simple mote in
Ireland. It was perhaps the site of a bretesche erected by Bichard Tuit
in 1200 ' as a stronghold against O'Reilly in South Breifne.'112 King John
stopped on 12 August 1210: apud Orenard, castrum Bicardi de Thuit. pp
g
BALLTMOAT : Longford, Ardagh, Ardagh (O.S. 14,19, 20).—Geoffrey
de Cons tan tine had ' fifteen knights' fees in the land of Conemake (Long-
ford),' near Kilbixi and beyond the river Inny. These may have included
this townland.11' MOATB-GRANOGE : Westmeath, Clonlonan, KilcUagh (O.S. 80, 86).—
This is the large mote in the town of Moate, which may have been used
for a bretesche on the frontier of Meath. For the legend concerning the. name see C. Otway's Tour in Connaught, p. 55, but perhaps it only
means the' mote of the hedgehog ' (graineog). The neighbouring cantred
of Ardnurcher was granted by Hugh de Lacy to MeUer FitzHenry,lu
and a castle was built here in 1192.115 There are remains of a stone
castle on the mote at Ardnurcher. MOATB-GRANOGE : Westmeath, Clonlonan, KilcUagh (O.S. 80, 86).—
This is the large mote in the town of Moate, which may have been used
for a bretesche on the frontier of Meath. For the legend concerning the. name see C. Otway's Tour in Connaught, p. 55, but perhaps it only
means the' mote of the hedgehog ' (graineog). The neighbouring cantred
of Ardnurcher was granted by Hugh de Lacy to MeUer FitzHenry,lu
and a castle was built here in 1192.115 There are remains of a stone
castle on the mote at Ardnurcher. MOATAVANKT : Kildare, Kilkea andMoonc, Castledermot (O.S. 88}.—
' Glassavanny Moat' is marked in the townland. The name seems to
involve the word beann, often applied to a house or fort in the sense of
gable, pinnacle, or turret. This was in ' Omorethi,' granted by Strong-
bow to Walter de Biddlesford."6
There is also a mote at Kilkea Castle. MOAT COMMONS : Kildare, Glane, Olane (0.8.14).—Mote near Clane
Bridge. This was in ' Offelan,1 granted by Strongbow to Maurice
FitzGerald.117 MOAT COMMONS : Kildare, Glane, Olane (0.8.14).—Mote near Clane
Bridge. This was in ' Offelan,1 granted by Strongbow to Maurice
FitzGerald.117 MOATSTOWN : Kildare, Narragh and Beban West, Churchtovm (O.S. 84, 85).—Small mote in the townland by the river, opposite Tyrrellstown. "• CJ)J. voL i. nos. 673, 1392.
"• Printed Inquis., Queen's Co., no. 16 Car. L
•• CMari. of St. Mary's, Dublin, iL 406.
111 Jour*. R.S^iJ. 1874-6, p. 486.
IM 8ong of Dtrmot, H. 8114-7 and note
'» Ibid. L 274a
'" Ibid. IL 3810-36 and 8040 tt ug.
"> Bee deed (translated), Journ. R.S-AJ. 1864-6, p. 147, note. LEINSTEB. "• Song of Dermot, L 8159, note. 111 "• Giraldna, v. 355. '" Four Masters, 1199, note i •" Song of Dermot, 1L 8154, and note. '" Ibid. 1. 8188. 1U Four Masters, 1192. •" Ibid. 11. 3086-91. "• Song of Dermot, 11. 8096-9. MOTE AND BRETESCHE 440 July This district, innimUng Beban Castle, where there is ' a quadrilateral
entrenchment with a high conical mound at its western extremity'
(Lewis), was, I believe, granted to the father of Richard de Si. Michael
by Strongbow.118 This district, innimUng Beban Castle, where there is ' a quadrilateral
entrenchment with a high conical mound at its western extremity'
(Lewis), was, I believe, granted to the father of Richard de Si. Michael
by Strongbow.118 y
g
MOAT : Queen's County, GuUenagh, Disertgallen (O.S. 80).—There is
& large mote and site of ' Moat Castle' marked in the townland, About
two miles east of Ballynakill. * It was on the frontier between Ossory
(Kilkenny) and Leix. It is called ' le Mpaie' in the Stuart inquisitions.119 MOAT ; Kilkenny, Crannagh, Freshford (O.S. 18).—Mote in the town-
land near Freshford. Two knights' fees in Acheteyr (Le. Achadh-ur, the
Irish name of Freshford) were held by John d'Evreux at the time of the
Leinster partition.110 p
MOATPABK: Kilkenny, Fossodinin, Donoghmore (O.S. 4, 6).—This
townland is on the Nore near Ballyragget. I do not find a mote marked
on the map, but I presume the name refer&jo the Moate hill described m
as being on the Nore about a quarter of a mile from Ballyragget, about
eighty feet high, with a deep fosse under it. BAira«»Yra™' BAira«»Yra™ '} w*tf°rd> ScUlaghkeen S., Ballyhuskard (O.S. 20). —There is a conspicuous mote on the former townland about four miles
east of Ennisoorthy. I cannot say anything about the other. The
barony of Ballaghkeen corresponds to the Irish tribal territory of southern
Offelimy, which was granted by Strongbow to Gilbert de Boisrohard.11* MOTABEG (or SALVTLLB) : Wexford, Ballaghkeen S., Templeshannon
(O.S. 26).—A large mote with deep fosse (capable of being flooded) and
rampart one mile south of Enniscorthy. "• Girmldtu, TOL v. p. 848.
"• Four MasUrt, 1193.
«• CJ> J. nd. 1 no. 187.
m Boger Howden, TOL it pp. 188-5.
"• OJDJ. toL L no. 576.
•" Joitrn. B.SJLJ. 1901-*.
•» GJ)~L voL I no. 1518.
« Ibid. no. MS. LEINSTEB. The Duffry, a district which
extended from the mountains to Enniscorthy, was given by Strongbow to
Robert de Quenoy,123 and passed with his daughter Maud to Philip de
Prendergast.'*4 This mote may have been the site of the first fortress
here, before Philip de Prendergaat obtained Enniscorthy from the bishop
of Ferns in the year 1227.124 y
MOTABOWBB : Wexford, Qorey, Carnew (O.S. 5, 6).—In the Inquis. P. M. on Aylmer de Valence, 17th Ed. II, no. 75, Reginald de Nyvel is
mentioned as holding a quarter of a knight's fee in Balyconewey (Carnew)
and an eighth in Gory (Gorey), then valued nil as having been destroyed
by the Irian. The name, according to Dr. Joyce, means ' deaf moak'(?)
MoATALtrsHA: Carlow, Carlow, Grangeford (O.S. 8).—There is
perhaps a small mote indicated in the grounds of Moatalusha House. The name would seem to mean the' mote of the quicken tree' (Mota hiise). Oastlemore Mote, which was, I think, the site of Raymond le Gros's castle
of Fotheret O'Nolan, is only about a mile distant. There are foundations
of stone walls on a square platform at the base of this mote. BUILDING IN IRELAND 441 1906 MTTN8TBB. BALLYMOT : Cork, Eerryeurrihy, Monkstown (O.S. 87).—This was
probably included in Milo de Oogan's four oantreds to the west of the
town of Cork.116 A bretesche here would guard the approach by water to
the town. MOATQUABTEE : Tipperary, Clanwilliam, Kilfeakle (0.8. 69, 60, 67). —Kilfeakle mote; a «astle was erected here in 1192.'" The barony of
Glanwilliam appears to have been in William de Burgh's hands in the
beginning of John's reign and was probably granted to him long before. Hi
tl
fl Kill f
l '
t
d t hi
i
1208 1 * pp
y,
,
f
(
,
,
)
—Kilfeakle mote; a «astle was erected here in 1192.'" The barony of
Glanwilliam appears to have been in William de Burgh's hands in the
beginning of John's reign and was probably granted to him long before. His castle ofl Killefecle' was restored to him in 1208.1-* MoATABUiiCAirK: Tipperary, Glanwilliam, Templenoe (O'.S. 69.)—The
name may have reference to the shape of the mote, like a puff-ball or
mushroom (bolgdn). (
g
)
MOATQUABTKB : Tipperary, ClanwiUiam, Donohill (O.S. 61, 69).—
Donohill mote, on which the remains of a castle are still to be seen. MOTA : Tipperary, Qrmond Lower, Kilbarron (O.S. 6, fl).—Mote
House marked near Lough Berg. This was in the territory of Theobald
FitiWalter, the first Pincerna. MOATQUAETHB : Tipperary, Ikerrin, Bathnaveoge (O.S. 16, 22).—
About 4 miles south of Boscrea. In Theobald Fitz Walter's territory. y
MOAT : Waterford, Deoies within Drum, Bingagonagh (O.S. 86).—
There is a 'moat' marked in-the townland, but I am informed by Mr. y
MOAT : Waterford, Deoies within Drum, Bingagonagh (O.S. 86).—
There is a 'moat' marked in-the townland, but I am informed by Mr. Beary, borough surveyor, Duagarvan, that it is- quite a low mound on a
natural rise of ground and that ' its base is level with the field;' It can
hardly, therefore, be the site of a bretesche, unless the fosse has been
obliterated. At the Council of Oxford in 1177 Henry II granted the
custody of Waterford to Robert le Poer, and made all the land between
the town and the Blackwater appurtenant to the services of Waterford.11*
There is a large fortified mote at Dungarvan, and a castle was in existence
here in 1216, when its custody was given to Thomas FitzAntbony.130 y
g
y
BALLTMOAT : Waterford, Middlethird, Beuk (0.S-. MTTN8TBB. 1G, 17).—I am
told of a mote (unmarked) in this townland and the next. BALLYMOAT : Waterford, Coshbride, Kilwatermoy {O.S. 28, 89). CONNAUGHT. The apparent absence of motes (in the sense of high mounds) in
most of the mote townlands in Connaught, coupled with the preeenoe
in many cases of rectilinear forts, makes it probable that the mote names
here sometimes refer to ' moats' in the later sense of ditches, and this
agrees with the later dates when the lands in question appear to have
been first permanently occupied. Mr.H. T.Enox, who has made a study of
the Anglo-Norman settlement in Connaught,1" says that the grant of Con-
naught to Biohard de Burgh-in 1228 (or rather 1227),1*1saving five canireds
to the king, was the foundation of this settlement. Nevertheless there
were many partial settlements much earlier, as Mr. Knox indeed elsewhere
notices. Thus in 1216 this same Bichard de Burgh was granted all the
land of Connaught which William his father held,1** and many individual 442 MOTE AND BRETESCHE July settlers can be traced from even before the close of the twelfth century,
some of whom we shall mention. Many of the following districts were
recovered by the Irish after the murder of William, earl of Ulster, in
1388. BALLYMOTB: Sligo, Corran, Emlaghfad (O.S. 88).—The castle at
the town of Ballymote, the remains of which are still to be seen, perhaps
occupies the site of the mote. It was began by Richard, the Bed
Earl, in 1800.1" I find it stated, however, that' near Ballymote there
are some good examples of forts (perhaps tumuli) ramparted and
moated.'1M Gerald de Prendergast was probably the original grantee of
the barony.136 BALLYMOTB: Sligo, Corran, Emlaghfad (O.S. 88).—The castle at
the town of Ballymote, the remains of which are still to be seen, perhaps
occupies the site of the mote. It was began by Richard, the Bed
Earl, in 1800.1" I find it stated, however, that' near Ballymote there
are some good examples of forts (perhaps tumuli) ramparted and
moated.'1M Gerald de Prendergast was probably the original grantee of
the barony.136 MOAT: Galway, Ballymoe, Kilbegnet (O.S. 19).—Kilbegnet was in
Tirmany, a cantred granted to Geoffrey de Constentein in 1201."7 It
was afterwards included in one of the king's five cantreds. A carious
quadrilateral fort with outer (incomplete) fosses is marked on the map. BALLYMOAT : Galway, Dunmore, Tuam (O.S. 29, 48, 44).—Meyler de
Bermingham held the barony of Dnnmore from Richard de Burgh.1**
A square fort is marked on the map. "* Four Masters, 1300, where it is called the castle of Ath-Cliath an Chorainn, Le.
of Ballymote.
Journ. B.S-AJ. 1887-8, p. 268.
'« Ibid. 1903, p. 72.
117 CJ)J. voL i. no. 183.
•» Journ. B.SJLJ. 1901, p. 867.
Tribes of Hy Many, p. 128.
See tract printed in Tribes of Hy Many, pp. 188-42.
My Many, p. 151.
"» CJ)J. vol. L noa. 853, 537. CONNAUGHT. MOAT : Galway, Txaquin, Moylougk (O.S. 45).—Moat Hill Lodge is
marked. ' Kelly of Moot or Moat' is mentioned in the pedigrees of the
O'Eellys.1*9
Perhaps this townland or the next is intended. MOAT : Galway, Kilconnell, Aughrim (O.S. 87).—This was in Omany,
one of the king's cantreds. A square fort, called Babbit Fort, is marked. MOAT : Galway, Longford, Killimorbologue (O.S. 117).—A mote
marked by the river opposite Flower Hill House. The barony of Long-
ford represents the territory of Sil Anmchadha. William de Burgh, as
we have seen, built the first castle at Meelick in 1208. The native
chieftains, the O'Maddens, seem to have been very loyal to the De
Burghs.140 g
MOATY : Galway, Longford, Clonfert (O.S. 100, 108).—A square fort
is marked in the townland, which is spelt ' mota' in a grant of the year
1677."1 g
MOATY : Galway, Longford, Clonfert (O.S. 100, 108).—A square fort
is marked in the townland, which is spelt ' mota' in a grant of the year
1677."1 MOATY: Galway, Longford, Ktitormer (O.S. 99).—A mote is marked
close to Newtown demesne. MOTE DEMESNE : Boscommon, Athlone, KUmeane (0.8. 40, 41, 42).—
This district was granted to John Marshall in 1207, and taken up again
for the king of Connaught in 1214-6.ut MOAT : Mayo, Costello, Annagh (O.S. 102, 108).—There is no mote
marked on the map, but I am informed by Sergeant Lyons, B.I.C., of
Ballyhaunis, that ' Annagh Moat,' in the Moat townland, is ' more a
fortified esker than a mote.' It is oval in shape, 258 feet by 167. CONNAUGHT. It
is surrounded by a deep fosse about 16 feet wide near the bottom and
capable of being flooded from a neighbouring brook, and ' the central BUILDING IN IRELAND 443 1906 elevation rises about twelve feet above the inner edge of the fosse—a
low hog-back, in fact.'
This district seems to have belonged to John
FitzThomas of Desmond at his death in 1261, under the name of
Kerglochnarn.143 The barony of Costello, however, got its name from
Gilbert de Angulo or Nangle, who held lands in Connaught at the be-
ginning of John's reignUi and was called by the Irish MacOsdealv,14*
which, I believe, was an attempt to render ' Son of Jocelin.'us The
lands of 'Anaghe' are inoluded in the surrender of 1586 by 'Shean
McCostello of Castlemore in the barony of Bealahawnish' to Queen
Elizabeth.147 MOAT : Mayo, Carra, Ballintubber (0.8. 89). MOAT : Mayo, Carra, Ballintubber (0.8. 89). MOAT : Mayo, Glanmorris, Balla (O.S. 90).—These baronies were in-
cluded in Richard de Burgh's land, and were probably settled up not long
after the grant to him in 1227. They appear under the names of Ker
and Crigfertur respectively in the inquisition on the lands of William de
Burgh in 1838.148 Castles were erected in Carra in 1288. MOAT : Mayo, Glanmorris, Balla (O.S. 90).—These baronies were in-
cluded in Richard de Burgh's land, and were probably settled up not long
after the grant to him in 1227. They appear under the names of Ker
and Crigfertur respectively in the inquisition on the lands of William de
Burgh in 1838.148 Castles were erected in Carra in 1288. g
I find no mote marked in any of these Moat townlands in Mayo, but
if the mote was not a mound of a considerable height it would not be
marked on the Ordnance map, as we have seen in the case of Annagh
Moat. 1U CD./, vol. ii. p. 429; Four Masters, 1224, note n.
'" C.D.I. TOI. i. nos. 311, 354.
1U Four Masters, 1193. He seems to have served as a sort ol mercenary under
Cathal Crovderg, ibid. 1195.
'- Song of Dermot, L 8145 and note.
'" ' Fiants of Eli*.' 489a
1U Journ. R.S-A.I. 1902, pp. 397 and 398.
"• Four Masters, 1177.
'•• Expugn. Hib. bk. ii. cap. xvii.
»• Four Masters, 1213. ,
»• Four Masters, 1213. '" Lewis.
'" Journ. R.SA.I. 1905, p. 262.
'" CJD.I. vol. i. no. 92.
"» Ajite, vol. xi. (1905), p. 83.
IM Journ. R.SA.I.
1898, p. 155, and 1904, p. 354. ULSTER BALLTMOTE : Antrim,
Massarene Upper, Olmavy
(0.8. 69).—
A polygonal fort is marked three or four miles south of the ' British'
townland in Massarene Lower. BALLYMOTE LOWEB, MIDDLE, AND UPPEB : Down, Lecale, Down
(O.S. 87, 88).—These three townlands are together, and now join the
'demesne of Down,' which lies to the north and includes the town of
Downpatrick and the great' moat.' Probably they got their name from
it, as no mote or rectilinear fort is marked within their present boundaries. In 1177 John de Courcy plundered Dundaleathglas (Downpatrick) and
erected a castle there, which became the headquarters of all his expeditions
in Ulster.M9
The three Ballymote townlands are mentioned in Inquis.,
Down, nos. 8 Jac. I and 68 Car. I. It may be noted that De Courcy
could not have fortified even an existing mote before the attack of Cooley
MacDonlevy, the king of Ulidia (Down and Antrim), for this took place
within eight days of his arrival, and Gerald de Barri says that De Courcy
preferred to sally forth and meet his foe rather than be besieged in the
exile municipium quod in urbis angulo tenuiter erexerat. This was in
February, but when, after 24 June, he was defeated in Firli, in the
north of Antrim, he retreated ad castrum $uum.'i0 MOTALEA : Londonderry, Loughinsholin, Desertmartin (O.S. 41).—
Desertmartin is on the road from Armagh to Coleraine, where a stone
castle was built in 1213.151
Near the old church on the opposite MOTALEA : Londonderry, Loughinsholin, Desertmartin (O.S. 41).—
Desertmartin is on the road from Armagh to Coleraine, where a stone
castle was built in 1213.151
Near the old church on the opposite MOTE AND BRETESCHE BUILDING 444 July bank of a small river ' are the remains of a fort, evidently raised to
defend the pass of the river.'183 bank of a small river ' are the remains of a fort, evidently raised to
defend the pass of the river.'183 p
MOAT : Cavan, Clanmahon, Ballymachiigh (O.S. 87, 41).—This is on
the borders of Lough Sheelin, near the confines of the counties of Meath
and Longford. Since making the list printed above I have noted the following
additional townlands with mote nameB :— Since making the list printed above I have noted the following
additional townlands with mote nameB :— KILLAMOAT : Wicklow, Talbotstovm Upper, Eiltegan (O.S. 28, 88).—
Perhaps the site of one of the numerous bretesches hemming in the
mountainous district of Wicklow. KNOCKNAMOTA : Wexford,
Scarawalsh, Carneto (O.S. 6).—Near
Motabower, on the northern frontier of county Weiford. LISBAMOTA : Limerick, Connello Upper, Ballingarry (O.S. 29, 80).—
Here are the ruins of Lissamota Castle.153 The two cantreds of' Hochenil'
(i.e. Ui Conaill, now the baronies of Upper and Lower Connello) were
granted by John, when earl of Mortain, to Hamon de Valoignes.11* g
y
g
BAWNAVOTA : Cork, Kinsale, Rincurran (O.S. 112, 125).—A signifi-
cant name, meaning ' the bawn of the mote.' It probably represents an
early fortress of the De Courceys, barons of Kinsale. g
y
g
BAWNAVOTA : Cork, Kinsale, Rincurran (O.S. 112, 125).—A signifi-
cant name, meaning ' the bawn of the mote.' It probably represents an
early fortress of the De Courceys, barons of Kinsale. As further direct evidence of the erection of a wooden castle
(bretesche) in early Anglo-Norman times in Ireland I should like
to call attention to the following passage in the Irish Abridgment
of the ' Expugnatio Hibernica,' describing the landing of Raymond
le Gro8 in Ireland :— This is the place to which Raymond came, Dun Domnaill, four mile3
on the south side of Waterford. [There] he made a trench of stones
and clay, and then they wrought a wondrous work, to wit, a fortalice of
wood (caislin crainn).xi* The manuscript of the Abridgment is ascribed by the editor, Dr. "Whitley Stokes, to the fifteenth century, but the rendering of
Gerald's tenue satis ex virgis ct respite centrum crexerunt has all the
appearance of being based on genuine local memory, just as the
name Dim DomhnaiU is given, not as Gerald gives it, but in what
I had already suspected to be the correct form. I may here add
(what was unknown to Dr. Stokes) that I have already identified
Raymond's fort, called by Gerald ' Dundunnolf,' and in the Sung oj
Dermot ' Domdonuil,' ' Dondonuil,' and ' Dundounil,' with the
headland of Baginbun, on the south coast of county Wexford,
where ' the trench of stones and clay' with double rampart, about
240 yards long, may still be seen, cutting off the whole head-
land.186 GODDABD H. OEPEN. '" Lewis. '" Journ. R.SA.I. 1905, p. 262. '" CJD.I. vol. i. no. 92. "» Ajite, vol. xi. Since making the list printed above I have noted the following
additional townlands with mote nameB :— (1905), p. 83. IM Journ. R.SA.I. 1898, p. 155, and 1904, p. 354.
|
https://openalex.org/W4386545365
|
https://www.nature.com/articles/s41417-023-00664-5.pdf
|
English
| null |
Clonal dynamics limits detection of selection in tumour xenograft CRISPR/Cas9 screens
|
Cancer gene therapy
| 2,023
|
cc-by
| 16,150
|
INTRODUCTION growth and drug sensitivity are not necessarily the same in cell
culture and in tumours. To address this, tumour models are
required that are suitable for in vivo functional genomics screens. The molecular profiling of human tumours offers unprecedented
opportunities to individualise cancer therapy [1]. Detection of
oncogenic mutations in patient tumours allows treatment with
therapies that directly target the mutation, in some instances in a
tissue-agnostic approach [2]. In addition, gene expression profiles
can be used to track the emergence of resistance [3] and to
identify predictive biomarkers to optimally match drugs with
patients [4], but there is an incomplete understanding of the
genes that determine sensitivity to most anticancer agents. One
approach to remedy this is through the use of functional
genomics screens, which alter gene activity by knockdown (RNA
or CRISPR interference) or mutation (CRISPR/Cas9) using largescale
libraries, select specific phenotypes (e.g. drug sensitivity or
resistance) and then identify the gene(s) responsible [5, 6]. Tumour models for in vivo CRISPR screens can be generated
through direct mutagenesis in vivo or through in vivo transplanta-
tion of cells mutagenised in culture. The direct approach allows
spontaneous autochthonous tumour formation with preservation
of the tumour microenvironment in immunocompetent mice but
is associated with numerous technical challenges, restricting its
use to very small gRNA libraries of a few hundred gRNAs [26, 27]. Transplantable models, conversely, are more amenable to larger
gRNA libraries. Cancer cell lines transduced at scale with larger
gRNA libraries (thousands of gRNAs) can be injected into mice at
large cell numbers to ensure high representation of each gRNA at
inoculation [28–33]. However, the majority of transplantable
in vivo CRISPR screens report a dramatic loss of clonal diversity
during tumour growth due to the selection and bottleneck of
cellular evolution imposed by the transition from in vitro to in vivo
tumour growth [28, 29, 31, 32]. This loss of clonal diversity and
gRNA representation consequently limits the discovery of genes
that influence therapeutic response in these in vivo CRISPR
screens. Given these limitations, the optimisation of experimental
parameters would be beneficial when conducting in vivo screens. To our knowledge, however, experimental data in the literature on
the importance of these parameters is limited. Whole genome functional genomic screens utilising CRISPR/
Cas9 technology were first applied for evaluating genes involved
in drug sensitivity or resistance in cancer cell lines in 2014 [7–9]. 1Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand. 2Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland,
New Zealand. 3Oncology Therapeutic Area, Janssen Research and Development, Spring House, PA, USA. 4Department of Molecular Medicine and Pathology, University of
Auckland, Auckland, New Zealand. 5Department of Pharmacology and Clinical Pharmacology, University of Auckland, Auckland, New Zealand. ✉email: tw.lee@auckland.ac.nz;
s jamieson@auckland ac nz ARTICLE
OPEN
Clonal dynamics limits detection of selection in tumour
xenograft CRISPR/Cas9 screens 1,2✉, Francis W. Hunter1,2,3, Peter Tsai2,4, Cristin G. Print2,4, William R. Wilson
1,2 and Stephen M. F. W. Hunter1,2,3, Peter Tsai2,4, Cristin G. Print2,4, William R. Wilson
1,2 and Stephen M. F. Jamieson
1,2,5✉ © The Author(s) 2023 Transplantable in vivo CRISPR/Cas9 knockout screens, in which cells are edited in vitro and inoculated into mice to form tumours,
allow evaluation of gene function in a cancer model that incorporates the multicellular interactions of the tumour
microenvironment. To improve our understanding of the key parameters for success with this method, we investigated the choice
of cell line, mouse host, tumour harvesting timepoint and guide RNA (gRNA) library size. We found that high gRNA (80–95%)
representation was maintained in a HCT116 subline transduced with the GeCKOv2 whole-genome gRNA library and transplanted
into NSG mice when tumours were harvested at early (14 d) but not late time points (38–43 d). The decreased representation in
older tumours was accompanied by large increases in variance in gRNA read counts, with notable expansion of a small number of
random clones in each sample. The variable clonal dynamics resulted in a high level of ‘noise’ that limited the detection of gRNA-
based selection. Using simulated datasets derived from our experimental data, we show that considerable reductions in count
variance would be achieved with smaller library sizes. Based on our findings, we suggest a pathway to rationally design adequately
powered in vivo CRISPR screens for successful evaluation of gene function. Cancer Gene Therapy (2023) 30:1610–1623; https://doi.org/10.1038/s41417-023-00664-5 Cancer Gene Therapy Cancer Gene Therapy www.nature.com/cgt Cancer Gene Therapy (2023) 30:1610–1623; https://doi.org/10.1038/s41417-023-00664-5 Received: 31 May 2023 Revised: 8 August 2023 Accepted: 29 August 2023
Published online: 8 September 2023 Polymerase chain reaction y
We modified the original PCR protocol designed for lentiGuide-Puro
vectors [8, 28], utilising a three-stage PCR protocol to amplify the gRNA
sequences from the gRNA cassette in the gDNA in preparation for Illumina
sequencing. Herculase II Fusion DNA Polymerase (Agilent Technologies,
Santa Clara, CA) was used for all reactions. Each reaction contained 0.5 µl
DNA polymerase, 1 mM dNTP mixture, 4% DMSO and 1× Herculase II Buffer
in 50 µl volume. Between each PCR, Ampure XP beads (Beckman Coulter,
Brea, CA) were used to purify the PCR products, and the Qubit DNA-BR
assay was used to quantify products. In PCR1, 0.25 µM of forward and
reverse primer (F1 and R1 from reference. [8]) and 5 µg gDNA per 50 µl
reaction was used. Cycling parameters were an initial denaturation at 98 °C
for 5 min, 20 cycles of denaturation at 98 °C for 60 s, annealing at 62 °C for
60 s, extension at 72 °C for 90 s, and a final extension at 72 °C for 10 min. For each cell culture sample, at least 150 µg was used for PCR1 (split into
individual reactions and pooled after PCR1), and for each tumour sample,
at least 200 µg (or all gDNA available) was used. PCR2 was used to add the
Illumina adapters and barcode the samples, with 10 µl-equivalent of PCR1
mix and 0.2 µM of barcoded primers (PCR2 F Barcode 1–6 and R Barcode
1–6 from ref. [28]) and 6 individual reactions performed for each sample. Cycling parameters were an initial denaturation at 98 °C for 5 min, 10 cycles
of denaturation at 98 °C for 45 s, annealing at 62 °C for 35 s, extension at
72 °C for 90 s, and a final extension at 72 °C for 5 min. PCR3 was used to
further amplify the product, given low yields and amplification artefacts
due to long primers in PCR2. PCR3 was performed with 0.2 µM of primers
PCR3F
(AATGATACGGCGACCACCGAGATC)
and
PCR3R
(CAAGCAGAA-
GACGGCATACGAG) and 4 ng of purified PCR2 product. One reaction from
pooled PCR2 product was performed. Cycling parameters were an initial
denaturation at 98 °C for 2 min, 10 cycles of denaturation at 98 °C for 30 s,
annealing at 61 °C for 35 s, extension at 72 °C for 45 s, and a final extension
at
72 °C
for
10 min. Cell culture Fifty million cells were harvested from trypsinised cell suspensions, rinsed
with PBS and stored at −80 °C. Genomic DNA (gDNA) was isolated using
the QIAamp DNA Blood Maxi Kit (QIAGEN, Hilden, Germany). For tumour
samples, harvested tumour tissue was cut into small fragments using a
scalpel blade and flash-frozen in liquid nitrogen at 0.5 g/tube. Genomic
DNA was isolated as described [28] with volumes scaled 1.5× for cells and
3.5× for up to 0.5 g tumour. For tumours >0.5 g, tissue was divided into
multiple tubes, and gDNA was isolated from each tube and then pooled. Genomic DNA was desalted by adding NaCl to 0.2 M, followed by cold
ethanol to precipitate the DNA and centrifugation at 18,000 × g to pellet
the DNA. The pellet was rinsed once with cold, freshly prepared 70%
ethanol, allowed to air-dry for 10 min and then dissolved in 10 mM Tris, pH
8.0, by heating to 50 °C for 1 h. The gDNA was quality assessed by
Nanodrop and agarose gel electrophoresis (0.8%/TBE) and quantified by
Qubit DNA-BR assay (ThermoFisher Scientific). The UT-SCC cell lines were derived from head and neck squamous cell
carcinoma tumours by Dr Reidar Grénman (University of Turku, Turku, Finland)
and supplied by Prof. Bradly Wouters (University Health Network, Toronto,
Canada). HCT116/54C is an HCT116 subline that originated from a mixed
culture with UT-SCC-54C cells [34]. All cell lines were passaged in minimum
essential media (ThermoFisher Scientific, Waltham, MA) with 10% foetal calf
serum (Moregate Biotech, Hamilton, New Zealand), 4.5 mg/mL D-glucose
(Sigma-Aldrich, St Louis, MO) and 20 mM HEPES (Sigma-Aldrich) for up to
12 weeks, from authenticated frozen stocks [34] at 37 °C in humidified 5% CO2
incubators. All cell lines were confirmed to be Mycoplasma negative by
PlasmoTest (InvivoGen, San Diego, CA). Penicillin/streptomycin (ThermoFisher
Scientific) was added during the expansion of cultures for inoculation
into mice. Polymerase chain reaction Primers
were
ordered
from
Integrated
DNA
Technologies (Coralville, IA), with HPLC-purified DNA oligos used for
PCR1 and PCR3 and desalted Ultramer oligos used for PCR2. Positive
controls for PCR used lentiguide-Puro EGFP gRNA (Addgene #80036),
which contained a gRNA sequence not present in the GeCKOv2 library. Transductions To produce Cas9-expressing HCT116/54C and UT-SCC-74B cells, 5 × 104
cells in normal culture medium with 8 µg/ml polybrene were transduced
with lentiCas9-Blast lentivirus at a multiplicity of infection of 0.2–0.4. Blasticidin (10 µg/ml) was applied 24 h after transduction to select stable
transductants. Cas9-expressing cells were expanded and transduced with
the GeCKOv2 lentiviral library, with puromycin selection (1–1.5 µg/ml)
2–4 days after transduction. For HCT116/54C, 6.4 × 107 cells were
transduced with a multiplicity of infection of 0.22 to obtain 1.25 × 107
individual transductants (HCT116/54C GeCKO library; 89% with a single
gRNA assuming Poisson statistics), and for UT-SCC-74B, 6 × 107 cells were
transduced with a multiplicity of infection of 0.18 to obtain 9.8 × 106
individual transductants (UT-SCC-74B GeCKO library; 91% receiving a single
gRNA). Cell populations were expanded for up to 8 weeks and either
cryopreserved at scale (2–3 × 107 cells/tube) or used immediately for
inoculations. Lentiviral packaging lentiCas9-Blast (AddGene, Watertown, MA; #52962) was packaged in
HEK293T cells using the pMD2.G (Addgene #12259) and psPAX2 (Addgene
#12260) packaging plasmids transfected with Lipofectamine 2000 (Ther-
moFisher Scientific). The Human GeCKOv2 A and B libraries in lentiGuide-
Puro were amplified as described [35], pooled at equimolar concentrations
and packaged in the same way. Filtered unconcentrated lentiCas9-Blast
lentivirus was used for transductions, while GeCKOv2 library lentivirus was
concentrated by centrifugation at 10,000 × g for 5 h with a 20% sucrose
cushion. INTRODUCTION Animals were randomised within blocks to receive treatment
with 6-thioguanine (3 mg/kg in PBS qd × 5; Sigma-Aldrich), evofosfamide
(50 mg/kg in saline qd × 5/week for 3 weeks; Threshold Pharmaceuticals,
San Francisco, CA) or saline (qd × 5/week for 3 weeks) once median
tumour volume reached 250 mm3. Treatments were administered by
intraperitoneal injection at 10 ml/kg. All animals had ad libitum access to
food and water in microisolator cages and were maintained on a 12 h
light/dark cycle. Animal health and welfare were monitored regularly with
animals culled by cervical dislocation or CO2 asphyxiation if their condition
deteriorated, if they lost in excess of 20% of their pre-manipulation
bodyweight or if ethical tumour size limits were reached (longest tumour
diameter ≥20 mm). Tumour volume was measured by electronic callipers
using the formula π/6 × width × length2 and was blinded to animal
treatment. Differences in tumour growth were assessed by log-rank test
on the time taken for tumours to quadruple in size. required for a 50% probability of tumour development, were determined
using logistic regression fitted to the proportion of tumours that
developed [36], with a tumour considered to have formed if it reached
250 mm3 in volume within 100 days from inoculation. For the pilot study, a
small sample size of n = 3 per group was chosen. For the larger study, a
sample size of n = 36 tumours in total was chosen based on available
resources. Animals were randomised within blocks to receive treatment
with 6-thioguanine (3 mg/kg in PBS qd × 5; Sigma-Aldrich), evofosfamide
(50 mg/kg in saline qd × 5/week for 3 weeks; Threshold Pharmaceuticals,
San Francisco, CA) or saline (qd × 5/week for 3 weeks) once median
tumour volume reached 250 mm3. Treatments were administered by
intraperitoneal injection at 10 ml/kg. All animals had ad libitum access to
food and water in microisolator cages and were maintained on a 12 h
light/dark cycle. Animal health and welfare were monitored regularly with
animals culled by cervical dislocation or CO2 asphyxiation if their condition
deteriorated, if they lost in excess of 20% of their pre-manipulation
bodyweight or if ethical tumour size limits were reached (longest tumour
diameter ≥20 mm). Tumour volume was measured by electronic callipers
using the formula π/6 × width × length2 and was blinded to animal
treatment. INTRODUCTION Differences in tumour growth were assessed by log-rank test
on the time taken for tumours to quadruple in size. INTRODUCTION Since that time, a large number of in vitro whole genome screens
have been undertaken utilising multiple different guide RNA
(gRNA) libraries to identify essential genes [10–12] and uncover
novel genes implicated in tumour growth [13, 14], drug sensitivity
and resistance [15–18], synthetic lethal interactions [12, 19–21]
and immunotherapy response [22, 23]. However, while CRISPR/
Cas9 screens provide a powerful approach for gene discovery
in vitro, the complex multicellular interactions within the tumour
microenvironment [24, 25] means that the genes controlling cell In this study, we investigate the importance of several
experimental parameters for in vivo CRISPR screens and their Received: 31 May 2023 Revised: 8 August 2023 Accepted: 29 August 2023
Published online: 8 September 2023 T.W. Lee et al. 1611 impacts on clonal diversity as measured by the distribution of
gRNA counts in the tumour samples. We first evaluate the tumour-
initiating ability of 22 head and neck squamous cell carcinoma
lines in comparison with an HCT116 subline (HCT116/54C). We
construct CRISPR/Cas9 libraries of two selected cell lines with
different numbers of tumour-initiating cells and compare between
the cell lines and between mouse hosts when these libraries are
grown as tumour xenografts. Using the most promising combina-
tion of cell line and mouse host from our initial experiments, we
then conducted a larger experiment with four experimental
groups. We report that the major limiting factor in detecting
gRNA-driven selection is the high variance in gRNA counts
between tumours, which increases with time as the tumours
grow. We use our data to simulate a reduction in library sizes and
explore how this alters count variance and statistical power. Our
data and analyses demonstrate the key parameters that must be
optimised to ensure successful in vivo CRISPR screens and suggest
a pathway for the rational design of sufficiently powered screens. required for a 50% probability of tumour development, were determined
using logistic regression fitted to the proportion of tumours that
developed [36], with a tumour considered to have formed if it reached
250 mm3 in volume within 100 days from inoculation. For the pilot study, a
small sample size of n = 3 per group was chosen. For the larger study, a
sample size of n = 36 tumours in total was chosen based on available
resources. Simulations of reduced library sizes y
To generate datasets containing fewer gRNAs, we randomly combined
gRNAs into bins of 2, 5, 10, 20, 50, 100, 200, 400, 800 and 1600 gRNAs, with
binning performed separately for targeting and non-targeting gRNAs; the
counts of any excess gRNAs that could not fill a full bin were discarded. The
binned gRNAs were further subsampled to 100 000 (no binning), 50 000
(bin size = 2), 20 000, 10 000, 4000, 2000, 1000, 500, 250, 125 and 62 (bin
size = 1600) gRNAs to reduce the dependence on particular gRNAs. A total
of 100 simulated datasets were generated for each number of gRNAs. We
conducted analyses on either combined small tumours (total n = 11
combining pilot HCT116/54C tumours and 14 d tumours in treatment
experiment)
or
large
tumours
(total
n = 28
combining
no
drug,
6-thioguanine and evofosfamide groups), with a varying number of
tumour samples randomly drawn from each dataset to assess accuracy and
precision of estimating dispersion from datasets of different sizes. Data
sets were normalised by MPM (a = 0, m = 0, pseudocount = 0.02) based
on subsampled NTC gRNAs (bin sizes ≤50) or all subsampled gRNAs (bin
sizes > 50). The common dispersion was calculated using edgeR in ‘classic’
mode with all samples in a single group. Power analyses were conducted
on the RnaSeqSampleSize package [39] using the estPower function with
dispersion
(phi)
set
to
the
common
dispersion
estimate. For
all
comparisons, mean count (lambda) was set to 10, and default options of
1 for normalisation factor and sample size ratio, FDR of 0.05, and 1%
prognostic genes. Power was calculated for various combinations of
sample size and effect size. Processing of sequencing data g
q
g
A
snakemake-based
pipeline
for
processing
sequencing
data
was
developed
(https://gitlab.com/twlee79/pooled_screen_counts). Sequen-
cing data were demultiplexed according to the reverse index by the
Illumina platform and converted to FASTQ format. These data were then
demultiplexed according to the forward index using cutadapt v1.18 with
non-internal adapter sequences, allowing up to 1 nucleotide mismatch. Fastqc 0.11.7 was carried out on the demultiplexed reads to check for
sequencing quality. Next, cutadapt was used to trim poor quality bases and
trim the vector 5′ and 3′ backbone sequence flanking the gRNA sequences. The quality threshold of 10 was used, and the 5′/3′ adapters were specified
as linked adapters, allowing an adapter error rate of 0.1 and 19–21
nucleotide resulting sequences (expected 20-nucleotide gRNA sequences);
99.98% of demultiplexed reads were retained after trimming. The gRNA
sequences were then aligned to the gRNA sequences present in the
GeCKOv2 library using bowtie 2. Replicated gRNA sequences in the
GeCKOv2 library were collapsed to individual entries prior to alignment
(119,461 unique gRNAs; any replicated gRNA sequences were labelled
“non-unique”). Alignment scoring in bowtie 2 was set to local alignment
mode with a score of 10 for a match, 4-6 for a mismatch (depending on
quality), and per nucleotide gap penalty of −1, reporting the best
alignment and also the best alternative alignment score. The number of
reads aligned to each gRNA in the library was counted using a custom
script (count_fgs_sam; https://gitlab.com/twlee79/count_fgs_sam). The
minimum alignment score for a read to be counted was set to 189—
allowing for up to two mismatches or a 1-nt gap—with the additional
criterion that only unambiguous alignments were counted. An unambig-
uous alignment was defined as a read where the main alignment had a
score of 3 or greater than the best alternative alignment, i.e. the main
alignment had fewer mismatches or gaps than the best alternative. A
mean of 95.2% of trimmed reads aligned unambiguously and contributed
to the counts. RESULTS
S l
i Selection of suitable cell lines for in vivo CRISPR/Cas9 screens
We hypothesised that a cell line with a high proportion of tumour-
initiating cells would be better suited for in vivo CRISPR/
Cas9 screens as it would undergo a reduced population bottle-
neck due to a larger founder population and therefore be less
sensitive to stochastic effects. We evaluated 22 UT-SCC head and
neck squamous cell carcinoma cell lines and an HCT116 colon
carcinoma subline (HCT116/54C) by inoculating immunodeficient
mice subcutaneously with different numbers of cells to identify
which cell lines could initiate tumours with few cells. In initial
experiments, only 11 of 23 cell lines grew as tumour xenografts
within 100 days of inoculation of 5 × 106 cells into NIH-III mice
(Fig. 1A). Four of these cell lines (UT-SCC-1B, UT-SCC-54B, UT-SCC-
74A, and UT-SCC-76A) had low tumour take rates and slow growth
with ≤50% of tumours established by day 90, while two others
(UT-SCC-1A and UT-SCC-42B) had frequent ulceration of skin over
the tumours. Read count normalisation We calculated log normalised counts per million (log-ncpm) using a new
normalisation method called MPM—mean of pairwise log expression ratios
(M)—that we developed to deal with data containing many zero counts on
the low end and inflated counts on the high end (Supplemental Methods). As the GeCKOv2 gRNA library contains 1000 non-targeting controls (NTCs),
which can be assumed to be neutral, and thus non-differential on average,
we calculated the size factors from NTC gRNAs alone with no a or m
trimming (a = 0, m = 0), and a pseudocount of 0.02. The normalised counts
thus represent counts relative to neutral gRNAs. Unless stated otherwise,
pseudocounts are used for normalisation only, and we present log2
normalised counts per million as-is without a pseudocount (zeroes at
negative infinity; plotted at y-axis minimum). Animal experiments Six- to eight-week-old female NOD scid gamma (NSG; NOD.Cg-Prkdcscid
Il2rγtm1Wjl/SzJ; Jackson Laboratory) or NIH-III mice were bred in the Vernon
Jansen Unit, University of Auckland, Auckland, New Zealand. Mice were
inoculated with unmodified cell lines at a range of cell numbers, or
HCT116/54C or UT-SCC-74B GeCKO libraries (107 cells per site), subcuta-
neously into bilateral flanks. TD50 values, defined as the number of cells Cancer Gene Therapy (2023) 30:1610 – 1623 T.W. Lee et al. 1612 cells with the gRNA survive), and the probability of the gRNA being
detected is given by 1 1 p
ð
Þni (i.e. the probability that at least one cell
with the gRNA survives to form a clone). A likelihood function was defined
based on the joint probability for the observed detection of a given subset
of gRNAs (non-targeting or all gRNAs), and p and its variance was
estimated using maximum likelihood estimation, with ni parameterised by
the proportion of counts for gRNA i in the inoculum multiplied by the
number of cells inoculated. The median number of surviving clones per
gRNA was then estimated as the median of pni across all gRNAs. To
account for the variable number of counts in each sample, the same
detection threshold (1 count) was used across all samples, but we
subsampled to a target NTC count of 105 counts (approximately 7 million
total counts) prior to estimating p. To reduce the dependence of the
estimate on particular subsamples, a total of 99 subsamples per sample
was performed, and the median was used. Three large tumour samples
had fewer than 105 NTC counts and were excluded. Agarose gel electrophoresis (1.5%/Tris-Borate-EDTA) was used to confirm
PCR products (317 for PCR1, ~360 for PCR2/PCR3). Samples were
sequenced on a NextSeq500 (Illumina, San Diego, CA) using high-output,
2 × 150 bp flow cells (Illumina). Analysis of gRNA counts with edgeR y
g
g
The edgeR function estimateDisp was used to estimate the dispersion of
gRNA counts with MPM-normalised library sizes. The gRNA data was
filtered to retain only gRNAs detected in at least 6 large tumour samples
and with at least 12 reads in total from the large tumour samples. The
dispersion was estimated in edgeR ‘classic’ mode (using the quantile-
adjusted conditional maximum likelihood method) for a single-factor
experiment (with a level of the factor for each experimental condition) [37]. Hypothesis testing between experimental groups at the gRNA level was
performed using the edgeR exactTest function. Gene-level analysis was
conducted using the α-RRA method [38] with gRNAs ranked by edgeR p-
value and α set to a false discovery rate (FDR) cutoff of 0.2. RRA was
conducted separately for positive (i.e. positive log fold change (FC) vs. control) and negative selection (negative logFC vs. control). The five cell lines with suitable growth kinetics (UT-SCC-16A,
-74B, -110B, -126A and HCT116/54C) were selected to conduct
limiting dilution assays in NIH-III and NSG mice to estimate the
TD50. We initially screened all cell lines for growth as tumour
xenograft models in NIH-III mice by inoculating 5 × 106 cells per
flank into 3–5 mice, followed by 106 and 105 cells for those with a
high take rate (>75%). For tumour models that grew as xenografts
at 105 or 106 cells, we proceeded to test in NSG mice, which were
expected to be more conducive to tumour growth, at 105, 104 and Estimation of the number of clones in tumour samples three of four NSG mice inoculated bilaterally with 104
UT-SCC-126A required culling early due to ~20% bodyweight loss). with slightly lower representation in NIH-III hosts at 88.3–93.5%
(Fig. 2B). The vast majority of gRNAs were also detected in UT-SCC-
74B GeCKO cells (98.5%) but UT-SCC-74B GeCKO tumours in NSG
mice had considerably lower representation of 66.0–68.5%, with
many detected with only a single read (Fig. 2B; Table S1). In
considering only NTC gRNAs, >98% were detected in all HCT116/
54C GeCKO tumours but only ~86% in UT-SCC-74B GeCKO
tumours (Fig. 2B; Table S2). This suggests that cells receiving
non-targeting gRNAs had a growth or survival advantage within
the tumours compared to cells receiving most gRNAs targeting
a gene. The decreases in representation in the tumour samples were
accompanied by disproportionate increases in the read counts of
the top-ranked gRNAs (i.e. those with the highest counts;
Table S1). The unequal read count distributions in the tumour
samples were also evident in the Lorenz curves of the gRNA count
data (Fig. 2C), with the UT-SCC-74B GeCKO/NSG tumours showing
extremely unequal read counts (top 1% of gRNAs accounting for
76–78% of reads). The NTC gRNAs showed only slightly smaller
read count inequality than gene-targeting gRNAs, suggesting that
the major driver is stochastic effects rather than changes in fitness
(Table S2, Fig. S1A). As a metric of inequality, we calculated the
Hoover index, which can be interpreted as the proportion of reads
needed to be redistributed to form a uniform distribution (Fig. 2D;
Tables S1 and S2). The Hoover indices followed the inverse pattern
of gRNA representation (compare Fig. 2D to B). The inverse
relationship suggests that the apparent loss of gRNA representa-
tion is at least partly driven by difficulty sampling low-frequency
gRNAs in highly unequal gRNA distributions. Estimation of the number of clones in tumour samples All cells were assumed to have an independent and equal probability p of
surviving to form a clone. If ni is the number of cells containing gRNA i that
are inoculated, the detection of that gRNA was modelled as the outcome
of a set ni Bernoulli trials. Under these assumptions, the probability of the
gRNA being not detected is given by 1 p
ð
Þni (i.e. the probability that no Cancer Gene Therapy (2023) 30:1610 – 1623 T.W. Lee et al. 1613 Fig. 1
Establishment of tumour xenograft models. A Rate of tumour establishment for UT-SCC and HCT116/54C cell lines inoculated
bilaterally in NIH-III mice at 5 × 106 cells per flank. B Frequency of tumour establishment for UT-SCC and HCT116/54C cell lines inoculated at
different cell inocula into NIH-III (≥106) or NSG (≤105) mice. C Comparison of HCT116/54C tumour growth in NIH-III and NSG mice at different
cell inocula. D The rate of tumour establishment for HCT116/54C at different cell inocula. E Comparison of tumour establishment rate and
growth for HCT116/54C tumours in NSG (left panel) and NIH-III (right panel) mice inoculated with 105 cells. 161 Fig. 1
Establishment of tumour xenograft models. A Rate of tumour establishment for UT-SCC and HCT116/54C cell lines inoculated
bilaterally in NIH-III mice at 5 × 106 cells per flank. B Frequency of tumour establishment for UT-SCC and HCT116/54C cell lines inoculated at
different cell inocula into NIH-III (≥106) or NSG (≤105) mice. C Comparison of HCT116/54C tumour growth in NIH-III and NSG mice at different
cell inocula. D The rate of tumour establishment for HCT116/54C at different cell inocula. E Comparison of tumour establishment rate and
growth for HCT116/54C tumours in NSG (left panel) and NIH-III (right panel) mice inoculated with 105 cells. 103 cells until fewer than 50% of tumours formed. Tumours were
formed in 100% of NIH-III mice at ≥106 for all cell lines, but the
establishment rate fell with cell inocula ≤104 in NSG mice (Fig. 1B). As expected, tumour growth took longer on average with smaller
inocula (Fig. 1C, D) and tumour establishment rate was higher and
faster in NSG mice than NIH-III mice (Fig. 1E). The lowest TD50 of
approximately 1100 cells was estimated for HCT116/54C and UT-
SCC-126A, followed by UT-SCC-16A, UT-SCC-110B and UT-SCC-74B
(Table 1). Despite its low TD50, UT-SCC-126A was not investigated
further because it caused considerable weight loss in some
animals (e.g. Pilot xenograft experiments with HCT116/54C and UT-SCC-
74B GeCKOv2 libraries 74B GeCKOv2 libraries
We next compared tumour xenografts of GeCKOv2 libraries of
HCT116/54C (joint lowest TD50) and UT-SCC-74B (a second model
with a higher TD50) cell lines to ascertain whether the TD50 was
consistent with model suitability for in vivo screens. Two mouse
strains—NSG and NIH-III mice—were compared by inoculating 107
cells and harvesting tumours when the smallest in each group
reached ~250 mm3. HCT116/54C GeCKO tumours grew faster in
NSG mice than NIH-III mice and faster than UT-SCC-74B GeCKO
tumours, which grew equally in both mouse strains (Fig. 2A). Almost all gRNAs were detected in the GeCKOv2 plasmid library
(99.98%), the HCT116/54C GeCKO library used for inoculation
(99.7%), and cells cultured in vitro for a further 12 d (99.3%; Fig. 2B;
Table S1). We observed high representation in HCT116/54C
GeCKO tumours in NSG hosts with 92.2–96.9% gRNAs detected, We next compared tumour xenografts of GeCKOv2 libraries of
HCT116/54C (joint lowest TD50) and UT-SCC-74B (a second model
with a higher TD50) cell lines to ascertain whether the TD50 was
consistent with model suitability for in vivo screens. Two mouse
strains—NSG and NIH-III mice—were compared by inoculating 107
cells and harvesting tumours when the smallest in each group
reached ~250 mm3. HCT116/54C GeCKO tumours grew faster in
NSG mice than NIH-III mice and faster than UT-SCC-74B GeCKO
tumours, which grew equally in both mouse strains (Fig. 2A). y
Almost all gRNAs were detected in the GeCKOv2 plasmid library
(99.98%), the HCT116/54C GeCKO library used for inoculation
(99.7%), and cells cultured in vitro for a further 12 d (99.3%; Fig. 2B;
Table S1). We observed high representation in HCT116/54C
GeCKO tumours in NSG hosts with 92.2–96.9% gRNAs detected, Cancer Gene Therapy (2023) 30:1610 – 1623 T.W. Lee et al. 1614 Table 1. Cell line characteristics and TD50. Pilot xenograft experiments with HCT116/54C and UT-SCC-
74B GeCKOv2 libraries HCT116/54C GeCKO tumours (n = 36) in female NSG mice
were allowed to grow until the median tumour size reached
~250 mm3 then the mice were randomised into four groups: one
(A) in which tumours were harvested immediately, a mock
treatment group (B) and two drug treatment groups (C with 6-
thioguanine, 6-TG and D with evofosfamide). Tumours in B-D were
allowed to grow until the largest tumour in each group reached
ethical size limits, at which point all tumours in the group were
collected (day 38, 42 and 43 post inoculation for groups B, C and
D, respectively). There was a small non-significant decrease in
tumour growth for the two drug treatment groups compared to
controls (Fig. 3A). Representation of gRNAs in the group A
tumours was high (90.1 ± 3.5%; mean ± SD) but was lower than in
the similarly-sized tumours in the pilot study (94.8 ± 2.8%), most
likely reflecting that the tumours grew slightly slower than in the
pilot study, taking 14 days to reach an average size of 230 mm3
compared to 11 days to reach an average of 340 mm3. Moreover,
there was a substantial decrease in representation of all gRNA and
NTC gRNAs in tumours in groups B–D relative to the group A
tumours at day 14 (Fig. 3B; Table S3). A much smaller loss of
representation was observed relative to the cell inoculum by
keeping the cells used for inoculation in culture for the duration of
the in vivo screen (95.0% gRNAs detected after 38 additional
days). p
g
pp
Following MPM normalisation, each sample had similar median
normalised gRNA counts (Fig. 2E; Fig. S1B; Fig. S9; Tables S1 and S2). This data representation again reveals that the loss of representation
from the plasmid to the cell libraries and the tumours is
accompanied by wider, more skewed gRNA distribution, with the
upper tails becoming progressively more extreme. Similar to the small tumours in the pilot study, the decreases in
gRNA representation were mirrored by increases in inequality and
skew in the gRNA counts. Lorenz curves and Hoover indices show
inequality was much greater in the 14-day tumours (Hoover indexes
0.54–0.62) compared to the cell inoculum (0.29) or cells cultured for
an additional 14 days after inoculation (0.32) and somewhat greater
than that of cells cultured for an additional 38 days after inoculation
(0.50; Fig. 3C, D; Table S3). Pilot xenograft experiments with HCT116/54C and UT-SCC-
74B GeCKOv2 libraries All large (38–43 day) tumours had Pilot xenograft experiments with HCT116/54C and UT-SCC-
74B GeCKOv2 libraries Cell line
Primary site
Type
TD50*
HCT116/54C
Colon
Primary
1100
UT-SCC-126A
Labii inferioris
Primary
1100; mice lose weight
UT-SCC-16A
Lingus
Primary
5400
UT-SCC-110B
Gingiva, maxillary sinus
Metastasis
7700
UT-SCC-74B
Lingus
Recurrent
9200
UT-SCC-1A
Gingiva
Primary
<106; ulcerates
UT-SCC-42B
Supraglottic larynx
Metastasis
<106; ulcerates
UT-SCC-1B
Gingiva
Recurrent
Low take rate
UT-SCC-54B
Buccal mucosa
Recurrent
Low take rate
UT-SCC-74A
Lingus
Primary
Low take rate
UT-SCC-76A
Lingus
Primary
Low take rate
UT-SCC-16B
Lingus
Metastasis
Did not grow
UT-SCC-19A
Glottic larynx
Primary
Did not grow
UT-SCC-19B
Glottic larynx
Recurrent
Did not grow
UT-SCC-24A
Lingus
Primary
Did not grow
UT-SCC-42A
Supraglottic larynx
Primary
Did not grow
UT-SCC-46A
Gingiva, maxilla
Primary
Did not grow
UT-SCC-54A
Buccal mucosa
Primary
Did not grow
UT-SCC-59C
Parotid
Metastasis
Did not grow
UT-SCC-60A
Tonsilla
Primary
Did not grow
UT-SCC-63A
Gingiva, mandibula
Primary
Did not grow
UT-SCC-76B
Lingus
Recurrent
Did not grow
UT-SCC-110A
Gingiva, maxillary sinus
Recurrent
Did not grow
aLow take rate indicates ≤50% of tumours established by day 90 at 5 × 106 cells in NIH-III mice. Did not grow indicates no tumours were established by day 90
at 5 × 106 cells in NIH-III mice. Table 1. Cell line characteristics and TD50. aLow take rate indicates ≤50% of tumours established by day 90 at 5 × 106 cells in NIH-III mice. Did not grow indicates no tumours were established by day 90
at 5 × 106 cells in NIH III mice aLow take rate indicates ≤50% of tumours established by day 90 at 5 × 106 cells in NIH-III mice. Did not grow indicates no tumours were established by day 90
at 5 × 106 cells in NIH-III mice. model. HCT116/54C GeCKO tumours (n = 36) in female NSG mice
were allowed to grow until the median tumour size reached
~250 mm3 then the mice were randomised into four groups: one
(A) in which tumours were harvested immediately, a mock
treatment group (B) and two drug treatment groups (C with 6-
thioguanine, 6-TG and D with evofosfamide). Tumours in B-D were
allowed to grow until the largest tumour in each group reached
ethical size limits, at which point all tumours in the group were
collected (day 38, 42 and 43 post inoculation for groups B, C and
D, respectively). There was a small non-significant decrease in
tumour growth for the two drug treatment groups compared to
controls (Fig. 3A). Pilot xenograft experiments with HCT116/54C and UT-SCC-
74B GeCKOv2 libraries Representation of gRNAs in the group A
tumours was high (90.1 ± 3.5%; mean ± SD) but was lower than in
the similarly-sized tumours in the pilot study (94.8 ± 2.8%), most
likely reflecting that the tumours grew slightly slower than in the
pilot study, taking 14 days to reach an average size of 230 mm3
compared to 11 days to reach an average of 340 mm3. Moreover,
there was a substantial decrease in representation of all gRNA and
NTC gRNAs in tumours in groups B–D relative to the group A
tumours at day 14 (Fig. 3B; Table S3). A much smaller loss of
representation was observed relative to the cell inoculum by
keeping the cells used for inoculation in culture for the duration of
the in vivo screen (95.0% gRNAs detected after 38 additional
days). The skewed distribution of read counts, especially in UT-SCC-
74B tumours, meant that the data were zero-inflated at one end
and contained very high counts for a few gRNAs at the other end. We found that most count normalisation methods, including the
commonly used TMM [40] and RLE [41] methods, as well as the
GMPR method [42] developed for zero-inflated microbiome data,
performed poorly with these highly unequal count distributions
containing many sampling zeroes. Therefore, we devised a new
normalisation procedure, which we call MPM, for our data to
account for its unique characteristics (Supplemental Methods and
Results; Figs. S4–S7). MPM is a generalisation of the GMPR method,
but a key difference is the treatment of zeroes—these are
excluded completely in GMPR but are substituted in MPM for
pseudocounts when a zero is present in one sample during a
pairwise comparison (double zeroes are excluded). This treatment
is more consistent with all zero counts being modelled as
sampling zeroes, as suggested in previous work [43]. The exclusion
of all zeroes in GMPR results in the loss of information that a count
is lower in one sample than another sample and can bias library
size estimates upwards; MPM using an appropriate pseudocount
value performs better in this regard (see Supplemental Results). model. Increased read count inequality following subsequent growth
of HCT116/54C GeCKO tumours Using the best combination of cell line and mouse host, we
evaluated the feasibility of conducting an in vivo screen with this Cancer Gene Therapy (2023) 30:1610 – 1623 T.W. Lee et al. 1615 Pilot whole genome in vivo screens for HCT116/54C and UT-SCC-74B GeCKOv2 libraries. A Growth curves for HCT116/54C and UT-
4B tumours in NSG and NIH-III mice. Bars represent the mean and SEM of 3–6 tumours. B Percentage of all or NTC gRNAs detected for
id, HCT116/54C GeCKO cell inoculum, HCT116/54C GeCKO tumours in NSG mice, HCT116/54C GeCKO tumours in NIH-III mice and UT-
4B GeCKO cell inoculum and tumours in NSG mice. Replicates for plasmid and cell samples are PCR replicates from the same gDNA
e (n = 2 each); tumour replicates are individual tumours in separate hosts (n = 3 per group). The bar indicates mean ± SEM. C Lorenz
s to show the distribution of all gRNA read counts. The curve for summed PCR replicates (plasmid and cell samples) or median tumours
oover index) in a group is highlighted. The black line is the line of equality (plas: plasmid; HCT: HCT116/54C; 74: UT-SCC-74B; NIH: NIH-III). over index of each sample as a measure of inequality of the read counts for all and NTC gRNAs. E Letter-value plot of log normalised
s per million (log-ncpm) for all gRNAs in plasmid, cell inocula and GeCKO tumour samples (zeroes given pseudocount of 0.5). The white
nside the black boxes indicates the median (M), and the black boxes indicate the upper/lower quartiles (F; fourths). The next smallest
indicate the upper/lower eighths (E) and so on. Counts for plasmid and cell samples were summed from two PCR replicates prior to
alisation. The remaining outliers are shown as open circles. 161 Fig. 2
Pilot whole genome in vivo screens for HCT116/54C and UT-SCC-74B GeCKOv2 libraries. A Growth curves for HCT116/54C and UT-
SCC-74B tumours in NSG and NIH-III mice. Bars represent the mean and SEM of 3–6 tumours. B Percentage of all or NTC gRNAs detected for
plasmid, HCT116/54C GeCKO cell inoculum, HCT116/54C GeCKO tumours in NSG mice, HCT116/54C GeCKO tumours in NIH-III mice and UT-
SCC-74B GeCKO cell inoculum and tumours in NSG mice. Replicates for plasmid and cell samples are PCR replicates from the same gDNA
sample (n = 2 each); tumour replicates are individual tumours in separate hosts (n = 3 per group). Increased read count inequality following subsequent growth
of HCT116/54C GeCKO tumours The bar indicates mean ± SEM. C Lorenz
curves to show the distribution of all gRNA read counts. The curve for summed PCR replicates (plasmid and cell samples) or median tumours
(by Hoover index) in a group is highlighted. The black line is the line of equality (plas: plasmid; HCT: HCT116/54C; 74: UT-SCC-74B; NIH: NIH-III). D Hoover index of each sample as a measure of inequality of the read counts for all and NTC gRNAs. E Letter-value plot of log normalised
counts per million (log-ncpm) for all gRNAs in plasmid, cell inocula and GeCKO tumour samples (zeroes given pseudocount of 0.5). The white
line inside the black boxes indicates the median (M), and the black boxes indicate the upper/lower quartiles (F; fourths). The next smallest
boxes indicate the upper/lower eighths (E) and so on. Counts for plasmid and cell samples were summed from two PCR replicates prior to
normalisation. The remaining outliers are shown as open circles. extremely unequal gRNA distributions as shown by the Lorenz
curves, Hoover indices of 0.89–0.96, and 74–96% of reads from only
the top 1% of gRNAs. Letter-value plots of normalised gRNA counts
similarly showed distribution becoming progressively wider going
from the cell culture samples to the 14-day tumours and then large
(38–43 day) tumours (Fig. 3E; Fig. S10). The latter gRNA distributions
all had very long upper tails indicating a strong skew towards relatively few gRNAs having very high counts, while most others had
zero or very few counts. In the most skewed large tumour sample
(C4R), 17.6% of reads were from a single gRNA (Table S3). The
median gRNA count was zero for all large tumours. As with the pilot
study, similar but slightly smaller increases in count inequality and
skew could be seen in an analysis of NTC gRNAs in the tumour
samples (Fig. 3B, D; Fig. S1C, D; Table S4). Cancer Gene Therapy (2023) 30:1610 – 1623 T.W. Lee et al. Random variation in clonal dynamics precludes gRNA-induced
selection in HCT116/54C GeCKO tumours
The representation and count distribution data in HCT116/54C
GeCKO tumours suggested a greater loss of targeting gRNAs
compared to non-targeting controls. To more directly test this,
we compared the ratio of the 90th percentile read counts o
gRNAs to the 90th percentile read counts of the NTC gRNAs. Increased read count inequality following subsequent growth
of HCT116/54C GeCKO tumours 90th percentile was used to obtain a reasonable numbe
counts since the median and upper quartile were zero
several large tumour samples. If the distribution of read co
T.W. Lee et al. 1616 Random variation in clonal dynamics precludes gRNA-induced
selection in HCT116/54C GeCKO tumours
h
d
d
b
d we compared the ratio of the 90th percentile read counts of all
gRNAs to the 90th percentile read counts of the NTC gRNAs. The
90th percentile was used to obtain a reasonable number of
counts since the median and upper quartile were zero for
several large tumour samples. If the distribution of read counts we compared the ratio of the 90th percentile read counts of all
gRNAs to the 90th percentile read counts of the NTC gRNAs. The
90th percentile was used to obtain a reasonable number of
counts since the median and upper quartile were zero for
several large tumour samples. If the distribution of read counts Random variation in clonal dynamics precludes gRNA-induced
selection in HCT116/54C GeCKO tumours
The representation and count distribution data in HCT116/54C
GeCKO tumours suggested a greater loss of targeting gRNAs
compared to non-targeting controls. To more directly test this, The representation and count distribution data in HCT116/54C
GeCKO tumours suggested a greater loss of targeting gRNAs
compared to non-targeting controls. To more directly test this, Cancer Gene Therapy (2023) 30:1610 – 1623 For C, D, the numbers above each individual targeting gRNA represent previously reported
estimates of guide activity [14], with scores approaching 1 representing highly effective gRNAs and those approaching 0 representing poorly
performing gRNAs. for all gRNAs and NTC gRNAs was changing uniformly during
tumour growth, this ratio was expected to stay constant for all
groups. Instead, there was a progressive decrease in this ratio
from the cell samples to the small tumours (14 d) to the large
(38–43 d) tumours (Fig. 4A). These data indicate a greater
depletion of cells harbouring targeting gRNAs compared to NTC
gRNAs in the tumours. A likely explanation of this effect is the
overall
negative
selection
of
cells
harbouring
knockouts
compared to control cell lines due to a general loss of fitness
in
these
cells. Thus,
although
there
were
large
random
differences in growth and survival among clones, some effects
of selection could be detected when averaging across a large
number of gRNAs. for all gRNAs and NTC gRNAs was changing uniformly during
tumour growth, this ratio was expected to stay constant for all
groups. Instead, there was a progressive decrease in this ratio
from the cell samples to the small tumours (14 d) to the large
(38–43 d) tumours (Fig. 4A). These data indicate a greater
depletion of cells harbouring targeting gRNAs compared to NTC
gRNAs in the tumours. A likely explanation of this effect is the
overall
negative
selection
of
cells
harbouring
knockouts
compared to control cell lines due to a general loss of fitness
in
these
cells. Thus,
although
there
were
large
random
differences in growth and survival among clones, some effects
of selection could be detected when averaging across a large
number of gRNAs. Given the extremely high variability in the large tumour counts,
we reasoned that detection of any gRNA-driven selection among
the treatment groups would be rare. Unexpectedly, after filtering
for low abundance gRNAs (73,421 targeting gRNAs retained), an
initial analysis of the entire in vivo screen data set (including small
14 d tumours) using the edgeR exact test pipeline [37] resulted in
the detection of a large number of gRNAs significantly selected
either positively or negatively (>10,000 each direction; FDR < 0.1)
for the comparisons between untreated vs. 6-TG and untreated vs. evofosfamide. Further investigation revealed that this was caused
by the inclusion of the small tumours during the analysis. The bar indicates mean ± SEM. B Distribution of log2 normalised cpm of
the top 16 gRNAs (by p-value control versus 6-thioguanine) targeting genes expected to be involved in 6-thioguanine resistance in the
tumour samples. The selected genes were HPRT1, NUDT5 and 23 genes in the KEGG mismatch repair geneset (6-TG = 6-thioguanine,
evo = evofosfamide). Lines are the average log cpm calculated with aveLogCPM (prior count of 0.5), and statistics are for the no drug versus
6-thioguanine comparison using the edgeR exactTest function with dispersion estimated from large tumour samples only. C Variation in
counts of four gRNAs across samples in the large tumour dataset. The four gRNAs represent those with the highest and 10th highest
maximum log normalised cpm across all samples for all or NTC gRNAs. D Variation in counts of the six gRNAs in the library targeting CXCL2
across samples in the large tumour dataset. For C, D, the numbers above each individual targeting gRNA represent previously reported
estimates of guide activity [14], with scores approaching 1 representing highly effective gRNAs and those approaching 0 representing poorly
performing gRNAs. Fig. 4
Assessing gRNA-driven selection in HCT116/54C in vivo screens. A Ratio of counts for the gRNA at the 90th count percentile among
all gRNAs to counts for the NTC gRNA at the 90th count percentile. The bar indicates mean ± SEM. B Distribution of log2 normalised cpm of
the top 16 gRNAs (by p-value control versus 6-thioguanine) targeting genes expected to be involved in 6-thioguanine resistance in the
tumour samples. The selected genes were HPRT1, NUDT5 and 23 genes in the KEGG mismatch repair geneset (6-TG = 6-thioguanine,
evo = evofosfamide). Lines are the average log cpm calculated with aveLogCPM (prior count of 0.5), and statistics are for the no drug versus
6-thioguanine comparison using the edgeR exactTest function with dispersion estimated from large tumour samples only. C Variation in
counts of four gRNAs across samples in the large tumour dataset. The four gRNAs represent those with the highest and 10th highest
maximum log normalised cpm across all samples for all or NTC gRNAs. D Variation in counts of the six gRNAs in the library targeting CXCL2
across samples in the large tumour dataset. The curve for summed PCR
replicates (plasmid and cell samples) or median tumours (by Hoover index) in a group is highlighted. The black line is the line of equality. D Hoover index of each sample as a measure of inequality of the read counts for all and NTC gRNAs. E Letter-value plot of log normalised
counts per million (log-ncpm) for all gRNAs in cell and tumour samples (zeroes given pseudocount of 0.5). Counts for plasmid and cell samples
were summed from two PCR replicates prior to normalisation. Sample name refers to group, animal number and flank position (e.g. A1L
represents a tumour on the left flank of mouse 1 from group A). Fig. 4
Assessing gRNA-driven selection in HCT116/54C in vivo screens. A Ratio of counts for the gRNA at the 90th count percentile among
all gRNAs to counts for the NTC gRNA at the 90th count percentile. The bar indicates mean ± SEM. B Distribution of log2 normalised cpm of
the top 16 gRNAs (by p-value control versus 6-thioguanine) targeting genes expected to be involved in 6-thioguanine resistance in the
tumour samples. The selected genes were HPRT1, NUDT5 and 23 genes in the KEGG mismatch repair geneset (6-TG = 6-thioguanine,
evo = evofosfamide). Lines are the average log cpm calculated with aveLogCPM (prior count of 0.5), and statistics are for the no drug versus
6-thioguanine comparison using the edgeR exactTest function with dispersion estimated from large tumour samples only. C Variation in
counts of four gRNAs across samples in the large tumour dataset. The four gRNAs represent those with the highest and 10th highest
maximum log normalised cpm across all samples for all or NTC gRNAs. D Variation in counts of the six gRNAs in the library targeting CXCL2
across samples in the large tumour dataset. For C, D, the numbers above each individual targeting gRNA represent previously reported
estimates of guide activity [14], with scores approaching 1 representing highly effective gRNAs and those approaching 0 representing poorly
performing gRNAs. Fig. 4
Assessing gRNA-driven selection in HCT116/54C in vivo screens. A R Fig. 4
Assessing gRNA-driven selection in HCT116/54C in vivo screens. A Ratio of counts for the gRNA a Fig. 4
Assessing gRNA-driven selection in HCT116/54C in vivo screens. A Ratio of counts for the gRNA at the 90th count percentile among
all gRNAs to counts for the NTC gRNA at the 90th count percentile. T.W. Lee et al. 1617 Fig. 3
Whole genome in vivo screens for HCT116/54C GeCKOv2 libraries in small and large tumours. A HCT116/54C GeCKO tumour
growth after the commencement of drug treatment at day 14 (arrow) (mean ± SEM; n = 8–10). B Percentage of all or NTC gRNAs detected for
HCT116/54C GeCKO cells (inoculum or cultured an additional 14 or 38 days after inoculation) and HCT116/54C GeCKO tumours collected at
14 days, 38 days with no drug, 42 days with 6-thioguanine (6-TG) or 43 days with evofosfamide (evo). Replicate cell samples are PCR replicates
from the same gDNA sample (n = 2 each); tumour replicates are individual tumours grown bilaterally (n = 8 for 14 d and evo; n = 10 for 38 d
and 6-TG). The bar indicates mean ± SEM. C Lorenz curves to show the distribution of all gRNA read counts. The curve for summed PCR
replicates (plasmid and cell samples) or median tumours (by Hoover index) in a group is highlighted. The black line is the line of equality. D Hoover index of each sample as a measure of inequality of the read counts for all and NTC gRNAs. E Letter-value plot of log normalised
counts per million (log-ncpm) for all gRNAs in cell and tumour samples (zeroes given pseudocount of 0.5). Counts for plasmid and cell samples
were summed from two PCR replicates prior to normalisation. Sample name refers to group, animal number and flank position (e.g. A1L
represents a tumour on the left flank of mouse 1 from group A). 1 Fig. 3
Whole genome in vivo screens for HCT116/54C GeCKOv2 libraries in small and large tumours. A HCT116/54C GeCKO tumour
growth after the commencement of drug treatment at day 14 (arrow) (mean ± SEM; n = 8–10). B Percentage of all or NTC gRNAs detected for
HCT116/54C GeCKO cells (inoculum or cultured an additional 14 or 38 days after inoculation) and HCT116/54C GeCKO tumours collected at
14 days, 38 days with no drug, 42 days with 6-thioguanine (6-TG) or 43 days with evofosfamide (evo). Replicate cell samples are PCR replicates
from the same gDNA sample (n = 2 each); tumour replicates are individual tumours grown bilaterally (n = 8 for 14 d and evo; n = 10 for 38 d
and 6-TG). The bar indicates mean ± SEM. C Lorenz curves to show the distribution of all gRNA read counts. Including only the large tumours in the analysis resulted in the
detection of a more realistic number of gRNAs as being selected Cancer Gene Therapy (2023) 30:1610 – 1623 T.W. Lee et al. T.W. Lee et al. 1618 biased the estimated dispersion downwards relative to what
would be applicable for the large tumours, resulting in failure to
control type I error. (approximately 2000 in each direction for 6-thioguanine and 0 for
evofosfamide; FDR < 0.1; Supplemental Data Files 1 and 3). This
was due to a change in the dispersion estimates—common
dispersion was 4.8 for the dataset including small tumours, and 8.2
for the large tumours only. In the first analysis, the inclusion of
small tumours, which had lower variability in counts, effectively yp
Although a number of gRNAs were detected at FDR < 0.1 in the
large tumour dataset for 6-thioguanine, gene-level analysis of these
gRNA-level data by RRA [38] detected no gene hits at FDR < 0.1 for Cancer Gene Therapy (2023) 30:1610 – 1623 Count dispersion increases with growth time and is much
greater in tumour samples To obtain a statistical measure of the level of random variation in
gRNA counts in different sample groups, we used edgeR to
estimate the negative binomial dispersion for different subsets of
our dataset. To simplify comparisons, we determined the common
dispersion, which assumes all gRNAs have the same dispersion,
and took the square root of this to estimate the biological
coefficient of variation (BCV; square root of common dispersion)
for each subset. We performed this analysis on both technical
replicates and biological replicates. Among technical replicates,
the BCV across sequencing runs for the same sample was low at
0.012 (Fig. 5A), which is expected given this variation should
follow a Poisson distribution. BCV of a similar magnitude was
obtained for PCR replicates of the GeCKOv2 plasmid sample
(0.022), but interestingly the BCV for PCR replicates of various
samples of HCT116/54C GeCKO cells was greater (0.091–0.164),
suggesting amplification bias during the PCR process used for
gRNA readout was contributing to count variation. Several
HCT116/54C GeCKO cell samples collected at different times were
available, with culture periods from the initial post-transduction
sample (‘time zero’) varying from 16–55 d. When all cell samples
(n = 5) were analysed as a single group, the BCV was 0.489, while
cell samples cultured ~30 d (28–31 d, n = 2) had a BCV of 0.392
and those cultured ~16 d (16–17 d, n = 2), 0.208, showing that
dispersion was increasing with growth time. The BCV of even small
tumour samples was considerably greater at 0.84–1.18, while for
the large tumours, it increased further to 2.81-3.17. These
increases in dispersion with growth in both the cell and tumour
samples are consistent with the widening of the count distribution
that occurred with increased growth time (Fig. 3E). We also
estimated the count dispersion for various combinations of
sample groups to illustrate the risk of underestimating dispersion
when a lower dispersion group is included among higher
dispersion groups. The BCV with all large tumour groups was
2.83, but when 14 d tumours were included, this decreased to
2.16, further decreasing to 1.92 if the pilot tumours were also
included. Combining cell samples and all tumours led to
additional decreases in the BCV estimate (Fig. 5A). Circles and solid lines indicate the curve
obtained from the dispersion estimate from n = 3 tumours; the median across 100 simulated datasets is plotted. The dark grey area represents
the lower and upper quartiles, and the light grey area is the range. The squares and dashed line indicate the power curve when using the
maximum dispersion estimate across 100 simulated datasets from n = 10 (small tumours) or n = 20 (large tumours); cln/gRNA: clones/gRNA. 1 is consistent with the variation in counts being driven by
stochastic effects instead of gRNA-editing effects. either 6-TG or evofosfamide compared to untreated (Supplemental
Data Files 2 and 4). To further evaluate the performance of the
screen, we assessed the enrichment of gRNAs targeting well-
characterised 6-TG sensitivity genes HPRT1 and NUDT5 [44], as well
as those in the mismatch repair pathway [7], in treated tumours. The
top gRNAs (by FDR) targeting this subset of genes were either
enriched or depleted in treated tumours vs. controls rather than
being predominately enriched (Fig. 4B). For example, one gRNA
targeting NUDT5 was depleted (A32983 log2 FC −7.9, FDR = 0.078),
but another was enriched (A32982 log2 FC 6.1, FDR = 0.11). In
addition, there was large variability in gRNA counts and frequent
incidence of zero counts across all tumours, such that any apparent
enrichment in one group versus another was largely driven by a
small number of tumours having very high counts despite other
samples having much lower counts (potentially zero). Count dispersion increases with growth time and is much
greater in tumour samples p
g
(p
y
)
The high count dispersion, together with the pattern of read
counts among individual tumours for a particular gRNA, suggest a
strong random component of clonal expansion within each
tumour. Individual clones (with gRNAs as barcodes) potentially
expand to a very high frequency in an apparently random fashion,
which masks any potential effects of selection. Indeed, we found
that the identities of the top gRNAs were different in each sample
(Fig. S2A), and Spearman correlation analysis failed to identify any
grouping of large tumours by treatment group or overall (Fig. S2B). To further demonstrate this, we plotted the read counts of
the gRNAs with the highest (CXCL12 gRNA #B11840) and 10th
highest (SLC18A3 gRNA #A44491) log-ncpm across all samples, as
well as the NTC gRNAs with the highest (NTC gRNA #0404) and
10th highest (NTC #0161) log-ncpm across all samples. The read
counts of these four gRNAs varied widely across large tumour
samples (Fig. 4C). For instance, the log-ncpm for CXCL12 gRNA
#B11840 in one 6-TG-treated tumour was 26.5, while zero counts
were detected in another 6-TG-treated tumour. This wide variation
suggests largely random expansion of clones within these
tumours. In smaller tumours, the counts were less variable but
were still unusually high or low in certain samples, indicating a
degree of random clonal expansion was already present in these
smaller tumours. To confirm this variation applied across all gRNA
targeting the same gene, we also investigated all gRNAs targeting
CXCL12 and observed a similar level of variation between samples
as we had seen for CXCL12 gRNA #B11840 (Fig. 4D). Estimated
guide activities (in the range 0–1; ref. [14]) for the CXCL12 gRNAs
vary from 0.31 to 1.00. Although the CXCL12 gRNA with the most
variable counts (#B11840) was the one with the highest estimated
activity (1.00) while the least active guide (#A11852; 0.31) had the
most dropouts, the other guides with estimated activities in the
range 0.33–0.89 showed a similar pattern of count variability. This T.W. Lee et al. 1619 Fig. 5
Count dispersion and statistical power in HCT116/54C whole genome and simulated libraries of reduced size. A Biological
coefficient of variation (BCV) estimated in edgeR for different subsets of samples. Data points represent different sample groups, and lines
represent combinations of sample groups. Seq Reps: Sequencing replicates (n = 2) of the same library (14 d tumour) produced by PCR. PCR
Reps: PCR replicates of the plasmid DNA (Pls) or the same genomic DNA samples from cultured HCT116/54C GeCKO cells (Cells), n = 2 each. Cells: Replicate HCT116/54C GeCKO cell samples cultured in parallel from the time zero sample for 16–17 d (~16 d; n = 2), 28–31 d (~30 d;
n = 2), or all samples combined (n = 5), including one sample cultured for 55 d; any PCR replicates were collapsed by summing prior to
calculating BCV for these biological replicates. Tumours: Pilot study tumours for HCT116/54C GeCKO in NSG (NSG, n = 3) and NIH-III mice (NIH;
n = 3) and UT-SCC-74B GeCKO in NSG mice (74B, n = 3). Larger study tumours collected early (14 d, n = 8), control-treated tumours (38 d,
n = 10), 6-thioguanine-treated tumours (6-TG; n = 10) and evofosfamide-treated tumours (evo; n = 8). B Estimates of the median number of
clones present in each sample from the pilot and larger study, based on the estimated probability of survival of cells with neutral (NTC) gRNAs,
and the median number of cells per gRNA. C Estimates of BCV in simulated datasets of reduced library size by random binning and/or
subsampling gRNAs and samples from small tumour data (NSG pilot + 14 d). Boxplots show the distribution of the BCV estimates for
100 simulated datasets for n = 3, n = 10 or n = 20 tumours and indicate the number of gRNAs. D Estimates of BCV in simulated datasets of
reduced library size from large tumour data (untreated, 6-TG and evo; 38–43 d). The number of clones/gRNA in C and D is estimated based on
the median number of clones/gRNA for a full library multiplied by the binning factor. E Power curves determined from the common
dispersion estimates of simulated datasets at a log2 effect size of 2 for small and large tumours. Simulations show reduced count dispersion in tumour
samples with reduced gRNA library sizes This suggests that when the sample
size is estimated from a smaller pilot dataset, a conservative
sample size inflating factor of 2 is needed to ensure the correct
level of statistical power in a full dataset. When using the more
precise n = 10 dispersion estimates for small tumours, our
simulations showed that at a log2 effect size of 2, a median
estimate of 35 tumours (range 34–37 across simulated datasets) is
required to achieve power of 0.8 with 100,000 gRNAs, progres-
sively reducing to 3 tumours (range: 3–4) with 2000 gRNAs. We
estimate that there would be 170 clones/gRNA when using a
library of 2000 gRNAs. For large tumours (dispersion estimates
from n = 20 tumours) and 4000–100,000 gRNAs, >50 tumours per
group were required to achieve power of 0.8 (Fig. 5E; Fig. S3A;
Table S5) at effect size of 2, falling to 20–50 tumours at 500–2000
gRNAs, and <20 tumours at library sizes of <500 gRNAs. Although
our power calculations indicate very small libraries are needed to
achieve good power with feasible group sizes (<20–30) at this
effect size, these can also be interpreted in the context of the
number of clones present: we estimate ~100–400 clones/gRNA
will survive in libraries of <500 gRNAs in large tumours. These
estimates highlight how the reductions in count dispersion,
achieved through the use of a smaller gRNA library, substantially
reduce the sample sizes needed to achieve good statistical power. g
These estimated numbers of clones/gRNA suggest very low
effective in vivo coverage of our library. Improving coverage by
increasing the number of cells inoculated per gRNA would result in
greater averaging of the random effects on growth and survival,
resulting in reduced count dispersion, thereby increasing statistical
power to detect gRNA selection. Although there was limited scope
to increase the total number of cells inoculated, the number of cells
inoculated per gRNA could be increased by reducing the total
library size. Simulations show reduced count dispersion in tumour
samples with reduced gRNA library sizes p
g
y
The GeCKOv2 whole genome gRNA library used in this study
consists of 119 461 unique gRNAs. With 107 cells inoculated per Cancer Gene Therapy (2023) 30:1610 – 1623 T.W. Lee et al. 1620 tumour, there was an average of 84 cells/gRNA. However, not all
these cells will survive to form a clone. To approximate the number
of clones/gRNA, we used a binomial model to estimate the overall
probability of a cell with neutral (NTC) gRNA surviving in a tumour to
form a clone based on the pattern of gRNAs detected (at a given
detection level) and the count distribution of the cell inocula. For
small NSG tumours, the estimated probability of a cell surviving to
form a clone was 0.034–0.10 (1 in 10–30), which implies a median of
2.3–7.0 clones/gRNA (Fig. 5B). In large tumours, the probability of
clones continuing to survive decreases to 0.0022–0.0074 (1 in
134–459), implying a number of surviving clones/gRNA of 0.15–0.52
(Fig. 5B). If we assume that the number of clones/gRNA is a more
important metric for coverage in in vivo screens compared to cells/
gRNA, these estimates suggest that the effective in vivo coverage of
our library was several orders of magnitude less than typically
recommended for in vitro screens (minimum coverage of at least
100 cells/gene is recommended; ref. [45]). tumour growth period. BCV estimates were less precise when
determined from a small number of pilot samples, as indicated by
the greater range, particularly at the lower end, when estimated
from n = 3 compared to using a larger number of samples (n = 10
or n = 20), coupled with a tendency for the median to be lower at
n = 3 (Fig. 5C, D). ( g
,
)
To estimate the consequence of varying count dispersion on
downstream statistical analysis, we conducted power and sample
size calculations using these common dispersion estimates (Fig. 5E; Fig. S3; Table S5). When dispersion was estimated from n = 3
tumours, the estimates of the sample size required to achieve
0.8 statistical power had a greater range and lower median, with
the minimum across simulations at n = 3 being approximately 1.5-
to 2-fold less than that of the most conservative estimates
(maximum
across
simulations)
with
n = 10/n = 20
tumours
(except
where
the
estimated
sample
sizes
required
were
themselves close to n ≤3). DISCUSSION
I
i
CRISP In vivo CRISPR/Cas9 screens offer the opportunity to identify
genes responsible for a specific phenotype in response to
selective pressure, while maintaining the complex multicellular
interactions of the tumour microenvironment. In this study, we
investigated several parameters that could be optimised when
conducting these screens, including cell line, host mouse strain,
tumour collection time and gRNA library size. Our low TD50
HCT116/54C line retained >99% gRNA representation in cultured
cells and had much higher gRNA representation than the
moderate TD50 cell line UT-SCC-74B when GeCKO-transduced
cells were inoculated into NSG mice at 107 cells. Although not
definitive since only two models were used, our data does suggest
that using a conducive mouse host and cell line with a low TD50
and, therefore, potentially a high frequency of tumour-initiating
cells can lead to high gRNA representation on tumour initiation. Despite the high gRNA representation at tumour initiation with
our HCT116/54C GeCKO tumour model, a considerable loss in
gRNA representation was observed as tumours were grown to
>1 cm3. The loss of representation was accompanied by a
substantial increase in read count inequality that was highly
variable between tumours and observed with both targeting and
non-targeting gRNA, suggesting that stochastic differences in
clonal growth and survival rather than gRNA-induced selection
were the dominant driver. These clonal dynamics would include
both random clonal expansion (where some clones have a growth
advantage) and random clonal dropout (where some clones have In vivo CRISPR/Cas9 screens offer the opportunity to identify
genes responsible for a specific phenotype in response to
selective pressure, while maintaining the complex multicellular
interactions of the tumour microenvironment. In this study, we
investigated several parameters that could be optimised when
conducting these screens, including cell line, host mouse strain,
tumour collection time and gRNA library size. Our low TD50
HCT116/54C line retained >99% gRNA representation in cultured
cells and had much higher gRNA representation than the
moderate TD50 cell line UT-SCC-74B when GeCKO-transduced
cells were inoculated into NSG mice at 107 cells. Although not
definitive since only two models were used, our data does suggest
that using a conducive mouse host and cell line with a low TD50
and, therefore, potentially a high frequency of tumour-initiating
cells can lead to high gRNA representation on tumour initiation. Simulations show reduced count dispersion in tumour
samples with reduced gRNA library sizes To assess the effects of using a smaller gRNA library for
in vivo screens, we simulated smaller gRNA libraries by randomly
combining the gRNA counts in our full-size library into bins of
2–1600 gRNAs, followed by subsampling gRNAs (and samples) to
100,000 (unbinned), 50,000, 25,000, 10,000, 4000, 2000, 1000, 500,
250, 125 or 62 gRNAs; these represented datasets with coverage
84–130,000 cells/gRNA, respectively, but with much lower coverage
in terms of clones/gRNA: 3.4–5400 clones/gRNA in small tumours,
0.27–420 clones/gRNA in large tumours, based on our estimates of
the number of clones/gRNA in our full library. We reasoned that our
binned counts would mimic the random characteristics of clonal
expansion in smaller libraries, as clones with different gRNAs in the
larger library would be largely equivalent (in terms of random
characteristics) to different clones that receive the same gRNA in a
smaller library. Any signal due to the gRNAs themselves, which we
have already established was small relative to the random clonal
expansion effect (Fig. 4), was further averaged out by the random
nature of the binning, particularly among bins with a greater
number of gRNAs, as well as subsampling to reduce dependence on
any particular sample or gRNA. Cancer Gene Therapy (2023) 30:1610 – 1623 DISCUSSION
I
i
CRISP In the unequal read
count distributions of the tumour samples, the majority of reads
were from only a small fraction of gRNAs, with up to 1.4–17% of all
reads from a single gRNA in the large tumours, probably from a
single expanded clone. The random expansion of individual clones
has also been reported as a confounding factor in cell-based
CRISPR/Cas9 screens [47] and is common in xenograft models
[46, 48]. Clonal expansion can also lead to apparent dropout due
to sampling effects (sampling zeroes; ref. [43]), where clones that
remain present in the population but are less abundant become
difficult to detect due to repeated sampling of the expanded
clones. genome in vivo screens, we found that, when sufficient detail
was provided, most datasets resembled that of the current study
in terms of loss of representation, read count inequality and highly
expanded counts of a small number of clones, particularly in larger
tumours [28, 29, 31, 32, 56–58]. Two studies, however, report
considerably
higher
gRNA
representation
and
lower
count
inequality than our model [30, 33]. In both of these studies,
tumours were inoculated at 3 × 107 cells into mice, a 3-fold
increase on our inoculum. This extends to a ~6-fold increase in
cells/gRNA (~450 vs. ~84 in our study) as they used the GeCKOv2A
half-library, and this may have contributed to greater averaging
across clones in tumours and a reduction in count variance
compared to our study. However, it is likely other variables, such
as improved tumour growth characteristics due to the particular
cell line/host combination used (i.e. more tumour-initiating cells),
also contributed to the significantly better-quality data compared
to all the other long-term whole genome in vivo screens. Indeed,
in our own data, a considerable difference in performance was
observed between the HCT116/54C GeCKO and UT-SCC-74B
GeCKO models, with the use of NSG over NIH-III hosts providing
only a minor improvement. Although there were some indications of gRNA-driven selection
among our tumour samples, ultimately, random clonal dynamics
within the tumours prevented us from identifying drug sensitivity
genes in our study, due to the high count dispersion. Indeed, the
BCV estimates we observed of about 1 for small tumours and
approaching 3 for large tumours vastly exceed typical values
observed in count data from RNAseq [49]. DISCUSSION
I
i
CRISP Given the high
dispersion, we ran simulations to identify the parameters our
model would require to have 80% statistical power to detect
gRNA-mediated gene selection. Our simulated datasets indicated
that count variance could be reduced by reducing library size and
increasing averaging across clones, increasing statistical power to
a level where gRNA-driven selection (log2 fold-change 2) is
detectable in a study of feasible size with 20,000 or fewer gRNAs. In large tumours, however, our simulations suggested very small
library sizes of ≤500 gRNAs are needed to achieve similar power at
the same effect size when large groups (n ~ 20–30) are used. This
suggests that the improvements made by using a smaller library
are rapidly diminished by cumulative time/growth-dependent
stochastic effects. To overcome this strong time-dependent effect,
initiating tumour treatment when tumours are small (~150 mm3)
and collecting tumours 7–14 days after treatment when tumours
at most are moderate in size (<~750 mm3) may allow count
variance
to be
adequately
constrained
to
retain
sufficient
statistical power to detect smaller treatment effects. When
assessed in terms of the number of clones/gRNA, our simulations
suggest a rule of thumb when choosing a library size is coverage
in the range of 50–400 clones/gRNA, which is similar to the
suggested coverage of 25–250 cells/gRNA (100–1000 cells/gene)
for in vitro screens [45, 50], although expressed in terms of clones
instead of cells. In terms of likely effect sizes, the mean estimated
level of negative selection (for essential genes) in our large
tumours was low (−0.39 log2 fold-change) but somewhat greater
than in vitro samples cultured over a similar period of 40 days
(−0.19 log2 fold-change; Supplemental Results; Fig. S8), suggest-
ing a similar magnitude of selection would be observed in in vivo
screens as that observed in in vitro screens when coverage is
sufficient, and the screens are adequately powered. Although this
estimate was lower than the effect sizes used in our power
calculations, it represents an average value rather than the effect
size that would occur with the most selective genes and the most
active
gRNAs. In
addition,
this
number
likely
reflects
the
performance of the GeCKOv2 library, which is known to be poorer
than more recent libraries [44], and is not suitable to be
generalised across gRNA libraries. DISCUSSION
I
i
CRISP The use of gRNAs with high
targeting efficiency [44, 51] is likely to be important to maximise
the effect sizes and ensure success in in vivo screening. A
number
of
successful
transplantable
in
vivo
CRISPR/ only a minor improvement. Our study provides several insights regarding the underlying cell
growth characteristics in in vivo tumour xenograft screens with
implications for the analyses of the resulting data. Firstly, we show
that count dispersion is dependent on sample type (cells versus
tumours) and increases with growth time in both cell and tumour
samples. These observations have an intuitive explanation—count
dispersion is driven by random clonal dynamics, and the extent of
this effect is expected to be cumulative over time and greater in
tumours due to the founder effect and stronger microenviron-
mental differences between clones. Although not unexpected, we
are not aware that this issue has been highlighted previously. We
also show that the variable nature of count dispersion across
samples poses a risk of improperly controlling statistical error when
samples of mixed dispersion are combined (e.g. small and large
tumours,
cells
cultured
from
significantly
different
periods). Methods developed to analyse sequencing count data, including
methods originally developed for RNAseq such as edgeR [37, 49]
and the negative binomial method for gRNA counts in MAGeCK
[38], typically allow for heterogeneity in variance among different
genes/gRNAs by modelling a mean-variance trend but do not allow
for heteroskedasticity among sample groups. While this may not be
an issue in RNAseq data where counts measure gene expression, we
believe it warrants further attention in analyses of CRISPR/Cas9-
screen gRNA data, given random clonal dynamics are a potentially
large source of heteroskedasticity between sample groups, even for
purely in vitro screens. As a minimum, care should be taken when
analysing these data to ensure all groups have similar variances. If
required, tools that separate the estimation of the dispersion from
statistical tests, such as edgeR, could be used to perform
conservative statistical analyses where dispersion is estimated from
the group(s) with the most variance rather than across all groups. In
addition, the use of linear model-based voom/limma analysis with
sample-specific weights [59] may improve analyses by modelling
sample-specific variation; we did not test this method in the present
study as our data contained a high proportion of zero counts, which
we considered to be unsuitable for linear model analysis of counts. DISCUSSION
I
i
CRISP To assess the effects of a smaller gRNA library on count dispersion
and statistical power, we estimated the common dispersion using
edgeR following binning/subsampling on our dataset. The disper-
sion was estimated with a varying number of tumour samples to
evaluate the degree to which the dispersion that would apply to a
large dataset could be estimated from only a small number of
samples; such a situation would occur, for example, when a pilot
experiment is conducted to inform power calculations for a later
full-sized experiment. For small tumours, our simulations showed
that a reduction in BCV to approximately 0.5 could be achieved with
10,000 gRNAs, a further reduction to about 0.3 with 2000 gRNAs,
which are of a similar BCV magnitude to samples of HCT116/54C
GeCKO cells, and below 0.1 with very small library sizes of <200
gRNAs (Fig. 5C). When these library sizes were considered in terms
of the estimated number clones/gRNA, BCV values of 0.15–0.3 were
achievable with ~150–700 clones/gRNA in small tumours. For large
tumours, a reduction in gRNA library size to 2000 or less reduced the
BCV below 1.5, similar to in small tumours with a full library, while a
very small library size of 62 gRNA was required to achieve a similar
BCV to in cells of approximately 0.5 (Fig. 5D). On a per clone basis,
dispersion as estimated by BCV was also higher in large tumour
samples compared to small tumour samples, which is consistent
with random clonal dynamics being cumulative throughout the g
g
Despite the high gRNA representation at tumour initiation with
our HCT116/54C GeCKO tumour model, a considerable loss in
gRNA representation was observed as tumours were grown to
>1 cm3. The loss of representation was accompanied by a
substantial increase in read count inequality that was highly
variable between tumours and observed with both targeting and
non-targeting gRNA, suggesting that stochastic differences in
clonal growth and survival rather than gRNA-induced selection
were the dominant driver. These clonal dynamics would include
both random clonal expansion (where some clones have a growth
advantage) and random clonal dropout (where some clones have Cancer Gene Therapy (2023) 30:1610 – 1623 T.W. Lee et al. 1621 a survival disadvantage). Our data suggests, however, that it is
stochastic clonal expansion, likely expedited by the genetic
bottleneck of tumour initiation [46], that is a more important
limiting factor for in vivo CRISPR/Cas9 screens. Cancer Gene Therapy (2023) 30:1610 – 1623 DISCUSSION
I
i
CRISP Regardless, a
pilot study (n = 3) of the chosen cell line and host should be
conducted at the candidate tumour collection timepoint (not done in
the current study) prior to commencing a full-sized experiment. Power calculations can then be performed using these pilot data to
estimate the sample size needed to detect treatment effects at the
gRNA level. Here, it is worth noting that our simulated datasets
suggest a sample size inflating factor of 2 may be needed to provide a
conservative estimate due to imprecise variance estimates from
limited data (an expected issue when using pilot data to estimate
power for a main experiment; ref. [62]). If the estimated sample size
proves infeasible, it would be preferable to make changes to the
screen design to improve power (library size, cell line, host) rather
than proceeding with an underpowered in vivo screen, for both
resource and ethical reasons. 5. Haley B, Roudnicky F. Functional genomics for cancer drug target discovery. Cancer Cell. 2020;38:31–43. 6. Thomsen MK. Application of CRISPR for in vivo mouse cancer studies. Cancers
2022;14:5014. 7. Wang T, Wei JJ, Sabatini DM, Lander ES. Genetic screens in human cells using the
CRISPR-Cas9 system. Science. 2014;343:80–4. 8. Shalem O, Sanjana NE, Hartenian E, Shi X, Scott DA, Mikkelsen TS, et al. Genome-
scale CRISPR-Cas9 knockout screening in human cells. Science 2014;343:84–7. 9. Zhou Y, Zhu S, Cai C, Yuan P, Li C, Huang Y, et al. High-throughput screening of a
CRISPR/Cas9
library
for
functional
genomics
in
human
cells. Nature
2014;509:487–91. 10. Hart T, Chandrashekhar M, Aregger M, Steinhart Z, Brown KR, MacLeod G, et al. High-resolution CRISPR screens reveal fitness genes and genotype-specific cancer
liabilities. Cell 2015;163:1515–26. 11. Wang T, Birsoy K, Hughes NW, Krupczak KM, Post Y, Wei JJ, et al. Identification
and characterization of essential genes in the human genome. Science
2015;350:1096–101. 12. Wang T, Yu H, Hughes NW, Liu B, Kendirli A, Klein K, et al. Gene essentiality
profiling reveals gene networks and synthetic lethal interactions with oncogenic
Ras. Cell 2017;168:890–903.e15. 13. Behan FM, Iorio F, Picco G, Gonçalves E, Beaver CM, Migliardi G, et al. Prioritization
of cancer therapeutic targets using CRISPR–Cas9 screens. Nature 2019;568:511–6. 14. Meyers RM, Bryan JG, McFarland JM, Weir BA, Sizemore AE, Xu H, et al. Com-
putational correction of copy number effect improves specificity of CRISPR–Cas9
essentiality screens in cancer cells. Nat Genet. 2017;49:1779–84. 15. DISCUSSION
I
i
CRISP Bester AC, Lee JD, Chavez A, Lee YR, Nachmani D, Vora S, et al. An integrated
genome-wide CRISPRa approach to functionalize lncRNAs in drug resistance. Cell
2018;173:649–664.e20. 16. MacLeod G, Bozek DA, Rajakulendran N, Monteiro V, Ahmadi M, Steinhart Z, et al. Genome-wide CRISPR-Cas9 screens expose genetic vulnerabilities and mechan-
isms
of
temozolomide
sensitivity
in
glioblastoma
stem
cells. Cell
Rep. 2019;27:971–986.e9. 17. Wei L, Lee D, Law CT, Zhang MS, Shen J, Chin DWC, et al. Genome-wide CRISPR/
Cas9 library screening identified PHGDH as a critical driver for Sorafenib resis-
tance in HCC. Nat Commun. 2019;10:4681. 18. Lau M-T, Ghazanfar S, Parkin A, Chou A, Rouaen JR, Littleboy JB, et al. Systematic
functional identification of cancer multi-drug resistance genes. Genome Biol. 2020;21:27. In summary, we report that the main limiting factor for in vivo
CRISPR/Cas9 screens in detecting gRNA-driven changes among
treatment groups is variable clonal dynamics within tumours
leading to high count variance. This can be addressed to a degree
by cell line and mouse host choice. We found that count variance
increased with increasing growth time, likely due to random
differences in cell growth and survival in the tumours. In large
tumours of our model, count dispersion accumulated to a very
high level, with the populations dominated by relatively few
individual clones. Using simulated binned datasets, we showed
that count dispersion can be reduced by the use of small tumours
(or those grown for a short period of time) and greater averaging
using smaller gRNA libraries. Based on these analyses, we
conclude that our xenograft model would have been suitable
for short-medium duration in vivo screens using a more focused
library of up to several thousand gRNAs. These findings will likely
extend to other xenograft models with similar in vivo growth
characteristics. 19. Dhoonmoon A, Schleicher EM, Clements KE, Nicolae CM, Moldovan GL. Genome-
wide
CRISPR
synthetic
lethality
screen
identifies
a
role
for
the
ADP-
ribosyltransferase PARP14 in DNA replication dynamics controlled by ATR. Nucleic Acids Res. 2020;48:7252–64. 20. Steinhart Z, Pavlovic Z, Chandrashekhar M, Hart T, Wang X, Zhang X, et al. Genome-wide CRISPR screens reveal a Wnt-FZD5 signaling circuit as a druggable
vulnerability of RNF43-mutant pancreatic tumors. Nat Med. 2017;23:60–8. 21. Feng X, Tang M, Dede M, Su D, Pei G, Jiang D, et al. Genome-wide CRISPR screens
using isogenic cells reveal vulnerabilities conferred by loss of tumor suppressors. Sci Adv. 2022;8:eabm6638. 22. DISCUSSION
I
i
CRISP In addition, the characteristics of our data could be used to
parameterise computational tools [50] that model the clonal
dynamics in in vivo screens, allowing more sophisticated in silico
simulations to be carried out to assess the contribution of various
screen parameters and ensure studies are adequately powered. Finally, our study provides a pathway towards a more rational
approach in designing in vivo CRISPR/Cas9 screens for drug sensitivity
genes. The first step in designing a screen is to consider the trade-offs
between library size and resulting statistical power. As we have
shown, smaller libraries can have greater power and are ideal if a
focussed set of genes is being investigated, however may not be A
number
of
successful
transplantable
in
vivo
CRISPR/
Cas9 screens have been reported in the literature. Consistent
with our simulations of the smaller datasets, most of these used
smaller libraries limited to a subset of genes consisting of <10,000
gRNAs, with libraries potentially further subpooled [52–55]. In a
non-exhaustive survey of the literature for previous whole Cancer Gene Therapy (2023) 30:1610 – 1623 T.W. Lee et al. 1622 suitable for more exploratory research. A two-stage screening process
with candidates for in vivo screening first identified within in vitro
screens in simple cultures or more biologically complex 3D spheroid
or organoid cultures [60, 61] could be used if there is no candidate-
focused gene set initially available. If a full genome library in vivo is
required, apart from more recent optimised whole-genome libraries
with higher targeting efficiency (e.g. Brunello or Brie) [44], a further
optimised “minimal” library (~38,000 gRNAs) could be used to
provide some reduction in library size [51]. Once the initial candidate
strategy is chosen, it may be beneficial to test multiple cell lines and
animal hosts to identify the combination that provides the best
tumour growth characteristics in pilot tumour growth experiments
(n = 3 tumours), similar to those performed in the current study. The
resulting gRNA counts should be evaluated not only in terms of
representation but also count inequality and variance, with the
combination with the lowest variance preferred to increase the
chances of detecting gRNA-driven selection. It may also be useful to
evaluate different tumour collection timepoints to ascertain the
degree to which count variance increases over time. DATA AVAILABILITY The gRNA count dataset, analysis code and other associated files are available in
Figshare (https://doi.org/10.17608/k6.auckland.23037053). 27. Wang G, Chow RD, Ye L, Guzman CD, Dai X, Dong MB, et al. Mapping a functional
cancer genome atlas of tumor suppressors in mouse liver using AAV-
CRISPR–mediated direct in vivo screening. Sci Adv. 2018;4:5508. 28. Chen S, Sanjana NE, Zheng K, Shalem O, Lee K, Shi X, et al. Genome-wide CRISPR
screen
in
a
mouse
model
of
tumor
growth
and
metastasis. Cell
2015;160:1246–60. DISCUSSION
I
i
CRISP Patel SJ, Sanjana NE, Kishton RJ, Eidizadeh A, Vodnala SK, Cam M, et al. Identi-
fication of essential genes for cancer immunotherapy. Nature 2017;548:537–42. 23. Sheffer M, Lowry E, Beelen N, Borah M, Amara SN-A, Mader CC, et al. Genome-
scale screens identify factors regulating tumor cell responses to natural killer
cells. Nat Genet. 2021;53:1196–206. 24. Junttila MR, De, Sauvage FJ. Influence of tumour micro-environment hetero-
geneity on therapeutic response. Nature 2013;501:346–54. 25. Singleton DC, Macann A, Wilson WR. Therapeutic targeting of the hypoxic tumour
microenvironment. Nat Rev Clin Oncol. 2021;18:751–72. 26. Chow RD, Guzman CD, Wang G, Schmidt F, Youngblood MW, Ye L, et al. AAV-
mediated direct in vivo CRISPR screen identifies functional suppressors in glio-
blastoma. Nat Neurosci. 2017;20:1329. REFERENCES 1. Malone ER, Oliva M, Sabatini PJB, Stockley TL, Siu LL. Molecular profiling for
precision cancer therapies. Genome Med. 2020;12:8. 1. Malone ER, Oliva M, Sabatini PJB, Stockley TL, Siu LL. Molecular profiling for
precision cancer therapies. Genome Med. 2020;12:8. 29. Song C-Q, Li Y, Mou H, Moore J, Park A, Pomyen Y, et al. Genome-wide CRISPR
screen identifies regulators of mitogen-activated protein kinase as suppressors of
liver tumors in mice. Gastroenterology 2017;152:1161–1173.e1. 2. Dittrich C. Basket trials: from tumour gnostic to tumour agnostic drug develop-
ment. Cancer Treat Rev. 2020;90:102082. 2. Dittrich C. Basket trials: from tumour gnostic to tumour agnostic drug develop-
ment. Cancer Treat Rev. 2020;90:102082. 30. Yau EH, Kummetha IR, Lichinchi G, Tang R, Zhang Y, Rana TM. Genome-wide
CRISPR screen for essential cell growth mediators in mutant KRAS colorectal
cancers. Cancer Res. 2017;77:6330–9. 3. Murtaza M, Dawson SJ, Tsui DWY, Gale D, Forshew T, Piskorz AM, et al. Non-
invasive analysis of acquired resistance to cancer therapy by sequencing of
plasma DNA. Nature 2013;497:108–12. 31. Rushworth LK, Harle V, Repiscak P, Clark W, Shaw R, Hall H, et al. In vivo CRISPR/
Cas9 knockout screen: TCEAL1 silencing enhances docetaxel efficacy in prostate
cancer. Life Sci Alliance. 2020;3:e202000770. 4. La Thangue NB, Kerr DJ. Predictive biomarkers: a paradigm shift towards per-
sonalized cancer medicine. Nat Rev Clin Oncol. 2011;8:587–96. Cancer Gene Therapy (2023) 30:1610 – 1623 ADDITIONAL INFORMATION 49. McCarthy DJ, Chen Y, Smyth GK. Differential expression analysis of multifactor
RNA-Seq experiments with respect to biological variation. Nucleic Acids Res. 2012;40:4288–97. Supplementary information The online version contains supplementary material
available at https://doi.org/10.1038/s41417-023-00664-5. 50. Nagy T, Kampmann M. CRISPulator: a discrete simulation tool for pooled genetic
screens. BMC Bioinform. 2017;18:347. Correspondence and requests for materials should be addressed to Tet Woo Lee or
Stephen M. F. Jamieson. 51. Gonçalves E, Thomas M, Behan FM, Picco G, Pacini C, Allen F, et al. Minimal
genome-wide human CRISPR-Cas9 library. Genome Biol. 2021;22:40. Reprints and permission information is available at http://www.nature.com/
reprints ACKNOWLEDGEMENTS We acknowledge the contributions and assistance of Purvi Kakadiya and Stefan
Bohlander with the PCR methodology and sequencing, Dan Li and Courtney Lynch
for virus and library preparation, and Avik Shome for assistance with animal studies. 37. Robinson MD, Smyth GK. Small-sample estimation of negative binomial disper-
sion, with applications to SAGE data. Biostatics. 2008;9:321–32. 38. Li W, Xu H, Xiao T, Cong L, Love MI, Zhang F, et al. MAGeCK enables robust
identification of essential genes from genome-scale CRISPR/Cas9 knockout
screens. Genome Biol. 2014;15:554. FUNDING This work was funded by the Auckland Medical Research Foundation (grant
#1115022), the Health Research Council of New Zealand (grants #14/538 and 19/433)
and the University of Auckland Faculty Research Development Fund. Evofosfamide
was supplied by Threshold Pharmaceuticals. Open Access funding enabled and
organized by CAUL and its Member Institutions. 42. Chen L, Reeve J, Zhang L, Huang S, Wang X, Chen J. GMPR: a robust normalization
method for zero-inflated count data with application to microbiome sequencing
data. PeerJ 2018;6:e4600. 43. Silverman JD, Roche K, Mukherjee S, David LA. Naught all zeros in sequence
count data are the same. Comput Struct Biotechnol J 2020;18:2789–98. 44. Doench JG, Fusi N, Sullender M, Hegde M, Vaimberg EW, Donovan KF, et al. Optimized sgRNA design to maximize activity and minimize off-target effects of
CRISPR-Cas9. Nat Biotechnol. 2016;34:184–91. T.W. Lee et al. 1623 60. Han K, Pierce SE, Li A, Spees K, Anderson GR, Seoane JA, et al. CRISPR screens in
cancer
spheroids
identify
3D
growth-specific
vulnerabilities. Nature
2020;580:136–41. 60. Han K, Pierce SE, Li A, Spees K, Anderson GR, Seoane JA, et al. CRISPR screens in
cancer
spheroids
identify
3D
growth-specific
vulnerabilities. Nature
2020;580:136–41. 32. Kodama M, Kodama T, Newberg JY, Katayama H, Kobayashi M, Hanash SM, et al. In vivo loss-of-function screens identify KPNB1 as a new druggable oncogene in
epithelial ovarian cancer. Proc Natl Acad Sci USA 2017;114:E7301–10. epithelial ovarian cancer. Proc Natl Acad Sci USA 2017;114:E7 61. Ringel T, Frey N, Ringnalda F, Janjuha S, Cherkaoui S, Butz S, et al. Genome-scale
CRISPR screening in human intestinal organoids identifies drivers of TGF-β
resistance. Cell Stem Cell. 2020;26:431–440.e8. 33. Dai M, Yan G, Wang N, Daliah G, Edick AM, Poulet S, et al. In vivo genome-wide
CRISPR screen reveals breast cancer vulnerabilities and synergistic mTOR/Hippo
targeted combination therapy. Nat Commun. 2021;12:3055. 34. Jamieson SM, Tsai P, Kondratyev MK, Budhani P, Liu A, Senzer NN, et al. Evo-
fosfamide for the treatment of human papillomavirus-negative head and neck
squamous cell carcinoma. JCI Insight. 2018;3:122204. 62. Whitehead AL, Julious SA, Cooper CL, Campbell MJ. Estimating the sample size
for a pilot randomised trial to minimise the overall trial sample size for the
external pilot and main trial for a continuous outcome variable. Stat Methods
Med Res. 2016;25:1057–73. 35. Joung J, Konermann S, Gootenberg JS, Abudayyeh OO, Platt RJ, Brigham MD,
et al. Genome-scale CRISPR-Cas9 knockout and transcriptional activation
screening. Nat Protoc. 2017;12:828–63. 36. Meyer KR, Hopwood LE, Gillette EL. Radiation response and characteristics of a
cell line derived from a mouse mammary adenocarcinoma. Radiat Res. 1978;73:315–29. AUTHOR CONTRIBUTIONS FH, WW and SJ designed the study. TWL performed the experiments. TWL, FH, PT and
CP designed the methodological analyses. TWL and SJ analysed the data. TWL and SJ
wrote the paper. All authors reviewed the manuscript and approved the final version. 39. Zhao S, Li C-I, Guo Y, Sheng Q, Shyr Y. RnaSeqSampleSize: real data based sample
size estimation for RNA sequencing. BMC Bioinform. 2018;19:191. 40. Robinson MD, Oshlack A. A scaling normalization method for differential
expression analysis of RNA-seq data. Genome Biol. 2010;11:R25. 41. Anders S, Huber W. Differential expression analysis for sequence count data. Genome Biol. 2010;11:R106. COMPETING INTERESTS 45. Bock C, Datlinger P, Chardon F, Coelho MA, Dong MB, Lawson KA, et al. High-
content CRISPR screening. Nat Rev Methods Prim. 2022;2:9. The authors declare no competing interests. 46. Ben-David U, Ha G, Tseng YY, Greenwald NF, Oh C, Shih J, et al. Patient-derived
f
d
ifi
l
i
N
G
2017 49 1567 75 46. Ben-David U, Ha G, Tseng YY, Greenwald NF, Oh C, Shih J, et al. Patient-derived
xenografts undergo mouse-specific tumor evolution. Nat Genet. 2017;49:1567–75. xenografts undergo mouse-specific tumor evolution. Nat Genet. 2 ETHICAL APPROVAL 47. Michlits G, Hubmann M, Wu S-H, Vainorius G, Budusan E, Zhuk S, et al. CRISPR-
UMI: single-cell lineage tracing of pooled CRISPR-Cas9 screens. Nat Methods. 2017;14:1191–7. All animal experiments followed procedures approved by the University of Auckland
Animal Ethics Committee (approvals #001190 and #001781) and complied with the
ARRIVE guidelines. UMI: single-cell lineage tracing of pooled CRISPR-Cas9 screens. Nat Methods. 2017;14:1191–7. 48. Eirew P, Steif A, Khattra J, Ha G, Yap D, Farahani H, et al. Dynamics of genomic
clones in breast cancer patient xenografts at single-cell resolution. Nature
2015;518:422–6. © The Author(s) 2023 Reprints and permission information is available at http://www.nature.com/
reprints 52. Manguso RT, Pope HW, Zimmer MD, Brown FD, Yates KB, Miller BC, et al. In vivo
CRISPR screening identifies Ptpn2 as a cancer immunotherapy target. Nature
2017;547:413–8. Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims
in published maps and institutional affiliations. 53. Griffin GK, Wu J, Iracheta-Vellve A, Patti JC, Hsu J, Davis T, et al. Epigenetic
silencing by SETDB1 suppresses tumour intrinsic immunogenicity. Nature
2021;595:309–14. 54. Yamauchi T, Masuda T, Canver MC, Seiler M, Semba Y, Shboul M, et al. Genome-
wide CRISPR-Cas9 screen identifies leukemia-specific dependence on a pre-
mRNA metabolic pathway regulated by DCPS. Cancer Cell. 2018;33:386–400.e5. Open Access This article is licensed under a Creative Commons
Attribution 4.0 International License, which permits use, sharing,
adaptation, distribution and reproduction in any medium or format, as long as you give
appropriate credit to the original author(s) and the source, provide a link to the Creative
Commons license, and indicate if changes were made. The images or other third party
material in this article are included in the article’s Creative Commons license, unless
indicated otherwise in a credit line to the material. If material is not included in the
article’s Creative Commons license and your intended use is not permitted by statutory
regulation or exceeds the permitted use, you will need to obtain permission directly
from
the
copyright
holder. To
view
a
copy
of
this
license,
visit
http://
creativecommons.org/licenses/by/4.0/. 55. Li F, Huang Q, Luster TA, Hu H, Zhang H, Ng WL, et al. In vivo epigenetic CRISPR
screen identifies Asf1a as an immunotherapeutic target in Kras-mutant lung
adenocarcinoma. Cancer Discov. 2020;10:270–87. 56. Scheidmann MC, Castro-Giner F, Strittmatter K, Krol I, Paasinen-Sohns A, Scherrer
R, et al. An in vivo CRISPR screen identifies stepwise genetic dependencies of
metastatic progression. Cancer Res. 2022;82:681–94. 57. Heitink L, Whittle JR, Vaillant F, Capaldo BD, Dekkers JF, Dawson CA, et al. In vivo
genome-editing screen identifies tumor suppressor genes that cooperate with
Trp53 loss during mammary tumorigenesis. Mol Oncol. 2022;16:1119–31. 58. Gautron A, Bachelot L, Aubry M, Leclerc D, Quéméner AM, Corre S, et al. CRISPR
screens identify tumor-promoting genes conferring melanoma cell plasticity and
resistance. EMBO Mol Med. 2021;13:e13466. 59. Liu R, Holik AZ, Su S, Jansz N, Chen K, Leong HS, et al. Why weight? Modelling
sample and observational level variability improves power in RNA-seq analyses. Nucleic Acids Res. 2015;43:e97. Reprints and permission information is available at http://www.nature.com/
reprints © The Author(s) 2023 © The Author(s) 2023 Cancer Gene Therapy (2023) 30:1610 – 1623
|
https://openalex.org/W4320342313
|
https://arpi.unipi.it/bitstream/11568/1027628/2/PhysRevD.100.032007.pdf
|
English
| null |
Search for the electroweak diboson production in association with a high-mass dijet system in semileptonic final states in <math xmlns="http://www.w3.org/1998/Math/MathML">
<mi>p</mi>
<mi>p</mi>
</math> collisions at <math xmlns="http://www.w3.org/1998/Math/MathML">
<msqrt>
<mi>s</mi>
</msqrt>
<mo>=</mo>
<mn>13</mn>
</math> TeV with the ATLAS detector
|
OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information)
| 2,019
|
cc-by
| 38,790
|
PHYSICAL REVIEW D 100, 032007 (2019) PHYSICAL REVIEW D 100, 032007 (2019) (Received 21 May 2019; published 22 August 2019) This paper reports on a search for electroweak diboson (WW=WZ=ZZ) production in association with a
high-mass dijet system, using data from proton-proton collisions at a center-of-mass energy of
ffiffiffis
p ¼ 13 TeV. The data, corresponding to an integrated luminosity of 35.5 fb−1, were recorded with
the ATLAS detector in 2015 and 2016 at the Large Hadron Collider. The search is performed in final states
in which one boson decays leptonically, and the other boson decays hadronically. The hadronically
decaying W=Z boson is reconstructed as either two small-radius jets or one large-radius jet using jet
substructure techniques. The electroweak production of WW=WZ=ZZ in association with two jets is
measured with an observed (expected) significance of 2.7 (2.5) standard deviations, and the fiducial cross
section is measured to be 45.1 8.6ðstat:Þþ15.9
−14.6ðsyst:Þ fb. Published by the American Physical Society under the terms of
the Creative Commons Attribution 4.0 International license.
Further distribution of this work must maintain attribution to
the author(s) and the published article’s title, journal citation,
and DOI. Funded by SCOAP3. Search for electroweak diboson production in association
with a high-mass dijet system in semileptonic final states
in pp collisions at
ffiffis
p = 13 TeV with the ATLAS detector G. Aad et al.*
(ATLAS Collaboration) I. INTRODUCTION VVjj (V ¼ W, Z, γ), with a large separation in rapidity of
jets and a large dijet invariant mass. Multiple processes can
produce the same final state of two bosons and two jets. The production of VVjj at tree level has an EW contri-
bution involving only electroweak-interaction vertices, and
a strong contribution (QCD induced) involving two strong-
interaction vertices. The EW production is further divided
into two components. The first component is EW VBS
production with actual scattering of the two electroweak
bosons. The scattering occurs via quartic gauge vertices,
or triple gauge vertices involving the s- or t-channel
exchange of a Higgs boson or a W=Z boson. The second
component is EW non-VBS production that has electro-
weak vertices only, but where the two bosons do not scatter. The EW non-VBS component cannot be separated from the
EW VBS component in a gauge invariant way [13] and
contributes significantly to the total cross section. It is
therefore included in the signal generation. Representative
Feynman diagrams at tree level are shown in Fig. 1. Both
the ATLAS and CMS Collaborations have searched for
experimental evidence of VBS. So far, electroweak VVjj
production is only observed in the same-sign WWjj
channel [14] and WZjj channel [15] in the fully leptonic
final states using data collected at a center-of-mass
energy of
ffiffiffis
p ¼ 13 TeV. Evidence of electroweak VVjj
production is also obtained in the WWjj [16–18]
and Zγjj [19] channels using pp collisions at
ffiffiffis
p ¼
8 TeV. Limits on fiducial cross sections of electroweak
VVjj production are reported for the WZjj [20,21], ZZjj
[22], Zγjj [23] and Wγjj [24] channels. Constraints on
anomalous quartic
gauge
couplings
are
reported
in
Refs. [16–19,21,23–27]. VVjj (V ¼ W, Z, γ), with a large separation in rapidity of
jets and a large dijet invariant mass. Multiple processes can
produce the same final state of two bosons and two jets. The production of VVjj at tree level has an EW contri-
bution involving only electroweak-interaction vertices, and
a strong contribution (QCD induced) involving two strong-
interaction vertices. The EW production is further divided
into two components. The first component is EW VBS
production with actual scattering of the two electroweak
bosons. The scattering occurs via quartic gauge vertices,
or triple gauge vertices involving the s- or t-channel
exchange of a Higgs boson or a W=Z boson. *Full author list given at the end of the article. DOI: 10.1103/PhysRevD.100.032007 2The ATLAS experiment uses a right-handed coordinate
system with its origin at the nominal interaction point (IP) in
the center of the detector and the z axis along the axis of the beam
pipe. The x axis points from the IP to the center of the LHC ring,
and the y axis points upwards. Cylindrical coordinates ðr; ϕÞ are
used in the transverse plane, ϕ being the azimuthal angle around
the z axis. The pseudorapidity is defined in terms of the polar
angle θ as η ¼ −ln tanðθ=2Þ. Angular distance is measured in
units of ΔR ≡
ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
ðΔηÞ2 þ ðΔϕÞ2
p
. I. INTRODUCTION Representative Feynman diagrams for (a) EW VVjj production via VBS, (b) EW VVjj production via non-VBS contribution,
and (c) QCD VVjj production. (c) (b) (a) (c) (b) (a) FIG. 1. Representative Feynman diagrams for (a) EW VVjj production via VBS, (b) EW VVjj production via non-VBS contribution,
and (c) QCD VVjj production. final states, each using resolved or merged V →qq
reconstruction techniques. Reference [26] reports a study similar to the one in this
paper, albeit focused on EW production of VVjj in the
WV →lνqq channel only and performed at
ffiffiffis
p ¼ 8 TeV. This paper presents a study of the EW production of VVjj
(V ¼ W, Z) with the vector-boson pair decaying semi-
leptonically. A larger data sample is used and additional
diboson signal processes with similar final states are
included. In order to extract the signal and to measure the cross
section for the EW production of VVjj in a fiducial
volume, multivariate discriminants, which combine observ-
ables sensitive to the kinematics of the VBS process, are
used to separate EW-induced VVjj production from QCD-
induced VVjj production. This analysis measures the cross section of EW VVjj
production in a region of kinematic phase space close to the
acceptance of the detector. Fiducial cross sections are
measured in the 0-, 1- and 2-lepton channels, where lepton
refers to e and μ. Final states with V decaying into one or
more
τ-leptons
(both
leptonically
and
hadronically
decaying τ-leptons) are included as signal, but the con-
tribution of V from top quark decay is not considered as
signal. Three VV semileptonic decay channels are explored: a Z
boson decaying into a pair of neutrinos, Z →νν1; a W
boson decaying into a charged lepton (an electron or muon,
denoted by l) and a neutrino, W →lν; and a Z boson
decaying into a pair of light charged leptons, Z →ll. In all
cases, the other vector boson V is required to decay into a
pair of quarks, V →qq, leading to ZV →ννqq, WV →
lνqq and ZV →llqq final states. These processes overlap
in the fiducial region of the measurement because of the
geometrical acceptance of the detector for leptons and jets. I. INTRODUCTION The second
component is EW non-VBS production that has electro-
weak vertices only, but where the two bosons do not scatter. The EW non-VBS component cannot be separated from the
EW VBS component in a gauge invariant way [13] and
contributes significantly to the total cross section. It is
therefore included in the signal generation. Representative
Feynman diagrams at tree level are shown in Fig. 1. Both
the ATLAS and CMS Collaborations have searched for
experimental evidence of VBS. So far, electroweak VVjj
production is only observed in the same-sign WWjj
channel [14] and WZjj channel [15] in the fully leptonic
final states using data collected at a center-of-mass
energy of
ffiffiffis
p ¼ 13 TeV. Evidence of electroweak VVjj
production is also obtained in the WWjj [16–18]
and Zγjj [19] channels using pp collisions at
ffiffiffis
p ¼
8 TeV. Limits on fiducial cross sections of electroweak
VVjj production are reported for the WZjj [20,21], ZZjj
[22], Zγjj [23] and Wγjj [24] channels. Constraints on
anomalous quartic
gauge
couplings
are
reported
in
Refs. [16–19,21,23–27]. Vector-boson scattering (VBS) is a key process for
probing the non-Abelian gauge structure of the electroweak
(EW) sector of the Standard Model (SM), since it involves
both the self-couplings of the vector bosons and their
coupling with the Higgs boson. In the absence of the SM
Higgs boson, the amplitudes for VBS would increase as a
function of partonic center-of-mass energy and ultimately
violate unitarity [1,2]. The discovery of a Higgs boson in
2012 at the LHC [3,4], with measured properties [5–8]
consistent with those of the SM Higgs boson, represents a
major milestone in the understanding of electroweak
symmetry breaking. The study of the VBS process provides
an important check of the SM by testing whether the Higgs
mechanism is the sole source of electroweak symmetry
breaking. Theories of new phenomena beyond the SM
that alter the quartic gauge couplings [9,10], or include
the presence of additional resonances [11,12], predict
enhancements of VBS at high transverse momentum of
the vector bosons and at high invariant mass of the diboson
system. The experimental signature of VBS is characterized by
the presence of a pair of vector bosons and two forward jets, © 2019 CERN, for the ATLAS Collaboration 032007-1 2470-0010=2019=100(3)=032007(36) PHYS. REV. D 100, 032007 (2019) G. AAD et al. (a)
(b)
(c)
FIG. 1. 1To simplify the notation, antiparticles are not explicitly
labeled in this paper. I. INTRODUCTION The decay channels are selected as 0-, 1- and 2-lepton final
states, where the 1-lepton (2-lepton) final state receives
only contribution from WV→lνqq (ZV→llqq) proc-
esses, and the 0-lepton final state receives about equal
contributions
from
WV →lνqq
and
ZV →ννqq
processes. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … constant. Both the VBS amplitudes and non-VBS ampli-
tudes of the VVjj process with one boson decaying
hadronically and the other leptonically were included,
using factorized on-shell decays for the gauge bosons. The NNPDF30LO [31] PDF set was used. The parton
showers and hadronization were modeled with PYTHIA
8.186 [32] using the A14 set of tuned parameters (tune) for
the underlying event [33]. The end cap and forward regions are instrumented with
LAr calorimeters for both EM and hadronic energy
measurements up to jηj ¼ 4.9. A muon spectrometer
(MS) system incorporating large superconducting toroidal
air-core magnets surrounds the calorimeters. Three layers
of precision wire chambers provide muon tracking in the
range jηj < 2.7, while dedicated fast chambers are used
for triggering in the region jηj < 2.4. The trigger system is
composed of two stages [29]. The first stage, implemented
with custom hardware, uses information from calorimeters
and muon chambers to reduce the event rate to a maximum
of 100 kHz. The second stage, called the high-level
trigger, reduces the data acquisition rate to about 1 kHz
on average. The high-level trigger is software-based and
runs reconstruction algorithms similar to those used in the
offline reconstruction. The main background sources are Z and W bosons
produced in association with jets (Z þ jets and W þ jets),
as well as significant contributions from top quark pro-
duction (both t¯t pair and single-top) and QCD-induced
vector-boson pair production. The Z þ jets and W þ jets
events were simulated using the SHERPA 2.2.1 [34] event
generator. Matrix elements were calculated for up to two
partons at NLO and up to four partons at LO using the
COMIX [35] and OPENLOOPS [36] programs. QCD-induced
diboson processes with one of the bosons decaying
hadronically and the other leptonically were simulated
using SHERPA 2.2.1. They were simulated for up to one
additional parton at NLO and up to three additional partons
at LO using the COMIX and OPENLOOPS programs. There is
no overlap between the QCD-induced diboson samples and
the EW VVjj signal samples, as the former include
diagrams of Oðα4
EWα2
SÞ. For Z þ jets, W þ jets and diboson
simulation, the matrix-element calculations were merged
with the SHERPA parton shower using the ME þ PS@NLO
prescription [37]. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … The NNPDF30NNLO [38] PDF set was
used in conjunction with a dedicated parton-shower tuning
developed by the SHERPA authors. For the Z þ jets and W þ
jets samples, boson decays into all lepton flavors (e, μ, τ) are
included. For the generation of top quark pairs, the POWHEG-
BOX V2 [39–41] event generator with the CT10 [42] PDF set
in the matrix-element calculations was used. Electroweak t-
channel, s-channel and Wt-channel single-top-quark events
were generated using the POWHEG-BOX V1 event generator
[43–45]. This event generator uses the four-flavor scheme
for the NLO matrix-element calculations together with the
fixed four-flavor PDF set CT10f4 [42]. For all top quark
processes, top quark spin correlations are preserved (for the
t-channel, top quark decay is simulated using MADSPIN
[46]). The parton showers, fragmentation, and underlying
event were simulated using PYTHIA 6.428 [47] with the
CTEQ6L1 [48] PDF set and the corresponding Perugia 2012
tune (P2012) [49]. The top quark mass was set to 172.5 GeV. The EVTGEN V1.2.0 program [50] was used to simulate the
decay of bottom and charm hadrons for the POWHEG-BOX
samples. A. Data The data were collected with the ATLAS detector in 2015
and 2016 from pp collisions at a center-of-mass energy of
ffiffiffis
p ¼ 13 TeV, corresponding to a total integrated luminos-
ity of 35.5 fb−1. The recorded 2-lepton channel and 1-lepton channel
events were selected with a mixture of either multiple
single-electron or single-muon triggers with varying trans-
verse energy ET (electron) and transverse momentum pT
(muon) thresholds, and quality and isolation requirements,
that depended on the LHC running conditions. The lowest
ET or pT requirement without trigger prescaling was
26 GeV for both the electrons and muons. Events for
the 0-lepton channel were recorded with nonprescaled
missing transverse momentum (Emiss
T
) triggers where the
Emiss
T
threshold depended on the LHC running conditions. The lowest threshold used is 110 GeV. The Emiss
T
triggers
used are fully efficient for events passing the selection
described below. The Emiss
T
triggers are also used in the
1-lepton channel to compensate for single-muon trigger
inefficiency due to the difference in acceptance between the
muon tracking and triggering. Events in this analysis have all detector systems operat-
ing normally. Collision vertices are formed from tracks with
pT > 400 MeV, and the one with the highest P p2
T of its
associated tracks is selected as the primary vertex. II. ATLAS DETECTOR The ATLAS experiment is described in Ref. [28]. ATLAS is a multipurpose detector with a forward-back-
ward symmetric cylindrical geometry and a solid-angle2
coverage of nearly 4π. The inner tracking detector (ID),
covering the region jηj < 2.5, consists of a silicon pixel
detector, a silicon microstrip detector and a straw-tube
transition-radiation tracker. The inner detector is sur-
rounded by a thin superconducting solenoid providing
a 2 T magnetic field, and by a finely segmented lead/
liquid-argon (LAr) electromagnetic calorimeter covering
the region jηj < 3.2. A steel/scintillator-tile hadronic calo-
rimeter provides coverage in the central region jηj < 1.7. p
Two different reconstruction techniques for the V →qq
decay are considered: resolved and merged. The resolved
reconstruction attempts to identify two separate small-
radius jets (small-R jet denoted by j) of hadrons from
the V →qq decay, while the merged reconstruction uses jet
substructure techniques to identify the V →qq decay
reconstructed as a large-radius jet (large-R jet denoted
by J). The latter applies when the momentum transfer in
VVjj production is high, and as a consequence the qq pair
from the V boson decay is collimated. In this case, hadrons
from the two quarks overlap in the detector and are more
efficiently reconstructed as a single large-R jet. In total, six
final states are included in this study: 0-, 1- and 2-lepton 032007-2 PHYS. REV. D 100, 032007 (2019) III. DATA AND MONTE CARLO SIMULATION A. Data B. Signal and background simulation Monte Carlo (MC) simulation is used to model signal
and background processes. The simulated samples are used
to optimize the event selection, to develop the multivariate
discriminant, and to estimate the irreducible background
yields. All simulated processes are normalized using the cur-
rently available state-of-the-art theoretical predictions for
their cross sections. Cross sections are calculated with up to
next-to-next-to-leading-order (NNLO) QCD corrections
for Z þ jets and W þ jets production [51]. Cross sections
for diboson production are calculated at NLO including LO
contributions with two additional partons [34,52]. The t¯t The EW VVjj signal samples were generated using
MADGRAPH5_AMC@NLO 2.4.3 [30] with amplitudes of
Oðα6
EWα0
SÞ, where αEW (αS) is the EW (strong) coupling 032007-3 PHYS. REV. D 100, 032007 (2019) G. AAD et al. production cross section is calculated at NNLO in QCD,
including resummation of next-to-next-to-leading logarith-
mic (NNLL) soft-gluon terms [53,54]. The single-top
production cross sections are calculated to NLO in QCD
[55], including the soft-gluon resummation at NNLL [56]
for the Wt process. production cross section is calculated at NNLO in QCD,
including resummation of next-to-next-to-leading logarith-
mic (NNLL) soft-gluon terms [53,54]. The single-top
production cross sections are calculated to NLO in QCD
[55], including the soft-gluon resummation at NNLL [56]
for the Wt process. [64,65] but with different values of the radius parameter
R. Small-R jets and large-R jets are reconstructed inde-
pendently from the same energy depositions for a given
event. The treatment of the resulting overlap is discussed
further below. Small-R jets are reconstructed with a radius parameter
of R ¼ 0.4. Energy- and η-dependent correction factors
derived from MC simulations are applied to correct
jets back to the particle level [66]. Pileup effects are
corrected using a jet area method [67,68]. Jets are required
to have pT > 20 GeV for jηj < 2.5 and pT > 30 GeV for
2.5 < jηj < 4.5. A jet vertex tagger [67] is applied to jets
with pT < 60 GeV and jηj < 2.4 in order to select only jets
from the hard interaction which are associated with the
primary vertex, and to suppress jets from pileup inter-
actions. This tagger uses information about tracks asso-
ciated with the primary vertex and pileup vertices. MC events were processed with a detailed detector
simulation [57] based on GEANT4 [58]. IV. OBJECT RECONSTRUCTION Small-R jets containing b-hadrons are identified using a
multivariate algorithm (b-tagging) [69] which uses infor-
mation such as track impact-parameter significance and the
position of explicitly reconstructed secondary decay ver-
tices. The chosen b-tagging algorithm has an efficiency of
70% for b-quark jets in simulated t¯t events, with a light-
flavor jet rejection factor of about 380 and a c-jet rejection
factor of about 12 [70]. Electrons are identified as isolated energy clusters in the
electromagnetic calorimeter matched to ID tracks, and are
required to have transverse energy ET > 7 GeV and
pseudorapidity jηj < 2.47. A likelihood-based requirement
[61] is imposed to reduce the background from nonprompt
electrons or hadrons misidentified as electrons. Electrons
are classified as either “loose,” “medium” or “tight”
according to the likelihood-based identification criteria
described in Ref. [61]. Large-R jets are reconstructed with the radius parameter
increased to R ¼ 1.0. In order to mitigate the effects of
pileup and soft radiation, the large-R jets are trimmed [71]. Trimming takes the original constituents of the jet and
reclusters them using the kt algorithm [72] with a smaller
radius parameter, Rsubjet, to produce a collection of subjets. These subjets are discarded if they carry less than a specific
fraction (fcut) of the original jet pT. The trimming param-
eters were optimized for W=Z boson tagging and are
Rsubjet ¼ 0.2 and fcut ¼ 5%. The large-R jet four-momenta
are recomputed from the remaining subjets, and the jet
energies are calibrated to particle level using correction
factors derived from MC simulations [73]. The mass of a
large-R jet (mJ) is computed using a combination of
calorimeter and tracking information [74]. Large-R jets
are required to have pT > 200 GeV and jηj < 2.0. Muons are reconstructed by a combined fit to the ID and
MS tracks, and are required to have pT > 7 GeV and
jηj < 2.5. Muons must pass identification requirements,
based on the number of hits in the ID and MS subsystems,
and the significance of the difference jq=pMS −q=pIDj
[62], where q is the charge and pMSðpIDÞ is the momentum
of the muon measured in the MS (ID). Similarly to
electrons, muons are classified as either loose, medium
or tight, following the criteria in Ref. [62]. B. Signal and background simulation Additional inelastic
simulated pp collisions generated with PYTHIA 8.186 using
the A2 set of tuned parameters [59] and the MSTW2008LO
[60] PDF set were overlaid in order to model both the in-
and out-of-time effects from additional pp collisions in the
same and neighboring bunch crossings (pileup). MC
samples are reweighted to match the pileup conditions in
the data. All simulated events are processed using the same
reconstruction algorithms as the data. A. Event selection Signal events in the 0-lepton channel are typical of a
hadronically decaying V boson recoiling against a large
amount of missing transverse momentum stemming from
either a Z →νν decay or a W →lν decay, where the
lepton is outside the acceptance of the detector. An
initial selection is made by requiring Emiss
T
> 200 GeV,
and rejecting events with electrons or muons passing
the loose quality requirements. The multijet background
originates primarily from the presence of mismeasured
jets
and
noncollision
phenomena. It
is
suppressed
using a requirement on the value of the track-based
missing transverse momentum, pmiss
T
> 50 GeV. Three
further angular selection criteria are: the azimuthal
separation
between
the
⃗Emiss
T
and
⃗pmiss
T
directions
satisfies Δϕð⃗Emiss
T
; ⃗pmiss
T
Þ < π=2; the azimuthal separation
between the directions of ⃗Emiss
T
and the nearest small-R
jet satisfies min½Δϕð⃗Emiss
T
; small-R jetÞ > π=6; and the
azimuthal separation between the directions of ⃗Emiss
T
and
the reconstructed hadronically decaying candidate Vhad
satisfies Δϕð⃗Emiss
T
; VhadÞ > π=9. The multijet background
is found to be negligible after these selections. p
y
The missing transverse momentum vector, ⃗Emiss
T
, is
calculated as the negative vectorial sum of the transverse
momenta of calibrated electrons, muons, and small-R jets
where the calibration already includes corrections for
pileup. Large-R jets and track jets are not included in
the ⃗Emiss
T
calculation in order to avoid double-counting of
energy between the small-R jets and large-R jets. Energy
depositions due to the underlying event and other types of
soft radiation are taken into account by constructing a “soft
term” from ID tracks that are associated with the primary
vertex but not used in any reconstructed object [79]. The
track-based missing transverse momentum vector, ⃗pmiss
T
, is
the negative vectorial sum of the transverse momenta of all
good-quality inner-detector tracks that are associated with
the primary vertex. The 1-lepton channel is typical of a leptonically
decaying W boson. The W →lν candidates are selected
by requiring one isolated lepton (electron or muon)
satisfying the tight criteria with pT > 27 GeV. Events
are required to have Emiss
T
> 80 GeV, and must not
have any additional loose leptons. A. Event selection In order to reconstruct
the invariant mass of the WV system, needed later to
construct the multivariate discriminant, the neutrino
momentum four-vector is reconstructed by imposing
a W boson mass constraint on the lepton–neutrino system. The neutrino transverse momentum components are set
equal to the missing transverse momentum of the
event and the unknown z-component of the momentum
(pz) is obtained from the resulting quadratic equation. The pz is chosen as either the smaller, in absolute value,
of the two real solutions or, if the solution is complex, its
real part. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … between the muon and the jet are small; otherwise the
muon is removed if the separation satisfies ΔR < 0.4. In
order to prevent double-counting of energy from an
electron inside a large-R jet, the large-R jet is removed
if an electron and a large-R jet are separated by ΔR < 1.0. No overlap removal is applied between large-R jets or track
jets and small-R jets. (V →J) in a merged selection, and those jets are referred
to as Vhad jets. Event selection criteria are chosen to
guarantee the statistical independence of the channels and
to maximize the sensitivity of the analysis. This selection
results in nine nonoverlapping distinct signal regions
(SR): one for each of the three lepton channels and three
types of Vhad selections (resolved, and low- and high-
purity merged). Boson tagging is applied to large-R jets in order to select
those consistent with V →qq decays. A pT-dependent
requirement is applied to the jet substructure variable
Dðβ¼1Þ
2
, which is defined as a ratio of two-point to
three-point energy correlation functions [76,77] that are
based on the energies and pairwise angular separations of
the particles within a jet. This variable is optimized to
distinguish between jets originating from a single parton
and those coming from the two-body decay of a heavy
particle. A detailed description of the method and its
optimization can be found in Ref. [78]. Large-R jets from
V →qq decays are required to have a jet mass mJ in a pT-
dependent window centered around the expected value of
the boson mass. The configuration of the boson tagging
algorithm is called a working point, which is designed to
provide constant efficiency independent of the large-R jet
pT for the signals studied. Two working points are used,
one with 50% efficiency and the other one with 80%
efficiency, with corresponding misidentification rates for
jets from multijet production of
∼2% and ∼10%,
respectively. ⃗
i The event selection for all channels and background
estimations is summarized in Table I. Further details are
given below. IV. OBJECT RECONSTRUCTION All electrons and muons are required to be isolated by
using selections based on the sum of the pT of tracks
(excluding the track associated with the lepton) in a cone of
pT-dependent size around their directions. The isolation
selection criteria are designed to maintain a constant
efficiency of 99% in the pT-η plane for reconstructed
leptons from Z →ll decays. Furthermore, leptons are
required to have associated tracks satisfying jd0=σd0j <
5ð3Þ and jz0 × sin θj < 0.5 mm for electrons (muons),
where d0 is the transverse impact parameter relative to
the beam line, σd0 is its uncertainty, and z0 is the distance
between the longitudinal position of the track along the
beam line at the point where d0 is measured and the
longitudinal position of the primary vertex. j j
Track jets have a radius parameter of R ¼ 0.2 [75]. Inner-detector tracks originating from the primary vertex,
with pT>0.5GeV and selected by impact parameter
requirements, are used in the track jet reconstruction. Track jets are required to satisfy pT>20GeV and
jηj<2.5. The number of track jets is an input to the
multivariate discriminant described later. An overlap-removal procedure is applied to the selected
leptons and jets in order to prevent double-counting. The jet
is removed if an electron and a small-R jet are separated by
ΔR < 0.2; the electron is removed if the separation satisfies
0.2 < ΔR < 0.4. The jet is removed if a muon and a
small-R jet are separated by ΔR < 0.2 and if the jet has less
than three tracks or the energy and momentum differences Three types of jets are employed in the analysis. Two of
them are reconstructed from three-dimensional topological
clusters of energy deposits in the calorimeter [63] (small-R
jets and large-R jets), and the third type from inner-detector
tracks (track jets). All three use the anti-kt algorithm 032007-4 PHYS. REV. D 100, 032007 (2019) SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … V. EVENT SELECTION AND BACKGROIUND
ESTIMATION j j
V boson tagging, minðjmJ −mWj; jmJ −mZjÞ
64 < mjj < 106 GeV, jj pair with minðjmjj −mWj; jmjj −mZjÞ, leading jet with pT > 40 GeV j ∉Vhad, not b-tagged, ΔRðJ; jÞ > 1.4
ηtag;j1 · ηtag;j2 < 0, mtag
jj > 400 GeV, pT > 30 GeV lepton must satisfy pT > 28ð20Þ GeV. Opposite charges
are required for the muon pairs but not for the electron
pairs, since electrons are more susceptible to charge
misidentification due to the conversion of photons from
bremsstrahlung, especially at high pT. The dilepton invari-
ant mass is required to be consistent with that of the Z
boson: 83 < mee < 99 GeV in the case of electrons and
ð−0.0117 × pμμ
T þ 85.63 GeVÞ < mμμ < ð0.0185 × pμμ
T þ
94 GeVÞ in the case of muons. The pT-dependent require-
ment on mμμ recovers the selection efficiency at high pμμ
T ,
which would otherwise fall due to the degraded dimuon
invariant mass resolution [80]. point requirement. The former is called the high-purity
(HP) signal region, and the latter the low-purity (LP)
signal region. Given the different but overlappping W and
Z boson tagging requirements, large-R jets are required
to satisfy either W or Z boson tagging. If multiple Vhad
candidates are selected, the one minimizing minðjmJ −
mWj; jmJ −mZjÞ is selected. The resolved selection events are required to have two
small-R signal jets with a dijet invariant mass lying in
the mW=Z window: 64 < mjj < 106 GeV. If multiple
Vhad
candidates
are
selected,
the
one
minimizing
minðjmjj −mWj; jmjj −mZjÞ is used. At least one of
the jets forming the selected Vhad candidate must have
pT > 40 GeV,
in
order
to
improve
the
separation
between the signal and the background; otherwise the
event is not selected. The merged selection is applied as the first step in
identifying a Vhad candidate. If an event is not selected, then
the resolved selection is used. The order is motivated by a
smaller background expectation in the merged analysis. Selecting the jets that form a Vhad candidate first and then
selecting the tagging-jets from the pool of remaining jets
results in an analysis with a higher sensitivity compared
with doing the selection in the reverse order. The Vhad
candidates are selected in three different nonoverlapping
channels. V. EVENT SELECTION AND BACKGROIUND
ESTIMATION Events are categorized into the 0-, 1- and 2-lepton
channels depending on the number of selected electrons
and muons. In addition to a leptonically decaying candi-
date Vlep, events in all three channels are required to
contain a hadronically decaying candidate Vhad, and two
additional small-R jets (referred to as tagging-jets). The
Vhad candidate is reconstructed as either two small-R jets
(V →jj) in a resolved selection, or one large-R jet In the 2-lepton channel, the Z →ll candidates are
identified by requiring two isolated same-flavor leptons
satisfying the loose criteria. The leading (subleading) 032007-5 PHYS. REV. D 100, 032007 (2019) G. AAD et al. TABLE I. Summary of the event selection in the 0-, 1- and 2-lepton channels. Selection
0-lepton
1-lepton
2-lepton
Trigger
Emiss
T
triggers
Single-electron triggers
Single-lepton triggers
single-muon or Emiss
T
triggers
Leptons
0 loose leptons
with pT > 7 GeV
1 tight lepton with pT > 27 GeV
2 loose leptons with pT > 20 GeV
0 loose leptons with pT > 7 GeV
≥1 lepton with pT > 28 GeV
Emiss
T
>200 GeV
>80 GeV
mll
83 < mee < 99 GeV
ð−0.0117 × pμμ
T þ 85.63 GeVÞ
< mμμ < ð0.0185 × pμμ
T þ 94 GeVÞ
Small-R jets
pT > 20 GeV if jηj < 2.5, and pT > 30 GeV if 2.5 < jηj < 4.5
Large-R jets
pT > 200 GeV, jηj < 2
Vhad →J
V boson tagging, minðjmJ −mWj; jmJ −mZjÞ
Vhad →jj
64 < mjj < 106 GeV, jj pair with minðjmjj −mWj; jmjj −mZjÞ, leading jet with pT > 40 GeV
Tagging-jets
j ∉Vhad, not b-tagged, ΔRðJ; jÞ > 1.4
ηtag;j1 · ηtag;j2 < 0, mtag
jj > 400 GeV, pT > 30 GeV
Num. of b-jets
0
Multijet removal
pmiss
T
> 50 GeV
Δϕð⃗Emiss
T
; ⃗pmiss
T
Þ < π=2
min½Δϕð⃗Emiss
T
; small-R jetÞ > π=6
Δϕð⃗Emiss
T
; VhadÞ > π=9 of the event selection in the 0-, 1- and 2-lepton channels. B. Data control regions and background estimation The dominant backgrounds for the 1-lepton channel are
W þ jets and t¯t production; for the 2-lepton channel it is
Z þ jets production; while in the 0-lepton channel, they all
contribute significantly. Smaller background contributions
for the 1-lepton channel arise from multijet background. Single-top and QCD-induced diboson production is a small
background for all three lepton channels. The background
contributions are estimated using a combination of MC and
data-driven techniques. The shapes of kinematic variable
distributions are taken from MC simulations in all cases
except for the multijet background in the 1-lepton channel. p
The mtag
jj spectra of simulated W þ jets (Z þ jets) events
are not well modeled by the MC simulation in the WCRs
(ZCRs) for the three Vhad selections in the 1-lepton (2-
lepton) channel. A data-driven procedure is applied to the
simulated W þ jets and Z þ jets events to correct for this
shape mismodeling. Reweighting factors are derived from
WCRs and ZCRs as a function of mtag
jj , and applied to all
SRs and CRs (for 0-, 1-, and 2-lepton regions) in the MC
simulation of W þ jets and Z þ jets events, respectively. The non-W þ jetsðZ þ jetsÞ contributions are subtracted
from the spectra in data. Then the reweighting factors as a
function of mtag
jj are determined by performing a linear fit to
the ratios of data to simulation in the control regions. The reweighting is done separately for the merged and
resolved analyses. For W þ jets, the reweighting factor
ranges from 1.016 (1.024) at mtag
jj ¼ 400 GeV to 0.47 (0.53)
at mtag
jj ¼ 3000 GeV in the resolved (merged) analysis. For
Z þ jets, the reweighting factor ranges from 1.071 (1.062)
at mtag
jj ¼ 400 GeV to 0.42 (0.36) at mtag
jj ¼ 3000 GeV in
the resolved (merged) analysis. A Z þ jets control region (ZCR) is defined for each of
the three SRs in the 2-lepton channel by reversing the mJ or
mjj requirement. Events in each of the CRs are selected in
exactly the same way as those in their corresponding
SRs except for the requirement on mJ or mjj. For the
merged selection, the leading large-R jet mass is required
to be outside the large-R jet mass window of the 80%
working point of the W=Z boson tagging. B. Data control regions and background estimation For the resolved
selection, a requirement of 50 < mjj < 64 GeV or mjj >
106 GeV is applied. These CRs are dominated by the
Z þ jets contribution, with a purity higher than 95% in
all regions. They are therefore used to constrain its
contribution in signal regions through simultaneous fits
as discussed in Sec. X. g
y
Additional reweighting factors are needed for the
MC simulation of W þ jets and Z þ jets events in the
0-lepton channel because the phase space is so different
between the 0-lepton selection and the 1- and 2-lepton
selections that the reweightings described above are not
applicable. These additional reweightings are derived
from MC simulation as the ratio of the numbers of W þ
jets (Z þ jets) events in the 1-lepton (2-lepton) and
0-lepton channels, and are applied to the MC simulation
of W þ jets (Z þ jets) events in the 0-lepton channel. Good
agreement
between
the
prediction
from
MC
simulation and the data in the VjjCR is achieved only
after the two reweightings have been applied. Unless
stated otherwise, the final reweighted W þ jets and Z þ
jets simulated events are used everywhere in the analysis. Three W þ jets control regions (WCRs) are formed from
events satisfying the 1-lepton signal region selection except
for the invariant mass requirement of the Vhad candidate,
similar to the ZCRs. Approximately 86% and 77% of the
selected events are from W þ jets production in the merged
and resolved categories of the 1-lepton channel, respec-
tively. The remaining events are primarily from t¯t
production. The three t¯t control regions (TopCRs) consist of events
satisfying the signal region selection of the 1-lepton
channel except for the b-jet requirement, which is inverted. These CRs are dominated by t¯t production, with a purity of
79% and 59% for merged and resolved categories respec-
tively, and the remainder are from single-top, V þ jets or
diboson production, for both the merged and the resolved
event topologies. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … misidentified as leptons or real but nonprompt leptons
from decays of heavy-flavor hadrons. This contribution is
negligible in all regions, except for the resolved 1-lepton
SR. The fake-factor background method of Ref. [81] is
used to estimate the multijet background contribution in the
resolved topology of the 1-lepton channel. The estimated
multijet contribution is about 10% of the total background
in the resolved 1-lepton SR. Finally, 1-lepton channel events are rejected if any of the
small-R jets in the event is identified as a b-jet prior to
the Vhad candidate and tagging-jets selection. This reduces
the contributions from top quark production. V. EVENT SELECTION AND BACKGROIUND
ESTIMATION After selecting the Vhad candidate, tagging-jets are
selected from the remaining small-R jets that fail the b-
tagging described in Sec. IV. For the merged selection, all
small-R jets with ΔRðJ; jÞ < 1.4 are excluded before the
tagging-jets selection. Tagging-jets are required to be in
opposite hemispheres, ηtag;j1 · ηtag;j2 < 0, and the invariant
massofthetwotagging-jets mustsatisfymtag
jj > 400 GeV.If
there is more than one pair of jets satisfying these require-
ments, the one with the highest mtag
jj value is chosen. In order
to suppress the contribution from pileup interactions, both
tagging-jets from the selected pair must have pT > 30 GeV;
otherwise the event is rejected. Merged selection events are required to have at least
one large-R jet. Next the boson tagging discussed in
Sec. IV is applied to select the V →qq decays. Two SRs
are defined, one for events passing the 50% working
point of the boson tagging requirement and the other for
events failing the 50%, but passing the 80% working 032007-6 PHYS. REV. D 100, 032007 (2019) VI. MULTIVARIATE ANALYSIS Variable
0-lepton
1-lepton
2-lepton
mtag
jj
✓
✓
Δηtag
jj
✓
ptag;j1
T
✓
✓
ptag;j2
T
✓
✓
✓
Δηjj
✓
✓
✓
pj1
T
✓
pj2
T
✓
✓
✓
wj1
✓
✓
✓
wj2
✓
✓
✓
nj1
tracks
✓
✓
nj2
tracks
✓
✓
wtag;j1
✓
✓
✓
wtag;j2
✓
✓
✓
ntag;j1
tracks
✓
✓
ntag;j2
tracks
✓
✓
nj;track
✓
✓
nj;extr
✓
Emiss
T
✓
ηl
✓
ΔRðl; νÞ
✓
ζV
✓
✓
mVV
✓
mVVjj
✓
TABLE III. Variables used for the BDT discriminant in the
resolved analysis category of each lepton channel analysis. TABLE III. Variables used for the BDT discriminant in the
resolved analysis category of each lepton channel analysis. TABLE III. Variables used for the BDT discriminant in the
resolved analysis category of each lepton channel analysis. Variable
0-lepton
1-lepton
2-lepton
mtag
jj
✓
✓
Δηtag
jj
✓
ptag;j1
T
✓
✓
ptag;j2
T
✓
✓
✓
Δηjj
✓
✓
✓
pj1
T
✓
pj2
T
✓
✓
✓
wj1
✓
✓
✓
wj2
✓
✓
✓
nj1
tracks
✓
✓
nj2
tracks
✓
✓
wtag;j1
✓
✓
✓
wtag;j2
✓
✓
✓
ntag;j1
tracks
✓
✓
ntag;j2
tracks
✓
✓
nj;track
✓
✓
nj;extr
✓
Emiss
T
✓
ηl
✓
ΔRðl; νÞ
✓
ζV
✓
✓
mVV
✓
mVVjj
✓
high-purity SR and low-purity SR are merged together for
the BDT training due to an insufficient number of MC
events. VI. MULTIVARIATE ANALYSIS In order to make use of the complete set of
simulated MC events for the BDT training and evaluation
in an unbiased way, the MC events are split for training and
validation into two subsamples of equal size following the
procedure in Ref. [83]. The output distributions of the
BDTs trained on the two subsamples are averaged for both
the simulated and data events. is also used, and it is defined as ζV ¼ minðΔη−; ΔηþÞ,
where Δη−¼ min½ηðVhadÞ;ηðVlepÞ−min½ηtag;j1;ηtag;j2 and
Δηþ ¼ max½ηtag;j1;ηtag;j2−max½ηðVhadÞ;ηðVlepÞ. The vari-
able ζV has large values when the tagging-jets have a large
separation in η, and when the two boson candidates lie
between the tagging-jets in η. Variables sensitive to the
quark–gluon jet separation are also included, such as the
width of the small-R jets (w) [84], and the number of tracks
associated with the jets (ntracks). The number of track jets,
nj;track, and the number of additional small-R jets other than
the Vhad jets and tagging-jets, nj;extr, are also found to be
useful for the BDTs. In the 1-lepton channel, the pseudor-
apidity of the lepton (ηl) is also considered. The input variables used for the BDTs are chosen in
order to maximize the separation between signal and
background, and are summarized in Tables II and III, for
the merged and resolved category, respectively. The dis-
tributions of input variables of the BDTs are compared
between data and simulation, and in general are found to be
in good agreement. The small-R jets are labeled in
decreasing pT as j1 and j2 for the jets used to reconstruct
the hadronically decaying boson, and as “tag, j1” and “tag,
j2” for the tagging-jets. The invariant mass and transverse
momentum of the reconstructed VV (VVjj) system are
denoted by mVV (mVVjj) and pVV
T
(pVVjj
T
), respectively. Angular variables are also considered, such as the pseu-
dorapidity gap between the tagging-jets (Δηtag
jj ) and
between the small-R Vhad jets (Δηjj), the angular separation
of the lepton and neutrino from the W boson decay
(ΔRðl; νÞ) in the 1-lepton channel, and the azimuthal
angle between the directions of ⃗Emiss
T
and the large-R jet
(Δϕð⃗Emiss
T
; JÞ) in the merged category of the 0-lepton
channel. A topological variable named boson centrality VI. MULTIVARIATE ANALYSIS A multivariate method is used to enhance the separation
between the signal and background. The analysis uses the
Toolkit for Multivariate Data Analysis, TMVA [82], and its
implementation of the boosted decision trees (BDTs)
method. BDTs are constructed, trained and evaluated in
each lepton channel and analysis region separately. The
BDT training is carried out using simulated signal and
all background MC samples. However, the events in In the 0-lepton channel, it is not possible to define pure
control regions for W þ jets, Z þ jets and t¯t processes, thus
events falling into the mass sideband regions of the Vhad,
similar to WCRs and ZCRs, form three different CRs
(referred to as VjjCR), one for each of the correspond-
ing SRs. The contribution from multijet production primarily
consists of events with jets or photon conversions 032007-7 PHYS. REV. D 100, 032007 (2019) G. AAD et al. TABLE II. Variables used for the BDT discriminant in the
merged analysis category of each lepton channel. Variable
0-lepton
1-lepton
2-lepton
mtag
jj
✓
✓
Δηtag
jj
✓
ptag;j2
T
✓
✓
✓
mJ
✓
Dðβ¼1Þ
2
✓
✓
Emiss
T
✓
Δϕð⃗Emiss
T
; JÞ
✓
ηl
✓
nj;track
✓
ζV
✓
✓
mVV
✓
pVV
T
✓
mVVjj
✓
pVVjj
T
✓
wtag;j1
✓
wtag;j2
✓
TABLE II. Variables used for the BDT discriminant in the
merged analysis category of each lepton channel. TABLE III. Variables used for the BDT discriminant in the
resolved analysis category of each lepton channel analysis. VIII. SYSTEMATICAL UNCERTAINTIES The sources of systematic uncertainty can be divided into
three categories: experimental uncertainties related to the
detector or to the reconstruction algorithms, uncertainties in
the estimations of background contributions, and uncer-
tainties in modeling the signal. Unless stated otherwise, the
uncertainties quoted below are the uncertainties in the
quantities themselves, not the impact on the analysis
sensitivity. The uncertainty in the integrated luminosity of the
dataset is 2.1%. It is derived from the calibration of the
luminosity scale using x-y beam-separation scans, follow-
ing a methodology similar to that detailed in Ref. [86], and
using the LUCID-2 detector for the baseline luminosity
measurements [87]. This uncertainty is applied to the
normalization of the signal and also to background con-
tributions whose normalizations are derived from MC
simulations. In addition to the luminosity uncertainty, a
variation in the pileup reweighting of MC events is also
included to cover the uncertainty in the ratio of the
predicted to measured inelastic cross sections in Ref. [88]. The uncertainty in the integrated luminosity of the
dataset is 2.1%. It is derived from the calibration of the
luminosity scale using x-y beam-separation scans, follow-
ing a methodology similar to that detailed in Ref. [86], and
using the LUCID-2 detector for the baseline luminosity
measurements [87]. This uncertainty is applied to the
normalization of the signal and also to background con-
tributions whose normalizations are derived from MC
simulations. In addition to the luminosity uncertainty, a
variation in the pileup reweighting of MC events is also
included to cover the uncertainty in the ratio of the
predicted to measured inelastic cross sections in Ref. [88]. The efficiencies of the lepton triggers for events with
selected leptons are high, nearly 100% in the electron
channel and approximately 96% in the muon channel. The
corresponding uncertainties are negligible. For the selec-
tion used in the 0-lepton and 1-lepton channels, the
efficiency of the Emiss
T
trigger is also close to 100% with
negligible associated uncertainty. The modeling of the
electron and muon reconstruction, identification and The
selection
of
hadronically
decaying
bosons
and tagging-jets follows the same steps and apply the
same criteria as for reconstruction level, as shown in
Table IV. For the 0-, 1- and 2-lepton channels, the number of
selected fiducial leptons is required to be 0, 1 and 2,
respectively. Events with additional leptons for the 1- and
2-lepton channels are vetoed. VII. FIDUCIAL CROSS-SECTION DEFINITION The fiducial phase space of the measurement is defined
using stable final-state particles [85]. Leptons produced in
the decay of a hadron or its descendants are not considered
in the charged lepton requirement of the fiducial phase
space. The fiducial selection is summarized in Table IVand
details are given below. 032007-8 PHYS. REV. D 100, 032007 (2019) EARCH FOR ELECTROWEAK DIBOSON PRODUCTION … TABLE IV. Fiducial phase-space definitions used for the measurement of electroweak VVjj production. Object selection
Leptons
pT > 7 GeV, jηj < 2.5
Small-R jets
pT > 20 GeV if jηj < 2.5, and pT > 30 GeV if 2.5 < jηj < 4.5
Large-R jets
pT > 200 GeV, jηj < 2.0
Event selection
Leptonic V selection
0-lepton
Zero leptons, pνν
T > 200 GeV
1-lepton
One lepton with pT > 27 GeV, pν
T > 80 GeV
2-lepton
Two leptons, with leading (subleading) lepton pT > 28ð20Þ GeV
83 < mll < 99 GeV
Hadronic V selection
Merged
One large-R jet, minðjmJ −mWj; jmJ −mZjÞ
64 < mJ < 106 GeV
Resolved
Two small-R jets, minðjmjj −mWj; jmjj −mZjÞ
pj1
T > 40 GeV, pj2
T > 20 GeV
64 < mjj < 106 GeV
Tagging-jets
Two small-R non-b jets, ηtag;j1 · ηtag;j2 < 0, highest mtag
jj
mtag
jj > 400 GeV, ptag;j1;2
T
> 30 GeV
Number of b-jets
0-lepton
1-lepton
0
2-lepton
LE IV. Fiducial phase-space definitions used for the measurement of electroweak VVjj production. Charged leptons are required to satisfy pT > 7 GeV and
jηj < 2.5. Jets are clustered from all final-state particles
except prompt leptons, prompt neutrinos, and prompt
photons using the anti-kt algorithm. Small-R jets are
required to have pT > 20 GeV for jηj < 2.5 and pT >
30 GeV for 2.5 < jηj < 4.5. Jets within ΔR ¼ 0.2 of any
charged lepton (as defined above) are rejected. Jets con-
taining a b-hadron, identified using “truth” information
from the MC event record, are labeled as b-jets. Large-R
jets are required to have pT > 200 GeV and jηj < 2.0, and
the same trimming algorithm as for the reconstruction-level
large-R jets is applied. No Dðβ¼1Þ
2
requirement is applied to
large-R jets. VIII. SYSTEMATICAL UNCERTAINTIES The lepton pT is required to
be larger than 27 GeV for the 1-lepton channel; for the
2-lepton channel, the leading (subleading) lepton pT must
be larger than 28 (20) GeV, and the invariant mass of the
lepton pair must lie within 83 < mll < 99 GeV. For the
0-lepton channel, the transverse momentum of the neutrino
system must satisfy pνν
T > 200 GeV; and for the 1-lepton
channel, the events are required to have pν
T > 80 GeV and
contain no b-jets. The efficiencies of the lepton triggers for events with
selected leptons are high, nearly 100% in the electron
channel and approximately 96% in the muon channel. The
corresponding uncertainties are negligible. For the selec-
tion used in the 0-lepton and 1-lepton channels, the
efficiency of the Emiss
T
trigger is also close to 100% with
negligible associated uncertainty. The modeling of the
electron and muon reconstruction, identification and 032007-9 PHYS. REV. D 100, 032007 (2019) G. AAD et al. 0-lepton channel only. The normalization uncertainties in
the diboson background cross sections are studied with
SHERPA. The uncertainty due to missing higher-order QCD
contributions (QCD scale uncertainty) is estimated by
varying the renormalization (μR) and factorization (μF)
scales independently by a factor ranging from one-half
to two with the constraint 0.5 ≤μF=μR ≤2. The PDF
uncertainty corresponds to the 68% confidence-level var-
iations of the nominal PDF set NNPDF30NNLO, as well as
its difference from the alternative PDF sets CT10NNLO
[92] and MMHT2014NNLO [93]. The overall normaliza-
tion uncertainty for the diboson background is estimated to
be about 30%. For single-top-quark events, a 20% nor-
malization uncertainty is assigned [94]. isolation efficiencies is studied with a tag-and-probe
method using Z →ll events in data and simulation at
ffiffiffis
p ¼ 13 TeV [61,62]. Small corrections are applied to the
simulation to better model the performance seen in data. These corrections have associated uncertainties of the order
of 1%. Uncertainties in the lepton energy (or momentum)
scale and resolution [62,89] are also taken into account. Uncertainties in the jet energy scale and resolution for
small-radius jets are estimated using MC simulation and
in situ techniques [66]. For central jets (jηj < 2.0), the total
uncertainty in the jet energy scale ranges from about 6% for
jets with pT ¼ 25 GeV to about 2% for pT ¼ 1 TeV. VIII. SYSTEMATICAL UNCERTAINTIES There
is also an uncertainty in the jet energy resolution [66],
which ranges from 10% to 20% for jets with a pT of
20 GeV to less than 5% for jets with pT > 200 GeV. Uncertainties in the lepton and jet energy scales and
resolutions are propagated into the uncertainty in Emiss
T
. Uncertainties in the energy scale and resolution of the track
soft term are also propagated into the uncertainty in Emiss
T
[79]. For the b-tagging efficiency of small-R jets, correction
factors are applied to the simulated event samples in order
to compensate for differences between data and simulation. The corrections and uncertainties in the efficiency for
tagging b-jets and in the rejection factor for light jets
are determined from t¯t samples [90,91]. y
g
The uncertainty in the modeling of the final discrimi-
nants, the BDT output and mtag
jj , for background processes
estimated using MC simulation is assessed by comparing
the
nominal
MC
samples
with
alternative
samples. The uncertainties are of the order of 5%–30%. The mtag
jj
reweighting as described in Sec. V B is also included as a
shape systematic uncertainty for Z þ jets and W þ jets
events by taking the difference of their respective final
discriminants before and after applying the reweighting. An
uncertainty in the shape of the BDT or mtag
jj distribution
for the t¯t background is derived by comparing the
POWHEG-BOX sample with the distribution obtained using
MADGRAPH5_AMC@NLO
2.2.2. Additional
systematic
uncertainties are estimated by comparing the nominal
sample showered with PYTHIA 6.428 using the P2012 tune
to one showered with Herwig þ þ 2.7.1 [95] and using the
UEEE5 underlying-event tune [96]. Samples of t¯t events
with the factorization and renormalization scales doubled
or halved are compared with the nominal samples, and the
observed differences are taken as an additional uncertainty. These modeling uncertainties for the t¯t background are
5%–30%. The shape uncertainty for diboson processes is
obtained by comparing MC samples generated by SHERPA
and POWHEG-BOX, and it is found to be of the order of
2%–30%. The shape uncertainty for single-top-quark
events is ignored due to their relatively small contribution
to the total background. The uncertainties in the scale of the large-R jet pT, mass
and Dðβ¼1Þ
2
are of the order of 2%–5%. They are estimated
using comparisons of data and simulation in Ref. [78]. IX. STATISTICAL ANALYSIS The statistical analysis relies on the profile likelihood test
statistic [97] implemented with the RooFit [98] and
RooStats [99] packages. A binned likelihood function
Lðμ; θÞ is constructed as a product of Poisson probabilities
over all of the bins of the fit templates considered in the
analysis. This function depends on the signal-strength
parameter μ, a multiplicative factor applied to the theo-
retical signal production cross section, and θ, a set of
nuisance parameters that encodes the effects of systematic
uncertainties in the signal and expected backgrounds. The
binning is chosen so that the expected numbers of events
ensure that the statistical uncertainty is less than 5% in most
bins, while finer binning is also allowed in signal-enriched
regions. The nuisance parameters are either free to float, or
constrained using Gaussian or log-normal terms defined by
external studies. The likelihood function for the combina-
tion of the three channels is the product of the Poisson
likelihoods of the individual channels. However, only one
constraint term per common nuisance parameter is included
in the product. In general, one SF is introduced for each background
component, common to both the SRs and CRs. One
common Z þ jets SF is used for both the 0-lepton and
2-lepton channels, and one common W þ jets SF is used
for both the 0-lepton and 1-lepton channels. Similarly, one
common t¯t SF is used for both the 0-lepton and 1-lepton
channels. However, independent SFs are used for the
resolved and merged categories, to take into account
different MC modelings in the different phase spaces of
the same background component. The test statistic qμ is defined as the profile likelihood
ratio [100], qμ ¼ −2 ln Λμ with Λμ ¼ Lðμ; ˆˆθμÞ=Lðˆμ; ˆθÞ,
where ˆμ and ˆθ are the values of the parameters that
maximize the likelihood function (with the constraint
0 ≤ˆμ ≤μ), and ˆˆθμ are the values of the nuisance param-
eters that maximize the likelihood function for a given
value of μ. The best-fit signal strength ˆμ value (μobs
EW VVjj) is
obtained by maximizing the likelihood function with
respect to all parameters. To determine whether the
observed data is compatible with the background-only
hypothesis, a test statistic q0 ¼ −2 ln Λ0 is used. p
A simultaneous maximum-likelihood fit is performed to
the observed distributions of the final discriminants, BDT
outputs, in the nine SRs to extract the signal rate informa-
tion. VIII. SYSTEMATICAL UNCERTAINTIES An
absolute uncertainty of 2% is assigned to the large-R jet
energy resolution, and relative uncertainties of 20% and
15% are assigned to the resolution of the large-R jet mass
and Dðβ¼1Þ
2
, respectively. 2
p
y
The overall normalization of the main backgrounds
(W þ jets, Z þ jets and t¯t) is determined from the corre-
sponding data control regions and is left unconstrained and
floating in the global likelihood fit. For W þ jets (Z þ jets)
events in the 0-lepton channel, additional normalization
uncertainties are considered to account for the acceptance
difference between the 0-lepton channel analysis and the
1-lepton (2-lepton) channel analysis, given that there
are no corresponding pure control regions of 0-lepton
events and the normalization is determined mainly from
control regions with 1-lepton (2-lepton) events. This addi-
tional normalization uncertainty for W þ jets (Z þ jets)
events is estimated using the ratio of the event yield in
each signal region of the 0-lepton channel to that in the
1-lepton (2-lepton) channel, and by comparing this ratio
obtained from the nominal MC samples generated by
SHERPA with the ratio from alternative samples generated
by MADGRAPH5_AMC@NLO. The normalization uncer-
tainty is 8% (14%) for W þ jets events in the merged
(resolved) signal region, and 22% (42%) for Z þ jets events
in the merged (resolved) signal region. These uncertainties
are applied to the W þ jets and Z þ jets events in the The following discussion describes the uncertainties in
the predictions of EW VVjj signal processes. The uncer-
tainties in the signal-strength measurement, discussed in
Sec. X A, include contributions from both the normaliza-
tion and shape; for the fiducial cross section measurement,
discussed in Sec. X B, only the shape uncertainties are
taken into account for the measured fiducial cross sections,
and the normalization uncertainties are included for the SM
predicted fiducial cross sections. Theoretical uncertainties for EW VVjj signal pro-
cesses include the PDF choice, the missing higher-order
corrections, and the parton-shower modeling. The signal
modeling uncertainty due to PDF uncertainties is estimated
by taking the uncertainty from the PDF error sets of 032007-10 PHYS. REV. D 100, 032007 (2019) SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … NNPDF23LO and adding it in quadrature to the acceptance
difference obtained using alternative PDF sets: CT10 and
MMHT2014LO. The PDF uncertainties are estimated to be
3%–5%. VIII. SYSTEMATICAL UNCERTAINTIES The parton-shower uncertainty, estimated by
varying relevant parameters in the A14-NNPDF tune
[33], ranges from 1% to 5%. The effect of the QCD scale
uncertainty, of the order of 1%–3%, is estimated by varying
the factorization and renormalization scales independently
by a factor of 2 with the constraint 0.5 ≤μF=μR ≤2. TABLE V. The distributions used in the global likelihood fit for
the signal regions and control regions for all the categories in each
channel. “One bin” implies that a single bin without any shape
information is used in the corresponding fit region. Discriminants
Regions
Merged
high-purity
Merged
low-purity
Resolved
0-lepton
SR
BDT
BDT
BDT
VjjCR
mtag
jj
mtag
jj
mtag
jj
1-lepton
SR
BDT
BDT
BDT
WCR
mtag
jj
mtag
jj
mtag
jj
TopCR
One bin
One bin
One bin
2-lepton
SR
BDT
BDT
BDT
ZCR
mtag
jj
mtag
jj
mtag
jj y
μF=μR
The interference between EW- and QCD-induced VVjj
processes is not included in the MC simulation, since the
EW- and QCD-induced VVjj samples were generated
separately. The interference effect is considered as an
uncertainty affecting both the normalization and the shape
of the EW VVjj kinematic distributions. The effect is
determined using the MADGRAPH5_AMC@NLO 2.4.3 MC
generator at the truth level as a function of mtag
jj . A
reweighting is then applied to the simulated EW VVjj
samples, resulting in shape uncertainties of 5% to 10% at
low and high values of the BDT score, respectively, and a
similar size for the normalization uncertainties. summarized in Table V. Signal and background contribu-
tions, including their shapes in the signal and control
regions, are taken from MC simulations. For each source
of systematic uncertainty, the correlations across bins of
BDT distributions are taken into account and are fully
correlated. The correlations between different regions, as
well as those between signal and background, are also
included. Moreover, normalization scale factors (SFs) are
applied to the MC estimates of the Z þ jets, W þ jets and
top quark contributions. These SFs are free parameters in
the fit and are therefore constrained by the data in both the
signal and control regions. The diboson contribution is
constrained to the theoretical estimate within the corre-
sponding uncertainties. IX. STATISTICAL ANALYSIS The signal is shown as a filled histogram
malized to the signal yield extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram,
gend. The size of the combined statistical and systematic uncertainty for the sum of the fitted signa
atched band. The middle pane shows the ratios of the observed data to the postfit signal and back
shows the ratios of the postfit and pre-fit background predictions. Events / 100 GeV Postfit/Prefit [GeV]
tag
jj
m V
ζ
3
2
1
0
1
2
3
4
Events / 0.5
100
200
300
400
500
600
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
V
ζ
3
−
2
−
1
−
0
1
2
3
4
Postfit/Prefit
0.5
1
1.5 [GeV]
VVjj
m
1000 1500 2000 2500 3000 3500 4000 4500
Events / 100 GeV
1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
[GeV]
VVjj
m
1000
1500
2000
2500
3000
3500
4000
4500
Postfit/Prefit
0.5
1
1.5 Events / 0.5 Postfit/Prefit V
ζ
3
2
1
0
1
2
3
4
Events / 0.5
20
40
60
80
100
120
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
V
ζ
3
−
2
−
1
−
0
1
2
3
4
Postfit/Prefit
0.5
1
1.5 [GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
1
−
10
1
10
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Merged high-purity SR
Data/Postfit
1
2
[GeV]
tag
jj
m
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
1
2 Events / 0.5 Postfit/Prefit FIG. 2. IX. STATISTICAL ANALYSIS [GeV]
miss
T
E
200
300
400
500
600
700
800
Events / 100 GeV
1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
[GeV]
miss
T
E
200
300
400
500
600
700
800
Postfit/Prefit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
1
10
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
0.5
1
1.5
[GeV]
VVjj
m
1000 1500 2000 2500 3000 3500 4000 4500
Events / 100 GeV
1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
[GeV]
VVjj
m
1000
1500
2000
2500
3000
3500
4000
4500
Postfit/Prefit
0.5
1
1.5
V
ζ
3
2
1
0
1
2
3
4
Events / 0.5
100
200
300
400
500
600
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
V
ζ
3
−
2
−
1
−
0
1
2
3
4
Postfit/Prefit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
1
−
10
1
10
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Merged high-purity SR
Data/Postfit
1
2
[G V]
tag
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
1
2
V
ζ
3
2
1
0
1
2
3
4
Events / 0.5
20
40
60
80
100
120
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
ζ
3
−
2
−
1
−
0
1
2
3
4
Postfit/Prefit
0.5
1
1.5 [GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
1
10
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
0.5
1
1.5 [GeV]
miss
T
E
200
300
400
500
600
700
800
Events / 100 GeV
1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
[GeV]
miss
T
E
200
300
400
500
600
700
800
Postfit/Prefit
0.5
1
1.5 [GeV]
miss
T
E
200
300
400
500
600
700
800
Events / 100 GeV
1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
[GeV]
miss
T
E
200
300
400
500
600
700
800
Postfit/Prefit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
1
10
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
0.5
1
1.5
[GeV]
VVjj
m
1000 1500 2000 2500 3000 3500 4000 4500
Events / 100 GeV
1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
[GeV]
VVjj
m
1000
1500
2000
2500
3000
3500
4000
4500
Postfit/Prefit
0.5
1
1.5
V
ζ
3
2
1
0
1
2
3
4
Events / 0.5
100
200
300
400
500
600
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
V
ζ
3
−
2
−
1
−
0
1
2
3
4
Postfit/Prefit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
1
−
10
1
10
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Merged high-purity SR
Data/Postfit
1
2
[GeV]
tag
jj
m
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
1
2
V
ζ
3
2
1
0
1
2
3
4
Events / 0.5
20
40
60
80
100
120
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
V
ζ
3
−
2
−
1
−
0
1
2
3
4
Postfit/Prefit
0.5
1
1.5
ributions for Emiss
T
(top left), mtag
jj (top right), mVVjj (middle left), ζV (middle right), mtag
jj (bottom le
on (top), 1-lepton (middle) and 2-lepton (bottom) channels for the high-purity merged signal regio
r the global likelihood fit are shown as filled histograms. IX. STATISTICAL ANALYSIS The three ZCRs, WCRs and TopCRs as well as the
three VjjCRs are included in the fit’s likelihood calculation;
the mtag
jj
distributions are used for ZCRs, WCRs and
VjjCRs, while for the TopCRs only one bin for each of
the three Vhad decay channels is used. The purpose of using
mtag
jj distributions for CRs is to constrain the mtag
jj reweight-
ing systematic uncertainties. The different regions and the
corresponding discriminants entering the likelihood fit are 032007-11 PHYS. REV. D 100, 032007 (2019) G. AAD et al. IX. STATISTICAL ANALYSIS The distributions for Emiss
T
(top left), mtag
jj (top right), mVVjj (middle left), ζV (middle right), mtag
jj (bottom left), and ζV (bottom
right) in the 0-lepton (top), 1-lepton (middle) and 2-lepton (bottom) channels for the high-purity merged signal region. The background
contributions after the global likelihood fit are shown as filled histograms. The signal is shown as a filled histogram on top of the fitted
backgrounds normalized to the signal yield extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram, scaled by the factor
indicated in the legend. The size of the combined statistical and systematic uncertainty for the sum of the fitted signal and background is
indicated by the hatched band. The middle pane shows the ratios of the observed data to the postfit signal and background predictions. The bottom pane shows the ratios of the postfit and pre-fit background predictions. 032007-12 032007-12 lepton
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
2j
T
p
20
40
60
80
100
120
140
160
180
200
Postfit/Prefit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
10
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
+jets
W
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
0.5
1
1.5
[GeV]
2j
T
p
20
40
60
80
100 120 140 160 180 200
Events / 10 GeV
1
−
10
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
+jets
W
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
2j
T
p
20
40
60
80
100
120
140
160
180
200
Postfit/Prefit
0.5
1
1.5
ibutions for Emiss
T
(top left), mtag
jj (top right), mVVjj (middle left), pj2
T (middle right), mtag
jj (bottom le
pton (top), 1-lepton (middle) and 2-lepton (bottom) channels for the resolved signal region
the global likelihood fit are shown as filled histograms. The signal is shown as a filled histogram
malized to the signal yield extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram,
gend. The size of the combined statistical and systematic uncertainty for the sum of the fitted signal
atched band. The middle pane shows the ratios of the observed data to the postfit signal and backg
shows the ratios of the postfit and prefit background predictions. 032007-12 [GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
10
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
0.5
1
1.5 [GeV]
miss
T
E
200
300
400
500
600
700
800
Events / 100 GeV
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
miss
T
E
200
300
400
500
600
700
800
Postfit/Prefit
0.5
1
1.5 [GeV]
tag
jj
m [GeV]
miss
T
E [GeV]
2j
T
p
20
40
60
80
100 120 140 160 180 200
Events / 10 GeV
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Mis-id. lepton
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
2j
T
p
20
40
60
80
100
120
140
160
180
200
Postfit/Prefit
0.5
1
1.5 [GeV]
VVjj
m
1000 1500 2000 2500 3000 3500 4000 4500
Events / 100 GeV
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Mis-id. 032007-12 PHYS. REV. D 100, 032007 (2019) SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … [GeV]
miss
T
E
200
300
400
500
600
700
800
Events / 100 GeV
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
miss
T
E
200
300
400
500
600
700
800
Postfit/Prefit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
10
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
0.5
1
1.5
[GeV]
VVjj
m
1000 1500 2000 2500 3000 3500 4000 4500
Events / 100 GeV
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Mis-id. lepton
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
VVjj
m
1000
1500
2000
2500
3000
3500
4000
4500
Postfit/Prefit
0.5
1
1.5
[GeV]
2j
T
p
20
40
60
80
100 120 140 160 180 200
Events / 10 GeV
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Mis-id. 032007-12 lepton
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
2j
T
p
20
40
60
80
100
120
140
160
180
200
Postfit/Prefit
0.5
1
1.5
Events / 100 GeV
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
+jets
W
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Resolved SR
Events / 10 GeV
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
+jets
W
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Resolved SR [GeV]
miss
T
E
200
300
400
500
600
700
800
Events / 100 GeV
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
miss
T
E
200
300
400
500
600
700
800
Postfit/Prefit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
10
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
0.5
1
1.5
[GeV]
VVjj
m
1000 1500 2000 2500 3000 3500 4000 4500
Events / 100 GeV
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Mis-id. lepton
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
VVjj
m
1000
1500
2000
2500
3000
3500
4000
4500
Postfit/Prefit
0.5
1
1.5
[GeV]
2j
T
p
20
40
60
80
100 120 140 160 180 200
Events / 10 GeV
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Mis-id. 032007-12 lepton
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
VVjj
m
1000
1500
2000
2500
3000
3500
4000
4500
Postfit/Prefit
0.5
1
1.5 Events / 10 GeV [GeV]
VVjj
m [GeV]
2j
T
p [GeV]
tag
jj
m
500
1000 1500 2000 2500 3000 3500 4000
Events / 100 GeV
10
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
+jets
W
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
tag
jj
m
500
1000
1500
2000
2500
3000
3500
4000
Postfit/Prefit
0.5
1
1.5 [GeV]
2j
T
p
20
40
60
80
100 120 140 160 180 200
Events / 10 GeV
1
−
10
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
+jets
W
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Resolved SR
Data/Postfit
0.5
1
1.5
[GeV]
2j
T
p
20
40
60
80
100
120
140
160
180
200
Postfit/Prefit
0.5
1
1.5 Events / 10 GeV [GeV]
2j
T
p
100
120
1 FIG. 3. The distributions for Emiss
T
(top left), mtag
jj (top right), mVVjj (middle left), pj2
T (middle right), mtag
jj (bottom left), and pj2
T (bottom
right) in the 0-lepton (top), 1-lepton (middle) and 2-lepton (bottom) channels for the resolved signal region. The background
contributions after the global likelihood fit are shown as filled histograms. The signal is shown as a filled histogram on top of the fitted
backgrounds normalized to the signal yield extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram, scaled by the factor
indicated in the legend. The size of the combined statistical and systematic uncertainty for the sum of the fitted signal and background is
indicated by the hatched band. The middle pane shows the ratios of the observed data to the postfit signal and background predictions. The bottom pane shows the ratios of the postfit and prefit background predictions. 032007-13 032007-13 032007-13 PHYS. REV. D 100, 032007 (2019) G. AAD et al. BDT
1
0 8 0 6 0 4 0 2
0
0 2 0 4 0 6 0 8
Events / 0.1
1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
0.8
Postfit/Prefit
0.5
1
1.5
(a)
BDT
1
0 8 0 6 0 4 0 2
0
0 2 0 4 0 6 0 8
Events / 0.1
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Merged low-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
0.8
Postfit/Prefit
0.5
1
1.5
(b)
BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
Events / 0.1
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Resolved SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
Postfit/Prefit
0.5
1
1.5
(c)
Comparisons of the observed data and expected distributions of the BDT outputs of the 0-lepton channel signal regions:
purity and (b) low-purity merged signal regions; (c) the resolved signal region. The background contributions after the global
d fit are shown as filled histograms. The signal is shown as a filled histogram on top of the fitted backgrounds normalized to the
eld extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram, scaled by the factor indicated in the legend. The
overflow are included in the last bin. The middle pane shows the ratios of the observed data to the postfit signal and
nd predictions. The uncertainty in the total prediction, shown as bands, combines statistical and systematic contributions. The
ane shows the ratios of the postfit and prefit background predictions. 032007-13 BDT
1
0 8 0 6 0 4 0 2
0
0 2 0 4 0 6 0 8
Events / 0.1
1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
0.8
Postfit/Prefit
0.5
1
1.5
(a) BDT
1
0 8 0 6 0 4 0 2
0
0 2 0 4 0 6 0 8
Events / 0.1
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Merged low-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
0.8
Postfit/Prefit
0.5
1
1.5
(b) Events / 0.1 (b) BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
Events / 0.1
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
+jets
W
Top Quarks
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
0-lep., Resolved SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
Postfit/Prefit
0.5
1
1.5
(c) (c) FIG. 4. Comparisons of the observed data and expected distributions of the BDT outputs of the 0-lepton channel signal regions:
(a) high-purity and (b) low-purity merged signal regions; (c) the resolved signal region. The background contributions after the global
likelihood fit are shown as filled histograms. The signal is shown as a filled histogram on top of the fitted backgrounds normalized to the
signal yield extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram, scaled by the factor indicated in the legend. The
entries in overflow are included in the last bin. The middle pane shows the ratios of the observed data to the postfit signal and
background predictions. The uncertainty in the total prediction, shown as bands, combines statistical and systematic contributions. The
bottom pane shows the ratios of the postfit and prefit background predictions. X. RESULTS contributions shown are obtained from the signal-plus-
background fits described previously. A. Results for the EW VVjj production processes SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … D 100, 032007 (2019 BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
Events / 0.1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
Postfit/Prefit
0.5
1
1.5
(a)
BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
Events / 0.1
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged low-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
Postfit/Prefit
0.5
1
1.5
(b) BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
Events / 0.1
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged low-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
Postfit/Prefit
0.5
1
1.5
(b) BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
Events / 0.1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
Postfit/Prefit
0.5
1
1.5
(a) Events / 0.1 (b) (a) BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
0 6
Events / 0.1
2
10
3
10
4
10
5
10
6
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Mis-id. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … lepton
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Resolved SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
Postfit/Prefit
0.5
1
1.5
(c) BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
0 6
Events / 0.1
2
10
3
10
4
10
5
10
6
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Mis-id. lepton
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Resolved SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
Postfit/Prefit
0.5
1
1.5
(c)
FIG. 5. Comparisons of the observed data and expected distributions of the BDT outputs of the 1-lepton channel signal regions:
(a) high-purity and (b) low-purity merged signal regions; (c) the resolved signal region. The background contributions after the global
likelihood fit are shown as filled histograms. The signal is shown as a filled histogram on top of the fitted backgrounds normalized to the
signal yield extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram, scaled by the factor indicated in the legend. The
entries in overflow are included in the last bin. The middle pane shows the ratios of the observed data to the postfit signal and
background predictions. The uncertainty in the total prediction, shown as bands, combines statistical and systematic contributions. The
bottom pane shows the ratios of the postfit and prefit background predictions. (c) FIG. 5. Comparisons of the observed data and expected distributions of the BDT outputs of the 1-lepton channel signal regions:
(a) high-purity and (b) low-purity merged signal regions; (c) the resolved signal region. The background contributions after the global
likelihood fit are shown as filled histograms. The signal is shown as a filled histogram on top of the fitted backgrounds normalized to the
signal yield extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram, scaled by the factor indicated in the legend. The
entries in overflow are included in the last bin. The middle pane shows the ratios of the observed data to the postfit signal and
background predictions. The uncertainty in the total prediction, shown as bands, combines statistical and systematic contributions. A. Results for the EW VVjj production processes The observed distributions of the BDT outputs in SRs
used in the global likelihood fit are compared with
the predictions, shown in Fig. 4 for the 0-lepton channel,
Fig. 5 for the 1-lepton channel, and Fig. 6 for the 2-lepton
channel. The data distributions are reasonably well Figures 2 and 3 show a selection of representative postfit
distributions of input variables that are most discriminating
for each of the lepton channels, for the merged and resolved
categories, respectively. Background and EW VVjj signal 032007-14 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … PHYS. REV. D 100, 032007 (2019) BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
Events / 0.1
10
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
Postfit/Prefit
0.5
1
1.5
(a)
BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
Events / 0.1
2
10
3
10
4
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Merged low-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
Postfit/Prefit
0.5
1
1.5
(b)
BDT
1
0 8
0 6
0 4
0 2
0
0 2
0 4
0 6
Events / 0.1
2
10
3
10
4
10
5
10
6
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
W
Mis-id. lepton
Top Quarks
+jets
Z
Diboson
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
1-lep., Resolved SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
Postfit/Prefit
0.5
1
1.5
(c)
FIG. 5. Comparisons of the observed data and expected distributions of the BDT outputs of the 1-lepton channel signal region
(a) high-purity and (b) low-purity merged signal regions; (c) the resolved signal region. The background contributions after the glob
likelihood fit are shown as filled histograms. The signal is shown as a filled histogram on top of the fitted backgrounds normalized to th
signal yield extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram, scaled by the factor indicated in the legend. Th
entries in overflow are included in the last bin. The middle pane shows the ratios of the observed data to the postfit signal an
background predictions. The uncertainty in the total prediction, shown as bands, combines statistical and systematic contributions. Th
bottom pane shows the ratios of the postfit and prefit background predictions. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION …
PHYS. REV. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … The signal is shown as a filled histogram on top of the fitted backgrounds normalized to the
ld extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram, scaled by the factor indicated in the legend. The
overflow are included in the last bin. The middle pane shows the ratios of the observed data to the postfit signal and
nd predictions. The uncertainty in the total prediction, shown as bands, combines statistical and systematic contributions. The
ane shows the ratios of the postfit and prefit background predictions. BDT
1
0 8
0 6
0 4 0 2
0
0 2
0 4
0 6
0 8
Events / 0.1
1
10
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
0.8
Postfit/Prefit
0.5
1
1.5
(a) BDT
1
0 8
0 6
0 4 0 2
0
0 2
0 4
0 6
0 8
Events / 0.1
1
10
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
+jets
W
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Merged low-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
0.8
Postfit/Prefit
0.5
1
1.5
(b) (b) BDT
0 4
0 2
0
0 2
0 4
0 6
0 8
Events / 0.1
10
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
+jets
W
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Resolved SR
Data/Postfit
0.5
1
1.5
BDT
0.4
−
0.2
−
0
0.2
0.4
0.6
0.8
Postfit/Prefit
0.5
1
1.5
(c) (c) FIG. 6. Comparisons of the observed data and expected distributions of the BDT outputs of the 2-lepton channel signal regions:
(a) high-purity and (b) low-purity merged signal regions; (c) the resolved signal region. The background contributions after the global
likelihood fit are shown as filled histograms. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … The
bottom pane shows the ratios of the postfit and prefit background predictions. for the 1-lepton channel, and Table VIII for the 2-lepton
channel. The fitted value of the signal strength is reproduced by the predicted contributions in all cases, with
the smallest p-value of 0.16 from the χ2 test [101] being for
the mtag
jj distribution in the merged high-purity ZCR. The
numbers of events observed and estimated in the SRs are
summarized in Table VI for the 0-lepton channel, Table VII μobs
EW VVjj ¼ 1.05þ0.42
−0.40 ¼ 1.05 0.20ðstat:Þþ0.37
−0.34ðsyst:Þ: 032007-15 PHYS. REV. D 100, 032007 (2019) G. AAD et al. BDT
1
0 8
0 6
0 4 0 2
0
0 2
0 4
0 6
0 8
Events / 0.1
1
10
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Merged high-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
0.8
Postfit/Prefit
0.5
1
1.5
(a)
BDT
1
0 8
0 6
0 4 0 2
0
0 2
0 4
0 6
0 8
Events / 0.1
1
10
2
10
3
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
+jets
W
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Merged low-purity SR
Data/Postfit
0.5
1
1.5
BDT
1
−
0.8
−
0.6
−
0.4
−
0.2
−
0
0.2
0.4
0.6
0.8
Postfit/Prefit
0.5
1
1.5
(b)
BDT
0 4
0 2
0
0 2
0 4
0 6
0 8
Events / 0.1
10
2
10
3
10
4
10
5
10
Data
= 1.05)
μ
(
VVjj
EW
30
×
VVjj
EW
+jets
Z
Diboson
Top Quarks
+jets
W
Uncertainty
ATLAS
-1
= 13 TeV, 35.5 fb
s
2-lep., Resolved SR
Data/Postfit
0.5
1
1.5
BDT
0.4
−
0.2
−
0
0.2
0.4
0.6
0.8
Postfit/Prefit
0.5
1
1.5
(c)
Comparisons of the observed data and expected distributions of the BDT outputs of the 2-lepton channel signal regions:
urity and (b) low-purity merged signal regions; (c) the resolved signal region. The background contributions after the global
d fit are shown as filled histograms. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … TABLE VI. Numbers of events observed and predicted for signal and background processes in the 0-lepton channel signal regions,
obtained from signal-plus-background fits to the signal and control regions (Sec. X). The signal yields are calculated after the fit with the
observed signal strength of 1.05 applied. The uncertainties combine statistical and systematic contributions. The fit constrains the
background estimate towards the observed data, which reduces the total background uncertainty by correlating those uncertainties from
the individual backgrounds. Sample
Resolved
Merged HP
Merged LP
Background
W þ jets
9200 1300
259 27
582 56
Z þ jets
19 000 1400
383 29
955 69
Top quarks
3280 480
277 28
276 32
Diboson
720 120
69 12
68 14
Total
32 100 2000
988 50
1881 96
Signal
WðlνÞWðqq0Þ
56 22
8.0 3.2
5.4 2.2
WðlνÞZðqqÞ
12.0 4.7
2.1 0.8
1.6 0.6
ZðννÞWðqq0Þ
66 25
9.0 3.5
7.4 2.9
ZðννÞZðqqÞ
27 10
5.1 2.0
3.1 1.2
Total
161 35
24.3 5.2
17.5 3.9
SM
32 300 2000
1012 50
1898 96
Data
32 299
1002
1935 TABLE VII. Numbers of events observed and predicted for signal and background processes in the 1-lepton channel signal regions,
obtained from signal-plus-background fits to the signal and control regions (Sec. X). The signal yields are calculated after the fit with the
observed signal strength of 1.05 applied. The uncertainties combine statistical and systematic contributions. The fit constrains the
background estimate towards the observed data, which reduces the total background uncertainty by correlating those uncertainties from
the individual backgrounds. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … The signal is shown as a filled histogram on top of the fitted backgrounds normalized to the
signal yield extracted from data (μ ¼ 1.05), and unstacked as an unfilled histogram, scaled by the factor indicated in the legend. The
entries in overflow are included in the last bin. The middle pane shows the ratios of the observed data to the postfit signal and
background predictions. The uncertainty in the total prediction, shown as bands, combines statistical and systematic contributions. The
bottom pane shows the ratios of the postfit and prefit background predictions. The background-only hypothesis is excluded in data with a
significance of 2.7 standard deviations, compared with 2.5
standard deviations expected. signal-strength parameter. The probability that the signal
strengths measured in the three lepton channels are com-
patible is 36%. Figure 7 shows the measured signal strength from
the combined fit with a single signal-strength fit parameter,
and from a fit where each lepton channel has its own After the global maximum-likelihood fit, the uncertain-
ties described in Sec. VIII are much reduced. The effects of
systematic uncertainties on the measurement after the fit are 032007-16 PHYS. REV. D 100, 032007 (2019) EARCH FOR ELECTROWEAK DIBOSON PRODUCTION … SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Sample
Resolved
Merged HP
Merged LP
Background
W þ jets
69 100 1900
1201 65
2828 97
Z þ jets
2770 370
39 3
83 6
Top quarks
7100 1100
394 56
422 63
Diboson
2660 600
163 35
229 57
Multijet
13 400 1600
Total
95 100 2800
1797 93
3560 130
Signal
WðlνÞWðqq0Þ
330 120
45 17
34 13
WðlνÞZðqqÞ
78 29
11 4
5 2
Total
410 130
57 18
39 13
SM
95 500 2800
1854 95
3600 130
Data
95 366
1864
3571 TABLE VIII. Numbers of events observed and predicted for signal and background processes in the 2-lepton channel signal regions,
obtained from signal-plus-background fits to the signal and control regions (Sec. X). The signal yields are calculated after the fit with the
observed signal strength of 1.05 applied. The uncertainties combine statistical and systematic contributions. The fit constrains the
background estimate towards the observed data, which reduces the total background uncertainty by correlating those uncertainties from
the individual backgrounds. Sample
Resolved
Merged HP
Merged LP
Background
Z þ jets
37 090 310
331 14
775 24
Top quarks
645 99
5.8 0.9
9.9 2.7
Diboson
830 170
34.6 7.6
36.7 8.2
Total
38 570 370
371 16
821 25
Signal
ZðllÞWðqq0Þ
138 53
8.6 3.3
7.0 2.7
ZðllÞZðqqÞ
46 18
4.3 1.7
2.9 1.1
Total
185 56
12.9 3.7
9.8 2.9
SM
38 760 370
384 17
831 25
Data
38 734
371
810 PHYS. REV. D 100, 032007 (2019) G. AAD et al. SM
σ
/
σ
=
μ
Best fit
0
2
4
6
8
10
Combination
0-lepton
1-lepton
2-lepton
1.05 0.40
−
0.42
+
(
0.34
−
0.37
+
0.20
±
)
2.47 1.22
−
1.33
+
(
0.93
−
1.05
+
0.80
±
)
0.33 0.52
−
0.53
+
(
0.46
−
0.47
+
0.25
±
)
1.97 0.77
−
0.83
+
(
0.59
−
0.65
+
0.50
±
)
Tot. ( Stat. Syst. )
Tot. Stat. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … The fitted values of the signal-strength parameter
μobs
EW VVjj for the 0-, 1- and 2-lepton channels and their combi-
nation. The individual μobs
EW VVjj values for the lepton channels are
obtained from a simultaneous fit with the signal-strength param-
eter for each of the lepton channels floating independently. The
probability that the signal strengths measured in the three lepton
channels are compatible is 36%. detailed in Sec. VIII are combined into categories. Apart
from the statistics of the data, the uncertainties with the
largest impact on the sensitivity of EW VVjj production
are from the modeling of background (Z þ jets, W þ jets
and QCD-induced diboson processes), the modeling of
the signal, b-tagging, and reconstruction of small-R and
large-R jets. studied using the signal-strength parameter μobs
EW VVjj. The
relative uncertainties in the best-fit μobs
EW VVjj value from the
leading sources of systematic uncertainty are shown in
Table IX. The individual sources of systematic uncertainty SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … ATLAS
, Observed
-1
=13 TeV, 35.5 fb
s SM
σ
/
σ
=
μ
Best fit
0
2
4
6
8
10
Combination
0-lepton
1-lepton
2-lepton
1.05 0.40
−
0.42
+
(
0.34
−
0.37
+
0.20
±
)
2.47 1.22
−
1.33
+
(
0.93
−
1.05
+
0.80
±
)
0.33 0.52
−
0.53
+
(
0.46
−
0.47
+
0.25
±
)
1.97 0.77
−
0.83
+
(
0.59
−
0.65
+
0.50
±
)
Tot. ( Stat. Syst. )
Tot. Stat. ATLAS
, Observed
-1
=13 TeV, 35.5 fb
s
FIG. 7. The fitted values of the signal-strength parameter
μobs
EW VVjj for the 0-, 1- and 2-lepton channels and their combi-
nation. The individual μobs
EW VVjj values for the lepton channels are
obtained from a simultaneous fit with the signal-strength param-
eter for each of the lepton channels floating independently. The
probability that the signal strengths measured in the three lepton
channels are compatible is 36%. TABLE X. Summary of predicted and measured fiducial cross
sections for EW VVjj production. The three lepton channels are
combined. For the measured fiducial cross sections in the merged
and resolved categories, two signal-strength parameters are used
in the combined fit, one for the merged category and the other one
for the resolved category; while for the measured fiducial cross
section in the inclusive fiducial phase space, a single signal-
strength parameter is used. For the SM predicted cross section,
the error is the theoretical uncertainty (theo.). For the measured
cross section, the first error is the statistical uncertainty (stat.), and
the second error is the systematic uncertainty (syst.). Fiducial
phase space
Predicted
σfid;SM
EW VVjj [fb]
Measured σfid;obs
EW VVjj [fb]
Merged
11.4 0.7 (theo.)
12.7 3.8ðstat:Þþ4.8
−4.2ðsyst:Þ
Resolved
31.6 1.8 (theo.)
26.5 8.2ðstat:Þþ17.4
−17.1ðsyst:Þ
Inclusive
43.0 2.4 (theo.)
45.1 8.6ðstat:Þþ15.9
−14.6ðsyst:Þ FIG. 7. The fitted values of the signal-strength parameter
μobs
EW VVjj for the 0-, 1- and 2-lepton channels and their combi-
nation. The individual μobs
EW VVjj values for the lepton channels are
obtained from a simultaneous fit with the signal-strength param-
eter for each of the lepton channels floating independently. The
probability that the signal strengths measured in the three lepton
channels are compatible is 36%. FIG. 7. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … We acknowledge the support of
ANPCyT, Argentina; Yerevan Physics Institute (YerPhI),
Armenia; ARC, Australia; BMWFW and FWF, Austria;
Azerbaijan National Academy of Sciences (ANAS),
Azerbaijan; State Science and Technology Committee
(SSTC), Belarus; CNPq and FAPESP, Brazil; NSERC,
NRC and CFI, Canada; CERN; CONICYT, Chile; CAS,
MOST and NSFC, China; COLCIENCIAS, Colombia;
MSMT CR, MPO CR and Committee for Collaboration
of the Czech Republic with CERN (VSC CR), Czech
Republic; DNRF and Danish Natural Science Research
Council (DNSRC), Denmark; IN2P3-CNRS, CEA-DRF/
IRFU,
France;
Shota
Rustaveli
National
Science
Foundation of Georgia (SRNSFG), Georgia; BMBF,
HGF, and MPG, Germany; GSRT, Greece; RGC, Hong
Kong SAR, China; ISF and Benoziyo Center, Israel; INFN,
Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO,
Netherlands;
Research
Council
of
Norway
(RCN),
Norway; MNiSW and NCN, Poland; FCT, Portugal;
Ministry of National Education, Institute of Atomic
Physics (MNE/IFA), Romania; Ministry of Education
and Science of the Russian Federation (MES) of Russia
and National Research Centre Kurchatov Institute, Russian
Federation; JINR; Ministry of Education, Science and
Technological Development (MESTD), Serbia; Ministry
of Education, Science, Research and Sport (MSSR),
Slovakia; ARRS and MIZŠ, Slovenia; DST/NRF, South
Africa; MINECO, Spain; Swedish Research Council
(SRC) and Wallenberg Foundation, Sweden; Secretariat
for Education and Research (SERI), SNSF and Cantons of
Bern and Geneva, Switzerland; MOST, Taiwan; TAEK,
Turkey; STFC, United Kingdom; DOE and NSF, United
States of America. In addition, individual groups and
members
have
received
support
from
BCKDF, also reported in Table XI. The measured values are
obtained from a simultaneous fit where each lepton channel
has its own signal-strength parameter, and in each lepton
channel the same signal-strength parameter is applied to
both the merged and resolved categories. The predictions
are from MADGRAPH5_AMC@NLO 2.4.3 at LO only, and no
higher order corrections are included; the theoretical
uncertainties due to the PDF, missing higher-order correc-
tions, and parton-shower modeling are estimated as
described in Sec. VIII. The measured fiducial cross sections
are generally consistent with the SM predictions. XI. CONCLUSION A measurement of VVjj (V ¼ W, Z) electroweak
production using
ffiffiffis
p ¼ 13 TeV pp collisions at the
LHC is presented. The data were collected with the
ATLAS detector in 2015 and 2016 and correspond to a
total integrated luminosity of 35.5 fb−1. The study explores
the final states with one boson decaying leptonically, and
the other boson decaying into a pair of quarks, identified
either as two separate jets or as one large-radius jet. The VVjj electroweak production cross section is
measured with a significance of 2.7 standard deviations
over the background-only hypothesis. The expected sig-
nificance
is
2.5
standard
deviations. The
measured
signal strength relative to the leading-order SM prediction
is μobs
EW VVjj ¼ 1.05 0.20ðstat:Þþ0.37
−0.34ðsyst:Þ. The fiducial
cross section of VVjj electroweak production is measured
to be σfid;obs
EW VVjj ¼ 45.1 8.6ðstat:Þþ15.9
−14.6ðsyst:Þ fb. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … TABLE XI. Summary of predicted and measured fiducial cross sections for EW VVjj production in the three
lepton channels. The measured values are obtained from a simultaneous fit where each lepton channel has its own
signal-strength parameter, and in each lepton channel the same signal-strength parameter is applied to both the
merged and resolved categories. For the SM predicted cross section, the error is the theoretical uncertainty (theo.). For the measured cross section, the first error is the statistical uncertainty (stat.), and the second error is the
systematic uncertainty (syst.). Fiducial phase space
Predicted σfid;SM
EW VVjj [fb]
Measured σfid;obs
EW VVjj [fb]
Merged
0-lepton
4.1 0.3 (theo.)
10.1 3.3ðstat:Þþ4.2
−3.8ðsyst:Þ
1-lepton
6.1 0.5 (theo.)
2.0 1.5ðstat:Þþ2.9
−2.8ðsyst:Þ
2-lepton
1.2 0.1 (theo.)
2.4 0.6ðstat:Þþ0.8
−0.7ðsyst:Þ
Resolved
0-lepton
9.2 0.6 (theo.)
22.8 7.4ðstat:Þþ9.4
−8.5ðsyst:Þ
1-lepton
16.4 1.0 (theo.)
5.5 4.1ðstat:Þþ7.7
−7.5ðsyst:Þ
2-lepton
6.0 0.4 (theo.)
11.8 3.0ðstat:Þþ3.8
−3.5ðsyst:Þ
Inclusive
0-lepton
13.3 0.8 (theo.)
32.9 10.7ðstat:Þþ13.5
−12.3ðsyst:Þ
1-lepton
22.5 1.5 (theo.)
7.5 5.6ðstat:Þþ10.5
−10.2ðsyst:Þ
2-lepton
7.2 0.4 (theo.)
14.2 3.6ðstat:Þþ4.6
−4.2ðsyst:Þ TABLE XI. Summary of predicted and measured fiducial cross sections for EW VVjj production in the three
lepton channels. The measured values are obtained from a simultaneous fit where each lepton channel has its own
signal-strength parameter, and in each lepton channel the same signal-strength parameter is applied to both the
merged and resolved categories. For the SM predicted cross section, the error is the theoretical uncertainty (theo.). For the measured cross section, the first error is the statistical uncertainty (stat.), and the second error is the
systematic uncertainty (syst.). Fiducial phase space
Predicted σfid;SM
EW VVjj [fb]
Measured σfid;obs
EW VVjj [fb]
Merged
0-lepton
4.1 0.3 (theo.)
10.1 3.3ðstat:Þþ4.2
−3.8ðsyst:Þ
1-lepton
6.1 0.5 (theo.)
2.0 1.5ðstat:Þþ2.9
−2.8ðsyst:Þ
2-lepton
1.2 0.1 (theo.)
2.4 0.6ðstat:Þþ0.8
−0.7ðsyst:Þ
Resolved
0-lepton
9.2 0.6 (theo.)
22.8 7.4ðstat:Þþ9.4
−8.5ðsyst:Þ
1-lepton
16.4 1.0 (theo.)
5.5 4.1ðstat:Þþ7.7
−7.5ðsyst:Þ
2-lepton
6.0 0.4 (theo.)
11.8 3.0ðstat:Þþ3.8
−3.5ðsyst:Þ
Inclusive
0-lepton
13.3 0.8 (theo.)
32.9 10.7ðstat:Þþ13.5
−12.3ðsyst:Þ
1-lepton
22.5 1.5 (theo.)
7.5 5.6ðstat:Þþ10.5
−10.2ðsyst:Þ
2-lepton
7.2 0.4 (theo.)
14.2 3.6ðstat:Þþ4.6
−4.2ðsyst:Þ institutions
without
whom
ATLAS
could
not
be
operated efficiently. B. Cross-section measurements The determination of the fiducial cross section is
performed by scaling the measured signal strengths with
the corresponding SM predicted fiducial cross sections,
σfid;obs
EW VVjj ¼ μobs
EW VVjj · σfid;SM
EW VVjj. It is assumed that there is
no new physics that could cause sizable kinematic mod-
ifications of the background and signal. Therefore, the only
new physics signals that can be detected in an unbiased way
are those leading to an enhanced EW VVjj signal strength
in the search region of this analysis. The fiducial cross
sections for EW VVjj are measured in the merged and
resolved fiducial phase-space regions described in Sec. VII
and inclusively. The merged HP SR and LP SR are
combined to form one single merged fiducial phase-space
region. The systematic uncertainties of the measured
fiducial cross sections include contributions from exper-
imental systematic uncertainties, theory modeling uncer-
tainties in the backgrounds, theory modeling uncertainties
in the shapes of signal kinematic distributions, and lumi-
nosity uncertainties. The measured and SM predicted
fiducial cross sections for EW VVjj processes are sum-
marized in Table X, where the measured values are
obtained from two different simultaneous fits. In the first
fit, two signal-strength parameters are used, one for the
merged category (both HP and LP), and the other one for
the resolved category; while in the second fit, a single
signal-strength parameter is used. The measured and SM
predicted fiducial cross sections in each lepton channel are TABLE IX. The symmetrized uncertainty σμ from each source
in the best-fit signal-strength parameter μobs
EW VVjj. The floating
normalizations include uncertainties of normalization scale fac-
tors for Z þ jets, W þ jets and top quark contributions. normalizations include uncertainties of normalization scale fac-
tors for Z þ jets, W þ jets and top quark contributions. Uncertainty source
σμ
Total uncertainty
0.41
Statistical
0.20
Systematic
0.35
Theoretical and modeling uncertainties
Floating normalizations
0.09
Z þ jets
0.13
W þ jets
0.09
t¯t
0.06
Diboson
0.09
Multijet
0.04
Signal
0.07
MC statistics
0.17
Experimental uncertainties
Large-R jets
0.08
Small-R jets
0.06
Leptons
0.02
Emiss
T
0.04
b-tagging
0.07
Pileup
0.04
Luminosity
0.03 032007-18 PHYS. REV. D 100, 032007 (2019) SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … ACKNOWLEDGMENTS [5] ATLAS Collaboration, Measurements of the Higgs boson
production and decay rates and coupling strengths using
pp collision data at
ffiffiffis
p ¼ 7 and 8 TeV in the ATLAS
experiment, Eur. Phys. J. C 76, 6 (2016). [18] CMS Collaboration, Study of Vector Boson Scattering and
Search for New Physics in Events with Two Same-Sign
Leptons and Two Jets, Phys. Rev. Lett. 114, 051801
(2015). [6] ATLAS Collaboration, Study of the spin and parity of the
Higgs boson in diboson decays with the ATLAS detector,
Eur. Phys. J. C 75, 476 (2015); Erratum 76, 152 (2016). [19] CMS Collaboration, Measurement of the cross section for
electroweak production of Zγ in association with two jets
and constraints on anomalous quartic gauge couplings in
proton-proton collisions at
ffiffiffis
p ¼ 8 TeV, Phys. Lett. B
770, 380 (2017). [7] CMS Collaboration, Precise determination of the mass of
the Higgs boson and tests of compatibility of its couplings
with the standard model predictions using proton collisions
at 7 and 8 TeV, Eur. Phys. J. C 75, 212 (2015). [20] CMS Collaboration, Measurement of electroweak WZ
boson production and search for new physics in WZþ
two jets events in pp collisions at
ffiffiffis
p ¼ 13 TeV, Phys. Lett. B 795, 281 (2019). [8] CMS Collaboration, Constraints on the spin-parity and
anomalous HVV couplings of the Higgs boson in proton
collisions at 7 and 8 TeV, Phys. Rev. D 92, 012004 (2015). [9] O. J. P. Eboli, M. C. Gonzalez-Garcia, and S. M. Lietti,
Bosonic quartic couplings at CERN LHC, Phys. Rev. D
69, 095005 (2004). [21] ATLAS Collaboration, Measurements of WZ production
cross sections in pp collisions at
ffiffiffis
p ¼ 8 TeV with the
ATLAS detector and limits on anomalous gauge boson
self-couplings, Phys. Rev. D 93, 092004 (2016). [10] O. J. P. Eboli,
M. C. Gonzalez-Garcia,
and
J. K. Mizukoshi, pp →jjeμνν and jjeμ∓νν at Oðα6emÞ
and Oðα4emα2sÞ for the study of the quartic electroweak
gauge boson vertex at CERN LHC, Phys. Rev. D 74,
073005 (2006). [22] CMS Collaboration, Measurement of vector boson scatter-
ing and constraints on anomalous quartic couplings
from events with four leptons and two jets in proton-
proton collisions at
ffiffiffis
p ¼ 13 TeV, Phys. Lett. B 774, 682
(2017). [11] J. Chang, K. Cheung, C.-T. Lu, and T.-C. Yuan, WW
scattering in the era of post-Higgs-boson discovery, Phys. Rev. D 87, 093005 (2013). ACKNOWLEDGMENTS We thank CERN for the very successful operation of
the LHC, as well as
the support staff from our 032007-19 PHYS. REV. D 100, 032007 (2019) G. AAD et al. CANARIE, CRC and Compute Canada, Canada; COST,
ERC, ERDF, Horizon 2020, and Marie Skłodowska-Curie
Actions, European Union; Investissements d’ Avenir
Labex
and
Idex,
ANR,
France;
DFG
and
AvH
Foundation, Germany; Herakleitos, Thales and Aristeia
programmes co-financed by EU-ESF and the Greek
NSRF,
Greece;
BSF-NSF
and
GIF,
Israel;
CERCA
Programme Generalitat de Catalunya, Spain; The Royal
Society and Leverhulme Trust, United Kingdom. The crucial computing support from all WLCG partners is acknowl-
edged gratefully, in particular from CERN, the ATLAS
Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark,
Norway,
Sweden),
CC-IN2P3
(France),
KIT/GridKA
(Germany), INFN-CNAF (Italy), NL-T1 (Netherlands),
PIC (Spain), ASGC (Taiwan), RAL (UK) and BNL
(USA), the Tier-2 facilities worldwide and large non-
WLCG resource providers. Major contributors of computing
resources are listed in Ref. [102]. [14] CMS Collaboration, Observation of Electroweak Produc-
tion of Same-Sign W Boson Pairs in the Two Jet and Two
Same-Sign Lepton Final State in Proton-Proton Collisions
at 13 TeV, Phys. Rev. Lett. 120, 081801 (2018). [1] B. W. Lee, C. Quigg, and H. B. Thacker, Strength of Weak
Interactions at Very High Energies and the Higgs Boson
Mass, Phys. Rev. Lett. 38, 883 (1977). [2] B. W. Lee, C. Quigg, and H. B. Thacker, Weak interactions
at very high energies: The role of the Higgs-boson mass,
Phys. Rev. D 16, 1519 (1977). [15] ATLAS Collaboration, Observation of electroweak WZ
boson pair production in association with two jets in pp
collisions at
ffiffiffis
p ¼ 13 TeV with the ATLAS detector,
Phys. Lett. B 793, 469 (2019). [3] ATLAS Collaboration, Observation of a new particle in the
search for the standard model Higgs boson with the
ATLAS detector at the LHC, Phys. Lett. B 716, 1 (2012). [16] ATLAS Collaboration, Evidence for Electroweak Produc-
tion of WWjj in pp Collisions at
ffiffiffis
p ¼ 8 TeV with the
ATLAS Detector, Phys. Rev. Lett. 113, 141803 (2014). [4] CMS Collaboration, Observation of a new boson at a mass
of 125 GeV with the CMS experiment at the LHC, Phys. Lett. B 716, 30 (2012). [17] ATLAS Collaboration, Measurements of electroweak Wjj
production and constraints on anomalous gauge couplings
with the ATLAS detector, Eur. Phys. J. C 77, 474 (2017). ACKNOWLEDGMENTS [23] ATLAS Collaboration, Studies of Zγ production in asso-
ciation with a high-mass dijet system in pp collisions at
ffiffiffis
p ¼ 8 TeV with the ATLAS detector, J. High Energy
Phys. 07 (2017) 107. [12] D. Espriu and B. Yencho, Longitudinal WW scattering in
light of the Higgs boson discovery, Phys. Rev. D 87,
055017 (2013). [24] CMS Collaboration, Measurement of electroweak-induced
production of Wγ with two jets in pp collisions at
ffiffiffis
p ¼
8 TeV and constraints on anomalous quartic gauge cou-
plings, J. High Energy Phys. 06 (2017) 106. [13] V. D. Barger, K. Cheung, T. Han, and R. J. N. Phillips,
Strong WþWþ scattering signals at pp supercolliders,
Phys. Rev. D 42, 3052 (1990). 032007-20 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … PHYS. REV. D 100, 032007 (2019) [44] R. Frederix, E. Re, and P. Torrielli, Single-top t-channel
hadroproduction in the four-flavour scheme with POW-
HEG and aMC@NLO, J. High Energy Phys. 09 (2012)
130. [25] CMS Collaboration, Evidence for exclusive γγ →WþW−
production and constraints on anomalous quartic gauge
couplings in pp collisions at
ffiffiffis
p ¼ 7 and 8 TeV, J. High
Energy Phys. 08 (2016) 119. [45] E. Re, Single-top Wt-channel production matched with
parton showers using the POWHEG method, Eur. Phys. J. C 71, 1547 (2011). [26] ATLAS Collaboration, Search for anomalous electroweak
production of WW=WZ in association with a high-mass
dijet system in pp collisions at
ffiffiffis
p ¼ 8 TeV with the
ATLAS detector, Phys. Rev. D 95, 032001 (2017). [46] P. Artoisenet, R. Frederix, O. Mattelaer, and R. Rietkerk,
Automatic spin-entangled decays of heavy resonances
in Monte Carlo simulations, J. High Energy Phys. 03
(2013) 015. [27] CMS Collaboration, Search for anomalous electroweak
production of vector boson pairs in association with two
jets in proton-proton collisions at 13 TeV, arXiv:1905.07445. [47] T. Sjöstrand, S. Mrenna, and P. Z. Skands, PYTHIA 6.4
physics and manual, J. High Energy Phys. 05 (2006) 026. [28] ATLAS Collaboration, The ATLAS experiment at the
CERN large hadron collider, J. Instrum. 3, S08003 (2008). [48] J. Pumplin, D. R. Stump, J. Huston, H.-L. Lai, P. Nadolsky,
and W.-K. Tung, New generation of parton distributions
with uncertainties from global QCD analysis, J. High
Energy Phys. 07 (2002) 012. [29] ATLAS Collaboration, Performance of the ATLAS trigger
system in 2015, Eur. Phys. J. C 77, 317 (2017). [30] J. Alwall, R. Frederix, S. Frixione, V. Hirschi, F. ACKNOWLEDGMENTS Maltoni,
O. Mattelaer, H.-S. Shao, T. Stelzer, P. Torrielli, and M. Zaro, The automated computation of tree-level and next-
to-leading order differential cross sections, and their
matching to parton shower simulations, J. High Energy
Phys. 07 (2014) 079. gy
y
[49] P. Z. Skands, Tuning Monte Carlo generators: The Perugia
tunes, Phys. Rev. D 82, 074018 (2010). [50] D. J. Lange, The EvtGen particle decay simulation pack-
age, Nucl. Instrum. Methods Phys. Res., Sect. A 462, 152
(2001). [31] R. D. Ball et al., Parton distributions with LHC data, Nucl. Phys. B867, 244 (2013). [51] C. Anastasiou, L. J. Dixon, K. Melnikov, and F. Petriello,
High-precision QCD at hadron colliders: Electroweak
gauge boson rapidity distributions at next-to-next-to lead-
ing order, Phys. Rev. D 69, 094008 (2004). [32] T. Sjöstrand, S. Mrenna, and P. Z. Skands, A brief intro-
duction to PYTHIA 8.1, Comput. Phys. Commun. 178, 852
(2008). [52] S. Höche, F. Krauss, M. Schonherr, and F. Siegert, NLO
matrix elements and truncated showers, J. High Energy
Phys. 08 (2011) 123. [33] ATLAS Collaboration, ATLAS Pythia 8 tunes to 7 TeV
data, Report No. ATL-PHYS-PUB-2014-021, 2014, https://
cds.cern.ch/record/1966419. [53] M. Czakon, P. Fiedler, and A. Mitov, Total Top-Quark Pair-
Production Cross Section at Hadron Colliders through
Oðα4sÞ, Phys. Rev. Lett. 110, 252004 (2013). [34] T. Gleisberg, S. Höche, F. Krauss, M. Schönherr, S. Schumann, F. Siegert, and J. Winter, , Event generation
with SHERPA 1.1, J. High Energy Phys. 02 (2009) 007. [54] M. Czakon and A. Mitov, Top++: A program for the
calculation of the top-pair cross-section at hadron colliders,
Comput. Phys. Commun. 185, 2930 (2014). [35] T. Gleisberg and S. Höche, Comix, a new matrix element
generator, J. High Energy Phys. 12 (2008) 039. [36] F. Cascioli, P. Maierhofer, and S. Pozzorini, Scattering
Amplitudes with Open Loops, Phys. Rev. Lett. 108,
111601 (2012). [55] N. Kidonakis, Next-to-next-to-leading logarithm resum-
mation for s-channel single top quark production, Phys. Rev. D 81, 054028 (2010). [37] S. Höche, F. Krauss, M. Schönherr, and F. Siegert, QCD
matrix elements þ parton showers: The NLO case, J. High
Energy Phys. 04 (2013) 027. [56] N. Kidonakis, Two-loop soft anomalous dimensions for
single top quark associated production with a W−or H−,
Phys. Rev. D 82, 054018 (2010). [38] R. D. Ball et al. (NNPDF Collaboration), Parton distribu-
tions for the LHC Run II, J. High Energy Phys. 04 (2015)
040. ACKNOWLEDGMENTS [57] ATLAS Collaboration, The ATLAS Simulation Infrastruc-
ture, Eur. Phys. J. C 70, 823 (2010). [58] S. Agostinelli et al., GEANT4: A simulation toolkit, Nucl. Instrum. Methods Phys. Res., Sect. A 506, 250 (2003). [39] P. Nason, A new method for combining NLO QCD with
shower Monte Carlo algorithms, J. High Energy Phys. 11
(2004) 040. [59] ATLAS Collaboration, Summary of ATLAS Pythia 8
tunes, Report No. ATL-PHYS-PUB-2012-003, 2012,
https://cds.cern.ch/record/1474107. [40] S. Frixione, P. Nason, and G. Ridolfi, A positive-weight
next-to-leading-order Monte Carlo for heavy flavour ha-
droproduction, J. High Energy Phys. 09 (2007) 126. [60] A. D.Martin,W. J.Stirling,R. S.Thorne,andG.Watt,Parton
distributions for the LHC, Eur. Phys. J. C 63, 189 (2009). [41] S. Alioli, P. Nason, C. Oleari, and E. Re, A general
framework for implementing NLO calculations in shower
Monte Carlo programs: The POWHEG BOX, J. High
Energy Phys. 06 (2010) 043. [61] ATLAS Collaboration, Electron reconstruction and iden-
tification in the ATLAS experiment using the 2015 and
2016 LHC proton-proton collision data at
ffiffiffis
p ¼ 13 TeV,
arXiv:1902.04655. [42] H.-L. Lai, M. Guzzi, J. Huston, Z. Li, P. M. Nadolsky, J. Pumplin, and C.-P. Yuan, New parton distributions for
collider physics, Phys. Rev. D 82, 074024 (2010). [62] ATLAS Collaboration, Muon reconstruction performance
of the ATLAS detector in proton-proton collision data at
ffiffiffis
p ¼ 13 TeV, Eur. Phys. J. C 76, 292 (2016). p y
y
[43] S. Alioli, P. Nason, C. Oleari, and E. Re, NLO single-top
production matched with shower in POWHEG: s- and
t-channel contributions, J. High Energy Phys. 09 (2009)
111; Erratum, J. High Energy Phys. 02 (2010) 11. [63] ATLAS Collaboration, Topological cell clustering in the
ATLAS calorimeters and its performance in LHC Run 1,
Eur. Phys. J. C 77, 490 (2017). 032007-21 G. AAD et al. PHYS. REV. D 100, 032007 (2019) [64] M. Cacciari, G. P. Salam, and G. Soyez, The anti-kt jet
clustering algorithm, J. High Energy Phys. 04 (2008) 063. [84] ATLAS Collaboration, Discrimination between light quark
and gluon jets in pp collisions at
ffiffiffis
p ¼ 8 TeV with the
ATLAS Detector, Report No. ATLAS-CONF-2016-034,
2016, https://cds.cern.ch/record/2200202. g
g
g
gy
y
[65] M. Cacciari, G. P. Salam, and G. Soyez, FastJet user
manual, Eur. Phys. J. C 72, 1896 (2012). [66] ATLAS Collaboration, Jet energy scale measurements and
their systematic uncertainties in proton-proton collisions at
ffiffiffis
p ¼ 13 TeV with the ATLAS detector, Phys. ACKNOWLEDGMENTS Rev. D 96,
072002 (2017). [85] ATLAS Collaboration, Proposal for particle-level object
and observable definitions for use in physics measure-
ments at the LHC, Report No. ATL-PHYS-PUB-2015-
013, 2015, https://cds.cern.ch/record/2022743. [67] ATLAS Collaboration, Performance of pile-up mitigation
techniques for jets in pp collisions at
ffiffiffis
p ¼ 8 TeV using
the ATLAS detector, Eur. Phys. J. C 76, 581 (2016). [86] ATLAS Collaboration, Luminosity determination in pp
collisions at
ffiffiffis
p ¼ 8 TeV using the ATLAS detector at the
LHC, Eur. Phys. J. C 76, 653 (2016). [68] M. Cacciari and G. P. Salam, Pileup subtraction using jet
areas, Phys. Lett. B 659, 119 (2008). [87] G. Avoni et al., The new LUCID-2 detector for luminosity
measurement and monitoring in ATLAS, J. Instrum. 13,
P07017 (2018). [69] ATLAS Collaboration, Performance of b-jet identification
in the ATLAS experiment, J. Instrum. 11, P04008 (2016). [88] ATLAS Collaboration, Measurement of the Inelastic Pro-
ton-Proton Cross Section at
ffiffiffis
p ¼ 13 TeV with the AT-
LAS Detector at the LHC, Phys. Rev. Lett. 117, 182002
(2016). [70] ATLAS Collaboration, Optimisation of the ATLAS b-
tagging performance for the 2016 LHC run, Report
No. ATL-PHYS-PUB-2016-012, 2016, https://cds.cern
.ch/record/2160731. [89] ATLAS Collaboration, Electron and photon energy cali-
bration with the ATLAS detector using 2015–2016 LHC
proton-proton collision data, J. Instrum. 14, P03017 (2019). [71] D. Krohn, J. Thaler, and L.-T. Wang, Jet trimming, J. High
Energy Phys. 02 (2010) 084. [72] S. D. Ellis and D. E. Soper, Successive combination jet
algorithm for hadron collisions, Phys. Rev. D 48, 3160
(1993). [90] ATLAS Collaboration, Commissioning of the ATLAS b-
tagging algorithms using t¯t events in early Run 2 data,
Report No. ATL-PHYS-PUB-2015-039, 2015, https://cds
.cern.ch/record/2047871. [73] ATLAS Collaboration, Performance of jet substructure
techniques for large-R jets in proton-proton collisions at
ffiffiffis
p ¼ 7 TeV using the ATLAS detector, J. High Energy
Phys. 09 (2013) 076. [91] ATLAS Collaboration, Expected performance of the AT-
LAS b-tagging algorithms in Run-2, Report No. ATL-
PHYS-PUB-2015-022, 2015, https://cds.cern.ch/record/
2037697. [74] ATLAS Collaboration, Jet mass reconstruction with the
ATLAS Detector in early Run 2 data, Report No. AT-
LAS-CONF-2016-035,
2016,
https://cds.cern.ch/record/
2200211. [92] J. Gao, M. Guzzi, J. Huston, H.-L. Lai, Z. Li, P. Nadolsky,
J. Pumplin, D. Stump, and C.-P. Yuan, CT10 next-to-next-
to-leading order global analysis of QCD, Phys. Rev. D 89,
033009 (2014). ACKNOWLEDGMENTS [75] ATLAS Collaboration, Flavor tagging with track-jets in
boosted topologies with the ATLAS detector, Report
No. ATL-PHYS-PUB-2014-013, 2014, https://cds.cern
.ch/record/1750681. [93] L. A. Harland-Lang, A. D. Martin, P. Motylinski, and R. S. Thorne, Parton distributions in the LHC era: MMHT 2014
PDFs, Eur. Phys. J. C 75, 204 (2015). [76] A. J. Larkoski, I. Moult, and D. Neill, Power counting to
better jet observables, J. High Energy Phys. 12 (2014) 009. [94] ATLAS Collaboration, Measurement of the cross-section
for producing a W boson in association with a single top
quark in pp collisions at
ffiffiffis
p ¼ 13 TeV with ATLAS, J. High Energy Phys. 01 (2018) 063. [77] A. J. Larkoski, I. Moult, and D. Neill, Analytic boosted
boson discrimination, J. High Energy Phys. 05 (2016) 117. [95] G. Corcella, I. G. Knowles, G. Marchesini, S. Moretti, K. Odagiri, P. Richardson, M. H. Seymour, and B. R. Webber,
HERWIG 6: An event generator for hadron emission
reactions with interfering gluons (including supersymmet-
ric processes), J. High Energy Phys. 01 (2001) 010. [78] ATLAS Collaboration, Performance of top-quark and W-
boson tagging with ATLAS in Run 2 of the LHC, Eur. Phys. J. C 79, 375 (2019). [79] ATLAS Collaboration, Performance of missing transverse
momentum reconstruction with the ATLAS detector using
proton-proton collisions at
ffiffiffis
p ¼ 13 TeV, Eur. Phys. J. C
78, 903 (2018). [96] S. Gieseke, C. Rohr, and A. Siodmok, Colour reconnec-
tions in Herwig++, Eur. Phys. J. C 72, 2225 (2012). [80] ATLAS Collaboration, Searches for heavy ZZ and ZW
resonances in the llqq and ννqq final states in pp
collisions at
ffiffiffis
p ¼ 13 TeV with the ATLAS detector, J. High Energy Phys. 03 (2018) 009. [97] ATLAS Collaboration, Combined search for the Standard
Model Higgs boson in pp collisions at
ffiffiffis
p ¼ 7 TeV with
the ATLAS detector, Phys. Rev. D 86, 032003 (2012). [98] W. Verkerke and D. P. Kirkby, The RooFit toolkit for data
modeling, arXiv:physics/0306116. [81] ATLAS Collaboration, Search for WW=WZ resonance
production in lνqq final states in pp collisions at
ffiffiffis
p ¼
13 TeV with the ATLAS detector, J. High Energy Phys. 03
(2018) 042. [99] L. Moneta, K. Belasco, K. Cranmer, S. Kreiss, A. Lazzaro,
D. Piparo, G. Schott, W. Verkerke, M. Wolf, The RooStats
Project,
Proc. Sci.,
ACAT2010 (2010) 057 [arXiv:
1009.1003]. [82] A. Hoecker et al., TMVA: Toolkit for multivariate data
analysis, arXiv:physics/0703039. ACKNOWLEDGMENTS ¯ [100] ATLAS Collaboration, Procedure for the LHC Higgs
boson search combination in summer 2011, Report
No. ATL-PHYS-PUB-2011-011, 2011, https://cds.cern
.ch/record/1375842. [83] ATLAS Collaboration, Evidence for the H →b¯b decay
with the ATLAS detector, J. High Energy Phys. 12 (2017)
024. 032007-22 [102] ATLAS Collaboration, ATLAS computing acknowledge-
ments, Report No. ATL-GEN-PUB-2016-002, https://cds
.cern.ch/record/2202407. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Becker,
C. Becot,
A. Beddall,12d A. J. Beddall,12a V. A. Bednyakov,79 M. Bedognetti,120 C. P. Bee,155 T. A. Beermann,76 M. Begalli,80b
M. Begel,29 A. Behera,155 J. K. Behr,46 F. Beisiegel,24 A. S. Bell,94 G. Bella,161 L. Bellagamba,23b A. Bellerive,34 P. Bellos,9
K. Beloborodov,122b,122a K. Belotskiy,112 N. L. Belyaev,112 D. Benchekroun,35a N. Benekos,10 Y. Benhammou,161
D. P. Benjamin,6 M. Benoit,54 J. R. Bensinger,26 S. Bentvelsen,120 L. Beresford,135 M. Beretta,51 D. Berge,46 ,
,
y
,
g
,
,
,
g
,
M. Begel,29 A. Behera,155 J. K. Behr,46 F. Beisiegel,24 A. S. Bell,94 G. Bella,161 L. Bellagamba,23b A. Bellerive,34 P. Bellos,9
K. Beloborodov,122b,122a K. Belotskiy,112 N. L. Belyaev,112 D. Benchekroun,35a N. Benekos,10 Y. Benhammou,161
D P Benjamin 6 M Benoit 54 J R Bensinger 26 S Bentvelsen 120 L Beresford 135 M Beretta 51 D Berge 46 M. Begel,29 A. Behera,155 J. K. Behr,46 F. Beisiegel,24 A. S. Bell,94 G. Bella,161 L. Bellagamba,23b A. Bellerive,34 P. Bellos,9
K. Beloborodov,122b,122a K. Belotskiy,112 N. L. Belyaev,112 D. Benchekroun,35a N. Benekos,10 Y. Benhammou,161
D. P. Benjamin,6 M. Benoit,54 J. R. Bensinger,26 S. Bentvelsen,120 L. Beresford,135 M. Beretta,51 D. Berge,46 j
g
g
E. Bergeaas Kuutmann,172 N. Berger,5 B. Bergmann,142 L. J. Bergsten,26 J. Beringer,18 S. Berlendis,7 N. R. Bernard,102
136
153
24
93
99
15
89
40 E. Bergeaas Kuutmann,172 N. Berger,5 B. Bergmann,142 L. J. Bergsten,26 J. Beringer,18 S. Berlendis,7 N. R. Bernard,102
G. Bernardi,136 C. Bernius,153 F. U. Bernlochner,24 T. Berry,93 P. Berta,99 C. Bertella,15a I. A. Bertram,89 G. J. Besjes,40
O. Bessidskaia Bylund,182 N. Besson,145 A. Bethani,100 S. Bethke,115 A. Betti,24 A. J. Bevan,92 J. Beyer,115 R. Bi,139
R. M. Bianchi,139 O. Biebel,114 D. Biedermann,19 R. Bielski,36 K. Bierwagen,99 N. V. Biesuz,71a,71b M. Biglietti,74a
T. R. V. Billoud,109 M. Bindi,53 A. Bingul,12d C. Bini,72a,72b S. Biondi,23b,23a M. Birman,180 T. Bisanz,53 J. P. Biswal,161
A. Bitadze,100 C. Bittrich,48 K. Bjørke,134 K. M. Black,25 T. Blazek,28a I. Bloch,46 C. Blocker,26 A. Blue,57
U. Blumenschein,92 G. J. Bobbink,120 V. S. Bobrovnikov,122b,122a S. S. Bocchetta,96 A. Bocci,49 D. Boerner,46 D. Bogavac,14
A. G. Bogdanchikov,122b,122a C. Bohm,45a V. Boisvert,93 P. Bokan,53,172 T. Bold,83a A. S. Boldyrev,113 A. E. Bolz,61b
M. Bomben,136 M. Bona,92 J. S. Bonilla,131 M. Boonekamp,145 H. M. Borecka-Bielska,90 A. Borisov,123 G. Borissov,89
J. Bortfeldt,36 D. Bortoletto,135 V. Bortolotto,73a,73b D. Boscherini,23b M. Bosman,14 J. D. Bossio Sola,103 K. Bouaouda,35a G. Bernardi,136 C. Bernius,153 F. U. Bernlochner,24 T. Berry,93 P. Berta,99 C. Bertella,15a I. [101] N. D. Gagunashvili, Comparison of weighted and un-
weighted histograms, Proc. Sci., ACAT2007 (2007) 054
[arXiv:physics/0605123]. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Avramidou,60a M. K. Ayoub,15a A. M. Azoulay,168b G. Azuelos,109,e
M. J. Baca,21 H. Bachacou,145 K. Bachas,67a,67b M. Backes,135 F. Backman,45a,45b P. Bagnaia,72a,72b M. Bahmani,84
H. Bahrasemani,152 A. J. Bailey,174 V. R. Bailey,173 J. T. Baines,144 M. Bajic,40 C. Bakalis,10 O. K. Baker,183 P. J. Bakker,120
D. Bakshi Gupta,8 S. Balaji,157 E. M. Baldin,122b,122a P. Balek,180 F. Balli,145 W. K. Balunas,135 J. Balz,99 E. Banas,84
A Bandyopadhyay 24 Sw Banerjee 181,f A A E Bannoura 182 L Barak 161 W M Barbe 38 E L Barberio 104 ,
y,
y,
,
j ,
,
,
,
D. Bakshi Gupta,8 S. Balaji,157 E. M. Baldin,122b,122a P. Balek,180 F. Balli,145 W. K. Balunas,135 J. Balz,99 E. Banas,84
A. Bandyopadhyay,24 Sw. Banerjee,181,f A. A. E. Bannoura,182 L. Barak,161 W. M. Barbe,38 E. L. Barberio,104 D. Barberis,
,
M. Barbero,
T. Barillari,
M-S. Barisits,
J. Barkeloo,
T. Barklow,
R. Barnea,
S. L. Barnes,
B. M. Barnett,144 R. M. Barnett,18 Z. Barnovska-Blenessy,60a A. Baroncelli,60a G. Barone,29 A. J. Barr,135
L. Barranco Navarro,174 F. Barreiro,98 J. Barreiro Guimarães da Costa,15a S. Barsov,138 R. Bartoldus,153 G. Bartolini,101 A. E. Barton,89 P. Bartos,28a A. Basalaev,46 A. Bassalat,132,g R. L. Bates,57 S. J. Batista,167 S. Batlamous,35e J. R. Batley,32
151
146
72 72b
145
171
31 h
49
136 s,28a A. Basalaev,46 A. Bassalat,132,g R. L. Bates,57 S. J. Batista,167 S. Batlamous,35e J. R. Batley rton,89 P. Bartos,28a A. Basalaev,46 A. Bassalat,132,g R. L. Bates,57 S. J. Batista,167 S. Batlamous y
B. Batool,151 M. Battaglia,146 M. Bauce,72a,72b F. Bauer,145 K. T. Bauer,171 H. S. Bawa,31,h J. B. Beacham,49 T. Beau,136
P H Beauchemin 170 F Becherer 52 P Bechtle 24 H C Beck 53 H P Beck 20,i K Becker 52 M Becker 99 C Becot 46 glia,146 M. Bauce,72a,72b F. Bauer,145 K. T. Bauer,171 H. S. Bawa,31,h J. B. Beacham,49 T. Beau,1 B. Batool,151 M. Battaglia,146 M. Bauce,72a,72b F. Bauer,145 K. T. Bauer,171 H. S. Bawa,31,h J. B. Beacham,49 T. Beau,136
h
i
170
h
52
h l
24
C
k 53
k 20 i
k
52
k
99 C
46 B. Batool,
M. Battaglia,
M. Bauce,
,
F. Bauer,
K. T. Bauer,
H. S. Bawa,
, J. B. Beacham,
T. Beau,
P. H. Beauchemin,170 F. Becherer,52 P. Bechtle,24 H. C. Beck,53 H. P. Beck,20,i K. Becker,52 M. Becker,99 C. Becot,46 P. H. Beauchemin,
F. Becherer,
P. Bechtle,
H. C. Beck,
H. P. Beck,
, K. Becker,
M. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Azuelos,109,e
M. J. Baca,21 H. Bachacou,145 K. Bachas,67a,67b M. Backes,135 F. Backman,45a,45b P. Bagnaia,72a,72b M. Bahmani,84
H. Bahrasemani,152 A. J. Bailey,174 V. R. Bailey,173 J. T. Baines,144 M. Bajic,40 C. Bakalis,10 O. K. Baker,183 P. J. Bakker,120
D. Bakshi Gupta,8 S. Balaji,157 E. M. Baldin,122b,122a P. Balek,180 F. Balli,145 W. K. Balunas,135 J. Balz,99 E. Banas,84
A. Bandyopadhyay,24 Sw. Banerjee,181,f A. A. E. Bannoura,182 L. Barak,161 W. M. Barbe,38 E. L. Barberio,104
55b 55
101
115
36
131
153
160
60 G. Aad,101 B. Abbott,128 D. C. Abbott,102 O. Abdinov,13,a A. Abed Abud,70a,70b K. Abeling,53 D. K. Abhayasinghe,93
S. H. Abidi,167 O. S. AbouZeid,40 N. L. Abraham,156 H. Abramowicz,161 H. Abreu,160 Y. Abulaiti,6 B. S. Acharya,66a,66b,b
B. Achkar,53 S. Adachi,163 L. Adam,99 C. Adam Bourdarios,132 L. Adamczyk,83a L. Adamek,167 J. Adelman,121
M. Adersberger,114 A. Adiguzel,12c,c S. Adorni,54 T. Adye,144 A. A. Affolder,146 Y. Afik,160 C. Agapopoulou,132
M. N. Agaras,38 A. Aggarwal,119 C. Agheorghiesei,27c J. A. Aguilar-Saavedra,140f,140a,d F. Ahmadov,79 X. Ai,15a
G. Aielli,73a,73b S. Akatsuka,85 T. P. A. Åkesson,96 E. Akilli,54 A. V. Akimov,110 K. Al Khoury,132 G. L. Alberghi,23b,23a
J. Albert,176 M. J. Alconada Verzini,88 S. Alderweireldt,119 M. Aleksa,36 I. N. Aleksandrov,79 C. Alexa,27b D. Alexandre,19
T. Alexopoulos,10 A. Alfonsi,120 M. Alhroob,128 B. Ali,142 G. Alimonti,68a J. Alison,37 S. P. Alkire,148 C. Allaire,132
B. M. M. Allbrooke,156 B. W. Allen,131 P. P. Allport,21 A. Aloisio,69a,69b A. Alonso,40 F. Alonso,88 C. Alpigiani,148
A. A. Alshehri,57 M. Alvarez Estevez,98 B. Alvarez Gonzalez,36 D. Álvarez Piqueras,174 M. G. Alviggi,69a,69b
Y. Amaral Coutinho,80b A. Ambler,103 L. Ambroz,135 C. Amelung,26 D. Amidei,105 S. P. Amor Dos Santos,140a
S. Amoroso,46 C. S. Amrouche,54 F. An,78 C. Anastopoulos,149 N. Andari,145 T. Andeen,11 C. F. Anders,61b J. K. Anders,20
A. Andreazza,68a,68b V. Andrei,61a C. R. Anelli,176 S. Angelidakis,38 A. Angerami,39 A. V. Anisenkov,122b,122a A. Annovi,71a
C. Antel,61a M. T. Anthony,149 M. Antonelli,51 D. J. A. Antrim,171 F. Anulli,72a M. Aoki,81 J. A. Aparisi Pozo,174
L. Aperio Bella,36 G. Arabidze,106 J. P. Araque,140a V. Araujo Ferraz,80b R. Araujo Pereira,80b C. Arcangeletti,51
A. T. H. Arce,49 F. A. Arduh,88 J-F. Arguin,109 S. Argyropoulos,77 J.-H. Arling,46 A. J. Armbruster,36 L. J. Armitage,92
A. Armstrong,171 O. Arnaez,167 H. Arnold,120 A. Artamonov,111,a G. Artoni,135 S. Artz,99 S. Asai,163 N. Asbah,59
E. M. Asimakopoulou,172 L. Asquith,156 K. Assamagan,29 R. Astalos,28a R. J. Atkin,33a M. Atkinson,173 N. B. Atlay,151
H. Atmani,132 K. Augsten,142 G. Avolio,36 R. Avramidou,60a M. K. Ayoub,15a A. M. Azoulay,168b G. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … PHYS. REV. D 100, 032007 (2019) [101] N. D. Gagunashvili, Comparison of weighted and un-
weighted histograms, Proc. Sci., ACAT2007 (2007) 054
[arXiv:physics/0605123]. [102] ATLAS Collaboration, ATLAS computing acknowledge-
ments, Report No. ATL-GEN-PUB-2016-002, https://cds
.cern.ch/record/2202407. [101] N. D. Gagunashvili, Comparison of weighted and un-
weighted histograms, Proc. Sci., ACAT2007 (2007) 054
[arXiv:physics/0605123]. [102] ATLAS Collaboration, ATLAS computing acknowledge-
ments, Report No. ATL-GEN-PUB-2016-002, https://cds
.cern.ch/record/2202407. [101] N. D. Gagunashvili, Comparison of weighted and un-
weighted histograms, Proc. Sci., ACAT2007 (2007) 054
[arXiv:physics/0605123]. G. Aad,101 B. Abbott,128 D. C. Abbott,102 O. Abdinov,13,a A. Abed Abud,70a,70b K. Abeling,53 D. K. Abhayasinghe,93
S. H. Abidi,167 O. S. AbouZeid,40 N. L. Abraham,156 H. Abramowicz,161 H. Abreu,160 Y. Abulaiti,6 B. S. Acharya,66a,66b,b
B. Achkar,53 S. Adachi,163 L. Adam,99 C. Adam Bourdarios,132 L. Adamczyk,83a L. Adamek,167 J. Adelman,121
M. Adersberger,114 A. Adiguzel,12c,c S. Adorni,54 T. Adye,144 A. A. Affolder,146 Y. Afik,160 C. Agapopoulou,132
M. N. Agaras,38 A. Aggarwal,119 C. Agheorghiesei,27c J. A. Aguilar-Saavedra,140f,140a,d F. Ahmadov,79 X. Ai,15a
G. Aielli,73a,73b S. Akatsuka,85 T. P. A. Åkesson,96 E. Akilli,54 A. V. Akimov,110 K. Al Khoury,132 G. L. Alberghi,23b,23a
J. Albert,176 M. J. Alconada Verzini,88 S. Alderweireldt,119 M. Aleksa,36 I. N. Aleksandrov,79 C. Alexa,27b D. Alexandre,19
T. Alexopoulos,10 A. Alfonsi,120 M. Alhroob,128 B. Ali,142 G. Alimonti,68a J. Alison,37 S. P. Alkire,148 C. Allaire,132
B. M. M. Allbrooke,156 B. W. Allen,131 P. P. Allport,21 A. Aloisio,69a,69b A. Alonso,40 F. Alonso,88 C. Alpigiani,148
A. A. Alshehri,57 M. Alvarez Estevez,98 B. Alvarez Gonzalez,36 D. Álvarez Piqueras,174 M. G. Alviggi,69a,69b
Y. Amaral Coutinho,80b A. Ambler,103 L. Ambroz,135 C. Amelung,26 D. Amidei,105 S. P. Amor Dos Santos,140a
S. Amoroso,46 C. S. Amrouche,54 F. An,78 C. Anastopoulos,149 N. Andari,145 T. Andeen,11 C. F. Anders,61b J. K. Anders,20
A. Andreazza,68a,68b V. Andrei,61a C. R. Anelli,176 S. Angelidakis,38 A. Angerami,39 A. V. Anisenkov,122b,122a A. Annovi,71a
C. Antel,61a M. T. Anthony,149 M. Antonelli,51 D. J. A. Antrim,171 F. Anulli,72a M. Aoki,81 J. A. Aparisi Pozo,174
L. Aperio Bella,36 G. Arabidze,106 J. P. Araque,140a V. Araujo Ferraz,80b R. Araujo Pereira,80b C. Arcangeletti,51
A. T. H. Arce,49 F. A. Arduh,88 J-F. Arguin,109 S. Argyropoulos,77 J.-H. Arling,46 A. J. Armbruster,36 L. J. Armitage,92
A. Armstrong,171 O. Arnaez,167 H. Arnold,120 A. Artamonov,111,a G. Artoni,135 S. Artz,99 S. Asai,163 N. Asbah,59
E. M. Asimakopoulou,172 L. Asquith,156 K. Assamagan,29 R. Astalos,28a R. J. Atkin,33a M. Atkinson,173 N. B. Atlay,151
H. Atmani,132 K. Augsten,142 G. Avolio,36 R. Avramidou,60a M. K. Ayoub,15a A. M. Azoulay,168b G. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Azuelos,109,e
M. J. Baca,21 H. Bachacou,145 K. Bachas,67a,67b M. Backes,135 F. Backman,45a,45b P. Bagnaia,72a,72b M. Bahmani,84
H. Bahrasemani,152 A. J. Bailey,174 V. R. Bailey,173 J. T. Baines,144 M. Bajic,40 C. Bakalis,10 O. K. Baker,183 P. J. Bakker,120
D. Bakshi Gupta,8 S. Balaji,157 E. M. Baldin,122b,122a P. Balek,180 F. Balli,145 W. K. Balunas,135 J. Balz,99 E. Banas,84
A. Bandyopadhyay,24 Sw. Banerjee,181,f A. A. E. Bannoura,182 L. Barak,161 W. M. Barbe,38 E. L. Barberio,104
D. Barberis,55b,55a M. Barbero,101 T. Barillari,115 M-S. Barisits,36 J. Barkeloo,131 T. Barklow,153 R. Barnea,160 S. L. Barnes,60c G. Aad,101 B. Abbott,128 D. C. Abbott,102 O. Abdinov,13,a A. Abed Abud,70a,70b K. Abeling,53 D. K. Abhayasinghe,93
S. H. Abidi,167 O. S. AbouZeid,40 N. L. Abraham,156 H. Abramowicz,161 H. Abreu,160 Y. Abulaiti,6 B. S. Acharya,66a,66b,b
B. Achkar,53 S. Adachi,163 L. Adam,99 C. Adam Bourdarios,132 L. Adamczyk,83a L. Adamek,167 J. Adelman,121
M. Adersberger,114 A. Adiguzel,12c,c S. Adorni,54 T. Adye,144 A. A. Affolder,146 Y. Afik,160 C. Agapopoulou,132
M. N. Agaras,38 A. Aggarwal,119 C. Agheorghiesei,27c J. A. Aguilar-Saavedra,140f,140a,d F. Ahmadov,79 X. Ai,15a
G. Aielli,73a,73b S. Akatsuka,85 T. P. A. Åkesson,96 E. Akilli,54 A. V. Akimov,110 K. Al Khoury,132 G. L. Alberghi,23b,23a
J. Albert,176 M. J. Alconada Verzini,88 S. Alderweireldt,119 M. Aleksa,36 I. N. Aleksandrov,79 C. Alexa,27b D. Alexandre,19
T. Alexopoulos,10 A. Alfonsi,120 M. Alhroob,128 B. Ali,142 G. Alimonti,68a J. Alison,37 S. P. Alkire,148 C. Allaire,132
B. M. M. Allbrooke,156 B. W. Allen,131 P. P. Allport,21 A. Aloisio,69a,69b A. Alonso,40 F. Alonso,88 C. Alpigiani,148
A. A. Alshehri,57 M. Alvarez Estevez,98 B. Alvarez Gonzalez,36 D. Álvarez Piqueras,174 M. G. Alviggi,69a,69b
Y. Amaral Coutinho,80b A. Ambler,103 L. Ambroz,135 C. Amelung,26 D. Amidei,105 S. P. Amor Dos Santos,140a
S. Amoroso,46 C. S. Amrouche,54 F. An,78 C. Anastopoulos,149 N. Andari,145 T. Andeen,11 C. F. Anders,61b J. K. Anders,20
A. Andreazza,68a,68b V. Andrei,61a C. R. Anelli,176 S. Angelidakis,38 A. Angerami,39 A. V. Anisenkov,122b,122a A. Annovi,71a
C. Antel,61a M. T. Anthony,149 M. Antonelli,51 D. J. A. Antrim,171 F. Anulli,72a M. Aoki,81 J. A. Aparisi Pozo,174
L. Aperio Bella,36 G. Arabidze,106 J. P. Araque,140a V. Araujo Ferraz,80b R. Araujo Pereira,80b C. Arcangeletti,51
A. T. H. Arce,49 F. A. Arduh,88 J-F. Arguin,109 S. Argyropoulos,77 J.-H. Arling,46 A. J. Armbruster,36 L. J. Armitage,92
A. Armstrong,171 O. Arnaez,167 H. Arnold,120 A. Artamonov,111,a G. Artoni,135 S. Artz,99 S. Asai,163 N. Asbah,59
E. M. Asimakopoulou,172 L. Asquith,156 K. Assamagan,29 R. Astalos,28a R. J. Atkin,33a M. Atkinson,173 N. B. Atlay,151
H. Atmani,132 K. Augsten,142 G. Avolio,36 R. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Ciocio,18 F. Cirotto,69a,69b
Z. H. Citron,180 M. Citterio,68a D. A. Ciubotaru,27b B. M. Ciungu,167 A. Clark,54 M. R. Clark,39 P. J. Clark,50
C. Clement,45a,45b Y. Coadou,101 M. Cobal,66a,66c A. Coccaro,55b J. Cochran,78 H. Cohen,161 A. E. C. Coimbra,36
L. Colasurdo,119 B. Cole,39 A. P. Colijn,120 J. Collot,58 P. Conde Muiño,140a,n E. Coniavitis,52 S. H. Connell,33b
I A Connelly 57 S Constantinescu 27b F Conventi 69a,o A M Cooper Sarkar 135 F Cormier 175 K J R Cormier 167 Cole,39 A. P. Colijn,120 J. Collot,58 P. Conde Muiño,140a,n E. Coniavitis,52 S. H. Connell,33b I. A. Connelly,57 S. Constantinescu,27b F. Conventi,69a,o A. M. Cooper-Sarkar,135 F. Cormier,175 K. J. R. Cormier,167
L D Corpe 94 M Corradi 72a,72b E E Corrigan 96 F Corriveau 103,p A Cortes Gonzalez 36 M J Costa 174 F Costanza 5 Cr´ep´e-Renaudin,58 F. Crescioli,136 M. Cristinziani,24 V. Croft,120 G. Crosetti,41b,41a A. Cueto,5 T. Cuhadar Donszelmann,149 A. R. Cukierman,153 S. Czekierda,84 P. Czodrowski,36 M. J. Da Cunha Sargedas De Sousa,60b J. V. Da Fonseca Pinto,80b C. Da Via,100 W. Dabrowski,83a T. Dado,28a S. Dahbi,35e T. Dai,105 C. Dallapiccola,102 M. Dam,40
G. D’amen,23b,23a V. D’Amico,74a,74b J. Damp,99 J. R. Dandoy,137 M. F. Daneri,30 N. P. Dang,181,f N. D Dann,100
M. Danninger,175 V. Dao,36 G. Darbo,55b O. Dartsi,5 A. Dattagupta,131 T. Daubney,46 S. D’Auria,68a,68b W. Davey,24
C D
id 46 T D
id k 143 D R D
i
49 E D
104 I D
149 K D
8 R D A
di
69a M D B
120 C
v ,
v
,
v ,
w ,
w
,
,
,
,
S. De Castro,23b,23a S. De Cecco,72a,72b N. De Groot,119 P. de Jong,120 H. De la Torre,106 A. De Maria,15c D. De Pedis,72a 3b,23a S. De Cecco,72a,72b N. De Groot,119 P. de Jong,120 H. De la Torre,106 A. De Maria,15c D. D Salvo,72a U. De Sanctis,73a,73b M. De Santis,73a,73b A. De Santo,156 K. De Vasconcelos Corga
132
146
9
42
41b 41 J. B. De Vivie De Regie,132 C. Debenedetti,146 D. V. Dedovich,79 A. M. Deiana,42 M. Del Gaudio,41b,41a J. Del Peso,98
46
132
145
7
69 69b
54
36 ove,132 F. Deliot,145 C. M. Delitzsch,7 M. Della Pietra,69a,69b D. Della Volpe,54 A. Dell’Acqua,36 Y. Delabat Diaz,
D. Delgove,
F. Deliot,
C. M. Delitzsch, M. Della Pietra,
,
D. Della Volpe,
A. Dell Acqua,
L. Dell’Asta,73a,73b M. Delmastro,5 C. Delporte,132 P. A. Delsart,58 D. A. DeMarco,167 S. Demers,183 M. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … A y
j
O. Bessidskaia Bylund,182 N. Besson,145 A. Bethani,100 S. Bethke,115 A. Betti,24 A. J. Bevan,92 J. Beyer,115 R. Bi,139 R. M. Bianchi,139 O. Biebel,114 D. Biedermann,19 R. Bielski,36 K. Bierwagen,99 N. V. Bies T. R. V. Billoud,109 M. Bindi,53 A. Bingul,12d C. Bini,72a,72b S. Biondi,23b,23a M. Birman,180 T. Bisanz,53 J. P. Biswal,161
100
48
134
25
28
46
26
57 A. Bitadze,100 C. Bittrich,48 K. Bjørke,134 K. M. Black,25 T. Blazek,28a I. Bloch,46 C. Blocker,26 A. Blue,57
U. Blumenschein,92 G. J. Bobbink,120 V. S. Bobrovnikov,122b,122a S. S. Bocchetta,96 A. Bocci,49 D. Boerner,46 D. Bogavac,14 A. Bitadze,
C. Bittrich,
K. Bjørke,
K. M. Black,
T. Blazek,
I. Bloch,
C. Blocker,
A. Blue,
U. Blumenschein,92 G. J. Bobbink,120 V. S. Bobrovnikov,122b,122a S. S. Bocchetta,96 A. Bocci,49 D. Boerner,46 D. Bogavac,14
122b 122
45
93
53 172
83
113
61b g
y
M. Bomben,136 M. Bona,92 J. S. Bonilla,131 M. Boonekamp,145 H. M. Borecka-Bielska,90 A. Borisov,123 G. Borissov,89
J. Bortfeldt,36 D. Bortoletto,135 V. Bortolotto,73a,73b D. Boscherini,23b M. Bosman,14 J. D. Bossio Sola,103 K. Bouaouda,35a 032007-23 032007-23 PHYS. REV. D 100, 032007 (2019) G. AAD et al. ,
,
g ,
,
y
,
,
,
D. Caforio,56 H. Cai,173 V. M. M. Cairo,153 O. Cakir,4a N. Calace,36 P. Calafiura,18 A. Calandri,101 G. Calderini,136
P. Calfayan,65 G. Callea,57 L. P. Caloba,80b S. Calvente Lopez,98 D. Calvet,38 S. Calvet,38 T. P. Calvet,155 M. Calvetti,71a,71b D. Caforio,
H. Cai,
V. M. M. Cairo,
O. Cakir,
N. Calace,
P. Calafiura,
A. Calandri,
G. Calderini,
P. Calfayan,65 G. Callea,57 L. P. Caloba,80b S. Calvente Lopez,98 D. Calvet,38 S. Calvet,38 T. P. Calvet,155 M. Calvetti,71a,71b P. Calfayan,65 G. Callea,57 L. P. Caloba,80b S. Calvente Lopez,98 D. Calvet,38 S. Calvet,38 T. P. Calvet,155 M. Calvetti,71a,71b R. Camacho Toro,136 S. Camarda,36 D. Camarero Munoz,98 P. Camarri,73a,73b D. Cameron,134 R. Caminal Armadans,102
C. Camincher,36 S. Campana,36 M. Campanelli,94 A. Camplani,40 A. Campoverde,151 V. Canale,69a,69b A. Canesse,103 M. Cano Bret,60c J. Cantero,129 T. Cao,161 Y. Cao,173 M. D. M. Capeans Garrido,36 M. Capua,41b,41a R. Cardarelli,73a
F. C. Cardillo,149 I. Carli,143 T. Carli,36 G. Carlino,69a B. T. Carlson,139 L. Carminati,68a,68b R. M. D. Carney,45a,45b
S. Caron,119 E. Carquin,147b S. Carrá,68a,68b J. W. S. Carter,167 M. P. Casado,14,k A. F. Casha,167 D. W. Casper,171 M. Cano Bret,
J. Cantero,
T. Cao,
Y. Cao,
M. D. M. Capeans Garrido,
M. Capua,
R. Cardarelli,
F. C. Cardillo,149 I. Carli,143 T. Carli,36 G. Carlino,69a B. T. J. Boudreau,139 E. V. Bouhova-Thacker,89 D. Boumediene,38 S. K. Boutle,57 A. Boveia,126 J. Boyd,36 D. Boye,33b,j
I. R. Boyko,79 A. J. Bozson,93 J. Bracinik,21 N. Brahimi,101 G. Brandt,182 O. Brandt,61a F. Braren,46 B. Brau,102 J. E. Brau,131
W. D. Breaden Madden,57 K. Brendlinger,46 L. Brenner,46 R. Brenner,172 S. Bressler,180 B. Brickwedde,99 D. L. Briglin,21
D. Britton,57 D. Britzger,115 I. Brock,24 R. Brock,106 G. Brooijmans,39 W. K. Brooks,147b E. Brost,121 J. H Broughton,21
P. A. Bruckman de Renstrom,84 D. Bruncko,28b A. Bruni,23b G. Bruni,23b L. S. Bruni,120 S. Bruno,73a,73b B. H. Brunt,32
M. Bruschi,23b N. Bruscino,139 P. Bryant,37 L. Bryngemark,96 T. Buanes,17 Q. Buat,36 P. Buchholz,151 A. G. Buckley,57
I. A. Budagov,79 M. K. Bugge,134 F. Bührer,52 O. Bulekov,112 T. J. Burch,121 S. Burdin,90 C. D. Burgard,120 A. M. Burger,129 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Carlson,139 L. Carminati,68a,68b R. M. D. Carney,45a,45b
S C
119 E C
i
147b S C
á 68a,68b J W S C t
167 M P C
d
14,k A F C
h
167 D W C
171 R. Castelijn,120 F. L. Castillo,174 V. Castillo Gimenez,174 N. F. Castro,140a,140e A R. Castelijn,120 F. L. Castillo,174 V. Castillo Gimenez,174 N. F. Castro,140a,140e A. Catinaccio,36 J. R. Catmore,134 A. Cattai,36
24
29
14
68
14
1
1b
12b J. Caudron,24 V. Cavaliere,29 E. Cavallaro,14 D. Cavalli,68a M. Cavalli-Sforza,14 V. Cavasinni,71a,71b E. Celebi,12b
F. Ceradini,74a,74b L. Cerda Alberich,174 A. S. Cerqueira,80a A. Cerri,156 L. Cerrito,73a,73b F. Cerutti,18 A. Cervelli,23b,23a J. Caudron,
V. Cavaliere,
E. Cavallaro,
D. Cavalli,
M. Cavalli Sforza,
V. Cavasinni,
E. Celebi,
F. Ceradini,74a,74b L. Cerda Alberich,174 A. S. Cerqueira,80a A. Cerri,156 L. Cerrito,73a,73b F. Cerutti,18 A. Cervelli,23b,23a S. A. Cetin,12b D. Chakraborty,121 S. K. Chan,59 W. S. Chan,120 W. Y. Chan,90 J. D. Chapman,32 B. Chargeishvili,159b
D. G. Charlton,21 T. P. Charman,92 C. C. Chau,34 S. Che,126 A. Chegwidden,106 S. Chekanov,6 S. V. Chekulaev,168a
G. A. Chelkov,79,l M. A. Chelstowska,36 B. Chen,78 C. Chen,60a C. H. Chen,78 H. Chen,29 J. Chen,60a J. Chen,39 S. Chen,137 y
p
g
D. G. Charlton,21 T. P. Charman,92 C. C. Chau,34 S. Che,126 A. Chegwidden,106 S. Chekanov,6 S. V. Chekulaev,168a
G A Chelkov 79,l M A Chelstowska 36 B Chen 78 C Chen 60a C H Chen 78 H Chen 29 J Chen 60a J Chen 39 S Chen 137 S. J. Chen,15c X. Chen,15b,m Y. Chen,82 Y-H. Chen,46 H. C. Cheng,63a H. J. Cheng,15a,15d A. Cheplakov,79
E. Cheremushkina,123 R. Cherkaoui El Moursli,35e E. Cheu,7 K. Cheung,64 T. J. A. Cheval´erias,145 L. Chevalier,145 S. J. Chen,15c X. Chen,15b,m Y. Chen,82 Y-H. Chen,46 H. C. Cheng,63a H. J. Cheng,15a,15d A. Cheplakov,79
E Ch
hki
123 R Ch k
i El M
li 35e E Ch
7 K Ch
64 T J A Ch
l´ i
145 L Ch
li
145 g
V. Chiarella,51 G. Chiarelli,71a G. Chiodini,67a A. S. Chisholm,36,21 A. Chitan,27b I. Chiu,163 Y. H. Chiu,176 M. V. Chizhov,79 g
V. Chiarella,51 G. Chiarelli,71a G. Chiodini,67a A. S. Chisholm,36,21 A. Chitan,27b I. Chiu,163 Y. H. Chiu,176 M. V. Chizhov,79
K. Choi,65 A. R. Chomont,72a,72b S. Chouridou,162 Y. S. Chow,120 M. C. Chu,63a J. Chudoba,141 A. J. Chuinard,103 J. J. Chwastowski,84 L. Chytka,130 K. M. Ciesla,84 D. Cinca,47 V. Cindro,91 I. A. Cioară,27b A. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … j
y
y
y
g
G. Eigen,17 K. Einsweiler,18 T. Ekelof,172 M. El Kacimi,35c R. El Kosseifi,101 V. Ellajosyula,172 M. Ellert,172 F. Ellinghaus,182
A. A. Elliot,92 N. Ellis,36 J. Elmsheuser,29 M. Elsing,36 D. Emeliyanov,144 A. Emerman,39 Y. Enari,163 J. S. Ennis,178 g
y
M. B. Epland,49 J. Erdmann,47 A. Ereditato,20 M. Errenst,36 M. Escalier,132 C. Escobar,174 O. Estrada Pastor,174 E. Etzion,161 ,47 A. Ereditato,20 M. Errenst,36 M. Escalier,132 C. Escobar,174 O. Estrada Pastor,174 E. Etzion,161 M. B. Epland,49 J. Erdmann,47 A. Ereditato,20 M. Errenst,36 M. Escalier,132 C. Escobar,174 O. Est 8 F. Fabbri,57 L. Fabbri,23b,23a V. Fabiani,119 G. Facini,94 R. M. Faisca Rodrigues Pereira,140a H. Evans,
A. Ezhilov,
F. Fabbri,
L. Fabbri,
V. Fabiani,
G. Facini,
R. M. Faisca Rodrigues Pereira,
R. M. Fakhrutdinov,123 S. Falciano,72a P. J. Falke,5 S. Falke,5 J. Faltova,143 Y. Fang,15a Y. Fang,15a G. Fanourakis,44 . Falciano,72a P. J. Falke,5 S. Falke,5 J. Faltova,143 Y. Fang,15a Y. Fang,15a G. Fanourakis,44 A. Farilla,74a E. M. Farina,70a,70b T. Farooque,106 S. Farrell,18 S. M. Farrington,178 P. Farthouat,36 ,68a,68b A. Farbin,8 A. Farilla,74a E. M. Farina,70a,70b T. Farooque,106 S. Farrell,18 S. M. Farrington
35
36
9
50
32
132 F. Fassi,35e P. Fassnacht,36 D. Fassouliotis,9 M. Faucci Giannelli,50 W. J. Fawcett,32 L. Fayard,132 O. L. Fedin,138,q kert,42 S. Feigl,134 L. Feligioni,101 A. Fell,149 C. Feng,60b E. J. Feng,36 M. Feng,49 M. J. Fenton W. Fedorko,175 M. Feickert,42 S. Feigl,134 L. Feligioni,101 A. Fell,149 C. Feng,60b E. J. Feng,36 W. Fedorko,
M. Feickert,
S. Feigl,
L. Feligioni,
A. Fell,
C. Feng,
E. J. Feng,
M. Feng,
M. J. Fenton,
A. B. Fenyuk,123 J. Ferrando,46 A. Ferrante,173 A. Ferrari,172 P. Ferrari,120 R. Ferrari,70a D. E. Ferreira de Lima,61b A. B. Fenyuk,123 J. Ferrando,46 A. Ferrante,173 A. Ferrari,172 P. Ferrari,120 R. Ferrari,70a D. E. Ferreira de Lima,61b y
A. Ferrer,174 D. Ferrere,54 C. Ferretti,105 F. Fiedler,99 A. Filipčič,91 F. Filthaut,119 K. D. Fine ,54 C. Ferretti,105 F. Fiedler,99 A. Filipčič,91 F. Filthaut,119 K. D. Finelli,25 M. C. N. Fiolhais,14 p
L. Fiorini,174 F. Fischer,114 W. C. Fisher,106 I. Fleck,151 P. Fleischmann,105 R. R. M. Fletcher,137 T. Flick,182 B. M. Flierl,114 L. F. Flores,137 L. R. Flores Castillo,63a F. M. Follega,75a,75b N. Fomin,17 G. T. Forcolin,75a,75b A. Formica,145 F. A. Förster,14
A. C. Forti,100 A. G. Foster,21 M. G. Foti,135 D. Fournier,132 H. Fox,89 P. Francavilla,71a,71b S. Francescato,72a,72b L. F. Flores,137 L. R. Flores Castillo,63a F. M. Follega,75a,75b N. Fomin,17 G. T. Forcolin,75a,75b A. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Demichev,79 ,
g
,
,
,
,
p ,
q
,
L. Dell’Asta,73a,73b M. Delmastro,5 C. Delporte,132 P. A. Delsart,58 D. A. DeMarco,167 S. Demers,183 M. Demichev,79 p
ntigny,109 S. P. Denisov,123 D. Denysiuk,120 L. D’Eramo,136 D. Derendarz,84 J. E. Derkaoui,35d p
Denisov,123 D. Denysiuk,120 L. D’Eramo,136 D. Derendarz,84 J. E. Derkaoui,35d F. Derue,136 P. Dervan,90 K. Desch,24 C. Deterre,46 K. Dette,167 C. Deutsch,24 M. R. Devesa,30 P. O. Deviveiros,36 A. Dewhurst,144
S. Dhaliwal,26 F. A. Di Bello,54 A. Di Ciaccio,73a,73b L. Di Ciaccio,5 W. K. Di Clemente,137 C. Di Donato,69a,69b
A. Di Girolamo,36 G. Di Gregorio,71a,71b B. Di Micco,74a,74b R. Di Nardo,102 K. F. Di Petrillo,59 R. Di Sipio,167 S. Dhaliwal,26 F. A. Di Bello,54 A. Di Ciaccio,73a,73b L. Di Ciaccio,5 W. K. Di Clemente,137 C. Di Donato,69a,69b
A. Di Girolamo,36 G. Di Gregorio,71a,71b B. Di Micco,74a,74b R. Di Nardo,102 K. F. Di Petrillo,59 R. Di Sipio,167
D. Di Valentino,34 C. Diaconu,101 F. A. Dias,40 T. Dias Do Vale,140a M. A. Diaz,147a J. Dickinson,18 E. B. Diehl,105 A. Di Girolamo,36 G. Di Gregorio,71a,71b B. Di Micco,74a,74b R. Di Nardo,102 K. F. Di Petrillo,59 R. Di Sipio,167
D. Di Valentino,34 C. Diaconu,101 F. A. Dias,40 T. Dias Do Vale,140a M. A. Diaz,147a J. Dickinson,18 E. B. Diehl,105 032007-24 032007-24 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … PHYS. REV. D 100, 032007 (2019) SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Formica,145 F. A. Förster,14
A. C. Forti,100 A. G. Foster,21 M. G. Foti,135 D. Fournier,132 H. Fox,89 P. Francavilla,71a,71b S. Francescato,72a,72b
M. Franchini,23b,23a S. Franchino,61a D. Francis,36 L. Franconi,20 M. Franklin,59 A. N. Fray,92 B. Freund,109 W. S. Freund,80b M. Franchini,23b,23a S. Franchino,61a D. Francis,36 L. Franconi,20 M. Franklin,59 A. N. Fray,92 B. Freund,109 W. S. Freund,80b
E. M. Freundlich,47 D. C. Frizzell,128 D. Froidevaux,36 J. A. Frost,135 C. Fukunaga,164 E. Fullana Torregrosa,174 M. Franchini,
S. Franchino,
D. Francis,
L. Franconi,
M. Franklin,
A. N. Fray,
B. Freund,
W. S. Freund,
E. M. Freundlich,47 D. C. Frizzell,128 D. Froidevaux,36 J. A. Frost,135 C. Fukunaga,164 E. Fullana Torregrosa,174
55b 55
116
174
23b 23
18
83
54
115 E. M. Freundlich,47 D. C. Frizzell,128 D. Froidevaux,36 J. A. Frost,135 C. Fukunaga,164 E. Fullana Torregrosa,174
E. Fumagalli,55b,55a T. Fusayasu,116 J. Fuster,174 A. Gabrielli,23b,23a A. Gabrielli,18 G. P. Gach,83a S. Gadatsch,54 P. Gadow,115 E. Fumagalli,55b,55a T. Fusayasu,116 J. Fuster,174 A. Gabrielli,23b,23a A. Gabrielli,18 G. P. Gach,83a S. Gadatsch,54 P. Gadow,115
G. Gagliardi,55b,55a L. G. Gagnon,109 C. Galea,27b B. Galhardo,140a G. E. Gallardo,135 E. J. Gallas,135 B. J. Gallop,144 E. Fumagalli,55b,55a T. Fusayasu,116 J. Fuster,174 A. Gabrielli,23b,23a A. Gabrielli,18 G. P. Gach,83a S. Gadatsch,54 P. Gadow,115
G. Gagliardi,55b,55a L. G. Gagnon,109 C. Galea,27b B. Galhardo,140a G. E. Gallardo,135 E. J. Gallas,135 B. J. Gallop,144
P. Gallus,142 G. Galster,40 R. Gamboa Goni,92 K. K. Gan,126 S. Ganguly,180 J. Gao,60a Y. Gao,90 Y. S. Gao,31,h C. García,174 g
,
y
,
,
,
,
,
,
,
G. Gagliardi,55b,55a L. G. Gagnon,109 C. Galea,27b B. Galhardo,140a G. E. Gallardo,135 E. J. Gallas,135 B. J. Gallop,144
P Gallus 142 G Galster 40 R Gamboa Goni 92 K K Gan 126 S Ganguly 180 J Gao 60a Y Gao 90 Y S Gao 31,h C García 174 g
y
G. Gagliardi,55b,55a L. G. Gagnon,109 C. Galea,27b B. Galhardo,140a G. E. Gallardo,135 E. J. Gallas,135 B. J. Gallop,144 g
p
. Gamboa Goni,92 K. K. Gan,126 S. Ganguly,180 J. Gao,60a Y. Gao,90 Y. S. Gao,31,h C. García,174 2 G. Galster,40 R. Gamboa Goni,92 K. K. Gan,126 S. Ganguly,180 J. Gao,60a Y. Gao,90 Y. S. Gao,31 J. E. García Navarro,174 J. A. García Pascual,15a C. Garcia-Argos,52 M. Garcia-Sciveres,18 R. W. Gardner,37 N. Garelli,153
S. Gargiulo,52 V. Garonne,134 A. Gaudiello,55b,55a G. Gaudio,70a I. L. Gavrilenko,110 A. Gavrilyuk,111 C. Gay,175
24
10
27b
144
53
99
61a
55b J. E. J. Dietrich,19 S. Díez Cornell,46 A. Dimitrievska,18 W. Ding,15b J. Dingfelder,24 F. Dittus,36 F. Djama,101 T. Djobava,159b
J. I. Djuvsland,17 M. A. B. Do Vale,80c M. Dobre,27b D. Dodsworth,26 C. Doglioni,96 J. Dolejsi,143 Z. Dolezal,143
M. Donadelli,80d J. Donini,38 A. D’onofrio,92 M. D’Onofrio,90 J. Dopke,144 A. Doria,69a M. T. Dova,88 A. T. Doyle,57
E. Drechsler,152 E. Dreyer,152 T. Dreyer,53 A. S. Drobac,170 Y. Duan,60b F. Dubinin,110 M. Dubovsky,28a A. Dubreuil,54
E. Duchovni,180 G. Duckeck,114 A. Ducourthial,136 O. A. Ducu,109 D. Duda,115 A. Dudarev,36 A. C. Dudder,99
E. M. Duffield,18 L. Duflot,132 M. Dührssen,36 C. Dülsen,182 M. Dumancic,180 A. E. Dumitriu,27b A. K. Duncan,57
M. Dunford,61a A. Duperrin,101 H. Duran Yildiz,4a M. Düren,56 A. Durglishvili,159b D. Duschinger,48 B. Dutta,46
D. Duvnjak,1 G. I. Dyckes,137 M. Dyndal,36 S. Dysch,100 B. S. Dziedzic,84 K. M. Ecker,115 R. C. Edgar,105 T. Eifert,36
G. Eigen,17 K. Einsweiler,18 T. Ekelof,172 M. El Kacimi,35c R. El Kosseifi,101 V. Ellajosyula,172 M. Ellert,172 F. Ellinghaus,182
A. A. Elliot,92 N. Ellis,36 J. Elmsheuser,29 M. Elsing,36 D. Emeliyanov,144 A. Emerman,39 Y. Enari,163 J. S. Ennis,178
M B Epland 49 J Erdmann 47 A Ereditato 20 M Errenst 36 M Escalier 132 C Escobar 174 O Estrada Pastor 174 E Et ion 161 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … García Navarro,
J. A. García Pascual,
C. Garcia-Argos,
M. Garcia-Sciveres,
R. W. Gardner,
N. Garelli,
S. Gargiulo,52 V. Garonne,134 A. Gaudiello,55b,55a G. Gaudio,70a I. L. Gavrilenko,110 A. Gavrilyuk,111 C. Gay,175
G. Gaycken,24 E. N. Gazis,10 A. A. Geanta,27b C. N. P. Gee,144 J. Geisen,53 M. Geisen,99 M. P. Geisler,61a C. Gemme,55b
M. H. Genest,58 C. Geng,105 S. Gentile,72a,72b S. George,93 T. Geralis,44 D. Gerbaudo,14 L. O. Gerlach,53 S. Gargiulo,
V. Garonne,
A. Gaudiello,
G. Gaudio,
I. L. Gavrilenko,
A. Gavrilyuk,
C. Gay,
G. Gaycken,24 E. N. Gazis,10 A. A. Geanta,27b C. N. P. Gee,144 J. Geisen,53 M. Geisen,99 M. P. Geisler,61a C. Gemme,55b
M. H. Genest,58 C. Geng,105 S. Gentile,72a,72b S. George,93 T. Geralis,44 D. Gerbaudo,14 L. O. Gerlach,53 G. Gaycken,
E. N. Gazis,
A. A. Geanta,
C. N. P. Gee,
J. Geisen,
M. Geisen,
M. P. Geisler,
C. Gemme,
M. H. Genest,58 C. Geng,105 S. Gentile,72a,72b S. George,93 T. Geralis,44 D. Gerbaudo,14 L. O. Gerlach,53
P. Gessinger-Befurt,99 G. Gessner,47 S. Ghasemi,151 M. Ghasemi Bostanabad,176 M. Ghneimat,24 A. Ghosh,77
B. Giacobbe,23b S. Giagu,72a,72b N. Giangiacomi,23b,23a P. Giannetti,71a A. Giannini,69a,69b S. M. Gibson,93 M. Gignac,146 P. Gessinger-Befurt,99 G. Gessner,47 S. Ghasemi,151 M. Ghasemi Bostanabad,176 M. Ghneimat,24 A. Ghosh,77
B. Giacobbe,23b S. Giagu,72a,72b N. Giangiacomi,23b,23a P. Giannetti,71a A. Giannini,69a,69b S. M. Gibson,93 M. Gignac,146 D. Gillberg,34 G. Gilles,182 D. M. Gingrich,3,e M. P. Giordani,66a,66c F. M. Giorgi,23b P. F. Giraud,145 G. Giugliarelli,66a,66c
68
73 73b
162
9
14
10
113 D. Giugni,68a F. Giuli,73a,73b S. Gkaitatzis,162 I. Gkialas,9,r E. L. Gkougkousis,14 P. Gkountoumis,10 L. K. Gladilin,113
C. Glasman,98 J. Glatzer,14 P. C. F. Glaysher,46 A. Glazov,46 M. Goblirsch-Kolb,26 S. Goldfarb,104 T. Golling,54
D. Golubkov,123 A. Gomes,140a,140b R. Goncalves Gama,53 R. Gonçalo,140a,140b G. Gonella,52 L. Gonella,21 A. Gongadze,79 F. Gonnella,21 J. L. Gonski,59 S. González de la Hoz,174 S. Gonzalez-Sevilla,54 G. R. Gonzalvo Rodriguez,174 L. Goossens,36
P. A. Gorbounov,111 H. A. Gordon,29 B. Gorini,36 E. Gorini,67a,67b A. Gorišek,91 A. T. Goshaw,49 M. I. Gostkin,79
C. A. Gottardo,24 M. Gouighri,35b D. Goujdami,35c A. G. Goussiou,148 N. Govender,33b,s C. Goy,5 E. Gozani,160 ,
,
,
,
g
,
,
P. A. Gorbounov,111 H. A. Gordon,29 B. Gorini,36 E. Gorini,67a,67b A. Gorišek,91 A. T. Goshaw,49 M. I. Gostkin,79
C. A. Gottardo,24 M. Gouighri,35b D. Goujdami,35c A. G. Goussiou,148 N. Govender,33b,s C. Goy,5 E. Gozani,160 g
j
y
I. Grabowska-Bold,83a E. C. Graham,90 J. Gramling,171 E. Gramstad,134 S. Grancagnolo,19 M. Grandi,156 V. Gratchev,138 I. Grabowska-Bold,83a E. C. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Graham,90 J. Gramling,171 E. Gramstad,134 S. Grancagnolo,19 M. Grandi,156 V. Gratchev,138
P M Gravila 27f F G Gravili 67a,67b C Gray 57 H M Gray 18 C Grefe 24 K Gregersen 96 I M Gregor 46 P Grenier 153 P. M. Gravila,27f F. G. Gravili,67a,67b C. Gray,57 H. M. Gray,18 C. Grefe,24 K. Gregersen,96 I. M. Gregor,46 P. Grenier,153
K. Grevtsov,46 N. A. Grieser,128 J. Griffiths,8 A. A. Grillo,146 K. Grimm,31,t S. Grinstein,14,u J.-F. Grivaz,132 S. Groh,99
E. Gross,180 J. Grosse-Knetter,53 Z. J. Grout,94 C. Grud,105 A. Grummer,118 L. Guan,105 W. Guan,181 J. Guenther,36
A. Guerguichon,132 F. Guescini,168a D. Guest,171 R. Gugel,52 B. Gui,126 T. Guillemin,5 S. Guindon,36 U. Gul,57 J. Guo,60c
W. Guo,105 Y. Guo,60a,v Z. Guo,101 R. Gupta,46 S. Gurbuz,12c G. Gustavino,128 P. Gutierrez,128 C. Gutschow,94 C. Guyot,145
M. P. Guzik,83a C. Gwenlan,135 C. B. Gwilliam,90 A. Haas,124 C. Haber,18 H. K. Hadavand,8 N. Haddad,35e A. Hadef,60a
S. Hageböck,36 M. Hagihara,169 M. Haleem,177 J. Haley,129 G. Halladjian,106 G. D. Hallewell,101 K. Hamacher,182
P. Hamal,130 K. Hamano,176 H. Hamdaoui,35e G. N. Hamity,149 K. Han,60a,w L. Han,60a S. Han,15a,15d K. Hanagaki,81,x
M. Hance,146 D. M. Handl,114 B. Haney,137 R. Hankache,136 E. Hansen,96 J. B. Hansen,40 J. D. Hansen,40 M. C. Hansen,24 P. M. Gravila,27f F. G. Gravili,67a,67b C. Gray,57 H. M. Gray,18 C. Grefe,24 K. Gregersen,96 I. M. Gregor,46 P. Grenier,153
K. Grevtsov,46 N. A. Grieser,128 J. Griffiths,8 A. A. Grillo,146 K. Grimm,31,t S. Grinstein,14,u J.-F. Grivaz,132 S. Groh,99
E. Gross,180 J. Grosse-Knetter,53 Z. J. Grout,94 C. Grud,105 A. Grummer,118 L. Guan,105 W. Guan,181 J. Guenther,36
A. Guerguichon,132 F. Guescini,168a D. Guest,171 R. Gugel,52 B. Gui,126 T. Guillemin,5 S. Guindon,36 U. Gul,57 J. Guo,60c K. Grevtsov,
N. A. Grieser,
J. Griffiths, A. A. Grillo,
K. Grimm,
, S. Grinstein,
, J.-F. Grivaz,
S. Groh,
E. Gross,180 J. Grosse-Knetter,53 Z. J. Grout,94 C. Grud,105 A. Grummer,118 L. Guan,105 W. Guan,181 J. Guenther,36
A. Guerguichon,132 F. Guescini,168a D. Guest,171 R. Gugel,52 B. Gui,126 T. Guillemin,5 S. Guindon,36 U. Gul,57 J. Guo,60c
W G
105 Y G
60a v Z G
101 R G
46 S G
b
12c G G
i
128 P G i
128 C G
h
94 C G
145 M. P. Guzik,83a C. Gwenlan,135 C. B. Gwilliam,90 A. Haas,124 C. Haber,18 H. K. Hadavand,8 N. Haddad,35e A. Hadef,60a
S. Hageböck,36 M. Hagihara,169 M. Haleem,177 J. Haley,129 G. Halladjian,106 G. D. Hallewell,101 K. Hamacher,182 032007-25 032007-25 PHYS. REV. P. H. Hansen,40 E. C. Hanson,100 K. Hara,169 A. S. Hard,181 T. Harenberg,182 S. Harkusha,107 P. F. Harrison,178
N. M. Hartmann,114 Y. Hasegawa,150 A. Hasib,50 S. Hassani,145 S. Haug,20 R. Hauser,106 L. B. Havener,39 M. Havranek,142
C. M. Hawkes,21 R. J. Hawkings,36 D. Hayden,106 C. Hayes,155 R. L. Hayes,175 C. P. Hays,135 J. M. Hays,92 H. S. Hayward,90
S. J. Haywood,144 F. He,60a M. P. Heath,50 V. Hedberg,96 L. Heelan,8 S. Heer,24 K. K. Heidegger,52 J. Heilman,34 S. Heim,46
T. Heim,18 B. Heinemann,46,y J. J. Heinrich,131 L. Heinrich,36 C. Heinz,56 J. Hejbal,141 L. Helary,61b A. Held,175
S. Hellesund,134 C. M. Helling,146 S. Hellman,45a,45b C. Helsens,36 R. C. W. Henderson,89 Y. Heng,181 S. Henkelmann,175
A. M. Henriques Correia,36 G. H. Herbert,19 H. Herde,26 V. Herget,177 Y. Hernández Jim´enez,33c H. Herr,99
M. G. Herrmann,114 T. Herrmann,48 G. Herten,52 R. Hertenberger,114 L. Hervas,36 T. C. Herwig,137 G. G. Hesketh,94
N. P. Hessey,168a A. Higashida,163 S. Higashino,81 E. Higón-Rodriguez,174 K. Hildebrand,37 E. Hill,176 J. C. Hill,32
K. K. Hill,29 K. H. Hiller,46 S. J. Hillier,21 M. Hils,48 I. Hinchliffe,18 F. Hinterkeuser,24 M. Hirose,133 S. Hirose,52
D. Hirschbuehl,182 B. Hiti,91 O. Hladik,141 D. R. Hlaluku,33c X. Hoad,50 J. Hobbs,155 N. Hod,180 M. C. Hodgkinson,149
A. Hoecker,36 F. Hoenig,114 D. Hohn,52 D. Hohov,132 T. R. Holmes,37 M. Holzbock,114 L. B. A. H Hommels,32 S. Honda,169
T. Honda,81 T. M. Hong,139 A. Hönle,115 B. H. Hooberman,173 W. H. Hopkins,6 Y. Horii,117 P. Horn,48 A. J. Horton,152
L. A. Horyn,37 J-Y. Hostachy,58 A. Hostiuc,148 S. Hou,158 A. Hoummada,35a J. Howarth,100 J. Hoya,88 M. Hrabovsky,130
J. Hrdinka,76 I. Hristova,19 J. Hrivnac,132 A. Hrynevich,108 T. Hryn’ova,5 P. J. Hsu,64 S.-C. Hsu,148 Q. Hu,29 S. Hu,60c
Y. Huang,15a Z. Hubacek,142 F. Hubaut,101 M. Huebner,24 F. Huegging,24 T. B. Huffman,135 M. Huhtinen,36 R. F. H. Hunter,34
P. Huo,155 A. M. Hupe,34 N. Huseynov,79,z J. Huston,106 J. Huth,59 R. Hyneman,105 S. Hyrych,28a G. Iacobucci,54
G. Iakovidis,29 I. Ibragimov,151 L. Iconomidou-Fayard,132 Z. Idrissi,35e P. I. Iengo,36 R. Ignazzi,40 O. Igonkina,120,a,aa
R. Iguchi,163 T. Iizawa,54 Y. Ikegami,81 M. Ikeno,81 D. Iliadis,162 N. Ilic,119 F. Iltzsche,48 G. Introzzi,70a,70b M. Iodice,74a
K. Iordanidou,39 V. Ippolito,72a,72b M. F. Isacson,172 N. Ishijima,133 M. Ishino,163 M. Ishitsuka,165 W. Islam,129 C. Issever,135
S. Istin,160 F. Ito,169 J. M. Iturbe Ponce,63a R. Iuppa,75a,75b A. Ivina,180 H. Iwasaki,81 J. M. Izen,43 V. Izzo,69a P. Jacka,141
P. Jackson,1 R. M. Jacobs,24 V. Jain,2 G. Jäkel,182 K. B. Jakobi,99 K. Jakobs,52 S. Jakobsen,76 T. Jakoubek,141 J. Jamieson,57
K. W. Janas,83a R. Jansky,54 J. Janssen,24 M. Janus,53 P. A. Janus,83a G. Jarlskog,96 N. Javadov,79,z T. Javůrek,36
M. Javurkova,52 F. Jeanneau,145 L. Jeanty,131 J. Jejelava,159a,bb A. Jelinskas,178 P. Jenni,52,cc J. Jeong,46 N. Jeong,46
S. J´ez´equel,5 H. Ji,181 J. Jia,155 H. Jiang,78 Y. Jiang,60a Z. Jiang,153,dd S. Jiggins,52 F. A. Jimenez Morales,38
J. Jimenez Pena,174 S. Jin,15c A. Jinaru,27b O. Jinnouchi,165 H. Jivan,33c P. Johansson,149 K. A. Johns,7 C. A. Johnson,65
K. Jon-And,45a,45b R. W. L. Jones,89 S. D. Jones,156 S. Jones,7 T. J. Jones,90 J. Jongmanns,61a P. M. Jorge,140a J. Jovicevic,36
X. Ju,18 J. J. Junggeburth,115 A. Juste Rozas,14,u A. Kaczmarska,84 M. Kado,72a,72b H. Kagan,126 M. Kagan,153 C. Kahra,99
179
160
96
99
123
91
163 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … D 100, 032007 (2019) G. AAD et al. T. Honda,81 T. M. Hong,139 A. Hönle,115 B. H. Hooberman,173 W. H. Hopkins,6 Y. Horii,117 P. Horn,48 A. J. Horton,152
5
5
5 J. Hrdinka,76 I. Hristova,19 J. Hrivnac,132 A. Hrynevich,108 T. Hryn’ova,5 P. J. Hsu,64 S.-C. Hsu,148 Q. Hu,29 S. Hu,60c
5
5
6 Y. Huang,15a Z. Hubacek,142 F. Hubaut,101 M. Huebner,24 F. Huegging,24 T. B. Huffman,135 M. Huhtinen,36 R. F. H. Hunter,34
P. Huo,155 A. M. Hupe,34 N. Huseynov,79,z J. Huston,106 J. Huth,59 R. Hyneman,105 S. Hyrych,28a G. Iacobucci,54
G. Iakovidis,29 I. Ibragimov,151 L. Iconomidou-Fayard,132 Z. Idrissi,35e P. I. Iengo,36 R. Ignazzi,40 O. Igonkina,120,a,aa
R. Iguchi,163 T. Iizawa,54 Y. Ikegami,81 M. Ikeno,81 D. Iliadis,162 N. Ilic,119 F. Iltzsche,48 G. Introzzi,70a,70b M. Iodice,74a
39
72 72b
172
133
163
165
129
135 G. Iakovidis,29 I. Ibragimov,151 L. Iconomidou-Fayard,132 Z. Idrissi,35e P. I. Iengo,36 R. Ignazzi,40 O. Igonkina,120,a,aa
R. Iguchi,163 T. Iizawa,54 Y. Ikegami,81 M. Ikeno,81 D. Iliadis,162 N. Ilic,119 F. Iltzsche,48 G. Introzzi,70a,70b M. Iodice,74a R. Iguchi,163 T. Iizawa,54 Y. Ikegami,81 M. Ikeno,81 D. Iliadis,162 N. Ilic,119 F. Iltzsche,48 G. Introzzi,70a,70b M. Iodice,74a pp
j
S. Istin,160 F. Ito,169 J. M. Iturbe Ponce,63a R. Iuppa,75a,75b A. Ivina,180 H. Iwasaki,81 J. M. Izen,43 V. Izzo,69a P. Jacka,141
1
24
2
182
99
52
76
141
57 P. Jackson,1 R. M. Jacobs,24 V. Jain,2 G. Jäkel,182 K. B. Jakobi,99 K. Jakobs,52 S. Jakobsen,76 T. Jakoubek,141 J. Jamieson,57
K. W. Janas,83a R. Jansky,54 J. Janssen,24 M. Janus,53 P. A. Janus,83a G. Jarlskog,96 N. Javadov,79,z T. Javůrek,36
M. Javurkova,52 F. Jeanneau,145 L. Jeanty,131 J. Jejelava,159a,bb A. Jelinskas,178 P. Jenni,52,cc J. Jeong,46 N. Jeong,46
S. J´ez´equel,5 H. Ji,181 J. Jia,155 H. Jiang,78 Y. Jiang,60a Z. Jiang,153,dd S. Jiggins,52 F. A. Jimenez Morales,38 J. Jimenez Pena,174 S. Jin,15c A. Jinaru,27b O. Jinnouchi,165 H. Jivan,33c P. Johansson,149 K K. Jon-And,45a,45b R. W. L. Jones,89 S. D. Jones,156 S. Jones,7 T. J. Jones,90 J. Jongmanns,61a P. M. Jorge,140a J. Jovicevic,36 K. Jon-And,45a,45b R. W. L. Jones,89 S. D. Jones,156 S. Jones,7 T. J. Jones,90 J. Jongmanns,61a P. X. Ju,18 J. J. Junggeburth,115 A. Juste Rozas,14,u A. Kaczmarska,84 M. Kado,72a,72b H. Kagan,126 M. Kagan,153 C. Kahra,99
T. Kaji,179 E. Kajomovitz,160 C. W. Kalderon,96 A. Kaluza,99 A. Kamenshchikov,123 L. Kanjir,91 Y. Kano,163
V. A. Kantserov,112 J. Kanzaki,81 L. S. Kaplan,181 D. Kar,33c M. J. Kareem,168b E. Karentzos,10 S. N. Karpov,79
79
89
123
181
126
45 45b
163 X. Ju,18 J. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … J. Junggeburth,115 A. Juste Rozas,14,u A. Kaczmarska,84 M. Kado,72a,72b H. Kagan,126 M. Kagan,153 C. Kahra,99
T. Kaji,179 E. Kajomovitz,160 C. W. Kalderon,96 A. Kaluza,99 A. Kamenshchikov,123 L. Kanjir,91 Y. Kano,163
V. A. Kantserov,112 J. Kanzaki,81 L. S. Kaplan,181 D. Kar,33c M. J. Kareem,168b E. Karentzos,10 S. N. Karpov,79
Z. M. Karpova,79 V. Kartvelishvili,89 A. N. Karyukhin,123 L. Kashif,181 R. D. Kass,126 A. Kastanas,45a,45b Y. Kataoka,163
C. Kato,60d,60c J. Katzy,46 K. Kawade,82 K. Kawagoe,87 T. Kawaguchi,117 T. Kawamoto,163 G. Kawamura,53 E. F. Kay,176
122b 122
176
42
34
96
156
21
21 j
j
j
V. A. Kantserov,112 J. Kanzaki,81 L. S. Kaplan,181 D. Kar,33c M. J. Kareem,168b E. Karentzos,10 S. N. Karpov,79
Z. M. Karpova,79 V. Kartvelishvili,89 A. N. Karyukhin,123 L. Kashif,181 R. D. Kass,126 A. Kastanas,45a,45b Y. Kataoka,163
C. Kato,60d,60c J. Katzy,46 K. Kawade,82 K. Kawagoe,87 T. Kawaguchi,117 T. Kawamoto,163 G. Kawamura,53 E. F. Kay,176 ,
,
p
,
,
,
,
p
,
Z. M. Karpova,79 V. Kartvelishvili,89 A. N. Karyukhin,123 L. Kashif,181 R. D. Kass,126 A. Kastanas,45a,45b Y. Kataoka,163
C. Kato,60d,60c J. Katzy,46 K. Kawade,82 K. Kawagoe,87 T. Kawaguchi,117 T. Kawamoto,163 G. Kawamura,53 E. F. Kay,176 V. F. Kazanin,122b,122a R. Keeler,176 R. Kehoe,42 J. S. Keller,34 E. Kellermann,96 D. Kelsey,156 J. J. Kempster,21 J. Kendrick,21 D. Kobayashi,87 T. Kobayashi,163 M. Kobel,48 M. Kocian,153 P. Kodys,143 P. T. Koenig,24 T. Koffas,34 N. M. Köhler,115
T. Koi,153 M. Kolb,61b I. Koletsou,5 T. Komarek,130 T. Kondo,81 N. Kondrashova,60c K. Köneke,52 A. C. König,119 g
T. Kono,125 R. Konoplich,124,ee V. Konstantinides,94 N. Konstantinidis,94 B. Konya,96 R. Kopeliansky,65 S. Koperny,83a K. Korcyl,84 K. Kordas,162 G. Koren,161 A. Korn,94 I. Korolkov,14 E. V. Korolkova,149 N. Korotkova,113 O. Kortner,115
S. Kortner,115 T. Kosek,143 V. V. Kostyukhin,24 A. Kotwal,49 A. Koulouris,10 A. Kourkoumeli-Charalampidi,70a,70b
C. Kourkoumelis,9 E. Kourlitis,149 V. Kouskoura,29 A. B. Kowalewska,84 R. Kowalewski,176 C. Kozakai,163
W. Kozanecki,145 A. S. Kozhin,123 V. A. Kramarenko,113 G. Kramberger,91 D. Krasnopevtsev,60a M. W. Krasny,136
A. Krasznahorkay,36 D. Krauss,115 J. A. Kremer,83a J. Kretzschmar,90 P. Krieger,167 F. Krieter,114 A. Krishnan,61b
K. Krizka,18 K. Kroeninger,47 H. Kroha,115 J. Kroll,141 J. Kroll,137 J. Krstic,16 U. Kruchonak,79 H. Krüger,24 N. Krumnack,78
M. C. Kruse,49 T. Kubota,104 S. Kuday,4b J. T. Kuechler,46 S. Kuehn,36 A. Kugel,61a T. Kuhl,46 V. Kukhtin,79 R. Kukla,101 032007-26 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … PHYS. REV. D 100, 032007 (2019) SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … D. Lellouch,180,a K. J. C. Leney,42 T. Lenz,24 B. Lenzi,36 R. Leone,7 S. Leone,71a C. Leonidopoulos,50 A. Leopold,136
G. Lerner,156 C. Leroy,109 R. Les,167 C. G. Lester,32 M. Levchenko,138 J. Levêque,5 D. Levin,105 L. J. Levinson,180 G. Lerner,
C. Leroy,
R. Les,
C. G. Lester,
M. Levchenko,
J. Levêque, D. Levin,
L. J. Levinson,
D. J. Lewis,21 B. Li,15b B. Li,105 C-Q. Li,60a F. Li,60c H. Li,60a H. Li,60b J. Li,60c K. Li,153 L. Li,60c M. Li,15a Q. Li,15a,15d Q. Y. Li,60a S. Li,60d,60c X. Li,46 Y. Li,46 Z. Li,60b Z. Liang,15a B. Liberti,73a A. Liblong,167 K. Lie,63c S. Liem,120 C. Y. Lin,32
K. Lin,106 T. H. Lin,99 R. A. Linck,65 J. H. Lindon,21 A. L. Lionti,54 E. Lipeles,137 A. Lipniacka,17 M. Lisovyi,61b
173 hh
175
146
8
78 ii
6
29
105
60 K. Lin,106 T. H. Lin,99 R. A. Linck,65 J. H. Lindon,21 A. L. Lionti,54 E. Lipeles,137 A. Lipniacka,17 M. Lisovyi,61b
173 hh
175
146
8
78 ii
6
29
105
60 J. K. K. Liu,135 K. Liu,136 M. Liu,60a P. Liu,18 Y. Liu,15a,15d Y. L. Liu,105 Y. W. Liu,60a M. Livan,70a,70b A. Lleres,58 J. Llorente Merino,15a S. L. Lloyd,92 C. Y. Lo,63b F. Lo Sterzo,42 E. M. Lobodzinska,46 P. Loch,7 S. Loffredo,73a,73b
T. Lohse,19 K. Lohwasser,149 M. Lokajicek,141 J. D. Long,173 R. E. Long,89 L. Longo,36 K. A. Looper,126 J. A. Lopez,147b y
T. Lohse,19 K. Lohwasser,149 M. Lokajicek,141 J. D. Long,173 R. E. Long,89 L. Longo,36 K. A. Looper,126 J. A. Lopez,147b p
p
X. Lou,15a A. Lounis,132 J. Love,6 P. A. Love,89 J. J. Lozano Bahilo,174 M. Lu,60a Y. J. Lu,64 H. J. Lubatti,148 C. Luci,72a,72b
A Lucotte 58 C Luedtke 52 F Luehring 65 I Luise 136 L Luminari 72a B Lund-Jensen 154 M S Lutz 102 D Lynn 29 R. Lysak,141 E. Lytken,96 F. Lyu,15a V. Lyubushkin,79 T. Lyubushkina,79 H. Ma,29 L. L. Ma,60b Y. Ma,60b G. Maccarrone,51 g
y
J. Maeda,82 K. Maekawa,163 S. Maeland,17 T. Maeno,29 M. Maerker,48 A. S. Maevskiy,113 V. Magerl,52 N. Magini,78
D. J. Mahon,39 C. Maidantchik,80b T. Maier,114 A. Maio,140a,140b,140d O. Majersky,28a S. Majewski,131 Y. Makida,81
132
136
84
138
58
77
6
32 y
g
g
D. J. Mahon,39 C. Maidantchik,80b T. Maier,114 A. Maio,140a,140b,140d O. Majersky,28a S. Majewski,131 Y. Makida,81
N. Makovec,132 B. Malaescu,136 Pa. Malecki,84 V. P. Maleev,138 F. Malek,58 U. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Mehlhase,114
A Mehta 90 T Meideck 58 B Meirose 43 D Melini 174 B R Mellado Garcia 33c J D Mellenthin 53 M Melo 28a F Meloni 46 C. J. McNicol,178 R. A. McPherson,176,p J. E. Mdhluli,33c Z. A. Meadows,102 S. Meehan,148 T. Megy,52 S. Mehlhase,114
A. Mehta,90 T. Meideck,58 B. Meirose,43 D. Melini,174 B. R. Mellado Garcia,33c J. D. Mellenthin,53 M. Melo,28a F. Meloni,46 A. Mehta,90 T. Meideck,58 B. Meirose,43 D. Melini,174 B. R. Mellado Garcia,33c J. D. Mellenthin A. Melzer,24 S. B. Menary,100 E. D. Mendes Gouveia,140a,140e L. Meng,36 X. T. Meng,105 S. Menke,115 E. Meoni,41b,41a
19
139
20
54
69 69b
68
113 110 A. Melzer,24 S. B. Menary,100 E. D. Mendes Gouveia,140a,140e L. Meng,36 X. T. Meng,105 S. Menke,115 E. Meoni,41b,41a
S. Mergelmeyer,19 S. A. M. Merkt,139 C. Merlassino,20 P. Mermod,54 L. Merola,69a,69b C. Meroni,68a O. Meshkov,113,110
J K R M
h ki 151 A M
i
72a 72b J M t
lf
6 A S M t
171 C M
65 J M
160 J P M
145 S. Mergelmeyer,19 S. A. M. Merkt,139 C. Merlassino,20 P. Mermod,54 L. Merola,69a,69b C. Meroni,68a O. Meshkov,113,110
J. K. R. Meshreki,151 A. Messina,72a,72b J. Metcalfe,6 A. S. Mete,171 C. Meyer,65 J. Meyer,160 J-P. Meyer,145 H. Meyer Zu Theenhausen,
F. Miano,
R. P. Middleton,
L. Mijović,
G. Mikenberg,
M. Mikestikova,
M. Mikuž,91 H. Mildner,149 M. Milesi,104 A. Milic,167 D. A. Millar,92 D. W. Miller,37 A. Milov,180 D. A. Milstead,45a,45b y
,
,
,
j
,
g,
,
M. Mikuž,91 H. Mildner,149 M. Milesi,104 A. Milic,167 D. A. Millar,92 D. W. Miller,37 A. Milov,180 D. A. Milstead,45a,45b
R A Mi
153 dd A A Mi
k
123 M Miñ
M
174 I A Mi
h ili 159b A I Mi
124 B Mi d
83a M Mi
79 Y. Minegishi,163 Y. Ming,181 L. M. Mir,14 A. Mirto,67a,67b K. P. Mistry,137 T. Mitani,179 J. Mitrevski,114 V. A. Mitsou,174 M. Mittal,60c A. Miucci,20 P. S. Miyagawa,149 A. Mizukami,81 J. U. Mjörnmark,96 T. Mkrtchyan,184 M. Mlynarikova,143
T. Moa,45a,45b K. Mochizuki,109 P. Mogg,52 S. Mohapatra,39 R. Moles-Valls,24 M. C. Mondragon,106 K. Mönig,46 J. Monk,40
E M
i
101 A M
lb
152 J M
j
B li
36 M M
ll
94 F M
i
lli 88 S M
i 68a N M
132 y g
j
y
y
T. Moa,45a,45b K. Mochizuki,109 P. Mogg,52 S. Mohapatra,39 R. Moles-Valls,24 M. C. Mondragon,106 K. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Mallik,77 D. Malon,6 C. Malone,32 N. Makovec,132 B. Malaescu,136 Pa. Malecki,84 V. P. Maleev,138 F. Malek,58 U. Mallik,77 D. Malon,6 C. Malone,32 J. Manjarres Ramos,48 K. H. Mankinen,96 A. Mann,114 A. Manousos,76 B. Mansoulie,145 I. Manthos,162 S. Manzoni,120
A M
i
162 G M
30 L M
h
135 G M
hi
i 136 M M
i
k
141 C M
96 C A M i
T b
36 M. Marjanovic,38 Z. Marshall,18 M. U. F Martensson,172 S. Marti-Garcia,174 C. B. Martin,126 T. A. Martin,178 V. J. Martin,50
B. Martin dit Latour,17 L. Martinelli,74a,74b M. Martinez,14,u V. I. Martinez Outschoorn,102 S. Martin-Haugh,144 M. Marjanovic,38 Z. Marshall,18 M. U. F Martensson,172 S. Marti-Garcia,174 C. B. Martin,126 T. A. Martin,178 V. J. Martin,50
B. Martin dit Latour,17 L. Martinelli,74a,74b M. Martinez,14,u V. I. Martinez Outschoorn,102 S. Martin-Haugh,144
V. S. Martoiu,27b A. C. Martyniuk,94 A. Marzin,36 S. R. Maschek,115 L. Masetti,99 T. Mashimo,163 R. Mashinistov,110
J. Masik,100 A. L. Maslennikov,122b,122a L. H. Mason,104 L. Massa,73a,73b P. Massarotti,69a,69b P. Mastrandrea,71a,71b B. Martin dit Latour,
L. Martinelli,
,
M. Martinez,
, V. I. Martinez Outschoorn,
S. Martin-Haugh,
V. S. Martoiu,27b A. C. Martyniuk,94 A. Marzin,36 S. R. Maschek,115 L. Masetti,99 T. Mashimo,163 R. Mashinistov,110
J. Masik,100 A. L. Maslennikov,122b,122a L. H. Mason,104 L. Massa,73a,73b P. Massarotti,69a,69b P. Mastrandrea,71a,71b A. Mastroberardino,41b,41a T. Masubuchi,163 A. Matic,114 P. Mättig,24 J. Maurer,27b B. Maček,91 D. A. Maximov,122b,122a
158
162
146
105
115
94
18 R. Mazini,158 I. Maznas,162 S. M. Mazza,146 S. P. Mc Kee,105 T. G. McCarthy,115 L. I. McClymont,94 W. P. McCormack,18
E. F. McDonald,104 J. A. Mcfayden,36 M. A. McKay,42 K. D. McLean,176 S. J. McMahon,144 P. C. McNamara,104
C. J. McNicol,178 R. A. McPherson,176,p J. E. Mdhluli,33c Z. A. Meadows,102 S. Meehan,148 T. Megy,52 S. Mehlhase,114 R. Mazini,
I. Maznas,
S. M. Mazza,
S. P. Mc Kee,
T. G. McCarthy,
L. I. McClymont,
W. P. McCormack,
E. F. McDonald,104 J. A. Mcfayden,36 M. A. McKay,42 K. D. McLean,176 S. J. McMahon,144 P. C. McNamara,104
i
l 178
h
176 p
dhl li 33c
d
102
h
148
52
hlh
114 E. F. McDonald,104 J. A. Mcfayden,36 M. A. McKay,42 K. D. McLean,176 S. J. McMahon,144 P. C. McNamara,104
C. J. McNicol,178 R. A. McPherson,176,p J. E. Mdhluli,33c Z. A. Meadows,102 S. Meehan,148 T. Megy,52 S. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Palacino,65 S. Palazzo,50 S. Palestini,36 M. Palka,83b D. Pallin,38 I. Panagoulias,10 C. E. Pandini,36 J. G. Panduro Vazquez,93 P. Pani,46 G. Panizzo,66a,66c L. Paolozzi,54 C. Papadatos,109
K. Papageorgiou,9,r A. Paramonov,6 D. Paredes Hernandez,63b S. R. Paredes Saenz,135 B. Parida,166 T. H. Park,167 I. Panagoulias,
C. E. Pandini,
J. G. Panduro Vazquez,
P. Pani,
G. Panizzo,
L. Paolozzi,
C. Papadatos,
K. Papageorgiou,9,r A. Paramonov,6 D. Paredes Hernandez,63b S. R. Paredes Saenz,135 B. Parida,166 T. H. Park,167 A. J. Parker,89 M. A. Parker,32 F. Parodi,55b,55a E. W. P. Parrish,121 J. A. Parsons,39 U. Parzefall,52 L. Pascual Dominguez,136
V. R. Pascuzzi,167 J. M. P. Pasner,146 E. Pasqualucci,72a S. Passaggio,55b F. Pastore,93 P. Pasuwan,45a,45b S. Pataraia,99 J. R. Pater,100 A. Pathak,181 T. Pauly,36 B. Pearson,115 M. Pedersen,134 L. Pedraza Diaz,119 R. Pedro,140a T. Peiffer,53
S. V. Peleganchuk,122b,122a O. Penc,141 H. Peng,60a B. S. Peralva,80a M. M. Perego,132 A. P. Pereira Peixoto,140a
29
19
68 68b
36
69 69b
46
100
36 J. R. Pater,
A. Pathak,
T. Pauly,
B. Pearson,
M. Pedersen,
L. Pedraza Diaz,
R. Pedro,
T. Peiffer,
S. V. Peleganchuk,122b,122a O. Penc,141 H. Peng,60a B. S. Peralva,80a M. M. Perego,132 A. P. Pereira Peixoto,140a
D V P
lit
29 F P i 19 L P i i 68a 68b H P
36 S P
ll
69a 69b K P t
46 R F Y P t
100 B A P t
36 T. C. Petersen,40 E. Petit,101 A. Petridis,1 C. Petridou,162 P. Petroff,132 M. Petrov,135 F. Petrucci,74a,74b M. Pettee,183
N. E. Pettersson,102 K. Petukhova,143 A. Peyaud,145 R. Pezoa,147b L. Pezzotti,70a,70b T. Pham,104 F. H. Phillips,106
P. W. Phillips,144 M. W. Phipps,173 G. Piacquadio,155 E. Pianori,18 A. Picazio,102 R. H. Pickles,100 R. Piegaia,30
D Pietreanu 27b J E Pilcher 37 A D Pilkington 100 M Pinamonti 73a,73b J L Pinfold 3 M Pitt 180 L Pizzimento 73a,73b ,
,
y
,
,
,
,
p ,
P. W. Phillips,144 M. W. Phipps,173 G. Piacquadio,155 E. Pianori,18 A. Picazio,102 R. H. Pickles,100 R. Piegaia,30
D Pietreanu 27b J E Pilcher 37 A D Pilkington 100 M Pinamonti 73a,73b J L Pinfold 3 M Pitt 180 L Pizzimento 73a,73b p
pp
q
D. Pietreanu,27b J. E. Pilcher,37 A. D. Pilkington,100 M. Pinamonti,73a,73b J. L. Pinfold,3 M. Pitt, M.-A. Pleier,29 V. Pleskot,143 E. Plotnikova,79 D. Pluth,78 P. Podberezko,122b,122a R. Poettgen,96 R. Poggi,54 L. Poggioli,132
6
5 I. Pogrebnyak,106 D. Pohl,24 I. Pokharel,53 G. Polesello,70a A. D. Moreno,22 M. Moreno Llácer,36 C. Moreno Martinez,14 P. Morettini,55b M. Morgenstern,120 S. Morgenstern,48 D. Mori,152
M. Morii,59 M. Morinaga,179 V. Morisbak,134 A. K. Morley,36 G. Mornacchi,36 A. P. Morris,94 L. Morvaj,155
P. Moschovakos,36 B. Moser,120 M. Mosidze,159b T. Moskalets,145 H. J. Moss,149 J. Moss,31,jj K. Motohashi,165
E. Mountricha,36 E. J. W. Moyse,102 S. Muanza,101 J. Mueller,139 R. S. P. Mueller,114 D. Muenstermann,89 G. A. Mullier,96
J L M
M ti
14 F J M
S
h
100 P M
i
28b W J M
178 144 A M
68a 68b M M ški j
18 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Mönig,46 J. Monk,40 032007-27 PHYS. REV. D 100, 032007 (2019) G. AAD et al. I. Naryshkin,138 T. Naumann,46 G. Navarro,22 H. A. Neal,105,a P. Y. Nechaeva,110 F. Nechansky,46 T. J. Neep,21
A. Negri,70a,70b M. Negrini,23b C. Nellist,53 M. E. Nelson,135 S. Nemecek,141 P. Nemethy,124 M. Nessi,36,ll M. S. Neubauer,173 y
p
ni,23b C. Nellist,53 M. E. Nelson,135 S. Nemecek,141 P. Nemethy,124 M. Nessi,36,ll M. S. Neubauer, g
g
y
M. Neumann,182 P. R. Newman,21 T. Y. Ng,63c Y. S. Ng,19 Y. W. Y. Ng,171 H. D. N. Nguyen,101 T. Nguyen Manh,109
E. Nibigira,38 R. B. Nickerson,135 R. Nicolaidou,145 D. S. Nielsen,40 J. Nielsen,146 N. Nikiforou,11 V. Nikolaenko,123,kk g
g
y
M. Neumann,182 P. R. Newman,21 T. Y. Ng,63c Y. S. Ng,19 Y. W. Y. Ng,171 H. D. N. Nguyen,101 T. Nguyen Manh,109
38
135
145
40
146
11
123 kk I. Nikolic-Audit,136 K. Nikolopoulos,21 P. Nilsson,29 H. R. Nindhito,54 Y. Ninomiya,81 A. Nisati,72a N. Nishu,60c R. Nisius,115 I. Nitsche,47 T. Nitta,179 T. Nobe,163 Y. Noguchi,85 M. Nomachi,133 I. Nomidis,136 M. A. Nomura,29 M. Nordberg,36
N. Norjoharuddeen,135 T. Novak,91 O. Novgorodova,48 R. Novotny,142 L. Nozka,130 K. Ntekas,171 E. Nurse,94
34
115
136
82
39
147
26
87 S. Odaka,81 S. Oerdek,53 A. Ogrodnik,83a A. Oh,100 S. H. Oh,49 C. C. Ohm,154 H. Oide,55b,55a M. L. Ojeda,167 H. Okawa,169
Y. Okazaki,85 Y. Okumura,163 T. Okuyama,81 A. Olariu,27b L. F. Oleiro Seabra,140a S. A. Olivares Pino,147a S. Odaka,81 S. Oerdek,53 A. Ogrodnik,83a A. Oh,100 S. H. Oh,49 C. C. Ohm,154 H. Oide,55b,55a M. L. Ojeda,167 H. Okawa,169 y
D. Oliveira Damazio,29 J. L. Oliver,1 M. J. R. Olsson,171 A. Olszewski,84 J. Olszowska,84 D. C. O’Neil,152 A. Onofre,140a,140e E. Onyisi,11 H. Oppen,134 M. J. Oreglia,37 G. E. Orellana,88 D. Orestano,74a,74b N. Orlando,14 R. S Onogi,117 P. U. E. Onyisi,11 H. Oppen,134 M. J. Oreglia,37 G. E. Orellana,88 D. Orestano,74a,74b N
5
60
30
8
35d
134 V. O’Shea,57 R. Ospanov,60a G. Otero y Garzon,30 H. Otono,87 M. Ouchrif,35d F. Ould-Saada,134 A. Ouraou,145 Q. Ouyang,15a
M. Owen,57 R. E. Owen,21 V. E. Ozcan,12c N. Ozturk,8 J. Pacalt,130 H. A. Pacey,32 K. Pachal,49 A. Pacheco Pages,14 y
g
C. Padilla Aranda,14 S. Pagan Griso,18 M. Paganini,183 G. Palacino,65 S. Palazzo,50 S. Palestini,36 M. Palka,83b D. Pallin,38
li
10 C
di i 36
G
d
93
i 46 G
i
66a 66c
l
i 54 C
d
109 C. Padilla Aranda,14 S. Pagan Griso,18 M. Paganini,183 G. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Poley,18 A. Policicchio,72a,72b R. Polifka,143 A. Polini,23b
C. S. Pollard,46 V. Polychronakos,29 D. Ponomarenko,112 L. Pontecorvo,36 S. Popa,27a G. A. Popeneciu,27d I. Pogrebnyak,
D. Pohl,
I. Pokharel,
G. Polesello,
A. Poley,
A. Policicchio,
R. Polifka,
A. Polini,
C. S. Pollard,46 V. Polychronakos,29 D. Ponomarenko,112 L. Pontecorvo,36 S. Popa,27a G. A. Popeneciu,27d
58
142
46
79
32
11
96
36 D. M. Portillo Quintero,58 S. Pospisil,142 K. Potamianos,46 I. N. Potrap,79 C. J. Potter,32 H. Potti,11 T. Poulsen,96 J. Poveda,36
T. D. Powell,149 G. Pownall,46 M. E. Pozo Astigarraga,36 P. Pralavorio,101 S. Prell,78 D. Price,100 M. Primavera,67a
S. Prince,103 M. L. Proffitt,148 N. Proklova,112 K. Prokofiev,63c F. Prokoshin,147b S. Protopopescu,29 J. Proudfoot,6
M. Przybycien,83a D. Pudzha,138 A. Puri,173 P. Puzo,132 J. Qian,105 Y. Qin,100 A. Quadt,53 M. Queitsch-Maitland,46
A. Qureshi,1 P. Rados,104 F. Ragusa,68a,68b G. Rahal,97 J. A. Raine,54 S. Rajagopalan,29 A. Ramirez Morales,92 K. Ran,15a,15d
132
5
68 68b
46
114
99
149
180 M. Przybycien,
D. Pudzha,
A. Puri,
P. Puzo,
J. Qian,
Y. Qin,
A. Quadt,
M. Queitsch-Maitland,
A. Qureshi,1 P. Rados,104 F. Ragusa,68a,68b G. Rahal,97 J. A. Raine,54 S. Rajagopalan,29 A. Ramirez Morales,92 K. Ran,15a,15d Raspopov,5 M. G. Ratti,68a,68b D. M. Rauch,46 F. Rauscher,114 S. Rave,99 B. Ravina,149 I. Ravin p p
J. H. Rawling,100 M. Raymond,36 A. L. Read,134 N. P. Readioff,58 M. Reale,67a,67b D. M. Rebuzzi,70a,70b A. Redelbach,177 J. H. Rawling,100 M. Raymond,36 A. L. Read,134 N. P. Readioff,58 M. Reale,67a,67b D. M. Rebu J. H. Rawling,100 M. Raymond,36 A. L. Read,134 N. P. Readioff,58 M. Reale,67a,67b D. M. Rebuzzi,70a,70b A. Redelbach,177
G. Redlinger,29 K. Reeves,43 L. Rehnisch,19 J. Reichert,137 D. Reikher,161 A. Reiss,99 A. Rej,151 C. Rembser,36 M. Renda,27b
M. Rescigno,72a S. Resconi,68a E. D. Resseguie,137 S. Rettie,175 E. Reynolds,21 O. L. Rezanova,122b,122a P. Reznicek,143
E. Ricci,75a,75b R. Richter,115 S. Richter,46 E. Richter-Was,83b O. Ricken,24 M. Ridel,136 P. Rieck,115 C. J. Riegel,182
O. Rifki,46 M. Rijssenbeek,155 A. Rimoldi,70a,70b M. Rimoldi,20 L. Rinaldi,23b G. Ripellino,154 B. Ristić,89 E. Ritsch,36
I. Riu,14 J. C. Rivera Vergara,147a F. Rizatdinova,129 E. Rizvi,92 C. Rizzi,36 R. T. Roberts,100 S. H. Robertson,103,p M. Robin,46 M. Rescigno,72a S. Resconi,68a E. D. Resseguie,137 S. Rettie,175 E. Reynolds,21 O. L. Rezanova,122b,122a P. Reznicek,143
E. Ricci,75a,75b R. Richter,115 S. Richter,46 E. Richter-Was,83b O. Ricken,24 M. Ridel,136 P. Rieck,115 C. J. Riegel,182 g
O. Rifki,46 M. Rijssenbeek,155 A. Rimoldi,70a,70b M. Rimoldi,20 L. Rinaldi,23b G. Ripellino,154 B. Ristić,89 E. Ritsch,36
I. Riu,14 J. C. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Rivera Vergara,147a F. Rizatdinova,129 E. Rizvi,92 C. Rizzi,36 R. T. Roberts,100 S. H. Robertson,103,p M. Robin,46 032007-28 PHYS. REV. D 100, 032007 (2019) SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … D. Salihagic,115,a A. Salnikov,153 J. Salt,174 D. Salvatore,41b,41a F. Salvatore,156 A. Salvucci,63a,63b,63c A. Salzburger,36 J. Samarati,36 D. Sammel,52 D. Sampsonidis,162 D. Sampsonidou,162 J. Sánchez,174 A. Sanchez Pineda,66a,66c H. Sandaker,134
C. O. Sander,46 I. G. Sanderswood,89 M. Sandhoff,182 C. Sandoval,22 D. P. C. Sankey,144 M. Sannino,55b,55a Y. Sano,117 ,
,
p
,
p
,
,
,
,
C. O. Sander,46 I. G. Sanderswood,89 M. Sandhoff,182 C. Sandoval,22 D. P. C. Sankey,144 M. Sannino,55b,55a Y. Sano,117 A. Sansoni,
C. Santoni,
H. Santos,
S. N. Santpur,
A. Santra,
A. Sapronov,
J. G. Saraiva,
O. Sasaki,
K. Sato,169 E. Sauvan,5 P. Savard,167,e N. Savic,115 R. Sawada,163 C. Sawyer,144 L. Sawyer,95,nn C. Sbarra,23b A. Sbrizzi,23a
l
94
h
h id 148
h
h 115
h
h
114
h
f
37
h
f
137
h
ff
99 K. Sato,169 E. Sauvan,5 P. Savard,167,e N. Savic,115 R. Sawada,163 C. Sawyer,144 L. Sawyer,95,nn C. Sbarra,23b A. Sbrizzi,23a
T. Scanlon,94 J. Schaarschmidt,148 P. Schacht,115 B. M. Schachtner,114 D. Schaefer,37 L. Schaefer,137 J. Schaeffer,99 T. Scanlon,
J. Schaarschmidt,
P. Schacht,
B. M. Schachtner,
D. Schaefer,
L. Schaefer,
J. Schaeffer,
S. Schaepe,36 U. Schäfer,99 A. C. Schaffer,132 D. Schaile,114 R. D. Schamberger,155 N. Scharmberg,100 V. A. Schegelsky,138 D. Scheirich,143 F. Schenck,19 M. Schernau,171 C. Schiavi,55b,55a S. Schier,146 L. K. Schildgen,24 Z. M. Schillaci,26
E. J. Schioppa,36 M. Schioppa,41b,41a K. E. Schleicher,52 S. Schlenker,36 K. R. Schmidt-Sommerfeld,115 K. Schmieden,36 L. Serkin,66a,66b M. Sessa,60a H. Severini,128 F. Sforza,170 A. Sfyrla,54 E. Shabalina,53 J. D. Shahinian,146 N. W. Shaikh,45a,45b
D. Shaked Renous,180 L. Y. Shan,15a R. Shang,173 J. T. Shank,25 M. Shapiro,18 A. Sharma,135 A. S. Sharma,1
P. B. Shatalov,111 K. Shaw,156 S. M. Shaw,100 A. Shcherbakova,138 Y. Shen,128 N. Sherafati,34 A. D. Sherman,25
P. Sherwood,94 L. Shi,158,oo S. Shimizu,81 C. O. Shimmin,183 Y. Shimogama,179 M. Shimojima,116 I. P. J. Shipsey,135
S. Shirabe,87 M. Shiyakova,79,pp J. Shlomi,180 A. Shmeleva,110 M. J. Shochet,37 J. Shojaii,104 D. R. Shope,128 S. Shrestha,126
E. Shulga,180 P. Sicho,141 A. M. Sickles,173 P. E. Sidebo,154 E. Sideras Haddad,33c O. Sidiropoulou,36 A. Sidoti,23b,23a
F. Siegert,48 Dj. Sijacki,16 M. Silva Jr.,181 M. V. Silva Oliveira,80a S. B. Silverstein,45a S. Simion,132 E. Simioni,99 D. Shaked Renous,180 L. Y. Shan,15a R. Shang,173 J. T. Shank,25 M. Shapiro,18 A. Sharma,135 A. S. Sharma,1 P. B. Shatalov,111 K. Shaw,156 S. M. Shaw,100 A. Shcherbakova,138 Y. Shen,128 N. Sherafati,34 A. D. Sherman,25
P. Sherwood,94 L. Shi,158,oo S. Shimizu,81 C. O. D. Robinson,32 J. E. M. Robinson,46 A. Robson,57 E. Rocco,99 C. Roda,71a,71b S. Rodriguez Bosca,174 A. Rodriguez Perez,14
D. Rodriguez Rodriguez,174 A. M. Rodríguez Vera,168b S. Roe,36 O. Røhne,134 R. Röhrig,115 C. P. A. Roland,65 J. Roloff,59
A. Romaniouk,112 M. Romano,23b,23a N. Rompotis,90 M. Ronzani,124 L. Roos,136 S. Rosati,72a K. Rosbach,52 N-A. Rosien,53
G. Rosin,102 B. J. Rosser,137 E. Rossi,46 E. Rossi,74a,74b E. Rossi,69a,69b L. P. Rossi,55b L. Rossini,68a,68b R. Rosten,14
M. Rotaru,27b J. Rothberg,148 D. Rousseau,132 G. Rovelli,70a,70b D. Roy,33c A. Rozanov,101 Y. Rozen,160 X. Ruan,33c
F. Rubbo,153 F. Rühr,52 A. Ruiz-Martinez,174 A. Rummler,36 Z. Rurikova,52 N. A. Rusakovich,79 H. L. Russell,103
L. Rustige,38,47 J. P. Rutherfoord,7 E. M. Rüttinger,46,mm Y. F. Ryabov,138 M. Rybar,39 G. Rybkin,132 A. Ryzhov,123
G. F. Rzehorz,53 P. Sabatini,53 G. Sabato,120 S. Sacerdoti,132 H. F-W. Sadrozinski,146 R. Sadykov,79 F. Safai Tehrani,72a
B. Safarzadeh Samani,156 P. Saha,121 S. Saha,103 M. Sahinsoy,61a A. Sahu,182 M. Saimpert,46 M. Saito,163 T. Saito,163
H. Sakamoto,163 A. Sakharov,124,ee D. Salamani,54 G. Salamanna,74a,74b J. E. Salazar Loyola,147b P. H. Sales De Bruin,172
D. Salihagic,115,a A. Salnikov,153 J. Salt,174 D. Salvatore,41b,41a F. Salvatore,156 A. Salvucci,63a,63b,63c A. Salzburger,36
J. Samarati,36 D. Sammel,52 D. Sampsonidis,162 D. Sampsonidou,162 J. Sánchez,174 A. Sanchez Pineda,66a,66c H. Sandaker,134
C. O. Sander,46 I. G. Sanderswood,89 M. Sandhoff,182 C. Sandoval,22 D. P. C. Sankey,144 M. Sannino,55b,55a Y. Sano,117
A. Sansoni,51 C. Santoni,38 H. Santos,140a,140b S. N. Santpur,18 A. Santra,174 A. Sapronov,79 J. G. Saraiva,140a,140d O. Sasaki,81
K. Sato,169 E. Sauvan,5 P. Savard,167,e N. Savic,115 R. Sawada,163 C. Sawyer,144 L. Sawyer,95,nn C. Sbarra,23b A. Sbrizzi,23a
T. Scanlon,94 J. Schaarschmidt,148 P. Schacht,115 B. M. Schachtner,114 D. Schaefer,37 L. Schaefer,137 J. Schaeffer,99
S. Schaepe,36 U. Schäfer,99 A. C. Schaffer,132 D. Schaile,114 R. D. Schamberger,155 N. Scharmberg,100 V. A. Schegelsky,138
D. Scheirich,143 F. Schenck,19 M. Schernau,171 C. Schiavi,55b,55a S. Schier,146 L. K. Schildgen,24 Z. M. Schillaci,26
E. J. Schioppa,36 M. Schioppa,41b,41a K. E. Schleicher,52 S. Schlenker,36 K. R. Schmidt-Sommerfeld,115 K. Schmieden,36
C. Schmitt,99 S. Schmitt,46 S. Schmitz,99 J. C. Schmoeckel,46 U. Schnoor,52 L. Schoeffel,145 A. Schoening,61b E. Schopf,135
M. Schott,99 J. F. P. Schouwenberg,119 J. Schovancova,36 S. Schramm,54 F. Schroeder,182 A. Schulte,99
H-C. Schultz-Coulon,61a M. Schumacher,52 B. A. Schumm,146 Ph. Schune,145 A. Schwartzman,153 T. A. Schwarz,105
Ph. Schwemling,145 R. Schwienhorst,106 A. Sciandra,146 G. Sciolla,26 M. Scodeggio,46 M. Scornajenghi,41b,41a F. Scuri,71a
F. Scutti,104 L. M. Scyboz,115 C. D. Sebastiani,72a,72b P. Seema,19 S. C. Seidel,118 A. Seiden,146 T. Seiss,37 J. M. Seixas,80b
G. Sekhniaidze,69a K. Sekhon,105 S. J. Sekula,42 N. Semprini-Cesari,23b,23a S. Sen,49 S. Senkin,38 C. Serfon,76 L. Serin,132
L. Serkin,66a,66b M. Sessa,60a H. Severini,128 F. Sforza,170 A. Sfyrla,54 E. Shabalina,53 J. D. Shahinian,146 N. W. Shaikh,45a,45b
D. Shaked Renous,180 L. Y. Shan,15a R. Shang,173 J. T. Shank,25 M. Shapiro,18 A. Sharma,135 A. S. Sharma,1
P B Sh t l
111 K Sh
156 S M Sh
100 A Sh h b k
138 Y Sh
128 N Sh
f ti 34 A D Sh
25 T. Sykora,143 D. Ta,99 K. Tackmann,46,ss J. Taenzer,161 A. Taffard,171 R. Tafirout,168a E. Tahirovic,92 H. Takai,29
R. Takashima,86 K. Takeda,82 T. Takeshita,150 E. P. Takeva,50 Y. Takubo,81 M. Talby,101 A. A. Talyshev,122b,122a
N. M. Tamir,161 J. Tanaka,163 M. Tanaka,165 R. Tanaka,132 B. B. Tannenwald,126 S. Tapia Araya,173 S. Tapprogge,99
A. Tarek Abouelfadl Mohamed,136 S. Tarem,160 G. Tarna,27b,tt G. F. Tartarelli,68a P. Tas,143 M. Tasevsky,141 T. Tashiro,85
E. Tassi,41b,41a A. Tavares Delgado,140a,140b Y. Tayalati,35e A. J. Taylor,50 G. N. Taylor,104 W. Taylor,168b A. S. Tee,89
R. Teixeira De Lima,153 P. Teixeira-Dias,93 H. Ten Kate,36 J. J. Teoh,120 S. Terada,81 K. Terashi,163 J. Terron,98 S. Terzo,14
M. Testa,51 R. J. Teuscher,167,p S. J. Thais,183 T. Theveneaux-Pelzer,46 F. Thiele,40 D. W. Thomas,93 J. O. Thomas,42
J. P. Thomas,21 A. S. Thompson,57 P. D. Thompson,21 L. A. Thomsen,183 E. Thomson,137 Y. Tian,39 R. E. Ticse Torres,53
V. O. Tikhomirov,110,uu Yu. A. Tikhonov,122b,122a S. Timoshenko,112 P. Tipton,183 S. Tisserant,101 K. Todome,23b,23a
S. Todorova-Nova,5 S. Todt,48 J. Tojo,87 S. Tokár,28a K. Tokushuku,81 E. Tolley,126 K. G. Tomiwa,33c M. Tomoto,117
L. Tompkins,153,dd K. Toms,118 B. Tong,59 P. Tornambe,102 E. Torrence,131 H. Torres,48 E. Torró Pastor,148 C. Tosciri,135
J. Toth,101,vv D. R. Tovey,149 C. J. Treado,124 T. Trefzger,177 F. Tresoldi,156 A. Tricoli,29 I. M. Trigger,168a
S. Trincaz-Duvoid,136 W. Trischuk,167 B. Trocm´e,58 A. Trofymov,132 C. Troncon,68a M. Trovatelli,176 F. Trovato,156
L. Truong,33b M. Trzebinski,84 A. Trzupek,84 F. Tsai,46 J. C-L. Tseng,135 P. V. Tsiareshka,107,ff A. Tsirigotis,162
N. Tsirintanis,9 V. Tsiskaridze,155 E. G. Tskhadadze,159a M. Tsopoulou,162 I. I. Tsukerman,111 V. Tsulaia,18 S. Tsuno,81
D. Tsybychev,155 Y. Tu,63b A. Tudorache,27b V. Tudorache,27b T. T. Tulbure,27a A. N. Tuna,59 S. Turchikhin,79
D. Turgeman,180 I. Turk Cakir,4b,ww R. J. Turner,21 R. T. Turra,68a P. M. Tuts,39 S. Tzamarias,162 E. Tzovara,99 G. Ucchielli,47
K. Uchida,163 I. Ueda,81 M. Ughetto,45a,45b F. Ukegawa,169 G. Unal,36 A. Undrus,29 G. Unel,171 F. C. Ungaro,104 Y. Unno,81
K. Uno,163 J. Urban,28b P. Urquijo,104 G. Usai,8 J. Usui,81 L. Vacavant,101 V. Vacek,142 B. Vachon,103 K. O. H. Vadla,134
A Vaidya 94 C Valderanis 114 E Valdes Santurio 45a,45b M Valente 54 S Valentinetti 23b,23a A Valero 174 L Val´ery 46 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Shimmin,183 Y. Shimogama,179 M. Shimojima,116 I. P. J. Shipsey,135
S. Shirabe,87 M. Shiyakova,79,pp J. Shlomi,180 A. Shmeleva,110 M. J. Shochet,37 J. Shojaii,104 D. R. Shope,128 S. Shrestha,126
E. Shulga,180 P. Sicho,141 A. M. Sickles,173 P. E. Sidebo,154 E. Sideras Haddad,33c O. Sidiropoulou,36 A. Sidoti,23b,23a R. Simoniello,99 P. Sinervo,167 N. B. Sinev,131 M. Sioli,23b,23a I. Siral,105 S. Yu. Sivoklokov,113 J. Sjölin,45a,45b E. Skorda,96 ,
,
,
,
,
,
,
,
S. Yu. Smirnov,112 Y. Smirnov,112 L. N. Smirnova,113,qq O. Smirnova,96 J. W. Smith,53 M. Smizanska,89 K. Smolek,142
84
110
120
131
29
176 p
171
161 P. Steinberg,29 A. L. Steinhebel,131 B. Stelzer,152 H. J. Stelzer,139 O. Stelzer-Chilton,168a H. Stenzel,56 T. J. Stevenson,156 032007-29 PHYS. REV. D 100, 032007 (2019) G. AAD et al. D. Turgeman,180 I. Turk Cakir,4b,ww R. J. Turner,21 R. T. Turra,68a P. M. Tuts,39 S. Tzamarias,162 E. Tzovara,99 G. Ucchielli,47 K. Uchida,163 I. Ueda,81 M. Ughetto,45a,45b F. Ukegawa,169 G. Unal,36 A. Undrus,29 G. Unel,171 K. Uno,163 J. Urban,28b P. Urquijo,104 G. Usai,8 J. Usui,81 L. Vacavant,101 V. Vacek,142 B. Vachon,103 K. O. H. Vadla,134 A. Vaidya,94 C. Valderanis,114 E. Valdes Santurio,45a,45b M. Valente,54 S. Valentinetti,23b,23a A. Valero,174 L. Val´ery,46
R. A. Vallance,21 A. Vallier,36 J. A. Valls Ferrer,174 T. R. Van Daalen,14 P. Van Gemmeren,6 I. Van Vulpen,120
M V
di
73a 73b W V
d lli 36 A V
i
hi
166 D V
i
l
72a 72b R V i 72a E W V
7 C V
i 55b 55a T V
l 42 y ,
,
,
,
,
,
y,
R. A. Vallance,21 A. Vallier,36 J. A. Valls Ferrer,174 T. R. Van Daalen,14 P. Van Gemmeren,6 I. Van Vulpen,120
M Vanadia 73a,73b W Vandelli 36 A Vaniachine 166 D Vannicola 72a,72b R Vari 72a E W Varnes 7 C Varni 55b,55a T Varol 42 R. A. Vallance,21 A. Vallier,36 J. A. Valls Ferrer,174 T. R. Van Daalen,14 P. Van Gemmeren,6 I. Van Vulpen,120
M. Vanadia,73a,73b W. Vandelli,36 A. Vaniachine,166 D. Vannicola,72a,72b R. Vari,72a E. W. Varnes,7 C. Varni,55b,55a T. Varol,42
132
157
27b
176
183
38
14 D. Varouchas,132 K. E. Varvell,157 M. E. Vasile,27b G. A. Vasquez,176 J. G. Vasquez,183 F. Vazeille,38 D. Vazquez Furelos,14
T V
S h
d
36 J V
h 53 V V
hi
74a 74b M J V
120 L M V l
167 F V l
140a 140c S V
i
72a D. Varouchas,132 K. ,
g,
g
,
,
,
,
,
g
,
S. Wenig,36 N. Wermes,24 M. D. Werner,78 P. Werner,36 M. Wessels,61a T. D. Weston,20 K. Whalen,131 N. L. Whallon,148
A. M. Wharton,89 A. S. White,105 A. White,8 M. J. White,1 D. Whiteson,171 B. W. Whitmore,89 F. J. Wickens,144
W. Wiedenmann,181 M. Wielers,144 N. Wieseotte,99 C. Wiglesworth,40 L. A. M. Wiik-Fuchs,52 F. Wilk,100 H. G. Wilkens,36
L. J. Wilkins,93 H. H. Williams,137 S. Williams,32 C. Willis,106 S. Willocq,102 J. A. Wilson,21 I. Wingerter-Seez,5
E. Winkels,156 F. Winklmeier,131 O. J. Winston,156 B. T. Winter,52 M. Wittgen,153 M. Wobisch,95 A. Wolf,99 T. M. H. Wolf,120
R. Wolff,101 R. W. Wölker,135 J. Wollrath,52 M. W. Wolter,84 H. Wolters,140a,140c V. W. S. Wong,175 N. L. Woods,146
S. D. Worm,21 B. K. Wosiek,84 K. W. Woźniak,84 K. Wraight,57 S. L. Wu,181 X. Wu,54 Y. Wu,60a T. R. Wyatt,100
B. M. Wynne,50 S. Xella,40 Z. Xi,105 L. Xia,178 D. Xu,15a H. Xu,60a,tt L. Xu,29 T. Xu,145 W. Xu,105 Z. Xu,60b Z. Xu,153
B. Yabsley,157 S. Yacoob,33a K. Yajima,133 D. P. Yallup,94 D. Yamaguchi,165 Y. Yamaguchi,165 A. Yamamoto,81
T. Yamanaka,163 F. Yamane,82 M. Yamatani,163 T. Yamazaki,163 Y. Yamazaki,82 Z. Yan,25 H. J. Yang,60c,60d H. T. Yang,18
S. Yang,77 X. Yang,60b,58 Y. Yang,163 Z. Yang,17 W-M. Yao,18 Y. C. Yap,46 Y. Yasu,81 E. Yatsenko,60c,60d J. Ye,42 S. Ye,29
I. Yeletskikh,79 M. R. Yexley,89 E. Yigitbasi,25 E. Yildirim,99 K. Yorita,179 K. Yoshihara,137 C. J. S. Young,36 C. Young,153 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … J. Yu,78 R. Yuan,60b X. Yue,61a S. P. Y. Yuen,24 B. Zabinski,84 G. Zacharis,10 E. Zaffaroni,54 J. Zahreddine,136 R. Zaidan,14
A. M. Zaitsev,123,kk T. Zakareishvili,159b N. Zakharchuk,34 S. Zambito,59 D. Zanzi,36 D. R. Zaripovas,57 S. V. Zeißner,47
C. Zeitnitz,182 G. Zemaityte,135 J. C. Zeng,173 O. Zenin,123 D. Zerwas,132 M. Zgubič,135 D. F. Zhang,15b F. Zhang,181
G. Zhang,60a G. Zhang,15b H. Zhang,15c J. Zhang,6 L. Zhang,15c L. Zhang,60a M. Zhang,173 R. Zhang,60a R. Zhang,24
X. Zhang,60b Y. Zhang,15a,15d Z. Zhang,63a Z. Zhang,132 P. Zhao,49 Y. Zhao,60b Z. Zhao,60a A. Zhemchugov,79 Z. Zheng,105
D. Zhong,173 B. Zhou,105 C. Zhou,181 M. S. Zhou,15a,15d M. Zhou,155 N. Zhou,60c Y. Zhou,7 C. G. Zhu,60b H. L. Zhu,60a
H. Zhu,15a J. Zhu,105 Y. Zhu,60a X. Zhuang,15a K. Zhukov,110 V. Zhulanov,122b,122a D. Zieminska,65 N. I. Zimine,79
S. Zimmermann,52 Z. Zinonos,115 M. Ziolkowski,151 G. Zobernig,181 A. Zoccoli,23b,23a K. Zoch,53 T. G. Zorbas,149
37
36 R. Zou,37 and L. Zwalinski36 R. Zou,37 and L. Zwalinski36 SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … E. Varvell,157 M. E. Vasile,27b G. A. Vasquez,176 J. G. Vasquez,183 F. Vazeille,38 D. Vazquez Furelos,14
T. Vazquez Schroeder,36 J. Veatch,53 V. Vecchio,74a,74b M. J. Veen,120 L. M. Veloce,167 F. Veloso,140a,140c S. Veneziano,72a q
A. Ventura,67a,67b N. Venturi,36 A. Verbytskyi,115 V. Vercesi,70a M. Verducci,74a,74b C. M. Vergel Infante,78 C. Vergis,24 uri,36 A. Verbytskyi,115 V. Vercesi,70a M. Verducci,74a,74b C. M. Vergel Infante,78 C. Vergis,24
120
120
152
147b
54 W. Verkerke,120 A. T. Vermeulen,120 J. C. Vermeulen,120 M. C. Vetterli,152,e N. Viaux Maira,147b M. Vicente Barreto Pinto,54
T. Vickey,149 O. E. Vickey Boeriu,149 G. H. A. Viehhauser,135 L. Vigani,135 M. Villa,23b,23a M. Villaplana Perez,68a,68b T. Vickey,149 O. E. Vickey Boeriu,149 G. H. A. Viehhauser,135 L. Vigani,135 M. Villa,23b,23a M. Villaplana Perez,68a,68b P. Vokac,142 S. E. von Buddenbrock,33c E. Von Toerne,24 V. Vorobel,143 K. Vorobev,112 M. Vos,174 J. H. Vossebeld,90 N. Vranjes,16 M. Vranjes Milosavljevic,16 V. Vrba,142 M. Vreeswijk,120 T. Šfiligoj,91 R. Vuillermet,36 I. Vukotic,37
T. Ženiš,28a L. Živković,16 P. Wagner,24 W. Wagner,182 J. Wagner-Kuhr,114 H. Wahlberg,88 K. Wakamiya,82 032007-30 PHYS. REV. D 100, 032007 (2019) EARCH FOR ELECTROWEAK DIBOSON PRODUCTION … (ATLAS Collaboration) 1Department of Physics, University of Adelaide, Adelaide, Australia
2Physics Department, SUNY Albany, Albany, New York, USA
3Department of Physics, University of Alberta, Edmonton, Alberta, Canada
4aDepartment of Physics, Ankara University, Ankara, Turkey
4bIstanbul Aydin University, Istanbul, Turkey
4cDivision of Physics, TOBB University of Economics and Technology, Ankara, Turkey
5LAPP, Universit´e Grenoble Alpes, Universit´e Savoie Mont Blanc, CNRS/IN2P3, Annecy, France
6High Energy Physics Division, Argonne National Laboratory, Argonne, Illinois, USA
7Department of Physics, University of Arizona, Tucson, Arizona, USA
8Department of Physics, University of Texas at Arlington, Arlington, Texas, USA
9Physics Department, National and Kapodistrian University of Athens, Athens, Greece
10Physics Department, National Technical University of Athens, Zografou, Greece
11Department of Physics, University of Texas at Austin, Austin, Texas, USA
12aBahcesehir University, Faculty of Engineering and Natural Sciences, Istanbul, Turkey
12bIstanbul Bilgi University, Faculty of Engineering and Natural Sciences, Istanbul, Turkey
12cDepartment of Physics, Bogazici University, Istanbul, Turkey
12dDepartment of Physics Engineering, Gaziantep University, Gaziantep, Turkey
13Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan
14Institut de Física d’Altes Energies (IFAE), Barcelona Institute of Science and Technology,
Barcelona, Spain
15aInstitute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
15bPhysics Department, Tsinghua University, Beijing, China
15cDepartment of Physics, Nanjing University, Nanjing, China
15dUniversity of Chinese Academy of Science (UCAS), Beijing, China
16Institute of Physics, University of Belgrade, Belgrade, Serbia
17Department for Physics and Technology, University of Bergen, Bergen, Norway
18Physics Division, Lawrence Berkeley National Laboratory and University of California,
Berkeley, California, USA
19Institut für Physik, Humboldt Universität zu Berlin, Berlin, Germany
20Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics,
University of Bern, Bern, Switzerland
21School of Physics and Astronomy, University of Birmingham, Birmingham, United Kingdom
22Facultad de Ciencias y Centro de Investigaciónes, Universidad Antonio Nariño, Bogota, Colombia
23aINFN Bologna and Universita’ di Bologna, Dipartimento di Fisica, Italy
23bINFN Sezione di Bologna, Italy
24Physikalisches Institut, Universität Bonn, Bonn, Germany
25Department of Physics, Boston University, Boston, Massachusetts, USA
26Department of Physics, Brandeis University, Waltham, Massachusetts, USA
27aTransilvania University of Brasov, Brasov, Romania
27bHoria Hulubei National Institute of Physics and Nuclear Engineering, Bucharest, Romania
27cDepartment of Physics, Alexandru Ioan Cuza University of Iasi, Iasi, Romania
27dNational Institute for Research and Development of Isotopic and Molecular Technologies,
Physics Department, Cluj-Napoca, Romania
27eUniversity Politehnica Bucharest, Bucharest, Romania
27fWest University in Timisoara, Timisoara, Romania
28aFaculty of Mathematics, Physics and Informatics, Comenius University, Bratislava, Slovak Republic Berkeley, California, USA 19Institut für Physik, Humboldt Universität zu Berlin, Berlin, Germany 20Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics, Einstein Center for Fundamental Physics and Laboratory for High Energy Physics, University of Bern, Bern, Switzerland l of Physics and Astronomy, University of Birmingham, Birmingham, United Kingdom 21School of Physics and Astronomy, University of Birmingham, Birmingham, United Kingdom
22 22Facultad de Ciencias y Centro de Investigaciónes, Universidad Antonio Nariño, Bogota, Colombia
23aINFN Bologna and Universita’ di Bologna, Dipartimento di Fisica, Italy
23b ad de Ciencias y Centro de Investigaciónes, Universidad Antonio Nariño, Bogota, Colombia
23aINFN Bologna and Universita’ di Bologna, Dipartimento di Fisica, Italy
23b Physics Department, Cluj-Napoca, Romania Physics Department, Cluj-Napoca, Romania 27eUniversity Politehnica Bucharest, Bucharest, Romania
27f 27eUniversity Politehnica Bucharest, Bucharest, Romania
27f 27fWest University in Timisoara, Timisoara, Romania 28aFaculty of Mathematics, Physics and Informatics, Comenius University, Bratislava, Slovak Republic 23bINFN Sezione di Bologna, Italy 24Physikalisches Institut, Universität Bonn, Bonn, Germany 25Department of Physics, Boston University, Boston, Massachusetts, USA
6 25Department of Physics, Boston University, Boston, Massachusetts, USA
6 26Department of Physics, Brandeis University, Waltham, Massachusetts, USA
27 26Department of Physics, Brandeis University, Waltham, Massachusetts, USA
27 Transilvania University of Brasov, Brasov, Romania 27aTransilvania University of Brasov, Brasov, Romania
b 27bHoria Hulubei National Institute of Physics and Nuclear Engineering, Bucharest, Romania
27 27cDepartment of Physics, Alexandru Ioan Cuza University of Iasi, Iasi, Romania
27d 27dNational Institute for Research and Development of Isotopic and Molecular Technologies, 55bINFN Sezione di Genova, Italy 60cSchool of Physics and Astronomy, Shanghai Jiao Tong University, KLPPAC-MoE, SKLPPC, Shanghai, China
60d Tsung Dao Lee Institute, Shanghai, China
61aKirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
61bPhysikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
62Faculty of Applied Information Science, Hiroshima Institute of Technology, Hiroshima, Japan
63aDepartment of Physics, Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
63bDepartment of Physics, University of Hong Kong, Hong Kong, China
63cDepartment of Physics and Institute for Advanced Study, Hong Kong University of Science and
Technology, Clear Water Bay, Kowloon, Hong Kong, China
64Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
65Department of Physics, Indiana University, Bloomington, Indiana, USA 64Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
65 65Department of Physics, Indiana University, Bloomington, Indiana, USA 032007-31 032007-31 28bDepartment of Subnuclear Physics, Institute of Experimental Physics of the Slovak Academy of Sciences,
Kosice, Slovak Republic
29Physics Department, Brookhaven National Laboratory, Upton, New York, USA
30Departamento de Física, Universidad de Buenos Aires, Buenos Aires, Argentina
31California State University, California, USA
32Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom
33aDepartment of Physics, University of Cape Town, Cape Town, South Africa
33bDepartment of Mechanical Engineering Science, University of Johannesburg,
Johannesburg, South Africa
33cSchool of Physics, University of the Witwatersrand, Johannesburg, South Africa
34Department of Physics, Carleton University, Ottawa, Ontario, Canada
35aFacult´e des Sciences Ain Chock, R´eseau Universitaire de Physique des Hautes Energies—Universit´e
Hassan II, Casablanca, Morocco
35bFacult´e des Sciences, Universit´e Ibn-Tofail, K´enitra, Morocco
35cFacult´e des Sciences Semlalia, Universit´e Cadi Ayyad, LPHEA-Marrakech, Morocco
35dFacult´e des Sciences, Universit´e Mohamed Premier and LPTPM, Oujda, Morocco
35eFacult´e des sciences, Universit´e Mohammed V, Rabat, Morocco
36CERN, Geneva, Switzerland
37Enrico Fermi Institute, University of Chicago, Chicago, Illinois, USA
38LPC, Universit´e Clermont Auvergne, CNRS/IN2P3, Clermont-Ferrand, France
39Nevis Laboratory, Columbia University, Irvington, New York, USA
40Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
41aDipartimento di Fisica, Universit`a della Calabria, Rende, Italy
41bINFN Gruppo Collegato di Cosenza, Laboratori Nazionali di Frascati, Italy
42Physics Department, Southern Methodist University, Dallas, Texas, USA
43Physics Department, University of Texas at Dallas, Richardson, Texas, USA
44National Centre for Scientific Research “Demokritos”, Agia Paraskevi, Greece
45aDepartment of Physics, Stockholm University, Sweden
45bOskar Klein Centre, Stockholm, Sweden
46Deutsches Elektronen-Synchrotron DESY, Hamburg and Zeuthen, Germany
47Lehrstuhl für Experimentelle Physik IV, Technische Universität Dortmund, Dortmund, Germany
48Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden, Germany
49Department of Physics, Duke University, Durham, North Carolina, USA
50SUPA—School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
51INFN e Laboratori Nazionali di Frascati, Frascati, Italy
52Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
53II. Physikalisches Institut, Georg-August-Universität Göttingen, Göttingen, Germany
54D´epartement de Physique Nucl´eaire et Corpusculaire, Universit´e de Gen`eve, Gen`eve, Switzerland
55aDipartimento di Fisica, Universit`a di Genova, Genova, Italy
55bINFN Sezione di Genova, Italy
56II. 032007-31 Physikalisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany
57SUPA—School of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
58LPSC, Universit´e Grenoble Alpes, CNRS/IN2P3, Grenoble INP, Grenoble, France
59Laboratory for Particle Physics and Cosmology, Harvard University, Cambridge, Massachusetts, USA
60aDepartment of Modern Physics and State Key Laboratory of Particle Detection and Electronics,
University of Science and Technology of China, Hefei, China
60bInstitute of Frontier and Interdisciplinary Science and Key Laboratory of Particle Physics
and Particle Irradiation (MOE), Shandong University, Qingdao, China
60cSchool of Physics and Astronomy, Shanghai Jiao Tong University,
KLPPAC-MoE, SKLPPC, Shanghai, China
60dTsung-Dao Lee Institute, Shanghai, China
61aKirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
61bPhysikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
62Faculty of Applied Information Science, Hiroshima Institute of Technology, Hiroshima, Japan
63aDepartment of Physics, Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
63bDepartment of Physics, University of Hong Kong, Hong Kong, China
63cDepartment of Physics and Institute for Advanced Study, Hong Kong University of Science and
Technology, Clear Water Bay, Kowloon, Hong Kong, China
64Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
65Department of Physics Indiana University Bloomington Indiana USA
et al. PHYS. REV. D 100, 032007 (2 PHYS. REV. D 100, 032007 (2019) G. AAD et al. 28bDepartment of Subnuclear Physics, Institute of Experimental Physics of the Slovak Academy of Sciences,
Kosice, Slovak Republic Fukuoka, Japan p
88Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La P
89Ph
i
D
t
t L
t
U i
it
L
t
U it d Ki
d p
88Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La Plata, Argentin
89 89Physics Department, Lancaster University, Lancaster, United Kingdom
90 90Oliver Lodge Laboratory, University of Liverpool, Liverpool, United Kingdom
91Department of Experimental Particle Physics, Jožef Stefan Institute and Department of Physics,
University of Ljubljana, Ljubljana, Slovenia
92 92School of Physics and Astronomy, Queen Mary University of London, London, United Kingdom
93Department of Physics, Royal Holloway University of London, Egham, United Kingdom
94 92School of Physics and Astronomy, Queen Mary University of London, London, United Kingdom
93Department of Physics, Royal Holloway University of London, Egham, United Kingdom
94Department of Physics and Astronomy, University College London, London, United Kingdom
95Louisiana Tech University, Ruston, Louisiana, USA 94Department of Physics and Astronomy, University College London, London, United Kingdom
95Louisiana Tech University, Ruston, Louisiana, USA 95Louisiana Tech University, Ruston, Louisiana, USA
96 96Fysiska institutionen, Lunds universitet, Lund, Sweden
97 ysiska institutionen, Lunds universitet, Lund, Swede 97Centre de Calcul de l’Institut National de Physique Nucl´eaire et de Physique des Particules (IN2P tut National de Physique Nucl´eaire et de Physique 032007-32 032007-32 PHYS. REV. D 100, 032007 (2019) SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … 66aINFN Gruppo Collegato di Udine, Sezione di Trieste, Udine, Italy
66b 66aINFN Gruppo Collegato di Udine, Sezione di Trieste, Udine, Italy g
66bICTP, Trieste, Italy y
66cDipartimento Politecnico di Ingegneria e Architettura, Universit`a di Udine, Udine, Italy
67a y
67bDipartimento di Matematica e Fisica, Universit`a del Salento, Lecce, Italy
68 68aINFN Sezione di Milano, Italy 68bDipartimento di Fisica, Universit`a di Milano, Milano, Italy
69 p
y
69bDipartimento di Fisica, Universit`a di Napoli, Napoli, Italy
0 p
y
69bDipartimento di Fisica, Universit`a di Napoli, Napoli, Italy
70 70aINFN Sezione di Pavia, Italy 70bDipartimento di Fisica, Universit`a di Pavia, Pavia, Italy
71 70bDipartimento di Fisica, Universit`a di Pavia, Pavia, Italy
71 y
71bDipartimento di Fisica E. Fermi, Universit`a di Pisa, Pisa, Italy 71bDipartimento di Fisica E. Fermi, Universit`a di Pisa, Pisa, Italy
72 y
72bDipartimento di Fisica, Sapienza Universit`a di Roma, Roma, Italy
73 72bDipartimento di Fisica, Sapienza Universit`a di Roma, Roma, Italy
73 73aINFN Sezione di Roma Tor Vergata, Italy 73aINFN Sezione di Roma Tor Vergata, Italy 73bDipartimento di Fisica, Universit`a di Roma Tor Vergata, Roma, Italy
74 73bDipartimento di Fisica, Universit`a di Roma Tor Vergata, Roma, Italy
74 74bDipartimento di Matematica e Fisica, Universit`a Roma Tre, Roma, Italy
75 75aINFN-TIFPA, Italy y
75bUniversit`a degli Studi di Trento, Trento, Italy 76Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität, Innsbruck, Austria
77 77University of Iowa, Iowa City, Iowa, USA
78 78Department of Physics and Astronomy, Iowa State University, Ames, Iowa, USA
79 79Joint Institute for Nuclear Research, Dubna, Russia f
,
,
80aDepartamento de Engenharia El´etrica, Universidade Federal de Juiz de Fora (UFJF),
Juiz de Fora Brazil partamento de Engenharia El´etrica, Universidade Federal de Juiz de Fora (UFJF), Villeurbanne, France 98Departamento de Física Teorica C-15 and CIAFF, Universidad Autónoma de Madrid, Madrid, Spa
99 99Institut für Physik, Universität Mainz, Mainz, Germany
100 100School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom
101CPPM, Aix-Marseille Universit´e, CNRS/IN2P3, Marseille, France 102Department of Physics, University of Massachusetts, Amherst, Massachusetts, USA
103Department of Physics, McGill University, Montreal, Quebec, Canada
104School of Physics, University of Melbourne, Victoria, Australia 102Department of Physics, University of Massachusetts, Amherst, Massachusetts, USA
103 102Department of Physics, University of Massachusetts, Amherst, Massachusetts, USA
103Department of Physics McGill University Montreal Quebec Canada Department of Physics, University of Massachusetts, Amherst, Massachusetts, US
103Department of Physics, McGill University, Montreal, Quebec, Canada
104 104School of Physics, University of Melbourne, Victoria, Australia 105Department of Physics, University of Michigan, Ann Arbor, Michigan, USA Juiz de Fora, Brazil 80bUniversidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro, Brazil
80cUniversidade Federal de São João del Rei (UFSJ), São João del Rei, Brazil
80dInstituto de Física, Universidade de São Paulo, São Paulo, Brazil
81KEK, High Energy Accelerator Research Organization, Tsukuba, Japan
82 80bUniversidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro, Brazil
80cU i
id d F d
l d Sã
J ã
d l R i (UFSJ) Sã
J ã
d l R i B
il te School of Science, Kobe University, Kobe, Japan 83aAGH University of Science and Technology, Faculty of Physics and Applied Computer Science,
Krakow Poland Krakow, Poland 83bMarian Smoluchowski Institute of Physics, Jagiellonian University, Krakow, Poland
84 84Institute of Nuclear Physics Polish Academy of Sciences, Krakow, Poland
85 85Faculty of Science, Kyoto University, Kyoto, Japan
86 86Kyoto University of Education, Kyoto, Japan 86Kyoto University of Education, Kyoto, Japan 87Research Center for Advanced Particle Physics and Department of Physics, Kyushu University, PNPI, St. Petersburg, Russia 139Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
140aLaboratório de Instrumentação e Física Experimental de Partículas—LIP, Portugal
140b ç
p
,
g
140bDepartamento de Física, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
140cDepartamento de Física, Universidade de Coimbra, Coimbra, Portugal
140dCentro de Física Nuclear da Universidade de Lisboa, Lisboa, Portugal
140eDepartamento de Física, Universidade do Minho, Braga, Portugal
140fUniversidad de Granada, Granada (Spain), Spain
140gDep Física and CEFITEC of Faculdade de Ciências e Tecnologia,
Universidade Nova de Lisboa, Caparica, Portugal
141Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic
142Czech Technical University in Prague, Prague, Czech Republic
143Charles University, Faculty of Mathematics and Physics, Prague, Czech Republic
144Particle Physics Department, Rutherford Appleton Laboratory, Didcot, United Kingdom
145IRFU, CEA, Universit´e Paris-Saclay, Gif-sur-Yvette, France
146Santa Cruz Institute for Particle Physics University of California Santa Cruz ç
p
g
140bDepartamento de Física, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
140cDepartamento de Física, Universidade de Coimbra, Coimbra, Portugal
140dCentro de Física Nuclear da Universidade de Lisboa, Lisboa, Portugal
140eDepartamento de Física, Universidade do Minho, Braga, Portugal
140fUniversidad de Granada, Granada (Spain), Spain
140gDep Física and CEFITEC of Faculdade de Ciências e Tecnologia,
Universidade Nova de Lisboa, Caparica, Portugal
141Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic
142Czech Technical University in Prague, Prague, Czech Republic
143Charles University, Faculty of Mathematics and Physics, Prague, Czech Republic
144Particle Physics Department, Rutherford Appleton Laboratory, Didcot, United Kingdom
145IRFU, CEA, Universit´e Paris-Saclay, Gif-sur-Yvette, France
146Santa Cruz Institute for Particle Physics, University of California Santa Cruz,
Santa Cruz, California, USA
147aDepartamento de Física, Pontificia Universidad Católica de Chile, Santiago, Chile
147bDepartamento de Física, Universidad T´ecnica Federico Santa María, Valparaíso, Chile
148Department of Physics, University of Washington, Seattle, Washington, USA
149Department of Physics and Astronomy, University of Sheffield, Sheffield, United Kingdom
150Department of Physics, Shinshu University, Nagano, Japan ç
p
g
140bDepartamento de Física, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
140cDepartamento de Física, Universidade de Coimbra, Coimbra, Portugal
140dCentro de Física Nuclear da Universidade de Lisboa, Lisboa, Portugal
140eDepartamento de Física, Universidade do Minho, Braga, Portugal
140fUniversidad de Granada, Granada (Spain), Spain
140gDep Física and CEFITEC of Faculdade de Ciências e Tecnologia,
Universidade Nova de Lisboa, Caparica, Portugal
141Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic Universidade Nova de Lisboa, Caparica, Portuga Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic
142Czech Technical University in Prague, Prague, Czech Republic
143 143Charles University, Faculty of Mathematics and Physics, Prague, Czech Republic
144Particle Physics Department, Rutherford Appleton Laboratory, Didcot, United Kingdom
145 145IRFU, CEA, Universit´e Paris-Saclay, Gif-sur-Yvette, France
146 146Santa Cruz Institute for Particle Physics, University of California Santa Cruz Moscow, Russia 114Fakultät für Physik, Ludwig-Maximilians-Universität München, München, Germany
115 Fakultät für Physik, Ludwig-Maximilians-Universi
5 anck-Institut für Physik (Werner-Heisenberg-Institut), München, Germany
116 115Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), München, Germany
116 116Nagasaki Institute of Applied Science, Nagasaki, Japan g
f
pp
g
p
117Graduate School of Science and Kobayashi-Maskawa Institute, Nagoya University, Nagoya, Jap
118 raduate School of Science and Kobayashi-Maskawa Institute, Nagoya University, Nagoya, Japan
partment of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico, USA
stitute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef, 118Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico, US
119Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhe 032007-33 032007-33 G. AAD et al. PHYS. REV. D 100, 032007 (2019) 106Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan, USA
107B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk, Belarus
108Research Institute for Nuclear Problems of Byelorussian State University, Minsk, Belarus
109Group of Particle Physics, University of Montreal, Montreal, Quebec, Canada
110P N Lebedev Physical Institute of the Russian Academy of Sciences Moscow Russia Institute for Theoretical and Experimental Physics of the National Research Centre Kurchatov Institute, University of Oklahoma, Norman, Oklahoma, USA 129Department of Physics, Oklahoma State University, Stillwater, Oklahoma, USA
130 130Palacký University, RCPTM, Joint Laboratory of Optics, Olomouc, Czech Republic
131 131Center for High Energy Physics, University of Oregon, Eugene, Oregon, USA
132 133Graduate School of Science, Osaka University, Osaka, Japan
134 134Department of Physics, University of Oslo, Oslo, Norway 135Department of Physics, Oxford University, Oxford, United Kingdom p
f
y
,
f
y,
f
,
g
136LPNHE, Sorbonne Universit´e, Paris Diderot Sorbonne Paris Cit´e, CNRS/IN2P3, Paris, France
137Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
138Konstantinov Nuclear Physics Institute of National Research Centre “Kurchatov Institute”, 137Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
138Konstantinov Nuclear Physics Institute of National Research Centre “Kurchatov Institute”, Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
138Konstantinov Nuclear Physics Institute of National Research Centre “Kurchatov Institute”, 138Konstantinov Nuclear Physics Institute of National Research Centre “Kurchatov Institute”, Moscow, Russia ,
112National Research Nuclear University MEPhI, Moscow, Russia National Research Nuclear University MEPhI, Mosc 113D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, 113D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University,
Moscow Russia 13D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University,
Moscow, Russia Santa Cruz, California, USA 147aDepartamento de Física, Pontificia Universidad Católica de Chile, Santiago, Chile
147bDepartamento de Física, Universidad T´ecnica Federico Santa María, Valparaíso, Chile
148Department of Physics, University of Washington, Seattle, Washington, USA
149Department of Physics and Astronomy, University of Sheffield, Sheffield, United Kingdom
150Department of Physics, Shinshu University, Nagano, Japan 148Department of Physics, University of Washington, Seattle, Washington, USA
149Department of Physics and Astronomy, University of Sheffield, Sheffield, United Kingdom
150Department of Physics, Shinshu University, Nagano, Japan Nijmegen, Netherlands j
g
120Nikhef National Institute for Subatomic Physics and University of Amsterdam, Amsterdam, Netherlan
121 f
f
y
y f
121Department of Physics, Northern Illinois University, DeKalb, Illinois, USA 121Department of Physics, Northern Illinois University, DeKalb, Illinois, USA
122 122bNovosibirsk State University Novosibirsk, Russia 123Institute for High Energy Physics of the National Research Centre Kurchatov Institute, Protvino, R
124 124Department of Physics, New York University, New York, New York, USA
125 125Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo, Japan
126 125Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo, Japan
126 26The Ohio State University, Columbus, Ohio, USA 127Faculty of Science, Okayama University, Okayama, Japan
128 culty of Science, Okayama University, Okayama, Ja 128Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, Oklahoma, USA 032007-34 032007-34 PHYS. REV. D 100, 032007 (2019) SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … f eAlso at TRIUMF, Vancouver, British Columbia, Canada. f fAlso at Department of Physics and Astronomy, University of Louisville, Louisville, Kentucky, USA gAlso at Physics Department, An-Najah National University, Nablus, Palestine. h hAlso at Department of Physics, California State University, Fresno, California, USA. i iAlso at Department of Physics, University of Fribourg, Fribourg, Switzerland. j jAlso at Physics Dept, University of South Africa, Pretoria, South Africa. k lAlso at Tomsk State University, Tomsk, and Moscow Institute of Physics and Technology State University, Dolgoprudny, Russia. lAlso at Tomsk State University, Tomsk, and Moscow Institute of Physics and Technology State mAlso at The Collaborative Innovation Center of Quantum Matter (CICQM), Beijing, China. nAlso at Departamento de Física, Instituto Superior T´ecnico, Universidade de Lisboa, Lisboa, Portuga oAlso at Universita di Napoli Parthenope, Napoli, Italy. oAlso at Universita di Napoli Parthenope, Napoli, Italy. pAlso at Institute of Particle Physics (IPP), Canada y
qAlso at Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg, Russia. qAlso at Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg, Russia. qAlso at Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg, Russia. rAlso at Department of Financial and Management Engineering, University of the Aegean, Chios, Gr p
g
g
g,
y
g
,
,
Centre for High Performance Computing, CSIR Campus, Rosebank, Cape Town, South Africa. sAlso at Centre for High Performance Computing, CSIR Campus, Rosebank, Cape Town,
t tAlso at Department of Physics, California State University, East Bay, California, USA. tAlso at Department of Physics, California State University, East Bay, California, USA. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Javakhishvili Tbilisi State University, Tbilisi, Georgia
159bHigh Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia
160Department of Physics, Technion, Israel Institute of Technology, Haifa, Israel
161Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel
162Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
163International Center for Elementary Particle Physics and Department of Physics,
University of Tokyo, Tokyo, Japan
164Graduate School of Science and Technology, Tokyo Metropolitan University, Tokyo, Japan
165Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
166Tomsk State University, Tomsk, Russia
167Department of Physics, University of Toronto, Toronto, Ontario, Canada
168aTRIUMF, Vancouver, British Columbia, Canada
168bDepartment of Physics and Astronomy, York University, Toronto, Ontario, Canada
169Division of Physics and Tomonaga Center for the History of the Universe,
Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
170Department of Physics and Astronomy, Tufts University, Medford, Massachusetts, USA
171Department of Physics and Astronomy, University of California Irvine, Irvine, California, USA
172Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden
173Department of Physics, University of Illinois, Urbana, Illinois, USA
174Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia—CSIC, Valencia, Spain
175Department of Physics, University of British Columbia, Vancouver, British Columbia, Canada
176Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia, Canada
177Fakultät für Physik und Astronomie, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
178Department of Physics, University of Warwick, Coventry, United Kingdom
179Waseda University, Tokyo, Japan
180Department of Particle Physics, Weizmann Institute of Science, Rehovot, Israel
181Department of Physics, University of Wisconsin, Madison, Wisconsin, USA
182Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik,
Bergische Universität Wuppertal, Wuppertal, Germany
183Department of Physics, Yale University, New Haven, Connecticut, USA
184Yerevan Physics Institute, Yerevan, Armenia 8aTRIUMF, Vancouver, British Columbia, Canada 79Waseda University, Tokyo, Japan 180Department of Particle Physics, Weizmann Institute of Science, Rehovot, Israel
181 181Department of Physics, University of Wisconsin, Madison, Wisconsin, USA
182 182Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik, Bergische Universität Wuppertal, Wuppertal, Germany Yale University, New Haven, Connecticut, USA of Physics, Yale University, New Haven, Connec
84 ment of Physics, Yale University, New Haven, Connecticut, USA
184 4Yerevan Physics Institute, Yerevan, Armenia aDeceased. b bAlso at Department of Physics, King’s College London, London, United Kingdom. c cAlso at Istanbul University, Dept. of Physics, Istanbul, Turkey. d cAlso at Istanbul University, Dept. of Physics, Istanbul, Turkey. d dAlso at Instituto de Fisica Teorica, IFT-UAM/CSIC, Madrid, Spai eAlso at TRIUMF, Vancouver, British Columbia, Canada. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … EARCH FOR ELECTROWEAK DIBOSON PRODUCTION … 151Department Physik, Universität Siegen, Siegen, Germany
152Department of Physics, Simon Fraser University, Burnaby, British Columbia, Canada
153SLAC National Accelerator Laboratory, Stanford, California, USA
154Physics Department, Royal Institute of Technology, Stockholm, Sweden
155Departments of Physics and Astronomy, Stony Brook University, Stony Brook, New York, USA
156Department of Physics and Astronomy, University of Sussex, Brighton, United Kingdom
157School of Physics, University of Sydney, Sydney, Australia
158Institute of Physics, Academia Sinica, Taipei, Taiwan
159aE. Andronikashvili Institute of Physics, Iv. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Javakhishvili Tbilisi State University, Tbilisi, Georgia
159bHigh Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia
160Department of Physics, Technion, Israel Institute of Technology, Haifa, Israel
161Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel
162Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
163International Center for Elementary Particle Physics and Department of Physics,
University of Tokyo, Tokyo, Japan
164Graduate School of Science and Technology, Tokyo Metropolitan University, Tokyo, Japan
165Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
166Tomsk State University, Tomsk, Russia
167Department of Physics, University of Toronto, Toronto, Ontario, Canada
168aTRIUMF, Vancouver, British Columbia, Canada
168bDepartment of Physics and Astronomy, York University, Toronto, Ontario, Canada
169Division of Physics and Tomonaga Center for the History of the Universe,
Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
170Department of Physics and Astronomy, Tufts University, Medford, Massachusetts, USA
171Department of Physics and Astronomy, University of California Irvine, Irvine, California, USA
172Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden
173Department of Physics, University of Illinois, Urbana, Illinois, USA
174Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia—CSIC, Valencia, Spain
175Department of Physics, University of British Columbia, Vancouver, British Columbia, Canada
176Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia, Canada
177Fakultät für Physik und Astronomie, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
178Department of Physics, University of Warwick, Coventry, United Kingdom
179Waseda University, Tokyo, Japan
180Department of Particle Physics, Weizmann Institute of Science, Rehovot, Israel
181Department of Physics, University of Wisconsin, Madison, Wisconsin, USA
182Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik,
Bergische Universität Wuppertal, Wuppertal, Germany
183Department of Physics, Yale University, New Haven, Connecticut, USA
184Yerevan Physics Institute, Yerevan, Armenia 151Department Physik, Universität Siegen, Siegen, Germany
152Department of Physics, Simon Fraser University, Burnaby, British Columbia, Canada
153SLAC National Accelerator Laboratory, Stanford, California, USA
154Physics Department, Royal Institute of Technology, Stockholm, Sweden
155Departments of Physics and Astronomy, Stony Brook University, Stony Brook, New York, USA
156Department of Physics and Astronomy, University of Sussex, Brighton, United Kingdom
157School of Physics, University of Sydney, Sydney, Australia
158Institute of Physics, Academia Sinica, Taipei, Taiwan
159aE. Andronikashvili Institute of Physics, Iv. SEARCH FOR ELECTROWEAK DIBOSON PRODUCTION … Javakhishvili Tbilisi State University, Tbilisi, Georgia
159bHigh Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia
160Department of Physics, Technion, Israel Institute of Technology, Haifa, Israel
161Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel
162Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
163International Center for Elementary Particle Physics and Department of Physics,
University of Tokyo, Tokyo, Japan
164Graduate School of Science and Technology, Tokyo Metropolitan University, Tokyo, Japan
165Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
166Tomsk State University, Tomsk, Russia
167Department of Physics, University of Toronto, Toronto, Ontario, Canada
168aTRIUMF, Vancouver, British Columbia, Canada
168bDepartment of Physics and Astronomy, York University, Toronto, Ontario, Canada
169Division of Physics and Tomonaga Center for the History of the Universe,
Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
170Department of Physics and Astronomy, Tufts University, Medford, Massachusetts, USA
171Department of Physics and Astronomy, University of California Irvine, Irvine, California, USA
172Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden
173Department of Physics, University of Illinois, Urbana, Illinois, USA
174Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia—CSIC, Valencia, Spain
175Department of Physics, University of British Columbia, Vancouver, British Columbia, Canada
176Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia, Canada
177Fakultät für Physik und Astronomie, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
178Department of Physics, University of Warwick, Coventry, United Kingdom
179Waseda University, Tokyo, Japan
180Department of Particle Physics, Weizmann Institute of Science, Rehovot, Israel
181Department of Physics, University of Wisconsin, Madison, Wisconsin, USA
182Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik,
Bergische Universität Wuppertal, Wuppertal, Germany
183Department of Physics, Yale University, New Haven, Connecticut, USA
184Yerevan Physics Institute, Yerevan, Armenia 151Department Physik, Universität Siegen, Siegen, Germany
152Department of Physics, Simon Fraser University, Burnaby, British Columbia, Canada
153SLAC National Accelerator Laboratory, Stanford, California, USA
154Physics Department, Royal Institute of Technology, Stockholm, Sweden
155Departments of Physics and Astronomy, Stony Brook University, Stony Brook, New York, USA
156Department of Physics and Astronomy, University of Sussex, Brighton, United Kingdom
157School of Physics, University of Sydney, Sydney, Australia
158Institute of Physics, Academia Sinica, Taipei, Taiwan
159aE. Andronikashvili Institute of Physics, Iv. 032007-35 032007-35 PHYS. REV. D 100, 032007 (2019) G. AAD et al. uAlso at Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona, Spain. p
vAlso at Department of Physics, University of Michigan, Ann Arbor, Michigan, USA. vAlso at Department of Physics, University of Michigan, Ann Arbor, Michigan, USA. p
y
y
g
g
wAlso at LAL, Universit´e Paris-Sud, CNRS/IN2P3, Universit´e Paris-Saclay, Orsay, France. xAlso at Graduate School of Science, Osaka University, Osaka, Japan. xAlso at Graduate School of Science, Osaka University, Osaka, Japan. Also at Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany. yAlso at Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany. zAlso at Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan. aa zAlso at Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan. aaAlso at Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef, Nijmege
Netherlands. aaAlso at Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef, Nijmegen,
Netherlands. bb bbAlso at Institute of Theoretical Physics, Ilia State University, Tbilisi, Georgia. bbAlso at Institute of Theoretical Physics, Ilia State University, Tbilisi, Georgia. bbAlso at Institute of Theoretical Physics, Ilia State University, Tbilisi, Georgia. ccAlso at CERN, Geneva, Switzerland. dd ddAlso at Department of Physics, Stanford University, Stanford, California, USA. ddAlso at Department of Physics, Stanford University, Stanford, California, USA. so at Department of Physics, Stanford University, S eeAlso at Manhattan College, New York, New York, USA. eeAlso at Manhattan College, New York, New York, USA. ff ffAlso at Joint Institute for Nuclear Research, Dubna, Russia. ffAlso at Joint Institute for Nuclear Research, Dubna, Russia. gAlso at Hellenic Open University, Patras, Greece. h p
y
hhAlso at The City College of New York, New York, New York, USA. ii hhAlso at The City College of New York, New York, New York, USA. ii hAlso at The City College of New York, New York
ii iiAlso at Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China. jj iiAlso at Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, Ch
jj jjAlso at Department of Physics, California State University, Sacramento, USA. kk jjAlso at Department of Physics, California State University, Sacramento, USA. kk kkAlso at Moscow Institute of Physics and Technology State University, Dolgoprudny, Russia. 032007-35 ll kkAlso at Moscow Institute of Physics and Technology State University, Dolgopru
ll llAlso at D´epartement de Physique Nucl´eaire et Corpusculaire, Universit´e de Gen`eve, Gen`eve, Swit llAlso at D´epartement de Physique Nucl´eaire et Corpusculaire, Universit´e de Gen`eve, Gen`eve, Switzerlan Department of Physics and Astronomy, University o nnAlso at Louisiana Tech University, Ruston, Louisiana, USA. nnAlso at Louisiana Tech University, Ruston, Louisiana, USA. y
ooAlso at School of Physics, Sun Yat-sen University, Guangzhou, China. ooAlso at School of Physics, Sun Yat-sen University, Guangzhou, China. r Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Sofia, Bulg Also at Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Scie ppAlso at Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Aca at Institute for Nuclear Research and Nuclear Energ qqAlso at Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia. at Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia. qqAlso at Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia. rrAlso at Department of Applied Physics and Astronomy, University of Sharjah, Sharjah, United Arab rrAlso at Department of Applied Physics and Astronomy, University of Sharjah, Sharjah, U p
pp
y
y,
y
j
,
j
,
ssAlso at Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany. p
pp
y
y
y
j
j
ssAlso at Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany. tt ttAlso at CPPM, Aix-Marseille Universit´e, CNRS/IN2P3, Marseille, France. ttAlso at CPPM, Aix-Marseille Universit´e, CNRS/IN2P3, Marseille, France uuAlso at National Research Nuclear University MEPhI, Moscow, Russia. uuAlso at National Research Nuclear University MEPhI, Moscow, Russia. Also at National Research Nuclear University MEPhI, Moscow, Russia. vvAlso at Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Budapest, Hungary. y
e for Particle and Nuclear Physics, Wigner Research Centre for Physics, Budapest, Hungary. vvAlso at Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Budapest, H vvAlso at Institute for Particle and Nuclear Physics, Wigner Research Ce wwAlso at Giresun University, Faculty of Engineering, Giresun, Turkey. wwAlso at Giresun University, Faculty of Engineering, Giresun, Turkey. xxAlso at Institute of Physics, Academia Sinica, Taipei, Taiwan. xxAlso at Institute of Physics, Academia Sinica, Taipei, Taiwan. 032007-36
|
https://openalex.org/W2169327636
|
https://www.scielo.br/j/jbchs/a/4QbCTjPQtRVtn66BvJXwYff/?lang=en&format=pdf
|
English
| null |
Effect of confinement of anionic organic ultraviolet ray absorbers into two-dimensional zinc hydroxide nitrate galleries
|
Journal of the Brazilian Chemical Society
| 2,011
|
cc-by
| 5,719
|
Ana Cristina T. Cursino,a Antonio Salvio Mangrich,b José Eduardo F. da Costa
Gardolinski,c Ney Mattosod and Fernando Wypych*,a Ana Cristina T. Cursino,a Antonio Salvio Mangrich,b José Eduardo F. da Costa
Gardolinski,c Ney Mattosod and Fernando Wypych*,a aCEPESQ - Research Centre of Applied Chemistry, Department of Chemistry,
bLABPAM - Laboratory of Environmental Projects and Processes, Department of Chemistry,
cLAMIR - Laboratory for Analysis of Minerals and Rocks, Department of Geology and
dDepartment of Physics, Federal University of Paraná, PO Box 19081,
81531-980 Curitiba-PR, Brazil Espécies aniônicas absorvedoras de radiação ultravioleta (UV) (4-metoxibenzoato,
N-acetilantranilato, 4-metoxicinamato e 4,4'-diamino-2,2'-estilbenodissulfonato) foram intercaladas
em hidroxinitrato de zinco pelo método de co-precipitação ou reação de troca aniônica topotática. A intercalação foi confirmada por difratometria de raios X de pó (XRPD), espectroscopia na
região do infravermelho com transformada de Fourier (FTIR), análise térmica (TGA/DTA),
microscopia eletrônica de varredura (SEM), difração de elétrons em área selecionada (SAED),
análise elementar e espectroscopia eletrônica na região do ultravioleta-visível (UV-Vis). Na reação
de co-precipitação uma intercalação completa foi observada, enquanto na reação de troca aniônica
os íons nitrato só foram parcialmente substituídos pelos ânions orgânicos. Após a intercalação,
a capacidade de absorção de radiação UV foi similar à dos sais e ácidos sólidos, sendo o efeito
atribuído ao confinamento das espécies aniônicas na galeria bidimensional da matriz hospedeira. Essa observação abre novas oportunidades para o uso de matrizes lamelares alternativas para a
imobilização de ânions, na formulação de protetores solares. Anionic ultraviolet (UV) ray absorbers (4-methoxybenzoate, N-acetylanthranilate,
4-methoxycinnamate and 4,4'-diamino-2,2'-stilbenedisulfonate) were intercalated into zinc
hydroxide nitrate, either by direct alkaline co-precipitation or topotactic exchange reactions. The
intercalation was confirmed by X-ray powder diffractometry (XRPD), Fourier transform infrared
spectroscopy (FTIR), thermal analysis (TGA/DTA), scanning electron microscopy (SEM), selected
area electron diffraction (SAED), elemental analysis and ultraviolet visible (UV-Vis) spectroscopy. In the co-precipitation reactions full intercalation was achieved, while during the exchange reactions
nitrate anions were not completely replaced by the organic anions. After the intercalation, the UV
absorption capacity was similar to that of the solid salts and acids, the effect being attributed to
the confinement of the anionic species in the host two-dimensional gallery. This observation opens
new opportunities for the use of organic anions immobilized in alternative layered matrixes for
the formulation of sunscreens. Keywords: zinc hydroxide nitrate, UV ray absorbers, sunscreens, layered materials
intercalation *e-mail: wypych@ufpr.br J. Braz. Chem. Soc., Vol. 22, No. 6, 1183-1191, 2011.
Printed in Brazil - ©2011 Sociedade Brasileira de Química
0103 - 5053 $6.00+0.00 J. Braz. Chem. Soc., Vol. 22, No. 6, 1183-1191, 2011. Printed in Brazil - ©2011 Sociedade Brasileira de Química
0103 - 5053 $6.00+0.00 Article Synthesis of zinc hydroxide nitrate The synthesis of zinc hydroxide nitrate (ZHN) was
carried out following a procedure described elsewhere.17,18 In short, it was prepared by the slow addition of an
aqueous NaOH solution (1 mol L−1) into 70 mL of aqueous
solution containing 17.5 mmol of Zn(NO3)2∙6H2O, under
magnetic stirring, with the final pH adjusted to around 6.5. The solid was separated by centrifuging at 4000 rpm for
5 min, followed by extensive washing with distilled water
(5 times). The final white solid was dried under vacuum at
60 °C for 24 h. The prepared ZHN was used as a matrix
for the intercalation of several organic UV ray absorber
anions, whose acids are shown in Figure 1. Even though the use of UV ray absorber molecules,
due to their high affinity for the stratum corneum, is
very widespread, they can be easily absorbed by the
body, leading to phototoxic and allergic reactions.6-8 To
prevent the direct contact of such molecules with human
tissues, they can be intercalated into layered structures,
such as layered hydroxide salts (LHSs)9 and other layered
materials.10-12 Exchange reaction An intercalation compound with 4-methoxybenzoate
was prepared by the slow addition of 50 mL of an aqueous
solution of NaOH (1 mol L−1) to 70 mL of a suspension
containing 4.7 mmol of 4-methoxybenzoic acid (Figure 1a)
in decarbonated water, to obtain a solution of sodium
4-methoxybenzoate salt. To this solution, ZHN (2 mmol)
was added and the suspension was magnetically stirred at
60 °C for 4 days, before being centrifuged and extensively
washed with distilled water (4 times). The final white solid
(ZHN-MB) was dried under vacuum at 60 °C for 24 h. The
same procedure was followed to synthesize the product
with N-acetylanthranilic acid (Figure 1b, ZHN-NAA). The structure of LHSs is derived from that of a generic
layered hydroxide (M(OH)2), where a fraction of the
hydroxyl sites are substituted by other anions or by water
molecules, resulting in a structure with positively charged
layers that are electrically balanced by intercalated anions. Their general formula is M2+(OH)2−x(An−)x/n·yH2O, where
M2+ is a metal cation (Mg, Ni, Zn, Ca, Cd, Co and Cu) and
A is the n− charged anion, called the counter-ion (Cl−, NO3
−,
SO4
2− and H3CCOO−).13-16 Due to the structural characteristics
of LHSs, various kinds of anions can be intercalated, from
simple monoatomic species to complex molecules. The main goal of this work is to further study the
intercalation of UV radiation absorbers into LHSs. This
could possibly give rise to a new generation of sunscreens
that could significantly reduce the absorption of the active
molecules by the human skin, avoiding the cause of many
allergic reactions and also slowing their photodegradation. Introduction their frequent and long-term use, special attention has been
devoted to the efficiency and safety of these formulations.1 Health problems related to the exposure to solar
ultraviolet (UV) radiation can be minimized by the use of
sunscreens and other cosmetic filters. These products are
regularly used by millions around the globe. Because of UV ray absorbing organic molecules are widely
employed as active ingredients of sunscreens. Among such
substances are anthranilates and cinnamates.2 Although
there are a large number of anthranilates (also known as
ortho-aminobenzoates), only two of them are commonly
found in commercial products: homomethyl-N-acetyl- Effect of Confinement of Anionic Organic Ultraviolet Ray Absorbers 1184 J. Braz. Chem. Soc. Experimental anthranilate and methyl-anthranilate. As the UVA ray
absorption of these compounds is low, they are usually
used together with other UV absorbers. These compounds
present good stability and solubility in topical preparations,
with absorption maxima around 336 nm for the ortho
and 300 nm for the para molecules.3 On the other hand,
the cinnamates constitute a larger group of compounds,
seventeen of them having been approved as sunscreens in
Europe and four in the United States. The cinnamates are
insoluble in water but highly soluble in alcohol, acetone
and benzene. They act as absorbers in the UVB region,
with maxima around 300 nm.4,5 Characterization X-ray powder diffraction (XRPD) patterns were
recorded with a Shimadzu XDR-6000 instrument using
CuKα radiation (λ = 1.5418 Å) in Bragg-Brentano
geometry, with a dwell time of 1° min−1. The samples
were placed and oriented by hand by pressing on neutral
glass sample holders. The FTIR spectra were recorded with a Bio-
Rad FTS 3500GX and a Bomem Michelson MB100
spectrophotometers, using approximately 1% sample in
100 mg of spectroscopic grade KBr. The pellets were
pressed at 10 ton. The measurements were performed in
transmission mode with accumulation of 32 scans and
recorded with a nominal resolution of 2 cm−1. Figure 2. XRPD patterns of 4,4'-diamino-2,2'-stilbenedisulfonic acid
(a), 4',4-diamino-2,2'-stilbenedisulfonic acid sodium salt (b), ZHN (c)
and ZHN-DSD (d). The product obtained from the alkaline precipitation
shows the formation of a crystalline phase of the zinc
hydroxide nitrate (Zn5(OH)8(NO3)2·2H2O = ZHN),
identified by the JCPDS file number 24-1460.19 The
diffraction pattern shows an intense reflection due to the
(200) plane of the monoclinic structure, with a basal spacing
of 9.77 Å (Figure 2c). Thermal analyses (thermogravimetry-TGA and
differential thermal analysis-DTA) were performed in
150 µL alumina crucibles with a Mettler-Toledo TG/
SDTA 851e Thermoanalyser under a 50 mL min−1 oxygen
flow, at a heating rate of 10 °C min−1, in the range of
30-1000 °C.l For the direct synthesis from 4,4'-diamino-2,2'-
stilbenedisulfonic acid in the presence of zinc nitrate through
alkaline co-precipitation, the basal spacing of the product
(ZHN-DSD) was measured as 15.48 Å (Figure 2d). This
indicates the presence of the organic anion between the
inorganic layers of the matrix, with a basal expansion of 5.71 Å
from the original compound. The preservation of the layered
structure of the matrix is confirmed by the presence of the
basal reflections, which are uniformly distributed between 5°
and 35° (in 2θ). In the region of 16° (in 2θ), the small peak
indicated by an “*” is of one unknown phase, but it is not
attributed to the 4,4'-diamino-2,2'-stilbenedisulfonic acid. The diffuse reflectance ultraviolet-visible (DRUV-
VIS) spectra were obtained at room temperature in the
region of 240-800 nm, at intervals of 0.5 nm, with a
Shimadzu UV-2401PC spectrophotometer equipped with
a Model 240-52454-01 integration sphere. Scanning electron microscopy (SEM) analyses of
the samples were carried out (after metallization with
gold) with a JEOL JSM 6360 LV microscope operating
at 15 kV. Synthesis by co-precipitation As some organic anions do not have the sufficient
thermodynamic driving forces to displace the intercalated
nitrate anions from the ZHN structure, new attempts Figure 1. Organic UV ray absorbing molecules used in the intercalation reactions with ZHN. Cursino et al. 1185 Vol. 22, No. 6, 2011 Results and Discussion were made to produce these compounds by direct
co-precipitation. The intercalation compound with
4-methoxycinnamate (Figure 1c) was prepared by
dissolving 2.5 mmol of 4-methoxycinnamic acid in
20 mL of an aqueous solution of NaOH (0.4 mol L−1). To this, 20 mL of a solution containing 7.5 mmol of
Zn(NO3)2·6H2O was slowly added and the final pH
was adjusted to around 7 by the addition of a NaOH
(0.4 mol L−1) solution. The suspension was magnetically
stirred at room temperature for 3 days, before being
centrifuged and washed 5 times with distilled water. The
final white solid (ZHN-MC) was dried under vacuum
at 60 °C for 24 h. The same procedure was followed
to synthesize the product with 4,4'-diamino-2,2'-
stilbenedisulfonic acid (Figure 1d), denoted ZHN-DSD. The XRPD patterns of ZHN and the compound
prepared by co-precipitation with 4,4'-diamino-2,2'-
stilbenedisulfonic acid are shown in Figure 2. Figure 2. XRPD patterns of 4,4'-diamino-2,2'-stilbenedisulfonic acid
(a), 4',4-diamino-2,2'-stilbenedisulfonic acid sodium salt (b), ZHN (c)
and ZHN-DSD (d). Characterization Selected area electron diffraction (SAED)
measurements were performed with a JEOL JEM
1200 EX-II transmission electron microscope (TEM)
operating at 80 kV for pure HZN and 50 kV for the
compounds obtained by co-precipitation. Calibration
of the electron diffraction to SAED measurements was
carried out using an Au sample as reference. The FTIR spectra of the same compounds are shown
in Figure 3. The FTIR spectrum of the ZHN (Figure 3c) presents an
intense band at 1384 cm−1, characteristic of the nitrate ion with Effect of Confinement of Anionic Organic Ultraviolet Ray Absorbers J. Braz. Chem. Soc. 1186 Figure 3. FTIR spectra of 4,4'-diamino-2,2'-stilbenedisulfonic acid (a),
4',4-diamino-2,2'-stilbenedisulfonic acid sodium salt (b), ZHN (c) and
ZHN-DSD (d). f(KM) = (1 − R)2 / 2R = k/s, where R is the reflectance, k is
the absorption coefficient and s is the dispersion coefficient.23
Assuming that the dispersion coefficient varies minimally as
a function of the wavelength, the reemission function areas
and the absorption function areas of the spectra should be
very near each other. Figure 4. DRUV-VIS spectra of ZHN (a), 4,4'-diamino-2,2'-
stilbenedisulfonic acid (b), 4',4-diamino-2,2'-stilbenedisulfonic sodium
salt (c), ZHN-DSD (d) and ZHN-DSD after 2 h stirring in water (e). Figure 3. FTIR spectra of 4,4'-diamino-2,2'-stilbenedisulfonic acid (a),
4',4-diamino-2,2'-stilbenedisulfonic acid sodium salt (b), ZHN (c) and
ZHN-DSD (d). D3h symmetry (ν3 mode)18. A broad band around 3500 cm−1 is
also seen, attributed to the vibration of the hydroxyl groups,
which have multiple hydrogen bonds with physisorbed/
intercalated water molecules. A narrow band present at
3575 cm−1 is also attributed to hydroxyl groups, but in this case
from the crystal lattice, with a well defined vibration energy.20 Figure 4. DRUV-VIS spectra of ZHN (a), 4,4'-diamino-2,2'-
stilbenedisulfonic acid (b), 4',4-diamino-2,2'-stilbenedisulfonic sodium
salt (c), ZHN-DSD (d) and ZHN-DSD after 2 h stirring in water (e). The FTIR spectrum of the 4,4'-diamino-2,2'-
stilbenedisulfonic acid (Figure 3a) presents a band
between 3140 and 2920 cm−1 that is attributed to the
axial deformation of aromatic N−H and C−H aliphatic
groups. Normally the symmetric and asymmetric axial
deformations of the S=O groups are visible around 1350-
1342 cm−1 and 1165-1150 cm−1, respectively. Characterization 1187 precursor ZHN is characterized by tabular particles with
well defined corners and a wide size distribution, in
accordance to what has already been reported for similar
compounds.16 The co-precipitated ZHN-DSD compound
was also characterized by tabular particles with well defined
corners, these however being much larger than those of the
ZHN and very fragmented, due to the magnetic stirring. The stability of the ZHN-DSD product was tested
by stirring in water for 2 h. After this treatment, the
absorption in the ultraviolet region was virtually unchanged
(Figure 4e). In addition, the XRPD pattern of this product
(not shown) showed no changes in relation to the original
product. Thermal analysis (TGA/DTA) results from ZHN (not
shown) reveal a complex decomposition profile with a
series of endothermic events around 200 °C (129, 163,
214 and 262 °C), attributed to loss of water, both adsorbed
and structural, which comprises 6% of the total mass up
to 131 °C. Between 131 and 552 °C a mass loss of 27%
occurs, attributed to the matrix dehydroxylation along with
nitrate decomposition.26 The mass losses are consistent
with the formula Zn5(OH)8(NO3)2·1.74H2O, close to the
theoretical formula. Figure 7 presents the XRPD patterns of the ZHN
derivatives with 4-methoxybenzoate, ZHN-MB
(Figure 7b), 4-methoxycinnamate, ZHN-MC (Figure 7c)
and N-acetylanthranilate, ZHN-NAA (Figure 7d). y
g
The basal spacing of the ZHN-MB and ZHN-MC
compounds increased from the original 9.77 Å of the
pristine ZHN to 18.67 and 20.13 Å, respectively. This
strongly indicates the substitution of the originally
intercalated nitrate anion by the corresponding organic
anions employed. It can also be seen that these products
are possibly contaminated with phases presenting various
degrees of hydration or formation of stage intermediate
phase, characterized by low intensity peaks at 26.5 and
26.9 Å for ZHN-MC and ZHN-MB, respectively. The
X-ray diffraction patterns of the ZHN-NAA compound
(Figure 7d) show no clear distinction in the basal distances
from the original ZHN, suggesting that the organic
anion was not intercalated. This is probably due to the
incompatibility between the positions of the negative
charges in the N-acetylanthranilate and the positive charges
in the ZHN structure. However, no diffraction peaks due to
the free acid or its sodium salt could be detected. TGA/DTA measurements were performed to estimate
the composition of the intercalation compounds (Figure 5). Figure 5. TGA/DTA curves for the ZHN-DSD compound. Characterization However, it
was not possible to identify these bands because such values
are due to the anhydrous form of the acid, which promptly
hydrates to a hydronium-sulfonate, thus giving rise to bands
around 1230-1120 cm−1.21 These hydrated form bands are
present in the acid at 1200 cm−1 and also in its sodium salt
(Figure 3b) and in the ZHN-DSD compound (Figure 3d). The axial deformation bands of the aromatic C=C groups
around 1613 and 1482 cm−1 seen in the acid, its sodium salt
and, most importantly, in the ZHN-DSD compound, further
confirm the intercalation of the organic anion. The yellowish 4,4'-diamino-2,2'-stilbenedisulfonic
acid has an absorption maximum in the region around
250-354 nm (Figure 4b), covering the entire UVB region
and part of the UVA region. Its orange colored sodium salt
absorbs in the region around 240-379 nm, covering the
UVC to UVA regions (Figure 4c). The ZHN-DSD product has a light beige color, which
can be considered esthetically more pleasing and thus more
usable than the strong-colored free acid and its sodium
salt. It has a significant absorption in the whole ultraviolet
region, from UVA to UVC (Figure 4d), slightly less intense
in the higher wavelengths than the free sodium salt due to
the dilution effect after intercalation into the ZHN layered
material. The organic molecule slightly increases its range
to absorb UV light, and this effect can be interpreted on
the basis of the spatial confinement of the anionic species
in the interlayer LHS space, lowering the symmetry of the
intercalated anion in comparison to the molecules in the
solid salt or acid, and also to supramolecular host-guest
interactions (electrostatic attraction, hydrogen bonding and
van der Waals forces).24,25 To study the behavior of the product in the ultraviolet-
visible region, DRUV-VIS spectroscopy was conducted
(Figure 4). The Kubelka-Munk function was applied to
the study of optically thick samples, where more than 50%
of the light is reflected and less than 20% is transmitted.22
The experimental reflectance spectra were converted by
the reemission function of Kubelka-Munk, defined as: Vol. 22, No. 6, 2011 Cursino et al. Characterization The FTIR spectra of 4-methoxycinnamate,
4-methoxybenzoate, N-acetylanthranilate and their ZHN
derivatives can be seen in Figure 8. Bands attributed to
vibrational modes from the N-acetylanthranilate anion are
present in the FTIR spectrum of the ZHN-NAA product
(Figure 8g). In this case, the bands at 1515 and 1415 cm−1
are attributed to the asymmetric and symmetric carboxylate
stretching modes. Between 2900 and 2850 cm−1, weak
bands from the axial deformation of methyl C−H bonds
are also present. In addition, the characteristic nitrate
band at 1384 cm−1 is still present. The presence of these
organic bands and the fact there was no change in the basal
spacing of the matrix suggests that the N-acetylanthranilate
molecules are adsorbed on the surface of the ZHN particles. Figure 5. TGA/DTA curves for the ZHN-DSD compound. The thermal analysis curves of ZHN-DSD show three
main thermal events. The first two correspond to the
removal of physisorbed/intercalated water molecules,
associated with two DTA peaks at 160 and 215 °C. The third
thermal event is attributed to the oxidation of organic matter
and dehydroxylation of the layered matrix, producing ZnO,
as attested by XRD (not shown). With this information, it
was possible to estimate the composition of the compounds
as being Zn5(OH)8(NO3)0.04(C14H12N2O6S2)0.98·0.84 H2O,
close to the stoichiometric value. The thermal stability
of ZHN-DSD is around 250 °C, under dynamic heat
conditions. For the ZHN-MB and ZHN-MC compounds, the
presence of the intercalated organic UV ray absorbing
anions can be attested by their FTIR spectra (Figures 8c
and 8e). Around 1540 and 1420 cm−1, bands attributed to
carboxylate asymmetric and symmetric stretching modes
are observed, as well as bands between 3070 and 2840 cm−1,
attributed to the axial deformation of C−H groups in
aromatic rings and methyl groups,27 alongside other bands Morphological analyses of the ZHN (Figure 6a) and
ZHN-DSD (Figure 6b) were performed by SEM. The Effect of Confinement of Anionic Organic Ultraviolet Ray Absorbers 1188 J. Braz. Chem. Soc. Figure 6. SEM images of ZHN (a) and ZHN-DSD (b). Figure 7. XRPD patterns of ZHN (a), ZHN-MB (b), ZHN-MC (c)
ZHN-NAA (d). Figure 6. SEM images of ZHN (a) and ZHN-DSD (b). Figure 8. FTIR spectra of ZHN (a), sodium methoxycinnamate (b),
ZHN-MC (c), sodium methoxybenzoate (d), ZHN-MB (e), sodium
N-acetylanthranilate (f) and ZHN-NAA (g). Figure 8. Characterization FTIR spectra of ZHN (a), sodium methoxycinnamate (b),
ZHN-MC (c), sodium methoxybenzoate (d), ZHN-MB (e), sodium
N-acetylanthranilate (f) and ZHN-NAA (g). Figure 6. SEM images of ZHN (a) and ZHN-DSD (b). Table 1. Wavenumbers (cm−1) of some vibrational modes in the
ZHN-MB and ZHN-MC compounds and the respective organic sodium salts Figure 7. XRPD patterns of ZHN (a), ZHN-MB (b), ZHN-MC (c) and
ZHN-NAA (d). Compound
COO−
(as)
COO−
(sym)
C=C(arom)
C−O−C(as) C−O−C(sym)
Na-MC
1554
1433
1512
1243
1033
ZHN-MC
1542
1423
1517
1259
1027
Na-MB
1596
1419
1541
1251
1029
ZHN-MB
1606
1417
1548
1259
1032
(as) = Asymmetric stretching; (sym) = symmetric stretching. of the organic matter (exothermic event around 400 °C). As discussed for the ZHN-DSD, the TGA/DTA analysis
allows us to estimate the formula of the compounds as
Zn5(OH)8(NO3)0.46(C10H9O3)1.54·3.4H2O for ZHN-MC and
Zn5(OH)8(NO3)0.48(C8H7O3)1.52·4.6H2O for ZHN-MB, where
not all the nitrate anions were replaced by the organic
anions. The adsorption of the N-acetylanthranilate anions
onto ZHN is further attested by the TGA/DTA results (not
shown), since they are clearly distinct from the thermal
profile of the original ZHN. Figure 7. XRPD patterns of ZHN (a), ZHN-MB (b), ZHN-MC (c) and
ZHN-NAA (d). The DRUV-VIS spectroscopic analysis of the
ZHN-NAA compound (Figure 9d) presented absorption
bands similar to those of the free acid (Figure 9c), its
sodium salt (Figure 9b) and also the ZHN (Figure 9a). presented in Table 1. Bands attributed to the inorganic
matrix are also present, like the broad signal between 3600
and 3350 cm−1, characteristic of lattice hydroxyl groups.i The thermal profiles of the ZHN-MB and ZHN-MC
compounds (not shown) are very similar, presenting
two major events, the first one attributed to water loss
(endothermic event around 150 °C) and the second one
attributed to the dehydroxylation of the matrix and burning However, in the UVA region, a shifted absorption
maximum not seen in any of the precursors can be
observed in the product. This is another indication that the
UV-absorbing organic molecules are adsorbed on the ZHN
particles outer surfaces. Cursino et al. 1189
Vol. 22, No. 6, 2011
Figure 9. DRUV-VIS spectra of: ZHN (a), sodium N-acetylanthranilate (b),
N-acetylanthranilic acid (c) and ZHN-NAA (d). Figure 10. DRUV-VIS spectra of: ZHN (a), sodium 4-methoxycinnamate
(b), ZHN-MC (c), sodium 4-methoxybenzoate (d) and ZHN-MB (e). 1189 Vol. 22, No. 6, 2011 Cursino et al. Figure 9. Characterization DRUV-VIS spectra of: ZHN (a), sodium N-acetylanthranilate (b),
N-acetylanthranilic acid (c) and ZHN-NAA (d). Figure 10. DRUV-VIS spectra of: ZHN (a), sodium 4-methoxycinnamate
(b), ZHN-MC (c), sodium 4-methoxybenzoate (d) and ZHN-MB (e). Figure 10. DRUV-VIS spectra of: ZHN (a), sodium 4-methoxycinnamate
(b), ZHN-MC (c), sodium 4-methoxybenzoate (d) and ZHN-MB (e). Figure 10. DRUV-VIS spectra of: ZHN (a), sodium 4-methoxycinnamate
(b), ZHN-MC (c), sodium 4-methoxybenzoate (d) and ZHN-MB (e). Figure 9. DRUV-VIS spectra of: ZHN (a), sodium N-acetylanthranilate (b),
N-acetylanthranilic acid (c) and ZHN-NAA (d). Figure 11. SEM images of: ZHN (a) ZHN-MC (b) and ZHN-NAA (c). The white-colored sodium 4-methoxybenzoate
presented an absorption maximum around 250-290 nm,
covering the UVC to the UVB regions, as seen from the
DRUV-VIS results (Figure 10d). After intercalation, the
ZHN-MB product, also white, presented one absorption
maximum around 253 nm (Figure 10e). Results from
the DRUV-VIS spectroscopy analysis of the ZHN-MC
compound (Figure 10c) presented one absorption maximum
around 297 nm, not absorbing in the visible region
(λ > 400 nm). This characteristic is possibly an advantage
to the cosmetics industry, where colored additives are
not always desired. In addition, this product absorbs in
a broad spectral range, including UVC and UVB regions
and a small part of the UVA region. This behavior is
closely related to the sodium 4-methoxycinnamate, with
an absorption range between 240 and 308 nm (Figure 10b),
but significantly different than the 4-methoxycinnamic acid
(not shown), with a maximum around 264-387 nm. As in the case of the ZHN-DSD compound, scanning
electron microscopy images of the products obtained
by co-precipitation (ZHN-MC) and exchange reaction
(ZHN-NAA) (Figures 11b and 11c) showed tabular
particles with larger size and wider size distribution than
those of ZHN (Figure 11a). The crystal growing process
can be attributed to dissolution and re-precipitation during
the exchange reaction. The SAED pattern of the compounds obtained by co-
precipitation confirmed that the basic structure is from
the ZHN and the only difference between the products
is the basal distance observed by XRD measurements Figure 11. SEM images of: ZHN (a) ZHN-MC (b) and ZHN-NAA (c). 1190 Effect of Confinement of Anionic Organic Ultraviolet Ray Absorbers
J. Braz. Chem. So Effect of Confinement of Anionic Organic Ultraviolet Ray Absorbers J. Braz. Chem. Soc. Figure 12. References 1. Wissing, S. A.; Müller, R. H.; Int. J. Pharm. 2002, 242, 373. 1. Wissing, S. A.; Müller, R. H.; Int. J. Pharm. 2002, 242, 373. 2. Urbach, F.; J. Photochem. Photobiol., B 2001, 64, 99. 2. Urbach, F.; J. Photochem. Photobiol., B 2001, 64, 99. 3. Agrapidis-Paloympes, L. E.; Nash, R. A.; Shaath, N. A.; J. Soc. Cosmet. Chem. 1987, 38, 209. 4. Costa, E. J.; Lacaz, E.; Med Cután Ibero-Latino Am. 2001, 29,
145. 5. Hoyo, C.; Vicente, M. A.; Rives, V.; Clay Miner. 2001, 36, 541. 6. Perioli, L.; Ambrogi, V.; Bertini, B.; Ricci, M.; Nocchetti, M.;
Latterini, L.; Rossi, C.; Eur. J. Pharm. Biopharm. 2006, 62,
185. Characterization SAED pattern of ZHN obtained at 80 kV and at room temperature (a), ZHN-DSD obtained at 50 kV and at room temperature (b) and ZHN-MC
obtained at 50 kV at −43 °C (c). The SAED pattern in (c) was obtained using a cooled specimen holder (Gatan model 636). Figure 12. SAED pattern of ZHN obtained at 80 kV and at room temperature (a), ZHN-DSD obtained at 50 kV and at room temperature (b) and ZHN-MC
obtained at 50 kV at −43 °C (c). The SAED pattern in (c) was obtained using a cooled specimen holder (Gatan model 636). (see Figures 2 and 7). Figure 12 shows the standard SAED
for the ZHN matrix and for the compounds obtained by co-
precipitation. The ZHN matrix presented good structural
stability to perform the analysis, as did the co-precipitated
sample with stilbenedisulfonate (ZHN-DSD), both of them
presenting large single crystals. In the case of the sample
co-precipitated with methoxycinnamate (ZHN-MC), the
crystals are too small, generating a standard polycrystal,
as shown in Figure 12c. In addition, the structural stability
of this sample is too low to be analyzed under normal
conditions. The analysis then needs to be carried out at
−43 °C with a low-energy electron beam. have interesting UV ray absorbing properties, sometimes
even enhancing the absorption range of their precursors. Further research on these compounds could be very fruitful
to the cosmetics industry, especially because zinc oxide is
generally recognized as safe (GRAS) and is widely used as
antiseptic and whitening pigment in cosmetic formulations. Acknowledgments We gratefully acknowledge the Brazilian Research
Agencies CNPq, CAPES and FINEP for their financial
support of this work. A. C. T. Cursino thanks CNPq for
the masters research grant. We also acknowledge the use of
the Electron Microscopy Center of the Federal University
of Paraná. The indexed spots for the ZHN correspond to the
non basal direction contributions, showing that the layer
stacking occurs along the [100] axis. This crystallographic
orientation is the same in all samples analyzed by SAED
and no changes were observed in the spacing perpendicular
to the layers. This shows that the stilbenedisulfonate and
methoxycinnamate anions, in the co-precipitation process,
are only intercalated between the layers, as observed by
XRD in Figures 2 and 7, preserving the layer as in the ZHN
structure. Probably the basal spacing of 20.13 Å obtained
for the sample co-precipitated with cinnamate reduces the
cohesion between the layers, causing their low stability
under the electron beam. Conclusion Layered zinc hydroxide nitrate was used as host for
organic UV ray absorbing anions. 4-Methoxycinnamate,
4-methoxybenzoate and 4,4' -diamino-2,2' -
stilbenedisulfonate ions were intercalated between the ZHN
layers, whereas the N-acetylanthranilate anion was mostly
likely adsorbed on the outer surfaces of the hydroxide salt
particles. The products were characterized by XRPD, FTIR,
TGA/DTA, DRUV-VIS spectroscopy, SEM and SAED. The results show that the organic-inorganic derivatives 7. Perioli, L.; Nocchetti, M.; Ambrogi, V.; Latterini, L.; Rossi, C.;
Costantino, U.; Microporous Mesoporous Mater. 2008, 107,
180; Costantino, U.; Ambrogi, V.; Nocchetti, M.; Perioli, L.;
Microporous Mesoporous Mater. 2008, 107, 149. Microporous Mesoporous Mater. 2008, 107, 149. 8. Rietschel, R. L.; Fowler, J. F.; Fischer, A. A.; Fisher’s Contact
Dermatitis, 6th ed., BC Decker Inc.: Ontario, 2008. Dermatitis, 6th ed., BC Decker Inc.: Ontario, 2008. 9. Cursino, A. C. T.; Gardolinski, J. E. F. C.; Wypych, F.; J. Colloid
Interface Sci. 2010, 347, 49. 10. Hoyo, C.; Appl. Clay Sci. 2007, 36, 103. Vol. 22, No. 6, 2011 1191 Cursino et al. 11. Feng, Y. J.; Li, D. Q.; Wang, Y.; Evans, D.G.; Duan, X.; Polym. Degrad. Stab. 2006, 91, 789. 20. Arizaga, G. C. G.; Mangrich, A. S. M.; Wypych, F.; J. Colloid
Interface Sci. 2008, 320, 238. 12. Rossi, C.; Schoubben, A.; Ricci, M.; Perioli, L.; Ambrogi, V.;
Latterini, L.; Aloisi, G. G.; Rossi, A.; Int. J. Pharm. 2005, 295, 47. 12. Rossi, C.; Schoubben, A.; Ricci, M.; Perioli, L.; Ambrogi, V.;
L
i i L Al i i G G R
i A
h
2005 295 47 21. Silverstein, R. M.; Webster, F. X.; Kiemle, D. J.; Spectrometric
Identification of Organic Compounds, 7th ed., J. Wiley & Sons:
Hoboken, USA, 2005. 13. Xue, M.; Chitrakar, R.; Sakane, K.; Ooi, K.; Kobayashi, S.;
Ohnishi, M.; Doi, A.; J. Solid State Chem. 2004, 177, 1624. 22. Kubelka, P.; Munk, F.; Z. Tech. Phys. 1931, 12, 593. 14. Nishizawa, H.; Yuasa, K.; J. Solid State Chem. 1998, 141, 229. 23. Sherman, D. M.; Wait, T. D.; Am. Mineral. 1985, 70, 1262. 15. Marangoni, R.; Bubniak, G. A.; Cantão, M. P.; Abbate, M.;
Schreiner, W. H.; Wypych, F.; J. Colloid Interface Sci. 2001,
240, 245. 24. Chai, H.; Lin, Y. J.; Evans, D. G.; Li, D. Q.; Ind. Eng. Chem. Res. 2008, 47, 2855. 25. Cui, G. J.; Xu, X. Y; Yan, J. L.; Evans, D. G.; Dian, Q. L.; Ind. Eng. Chem. Res. Conclusion 2010, 49, 448. 16. Arizaga, G. G. C.; Satyanarayana, K. G.; Wypych, F.; Solid
State Ionics 2007, 178, 1143. 26 Wypych, F.; Arizaga, G. G. C.; Gardolinski, J. E. F. D.; J. Colloid
Interface Sci. 2005, 283, 130. 17. Stählin, W.; Oswald, H. R.; Acta Crystallogr., Sect. B: Struct. Sci. 1970, 26, 860. 27. Nakamoto, K.; Infrared and Raman Spectra of Inorganic and
Coordination Compounds, 4th ed., John Wiley & Sons: New
York, 1986. 18. Newmann, S. P. Jones, W.; J. Solid State Chem. 1999, 148, 26. 19. Data Collection of the Joint Committee on Powder Diffraction
Standard, PCPDFWIN, Version 2.2, Copyright, 2001. 19. Data Collection of the Joint Committee on Powder Diffraction
St
d d PCPDFWIN V
i
2 2 C
i ht 2001 Standard, PCPDFWIN, Version 2.2, Copyright, 2001. Submitted: December 7, 2010
Published online: April 14, 2011 Submitted: December 7, 2010
Published online: April 14, 2011 J. Braz. Chem. Soc., Vol. 22, No. 6, S1-S7, 2011. Printed in Brazil - ©2011 Sociedade Brasileira de Química
0103 - 5053 $6.00+0.00 Supplementary Information *e-mail: delgado@unam.mx Arturo Cano,a María Teresa Ramírez-Apanb and Guillermo Delgado*,b aFacultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México,
Av. Guelatao no. 66 (Eje 7 Oriente), Col Ejército de Oriente, Iztapalapa 09230, Mexico, D.F. bInstituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, aFacultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México,
Av. Guelatao no. 66 (Eje 7 Oriente), Col Ejército de Oriente, Iztapalapa 09230, Mexico, D.F. bInstituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria,
Circuito Exterior, Coyoacán 04510, Mexico, D.F. Figure S1. 1H NMR (500 MHz, CDCl3) of 3α,6β-dihydroxysclareolide (16). Figure S1. 1H NMR (500 MHz, CDCl3) of 3α,6β-dihydroxysclareolide (16). *e-mail: delgado@unam.mx S2 Biotransformation of Sclareolide by Filamentous Fungi: Cytotoxic Evaluations of the Derivatives J. Braz. Chem. Soc. Biotransformation of Sclareolide by Filamentous Fungi: Cytotoxic Evaluations of the Derivatives
J. Braz. Chem. S2
Figure S2. 13C NMR (125 MHz, CDCl3) of 3α,6β-dihydroxysclareolide (16). Figure S3. HSQC (500 MHz, CDCl3) of 3α,6β-dihydroxysclareolide (16). Figure S2. 13C NMR (125 MHz, CDCl3) of 3α,6β-dihydroxysclareolide (16). Figure S2. 13C NMR (125 MHz, CDCl3) of 3α,6β-dihydroxysclareolide (16). Figure S3. HSQC (500 MHz, CDCl3) of 3α,6β-dihydroxysclareolide (16). Figure S3. HSQC (500 MHz, CDCl3) of 3α,6β-dihydroxysclareolide (16). Figure S3. HSQC (500 MHz, CDCl3) of 3α,6β-dihydroxysclareolide (16). S3 Vol. 22, No. 6, 2011 Cano et al. ,
,
Figure S4. 1H NMR (500 MHz, CDCl3) of 1-ketosclareolide (17). Figure S5. 13C NMR (125MHz, CDCl3) of 1-ketosclareolide (17). Figure S4. 1H NMR (500 MHz, CDCl3) of 1-ketosclareolide (17). Figure S4. 1H NMR (500 MHz, CDCl3) of 1-ketosclareolide (17). Figure S4. 1H NMR (500 MHz, CDCl3) of 1-ketosclareolide (17). Figure S5. 13C NMR (125MHz, CDCl3) of 1-ketosclareolide (17). Figure S5. 13C NMR (125MHz, CDCl3) of 1-ketosclareolide (17). Figure S5. 13C NMR (125MHz, CDCl3) of 1-ketosclareolide (17). Figure S5. 13C NMR (125MHz, CDCl3) of 1-ketosclareolide (17). Biotransformation of Sclareolide by Filamentous Fungi: Cytotoxic Evaluations of the Derivatives J. Braz. Chem. Soc. S4 Biotransformation of Sclareolide by Filamentous Fungi: Cytotoxic Evaluations of the Derivatives
J. Braz. Chem
S4
Figure S6. HMBC (500 MHz, CDCl3) of 1-ketosclareolide (17). Figure S7. 1H NMR (500MHz, CDCl3) of 3-keto-15-hydroxysclareolide (18). Figure S6. HMBC (500 MHz, CDCl3) of 1-ketosclareolide (17). Fi
S6 HMBC (500 MH
CDCl ) f 1 k
l
lid (17) Figure S6. HMBC (500 MHz, CDCl3) of 1-ketosclareolide (17). Figure S6. HMBC (500 MHz, CDCl3) of 1-ketosclareolide (17). Figure S7. 1H NMR (500MHz, CDCl3) of 3-keto-15-hydroxysclareolide (18). Figure S7. 1H NMR (500MHz, CDCl3) of 3-keto-15-hydroxysclareolide (18). Figure S7. J. Braz. Chem. Soc. Arturo Cano,a María Teresa Ramírez-Apanb and Guillermo Delgado*,b 1H NMR (500MHz, CDCl3) of 3-keto-15-hydroxysclareolide (18). Cano et al. S5
Vol. 22, No. 6, 2011
Figure S8. 13C NMR (125 MHz, CDCl3) of 3-keto-15-hydroxysclareolide (18). Figure S9. 1H NMR (500 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). S5 Vol. 22, No. 6, 2011 Cano et al. Figure S8. 13C NMR (125 MHz, CDCl3) of 3-keto-15-hydroxysclareolide (18). Figure S8. 13C NMR (125 MHz, CDCl3) of 3-keto-15-hydroxysclareolide (18). Figure S8. 13C NMR (125 MHz, CDCl3) of 3-keto-15-hydroxysclareolide (18). Figure S9. 1H NMR (500 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Figure S9. 1H NMR (500 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Biotransformation of Sclareolide by Filamentous Fungi: Cytotoxic Evaluations of the Derivatives J. Braz. Chem. Soc. S6 Biotransformation of Sclareolide by Filamentous Fungi: Cytotoxic Evaluations of the Derivatives
J. Braz. Chem
S6
Figure S10. 13C NMR (125 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Figure S11. COSY Spectrum (500 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Figure S10. 13C NMR (125 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Figure S10. 13C NMR (125 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Figure S10. 13C NMR (125 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Figure S11. COSY Spectrum (500 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Figure S11. COSY Spectrum (500 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Figure S11. COSY Spectrum (500 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Figure S11. COSY Spectrum (500 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). S7 Vol. 22, No. 6, 2011 Cano et al. Figure S12. HSQC (500 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19). Figure S12 HSQC (500 MHz CDCl ) of 3β 15 dihydroxysclareolide (19) Figure S12. HSQC (500 MHz, CDCl3) of 3β,15-dihydroxysclareolide (19).
|
https://openalex.org/W2898723770
|
https://discovery.ucl.ac.uk/id/eprint/10061487/1/LoreaBlazquez_1-s2.0-S1097276518308323-main.pdf
|
English
| null |
Exon Junction Complex Shapes the Transcriptome by Repressing Recursive Splicing
|
Molecular cell
| 2,018
|
cc-by
| 24,504
|
Exon Junction Complex Shapes the Transcriptome
by Repressing Recursive Splicing Authors
Lorea Blazquez, Warren Emmett,
Rupert Faraway, ..., Robert K. Bradley,
Manuel Irimia, Jernej Ule Authors
Lorea Blazquez, Warren Emmett,
Rupert Faraway, ..., Robert K. Bradley,
Manuel Irimia, Jernej Ule Correspondence
lorea.blazquez@crick.ac.uk (L.B.),
jernej.ule@crick.ac.uk (J.U.) Correspondence
lorea.blazquez@crick.ac.uk (L.B.),
jernej.ule@crick.ac.uk (J.U.) Blazquez et al., 2018, Molecular Cell 72, 496–509 q
November 1, 2018 ª 2018 The Author(s). Published by Elsevier Inc. Article Article Blazquez et al., 2018, Molecular Cell 72, 496–509
November 1, 2018 ª 2018 The Author(s). Published by Elsevier Inc.
https://doi.org/10.1016/j.molcel.2018.09.033 Exon Junction Complex Shapes the Transcriptome
by Repressing Recursive Splicing SUMMARY beginning. When the RS-exon is spliced to its preceding exon,
it reconstitutes a new 5ss (RS-5ss) at the exon-exon junction
of the part-spliced transcript (Figure 1A). In the second step of
RS, use of the RS-5ss leads to skipping the RS-exon along
with the downstream intron. Transcriptomic studies of RS-exons
in vertebrates and Drosophila have so far focused on cryptic
exons, which are removed without a trace due to the highly effi-
cient use of their RS-5ss (Joseph et al., 2018; Sibley et al., 2015). Nevertheless, we have identified very rare isoforms in a few
genes where the RS-exons are included and showed that the
inclusion of the RS-exon is determined by competition between
the RS-5ss and the downstream 5ss of the RS-exon (Figure 1A)
(Sibley et al., 2015). However, the factors that could bind to
the part-spliced transcript to regulate inclusion of RS-exons
remained unknown. Recursive splicing (RS) starts by defining an ‘‘RS-
exon,’’ which is then spliced to the preceding exon,
thus creating a recursive 50 splice site (RS-5ss). Pre-
vious studies focused on cryptic RS-exons, and now
we find that the exon junction complex (EJC) re-
presses RS of hundreds of annotated, mainly consti-
tutive RS-exons. The core EJC factors, and the pe-
ripheral factors PNN and RNPS1, maintain RS-exon
inclusion by repressing spliceosomal assembly on
RS-5ss. The EJC also blocks 5ss located near
exon-exon junctions, thus repressing inclusion of
cryptic microexons. The prevalence of annotated
RS-exons is high in deuterostomes, while the cryptic
RS-exons are more prevalent in Drosophila, where
EJC appears less capable of repressing RS. Notably,
incomplete repression of RS also contributes to
physiological alternative splicing of several human
RS-exons. Finally, haploinsufficiency of the EJC
factor Magoh in mice is associated with skipping of
RS-exons in the brain, with relevance to the micro-
cephaly phenotype and human diseases. The exon junction complex (EJC) is deposited on the spliced
transcript 20–24 nt upstream of each exon-exon junction. The EJC core is composed of eIF4A3 RNA helicase and MAGOH
and RBM8A that are deposited as a heterodimer that stabilizes
the binding of eIF4A3 by inhibiting its ATPase activity (Le Hir
et al., 2016). The EJC has multiple roles in post-splicing
events, such as mRNA transport, translation, and surveillance
by nonsense-mediated decay (NMD) (Le Hir et al., 2016). Exon Junction Complex Shapes
the Transcriptome by Repressing Recursive Splicing Lorea Blazquez,1,2,* Warren Emmett,1,2,3,9 Rupert Faraway,1,2,9 Jose Mario Bello Pineda,5,6,7,8 Simon Bajew,4
Andre Gohr,4 Nejc Haberman,1,2 Christopher R. Sibley,1,10 Robert K. Bradley,5,6,7 Manuel Irimia,4 and Jernej Ule1,2,11,*
1Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
2The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
3University College London Genetics Institute, Gower Street, London WC1E 6BT, UK
4Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr Aiguader 88, 08003 Barcelona, Spain
5Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
6Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
7Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
8Medical Scientist Training Program, University of Washington, Seattle, WA 98195, USA
9These authors contributed equally y
10Present address: Division of Brain Sciences, Department of Medicine, Imperial College London, Burlington Danes, DuCane Road,
London W12 0NN, UK
11Lead Contact *Correspondence: lorea.blazquez@crick.ac.uk (L.B.), jernej.ule@crick.ac.uk (J.U.)
https://doi.org/10.1016/j.molcel.2018.09.033 *Correspondence: lorea.blazquez@crick.ac.uk (L.B.), jernej.ule@crick.ac.uk (J.U.)
https://doi.org/10.1016/j.molcel.2018.09.033 *Correspondence: lorea.blazquez@crick.ac.uk (L.B.), jernej.ule@crick.ac.uk (J.U.)
https://doi.org/10.1016/j.molcel.2018.09.033 SUMMARY It
also promotes inclusion of specific exons in Drosophila (Ash-
ton-Beaucage et al., 2010; Roignant and Treisman, 2010) and
humans (Michelle et al., 2012; Wang et al., 2014), and the under-
lying mechanism was proposed to involve enhanced spliceo-
some recruitment to nearby splice sites or a change in the speed
of RNA polymerase II (PolII) elongation (Le Hir et al., 2016). eIF4A3 is deposited to the 50 exon during the splicing reaction
via interactions with the spliceosomal protein CWC22 before
the exon-exon junction is fully formed (Le Hir et al., 2016). Due
to its early recruitment, the EJC thus has the capacity to affect
the second step of any two-step splicing process. In Brief Blazquez et al. demonstrate that
hundreds of annotated exons can be
skipped from partly spliced transcripts
through a mechanism called recursive
splicing. Deposition of the exon junction
complex represses this mechanism,
which is particularly relevant in
deuterostomes and the brain, where it
can contribute to a microcephaly
phenotype and human disease. Highlights d Hundreds of RS-exons in human mRNAs reconstitute cryptic
5ss at exon-exon junctions d Hundreds of RS-exons in human mRNAs reconstitute cryptic
5ss at exon-exon junctions d EJC represses recursive splicing of RS-exons to preserve
transcriptome integrity d RS contributes to physiological alternative splicing d EJC-mediated repression is particularly important in
deuterostomes and in the brain Molecular Cell
Article Molecular Cell
Article 496
Molecular Cell 72, 496–509, November 1, 2018 ª 2018 The Author(s). Published by Elsevier Inc.
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). INTRODUCTION Alternative splicing (AS) is regulated by many proteins that bind
to the nascent RNA to modulate the initial step of exon definition
(Jangi and Sharp, 2014). However, less is known about the role of
proteins binding to spliced RNA, which could regulate a two-step
splicing process, such as recursive splicing (RS) (Hatton et al.,
1998; Sibley et al., 2015). RS starts by definition of an ‘‘RS-
exon,’’ which contains a partial 50 splice-site (5ss) motif at its We examined the role of the EJC in the regulation of RS. We find that the EJC blocks recognition of RS-5ss to promote RS-exon
3ss/5ss
RS-site
RS-5ss
RS-exon definition
5ss
5ss
‘Part-spliced’ transcript
Recursive splicing:
Cryptic RS-exon
RS-exon inclusion:
Annotated RS-exon
RS-exon
RS-exon
RS-5ss
5ss
RS-exon
aCADM2
aCADM2
400
500
300
Unspliced (Unsp)
Unsp
Part-spliced (Part)
Part
400
300
500
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
dPSI (%)
10
0
-10
-20
dPSI (%)
10
20
0
-10
-20
−11−8−5−2 1 4 7 10
−11−8−5−2 1 4 7 10
RS-5ss
RS-5ss
RS-5ss
RS-5ss
RS-5ss
RS-5ss
RS-5ss
RS-5ss
−11−8−5−2 1 4 7 10
−11−8−5−2 1 4 7 10
UPF1
RBM8A
CASC3
CASC3
eIF4A3
UPF1
RBM8A
eIF4A3
−9
−3
3
9
−9
−3
3
9
−9
−3
3
9
−9
−3
3
9
400
300
200
KPNA1
USF2
300
200
400
250
300
150
200
NLE1
KD
eIF4A3
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
200
300
100
MRPL3
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
KD
Ctrl
UPF1
RBM8A
MAGOH
EJC
9 100
RS-exon
skipping (%)
0 21 10 15 0
RS-exon
skipping (%)
0 44 32 32 0
RS-exon
skipping (%)
0 41 39 42 0
RS-exon
skipping (%)
0 21 25 19 0
RS-exon
skipping (%)
50 76 70 68 52
RS-exon
skipping (%)
Non RS-exon
Putative RS-exon
3.6% (n=6837)
Alternative:
6% (n=11075)
Alternative:
6.2 % (n=421)
96.4%
(n=185496)
EJC
RS-5ss
Wilcox test (Signed log P value)
40
20
60
0
0
−10
−20
−30
-40
UPF1
RBM8A
eIF4A3
CASC3
Constitutive
93.8%, n=6416
Constitutive
94%, n=174421
A
C
E
F
D
G
H
B
ure 1. INTRODUCTION The
RS-exon will be skipped if the RS-5ss is used for the second step of splicing and included if the canonical 5ss is used. (B) Pie charts show the prevalence of putative RS-exons in human mRNAs according to ENSEMBL GRCh37 annotation. (C) RT-PCR analysis of unspliced and part-spliced reporters derived from the alternative CADM2 (aCADM2) isoform after transient transfection into HeLa cells. (D) aCADM2 unspliced reporter was stably integrated into the genome of HeLa cells, and the splicing pattern of the RS-exon was analyzed by RT-PCR after
eIF4A3, RBM8A, MAGOH, and UPF1 KD. (E) Boxplots show the difference in percentage spliced in (dPSI) of highly included exons (PSI > 90%) after KD of eIF4A3, RBM8A, CASC3, or UPF1. Exons are
binned by their RS-5ss score, and dPSI for each bin is calculated by subtracting the PSI in the control experiment to each KD. The RS-5ss values on the x axis
indicate the midpoint of each group. Negative dPSI values indicate increased exon skipping upon KD. (F) Same as (E), but for alternative exons with a PSI < 90%. (G) The statistical significance of RS exon skipping is performed by dividing constitutive RS exons (PSI >0 98) into two groups based on a RS 5ss score g
p
(A) An RS-exon starts with a partial 5ss motif, and after the first step of splicing to the preceding exon, it generates RS-5ss within the part-spliced transcript. The
RS-exon will be skipped if the RS-5ss is used for the second step of splicing and included if the canonical 5ss is used. g
p
(A) An RS-exon starts with a partial 5ss motif, and after the first step of splicing to the preceding exon, it generates RS-5ss within the part-spliced transcript. The
RS-exon will be skipped if the RS-5ss is used for the second step of splicing and included if the canonical 5ss is used. (B) Pie charts show the prevalence of putative RS-exons in human mRNAs according to ENSEMBL GRCh37 annotation. (C) RT-PCR analysis of unspliced and part-spliced reporters derived from the alternative CADM2 (aCADM2) isoform after transient transfection into HeLa cells. (D) aCADM2 unspliced reporter was stably integrated into the genome of HeLa cells, and the splicing pattern of the RS-exon was analyzed by RT-PCR after
eIF4A3, RBM8A, MAGOH, and UPF1 KD. INTRODUCTION Core EJC Components Promote Inclusion of Putative ‘‘RS-Exons’’
n RS-exon starts with a partial 5ss motif, and after the first step of splicing to the preceding exon, it generates RS-5ss within the part-spliced transcript
exon will be skipped if the RS-5ss is used for the second step of splicing and included if the canonical 5ss is used. Pie charts show the prevalence of putative RS-exons in human mRNAs according to ENSEMBL GRCh37 annotation Non RS-exon
Putative RS-exon
3.6% (n=6837)
Alternative:
6% (n=11075)
Alternative:
6.2 % (n=421)
96.4%
(n=185496)
Constitutive
93.8%, n=6416
Constitutive
94%, n=174421
B RS-exon
3ss/5ss
RS-site
RS-5ss
RS-exon definition
5ss
5ss
‘Part-spliced’ transcript
Recursive splicing:
Cryptic RS-exon
RS-exon inclusion:
Annotated RS-exon
RS-exon
RS-exon
RS-5ss
5ss
RS-exon
A A B aCADM2
400
300
500
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
EJC
0 21 10 15 0
RS-exon
skipping (%)
EJC
D
G aCADM2
400
500
300
Unspliced (Unsp)
Unsp
Part-spliced (Part)
Part
9 100
RS-exon
skipping (%)
C
D RS-5ss
Wilcox test (Signed log P value)
40
20
60
0
0
−10
−20
−30
-40
UPF1
RBM8A
eIF4A3
CASC3
G C G D 400
300
200
KPNA1
250
300
150
200
NLE1
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
A3
OH
8A
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
0 44 32 32 0
RS-exon
skipping (%)
0 41 39 42 0
RS-exon
skipping (%)
H H E dPSI (%)
10
0
-10
-20
−11−8−5−2 1 4 7 10
−11−8−5−2 1 4 7 10
RS-5ss
RS-5ss
RS-5ss
RS-5ss
−11−8−5−2 1 4 7 10
−11−8−5−2 1 4 7 10
UPF1
RBM8A
CASC3
eIF4A3
F USF2
300
200
400
eIF4A3
200
300
100
MRPL3
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
KD
Ctrl
UPF1
RBM8A
MAGOH
pp g (
)
0 21 25 19 0
RS-exon
skipping (%)
50 76 70 68 52
RS-exon
skipping (%) F dPSI (%)
10
20
0
-10
-20
RS-5ss
RS-5ss
RS-5ss
RS-5ss
CASC3
UPF1
RBM8A
eIF4A3
−9
−3
3
9
−9
−3
3
9
−9
−3
3
9
−9
−3
3
9
F Figure 1. Core EJC Components Promote Inclusion of Putative ‘‘RS-Exons’’ Components Promote Inclusion of Putative ‘‘RS-Exons Figure 1. Core EJC Components Promote Inclusion of Putative RS Exons
(A) An RS-exon starts with a partial 5ss motif, and after the first step of splicing to the preceding exon, it generates RS-5ss within the part-spliced transcript. INTRODUCTION Thus, the first splicing step that
removes the preceding intron is crucial for RS-exon inclusion
in aCADM2, indicating that it might deposit factors such as
EJC onto the part-spliced transcript that repress the RS-5ss. To test if EJC indeed contributes to aCADM2 RS-exon inclu-
sion, we stably integrated the aCADM2 unspliced reporter into
HeLa cells and monitored the effect of eIF4A3, RBM8A, and
MAGOH KD. KD of either MAGOH or RBM8A led to depletion
of both factors, probably because they act as a heterodimer (Fig-
ure S1E). Notably, KD of any of the core EJC factors increased
the skipping of the aCADM2 RS exon (Figures 1D and S1F). As
control, we knocked down UPF1, which is required for NMD,
but did not affect RS-exon inclusion (Figures 1D and S1F). Thus, the changes in the isoform ratio upon EJC KD are not a
side effect of disturbing the NMD pathway. Given the prevalence of putative RS-exons in the human tran-
scriptome (Figure 1B), we reanalyzed previously published RNA
sequencing (RNA-seq) data from HeLa cells upon KD of EJC
factors to assess the broader effects on RS-exons. Specifically,
we plotted the difference in percentage spliced in (dPSI) in KD
compared to control for highly included (PSI > 90%) or alterna-
tive exons (PSI < 90%) according to the strength of their RS-
5ss (Figures 1E and 1F). dPSI values were grouped into equal
sized bins based on their RS-5ss scores, thereby avoiding any
initial assumptions in regard to the MaxEntScan score of a valid
5ss. A negative dPSI value indicated more skipping, whereas a
positive value denoted more inclusion upon KD. Remarkably,
most exons with increased skipping upon KD of EJC factors
(negative dPSI values) were those with highest RS-5ss scores. Independent analysis with the H-bond algorithm, an alternative
metric of 5ss strength (Freund et al., 2003), gave similar results
(data not shown). To assess if the trend toward exon skipping
with the increased RS-5ss score is statistically significant, we
divided all constitutive exons (PSI > 98) into two groups based
on their RS-5ss score and tested for a skew in dPSI values be-
tween the two groups by calculating a signed p value with the
Wilcoxon rank-sum test. By performing this analysis with
multiple thresholds, we confirmed that the trend toward exon
skipping as the RS-5ss score increases is highly significant (Fig-
ure 1G). RESULTS Core EJC Components Promote Inclusion of Putative
RS-Exons, which Are Abundant in the Transcriptome
We consider any exon that reconstitutes a 5ss (RS-5ss) at the
preceding exon-exon junction in the part-spliced transcript as
a putative RS-exon (Figure 1A). To assess the prevalence of
such putative RS-exons in human transcripts, we examined
the sequence at exon-exon junctions that precede all annotated
human exons using MaxEntScan software (Yeo and Burge,
2004). First, we defined a MaxEntScan threshold for putative
RS-exons by analyzing the distribution of canonical 5ss scores
at exon-intron junctions (Figure S1A). Next, we calculated the
MaxEntScan score at every exon-exon junction (RS-5ss) and
defined putative RS-exons as those with a RS-5ss that ex-
ceeded a given threshold. Using thresholds that detect 75% to
95% of canonical 50ss, the proportion of exons in the transcrip-
tome that would be classified as putative RS-exons varied be-
tween 1.7% and 4.9%, respectively (Figure S1B). For consis-
tency, all further analyses in this manuscript used a threshold
that detects 90% of human canonical 5ss, which has an associ-
ated MaxEntScan score of 5.52. According to this threshold,
3.6% of human exons are putative RS-exons (n = 6,837; Fig-
ure 1B), and 21.7% of genes (n = 4,900) and 16.2% of transcripts
(n = 5,295) contain at least one putative RS-exon (Figure S1C). The vast majority of putative RS-exons (93.8%, n = 6,416) are
constitutive according to ENSEMBL (Figure 1B), which raises the
question of why the RS-5ss of these exons are not used. To un-
derstand this question, we used a splicing reporter from the rare
isoform of CADM2 gene (aCADM2), which retains the RS-exon
(Sibley et al., 2015). We designed two versions of the reporter:
the unspliced version contains both introns flanking the RS-
exon, whereas the part-spliced version lacks the first intron. Strikingly, while the RS-exon is almost completely included in INTRODUCTION Moreover, EJC deposition also impedes the recognition of 5ss
located downstream of exon-exon junctions, thereby repressing
inclusion of short exons also known as microexons. The function
of the EJC is required for efficient inclusion of annotated RS-
exons in the mouse brain, as Magoh haploinsufficient brain
shows RS-exon skipping in genes that could contribute to the
microcephaly phenotype. Notably, analysis of PRPF8 iCLIP
and intron lariats shows that incomplete EJC-mediated repres-
sion of RS also represents a mechanism for physiological AS
of
several
human
RS-exons. Evolutionary
comparison
of
sequence features at exon-exon junctions shows that the num-
ber of annotated RS-exons increased in the deuterostome clade,
which contrasts the large number of cryptic RS-exons in
Drosophila. Taken together, we show that the EJC is required
to repress RS-5ss in mammalian mRNAs, which is required for
high inclusion of hundreds of annotated RS-exons, thus potently
shaping and regulating the mammalian transcriptome. inclusion of ‘‘annotated RS-exons.’’ Knockdown (KD) of core
EJC factors, and the peripheral factors RNPS1 and PNN, leads
to widespread skipping of annotated RS-exons via RS. We
show that depletion of eIF4A3 increases the assembly of spliceo-
some on RS-5ss, as demonstrated by crosslinking and immuno-
precipitation (iCLIP) with the core spliceosomal protein PRPF8. Moreover, EJC deposition also impedes the recognition of 5ss
located downstream of exon-exon junctions, thereby repressing
inclusion of short exons also known as microexons. The function
of the EJC is required for efficient inclusion of annotated RS-
exons in the mouse brain, as Magoh haploinsufficient brain
shows RS-exon skipping in genes that could contribute to the
microcephaly phenotype. Notably, analysis of PRPF8 iCLIP
and intron lariats shows that incomplete EJC-mediated repres-
sion of RS also represents a mechanism for physiological AS
of
several
human
RS-exons. Evolutionary
comparison
of
sequence features at exon-exon junctions shows that the num-
ber of annotated RS-exons increased in the deuterostome clade,
which contrasts the large number of cryptic RS-exons in
Drosophila. Taken together, we show that the EJC is required
to repress RS-5ss in mammalian mRNAs, which is required for
high inclusion of hundreds of annotated RS-exons, thus potently
shaping and regulating the mammalian transcriptome. the unspliced reporter, it is fully skipped in the part-spliced
reporter (Figures 1C and S1D). INTRODUCTION RT-PCR validated several annotated RS-exons as sen-
sitive to eIF4A3, RBM8A, and MAGOH KD, but not UPF1 (Figures
1H, S1G, and S1H). This confirms that all of the core EJC com-
ponents are crucial to inhibit the skipping of hundreds of putative
RS-exons. INTRODUCTION (E) Boxplots show the difference in percentage spliced in (dPSI) of highly included exons (PSI > 90%) after KD of eIF4A3, RBM8A, CASC3, or UPF1. Exons are
binned by their RS-5ss score, and dPSI for each bin is calculated by subtracting the PSI in the control experiment to each KD. The RS-5ss values on the x axis
indicate the midpoint of each group. Negative dPSI values indicate increased exon skipping upon KD. (F) Same as (E), but for alternative exons with a PSI < 90%. (G) The statistical significance of RS-exon skipping is performed by dividing constitutive RS-exons (PSI >0.98) into two groups based on a RS-5ss score
threshold, analyzing the differences in dPSI values between the two groups, and calculating a signed p-value by testing for a skew in dPSI values between the two
groups using the Wilcoxon rank-sum test. The analysis is done at multiple thresholds, from 40 to 8. (H) RT-PCR analysis of RS-exon splicing pattern after KD of EJC core factors or UPF1. Results shown in (C), (D), and (H) derive from a minimum of 3 independent experiments performed in HeLa cells. p
p
g
valence of putative RS-exons in human mRNAs according to ENSEMBL GRCh37 annotation. (D) aCADM2 unspliced reporter was stably integrated into the genome of HeLa cells, and the splicing pattern of the RS exon was analyzed by RT PCR after
eIF4A3, RBM8A, MAGOH, and UPF1 KD. (E) Boxplots show the difference in percentage spliced in (dPSI) of highly included exons (PSI > 90%) after KD of eIF4A3, RBM8A, CASC3, or UPF1. Exons are
binned by their RS-5ss score, and dPSI for each bin is calculated by subtracting the PSI in the control experiment to each KD. The RS-5ss values on the x axis
indicate the midpoint of each group. Negative dPSI values indicate increased exon skipping upon KD. Results shown in (C), (D), and (H) derive from a minimum of 3 independent experiments performed in HeLa cells. Molecular Cell 72, 496–509, November 1, 2018
497 Molecular Cell 72, 496–509, November 1, 2018
497 inclusion of ‘‘annotated RS-exons.’’ Knockdown (KD) of core
EJC factors, and the peripheral factors RNPS1 and PNN, leads
to widespread skipping of annotated RS-exons via RS. We
show that depletion of eIF4A3 increases the assembly of spliceo-
some on RS-5ss, as demonstrated by crosslinking and immuno-
precipitation (iCLIP) with the core spliceosomal protein PRPF8. 498
Molecular Cell 72, 496–509, November 1, 2018 PNN and RNPS1 Contribute to the Inclusion of
Annotated RS-Exons PNN and RNPS1 Contribute to the Inclusion of ‘‘Annotated RS-Exons’’ g
(A) The statistical significance of RS-exon skipping upon KD of 28 RBPs is performed by anal g
(A) The statistical significance of RS-exon skipping upon KD of 28 RBPs is performed by analysis of public RNA-seq data as explained in Figure 1G. Peripheral
EJC factors are marked in purple, and experiments that had no effect are marked in gray. (B) The statistical significance of RS-exon skipping upon KD of 191 RBPs calculated by analysis of ENCODE consortium RNA-seq, as in (A). Core EJC com-
ponents are marked in red, new factors that had an effect are marked in blue, and KD experiments that had no effect are marked in gray. (C) Distribution of dPSI after KD of different RBPs is shown for highly included exons in control (PSI > 90%), as explained in Figure 1E. (D) Same as (C), but for alternative exons with PSI < 90%. (E) RT-PCR validation of RS-exon skipping after KD of eIF4A3, RNPS1, or PNN (n = 3 independent experiments for KLHL20 and TMA16; n = 2 for EGLN1, KPNA1,
MRPL3, and SACM1L). EJC factors are marked in purple, and experiments that had no effect are marked in gray. (B) The statistical significance of RS-exon skipping upon KD of 191 RBPs calculated by analysis of ENCODE consortium R
ponents are marked in red, new factors that had an effect are marked in blue, and KD experiments that had no effect are ma
(C) Distribution of dPSI after KD of different RBPs is shown for highly included exons in control (PSI > 90%), as explained in
(D) Same as (C), but for alternative exons with PSI < 90%. (E) RT-PCR validation of RS-exon skipping after KD of eIF4A3, RNPS1, or PNN (n = 3 independent experiments for KLHL20 and
MRPL3, and SACM1L). ASCC1 KD (Figure 2B). Notably, KD of other factors that were re-
ported to associate with the EJC, such as SRSF1 and SRSF3
serine/arginine-rich (SR) proteins (Singh et al., 2012) or compo-
nents of the NMD machinery, did not show any effect, indicating
that they do not play an important role in the EJC assembly on
part-spliced transcripts. evident, even though the effect was milder and most apparent
for RNPS1 and MAGOH (Figure 2D). PNN and RNPS1 Contribute to the Inclusion of
Annotated RS-Exons For insights into additional factors that contribute to inclusion of
RS-exons, we analyzed all available RNA-seq data from studies
that included KD of at least one previously reported EJC-associ-
ated factor. Then we examined if there is a significant trend for
skipping of constitutive exons with high RS-5ss. KD of EJC
peripheral components RNPS1, PNN, and ACIN1 showed signif-
icant effects, although the effect of ACIN1 was very weak (Fig-
ure 2A). We also analyzed RNA-seq data from the ENCODE Con-
sortium that includes KD of 191 RNA binding proteins (RBPs) and
identified significant effects for eIF4A3, MAGOH, SUPV3L1, and 498
Molecular Cell 72, 496–509, November 1, 2018 RS-5ss
RS-5ss
Wilcox test (Signed log P value)
40
20
60
0
0
−10
−20
−30
-40
21 KD, including SRSF1, SRSF3, SMG6
ACIN1
PNN
RNPS1
Wilcox test (Signed log P value)
0
−10
-20
0
40
80
187 ENCODE
KD, including:
UPF2, SRSF1,
SRSF7
MAGOH
ASCC1
eIF4A3
SUPV3L1
PNN
RNPS1
−11−8−5−2 1 4 7 10 −11−8−5−2 1 4 7 10 −11−8−5−2 1 4 7 10 −11−8−5−2 1 4 7 10
MAGOH−K562
eIF4A3−K562
eIF4A3−K562
PNN
RNPS1
−9
−3
3
9
−9
−3
3
9
MAGOH−K562
−9
−3
3
9
−9
−3
3
9
KD
eIF4A3
Ctrl
PNN
RNPS1
KD
eIF4A3
Ctrl
PNN
RNPS1
400
300
200
100
EGLN1
400
300
200
100
400
300
200
100
300
200
100
TMA16
RS-5ss
RS-5ss
RS-5ss
RS-5ss
RS-5ss
RS-5ss
RS-5ss
RS-5ss
KD
KLHL20
0 20 31 13
RS-exon
skipping (%)
3 2 25 14
RS-exon
skipping (%)
10 19 42 21
RS-exon
skipping (%)
KD
eIF4A3
Ctrl
PNN
RNPS1
eIF4A3
Ctrl
PNN
RNPS1
eIF4A3
Ctrl
PNN
RNPS1
KD
eIF4A3
Ctrl
PNN
RNPS1
400
300
200
100
KPNA1
400
500
300
200
MRPL3
KD
SACM1L
0 15 0 0
RS-exon
skipping (%)
0 9 24 10
RS-exon
skipping (%)
0 9 5 3
RS-exon
skipping (%)
dPSI (%)
10
20
0
-10
-20
dPSI (%)
10
0
-10
-20
A
C
E
D
B
Figure 2. PNN and RNPS1 Contribute to the Inclusion of ‘‘Annotated RS-Exons’’
(A) The statistical significance of RS-exon skipping upon KD of 28 RBPs is performed by analysis of public RNA-seq data as explained in Figure 1G. Peripheral
EJC factors are marked in purple, and experiments that had no effect are marked in gray. PNN and RNPS1 Contribute to the Inclusion of
Annotated RS-Exons (B) The statistical significance of RS-exon skipping upon KD of 191 RBPs calculated by analysis of ENCODE consortium RNA-seq, as in (A). Core EJC com-
ponents are marked in red, new factors that had an effect are marked in blue, and KD experiments that had no effect are marked in gray. (C) Distribution of dPSI after KD of different RBPs is shown for highly included exons in control (PSI > 90%), as explained in Figure 1E. (D) Same as (C), but for alternative exons with PSI < 90%. (E) RT-PCR validation of RS-exon skipping after KD of eIF4A3, RNPS1, or PNN (n = 3 independent experiments for KLHL20 and TMA16; n = 2 for EGLN1, KPNA1,
MRPL3, and SACM1L). RS-5ss
Wilcox test (Signed log P value)
40
20
60
0
0
−10
−20
−30
-40
21 KD, including SRSF1, SRSF3, SMG6
ACIN1
PNN
RNPS1
A RS-5ss
Wilcox test (Signed log P value)
0
−10
-20
0
40
80
187 ENCODE
KD, including:
UPF2, SRSF1,
SRSF7
MAGOH
ASCC1
eIF4A3
SUPV3L1
B A B A KD
eIF4A3
Ctrl
PNN
RNPS1
400
300
200
100
EGLN1
0 20 31 13
RS-exon
skipping (%)
E E KD
eIF4A3
Ctrl
PNN
RNPS1
400
300
200
100
KPNA1
0 15 0 0
RS-exon
skipping (%) C PNN
RNPS1
−11−8−5−2 1 4 7 10 −11−8−5−2 1 4 7 10 −11−8−5−2 1 4 7 10 −11−8−5−2 1 4 7 10
MAGOH−K562
eIF4A3−K562
RS-5ss
RS-5ss
RS-5ss
RS-5ss
dPSI (%)
10
0
-10
-20
C KD
eIF4A3
Ctrl
PNN
RNPS1
400
300
200
100
TMA16
10 19 42 21
RS-exon
skipping (%) 400
300
200
100
300
200
100
KD
eIF4A3
Ctrl
PNN
RNPS1
eIF4A3
Ctrl
PNN
RNPS1
MRPL3
KD
SACM1L
0 9 24 10
RS-exon
skipping (%)
0 9 5 3
RS-exon
skipping (%) 300
200
100
KD
eIF4A3
Ctrl
PNN
RNPS1
MRPL3
0 9 5 3
RS-exon
skipping (%) D eIF4A3−K562
PNN
RNPS1
−9
−3
3
9
−9
−3
3
9
MAGOH−K562
−9
−3
3
9
−9
−3
3
9
RS-5ss
RS-5ss
RS-5ss
RS-5ss
dPSI (%)
10
20
0
-10
-20
D KD
KLHL20
3 2 25 14
RS-exon
skipping (%)
eIF4A3
Ctrl
PNN
RNPS1
400
500
300
200 400
300
200
100
eIF4A3
Ctrl
PNN
RNPS1
KD
SACM1L
0 9 24 10
RS-exon
skipping (%) Figure 2. PNN and RNPS1 Contribute to the Inclusion of
Annotated RS-Exons RT-PCR analysis after KD
of eIF4A3, RNPS1, or PNN in HeLa cells indicated that each an-
notated RS-exon has a unique sensitivity profile to the depletion
of different EJC factors. Some RS-exons (i.e., KPNA1) do not
require EJC peripheral factors for their inclusion, whereas others
are more sensitive to peripheral factors than to core factors (Fig-
ures 2E and S2C). Analysis of ENCODE data uncovered two un-
expected factors, SUVP3L1 and ASCC1 (Figure 2B). We noticed
that the short hairpin RNA (shRNA) sequence used for SUVP3L1
KD is highly complementary to eIF4A3 mRNA and results in a
strong downregulation of eIF4A3 (Figure S2F). When we used a To further visualize the splicing changes, we plotted the
KD-induced change in PSI (DPSI) for groups of exons with similar
RS-5ss scores (Figure 2C). Highly included annotated RS-exons
generally increased skipping by 4%–10% upon KD of core EJC
components and 3%–6% upon KD of RNPS1 and PNN. PNN and RNPS1 Contribute to the Inclusion of
Annotated RS-Exons Increased skipping of alternative annotated RS-exons was also Molecular Cell 72, 496–509, November 1, 2018
499 300
400
250
200
Ctrl
400
500
KD
KD
Ctrl
Ctrl KPNA1
Ctrl
KPNA1 ASO
300
400
250
200
300
400
250
200
400
500
300
250
Endogenous KPNA1
Mutant RS-5ss KPNA1
ASO
eIF4A3
eIF4A3
Unsp
Part
Part
Mut
KPNA1 splicing reporter
Ctrl siRNA
eIF4A3 siRNA
6 8.5 10.7
C
D
A
B
E
F
G
H
Unspliced (Unsp)
Part-spliced (Part)
GT
GT
Part Mutant (Part Mut)
GC
300
400
500
600
Wt No RS-exon
Mut RS-exon
KD
Ctrl
Ctrl
eIF4A3
eIF4A3
PSMA3-AS1 alternative RS-exon
aCADM2 canonical RS-exon
KPNA1 canonical RS-exon
6 8.5 10.7
RS-exon
skipping (%)
RS-5ss
score
RS-5ss
score
RS-5ss
score
0 0 34 0 16 41
RS-exon
skipping (%) 0 52
RS-exon
skipping (%) 0 0
RS-exon
skipping (%) 0 10
RS-exon
skipping (%) 1 48 0
RS-exon
skipping (%)
0 0
Ctrl siRNA
eIF4A3 siRNA
6 9.6 11
6 9.6 11
RS-exon
skipping (%)
0 100 100 64 100 100
RS-exon
skipping (%)
0 0 0 40
siRNA
Ctrl
eIF4A3
5.3 8.5
5.3 8.5
RS-exon
skipping (%)
8 76 13 72
EJC
EJC
GC
GC
EJC
EJC
GT
GT
Wild-type RPS2 non RS-exon
(Wt No RS-exon)
Mutant RPS2 RS-exon
(Mut RS-exon)
EJC
EJC
GT
GT
EJC
EJC
GC
GC
Endogenous KPNA1
Mutant RS-5ss KPNA1
GC
GC
EJC
GT
GT
ASO
ASO
ASO
ASO
EJC
Exon
Sequence at exon-
exon junction
RS-5ss
Score
KPNA1 RS-exon
CAG/GTAATT
8.5
KPNA1 Mut RS-5ss
CAG/GCAGCT
-1.2
KPNA1 6
CAG/GTGATG
6
KPNA1 10.7
CAG/GTAAGA
10.7
aCADM2 RS-exon
AGT/GTAAGC
5.3
aCADM2 Mut RS 5ss
AGT/GCAGCC
-12.9
aCADM2 8.5
AGT/GTAAGT
8.5
RPS2 Non RS-exon
AAG/GCATTT
-0.1
RPS2 Mut RS-exon
AAG/GTATTT
7.6
PSMA3-AS1 RS-exon
AAG/GTGAGC
9.6
PSMA3-AS1 6
AAG/GTGGGA
6
PSMA3-AS1 11
AAG/GTAAGT
11
0
1e−07
2e−07
3e−07
−50
−40
−30
−20
−10
0
Control
eIF4A3 siRNA
0
1e−08
2e−08
−50
−40
−30
−20
−10
0
Normalised read count
Normalised read count
Control
eIF4A3 siRNA
RS
Non-RS
RS
Non-RS
Reads spanning
exon-intron junction
Reads spanning
exon-exon junction
Distance to exon-intron junction (nt)
Distance to exon-exon junction (nt)
5ss
RS-5ss
300
300
300
400
400
400
500
500
500
Figure 3. PNN and RNPS1 Contribute to the Inclusion of
Annotated RS-Exons The
d t
th d
i
l
ll
i ht d
tt
l t
thi
(LOESS) Sh d d
i
t 95%
fid
i t
l Control
eIF4A3 siRNA
RS
Non-RS
Reads spanning
exon-intron junction
5ss A
0
1e−07
2e−07
3e−07
−50
−40
−30
−20
−10
0
Control
eIF4A3 siRNA
Normalised read count
RS
Non-RS
Reads spanning
exon-intron junction
Distance to exon-intron junction (nt)
5ss A
0
1e−07
2e−07
3e−07
−50
−40
−30
−20
−10
0
Normalised read count
Distance to exon-intron junction (nt) B
0
1e−08
2e−08
−50
−40
−30
−20
−10
0
Normalised read count
Control
eIF4A3 siRNA
RS
Non-RS
Reads spanning
exon-exon junction
Distance to exon-exon junction (nt)
RS-5ss B A D
Endogenous KPNA1
EJC
GT
GT
ASO
ASO Mutant RS-5ss KPNA1
GC
GC
ASO
ASO
EJC D Mutant RS-5ss KPNA1
EJC
EJC
GC
GC KPNA1 splicing reporter
E
Unspliced (Unsp)
Part-spliced (Part)
GT
GT
Part Mutant (Part Mut)
GC Endogenous KPNA1
C
EJC
EJC
GT
GT E C KPNA1 splicing reporter Mutant RS-5ss KPNA1 Mutant RS-5ss KPNA1 300
400
250
200
Unsp
Part
Part
Mut
RS-exon
skipping (%) 1 48 0 Ctrl KPNA1
300
400
250
200
ASO
RS-exon
skipping (%) 0 10 Ctrl
400
500
KD
eIF4A3
RS-exon
skipping (%) 0 0 Ctrl
KPNA1 ASO
400
500
300
250
RS-exon
skipping (%)
0 0 300
400
250
200
KD
Ctrl eIF4A3
RS-exon
skipping (%) 0 52
s PSMA3-AS1 alternative RS-exon
RS-5ss
score
Ctrl siRNA
eIF4A3 siRNA
6 9.6 11
6 9.6 11
RS-exon
skipping (%)
0 100 100 64 100 100
300
400
500 PSMA3-AS1 alternative RS-exon F
aCADM2 canonical RS-exon
RS-5ss
score
siRNA
Ctrl
eIF4A3
5.3 8.5
5.3 8.5
RS-exon
skipping (%)
8 76 13 72
300
400
500 Ctrl siRNA
eIF4A3 siRNA
6 8.5 10.7
KPNA1 canonical RS-exon
6 8.5 10.7
RS-exon
skipping (%)
RS-5ss
score
0 0 34 0 16 41
300
400
500 F KPNA1 canonical RS-exon G H G
Exon
Sequence at exon-
exon junction
RS-5ss
Score
KPNA1 RS-exon
CAG/GTAATT
8.5
KPNA1 Mut RS-5ss
CAG/GCAGCT
-1.2
KPNA1 6
CAG/GTGATG
6
KPNA1 10.7
CAG/GTAAGA
10.7
aCADM2 RS-exon
AGT/GTAAGC
5.3
aCADM2 Mut RS 5ss
AGT/GCAGCC
-12.9
aCADM2 8.5
AGT/GTAAGT
8.5
RPS2 Non RS-exon
AAG/GCATTT
-0.1
RPS2 Mut RS-exon
AAG/GTATTT
7.6
PSMA3-AS1 RS-exon
AAG/GTGAGC
9.6
PSMA3-AS1 6
AAG/GTGGGA
6
PSMA3-AS1 11
AAG/GTAAGT
11 300
400
500
600
Wt No RS-exon
Mut RS-exon
KD
Ctrl
Ctrl
eIF4A3
eIF4A3
RS-exon
skipping (%)
0 0 0 40 Wild-type RPS2 non RS-ex
(Wt No RS-exon)
EJC
EJC
GC
GC Wild-type RPS2 non RS-exon
(Wt No RS-exon)
Mutant RPS2 RS-exon
(Mut RS-exon)
EJC
EJC
GT
GT
EJC
EJC
GC
GC xon
Mutant RPS2 RS-exon
(Mut RS-exon)
EJC
EJC
GT
GT Figure 3. PNN and RNPS1 Contribute to the Inclusion of
Annotated RS-Exons Skipping of Annotated RS-Exons upon EJC KD Results from Recursive Splicing
(A) The count of PRPF8 iCLIP reads that identify crosslinks at each nucleotide upstream of exon-intron junctions is normalized by the total number of evaluated
junctions (RS = 4,631; non-RS = 130,410) and the total number of crosslinks in each experiment. HeLa cells treated with either control or eIF4A3 siRNAs were
used for iCLIP (n = 4 per group, 2 independent experiments). Reads upstream of RS-exons and non RS-exons are plotted in orange and gray, respectively. PNN and RNPS1 Contribute to the Inclusion of
Annotated RS-Exons Skipping of Annotated RS-Exons upon EJC KD Results from Recursive Splicing (A) The count of PRPF8 iCLIP reads that identify crosslinks at each nucleotide upstream of exon-intron junctions is normalized by the total number of evaluated
junctions (RS = 4,631; non-RS = 130,410) and the total number of crosslinks in each experiment. HeLa cells treated with either control or eIF4A3 siRNAs were
used for iCLIP (n = 4 per group, 2 independent experiments). Reads upstream of RS-exons and non RS-exons are plotted in orange and gray, respectively. The
data were smoothed using locally weighted scatterplot smoothing (LOESS). Shaded regions represent 95% confidence intervals. (B) Density plot as in (A), but assessing PRPF8 iCLIP upstream of exon-exon junctions. Crosslinks upstream of RS-exons or non RS-exons are plotted in blue or
gray, respectively. (D) Same analysis as in (C), after transfecting cells with an antisense oligonucleotide complementary to the EJC deposition site
(E) RT-PCR analysis of wild-type and mutant unspliced and part-spliced reporters derived from the KPNA1 gene after t
HeLa cells. (F) RT-PCR analysis of RS-exon splicing pattern after transient transfection of wild-type or mutant aCADM2, KPNA1, and PSMA
treated with control or eIF4A3 siRNAs. The original RS-5ss score is indicated in bold, and the scores after mutation are in regu (legend continued on next page) 500
Molecular Cell 72, 496–509, November 1, 2018 Finally, we asked if the order of intron removal might play a
role (Kim et al., 2017) by examining paired-end RNA-seq reads
that map to both ends of annotated RS-exons. If one crossed
to the preceding exon and the other crossed to the downstream
intron, then the read pair was considered as evidence for the up-
stream intron being spliced first (co-transcriptional splicing),
whereas the reciprocal scenario was considered as evidence
for the downstream intron being spliced first (Figure S3C). This
analysis indicates that EJC-sensitive RS-exons more often
follow a co-transcriptional splicing order when compared to
non-sensitive RS-exons. Moreover, EJC-sensitive RS-exons
tend to have a stronger 3ss and weaker 5ss, which could also
explain why the upstream intron tends to be spliced first (Fig-
ure S3C). It is crucial for efficient RS that the upstream intron is
spliced first in order to form the RS-5ss that can be used for
the second splicing event. We conclude that the annotated
RS-exons need to have an asymmetric splicing pattern to be
capable of RS upon EJC KD. g
from RS We selected several annotated RS-exons for further mecha-
nistic studies with minigene reporters. First, we confirmed that
RS-exons require the intact RS-5ss to be efficiently skipped
upon eIF4A3 KD, since stable cell lines expressing KPNA1 and
aCADM2 unspliced reporters with point mutations at the begin-
ning of their RS-exons remain constitutive (Figures 3C, S3D, and
S3E). Second, we blocked EJC binding to the exon preceding
KPNA1 RS-exon using an antisense oligonucleotide (KPNA1
ASO) complementary to the region where the EJC is deposited. KPNA1 ASO transfection increased skipping of KPNA1 RS-exon
from the endogenous gene, similar to the effect of eiF4A3 KD. In contrast, KPNA1 ASO did not promote skipping of KPNA1
RS-5ss mutant exon (Figures 3D and S3F). Finally, as in
aCADM2, KPNA1 reporters that correspond to the sequence
produced at the part-spliced stage showed RS-exon skipping,
which was dependent on the presence of the intact RS-5ss (Fig-
ures 3E, S3G, and S3H). To validate RS as the mechanism responsible for skipping of
annotated RS-exons, we performed PRPF8 iCLIP in eIF4A3 KD
and control conditions. PRPF8 is an integral component of the
U5 small nuclear ribonucleoprotein particle (snRNP) and binds
upstream of 5ss (Teigelkamp et al., 1995). Since iCLIP cDNAs
generally truncate at the crosslink sites of RBPs (Haberman
et al., 2017), we expected that the ungapped PRPF8 iCLIP reads
could be mapped across exon-intron junctions and gapped
reads across exon-exon junctions to validate spliceosome as-
sembly at canonical 5ss and RS-5ss, respectively. Indeed, the
ungapped reads identified a sharp PRPF8 crosslinking peak
12–14 nt upstream of 5ss (Figure 3A). The peak did not change
upon eIF4A3 KD, demonstrating that eIF4A3 has no general ef-
fect on canonical 5ss recognition (Figure 3A). Strikingly, gapped
reads also identified a PRPF8 crosslinking peak 12–14 nt
upstream of exon-exon junctions that precede RS-exons (Fig-
ure 3B). This peak was dramatically increased upon eIF4A3
KD, with no change at non-RS exons, confirming that eIF4A3
blocks spliceosome assembly on RS-5ss across the transcrip-
tome, thereby blocking RS. We have previously shown that efficient RS of cryptic RS-
exons requires strong RS-5ss that can outcompete the down-
stream 5ss of the RS-exon (Sibley et al., 2015). In agreement,
increasing the RS-5ss score in aCADM2 and KPNA1 RS-exons
induced their skipping even in the presence of the EJC (Figures
3F and S3I). PNN and RNPS1 Contribute to the Inclusion of
Annotated RS-Exons different small interfering RNA (siRNA) sequence for SUVP3L1
KD, we could not validate any of the splicing changes detected
in ENCODE RNA-seq data (Figure S2G), indicating that the
changes seen in ENCODE data were most likely caused by off-
target effect of SUVP3L1 shRNA. In the case of ASCC1 KD,
the trend toward RS-exon skipping was minor and could also
not be validated (Figures 2B and S2E). Taken together, our re-
sults show that the core and peripheral EJC factors are required
to repress skipping of both constitutive and alternative anno-
tated RS-exons, which supports previous biochemical findings
that RNPS1 and PNN associate at the earliest stages of EJC as-
sembly in the nucleus (Le Hir et al., 2016). Variable sensitivities of
RS-exons for KD of different factors also agree with previous
findings that the importance of each factor in EJC assembly
could vary between exon-exon junctions (Saulie` re et al., 2012;
Singh et al., 2012). Skipping of Annotated RS-Exons upon EJC KD Results
f
RS (G) Nucleotide sequences at the exon-exon junctions and their associated RS-5ss scores for the splicing reporters used in (C), (F), and (H). The nucleotides before
and after the slash sign correspond to the last 3 nt of the preceding exon and the first 6 nt of the exon under study. Mutations are indicated in red.
(H) Wild-type and mutant splicing reporters derived from RPS2 gene were transiently transfected into HeLa cells, and their splicing pattern was analyzed by
RT-PCR after control or eIF4A3 KD. Figure
4. Stable
EJC
Deposition
Is
Required to Block Recursive Splicing Ctrl
siRNA:
GFP
GFP
Wt
Wt
E188R
E188Q
401/402
E20R
GFP
MAGOH
rescue
protein:
300
250
200
150
KPNA1 RS-exon
eIF4A3
Ctrl
siRNA:
GFP
GFP
Wt
Wt
E188R
E188Q
401/402
E20R
GFP
MAGOH
rescue
protein:
aCADM2 RS-exon
eIF4A3
400
300
EJC Knockdown and Rescue
of annotated RS-exon inclusion
RS-exon
skipping (%) 0 12 0 17 0 19 22 0 26
RS-exon
skipping (%) 0 3 0 3 0 8 4 0 5
EJC
GT
GT
Flag
A B EJC Knockdown and Rescue
of annotated RS-exon inclusion (A) KD of EJC components was rescued with
siRNA-resistant FLAG-tagged counterparts. The
splicing pattern of endogenous KPNA1 or stably
integrated aCADM2 RS-exons was monitored by
RT-PCR. (B) Wild-type or mutant SL2 sequence was in-
serted into KPNA1 and mCADM2 splicing re-
porters at the expected EJC deposition site,
and the splicing pattern was monitored by RT-
PCR after co-transfection of SL2 reporters and
plasmids expressing the indicated MS2-tagged
proteins. A minimum of 3 independent replicates was per-
formed in HeLa (A) or 293 (B) cells. SL2 Wt
SL2 Mut
Tethered
protein:
Splicing
reporter:
MS2-GFP
GFP
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-GFP
GFP
400
600
500
88 33 48 62 84 85 74 88
mCADM2 RS-exon
RS-exon
skipping (%) SL2 Mut
MS2-GFP
F4A3
/402
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-GFP
GFP
62 84 85 74 88
(MS2-CP)
fused
to
either
wild-type
eIF4A3 or eIF4A3 401/402 mutant, which
does
not
assemble
the
EJC. Both
wild-type and eIF4A3 401/402 mutant
efficiently repressed KPNA1 RS-exon
skipping, whereas MS2-GFP could not
(Figures 4B and S4G). As a negative con-
trol we designed a KPNA1 SL2 Mut
splicing reporter, where SL2 mutation
prevents tethering of the MS2-CP, to confirm that MS2-eIF4A3
is incapable of repression without tethering (Figures 4B and
S4G). Notably, tethering MS2-eIF4A3 upstream of the exon-
exon junction of a cryptic RS-exon in the CADM2 gene
(mCADM2) that normally undergoes very efficient RS (Sibley
et al., 2015) also turned it into a highly included exon (Figures
4B and S4H). Thus, endogenous EJC assembly is crucial to
repress RS, while the tethered assembly-deficient eIF4A3 401/
402 mutant is efficient on its own. This observation demonstrates
that the role of endogenous EJC assembly is to stabilize eIF4A3
binding on the part-spliced transcript in order to repress RS. presence of EJC and whether it becomes skipped upon deple-
tion of the EJC. g
from RS In a reciprocal experiment, decreasing the RS-5ss
score in constitutive RS-exons made the constitutive KPNA1
RS-exon completely insensitive to EJC depletion, while the
PSMA3-AS1 RS-exon becomes less sensitive (Figures 3F and
S3I). Both RS-exons shared the same RS-5ss score (Figure 3G),
but their variable sensitivity could result from differences in their
RS-5ss sequences, the structure of RNA, or other RBPs that bind
nearby to modulate U1 snRNP recognition. Importantly, a GC-
to-GT mutation at the beginning of the RPS2 non RS-exon was
sufficient to turn it into a RS-exon sensitive to eIF4A3 KD (Figures
3H and S3J). In conclusion, it is clear the strength of RS-5ss de-
termines whether an RS-exon is constitutive or alternative in the PRPF8 crosslinking also confirmed that RNA-seq is generally
appropriate to classify RS-exons based on their sensitivity to
EJC perturbation, since increased PRPF8 crosslinking is most
apparent at EJC-sensitive RS-exons, which were defined by
RNA-seq (Figure S3A). This sensitivity cannot be explained by
the sequence of the RS-5ss, since both sensitive and insensitive
RS-exons have similar MaxEntScan scores (data not shown). Next, we asked if differences in EJC assembly might explain
the differential sensitivity. For this, we turned to the previously
published iCLIP data for EJC components (Hauer et al., 2016)
to compare crosslinking of EJC components at exon-exon junc-
tions. However, no differential EJC binding was observed be-
tween the sensitive and insensitive RS-exons (Figure S3B). (G) Nucleotide sequences at the exon-exon junctions and their associated RS-5ss scores for the splicing reporters used in (C), (F), and (H). The nucleotides before
and after the slash sign correspond to the last 3 nt of the preceding exon and the first 6 nt of the exon under study. Mutations are indicated in red. (H) Wild-type and mutant splicing reporters derived from RPS2 gene were transiently transfected into HeLa cells, and their splicing pattern was analyzed by
RT-PCR after control or eIF4A3 KD. Results shown in (C)–(F) and (H) derive from a minimum of 3 independent replicates. Figure
4. Stable
EJC
Deposition
Is
Required to Block Recursive Splicing Altogether, the PRPF8 iCLIP and minigene ex-
periments demonstrate that the increased skipping of annotated
RS-exons upon EJC KD is a result of RS. EJC Assembly Is Required to Stabilize eIF4A3 Binding to
Block RS We next asked if assembly of the complete EJC is crucial to inhibit
RS. We first established siRNA-resistant FLAG-tagged eIF4A3 or
MAGOH constructs, which efficiently rescued aCADM2 and
KPNA1 RS-exon inclusion when expressed at similar levels to
their endogenous counterparts upon EJC KD (Figure S4A). We
then used three mutants (eIF4A3 E188R, eIF4A3 401/402, and
MAGOH E20R) previously reported to be unable to assemble
the EJC (Gehring et al., 2009), which could not rescue the function
of the endogenous proteins (Figures 4A, S4B, and S4C). Interest-
ingly,expressionofthesemutantsalso inducedRS-exonskipping
under control conditions (Figures S4D and S4E), in agreement
with their previously described dominant-negative function
(Wang et al., 2014). On the contrary, the eIF4A3 E188Q mutant,
which inactivates the ATPase activity of eIF4A3 while remaining
capable of EJC assembly (Shibuya et al., 2006), rescued the func-
tion of the endogenous protein (Figure 4A, S4B, and S4C). Taken
together, this confirms that stable assembly of the endogenous
EJC is required to repress RS of annotated RS-exons. g
from RS –(F) and (H) derive from a minimum of 3 independent replicates Molecular Cell 72, 496–509, November 1, 2018
501 RS-5ss
Wild type
Stem Loop 2 (SL2)
MS2
Mutated
Stem Loop 2 (SL2 Mut)
400
600
300
SL2 Wt
SL2 Mut
Tethered
protein:
Splicing
reporter:
MS2-GFP
GFP
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-GFP
GFP
SL2 Wt
SL2 Mut
Tethered
protein:
Splicing
reporter:
MS2-GFP
GFP
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-GFP
GFP
400
600
500
RS-exon
skipping (%) 23 2 2 21 19 15 28 19
88 33 48 62 84 85 74 88
KPNA1 RS-exon
mCADM2 RS-exon
RS-exon
skipping (%)
eIF4A3 tethering to the exon
preceding the RS-exon
RS-5ss
MS2
MS2
MS2
B RS-5ss
Wild type
Stem Loop 2 (SL2)
MS2
Mutated
Stem Loop 2 (SL2 Mut)
Ctrl
siRNA:
GFP
GFP
Wt
Wt
E188R
E188Q
401/402
E20R
GFP
MAGOH
rescue
protein:
300
250
200
150
KPNA1 RS-exon
400
600
300
SL2 Wt
SL2 Mut
Tethered
protein:
Splicing
reporter:
eIF4A3
MS2-GFP
GFP
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-GFP
GFP
SL2 Wt
SL2 Mut
Tethered
protein:
Splicing
reporter:
MS2-GFP
GFP
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-eIF4A3
MS2- eIF4A3
401/402
MS2-GFP
GFP
400
600
500
RS-exon
skipping (%) 23 2 2 21 19 15 28 19
88 33 48 62 84 85 74 88
Ctrl
siRNA:
GFP
GFP
Wt
Wt
E188R
E188Q
401/402
E20R
GFP
MAGOH
rescue
protein:
aCADM2 RS-exon
KPNA1 RS-exon
mCADM2 RS-exon
eIF4A3
RS-exon
skipping (%)
400
300
EJC Knockdown and Rescue
of annotated RS-exon inclusion
eIF4A3 tethering to the exon
preceding the RS-exon
RS-exon
skipping (%) 0 12 0 17 0 19 22 0 26
RS-exon
skipping (%) 0 3 0 3 0 8 4 0 5
EJC
GT
GT
Flag
RS-5ss
MS2
MS2
MS2
A
B A EJC Depletion Leads to Inclusion of Cryptic Microexons To understand if the distance between eIF4A3 binding and
RS-5ss affects RS repression, we moved the SL2 sequence in
the mCADM2 splicing reporter from 20 nt to 28, 36, or 44 nt up-
stream of the exon-exon junction (Figure 5A). Co-expression of
MS2-eIF4A3 led to mCADM2 cryptic RS-exon inclusion in all
cases, although increasing the distance gradually diminished
the repressive capacity of eIF4A3 (Figures 5A and S5A). There-
fore, we hypothesized that the endogenous EJC could repress
a cryptic splice site also if it is located a few nucleotides away
from the exon-exon junction. For example, if an internal 5ss
was present within the first 15 nt of a long exon, then its recursive
recognition would result in inclusion of a short exon that could be
considered a microexon (defined as any exon shorter than 15 nt;
Irimia et al., 2014). To test this hypothesis, we shifted the position
of the RS-5ss in KPNA1 6 nt downstream of the exon-exon junc-
tion. In the unspliced reporter, this internal 5ss was repressed,
but in the part-spliced reporter, it was used, leading to inclusion
of a 6-nt microexon (Figures 5B and S5B). In agreement, eIF4A3
KD also increased the use of internal cryptic 5ss and led to MAGOH-RBM8A proteins stabilize eIF4A3 binding to RNA by
inhibiting its ATPase activity (Ballut et al., 2005; Gehring et al.,
2009). Thus, we asked if eIF4A3 could repress RS when stably
tethered to RNA, even if it is incapable of assembling an EJC. EJC Depletion Leads to Inclusion of Cryptic Microexons We designed a KPNA1 unspliced tethering reporter in which
the EJC deposition site was substituted by one MS2 bacterio-
phage stem loop 2 (SL2) and co-expressed the MS2 coat protein 502
Molecular Cell 72, 496–509, November 1, 2018 RS-5ss
MS2
20nt
RS-5ss
MS2
28nt
RS-5ss
MS2
36nt
RS-5ss
MS2
44nt
400
500
Micro Unspliced (uUnsp)
Wild-type
Micro Part-spliced (uPart)
GT
Internal 5ss containing
KPNA1 Part-spliced reporter
600
400
500
uUnsp uPart
KD
Ctrl
Wt
Mut
eIF4A3 Ctrl
eIF4A3
SL2-Wt
MS2
eIF4A3
MS2
eIF4A3
SL2-28
GFP
GFP
GFP
Internal 5ss use
RS-5ss use
GFP
MS2
eIF4A3
MS2
eIF4A3
SL2-36
SL2-44
dPURS
300
500
200
100
BRIP1
TSPAN4
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
200
300
100
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
RS-exon
skipping (%) 82 24 81 33 79 35 80 51
Tethered
protein:
Splicing
reporter:
eIF4A3 tethering to the exon
preceding mCADM2 RS-exon
Internal 5ss containing KPNA1 Unspliced Reporter
Internal 5ss Mut
Canonical 5ss Mut
EJC
EJC
−30
−20
−10
0
10
20
30
0 8 0 0
0 12 9 10 0
Microexon
inclusion (%)
Microexon
inclusion (%)
3 23 19 27 4
Microexon
inclusion (%)
Microexon
inclusion (%)
0 98
GT
GT
GT
internal 5ss Mut
EJC
EJC
GC
GC
GT
1-15nt
Wild-type
600
400
500
KD
Ctrl
Wt
Mut
eIF4A3 Ctrl
eIF4A3
EJC
EJC
1 13 0 0
Microexon
inclusion (%)
GT GT
GT GT
canonical 5ss Mut
EJC
EJC
AT
GT
6-nt
6-nt GT
A
C
D
E
B
cryptic microexons
RS-exons
Figure 5. EJC Depletion Leads to Inclusion of Cryptic Microexons
(A) The SL2 in mCADM2 splicing reporter was moved upstream of the exon-exon junction as indicated, and the RS-exon splicing pattern was analyzed after c
transfection of SL2 reporters and plasmids expressing MS2-eIF4A3 or GFP proteins. (B) Six nucleotides (GCACAG) were added at the beginning of the KPNA1 RS-exon to move the RS site to an internal 5ss, thus creating a KPNA1 microex
reporter. Unspliced and part-spliced version of the reporters were transfected, and their splicing pattern was analyzed by RT-PCR. (C) The internal or canonical 5ss within KPNA1 microexon unspliced reporter were mutated, and the splicing pattern was analyzed by RT-PCR after transfecti
into HeLa cells treated with control or eIF4A3 siRNAs. (D) The difference in the use of RS-5ss or internal 5ss in EJC KD compared to control (dPURS) is shown in HeLa cells. EJC Depletion Leads to Inclusion of Cryptic Microexons Cryptic microexons result from the use of
internal 5ss that is located within the first 15 nt of a longer annotated exon. Positive dPURS values indicate increased RS-exon skipping or increased inclusion
cryptic microexons. (E) RT-PCR validation of 2 microexon inclusion events identified in (D) after KD of EJC core factors or UPF1. Results shown in (A)–(C) and (E) derive from a minimum of 3 independent replicates performed in HeLa cells. EJC Depletion Leads to Inclusion of Cryptic Microexons RS-5ss
MS2
20nt
RS-5ss
MS2
28nt
RS-5ss
MS2
36nt
RS-5ss
MS2
44nt
400
500
Micro Unspliced (uUnsp)
Micro Part-spliced (uPart)
GT
Internal 5ss containing
KPNA1 Part-spliced reporter
uUnsp uPart
SL2-Wt
MS2
eIF4A3
MS2
eIF4A3
SL2-28
GFP
GFP
GFP
GFP
MS2
eIF4A3
MS2
eIF4A3
SL2-36
SL2-44
RS-exon
skipping (%) 82 24 81 33 79 35 80 51
Tethered
protein:
Splicing
reporter:
eIF4A3 tethering to the exon
preceding mCADM2 RS-exon
Microexon
inclusion (%)
0 98
6-nt
6-nt GT
A
B RS-5ss
MS2
20nt
RS-5ss
MS2
28nt
RS-5ss
MS2
36nt
RS-5ss
MS2
44nt
400
500
SL2-Wt
MS2
eIF4A3
MS2
eIF4A3
SL2-28
GFP
GFP
GFP
GFP
MS2
eIF4A3
MS2
eIF4A3
SL2-36
SL2-44
RS-exon
skipping (%) 82 24 81 33 79 35 80 51
Tethered
protein:
Splicing
reporter:
eIF4A3 tethering to the exon
preceding mCADM2 RS-exon
A
B A B Micro Unspliced (uUnsp)
Micro Part-spliced (uPart)
GT
Internal 5ss containing
KPNA1 Part-spliced reporter
uUnsp uPart
Microexon
inclusion (%)
0 98
6-nt
6-nt GT Wild-type
600
400
500
KD
Ctrl
Wt
Mut
eIF4A3 Ctrl
eIF4A3
Internal 5ss containin
Internal 5ss Mut
EJC
EJC
0 8 0 0
Microexon
inclusion (%)
GT
GT
internal 5ss Mut
EJC
EJC
GC
GC
C Wild-type
600
400
500
KD
Ctrl
Wt
Mut
eIF4A3 Ctrl
eIF4A3
Internal 5ss containing KPNA1 Unspliced Reporter
Internal 5ss Mut
Canonical 5ss Mut
EJC
EJC
0 8 0 0
Microexon
inclusion (%)
GT
GT
internal 5ss Mut
EJC
EJC
GC
GC
Wild-type
600
400
500
KD
Ctrl
Wt
Mut
eIF4A3 Ctrl
eIF4A3
EJC
EJC
1 13 0 0
Microexon
inclusion (%)
GT GT
GT GT
canonical 5ss Mut
EJC
EJC
AT
GT
C Internal 5ss containing KPNA1 Unspliced Reporter C Canonical 5ss Mut
Wild-type
600
400
500
KD
Ctrl
Wt
Mut
eIF4A3 Ctrl
eIF4A3
EJC
EJC
1 13 0 0
Microexon
inclusion (%)
GT GT
GT GT
canonical 5ss Mut
EJC
EJC
AT
GT Canonical 5ss Mut Canonical 5ss Mut 300
500
200
100
BRIP1
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
0 12 9 10 0
Microexon
inclusion (%)
E TSPAN4
200
300
100
KD
eIF4A3
Ctrl
MAGOH
UPF1
RBM8A
3 23 19 27 4
Microexon
inclusion (%) Internal 5ss use
RS-5ss use
dPURS
−30
−20
−10
0
10
20
30
GT
GT
1-15nt
D
cryptic microexons
RS-exons E D TSPAN4 Figure 5. EJC Depletion Leads to Inclusion of Cryptic Microexons Figure 5. Molecular Cell 72, 496–509, November 1, 2018
503 EJC Depletion Leads to Inclusion of Cryptic Microexons EJC Depletion Leads to Inclusion of Cryptic Microexons
(A) The SL2 in mCADM2 splicing reporter was moved upstream of the exon-exon junction as indicated, and the RS-exon splicing pattern was analyzed after co-
transfection of SL2 reporters and plasmids expressing MS2-eIF4A3 or GFP proteins. (B) Six nucleotides (GCACAG) were added at the beginning of the KPNA1 RS-exon to move the RS site to an internal 5ss, thus creating a KPNA1 microexon
reporter. Unspliced and part-spliced version of the reporters were transfected, and their splicing pattern was analyzed by RT-PCR. (C) The internal or canonical 5ss within KPNA1 microexon unspliced reporter were mutated, and the splicing pattern was analyzed by RT-PCR after transfection
into HeLa cells treated with control or eIF4A3 siRNAs. (D) The difference in the use of RS-5ss or internal 5ss in EJC KD compared to control (dPURS) is shown in HeLa cells. Cryptic microexons result from the use of an
internal 5ss that is located within the first 15 nt of a longer annotated exon. Positive dPURS values indicate increased RS-exon skipping or increased inclusion of
cryptic microexons. (E) RT-PCR validation of 2 microexon inclusion events identified in (D) after KD of EJC core factors or UPF1 g
(A) The SL2 in mCADM2 splicing reporter was moved upstream of the exon-exon junction as indicated, and the RS-exon splicing pattern was analyzed after co-
transfection of SL2 reporters and plasmids expressing MS2-eIF4A3 or GFP proteins. (B) Six nucleotides (GCACAG) were added at the beginning of the KPNA1 RS-exon to move the RS site to an internal 5ss, thus creating a KPNA1 microexon
reporter. Unspliced and part-spliced version of the reporters were transfected, and their splicing pattern was analyzed by RT-PCR. (C) The internal or canonical 5ss within KPNA1 microexon unspliced reporter were mutated, and the splicing pattern was analyzed by RT-PCR after transfection
into HeLa cells treated with control or eIF4A3 siRNAs. (D) The difference in the use of RS-5ss or internal 5ss in EJC KD compared to control (dPURS) is shown in HeLa cells Cryptic microexons result from the use of an (E) RT-PCR validation of 2 microexon inclusion events identified in (D) after KD of EJC core factors or UPF1. Results shown in (A)–(C) and (E) derive from a minimum of 3 independent replicates performed in HeLa cells. (E) RT-PCR validation of 2 microexon inclusion events identified in (D) after KD of EJC core factors or UPF1. EJC-Mediated Repression of RS in the Brain p
Mutations and copy-number variations in RBM8A and EIF4A3
genes are associated with neurodevelopmental phenotypes
(Bartkowska et al., 2018). Moreover, haploinsufficiency of
Rbm8a or Magoh in mice results in microcephaly (Mao et al.,
2016). To understand if lower levels of EJC would lead to RS
in the brain, we analyzed RNA-seq data from Magoh haploinsuf-
ficient mouse brain (MagohMos2/+). Highly included RS-exons in
wild-type brain (PSI > 90%) showed increased skipping in the
brain of Magoh haploinsufficient mice (Figure 6A), but not in
control mice (Figure 6B). RT-PCR analysis validated 4 of these
RS-exon skipping events in neuronal precursor cells (NPCs)
derived from mouse embryonic stem cells (mESCs) that were
transduced with shRNAs targeting Eif4a3, Magoh, or Rbm8a
genes (Figures S6A–S6C). Importantly, two of the validated
genes have previously been associated with microcephaly
(Faheem et al., 2015). Since EJC happloinsuficiency primarily
manifests a developmental brain phenotype, we wondered if
the greater sensitivity of the brain tissue may reflect variable
abundance of EJC components between tissues. Indeed, the
expression level of EIF4A3 and MAGOH mRNAs, as determined
from genotype tissue expression (GTEx) data, is much lower in
brain and muscle than in blood, lung, and breast, which sug-
gests that a variation in functional EJC assembly might lead to
physiological variations in the AS of RS-exons across tissues
(Figure S6D). Inclusion of RS-Exons Increased Across Evolution Finally, we wished to assess the potential for RS mechanism in
regulating putative RS-exons across evolutionarily divergent
species. To adjust the threshold for RS-5ss score to each spe-
cies, we analyzed the distribution of canonical 5ss scores at
exon-intron junctions of all internal exons annotated in 7 different
species. We defined the 5ss score that includes 90% of all ca-
nonical 5ss in each species and then classified putative RS-
exons that reconstitute a RS-5ss above this score (Figures 7A
and 7B). All examined species from the deuterostome clade,
from sea urchin to human, have a similar proportion of annotated
RS-exons, whereas the proportion decreases approximately
2-fold in Drosophila and yeast (Figure 7B). The lower number
of annotated RS-exons contrasts the large number of efficient in-
tronic RS sites, which are more common in Drosophila (n = 197)
than humans (n = 10) (Duff et al., 2015; Sibley et al., 2015). RS Leads to Physiological AS of RS-Exons RS Leads to Physiological AS of RS-Exons whole-exon skipping both in control and eIF4A3-depleted cells. This is consistent with the two-step model of splicing regulation
(Figure 1A), where the canonical 5ss is needed for exon definition
that initiates the first step of splicing and competition between
the two 5ss takes place only in the part-spliced transcript to
determine whether the microexon or the full exon will be
chosen during the second step of splicing. When EJC deposition
inhibits recognition of the internal 5ss, inclusion of the cryptic
microexon is repressed, thus ensuring that the annotated exon
is fully included. To gain insight into the role that RS plays in the AS of RS-exons,
we returned to a more detailed analysis of PRPF8 crosslinking. In control cells, PRPF8 iCLIP revealed a crosslinking peak
12–14 nt upstream of exon-exon junctions formed by RS-exons,
which was significantly higher when compared to non RS-exons
(Figure 3B; independent samples t-test, p = 0.0016, t = 3.167). This indicates that some RS-exons can assemble spliceosome
on the RS-5ss in the presence of EJC under physiological condi-
tions. This is illustrated in the MRPS5 gene, where a sharp peak
of PRPF8 crosslinks is apparent upstream of the RS-exon both
in control and eIF4A3 KD conditions and is accompanied by
RS-exon skipping in RNA-seq (Figure 6C). In order to understand the global role of the EJC in the repres-
sion of cryptic microexons hosted by annotated exons, we first
identified exons expressed in HeLa cells that either reconstitute
a 5ss exactly at the exon-exon junction (putative RS-exons,
n = 1,105) or up to 15 nt from the beginning of the exons (puta-
tive cryptic microexons, n = 545). We analyzed the splicing
pattern of RS-exons and cryptic microexons upon EJC deple-
tion and measured the difference in the use of RS-5ss
or internal 5ss in EJC KD compared to control (dPURS). In
RS-exons, a positive dPURS indicates increased skipping due
to use of RS-5ss, whereas in cryptic microexons, it indicates
increased inclusion due to use of the internal 5ss. eIF4A3 KD
led to increased skipping in 26.8% of RS-exons, as expected
from previous results, but also to inclusion of 5.3% of cryptic
microexons (dPURS R 10) (Figure 5D). Interestingly, the distri-
bution of internal 5ss MaxEntScan scores in cryptic microexons
was very similar to the distribution of RS-5ss MaxEntScan
scores in RS-exons (Figure S5D). RS Leads to Physiological AS of RS-Exons RT-PCR analysis validated
the inclusion for two of these cryptic microexons in HeLa
cells depleted of core EJC factors, but not UPF1 (Figures 5E
and S5E). As an alternative approach to directly monitor RS, we exam-
ined the lariat-spanning reads that are present in total RNA-
seq data by following previously established methods (Pineda
and Bradley, 2018). Previous studies have focused on exon-
inclusion lariats, where the sequence at the start of the intron
is connected to the sequence upstream of the branchpoint
(BP). Here, we searched for recursive-splicing lariats (RS-lariats),
which arise from introns that link the 50 end of an exon to the BP
(Figure 6D). We identified 287 high-confidence pairings between
the BP and the start of a preceding exon (putative RS-lariats;
Table S6). We required reads supporting these high-confidence
pairings to have a single mismatch lying at the inferred BP loca-
tion, a stringent criterion that we previously found to be essential
for accurate BP inference (Pineda and Bradley, 2018). These
putative RS-lariats exhibited >4-fold enrichment for the –GU
dinucleotide at the start of the exons containing such lariats,
indicating that many of them likely reflect RS events. Approxi-
mately 44% of RS-lariats had adenine BPs, consistent with our
previous observation that BPs corresponding to AS exhibited a
decreased adenine frequency relative to those corresponding
to constitutive splicing (Pineda and Bradley, 2018). In the RS-
exon of AP1G2 gene, we experimentally confirmed the RS event
inferred by the computational analysis (Figures 6D and S6E). Taken together, PRPF8 iCLIP and analysis of splicing lariats
indicate that RS can represent a mechanism for AS under phys-
iological conditions. EJC Depletion Leads to Inclusion of Cryptic Microexons This is illustrated in the MRPS5 gene, where a sharp
of PRPF8 crosslinks is apparent upstream of the RS-exo
in control and eIF4A3 KD conditions and is accompan
RS-exon skipping in RNA-seq (Figure 6C). As an alternative approach to directly monitor RS, we
ined the lariat-spanning reads that are present in total
seq data by following previously established methods (P
and Bradley, 2018). Previous studies have focused on
inclusion lariats, where the sequence at the start of the
is connected to the sequence upstream of the branc
(BP). Here, we searched for recursive-splicing lariats (RS-la
which arise from introns that link the 50 end of an exon to t
(Figure 6D). We identified 287 high-confidence pairings be
the BP and the start of a preceding exon (putative RS-
Table S6). We required reads supporting these high-confi
pairings to have a single mismatch lying at the inferred BP
tion, a stringent criterion that we previously found to be es
for accurate BP inference (Pineda and Bradley, 2018). putative RS-lariats exhibited >4-fold enrichment for the
dinucleotide at the start of the exons containing such
indicating that many of them likely reflect RS events. Ap
mately 44% of RS-lariats had adenine BPs, consistent w
previous observation that BPs corresponding to AS exhib
decreased adenine frequency relative to those correspo
to constitutive splicing (Pineda and Bradley, 2018). In th
exon of AP1G2 gene, we experimentally confirmed the RS
inferred by the computational analysis (Figures 6D and
Taken together, PRPF8 iCLIP and analysis of splicing
indicate that RS can represent a mechanism for AS under
iological conditions. Inclusion of RS-Exons Increased Across Evolution
Finally, we wished to assess the potential for RS mechan
regulating putative RS exons across evolutionarily div EJC Depletion Leads to Inclusion of Cryptic Microexons eIF4A3 KD
led to increased skipping in 26.8% of RS-exons, as expected
from previous results, but also to inclusion of 5.3% of cryptic
microexons (dPURS R 10) (Figure 5D). Interestingly, the distri-
bution of internal 5ss MaxEntScan scores in cryptic microexons
was very similar to the distribution of RS-5ss MaxEntScan
scores in RS-exons (Figure S5D). RT-PCR analysis validated
the inclusion for two of these cryptic microexons in HeLa
cells depleted of core EJC factors, but not UPF1 (Figures 5E
and S5E). EJC-Mediated Repression of RS in the Brain
Mutations and copy-number variations in RBM8A and EIF4A3
RS Leads to Physiological AS of R
To gain insight into the role that RS pl
we returned to a more detailed analy
In control cells, PRPF8 iCLIP reve
12–14 nt upstream of exon-exon junct
which was significantly higher when c
(Figure 3B; independent samples t-te
This indicates that some RS-exons c
on the RS-5ss in the presence of EJC
tions. This is illustrated in the MRPS5
of PRPF8 crosslinks is apparent upst
in control and eIF4A3 KD conditions
RS-exon skipping in RNA-seq (Figure
As an alternative approach to direc
ined the lariat-spanning reads that
seq data by following previously est
and Bradley, 2018). Previous studie
inclusion lariats, where the sequence
is connected to the sequence upst
(BP). Here, we searched for recursive-
which arise from introns that link the 5
(Figure 6D). We identified 287 high-co
the BP and the start of a preceding
Table S6). We required reads support
pairings to have a single mismatch lyi
tion, a stringent criterion that we previ
for accurate BP inference (Pineda a
putative RS-lariats exhibited >4-fold
dinucleotide at the start of the exon
indicating that many of them likely re
mately 44% of RS-lariats had adenin
previous observation that BPs corres
decreased adenine frequency relativ
to constitutive splicing (Pineda and B whole-exon skipping both in control and eIF4A3-depleted cells. This is consistent with the two-step model of splicing regulation
(Figure 1A), where the canonical 5ss is needed for exon definition
that initiates the first step of splicing and competition between
the two 5ss takes place only in the part-spliced transcript to
determine whether the microexon or the full exon will be
chosen during the second step of splicing. When EJC deposition
inhibits recognition of the internal 5ss, inclusion of the cryptic
microexon is repressed, thus ensuring that the annotated exon
is fully included. EJC Depletion Leads to Inclusion of Cryptic Microexons In order to understand the global role of the EJC in the repres-
sion of cryptic microexons hosted by annotated exons, we first
identified exons expressed in HeLa cells that either reconstitute
a 5ss exactly at the exon-exon junction (putative RS-exons,
n = 1,105) or up to 15 nt from the beginning of the exons (puta-
tive cryptic microexons, n = 545). We analyzed the splicing
pattern of RS-exons and cryptic microexons upon EJC deple-
tion and measured the difference in the use of RS-5ss
or internal 5ss in EJC KD compared to control (dPURS). In
RS-exons, a positive dPURS indicates increased skipping due
to use of RS-5ss, whereas in cryptic microexons, it indicates
increased inclusion due to use of the internal 5ss. eIF4A3 KD
led to increased skipping in 26.8% of RS-exons, as expected
from previous results, but also to inclusion of 5.3% of cryptic
microexons (dPURS R 10) (Figure 5D). Interestingly, the distri-
bution of internal 5ss MaxEntScan scores in cryptic microexons
was very similar to the distribution of RS-5ss MaxEntScan
scores in RS-exons (Figure S5D). RT-PCR analysis validated
the inclusion for two of these cryptic microexons in HeLa
cells depleted of core EJC factors, but not UPF1 (Figures 5E
and S5E). EJC-Mediated Repression of RS in the Brain
Mutations and copy-number variations in RBM8A and EIF4A3
genes are associated with neurodevelopmental phenotypes
(Bartkowska et al., 2018). Moreover, haploinsufficiency of
Rbm8a or Magoh in mice results in microcephaly (Mao et al.,
2016). To understand if lower levels of EJC would lead to RS
in the brain, we analyzed RNA-seq data from Magoh haploinsuf-
ficient mouse brain (MagohMos2/+). Highly included RS-exons in
wild-type brain (PSI > 90%) showed increased skipping in the
brain of Magoh haploinsufficient mice (Figure 6A), but not in
control mice (Figure 6B) RT PCR analysis validated 4 of these
RS Leads to Physiological AS of RS-Exons
To gain insight into the role that RS plays in the AS of RS-e
we returned to a more detailed analysis of PRPF8 crossl
In control cells, PRPF8 iCLIP revealed a crosslinking
12–14 nt upstream of exon-exon junctions formed by RS-e
which was significantly higher when compared to non RS-
(Figure 3B; independent samples t-test, p = 0.0016, t = 3
This indicates that some RS-exons can assemble spliceo
on the RS-5ss in the presence of EJC under physiological
tions. EJC Depletion Leads to Inclusion of Cryptic Microexons Results shown in (A)–(C) and (E) derive from a minimum of 3 independent replicates performed in HeLa cells. our findings, we generated splicing reporters in which we
mutated either the internal or the canonical 5ss of the regulated
KPNA1 exon. As expected, the microexon was no longer
included after eIF4A3 KD when the internal 5ss was mutated. Importantly, mutation of canonical 5ss did not increase the
use of internal 5ss and microexon inclusion (Figures 5C and
S5C), which contradicts the standard model. Instead, it led to microexon inclusion (Figures 5C and S5C). This demonstrates
that EJC recruitment through the first step of splicing is crucial
to not only prevent RS-5ss but also repress other cryptic 5ss’s
located close to the exon-exon junction. According to the standard model of splicing regulation,
competition between alternative 5ss takes place during exon
definition in the pre-mRNA. To test if this model could explain Molecular Cell 72, 496–509, November 1, 2018
503 Molecular Cell 72, 496–509, November 1, 2018
503 whole-exon skipping both in control and eIF4A3-depleted cells. This is consistent with the two-step model of splicing regulation
(Figure 1A), where the canonical 5ss is needed for exon definition
that initiates the first step of splicing and competition between
the two 5ss takes place only in the part-spliced transcript to
determine whether the microexon or the full exon will be
chosen during the second step of splicing. When EJC deposition
inhibits recognition of the internal 5ss, inclusion of the cryptic
microexon is repressed, thus ensuring that the annotated exon
is fully included. In order to understand the global role of the EJC in the repres-
sion of cryptic microexons hosted by annotated exons, we first
identified exons expressed in HeLa cells that either reconstitute
a 5ss exactly at the exon-exon junction (putative RS-exons,
n = 1,105) or up to 15 nt from the beginning of the exons (puta-
tive cryptic microexons, n = 545). We analyzed the splicing
pattern of RS-exons and cryptic microexons upon EJC deple-
tion and measured the difference in the use of RS-5ss
or internal 5ss in EJC KD compared to control (dPURS). In
RS-exons, a positive dPURS indicates increased skipping due
to use of RS-5ss, whereas in cryptic microexons, it indicates
increased inclusion due to use of the internal 5ss. EJC-Mediated Repression of RS in the Brain To un-
derstand if RS sites in Drosophila might be linked to cryptic RS-
exons instead of annotated RS-exons, we examined previously 504
Molecular Cell 72, 496–509, November 1, 2018 A
B
−11
−8
−5
−2
1
4
7
10
dPSI
0.05
0.00
-0.05
-0.10
−11
−8
−5
−2
1
4
7
10
dPSI
RS-5ss
Magoh haploinsufficient mouse brain (MagohMos2/+)
Control mouse brain (Emx1-cre)
0.05
0.00
-0.05
-0.10
RS-5ss
RS-exon
PRPF8 iCLIP gapped
reads at RS-5ss
MRPS5
AP1G2 RS-exon
gapped
reads
15
0
15
0
ungapped
reads
Ctrl
KD
15
0
15
0
Ctrl
KD
RNAseq
Ctrl
RS-exon skipping
D
E
C
Std-lariat
Exon-inclusion
upstream lariat
RS-lariat
Exon-inclusion
downstream lariat
RS-exon
BP
BP
RS-lariat reads (32)
gtatgtagccctgacatcac.........gtgagcagtgatagagggga...agagggcctgaggcatggaccaggatgacctgggctacCtgcAtggaaacctctttctcctgccag
Exon inclusion
downstream lariats (3)
agagggcctgaggcatggaccaggatgacctgggctac-gtatgtagccctgacatcac
accaggatgacctgggctacTgtgagcagtgatagaggggacagga
accaggatgacctgggctacctgcTgtgagcagtgatagaggggacagga
agagggcctgaggcatggaccaggatgacctgggctacctgcTgtatgtagccctgacatcac
0
10
20
0
10
20
sequences
K562
cerebellum
18
13
1
ure 6. EJC-Mediated Repression of Recursive Splicing in the Brain, and Physiologic Recursive Splicing
he dPSI of exons highly included in wild-type mouse brain (PSI > 90%) is shown after comparison with Magoh haploinsufficient mouse brain as in Figure 1E. ame as (A), but comparing control Emx1-cre and wild-type mouse brain. schematic of the MRPS5 gene with the RS-exon highlighted in blue. Below, PRPF8 iCLIP crosslinking is shown, as identified by either ungapped or gapped
s in control or eIF4A3 KD cells (4 replicates are summed up per condition). Crosslinks upstream of junctions involving the RS-exon are shown in red, and
esponding reads are zoomed into on the right. Further below, a Sashimi plot shows RNA-seq evidence of RS-exon skipping. he types of possible lariats associated with RS-exon splicing are named. In black are the lariats that were detected for the AP1G2 gene as described in (E). equence of the RS-exon in the AP1G2 gene and its downstream intron. BP annotations based on lariat sequencing are highlighted in red. Arrows indicate
ers used to interrogate lariats shown in black in (D). Above, sequences and number of reads supporting RS-lariats (inverted alignment) with alternative BP
otations in cerebellum and K562 cells are shown. Below, sequences and number of reads supporting exon inclusion downstream lariats with alternative BP
otations are shown. EJC-Mediated Repression of RS in the Brain Contrary to human cells
and mouse brain respectively, we could not observe more skip-
ping of exons with high RS-5ss score upon EJC factor depletion
(Figure S7B). Thus, Drosophila contains a low number of ‘anno-
tated RS-exons’ and we could not find any evidence of their
sensitivity to EJC perturbation. This indicates that EJC assembly
might not play an important role in the repression of RS in EJC-Mediated Repression of RS in the Brain p
p
g
,
y
g
p
g
uded in wild-type mouse brain (PSI > 90%) is shown after comparison with Magoh haploinsufficient mouse brain as in Figure 1E. control Emx1-cre and wild-type mouse brain. g
p
p
g
y
g
p
g
(A) The dPSI of exons highly included in wild-type mouse brain (PSI > 90%) is shown after comparison with Magoh haploinsuffi
(B) Same as (A), but comparing control Emx1-cre and wild-type mouse brain. Drosophila, which could explain the large number of cryptic
RS-exons in Drosophila. defined Drosophila RS sites (Duff et al., 2015) to find that most of
them are followed by an additional 5ss less than 100 nt down-
stream of the RS site (Figure S7A). These downstream 5ss
tend to be more conserved than other 5ss-like sequences in
the same introns (Figure S7A), which indicates that they
contribute to the definition of cryptic RS-exons in Drosophila (Jo-
seph et al., 2018), similar to the mechanism of RS in vertebrates
(Sibley et al., 2015). To determine if RS of annotated RS-exons is
repressed by the EJC in Drosophila, we performed RNA-seq in
S2 cells treated with double-stranded RNAs (dsRNAs) against
mago, eIF4AIII, and LacZ as control. Contrary to human cells
and mouse brain respectively, we could not observe more skip-
ping of exons with high RS-5ss score upon EJC factor depletion
(Figure S7B). Thus, Drosophila contains a low number of ‘anno-
tated RS-exons’ and we could not find any evidence of their
sensitivity to EJC perturbation. This indicates that EJC assembly
might not play an important role in the repression of RS in defined Drosophila RS sites (Duff et al., 2015) to find that most of
them are followed by an additional 5ss less than 100 nt down-
stream of the RS site (Figure S7A). These downstream 5ss
tend to be more conserved than other 5ss-like sequences in
the same introns (Figure S7A), which indicates that they
contribute to the definition of cryptic RS-exons in Drosophila (Jo-
seph et al., 2018), similar to the mechanism of RS in vertebrates
(Sibley et al., 2015). To determine if RS of annotated RS-exons is
repressed by the EJC in Drosophila, we performed RNA-seq in
S2 cells treated with double-stranded RNAs (dsRNAs) against
mago, eIF4AIII, and LacZ as control. EJC-Mediated Repression of RS in the Brain A
0.05
0.00
-0.05
-0.10
−11
−8
−5
−2
1
4
7
10
dPSI
RS-5ss
Magoh haploinsufficient mouse brain (MagohMos2/+) RS-exon
PRPF8 iCLIP gapped
reads at RS-5ss
MRPS5
gapped
reads
15
0
15
0
ungapped
reads
Ctrl
KD
15
0
15
0
Ctrl
KD
RNAseq
Ctrl
RS-exon skipping
C C A B B
−11
−8
−5
−2
1
4
7
10
dPSI
Control mouse brain (Emx1-cre)
0.05
0.00
-0.05
-0.10
RS-5ss RNAseq AP1G2 RS-exon
D
E
Std-lariat
Exon-inclusion
upstream lariat
RS-lariat
Exon-inclusion
downstream lariat
RS-exon
BP
BP
RS-lariat reads (32)
gtatgtagccctgacatcac.........gtgagcagtgatagagggga...agagggcctgaggcatggaccaggatgacctgggctacCtgcAtggaaacctctttctcctgccag
Exon inclusion
downstream lariats (3)
agagggcctgaggcatggaccaggatgacctgggctac-gtatgtagccctgacatcac
accaggatgacctgggctacTgtgagcagtgatagaggggacagga
accaggatgacctgggctacctgcTgtgagcagtgatagaggggacagga
agagggcctgaggcatggaccaggatgacctgggctacctgcTgtatgtagccctgacatcac
0
10
20
0
10
20
sequences
K562
cerebellum
18
13
1 G2 RS-exon
E
RS-lariat reads (32)
gtagccctgacatcac.........gtgagcagtgatagagggga...agagggcctgaggcatggaccaggatgacctgggctacCtgcAtggaaacctctttctcctgccag
Exon inclusion
downstream lariats (3)
agagggcctgaggcatggaccaggatgacctgggctac-gtatgtagccctgacatcac
accaggatgacctgggctacTgtgagcagtgatagaggggacagga
accaggatgacctgggctacctgcTgtgagcagtgatagaggggacagga
agagggcctgaggcatggaccaggatgacctgggctacctgcTgtatgtagccctgacatcac
0
10
20
0
10
20
sequences
K562
cerebellum
18
13
1 D E Figure 6. EJC-Mediated Repression of Recursive Splicing in the Brain, and Physiologic Recursive Splicing Repression of Recursive Splicing in the Brain, and Physiologic Recursive Splicing e Splicing in the Brain, and Physiologic Recursive Splicin g
p
p
g
,
y
g
p
g
(A) The dPSI of exons highly included in wild-type mouse brain (PSI > 90%) is shown after comparison with Magoh haploinsufficient mouse brain as in Figure 1E. (B) Same as (A), but comparing control Emx1-cre and wild-type mouse brain. (C) A schematic of the MRPS5 gene with the RS-exon highlighted in blue. Below, PRPF8 iCLIP crosslinking is shown, as identified by either ungapped or gapped
reads in control or eIF4A3 KD cells (4 replicates are summed up per condition). Crosslinks upstream of junctions involving the RS-exon are shown in red, and
corresponding reads are zoomed into on the right. Further below, a Sashimi plot shows RNA-seq evidence of RS-exon skipping. (D) The types of possible lariats associated with RS-exon splicing are named. In black are the lariats that were detected for the AP1G2 gene as described in (E). (E) Sequence of the RS-exon in the AP1G2 gene and its downstream intron. BP annotations based on lariat sequencing are highlighted in red. Arrows indicate
primers used to interrogate lariats shown in black in (D). Above, sequences and number of reads supporting RS-lariats (inverted alignment) with alternative BP
annotations in cerebellum and K562 cells are shown. Below, sequences and number of reads supporting exon inclusion downstream lariats with alternative BP
annotations are shown. DISCUSSION Due to the large number of
RS-5ss in the transcriptome and their positioning next to the
EJC, RS-5ss are likely to be the primary target for EJC-depen-
dent repression, but as evidenced by the new class of EJC-
repressed microexons in our study and a parallel study (Boehm
et al., 2018), other types of cryptic splice sites can also be
repressed by the EJC in part-spliced transcripts. Conversely, stable tethering of assembly-deficient eIF4A3 alone
is also sufficient for repression, which indicates that assembly of
the whole EJC complex is required for its stable binding to RNA. We used PRPF8 iCLIP to confirm that upon EJC KD, spliceo-
some assembles at hundreds of RS-5ss that are formed by
RS-exons. In addition to blocking RS-5ss, EJC also blocks other
nearby 5ss, which leads to repression of cryptic microexons,
which are derived from the beginning of annotated exons. Anal-
ysis of EJC haploinsufficient mouse brain and putative RS-exons
across divergent species indicates that the function of the EJC in
the repression of RS-exons is likely to be broadly conserved
across deuterostomes. Conversely, stable tethering of assembly-deficient eIF4A3 alone
is also sufficient for repression, which indicates that assembly of
the whole EJC complex is required for its stable binding to RNA. We used PRPF8 iCLIP to confirm that upon EJC KD, spliceo-
some assembles at hundreds of RS-5ss that are formed by
RS-exons. In addition to blocking RS-5ss, EJC also blocks other
nearby 5ss, which leads to repression of cryptic microexons,
which are derived from the beginning of annotated exons. Anal-
ysis of EJC haploinsufficient mouse brain and putative RS-exons
across divergent species indicates that the function of the EJC in
the repression of RS-exons is likely to be broadly conserved
across deuterostomes. The EJC is the primary RNP deposited on spliced mRNAs, but
most functional studies of the EJC have focused on its cytosolic
role in premature termination codon recognition during NMD (Le
Hir et al., 2016). The role of the EJC in repressing hundreds of RS
events has opened a new opportunity to examine its nuclear
function from the moment the EJC starts assembling on the
partly spliced RNA (Figure 7). By using assembly-deficient mu-
tants of eIF4A3 and MAGOH, we found that these proteins
cannot individually bind to pre-mRNA to repress RS; instead, as-
sembly of the EJC, including the peripheral components PNN
and RNPS1, is required for the repressive capacity. DISCUSSION sapiens (human)
5.52
3.30%
D. rerio (zebrafish)
4.22
4.71%
P. marinus (lamprey)
2.93
4.69%
C. intestinalis (ciona)
3.59
5.47%
S. purpuratus (sea urchin)
5.96
3.15%
D. melanogaster (fruit fly)
5.1
1.96%
S. cerevisiae (yeast)
4.36
1.40%
exon-intron
junctions
exon-exon
junctions
RS-5ss threshold
for candidate
RS-exons
GT
GT
GT
GT
GT
A
C
B
Figure 7. Analysis of RS-Exon Inclusion
across Evolution
(A) Density plot showing 5ss score distribution at
exon-intron junctions (canonical 5ss, shaded lines)
or at exon-exon junctions (RS-5ss, unshaded
lines) for all internal annotated exons in human
(blue), sea urchin (purple), or fruit fly (green). The
red line represents the 5ss score is lower than 90%
of exon-intron junctions in each species. This
value is used as the RS-5ss threshold to quantify
the
proportion
of
putative
RS-exons
across
species in (B). (B) A RS-5ss threshold was calculated as ex-
plained in (A) for 7 different species. Putative RS-
exons for each species were calculated as the
proportion of annotated exons that reconstitute a
RS-5ss above the threshold. (C)
Model
for
EJC-dependent
repression
of
recursive splicing and microexon inclusion. Top
panel: annotated putative RS-exons (in blue) are
defined and spliced to their preceding exon to
reconstitute a 5ss (RS-5ss) at the exon-exon
junction, which leads to EJC deposition. Two
outcomes can result from the second step of
splicing: (1) the EJC does not efficiently repress
the RS-5ss, either because it is a very strong RS-
5ss or EJC assembly is deficient, and as a result,
the RS-exon is recursively spliced; or (2) the EJC
efficiently represses recursive splicing at most RS-
5ss that are present in human mRNAs, most often
leading to constitutive inclusion of RS-exons. Bottom panel: canonical exons that contain an
internal 5ss close to their beginning (in white and purple) are defined and spliced to their preceding exon. (3) This splicing event leads to EJC deposition, which
normally blocks the internal 5ss recognition, leading to an isoform that includes the full exon (bottom). However, if EJC does not repress the internal 5ss efficiently,
its recognition leads to inclusion of a microexon (in white), while the rest of the exon (in purple) is removed in the second splicing step. Figure 7. DISCUSSION Analysis of RS-Exon Inclusion
across Evolution B A (A) Density plot showing 5ss score distribution at
exon-intron junctions (canonical 5ss, shaded lines)
or at exon-exon junctions (RS-5ss, unshaded
lines) for all internal annotated exons in human
(blue), sea urchin (purple), or fruit fly (green). The
red line represents the 5ss score is lower than 90%
of exon-intron junctions in each species. This
value is used as the RS-5ss threshold to quantify
the
proportion
of
putative
RS-exons
across
species in (B). (B) A RS-5ss threshold was calculated as ex-
plained in (A) for 7 different species. Putative RS-
exons for each species were calculated as the
proportion of annotated exons that reconstitute a
RS-5ss above the threshold. EJC-
5ss
RS-5ss
RS-5ss
<
EJC
-
5ss
>
EJC -
5ss
Internal 5ss
1
2
3
GT
GT
GT
GT
GT
C C Bottom panel: canonical exons that contain an
internal 5ss close to their beginning (in white and purple) are defined and spliced to their preceding exon. (3) This splicing event leads to EJC deposition, which
normally blocks the internal 5ss recognition, leading to an isoform that includes the full exon (bottom). However, if EJC does not repress the internal 5ss efficiently,
its recognition leads to inclusion of a microexon (in white), while the rest of the exon (in purple) is removed in the second splicing step. Instead, the EJC acts as a negative splicing factor by blocking
spliceosome assembly at the RS-5ss reconstituted at the
exon-exon junctions upstream of RS-exons. By repressing
hundreds of RS-5ss, the EJC plays a major role in preserving
transcriptome integrity in humans. Due to the large number of
RS-5ss in the transcriptome and their positioning next to the
EJC, RS-5ss are likely to be the primary target for EJC-depen-
dent repression, but as evidenced by the new class of EJC-
repressed microexons in our study and a parallel study (Boehm
et al., 2018), other types of cryptic splice sites can also be
repressed by the EJC in part-spliced transcripts. Instead, the EJC acts as a negative splicing factor by blocking
spliceosome assembly at the RS-5ss reconstituted at the
exon-exon junctions upstream of RS-exons. By repressing
hundreds of RS-5ss, the EJC plays a major role in preserving
transcriptome integrity in humans. DISCUSSION In this study, we find that the human transcriptome contains hun-
dreds of constitutive and alternative exons with RS-exon fea-
tures. This observation can be explained by the fact that GT is
the most common dinucleotide at exons starts (Sibley et al.,
2016) and that the ends of exons are enriched for nucleotides
compatible with 5ss. Once these ‘‘putative’’ RS-exons have
been spliced to the preceding exon, they reconstitute a RS-5ss
and thus gain the potential to be recursively spliced. However,
splicing-dependent deposition of EJC efficiently represses RS
of RS-exons, thus ensuring their efficient inclusion into mRNAs. Notably, all core EJC factors and the peripheral factors PNN and
RNPS1 are required for this repressive function of the EJC. Molecular Cell 72, 496–509, November 1, 2018
505 RS-exon that reconstitutes RS-5ss at its start
5’ splice site factors
3’ splice site factors
the core EJC factors
peripheral EJC factors (PNN and RNPS1)
a microexon that emerges upon use of an internal 5ss
Canonical exon with an internal 5ss close to its start
Other exons
EJC-
5ss
RS-5ss
RS-5ss
<
EJC
EJC
-
5ss
>
EJC -
5ss
Internal 5ss
1
2
3
0
2
4
6
−30
−20
−10
0
10
5ss MaxEntScan score
density at exon-exon junctions (%)
density at exon-intron junctions (%)
exon-intron junctions
(canonical 5ss)
exon-exon junctions
(RS-5ss)
0
5
10
15
20
D. melanogaster
H. sapiens
S. purpuratus
D. melanogaster
H. sapiens
S. purpuratus
Species
RS-5ss threshold
for candidate
RS-exons
Proportion of exons
with RS-5ss
above threshold
H. sapiens (human)
5.52
3.30%
D. rerio (zebrafish)
4.22
4.71%
P. marinus (lamprey)
2.93
4.69%
C. intestinalis (ciona)
3.59
5.47%
S. purpuratus (sea urchin)
5.96
3.15%
D. melanogaster (fruit fly)
5.1
1.96%
S. cerevisiae (yeast)
4.36
1.40%
exon-intron
junctions
exon-exon
junctions
RS-5ss threshold
for candidate
RS-exons
GT
GT
GT
GT
GT
A
C
B
Figure 7. Analysis of RS-Exon Inclusion
across Evolution
(A) Density plot showing 5ss score distribution at
exon-intron junctions (canonical 5ss, shaded lines)
or at exon-exon junctions (RS-5ss, unshaded
lines) for all internal annotated exons in human
(blue), sea urchin (purple), or fruit fly (green). The
red line represents the 5ss score is lower than 90%
of exon-intron junctions in each species. This
value is used as the RS-5ss threshold to quantify
the
proportion
of
putative
RS-exons
across
species in (B). (B) A RS-5ss threshold was calculated as ex-
plained in (A) for 7 different species. DISCUSSION However,
stable tethering of an assembly-deficient eIF4A3 mutant (401/
402) is sufficient to repress RS. This confirms the previous find-
ings that endogenous eIF4A3 needs to assemble the whole EJC
in order to achieve stable binding (Gehring et al., 2009). If stable DISCUSSION Putative RS-
exons for each species were calculated as the
proportion of annotated exons that reconstitute a
RS-5ss above the threshold. (C)
Model
for
EJC-dependent
repression
of
recursive splicing and microexon inclusion. Top
panel: annotated putative RS-exons (in blue) are
defined and spliced to their preceding exon to
reconstitute a 5ss (RS-5ss) at the exon-exon
junction, which leads to EJC deposition. Two
outcomes can result from the second step of
splicing: (1) the EJC does not efficiently repress
the RS-5ss, either because it is a very strong RS-
5ss or EJC assembly is deficient, and as a result,
the RS-exon is recursively spliced; or (2) the EJC
efficiently represses recursive splicing at most RS-
5ss that are present in human mRNAs, most often
leading to constitutive inclusion of RS-exons. Bottom panel: canonical exons that contain an
internal 5ss close to their beginning (in white and purple) are defined and spliced to their preceding exon. (3) This splicing event leads to EJC deposition, which
normally blocks the internal 5ss recognition, leading to an isoform that includes the full exon (bottom). However, if EJC does not repress the internal 5ss efficiently,
its recognition leads to inclusion of a microexon (in white), while the rest of the exon (in purple) is removed in the second splicing step. 0
2
4
6
−30
−20
−10
0
10
5ss MaxEntScan score
density at exon-exon junctions (%)
density at exon-intron junctions (%)
exon-intron junctions
(canonical 5ss)
exon-exon junctions
(RS-5ss)
0
5
10
15
20
D. melanogaster
H. sapiens
S. purpuratus
D. melanogaster
H. sapiens
S. purpuratus
exon-intron
junctions
exon-exon
junctions
RS-5ss threshold
for candidate
RS-exons
A
B RS-exon that reconstitutes RS-5ss at its start
5’ splice site factors
3’ splice site factors
the core EJC factors
peripheral EJC factors (PNN and RNPS1)
a microexon that emerges upon use of an internal 5ss
Canonical exon with an internal 5ss close to its start
Other exons
EJC-
5ss
RS-5ss
RS-5ss
<
EJC
EJC
-
5ss
>
EJC -
5ss
Internal 5ss
1
2
3
0
2
4
6
−30
−20
−10
0
10
5ss MaxEntScan score
density at exon-exon junctions (%)
density at exon-intron junctions (%)
exon-intron junctions
(canonical 5ss)
exon-exon junctions
(RS-5ss)
0
5
10
15
20
D. melanogaster
H. sapiens
S. purpuratus
D. melanogaster
H. sapiens
S. purpuratus
Species
RS-5ss threshold
for candidate
RS-exons
Proportion of exons
with RS-5ss
above threshold
H. Repression of RS Since EJC deposition is not sequence dependent, it has been
challenging to explain how it could regulate specific mRNAs. We now reveal a mechanism that provides insight into how the
exonic sequences define the splicing functions of the EJC (i.e.,
its role in repressing the widespread presence of RS-5ss that
are formed at junctions of specific exons in over a thousand
mRNAs). In contrast to known splicing regulators, which pro-
mote inclusion of weak exons by increasing their definition, the
EJC does not regulate definition or initial splicing of RS-exons. In fact, 5ss and 3ss scores of RS-exons are equal to or higher
than those of non RS constitutive exons (data not shown). 506
Molecular Cell 72, 496–509, November 1, 2018 binding is achieved artificially via the MS2 system, then it can
repress RS independently of the EJC. factors across different tissues from GTEx data suggests their
protein abundance is likely to vary across cell types, and addi-
tionally, the assembly of EJC at individual junctions could be
regulated in an exon-specific manner by factors such as SR pro-
teins (Singh et al., 2012). Moreover, we identified two RS-exons
that are more sensitive to depletion of RNPS1 and PNN than the
core EJC factors. Such exons could be affected by differential
activities of the peripheral factors, which could be regulated by
post-translational modifications or mutually exclusive binding,
such as the binding of PNN or ACIN1 to RNPS1 (Murachelli
et al., 2012). It has also been shown that EJC binding can be
affected by RNA secondary structures (Mishler et al., 2008;
Singh et al., 2012). It remains to be seen if these variables might
affect the efficiency of the EJC in blocking RS and if the release
from EJC repression could serve as a mechanism for regulating
the physiological AS of specific RS-exons. The second mechanistic question addresses why specific
RS-exons are more prone to RS than others. We found that
EJC-sensitive RS-exons have a preferential splicing order
compared to other exons, with an increased propensity to
have their upstream intron spliced first. This is consistent with
the trend for slightly stronger 3ss at EJC-sensitive RS-exons
compared to non sensitive exons, which could increase the
splicing kinetics of the preceding intron, and slightly weaker
5ss, which could decrease the splicing kinetics of the following
intron. STAR+METHODS Detailed methods are provided in the online version of this paper
and include the following: d KEY RESOURCES TABLE
d CONTACT FOR REAGENT AND RESOURCE SHARING
d EXPERIMENTAL MODEL AND SUBJECT DETAILS
d METHOD DETAILS
B Experimental methods
B Computational Analyses
d QUANTIFICATION AND STATISTICAL ANALYSIS
d DATA AND SOFTWARE AVAILABILITY
B Public RNA-seq data B Computational Analyses
d QUANTIFICATION AND STATISTICAL ANALYSIS d QUANTIFICATION AND STATISTICAL ANALYSIS d DATA AND SOFTWARE AVAILABILITY d DATA AND SOFTWARE AVAILABILITY
B Public RNA-seq data B Public RNA-seq data SUPPLEMENTAL INFORMATION We identified hundreds of EJC-sensitive RS-exons in HeLa
cells, and it is likely that the EJC plays a role in regulating
many additional alternative RS-exons in various cell types. An
important question for future research will be to understand if
the capacity of the EJC to promote RS-exon inclusion might
vary during development or between cell types, which would
be plausible for several reasons. The expression level of EJC Supplemental Information includes seven figures and seven tables and can be
found with this article online at https://doi.org/10.1016/j.molcel.2018.09.033. The Function of RS Regulation during Development g
g
p
While it is clear that the regulation of exon definition is respon-
sible for most AS, we now demonstrate that RS also contributes
to the physiological regulation of AS. PRPF8 iCLIP reveals spli-
ceosomal recognition of RS-5ss formed by specific alternative
RS-exons in unperturbed cells, without any depletion of EJC
components. Moreover, we provide further evidence in support
of endogenous RS by analysis of lariat-spanning reads from
RNA-seq and their validation with PCR. Analysis of RNA-seq
data from Magoh haploinsufficient mouse brain also shows
that the role of the EJC in repressing RS-exon skipping is
conserved at least from mouse to humans, if not more broadly. The analysis of genes affected by RS-exon skipping events in
the brain might also provide a clue into the microcephaly
phenotype of this mouse model. Genes that contain abnormally
skipped RS-exons in Magoh haploinsufficient brain include
Aspm and Cenpj, two genes previously associated with auto-
somal-recessive microcephaly that encode proteins essential
for mitotic cell progression during embryonic neurogenesis
(Faheem et al., 2015). Repression of RS This preferential splicing order is also consistent with the
expectation that RS is only possible if the upstream intron is
spliced first to create the RS-5ss that is then used for the
second splicing step. If the repressive capacity of the EJC
may not sufficient to repress the RS-5ss, then the RS-exon is
alternatively spliced or fully skipped through RS (Figure 7C, 1). However, most human putative RS-exons are constitutively
included, and many are dependent on the EJC for their inclusion
(Figure 7C, 2). A third possibility involves the presence of an in-
ternal 5ss close to the beginning of exons, which is within the
range of EJC repression; upon perturbation of the EJC, recog-
nition of the internal 5ss leads to inclusion of a cryptic micro-
exon (Figure 7C, 3). These appear to be mechanistically distinct
from the previously studied microexons, which are defined
before the first step of splicing by proteins such as nSR100
(Irimia
et
al.,
2014). Inclusion
of
cryptic
microexons
is regulated at the level of the part-spliced transcript, where
absence of the EJC causes the splicing machinery to reposition
from the canonical to the internal 5ss of the host exon. y
Repression Our results indicate that the efficiency of EJC-dependent
repression of RS might have increased in the evolution of deu-
terostomes, as evident by comparison of a perturbed EJC on
RS-exons in Drosophila, mouse, and human. This is consistent
with the increased proportion of RS-exons in the transcriptomes
of deuterostomes. Our experiments with mutant splicing re-
porters demonstrate that a single point mutation in the RS-5ss
can be sufficient to convert a cryptic RS-exon into an alternative
or constitutive exon. While such mutations could contribute to
the evolution of EJC-regulated RS-exons, they could also lead
to disease by activating inclusion of aberrant cryptic exons. We also found that mutations that increase the strength of RS-
5ss can increase the skipping of canonical exons, which should
be taken into account when interpreting the mechanisms of dis-
ease-causing mutations that are located near the start of exons. REFERENCES Le Hir, H., Saulie` re, J., and Wang, Z. (2016). The exon junction complex as a
node of post-transcriptional networks. Nat. Rev. Mol. Cell Biol. 17, 41–54. Aerne, B.L., Gailite, I., Sims, D., and Tapon, N. (2015). Hippo stabilises its
adaptor Salvador by antagonising the HECT ubiquitin ligase Herc4. PLoS
ONE 10, e0131113. Mao, H., McMahon, J.J., Tsai, Y.-H., Wang, Z., and Silver, D.L. (2016). Haploinsufficiency for core exon junction complex components disrupts em-
bryonic neurogenesis and causes p53-mediated microcephaly. PLoS Genet. 12, e1006282. Ashton-Beaucage, D., Udell, C.M., Lavoie, H., Baril, C., Lefranc¸ ois, M.,
Chagnon, P., Gendron, P., Caron-Lizotte, O., Bonneil, E., Thibault, P., and
Therrien, M. (2010). The exon junction complex controls the splicing of
MAPK and other long intron-containing transcripts in Drosophila. Cell 143,
251–262. Ashton-Beaucage, D., Udell, C.M., Lavoie, H., Baril, C., Lefranc¸ ois, M.,
Chagnon, P., Gendron, P., Caron-Lizotte, O., Bonneil, E., Thibault, P., and Therrien, M. (2010). The exon junction complex controls the splicing of
MAPK and other long intron-containing transcripts in Drosophila. Cell 143,
251–262. Mercer, T.R., Clark, M.B., Andersen, S.B., Brunck, M.E., Haerty, W., Crawford,
J., Taft, R.J., Nielsen, L.K., Dinger, M.E., and Mattick, J.S. (2015). Genome-
wide discovery of human splicing branchpoints. Genome Res. 25, 290–303. Ballut, L., Marchadier, B., Baguet, A., Tomasetto, C., Se´ raphin, B., and Le Hir,
H. (2005). The exon junction core complex is locked onto RNA by inhibition of
eIF4AIII ATPase activity. Nat. Struct. Mol. Biol. 12, 861–869. Michelle, L., Cloutier, A., Toutant, J., Shkreta, L., Thibault, P., Durand, M.,
Garneau, D., Gendron, D., Lapointe, E., Couture, S., et al. (2012). Proteins
associated with the exon junction complex also control the alternative splicing
of apoptotic regulators. Mol. Cell. Biol. 32, 954–967. Bartkowska, K., Tepper, B., Turlejski, K., and Djavadian, R.L. (2018). Roles of
the exon junction complex components in the central nervous system: a mini
review. Rev. Neurosci. Published online May 23, 2018. https://doi.org/10. 1515/revneuro-2017-0113. Mishler, D.M., Christ, A.B., and Steitz, J.A. (2008). Flexibility in the site of exon
junction complex deposition revealed by functional group and RNA secondary
structure alterations in the splicing substrate. RNA 14, 2657–2670. Boehm, V., Britto-Borges, T., Steckelberg, A.-L., Singh, K.K., Gerbracht, J.V.,
Gueney, E., Blazquez, L., Altmueller, J., Dieterich, C., and Gehring, N.H. (2018). Exon junction complexes suppress spurious splice sites to safeguard tran-
scriptome integrity. Mol. Cell 72, this issue, 482–495. The authors declare no competing interests. The authors declare no competing interests. Jangi, M., and Sharp, P.A. (2014). Building robust transcriptomes with master
splicing factors. Cell 159, 487–498. Received: March 1, 2018 Received: March 1, 2018 Joseph, B., Kondo, S., and Lai, E.C. (2018). Short cryptic exons mediate recur-
sive splicing in Drosophila. Nat. Struct. Mol. Biol. 25, 365–371. Revised: August 24, 2018 Revised: August 24, 2018 Accepted: September 27, 2018 Kim, S.W., Taggart, A.J., Heintzelman, C., Cygan, K.J., Hull, C.G., Wang, J.,
Shrestha, B., and Fairbrother, W.G. (2017). Widespread intra-dependencies
in the removal of introns from human transcripts. Nucleic Acids Res. 45,
9503–9513. Published: November 1, 2018 Published: November 1, 2018 AUTHOR CONTRIBUTIONS Huppertz, I., Attig, J., D’Ambrogio, A., Easton, L.E., Sibley, C.R., Sugimoto, Y.,
Tajnik, M., Ko¨ nig, J., and Ule, J. (2014). iCLIP: protein-RNA interactions at
nucleotide resolution. Methods 65, 274–287. L.B. and J.U. conceived and designed the project. L.B., R.F., and J.M.B.P. performed the experiments. W.E., L.B., R.F., C.R.S., M.I., R.K.B., N.H., S.B.,
A.G., and J.M.B.P. analyzed the data. L.B. and J.U. wrote the manuscript,
with contributions from W.E. and R.F. Irimia, M., Weatheritt, R.J., Ellis, J.D., Parikshak, N.N., Gonatopoulos-
Pournatzis, T., Babor, M., Quesnel-Vallie`res, M., Tapial, J., Raj, B., O’Hanlon,
D., et al. (2014). A highly conserved program of neuronal microexons is misregu-
lated in autistic brains. Cell 159, 1511–1523. ACKNOWLEDGMENTS The authors thank Prof. Stephen Taylor for providing us with HeLa Flp-In
T-REx cell line, Prof. Gehring for sharing the eIF4A3 and MAGOH plasmids, Molecular Cell 72, 496–509, November 1, 2018
507 Molecular Cell 72, 496–509, November 1, 2018
507 reveals distinct roles for wnt signalling in the specification of spinal cord and
paraxial mesoderm identity. PLoS Biol. 12, e1001937. Dr. Birgit Aerne for her assistance with Drosophila cell lines, Flora Lee for opti-
mization of the iCLIP protocol and helpful feedback on the manuscript,
Dr. Mahmoud-Reza Rafiee for his assistance with mESC culture, The Francis
Crick Institute Cell Services and Genomics Equipment Park Science Technol-
ogy Platforms, and Dr. Martina Hallegger and all Ule lab members for construc-
tive discussions. This work was supported by the European Research Council
(617837-Translate), the Wellcome Trust (103760/Z/14/Z), Marie Curie Intraeur-
opean Fellowship (627783-NeuroCRYSP) to L.B, and the Francis Crick Insti-
tute, which receives its core funding from Cancer Research UK (FC001002),
the UK Medical Research Council (FC001002, MR/N013867/1), and the Well-
come Trust (FC001002). Haberman, N., Huppertz, I., Attig, J., Ko¨ nig, J., Wang, Z., Hauer, C., Hentze,
M.W., Kulozik, A.E., Le Hir, H., Curk, T., et al. (2017). Insights into the design
and interpretation of iCLIP experiments. Genome Biol. 18, 7. Hatton, A.R., Subramaniam, V., and Lopez, A.J. (1998). Generation of alterna-
tive Ultrabithorax isoforms and stepwise removal of a large intron by resplicing
at exon-exon junctions. Mol. Cell 2, 787–796. Hauer, C., Sieber, J., Schwarzl, T., Hollerer, I., Curk, T., Alleaume, A.-M.,
Hentze, M.W., and Kulozik, A.E. (2016). Exon junction complexes show a
distributional bias toward alternatively spliced mRNAs and against mRNAs
coding for ribosomal proteins. Cell Rep. 16, 1588–1603. REFERENCES Murachelli, A.G., Ebert, J., Basquin, C., Le Hir, H., and Conti, E. (2012). The
structure of the ASAP core complex reveals the existence of a Pinin-containing
PSAP complex. Nat. Struct. Mol. Biol. 19, 378–386. Duff, M.O., Olson, S., Wei, X., Garrett, S.C., Osman, A., Bolisetty, M., Plocik,
A., Celniker, S.E., and Graveley, B.R. (2015). Genome-wide identification of
zero nucleotide recursive splicing in Drosophila. Nature 521, 376–379. Pineda, J.M.B., and Bradley, R.K. (2018). Most human introns are recognized
via multiple and tissue-specific branchpoints. Genes Dev. 32, 577–591. Roignant, J.-Y., and Treisman, J.E. (2010). Exon junction complex subunits are
required to splice Drosophila MAP kinase, a large heterochromatic gene. Cell
143, 238–250. Faheem, M., Naseer, M.I., Rasool, M., Chaudhary, A.G., Kumosani, T.A., Ilyas,
A.M., Pushparaj, P., Ahmed, F., Algahtani, H.A., Al-Qahtani, M.H., and Saleh
Jamal, H. (2015). Molecular genetics of human primary microcephaly: an over-
view. BMC Med. Genomics 8 (Suppl 1), S4. Saulie` re, J., Murigneux, V., Wang, Z., Marquenet, E., Barbosa, I., Le Tonque` ze,
O., Audic, Y., Paillard, L., Roest Crollius, H., and Le Hir, H. (2012). CLIP-seq
of eIF4AIII reveals transcriptome-wide mapping of the human exon junction
complex. Nat. Struct. Mol. Biol. 19, 1124–1131. Freund, M., Asang, C., Kammler, S., Konermann, C., Krummheuer, J., Hipp,
M., Meyer, I., Gierling, W., Theiss, S., Preuss, T., et al. (2003). A novel approach
to describe a U1 snRNA binding site. Nucleic Acids Res. 31, 6963–6975. Shibuya, T., Tange, T.Ø., Stroupe, M.E., and Moore, M.J. (2006). Mutational
analysis of human eIF4AIII identifies regions necessary for exon junction com-
plex formation and nonsense-mediated mRNA decay. RNA 12, 360–374. Gehring, N.H., Lamprinaki, S., Hentze, M.W., and Kulozik, A.E. (2009). The
hierarchy of exon-junction complex assembly by the spliceosome explains
key features of mammalian nonsense-mediated mRNA decay. PLoS Biol. 7,
e1000120. Sibley, C.R., Emmett, W., Blazquez, L., Faro, A., Haberman, N., Briese, M.,
Trabzuni, D., Ryten, M., Weale, M.E., Hardy, J., et al. (2015). Recursive splicing
in long vertebrate genes. Nature 521, 371–375. Gouti, M., Tsakiridis, A., Wymeersch, F.J., Huang, Y., Kleinjung, J., Wilson, V.,
and Briscoe, J. (2014). In vitro generation of neuromesodermal progenitors 508
Molecular Cell 72, 496–509, November 1, 2018 Sibley, C.R., Blazquez, L., and Ule, J. (2016). Lessons from non-canonical
splicing. Nat. Rev. Genet. 17, 407–421. Valegaˆ rd, K., Murray, J.B., Stonehouse, N.J., van den Worm, S., Stockley,
P.G., and Liljas, L. (1997). Molecular Cell 72, 496–509, November 1, 2018
509 REFERENCES The three-dimensional structures of two complexes
between recombinant MS2 capsids and RNA operator fragments reveal
sequence-specific protein-RNA interactions. J. Mol. Biol. 270, 724–738. Singh, G., Kucukural, A., Cenik, C., Leszyk, J.D., Shaffer, S.A., Weng, Z., and
Moore, M.J. (2012). The cellular EJC interactome reveals higher-order mRNP
structure and an EJC-SR protein nexus. Cell 151, 750–764. Wang, Z., Murigneux, V., and Le Hir, H. (2014). Transcriptome-wide modula-
tion of splicing by the exon junction complex. Genome Biol. 15, 1–18. Stavridis, M.P., and Smith, A.G. (2003). Neural differentiation of mouse embry-
onic stem cells. Biochem. Soc. Trans. 31, 45–49. Yeo, G., and Burge, C.B. (2004). Maximum entropy modeling of short
sequence motifs with applications to RNA splicing signals. J. Comput. Biol. 11, 377–394. Taggart, A.J., Lin, C.-L., Shrestha, B., Heintzelman, C., Kim, S., and
Fairbrother, W.G. (2017). Large-scale analysis of branchpoint usage across
species and cell lines. Genome Res. 27, 639–649. Ying, Q.-L., Stavridis, M., Griffiths, D., Li, M., and Smith, A. (2003). Conversion
of Embryonic Stem Cells into Neuroectodermal Precursors in Adherent
Monoculture. Nat. Biotechnol. 21, 183–186. Teigelkamp, S., Newman, A.J., and Beggs, J.D. (1995). Extensive interac-
tions of PRP8 protein with the 50 and 30 splice sites during splicing suggest
a role in stabilization of exon alignment by U5 snRNA. EMBO J. 14, 2602–
2612. Zarnegar, B.J., Flynn, R.A., Shen, Y., Do, B.T., Chang, H.Y., and Khavari, P.A. (2016). irCLIP platform for efficient characterization of protein-RNA interac-
tions. Nat. Methods 13, 489–492. STAR+METHODS
KEY RESOURCES TABLE KEY RESOURCES TABLE
REAGENT or RESOURCE
SOURCE
IDENTIFIER
Antibodies
Rabbit anti-PRPF8 Antibody
Bethyl
Cat#A303-922A; RRID: AB_2620271
Rabbit anti-eIF4AIII Antibody
Abcam
Cat#ab32485; RRID: AB_732124
Mouse anti-RBM8A Antibody
SCBT
Cat#sc-32312; RRID: AB_2178827
Rabbit anti-MAGOH Antibody
Abcam
Cat#ab180505
Rabbit anti-UPF1 Antibody
Abcam
Cat#ab109363; RRID: AB_10861979
Mouse anti-FLAG Antibody
Sigma
Cat#F1804: RRID: AB_262044
Mouse anti-GFP Antibody
Santa Cruz
Cat#sc-9996; RRID: AB_627695
Rabbit anti-GAPDH Antibody
Cell signaling
Cat#2118L; RRID: AB_561053
Mouse anti-GAPDH Antibody
Abcam
Cat#ab8245; RRID: AB_2107448
Bacterial and Virus Strains
NEB 5-alpha Competent E. REFERENCES coli (High Efficiency)
New England Biolabs
Cat#C2987I
Biological Samples
Human Brain, Cerebellum Total RNA
Takara Bio
Cat#636535
Chemicals, Peptides, and Recombinant Proteins
TRIzol Reagent
Thermo Fisher Scientific
Cat#15596026
Phusion High-Fidelity DNA Polymerase (2 U/mL)
Thermo Fisher Scientific
Cat#F530L
10 mM dNTP Mix
Thermo Fisher Scientific
Cat#18427088
UltraPure Agarose
Thermo Fisher Scientific
Cat#16500500
BlueJuice Gel Loading Buffer
Thermo Fisher Scientific
Cat#10816015
Kanamycin Sulfate
Thermo Fisher Scientific
Cat#BP906-5
Zeocin Selection Reagent
Thermo Fisher Scientific
Cat#R25001
ESGRO Recombinant Mouse LIF Protein
Millipore
Cat#ESG1107
PD 0325901
Sigma
Cat#PZ0162-25MG
CHIR99021
Sigma
Cat#SML1046-25MG
Recombinant Mouse FGF basic Protein
R&D Systems
Cat#3139-FB-025
Lipofectamine RNAiMAX Transfection Reagent-1.5 mL
Thermo Fisher Scientific
Cat#13778150
Lipofectamine 2000 Transfection Reagent-1.5 mL
Thermo Fisher Scientific
Cat#11668019
Endoporter
GeneTools
http://www.gene-tools.com/endo_porter
AMPure XP, 5 mL
Agencourt
Cat#A63880
RIPA Buffer
Sigma-Aldrich
Cat#R0278-50ML
cOmplete(TM) Protease Inhibitor Cocktail
Sigma-Aldrich
Cat#11697498001
NuPAGE Novex 4-12% Bis-Tris Protein Gels,
1.0 mm, 10 well
Thermo Fisher Scientific
Cat#NP0321BOX
Lipofectamine 3000 Transfection Reagent-1.5 mL
Thermo Fisher Scientific
Cat#L3000015
Lenti-X Concentrator, 100 mL
Takara Clontech
Cat#631231
Puromycin
Takara Clontech
Cat#631305
Blasticidin S HCl
ThermoFisher Scientific
Cat#R21001
Hygromycin B (50mg/ml)
ThermoFisher Scientific
Cat#10687010
Doxycycline hyclate
Sigma-Aldrich
Cat#D9891
Novex TBE Gels, 6%, 10 well-1 box
Thermo Fisher Scientific
Cat#EC6265BOX
Critical Commercial Assays
DNA Clean & Concentrator-5
Zymo Research
Cat#D4014
Zymoclean Gel DNA Recovery
Zymo Research
Cat#D4007 e1
Molecular Cell 72, 496–509.e1–e9, November 1, 2018 Continued
REAGENT or RESOURCE
SOURCE
IDENTIFIER
SuperScript IV First-strand synthesis system
Thermo Fisher Scientific
Cat#18091050
Zero Blunt TOPO PCR Cloning Kit for Sequencing, with
One Shot TOP10 Chemically competent E.coli
Thermo Fisher Scientific
Cat#K2875J10
SENSE mRNA-Seq Library Prep Kit v2 for HiSeq, 96 preps
Lexogen
N/A
QIAxcel DNA Screening Kit (2400)
QIAGEN
Cat#929004
Fast SYBR Green Master Mix
Thermo Fisher Scientific
Cat#4385612
ImmoMix
BIOLINE
Cat#BIO-25020
Maxwell RSC simplyRNA Cells Kit
Promega
Cat#AS1390
High-Capacity cDNA Reverse Transcription
Kit-200 reactions
Thermo Fisher Scientific
Cat#4368814
MEGAclear Transcription Clean-Up Kit
Thermo Fisher Scientific
Cat#AM1908
MEGAscript T7 Transcription Kit
Thermo Fisher Scientific
Cat#AM1333
Deposited Data
Original gel and capillary electrophoresis images and
quantification for all figures
This study
https://doi.org/10.17632/7f9z9yxcx8.1
PRPF8 iCLIP after eIF4A3 knockdown in HeLa cells
This study
Raw data accessible via https://www. ebi.ac.uk/arrayexpress/ E-MTAB-
7269 and both raw and processed
data available at https://imaps. genialis.com
mRNA-seq after EJC component knockdown in S2 cells
This study
E-MTAB-7271. REFERENCES Accessible via https://
www.ebi.ac.uk/arrayexpress/
RNA-seq data from ENCODE
https://www.encodeproject.org/
search/?type=Experiment&assay_
title=shRNA+RNA-seq&limit=all
Table S7
RNA-seq data from K562 cells enriched for lariats
(Mercer et al., 2015)
GEO: GSE53328
RNA-seq data from K562 and NALM-6 cells enriched for
lariats
(Taggart et al., 2017)
SRA: SRP094107
RNA-seq data from HeLa cells after EJC KD
N/A
GEO: GSE63091
RNA-seq data after PNN KD in corneal epithelial cells
N/A
GEO: GSE73060
RNA-seq data after Acinus KD in HeLa cells
N/A
GEO: GSE81460
RNA-seq data after KD of NMD factors in HeLa cells
N/A
GEO: GSE86148
RNA-seq data after KD of EJC auxiliary factors in human
lymphoblastoid cell lines
N/A
GEO: GSE52834
RNA-seq data after KD of SR proteins in mouse P19 cells
N/A
GEO: GSE69733
RNA-seq data of EJC haploinsufficient mouse neocortices
N/A
GEO: GSE85576
eIF4A3 and BTZ iCLIP data
(Hauer et al., 2016)
ArrayExpress: E-MTAB-4215. RNA-seq HeLa control samples
NCBI sequence read archive
SRA: SRR514854
RNA-seq HeLa control samples
NCBI sequence read archive
SRA: SRR514855
Homo sapiens reference genome NCBI build 37, GRCh37
Genome Reference Consortium
https://www.ncbi.nlm.nih.gov/projects/
genome/assembly/grc/human/
Danio rerio reference genome (GRCz10 Build 88)
Genome Reference Consortium
N/A
Drosophila melanogaster reference genome (BDGP6
Build 88/ BDGP R5/dm3)
Berkeley Drosophila Genome
Project
http://www.fruitfly.org
Schizosaccharomyces pombe reference genome
(ASM294v2 Build 35)
Ensembl
https://fungi.ensembl.org/
Schizosaccharomyces_pombe/Info/Index
Ciona intestinalis reference genome (KH)
Ensembl
http://www.ensembl.org/Ciona_
intestinalis/Info/Index
(Continued on next page) Molecular Cell 72, 496–509.e1–e9, November 1, 2018
e2 Continued
REAGENT or RESOURCE
SOURCE
IDENTIFIER
Petromyzon marinus reference genome (7.0)
Ensembl
http://www.ensembl.org/Petromyzon_
marinus/Info/Index
Strongylocentrotus purpuratus reference genome (3.1)
Ensembl
https://metazoa.ensembl.org/
Strongylocentrotus_purpuratus/Info/
Annotation/
Experimental Models: Cell Lines
Human: K562 cells
ATCC
ATCC number CCL-243
Human: HeLa Flp-In T-Rex cells
N/A
Prof. EXPERIMENTAL MODEL AND SUBJECT DETAILS HeLa, HeLa Flp-In T-Rex, HEK293 and HEK293T cells (all of female origin) were cultured in Dulbecco’s modified Eagle medium. K562
cell (female origin) was cultured in Iscove’s Modified Dulbecco’s Medium. All cells were supplemented with 10% fetal bovine serum,
grown at 37C with 5% CO2 injection, and routinely passaged twice a week. HeLa Flp-In T-Rex cells were selected in the presence of
3ug ml-1 of blasticidin and 50ug ml-1 of Zeocin. Mouse ESCs (46C) cells (Ying et al., 2003) were grown feeder free on 0.2% gelatinized
cell culture plates in 2iL media (2i+LIF) (Stavridis and Smith, 2003). S2 cells were grown at room temperature in Drosophila
Schenider’s medium containing 10% fetal bovine serum. Cell lines were confirmed to be mycoplasma-free with repeated testing,
using the MycoAlert mycoplasma detection kit (Lonza). Cells were not authenticated by us, but retrieved from trusted sources as
listed in the Key Resources Table. CONTACT FOR REAGENT AND RESOURCE SHARING Further information and requests for resources and reagents should be directed to and will be fulfilled by the Lead Contact, Jernej Ule
(jernej.ule@crick.ac.uk). Further information and requests for resources and reagents should be directed to and will be fulfilled by the Lead Contact, Jernej Ule
(jernej.ule@crick.ac.uk). Further information and requests for resources and reagents should be directed to and will be fulfilled by the Lead Contact, Jernej Ule
(jernej.ule@crick.ac.uk). REFERENCES Stephen Taylor (University of
Manchester)
Human: HEK293T cells
European Collection of
Authenticated Cell
Cultures (ECACC)
12022001
Human: HEK293 cells
ATCC
ATCC number CRL-1573
Mouse: 46C cells
(Stavridis and Smith, 2003)
N/A
Drosophila: S2 cells
Drosphila Genomics Resource
Center (DGRC)
S2-DGRC
Oligonucleotides
Stealth RNAi siRNA Negative Control, Med GC
Thermo Fisher Scientific
Cat#12935300
KPNA1 Morpholino
GeneTools
50 GAATATCATCCCCTGTGACAATGTT 30
Control Morpholino
GeneTools
50 CCTCTTACCTCAGTTACAATTTATA 30
EIF4A3 Stealth siRNA
Thermo Fisher Scientific
Cat#HSS114709
UPF1 Stealth siRNA
Thermo Fisher Scientific
Cat#HSS109172
Recombinant DNA
QX DNA Size Marker 50–800 bp (50ul)
QIAGEN
Cat#929561
pcDNA 3.1(+) Mammalian Expression Vector
Thermo Fisher Scientific
Cat#V79020
pOG44 Flp-Recombinase Expression Vector
Thermo Fisher Scientific
Cat#V600520
pcDNA5 FRT/TO Vector Kit
Thermo Fisher Scientific
Cat#V652020
pLKO.1 puro
N/A
Addgene plasmid # 8453
pCMV-VSV-G
N/A
Addgene plasmid # 8454
pMDLg/pRRE
N/A
Addgene plasmid # 12251
pRSV-Rev
N/A
Addgene plasmid # 12253
pCI-neo FLAG eIF4A3
(Gehring et al., 2009)
N/A
pCI-neo FLAG MAGOH
(Gehring et al., 2009)
N/A
pCI-neo FLAG eIF4A3 E188R
(Gehring et al., 2009)
N/A
pCI-neo FLAG eIF4A3 401/402
(Gehring et al., 2009)
N/A
pCI-neo FLAG MAGOH E20R
(Gehring et al., 2009)
N/A
pCI-neo FLAG eIF4A3 E188Q
This study
Oligos for cloning detailed in Table S2
pMS2-GFP
This study
Oligos for cloning detailed in Table S2
pMS2-eIF4A3
(Gehring et al., 2009)
N/A
pMS2-eIF4AIII 401/402
(Gehring et al., 2009)
N/A
pcDNA3 and pcDNA5 splicing reporters
This study
Sequences detailed in Table S5
Software and Algorithms
Bowtie2
N/A
http://bowtie-bio.sourceforge.net/
bowtie2/index.shtml
R/Bioconductor
N/A
https://www.bioconductor.org/
R/dplyr
N/A
http://cran.r-project.org/web/
packages/dplyr/index htmld e3
Molecular Cell 72, 496–509.e1–e9, November 1, 2018 Continued
REAGENT or RESOURCE
SOURCE
IDENTIFIER
STAR RNA aligner
N/A
https://github.com/alexdobin/STAR
Samtools version 1.3.1
N/A
http://samtools.sourceforge.net/
Bedtools (v.2.17.0)
N/A
https://academic.oup.com/
bioinformatics/article-lookup/doi/
10.1093/bioinformatics/btq033
MAxEntScan
(Yeo and Burge, 2004)
http://genes.mit.edu/burgelab/maxent/
Xmaxentscan_scoreseq.html
MAJIQ: Modeling Alternative Junction Inclusion
Quantification
N/A
https://majiq.biociphers.org/
RSEM and EBSEQ
N/A
https://github.com/deweylab/RSEM
R
R Project for Statistical Computing
RRID: SCR_001905; http://www.r-
project.org/
RNAfold
N/A
http://rna.tbi.univie.ac.at/cgi-bin/
RNAWebSuite/RNAfold.cgi
iMaps webserver
N/A
https://imaps.genialis.com/
Hisat2 version 2.0.5
N/A
https://ccb.jhu.edu/software/hisat2/
index.shtml
Cutadapt
N/A
https://cutadapt.readthedocs.io/en/
stable/guide.html Plasmids (
)
y
g
(
)
siRNAs and Oligonucleotides. siRNA delivery was performed using Lipofectamine RNAiMax according to manufacturer’s recom-
mendations. Final concentration of siRNAs was 20nM. The sequences/reference numbers of siRNAs used are listed in Table S1 or
Key Resources Table. Cells were collected for analysis 48 hours after initial siRNA transfection. MAGOH KD was achieved by
combining siRNAs that target MAGOH and MAGOHB paralog genes. eIF4AIII, RBM8A, MAGOH and UPF1 KDs were done in
HeLa aCADM2 Flp-In to examine aCADM2 splicing pattern. eIF4AIII, PNN, RNPS1, SUPV3L1 and ASSC1 KDs were performed in
HeLa Flp-In T-REx host cell line. Morpholinos (GeneTools, USA) were delivered at 10uM final concentration using Endoporter reagent
in HeLa Flp-In T-REx KPNA1 Mut cell line or mouse NPCs. KPNA1 morpholino was reverse complement to nucleotides 9 to 34 in
the exon preceding the RS-exon, relative to the exon junction. The sequence was determined based on the local RNA structure (as
determined by RNAfold) as an accessible single-stranded region. Transient transfection. All transient transfections were carried out using Lipofectamine 2000 in HeLa or HEK293 cells grown
at z80% confluency in six-well plates. For unspliced and part-spliced splicing reporter experiments, 1ug of pcDNA3 KPNA1 or
aCADM2 unspliced, part-spliced or part-spliced mutant plasmids was transfected in HeLa Flp-In T-Rex host cell line and cells
were harvested 24 hours after transfection. For KD and rescue experiments, 20nM siRNAs and 1.5ug of pGFP or pCI-neo plasmids
were transfected in HeLa aCADM2 wild-type cell line. For tethering rescue experiments, 500ng of pcDNA5-SL2 splicing
reporters were co-transfected with a pGFP or pMS2 expression reporters in HEK293 cell lines. In both rescue experiments cells
were harvested 48 hours after transfection for RNA and protein isolation. dsRNA production and treatment. dsRNA production and treatment was done following the procedure previously described in
Aerne et al. (2015). Briefly, dsRNAs against mago and eIF4AIII mRNAs were synthesized by in vitro transcription using T7
MEGAscript and MEGAclear kits. PCR products used as templates for in vitro transcription were obtained by PCR using
Drosophila genomic DNA as template and the primers listed in Table S3. For knockdown, one million S2 cells were plated per
6 well in 2 m of serum containing medium. After 2-3h, 25ug of dsRNA were dissolved in 1ml of serum free medium, which was
added to the cells. Cells were soaked for 30 minutes, after that 2ml of additional serum containing medium was added. Plasmids pMS2-GFP plasmid was generated by PCR amplification of GFP ORF in pGFP plasmid and subsequent cloning into pMS2-
eIF4A3 using XhoI and NotI restriction sites to replace eIF4A3 with GFP. The oligonucleotides used for cloning are detailed Table S2. GCCGTGCCTC sequence. Wild-type SL2 sequences were obtained by gene synthesis in KPNA1 or cross-over PCR in mCADM2
splicing reporters respectively. To generate SL2 mutant reporters, C nucleotide in 20 position was mutated to a G, as this position
must be a pyrimidine for tight binding to MS2 coat protein (Valegaˆ rd et al., 1997). SL2 mutant plasmids were created by site-directed
mutagenesis using oligonucleotides detailed in Table S2. To move SL2 sequences further upstream the exon-exon junction,
sequences were obtained by gene synthesis and cloned into mCADM2 Unspl SL2 Wt splicing reporter using HindIII and AscI restric-
tion sites. Microexon containing KPNA1 Unspliced and Part-spliced wild-type and mutant sequences were obtained by gene syn-
thesis and cloned into pcDNA5/FRT/TO (pcDNA5) plasmid using HindIII-NotI restrictions sites. Sequences of all splicing reporters
are detailed in Table S5. Rescue plasmids: pCI-neo FLAG eIF4A3 E188Q construct was generated by site-directed mutagenesis. pMS2-GFP plasmid was generated by PCR amplification of GFP ORF in pGFP plasmid and subsequent cloning into pMS2-
eIF4A3 using XhoI and NotI restriction sites to replace eIF4A3 with GFP. The oligonucleotides used for cloning are detailed Table S2. Cell lines. To generate stable HeLa Flp-In T-Rex cell lines, splicing reporters cloned in pcDNA5 plasmids were transiently co-trans-
fected with pOG44 plasmid following manufacturer’s instructions. Positive selection of clones was done with 100-250 ug ml-1 of
hygromycin B. To induce expression of the stably integrated splicing reporter, media was supplemented with 200ng ml-1 of doxycy-
cline. pcDNA5 KPNA1 Unspliced Mut plasmid was used to generate KPNA1 RS-5ss Mutant cell line. pcDNA5 aCADM2 Unspliced Wt
and Mut plasmids were used to produce aCADM2 wild-type or RS-5ss mutant cell lines respectively. pcDNA5 PSMA3-AS1 Wt and
Mut plasmids were used to create PSMA3-AS1 wild-type and RS-5ss mutant cell lines respectively. Mouse ESCs (46C) were grown
feeder free on 0.2% gelatinized cell culture plates in 2iL media (2i+LIF) (Stavridis and Smith, 2003). To differentiate mESCs into neural
precursor cells (NPCs), single cells were plated at a density of 10,000 cells cm-2 in N2B27 media supplemented with 10ng ml-1 of
bFGF (R&D) for 3 days and then cultured in N2B27 media without growth factors (Gouti et al., 2014). Plasmids Splicing reporters. Main and alternative CADM2 (mCADM2/aCADM2) splicing reporters had been previously described (Sibley et al.,
2015). To generate KPNA1 splicing reporter, RS-exon and both upstream and downstream exons were cloned in HindIII-EcoRI sites
of pcDNA3 plasmid. Each exon was flanked by the nearest 100 nucleotides of their respective introns. Part-spliced constructs were
generated by removing the intronic sequence between the RS-exon and its preceding exon. Sequences were obtained by gene syn-
thesis (GeneArt, Life Technologies). If necessary, splicing reporters were sub-cloned from pcDNA3 to pcDNA5/FRT/TO (pcDNA5)
plasmid using HindIII-NotI restrictions sites. In PSMA3-AS1 splicing reporter, RS-exon and both upstream and downstream exons
flanked by 100 nucleotides of intronic sequence were cloned in pcDNA5 HindIII-NotI restriction sites by cross-over PCR using oli-
gonucleotides detailed in Table S2. To generate RPS2 splicing reporter, non RS-exon and both upstream and downstream exons
flanked by their respective introns were cloned in HindIII-NotI sites of pcDNA5 plasmid. Sequences were obtained by gene synthesis
(GeneArt, Life Technologies). All mutant splicing reporters with the sequences provided in Figure 3G were obtained by gene synthesis
(in KPNA1, aCADM2 and RPS2) or by site-directed mutagenesis using oligonucleotides detailed in Table S2 following Quick Change
Site-directed mutagenesis instructions (Agilent Technologies). To generate splicing reporters with Stem Loop 2 (SL2) sequence in the
upstream exon, nucleotides in positions 9 to 34 relative to the exon junction were replaced by AAAGCACGAGCATCA Molecular Cell 72, 496–509.e1–e9, November 1, 2018
e4 GCCGTGCCTC sequence. Wild-type SL2 sequences were obtained by gene synthesis in KPNA1 or cross-over PCR in mCADM2
splicing reporters respectively. To generate SL2 mutant reporters, C nucleotide in 20 position was mutated to a G, as this position
must be a pyrimidine for tight binding to MS2 coat protein (Valegaˆ rd et al., 1997). SL2 mutant plasmids were created by site-directed
mutagenesis using oligonucleotides detailed in Table S2. To move SL2 sequences further upstream the exon-exon junction,
sequences were obtained by gene synthesis and cloned into mCADM2 Unspl SL2 Wt splicing reporter using HindIII and AscI restric-
tion sites. Microexon containing KPNA1 Unspliced and Part-spliced wild-type and mutant sequences were obtained by gene syn-
thesis and cloned into pcDNA5/FRT/TO (pcDNA5) plasmid using HindIII-NotI restrictions sites. Sequences of all splicing reporters
are detailed in Table S5. Rescue plasmids: pCI-neo FLAG eIF4A3 E188Q construct was generated by site-directed mutagenesis. d ENCODE: 200 total junction reads per exon d ENCODE: 200 total junction reads per exon d Other public datasets (including GEO: GSE63091, GSE52834, GSE73060, GSE81460, GSE86148, GSE85576, GSE69733):
10 total junction reads per exon d Other public datasets (including GEO: GSE63091, GSE52834, GSE73060, GSE81460, GSE86148, GSE85576, GSE69733):
10 total junction reads per exon 10 total junction reads per exon Percent-spliced-in (PSI) was then calculated per sample as: Percent-spliced-in (PSI) was then calculated per sample as: PSI = 50 ðupstream + downstream junctionsÞ=ðskipping junction + 50 ðupstream + downstream junct PSI = 50 ðupstream + downstream junctionsÞ=ðskipping junction + 50 ðupstream + downstream junctionsÞÞ Change in exon inclusion (DPSI) for KD experiments was calculated based on difference between PSI in a specific KD and the mean
PSI of control samples. Customised data analysis pipelines were implemented using python (v.2.7.2), Bedtools (v.2.17.0) and R (v. 3.2.4).
D fii
th
i t
l Customised data analysis pipelines were implemented using python (v.2.7.2), Bedtools (v.2.17.0) and R Only exons internal to protein-coding genes were studied as defined by the presence of RNA-seq reads spanning both the upstream
and downstream junctions within each dataset (described below). Exon positions were determined by the following annotations:
GENCODE version 19 annotation (human genome build hg19), GENCODE version M11 (mouse genome build mm10) and ENSEMBL
version 86 (fruit fly genome build dm6). /5Phos/ WWW XXXXX NNNN AGATCGGAAGAGCGTCGTGAT /iSp18/ GGATCC /iSp18/ TACTGAACCG Purification of cDNAs following reverse transcription and circularization was performed using AMPure XP beads (Beckman-
Coulter, USA) and isopropanol. Libraries were sequenced as single end 100bp reads on Illumina HiSeq 4000. Immunoblot analysis. Cell pellets were lysed in RIPA buffer with protease inhibitors. 10-20mg of total protein extracts were resolved
in Novex Tris-Glycine 4%–12% gels, transferred to nitrocellulose membranes and blotted against eIF4AIII, RBM8A, MAGOH, UPF1,
FLAG or GFP proteins. GAPDH was used as a loading control. Category numbers for all antibodies are listed in Key Resources Table. Lentivirus production and infection shRNAs against Eif4a3 Rbm8a and Magoh genes were cloned into the AgeI/EcoRI sites of Immunoblot analysis. Cell pellets were lysed in RIPA buffer with protease inhibitors. 10-20mg of total protein extracts were resolved
in Novex Tris-Glycine 4%–12% gels, transferred to nitrocellulose membranes and blotted against eIF4AIII, RBM8A, MAGOH, UPF1,
FLAG or GFP proteins. GAPDH was used as a loading control. Category numbers for all antibodies are listed in Key Resources Table. Lentivirus production and infection. shRNAs against Eif4a3, Rbm8a and Magoh genes were cloned into the AgeI/EcoRI sites of
pLKO.1 puro plasmid using oligonucleotides detailed in Table S2. Each plasmid was co-transfected with pVSV-G, pRSV and
pRev plasmids in 293T cells using Lipofectamine 3000 following manufacturer’s instructions. 24 and 48 hours after transfection
cell media was collected and concentrated using Lenti-X Concentrator. Lentivirus particles were later used to infect neural precursor
cells and selected with 2mg ml-1 of Puromycin for 48 hours. Cells were harvested for RNA and protein analysis. FLAG or GFP proteins. GAPDH was used as a loading control. Category numbers for all antibodies are listed in Key Resources Table. Lentivirus production and infection. shRNAs against Eif4a3, Rbm8a and Magoh genes were cloned into the AgeI/EcoRI sites of
pLKO.1 puro plasmid using oligonucleotides detailed in Table S2. Each plasmid was co-transfected with pVSV-G, pRSV and
pRev plasmids in 293T cells using Lipofectamine 3000 following manufacturer’s instructions. 24 and 48 hours after transfection
cell media was collected and concentrated using Lenti-X Concentrator. Lentivirus particles were later used to infect neural precursor
cells and selected with 2mg ml-1 of Puromycin for 48 hours. Cells were harvested for RNA and protein analysis. mg
y
p
y
Direct lariat sequencing. Direct lariat sequencing for recursive lariat in AP1G2 gene was the same procedure described previously
in (Pineda and Bradley, 2018). The primers used are listed in Table S3. /5rApp/WN XXX AGA TCG GAA GAG CGG TTC AG/3Bio/ /5rApp/WN XXX AGA TCG GAA GAG CGG TTC AG/3Bio/ This allowed these replicates to be multiplexed prior to SDS-PAGE. The transfer of protein-RNA complexes was adapted for the
high molecular weight of PRPF8 by running an overnight transfer at 4C and at 15V with the addition of 0.05% SDS to the transfer
buffer. Reverse transcription was performed with barcoded primers containing UMIs: /5Phos/ WWW XXXXX NNNN AGATCGGAAGAGCGTCGTGAT /iSp18/ GGATCC /iSp18/ TACTGAACCGC Plasmids Cells
were lysed 3 days later and RNA-seq libraries were generated using SENSE mRNA-Seq Library Prep kit V2, following manufac-
turer’s instructions. RNA extraction and cDNA analysis. RNA was extracted from cell pellets using Maxwell RSC simply RNA cells kit in Maxwell RSC
instrument following manufacturer’s instructions. RNA was reverse transcribed using High-capacity cDNA synthesis kit using
random primers and standard protocol. A total of 1 mg was used in each reaction and cDNA then diluted 1:10. For RT-PCR, 2 mL
of diluted sample was used for each subsequent PCR reaction using 2X Immomix Master Mix and each primer at a final concentration
of 0.5mM. PCR products were visualized in a QIAxcel Advanced System using a QIAxcel DNA Screening kit (QIAGEN) following man-
ufacturer’s instructions. Splicing pattern of endogenous RS-exons was monitored using oligonucleotides detailed in Table S3. Splicing pattern of transiently or stably expressed splicing reporters was analyzed using a Forward oligo specific for the gene under
study and BGHpA Rv oligo. For qPCR, 5 mL of diluted sample was used for each reaction using SYBR green PCR mastermix and each
primer at a final concentration of 0.2mM in a QuantStudio 6 Flex Real-Time PCR System. Oligos used for qPCR are listed in Table S4. PRPF8 iCLIP iCLIP data for PRPF8 was derived from HeLa cells treated with either control or eIF4A3 siRNA as described above PRPF8 iCLIP. iCLIP data for PRPF8 was derived from HeLa cells treated with either control or eIF4A3 siRNA, as described above. Four replicate samples for each condition were generated. An antibody against endogenous PRPF8 was used. The iCLIP method
followed was described in Huppertz et al. (2014), with the following modifications. For the first replicate of each condition, e5
Molecular Cell 72, 496–509.e1–e9, November 1, 2018 protein-RNA complexes were visualized using a preadenylated, infrared dye labeled L3 adaptor (Zarnegar et al., 2016) with the
following sequence: protein-RNA complexes were visualized using a preadenylated, infrared dye labeled L3 adaptor (Zarnegar et al., 2016) with the
following sequence: /5Phos/ WWW XXXXX NNNN AGATCGGAAGAGCGTCGTGAT /iSp18/ GGATCC /iSp18/ TACTGAACCG Direct lariat sequencing. Direct lariat sequencing for recursive lariat in AP1G2 gene was the same proc
in (Pineda and Bradley, 2018). The primers used are listed in Table S3. /5rApp/AG ATC GGA AGA GCG GTT CAG AAA AAA AAA AAA /iAzideN/AA AAA AAA AAA A/3Bio/ /5rApp/AG ATC GGA AGA GCG GTT CAG AAA AAA AAA AAA /iAzideN/AA AAA AAA AAA A/3Bio/ For the following three replicates of each condition, an unlabelled L3 adaptor was ligated to the RNA wi Computational Analyses p
y
Customised data analysis pipelines were implemented using python (v.2.7.2), Bedtools (v.2.17.0) and R (v. 3.2.4). Defining the internal exons RNA-seq processing pipeline All raw sequence reads were aligned to human (hg19), mouse (mm10) or fruit fly (dm6) genomes respectively using STAR aligner v2.4
(https://github.com/alexdobin/STAR) with basic GENCODE annotations for canonical splice sites. Junction files were collected and
collated from samples within the same study. For each internal, protein-coding exon, the up- and downstream splice junctions
with highest read count were selected. The skip junction was then defined as the junction connecting the upstream exon to the
downstream exon based on these junctions. Filtering was done to remove exons with insufficient total junction read counts across
samples. Filtering criteria for each dataset is listed below: fðxiÞ = sumðxiÞ=ðsumðxiÞ + sumðxi + 1Þ. + sumðxnÞÞ where f is the normalization factor and x is the cDNA coverage. where f is the normalization factor and x is the cDNA coverage. cDNA coverage was then normalized by the normalization factor f(xi) for each exon group. cDNA coverage was then normalized by the normalization factor f(xi) for each exon group. Processing of the PRPF8 iCLIP data was performed using the iMaps webserver (https://imaps.genialis.com/). The data was map-
ped to the GRCh38/GENCODE v27 genome assembly using STAR (version 2.6.0) with default settings. PCR duplicates and reads
that did not map uniquely to the genome were discarded. Reads for each replicate were separated based on the presence or absence
of a junction within the read. For junction-containing reads, only reads that start and end in an annotated exon were considered. Junc-
tion-containing reads were then classified to RS or non-RS groups on the basis of the read ending in an RS or non-RS exon, respec-
tively. For each read, the distance from the read start to the end of the exon was calculated. The frequency of read start-distance for
each group was plotted as a frequency polygon using R (version 3.5.0) and and the ggplot2 package. The LOESS algorithm was used
to smooth the data with span set to 0.2. The data was normalized on the basis of the total number of reads for each sample’s library
and the total number of exons in the exon class surveyed for that group (e.g., RS versus non-RS). Reads ending in exons that con-
tained only a single read across all samples were excluded from the analysis. EJC-sensitive exons were defined as those that showed
a greater than 0.05 dPSI between eIF4A3 knockdown and control in the ENCODE RNaseq data. Junction-absent reads were clas-
sified in to RS or non-RS groups on the basis of the RS status of the downstream exon. Frequency plots were then calculated using
the same method as for the junction-containing reads. p
Defining non RS and RS exon categories All exons with RS-5ss > threshold at the exon-exon junction were then considered as potentially recursive
‘‘RS exons,’’ while the remaining exons were considered ‘‘nonRS exons.’’ For each experiment, DPSI values for each exon category (alternative (15% < PSI < 85%), highly-included alternative (85% < PSI <
98%) and constitutive exons (PSI > 98%) were calculated by comparing two groups of exons, one above and one blow a threshold
defined by the RS-5ss score. The RS-5ss score threshold produced two groups of exons which could be tested for skew in DPSI
values using the Wilcox rank sum test. A range of RS-5ss score threshold values was then examined, from 20 to 8, in order to deter-
mine how the DPSI values were affected by the threshold. The signed P value (based on the sign of the test statistic and the generated
P value) for each RS-5ss score threshold are shown in Figures 1G, 2A, and 2B. For all RNA-seq samples showing significant signed P
value for exons with RS-5ss > 4 (indicating that their inclusion decreased compared to other exons), the data were reanalysed using
MAJIQ to recalculate PSI. DPSI estimates for all further analyses were calculated as the difference between the control sample PSI
value and the knockdown sample PSI value. Evolutionary comparison of 50 splice sites In order to estimate the prevalence of potential RS-exons across evolution, we developed a simple splice site scoring algorithm that
took into account the characteristics of 50 splice sites (5ss) present in each species. A collection of top 1000 most prevalent 9mers
were collected from canonical 5ss. The presence of these the 1000 canonical 5ss 9mers was then examined at each potential RS-5ss
by using ENSEMBL exon annotations for the following species; Schizosaccharomyces pombe (ASM294v2 Build 35), Danio rerio
(GRCz10 Build 88), Drosophila melanogaster (BDGP6 Build 88), Homo sapiens (GRCh37.p13 Build 88). iCLIP data analysis and visualization p
Defining non RS and RS exon categories MaxEnt splice site scoring software was used to determine the score of 50 splice sites (5ss) (Yeo and Burge, 2004). To determine the
threshold for RS-5ss to identify candidate RS-exons, we first determined for each species the MaxEntScan score present at 90% of
canonical 5ss for these species. For this analysis, we used all exon-intron junctions of annotated exons for the species where the
MaxEntScan score of 5ss was > 0. This was done because the distribution of MaxEntScan scores across exon-intron junction
was bimodal, with the major peak of 5ss was found between 0 and 12 (Figure 7A). We suspect that the minor peak of 50ss with scores
between 30 and 0 are more likely to be spurious sites that result from false annotation, or non-canonical splice sites that are present
at a low proportion at true exons (Sibley et al., 2016). For human transcriptome, the threshold was 5.52, For each exon, the potential Molecular Cell 72, 496–509.e1–e9, November 1, 2018
e6 Molecular Cell 72, 496–509.e1–e9, November 1, 2018
e6 reconstituted 50 splice site (hereafter: RS-5ss) was then examined in the same way after linking each exon to the preceding exon. For
analysis of human exons, the end of the preceding exon was defined by RNA-seq, such that the upstream splice junction with most
reads for that exon was used. For other species, only the annotated position of the nearest preceding exon was used, as defined by
ENSEMBL annotations for the following species: Schizosaccharomyces pombe (ASM294v2), Danio rerio (GRCz10), Drosophila
melanogaster (BDGP6), Homo sapiens (GRCh37.75), Ciona intestinalis (KH), Petromyzon marinus (Pmarinus_7.0) and Strongylocen-
trotus purpuratus (3.1). All exons with RS-5ss > threshold at the exon-exon junction were then considered as potentially recursive
‘‘RS exons,’’ while the remaining exons were considered ‘‘nonRS exons.’’ reconstituted 50 splice site (hereafter: RS-5ss) was then examined in the same way after linking each exon to the preceding exon. For
analysis of human exons, the end of the preceding exon was defined by RNA-seq, such that the upstream splice junction with most
reads for that exon was used. For other species, only the annotated position of the nearest preceding exon was used, as defined by
ENSEMBL annotations for the following species: Schizosaccharomyces pombe (ASM294v2), Danio rerio (GRCz10), Drosophila
melanogaster (BDGP6), Homo sapiens (GRCh37.75), Ciona intestinalis (KH), Petromyzon marinus (Pmarinus_7.0) and Strongylocen-
trotus purpuratus (3.1). Differential gene expression of SUPV3L1 RSEM transcript estimate data was downloaded from https://www.encodeproject.org/ for both SUPV3L1 (K562 cell line:
ENCBS534VZR) and its Control (K562 cell line: ENCSR778SIU). EBSEQ was run using default settings to produce differential
gene expression statistics. iCLIP data analysis and visualization Mapping of the eIF4A3 and BTZ iCLIP data (Hauer et al., 2016) to the UCSC hg19/GRCh37 genome assembly was performed using
STAR (version 020201) alignment software with default settings. cDNAs with the same unique molecular identifier (UMI) that mapped
to the same genomic position were considered as PCR duplicates and collapsed to a single cDNA. All normalizations were performed
in R (version 3.1.0) together with the ‘‘ggplot2’’ and the ‘‘smoother’’ packages for visualizing the results. To visualize the normalized
cDNA coverage of eIF4A3 and BTZ iCLIP data (Hauer et al., 2016), we used the full sequence of cDNAs, since these cDNAs represent
crosslink sites at their starts, but also inform on RNase protection by EJC over their whole sequence (Haberman et al., 2017). Each density graph shows normalized cDNA coverage around the 5ss upstream to EJC-sensitive and insensitive RS-exons. For
each group of exons, we measured the cDNA coverage from RNA-seq data and calculated the normalization factor f(xi) in the
following way: fðxiÞ = sumðxiÞ=ðsumðxiÞ + sumðxi + 1Þ. + sumðxnÞÞ QUANTIFICATION AND STATISTICAL ANALYSIS All experiments were done at a minimum of three independent replicates, unless specified. Data in quantifications shown in Supple-
mental Figures are expressed as mean ± standard deviation (SD). Statistical analysis was performed with Student’s t-Test using
R version 3.3.1. Significant differences (P < 0.05) are indicated with a star (*). To test for differences in DPSI between groups of exons with similar RS-5ss score in each experiment, DPSI values for each exon
category (alternative (15% < PSI < 85%), highly-included alternative (85% < PSI < 98%) and constitutive exons (PSI > 98%) were
calculated by comparing two groups of exons, one above and one blow a threshold defined by the RS-5ss score. The RS-5ss score
threshold produced two groups of exons which could be tested for skew in DPSI values using the Wilcox rank sum test. A range of
RS-5ss score threshold values was then examined, from 20 to 8, in order to determine how the DPSI values were affected by the
threshold. The signed P value (based on the sign of the test statistic and the generated P value) for each RS-5ss score threshold are
shown in Figures 1G, 2A, and 2B. Branchpoint inference Lariats arising from RS-exon-dependent splicing were computationally inferred as previously described (Pineda and Bradley, 2018)
from RNA-seq data obtained from Mercer et al. (2015) and Taggart et al. (2017) with the following modification: rather than using all
possible pairings between annotated 5ss and 3ss as input to the branchpoint inference procedure, all possible pairings between the
50ends of exons and 3ss were used. ,
eIF4A3 sensitive microexon identification Exon-exon junctions were created for all exons sensitive to KDs of EJC components using the coordinates of the canonical, upstream
and downstream exons (A, C1 and C2, respectively). For each exon A of at least 21 nucleotides, we identified potential 50 splice sites
with MaxEntScan scores of at least 5.52 ranging from 0 to 15 nucleotides from the C1A junction. This created a library of four types of
sequences per sensitive exon: C1-C2, C1-A, A-C2 and exon skipping events leading to full skipping of RS-exons or 1-15nt long
RS-linked microexons. The scores of potential 50 splice sites were calculated employing the Maximum Entropy (MaxEnt) metrics
(Yeo and Burge, 2004). Reads from RNA-seq data from eIF4A3 KD in HeLa cells (Wang et al., 2014) were trimmed to 50 nucleotides
using sliding windows of 25 nucleotides and aligned to the human hg19 genome using bowtie v1.1.2 with -m 1 -v 2 options. Reads
that did not map to the genome were then mapped to the library of junctions using bowtie v1.1.2 with the following parameters: -f -a -v
2. We corrected read counts by the number of potentially mappable position in the sequence for 50-nucleotides reads and requiring
a minimum of 8-nucleotides being mapped at each side of the junction. Only those events with at least 10 reads support
were considered. We defined a metric, Percent Usage of RS-5SS (PURS), to estimate the use of the RS-5ss, with respect to the
‘‘canonical’’ one using corrected read counts: PURS =
RS n100
ðC1 E + E C2Þ=2 The difference between the PURS in the eIF4A3 KD and control was expressed as delta PURS (DPURS). To identify competing
50 splice sites upon eIF4A3 KD, we selected RS-exons or RS-linked microexons with MaxEnt score of at least 5.52 and dPURS of
at least 10. Detection of intron splicing-order 750,490,820 reads from two RNA-seq HeLa control samples (paired end, 51 nt, run IDs SRR514854 and SRR514855) were down-
loaded from the NCBI sequence read archive. These reads are assumed to be enriched in reads from partially spliced transcripts
because they come from the rRNA-depleted, not polyA-selected nuclear RNA fraction. After the removal of the Illumina 30 sequencing e7
Molecular Cell 72, 496–509.e1–e9, November 1, 2018 adaptor (AGATCGGAAGAGCACACGTCTGAACTCCAGTCA) with Cutadapt, the reads were mapped to the human genome assem-
bly Hg19 with the splice mapper Hisat2 version 2.0.5. To enhance mapping of spliced reads, Hisat2 was supplied with two sources of
splicing information. First, with the Hg19 Ensembl genome annotation (GRCh37.p13). Second, with specifically extracted splice junc-
tions for all EJC-sensitive exons corresponding to the most common upstream and downstream introns. Last, evidence counts for
the upstream or downstream intron spliced first were extracted from all mapped read pairs with a custom program and Samtools
version 1.3.1. A read pair mapping to the upstream/downstream splice junction of an exon and to the downstream/upstream intron
did account for one evidence count for the upstream/downstream intron spliced first. Only those exons where the sum of the two
evidence counts for upstream/downstream intron spliced first was at least 10 were included in this analysis. Exons are binned in
RS and nonRS categories if their RS-5ss score is above or below 5.52 respectively. EC-sensitive exons were defined as having a
dPSI < 0.1 in HeLa cells after eIF4A3 KD, whereas EJC-insensitive exons were defined as having absolute dPSI values < 0.02. eIF4A3 sensitive microexon identification adaptor (AGATCGGAAGAGCACACGTCTGAACTCCAGTCA) with Cutadapt, the reads were mapped to the human genome assem-
bly Hg19 with the splice mapper Hisat2 version 2.0.5. To enhance mapping of spliced reads, Hisat2 was supplied with two sources of
splicing information. First, with the Hg19 Ensembl genome annotation (GRCh37.p13). Second, with specifically extracted splice junc-
tions for all EJC-sensitive exons corresponding to the most common upstream and downstream introns. Last, evidence counts for
the upstream or downstream intron spliced first were extracted from all mapped read pairs with a custom program and Samtools
version 1.3.1. A read pair mapping to the upstream/downstream splice junction of an exon and to the downstream/upstream intron
did account for one evidence count for the upstream/downstream intron spliced first. Detection of intron splicing-order Only those exons where the sum of the two
evidence counts for upstream/downstream intron spliced first was at least 10 were included in this analysis. Exons are binned in
RS and nonRS categories if their RS-5ss score is above or below 5.52 respectively. EC-sensitive exons were defined as having a
dPSI < 0.1 in HeLa cells after eIF4A3 KD, whereas EJC-insensitive exons were defined as having absolute dPSI values < 0.02. eIF4A3 sensitive microexon identification DATA AND SOFTWARE AVAILABILITY The accession number for the iCLIP sequencing data files for PRPF8 iCLIP upon eIF4A3 KD reported in this paper is ArrayExpress:
E-MTAB-7269, and for mRNAseq data of Drosophila melanogaster S2 cells after EJC component KD is ArrayExpress: E-MTAB-7271. Raw and processed iCLIP data are available also at https://imaps.genialis.com. The mRNaseq data of Drosophila melanogaster S2
cells after EJC component knockdown under E-MTAB-7271. Original gel and capillary electrophoresis images and quantification for
all figures are available at https://doi.org/10.17632/7f9z9yxcx8.1. Molecular Cell 72, 496–509.e1–e9, November 1, 2018
e8 e9
Molecular Cell 72, 496–509.e1–e9, November 1, 2018 Public RNA-seq data
ENCODE RNA-seq data for all 191 K562 cell line shRNA KD samples were downloaded from https://www.encodeproject.org
(See experiments accession numbers in Table S7) and processed using the RNA-seq analysis pipeline outlined below. Other public
RNA-seq data with the following accession numbers were downloaded from the short read archive https://www.ncbi.nlm.nih.gov/
sra/ and processed using the RNA-seq analysis pipeline.
- Studies that included KD of at least one previously reported EJC-associated factor to identify factors that contribute to inclusion
of RS-exons: Human: GEO: GSE63091, GSE52834, GSE73060, GSE81460, GSE86148 and mouse: GSE69733.
- RNaseq data from Magoh haploinsufficient mouse brain (MagohMos2/+) to analyze the effect of lower levels of EJC in the brain:
GEO: GSE85576. Public RNA-seq data Public RNA-seq data
ENCODE RNA-seq data for all 191 K562 cell line shRNA KD samples were downloaded from https://www.encodeproject.org
(See experiments accession numbers in Table S7) and processed using the RNA-seq analysis pipeline outlined below. Other public
RNA-seq data with the following accession numbers were downloaded from the short read archive https://www.ncbi.nlm.nih.gov/
sra/ and processed using the RNA-seq analysis pipeline. - Studies that included KD of at least one previously reported EJC-associated factor to identify factors that contribute to inclusion
of RS-exons: Human: GEO: GSE63091, GSE52834, GSE73060, GSE81460, GSE86148 and mouse: GSE69733. - RNaseq data from Magoh haploinsufficient mouse brain (MagohMos2/+) to analyze the effect of lower levels of EJC in the brain:
GEO: GSE85576. - Studies that included KD of at least one previously reported EJC-associated factor to identify factors that contribute to inclusion
of RS-exons: Human: GEO: GSE63091, GSE52834, GSE73060, GSE81460, GSE86148 and mouse: GSE69733. - RNaseq data from Magoh haploinsufficient mouse brain (MagohMos2/+) to analyze the effect of lower levels of EJC in the brain: ,
,
,
,
- RNaseq data from Magoh haploinsufficient mouse brain (MagohMos2/+) to analyze the effect of lower levels of EJC in the brain:
GEO: GSE85576.
|
https://openalex.org/W2103060999
|
https://europepmc.org/articles/pmc3563487?pdf=render
|
English
| null |
Methicillin-resistant Staphylococcus aureus containing mecC in Swedish dairy cows
|
Acta veterinaria Scandinavica
| 2,013
|
cc-by
| 2,454
|
Unnerstad et al. Acta Veterinaria Scandinavica 2013, 55:6
http://www.actavetscand.com/content/55/1/6 Open Access Abstract Background: Hitherto, methicillin-resistant Staphylococcus aureus (MRSA) has not been detected in Swedish cattle. However, due to the report of mecC, a novel homologue to the mecA gene, there was reason to re-evaluate
susceptibility results from strain collections of Staphylococcus aureus and test suspected isolates for the presence of
mecC. Findings: Bovine isolates of S. aureus with elevated minimum inhibitory concentrations of beta-lactams were
retrospectively tested for presence of mecC. In four of the isolates mecC was detected. Conclusion: In Sweden, this is the first finding of MRSA in cattle and the first detection of MRSA harbouring mecC
of domestic animal origin. MRSA in animal populations has implications as a potential reservoir with risk for spread
to humans. Occurrence of MRSA among Swedish cattle appears still very limited. Keywords: MRSA, Staphylococcus aureus, mecC, Mastitis, Dairy cows clinical samples in the UK, Denmark and Ireland [6,7]. The mecC has only ~70% similarity with mecA and is not
identified with conventional confirmatory methods [6]. © 2013 Unnerstad et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the
Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited. * Correspondence: helle.unnerstad@sva.se
Department of Animal Health and Antimicrobial Strategies, National
Veterinary Institute, Uppsala SE-751 89, Sweden Methicillin-resistant Staphylococcus aureus
containing mecC in Swedish dairy cows Helle Ericsson Unnerstad*, Björn Bengtsson, Margareta Horn af Rantzien and Stefan Börjesson Unnerstad et al. Acta Veterinaria Scandinavica 2013, 55:6
http://www.actavetscand.com/content/55/1/6 Page 2 of 3 207 submissions (2%), penicillinase-producing S. aureus
was detected in the routine testing using the “clover-
leaf” method [10]. The samples emanated from dairy farms
in different parts of Sweden but the MRSA-screening was
performed anonymously and epidemiological information
of individual samples, such as geographical origin, was not
known. Samples most likely originated from cows with
mastitis although clinical data on each cow were not avail-
able. During January to April 2010, all penicillinase-
producing isolates were tested for resistance to oxacillin
and cefoxitin by microdilution using the VetMIC MRS
panel (National Veterinary Institute, Uppsala, Sweden) fol-
lowing CLSI standard M31-A3 [11], but during the
remaining period only one isolate per submission was
tested. In total, this resulted in 311 penicillinase-producing
isolates analysed by microdilution and seven of these were
suspected of being MRSA due to elevated minimum inhibi-
tory concentrations (MICs) of oxacillin and cefoxitin, but
the mecA gene was not detected with polymerase chain re-
action (PCR). When knowledge about the novel mecA
homologue became available, our results were re-evaluated
and all isolates with MICs of oxacillin (with 2% NaCl) and /
or cefoxitin ≥4 mg/L (in total 58 isolates), were tested for
the presence of mecA and mecC with PCR [6]. Four of
these isolates were verified as MRSA carrying mecC. been tested for antimicrobial susceptibility as described
above. Results of susceptibility testing of 419 isolates of
S. aureus from dairy cows since 2001 were available for
re-evaluation. In this material, 39 isolates were subjected
to testing for the presence of mecA and mecC with PCR,
but MRSA was not detected. In total, 730 (311 + 419) isolates were available for in-
vestigation, but only four were confirmed to be MRSA
indicating a low prevalence among dairy cows in Swe-
den, at least in association with mastitis. MRSA with
mecC has also been identified in human clinical samples
in Sweden [16]. Since the geographic origin of the bo-
vine isolates is unknown it is not possible to investigate
epidemiological links between isolates or links to human
isolates of MRSA from Swedish healthcare. The Swedish
bovine isolates belonged to the same MLST:s identified
in bovine milk samples in the UK and in human samples
from the UK, Denmark, Ireland and Germany [6,7,17]. However, none of the Swedish bovine isolates was of
spa-type
t843
(04-82-17-25-17-25-25-16-17),
which
appears to be common in other countries [6,17,18]. Acknowledgments This work was partly supported by the Swedish Board of Agriculture. Dr Mark A Holmes, Department of Veterinary Medicine, University of
Cambridge, UK, is kindly acknowledged for providing a mecC positive control
strain. Authors’ contributions
d
h d HEU participated in the design of the study and drafted the manuscript. BB
participated in the design of the study and helped to draft the manuscript. MHR participated in the design of the study and carried out the
susceptibility testing. SB participated in the design of the study, helped to
draft the manuscript and carried out the molecular analyses. All authors read
and approved the final manuscript. Competing interests
The authors declare that they have no competing interests. Competing interests
The authors declare that they have no competing interests. Unnerstad et al. Acta Veterinaria Scandinavica 2013, 55:6
http://www.actavetscand.com/content/55/1/6 It
has been suggested that MRSA CC130 might be bovine
associated, but further studies are needed to establish if
this truly is the case [6]. In conclusion, this is the first finding of MRSA in Swed-
ish cattle, as well as the first detection of MRSA with
mecC of domestic animal origin in Sweden. In addition,
occurrence of MRSA among Swedish cattle appears still
very limited. The confirmed MRSA isolates were further character-
ized by spa-typing [12], multilocus sequence typing
(MLST) [13], pulsed-field gel electrophoresis (PFGE)
[14] and detection of the Panton Valentine leukocidine
(PVL) toxin genes [15]. They were also tested for anti-
microbial susceptibility to cephalothin, chloramphenicol,
ciprofloxacin, clindamycin, erythromycin, fucidic acid,
gentamicin, kanamycin, oxacillin, penicillin, tetracycline
and trimethoprim by microdilution using the VetMIC
GP-mo panel (National Veterinary Institute, Uppsala,
Sweden) following CLSI standard M31-A3 [11] Three
of the isolates, originating from milk samples collected
in 2010, were of spa-type t524 (spa repeat succession
04–17) and ST130 (CC130) and had identical PFGE-pat-
terns. One isolate, originating from a milk sample col-
lected in 2011, was of spa-type t9111 (14-44-12-23-18-17-
17-17-23-24), ST425 (CC425) and showed a PFGE-pattern
different from the other three isolates. The PVL-genes
were not detected in any of the isolates. All four isolates
were resistant to beta-lactams, but susceptible to all other
antimicrobials tested. The isolates were confirmed to pro-
duce penicillinase which is noteworthy because, to our
knowledge, penicillinase production has not been reported
in isolates with mecC despite presence of the beta-
lactamase gene blaZ [6]. Findings Methicillin-resistant Staphylococcus aureus (MRSA) first
emerged as a problem in hospitals but is now also widely
distributed in the community, although the prevalence
varies among European countries [1]. In animal settings,
MRSA has been an increasing problem for the last ten
years, initially as the cause of clinical disease in compan-
ion animals and horses. It is now widely distributed in
pig
populations
in
many
countries
and
has
also
been described in poultry and veal calves [2]. In most
food-producing animals, MRSA rarely causes clinical
disease, although there are reports of arthritis, dermatitis
and sepsis in pigs [3]. In dairy cows, S. aureus is a com-
mon bacterial cause of mastitis and MRSA is known to
cause
mastitis
as
well
[4]. Among
food-producing
animals, the MRSA lineage clonal complex (CC) 398 is
clearly
dominating. A
reservoir
in
food-producing
animals may constitute a risk for human health and can
give a significant contribution to the burden of MRSA in
human healthcare, at least in low prevalence countries
[5]. In 2011 MRSA with a divergent mecA homologue,
named mecC (formerly mecALGA251), was detected in
milk samples from dairy cows in the UK and human Sweden is still a country with low prevalence of MRSA
infections in humans and < 1% of invasive S. aureus
isolates are MRSA [8]. Therefore, measures to prevent a
situation where animals become a reservoir for MRSA are
important. The situation in production animals in Sweden
is still favourable and so far MRSA has only been detected
in one pig herd, indicating a low prevalence also in the pig
population [9]. In order to investigate the presence of MRSA in dairy
cows in Sweden, penicillinase-producing S. aureus iso-
lates originating from milk samples sent to the Mastitis
Laboratory,
National
Veterinary
Institute,
Uppsala,
Sweden for routine bacteriology were screened for
MRSA phenotype in 2010–2011. For practical reasons
penicillinase-negative isolates were not tested, since it
was expected that the majority of MRSA-isolates pro-
duce penicillinase. During the time period, 8757 submissions of milk
samples from cows were received. Each submission con-
stituted a variable number of milk samples from one
farm, and samples from the same farm could have been
submitted more than once. In 534 (6%) of the submis-
sions, at least one sample contained S. aureus and in Unnerstad et al. Acta Veterinaria Scandinavica 2013, 55:6
http://www.actavetscand.com/content/55/1/6 Unnerstad et al. Acta Veterinaria Scandinavica 2013, 55:6
http://www.actavetscand.com/content/55/1/6 clinical and subclinical mastitis in Belgian cows. Vet Microbiol 2010,
144:166–171. 5. European Food Safety Authority: Scientific opinion of the panel on
biological hazards on a request from the European Commission on
assessment of the public health significance of meticillin resistant
Staphylococcus aureus (MRSA) in animals and foods. The EFSA Journal. 2009, 993:1–73. 6. Garcia-Alvarez L, Holden TG, Lindsay H, Webb CR, Brown DFJ, Curran MD,
Walpole E, Brooks K, Pickard DJ, Teale C, Parkhill J, Bentley SD, Edwards GF,
Girvan EK, Kaerns AM, Pichon B, Hill RLR, Larsen AR, Skov RL, Peacock SJ,
Maskell DJ, Holmes MA: Meticillin-resistant Staphylococcus aureus with a
novel mecA homologue in human and bovine populations in the UK
and Denmark: a descriptive study. Lancet Infect Dis 2011, 11:595–603. 6. Garcia-Alvarez L, Holden TG, Lindsay H, Webb CR, Brown DFJ, Curran MD,
Walpole E, Brooks K, Pickard DJ, Teale C, Parkhill J, Bentley SD, Edwards GF,
Girvan EK, Kaerns AM, Pichon B, Hill RLR, Larsen AR, Skov RL, Peacock SJ,
Maskell DJ, Holmes MA: Meticillin-resistant Staphylococcus aureus with a
novel mecA homologue in human and bovine populations in the UK
and Denmark: a descriptive study. Lancet Infect Dis 2011, 11:595–603. 7. Shore AC, Deasy EC, Slickers P, Brennan G, O’Connell B, Monecke S, Ehricht
R, Coleman DC: Detection of staphylococcal cassette chromosome mec
type XI carrying highly divergent mecA, mecI, mecR1, blaZ, and ccr genes
in human clinical isolates of clonal complex 130 methicillin-resistant
Staphylococcus aureus. Antimicrob Agents Chemother 2011, 55:3765–3773. 8. European Center for Disease Prevention and Control: Antimicrobial resistance
surveillance in Europe 2010. Sweden: ECDC, Stockholm; 2011. http://www. ecdc.europa.eu/en/publications/Publications/1111_SUR_AMR_data.pdf.pdf. 9. Ericsson Unnerstad H, Lindberg M, Börjesson S, Grönlund Andersson U:
Screening for methicillin-resistant Staphylococcus aureus (MRSA) in pigs
and horses in Sweden [abstract]. In Proceedings of the 2nd ASM-ESCMID
Conference on Methicillin-resistant Staphylococci in Animals: Veterinary and
Public Health Implications: 8–11 September, 2011. Washington, DC; 2011:47. 10. Bryan LE, Godfrey AJ: Beta-lactam antibiotics: mode of action and
bacterial resistance. In Antibiotics in laboratory medicine. Edited by
Baltimore LV. USA: Williams & Wilkins; 1991:648. 11. Clinical and Laboratory Standards Institute: Performance standards for
antimicrobial disk and dilution susceptibility tests for bacteria isolated from
animals; approved standard. 3rd edition. Wayne, PA: M31-A3. CLSI; 2008. 12. Unnerstad et al. Acta Veterinaria Scandinavica 2013, 55:6
http://www.actavetscand.com/content/55/1/6 Harmsen D, Claus H, Witte W, Rothganger J, Turnwald D, Vogel U: Typing of
methicillin-resistant Staphylococcus aureus in a university hospital setting
by using novel software for spa repeat determination and database
management. J Clin Microbiol 2003, 41:5442–5448. 13. Enright MC, Day NP, Davies CE, Peacock SJ, Spratt BG: Multilocus sequence
typing for characterization of methicillin-resistant and methicillin-
susceptible clones of Staphylococcus aureus. J Clin Microbiol 2000,
38:1008–1015. 14. Murchan SM, Kaufmann E, Deplano A, De Ryck R, Struelens M, Zinn CE,
Fussing V, Salmenlinna S, Vuopio-Varkila J, El Solh N, Cuny C, Witte W,
Tassios PT, Legakis N, Leeuwen W, Van Belkum A, Vindel A, Laconcha I,
Garaizar J, Haeggman S, Olsson-Liljequist B, Ransjo U, Coombes G, Cookson
B: Harmonization of pulsed-field gel electrophoresis protocols for
epidemiological typing of strains of methicillin-resistant Staphylococcus
aureus: a single approach developed by consensus in 10 European
laboratories and its application for tracing the spread of related strains. J Clin Microbiol 2003, 41:1574–1585. 15. Francois P, Renzi G, Pittet D, Bento M, Lew D, Harbarth S, Vaudaux P,
Schrenzel J: A novel multiplex real-time PCR assay for rapid typing of
major staphylococcal cassette chromosome mec elements. J Clin
Microbiol 2004, 42:3309–3312. 16. Swedish Institute for Communicable Disease Control: SWEDRES 2011. A
report on Swedish antibiotic utilisation and resistance in human medicine. 2012. http://www.smittskyddsinstitutet.se/upload/Publikationer/SWEDRES-
SVARM-2011_2012-15-3.pdf. Submit your next manuscript to BioMed Central
and take full advantage of:
• Convenient online submission
• Thorough peer review
• No space constraints or color figure charges
• Immediate publication on acceptance
• Inclusion in PubMed, CAS, Scopus and Google Scholar
• Research which is freely available for redistribution
Submit your manuscript at
www.biomedcentral.com/submit Submit your next manuscript to BioMed Central
and take full advantage of:
• Convenient online submission
• Thorough peer review
• No space constraints or color figure charges
• Immediate publication on acceptance
• Inclusion in PubMed, CAS, Scopus and Google Scholar
• Research which is freely available for redistribution
Submit your manuscript at
www.biomedcentral.com/submit 17. Cuny C, Layer F, Strommenger B, Witte W: Rare occurrence of methicillin-
resistant Staphylococcus aureus CC130 with a novel mecA homologue in
humans in Germany. PLoS One 2011, 6:e24360. Submit your next manuscript to BioMed Central
and take full advantage of: Submit your next manuscript to BioMed Central
and take full advantage of: 18. References 1. Deurenberg RH, Stobberingh EE: The evolution of Staphylococcus aureus. Infec Genet Evol 2008, 8:747–763. 1. Deurenberg RH, Stobberingh EE: The evolution of Staphylococcus aureus. Infec Genet Evol 2008, 8:747–763. 2. Weese JS, Van Duijkeren E: Methicillin-resistant Staphylococcus aureus and
Staphylococcus pseudintermedius in veterinary medicine. Vet Microbiol
2010, 140:418–429. As part of the surveillance of antimicrobial resistance
in mastitis pathogens from dairy cows in Sweden, several
studies have been performed during the last ten years
without findings of MRSA. Isolates in these studies have 3. van der Wolf PJ, Rothkamp A, Junker K, De Neeling AJ: Staphylococcus
aureus (MSSA) and MRSA (CC398) isolated from post-mortem samples
from pigs. Vet Microbiol 2012, 158:136–141. p g
4. Vanderhaeghen W, Cerpentier T, Adriaensen C, Vicca J, Hermans K, Butaye P:
Methicillin-resistant Staphylococcus aureus (MRSA) ST398 associated with 4. Vanderhaeghen W, Cerpentier T, Adriaensen C, Vicca J, Hermans K, Butaye P:
Methicillin-resistant Staphylococcus aureus (MRSA) ST398 associated with Page 3 of 3 Page 3 of 3 Unnerstad et al. Acta Veterinaria Scandinavica 2013, 55:6
http://www.actavetscand.com/content/55/1/6 Unnerstad et al. Acta Veterinaria Scandinavica 2013, 55:6
http://www.actavetscand.com/content/55/1/6 Kriegeskorte A, Ballhausen B, Idelevich EA, Kock R, Friedrich AW, Karch H,
Peters G, Becker K: Human MRSA isolates with novel genetic homolog,
Germany. Emerg Infect Dis 2012, 18:1016–1018. • Convenient online submission • Thorough peer review doi:10.1186/1751-0147-55-6
Cite this article as: Unnerstad et al.: Methicillin-resistant Staphylococcus
aureus containing mecC in Swedish dairy cows. Acta Veterinaria
Scandinavica 2013 55:6.
|
https://openalex.org/W2522457843
|
https://pubs.rsc.org/en/content/articlepdf/2016/cs/c6cs00395h
|
English
| null |
Metal–organic frameworks as competitive materials for non-linear optics
|
Chemical Society reviews
| 2,016
|
cc-by
| 21,799
|
Metal–organic frameworks as competitive
materials for non-linear optics Cite this: Chem. Soc. Rev., 2016,
45, 5408 Cite this: Chem. Soc. Rev., 2016,
45, 5408 L. R. Mingabudinova,a V. V. Vinogradov,a V. A. Milichko,a E. Hey-Hawkins*b and
A V Vi
d
*a L. R. Mingabudinova,a V. V. Vinogradov,a V. A. Milichko,a E. Hey-Hawkins*b and
A. V. Vinogradov*a The last five years have witnessed a huge breakthrough in the creation and the study of the properties of
a new class of compounds – metamaterials. The next stage of this technological revolution will be the
development of active, controllable, and non-linear metamaterials, surpassing natural media as platforms for
optical data processing and quantum information applications. However, scientists are constantly faced with
the need to find new methods that can ensure the formation of quantum and non-linear metamaterials with
higher resolution. One such method of producing metamaterials in the future, which will provide scalability
and availability, is chemical synthesis. Meanwhile, the chemical synthesis of organized 3D structures with a
period of a few nanometers and a size of up to a few millimeters is not an easy task and is yet to be
resolved. The most promising avenue seems to be the use of highly porous structures based on metal–
organic frameworks that have demonstrated their unique properties in the field of non-linear optics (NLO)
over the past three years. Thus, the aim of this review is to examine current progress and the possibilities of
using metal–organic frameworks in the field of non-linear optics as chemically obtained metamaterials of
the future. The review begins by presenting the theoretical principles of physical phenomena represented by
mathematical descriptions for clarity. Major attention is paid to the second harmonic generation (SHG)
effect. In this section we compare inorganic single crystals, which are most commonly used to study the
effect in question, to organic materials, which also possess the required properties. Based on these data,
we present a rationale for the possibility of studying the non-linear optical properties of metal–organic
structures as well as describing the use of synthetic approaches and the difficulties associated with them. The second part of the review explicitly acquaints the reader with a new class of materials which successfully
combines the positive properties of organic and inorganic materials. a ITMO University, St. Petersburg, 197101, Russian Federation.
E-mail: avv@scamt.ru
b Leipzig University, Faculty of Chemistry and Mineralogy, Institute of Inorganic
Chemistry, D-04103 Leipzig, Germany. E-mail: hey@uni-leipzig.de Metal–organic frameworks as competitive
materials for non-linear optics Using recently synthesized metal–
organic frameworks and coordination polymers in the field of non-linear optics as an example, we consider
synthetic approaches used for obtaining materials with desired properties and the factors to be considered
in this case. Finally, probable trends towards improving the quality of the synthesized materials with regards
to their further use in the field of non-linear optical effects are described. Received 21st May 2016
DOI: 10.1039/c6cs00395h
www.rsc.org/chemsocrev Received 21st May 2016
DOI: 10.1039/c6cs00395h when studying the interaction of radiation with matter involved
light sources with a small capacity and providing an intensity of the
order of 1–10 W cm2 and achievable light fields of 0.1–10 V cm1
as a result, it was believed that the investigated experimental
characteristics did not depend on the radiation intensity. The
proposed assertion can be attributed to the field of linear optics,
where the dielectric constant e and the magnetic susceptibility w
are treated as independent of the intensity of electromagnetic
waves propagating in the medium, which corresponds to a linear
relationship between the polarization vector P and the electric
field strength E (Fig. 1(a)).1 However, with the advent of laser
sources with an intensity of 1010 W cm2 and the resulting
field of about 107 V cm1, one cannot neglect an intra-atomic
field which is of the order of e/ro
2 B 109 V cm1 (ro is the
characteristic radius of an electronic orbital, which is equal to a
value of about 108 cm). Cite this: Chem. Soc. Rev., 2016,
45, 5408
Received 21st May 2016
DOI: 10.1039/c6cs00395h
www rsc org/chemsocrev
Chem Soc R
REVIEW ARTICL
p
p
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Cite this: Chem. Soc. Rev., 2016,
45, 5408
Received 21st May 2016
DOI: 10.1039/c6cs00395h
www rsc org/chemsocrev
Chem Soc R
REVIEW ARTICL
p
p
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Chem Soc Rev This journal is © The Royal Society of Chemistry 2016 Review Article He
received a MS Degree in materials
science from the Ivanovo State
University
of
Chemistry
and
Technology
in
2007. He
was
awarded
a
PhD
in
inorganic
chemistry from the Institute of
Solution Chemistry of RAS (with
Professor Alexander V. Agafonov)
in
2010. Thereafter,
he
did
postdoctoral training in materials
science
in
Prof. David
Avnir’s
research group at the Hebrew
University of Jerusalem. In 2014, he joined ITMO University, where
he started as a Head of the Laboratory of Solution Chemistry of
Advanced Materials & Technologies. V. V. Vinogradov L. R. Mingabudinova
Leila Mingabudinova received her
BSc degree from Saint Petersburg
State University, Saint Petersburg,
Russia, in 2015. She has prepared
her Master’s thesis at the Inter-
national
Laboratory
‘‘Solution
Chemistry of Advanced Materials
and
Technologies’’,
led
by
Alexandr
Vinogradov,
ITMO
University,
Saint
Petersburg,
Russia, and partially at Leipzig
University, Faculty of Chemistry
and
Mineralogy,
Institute
of
Inorganic Chemistry, led by Prof. Dr. Evamarie Hey-Hawkins, Leipzig, Germany. Her current research
interests include the synthesis of new MOFs and their biological
applicability and non-linear optical effects. L. R. Mingabudinova
Leila Mingabudinova received her
BSc degree from Saint Petersburg
State University, Saint Petersburg,
Russia, in 2015. She has prepared
her Master’s thesis at the Inter-
national
Laboratory
‘‘Solution
Chemistry of Advanced Materials
and
Technologies’’,
led
by
Alexandr
Vinogradov,
ITMO
University,
Saint
Petersburg,
Russia, and partially at Leipzig
University, Faculty of Chemistry
and
Mineralogy,
Institute
of
Inorganic Chemistry, led by Prof. Dr. Evamarie Hey-Hawkins, Leipzig, Germany. Her current research
interests include the synthesis of new MOFs and their biological
applicability and non-linear optical effects. L. R. Mingabudinova L. R. Mingabudinova V. V. Vinogradov V. V. Vinogradov V. A. Milichko V. A. Milichko
Valentin
A. Milichko
is
an
Assistant
Professor
at
ITMO
University, Department of Nano-
photonics and Metamaterials. He
received his PhD in laser physics
from the Institute of Automation
and Control Processes, Russian
Academy of Sciences, in 2014
and was a postdoctoral member
of ITMO University during 2014–
2016. His research focuses on
the non-linear optics of metal–
organic solids and biomolecules. E. Hey-Hawkins
Evamarie Hey-Hawkins received
her doctoral degree (1983) at the
University of Marburg, Germany. After stays at the University of
Sussex,
UK,
the
University
of
Western Australia and the ANU,
Canberra, Australia, she returned
to Germany and completed her
habilitation
(Marburg,
1988). 1.1
A brief introduction to non-linear optics Before proceeding to the consideration of current trends in the
field of materials used for non-linear optics, one should be
familiar with the existing theoretical propositions in order to
have an understanding of the processes observed in the studies
of the corresponding effects. When considering the interaction of a light wave with matter,
we introduce the polarization vector P, which is a function of the
strength of the electric field of the light wave: P = f (E). At a time This journal is © The Royal Society of Chemistry 2016 5408 | Chem. Soc. Rev., 2016, 45, 5408--5431 View Article Online Review Article Review Article Chem Soc Rev the polarization P expansion in powers of the electric field of the
light wave. The material polarization component, which occurs
in the second term of the equation, can be expressed as follows: In such an analysis, an equation relating the electric field
strength and polarization can be generally represented by
expanding as a series: P = kE + wEE + WEEE + , P(2) = 1/2e0(w(2)E0
2) + (w2E0
2 cos(2ot)) It can be seen that polarization has a single permanent com-
ponent and another component at a frequency of 2o. The value
of w is the quadratic non-linear polarizability of a substance. The prerequisite for the second harmonic generation (SHG,
doubling of the incident light frequency) is an inequality of w to
zero. These conditions are achieved in anisotropic substances
that do not have a center of symmetry. In the case of a medium
being isotropic or having a center of symmetry, a change in the where the first term represents the linear component, and the
other terms belong to the non-linear polarization components. Such a presentation of the expansion equation is rather condi-
tional, since the values of k, w, W are tensors of the 2nd, 3rd and
higher ranks. cess Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Changing the degree of intensity and exposure time also
affects the change of the light wave field over time E(t) = E0 cos(ot). The second harmonic originates from the quadratic term wEE of Open Access Article. Published on 20 September 2016. Downloaded on 10/24
This article is licensed under a Creative Commons Attribution V. V. Vinogradov
Vladimir Vinogradov was born in
Ivanovo,
Russia,
in
1985. He
received a MS Degree in materials
science from the Ivanovo State
University
of
Chemistry
and
Technology
in
2007. He
was
awarded
a
PhD
in
inorganic
chemistry from the Institute of
Solution Chemistry of RAS (with
Professor Alexander V. Agafonov)
in
2010. Thereafter,
he
did
postdoctoral training in materials
science
in
Prof. David
Avnir’s
research group at the Hebrew
University of Jerusalem. In 2014, he joined ITMO University, where
he started as a Head of the Laboratory of Solution Chemistry of
Advanced Materials & Technologies. V. V. Vinogradov
Vladimir Vinogradov was born in
Ivanovo,
Russia,
in
1985. This journal is ©The Royal Society of Chemistry 2016 Chem. Soc. Rev., 2016, 45, 5408--5431 | 5409 where k is a wave vector. Second harmonic generation is a special case of the total
frequency generation o1 + o2 = o3, in which waves of the same
frequency enter a medium, and the total radiation is o + o = 2o. The conditions of phase synchronism for the case when the
wave vectors are collinear can be written in terms of wave
numbers as follows: There are several classes of crystals lacking a center of
symmetry for which n1o|o = ne
2(y)|2o in the case of propagation
of waves with frequencies o and 2o at the angle qc with respect
to the optical axis of the crystal. The angle between the optical
axis of a non-linear crystal and the wave vectors of the interacting
waves is called the phase (wave and spatial) synchronism angle. As an example of practical application, Fig. 3 demonstrates
several configurations for second harmonic generation in bulk
materials and in waveguides, in which infrared light is converted
into visible light and visible light into ultraviolet radiation. There are several classes of crystals lacking a center of
symmetry for which n1o|o = ne
2(y)|2o in the case of propagation
of waves with frequencies o and 2o at the angle qc with respect
to the optical axis of the crystal. The angle between the optical
axis of a non-linear crystal and the wave vectors of the interacting
waves is called the phase (wave and spatial) synchronism angle. Ko + ko = k2o As an example of practical application, Fig. 3 demonstrates
several configurations for second harmonic generation in bulk
materials and in waveguides, in which infrared light is converted
into visible light and visible light into ultraviolet radiation. when the wave propagates in a medium with a refractive index
n, then k = 2pn/l. when the wave propagates in a medium with a refractive index
n, then k = 2pn/l. Taking into account the phase synchronism, we obtain
no + no = 2n2o. Thus, it is necessary to keep the condition
no = n2o in a non-linear medium. According to Neumann’s principle, the symmetry of a physical
property must coincide with the crystal symmetry, so centro-
symmetric crystals cannot possess the properties described by
polar tensors of odd ranks. Thus, centrosymmetric crystals
cannot have pyro- and piezoelectric, linear electrooptical prop-
erties, optical activity, etc. Alexandr V. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Fig. 1
Relationship between the E and P vectors in a linear medium (a)
and in a non-linear medium (b). 1.2
Phase synchronism conditions Interaction between light beams (o1 and o2) inside matter can
result in the generation of beams with a sum (or difference)
frequency (o3). The most effective case when the resulting
frequency o3, attributable to the given element of volume from
the preceding elements, corresponds to the desired phase of
the radiation at the same frequency generated in this volume
element. In this case, the intensity of generation will increase
by several orders of magnitude, since the process of accumula-
tion takes place throughout the non-linearity of the medium,
which is fulfilled under the conditions of phase (wave and
spatial) synchronism between beams’ wave vectors: Typically, in media with normal dispersion, such a condition
is not fulfilled, since the function n(o) increases with increasing
frequency. There are several ways to overcome it. Among them,
the use of crystals with birefringence has the greatest practical
importance. In such a crystal, one chooses a propagation direc-
tion for which the refractive index of an ordinary ray with
the main frequency is equal to the refractive index of an extra-
ordinary ray of the second harmonic. Fig. 2 schematically shows
a cross-section of refractive index surfaces (refractive index
indicatrix) for a negative uniaxial crystal, i.e. that for which at
a given fixed frequency ne o no (Fig. 2). The current values of
extraordinary refractive indices (at an arbitrary angle Y between
the wave vector and the optical axis of the crystal) are indicated
by the superscript ‘‘e’’: ne. k1 + k2 = k3, where k is a wave vector. where k is a wave vector. This journal is © The Royal Society of Chemistry 2016 Review Article From 1988 to 1990 she was a
Research Associate at the Max
Planck Institute for Solid State
Research,
Stuttgart,
Germany,
then
a
Heisenberg
fellow
at
Technical University Karlsruhe, Germany (1990–1993). Since 1993,
she has a Chair in Inorganic Chemistry at Universita¨t Leipzig,
Germany. Since October 2013, she has been the Chair of the COST
Action ‘‘Smart Inorganic Polymers’’ (CM1302, SIPs, www.sips-cost. org). Her scientific interests are in the field of organophosphorus
chemistry, biologically active boron compounds and transition metal
complexes for applications in catalysis and materials science. Valentin
A. Milichko
is
an
Assistant
Professor
at
ITMO
University, Department of Nano-
photonics and Metamaterials. He
received his PhD in laser physics
from the Institute of Automation
and Control Processes, Russian
Academy of Sciences, in 2014
and was a postdoctoral member
of ITMO University during 2014–
2016. His research focuses on
the non-linear optics of metal–
organic solids and biomolecules. E. Hey-Hawkins E. Hey-Hawkins E. Hey-Hawkins E. Hey-Hawkins V. A. Milichko Chem. Soc. Rev., 2016, 45, 5408--5431 | 5409 This journal is ©The Royal Society of Chemistry 2016 Fig. 1
Relationship between the E and P vectors in a linear medium (a)
and in a non-linear medium (b). Review Article
View Article Online Chem Soc Rev Review Article direction of the applied electric field E would lead to a change
in the sign of the polarization P, which implies that the
components of the equation containing even powers in the
expansion should not contribute to the total value, i.e., should be
equal to zero. If the frequencies are doubled, a medium should
have no absorption for all interacting waves. Consequently, the
second harmonic generation is determined by the symmetry of
the crystal structure; therefore, compounds without a center of
inversion are suitable for studying this effect. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Fig. 3
Demonstration of the second harmonic in the visible region using
different types of inorganic crystals. Adopted from ref. 1 (Copyright r
2000-2016 by John Wiley & Sons, Inc.). Investigations on non-linear optical properties of the low-
temperature modification b-BaB2O4 (BBO) of barium borate
started in the 1980s. The lack of a center of symmetry in this
crystal provides a number of interesting properties, such as
second harmonic generation with high efficiency (approximately
6 times greater than that of potassium dihydrogen phosphate),
a high laser damage threshold, and large birefringence.2,3 Single
crystals of BBO found applications in optoelectronics for conversion
of the laser light frequency according to the mechanism of genera-
tion of second and higher harmonics. Electronic delocalization in
complex boron–oxygen anions leads to the presence of non-linear
optical properties in their single crystals.4–7 The high polariz-
ability of borate crystals caused by the peculiarities of their
electronic structure is comparable to the polarizability of
organic aromatic compounds.8,9 The above fact is used to quickly examine the presence of
second harmonic generation upon irradiation with a laser beam. Hence, the existence of the piezoelectric effect and second
harmonic generation allows for an unequivocal conclusion that
a substance is non-centrosymmetric; if the effect is expected but
not observed, then the effect is apparently just too weak. The above fact is used to quickly examine the presence of
second harmonic generation upon irradiation with a laser beam. Hence, the existence of the piezoelectric effect and second
harmonic generation allows for an unequivocal conclusion that
a substance is non-centrosymmetric; if the effect is expected but
not observed, then the effect is apparently just too weak. Observation of electrooptical and magnetooptical effects
(dependence of the refractive index on static electric or magnetic
fields) corresponds to the case of quadratic non-linearity if one
of the fields is permanent. These effects are significant in
an important class of photovoltaic and photorefractive effects. For example, in a number of semiconductors the influence of
radiation results in a spatial separation of oppositely charged
carriers (electrons and holes). This gives rise to an electrostatic
field with a change in the permittivity tensor. The nature of the chemical bonds in the system (Fig. 4) is
shown for a better understanding of non-linear optical proper-
ties in further studies of single crystals using metal–organic
frameworks as an example. The sp2 hybridized boron in cyclic
anions (Fig. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 4a and b) interacts with an oxygen atom, providing
a vacant orbital for the filled orbitals of the oxygen atoms,
resulting in the formation of a p-bond within the ring. The
interaction between the barium cations and borate anions is
electrostatic; there is an intermolecular interaction10 between
electrically neutral layers. One of the major limitations in practical terms is that there
are hardware limitations for studying non-linear optical proper-
ties of a material. Consequently, for many years research was
mainly focused on the measurements of macro-objects as the
transition to the micro level was limited by this problem. However, it is the field of micro-objects that will undergo further
development of non-linear optics as successfully demonstrated
in several studies using synthesized materials as an example. Switching to the said level is also interesting with regards to the
fact that it is possible to make an assumption where structural
units are largely responsible for the observed effect. In addition
to this, it is worth noting that the material should also be
resistant to laser radiation within a predetermined range to
avoid thermal degradation. Thus, attention should turn to
synthetic approaches, which facilitate obtaining the desired
structure, and then to techniques for modifying the material to
render it suitable for the process of investigation. The mechanical properties and resistance to laser radiation
present in inorganic crystals are typical of these types of single
crystals as well. Single crystals of borates are usually grown
using the Czochralski method10 or by direct recrystallization of
the cooled melt. However, a tendency towards vitrification signifi-
cantly complicates the process of growth. Moreover, low yields Fig. 4
Structural units that make up borate crystals: (a) B3O6, (b) B3O7,
(c) BO3, and (d) BO4. Adapted from ref. 10 (with permission from Copyright r
Royal Society of Chemistry 2016). This journal is ©The Royal Society of Chemistry 2016 where k is a wave vector. Vinogradov obtained
his PhD degree from the Ivanovo
State University of Chemistry and
Technology (ISUCT) in 2011. He
spent some time as a postdoc at
Leipzig University, Germany, in
the
group
of
Prof. Evamarie
Hey-Hawkins. In 2014, he joined
ITMO University, where he is
currently associate professor. His
specific interests are in the field
of
bioapplication
and
optical
properties of MOFs, photoactive
thin films and inkjet printing of
optical nanostructures. A. V. Vinogradov Fig. 2
The conditions of synchronism in a uniaxial crystal. Fig. 2
The conditions of synchronism in a uniaxial crystal. 5410 | Chem. Soc. Rev., 2016, 45, 5408--5431 This journal is © The Royal Society of Chemistry 2016 View Article Online View Article Online Fig. 3
Demonstration of the second harmonic in the visible region using
different types of inorganic crystals. Adopted from ref. 1 (Copyright r
2000-2016 by John Wiley & Sons, Inc.). Review Article Chem Soc Rev which successfully combine the properties of both organic and
inorganic components. 1.3.1
Inorganic materials. The non-centrosymmetric structure
of inorganic crystals allows them to be used in investigations in the
field of non-linear optics. The species particularly suitable for
measuring characteristics are potassium dihydrogen phosphate,
barium b-borate, and lithium niobate. For these crystals, values
of w from 1 to 100 109 ESU were obtained due to the high
electronic polarizability associated with the band structure of
the crystal and its asymmetry. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. w(2) = NbF
and
w(3) = NgF. How is it possible to increase the molecular non-linear
susceptibility b and g without specific physical treatment like
coherent excitation? From the theory of a two-level model of a
molecule (the ground state is g, excited is n) it follows that the
value of b depends on the oscillator strength ( f ) for the g–n
transition, frequency ho0, and a change in dipole moment in
the transition from the ground state to the excited state, Dm. The donor–acceptor molecule of p-nitroaniline ( p-na) can serve
as an example of a molecule widely used in non-linear optics. The donor here is the NH2 group, the acceptor is the NO2
group, and both groups are linked with the conjugated carbon
system (namely, the aromatic ring) (Fig. 5). This crystal is grown by pulling from the melt. It is resistant
to moisture but its linear dimensions with the necessary optical
quality are substantially smaller than those of KDP. The radia-
tion resistance is not inferior to the latter. The quality factor for lithium niobate is higher than that of
KDP, but a fairly high temperature dependence of the refractive
index n(T) and a slightly higher level of absorption in the
transparent region lead to a breach of the phase synchronism
conditions. This is due to the rapid heating of the crystal under
the action of radiation with extremely high intensity, such as
radiation using fusion devices. However, due to this tempera-
ture dependence, lithium niobate allows for convenient 901
tangent SHG synchronism for radiation with a wavelength of
about 1 mm upon thermostating it at a temperature of 70–90 1C. To produce molecules with large values of b, one should
select the strongest donor (–NH2, –NMe2) and acceptor (–CN,
–NO2) groups and increase the conjugated bond length between
molecules. The transition from such dipole molecules to the
bulk material with high non-linear polarizability w(2) is investi-
gated while considering the structure of the material. The
problem is that in most cases of crystallization the dipole
molecules line up in such a way that their dipole moments
are oppositely directed. In this case, the total optical polariz-
ability is close to zero. However, there are several ways to solve
this problem. 5412 | Chem. Soc. Rev., 2016, 45, 5408--5431 Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. One is to coat thin ordered molecular layers using
the
Langmuir–Blodgett
method,
whereby
monomolecular
layers are applied sequentially so that the dipole moments of
the molecules are directed in the same direction. The optical quality of the crystals during growth may be
impaired as a result of morphological instability, impurity
contents, inclusions in the structure (due to the peculiarities
of synthesis), viscosity, and tendency to vitrification for some
systems.10 1.3.3
Organic chromophores. One of the most successful
approaches to overcome the existing shortcomings in inorganic
materials is the use of organic chromophores as an alternative. At the same time, the processes of growing such crystals are
usually difficult and extremely energy intensive. The synthesis
is carried out under high vacuum or in an inert atmosphere at a
pressure of up to 1700 atm, and also requires a temperature
ranging from 600 to 900 1C. In addition, it may take 10 days to
8 weeks to obtain a crystal of the size 20 mm 20 mm 60 mm. Moreover, of utmost importance is the fact that these methods
do not allow the creation of a new design of structures, thereby
limiting their potential use. Additional constraints are imposed
due the low stability in the presence of atmospheric moisture. Scientists have achieved impressive results in this area. However, the creation of materials with directional optical
properties remains an extremely difficult task to solve. Therefore,
the majority of approaches to the preparation of materials based
on chromophores rely purely on the chemical intuition of the
researchers. In recent decades, heterocyclic fragments have Fig. 5
Molecular structures for the ground and excited states and the
degree of charge transfer from donor to acceptor in the ground and
excited states. 1.3.2
Organic materials. Organic materials possess high
non-linear optical susceptibility due to increased polarizability
of the p-electron cloud in conjugated systems. Upon applying
small fields, the arising charge displacement leads to a non-
linear response, which in turn leads to a modulation of the
refractive index. In addition, polarization being purely electronic
in nature has a response time of about one femtosecond or less. Fig. 5
Molecular structures for the ground and excited states and the
degree of charge transfer from donor to acceptor in the ground and
excited states. This journal is © The Royal Society of Chemistry 2016 1.3
The appearance of NLO in different media Since the attention of scientists has been focused on investigat-
ing various non-linear optical effects, entire classes of materials
have been studied. However, it is worth noting that every
material has its drawbacks. On the way to obtaining a material
devoid of these deficiencies, the attention was shifted to
organic materials. However, they also have failed to fully satisfy
technical needs due to their high instability. Thus, the present
time is characterized by a growing interest in hybrid materials, Fig. 4
Structural units that make up borate crystals: (a) B3O6, (b) B3O7,
(c) BO3, and (d) BO4. Adapted from ref. 10 (with permission from Copyright r
Royal Society of Chemistry 2016). Chem. Soc. Rev., 2016, 45, 5408--5431 | 5411 This journal is ©The Royal Society of Chemistry 2016 View Article Online Chem Soc Rev Review Article Review Article Review Article of suitable materials, undesirable variations in crystal proper-
ties, and energy consumption of production processes, ulti-
mately lead to high costs of the finished optical elements. distance between the molecules is much smaller than the
wavelength of the incident light, the volumetric non-linear
coefficient can be considered as the sum of dipoles (in non-
coherent regime) with some correction (F), taking into account
the mutual orientation of the molecules.1 Thus, the bulk values
of non-linear coefficients w(2) and w(3) can be expressed in terms
of corresponding molecular coefficients b and g. In this case, we
obtain expressions in the form: Another inorganic crystalline compound used in non-linear
optics is potassium dihydrogen phosphate, KH2PO4 (KDP). This
is a single-axis, negative piezoelectric crystal with the symmetry
class %42m. Its advantages include high radiation resistance (it is
not destroyed when exposed to extremely high intensities of
light radiation), relatively low level of absorption in the trans-
parent region, and weak temperature dependence n(T) of the
refractive index. However, there is a serious drawback in its
practical application: the hygroscopy of the crystals, which
requires certain measures when working with this material. Among the second class of inorganic crystals one can distinguish
lithium niobate, LiNbO3, another uniaxial negative piezoelectric
crystal with the symmetry class 3m and a transparency range of
0.4–5 mm. The refractive indices of the crystal greatly depend on
the temperature n(T) of the sample. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. In organic materials, each molecule should be considered as
a separate dipole with non-linear polarization, and if the This journal is © The Royal Society of Chemistry 2016 View Article Online Review Article Chem Soc Rev been considered to be promising for chromophores, in parti-
cular as elements for the p conjugation. Moreover, theoretical
calculations have already been performed for chromophores
possessing one or more thiophene as well as triazole, pyrrole or
furan rings. between atoms in unsaturated fragments of a molecule. In this
case, the electrons are delocalized and easily move under the
influence of electric fields. Electron donor and acceptor groups
located at opposite ends of a molecule are responsible for
asymmetry (pull–push effect). These groups provide a permanent
dipole moment, causing the induction of a total dipole moment,
which ultimately leads to the asymmetry of the system. Increasing
the strength of the donor/acceptor and the length of the
conjugated chain between these groups leads to an increase
in the hyperpolarizability, which is similar to what happens for
the first-order dipole moment for two static charges. To achieve high coefficients in non-linear optical properties,
an optimal choice of the electron donor/acceptor in the system
is necessary, which also poses a challenge for researchers at the
moment. In recent years, major attention has been focused on
electron bridges in the chromophore structure and the proper-
ties of the acceptor with no emphasis on the properties of the
donor, although it also affects the final characteristics of the
system. The class of alkyl and aryl amines, which have a lone
pair of electrons on nitrogen suitable for interacting with the p*
orbital of the aromatic ring, turned out to be the most success-
ful for applications. Perhaps this was the reason that prompted
scientists to pay attention to the introduction of additional
heteroatoms in the fragments of the chromophore donor, which
sharply modulates conjugation of the p-electron system and
changes the kinetics of charge transfer, affecting in turn the
first-order hyperpolarizability of the chromophores. Moreover,
the introduction of heteroatoms in the structure allows for
further synthetic modification. However, it should be borne in
mind that in this case the problem of obtaining a quality product
as a result of a multi-stage chemical synthesis still persists. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. For use in non-linear optics, the optically inactive polymer is
doped with a chromophore employing mechanical methods
(deposition). However, such a technique does not provide an
ordered orientation of the chromophore; the result of which is
a value of zero for w2. To solve this problem, a tape with built-in
chromophore molecules is heated above the temperature
of vitrification (in most cases from 100 to 200 1C), thereby
providing some degree of orientational mobility for the chromo-
phore molecules. For the purpose of orientation of the molecules
in the direction of the electric field, strong fields of the order of
105–106 V m1 are used. The order in the system is then ‘‘frozen’’
by lowering the temperature. This approach yields a value of
108 to 107 ESU for w2.12 The main problem is instability over
time due to randomization of the chromophore molecules. A sharp decay is possible at the beginning of the use of certain
systems at room temperature even on the first day. However, this
problem can be somewhat reduced by crosslinking polymers in
which photoactive groups can form bonds upon ultraviolet
irradiation thus preventing orientational mobility of the
polymer. Crosslinked polymers in this case demonstrate a smaller
w2 than non-crosslinked ones, but the decay rate is greatly
reduced.13 In addition, it is possible to increase the stability
of chromophores through the use of polyimides in order to
reduce orientational mobility of the polymer structure.14,15 It is
also possible to use polyamic acid which can be attached as a
pendant group. When heated above 250 1C, the compound
undergoes condensation with the formation of an imide ring,
which limits the allowable motion of chromophores and
increases the thermal stability of the material. Then, the
process of sealing the film is carried out at a temperature of
about 350 1C, which reduces the film thickness to 40%,14
further limiting the mobility of the guest molecules. Examples of such solutions could be provided by the creation
of a series of chromophores11 with one or two heteroatoms in the
ortho position relative to the p bridge, where more efficiently
conjugation of these heteroatoms with the p system may occur. For correct comparison of the properties of chromophores,
2-dicyanomethylene-3-cyano-4,5,5-dimethyl-2,5-dihydrofuran (tcf)
can be used as an electron acceptor in each system. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Thus, due to the presence of the strong donor group (E)-2-(4-
(2,4-bis(diethylamino)styryl)-3-cyano-5,5-dimethylfuran-2(5H)-
ylidene)malononitrile, this chromophore type showed the
greatest polarizability in the series compared to the rest. The
chromophore showed a small dihedral angle 3.101, whereas 3-(E)-
2-(3-cyano-4-(2-ethoxy-4,6-di(pyrrolidin-1-yl)styryl)-5,5-dimethyl-
furan-2(5H)-ylidene)malononitrile, which showed the lowest
hyperpolarizability, has a corresponding angle of 221. Thus, a
low value of b is observed due to a large torsion angle between
the acceptor group and the benzene ring, which prevents
effective p conjugation. It should be noted that despite the fact that thermal treat-
ment increases the thermal stability of the resulting film, it is
important to bear in mind that the decay temperature for the
majority of non-linear chromophores is significantly lower than
the temperature required for processing. The obvious disadvantages of organic chromophores are
multistage syntheses, the need for product purification after
each stage to avoid isomerization of initial compounds in an
undesired phase, very low yields of the isolated product, low
solubility in common solvents used for the crystallization of the
material, and the aggregation of some of the compounds in the
solution, which again complicates the process of separation and
purification of the final product. Ultimately, everything leads to a
significant loss of material and an increase in its cost.11 This journal is ©The Royal Society of Chemistry 2016 Chem. Soc. Rev., 2016, 45, 5408--5431 | 5413 Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Molecules with greater hyperpolarizability possess higher
efficiency of charge transport in an optically excited state,
resulting in a large difference between the ground and excited
states of the dipole moments. These excitations involve p–p*
transitions in one predominant direction.17 It generally refers
to the direction of the dipole moment of a molecule having a
cylindrical symmetry. In LB films such a molecule is tilted at an
angle F with respect to the surface normal. It turns out that the
molecules in the Langmuir–Blodgett films are highly oriented,
causing a change in the local optical field. For example, it has
been shown that interface nonlinearity is represented by a local
(or electric dipole allowed) surface nonlinear susceptibility
tensor.18,19 This is due to the induced dipole–dipole interaction
between the molecules. 1.4.2
Covalent self-assembly. Systems of self-assembled
monolayers, or so-called chemisorbed films, can cope with some
drawbacks of the Langmuir–Blodgett technique. The method
consists of immersing hydroxylated substrates in an amphiphilic
liquid (solution or melt). Thus, covalent attachment to the
surface occurs (Fig. 6). Then, new layers can be applied to the
surface using chemical activation. The main advantage of this technique is the ability to obtain
the desired structural organization of the material. Such
materials exhibit good chemical, thermal and electrical stability,
and can even be additionally crosslinked to improve their
properties for practical use. This technology is a convenient
way of organizing non-centrosymmetricity in the structure. Marks et al. implemented a strategy in which the –SiCl3 groups
were attacked by small molecules and, in an SN2 reaction
mechanism, interacted with molecules of an NLO-active dye.26 Shen and coworkers20–22 pioneered investigations of second
harmonic generation in monolayers. The Heinz group23 studied
the resonant amplification of second harmonic generation from
rhodamine dye molecules adsorbed on the substrate of molten
silicon. By changing the polarization of the incident light and
measuring the output polarization using the corresponding
mathematical equation, they obtained a F value of 301 and a
hyperpolarization of 30 1030 ESU. Self-assembled layers of [2-(p-chloromethylphenyl)ethynyl]-
silane were reacted with [2-[4-[N,N-bis(3-hydroxypropyl)amino]-
phenyl]ethynyl]-40-pyridine. Also, a system has been considered,
produced by applying a thin layer of [[4-[N,N-bis(3-hydroxy-
propyl)amino]phenyl]azo]-40-pyridin, by centrifugation on a sub-
strate modified with benzyl chloride, and subsequent annealing
at a temperature of 110 1C, which yielded a material with a high
degree of organization (Fig. 7). Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. The main difficulty while applying films using the Langmuir–
Blodgett method is in controlling the surface pressure in the
adsorption process and in removing the molecules. Since it is
pressure that is responsible for the dense packing of the
molecules, its decrease may result in lowering of the orientation,
whereas higher pressures may cause the molecules to fold in on
each other, thereby destroying the layer. It is therefore necessary
to maintain a constant pressure in the system. Experiments with alternation of fatty acid molecules that are
inactive in terms of optics proved to be ineffective in contrast
to expectations. In this regard, Neal25 proposed a different
method of alternation of layers, where hemicyanine and amino-
nitrostilbene dyes were used, whose hyperpolarizabilities are
opposite in sign. Thus, despite the fact that the deposition was
performed by Y-type, the values of hyperpolarizabilities were
added. It has been experimentally shown that an amplification
of the second harmonic signal is observed as a result of the
film formation. It has been determined that the w values for
hemicyanine and aminonitrostilbene amount to 300 1030
and 55 1030 ESU, respectively. Evidence of interaction
between the layers was provided by the obtained value of w,
850 1030 ESU for the bilayer, which was significantly larger
than the values of the individual components. In continuation
of a series of experiments, the second harmonic generation for
films consisting of bilayers was investigated which led to
interesting results. It turned out that the obtained dependence
of intensity of the second harmonic generation on the number
of layers was greater than quadratic, which may indicate a
disorder of the multilayer.25 At first glance, the technique is simple because the deposition
process itself does not require a high temperature or an ultrahigh
vacuum. But one should not forget that the very realization of the
experiment requires a cleanroom. Other serious drawbacks of
this advantageous method are the technical complexity of the
procedure and greater sensitivity to environmental conditions. However, the most significant drawback is low mechanical and
thermal stability, since the layers are connected to each other
only by van der Waals forces. Additionally, upon increasing
the heat over time, chromophore disorientation in the layers
may occur. 1.4
Structurally organized materials 1.4.1
Langmuir–Blodgett (LB) films. In the section on organic
materials with NLO properties, we have already revealed the
prospects of using Langmuir–Blodgett films. For structures with large molecular hyperpolarizability, the
system requires the presence of electrons with a highly efficient
response to the electric field, and asymmetry at the molecular
level. Increased polarizability is provided by p–p interaction They consist of molecules, one end of which has a hydro-
philic group and the other a hydrophobic group distributed
on the surface, essentially forming a monolayer. This method Chem. Soc. Rev., 2016, 45, 5408--5431 | 5413 View Article Online Chem Soc Rev Review Article allows the thickness and structure of the final multilayer to be
controlled by layer-by-layer deposition by dipping the substrate
into a solution. For this purpose, the first stage involves the
adsorption of molecules that are inactive from the perspective
of non-linear optics, and the next stage the application of the
chromophore molecules. This approach allowed obtaining non-
linear susceptibility, which was approximately 20 times higher
than that of barium b-borate.16 samples can also be observed for the Z-type films with, for
example, polar films that are not found in nature, as the
molecular dipoles prefer an antiparallel orientation. Another
approach is to study Y-type films with effective molecules in terms
of non-linear optics, which alternate either with non-active mole-
cules or molecules whose hyperpolarizability has the opposite sign. In the latter case, despite the fact that the dipoles are arranged
antiparallel, which is more advantageous in terms of energy,
their hyperpolarizabilities cancel each other out. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Researchers from the Girling group24 studied the processes of
deposition of both monolayer and bilayer films of merocyanine
dye for second harmonic generation. Upon exposing this dye to
air, protonation occurred resulting in loss of non-linear optical
efficiency. For this reason, experiments were performed in an
ammonia atmosphere. The obtained values of w correspond
to 500 1030 ESU. Studies of non-linear optical multilayer With this method it was possible to synthesize a three-layer
arrangement in just one hour. The combined use of self-assembled 5414 | Chem. Soc. Rev., 2016, 45, 5408--5431 This journal is © The Royal Society of Chemistry 2016 View Article Online View Article Online Review Article Chem Soc Rev Chem Soc Rev Fig. 6
An example of a covalent self-assembly process for (dialkylamino)stilbazole on the surface of benzyl chloride-modified silica. The third stage is
the crosslinking between the hydroxyl groups and activation for applying the next layer. Adapted from ref. 29 (with permission from Copyright r 2016
American Chemical Society). Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Fig. 6
An example of a covalent self-assembly process for (dialkylamino)stilbazole on the surface of benzyl chloride-modified silica. The third stage is
the crosslinking between the hydroxyl groups and activation for applying the next layer. Adapted from ref. 29 (with permission from Copyright r 2016
American Chemical Society). an aqueous solution to remove the unbound polymer. The process
is repeated until the desired film thickness is reached. It is not
only possible to obtain a bilayer organization of the material, but
also to alternate layers with different functional properties.31 layers and deposition of thin films by means of centrifugation
is a significant step on the way to application in electrooptical
devices. However, it is worth considering that the process may take
time – from four hours to a few days.27 Also, surface activation
and adsorption processes require elevated temperatures that can
cause disordering of the spatial orientation of the molecules.28
Therefore, the maximum reactivity and organization of the
surface layer are necessary factors. 1.5
Conclusions of the theoretical section As indicated above, various materials used in the field of non-
linear optics have a number of disadvantages, which prompt the
continuing development of new ways of obtaining the desired
characteristics of materials necessary for practical applications. Studies of inorganic materials with non-centrosymmetric struc-
ture, such as quartz, potassium dihydrogen phosphate, barium
b-borate and others, have revealed deficiencies such as a low
NLO response, slow response times, production difficulties, low
optical quality, the absence of extended p-electron delocalization,
and inability to adjust the resulting structure. These deficiencies
have been addressed and resolved using organic materials,
which allowed the formation of centrosymmetric structures
due to dipole–dipole interactions. In addition, the order of
the dipoles in organic materials can be induced by an external
field, ‘‘freezing’’ it with external temperature influences. In this
case, one could obtain a response comparable to or even greater
than that for inorganic crystals. However, these materials have Despite the technical difficulties of the process, some produced
structures demonstrate a susceptibility which is more than 60 times
higher than that observed for barium b-borate crystals.29 1.4.3
Ionic self-assembled monolayer (ISAM) technique. Compared to the method originally proposed in 1992 by
Decher et al.,30 this newly proposed method has a number of
advantages. The method implies an emphasis on the forces of
Coulomb interaction between oppositely charged polymers
forming ultrathin layers. The process itself consists of alternat-
ing cycles of immersion of the substrate in a solution of a
polyelectrolyte with an opposite charge. During immersion the
ions bind to the surface. Some part of the bound groups causes
recharge of the surface, resulting in limitation of the further
attachment of ions. After removal, the substrate is washed with Fig. 7
Formation of a non-centrosymmetric multilayer of a film by combining self-assembly and a surface reaction of SN2 type. Adapted from ref. 28
(with permission from Copyright r 2016 American Chemical Society). Fig. 7
Formation of a non-centrosymmetric multilayer of a film by combining self-assembly and a surface reaction of SN2 type. Adapted from ref. 28
(with permission from Copyright r 2016 American Chemical Society). Chem. Soc. Rev., 2016, 45, 5408--5431 | 5415 This journal is ©The Royal Society of Chemistry 2016 This journal is ©The Royal Society of Chemistry 2016 View Article Online Chem Soc Rev Review Article Fig. 8
Reflectance spectra and optical density of a single crystal of a MOF
irradiated perpendicular to its surface. 2. Metal–organic frameworks These properties hold great promise for use in the manage-
ment of single crystals of MOFs in controlling photoexcitation
under the influence of light, like non-linear and quantum
metamaterials. For example, a highly stable metal–organic fra-
mework based on trinuclear iron(III) secondary building units
(SBUs) linked by tetracarboxylic linkers with an anthracene
core32 may have unique metamaterial properties by ordering
metal atoms (Fe chains) and dielectric elements in one crystal. In general, MOFs are semiconducting or dielectric micro-
crystals whose nodes contain metal ions or polyvalent metal
clusters connected by organic ligands (linkers). These may
comprise both donor and acceptor groups, as well as forming
primary structure elements which give rise to the manifestation
of various physical properties. By combining the components
and varying the synthesis parameters, one can produce a huge
variety of structures for MOFs, thereby affecting the desired
properties of the material. The size and shape of pores of the
formed framework are determined by the length and function-
ality of the organic component.33 Thus, by varying the initial
molecular units, one can obtain final products with different
architectures. One example is the use of heterocyclic molecules
and molecules with hydrocarbon tails which allow for rotation
around its axis, making it difficult to control the metal ion–
ligand environment. In this case, preference is given to rigid
aromatic carboxylate ligands, which possess high chelating 2. Metal–organic frameworks The last 15 years have been characterized by a great boom in
the production and study of metal–organic frameworks and
coordination polymers. These materials have proved to be
excellent sorbents for gases, objects for storing hydrogen (as
fuel), catalysts, elements of analytical devices for separating
substances, as well as demonstrating unique physical proper-
ties in the field of ferroelectricity, non-linear optics, and
magnetism. However, in addition to the existing broad scope
of applications mainly due to a huge surface area, recently also
unique features such as strong optical anisotropy in the visible
region have been studied,32 which were detected via reflection/
absorption spectra (Fig. 8), depending on the direction of the
polarization vector. Fig. 8
Reflectance spectra and optical density of a single crystal of a MOF
irradiated perpendicular to its surface. Red and blue curves correspond
to reflection/absorption of electromagnetic waves with electric vectors E
which are perpendicular (E1) or parallel (E2) to the longest side of the crystal,
as shown in the inset. The slope of the optical density curves supports
different band gaps of the MOF depending on the light polarization (2.7 eV
for E1 and 2.4 eV for E2). Copyright Royal Society of Chemistry. ability, allowing metal ions to be fixed in the nodes of the
produced lattice.34 From a technical point of view, the major drawbacks of the
existing methods for the preparation of MOFs are as follows:
high energy costs, insufficient size of produced single crystals for
studying their structural characteristics, low yield of the expected
product, and labor-intensive methods for the synthesis and
purification of the product. Equally important is instability in
moist air and fragility, which severely limits the possibilities
of practical applications. However, for the application of MOF
crystals in metamaterials the main drawback is the lack of
knowledge and methods for obtaining the order of structures in
the area of more than 5 nm. The first priority questions arising
from numerous studies are what parameters explicitly influence
the produced framework architecture, how they can be corrected,
and what relationships exist between the architecture and
physical characteristics. In an attempt to determine the assumed
relationships, a comparison of methods for the preparation of
metal–organic frameworks with the organization of structures
obtained during synthesis, as well as attempts to establish ways
of developing non-linear optical properties of MOF crystals, is
given below. This journal is © The Royal Society of Chemistry 2016 1.5
Conclusions of the theoretical section Red and blue curves correspond
to reflection/absorption of electromagnetic waves with electric vectors E
which are perpendicular (E1) or parallel (E2) to the longest side of the crystal,
as shown in the inset. The slope of the optical density curves supports
different band gaps of the MOF depending on the light polarization (2.7 eV
for E1 and 2.4 eV for E2). Copyright Royal Society of Chemistry. Review Article poor mechanical strength, poor stability and poor thermal
stability, although they can be easily applied in the form of
films for use in a device. Thus, in order to solve a number of
significant problems with known materials, the main research
focus today is aimed at the study of hybrid materials. The reason
for this is the need to combine the advantages of organic and
inorganic classes of compounds and level their shortcomings. Thus, one of the recent trends in non-linear optics is the
investigation of the so-called metal–organic frameworks (MOFs)
and coordination polymers (CPs), promising as future chemically
derived metamaterials. Huge possibilities in terms of synthesis
of new structures are reinforced with the variability of ions
and clusters that can be used, allowing high precision and
predictability in the properties of the final product. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 2.2
The relationship between the SHG and the size of the
crystal There is evidence that the SHG intensity depends on the crystal
size. For materials such as LiNbO3, where type 1 phase-matching,
or index matching, occurs when the phase velocity of the funda-
mental radiation (1064 nm) equals the second harmonic (532 nm),
the SHG intensity increases with the particle size and eventually
reaches a plateau. In materials with no phase-matching (such
as quartz), the intensity efficiency will reach a maximum value
and then decrease, as the particle size increases. Therefore, the
SHG measurement as a function of particle size is necessary for
more accurate and reliable results.35 Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. The method entails placing the sample in the form of a powder
(about 50 mg) into a cell and irradiation with a low-energy laser
(Fig. 9a). The intensity of second harmonic generation is
measured using a photomultiplier. Results are usually com-
pared with a-quartz. 2.1
Measurements of non-linear optical properties of
metal–organic frameworks The recognized procedures to study the process of second
harmonic generation are the Kurtz and Perry method (1968) 5416 | Chem. Soc. Rev., 2016, 45, 5408--5431 This journal is © The Royal Society of Chemistry 2016 Chem Soc Rev
View Article Online View Article Online View Article Online Review Article Chem Soc Rev for powder samples, Hauchecorne (1971) for measurements
in liquids, as well as for the measurement of individual non-
linearities for molecules in solution, Levine (1976), Oudar
(1977), and finally, Jerphagnon and Kurtz (1970), who improved
the procedure for the investigation of processes occurring in
crystals, known as the Maker-fringe methods. Thus, success-
fully tested techniques for studying molecular, polycrystalline
and single-crystal samples are universal for measuring response
of various materials. The Kurtz and Perry method is the most
frequently used for studying MOFs, despite the fact that powder
analysis does not allow directed excitations along the crystal
planes and thereby limits the analysis of properties in the area of
metamaterials. to the type of crystal and its spatial orientation. This necessi-
tates working in three dimensions with single crystals rather
than powders and multicrystalline samples. We have, therefore,
implemented the concept of optical studies of single crystals of
MOFs (Fig. 9b). The concept is pretty simple, but very useful: a
confocal system for detecting the optical signals (luminescence,
reflection, second harmonic and others) is associated with two
optical channels (or three, for luminescence). The optical channels
can independently move in space due to the mechanical and
optical elements in each channel; the single crystal is on a piezo
stage which allows to locally excite it at any point and angle and
collects the signals from anywhere. The excitation area is
limited by diffraction but the collection area can be much
smaller due to a confocal pinhole. The combination of different
optical elements (Glan–Taylor prisms, quarter-wave plate, immer-
sion objectives, etc.) in the channels allows to perform all optical
experiments with the single crystal consecutively or two experiments
simultaneously (e.g., luminescence and transmission). This system
is well described32 and allows studying non-linear optical
effects (exciton luminescence or birefringence) in different
points of single microcrystals. 3.1
Producing metal–organic frameworks for non-linear
optics The question as to what method can successfully combine
the possibilities of producing the desired crystal structure
(inorganic component) and a variety of synthetic possibilities
of the organic component has been posed by researchers for
several years. The efficiency of generation of second harmonic and other
high-order non-linearities (piezo effect, wave mixing, etc.)
becomes essential with an increase in crystallinity of the
sample. It is due to the fact that generation is directly related The main way to obtain the desired structure in the synthesis
of metal–organic frameworks is the so-called strategy of secondary
building units (SBUs).75 This strategy is based on molecular or Fig. 9
(a) Schematic representation of the Kurtz method for powders. (b) Confocal multifunctional micro-spectroscopy setup for precision optical
measurements with a single crystal of a MOF. The upper and lower channels are for reflectance and transmission measurements that can be upgraded to
simultaneous luminescence measurements. Copyright Royal Society of Chemistry. Fig. 9
(a) Schematic representation of the Kurtz method for powders. (b) Confocal multifunctional micro-spectroscopy setup for precision optical
measurements with a single crystal of a MOF. The upper and lower channels are for reflectance and transmission measurements that can be upgraded to
simultaneous luminescence measurements. Copyright Royal Society of Chemistry. Chem. Soc. Rev., 2016, 45, 5408--5431 | 5417 This journal is ©The Royal Society of Chemistry 2016 Chem. Soc. Rev., 2016, 45, 5408--5431 | 5417 View Article Online Chem Soc Rev ionic assemblies and leads to the formation of secondary
structural units. Non-centrosymmetric organization is a pre-
requisite for the generation of non-linear optical properties of
bulk materials. For conventional methods of producing metal–
organic frameworks, the creation of such non-centrosymmetric
structures is challenging. The most successful SBUs may include
metals connected with chiral ligands, since such materials were
successfully used in selective catalysis and stereoselective
separation.76 Not only can the coordination of the organic ligand
to a metal ion yield an increase in charge transfer transitions,
but it also allows organic chromophores to assemble in highly
ordered geometries like octahedra and tetrahedra, which is
infrequently observed for organic materials. This interaction
produces charge transfer in several directions. In addition, this
is the type of structure that is relatively easy to obtain by
selecting the right combination of metal ions and organic
ligands. Table 1 summarizes various metal–organic frameworks
and coordination polymers obtained by different approaches
and their efficiency in second harmonic generation. 3.2
Ligands Another example is 2-(pyridin-4-yl)-1H-imidazole-4,5-dicarboxylic
acid (H3pidc). In [Zn2(pidc)(H2O)Cl]n the asymmetric unit consists of
two independent zinc ions, one completely deprotonated ligand, one
coordinated water molecule and one coordinated Cl ion (Fig. 12).78
The structure of the material in general is a two-dimensional
grid, while hydrogen bonds allow the dimensionality of the
system to be increased to 3D. A different coordination mode is
observed in [Mn(Hpidc)(H2O)2H2O]n, in which three metal
centers are chelated in an O,O- and N,O-bonding mode as well
as a monodentate coordination of a pyridyl group (Fig. 13),
eventually resulting in a three-dimensional network. Moreover,
the considered structure also forms channels in the [001]
direction filled with non-coordinating water molecules con-
nected via hydrogen bonds. Various coordination modes allow
the pyridine ring and imidazole to take up different positions. The fact that the carboxyl group and the imidazole ring cannot
be located in the same plane ultimately leads to the formation
of a non-centrosymmetric structure.78,79 Coordination of the
ligand increases its rigidity, resulting in a donor–acceptor
system, which is necessary for the manifestation of a non-
linear optical effect. The SHG measurement results showed that
the magnitude of response in the first case was comparable
with urea, while in the second case the value was about 0.8
relative to urea.78 With regard to symmetry, [Zn2(pidc)(H2O)Cl]n
belongs to the class 222 and point group symmetry D2, while
complex [Mn(Hpidc)(H2O)2H2O]n crystallizes in the space
group Cc, which belongs to a polar point group Cs. 3.2.1
Multifunctional ligands. One of the most successful
methods
for
solving
the
problem
of
obtaining
a
non-
centrosymmetric structure of a MOF was using a compound
as a ligand which is capable of chelating a metal ion with
several functional groups in different positions, e.g. deproto-
nated 2-hydroxy-nicotinic acid (nica).77 2-Hydroxy-nicotinic
acid has several potential donor atoms which can allow high-
dimensional structures to be obtained by removing one to
three hydrogen atoms with careful adjustment of the pH of the
medium, leading to various coordination modes. For example,
investigations of second harmonic generation for crystals
obtained by this method, by changing only the stoichiometry
and pH, were reported.78 This in turn leads to different degrees
of ligand deprotonation, ultimately resulting in different coordi-
nation modes upon interaction with two different metal ions. Deprotonated 2-hydroxy-nicotinic acid is capable of coordinat-
ing a metal using different functional groups, yielding four- and
six-membered chelate rings (Fig. 10). This journal is © The Royal Society of Chemistry 2016 3.1
Producing metal–organic frameworks for non-linear
optics and a relatively weak p–p interaction (green dashed line) are
observed between the coordinated and guest bpy ligands. In the
resulting non-centrosymmetric product, which crystallizes in
the space group Fdd2, the polar axis lies along the zig-zag chain
(Fig. 11). Polarity arises due to the location of the bridging
nica2 ligands. For this type of structure, non-linear optical properties were
investigated in accordance with the methods proposed by Kurtz
and Perry. The second harmonic generation intensity measured
in a single crystal using a laser source is lower than that in SiO2,
and the corresponding peak is observed at 532 nm. The
efficiency of second harmonic generation depends on several
factors, such as non-centrosymmetricity, intensity of push–pull
dipole effects caused by ligands, donor–acceptor bonds in the
framework, interaction between the guest molecules embedded
in the structure and the functional groups of the ligands.78
A small second harmonic response in this case can be explained
by the partial absorption of the crystal due to the presence of guest
bpy molecules, as well as by a decrease in non-centrosymmetricity
upon crossing the zig-zag chain because the dipole moments of
the functional units are greatly reduced. Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 3.2
Ligands The resulting compound
{[Zn2(nica)2(bpy)1.5(H2O)]0.5(bpy)3H2O}n
was
obtained
by
hydrothermal synthesis and investigated by IR spectroscopy
to determine possible coordination modes of the ligand with
the metal ion. As a result, eight different coordination modes
were suggested. Single-crystal diffraction studies have shown that the result-
ing compound crystallized in the crystal class mm2 (point group
C2v),77 in the orthorhombic non-centrosymmetric space group
Fdd2. The N,O- and O,O-chelation of the ZnII ions by nica2
results in the formation of zig-zag channels along the c-axis. The modest SHG response in the present case can be attributed
partly to the partial cancellation of non-centrosymmetry between
the intercrossing zig-zag chains as the dipole moments are
cancelled out and partly to the absorption by the crystal in the
presence of bpy guest molecules. Strong hydrogen interaction of
the water molecules with the carboxyl group in nica2 occurs. Also, a strong CH p interaction (purple and blue dashed lines) Different structures were observed for compounds with
p-pyridine carboxylato or m-pyridine carboxylato ligands (Fig. 14).80
Although the difference is small, m-pyridine carboxylate led to the
formation of 2D structures, in contrast to p-pyridine carboxylate,
which gave 3D structures. This type of 2D structure is formed
when a metal center is coordinated by unsymmetric bifunc-
tional ligands.80 If conditions are favorable, the 2D grids may
form a non-centrosymmetric crystal.80 In addition, m-pyridine This journal is © The Royal Society of Chemistry 2016 5418 | Chem. Soc. Rev., 2016, 45, 5408--5431 rganic frameworks (MOFs) and coordination polymers (CPs) with second harmonic generation (SHG) properties
osition
Ligand
Space group
SHG
Ref. 3.2
Ligands (EtOH)3H2O]n
X = tetrakis[4-(carboxyphenyl)oxamethyl]methane acid
Cc
2.5 KDP
36
N3)2(H2O)2]n
L = trans-2,3-dihydro-2-(40-pyridyl)-3-(300-tetrazolyl-phenyl)benzo[e]indole
Aba2
80 urea
37
Me2)6[Cd5(bta)4]}n
Hbta = biphenyl-2,20,6,60-tetracarboxylic acid
C2/c
0.8 KDP
38
hy)(SA)]n
bphy = 1,2-bis(4-pyridyl)hydrazine, H2SA = succinic acid
I213
0.1 KDP
39
t)(atz)]n
Hatz = 5-amino-1H-tetrazol, Hcpt = 4-(4H-1,2,4-triazol-4-yl)benzoic acid
P212121
0.13 KDP
40
pydc)]n
pydc = pyridine-2,5-dicarboxylate
P21
80 SiO2
41
tc)(CH3COO)(C4H9NO)3]n
H3btc = 1,3,5-benzenetricarboxylic acid
P212121
5 KDP
42
2(LC4)3(EtOH)6]Cl}n
H2LC4 = 25,27-bis(hydroxycarbonylmethoxy)-26,28-dimethoxy-p-tert-butylcalix[4]arene
I213
B0.8 urea
43
o2(LC4)3(EtOH)6]Cl}n
H2LC4 = 25,27-bis(hydroxycarbonylmethoxy)-26,28-dimethoxy-p-tert-butylcalix[4]arene
I213
B1.0 urea
43
H7)4]3[Ga3(btc)4]}n
H3btc = 1,3,5-benzene tricarboxylic acid
R3c
15 SiO2
44
p)2Br2H2O]n
anp = 2-amino-5-nitropyridine
Pnn2
2.1 KDP
45
tart)(CH2OHCH2OH)(H2O)]Cl}n
L-H2tart = L-tartaric acid
P21
0.5 urea
46
tart)(CH2OHCH2OH)(H2O)]Cl}n
D-H2tart = D-tartaric acid
P21
0.5 urea
46
bimb)EtOHH2O]n
L = (R)-4-(4-(1-carboxyethoxy)phenoxy)-3-fluorobenzoic acid,
bimb = 4,4-bis(1H-imidazol-1-yl-methyl)biphenyl
P212121
0.3 urea
47
bimb)EtOHH2O]n
L = (R)-4-(4-(1-carboxyethoxy)phenoxy)-3-chlorobenzoic acid,
bimb = 4,4-bis(1H-imidazol-1-yl-methyl)biphenyl
P212121
0.3 urea
47
bimb)EtOHH2O]n
L = (R)-4-(4-(1-carboxyethoxy) phenoxy)-3-nitroaniline acid,
bimb = 4,4-bis(1H-imidazol-1-yl-methyl)biphenyl
P212121
0.3 urea
47
2O)(L)2(bpp)2H2O]n
H2L = 4,40-(phenylazanediyl)dibenzoic acid, bpp = 1,3-di(pyridin-4-yl)propane
P21
0.7 urea
48
H2O]n
HL = L-malic acid
P21
4.24 KDP
49
3(NO3)22NO32CH3CN]n
L = (1R,2R)-1,2-bis(4-(1,2,4-triazolyl))cyclohexane
P41212
0.9 KDP
50
H2H2O]n
L = (1R,2R)-1,2-bis(4-(1,2,4-triazolyl))cyclohexane
P3121
0.1 KDP
50
b)]n
H2tzb = 1H-tetrazolate-5-butyric acid
Pca21
0.5 KDP
51
a)(Hpyim)H2O]n
H2dba = 4,40-methylenedibenzoic acid, Hpyim = 2-(2-pyridyl)imidazole
Cc
0.8 urea
52
p)(H2O)3H2O]n
H3sip = 5-sulfoisophthalic acid
Ama2
4 KDP
53
mp)2]n
H2dcmp = 2,5-dicarboxy-1-methylpyridinium chloride
Fdd2
7 KDP
54
a)2]n
ima = 2-(1H-imidazole-1-yl)acetate
Cc
0.5 urea
55
Ph3)(L)](ClO4)}n
L = N,N-(2-pyridyl)(4-pyridylmethyl)amine
Cc
1.5 urea
56
pidc)(H2O)2H2O]n
H3pidc = 2-(pyridin-4-yl)-1H-imidazole-4,5-dicarboxylic acid
Pna21
1.5 KDP
57
pidc)]n
H3pidc = 2-(pyridin-4-yl)-1H-imidazole-4,5-dicarboxylaic acid
Cc
0.9 urea
58
-ptz)2]n
(S)-Hptz = 5-[(2S)-pyrrolidine-2-yl]-1H-tetrazole
P21
0.35 KDP
59
-ptz)2]n
(S)-Hptz = 5-[(2S)-pyrrolidine-2-yl]-1H-tetrazole
P21
0.40 KDP
59
2(4,40-bipy)2]n
H2L = (S)-()-1,10-binaphtho-2,20-diacetic acid, 4,40-bipy = 4,40-bipyridine
P1
0.17 KDP
60
biim-4)H2O]n
H2L = (S)-()-1,10-binaphtho-2,20-diacetic acid, biim-4 = 1,10-(1,4-butanediyl)bis(imidazole)
P43
0.08 KDP
60
3(btb)(H2O)2]n
H2L = (S)-()-1,10-binaphtho-2,20-diacetic acid, btb = 1,6-bis(1,2,4-triazol-1-yl)hexane
P21
0.10 KDP
60
3-bdc)(opy)]n
1,3-H2bdc = isophthalic acid, opy = 4,40-(oxybis(4,1-phenylene))dipyridine
P65
0.3 urea
61
(H2L)(MeOH)H2O]n
H2L = N,N0-bis(salicylidene)-1,2-cyclohexanediamine
Pna21
0.4 urea
62
(DMF)(H2O)3]n
H2L = 4,40-(9,9-dimethyl-9H-fluorene-2,7-diyl)dibenzoic acid
P21
0.4 urea
63
DMF)]n
H2L = 4,40-(9,9-dimethyl-9H-fluorene-2,7-diyl)dibenzoic acid
Aba2
0.8 urea
63
H2O)2solvent]n
H4L = tetrakis[4-(carboxyphenyl)oxamethyl]methane acid, solvent = DMA/H2O
Fdd2
3.6 KDP
64
a)(py)2H2O
H2bipa = 5-bromoisophthalic acid, py = pyridine
P212121
0.7 urea
65
(btc)(titmb)]n
titmb = 1,3,5-tris(1-imidazol-1-ylmethyl)-2,4,6-trimethylbenzene,
H3btc = 1,3,5-benzene-tricarboxylic acid
P212121
0.7 urea
66
Review Article
Chem Soc R
Open Access Article. 3.2
Ligands 10
Possible coordination modes of deprotonated 2-hydroxy-nicotinic
acid. Adapted from ref. 77 with permission from r 1996–2016 MDPI AG. Review Article
View Article Online e 1
(continued)
y
Composition
Ligand
Space group
SHG
Ref. [Zn3(btc)2(titmb)H2O]n
titmb = 1,3,5-tris(1-imidazol-1-ylmethyl)-2,4,6-trimethylbenzene, H3btc =
1,3,5-benzene-tricarboxylic acid
P21
0.8 urea
66
[Zn(paba)2H2O]n
Hpaba = p-aminobenzoic acid
P212121
1 KDP
67
[Zn(tzf)2]n
Htzf = 1H-tetrazole-5-formic acid
I%42d
1.1 KDP
68
[NaZn(acac)2(AcO)EtOH]n
acac = acetylacetonate
P212121
15 KDP
69
[Cd2(4,40-bipy)2(H2O)3(SO4)23H2O]n
4,40-bipy = 4,40-bipyridine
C2
0.27 KDP
70
[Ag4(dob)4(BF4)4]n
dob = 1,3-di(2-oxazolinyl)benzene
Cc
0.3 urea
71
[Zn(L)2]n
HL = 1,3-dithiole-2-tetrazole
I%42d
0.7 KDP
72
{[Ca(L)(H2O)2]Cl2}n
L = b-D-fructose
P21
0.466 KDP
73
{[Ca(L)2(H2O)2]Cl2H2O}n
L = b-D-fructose
C2
0.122 KDP
73
[Zn2(1,3-bdc)(ppa)2(H2O)]n
ppa = pipemidic acid, H2bdc = 1,3-benzenedicarboxylic acid
Cc
5.6 KDP
74
Chem Soc Rev
Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Chem Soc Rev Entry
Composition
Ligand
Space group
SHG
41
[Zn3(btc)2(titmb)H2O]n
titmb = 1,3,5-tris(1-imidazol-1-ylmethyl)-2,4,6-trimethylbenzene, H3btc =
1,3,5-benzene-tricarboxylic acid
P21
0.8
42
[Zn(paba)2H2O]n
Hpaba = p-aminobenzoic acid
P212121
1
43
[Zn(tzf)2]n
Htzf = 1H-tetrazole-5-formic acid
I%42d
1.1
44
[NaZn(acac)2(AcO)EtOH]n
acac = acetylacetonate
P212121
15
45
[Cd2(4,40-bipy)2(H2O)3(SO4)23H2O]n
4,40-bipy = 4,40-bipyridine
C2
0.27
46
[Ag4(dob)4(BF4)4]n
dob = 1,3-di(2-oxazolinyl)benzene
Cc
0.3
47
[Zn(L)2]n
HL = 1,3-dithiole-2-tetrazole
I%42d
0.7
48
{[Ca(L)(H2O)2]Cl2}n
L = b-D-fructose
P21
0.46
49
{[Ca(L)2(H2O)2]Cl2H2O}n
L = b-D-fructose
C2
0.12
50
[Zn2(1,3-bdc)(ppa)2(H2O)]n
ppa = pipemidic acid, H2bdc = 1,3-benzenedicarboxylic acid
Cc
5.6 Fig. 10
Possible coordination modes of deprotonated 2-hydroxy-nicotinic
acid. Adapted from ref. 77 with permission from r 1996–2016 MDPI AG. carboxylates have their own electronic asymmetry, which also
has a positive effect on the NLO properties. Crystals of [Cu(H2Me4BPZ)Br0.5H2O]n (H2Me4BPZ = 3,30,5,50-
tetramethyl-4,40-bipyrazole), obtained by the reaction of CuBr
and H2Me4BPZ under solvothermal conditions, not only demon-
strate a SHG value comparable to that of KDP,81 but also exhibit
ferroelectric properties. In this species, a 3D porous structure
is formed by connecting four adjacent binding ligands of
H2Me4BPZ (Fig. 15), which in turn are connected by serrated
channels of [CuBr].81 It is, however, important that the used compounds are stable
under the influence of laser radiation, in contrast to, for example,
coordination polymers,82 so that studying the second harmonic
generation is technically possible. 3.2
Ligands Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. View Article On Chem Soc Rev
View Article Online Chem Soc Rev
View Article Online View Article Online 39
40
41
42
43
43
44
45
46
46
47
47
47
48
49
50
50
51
52
53
54
55
56
57
58
59
59
60
60
60
61
62
63
63
64
65
66 Table 1
Metal–organic frameworks (MOFs) and coordination polymers (CPs) with second harmonic generation (SHG) properties
Entry
Composition
Ligand
1
[Zn2(X)(EtOH)3H2O]n
X = tetrakis[4-(carboxyphenyl)oxamethyl]methane acid
2
[Cd(L-N3)2(H2O)2]n
L = trans-2,3-dihydro-2-(40-pyridyl)-3-(300-tetrazolyl-phenyl)benzo[e]indole
3
{(NH2Me2)6[Cd5(bta)4]}n
Hbta = biphenyl-2,20,6,60-tetracarboxylic acid
4
[Cd(bphy)(SA)]n
bphy = 1,2-bis(4-pyridyl)hydrazine, H2SA = succinic acid
5
[Zn(cpt)(atz)]n
Hatz = 5-amino-1H-tetrazol, Hcpt = 4-(4H-1,2,4-triazol-4-yl)benzoic acid
6
[Bi2O2(pydc)]n
pydc = pyridine-2,5-dicarboxylate
7
[Mg2(btc)(CH3COO)(C4H9NO)3]n
H3btc = 1,3,5-benzenetricarboxylic acid
8
{[K3Co2(LC4)3(EtOH)6]Cl}n
H2LC4 = 25,27-bis(hydroxycarbonylmethoxy)-26,28-dimethoxy-p-tert-butylcalix[4]arene
9
{[Rb3Co2(LC4)3(EtOH)6]Cl}n
H2LC4 = 25,27-bis(hydroxycarbonylmethoxy)-26,28-dimethoxy-p-tert-butylcalix[4]arene
10
{[N(C3H7)4]3[Ga3(btc)4]}n
H3btc = 1,3,5-benzene tricarboxylic acid
11
[Cd(anp)2Br2H2O]n
anp = 2-amino-5-nitropyridine
12
{[Ce(L-tart)(CH2OHCH2OH)(H2O)]Cl}n
L-H2tart = L-tartaric acid
13
{[Ce(D-tart)(CH2OHCH2OH)(H2O)]Cl}n
D-H2tart = D-tartaric acid
14
[Co(L)(bimb)EtOHH2O]n
L = (R)-4-(4-(1-carboxyethoxy)phenoxy)-3-fluorobenzoic acid,
bimb = 4,4-bis(1H-imidazol-1-yl-methyl)biphenyl
15
[Co(L)(bimb)EtOHH2O]n
L = (R)-4-(4-(1-carboxyethoxy)phenoxy)-3-chlorobenzoic acid,
bimb = 4,4-bis(1H-imidazol-1-yl-methyl)biphenyl
16
[Co(L)(bimb)EtOHH2O]n
L = (R)-4-(4-(1-carboxyethoxy) phenoxy)-3-nitroaniline acid,
bimb = 4,4-bis(1H-imidazol-1-yl-methyl)biphenyl
17
[Ni2(H2O)(L)2(bpp)2H2O]n
H2L = 4,40-(phenylazanediyl)dibenzoic acid, bpp = 1,3-di(pyridin-4-yl)propane
18
[Cs(L)H2O]n
HL = L-malic acid
19
[Zn2(L)3(NO3)22NO32CH3CN]n
L = (1R,2R)-1,2-bis(4-(1,2,4-triazolyl))cyclohexane
20
[AgLOH2H2O]n
L = (1R,2R)-1,2-bis(4-(1,2,4-triazolyl))cyclohexane
21
[Zn(tzb)]n
H2tzb = 1H-tetrazolate-5-butyric acid
22
[Zn(dba)(Hpyim)H2O]n
H2dba = 4,40-methylenedibenzoic acid, Hpyim = 2-(2-pyridyl)imidazole
23
[Sr(Hsip)(H2O)3H2O]n
H3sip = 5-sulfoisophthalic acid
24
[Zn(dcmp)2]n
H2dcmp = 2,5-dicarboxy-1-methylpyridinium chloride
25
[Zn(ima)2]n
ima = 2-(1H-imidazole-1-yl)acetate
26
{[Cu(PPh3)(L)](ClO4)}n
L = N,N-(2-pyridyl)(4-pyridylmethyl)amine
27
[Mn(Hpidc)(H2O)2H2O]n
H3pidc = 2-(pyridin-4-yl)-1H-imidazole-4,5-dicarboxylic acid
28
[Ag2(Hpidc)]n
H3pidc = 2-(pyridin-4-yl)-1H-imidazole-4,5-dicarboxylaic acid
29
[Cd((S)-ptz)2]n
(S)-Hptz = 5-[(2S)-pyrrolidine-2-yl]-1H-tetrazole
30
[Zn((S)-ptz)2]n
(S)-Hptz = 5-[(2S)-pyrrolidine-2-yl]-1H-tetrazole
31
[Zn2(L)2(4,40-bipy)2]n
H2L = (S)-()-1,10-binaphtho-2,20-diacetic acid, 4,40-bipy = 4,40-bipyridine
32
[Zn(L)(biim-4)H2O]n
H2L = (S)-()-1,10-binaphtho-2,20-diacetic acid, biim-4 = 1,10-(1,4-butanediyl)bis(imidazole)
33
[Zn3(L)3(btb)(H2O)2]n
H2L = (S)-()-1,10-binaphtho-2,20-diacetic acid, btb = 1,6-bis(1,2,4-triazol-1-yl)hexane
34
[Cu(1,3-bdc)(opy)]n
1,3-H2bdc = isophthalic acid, opy = 4,40-(oxybis(4,1-phenylene))dipyridine
35
[LuCl3(H2L)(MeOH)H2O]n
H2L = N,N0-bis(salicylidene)-1,2-cyclohexanediamine
36
[Mg(L)(DMF)(H2O)3]n
H2L = 4,40-(9,9-dimethyl-9H-fluorene-2,7-diyl)dibenzoic acid
37
[Zn(L)(DMF)]n
H2L = 4,40-(9,9-dimethyl-9H-fluorene-2,7-diyl)dibenzoic acid
38
[Cd2L(H2O)2solvent]n
H4L = tetrakis[4-(carboxyphenyl)oxamethyl]methane acid, solvent = DMA/H2O
39
Zn(bipa)(py)2H2O
H2bipa = 5-bromoisophthalic acid, py = pyridine
40
[Zn2Cl(btc)(titmb)]n
titmb = 1,3,5-tris(1-imidazol-1-ylmethyl)-2,4,6-trimethylbenzene,
H3btc = 1,3,5-benzene-tricarboxylic acid Chem. Soc. Rev., 2016, 45, 5408--5431 | 5419 This journal is ©The Royal Society of Chemistry 2016 This journal is ©The Royal Society of Chemistry 2016 Fig. This journal is © The Royal Society of Chemistry 2016 3.2
Ligands For example, measurements of
the second harmonic generation effect failed for the non-
centrosymmetric thallium(I) coordination polymer [Tl4(adc)(ox)]n
(adc = acetylenedicarboxylate, ox = oxalate) (Fig. 16) since decom-
position by the laser beam occurred, releasing potentially toxic
thallium(I) compounds.82 ( )
p
Previously, an attempt was made to study how the introduc-
tion of another metal in the metal–organic framework structure
will affect the non-linear optical properties of the system. The
first work on heterometallic compounds was focused on Cd2+
and Li+ ions. It was shown that the addition of alkali and
alkaline earth metals to the framework could significantly
enhance the SHG.83 The first frameworks were synthesized
in the presence of LiNO3 or NH4NO3 under solvothermal
conditions.83 Substituted 1,3- or 1,4-benzenedicarboxylate were
employed in the synthesis of heterometallic compounds,
{(NH2Me2)[CdLi( p-bdc)2]3CH3OH}n (1), {(NH2Me2)2[{Cd( p-bdc)2}3-
(NHMe2)]}n
(2),
{(NH2Me2)[CdLi(m-bdc)2]}n
(3),
{(NH2Me2)-
[{Cd(OH-m-Hbdc)(OH-m-bdc)}3(DMF)3(CH3OH)3H2O]}n
(4),
[Cd1.5Li(5-tBu-m-bdc)2(DMF)2]n (5), {(NH2Me2)[CdLi(oba)2]}n
(6), {(NH2Me2)[CdLi(sdba)23DMF3CH3OH]}n (7), and {(NH2Me2)-
[Cd3(H2O)3(OH)(sdba)3]}n (8) (!p-H2bdc = 1,4-benzenedicarboxylic
acid, m-H2bdc = 1,3-benzenedicarboxylic acid, OH-m-H2bdc =
5-hydroxy-1,3-benzenedicarboxylic
acid,
5-tBu-m-H2bdc
=
tert-butyl-1,3-benzenedicarboxylic acid, H2oba = 4,40-oxybis-
(benzoic acid) and H2sdba = 4,40-sulfonyldibenzoic acid), using Ligand 5420 | Chem. Soc. Rev., 2016, 45, 5408--5431 This journal is © The Royal Society of Chemistry 2016 Chem Soc Rev
View Article Online View Article Online Fig. 11
(a) Formation of metal chains in {[Zn2(nica)2(bpy)1.5(H2O)]0.5(bpy)3H2O}n through coordination of nica2 (H2nica = nicotinic acid) ligands in a
chelating manner; (b) the 3D framework in {[Zn2(nica)2(bpy)1.5(H2O)]0.5(bpy)3H2O}n viewed along the c-axis; (c) incorporation of guest molecules such
as water and 4,40-bipyridine. Adapted from ref. 77 with permission from r 1996–2016 MDPI AG. Review Article
Chem Soc Rev
View Article Online Chem Soc Rev Review Article view Article ccess Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:1
This article is licensed under a Creative Commons Attribution 3.0 Unported Fig. 11
(a) Formation of metal chains in {[Zn2(nica)2(bpy)1.5(H2O)]0.5(bpy)3H2O}n through coordination of nica2 (H2nica = nicotinic acid) ligands in a
chelating manner; (b) the 3D framework in {[Zn2(nica)2(bpy)1.5(H2O)]0.5(bpy)3H2O}n viewed along the c-axis; (c) incorporation of guest molecules such
as water and 4,40-bipyridine. Adapted from ref. 77 with permission from r 1996–2016 MDPI AG. Fig. 3.2
Ligands 11
(a) Formation of metal chains in {[Zn2(nica)2(bpy)1.5(H2O)]0.5(bpy)3H2O}n through coordination of nica2 (H2nica = nicotinic acid) ligands in a
chelating manner; (b) the 3D framework in {[Zn2(nica)2(bpy)1.5(H2O)]0.5(bpy)3H2O}n viewed along the c-axis; (c) incorporation of guest molecules such
as water and 4,40-bipyridine. Adapted from ref. 77 with permission from r 1996–2016 MDPI AG. Fig. 11
(a) Formation of metal chains in {[Zn2(nica)2(bpy)1.5(H2O)]0.5(bpy)3H2O}n through coordination of nica2 (H2nica = nicotinic acid) ligands in a
chelating manner; (b) the 3D framework in {[Zn2(nica)2(bpy)1.5(H2O)]0.5(bpy)3H2O}n viewed along the c-axis; (c) incorporation of guest molecules such
as water and 4,40-bipyridine. Adapted from ref. 77 with permission from r 1996–2016 MDPI AG. Fig. 15
Part of the crystalline structure of [Cu(H2Me4BPZ)Br0.5H2O]n. Left: 1D serrated channels extending along the c-axis; right: side view of
the 3D framework. Adapted from ref. 81. Copyright r 2016 Elsevier B.V. Fig. 12
Section of the structure of [Zn2(pidc)(H2O)Cl]n.78 Fig. 12
Section of the structure of [Zn2(pidc)(H2O)Cl]n.78 Fig. 15
Part of the crystalline structure of [Cu(H2Me4BPZ)Br0.5H2O]n. Left: 1D serrated channels extending along the c-axis; right: side view of
the 3D framework. Adapted from ref. 81. Copyright r 2016 Elsevier B.V. Fig. 16
Schematic diagram for [Tl4(adc)(ox)]n in the [010] projection. Adapted from ref. 82. Copyright r 2016 Elsevier. Fig. 13
Section of the structure of [Mn(Hpidc)(H2O)2H2O]n.78 Fig. 13
Section of the structure of [Mn(Hpidc)(H2O)2H2O]n.78 Fig. 13
Section of the structure of [Mn(Hpidc)(H2O)2H2O]n.78 Fig. 16
Schematic diagram for [Tl4(adc)(ox)]n in the [010] projection. Adapted from ref. 82. Copyright r 2016 Elsevier. Compound 2 exhibited the lowest SHG value, which is none-
theless still about two times greater than quartz, due to the fact
that the shortest ligand with a lower degree of conjugation
was used. Compound 6 exhibited the highest value, namely
800 times greater than quartz, and has good prospects, since
its characteristics are better than that of technologically impor-
tant LiNbO3 (600 times greater SHG than that of quartz). Compound 2 exhibited the lowest SHG value, which is none-
theless still about two times greater than quartz, due to the fact
that the shortest ligand with a lower degree of conjugation
was used. Compound 6 exhibited the highest value, namely
800 times greater than quartz, and has good prospects, since
its characteristics are better than that of technologically impor-
tant LiNbO3 (600 times greater SHG than that of quartz). Fig. This journal is ©The Royal Society of Chemistry 2016 Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. A metal–organic framework based on a trinickel secondary
building unit was produced using a ligand with two chiral
centers, which simultaneously serve as the donor and the
acceptor in the system (Fig. 17). Such properties of a ligand
are necessary for the generation of non-linear optical proper-
ties. The cyano group can be converted to a tetrazole in a click
reaction with NaN3. The molecule with two chiral centers
(Fig. 17a), which has no symmetry, also crystallizes in a non-
centrosymmetric space group. The significant enhancement of
second harmonic generation was related to the cumulative
effect caused by a high degree of asymmetry of the ligand
due to the so-called pull–push effect and the metal–ligand
coordination.86 It follows from the above that non-centrosymmetric MOFs,
which can be obtained by employing aromatic chiral ligands or
asymmetric ligands with a pull–push effect (with an electron
donor–acceptor system), can replace the existing materials for
NLO, but the synthetic methods are complicated and chiral
ligands can be expensive. An alternative synthetic strategy is
so-called spontaneous resolution based on achiral ligands. Spontaneous resolution is the separation of racemates into
their enantiomers in the form of conglomerates, which is a
rare phenomenon. To obtain a non-centrosymmetric or chiral
porous material by spontaneous resolution, it is preferable
to use rigid achiral ligands with low symmetry. For example,
deprotonated pyridine-3,5-dicarboxylic acid (3,5-H2PDC) was
employed as a rigid V-shaped tridentate ligand with a lower
symmetry (C2v) compared to typical tridentate ligands of
deprotonated 1,3,5-benezetricarboxylic acid (D3d symmetry).88
One advantage of dianionic 3,5-PDC in the coordination of a
divalent metal is the formation of neutral compounds.88 Coordination
polymers
[Zn(bindc)Cl2]n,
[Zn(bindc)Br2]n
and [Ag(bindc)NO3]n (bindc = N,N0-bis(isonicotinoyl)-(1R,2R)-
diaminocyclohexane) forming a helical superstructure, which
is known to result in considerable enhancement of second
harmonic generation, were constructed from the C2-symmetrical
chiral N,N0-bis(isonicotinoyl)-(1R,2R)-diaminocyclohexane (bindc)
and ZnII, AgI and CuI via complementary hydrogen interactions
of the bis(amido) ligands.87 To ensure the formation of a highly
dimensional structure, ligands containing amide groups were
selected, because these groups provide strong hydrogen inter-
actions with predictable regularity, which is particularly useful
for self-assembly processes.87 It was shown that the solvent plays a key role in the
preparation of metal–organic frameworks influencing the final
structure. Using spontaneous resolution under solvothermal
conditions and solvents such as DMF and ethylene glycol, a
chiral MOF, [Mn(3,5-PDC)(H2O)(glycol)]n with helical channels
(Fig. This journal is © The Royal Society of Chemistry 2016 3.2
Ligands 14
Synthesis of 2D coordination polymers consisting of d10 metals
and bridging p-pyridine carboxylato ligands. Adopted from ref. 80. Fig. 14
Synthesis of 2D coordination polymers consisting of d10 metals
and bridging p-pyridine carboxylato ligands. Adopted from ref. 80. the solvothermal method.83 Six compounds (2, 3, 4, 6, 7, and 8)
were also investigated qualitatively based on the fact that they all
crystallize in acentric (3) or chiral space groups (2, 4, 6, 7, and 8). Chem. Soc. Rev., 2016, 45, 5408--5431 | 5421 This journal is ©The Royal Society of Chemistry 2016 View Article Online View Article Online Chem Soc Rev Review Article Review Article The exceptions to the series are 1 and 5, since they crystallize
in centrosymmetric structures. to the helical superstructure in bindc. This is not observed in
coordination polymers or MOFs, where the pyridyl nitrogen
atom is involved in the coordination to metal ions.87 However, the use of the proposed strategy83 was not successful
in other cases; for example, [CdCa(m-bdc)2(DMF)2]n, [CdCa(OH-m-
bdc)2(H2O)22NHMe2]n, and [CdSr2(m-bdc)2(NO3)2(DMF)4]n show
weak SHG values, despite crystallizing in non-centrosymmetric
structures.84 The zinc complex [Zn(bindc)Cl2]n has a tetrahedral coordi-
nation, including two chloro ligands and two nitrogen atoms of
two different bindc molecules. Coordinated dipyridyl of the
ligand molecules forms an extended one-dimensional channel
along the b-axis, complementary amide hydrogen bonds form
one-dimensional zig-zag chains ‘‘parallel’’ to one another along
the crystallographic c-axis, and the chloro ligands approach
the pyridyl hydrogen atoms along the a-axis, resulting in a
three-dimensional network. The replacement of zinc(II) with
other metal(II) ions does not lead to significant changes in the
second harmonic generation, but affects the thermal stability of
the material.87 3.2.2
Chiral ligands. It should first be noted that all chiral
MOFs are active for SHG,85 and there are some basic synthetic
approaches to produce a chiral MOF. However, one should bear in
mind that the presence of a chiral structure does not necessarily
guarantee a high response of second harmonic generation. Perhaps
this is one of the reasons why researchers are on an alternative
path to produce non-centrosymmetric structures. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 3.3
Diamondoid structures The most likely candidates for producing crystals with non-linear
optical properties are metal ions, which have a coordination
number of 4 or 8 and are connected via a bifunctional ligand. Such components tend to form the so-called diamond structure
(Fig. 20).89,91,93 According to several studies, diamondoid struc-
tures are defined as promising in terms of obtaining non-
centrosymmetric structures. Crystals of diamond-type inherently
crystallize in a centrosymmetric space group (Fd3m), so that the
inversion center is in the middle of the C–C bond between two
adjacent nodes. To obtain non-centrosymmetric structures, non-
centrosymmetric bridging ligands and different adjacent con-
necting nodes (Fig. 21) can be used.80 Assuming a diamondoid
topology with an Si–O–Si bond angle of 1441, one can produce
V-shaped bonds between two adjacent Si atoms, which generally
results in non-centrosymmetric structures (Fig. 22). Fig. 18
(a)
The
Mn–O–C
chain
along
the
61
axis
connected
to
each other to form the chiral JUC-58 framework and (b) the network of
JUC-58 looking down the 61 axis (001 direction), showing the homochiral
water chain included in the channels. Adapted from ref. 88 (Copyright r
2013 Elsevier). harmonic values. It is interesting to note that simply immersing
the obtained product in another solvent does not result in
structural changes.89 Another interesting case is a series of pillared-layer metal–organic
frameworks [Cd(5-aip)(bpy)1.5DMA]n, [Cu(5-aip)(bpy)1.3DMA]n,
[Co(5-aip)(bpy)1.6DMA]n, and [Cd(5-aip)(bpy)0.5(H2O)1.3DMA]n
derived from 5-aminoisophthalic acid (Haip), 4,40-bipyridine (bpy)
and MII. A symmetry change from chiral to achiral occurs by
soaking the crystals in methanol at room temperature. This fact is
explained by a change in the torsion angle of the aromatic rings of
the bipyridine ligands after substitution of DMA molecules in the
channels with methanol.90 The diamondoid structure can be adjusted by changing
the length of the ligand in the system. Thus, changing the
length of the p-pyridine carboxylato ligand in Zn2+- or Cd2+-
based two-dimensional coordination polymers resulted in non-
centrosymmetric
diamondoid
structures
which
showed
a Fig. 20
Topological view of the structural transformation from the chiral
dia net to the achiral dia net. Adapted from ref. 89 (r Royal Society of
Chemistry 2016). Strategies for potentially adjusting the symmetry of crystals
have been reported.91 However, one should always consider the
solvent effect to control changes in lattice parameters with a
change in crystal symmetry, which may affect the mechanical
properties of the material. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 18), and two isostructural non-centrosymmetric MOFs,
[M(3,5-PDC)(H2O)(glycol)H2O]n (M = Co, Ni), were synthesized. Unfortunately, measuring second harmonic generation was outside
the scope of this study.88 However, this work demonstrates a
new synthetic route for so-called spontaneous resolution,
which turned out to be perfectly suited for the preparation of
chiral and non-centrosymmetric MOFs. Measurements using the Kurtz–Perry method yielded values
of 0.8 U (1 U = SHG of urea) for bindc, even though this
molecule does not have strong pull–push effects. This is due Fig. 17
(a) Ligand reported by Xiong et al.; (b) the corresponding in situ
generated ligand; and (c) schematic illustration of a donor–acceptor
system. Adapted from ref. 86 (Copyright r 2005, American Chemical
Society). It was also shown that even weak interactions between guest
molecules and the framework can cause a transition from a
chiral to an achiral structure depending on the size of the guest
species. One example is Zn(ain)2 (Hain = 2-aminoisonicotinic
acid) in which a transition from a chiral to an achiral crystal was
observed depending on the solvent used in the synthesis (DMA or
DMF). The compounds [Zn(ain)2(DMA)]n and [Zn(ain)2(DMF)]n
have the same structural network, but slightly different crystal
symmetries, and their channels have a different shape,89 due to
the different sizes of DMA and DMF.89 Such seemingly small
differences can lead to a probable variation of the second Fig. 17
(a) Ligand reported by Xiong et al.; (b) the corresponding in situ
generated ligand; and (c) schematic illustration of a donor–acceptor
system. Adapted from ref. 86 (Copyright r 2005, American Chemical
Society). Fig. 17
(a) Ligand reported by Xiong et al.; (b) the corresponding in situ
generated ligand; and (c) schematic illustration of a donor–acceptor
system. Adapted from ref. 86 (Copyright r 2005, American Chemical
Society). 5422 | Chem. Soc. Rev., 2016, 45, 5408--5431 5422 | Chem. Soc. Rev., 2016, 45, 5408--5431 This journal is © The Royal Society of Chemistry 2016 Fig. 18
(a)
The
Mn–O–C
chain
along
the
61
axis
connected
to
each other to form the chiral JUC-58 framework and (b) the network of
JUC-58 looking down the 61 axis (001 direction), showing the homochiral
water chain included in the channels. Adapted from ref. 88 (Copyright r
2013 Elsevier). Review Article
Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. icle is licensed under a Creative Commons Attribution 3.0 Unported Licence. Review Article Review Article Review Article Fig. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 19
A simplified 3D diamond-like structure of Cd(Imazethapyr)2. Straight lines resemble ligands, balls correspond to metal ions. Adapted
from ref. 92 (Copyright r 2002, American Chemical Society). Fig. 19
A simplified 3D diamond-like structure of Cd(Imazethapyr)2. Straight lines resemble ligands, balls correspond to metal ions. Adapted
from ref. 92 (Copyright r 2002, American Chemical Society). adjacent cadmium ions. The second harmonic generation value
for Cd(Imazethapyr)2 is 20 times higher than that of potassium
dihydrogen phosphate. This journal is ©The Royal Society of Chemistry 2016 Chem. Soc. Rev., 2016, 45, 5408--5431 | 5423 3.3
Diamondoid structures This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Fig. 21
Two methods for removing an inversion center in a diamondoid
structure: (top) using unsymmetrical linkage and (below) using different
adjacent nodes. Adapted from ref. 80 (Copyright r 2012, American
Chemical Society). higher SHG with a systematic increase in the length of the
ligand,93–95 i.e. with increasing conjugation between the donor
and the acceptor, which in turn increases hyperpolarizability
of the chromophores. Here, it is shown for the first time that
non-linear optical properties can be changed by changing the
length of the bridging conjugated ligands. For example, the
obtained materials exhibit an SHG intensity of up to 400 times
that of a-quartz.92 Tetrazoles can act as bridging ligands for d10 metal ions96–98
yielding a tetrahedral coordination, which enables a diamondoid
structure to form 1H-tetrazolate-5-butyrate coordination polymers,
[Zn(tzb)]n and [Zn(3-ptz)2]n (H2tzb = 1H-tetrazolate-5-butyric acid,
3-ptz = 5-(3-pyridyl)tetrazolate). There are no interpenetrations in
the network of the resulting compound, [Zn(3-ptz)2]n, which was
obtained by hydrothermal synthesis, due to the short distance
between the metal ions and large substituents on the tetrazole. Fig. 23
Representation
of
the
non-centrosymmetric
structure
of
[C(NH2)3]2[TiF6]; (a) in the ab plane; and (b) showing the F H bonds. Adopted from ref. 110 (Copyright r 2011 Elsevier Inc). 3.3
Diamondoid structures Also, substitution conditions must be
chosen which ensure that the process proceeds to completion. Also, apart from using asymmetric ligands, there is a strategy of
using racemates. One example is diamond-like [Cd(Imazethapyr)2]n
which crystallizes in a non-centrosymmetric space group (Fdd2)
belonging to a polar point group (C2v). This metal–organic frame-
work is obtained by the reaction of racemic H-Imazethapyr with
Cd(ClO4)26H2O under hydrothermal conditions (Fig. 19).92
There are no network interpenetrations in the final structure
due to steric constraints and short distances between two Fig. 20
Topological view of the structural transformation from the chiral
dia net to the achiral dia net. Adapted from ref. 89 (r Royal Society of
Chemistry 2016). Chem. Soc. Rev., 2016, 45, 5408--5431 | 5423 View Article Online Chem Soc Rev Review Article Review Article Fig. 21
Two methods for removing an inversion center in a diamondoid
structure: (top) using unsymmetrical linkage and (below) using different
adjacent nodes. Adapted from ref. 80 (Copyright r 2012, American
Chemical Society). distribution of the electron density may increase the overall
energy of
the system. Accordingly,
elongation of
bonds
along the z-axis occurs, resulting in a lower symmetry.101–109
Unfortunately, such an approach cannot warrant the expected
result; therefore, the main task is controlling the macroscopic
symmetry of the system.110 In the crystallization of a material, its symmetry may be
affected not only by the selected cation, but also by its environ-
ment arising from the interaction of hydrogen bonds.110
To determine the influence of hydrogen bonding on the orien-
tation of the structure, two compounds were chosen: centro-
symmetric
[NMe4]2[TiF6]
and
polar
non-centrosymmetric
[C(NH2)3]2[TiF6] (Fig. 23). With regards to non-linear optical
properties, a value 25 times higher than that of SiO2 was
obtained. The compounds under consideration have the same
type of structure, the zero-dimensional TiF6 octahedra and
organic cations, but they crystallize with different symmetries. In the case of [C(NH2)3]2[TiF6], the alignment of the distorted
octahedra is mainly responsible for the polar crystal structure
and second harmonic generation, respectively. The eccentric
distortion of the TiF6 octahedra is due to the interaction of
hydrogen bonds between fluoride in the [TiF6]2 octahedra and
the H–N bonds of the [C(NH2)3]+ cation, which are the key
factor in determining the polar structure upon aligning the
TiF6 octahedra. In contrast, interactions between the hydrogen Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. 5424 | Chem. Soc. Rev., 2016, 45, 5408--5431 This journal is © The Royal Society of Chemistry 2016 3.4
Zero-dimensional objects As was shown in several studies,99,100 cations with octahedral
coordination, distorted by second-order Jahn–Teller effects,
such as high-spin d4 (e.g., CrF2), low-spin d7 (e.g., NaNiO2),
and d9 (e.g., Cu2+), are quite an important factor for non-
centrosymmetricity of the structure. In the case of octahedral
d9 configuration, the unpaired electron may occupy either the
dz2 or dx2y2 orbital of the eg set. If it occupies the dz2 orbital,
most of the electron density will be concentrated between the
metal and the two ligands on the z-axis. Thus, there will be
greater electrostatic repulsion associated with these ligands
than with the other four in the xy plane. This asymmetric Fig. 22
An illustrative example for a-quartz. Adapted from ref. 80 (Copyright r
2012, American Chemical Society). Fig. 23
Representation
of
the
non-centrosymmetric
structure
of
[C(NH2)3]2[TiF6]; (a) in the ab plane; and (b) showing the F H bonds. Adopted from ref. 110 (Copyright r 2011 Elsevier Inc). Fig. 22
An illustrative example for a-quartz. Adapted from ref. 80 (Copyright r
2012, American Chemical Society). 5424 | Chem. Soc. Rev., 2016, 45, 5408--5431 5424 | Chem. Soc. Rev., 2016, 45, 5408--5431 This journal is © The Royal Society of Chemistry 2016 This journal is © The Royal Society of Chemistry 2016 Fig. 25
Left: Schematic representation of the cationic building block for
the octupolar structure of {[Cd3(m3-OH)((E)-4-pyv-4-bza)3(py)6](ClO4)2}n. Right: Schematic representation of the 2D octupolar structure. Adapted
from ref. 112. Copyright r 1999, American Chemical Society. Chem Soc Rev
View Article Online View Article Online Review Article atoms in [NMe4]+ and fluoride in [TiF6]2 in [NMe4]2[TiF6] are
extremely weak. The effect achieved in this case is incompar-
ably smaller than strong hydrogen interactions present in
[C(NH2)3]2[TiF6]. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Fig. 25
Left: Schematic representation of the cationic building block for
the octupolar structure of {[Cd3(m3-OH)((E)-4-pyv-4-bza)3(py)6](ClO4)2}n. Right: Schematic representation of the 2D octupolar structure. Adapted
from ref. 112. Copyright r 1999, American Chemical Society. Fig. 25
Left: Schematic representation of the cationic building block for
the octupolar structure of {[Cd3(m3-OH)((E)-4-pyv-4-bza)3(py)6](ClO4)2}n. Right: Schematic representation of the 2D octupolar structure. Adapted
from ref. 112. Copyright r 1999, American Chemical Society. Fig. 26
Left: Representation of the 3D anionic network of {(NH2Me2)2-
[Cd3(C2O4)4]MeOH2H2O}n; right: representation of the hexanuclear
octupolar structure of [Cd6(C2O4)8]4. Adapted from ref. 113 (Copyright r
2007 John Wiley & Sons). Fig. 26
Left: Representation of the 3D anionic network of {(NH2Me2)2-
[Cd3(C2O4)4]MeOH2H2O}n; right: representation of the hexanuclear
octupolar structure of [Cd6(C2O4)8]4. Adapted from ref. 113 (Copyright r
2007 John Wiley & Sons). With regards to MOFs, in order to obtain non-centrosymmetric
octupolar structures with non-linear optical properties, trinuclear
metal clusters can be used as building units. One example
is {[Cd3(m3-OH)((E)-4-pyv-4-bza)3(py)6](ClO4)2}n ((E)-4-pyv-4-bza =
4-[2-(4-pyridyl)ethenyl]benzoate) obtained from Cd(ClO4)26H2O
and ethyl 4-[2-(4-pyridyl)ethenyl]benzoate using the hydro/
solvothermal method.112 Cadmium carboxylates, acting as
secondary building blocks, give rise to a symmetry with 3-fold
rotational symmetry (octupolar chromophores). The result is a
chiral two-dimensional structure (Fig. 25). The measured signal
of second harmonic generation has 130 times greater intensity
than that of a-quartz.112 network with a rare, crystallographically imposed Td symmetry. In such a system, there are small voids which are occupied by
(NH2Me2)+ cations and solvent molecules (MeOH and H2O). The
complete replacement of NH2Me2
+ in {(NH2Me2)2[Cd3(C2O4)4]
MeOH2H2O}n by NH4
+, K+, or Na+ was accomplished and
increases the resulting response to 155-, 110-, and 90-times that
of a-quartz, respectively. It appears that a decrease in the radius
of the ion, which is exchanged, results in a decrease in the
second harmonic generation response.113 3.5
Octupolar MOFs Molecules possessing octupolar symmetry have long been the
focus of investigations of non-linear optical properties. While
dipoles
tend
to
centrosymmetric
organization,
molecules
with octupolar symmetry tend to form non-centrosymmetric
structures.111 It has been successfully demonstrated previously
that a number of individual molecules with octupolar sym-
metry yield high second harmonic generation.111 An example of
a system with octupolar symmetry is an octupole consisting of
charges in the corners of a cube, where positive charges are
located at positions (1,0,0), (0,1,0), (0,0,1) and (1,1,1), and
negative charges at points (0,0,0), (1,1,0), (1,0,1) and (0,1,1).111
In organic chemistry, an example of an octupolar molecule is a
benzene ring, in which electron donors and acceptors alternate
(Fig. 24).111 Such a molecule has high non-linear optical proper-
ties and does not have a permanent dipole moment, avoiding
probable centrosymmetric crystallization.111 Typical examples
are molecules with a C3 symmetry axis, since it was shown that
among the molecules with Cn symmetry axes, only molecules
with a C3 axis do not have a dipole moment, but possess a finite
hyperpolarizability component.111 Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 3.7
1D coordination polymers: formation of channels Obtaining non-centrosymmetric structures with 1D channels may
be interesting even despite the fact that it is virtually impossible to
control the structure in the other two dimensions. The first data
on a 1D coordination polymer with non-linear optical properties
were reported for cadmium chalcogenocyanates.118 Anionic
[Cd(XCN)3] (X = S or Se) polymeric chains may assume a non-
centrosymmetric structure with all chalcogen atoms in the trans
position to the nitrogen atoms (due to the trans effect) (Fig. 31). The formation of a non-centrosymmetric structure is strongly
dependent on the symmetry of the cation. A compound with
a crown-ether–metal cation with a center of inversion crystal-
lizes in a centrosymmetric space group, while the monocation
[K(18-crown-6)]+, which lacks a center of inversion, leads to the
formation of a non-centrosymmetric material. The observed
second harmonic generation in [K(18-crown-6)][Cd(XCN)3] is
15 times higher than that of quartz. Fig. 27
Illustration of the maximum degree of interpenetration for
degree 5. Adopted from ref. 114 with permission from r 1999–2016 John
Wiley & Sons, Inc. Fig. 28
Illustration of the maximum degree of interpenetration for
degree 7. Adopted from ref. 117 with permission from r 2016 American
Chemical Society. Fig. 29
Illustration of the maximum degree of interpenetration (for
degree 8). Adopted from ref. 116 with permission from r Royal Society
of Chemistry 2016. Fig. 30
3D MOFs of diamondoid topology built from tetrahedrally
coordinated Zn2+ or Cd2+ and p-pyridine carboxylate linkers. Adopted
from ref. 117. Copyright r 2016 American Chemical Society. ccess Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Fig. 27
Illustration of the maximum degree of interpenetration for
degree 5. Adopted from ref. 114 with permission from r 1999–2016 John
Wiley & Sons, Inc. Fig. 27
Illustration of the maximum degree of interpenetration for
degree 5. Adopted from ref. 114 with permission from r 1999–2016 John
Wiley & Sons, Inc. Fig. 28
Illustration of the maximum degree of interpenetration for
degree 7. Adopted from ref. 117 with permission from r 2016 American
Chemical Society. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:1
This article is licensed under a Creative Commons Attribution 3.0 Unported It is, however, also necessary to take into account the mutual
orientation of the channels with respect to each other. 3.7
1D coordination polymers: formation of channels For
example, the compound [Co(pydc)(H2O)2]nnH2O (pydc = pyridine-
3,4-dicarboxylate) yields only a subtle response due to the fact
that the channels are oriented antiparallel to each other, which
nullifies the dipole moment, thus preventing possible second
harmonic generation.119 Fig. 28
Illustration of the maximum degree of interpenetration for
degree 7. Adopted from ref. 117 with permission from r 2016 American
Chemical Society. Fig. 28
Illustration of the maximum degree of interpenetration for
degree 7. Adopted from ref. 117 with permission from r 2016 American
Chemical Society. Creating a structure with some self-blockage may be of
interest as well. In [Zn(pydc)]n, three Zn2+ cations are connected
by 4-[2-(4-pyridyl)ethenyl]cinnamate ligands, resulting in the
formation of zig-zag channels. Parallel channels are connected
by p–p interactions.120 4. New applications of MOFs in
non-linear optics: prospects Fig. 29
Illustration of the maximum degree of interpenetration (for
degree 8). Adopted from ref. 116 with permission from r Royal Society
of Chemistry 2016. Fig. 29
Illustration of the maximum degree of interpenetration (for
degree 8). Adopted from ref. 116 with permission from r Royal Society
of Chemistry 2016. Fig. 29
Illustration of the maximum degree of interpenetration (for
degree 8). Adopted from ref. 116 with permission from r Royal Society
of Chemistry 2016. 3.6
Effect of the degree of interpenetration of grids 27
Illustration of the maximum degree of interpenetration for
degree 5. Adopted from ref. 114 with permission from r 1999–2016 John
Wiley & Sons, Inc. Chem Soc Rev Fig. 27
Illustration of the maximum degree of interpenetration for
degree 5. Adopted from ref. 114 with permission from r 1999–2016 John
Wiley & Sons, Inc. Chem Soc Rev Chem Soc Rev Chem Soc Rev 3.6
Effect of the degree of interpenetration of grids Another example from this area is {(NH2Me2)2[Cd3(C2O4)4]
MeOH2H2O}n, a MOF synthesized solvothermally from CdCO3
and oxalic acid.113 This compound forms a three-dimensional
porous network with a cubic acentric space group (Fig. 26). The
unit in this case is two sets of equilateral triangles [Cd3(C2O4)4]2
as a structural motif whose center lies on the threefold axis of
rotation forming a hexameric [Cd6(C2O4)8]4 ionic cluster.113
Their interaction leads to an octupolar, 3D anionic supercage Second harmonic generation is strongly influenced by the degree
of interpenetration of grids.114–117 Interpenetration can occur
when large voids are formed in a diamondoid crystal by extended
ligands. Examples are the structures of [Zn(4-pya)]n and
[Cd(4-pya)2H2O]n, [where 4-pya = (E)-3-(pyridin-4-yl)acrylate], which
yield 5-fold interpenetration (Fig. 27) and crystallize in non-
centrosymmetric space groups.114 When using a ligand such as
4-(4-pyridyl)benzoate, the degree of interpenetration can be
increased up to 7 (Fig. 28) in [Cd{4-(4-pyridyl)benzoate}2H2O]n,117
and for 4-[2-(4-pyridyl)ethenyl]benzoate, which contains an
additional ethylene group, even up to 8 (Fig. 29) in [Cd(4-{2-
(4-pyridyl)ethenyl}-benzoate)2]n.114 Crystallization in a chiral
space group is also possible in cases when the degree of
interpenetration is even, for example 10.114,115 Fig. 24
An octupolar molecule with acceptors and donors alternating
around a benzene ring. Unsymmetric ligands for achieving an unsymmetric distri-
bution of electrons and eliminating the inversion center for
MOFs with tetrahedrally coordinated metal centers (Fig. 30) Fig. 24
An octupolar molecule with acceptors and donors alternating
around a benzene ring. Fig. 24
An octupolar molecule with acceptors and donors alternating
around a benzene ring. Chem. Soc. Rev., 2016, 45, 5408--5431 | 5425 This journal is ©The Royal Society of Chemistry 2016 This journal is ©The Royal Society of Chemistry 2016 Review Article
View Article Online Review Article
View Article Online Fig. 27
Illustration of the maximum degree of interpenetration for
degree 5. Adopted from ref. 114 with permission from r 1999–2016 John
Wiley & Sons, Inc. Fig. 28
Illustration of the maximum degree of interpenetration for
degree 7. Adopted from ref. 117 with permission from r 2016 American
Chemical Society. Fig. 29
Illustration of the maximum degree of interpenetration (for
degree 8). Adopted from ref. 116 with permission from r Royal Society
of Chemistry 2016. Chem Soc Rev
Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. View Article Online View Article Online Fig. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. In conclusion, in the production of NLO materials and even
non-linear and quantum metamaterials, special attention
should be paid to the class of metal–organic frameworks that
combine the properties of organic and inorganic constituents. Particular attention should be paid to the selection of the
metal–ligand pair. In order to further improve the optical
properties of the produced materials, different parameters such
as the length of the ligand, the degree of its substitution, the
conjugation in the system, and the use of guest molecules with
different natures should be adjusted. It should, however, be
noted that the parameters of an obtained MOF crystal can be
significantly affected by minor external influences, such as
replacing solvent molecules with a different type of guest
molecule, which in turn may lead to a change in the symmetry
of the system. One should additionally take into account the
fact that the best control in terms of prediction is provided for
3D structures, while 2D or 1D structures cannot be subjected to
similar control of their architectures. It is also possible to
change the degree of interpenetration of networks, which
greatly affects the non-linear optical properties of the material. As proof-of-principle, a layered metal–organic framework
[{Zn2(tbapy)(H2O)2}3.5DEF]n (tbapy = 1,3,6,8-tetrakis( p-benzoate)-
pyrene) was studied by Vinogradov, Hey-Hawkins et al.124 The
obtained adsorption, reflection and photoluminescence spectra
indicate the presence of at least two types of excitons (Fig. 32). Since the compound has a layered structure, which limits the
exciton motion in the same direction, they are divided into intra-
layer, electrons and holes existing in the same layer, and inter-
layer ones, located in different layers, respectively. While many efforts are being made to design MOF archi-
tectures that exhibit the desired properties, the possibility of
studying the material structure at the molecular level and the
measurement of its non-linear optical characteristics without
destruction of the material remains an area with fairly signifi-
cant problems. Fig. 32
The manifestation of excitons in optical spectra. (a) Absorption,
reflection and photoluminescence spectra of single crystals of [{Zn2(tbapy)-
(H2O)2}3.5DEF]n placed on a quartz substrate in air. A single crystal is
excited by continuous white light (100 mW cm2) to obtain absorption
and reflection spectra, and by pulsed UV light (6 ps, 60 MHz, 3.1 eV,
28 W cm2) to generate the photoluminescence. Peak/valley in absorption/
reflection spectra near the fundamental absorption (3.4 eV) is addressed to
exciton states. 4.2
Control of excitons The crystalline and organic nature of MOFs allows the existence of
Coulomb-bound electron–hole pairs (excitons). The potential
offered by manipulating excitons when exposed to light and
electric field is the basis for modern exciton transistors and
polariton lasers. Semiconductors or special two-dimensional
structures were typically used in such devices. Despite the fact
that extremely fast and highly efficient manipulation of excitons
can be obtained for such materials, there are limitations in the
operating temperatures and device architectures. Given these
shortcomings, an alternative is the use of ordered organic semi-
conductor structures which promote a shift of the operating
temperature, additionally reducing the rate of exciton recombina-
tion. With regards to the problem of a short life cycle the solution
is to use layered anisotropic materials. Taking into account the
facts outlined above, it can be concluded that the combination of
organic nature and crystal anisotropy is an effective solution for
studying exciton control at ambient temperatures. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 4.1
Third-order NLO A new trend is the study of non-linear optical properties of third
order for MOFs, which in turn has promise for use in all-optical
switching in waveguides.121 For example, crystals of [Cu3(L)23nH2O]n
and [CuAg2(HL)2]n (H3L = chelidamic acid) have the values
1.67 1033 and 1.52 1030 ESU,122 which are comparable Fig. 31
Schematic representation of (a) centrosymmetric and (b) non-
centrosymmetric channels of {[Cd(SCN)3]}n. Adapted from ref. 118. Copy-
right r 2016 Elsevier B.V. Fig. 30
3D MOFs of diamondoid topology built from tetrahedrally
coordinated Zn2+ or Cd2+ and p-pyridine carboxylate linkers. Adopted
from ref. 117. Copyright r 2016 American Chemical Society. were first employed in 1999.117 The degree of interpenetration
may be significantly increased by increasing the length of the
ligands, which promotes structures with more voluminous
cavities. Since an extended ligand improves the interface
between the donor and the acceptor, this in turn increases
the molecular hyperpolarizability of the chromophores, which
can improve the SHG of the crystal.8,11 Fig. 31
Schematic representation of (a) centrosymmetric and (b) non-
centrosymmetric channels of {[Cd(SCN)3]}n. Adapted from ref. 118. Copy-
right r 2016 Elsevier B.V. This journal is © The Royal Society of Chemistry 2016 5426 | Chem. Soc. Rev., 2016, 45, 5408--5431 Chem Soc Rev
View Article Online View Article Online View Article Online Review Article Chem Soc Rev to or even greater than the traditionally used crystals.123
Thus, MOFs reveal themselves as promising materials in this
field of third order non-linear effects. The study also demonstrated the efficient and independent
control of excitons via disordering the structure or photoexcitation
caused by light, which allows for achieving significant changes in
the optical properties of single crystals. The said changes can
either exist for a very short time or persist for several days. Thus,
this material is promising for use in various excitonic devices. This journal is ©The Royal Society of Chemistry 2016 Chem. Soc. Rev., 2016, 45, 5408--5431 | 5427 List of abbreviations Published on 20 September 2016. Downloaded on 10/24/2024 6:2
This article is licensed under a Creative Commons Attribution 3.0 Unpo Acknowledgements The authors are grateful to David Avnir for comprehensive
support of the SCAMT lab and scientific advices. We gratefully
acknowledge financial support from Leipzig University, the
German Academic Exchange Service (DAAD, postdoctoral grant
for A. V. V.), the ERASMUS + mobility program (A. V. V., L. M.,
E. H.-H.), the Russian Government Ministry of Education (this
research was made possible due to funds provided aiming at
maximising ITMO University’s competitive advantage among
world’s leading educational centres), the Russian Foundation for
Basic Research (grant no. 16-37-60073 mol_a_dk) and the EU COST
Action CM1302 Smart Inorganic Polymers (SIPs). The authors thank
Mr. Evgeny Uslamin (Eindhoven University of Technology) and
Mr. Aleksandr V. Yakovlev (ITMO University, Saint Petersburg) for
their help with the preparation of graphical material. List of abbreviations adc
Acetylenedicarboxylate
anp
2-Amino-5-nitropyridine
BBO
Barium borate, b-BaB2O4
4,40-bipy
4,40-Bipyridine
bimb
4,4-Bis(1H-imidazol-1-yl-methyl)biphenyl
bindc
N,N0-Bis(isonicotinoyl)-(1R,2R)-
diaminocyclohexane
biim-4
1,10-(1,4-Butanediyl)bis(imidazole)
bpp
1,3-Di(pyridin-4-yl)propane
bphy
1,2-Bis(4-pyridyl)hydrazine
btb
1,6-Bis(1,2,4-triazol-1-yl)hexane
CP
Coordination polymers
dcmp
2,5-Dicarboxy-1-methylpyridinium
dob
1,3-Di(2-oxazolinyl)benzene
Hacac
Acetyl acetone
Hain
2-Aminoisonicotinic acid
Haip
5-Aminoisophthalic acid
Hatz
5-Amino-1H-tetrazol
Hbta
Biphenyl-2,20,6,60-tetracarboxylic acid
Hcpt
4-(4H-1,2,4-Triazol-4-yl)benzoic acid
Hpaba
p-Aminobenzoic acid
(S)-Hptz
5-[(2S)-Pyrrolidine-2-yl]-1H-tetrazole
Hpyim
2-(2-Pyridyl)imidazole
Htzf
1H-Tetrazole-5-formic acid
p-H2bdc
1,4-Benzenedicarboxylic acid
m-H2bdc
1,3-Benzenedicarboxylic acid, isophthalic acid
OH-m-H2bdc
5-Hydroxy-1,3-benzenedicarboxylic acid
5-tBu-m-H2bdc
tert-Butyl-1,3-benzenedicarboxylic acid
H2oba
4,40-Oxybis(benzoic acid)
H2bipa
5-Bromoisophthalic acid
H2dba
4,40-Methylenedibenzoic acid
H2Me4BPZ
3,30,5,50-tetramethyl-4,40-bipyrazole
H2nica
Nicotinic acid
3,5-H2PDC
Pyridine-3,5-dicarboxylic acid
H2SA
Succinic acid
H2sdba
4,40-Sulfonyldibenzoic acid
ISAM
Ionic self-assembled monolayer
L-H2tart
L-Tartaric acid
D-H2tart
D-Tartaric acid
H2tzb
1H-Tetrazolate-5-butyric acid
H3btc
1,3,5-Benzene-tricarboxylic acid
H3pidc
2-(Pyridin-4-yl)-1H-imidazole-4,5-dicarboxylic
acid
H3sip
5-Sulfoisophthalic acid
Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:2
This article is licensed under a Creative Commons Attribution 3.0 Unport adc
Acetylenedicarboxylate
anp
2-Amino-5-nitropyridine
BBO
Barium borate, b-BaB2O4
4,40-bipy
4,40-Bipyridine
bimb
4,4-Bis(1H-imidazol-1-yl-methyl)biphenyl
bindc
N,N0-Bis(isonicotinoyl)-(1R,2R)-
diaminocyclohexane
biim-4
1,10-(1,4-Butanediyl)bis(imidazole)
bpp
1,3-Di(pyridin-4-yl)propane
bphy
1,2-Bis(4-pyridyl)hydrazine
btb
1,6-Bis(1,2,4-triazol-1-yl)hexane
CP
Coordination polymers
dcmp
2,5-Dicarboxy-1-methylpyridinium
dob
1,3-Di(2-oxazolinyl)benzene
Hacac
Acetyl acetone
Hain
2-Aminoisonicotinic acid
Haip
5-Aminoisophthalic acid
Hatz
5-Amino-1H-tetrazol
Hbta
Biphenyl-2,20,6,60-tetracarboxylic acid
Hcpt
4-(4H-1,2,4-Triazol-4-yl)benzoic acid
Hpaba
p-Aminobenzoic acid
(S)-Hptz
5-[(2S)-Pyrrolidine-2-yl]-1H-tetrazole
Hpyim
2-(2-Pyridyl)imidazole
Htzf
1H-Tetrazole-5-formic acid
p-H2bdc
1,4-Benzenedicarboxylic acid
m-H2bdc
1,3-Benzenedicarboxylic acid, isophthalic acid
OH-m-H2bdc
5-Hydroxy-1,3-benzenedicarboxylic acid
5-tBu-m-H2bdc
tert-Butyl-1,3-benzenedicarboxylic acid
H2oba
4,40-Oxybis(benzoic acid)
H2bipa
5-Bromoisophthalic acid
H2dba
4,40-Methylenedibenzoic acid
H2Me4BPZ
3,30,5,50-tetramethyl-4,40-bipyrazole
H2nica
Nicotinic acid
3,5-H2PDC
Pyridine-3,5-dicarboxylic acid
H2SA
Succinic acid
H2sdba
4,40-Sulfonyldibenzoic acid
ISAM
Ionic self-assembled monolayer
L-H2tart
L-Tartaric acid
D-H2tart
D-Tartaric acid
H2tzb
1H-Tetrazolate-5-butyric acid
H3btc
1,3,5-Benzene-tricarboxylic acid
H3pidc
2-(Pyridin-4-yl)-1H-imidazole-4,5-dicarboxylic
acid
H3sip
5-Sulfoisophthalic acid
Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:2
This article is licensed under a Creative Commons Attribution 3.0 Unpor adc
Acetylenedicarboxylate
anp
2-Amino-5-nitropyridine
BBO
Barium borate, b-BaB2O4
4,40-bipy
4,40-Bipyridine
bimb
4,4-Bis(1H-imidazol-1-yl-methyl)biphenyl
bindc
N,N0-Bis(isonicotinoyl)-(1R,2R)-
diaminocyclohexane
biim-4
1,10-(1,4-Butanediyl)bis(imidazole)
bpp
1,3-Di(pyridin-4-yl)propane
bphy
1,2-Bis(4-pyridyl)hydrazine
btb
1,6-Bis(1,2,4-triazol-1-yl)hexane
CP
Coordination polymers
dcmp
2,5-Dicarboxy-1-methylpyridinium
dob
1,3-Di(2-oxazolinyl)benzene
Hacac
Acetyl acetone
Hain
2-Aminoisonicotinic acid
Haip
5-Aminoisophthalic acid
Hatz
5-Amino-1H-tetrazol
Hbta
Biphenyl-2,20,6,60-tetracarboxylic acid
Hcpt
4-(4H-1,2,4-Triazol-4-yl)benzoic acid
Hpaba
p-Aminobenzoic acid
(S)-Hptz
5-[(2S)-Pyrrolidine-2-yl]-1H-tetrazole
Hpyim
2-(2-Pyridyl)imidazole
Htzf
1H-Tetrazole-5-formic acid
p-H2bdc
1,4-Benzenedicarboxylic acid
m-H2bdc
1,3-Benzenedicarboxylic acid, isophthalic acid
OH-m-H2bdc
5-Hydroxy-1,3-benzenedicarboxylic acid
5-tBu-m-H2bdc
tert-Butyl-1,3-benzenedicarboxylic acid
H2oba
4,40-Oxybis(benzoic acid)
H2bipa
5-Bromoisophthalic acid
H2dba
4,40-Methylenedibenzoic acid
H2Me4BPZ
3,30,5,50-tetramethyl-4,40-bipyrazole
H2nica
Nicotinic acid
3,5-H2PDC
Pyridine-3,5-dicarboxylic acid
H2SA
Succinic acid
H2sdba
4,40-Sulfonyldibenzoic acid
ISAM
Ionic self-assembled monolayer
L-H2tart
L-Tartaric acid
D-H2tart
D-Tartaric acid
H2tzb
1H-Tetrazolate-5-butyric acid
H3btc
1,3,5-Benzene-tricarboxylic acid
H3pidc
2-(Pyridin-4-yl)-1H-imidazole-4,5-dicarboxylic
acid
H3sip
5-Sulfoisophthalic acid
Open Access Article. This journal is © The Royal Society of Chemistry 2016 Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. In this respect, the
development of MOFs which possess the desired properties
characteristic of metamaterials via chemical methods is very
promising. ima
2-(1H-Imidazole-1-yl)aceta
KDP
Potassium dihydrogen ph
LB
Langmuir–Blodgett
MOF
Metal–organic framework
NLO
Non-linear optics
opy
4,40-(oxybis(4,1-phenylene
ox
Oxalate
ppa
Pipemidic acid
Nit
ili diversification of their final architecture. Attempts to produce
metamaterials via chemical synthesis have been made, but it
appears that this is not at all simple. However, more recently, it
was possible to demonstrate that potential metamaterials
can be obtained via chemical methods. In this respect, the
development of MOFs which possess the desired properties
characteristic of metamaterials via chemical methods is very
promising. ima
2-(1H-Imidazole-1-yl)acetate
KDP
Potassium dihydrogen phosphate, KH2PO4
LB
Langmuir–Blodgett
MOF
Metal–organic framework
NLO
Non-linear optics
opy
4,40-(oxybis(4,1-phenylene))dipyridine
ox
Oxalate
ppa
Pipemidic acid
p-na
p-Nitroaniline
py
Pyridine
pyac
3-(4-Pyridyl)pentane-2,4-dionato
pydc
Pyridine-2,5-dicarboxylate
(E)-4-pyv-4-bza
4-[2-(4-Pyridyl)ethenyl]benzoate
SBU
Secondary building unit
SHG
Second harmonic generation
tbapy
1,3,6,8-Tetrakis(p-benzoate)pyrene
tcf
2-Dicyanomethylene-3-cyano-4,5,5-dimethyl-
2,5-dihydrofuran
titmb
1,3,5-Tris(1-imidazol-1-ylmethyl)-2,4,6-
trimethylbenzene Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Photoluminescence peaks at 2.77 eV and 2.46 eV are coming
from exciton states and organic components of [{Zn2(tbapy)(H2O)2}3.5DEF]n,
respectively. (b) Fit for the edge of absorption by intra- and inter-layer
excitons with Lorentz distribution. The most important goal, however, is finding a correlation
between the method of production, the synthesis parameters,
the properties of the starting materials, and the resulting
physical and chemical characteristics. Studies in this funda-
mental area can bear fruit for applied use as well. If MOFs are
considered as a potential replacement for existing materials for
practical applications in the field of non-linear optics, then
thermal stability and mechanical strength are important. It is
noteworthy that MOFs, which are able to compete in SHG and
at the same time have acceptable thermal stability, already
exist. This demonstrates that competent elaboration of these
materials could improve their competitiveness with respect to
technically important ones not only in terms of the desired
non-linear optical effects, but also in the relative simplicity of
preparation. Fig. 32
The manifestation of excitons in optical spectra. (a) Absorption,
reflection and photoluminescence spectra of single crystals of [{Zn2(tbapy)-
(H2O)2}3.5DEF]n placed on a quartz substrate in air. A single crystal is
excited by continuous white light (100 mW cm2) to obtain absorption
and reflection spectra, and by pulsed UV light (6 ps, 60 MHz, 3.1 eV,
28 W cm2) to generate the photoluminescence. Peak/valley in absorption/
reflection spectra near the fundamental absorption (3.4 eV) is addressed to
exciton states. Photoluminescence peaks at 2.77 eV and 2.46 eV are coming
from exciton states and organic components of [{Zn2(tbapy)(H2O)2}3.5DEF]n,
respectively. (b) Fit for the edge of absorption by intra- and inter-layer
excitons with Lorentz distribution. The
development
of
metal–organic
frameworks
may
transform into a very promising area, namely, obtaining meta-
materials using chemical methods. A transition from physical
methods of production to chemical ones would allow simplifi-
cation of the process for obtaining specific materials, as well as This journal is ©The Royal Society of Chemistry 2016 Chem. Soc. Rev., 2016, 45, 5408--5431 | 5427 Review Article
View Article Online Chem Soc Rev diversification of their final architecture. Attempts to produce
metamaterials via chemical synthesis have been made, but it
appears that this is not at all simple. However, more recently, it
was possible to demonstrate that potential metamaterials
can be obtained via chemical methods. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6
This article is licensed under a Creative Commons Attribution 3.0 Unp 14 J. Wu, J. Valley, S. Ermer, E. Binkley, J. Kenney, G. Lipscomb
and R. Lytel, Appl. Phys. Lett., 1991, 58, 225–227. 41 A. C. Wibowo, M. D. Smith, J. Yeon, P. S. Halasyamani and
H.-C. zur Loye, J. Solid State Chem., 2012, 195, 94–100. 15 J. Wu, E. Binkley, J. Kenney, R. Lytel and A. Garito, J. Appl. Phys., 1991, 69, 7366–7368. 42 S. Ma, J. A. Fillinger, M. W. Ambrogio, J.-L. Zuo and
H.-C. Zhou, Inorg. Chem. Commun., 2007, 10, 220–222. 16 M. Era, T. Tsutsui and S. Saito, Stud. Interface Sci., 1996, 4,
287–321. 43 Y.-J. Liu, J.-S. Huang, S. Sin-Yin Chui, C.-H. Li, J.-L. Zuo,
N. Zhu and C.-M. Che, Inorg. Chem., 2008, 47, 11514–11518. 17 S. J. Lalama and A. F. Garito, Phys. Rev. A: At., Mol., Opt. Phys., 1979, 20, 1179–1194. 44 D. W. Lee, V. Jo and K. M. Ok, J. Solid State Chem., 2012,
194, 369–374. 18 P. Guyot-Sionnest, W. Chen and Y. R. Shen, Phys. Rev. B:
Condens. Matter Mater. Phys., 1986, 33, 8254–8263. 45 W.-W. Zhou, W. Zhao, B. Wei, F.-W. Wang, Y.-H. Chen,
W.-Y. Fang and X. Zhao, Inorg. Chim. Acta, 2012, 386,
17–21. 19 P. Ye and Y. R. Shen, Phys. Rev. B: Condens. Matter Mater. Phys., 1983, 28, 4288–4294. 20 T. F. Heinz, H. W. K. Tom and Y. R. Shen, Phys. Rev. A: At.,
Mol., Opt. Phys., 1983, 28, 1883–1885. 46 G. Hu, H. Zhang, H. Miao, J. Wang and Y. Xu, J. Solid State
Chem., 2015, 229, 208–212. 21 P. Guyot-Sionnest, W. Chen and Y. R. Shen, Phys. Rev. B:
Condens. Matter Mater. Phys., 1986, 33, 8254–8263. 47 X. Xu, Y.-H. Yu, G.-F. Hou, X.-W. Li, C.-Y. Ren and D.-S. Ma,
Polyhedron, 2016, 112, 61–66. 48 Y.-J. Ping, R.-Y. Yan, G.-C. Zhao, L. Qin and H.-G. Zheng,
Inorg. Chem. Commun., 2015, 61, 136–139. 22 P. Guyot-Sionnest and Y. R. Shen, Phys. Rev. B: Condens. Matter Mater. Phys., 1987, 35, 4420–4426. 23 T. F. Heinz, C. K. Chen, D. Ricard and Y. R. Shen, Phys. Rev. Lett., 1982, 48, 478–481. 49 J. N. Babu Reddy, S. Vanishri, G. Kamath, S. Elizabeth,
H. L. Bhat, D. Isakov, M. Belsley, E. de Matos Gomes and
T. L. Aroso, J. Cryst. Growth, 2009, 311, 4044–4049. 24 I. R. Girling, N. A. Cade, P. V. Kolinsky and C. M. Montgomery,
Electron. Lett., 1985, 21, 169–170. 50 Z. Xue, H. References 1 B. E. A. Saleh and M. C. Teich, Fundamentals of Photonics,
John Wiley & Sons, Inc, 2nd edn, 2007. 1 B. E. A. Saleh and M. C. Teich, Fundamentals of Photonics,
John Wiley & Sons, Inc, 2nd edn, 2007. 2 A. A. Blistanov, Crystals of Quantum and Nonlinear Optics,
MISIS, Moscow, 2000, (in Russian). 3 B. N. Grechushnikov, I. S. Zheludev, A. V. Zalesski, S. A. Pikin, S. A. Semiletov, A. A. Urusovskaya, I. G. Chistyakov and
L. A. Shuvalov, Modern Crystallography. Physical Properties of
Crystals, Moscow, 1981, vol. 4 (in Russian). 4 C. Chen, Y. Wu and R. Li, J. Cryst. Growth, 1990, 99,
790–798. 4 C. Chen, Y. Wu and R. Li, J. Cryst. Growth, 1990, 99,
790–798. 5 C. Chen, J. Synth. Cryst., 2001, 30, 36–42. 6 R. H. French, J. W. Ling, F. S. Ohuchi and C. T. Chen, Phys. Rev. B: Condens. Matter Mater. Phys., 1991, 44, 8496–8502. 6 R. H. French, J. W. Ling, F. S. Ohuchi and C. T. Chen, Phys. Rev. B: Condens. Matter Mater. Phys., 1991, 44, 8496–8502. 7 W.-D. Cheng and J.-X. Lu, Chin. J. Struct. Chem., 1997, 16,
81–90. 7 W.-D. Cheng and J.-X. Lu, Chin. J. Struct. Chem., 1997, 16,
81–90. This journal is © The Royal Society of Chemistry 2016 5428 | Chem. Soc. Rev., 2016, 45, 5408--5431 View Article Online Review Article Chem Soc Rev 8 D. Elmeri, L. Davis, S. Velsko, E. K. Graham and A. Zalkin,
J. Appl. Phys., 1987, 62, 1968–1983. 34 N. L. Rosi,
M. Eddaoudi,
J. Kim,
M. O’Keefi
and
O. M. Yaghi, CrystEngComm, 2002, 68, 401–404. 9 L. K. Cheng, W. Bosenberg and C. L. Tang, Prog. Cryst. Growth Charact., 1990, 20, 9–57. 35 K. M. Ok, E. Ok Chia and P. S. Halasyamani, Chem. Soc. Rev., 2006, 35, 710–717. 10 P. P. Fedorov, A. E. Kokh and N. G. Kononova, Russ. Chem. Rev., 2002, 71, 651–671. 36 Z. Guo, R. Cao, X. Wang, H. Li, W. Yuan, G. Wang, H. Wu
and J. Li, J. Am. Chem. Soc., 2009, 131, 6894–6895. n Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 11 F. Quist, C. M. L. Vande Velde, D. Didier, A. Teshome,
I. Asselberghs, K. Clays and S. Sergeyev, Dyes Pigm., 2009,
81, 203–210. 37 Q. Ye, Y.-Z. Tang, X.-S. Wang and R.-G. Xiong, Dalton
Trans., 2005, 1570–1573. 38 L. Cheng, H. Hu, L. Zhang and S. Gou, Inorg. Chem. Commun., 2012, 15, 202–207. 12 L. Cheng, R. Foss, G. Meredith, W. Tam and F. Zumsteg,
Mater. Res. Soc. Symp. Proc., 1992, 247, 27–39. 39 Y. Xiao, J.-S. Guo, F.-K. Zheng and G.-C. Guo, Inorg. Chem. Commun., 2016, 70, 7–9. 13 R. Jeng, Y. Chen, B. Mandal, J. Kumar and S. Tripathy,
Mater. Res. Soc. Symp. Proc., 1992, 247, 111–117. 40 L. Wang, Y. Ye, L. Zhang, Q. Chen, X. Ma, Z. Zhang and
S. Xiang, Inorg. Chem. Commun., 2015, 60, 19–22. en Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 63 L. Li, Z. Wang, Q. Chen, X. Zhou, T. Yang, Q. Zhao and
W. Huang, J. Solid State Chem., 2015, 231, 47–52. 91 O. R. Evans, R. G. Xiong, Z. Wang, G. K. Wong and W. Lin,
Angew. Chem., Int. Ed., 1999, 38, 536–538. 64 Y.-H. Luo, L.-L. Gu, X.-Y. Yu, F.-X. Yue, X. Chen and
H. Zhang, Inorg. Chem. Commun., 2014, 40, 176–180. 92 D. W. Fu, W. Zhang and R. G. Xiong, Dalton Trans., 2008,
3946–3948. 65 P.-F. Wang, M.-G. Sheng, X.-S. Wu and X. Wang, Inorg. Chim. Acta, 2011, 379, 135–139. 93 W. Lin, L. Ma and O. R. Evans, Chem. Commun., 2000,
2263–2264. 66 X.-F. Wang and G-X. Liu, Inorg. Chim. Acta, 2013, 406, 223–229. 94 W. Lin, Z. Wang and L. Ma, J. Am. Chem. Soc., 1999, 121,
11249–11250. 67 L. Li, D. Sun, Zh. Wang, X. Song and S. Sun, Solid State Sci.,
2009, 11, 1040–1043. 95 O. R. Evans and W. Lin, Chem. Mater., 2001, 13, 2705–2712. 68 Q.-Y. Chen, Y. Li, F.-K. Zheng, W.-Q. Zou, M. F. Wu,
G. C. Guo, A. Q. Wu and J.-Sh. Huang, Inorg. Chem. Commun., 2008, 11, 969–971. 96 H. Zhao, Z.-R. Qu, H.-Y. Ye and R.-G. Xiong, Chem. Soc. Rev., 2008, 37, 84–100. 69 S. D. Huang, R.-G. Xiong, J. Han and B. R. Weiner, Inorg. Chim. Acta, 1999, 294, 95–98. 97 M. F. Wu, G. Xu, F. K. Zheng, Z. F. Liu, S. H. Wang,
G. C. Guo and J. S. Huang, Inorg. Chem. Commun., 2011, 14,
333–336. 70 Y. Zhao, L. Luo, C. Liu, M. Chen and W.-Y. Sun, Inorg. Chem. Commun., 2011, 14, 1145–1148. 98 L.-Z. Wang, Z.-R. Qu, H. Zhao, X.-S. Wang, R.-G. Xiong and
Z.-L. Xue, Inorg. Chem., 2003, 42, 3969–3971. 71 Y.-H. Tan, J.-X. Gao, Z.-F. Gu, Q. Xu, C.-S. Yang, Y.-S. Luo,
B. Wang, Y.-Z. Tang and H.-R. Wen, Polyhedron, 2015, 101,
239–243. 99 R. G. Pearson, J. Am. Chem. Soc., 1969, 91, 4947–4955. 100 R. G. Pearson, J. Mol. Struct.: THEOCHEM, 1983, 103, 25–34. 72 D. Marabello, P. Antoniotti, P. Benzi, C. Canepa, E. Diana,
L. Operti, L. Mortati and M. P. Sassi, J. Mater. Sci., 2015, 50,
4330–4341. 101 P. A. Maggard, C. L. Stern and K. R. Poeppelmeier, J. Am. Chem. Soc., 2001, 123, 7742–7743. 102 X. A. Chen, X. Chang, H. Zang, Q. Wang and W. Q. Xiao,
J. Alloys Compd., 2005, 396, 255–259. en Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. 73 L.-N. Duan, Q.-Q. Dang, C.-Y. Han and X. M. Zhang, Dalton
Trans., 2015, 44, 1800–1804. 103 E. O. Chi, K. M. Ok, Y. Porter and P. S. Halasyamani, Chem. Mater., 2006, 18, 2070–2074. 74 D.-K. Bucar, G. S. Papaefstathiou, T. D. Hamilton, Q. L. Chu, I. G. Georgiev and L. R. MacGillivray, Eur. J. Inorg. Chem., 2007, 4559–4568. 104 X. A. Chen, L. Zhang, X. Chang, H. Xue, H. Zang,
W. Q. Xiao, X. Song and H. Yan, J. Alloys Compd., 2007,
428, 54–58. 75 E. R. Parnham and R. E. Morris, Acc. Chem. Res., 2007, 40,
1005–1013. 105 H. Y. Chang, S.-H. Kim, P. S. Halasyamani and K. M. Ok,
J. Am. Chem. Soc., 2009, 131, 2426–2427. 76 G. Nickerl, A. Henschel, R. Grunker, K. Gedrich and
S. Kaskel, Chem. Ing. Tech., 2011, 83, 90–103. 106 H.-Y. Chang, S.-H. Kim, K. M. Ok and P. S. Halasyamani,
J. Am. Chem. Soc., 2009, 131, 6865–6873. 77 S. Mendiratta, C.-H. Lee, S.-Y. Lee, Y.-C. Kao, B.-C. Chang,
Y.-H. Lo and K.-L. Lu, Molecules, 2015, 20, 8941–8951. 77 S. Mendiratta, C. H. Lee, S. Y. Lee, Y. C. Kao, B. C. Chang,
Y.-H. Lo and K.-L. Lu, Molecules, 2015, 20, 8941–8951. 107 C. Sun, T. Hu, X. Xu and J. G. Mao, Dalton Trans., 2010, 39,
7960–7967. 78 L.-Z. Chen, Y. Huang, R.-G. Xiong and H.-W. Hu, J. Mol. Struct., 2010, 963, 16–21. 108 B. Yang, C. Hu, X. Xu, C. Sun, H. Z. Jian and J. G. Mao,
Chem. Mater., 2010, 22, 1545–1550. 79 B. Chen and G. Qian, Metal-Organic Frameworks for Photo-
nics Applications, Springer, Berlin, Heidelberg, 2014. 109 D. W. Lee, S.-J. Oh, P. S. Halasyamani and K. M. Ok, Inorg. Chem., 2011, 50, 4473–4480. 80 C. Wang, T. Zhang and W. Lin, Chem. Rev., 2012, 112,
1084–1104. 110 E.-a. Kim, D. W. Lee and K. M. Ok, J. Solid State Chem.,
2012, 195, 149–154. 81 C. Pettinari, A. Ta˘ba˘caru and S. Galli, Coord. Chem. Rev.,
2016, 307, 1–31. 111 M. Joffre, D. Yaron, R. J. Silbey and J. Zyss, J. Chem. Phys.,
1992, 97, 5607–5615. 82 R. Ahlers and U. Ruschewitz, Solid State Sci., 2009, 11,
1058–1064. 112 W. Lin, Z. Wang and L. Ma, J. Am. Chem. Soc., 1999, 121,
11249–11250. 83 J. D. Lin, X. F. Long, P. Lin and S. W. Du, Cryst. Growth
Des., 2010, 10, 146–157. 113 Y. Liu, G. Li, X. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6
This article is licensed under a Creative Commons Attribution 3.0 Unp Zhang, T. Sheng, Y. Wen, Y. Wang, S. Hu, H. Li,
C. Zhuo and X. Wu, Inorg. Chem. Commun., 2015, 55,
99–102. 25 D. B. Neal, M. C. Petty, G. G. Roberts, M. M. Ahmad,
W. J. Feast, I. R. Girling, N. A. Cade, P. V. Kolinsky and
I. R. Peterson, Electron. Lett., 1986, 22, 460–481. 51 M.-F. Wu, G. Xu, F.-K. Zheng, Z.-F. Liu, S.-H. Wang,
G.-C. Guo and J.-S. Huang, Inorg. Chem. Commun., 2011,
14, 333–336. 26 W. Lin, S. Yitzchaik, W. Lin, A. Malik, M. K. Durbin,
A. G. Richter, G. K. Wong, P. Dutta and T. Marks, Angew. Chem., 1995, 34, 1497–1499. 52 G.-X. Liu, X.-F. Wang and H. Zhou, J. Solid State Chem.,
2013, 199, 305–316. 27 X. Yang, D. McBranch, B. Swanson and D. Li, Mater. Res. Soc. Symp. Proc., 1995, 392, 27–32. 53 L. Guan and Y. Wang, J. Solid State Chem., 2015, 230,
243–248. 28 A. Ulman, Chem. Rev., 1996, 96, 1533–1554. 54 C. Yang, J. Wang, W. Wang and W. Zhan, J. Solid State
Chem., 2011, 184, 2485–2489. 29 Z. Xu, T. Zhang, W. Lin and G. Wong, J. Phys. Chem., 1993,
97, 6958–6960. 30 G. Decher and J. D. Hong, Thin Solid Films, 1992, 210/211,
831–835. 55 Y.-T. Wang, G.-M. Tang, Y. Wu, X.-Y. Qin and D.-W. Qin,
J. Mol. Struct., 2007, 831, 61–68. 31 G. Decher, Y. Lvov and J. Schmitt, Thin Solid Films, 1994,
244, 772–777. 56 X.-F. Huang, Y.-H. Li, Q. Wu, Q. Ye and R.-G. Xiong, Inorg. Chim. Acta, 2005, 358, 2097–2100. 32 A. V. Vinogradov, V. A. Milichko, H. Zaake-Hertling,
A. Aleksovska, S. Gruschinski, S. Schmorl, B. Kersting,
E. M. Zolnhofer, J. Sutter, K. Meyer, P. Lo¨nnecke and
E. Hey-Hawkins, Dalton Trans., 2016, 45, 7183–7194. 57 H. Lun, X. Li, X. Wang, H. Li, Y. Li and Y. Bai, J. Mol. Struct., 2017, 1127, 662–667. 58 L.-Z. Chen, D.-D. Huang, J.-Z. Ge and F.-M. Wang, Inorg. Chim. Acta, 2013, 406, 95–99. 59 Z.-X. Xu, Y. Liu and J. Zhang, Inorg. Chem. Commun., 2016,
67, 44–46. 33 J. L. C. Rowsell and O. M. Yaghi, Microporous Mesoporous
Mater., 2004, 73, 3–14. This journal is ©The Royal Society of Chemistry 2016 Chem. Soc. Rev., 2016, 45, 5408--5431 | 5429 View Article Online View Article Online Chem Soc Rev 87 P. A. Savarimuthu, Inorg. Chem. Commun., 2008, 11, 791–794. 60 M. Li, J. Yang, Y.-Y. Liu and J.-F. Open Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6
This article is licensed under a Creative Commons Attribution 3.0 Unp Ma, Dyes Pigm., 2015, 120,
136–146. varimuthu, Inorg. Chem. Commun., 2008, 11, 791–794 88 F. Sun and G. Zhu, Inorg. Chem. Commun., 2013, 38,
115–118. 61 Z.-L. Zhang, X.-Q. Yao, N. An, H.-C. Ma, Z.-Q. Lei and
J.-C. Liu, Inorg. Chem. Commun., 2014, 45, 127–130. 89 F. Wang, Y.-X. Tan, H. Yang, Y. Kang and J. Zhang, Chem. Commun., 2012, 48, 4842–4844. 62 J. Zhu, H. Song, J. Sun, P. Yan, G. Hou and G. Li, Synth. Met., 2014, 192, 29–36. 90 H.-N. Wang, X. Meng, C. Qin, X.-L. Wang, G.-S. Yang and
Z.-M. Su, Dalton Trans., 2012, 41, 1047–1053. Chem. Soc. Rev., 2016, 45, 5408--5431 | 5431 This journal is ©The Royal Society of Chemistry 2016 116 W. Lin, L. Ma and O. R. Evans, Chem. Commun., 2000,
2263–2264.
121 B. Luther-Davies and M. Samoc, Curr. Opin. Solid State
Mater. Sci., 1997, 2, 213–219. 117 O. R. Evans and W. Lin, Acc. Chem. Res., 2002, 35,
511–522.
122 J.-P. Zou, Q. Peng, Zh. Wen, G.-Sh. Zeng, Q.-J. Xing and
G.-C. Guo, Cryst. Growth Des., 2010, 10, 2613–2619. en Access Article. Published on 20 September 2016. Downloaded on 10/24/2024 6:28:13 AM.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Li and Y. Cui, Angew. Chem., Int. Ed., 2007,
46, 6301–6304. 84 J. D. Lin, S. T. Wu, Z. H. Li and S. W. Du, Dalton Trans.,
2010, 39, 10719–10728. 114 O. R. Evans
and
W. Lin,
Chem. Mater.,
2001,
13,
2705–2712. 85 D. Shaowu and Z. Huabin, Struct. Bonding, 2014, 145–166. 115 O. R. Evans, R. G. Xiong, Z. Y. Wang, G. K. Wong and
W. Lin, Angew. Chem., Int. Ed., 1999, 38, 536–538. 86 Q. Ye, Y-H. Li, Y.-M. Song, X.-F. Huang, R.-G. Xiong and
Z. Xue, Inorg. Chem., 2005, 44, 3618–3625. 5430 | Chem. Soc. Rev., 2016, 45, 5408--5431 This journal is © The Royal Society of Chemistry 2016 View Article Online Review Article Chem Soc Rev Chem Soc Rev 116 W. Lin, L. Ma and O. R. Evans, Chem. Commun., 2000,
2263–2264. 121 B. Luther-Davies and M. Samoc, Curr. Opin. Solid State
Mater. Sci., 1997, 2, 213–219. 117 O. R. Evans and W. Lin, Acc. Chem. Res., 2002, 35,
511–522. 122 J.-P. Zou, Q. Peng, Zh. Wen, G.-Sh. Zeng, Q.-J. Xing and
G.-C. Guo, Cryst. Growth Des., 2010, 10, 2613–2619. 122 J.-P. Zou, Q. Peng, Zh. Wen, G.-Sh. Zeng, Q.-J. Xing and
G.-C. Guo, Cryst. Growth Des., 2010, 10, 2613–2619. 118 H. Zhang, X. Wang, K. Zhang and B. K. Teo, Coord. Chem. Rev., 1999, 183, 157–195. 123 Z. Sun, T. Chen, N.-n. Cai, J.-w. Chen, L. Li, Y. Wang, J. Luo
and M. Hong, New J. Chem., 2011, 35, 2804–2810. 118 H. Zhang, X. Wang, K. Zhang and B. K. Teo, Coord. Chem. Rev., 1999, 183, 157–195. 123 Z. Sun, T. Chen, N.-n. Cai, J.-w. Chen, L. Li, Y. Wang, J. Luo
and M. Hong, New J. Chem., 2011, 35, 2804–2810. 119 Y. F. Zhou, D. Q. Yuan, B. L. Wu, R. H. Wang and
M. C. Hong, New J. Chem., 2004, 28, 1590–1594. 124 A. V. Vinogradov, H. Zaa
P. Lo¨nnecke, G. A. Seisen 119 Y. F. Zhou, D. Q. Yuan, B. L. Wu, R. H. Wang and
M. C. Hong, New J. Chem., 2004, 28, 1590–1594. 124 A. V. Vinogradov, H. Zaake-Hertling, A. S. Drozdov,
P. Lo¨nnecke, G. A. Seisenbaeva, V. G. Kessler, V. V. Vinogradov and E. Hey-Hawkins, Chem. Commun., 2015,
51, 17764–17767. 120 P. Ayyappan, G. Sirokman, O. R. Evans, T. H. Warren and
W. Lin, Inorg. Chim. Acta, 2004, 357, 3999–4004. This journal is ©The Royal Society of Chemistry 2016
|
https://openalex.org/W2965590751
|
http://www.scielo.br/pdf/sdeb/v43n121/0103-1104-sdeb-43-121-0450.pdf
|
Portuguese
| null |
Centros de Atenção Psicossocial - álcool e drogas: perfil dos usuários
|
Saúde em Debate
| 2,019
|
cc-by
| 6,807
|
Centros de Atenção Psicossocial – álcool e
drogas: perfil dos usuários
Psychosocial Care Centers – alcohol and drugs: users’ profile Erika Renata Trevisan1, Sybelle de Souza Castro2 Erika Renata Trevisan1, Sybelle de Souza Castro2 DOI: 10.1590/0103-1104201912113 RESUMO O estudo objetivou descrever o perfil dos usuários em tratamento nos Centros de Atenção
Psicossocial – álcool e drogas (CAPSad) da região do Triângulo Mineiro, em Minas Gerais. Estudo
de tipo transversal, com amostra de 369 usuários. Utilizou-se um instrumento contendo variáveis
sociodemográficas e sobre o atendimento no CAPSad; sobre substâncias psicoativas utilizadas
ao longo da vida e no último mês; idade de uso inicial; internação e medicação decorrentes do
uso; tempo e modalidade de tratamento. Realizaram-se análise estatística descritiva e testes
t-Student, não paramétrico de Mann-Whitney, análise de variância paramétrica (ANOVA-F),
de comparações múltiplas de Dunn. Verificaram-se maiores percentuais de homens (80,5%),
com idade entre 41 e 60 anos (45,8%), sem companheiro(a) (55,2%), com ensino fundamental
incompleto (38,4%), desempregados (34,7%) e em tratamento entre 1 e 5 anos (62,9%). O álcool
foi a substância mais utilizada ao longo da vida (89,7%); e no último mês (77,8%). Este estudo
reforça a necessidade de resgate da autonomia, da reinserção social, do trabalho com valor social
e dos direitos de cidadania, a partir de uma atenção especializada e individualizada. As redes
sociais de apoio, a intersetorialidade e a articulação das Redes de Atenção Psicossocial devem
ser a base da transformação para que essas questões se concretizem na prática assistencial. PALAVRAS-CHAVE Saúde mental. Epidemiologia. Pesquisa sobre serviços de saúde. Serviços
de saúde mental. Transtornos relacionados ao uso de substâncias. ABSTRACT The study aimed to describe the profile of users being treated in the Psychosocial
Care Centers – alcohol and drugs (CAPSad) of the Triângulo Mineiro region of Minas Gerais. A
cross-sectional study, with sample of 369 users into treatment. An instrument was used contain-
ing sociodemographic variables and about care in CAPSad; about psychoactive substances used
throughout life and in the last month; age of initial use of psychoactive substances; hospitalization
and medication resulting from the use; time and modality of treatment. Descriptive statistical
analysis and Student’s t-tests, non-parametric Mann-Whitney, parametric analysis of variance
(ANOVA-F), and Dunn’s multiple comparisons were performed. There was a higher percentage of
men (80.5%), age between 41 and 60 years (45.8%), without partner (55.2%), incomplete elementary
school (38.4%), unemployed (34.7%) and in treatment between 1 and 5 years (62.9%). Alcohol was
the most used substance throughout life (89.7%); and in the last month (77.8%). 450 450 ARTIGO ORIGINAL | ORIGINAL ARTICLE 1 Universidade Federal do
Triângulo Mineiro (UFTM),
Departamento de Terapia
Ocupacional – Uberaba
(MG), Brasil.
erikatouftm@hotmail.com
2 Universidade Federal do
Triângulo Mineiro (UFTM),
Departamento de Saúde
Coletiva – Uberaba (MG),
Brasil. Este é um artigo publicado em acesso aberto (Open Access) sob a licença Creative
Commons Attribution, que permite uso, distribuição e reprodução em qualquer
meio, sem restrições, desde que o trabalho original seja corretamente citado. 1 Universidade Federal do
Triângulo Mineiro (UFTM),
Departamento de Terapia
Ocupacional – Uberaba
(MG), Brasil.
erikatouftm@hotmail.com Introdução álcool e outras drogas e de seus familiares,
em seus diferentes níveis de complexidade1. As políticas atuais de saúde mental e de
atenção psicossocial desenvolvidas no âmbito
do Sistema Único de Saúde (SUS), resultan-
tes do movimento da reforma psiquiátrica,
têm uma relação direta com o movimento da
reforma sanitária, que surgiu em meados da
década de 1970 e constituiu-se no processo de
amplas mobilizações da sociedade brasileira
pela redemocratização1. Na Raps, os Centros de Atenção Psicossocial
(Caps) foram designados como locais de refe-
rência para o tratamento da população adulta
com transtornos mentais severos e persis-
tentes, os Centros de Atenção Psicossocial
Infanto-Juvenil (CAPSi) são especializados
em crianças e adolescentes com transtornos
mentais, e os Centros de Atenção Psicossocial –
álcool e drogas (CAPSad) destinados às pessoas
com problemas decorrentes do uso de álcool
e outras drogas3. Esse processo sociopolítico possibilitou di-
ferentes e intensas transformações na atenção
à saúde mental nas últimas três décadas. O
movimento de reforma psiquiátrica consolidou
mudanças significativas na forma de tratar e
entender os transtornos mentais, que passaram
a ser cuidados nos serviços substitutivos ao
hospital psiquiátrico e na superação do modelo
psiquiátrico, pautado na exclusão social, na
violência e na cronificação do sujeito2. Essa mudança de paradigma do cuidado das
pessoas com problemas decorrentes do uso de
álcool e outras drogas deve incluir a relação
que se estabelece com o usuário, a equipe, a
família e a comunidade. A mudança de papéis,
a democratização das instituições, o envolvi-
mento e a responsabilização da comunidade
devem somar-se aos objetivos técnicos do tra-
tamento. A partir disso, o objeto de intervenção
torna-se mais complexo e interdisciplinar,
assim como as práticas e os saberes tradicio-
nais devem ser reconstruídos para responder
às demandas dessa transformação4. Centros de Atenção Psicossocial – álcool e
drogas: perfil dos usuários
Psychosocial Care Centers – alcohol and drugs: users’ profile This study rein-
forces the need to rescue autonomy, social reintegration, work with social value, citizenship rights
based on specialized and individualized attention. Social support networks, intersectoriality and SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 451 Centros de Atenção Psicossocial – álcool e drogas: perfil dos usuários the articulation of the Psychosocial Attention Networks should be the basis of the transformation
so that these issues are concretized in the care practice. KEYWORDS Mental health. Epidemiology. Health services research. Mental health services. Substance-related disorders. Métodos overdose. O consumo de heroína e as mortes
por overdose aumentaram nos últimos dois
anos em alguns países da América do Norte,
da Europa Ocidental e Central. Os opio-
ides continuam a representar os maiores
riscos de danos à saúde entre as principais
drogas. Com exceção do álcool e do tabaco,
a maconha é a droga mais usada ao redor do
mundo. O acesso a serviços de tratamento,
com base em evidências científicas, repre-
senta outro grande desafio apontado pelo
relatório, pois somente uma em cada seis
pessoas que necessitam de atendimento
tem acesso aos serviços5. Trata-se de um estudo descritivo com abor-
dagem quantitativa do tipo transversal. A pes-
quisa foi aprovada pelo Comitê de Ética em
Pesquisa por meio da Plataforma Brasil, com
parecer consubstanciado de número 1.139.451
e CAAE 45867315.9.0000.5154. Os dados relativos aos clientes foram
obtidos por meio dos prontuários, e a pes-
quisa foi realizada nos três CAPSad da região
do Triângulo Mineiro, sendo que um deles é
CAPSad II e dois são CAPSad III. Os CAPSad II
atendem cidades e/ou regiões com pelo menos
70 mil habitantes durante o dia. Os CAPSad III
possuem atendimento noturno e observação,
funcionam 24 horas e atendem cidades e ou
regiões com pelo menos 150 mil habitantes. No Brasil, aproximadamente 12,3% da
população é considerada dependente de
álcool, de acordo com os critérios da 10ª
Classificação Internacional de Doenças
(CID-10) e do IV Manual Diagnóstico e
Estatístico de Transtornos Mentais (DSM-
IV), sendo que a prevalência é de 17,1% entre
a população masculina e 5,7% na população
feminina, que são prevalências consideradas
altas quando comparadas às de outras condi-
ções de saúde. Além dos problemas de saúde
física, as pessoas com transtornos causados
pelo uso de álcool e outras drogas podem
ter sofrimentos psicológicos e psicossociais
graves, problemas interpessoais, perda de
emprego, dificuldades de aprendizado, além
de problemas legais6. A população assistida por esses serviços
totaliza 920.033 habitantes em duas macror-
regiões de saúde do estado de Minas Gerais:
Triângulo Norte e Triângulo Sul. No período da coleta dos dados, foi realiza-
do um levantamento dos clientes que estavam
em atendimento nos CAPSad, para a realização
do cálculo e do sorteio da amostra. O sorteio
foi realizado no Programa SPSS-versão 21. O
cálculo do tamanho amostral considerou uma
prevalência de uso de múltiplas substâncias
psicoativas de 39,0%, uma precisão de 4% e
um intervalo de confiança de 95%. Introdução Diversas estratégias foram desenvolvidas
nos campos técnico, assistencial, social, po-
lítico e jurídico, e, em 2011, foi instituída a
Rede de Atenção Psicossocial (Raps) a partir
da Portaria GM/MS nº 3.088, de dezembro de
2011, que possibilita uma nova dimensão ao
conjunto das ações em saúde mental no SUS,
com a garantia da articulação e da integração
dos serviços de atenção das redes de saúde no
território, qualificando o cuidado por meio do
acolhimento, do acompanhamento contínuo e
da atenção às urgências à atenção psicossocial
da população com transtornos mentais e com
necessidades decorrentes do uso do crack, De acordo com o ‘Relatório Mundial sobre
Drogas’, publicado em 2016 pelo Escritório
das Nações Unidas sobre Drogas e Crime
(UNODC), aproximadamente 5% da po-
pulação adulta e 250 milhões de pessoas
entre 15 e 64 anos usaram pelo menos uma
droga em 2014. Com relação à mortalidade
relacionada ao uso de drogas, 207 mil mortes
foram relatadas, sendo um terço delas por SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 Trevisan ER, Castro SS 452 Métodos Para uma
população finita de 963 clientes dos serviços,
obteve-se o tamanho amostral de 369 partici-
pantes a serem incluídos no estudo. A coleta
dos dados foi realizada no período de maio a
agosto de 2016. Embora nem todo usuário de substâncias
psicoativas deva ser considerado dependen-
te, é preciso ressaltar que, de acordo com a
Organização Mundial da Saúde (OMS), 10%
das populações dos centros urbanos de todo
o mundo, incluindo o Brasil, necessitam de
assistência integral à saúde para eliminar ou
minimizar os danos que essas substâncias
podem causar. Nesse sentido, os CAPSad são
os serviços públicos de saúde preconizados
para o tratamento dessa população no Brasil3. Foi desenvolvido um instrumento para a
coleta de dados com as seguintes variáveis:
sexo; idade; estado civil; escolaridade; situa-
ção de trabalho; demanda do atendimento no
CAPSad; substâncias psicoativas utilizadas ao
longo da vida e no último mês; idade de uso
inicial das substâncias psicoativas; internação
e medicação decorrentes do uso de substâncias
psicoativas; tempo de permanência no CAPSad
e modalidade de tratamento. Inicialmente,
constavam do instrumento variáveis como: Este estudo, portanto, teve como objetivo
descrever o perfil epidemiológico e os tipos
de substâncias psicoativas utilizadas pelos
usuários dos CAPSad da região do Triângulo
Mineiro, no estado de Minas Gerais. SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 453 Centros de Atenção Psicossocial – álcool e drogas: perfil dos usuários análise de variância paramétrica (ANOVA-F),
seguida do teste de comparação múltipla de
Tukey. Quando a normalidade dos dados e a
homogeneidade das variâncias não foram sa-
tisfeitas, a ANOVA não paramétrica foi usada
pelo teste de Kruskal-Wallis, seguido do teste
de comparações múltiplas de Dunn. O nível
de significância para todos testes foi de 5%. renda, religião, problemas psicossociais e
comorbidades relacionadas ao uso de subs-
tâncias, entretanto, essas informações não
foram encontradas na maioria dos prontuá-
rios investigados, não sendo possível a análise
desses dados. Para a análise dos dados, foi utilizado o
teste t-Student, quando as variáveis epi-
demiológicas e sociodemográficas tinham
apenas duas categorias e os dados apresen-
tassem normalidade. Quando a normalidade
não foi satisfeita, foi utilizado o teste não
paramétrico de Mann-Whitney. Quando
apresentaram mais de duas categorias nas
variáveis epidemiológicas e sociodemográfi-
cas, os dados apresentaram normalidade e as
variâncias foram homogêneas, foi utilizada a Resultados Verificou-se maior percentual do sexo mas-
culino (80,5%), entre 41 e 60 anos (45,8%) e
sem companheiro(a) (55,2%). A maioria possui
ensino fundamental incompleto (38,4%) e está
desempregada (34,7%) (tabela 1). Tabela 1. Perfil sociodemográfico dos clientes atendidos nos CAPSad da Região do Triângulo Mineiro (MG), Brasil, 2016
Variáveis/Categorias
Distribuição
(n = 369)
%
Sexo
Masculino
297
80,5
Feminino
67
18,2
Não informado
5
1,3
Idade (em anos)
Até 20 anos
8
2,2
De 21 a 40 anos
149
40,4
De 41 a 60 anos
169
45,8
Acima de 61 anos
34
9,2
Não informado
9
2,4
Estado civil
Solteiro
147
39,8
Casado
91
24,7
União estável
46
12,5
Viúvo
9
2,4
Divorciado
48
13,0
Não informado
28
7,6
Escolaridade
Analfabeto
9
2,4
Ensino fundamental I incompleto
71
19,2
Ensino fundamental I completo
30
8,1 ográfico dos clientes atendidos nos CAPSad da Região do Triângulo Mineiro (MG), Brasil, 2016 SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 Trevisan ER, Castro SS 454 Tabela 1. (cont.)
Ensino fundamental II incompleto
71
19,2
Ensino fundamental II completo
45
12,2
Ensino médio incompleto
27
7,3
Ensino médio completo
42
11,4
Ensino superior incompleto
8
2,2
Ensino superior completo
3
0,9
Não informado
63
17,1
Tipo de ocupação
Carteira assinada
67
18,2
Cooperativa
1
0,3
Autônomo
51
13,8
Desempregado
128
34,7
Aposentado por tempo de trabalho
15
4,1
Aposentado por invalidez
3
0,8
Não informado
104
28,2
Fonte: Banco de dados da pesquisa sobre o perfil dos clientes dos CAPSad da região do Triângulo Mineiro (MG), 2016. CAPSad que já haviam sido internados por uso
de substâncias psicoativas (39,8%), entretanto,
não constava tal informação nos prontuários
para 26,3% dos participantes do estudo. Faziam
uso de medicações relacionadas aos problemas
decorrentes do uso das substâncias 64,8%, e a
modalidade de tratamento mais utilizada nos
CAPSad foi a semi-intensiva (61,0%) (tabela 2). A maioria dos clientes está em tratamento
entre 1 e 5 anos (62,9%); houve maior percentual
de usuários que chegaram até o CAPSad por
meio de encaminhamentos (44,7%), realizados
principalmente pelas Unidades Básicas de Saúde
(UBS) (6,0%), seguidos de demanda espontânea
do usuário ao serviço (43,7%) (tabela 2). Foi expressiva a quantidade de usuários dos Tabela 2. Resultados Perfil dos clientes atendidos nos CAPSad, segundo tempo de tratamento, demanda pelo atendimento, formas de
encaminhamento, modalidade de tratamento e se houve internação. Triângulo Mineiro (MG), Brasil, 2016
Variáveis/Categorias
Distribuição
(n = 369)
%
Tempo de tratamento no CAPSad (em anos)
Menos de 1 ano
26
7,0
De 1 a 5 anos
232
62,9
De 5 a 10 anos
83
22,5
≥ 10 anos
28
7,6
Demanda pelo atendimento
Busca espontânea
161
43,7
Encaminhamento
165
44,7
Busca da família
8
2,2 Tabela 2. Perfil dos clientes atendidos nos CAPSad, segundo tempo de tratamento, demanda pelo atendimento, formas de
encaminhamento, modalidade de tratamento e se houve internação. Triângulo Mineiro (MG), Brasil, 2016
Variáveis/Categorias
Distribuição
(n = 369)
%
Tempo de tratamento no CAPSad (em anos)
Menos de 1 ano
26
7,0
De 1 a 5 anos
232
62,9
De 5 a 10 anos
83
22,5
≥ 10 anos
28
7,6
Demanda pelo atendimento
Busca espontânea
161
43,7
Encaminhamento
165
44,7
Busca da família
8
2,2 SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 Centros de Atenção Psicossocial – álcool e drogas: perfil dos usuários 455 Tabela 2. (cont.)
Busca de amigos
2
0,5
Ordem judicial
3
0,8
Trabalho
1
0,3
Não informado
29
7,9
Formas de Encaminhamento
Unidade Básica de Saúde (UBS)
22
6,0
Programa de Saúde da Família (PSF)
10
2,7
Unidades de emergência
4
1,1
Centros de Referência de Assistência Social (Cras)
2
0,5
Grupos de apoio
1
0,3
Hospital psiquiátrico
20
5,4
Hospital geral
12
3,3
Ordem judicial
15
4,1
Outros
83
22,5
Não se aplica
170
46,1
Não informado
30
8,1
Internação por uso de substância psicoativa
Sim
147
39,8
Não
125
33,9
Não informado
97
26,3
Faz uso de medicação devido ao uso de substância psicoativa
Sim
239
64,8
Não
79
21,4
Não informado
51
13,8
Modalidade de atendimento no CAPSad
Intensivo
68
18,4
Semi-intensivo
225
61,0
Não intensivo
42
11,4
Não informado
34
9,2
Fonte: Banco de dados da pesquisa sobre o perfil dos clientes dos CAPSad da região do Triângulo Mineiro (MG), 2016. Internação por uso de substância psicoativa Não informado Não informado Modalidade de atendimento no CAPSad 0,5%), respectivamente. Apresenta, também, o
consumo no último mês, tendo como referên-
cia o momento do acolhimento no CAPSad. O
álcool foi a substância mais utilizada (77,8%); e
o LSD e o êxtase foram as menos (0% e 0,3%). Resultados A tabela 3 apresenta os tipos de drogas con-
sumidas durante a vida: 89,7% consumiram
álcool ao longo da vida, seguido pelo tabaco
(58,3%), enquanto as substâncias alucinógenas
e o LSD foram os menos consumidos (2,2% e SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 456 Trevisan ER, Castro SS Tabela 3. Drogas utilizadas durante a vida e no último mês pelos clientes dos CAPSad do Triângulo Mineiro (MG), Brasil,
2016 (N = 365)
Drogas utilizadas*
Uso na vida
Uso no mês
n
%
n
%
Tabaco
215
58,3
160
43,4
Álcool
331
89,7
287
77,8
Maconha
166
45,0
97
26,3
Cocaína
141
38,2
72
19,5
Crack
161
43,6
124
33,6
Anfetamina
9
2,4
4
1,1
Benzodiazepínico
11
3,0
5
1,4
Solvente
15
4,1
4
1,1
LSD
2
0,5
0
0
Alucinógenos
8
2,2
4
1,1
Êxtase
2
0,5
1
0,3
Outras
16
4,3
7
1,9
Fonte: Banco de dados da pesquisa sobre o perfil dos clientes dos CAPSad da região do Triângulo Mineiro (MG), 2016. * Não informaram (n= 4). Nota: Categorias não são mutuamente exclusivas bela 3. Drogas utilizadas durante a vida e no último mês pelos clientes dos CAPSad do Triângulo Mineiro (MG), Brasil,
016 (N = 365) rogas utilizadas durante a vida e no último mês pelos clientes dos CAPSad do Triângulo Mineiro (MG), Brasil,
365) (42,9%), e os que não possuíam utilizavam a
cocaína (71,0%). Considerando a situação de
trabalho, verificou-se que a droga mais con-
sumida pelas pessoas que possuíam ocupação
foi o álcool (44,7%), e a mais consumida pelos
que não possuíam ocupação foi o crack (64,0%)
(tabela 4). Verificou-se que a droga mais consumida
entre os homens foi o tabaco (81,3%), e entre
as mulheres foi o crack (22,6%). Com relação
à faixa etária, a droga mais consumida entre
os adultos (77,4%) e os idosos (83,8%) foi o
álcool. Os usuários dos CAPSad que possuí-
am companheiro(a) consumiam mais álcool Tabela 4. Drogas utilizadas no último mês, no momento do acolhimento nos CAPSad, segundo sexo, faixa etária, estado
civil e situação de trabalho. Triângulo Mineiro (MG), Brasil, 2016
Tipos de Drogas
Sexo (n=364) - Não informaram (n=5)
Homens (n=297 – 80,5%)
Mulheres (n=67 – 18,2%)
n
%
n
%
Tabaco
130
81,3
28
17,5
Álcool
232
80,9
50
17,4
Maconha
78
80,4
17
17,5
Cocaína
55
76,4
16
22,2
Crack
94
75,8
28
22,6 Tabela 4. Resultados Drogas utilizadas no último mês, no momento do acolhimento nos CAPSad, segundo sexo, faixa etária, estado
civil e situação de trabalho. Triângulo Mineiro (MG), Brasil, 2016 bela 4. Drogas utilizadas no último mês, no momento do acolhimento nos CAPSad, segundo sexo, faixa etária, estado
vil e situação de trabalho. Triângulo Mineiro (MG), Brasil, 2016 SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 457 Centros de Atenção Psicossocial – álcool e drogas: perfil dos usuários Tabela 4. (cont.)
Tipos de Drogas
Faixa etária (n=360) - Não informaram (n=9)
Adulto (n=323 – 87,5%)
Idoso (n=37 – 10,0%)
n
%
n
%
Tabaco
145
44,9
14
37,8
Álcool
250
77,4
31
83,8
Maconha
93
28,8
2
5,4
Cocaína
68
21,1
1
2,7
Crack
122
37,8
0
0,0
Tipos de Drogas
Possui companheiro(a) (n=341) - Não informaram (n=28)
Sim (n=118 – 32,0%)
Não (n=141 – 38,2%)
n
%
n
%
Tabaco
55
44,0
70
56,0
Álcool
95
45,7
113
54,3
Maconha
27
38,0
44
62,0
Cocaína
22
44,9
27
55,1
Crack
31
36,0
55
64,0
Fonte: Banco de dados da pesquisa sobre o perfil dos cientes dos CAPSad da região do Triângulo Mineiro (MG), 2016. Nota: Categorias não são mutuamente exclusivas. Discussões de idade dos clientes, obtiveram 35,2 anos
no município de Iguatu (CE) e 41,9 anos em
Campo Grande (MS)8,19. Os usuários dos CAPSad do Triângulo Mineiro
são predominantemente do sexo masculino,
assim como revelado por outras investigações
que avaliaram o perfil das populações aten-
didas nos CAPSad em diversos municípios e
regiões do País7-14. A maioria dos usuários dos CAPSad
não possuía companheiro(a). Esse resul-
tado também foi apresentado em outros
estudos9,11,20. Pessoas que fazem uso abusivo
de álcool e outras drogas têm maiores possibi-
lidades de passarem por abandonos conjugais
e separações. O isolamento social e a perda
de vínculos familiares prejudicam a busca e
a adesão ao tratamento. Já aqueles que ainda
possuem vínculo familiar, principalmente
filhos, têm maiores chances de iniciarem o
tratamento e terem sucesso21. Com relação a faixa etária, estado civil e
situação de trabalho, houve similaridade com
outros estudos8,9,12,13,15-18. O estudo de Faria e Schneider10, realizado
no CAPSad do município de Blumenau (SC),
apresentou as faixas etárias por segmentos,
sendo que os usuários com mais de 34 anos
eram a maioria em atendimento no serviço. Esse dado corrobora o de Freitas et al.16, que
indica a incidência de maiores taxas a partir
de 31 anos, referente ao CAPSad do município
de Picos (PI). Monteiro24 define a faixa etária
entre 19 e 59 anos (87,7%) como prevalente
no CAPSad de Teresina (PI). Os estudos que
demonstraram essa variável, a partir da média O contexto familiar é um aspecto impor-
tante, que deve ser considerado na abordagem
do uso de substâncias psicoativas. As relações
familiares podem funcionar como um fator de
proteção ou de risco para o comportamento
de consumir drogas22. A família é um fator
de proteção ao uso abusivo de drogas quando
oferece ambiente doméstico harmônico, estável SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 Trevisan ER, Castro SS 458 de vida e a condição financeira. Tal situação
causa uma desorganização da vida, levando
ao absenteísmo, a dificuldades em cumprir as
tarefas, à perda do emprego, ao descompromis-
so financeiro, à subvalorizacão da autoimagem
e à manutenção de sentimentos negativos pelas
perdas econômicas27. e seguro, com regras claras de conduta e envol-
vimento dos pais na vida dos filhos. Discussões Porém, pode
ser considerada um risco quando o ambiente
doméstico é desordenado, há consumo ou atitu-
des favoráveis com relação ao uso de drogas, pais
que não proporcionam suporte e apoio social,
ausência de monitoramento e expectativas altas
e irrealistas entre os membros23. A maioria dos clientes está em tratamento
no CAPSad de 1 a 5 anos. Houve um percentual
relevante de encaminhamentos ao CAPSad
por outros serviços. Outros estudos também
verificaram a demanda pelo atendimento do
CAPSad, com prevalência dos encaminhamen-
tos feitos por profissionais ou pelos serviços
de saúde9,13. Esse resultado reforça a hipótese
de que a atenção integral à saúde das pessoas
que fazem uso nocivo de álcool e outras drogas
está sendo constituída e articulada em rede,
um dos pressupostos da Raps. Ao verificar
que mais usuários estão sendo encaminhados
pela rede pública, supõe-se que as unidades
estejam mais integradas ao CAPSad, efetivando
o funcionamento da Raps. No tocante à escolaridade, o estudo de
Carvalho et al.8 demonstrou que 42,6% tinham
entre quatro e sete anos de estudo. Horta et
al.17 concluíram que 56,8% tinham até oito
anos de escolaridade. Demais estudos apontam
que: 71,0% dos usuários possuíam o ensino
fundamental completo16; e 40,0% ensino fun-
damental24. Esses resultados são semelhantes
ao que foi verificado nesta pesquisa. A baixa escolaridade da população investigada
corrobora os resultados disponíveis na literatura,
que sugere a relação entre a evasão escolar e o
uso de drogas. Essa relação pode ter ocorrido
não somente pelo uso de drogas, mas pelas con-
sequências que o uso acarreta aos indivíduos, tais
como dificuldades cognitivas e gerais de saúde25. Os CAPSad oferecem as seguintes modali-
dades de tratamento: intensivo, semi-intensivo
e não intensivo. O tratamento intensivo é di-
recionado às pessoas com grave sofrimento
psíquico, que precisam de atenção contínua e
diária. O semi-intensivo é oferecido às pessoas
que necessitam de atenção direta da equipe,
mas com melhor estruturação psíquica (o
usuário pode ser atendido até 12 dias no mês). Já o tratamento não intensivo é oferecido às
pessoas que não necessitam de suporte con-
tínuo, limitando-se o seu atendimento a até
três dias no mês. As atividades consistem em
atendimento individual, em grupo, oficinas
terapêuticas, visitas domiciliares, repouso e
desintoxicação ambulatorial3. A modalidade
mais utilizada foi a semi-intensiva, conforme
apresentado em outros estudos7,13,15,16. Discussões Com relação à situação de trabalho, a pre-
dominância de desemprego é a realidade de
muitos estudos sobre o perfil dessa popula-
ção18. Neste estudo, a taxa de desemprego foi
de 34,7%, muito próxima da observada em
estudo realizado por Monteiro et al.24, com
taxa de 35,70%. Em outras pesquisas que
apresentaram a variável ocupação, houve
predominância dos clientes que não possuíam
nenhum tipo de ocupação, cujas porcentagens
variaram de 51,5% a 87,3%7,17,19,24,26. Apesar de o
desemprego ser uma questão de ordem estru-
tural e conjuntural na realidade da população
estudada, ele torna-se mais significativo, visto
que este representa um segmento vulnerável
e marginalizado dentro do conjunto dos so-
cialmente excluídos9. Os resultados desta pesquisa evidencia-
ram, também, que a maioria dos usuários
dos CAPSad, onde o estudo se desenvolveu,
já esteve internada em hospitais ou clínicas
por uso de substâncias psicoativas. Dos três
CAPSad participantes da pesquisa, apesar de O consumo de álcool foi mais significativo
entre os usuários que tinham ocupação, e o uso
do crack entre as pessoas que não tinham. O
uso habitual, abusivo e constante das drogas
prejudica as relações sociais, familiares e de
trabalho do indivíduo, afetando a qualidade SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 459 Centros de Atenção Psicossocial – álcool e drogas: perfil dos usuários três CAPSad investigados realizava atendimentos
direcionados a essa população. dois serem registrados como CAPSad III –
24 horas, apenas um estava, efetivamente,
funcionando nesse formato, que disponibi-
liza o cuidado contínuo, fundamental para
o acompanhamento das situações de maior
complexidade e atenção à crise no território,
aprofundando as ações substitutivas ao modelo
de internação em hospitais e/ou clínicas es-
pecializadas. A carência dessa modalidade
de Caps fragiliza as ações de retaguarda e de
garantia de cuidados contínuos e de gestão
da crise no território de forma regionalizada. Trata-se, deste modo, de um ponto crítico para
responder de forma substitutiva às necessida-
des de internação. O conceito de redução de danos é preco-
nizado pela Política do Ministério da Saúde
para a Atenção Integral a Usuários de Álcool
e outras Drogas e propõe diretrizes que
colocam o usuário no papel de protagonista
de sua vida e do seu tratamento. O Ministério
da Saúde compreende, a partir dessa política,
que a abstinência não é o único caminho a ser
percorrido nem, necessariamente, deva ser o
ponto de partida no tratamento. Discussões Considerar as
singularidades de cada sujeito é fundamental
para as práticas de saúde, que devem consi-
derar a diversidade e envolver a participação
e o engajamento da pessoa em tratamento. A redução de danos é uma prática onde as
estratégias são construídas com os usuários,
com foco na liberdade, na corresponsabilida-
de e na capacidade do usuário de fazer suas
próprias escolhas3,36,37. O CAPSad III não tem por finalidade ofere-
cer estrutura hospitalar, mas ter recursos para
atuar de forma articulada na Raps quando for
necessário o cuidado intensivo, de 24 horas,
do usuário do serviço. A implementação desse
dispositivo como uma forma de reorganização
da rede de atenção tem mostrado resultados
satisfatórios, como a redução das internações
e do tempo de permanência dos usuários em
hospitais psiquiátricos, e também dos casos
de emergências relacionadas ao uso de álcool
e outras drogas que chegam às Unidades de
Pronto Atendimento28. Este estudo investigou, também, os tipos de
drogas consumidas pelos usuários dos CAPSad
durante a vida e no momento do acolhimento
no serviço. A substância mais consumida ao
longo da vida e no momento de acolhimento
foi o álcool, seguido pelo tabaco. Esses dados
encontram ressonância em estudos e levan-
tamentos feitos na população geral e na po-
pulação em tratamento decorrente do uso de
substâncias psicoativas7,9,10,16. A maioria dos clientes iniciou o uso de subs-
tâncias psicoativas na faixa etária entre 12 e 15
anos. Esse resultado está de acordo com outros
estudos que abordaram essa variável14,17,29,30. Os levantamentos epidemiológicos sobre o
consumo de álcool e outras drogas no mundo
e no Brasil mostram que é nessa fase do desen-
volvimento que se inicia o uso de substâncias
nocivas à saúde31-35. O período da adolescência
é marcado por intensas mudanças e adaptações
que o indivíduo vivencia na transição para a
fase adulta. É um período considerado crítico
no que se refere ao desenvolvimento de com-
petências pessoais e interpessoais, aquisição de
habilidades e tomada de decisões. Essa fase do
desenvolvimento constitui um período crucial
no ciclo vital para o início do uso de drogas, seja
como mera experimentação, seja como consumo
ocasional, indevido ou abusivo22. Apenas um dos Em 2015, as mortes relacionadas ao
consumo abusivo de álcool e dependência
de álcool no Brasil corresponderam a 93,5%
do total de óbitos por causa básica atribuída
ao uso de substâncias psicoativas38. Discussões O uso
abusivo do álcool é um dos fatores de risco
de maior impacto para a morbidade, morta-
lidade e incapacidades em todo o mundo, e,
segundo dados da OMS, está relacionado a 3,3
milhões de mortes a cada ano. Dessa forma,
quase 6% de todas as mortes em todo o mundo
são atribuídas total ou parcialmente ao álcool. No Brasil, o álcool esteve associado a 63% e
60% dos índices de cirrose hepática e a 18% e
5% dos acidentes de trânsito entre homens e
mulheres em 2012, respectivamente39. SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 460 Trevisan ER, Castro SS Entretanto, existem os interesses econômicos
sobre o consumo de bebidas alcoólicas no Brasil,
que estão relacionados, também, com o mercado
econômico, já que representa uma importante
receita. De acordo com os dados da Pesquisa de
Orçamentos Familiares (POF), realizada pelo
Instituto Brasileiro de Geografia e Estatística –
IBGE (2008-2009), que investigou o consumo de
alimentos e outros produtos a partir dos gastos
familiares, houve aumento no consumo, nos
últimos 40 anos, num ritmo médio de 2,5% ao
ano. As despesas com bebidas alcoólicas têm
maior participação nos gastos familiares mensais
à medida que aumenta a renda familiar. Também
é maior nas áreas urbanas, com maior participa-
ção relativa de outros tipos de bebidas diferentes
de cervejas e chopes40. de intervenções focadas na realidade e nas
demandas dessa população. A atenção psicos-
social realizada nos CAPSad deve ser constan-
temente avaliada em um contínuo processo
de pensar as práticas e recriá-las, a fim de
aprimorar as ações, ampliando as atividades
clínicas em busca de atender às necessidades. O perfil da maioria dos usuários dos
CAPSad onde o estudo foi realizado
foi de homens, entre 41 e 60 anos, sem
companheiro(a) e desempregados. Esse
panorama reforça a necessidade de resgatar
a autonomia desses sujeitos, proporcionan-
do sua reinserção na comunidade, através
do trabalho com valor social, da busca dos
direitos de cidadania a partir de uma as-
sistência especializada, individualizada e
que traga melhoria da qualidade de vida
dessa população e de seus familiares. As
redes sociais de apoio, a intersetorialidade
e a articulação da Raps devem ser a base de
sustentação para que essas questões passem
do discurso e se concretizem na prática. Colaboradores Trevisan ER (0000-0002-3015-1630)* con-
tribuiu para a concepção, o planejamento, a
análise e a interpretação dos dados; revisão
crítica do conteúdo; e aprovação da versão final
do manuscrito. Castro SS (0000-0002-0005-
7555)* contribuiu para a análise e a interpre-
tação dos dados; revisão crítica do conteúdo
e a aprovação da versão final do manuscrito.s Discussões As estratégias para a diminuição do consumo
abusivo de álcool são fundamentais para minimi-
zar os impactos na saúde, nos âmbitos individual
e coletivo, incluindo a redução da sobrecarga no
sistema de saúde devido a agravos relacionados
ao consumo abusivo de álcool. Entre as medidas
recomendadas pela OMS, o aumento dos preços
das bebidas alcoólicas é uma forma efetiva para a
redução do consumo abusivo de álcool, o controle
rígido sobre o acesso a bebidas alcoólicas, incluin-
do a restrição do horário para a venda e maior
regulação e restrição dos pontos de venda38. Procedimentos que estejam em consonância
com os preceitos da Raps, com práticas interse-
toriais disponíveis na comunidade, desenvolvi-
mento de projetos de promoção da saúde física
e mental, programas de redução de danos, ela-
boração de programas de cooperativas sociais de
trabalho e inclusão social, podem ser importantes
estratégias para a diminuição do consumo do
álcool e para minimizar os impactos na saúde
nos âmbitos individual e coletivo. Uma limitação do estudo se dá com relação
aos dados coletados a partir de informações
produzidas pelos próprios serviços e registra-
das nos prontuários. Houve um índice de dados
não preenchidos nos prontuários dos clientes
dos três CAPSad. O registro das informações
das instituições públicas de saúde deve ser feito
corretamente, para possibilitar as análises epi-
demiológicas e viabilizar fontes fidedignas para
pesquisas científicas. *Orcid (Open Researcher
and Contributor ID). Referências 10. Faria JG, Schneider DR. O perfil dos usuários do
CAPSad-Blumenau e as políticas públicas em saúde
mental. Psicol. soc. 2009; 21(3):324-333. 1. Amarante P, Nunes MO. A reforma psiquiátrica no
SUS e a luta por uma sociedade sem manicômios. Ciênc. Saúde Colet. 2018; 23:2067-2074. 2. Trevisan ER, Castro SS. Aspectos psicossociais do
trabalho em Saúde Mental: uma revisão integrativa. SMAD Rev Eletrônica Saúde Ment. Álcool e Drog. 2016; 12(3):188-197. 11. Marini M. Preditores de adesão ao projeto terapêuti-
co em centro de atenção psicossocial álcool e outras
drogas [dissertação] [internet]. Porto Alegre: Univer-
sidade Federal do Rio Grande do Norte, Escola de En-
fermagem; 2011 [acesso em 2015 mar 31]. Disponível
em: http://www.lume.ufrgs.br/handle/10183/36963. 3. Brasil. Ministério da saúde. A política do Ministério
da Saúde para a atenção integral a usuários de álcool
e outras drogas [internet]. Brasília, DF: Ministério da
Saúde; 2003. [acesso em 2019 jul 4]. Disponível em:
http://bvsms.saude.gov.br/bvs/publicacoes/pns_al-
cool_drogas.pdf. 3. Brasil. Ministério da saúde. A política do Ministério
da Saúde para a atenção integral a usuários de álcool
e outras drogas [internet]. Brasília, DF: Ministério da
Saúde; 2003. [acesso em 2019 jul 4]. Disponível em:
http://bvsms.saude.gov.br/bvs/publicacoes/pns_al-
cool_drogas.pdf. 12. Pelisoli CL, Moreira ÂK. Epidemiological characte-
rization of the users of Casa Aberta, a psychosocial
attention center. Rev. psiquiatr. Rio Gd. Sul. 2005;
27(3):270-277. 13. Pelisoli CL, Moreira ÂK. Avaliação de um centro de
atenção psicossocial por meio do perfil de seus usu-
ários. Mental. 2007; 5(8):61-75. 4. Oliveira MAF, Cestari TY, Pereira MO, et al. Processos
de avaliação de serviços de saúde mental: uma revi-
são integrativa da literatura. Saúde debate [internet]. 2014 [acesso em 2015 maio 19]; 38(101). Disponível
em: http://www.scielo.br/pdf/sdeb/v38n101/0103-
1104-sdeb-38-101-0368.pdf. 14. Pereira MO, Souza JM, Costa ÂM, et al. Perfil dos
usuários de serviços de saúde mental do municí-
pio de Lorena-São Paulo. Acta Paul. Enferm. 2012;
25(1):48-54. 5. World Health Organization. World drug report 2016. Genebra: United Nations Pubns; 2016. 15. Freitas AA, Souza RC. Caracterização clínica e so-
ciodemográfica dos usuários de um centro de aten-
ção psicossocial (CAPS). Rev. baiana saúde pública. 2010; 34(3):100-233. 6. Claro HG, Oliveira MAF, Bourdreaux JT, et al. Drug
use, mental health and problems related to crime and
violence: cross-sectional study. Rev. Latino-Am. En-
fermagem. 2015; 23(6):1173-1180. 16. Freitas RM , Silva HRR , Araújo DS. Resultados do
acompanhamento dos usuários do Centro de Atenção
Psicossocial - Álcool e Drogas (Caps-AD). SMAD Rev
Eletrônica Saúde Ment. Conclusões O conhecimento do perfil das pessoas atendi-
das nos CAPSad permite o desenvolvimento SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 461 Centros de Atenção Psicossocial – álcool e drogas: perfil dos usuários Referências Álcool e Drog. 2012; 8(2):56-
63. 7. Almeida RA, Anjos UU, Vianna RP T, et al. Profile
of users of psychoactive substances in João Pessoa. Saúde debate. 2014; 38(102):526-538. 8. Carvalho MDA , Silva HO, Rodrigues LV. Perfil epi-
demiológico dos usuários da Rede de Saúde Mental
do Município de Iguatu, CE. SMAD Rev Eletrônica
Saúde Ment. Álcool e Drog. 2010; 6(2):337-349. 17. Horta RL, Horta BL, Rosset AP. Perfil dos usuá-
rios de crack que buscam atendimento em Centros
de Atenção Psicossocial. Cad. Saúde Pública. 2011;
27(11):2263-2270. 9. Constantino P, Batista LSS. Batista M. Perfil dos usu-
ários de substâncias psicoativas do caps ad em 2000
e 2009, Campos dos Goytacazes, RJ. Persp. online:
biol & saúde. 2012; 7(2):23-38. 18. Jorge JS, Corradi-Webster CM. Consultório de Rua:
contribuições e desafios de uma prática em constru-
ção. Sau. & Transf. Soc. 2012; 3(1):39-48. SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 Trevisan ER, Castro SS 462 se e caracterização. Rev. bras. enferm. 2018; 71:2251-
2257. 19. Peixoto C, Prado CHO, Rodrigues CP, et al. Impact
of clinical and socio-demographic profiles in treat-
ment adherence of patients attending a day hospital
for alcohol and drug abuse. J. bras. psiquiatr. 2010;
59(4):317-321. 29. Figlie NB, Bordin S, Laranjeira R. Aconselhamen-
to em Dependência Química. 2. ed. São Paulo: Roca;
2010. 20. Rocha WS, Alves ERP, Vieira KFL, et al. Concepções
dos usuários de crack sobre os fatores que influen-
ciam o uso e a dependência. SMAD Ver. Eletrônica
Saúde Ment. Álcool e Drog. 2015; 11(3):129-135. 30. Lopes AP, Rezende MM. Consumo de substâncias
psicoativas em estudantes do ensino médio. Psicol. teor. prát. 2014; 16(2):29-40. 21. Almeida CS, Luis MAV. Características sociodemo-
gráficas e padrão de uso de crack e outras drogas em
um Caps. Rev. enferm. UFPE on line. 2017; 11(4):1716-
1723. 31. Domingos NAM, Domingos JCV. Levantamento so-
bre o uso de álcool e drogas em universitários. Rev. bras. ter. cogn. 2005; 1(1):75-82. 32. Galduróz JCF, Noto AR, Nappo SA, et al. Uso de dro-
gas psicotrópicas no Brasil: pesquisa domiciliar en-
volvendo as 107 maiores cidades do país-2001. Rev. Lat. Am. Enfermagem. 2005; 13(1):888-895. 22. Schenker M, Minayo MCS. Risk and protective fac-
tors and drug use among adolescence. Ciênc. Saúde
Colet. 2005; 10(3):707-17. 23. Ribeiro M, Dualibi L. Avaliação de fatores de prote-
ção e de risco. In: Laranjeira R, organizador. Referências O tra-
tamento do usuário de crack. São Paulo: Casa Leitu-
ra Médica; 2010. p. 175-86. 33. Laranjeira R, Madruga CS, Pinsky I, et al. II levanta-
mento nacional de álcool e drogas [internet]. São Pau-
lo: Instituto Nacional de Ciência e Tecnologia para
Políticas Públicas do Álcool e Outras Drogas; 2013. [acesso em 2019 jun 30]. Disponível em: http://inpad. org.br/wp-content/uploads/2013/04/LENAD_Pres-
sRelease_Alcohol_RVW.pdf. 24. Monteiro CFS, Fé LCM, Moreira MAC, et al. Perfil
sociodemográfico e adesão ao tratamento de depen-
dentes de álcool em CAPS-ad do Piauí. Esc. Anna
Nery Rev. Enferm. 2011; 15(1):90-95. 34. Pratta EMM, Santos MA. Levantamento dos motivos
e dos responsáveis pelo primeiro contato de adoles-
centes do ensino médio com substâncias psicoativas. SMAD Rev. Eletrônica Saúde Ment. Álcool E Drog. 2006; 2(2):1-17. 25. Araujo NB, Marcon SR, Silva NG. Clinical and socio-
demographic profile of adolescents who stayed and
did not stay in treatment at CAPSad Cuiabá/MT. J. bras. psiquiatr. 2012; 61(4):227-234. 35. Silveira DX. Reflexões sobre a prevenção do uso
indevido de drogas. In: Silveira DX, Niel M, orga-
nizadores. Drogas e redução de danos: uma carti-
lha para profissionais de saúde [internet]. São Pau-
lo; 2008 [acesso em 2015 ago 14]. Disponível em:
http://www.researchgate.net/profile/Dartiu_Sil-
veira/publication/230824010_Drogas_e_reduo_de_
danos_uma_cartilha_para_profissionais_de_sade/
links/09e41509165f4641c3000000.pdf#page=7. 26. Hess ARB, Almeida RMM, Moraes AL. Comorbida-
des psiquiátricas em dependentes químicos em abs-
tinência em ambiente protegido. Estud. Psicol. 2012;
17(1):171-178. 27. Nimtz MA, Tavares AMF, Maftum MA, et al. Impac-
tos legais e no trabalho na vida do dependente quí-
mico. SMAD Rev. Eletrônica Saúde Ment. Álcool e
Drog. 2016; 12(2):68-74. 36. Brasil. Ministério da Saúde, Secretaria de Atenção à
Saúde. Reforma psiquiátrica e política de saúde mental
no Brasil. Brasília, DF: OPAS; 2005. [acesso em 2019 36. Brasil. Ministério da Saúde, Secretaria de Atenção à
Saúde. Reforma psiquiátrica e política de saúde mental
no Brasil. Brasília, DF: OPAS; 2005. [acesso em 2019 28. Boska GA, Oliveira MAF, Claro HG, et al. Leitos em
centro de atenção psicossocial álcool e drogas: análi- SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019 463 Centros de Atenção Psicossocial – álcool e drogas: perfil dos usuários 39. World Health Organization. Global status report on
alcohol and health, 2014. Geneva: World Health Or-
ganization; 2014. jun 30]. Disponível em: http://bvsms.saude.gov.br/
bvs/publicacoes/Relatorio15_anos_Caracas.pdf. jun 30]. Disponível em: http://bvsms.saude.gov.br/
bvs/publicacoes/Relatorio15_anos_Caracas.pdf. 37. Calassa GDB, Penso MA, Freitas LG. Referências Redução de danos
na visão dos profisssionais que atuam no CAPS AD II
do Distrito Federal. Psicol. pesq. 2015; 9(2):177-187. 40. Yamamoto CH. A demanda por bebidas alcoólicas
no Brasil: 2008/2009 [dissertação]. São Paulo: Fun-
dação Getúlio Vargas; 2011. 38. Munhoz TN, Santos IS, Nunes BP, et al. Tendências de
consumo abusivo de álcool nas capitais brasileiras en-
tre os anos de 2006 a 2013: análise das informações do
Vigitel. Cad. Saúde Pública [internet]. 2017 [acesso em
2017 out 24]; 33(7):1-11. Disponível em: http://www.scie-
lo.br/scielo.php?script=sci_arttext&pid=S0102-311X20
17000705011&lng=pt&tlng=pt. SAÚDE DEBATE | RIO DE JANEIRO, V. 43, N. 121, P. 450-463, ABR-JUN, 2019
|
https://openalex.org/W3037045021
|
http://nrl.northumbria.ac.uk/id/eprint/43612/9/Advance%20online%20version.pdf
|
English
| null |
Tacit domains: The transference of practitioner know‐how in contemporary English planning practice
|
Area
| 2,020
|
cc-by
| 6,931
|
Published by: Wiley-Blackwell URL: https://doi.org/10.1111/area.12641 <https://doi.org/10.1111/area.12641> This
version
was
downloaded
from
Northumbria
Research
Link:
http://nrl.northumbria.ac.uk/id/eprint/43612/ This
version
was
downloaded
from
Northumbria
Research
Link:
http://nrl.northumbria.ac.uk/id/eprint/43612/ This
version
was
downloaded
from
Northumbria
Research
Link:
http://nrl.northumbria.ac.uk/id/eprint/43612/ Northumbria University has developed Northumbria Research Link (NRL) to enable users
to access the University’s research output. Copyright © and moral rights for items on
NRL are retained by the individual author(s) and/or other copyright owners. Single copies
of full items can be reproduced, displayed or performed, and given to third parties in any
format or medium for personal research or study, educational, or not-for-profit purposes
without prior permission or charge, provided the authors, title and full bibliographic
details are given, as well as a hyperlink and/or URL to the original metadata page. The
content must not be changed in any way. Full items must not be sold commercially in any
format or medium without formal permission of the copyright holder. The full policy is
available online: http://nrl.northumbria.ac.uk/policies.html This document may differ from the final, published version of the research and has been
made available online in accordance with publisher policies. To read and/or cite from the
published version of the research, please visit the publisher’s website (a subscription
may be required.) Northumbria Research Link Citation: Muldoon-Smith, Kevin and Mcguinness, David (2022) Tacit Domains: The
Transference of Practitioner Know‐How in Contemporary English Planning Practice. Area,
54 (3). pp. 501-508. ISSN 0004-0894 Published by: Wiley-Blackwell Area. 2021;00:1–8. Kevin Muldoon-Smith1
| David McGuinness2 1Northumbria University, Newcastle-
upon-Tyne, UK
2Architecture and Built Environment,
Northumbria University, Newcastle-
upon-Tyne, UK 1Northumbria University, Newcastle-
upon-Tyne, UK | 1
wileyonlinelibrary.com/journal/area Tacit domains: The transference of practitioner know-how
in contemporary English planning practice Kevin Muldoon-Smith1
| David McGuinness2 S P E C I A L S E C T I O N S P E C I A L S E C T I O N This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided
the original work is properly cited.
The information, practices and views in this article are those of the authors and do not necessarily reflect the opinion of the Royal Geographical Society (with IBG).
© 2020 The Authors. Area published by John Wiley & Sons Ltd on behalf of Royal Geographical Society (with the Institute of British Geographers). Received: 29 August 2018 | Revised: 27 February 2020 | Accepted: 27 April 2020 Received: 29 August 2018 | Revised: 27 February 2020 | Accepted: 27 April 2020
DOI: 10.1111/area.12641 DOI: 10.1111/area.12641 Abstract Abstract
This paper reflects on ideas of tacit knowledge in order to examine the nature of
planners’ expertise. It investigates the shifting knowledge and power dynamics
between and within the public and private sectors, as a means of determining
how tacit expertise is transferred and re-appropriated in new domains and geog-
raphies of practice. Tacit understanding of what facilitates successful permissions
and what impedes the approval process helps planners navigate the plan-led sys-
tem and avoid inertia. Findings are two-fold. First, public sector planners transfer
their own expert tacit knowledge to influence and direct local development plan-
ning. Second, the findings illustrate that public sector planners feel their tacit
expertise is increasingly undervalued and traditional networks of knowledge
transference have been dismantled due to the erosion of networks of peer sup-
port. This results in a disruptive counter narrative based in private planning prac-
tice where public sector experts are re-emerging in commercial practice due to a
range of factors, including: budgets cuts; demoralisation; and seeking greater job
security in the private sector. This leads to new geographies of tacit knowledge, as
local government planners transfer their knowledge into new professional envi-
ronments. This can result in reconfigurations of locally embedded knowledge as
expertise is repurposed and used to bolster the likelihood of development appli-
cations succeeding, often for profit motives rather than the broader public good. Furthermore, it can also lead to local knowledge being uprooted and spatially dif-
fused across wider geographies as private sector planners frequently work across
broader domains of practice than public sector counterparts. In conclusion, we
outline gaps in our current understanding of the evolution of planning practice
and outline future research opportunities. 2Architecture and Built Environment,
Northumbria University, Newcastle-
upon-Tyne, UK 2Architecture and Built Environment,
Northumbria University, Newcastle-
upon-Tyne, UK Correspondence
Kevin Muldoon-Smith
Email: k.muldoon-smith@
northumbria.ac.uk 2 |
1 | INTRODUCTION AND METHODOLOGY The aim of this paper is to reflect on ideas of tacit knowledge in order to examine the nature of planners' expertise. It in-
vestigates the shifting knowledge and power dynamics between and within the public and private sectors to help under-
stand how tacit expertise is transferred and re-appropriated in new domains and geographies of practice as local planners
move to new local authorities in different locations or join private consultancies that have wider geographical remits. This focus is important because this transference has the potential to restructure the persistently local planning process
through a new politics of expertise. However, it also has the opportunity to deterritorialise traditionally local knowledge
and reposition it in different contexts beyond its original zone of creation – creating a new, more diffuse, geographical as-
semblage of planning knowledge. The paper addresses the overall research aim with two underlying research questions: 1. What is the value of local government tacit knowledge in contemporary planning practice? 1. What is the value of local government tacit knowledge in contemporary planning practice? l
l
l
k
l d
l
d
f
d
d
f
d
d 2. How is local government tacit planning knowledge valued, transferred, and 2. How is local government tacit planning knowledge valued, transferred, and reconfigured in new domains of practice? 2. How is local government tacit planning knowledge valued, transferred, and reconfigured i The empirical material in this paper is based on 20 semi-structured elite interviews (Temenos & McCann, 2013) in-
vestigating the issue of tacit knowledge and the trajectory of its diffusion between domains. The research was conducted
during 2017 with planning practitioners operating in senior positions within both the public (70%) and private sector
(30%). The authors initially targeted senior planners and then used a snowball approach to expand the sample through
local authority and Royal Town Planning Institute (RTPI) networks. Although a relatively small sample, this method-
ological approach generated a unique sample of responses from experienced practitioners across a comprehensive ge-
ography. The authors intentionally avoided Freedom of Information requests because of the likelihood of legalistic and
sanitised responses, which are unlikely to reflect uncodified tacit knowledge. While there is clearly an imbalance in
numbers between public and private side planning, the aim of the research is to understand the transference of planning
knowledge into private practice. 2 |
1 | INTRODUCTION AND METHODOLOGY All of the respondents were senior professionals with enough experience and seniority
to provide an overview of the movement of knowledge between both domains. A minimum of two respondents were
targeted in each of the eight former standard planning regions in England, to provide balanced geographic coverage. All
respondents had in excess of 15 years’ experience in planning roles, either development management, strategic planning,
and/or consultancy. The majority of the interviews were conducted face to face, a small number were conducted via
telephone, and all were recorded, transcribed, and then coded using an analysis matrix. A selection of quotes are utilised
within the latter half of the paper to elucidate key themes from these practitioners. The remainder of the paper considers the academic context for the research and sets out a conceptual framework for
the paper. It then analyses the empirical material and discusses the major findings before reflecting on the underlying
research questions and contemplating their implications for the evolution of planning theory and practice. The overall
conclusion is that conditions of austerity and changing governmental ideology have led to an evolving knowledge/power
dynamic that has the potential to disrupt and reconfigure the collaborative power relations underpinning local planning
practice in England. K E Y W O R D S expertise, knowledge, planning, power, public/private, tacit knowledge This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided
the original work is properly cited. The information, practices and views in this article are those of the authors and do not necessarily reflect the opinion of the Royal Geographical Society (with IBG). © 2020 The Authors. Area published by John Wiley & Sons Ltd on behalf of Royal Geographical Society (with the Institute of British Geographers). g
p
p
y
The information, practices and views in this article are those of the authors and do not necessarily reflect the opinion of the Royal Geographical Society (with IBG). © 2020 The Authors. Area published by John Wiley & Sons Ltd on behalf of Royal Geographical Society (with the Institute of British Geographers). MULDOON-SMITH and McGUINNESS 3 | CONCEPTUAL FRAMEWORK Polanyi (1958) introduced the idea of tacit knowledge, arguing that we can know more than we can tell. His assertion was
that expertise is deeply personal and difficult to communicate verbally or in writing and was more reliant on intuition. Tacit knowledge has been described as ‘know-how’ as opposed to ‘know-that’ (facts). In this sense, there is no distinc-
tion between expert knowledge and tacit knowledge as both are interconnected. Lundvall and Johnson (1994) and Zook
(2004) expanded Polanyi's dichotomy in the following way: • Know – what (broad knowledge about facts which is similar to information) • Know – why (an understanding of scientific principles) • Know – how (context-specific expertise) • Know – who (the density and strength of social networks) This latter treatment of tacit knowledge forms the conceptual framework for this paper. The first two categories are
analogous to Polanyi’s (1958) explicit fact-based knowledge while the latter categories relate to implicit tacit knowledge This latter treatment of tacit knowledge forms the conceptual framework for this paper. The first two categories are
analogous to Polanyi’s (1958) explicit fact-based knowledge while the latter categories relate to implicit tacit knowledge
– its context-specific base and the importance of networks in transferring and reconfiguring tacit knowledge. In this paper, tacit knowledge (often generated over decades) helps planners, and their communities of practice, influ-
ence and mediate within the development process. During their careers, planners accumulate expert tacit knowledge in
relation to their material local domains and institutional practice. However, this facilitating role is also one of privilege,
giving local government planners access to uncodified knowledge, or to use Beauregard’s (2005) terminology, ‘thick’
understanding of individual places. Illustrating this situation, subsequent sections of this paper will argue that, once gen-
erated, this knowledge can be mobilised and transferred into new place-based assemblages of knowledge and expertise
depending on the eventual domain of the planner (e.g., between public and private). As planners are vital stakeholders in the development process, their deep knowledge of local areas can be a desirable
asset for private sector planning consultancies. This is not a new phenomenon: public sector planners have been moving
into private practice for decades and vice versa. This process has enriched the planning discipline through a fluid circula-
tion of ideas. However, there are signs of an accelerated unidirectional movement, from local government planning into
private practices. 2 | LITERATURE REVIEW Within urban planning, the expertise of the professional masterplanners and the all-seeing gaze of unitary planning
regimes have been contested for decades (Sager, 1994). For example, building on relational concepts of space and place
(Massey, 2005) and communicative action (Habermas, 1981), the traditional role of the expert planner was destabilised
through the communicative planning turn (Booher & Innes, 2002; Healey, 1992). This placed collaborative planning
and, through critical debate, multi-scalar geometries of power, networks of activity, and contested decision-making and
outcomes (Innes & Booher, 2014; Tewdwr-Jones & Allmendinger, 1998) at the centre of what came to be known as col-
laborative, communicative, and post-positivistic planning. However, within academia there has been less emphasis on the mobility, structuring influence, and emerging geogra-
phies of planning knowledge. Although, it must be noted, there is some evidence of research in the knowledge expansion
domain (Perl & White, 2002), regulatory capitalism (Levi-Faur, 2009; Raco, 2014), and the politics of planning expertise
(Linovski, 2016). Nonetheless, analysis of how planning knowledge is acquired, developed, and mobilised within and be-
tween organisations and how this then influences local planning policy is less frequent. Therefore, rather than focusing
on the sanctity of knowledge and expertise per se, or the relatively well-researched geographies of policy mobility (Peck MULDOON-SMITH and McGUINNESS 3 & Theodore, 2015), the authors focus on the generation, transference, and mobility of planning knowledge into new do-
mains. In this case, from the public to the private sector consultancy planning domain. & Theodore, 2015), the authors focus on the generation, transference, and mobility of planning knowledge into new do-
mains. In this case, from the public to the private sector consultancy planning domain. In doing so, the paper contributes to the arguments of Dear (1989) in relation to the privatisation of planning prac-
tice, Steele (2009) in relation to the hybridisation of planners, and Parker et al. (2014), Raco et al. (2016), and Linovski
(2018) who attest that there is still relatively little known about the increasing role of private interests and consultants in
contemporary planning practice. More recently, Clifford (2019) has also charted the growing involvement of private com-
panies in delivering planning services for local authorities through a Freedom of Information research project. However,
this research largely looks at the role of private companies coming into local planning authorities (LPAs) to provide sup-
port or relatively rare outsourcing arrangements. 2 | LITERATURE REVIEW Indeed, Clifford’s (2019) findings suggest that the majority of this assis-
tance is technical support, application validation, and evidence gathering. Experienced LPA officers typically still carry
out policy development and final decisions. In contrast, this research looks at a different dimension of this situation, that
of the movement of experience-based knowledge out of LPAs into private practice. Initially, the authors approach this knowledge transfer through the work of Polanyi (1958) into codified and tacit
knowledge. They then utilise the contemporary work of Lundvall and Johnson (1994), Zook (2004), Fischler (2000), and
Hackling and Flynn (2017) who expand Polanyi's simple dichotomy into a more complex typology connected to shifting
networks of influence and the consequent politics of knowledge and power. The authors adopt this approach in order to
understand how relatively stable notions of collaborative planning at the local scale – traditionally facilitated by public
sector planners – are being destabilised and transformed into new organisational and geographical assemblages when
local government planners move into new domains of influence in private consultancy. 4 | THE TACIT DIMENSION: WHAT IS THE VALUE OF LOCAL GOVERNMENT
TACIT KNOWLEDGE IN CONTEMPORARY PLANNING PRACTICE? This section reflects on the first research question: what is the value of tacit knowledge in contemporary planning prac-
tice? The principle finding from all respondents is that place-based implicit knowledge is the foundation for effective
local plan-making and the consequent management of development. Local government planners collaborate with stake-
holder groups (within the public, private, and third sector) and channel this information into the development of local
planning strategies. There was an acknowledgment from respondents that this puts local government planners in privi-
leged positions as arbiters of local knowledge. Reflecting this situation, a planner with significant experience in both
the public and private sector, currently working as a national planning consultant, encapsulated the importance of tacit
knowledge to successful planning practice. He stated: I relate tacit knowledge to the connection between things built up over the years using the analogy of Chess
Grandmasters, … possessing an extensive understanding of connections – ‘if you do this you can expect this
range of responses – and if you act on them in this way you are likely in turn to get this further range of re-
sponses, etc.’ (Planning consultant/former LPA Chief Planner working across England) However, consensus was lacking among planners in England when questioned on their value as ‘place makers’ and the
transferability of their knowledge. I don’t think planners generally appreciate their own value – and the exceptional value of their ‘holistic’
discipline. (London-based planning consultant, working across England) There was also a growing degree of ethical concern among public sector respondents, that, due to the importance
of tacit knowledge being transmitted via networks, individuals could act as ‘gatekeepers’, as planners wield power
through their unique understanding of local planning contexts. Ultimately, this raises the possibility of tacit knowl-
edge being utilised in a negative sense to circumvent the wishes of the local community and force through devel-
opment. In this case, the gatekeeper can be seen to have potential market advantage. However, even private sector
respondents reported greater concern with the ethics of this situation rather than the commercial benefits for the
private organisation. Despite respondents viewing tacit knowledge as significant in the planning process, respondents within the pub-
lic sector emphasised that ‘knowledge’ was not a match for private sector ‘financial muscle’. 4 | MULDOON-SMITH and McGUINNESS The English plan-led system requires developers to submit a planning application, which is then assessed via discre-
tionary scrutiny at the local level based on individual consideration of site-specific material planning considerations. Consequently, in the English context, tacit knowledge of how the local plan has been developed, what the implicit mean-
ings are within the text of the plan, and how much latitude planners allow in considering ‘local circumstances’ is valuable
to the private sector. This tacit knowledge can lubricate the development management process, circumventing some of
the uncertainty within the system. The next section reflects on this situation in England. It considers how the develop-
ment plan process is being reconfigured at the local scale, the role that knowledge plays in this negotiation, and how
planning knowledge is evolving and being repositioned in new locations. 3 | CONCEPTUAL FRAMEWORK Edgar (2019) noted that while the total number of planners in England has grown slightly since 2010,
there has been a decrease in the percentage of (all) planners being employed in the public sector from 70 per cent in 2006
to 56 per cent in 2018 (Edgar, 2019). This generates potential for a tacit deficit in local government planning and the loss
of decades of knowledge. This repositioning of knowledge and power within contemporary planning practice forms the
interrogative context for the empirical material in the remainder of this paper. | 5 Once developers see the council doesn’t have up-to-date figures (e.g. a 5-year2 land supply) and it is going to
take 3 years to achieve an adopted plan … you are wide open to appeal … no amount of tacit knowledge can
help you then. (Private sector consultant/formerly Senior LPA Planner, Yorkshire) Once developers see the council doesn’t have up-to-date figures (e.g. a 5-year2 land supply) and it is going to
take 3 years to achieve an adopted plan … you are wide open to appeal … no amount of tacit knowledge can
help you then. (Private sector consultant/formerly Senior LPA Planner, Yorkshire) This substantiates Lord and Twedwr-Jones' (2018) assertion of a coordinated neoliberal ideological push to deregulate
planning. The injection of levers of policy centralisation and deregulation have co-existed with a period of stigmatising plan-
ners as obstructive bureaucrats. Coupled with austerity cuts, this has led to one third of local government planners in England
leaving the public sector (RTPI, 2015). In the next sections, the authors outline that some local government planners have
moved into private sector consultancy in search of new careers. In this evolving environment, gatekeepers of local knowledge
now combine with ‘financial muscle’ and can seek to manipulate, and in some instances circumvent, the local planning pro-
cess on behalf of private interests. 5 | TRANSFERRING KNOWLEDGE: HOW IS LOCAL GOVERNMENT
TACIT PLANNING KNOWLEDGE VALUED, TRANSFERRED, AND
RECONFIGURED IN NEW DOMAINS OF PRACTICE? Public sector planners have been vilified by national politicians (Lord & Twedwr-Jones, 2018), starved of financial re-
sources, and placed under increasing demands. Subsequently, for many demoralised practitioners the temptation to
leave the public sector has become irresistible: There is a perception that the more able planners have joined consultancies … the less able stayed … and are
deeply demoralised. (Private sector planner, London) 4 | THE TACIT DIMENSION: WHAT IS THE VALUE OF LOCAL GOVERNMENT
TACIT KNOWLEDGE IN CONTEMPORARY PLANNING PRACTICE? This asymmetrical power
dynamic has become more pronounced in the post-2012 National Planning Policy Framework (NPPF) era due to the
‘presumption in favour of sustainable development’1 which increases the likelihood of planning applications being deter-
mined via appeal. An emphasis on planning by appeal significantly favours developers during crippling austerity when
LPAs cannot repeatedly risk losing and being liable to pay substantial compensation to appellants. Respondents in the
Midlands and Yorkshire indicate this situation, It is important to foster good working relationships between the public and private sectors, which allow tacit
knowledge to be fed into the planning process … but this must be transparent … Ultimately, private sector
resources are such that tacit knowledge will only go so far. (LPA Planner, Core City, Midlands) | 5
LDOON-SMITH and McGUINNESS
Once developers see the council doesn’t have up-to-date figures (e.g. a 5-year2 land supply) and it is going to
take 3 years to achieve an adopted plan … you are wide open to appeal … no amount of tacit knowledge can
help you then. (Private sector consultant/formerly Senior LPA Planner, Yorkshire) MULDOON-SMITH and McGUINNESS 6 | This point is important because the weaknesses in local planning are often hidden, context-specific, and only known to
those with local knowledge. Our respondents were very reluctant to identify specific cases where ‘insider’ knowledge had
proved crucial, but it was acknowledged throughout the study as an issue in the planning system. After a decade of austerity, the consequent erosion of public sector planning teams cannot be understated. Public
sector respondents noted growing time and resource constraints, increasing volumes of work, lack of specialist skills,
and stretching government targets, responses that align with Raco's (2018) analysis highlighting professional planning
bodies reporting low morale, overwork, and lack of resources among public sector planners. Cumulatively, these issues
have significantly affected the opportunity for remaining staff to engage in networking, training, and knowledge transfer,
restricting opportunities for staff development internally through mentoring from experienced colleagues (who have
often left the system) or via external networking. We have lost some ‘wise old heads’ due to redundancy, early retirement and people simply deciding that
they have had enough … that level of knowledge is very hard to replace. (LPA planner, Core City, Midlands) This implies place-based structures of knowledge are being disrupted and potentially eroded as planner's move from the
public to the private sector. Concurrently, knowledge originally generated at the local scale has the potential to be re-purposed
and employed in new locations as private sector planners often work over wider geographies. All respondents in this study revealed a growing process of public sector planners moving into the private sector
and subsequently influencing the local planning process on behalf of developers. However, in the paper's distinct focus
on knowledge transfer to private sector consultancy it is worth noting that the public–private binary is not static, nor
is it always one-way. Steele's (2009) seminal work in an Australian context introduces the potential for a ‘third space’
in planning between the public and private sector, via a form of hybridised planning. Parker et al. (2018) have recently
illustrated the fragmentary nature of contemporary planning practice with some LPAs buying in specialist planning
skills from the private sector. Our research did not find significant evidence of a widespread evolution of hybrid plan-
ning across England. A limited number of local authorities are outsourcing their statutory planning role and associated
staff to private companies. 6 | Under this arrangement, planning staff ‘TUPE’3 transfer into private employment in order to
deliver their previous public sector roles, providing an evolving example of the hybrid planner depicted by Steele (2009). A minority of organisations are also specifically positioning themselves to take on exclusively public sector contracts to
avoid conflicts of interest (see for example the not-for-profit Public Practice social enterprise organisation in the UK that
positions professionals in the public sector). However, our research indicated a different side to the hybridity argument
that has hitherto mostly focused on private companies carrying out work for LPAs and a certain coming together between
public and private. Instead, our research indicates a movement of tacit knowledge away from LPAs into private consul-
tancy. This does not necessarily reflect hybridity, rather a re-assemblage of previously constructed knowledge. As Linovski attests, A shadow agency of consultant planners, often headed by former city staff … now move fluidly between
public and private sector contracts … The end result is a seeming convergence of development and public
interests, mobilized through the work of professional consultants. (2018, p. 32) This generates an increasing void in terms of experience within the public sector. A point confirmed by senior planners in
the public sector who indicated that entire layers of senior management have left authorities due to moving into private con-
sultancy or retiring. Consequently, not only does the individual planner leave for new employment, they also take with them
an accumulation of uncodified community knowledge. This raises questions of power inequality and knowledge proprietary
as the individual planner is free to switch to the private sector, but in contrast the community has no control over the loss of
knowledge. The direct consequence of this is that inexperienced local government planners can be pitted against adversaries who
possess an unrivalled knowledge of the local plan and the wider evidence base that the LPA are attempting to defend. This implies a rescaling of the power dynamics within the politics of local planning, influenced by the transference of
tacit knowledge into new domains and utilised for divergent aims to those originally envisioned during co-creation with
local stakeholders (e.g., the public good). The NPPF is widely viewed as a ‘developer's charter’ which has undermined LPAs’ negotiating position against devel-
opers. Developers frequently commission planning consultancies to navigate the planning system and to provide a ‘solu-
tionist’ approach to challenges in the system (Parker et al., 2018). While a number of respondents from the public sector
reported that colleagues had recently left the public sector, to join private sector consultancies, no respondents from the
private sector reported colleagues heading to the public sector. A small number of former LPA planners indicated that
they subsequently used their expert knowledge of weaknesses in objectively assessed local housing need to bolster devel-
opers’ cases when applying for controversial housing sites. This ties in with Parker et al.'s findings of an Opening up of the planning process to inputs from a range of private companies who are adept at selling
their ability to offer ‘solutions’ to specific issues as set out within the system. (2018, p. 737) MULDOON-SMITH and McGUINNESS ethical question within the dynamics of local planning practice. This suggests an evolving planning landscape where
many of the positive aspects of local communicative action and stakeholder contribution should be questioned and re-
examined under new circumstances of knowledge status. ethical question within the dynamics of local planning practice. This suggests an evolving planning landscape where
many of the positive aspects of local communicative action and stakeholder contribution should be questioned and re-
examined under new circumstances of knowledge status. In considering these questions, the paper highlights the new contingencies and movements that are re-shaping
notions of knowledge and expertise in the planning discipline (Linovski, 2018; Raco et al., 2016). In contrast to the
recent focus on hybrid relations between public and private planning (Steele, 2009), the paper finds instead sepa-
ration between and knowledge transfer from public to private domains. Instead of hybridity, the paper posits new
assemblages of planning knowledge – as planners reposition themselves in the local planning process and, poten-
tially, uproot collaborative knowledge into new domains. It also sheds new light on how the relative use and position
of expert knowledge affects goal achievement in planning development and local place (Tennoy et al., 2016) and
provokes questions around the original generation of place-based planning knowledge and consequent trust (Parker
et al., 2014). Local government planners are not only moving into private sector consultancy; others are retiring, moving into ac-
ademia, or leaving planning completely. In these cases, valuable tacit knowledge is lost. The authors focus primarily on
the privatisation of public planning knowledge into planning consultancies. However, this almost certainly oversimpli-
fies the situation. A simple binary between public and private does not exist. For example, there are clearly examples of
a hybrid ‘third space’ in planning practice occupied by private outsourcing organisations delivering public services and
fulfilling regulatory responsibilities. In an era of austerity, this is a pragmatic decision, safeguarding expensive planning
knowledge in long-term contractual situations. In addition, not all private sector employers will be representing private
sector interests. For example, private sector consultancies do viability assessments of local plans for both public and
private clients and complete specialist tasks like heritage appraisals for LPAs. Indeed, there is potential for some consul-
tancies to position themselves so they only take on public sector commissions in order to avoid any potential conflicts of
interest. ENDNOTES 1 In an effort to improve perceived delays in the planning system in 2011, the principle in favour of sustainable development was embedded
in NPPF. 1 In an effort to improve perceived delays in the planning system in 2011, the principle in favour of sustainable development was embedded
in NPPF. 2 Planning authorities in England have to demonstrate a 5-year housing supply. If this is out of date, the presumption in favour of sustainable
development applies. 3 The process of moving employees and any liabilities associated with them from the old employer to the new employer by operation of
law. Kevin Muldoon-Smith
https://orcid.org/0000-0002-7416-4062 Kevin Muldoon-Smith
https://orcid.org/0000-0002-7416-4062 Both of these issues offer considerable potential for further research into tacit knowledge and its multi-scalar cre-
ation, transfer, and use in new local assemblages within an evolving planning landscape. Hybrid systems that employ
outsourcing approaches reveal a largely unresearched complexity associated with top-down corporate ownership
and use of this previously held public knowledge and expertise. An interesting line of enquiry would be to consider
how much of the recent shift into private sector planning employment (outlined by the RTPI, 2019) is accounted for
by long-term outsourcing agreements. More optimistically, the social enterprise initiative Public Practice depicts a
counter narrative of public, private, and community interests working together to deliver place strategies from the
bottom up, an approach that protects and potentially enhances the collaborative planning tradition fostered in recent
decades. DATA AVAILABILITY STATEMENT Data sharing not applicable to this paper as no numeric datasets were generated or analysed during the current study. Research is based on respondent testimony and is detailed within the paper. | CONCLUSION In response to the first research question, ‘What is the value of tacit knowledge in contemporary planning practice?’,
the findings in this paper indicate that tacit knowledge is a coveted planning resource. However, it is also one that is
privileged and imbued with significant latent power, depending on the context in which this resource is operationalised. The practical implication for local government planning practice is that there is now an emerging deficit in knowledge
and expertise in local government planning as the public sector faces serious challenges in terms of recruitment and
retention of planning talent (Hills, 2019). In response to the second research question, ‘How is local government tacit
planning knowledge valued, transferred, and reconfigured in new domains of practice?’, relatively stable roles in the
planning process, played by local government planners, are changing due to knowledge movements – for example, from
local government to private consultancy during a sustained period of austerity and local government downsizing. The
tacit knowledge built up through decades of local planning practice – broadly associated with local development plans
– is being re-employed by planning consultancies and then re-appropriated to advise on this same documentation. This
suggests a shifting knowledge/power dynamic that has the potential to influence and potentially redefine some local
planning decisions. Moreover, it is important to note that it is not just the individual planner and their individual knowledge that moves
into another domain; they also take with them the collaborative knowledge built up within a community of practice. This
represents a new knowledge/power dynamic, which has repositioned collaborative knowledge and exposed a challenging MULDOON-SMITH and McGUINNESS | 7 8 | (2019, June 19) Closing remarks RTPI Planning Convention: the future of planning. Innes, J., & Booher, D. E. (2014). A turning point for planning theory? Overcoming dividing discourses. Planning Theory, 14, 195–213. Available
from: https://doi.org/10.1177/1473095213519356 Innes, J., & Booher, D. E. (2014). A turning point for planning theory? Overcoming dividing discourses. Planning Theory, 14, 195–213. Available
from: https://doi.org/10.1177/1473095213519356 Levi-Faur, D. (2009). Regulatory capitalism and the reassertion of the public interest. Policy and Society, 27, 181–191. Available from: https://
doi.org/10.1016/j.polsoc.2008.10.002 Levi-Faur, D. (2009). Regulatory capitalism and the reassertion of the public interest. Policy and Society, 27, 181–191. Available from: https://
doi.org/10.1016/j.polsoc.2008.10.002 Linovski, O. (2016). Politics of expertise: constructing professional design knowledge in the public and private sectors. Journal of Planning
Education and Research, 36, 451–464. Available from: https://doi.org/10.1177/0739456X15620656 Linovski, O. (2016). Politics of expertise: constructing professional design knowledge in the public and private sectors. Journal of Planning
Education and Research, 36, 451–464. Available from: https://doi.org/10.1177/0739456X15620656 Linovski, O. (2018). Shifting agendas: private consultants and public planning policy. Urban Affairs Review, 1, 1–36. Available from: https://
doi.org/10.1177/1078087417752475 Lord, A., & Twedwr-Jones, M. (2018). Getting the planners off our backs: questioning the post-political nature of English planning policy. Planning Practice and Research, 33, 229–243. Available from: https://doi.org/10.1080/02697459.2018.1480194 Lundvall, B. A., & Johnson, B. (1994). The learning economy. Journal of Industrial Studies, 1, 23–42. Available from: https://doi.org/10.1080/
13662719400000002 Massey, D. (2005). For space. London: Sage. Parker, G., Street, E., Raco, M., & Friere-Trigo, S. (2014). In planning we trust?: public interest and private delivery in a co-managed planning
system. Town and Country Planning, 83, 537–540. Parker, G., Street, E., Raco, M., & Friere-Trigo, S. (2014). In planning we trust?: public interest and private del ,
,
,
,
,
,
g ,
(
)
p
g
p
p
system. Town and Country Planning, 83, 537–540. system. Town and Country Planning, 83, 537–540. Parker, G., Street, E., & Wargent, M. (2018). The rise of the private sector in fragmentary planning in England. Planning Theory and Practice,
19, 734–750. Available from: https://doi.org/10.1080/14649357.2018.1532529 Parker, G., Street, E., & Wargent, M. (2018). The rise of the private sector in fragmentary planning in England Parker, G., Street, E., & Wargent, M. (2018). The rise of the private sector in fragmentary planning
19 734–750 Available from: https://doi org/10 1080/14649357 2018 1532529 19, 734–750. Available from: https://doi.org/10.1080/14649357.2018.1532529 Peck, J., & Theodore, N. (2015). Fast policy: experimental statecraft at the thresholds of neoliberalism. REFERENCES Beauregard, R. A. (2005). The textures of property markets: downtown housing and office conversions in New York City. Urban Studies, 42,
2431–2445. Available from: https://doi.org/10.1080/00420980500380345 Booher, D. E., & Innes, J. E. (2002). Network power in collaborative planning. Journal of Planning Education and Research, 21, 221–236. Available from: https://doi.org/10.1177/0739456X0202100301 MULDOON-SMITH and McGUINNESS 8 | Minneapolis, MN: University of Minnesota
Press. Perl, A., & White, D. J. (2002). The Changing Role of Consultants in Canadian Policy Analysis. Policy, Organisation and Society, 21(1), 49–73. Available from: https://doi.org/10.1016/S1449-4035(02)70003-9 Polanyi, M. (1958). Personal knowledge. Chicago, IL: University of Chicago Press. Raco, M. (2014). Delivering flagship projects in an era of regulatory capitalism: state-led privatization and the London Olympics 2012. I t
ti
l J
l f U b
d R
i
l R
h 38 176 197 A
il bl fr
htt
//d i r /10 1111/1468 2427 12025 M. (2014). Delivering flagship projects in an era of regulatory capitalism: state-led privatization and the
nternational Journal of Urban and Regional Research, 38, 176–197. Available from: https://doi.org/10.1111/146 Delivering flagship projects in an era of regulatory capitalism: state-led privatization and the London Ol Raco, M. (2014). Delivering flagship projects in an era of regulatory capitalism: state-led privatization and the London Olympics 2012. International Journal of Urban and Regional Research, 38, 176–197. Available from: https://doi.org/10.1111/1468-2427.12025 l Journal of Urban and Regional Research, 38, 176–197. Available from: https://doi.org/10.1111/1468-2427.1202 M. (2018). Private consultants, planning reform, and the marketisation of local government finance. In J. Fer
f
(
) Raco, M. (2018). Private consultants, planning reform, and the marketisation of local government finance. In J. Ferm, & J. Tomaney (Eds.),
Planning Practice: critical Perspectives from the UK (pp. 132–137). New York, NY: Routledge. lanning Practice: critical Perspectives from the UK (pp. 132–137). New York, NY: Routledge. Raco, M., Street, E., & Freire-Trigo, S. (2016). The new localism, anti-political development machines, and the role of planning consul-
tants: lessons from London’s South Bank. Territory, Politics and Governance, 4, 216–240. Available from: https://doi.org/10.1080/21622
671.2015.1036912 RTPI. (2015). Are cuts putting planning at the brink? RTPI. (2015). Are cuts putting planning at the brink? Sager, T. (1994). Communicative planning theory. London: Ashgate Publishing, Avebury Athenaum Press. Steele, W. (2009). Australian urban planners: hybrid roles and professional dilemmas? Urban Policy and Research, 27, 189–203. Available from:
https://doi.org/10.1080/08111140902908873 Steele, W. (2009). Australian urban planners: hybrid roles and professional dilemmas? Urban Policy and Research, 27, 189–203. Available from:
https://doi.org/10.1080/08111140902908873 Temenos, C., & McCann, E. (2013). Geographies of policy mobilities. Geography Compass, 7(5), 344–357. Available from: https://doi. org/10.1111/gec3.12063 Temenos, C., & McCann, E. (2013). Geographies of policy mobilities. Geography Compass, 7(5), 344–357. Available from: https://doi. org/10.1111/gec3.12063 Tennoy, A., Hansson, L., Lissandrello, E., & Naess, P. (2016). How to cite this article: Muldoon-Smith K, McGuinness D. Tacit domains: The transference of practitioner
know-how in contemporary English planning practice. Area. 2020;00:1–8. Available from: https://doi.
org/10.1111/area.12641 8 | 8 Clifford, B. (2019). Charting outsourcing in UK public planning. Freedom of information request to support Work Package 2: charting outsourc-
ing in UK public planning. Working in the Public Interest Project. Clifford, B. (2019). Charting outsourcing in UK public planning. Freedom of information request to support Work Package 2: charting outsourc-
ing in UK public planning. Working in the Public Interest Project. Dear, M. (1989). Survey 16: privatization and the rhetoric of planning practice. Environment and Planning D
Available from: https://doi.org/10.1068/d070449 Dear, M. (1989). Survey 16: privatization and the rhetoric of planning practice. Environment and Planning D
Available from: https://doi.org/10.1068/d070449 g
Edgar, L. (2019, June 19). RTPI says public sector planning is facing ‘serious’ recruitment challenges. The Planner. g
Edgar, L. (2019, June 19). RTPI says public sector planning is facing ‘serious’ recruitment challenges. The Planner. Fischler, R. (2000). Communicative planning theory: a Foucauldian Assessment. Journal of Planning Education and Research, 19, 358–368. Available from: https://doi.org/10.1177/0739456X0001900405 Fischler, R. (2000). Communicative planning theory: a Foucauldian Assessment. Journal of Planning Education and Research, 19, 358–368. Available from: https://doi.org/10.1177/0739456X0001900405 Hackling, N., & Flynn, A. (2017). Networks, power and knowledge in the planning system: a case stud
Planning, 113, 1–37. Available from: https://doi.org/10.1016/j.progress.2015.12.001 Hackling, N., & Flynn, A. (2017). Networks, power and knowledge in the planning system: a case study of energy from waste. Progress in
Planning, 113, 1–37. Available from: https://doi.org/10.1016/j.progress.2015.12.001 Hackling, N., & Flynn, A. (2017). Networks, power and knowledge in the planning system: a case study of energy from waste. Progress in
Planning, 113, 1–37. Available from: https://doi.org/10.1016/j.progress.2015.12.001 Hackling, N., & Flynn, A. (2017). Networks, power and knowledge in the planning system: a case study of energy from waste. Progress in
Pl
i
113 1 37 A
il bl f
htt
//d i
/10 1016/j
2015 12 001 Healey, P. (1992). Planning through debate: the communicative turn in planning theory. The Town Planning Review, 63, 143–162. Available
from: https://doi.org/10.3828/tpr.63.2.422x602303814821 Healey, P. (1992). Planning through debate: the communicative turn in planning theory. The Town Planning Healey, P. (1992). Planning through debate: the communicative turn in planning theory. The Town Planning Review, 63, 143–162. Available
from: https://doi.org/10.3828/tpr.63.2.422x602303814821 Healey, P. (1992). Planning through debate: the communicative turn in planning theory. The Town Planning
from: https://doi.org/10.3828/tpr.63.2.422x602303814821 from: https://doi.org/10.3828/tpr.63.2.422x602303814821 Hills, V. (2019, June 19) Closing remarks RTPI Planning Convention: the future of planning. Hills, V. 8 | How planners’ use and non-use of expert knowledge affect the goal achievement
potential of plans. Progress in Planning, 109, 1–32. Available from: https://doi.org/10.1016/j.progress.2015.05.002 Tennoy, A., Hansson, L., Lissandrello, E., & Naess, P. (2016). How planners use and non use of expert knowledge affect the goal achievement
potential of plans. Progress in Planning, 109, 1–32. Available from: https://doi.org/10.1016/j.progress.2015.05.002 potential of plans. Progress in Planning, 109, 1–32. Available from: https://doi.org/10.1016/j.progress.2015.05.002 Tewdwr-Jones, M., & Allmendinger, P. (1998). Deconstructing communicative rationality: a critique of habermasian collaborative planning. Environment and Planning A, 30, 1975–1989. Available from: https://doi.org/10.1068/a301975 Tewdwr-Jones, M., & Allmendinger, P. (1998). Deconstructing communicative rationality: a critique of habermasian collaborative planning. Environment and Planning A, 30, 1975–1989. Available from: https://doi.org/10.1068/a301975 Tewdwr Jones, M., & Allmendinger, P. (1998). Deconstructing communicative rationality: a critique of habermasian collaborative planning. Environment and Planning A, 30, 1975–1989. Available from: https://doi.org/10.1068/a301975 Zook, M. A. (2004). The knowledge brokers: venture capitalists, tacit knowledge and regional development. International Journal of Urban and
Regional Research, 28, 621–641. Available from: https://doi.org/10.1111/j.0309-1317.2004.00540.x Zook, M. A. (2004). The knowledge brokers: venture capitalists, tacit knowledge and regional development. International Journal of Urban and
Regional Research, 28, 621–641. Available from: https://doi.org/10.1111/j.0309-1317.2004.00540.x How to cite this article: Muldoon-Smith K, McGuinness D. Tacit domains: The transference of practitioner
know-how in contemporary English planning practice. Area. 2020;00:1–8. Available from: https://doi. org/10.1111/area.12641
|
https://openalex.org/W2031698019
|
https://www.scielo.br/j/acb/a/QJLZqdkyXTSTtjjRsXWYBJc/?lang=en&format=pdf
|
English
| null |
Acta Cirúrgica Brasileira and the Web of Science
|
Acta Cirúrgica Brasileira
| 2,008
|
cc-by
| 598
|
Saul Goldenberg*, Edna Frasson de Souza Montero** *Founder of the Journal
**Assistant Editor *Founder of the Journal
**Assistant Editor **Assistant Editor **Assistant Editor “Acta Cirúrgica Brasileira” is the only Latin-American Journal in the area of experimental surgery. It has been pub-
lished, without interruption, since 1986. It is the Official Journal of the Brazilian Society for the Development of Research in
Surgery [Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia-SOBRADPEC] It is the only continuously published journal in English language solely devoted to experimental/investigative surgery in
Latin America. The Editorial Board considers only papers judged to offer significant contributions to surgical research. ontinuously published journal in English language solely devoted to experimental/investigative surgery in
itorial Board considers only papers judged to offer significant contributions to surgical research. The articles of the Acta Cirúrgica Brasileira, which were cited by journals indexed in the Web of Science, portray 87%
of the subjects concerning to surgery, gastroenterology / hepatology, pharmacology / pharmacy, veterinary science, biology,
transplantation, immunology, medical/research and experimental, and tropical medicine. Geographic representation of research in surgery can be found in the United States (Journal of Surgical Research -
impact factor = 2.038 and total citations = 5.913 and Journal of Investigative Surgery - impact factor = 1.107 and total citations=
417) and in Europe (European Surgical Research - impact factor = 0.684 and total citations = 417). Acta Cirúrgica Brasileira has
joined these journals as representative of Latin America. Research in Surgery is a small field and do not generate as many citations as do larger fields, as clinical surgery. The
impact factor is different comparing both areas. But it is important to emphasize that Acta Cirúrgica Brasileira has been system-
atically cited on WoS indexed journals since the year 1992, reaching a total of 189 citations. Meanwhile, 77% of the total citations
occurred in the period 2003-2008. Brazilian authors were responsible for 69% of the citations, followed by authors from the USA
(11%), Germany (5%), Turkey (5%), England (3%), Japan (2%), Peoples R China (2%), Spain (2%), Austria (1%), Canada (1%),
and Italy (1%). Looking at Scopus databases, we found 98 citations from a total of 337 published articles in the last three years. Full texts are available from URL: http://www.scielo.br/acb, since 1997, in an open free access environment. Impact
factor has been increasing progressively at SciELO databases (reaching an Impact factor=0.1784 (2005), 0.1527 (2006) and
0.1940 (2007)). 1 - EDITORIAL 1 - EDITORIAL Acta Cirúrgica Brasileira - Vol. 23 (3) 2008 - 219 Saul Goldenberg*, Edna Frasson de Souza Montero** Impact factor on a two-year basis
year base 2007
journals in alphabetic order
citations in 2007 to
articles published in
impact
factor
citations
in 2007
to
articles
of 2007
articles
published
in 2007
imediacy
index
titles
all
years 2006 2005 2006+
2005 2006 2005 2006+
2005
1. ACTACIRURGICABRASILEIRA
155 21 24
45 128 104
232
0.1940
2
95
0.0211 Impact factor on a two-year basis
year base 2007 Impact factor on a two-year basis
year base 2007 On behalf of the Directing Board of the Brazilian Society for Development of Research in Surgery and the Editorial
Committee of Acta Cirúrgica Brasileira we are enthusiastic with this improvement and would like to thank our authors for the
citations in WoS indexed journals. On behalf of the Directing Board of the Brazilian Society for Development of Research in Surgery and the Editorial
Committee of Acta Cirúrgica Brasileira we are enthusiastic with this improvement and would like to thank our authors for the
citations in WoS indexed journals. Acta Cirúrgica Brasileira - Vol. 23 (3) 2008 - 219
|
https://openalex.org/W2431079001
|
https://europepmc.org/articles/pmc4923163?pdf=render
|
English
| null |
Systems Biology of Immunomodulation for Post-Stroke Neuroplasticity: Multimodal Implications of Pharmacotherapy and Neurorehabilitation
|
Frontiers in neurology
| 2,016
|
cc-by
| 12,208
|
Original Research
published: 28 June 2016
doi: 10.3389/fneur.2016.00094 S Mohammed Aftab Alam†, V. P. Subramanyam Rallabandi† and Prasun K. Roy* Mohammed Aftab Alam†, V. P. Subramanyam Rallabandi† and Prasun K. Roy* A Edited by:
Anirban Dutta,
Leibniz-Institut für Arbeitsforschung
an der TU Dortmund, Germany Edited by:
Anirban Dutta,
Leibniz-Institut für Arbeitsforschung
an der TU Dortmund, Germany
Reviewed by:
Raju Surampudi Bapi,
University of Hyderabad, India
Mamta Naidu,
GeneSys Research Institute/Center
for Cancer Systems Biology, USA
*Correspondence:
Prasun K. Roy
pkroy@nbrc.ac.in
†Equal first authors. Reviewed by:
Raju Surampudi Bapi,
University of Hyderabad, India
Mamta Naidu,
GeneSys Research Institute/Center
for Cancer Systems Biology, USA Specialty section:
This article was submitted to
Stroke,
a section of the journal
Frontiers in Neurology Received: 22 January 2016
Accepted: 07 June 2016
Published: 28 June 2016 INTRODUCTION remote limb conditioning does indeed activate and upregulate
the pro-survival AKT pathway (19) and long-term protection
against cerebral ischemia is afforded by limb post-conditioning
that is associated with AKT, MAPK, phosphatidylinositol
3-kinase (PI3K), and protein kinase C (PKC) signaling pathways
(20). NF-κB transcription factor family members, such as p50,
p65/RelA in the hippocampus, are regulated by metabotropic
glutamate receptor signaling and c-Rel transcription factor is
responsible for the formation and maintenance of long-term
memory (21). Minocycline directly inhibits matrix metallo-
proteinase (MMP)-9 activation through NF-κB pathway (22). In silico modeling of anti-inflammatory response has been
reported for endotoxins (LPS) and corticosteroids by activating
TLRs in NF-κB (23). Recent investigations have reported that immune responses to
inflammation are non-specific systemic infections associated
with progression of neurodegenerative diseases via activation
of macrophages (1). Minocycline is a tetracycline antibiotic
having several properties, such as anti-inflammatory, anti-
apoptosis, free radical scavenger, and protein misfolding (2). The therapeutic effects of minocycline in preclinical models of
neurodegenerative diseases showed direct neuroprotection and
reduction of microglial inflammatory responses (3). It has been
reported in in vivo studies that minocycline blocks the adhesion
of leukocytes to cerebrovascular endothelial cells induced by
lipopolysaccharides, as well as tumor necrosis factor-α (TNF-α)
production in the brain (4). In vitro studies have reported the
anti-inflammatory effects of minocycline for neuroprotection (5)
and in macrophages (6). Neuroprotective effects of minocycline
include reduction of macrophage activation, prevention of the
potentiation of ischemia-like injury to astrocytes and endothelial
cells consolidating the brain tissue parenchyma (7). Although,
the anti-inflammatory effects of minocycline are known to some
extent, the direct effects of neuroprotection have not been well
investigated in neurodegenerative diseases. Taken together, the modulation of cell survival and death
signaling by hypoxic/ischemic preconditioning appears to be
capable of targeting multiple levels of signaling cascades. Several
inhibitors targeted the point of convergence through distinct and
interacting signaling pathways (crosstalk mechanism) for inflam-
mation by activating macrophages that lead to neuroprotection. Also, cerebral stimulation-based transcranial magnetic stimula-
tion and direct current stimulation enhances brain-derived
neurotrophic factor (BDNF) and tropomyosin-related kinase B
(TrkB) signaling (24, 25). In this study, we harness the convergent
signaling pathways of pharmacotherapy (anti-inflammatory,
immunomodulatory) and neurorehabilitation therapy (func-
tional recovery) for efficient post-stroke neurorestoration by
experimental and systems-level approach. INTRODUCTION We modeled using
the systems biology approach of minocycline modulation of
MMPs through NF-κB signaling pathway, a master regulator of
inflammatory responses along with neurorehabilitation-based
activation in BDNF and TrkB signaling. g
g
Several studies have shown that the physiological neuro-
protection mechanisms that occur after stroke are targeted
through various signaling pathways. Several studies suggest
that the mechanisms associated with either reducing the size of
infarct or enabling neurorestoration, involve the following enti-
ties: (i) anti-high mobility group box-1 activity (8); (ii) NF-κB
(9); (iii) mammalian target of rapamycin (mTOR) inhibitor
(10, 11); (iv) stimulation of toll-like receptors (TLR2 and
TLR4) prior to brain ischemia (12, 13), (v) c-Jun N-terminal
kinase (JNK) inhibitor (14); (vi) p38 mitogen-activated protein
kinase (p38 MAPK) inhibitor (15); (vii) MEK1 pathway (16);
(viii) MAPP/MEK/ERK inhibitor (17); and (ix) Minocycline-
induced reduction of LPS-stimulated p38 MAPK activation,
and stimulation of the phosphoinositide 3-kinase (PI3K)/Akt
pathway (18). Citation:
Alam MA, Subramanyam Rallabandi VP and
Roy PK (2016) Systems Biology of
Immunomodulation for Post-Stroke
Neuroplasticity: Multimodal
Implications of Pharmacotherapy and
Neurorehabilitation. Front. Neurol. 7:94. doi: 10.3389/fneur.2016.00094 June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 1 Alam et al. In Silico Modeling of Multimodal Therapy for Stroke obtained and delayed reperfusion injury can be remedied, if one uses multimodal
intervention of minocycline together with tDCS and rTMS. obtained and delayed reperfusion injury can be remedied, if one uses multimodal
intervention of minocycline together with tDCS and rTMS. conclusion: Additive beneficial effect is, thus, noticed for pharmacotherapy along with
neurorehabilitation therapy, by maneuvering the dynamics of immunomodulation using
anti-inflammatory drug and cerebral stimulation for augmenting the functional recovery
after stroke, which may engender clinical applicability for enhancing plasticity, rehabilita-
tion, and neurorestoration. Keywords: stroke, neuroprotection, rehabilitation, minocycline, direct current stimulation, transcranial magnetic
stimulation Frontiers in Neurology | www.frontiersin.org MATERIALS AND METHODS There are numerous cellular responses, stress events, neuronal
death, and inflammatory mechanisms, including over-activation
of microglia as shown in Figure 1. We utilized and targeted
anti-inflammatory drug in our approach. We formulated
various cell kinetics interactions utilizing the systems biology
platform for pharmacotherapy (Module 1) and neurorehabilita-
tion (Module 2)-based activation through different signaling
pathways, such as NF-κB, BDNF, and TrkB. To formulate and Currently, little is known about endogenous counter regula-
tory immune mechanisms that can induce neurorestoration. The
glycogen synthase kinase-3β (AKT/GSK-3β) pathway has been
recognized as a protective pathway against cerebral ischemic
injury. In cerebral ischemia models, it has been shown that June 2016 | Volume 7 | Article 94 2 Alam et al. In Silico Modeling of Multimodal Therapy for Stroke FIGURE 1 | Cascade of cell signaling events post-stroke and enabling neuroprotection using minocycline. FIGURE 1 | Cascade of cell signaling events post-stroke and enabling neuroprotection using minocycline. shown in Module 1. The sequence depicts a chronological order
of the formation of different biochemical species (mentioned on
the right side after % symbol) with their corresponding reaction
kinetic equation (on the left side).h model the effect of therapeutic interventions, we activated
the corresponding signal transduction factor accordingly. For
minocycline, activation input was in the form of a constant
single impulse or step function, while for the transcranial
direct current stimulation (tDCS) and repetitive transcranial
magnetic stimulation (rTMS) inputs, we used repeated series
of electrical or magnetic pulses involved in cerebral stimula-
tion. The chemical reactions of the modules were constructed
using the framework of ordinary differential equations (ODEs),
which were then solved by numerical computation using the
Runge–Kutta method. t
The non-zero initial concentration of the chemical species and
the association and dissociation rate constants are taken from
previous experiments (23, 26) given in APPENDIX (Table A1). The ODE equations shown in Module 1 were solved using ODE23
solver in MatlabR2013a. Pharmacotherapy (Minocycline) through
NF-κB Signaling Pathway To elucidate the process of neurorehabilitation therapy using
tDCS and rTMS via BDNF and TrkB pathway. We constructed
the upstream and downstream dynamics of the pathway using
currently available data (28). The corresponding chemical reac-
tions are formulated as ODE and shown in Module 2. g
g
y
We formulated and elucidated the cascade of cell signaling
events using ODEs that were solved using ODE23 solver in
MatlabR2013a. We modeled the inflammatory mechanism of
minocycline through regulation of genes and proteins that
significantly corresponded to NF-κB transcriptome as shown
in Figure 2. Studies have suggested that minocycline-induced
suppression of NF-κB activity is mediated by the inhibition
of M1 microglia and activation of M2 microglia. All the
sequential chemical processes are explained in Module 1. The
in vitro and in vivo studies have shown that both the acute
and chronic doses of minocycline lead to suppression of p65
phosphorylation and nuclear translocation accompanied by
downregulation of NF-κB activity and endogenous MMP9
protein levels (22). Frontiers in Neurology | www.frontiersin.org Pharmacotherapy (Minocycline)h py (
y
)
The results of the signaling activation by the pharmacological agent
minocycline are shown in Figure 4. A sub-optimal dose of 4.5 mg
kg−1 was chosen from a dose escalation study of minocycline in
stroke patients (81). Our findings delineate the inflammatory
mechanism of minocycline through regulation of genes and pro-
teins that correspond to the NF-κB transcriptome. Our simulation
has shown the molecular mechanism of minocycline that could
be attributed to modulation of NF-κB signaling. Minocycline
suppressed NF-κB activation in neurons and glial cells and was
correlated with attenuation of IκBα kinase (IKK) activation, IκBα
phosphorylation and degradation, and p65 phosphorylation and
nuclear translocation. The inhibition of IKK was found to be
associated with suppression of activated-microglia (neurotoxic
M1 microglia) and correspondingly enhanced the restorative
microglia (neuroprotective M2 microglia). Furthermore, the
simulation demonstrated that minocycline upregulated TNF-α
expression. Enforced TNF-α expression induced NF-κB activity
and minocycline rescued through inhibition of iNOS and NO
production in cells. Our simulated results are consistent with
the experimental findings that suppressed NF-κB activation and
abrogated the inhibitory effect of minocycline on the transcrip-
tion factor, TNF-α. These results suggest that minocycline led to
suppression of p65 phosphorylation and nuclear translocation
accompanied by downregulation of NF-κB activity and endog-
enous MMP9 protein levels and its target, PTGS2 gene. Another possible signaling mechanism is phospholipase
C gamma (PLC-γ) that in turn cleaves PIP2, diacylglycerol
(DAG), and inositol trisphosphate (IP3). DAG remains bound
to membrane, whereas IP3 is released as a soluble structure
into the cytosol. Then IP3 diffuses through cytosol and binds
to IP3 receptors, particularly calcium channels in a smooth
endoplasmic reticulum, and then activates Ca2+ in calmodulin
kinase (CaMK) activity. Correspondingly, DAG activates PKC
for plasticity (34). CaMKIII is activated by Ca2+ and inactivated
by S6K. CaMKIII inhibits eukaryotic elongation factor 2 (eEF2),
the net effect of Ca2+ on elongation factor is inhibitory and of S6K
is excitatory. eEF2 is the major substrate for CaMKIII. CaMKIII
catalyzes eEF2 phosphorylation at thr-56 and thr-58, strictly in
the presence of Ca2+ and CaM (35). CaMKIII phosphorylates
eEF2 to render it inactive. Dephosphorylation of eEF2 by PP2A
restores its activity.h In the simulation, a minocycline dose of 4.5 mg kg−1 induced
TNF-α activity for 6 h as shown in Figure 4A. Cerebral Stimulation (rTMS and tDCS) through
BDNF and TrKB Brain-derived neurotrophic factor activates TrkB through several
downstream signaling pathways, such as AKT, CaMK, Ras/Raf/
MEK/ERK leading to cell survival, growth, and neuroplasticity
as shown in Figure 3. BDNF activates TrkB stimulation via
phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) and
also activates proteins like Shc, Grb-2, and Gab-1. The PI3K
is also activated by binding to Ras homolog enriched by brain
glutamine triphosphate (Ras-GTP). TMS was delivered to male
Sprague Dawley rats using 1600 stimuli at 5 Hz in four blocks of
each 400 stimuli in 2.5 min with 1 min inter-block interval (24). Using the dynamics of known NF-κB stages (26, 27), the action
of minocycline via the signaling pathway was represented as June 2016 | Volume 7 | Article 94 3 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. Anodal tDCS was applied with current density of 0.04 mA/cm2,
total charge of 0.048 C/cm2 for 20 min (25). Activated PI3K phos-
phorylates PtdIns[3,4]P2 (PIP2) and PtdIns[3,4,5] P3 (PIP3),
and then PIP3 is dephosphorylated by phosphotase and tensin
homolog (PTEN). PIP3 activates AKT (also known as protein
kinase B) leading to the formation of Rheb-GTP, a regulator of
rapamycin (TOR) (29, 30). AKT needs phosphorylation twice to
become active. PIP3 binds to AKT and recruits it in the mem-
brane and does the same for Pyruvate dehydrogenase lipoamide
kinase isozyme 1 (PDK1). Anodal tDCS was applied with current density of 0.04 mA/cm2,
total charge of 0.048 C/cm2 for 20 min (25). Activated PI3K phos-
phorylates PtdIns[3,4]P2 (PIP2) and PtdIns[3,4,5] P3 (PIP3),
and then PIP3 is dephosphorylated by phosphotase and tensin
homolog (PTEN). PIP3 activates AKT (also known as protein
kinase B) leading to the formation of Rheb-GTP, a regulator of
rapamycin (TOR) (29, 30). AKT needs phosphorylation twice to
become active. PIP3 binds to AKT and recruits it in the mem-
brane and does the same for Pyruvate dehydrogenase lipoamide
kinase isozyme 1 (PDK1). is through downstream signaling of Ras/Raf/MEK/ERK pathway
for cell survival, growth, and neuroplasticity.h The non-zero initial concentration of chemical species is given
in APPENDIX (Table A2). All these parameters are taken from
the experimental studies related to memory, learning, and synap-
tic plasticity through BDNF and TrkB signaling. The implications
of tDCS and rTMS in the present study are to enhance the post-
stroke motor-learning along with functional recovery in ischemic
stroke patients. RESULTS We simulated the biochemical processes of both Modules 1 and 2. Our observations and inferences are explained in details below. Cerebral Stimulation (rTMS and tDCS) through
BDNF and TrKB The association and dissociation rate constants
are taken from experimental studies as given in APPENDIX
(Table A3). The aforesaid equations are given in Module 2, which
were solved by ODE23 solver in MatlabR2013a. y
In the membrane, PDK1–PIP3 complex phosphorylates AKT
on Thr308 and further phosphorylates on Ser-473 by PIP3-PDK2. Both these phosphorylates are reversed by protein phosphatase
2A (PP2A). The doubly phosphorylated AKT becomes active and
phosphorylates tuberous sclerosis 1,2 (TSC1–TSC2), which in
turn regulates Rheb-GTP levels. The unphosphorylated complex
has GTPase-activating protein (GAP)-type properties toward
Rheb, while TSC1–TSC2 hydrolyzes Rheb-GTP to Rheb-GDP
(31). The active AKT inactivates TSC1–TSC2 and only Rheb-
GTP remains. Therefore, the net effect is, PIP3 activates AKT
leading to activation of downstream target TOR. Furthermore,
Rheb-GTP activates TOR and the converged input from MAPK
leads to S6K activation, forming active 40S for translation (32, 33). The Rheb-GTP binds to the TOR_complex to stimulate kinase
activity through phosphorylation in each kinase, viz. MAPK,
TOR_complex, and PDK1. Next, dephosphorylation occurs at all
the sites by PP2A. The double- and triple-phosphorylated S6K
becomes active and phosphorylates S6, which is a subunit of 40S
ribosomal protein. June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org Pharmacotherapy (Minocycline)h The neutral IKK
activity gradually reduced from 60 to 90 min and then asymp-
totically saturated downwards to baseline as shown in Figure 4B. Similarly, the inactive form of IKK increased from 60 to 90 min
and then saturated to baseline as shown in Figure 4C. The active
IKK expression increased from 60 to 90 min, peaked at 90 min and
then fell gradually till 120 min and saturated downwards to basal
level as shown in Figure 4D. Free cytoplasmic IκBα increased
from 60 to 90 min, peaked at 120 min and then gradually fell till
180 min and oscillated as shown in Figure 4E. The cytoplasmic
IκBα|NF-κB activity initially fell till 60 min, then peaked at
120 min, fell down till 180 min, and then showed oscillatory The S6K phosphorylates CaMKIII at Ser-366 and decreases its
activity and thereby increases the level of eEF2 (36). Calmodulin
dependence of CaMKIII activity was measured in terms of eEF2
phosphorylation (37). Next, the active S6K is added to CaMKIII
and time course of CaMKIII is measured. Then, active eEF2-
thr-36 is measured with respect to time. The dose–response for
40S complex is measured for different 40S concentrations (38),
the dephosphorylation reaction and the formation of phospho-
rylated eEF2 (28). The 40S and eEF2 bind to form the translation
complex, leading to protein synthesis. MAPK is downstream of
PI3K as well as CaM-Ca4. The MAPK activity is closely related to
synaptic activity leading to Ca2+ influx. The alternate mechanism June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 4 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. FIGURE 2 | Minocycline-activated anti-inflammatory response through NF-κB signaling pathway. FIGURE 2 | Minocycline-activated anti-inflammatory response through NF-κB signaling pathway. The expression of IKKa|IκBα complex increased from 60 to
90 min, gradually fell till 180 min, and then oscillated as in
Figure 4J. The expression of IKKa|IκBα|NF-κB complex peaked
at 60 min and then fell afterwards as shown in Figure 4K. The
nuclear IκBα|NF-κB expression increased from 60 to 120 min
and then gradually fell till 180 min and oscillated as in Figure 4L. Free and phosphorylated IκBα bounded to cytoplasmic NF-κB behavior as shown in Figure 4F. The free nuclear IκBα increased
from 60 to 140 min, fell down till 180 min and finally damped
as in Figure 4G. DISCUSSION Oxidative stress and inflammation are the two major patho-
physiological mechanisms involved during early and late phases
of ischemic stroke. Brain tissue is not armed with antioxidant
defenses, so reactive oxygen species and other free radicals/oxi-
dants released by inflammatory cells, threaten tissue viability in
the core ischemic region. This study targets the molecular aspects
of inflammation in ischemic stroke and offers potential therapeu-
tic strategies that target neuroinflammation and modulates the
innate immune system. In addition to antibiotic activity, mino-
cycline exhibits anti-inflammatory responses in both monocytes
and macrophages. Earlier studies have reported that minocycline
causes significant reduction in the inflammatory response of
LPS-challenged monocytes, reducing LPS-induced transcription
of pro-inflammatory TNF-α, interleukin-1 beta (IL-1β) (82),
interleukin-6 (IL-6), and cyclooxygenase-2 (COX-2) (83), the
LPS stimulated TNF-α, IL-6, and PGE2 release. Minocycline
inhibited LPS-induced activation of the lectin-like oxidized low-
density lipoprotein receptor-1 (LOX-1), NF-κB, LPS-induced
TNF-α factor (LITAF) and the Nur77 nuclear receptor (20). It has
been reported that the neuroprotective effects of minocycline are
associated with inhibition of iNOS induction and NO production
in glial cells, which are mediated by the LPS-induced production
of TNF-α (84). Continuing the formulation further, we note that the kinase
CaMKIII activity increased till 240 s and then saturated upwards
as shown in Figure 5H. We found active AKT increase till 100 s,
decreased after 480 s and then downward saturation to baseline
as in Figure 5I. We inferred that the BDNF synthesis rate was
maximum for the concentration of 3.7 nM as shown in Figure 5J. Moreover, we noticed eEF2 synthesis rate linearly increased when
plotted against eEF2 concentration, for both basal kinase activity
and for BDNF concentration of 3.7 nM (Figure 5K). We found
that the synthesis rate of eEF2 for BDNF concentration of 3.7 nM
was double the basal kinase level, when the eEF2 concentration
is 5 nM as shown in Figure 5K. We also showed that the 40S syn-
thesis rate peaked at 500 nM of 40S concentration for both basal
kinase level and for BDNF level of 3.7 nM, and 40S synthesis rate
was higher for BDNF level of 3.7 nM than that for basal kinase
level, as shown in Figure 5L. We also found that protein synthesis rate is constant for
all BDNF concentrations for Ca2+ = 0.5 nM and notice that
increase of synthesis rate occurs beyond 0.1 nM concentration
for Ca2+ = 0.08 nM. Pharmacotherapy (Minocycline)h The free nuclear NF-κB activity increased from
60 to 90 min, fell down from 90 to 120 min, and then showed
oscillatory behavior as in Figure 4H.h The PTGS2 gene transcription increased from 60 to 120 min,
fell down till 180 min, and then oscillated as shown in Figure 4I. June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 5 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. peaked at 60 min, fell gradually till 90 min and damped as in
Figure 4M. Free cytoplasmic IκBα expression increased from 60
to 120 min then gradually fell till 180 min, and finally oscillated
as in Figure 4N. The total cytoplasmic IκBα activity initially
fell down till 60 min and then onward gradually increased
till 120 min, and finally showed oscillatory behavior as in
Figure 4O. It is important to note that the temporal profile for
the chemical species will not change for different concentrations
of minocycline. of 3.7 nM, till Ca2+ = 0.1 μM. Thereafter, the protein synthesis
activity was constant for higher Ca2+ concentrations. However,
the synthesis rate was initially higher for BDNF level of 3.7 nM
than for basal kinase activity, for lower values of Ca2+ concentra-
tion (<0.1 μM), as in Figure 6C. As mentioned earlier, we activated the corresponding signal
transduction factor accordingly (inositol triphosphate IP3, and
the related compound, phosphatidyl-IP3, viz. PIP3). First, the
initial activation of IP3 through phospholipase C (PLC-γ) and the
activation of PIP3 through PI3K were plotted for TMS and DCS. TMS showed higher level of IP3 than PIP3 with higher number
of reactant molecules generated till 150 s, and then the number
of molecules saturated to a definitive level as in Figure 6D. DCS
showed higher PIP3 than IP3 with an increased number of mol-
ecules till 150 s as in Figure 6E. Neurorehabilitation Therapy Using tDCS
and rTMSh The simulations showed increased activity of TrkB*2 from 0 to
500 s, and then fell till 1000 s, and then asymptotically saturated
downwards to a definitive level as shown in Figure 5A. The Shc*
activity increased linearly when plotted against BDNF till the
BDNF concentration reached 2 nM as shown in Figure 5B. The
PLC-γ activity increased linearly when plotted against BDNF till
the concentration of 3.7 nM as in Figure 5C. Furthermore, the
PIP3 activity linearly increased as shown in Figure 5D, while
the cell elongation factor (eEF2) eEF2thr-56 showed sigmoid
relationship when plotted against low concentrations of the
calcium-binding protein Calmodulin, CaM (measured in terms
of negative log) as in Figure 5E. eEF2 activity was observed to
linearly increase with time as in Figure 5F. We observed that
40S complex activity displayed a declining sigmoidal function
with an increased activity till 300 nM when plotted against 40S
concentration, followed by constant activity (very slowly declin-
ing) from 300 to 600 nM, and thereafter finally the activity rises
beyond 600 nM as in Figure 5G. Thus, we have shown that both TMS and DCS activated
CaMKIII that shows the cell survival and synaptic plasticity. To draw a perspective, we elucidated that all the modalities
(minocycline, tDCS, rTMS) have different pathways with com-
mon activation of N-methyl-d-aspartate (NMDA) receptors. Therefore, pharmacotherapy and neurorehabilitation can be
incisively combined for additive beneficial effect. DISCUSSION This suggests that BDNF = 3.7 nM and
lower Ca2+ concentration leads to higher protein synthesis rate
as shown in Figure 6A. We plotted the percentage of kinase
enzymes CaMKIII and MAPK activity against Ca2+ concentra-
tion and found MAPK activity peaked for Ca2+ = 0.5 nM, while
CaMK activity peaked for Ca2+ = 1.0 nM as shown in Figure 6B. The protein synthesis rate for constant CamKIII = 0.6 μM gradu-
ally decreased for both basal kinase activity and for BDNF level Frontiers in Neurology | www.frontiersin.org Pharmacotherapy: Minocyclinehl py
y
The regulation of inflammatory genes and proteins in NF-κB
signaling pathway are MMPs and Cox-2. MMPs are a family
of zinc-dependent proteases responsible for the degradation of
extracellular matrix proteins and capable of causing bioactive
molecules. Cox-2 inhibitors are non-steroidal anti-inflammatory
drugs (NSAIDs). The in vitro models showed direct neuroprotec-
tion by minocycline as well as inhibition of other inflammatory June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 6 Alam et al. In Silico Modeling of Multimodal Therapy for Stroke FIGURE 3 | BDNF and TrkB signaling pathway. FIGURE 3 | BDNF and TrkB signaling pathway. mediators, such as iNOS, MMPs, TNF-α, and tissue plasminogen
activator (tPA). However, some earlier studies have reported
expression of inflammatory cytokines, such as TNF-α in ischemic
neurons (85) and tPA (86), and generation of neuronal tPA has
been thought to mediate microglial activation. Thus, these studies
suggested that neurons may be capable of secreting inflamma-
tory mediators themselves from classical immune cells, includ-
ing microglia and other glial cells, such as astrocytes. Also the
neuronal survival depends on the endogenous or exogenous tPA,
which can be either neuroprotective or neurotoxic. Similar conclu-
sions could be made of neuronal generation of iNOS and MMPs. MMPs 2 and 9 levels are elevated a few hours after ischemia (87)
and maintain increased activity for days after the onset of stroke
(88). The specific class of agents inhibits these enzymes, reverts
the breakdown of laminin (89), and prevents increased barrier
permeability, edema, and hemorrhage after ischemic stroke (90). Ischemic stroke activates a complex cascade of events and multiple mechanisms. The models of brain injury, which involve
matrix degradation and vascular instability, targets inhibition of
proteolytic cascade. However, there are limitations for the usage
of MMP inhibitors as therapeutic agents because of their poor
solubility. Minocycline has been shown to be a neuroprotective
agent by inhibiting MMP2 and MMP9 activation by ischemia
(91). The dysregulation of the proteolytic cascade at the level
of the endothelial and microglial cells is one of the common
pathological mechanisms of ischemic brain damage. Minocycline
targets through the interference of this cascade and might be the
key pathway for neuroprotection and salvage of injured tissue. Animal models of permanent cerebral ischemia showed that
minocycline treatment was protective and beneficial in cerebral
ischemia by mechanisms that are not linked to the production
of free radicals during reperfusion. Frontiers in Neurology | www.frontiersin.org Transcranial Magnetic Stimulationf Transcranial Magnetic Stimulation
Earlier study have reported the effects of rTMS and illustrated
the mechanisms of rTMS in regulating cognitive capacity. rTMS
enhances spatial memory behavior, neuron and synapse mor-
phology in the hippocampus, and synaptic protein markers and
BDNF/TrkB in normal aging mice (103). Aging mice inhibited
the activation of BDNF–TrkB signaling pathway and showed
hippocampal-dependent cognitive impairment in relative to
adult animals, with the reduced transcription and expression of
synaptic protein markers, such as growth-associated protein 43
(GAP43), synaptophysin (SYN), post-synaptic density protein 95
(PSD95), including decreased synapse density, and PSD thick-
ness. Surprisingly, low-intensity rTMS (110% average resting
motor threshold intensity, 1 Hz) triggered the activation of BDNF
and TrkB, upregulated the level of synaptic protein markers,
increased synapse density and PSD thickness, and reversed the
spatial cognition dysfunction in aging mice. On the other hand,
high-intensity rTMS (150% average resting motor threshold
intensity, 1 Hz) was harmful, inducing reduction of PSDs thick-
ness, disordered synaptic structure, as well as reduction in the
number of synapses, and downregulation of BDNF–TrkB and
synaptic proteins. The aging-induced cognitive deficits depends
on the intensity level of TMS, which are closely associated with
hippocampal structural synaptic plasticity that plays an impor-
tant role in regulating cognitive behavior via changing structural
synaptic plasticity through BDNF signaling. The effect of rTMS
on functional recovery and its underlying molecular mechanism
has been studied by assessing proteins associated with neural
plasticity in a sub-acute ischemic rat model (104). A total of 3,500
impulses with 10 Hz frequency were applied to the ipsilesional
cortex from post-operative day 4 over a 2-week period. The study
reported that rTMS group showed more functional improve-
ment on the beam balance test and the immunohistochemistry
analysis showed stronger Bcl-2 and weaker Bax expression when
compared with the sham group and noticed no significant differ-
ence in the expressions of NMDA and MAP-2 (104). However,
rTMS may increase or decrease motor cortical excitability mostly
depending on the characteristics of the stimulation protocol
(105). Non-invasive cortical stimulation upregulates excitability
in M1 lesioned hemisphere and downregulates in M1 intact
hemisphere that could contribute to correcting abnormalities in
inter-hemispheric inhibition identified after stroke (106). Thus,
both the pharmacotherapy and neurorehabilitation therapy
converge through the NMDA receptor activation. Frontiers in Neurology | www.frontiersin.org Pharmacotherapy: Minocyclinehl Understanding inflamma-
tory interactions of all brain cell types is needed to identify how
they may be manipulated to provide neuroprotection. Studies of
minocycline effects on brain cells in addition to microglia are t
Ischemic stroke activates a complex cascade of events and
tetracycline antibiotics may exert anti-inflammatory effects by June 2016 | Volume 7 | Article 94 7 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. (102). Furthermore, neurophysiological and in silico modeling
studies are required to understand the neuromodulating effects
of tDCS, and help in determining the optimal levels of anodal and
cathodal stimulation that is beneficial for stroke patients. timely, as minocycline has shown efficacy in clinical studies for
various neurodegenerative disorders (92, 93) and ischemic stroke
(81, 94, 95). Thus, further investigations are needed for a better
understanding of the complexities of immune responses of vari-
ous types of cell bodies following brain injury. Direct Current Stimulationh The primary mechanism of tDCS for inducing cortical excit-
ability shifts is a sub-threshold modulation of the neuronal
resting membrane potential. The anodal stimulation outcome
is a sub-threshold depolarization, while cathodal stimulation
hyperpolarizes neuronal membranes. During a short tDCS,
which elicits no after-effects (stimulation duration of about 4 s),
synaptic mechanisms are not involved, as shown by the absence
of effect of NMDA receptor antagonists, the GABA agonist
lorazepam and the monoamine reuptake blocker amphetamine
on the tDCS-induced excitability changes under these condi-
tions. Furthermore, the after-effects are not due to reverberating
electrical circuits or other purely electrical phenomena, as shown
in early animal experiments. They depend on modifications of
NMDA receptor efficacy, since these are blocked by the NMDA
receptor antagonist dextromethorphan, but prolonged by the
partial NMDA receptor agonist d-cycloserine (96). The tDCS
polarity-dependent shift of NMDA receptor function seems
to be initiated by the respective membrane potential shift and
probably by the accompanying cortical activity modification,
because it is prevented by the sodium channel blocker (carba-
mazepine). Likewise, tDCS requires the neurophysiological
experimental studies for the selection of electrode montage in
stroke (97). Furthermore, in silico modeling studies are required
to understand the neuromodulatory effects of tDCS and helps in
determining the optimal levels of anodal and cathodal stimula-
tion that is beneficial for stroke patients. i
Earlier studies also reported a decrease in IP 3 receptor mRNA
level in the cortex at 4 h after a 45 min ischemic insult; however,
lesser change was noticed for IP3 3-kinase mRNA levels during
the initial 8 h after reperfusion (98). Also, IP3 receptor mRNA
level in the peri-infarct areas was also reduced, specifically at a
delayed time of reperfusion. The staining of cortical neurons in
the infarct area showed morphological changes between 4 and 8 h
after reperfusion (99). Thus, the decrease in IP3 receptor mRNA
level probably occurred at a time prior to alteration of neuron
morphology. A recent study showed that DCS stimulation-
induced vasodilation occurs without IP3 receptor activation (100). Brain-derived neurotrophic factor induces the transformation
of early- to late-phase long-term potentiation (LTP) in the pres-
ence of protein synthesis inhibitors and BDNF–TrkB signaling is
involved in synaptic tagging (101). BDNF activates the RAS/RAF
signaling pathway and produces ERK, promoting gene transcrip-
tion through cAMP-response element binding protein (CREB)
in the cell nucleus. Direct Current Stimulationh NMDA activation on the cell membrane
produces a calcium influx that activates calcium CaMK IV, phos-
phorylating glycogen synthase kinase 3B (GSK3B) and allowing
B-catenin to activate CREB. Recent studies have provided differ-
ent mechanistic explanation for the early and late phases of LTP. The mechanism for later phases of LTP required for memory stor-
age is the complex of CaMK signaling with the NMDA receptor Earlier studies also reported a decrease in IP 3 receptor mRNA
level in the cortex at 4 h after a 45 min ischemic insult; however,
lesser change was noticed for IP3 3-kinase mRNA levels during
the initial 8 h after reperfusion (98). Also, IP3 receptor mRNA
level in the peri-infarct areas was also reduced, specifically at a
delayed time of reperfusion. The staining of cortical neurons in
the infarct area showed morphological changes between 4 and 8 h
after reperfusion (99). Thus, the decrease in IP3 receptor mRNA
level probably occurred at a time prior to alteration of neuron
morphology. A recent study showed that DCS stimulation-
induced vasodilation occurs without IP3 receptor activation (100). Brain-derived neurotrophic factor induces the transformation
of early- to late-phase long-term potentiation (LTP) in the pres-
ence of protein synthesis inhibitors and BDNF–TrkB signaling is
involved in synaptic tagging (101). BDNF activates the RAS/RAF
signaling pathway and produces ERK, promoting gene transcrip-
tion through cAMP-response element binding protein (CREB)
in the cell nucleus. NMDA activation on the cell membrane
produces a calcium influx that activates calcium CaMK IV, phos-
phorylating glycogen synthase kinase 3B (GSK3B) and allowing
B-catenin to activate CREB. Recent studies have provided differ-
ent mechanistic explanation for the early and late phases of LTP. The mechanism for later phases of LTP required for memory stor-
age is the complex of CaMK signaling with the NMDA receptor One of the challenges for antibiotic therapy is the need to
identify the optimum dose level. Recently, a reliable and feasible
approach of dose estimation using chemical binding kinetics was
proposed by Abel et al. (107). Another challenge is determining
the impact of combinational multiple drug therapies on several
proteins. A recent study suggested an approach using linear super-
position of their responses to individual therapy (108). Utilizing
these approaches, we can develop in silico models that could provide June 2016 | Volume 7 | Article 94 8 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. Direct Current Stimulationh In Silico Modeling of Multimodal Therapy for Stroke
FIGURE 4 | Minocycline-induced TNF-α activity in NF-κB pathway. FIGURE 5 | Cerebral stimulation induced BDNF and TrkB signaling. Alam et al. FIGURE 4 | Minocycline-induced TNF-α activity in NF-κB pathway. FIGURE 4 | Minocycline-induced TNF-α activity in NF-κB pathway. FIGURE 5 | Cerebral stimulation induced BDNF and TrkB signaling. FIGURE 5 | Cerebral stimulation induced BDNF and TrkB signaling. FIGURE 5 | Cerebral stimulation induced BDNF and TrkB signaling. June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 9 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. FIGURE 6 | Cerebral stimulation induced IP3, PIP3, and CaMKIII activity. FIGURE 6 | Cerebral stimulation induced IP3, PIP3, and CaMKIII activity. CONCLUSION In this paper, we utilize a systems biology approach to maneuver
the dynamics of immunomodulation using linear combination
of doses of pharmacotherapy (minocycline) in NF-κB signaling
pathway along with adjuvant neurorehabilitation therapy (rTMS
or tDCS) through BDNF and TrkB signaling pathway stimula-
tion for enhancing synaptic plasticity, rehabilitation, and neu-
rorestoration. Thus, a thorough understanding and modeling of
pathways, along with the optimal therapeutic doses could lead us
to prevent cell death at an earlier stage and with a higher chance
of maintaining the long-term viability of the cell protection
after stroke. To conclude, further studies are required to dissect,
report, and analyze these pathways toward the goal of improving
neurorestoration by multimodal therapy for stroke and related
neurovascular disorders. ACKNOWLEDGMENTS We would like to thank Rajiv Ramaswamy (National Brain Research
Centre, India) for proof reading and necessary language editing. AUTHOR CONTRIBUTIONS insight into the design of clinical trials of immunomodulatory
therapies, ranging from optimal patient-specific dose selection,
and duration of proposed therapeutic interventions (109). The research was conceived and planned by PR, jointly with
inputs from MA and VR. The numerical experimentation was
performed by VR and the biological studies investigated by MA. All authors examined and evaluated the data. VR, MA, and PR
wrote the manuscript. All authors read and approved the final
manuscript and have no conflict of interests. REFERENCES Mathematical
model of NF-kappaB regulatory module. J Theor Biol (2004) 228:195–215. doi:10.1016/j.jtbi.2004.01.001 8. Qiu J, Nishimura M, Wang Y, Sims JR, Qiu S, Savitz SI, et al. Early release of
HMGB-1 from neurons after the onset of brain ischemia. J Cereb Blood Flow
Metab (2008) 28:927–38. doi:10.1038/sj.jcbfm.9600582 9. Baker RG, Hayden MS, Ghosh S. NF-κB, inflammation, and metabolic
disease. Cell Metab (2011) 13:11–22. doi:10.1016/j.cmet.2010.12.008 27. Ulgen BO, Field MG, Qureshi W, Knight RA, Stephanou A, Latchman DS,
et al. The role of minocycline in ischemia-reperfusion injury: a comprehen-
sive review of an old drug with new implications. Recent Pat Cardiovasc Drug
Discov (2011) 6:123–32. doi:10.2174/157489011795933783 10. Chauhan A, Sharma U, Jagannathan NR, Reeta KH, Gupta YK. Rapamycin
protects against middle cerebral artery occlusion induced focal cerebral isch-
emia in rats. Behav Brain Res (2011) 225:603–9. doi:10.1016/j.bbr.2011.08.035 28. Jain P, Bhalla US. Signaling logic of activity-triggered dendritic protein
synthesis: an mTOR gate but not a feedback switch. PLoS Comput Biol (2009)
5:e1000287. doi:10.1371/journal.pcbi.1000287 11. Carloni S, Girelli S, Scopa C, Buonocore G, Longini M, Balduini W. Activation of autophagy and Akt/CREB signaling play an equivalent role
in the neuroprotective effect of rapamycin in neonatal hypoxia-ischemia. Autophagy (2010) 6:366–77. doi:10.4161/auto.6.3.11261 29. Yuen EC, Mobley WC. Early BDNF, NT-3, and NT-4 signaling events. Exp
Neurol (1999) 159:297–308. doi:10.1006/exnr.1999.7148 f 12. Caso JR, Pradillo JM, Hurtado O, Lorenzo P, Moro MA, Lizasoain I. Toll-like receptor 4 is involved in brain damage and inflammation after
experimental stroke. Circulation (2007) 115:1599–608. doi:10.1161/
CIRCULATIONAHA.106.603431 f 30. Alessi DR, James SR, Downes CP, Holmes AB, Gaffney PR, Reese CB,
et al. Characterization of a 3-phosphoinositide-dependent protein kinase
which phosphorylates and activates protein kinase Balpha. Curr Biol (1997)
7:261–9. doi:10.1016/S0960-9822(06)00122-9 13. Ziegler G, Harhausen D, Schepers C, Hoffmann O, Röhr C, Prinz V, et al. TLR2
has a detrimental role in mouse transient focal cerebral ischemia. Biochem
Biophys Res Commun (2007) 359:574–9. doi:10.1016/j.bbrc.2007.05.157 31. Inoki K, Li Y, Xu T, Guan KL. Rheb GTPase is a direct target of TSC2 GAP
activity and regulates mTOR signaling. Genes Dev (2003) 17:1829–34. doi:10.1101/gad.1110003 14. Wang LW, Tu YF, Huang CC, Ho CJ. JNK signaling is the shared pathway
linking neuroinflammation, blood-brain barrier disruption, and oligo-
dendroglial apoptosis in the white matter injury of the immature brain. J Neuroinflammation (2012) 9:175. doi:10.1186/1742-2094-9-175 32. Isotani S, Hara K, Tokunaga C, Inoue H, Avruch J, Yonezawa K. REFERENCES 20. Gao X, Zhang H, Takahashi T, Hsieh J, Liao J, Steinberg GK, et al. The Akt sig-
naling pathway contributes to postconditioning’s protection against stroke;
the protection is associated with the MAPK and PKC pathways. J Neurochem
(2008) 105:943–55. doi:10.1111/j.1471-4159.2008.05218.x 1. Perry VH, Newman TA, Cunningham C. The impact of systemic infection
on the progression of neurodegenerative disease. Nat Rev Neurosci (2003)
4:103–12. doi:10.1038/nrn1032 21. O’Riordan KJ, Huang IC, Pizzi M, Spano P, Boroni F, Egli R, et al. Regulation
of nuclear factor κB in the hippocampus by group I metabotropic
glutamate receptors. J Neurosci (2006) 2006(26):4870–9. doi:10.1523/
JNEUROSCI.4527-05.2006 2. Noble W, Garwood CJ, Hanger DP. Minocycline as a potential therapeutic
agent in neurodegenerative disorders characterised by protein misfolding. Prion (2009) 3:78–83. doi:10.4161/pri.3.2.8820 3. Stirling DP, Koochesfahani KM, Steeves JD, Tetzlaff W. Minocycline as a
neuroprotective agent. Neuroscientist (2005) 11:308–22. doi:10.1177/1073
858405275175 22. Switzer JA, Hess DC, Ergul A, Waller JL, Machado LS, Portik-Dobos V,
et al. Matrix metalloproteinase-9 in an exploratory trial of intravenous
minocycline for acute ischemic stroke. Stroke (2011) 42:2633–5. doi:10.1161/
STROKEAHA.111.618215 4. Zhou H, Lapointe BM, Clark SR, Zbytnuik L, Kubes P. A requirement
for microglial TLR4 in leukocyte recruitment into brain in response to
lipopolysaccharide. J Immunol (2006) 177:8103–10. doi:10.4049/jimmunol. 177.11.8103 23. Foteinou PT, Calvano SE, Lowry SF, Androulakis IP. In silico simulation
of corticosteroids effect on an NFkB-dependent physicochemical model
of systemic inflammation. PLoS One (2009) 4:e4706. doi:10.1371/journal. pone.0004706 5. Huang WC, Qiao Y, Xu L, Kacimi R, Sun X, Giffard RG, et al. Direct protec-
tion of cultured neurons from ischemia-like injury by minocycline. Anat Cell
Biol (2010) 43:325–31. doi:10.5115/acb.2010.43.4.325 24. Wang HY, Crupi D, Liu J, Stucky A, Cruciata G, Di Rocco A, et al. Repetitive
transcranial magnetic stimulation enhances BDNF-TrkB signaling in
both brain and lymphocyte. J Neurosci (2011) 31:11044–54. doi:10.1523/
JNEUROSCI.2125-11.2011 6. Dunston CR, Griffiths HR, Lambert PA, Staddon S, Vernallis AB. Proteomic
analysis of the anti-inflammatory action of minocycline. Proteomics (2011)
11:42–51. doi:10.1002/pmic.201000273 25. Fritsch B, Reis J, Martinowich K, Schambra HM, Ji Y, Cohen LG, et al. Direct
current stimulation promotes BDNF-dependent synaptic plasticity: potential
implications for motor learning. Neuron (2010) 66:198–204. doi:10.1016/j. neuron.2010.03.035 7. Yenari MA, Xu L, Tang XN, Qiao Y, Giffard RG. Microglia potentiate damage
to blood-brain barrier constituents: improvement by minocycline in vivo and
in vitro. Stroke (2006) 37:1087–93. doi:10.1161/01.STR.0000206281.77178.ac 26. Lipniacki T, Paszek P, Brasier AR, Luxon B, Kimmel M. FUNDING Glue – Grant Scheme and Tata Innovation Program, Department
of Biotechnology, Government of India; Department of
Information Technology, Government of India; and National
Brain Research Centre for supporting this work. Glue – Grant Scheme and Tata Innovation Program, Department
of Biotechnology, Government of India; Department of
Information Technology, Government of India; and National
Brain Research Centre for supporting this work. June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 10 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. REFERENCES Neurotrophin-evoked
rapid excitation through TrkB receptors. Nature (1999) 401:918–21. doi:10.1038/44847 59. Biondi RM, Cheung PC, Casamayor A, Deak M, Currie RA, Alessi DR. Identification of a pocket in the PDK1 kinase domain that interacts with PIF
and the C-terminal residues of PKA. EMBO J (2000) 19:979–88. doi:10.1093/
emboj/19.5.979 40. Atwal JK, Massie B, Miller FD, Kaplan DR. The TrkB-Shc site signals neuro-
nal survival and local axon growth via MEK and P13-kinase. Neuron (2000)
27:265–77. doi:10.1016/S0896-6273(00)00035-0 60. Gottschalk WA, Jiang H, Tartaglia N, Feng L, Figurov A, Lu B. Signaling
mechanisms mediating BDNF modulation of synaptic plasticity in the
hippocampus. Learn Mem (1999) 6:243–56. 41. Aksan I, Kurnaz ML. A computer-based model for the regulation of mitogen
activated protein kinase (MAPK) activation. J Recept Signal Transduct Res
(2003) 23:197–209. doi:10.1081/RRS-120025203 61. Mai L, Jope RS, Li X. BDNF-mediated signal transduction is modulated
by GSK3beta and mood stabilizing agents. J Neurochem (2002) 82:75–83. doi:10.1046/j.1471-4159.2002.00939.x 42. Hayakawa-Yano Y, Nishida K, Fukami S, Gotoh Y, Hirano T, Nakagawa T,
et al. Epidermal growth factor signaling mediated by grb2 associated binder1
is required for the spatiotemporally regulated proliferation of olig2-express-
ing progenitors in the embryonic spinal cord. Stem Cells (2007) 25:1410–22. doi:10.1634/stemcells.2006-0584 j
62. Dijkhuizen PA, Ghosh A. BDNF regulates primary dendrite formation in
cortical neurons via the PI3-kinase and MAP kinase signaling pathways. J Neurobiol (2005) 62:278–88. doi:10.1002/neu.20100 h 63. Zu YL, Wu F, Gilchrist A, Ai Y, Labadia ME, Huang CK. The primary struc-
ture of a human MAP kinase activated protein kinase 2. Biochem Biophys Res
Commun (1994) 200:1118–24. doi:10.1006/bbrc.1994.1566 43. Ma L, Janetopoulos C, Yang L, Devreotes PN, Iglesias PA. Two complementary,
local excitation, global inhibition mechanisms acting in parallel can explain
the chemoattractant-induced regulation of PI(3,4,5)P3 response in dictyos-
telium cells. Biophys J (2004) 87:3764–74. doi:10.1529/biophysj.104.045484 i 64. Sabers CJ, Martin MM, Brunn GJ, Williams JM, Dumont FJ, Wiederrecht
G, et al. Isolation of a protein target of the FKBP12-rapamycin complex in
mammalian cells. J Biol Chem (1995) 270:815–22. doi:10.1074/jbc.270.2.815 44. Chodniewicz D, Alteraifi AM, Zhelev DV. Experimental evidence for the
limiting role of enzymatic reactions in chemoattractant-induced pseudo-
pod extension in human neutrophils. J Biol Chem (2004) 279:24460–6. doi:10.1074/jbc.M312764200 65. Jakubowicz T, Leader DP. Activation of a ribosomal protein S6 kinase in
mouse fibroblasts during infection with herpesvirus. Eur J Biochem (1987)
168:371–6. doi:10.1111/j.1432-1033.1987.tb13429.x 66. Haystead TA, Haystead CM, Hu C, Lin TA, Lawrence JC Jr. REFERENCES Regulated phosphorylation and low
abundance of HeLa cell initiation factor eIF-4F suggest a role in translational
control. Heat shock effects on eIF-4F. J Biol Chem (1987) 262:380–8. 52. Carpenter CL, Duckworth BC, Auger KR, Cohen B, Schaffhausen BS, Cantley
LC. Purification and characterization of phosphoinositide 3-kinase from rat
liver. J Biol Chem (1990) 265:19704–11. 72. Eberwine J, Miyashiro K, Kacharmina JE, Job C. Local translation of classes
of mRNAs that are targeted to neuronal dendrites. Proc Natl Acad Sci U S A
(2001) 98:7080–5. doi:10.1073/pnas.121146698 p
73. Burnett PE, Barrow RK, Cohen NA, Snyder SH, Sabatini DM. RAFT1 phos-
phorylation of the translational regulators p70 S6 kinase and 4E-BP1. Proc
Natl Acad Sci U S A (1998) 95:1432–7. doi:10.1073/pnas.95.4.1432 53. Koh G, Teong HF, Clement MV, Hsu D, Thiagarajan PS. A decompositional
approach to parameter estimation in pathway modeling: a case study of
the Akt and MAPK pathways and their crosstalk. Bioinformatics (2006)
22:e271–80. doi:10.1093/bioinformatics/btl264 74. Karim MM, Hughes JM, Warwicker J, Scheper GC, Proud CG, McCarthy JE. A quantitative molecular model for modulation of mammalian translation by
the eIF4E-binding protein 1. J Biol Chem (2001) 276:20750–7. doi:10.1074/
jbc.M011068200 54. Alessi DR, Cohen P. Mechanism of activation and function of protein kinase
B. Curr Opin Genet Dev (1998) 8:55–62. doi:10.1016/S0959-437X(98)80062-2 55. Barnett SF, Defeo-Jones D, Fu S, Hancock PJ, Haskell KM, Jones RE, et al. Identification and characterization of pleckstrin-homology-domain-depen-
dent and isoenzyme-specific Akt inhibitors. Biochem J (2005) 385:399–408. doi:10.1042/BJ20041140 75. Ptushkina M, von der Haar T, Karim MM, Hughes JM, McCarthy JE. Repressor binding to a dorsal regulatory site traps human eIF4E in a high
cap-affinity state. EMBO J (1999) 18:4068–75. doi:10.1093/emboj/18.14.4068 f fi
76. Gingras AC, Raught B, Sonenberg N. eIF4 initiation factors: effectors of
mRNA recruitment to ribosomes and regulators of translation. Annu Rev
Biochem (1999) 68:913–63. doi:10.1146/annurev.biochem.68.1.913 56. Kikuchi S, Fujimoto K, Kitagawa N, Fuchikawa T, Abe M, Oka K, et al. Kinetic simulation of signal transduction system in hippocampal long-term
potentiation with dynamic modeling of protein phosphatase 2A. Neural Netw
(2003) 16:1389–98. doi:10.1016/j.neunet.2003.09.002 h 77. von der Haar T, Hughes JM, Manjarul Karim M, Ptushkina M, McCarthy
JE. Translation initiation and surface plasmon resonance: new technology
applied to old questions. Biochem Soc Trans (2002) 30:155–62. doi:10.1042/
bst0300155 57. Geist RT, Gutmann DH. The tuberous sclerosis 2 gene is expressed at high
levels in the cerebellum and developing spinal cord. Cell Growth Differ (1995)
6:1477–83. REFERENCES Phosphorylation
of PHAS-I by mitogen-activated protein (MAP) kinase. Identification of a
site phosphorylated by MAP kinase in vitro and in response to insulin in rat
adipocytes. J Biol Chem (1994) 269:23185–91. 45. Yamada KM, Araki M. Tumor suppressor PTEN: modulator of cell signaling,
growth, migration and apoptosis. J Cell Sci (2001) 114:2375–82. h 46. Lee FS, Kim AH, Khursigara G, Chao MV. The uniqueness of being a
neurotrophin receptor. Curr Opin Neurobiol (2001) 11:281–6. doi:10.1016/
S0959-4388(00)00209-9 67. Toral-Barza L, Zhang WG, Lamison C, Larocque J, Gibbons J, Yu K. Characterization of the cloned full-length and a truncated human target
of rapamycin: activity, specificity, and enzyme inhibition as studied by a
high capacity assay. Biochem Biophys Res Commun (2005) 332:304–10. doi:10.1016/j.bbrc.2005.04.117 h 47. Barde YA. Neurobiology: neurotrophin channels excitement. Nature (2002)
419:683–4. doi:10.1038/419683a 48. Barnea A, Roberts J, Croll SD. Continuous exposure to brain-derived neuro-
trophic factor is required for persistent activation of TrkB receptor, the ERK
signaling pathway, and the induction of neuropeptide Y production in cortical
cultures. Brain Res (2004) 1020:106–17. doi:10.1016/j.brainres.2004.06.018 68. Flotow H, Thomas G. Substrate recognition determinants of the mitogen-ac-
tivated 70K S6 kinase from rat liver. J Biol Chem (1992) 267:3074–8. i 49. Obermeier A, Lammers R, Wiesmuller KH, Jung G, Schlessinger J, Ullrich
A. Identification of Trk binding sites for SHC and phosphatidylinositol
3’-kinase and formation of a multimeric signaling complex. J Biol Chem
(1993) 268:22963–6. 69. Zhang WG, Shor B, Yu K. Identification and characterization of a consti-
tutively T-loop phosphorylated and active recombinant S6K1: expression,
purification, and enzymatic studies in a high capacity non-radioactive
TR-FRET Lance assay. Protein Expr Purif (2006) 46:414–20. doi:10.1016/j. pep.2005.08.012 50. Laminet AA, Apell G, Conroy L, Kavanaugh WM. Affinity, specificity, and
kinetics of the interaction of the SHC phosphotyrosine binding domain with
asparagine-X-X-phosphotyrosine motifs of growth factor receptors. J Biol
Chem (1996) 271:264–9. doi:10.1074/jbc.271.1.264 70. McKendrick L, Morley SJ, Pain VM, Jagus R, Joshi B. Phosphorylation
of eukaryotic initiation factor 4E (eIF4E) at Ser209 is not required for
protein synthesis in vitro and in vivo. Eur J Biochem (2001) 268:5375–85. doi:10.1046/j.0014-2956.2001.02478.x 51. Pacold ME, Suire S, Perisic O, Lara-Gonzalez S, Davis CT, Walker EH,
et al. Crystal structure and functional analysis of Ras binding to its effector
phosphoinositide 3-kinase gamma. Cell (2000) 103:931–43. doi:10.1016/
S0092-8674(00)00196-3 71. Duncan R, Milburn SC, Hershey JW. REFERENCES Immunopurified mammalian target of rapamycin phosphorylates and
activates p70 S6 kinase alpha in vitro. J Biol Chem (1999) 274:34493–8. doi:10.1074/jbc.274.48.34493 33. Alessi DR, Kozlowski MT, Weng QP, Morrice N, Avruch J. 3-Phosphoinositide-
dependent protein kinase 1 (PDK1) phosphorylates and activates the
p70 S6 kinase in vivo and in vitro. Curr Biol (1998) 8:69–81. doi:10.1016/
S0960-9822(98)70037-5 15. Barone FC, Irving EA, Ray AM, Lee JC, Kassis S, Kumar S, et al. Inhibition of p38 mitogen-activated protein kinase provides neuro-
protection in cerebral focal ischemia. Med Res Rev (2001) 21:129–45. doi:10.1002/1098-1128(200103)21:2<129::AID-MED1003>3.0.CO;2-H i 34. Worley PF, Baraban JM, Snyder SH. Inositol 1,4,5-trisphosphate receptor
binding: autoradiographic localization in rat brain. J Neurosci (1989)
9:339–46. 16. Wang X, Wang H, Xu L, Rozanski DJ, Sugawara T, Chan PH, et al. Significant
neuroprotection against ischemic brain injury by inhibition of the MEK1
protein kinase in mice: exploration of potential mechanism associated
with apoptosis. J Pharmacol Exp Ther (2003) 304:172–8. doi:10.1124/
jpet.102.040246 35. Redpath NT, Price NT, Severinov KV, Proud CG. Regulation of elongation
factor-2 by multisite phosphorylation. Eur J Biochem (1993) 213:689–99. doi:10.1111/j.1432-1033.1993.tb17809.x 17. Maddahi A, Edvinsson L. Enhanced expressions of microvascular smooth
muscle receptors after focal cerebral ischemia occur via the MAPK MEK/
ERK pathway. BMC Neurosci (2008) 9:85. doi:10.1186/1471-2202-9-85 36. Wang X, Li W, Williams M, Terada N, Alessi DR, Proud CG. Regulation of
elongation factor 2 kinase by p90(RSK1) and p70 S6 kinase. EMBO J (2001)
20:4370–9. doi:10.1093/emboj/20.16.4370 18. Pang T, Wang J, Benicky J, Saavedra JM. Minocycline ameliorates LPS-induced
inflammation in human monocytes by novel mechanisms including LOX-1,
Nur77 and LITAF inhibition. Biochim Biophys Acta (2012) 1820:503–10. doi:10.1016/j.bbagen.2012.01.011 37. Mitsui K, Brady M, Palfrey HC, Nairn AC. Purification and characterization
of calmodulin-dependent protein kinase III from rabbit reticulocytes and rat
pancreas. J Biol Chem (1993) 268:13422–33. 19. Qi ZF, Luo YM, Liu XR, Wang RL, Zhao HP, Yan F, et al. AKT/GSK3β-
dependent autophagy contributes to the neuroprotection of limb remote
ischemic postconditioning in the transient cerebral ischemic rat model. CNS
Neurosci Ther (2012) 18:965–73. doi:10.1111/cns.12016 38. Parkhurst KM, Hileman RE, Saha D, Gupta NK, Parkhurst LJ. Thermodynamic
characterization of the cooperativity of 40S complex formation during the
initiation of eukaryotic protein synthesis. Biochemistry (1994) 33:15168–77. doi:10.1021/bi00254a028 June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 11 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. 39. Kafitz KW, Rose CR, Thoenen H, Konnerth A. REFERENCES i 78. Scheper GC, van Kollenburg B, Hu J, Luo Y, Goss DJ, Proud CG. Phosphorylation of eukaryotic initiation factor 4E markedly reduces its
affinity for capped mRNA. J Biol Chem (2002) 277:3303–9. doi:10.1074/jbc. M103607200 58. James SR, Downes CP, Gigg R, Grove SJ, Holmes AB, Alessi DR. Specific
binding of the Akt-1 protein kinase to phosphatidylinositol 3,4,5-tris-
phosphate without subsequent activation. Biochem J (1996) 315:709–13. doi:10.1042/bj3150709 June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 12 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. for treatment of psychiatric disorders. In: Marcolin MA, Padberg F, editors. Advances in Biological Psychiatry Basel. (Vol. 23), Munich: Karger (2007). p. 172–86. 79. Marin P, Nastiuk KL, Daniel N, Girault JA, Czernik AJ, Glowinski J, et al. Glutamate-dependent phosphorylation of elongation factor-2 and inhibition
of protein synthesis in neurons. J Neurosci (1997) 17:3445–54. 97. Mahmoudi H, Borhani Haghighi A, Petramfar P, Jahanshahi S, Salehi Z,
Fregni F. Transcranial direct current stimulation: electrode montage in
stroke. Disabil Rehabil (2011) 33:1383–8. doi:10.3109/09638288.2010. 532283 80. Ryazanov AG. Ca2+/calmodulin-dependent phosphorylation of elongation
factor 2. FEBS Lett (1987) 214:331–4. doi:10.1016/0014-5793(87)80081-9 81. Fagan SC, Waller JL, Nichols FT, Edwards DJ, Pettigrew LC, Clark WM, et al. Minocycline to improve neurologic outcome in stroke (MINOS): a dose-find-
ing study. Stroke (2010) 41:2283–7. doi:10.1161/STROKEAHA.110.582601 98. Zhang SX, Zhang JP, Fletcher DL, Zoeller RT, Sun GY. In situ hybridization
of mRNA expression for IP3 receptor and IP3-3-kinase in rat brain after
transient focal cerebral ischemia. Brain Res Mol Brain Res (1995) 32:252–60. doi:10.1016/0169-328X(95)00085-7 82. Jung YJ, Isaacs JS, Lee S, Trepel J, Neckers L. IL-1beta-mediated up-regulation
of HIF-1alpha via an NFkappaB/COX-2 pathway identifies HIF-1 as a critical
link between inflammation and oncogenesis. FASEB J (2003) 17:2115–7. doi:10.1096/fj.03-0329fje 99. Sun GY, Zhang JP, Lin TA, Lin TN, He YY, Hsu CY. Inositol trisphosphate,
polyphosphoinositide turnover, and high-energy metabolites in focal cere-
bral ischemia and reperfusion. Stroke (1995) 26:1893–900. doi:10.1161/01. STR.26.10.1893 jj
83. Ricciotti E, FitzGerald GA. Prostaglandins and inflammation. Arterioscler
Thromb Vasc Biol (2011) 31:986–1000. doi:10.1161/ATVBAHA.110.207449 h
84. Lee SM, Yune TY, Kim SJ, Kim YC, Oh YJ, Markelonis GJ, et al. Minocycline
inhibits apoptotic cell death via attenuation of TNF-alpha expression follow-
ing iNOS/NO induction by lipopolysaccharide in neuron/glia co-cultures. J Neurochem (2004) 91:568–78. doi:10.1111/j.1471-4159.2004.02780.x 100. Nizar K, Uhlirova H, Tian P, Saisan PA, Cheng Q, Reznichenko L, et al. REFERENCES In vivo stimulus-induced vasodilation occurs without IP3 receptor activation
and may precede astrocytic calcium increase. J Neurosci (2013) 33:8411–22. doi:10.1523/JNEUROSCI.3285-12.2013 85. Liu T, Clark RK, McDonnell PC, Young PR, White RF, Barone FC, et al. Tumor necrosis factor-alpha expression in ischemic neurons. Stroke (1994)
25:1481–8. doi:10.1161/01.STR.25.7.1481 101. Lu Y, Christian K, Lu B. BDNF: a key regulator for protein synthesis-depen-
dent LTP and long-term memory? Neurobiol Learn Mem (2008) 89:312–23. doi:10.1016/j.nlm.2007.08.018 86. Siao CJ, Fernandez SR, Tsirka SE. Cell type-specific roles for tissue plas-
minogen activator released by neurons or microglia after excitotoxic injury. J Neurosci (2003) 23:3234–42. doi: 0270-6474/03/233234-09$15.00/0 102. Sanhueza M, Lisman J. The CaMKII/NMDAR complex as a molecular
memory. Mol Brain (2013) 6:10. doi:10.1186/1756-6606-6-10 87. Gasche Y, Fujimura M, Morita-Fujimura Y, Copin JC, Kawase M,
Massengale J, et al. Early appearance of activated matrix metalloprotein-
ase-9 after focal cerebral ischemia in mice: a possible role in blood-brain
barrier dysfunction. J Cereb Blood Flow Metab (1999) 19:1020–8. doi:10.1097/00004647-199909000-00010 103. Ma J, Zhang Z, Kang L, Geng D, Wang Y, Wang M, et al. Repetitive transcra-
nial magnetic stimulation (rTMS) influences spatial cognition and modulates
hippocampal structural synaptic plasticity in aging mice. Exp Gerontol (2014)
58:256–68. doi:10.1016/j.exger.2014.08.011 t 104. Yoon KJ, Lee YT, Han TR. Mechanism of functional recovery after repet-
itive transcranial magnetic stimulation (rTMS) in the subacute cerebral
ischemic rat model: neural plasticity or anti-apoptosis? Exp Brain Res (2011)
214:549–56. doi:10.1007/s00221-011-2853-2 88. Clark AW, Krekoski CA, Bou SS, Chapman KR, Edwards DR. Increased
gelatinase A (MMP-2) and gelatinase B (MMP-9) activities in human
brain after focal ischemia. Neurosci Lett (1997) 238:53–6. doi:10.1016/
S0304-3940(97)00859-8 105. Di Lazzaro V, Profice P, Pilato F, Dileone M, Oliviero A, Ziemann
U. The effects of motor cortex rTMS on corticospinal descending
activity. Clin
Neurophysiol
(2010)
121:464–73. doi:10.1016/j. clinph.2009.11.007 89. Gu Z, Cui J, Brown S, Fridman R, Mobashery S, Strongin AY, et al. A highly
specific inhibitor of matrix metalloproteinase-9 rescues laminin from
proteolysis and neurons from apoptosis in transient focal cerebral ischemia. J Neurosci (2005) 25:6401–8. doi:10.1523/JNEUROSCI.1563-05.2005 106. Hummel FC, Cohen LG. Non-invasive brain stimulation: a new strategy to
improve neurorehabilitation after stroke? Lancet Neurol (2006) 5:708–12. doi:10.1016/S1474-4422(06)70525-7 90. Lapchak PA, Chapman DF, Zivin JA. Metalloproteinase inhibition reduces
thrombolytic (tissue plasminogen activator)-induced hemorrhage after
thromboembolic stroke. Stroke (2000) 31:3034–40. doi:10.1161/01.STR.31. 12.3034 107. Abel Zur, Wiesch P, Abel S, Gkotzis S, Ocampo P, Engelstädter J, et al. APPENDIX Chemical reactions for BDNF and TrKB signaling
y(1) = BDNF + TrKB → BDNF_TrKB_clx
% Lig
y(2) = BDNF_TrKB_clx + TrKB →
BDNF_TrKB2_clx
% Re
y(3) = BDNF_TrKB2_clx → BDNF_TrKB2*_clx
% Au
y(4) = BDNF_TrKB2*_clx ⇒
Int_BDNF_TrKB2*_clx
% Re
y(5) = Int_BDNF_TrKB2*_clx → TrKB
% Re
y(6) = Shc + BDNF_TrKB2*_clx → BDNF_
TrKB2*_clx + Shc*
% Sh
y(7) = Shc* → Shc
% De
y(8) = PLC-γ + BDNF_TrKB2*_clx → BDNF_
TrKB2*_clx + PLC-γ*
% PL
y(9) = PLC-γ + PLC-γ_basal → PLC-γ_basal
+ PLC-γ*
% PL
y(10) = PLC-γ* → PLC-γ
% De
y(11) = Grb2 + Shc* → Shc*-Grb2
% Grb
y(12) = Shc*-Grb2 + Gab1 →
Shc*_Grb2_Gab1
% For
y(13) = Shc*_Grb2_Gab1 + PI3K →
Shc*_Grb2_Gab1_PI3K_clx
%PI3
Gab1
y(14) = Ras-GTP + PI3K → Ras-GTP_PI3K
% PI3
y(15) = PIP2 + Shc*_Grb2_Gab1_PI3K_clx
→ Shc*_Grb2_Gab1_PI3K_clx + PIP3
% For
y(16) = PIP3 + PTEN → PTEN + PIP2
% For
y(17) = PI3K → PI3K_basal
% For
y(18) = PIP2 + PI3K_basal → PI3K_basal
% Ba
y(19) = PIP3 + PDK1 → PIP3_PDK1
% PD
y(20) = PIP3 + AKT → PIP3_AKT
% AK
y(21) = PIP3_AKT + PIP3_PDK1 → PIP3_
PDK1 + PIP3_AKT_thr308
% Pa
y(22) = PIP3_AKT_thr308 + PP2A → PP2A +
PIP3_AKT
% De
y(23) = PIP3_AKT_thr308 + PIP3_PDK2 →
PIP3_PDK2 + PIP3_AKT_t308_s473
%Full
y(24) = PIP3_AKT_t308_s473 + PP2A →
PIP3_AKT_thr308 + PP2A
% De
y(25) = TSC1–TSC2 + PIP3_AKT_t308_s473
→ PIP3_AKT_t308_s473 + TSC1–TSC2*
%Pho
y(26) = TSC1–TSC2* → TSC1–TSC2
% De
TSC1
y(27) = Rheb-GTP + TSC1–TSC2 → TSC1–
TSC2 + Rheb-GDP
% Hy
TSC1
y(28) = Rheb-GDP → Rheb-GTP
% Co
Rheb
y(29) = IP3R + IP3 → IP3RIP3
% IP3
forma
y(30) = IP3RIP3 + IP3 → IP3R2IP3
% IP3
and fo
y(31) = IP3R2IP3 + IP3 → IP3R3IP3
%IP3
and fo
y(32) = IP3R3IP3 + Ca2 → IP3R3IP3 +
Ca(cyt)
%IP3
Ca2+ a
and C TABLE A1 | Chemical species for Module 1. |
p
x(1)
IKKn neutral
x(2)
IKKa active
x(3)
IKKi inactive
x(4)
(IKKa|IkBa)
x(5)
(IKKa|IkBa|NFkB)
x(6)
NFkB
x(7)
NFkBn
x(8)
PTGS2
x(9)
PTGS2 transcription
x(10)
IkBa
x(11)
IkBan
x(12)
IkBat
x(13)
(IkBa|NFkB) cytoplasmic
x(14)
(IkBan|NFkBn) nuclear
x(15)
Control early gene TABLE A2 | The following association and dissociation rate constants for
module I are taken from Ref. (23, 26). REFERENCES y(1) = BDNF + TrKB → BDNF_TrKB_clx
% Ligand Binding
y(2) = BDNF_TrKB_clx + TrKB →
BDNF_TrKB2_clx
% Receptor dimerization
y(3) = BDNF_TrKB2_clx → BDNF_TrKB2*_clx
% Autophosphorylation
y(4) = BDNF_TrKB2*_clx ⇒
Int_BDNF_TrKB2*_clx
% Receptor Internalization
y(5) = Int_BDNF_TrKB2*_clx → TrKB
% Receptor Cycling
y(6) = Shc + BDNF_TrKB2*_clx → BDNF_
TrKB2*_clx + Shc*
% Shc Phosphorylation
y(7) = Shc* → Shc
% Dephosphorylation Shc*
y(8) = PLC-γ + BDNF_TrKB2*_clx → BDNF_
TrKB2*_clx + PLC-γ*
% PLC-γ Phosphorylation
y(9) = PLC-γ + PLC-γ_basal → PLC-γ_basal
+ PLC-γ*
% PLC-γ basal Phosphorylation
y(10) = PLC-γ* → PLC-γ
% Dephosphorylation of PLC-γ
y(11) = Grb2 + Shc* → Shc*-Grb2
% Grb2 binding Shc*
y(12) = Shc*-Grb2 + Gab1 →
Shc*_Grb2_Gab1
% Formation of Shc*_Grb2_Gab1
y(13) = Shc*_Grb2_Gab1 + PI3K →
Shc*_Grb2_Gab1_PI3K_clx
%PI3K activation by Shc_Grb2_
Gab1 complex
y(14) = Ras-GTP + PI3K → Ras-GTP_PI3K
% PI3K activation by Ras-GTP
y(15) = PIP2 + Shc*_Grb2_Gab1_PI3K_clx
→ Shc*_Grb2_Gab1_PI3K_clx + PIP3
% Formation of PIP3
y(16) = PIP3 + PTEN → PTEN + PIP2
% Formation of PIP2
y(17) = PI3K → PI3K_basal
% Formation of basal PIP3
y(18) = PIP2 + PI3K_basal → PI3K_basal
% Basal PI3K activity
y(19) = PIP3 + PDK1 → PIP3_PDK1
% PDK1 translocation
y(20) = PIP3 + AKT → PIP3_AKT
% AKT translocation
y(21) = PIP3_AKT + PIP3_PDK1 → PIP3_
PDK1 + PIP3_AKT_thr308
% Partial AKT activation (Thr308)
y(22) = PIP3_AKT_thr308 + PP2A → PP2A +
PIP3_AKT
% Dephosphorylation of AKT*
y(23) = PIP3_AKT_thr308 + PIP3_PDK2 →
PIP3_PDK2 + PIP3_AKT_t308_s473
%Fully AKT activation (Ser473)
y(24) = PIP3_AKT_t308_s473 + PP2A →
PIP3_AKT_thr308 + PP2A
% Dephosphorylation of AKT**
y(25) = TSC1–TSC2 + PIP3_AKT_t308_s473
→ PIP3_AKT_t308_s473 + TSC1–TSC2*
%Phosphorylation of TSC1,2
y(26) = TSC1–TSC2* → TSC1–TSC2
% Dephosphorylation of
TSC1–TSC2*
y(27) = Rheb-GTP + TSC1–TSC2 → TSC1–
TSC2 + Rheb-GDP
% Hydrolysis of Rheb-GTP by
TSC1–TSC2
y(28) = Rheb-GDP → Rheb-GTP
% Conversion of Rheb-GDP to
Rheb-GTP
y(29) = IP3R + IP3 → IP3RIP3
% IP3R interaction with IP3 and
formation of IP3RIP3
y(30) = IP3RIP3 + IP3 → IP3R2IP3
% IP3RIP3interaction with IP3
and formation of IP3R2IP3
y(31) = IP3R2IP3 + IP3 → IP3R3IP3
%IP3R2IP3interaction with IP3
and formation of IP3R3IP3
y(32) = IP3R3IP3 + Ca2 → IP3R3IP3 +
Ca(cyt)
%IP3R3IP3 interaction with
Ca2+ and formation of IP3R3IP3
and Ca2+ Chemical reactions for BDNF and TrKB signaling pathways (Module 2). REFERENCES Classic
reaction kinetics can explain complex patterns of antibiotic action. Sci Transl
Med (2015) 7:287ra273. doi:10.1126/scitranslmed.aaa8760 91. Machado LS, Kozak A, Ergul A, Hess DC, Borlongan CV, Fagan SC. Delayed minocycline inhibits ischemia-activated matrix metalloproteinases
2 and 9 after experimental stroke. BMC Neurosci (2006) 7:56. doi:10.1186/
1471-2202-7-56 108. Geva-Zatorsky N, Dekel E, Cohen AA, Danon T, Cohen L, Alon U. Protein
dynamics in drug combinations: a linear superposition of individual-drug
responses. Cell (2010) 140:643–51. doi:10.1016/j.cell.2010.02.011 92. Blum D, Chtarto A, Tenenbaum L, Brotchi J, Levivier M. Clinical potential
of minocycline for neurodegenerative disorders. Neurobiol Dis (2004)
17:359–66. doi:10.1016/j.nbd.2004.07.012 109. Clermont G, Bartels J, Kumar R, Constantine G, Vodovotz Y, Chow C. In
silico design of clinical trials: a method coming of age. Crit Care Med (2004)
32:2061–70. doi:10.1097/01.CCM.0000142394.28791.C3 93. Gordon PH, Moore DH, Miller RG, Florence JM, Verheijde JL, Doorish C,
et al. Efficacy of minocycline in patients with amyotrophic lateral sclerosis:
a phase III randomised trial. Lancet Neurol (2007) 6:1045–53. doi:10.1016/
S1474-4422(07)70270-3 Conflict of Interest Statement: The authors declare that the research was con-
ducted in the absence of any commercial or financial relationships that could be
construed as a potential conflict of interest. Conflict of Interest Statement: The authors declare that the research was con-
ducted in the absence of any commercial or financial relationships that could be
construed as a potential conflict of interest. 94. Lampl Y, Boaz M, Gilad R, Lorberboym M, Dabby R, Rapoport A, et al. Minocycline treatment in acute stroke: an open-label, evaluator-blinded study. Neurology (2007) 69:1404–10. doi:10.1212/01.wnl.0000277487.04281.db Copyright © 2016 Alam, Subramanyam Rallabandi and Roy. This is an open-ac-
cess article distributed under the terms of the Creative Commons Attribution
License (CC BY). The use, distribution or reproduction in other forums is
permitted, provided the original author(s) or licensor are credited and that the
original publication in this journal is cited, in accordance with accepted academic
practice. No use, distribution or reproduction is permitted which does not comply
with these terms. 95. Srivastava MVP, Bhasin A, Bhatia R, Garg A, Gaikwad S, Prasad K, et al. Efficacy of minocycline in acute ischemic stroke: a single-blinded, placebo-
controlled trial. Neurol India (2012) 60:23–8. doi:10.4103/0028-3886.93584 96. Nitsche M, Antal A, Paulus W. REFERENCES Induction and modulation of neuroplasticity
by transcranial direct current stimulation, transcranial brain stimulation June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 13 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. In Silico Mode
Chemical reactions for BDNF and TrKB
y(1) = BDNF + TrKB → BDNF_TrKB_clx
y(2) = BDNF_TrKB_clx + TrKB →
BDNF_TrKB2_clx
y(3) = BDNF_TrKB2_clx → BDNF_TrKB2*_clx
y(4) = BDNF_TrKB2*_clx ⇒
Int_BDNF_TrKB2*_clx
y(5) = Int_BDNF_TrKB2*_clx → TrKB
y(6) = Shc + BDNF_TrKB2*_clx → BDNF_
TrKB2*_clx + Shc*
y(7) = Shc* → Shc
y(8) = PLC-γ + BDNF_TrKB2*_clx → BDNF_
TrKB2*_clx + PLC-γ*
y(9) = PLC-γ + PLC-γ_basal → PLC-γ_basal
+ PLC-γ*
y(10) = PLC-γ* → PLC-γ
y(11) = Grb2 + Shc* → Shc*-Grb2
y(12) = Shc*-Grb2 + Gab1 →
Shc*_Grb2_Gab1
y(13) = Shc*_Grb2_Gab1 + PI3K →
Shc*_Grb2_Gab1_PI3K_clx
y(14) = Ras-GTP + PI3K → Ras-GTP_PI3K
y(15) = PIP2 + Shc*_Grb2_Gab1_PI3K_clx
→ Shc*_Grb2_Gab1_PI3K_clx + PIP3
y(16) = PIP3 + PTEN → PTEN + PIP2
y(17) = PI3K → PI3K_basal
y(18) = PIP2 + PI3K_basal → PI3K_basal
y(19) = PIP3 + PDK1 → PIP3_PDK1
y(20) = PIP3 + AKT → PIP3_AKT
y(21) = PIP3_AKT + PIP3_PDK1 → PIP3_
PDK1 + PIP3_AKT_thr308
y(22) = PIP3_AKT_thr308 + PP2A → PP2A +
PIP3_AKT
y(23) = PIP3_AKT_thr308 + PIP3_PDK2 →
PIP3_PDK2 + PIP3_AKT_t308_s473
y(24) = PIP3_AKT_t308_s473 + PP2A →
PIP3_AKT_thr308 + PP2A
y(25) = TSC1–TSC2 + PIP3_AKT_t308_s473
→ PIP3_AKT_t308_s473 + TSC1–TSC2*
y(26) = TSC1–TSC2* → TSC1–TSC2
y(27) = Rheb-GTP + TSC1–TSC2 → TSC1–
TSC2 + Rheb-GDP
y(28) = Rheb-GDP → Rheb-GTP
y(29) = IP3R + IP3 → IP3RIP3
y(30) = IP3RIP3 + IP3 → IP3R2IP3
y(31) = IP3R2IP3 + IP3 → IP3R3IP3
y(32) = IP3R3IP3 + Ca2 → IP3R3IP3 +
Ca(cyt) Chemical reactions for BDNF and TrKB signaling pathways (Module 2). APPENDIX y(33) = CaM-Ca4 + CAMKIII →
CaMKIII_CaM-Ca4
% Binding of Calmodulin-Calcium
to CaMKIII
y(34) = CaMKIII_CaM-Ca4 + eEF2 →
eEF2thr-56 + CaMKIII_CaM-Ca4
% Phosphorylation of eEF2
y(35) = eEF2thr-56 + PP2A → eEF2 + PP2A
% Dephosphorylation of
eEF2thr-56
y(36) = CaMKIII + S6K_thr-252 → CaMKIII* +
S6K_thr-252
% Phosphorylation of CaMKIII
y(37) = CaMKIII + S6K_Basal → CaMKIII* +
S6K_thr-252
% Basal activation of CaMKIII
TABLE A3 | Chemical species and initial concentration for Module 2. y1(0)
BDNF
0.1 nM
y2(0)
TrKB
0.25 μM
y3(0)
Int_BDNF_TrKB2*_clx
0.25 μM
y6(0)
Shc
0.5 μM
y8(0)
PLC-γ
0.1 μM
9(0)
PLC
b
l
0 0007
M
k22f = 4.8; k22b = 1.8
k23f = 0.8; k23b = 20
k24f = 4.8; k24b = 1.8
k25f = 10.3; k25b = 6
k26f = 0.01; k26b = 0
k27f = 0.3; k27b = 20
k28f = 0.2; k28b = 0
k29f = 100; k29b = 3
k30f = 100; k30b = 2
k31f = 100; k31b = 1
k32f = 100; k32b = 0.1
k33f = 0.99; k29b = 0.09
k34f = 2; k30b = 10
k35f = 8.8; k31b = 0.47
k36f = 1; k32b = 1
k37f = 1; k33b = 10
CaCyt = 0.1
Ca = 0.5
eCAMKIII = 0.06
S6K_thr = 0.001
S6K_Basal = 0.001 y(33) = CaM-Ca4 + CAMKIII →
CaMKIII_CaM-Ca4
% Binding of Calmodulin-Calcium
to CaMKIII
y(34) = CaMKIII_CaM-Ca4 + eEF2 →
eEF2thr-56 + CaMKIII_CaM-Ca4
% Phosphorylation of eEF2
y(35) = eEF2thr-56 + PP2A → eEF2 + PP2A
% Dephosphorylation of
eEF2thr-56
y(36) = CaMKIII + S6K_thr-252 → CaMKIII* +
S6K_thr-252
% Phosphorylation of CaMKIII
y(37) = CaMKIII + S6K_Basal → CaMKIII* +
S6K_thr-252
% Basal activation of CaMKIII
k22f = 4.8; k22b = 1.8
k23f = 0.8; k23b = 20
k24f = 4.8; k24b = 1.8
k25f = 10.3; k25b = 6
k26f = 0.01; k26b = 0
k27f = 0.3; k27b = 20
k28f = 0.2; k28b = 0
k29f = 100; k29b = 3
k30f = 100; k30b = 2
k31f = 100; k31b = 1
k32f = 100; k32b = 0.1
k33f = 0.99; k29b = 0.09
k34f = 2; k30b = 10 TABLE A3 | Chemical species and initial concentration for Module 2. APPENDIX y1(0)
BDNF
0.1 nM
y2(0)
TrKB
0.25 μM
y3(0)
Int_BDNF_TrKB2*_clx
0.25 μM
y6(0)
Shc
0.5 μM
y8(0)
PLC-γ
0.1 μM
y9(0)
PLC-γ_basal
0.0007 μM
y11(0)
Grb2
1 μM
y12(0)
Gab1
0.7 μM
y13(0)
PI3K
0.1 μM
y15(0)
PIP2
7 μM
y16(0)
PTEN
0.27 μM
y19(0)
PDK1
1 μM
y20(0)
AKT
0.2 μM
y22(0)
PP2A
0.15 μM
y23(0)
PIP3_PDK2
0.003 μM
y25(0)
TSC1–TSC2
1 μM
y27(0)
Rheb-GTP
1 μM
y29(0)
IP3
1 μM
y33(0)
CaMKIII
0.06 μM
y34(0)
eEF2
0.5 μM
y35(0)
PP2A
0.15 μM
y36(0)
S6K
0.17 μM TABLE A3 | Chemical species and initial concentration for Module 2. MODULE 1 | Pharmacotherapy (minocycline) activation through TNF-α in
NF-κB signaling pathway. MODULE 1 | Pharmacotherapy (minocycline) activation through TNF-α in
NF-κB signaling pathway. dx(1) = kprod-kdeg*x(1) − TN*r1*x(1)
% neutral IKK
dx(2) = TN*r1*x(1) − r3*x(2) − TN*r2*x(2)*x(8)
− kdeg*x(2) − a2*x(2)*x(10) + t1*x(4) −
a3*x(2)*x(13) + t2*x(5)
% free active IKK
dx(3) = r3*x(2) + TN*r2*x(2)*x(8) − kdeg*x(3)
% inactive IKK
dx(4) = a2*x(2)*x(10) − t1*x(4)
% cytoplasmic (IKK|IkBa)
complex
dx(5) = a3*x(2)*x(13) − t2*x(5)
% cytoplasmic (IKK|IkBa|NFkB)
complex
dx(6) = c6a*x(13) − a1*x(6)*x(10) + t2*x(5) −
i1*x(6)
% Free cytoplasmic NFkB
dx(7) = i1*kv*x(6) − a1*x(11)*x(7)
% Free nuclear NFkB
dx(8) = c4*x(9) − c5*x(8)
% Cytoplasmic PTGS2 gene
dx(9) = c2 + c1*x(7) − c3*x(9)
% PTGS2 transcription
dx(10) = -a2*x(2)*y(10) − a1*x(10)*x(6) +
c4a*x(12) − c5a*x(10) − i1a*x(10) + e1a*x(11)
% Free cytoplasmic IkBa
dx(11) = -a1*x(11)*x(7) + i1a*kv*x(10) −
e1a*kv*x(11)
% Free nuclear IkBan
dx(12) = c2a + c1a*x(7) − c3a*x(12)
% IkB transcription
dx(13) = a1*x(10)*x(6) − c6a*x(13) −
a3*x(2)*x(13) + e2a*x(14)
% Cytoplasmic(IkBa|NFkB)
complex
dx(14) = a1*x(11)*x(7) − e2a*kv*x(14)
% Nuclear (IkBa|NFkB) complex
dx(15) = c2c + c1c*x(7) − c3c*x(15)
% Control gene mRNA level TABLE A4 | The following association and dissociation rate constants
for Module 2 are taken from Ref. (29–33, 37, 39–80). APPENDIX Constant
Description
TN = 0/1 (OFF/ON state)
TNF-alpha inactive/active
c1c = 0.00005/100
Inducible transcription (control gene)
c2c = 0
Constitutive transcription (control gene)
c3c = 0.0004
mRNa degradation (control gene)
e1a = 0.0005
IkBa nuclear export Hoff, Fitted
i1a = 0.001
IkBa nuclear import Hoff, Fitted
e2a = 0.01
(IkBa|NFkB) nuclear export, Hoff blue (any short)
i1 = 0.0025
NFkB nuclear import, Hoff blue (short correspond
to a1)
c1a = AA*0.00005/100
Inducible (linear) IkBa mRNA synthesis, Fitted
c2a = AA*0.000000
Constitutive mRNA IkBasynthesis Fitted
c3a = 0.0004
mRNA IkBa degradation, Fitted
c4a = 0.005*100
IkBa translation rate, Fitted
c5a = 0.0001
IkBa degradation rate, Pando
c6a = 0.00002
(IkBa|NFkB) degradation, Hoff
AA = 1
AA = 1 wild-type cell, AA = 0 IkBa-deficient cell
t1 = 0.1
Degradation of (IKK|IkBa) (any short)
t2 = 0.1
Degradation of (IKK|IkBa|NFkB) (any short)
a1 = 0.5
IkBA*NFkB association Hoff (short, correspond
to i1)
a2 = 0.2
IKK*IkBa association, Fitted
a3 = 1
IKK*(IkBa|NFkb) association, Fitted
kdeg = 0.000125
Degradation of IKKa, IKKn, and IKKi
kprod = 0.000025
IKKn production rate
r3 = 0.0015
Spontaneous inactivation, Fitted
r2 = 0.1
Inactivation caused by PTGS2, Fitted
r1 = 0.0025
Activation caused by drug, Fitted
c5 = 0.0003
PTGS2 degradation rate, IkBa*5
c4 = 0.005*100
PTGS2 translation rate (Assumed)
c3 = 0.0004
PTGS2 mRNA degradation rate (Assumed)
c2 = AB*0.00000
constitutive PTGS2 mRNA synthesis (Assumed)
c1 = AB*0.00005/100
inducible PTGS2mRNA synthesis (Assumed)
AB = 1
AB = 1 wild-type cell, AB = 0 PTGS2-deficient
cell
kv = 5
ratio of cytoplasmic to nuclear volume
x13(0) = 0.06
Initial value of NF-κB is given in cytoplasmic
complex(IkBa|NFkB) TABLE A2 | The following association and dissociation rate constants for
module I are taken from Ref. (23, 26). Constant
Description %Fully AKT activation (Ser473) % Conversion of Rheb-GDP to
Rheb-GTP June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 14 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. APPENDIX BD = 0 (BDNF inactive)BD = 1 (BDNF active)
TR = 0 (TrkB inactive)
TR = 1 (TrkB active)
k1f = 1; k1b = 0.05
k2f = 1; k2b = 0.02
k3f = 0.02; k3b = 0
k4f = 0.01; k4b = 0
k5f = 0.001; k5b = 0.001
k6f = 0.8333; k6b = 0.3
k7f = 0.2; k7b = 0
k8f = 0.3; k8b = 0.5
k9f = 0.3; k9b = 0.5
k10f = 0.07; k10b = 0
k11f = 1; k11b = 1
k12f = 0.3; k12b = 1
k13f = 5; k13b = 0.08
k14f = 1.8; k14b = 5
k15f = 4; k15b = 4
k16f = 0.08; k16b = 5.5
k17f = 0.00068; k17b = 0.45
k18f = 4; k18b = 4
k19f = 0.7; k19b = 0.98
k20f = 45; k20b = 0.089
k21f = 0.4; k21b = 10 TABLE A4 | The following association and dissociation rate constants
for Module 2 are taken from Ref. (29–33, 37, 39–80). MODULE 2 | We now formulate the ordinary differential equations for the
above chemical reactions (Eqs 1–37). 1. dy(1) = k1f* dy(1)*BD + k1f* dy(2)*BD − k1b* dy(3)
2. dy(2) = k2f* dy(3) + k2f* dy(2)*TR − k2b* dy(3)
3. dy(3) = k3f* dy(3) − k3b* dy(4)
4. dy(4) = k4f* dy(4) − k4b* dy(5)
5. dy(5) = k5f* dy(5) − k5b* dy(2)
6. dy(6) = k6f* dy(6) + k6f* dy(4) − k6b* dy(4) + dy(7)
7. dy(7) = k7f* dy(7)-k7b* dy(6)
8. dy(8) = k8f* dy(8) + dy(4) − k8b* dy(4) -k8b* dy(10)
(Continued) MODULE 2 | We now formulate the ordinary differential equations for the
above chemical reactions (Eqs 1–37). June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org Frontiers in Neurology | www.frontiersin.org 15 In Silico Modeling of Multimodal Therapy for Stroke Alam et al. 9. dy(9) = k9f* dy(8) + k9f* dy(9)- k9b *dy(9) − k9b *dy(10)
10. dy(10) = k10f* dy(10) − k10b* dy(8)
11. dy(11) = k11f* dy(11) + k11f* dy(7) − k11b* dy(12)
12. dy(12) = k12f* dy(12) − k12b* dy(13)
13. dy(13) = k13f* dy(13) + k13f* dy(17) − k13b* dy(13)
14. dy(14) = k14f* dy(14) + k14f* dy(17) − k14b* dy(14)
15. dy(15) = k15f* dy(15) + k15f* dy(13) − k15b* dy(13) − k15b* dy(16)
16. dy(16) = k16f* dy(16) + k16f* PTEN − k16b* PTEN − k16b* dy(15)
17. Frontiers in Neurology | www.frontiersin.org June 2016 | Volume 7 | Article 94 APPENDIX dy(17) = k17f* d(17) − k17b* PI3K_basal
18. dy(18) = k18f* dy(15) + k18f* PI3K_basal − k18b* PI3K_basal
19. dy(19) = k19f* dy(16) + k19f* dy(19) − k19b* dy(19)
20. dy(20) = k20f * dy(16) + k20f* dy(20) − k20b* dy(21)
21. dy(21) = k21f* dy(20) + k21f* dy(19) − k21b* dy(19) − k21b* dy(22)
22. dy(22) = k22f* dy(22) + k22f* PP2A − k22b* PP2A -k22b* dy(21)
23. dy(23) = k23f* dy(22) + k23f* PIP3_PDK2 − k23b* PIP3_PDK2 − k23b*
dy(24)
24. dy(24) = k24f* dy(24) + PP2A − k24b* dy(22) − k24b* PP2A
25. dy(25) = k25f* dy(25) + k25f * dy(24) − k25b* dy(24) − k25b* dy(26)
26. dy(26) = k26f* dy(26) − k26b* dy(25)
27. dy(27) = k27f* dy(27) + k27f * dy(25) − k27b* dy(25) − k27b* dy(28)
28. dy(28) = k28f* dy(28) – k28b* dy(28)
29. dy(29) = k29f* dy(29) + k29f*IP3 − k29b* dy(30)
30. dy(30) = k30f* dy(30) + k30f*IP3 − k30b* dy(31)
31. dy(31) = k31f* dy(31) + k31f*IP3 − k31b* dy(32)
32. dy(32) = k32f* dy(32) + k32f*Ca − k32b* dy(32) − k32b*Cacyt
33. dy(33) = k33f* dy(33) + k33f* dy(36) − k37b* dy(34)
34. dy(34) = k34f* dy(34) + k34f* eEF2 − k34b* dy(335) − k334b* dy(34)
35. dy(35) = k35f* dy(35) + k35f* PP2A − k35b* eEF2 − k35b* PP2A
36. dy(36) = k36f* dy(36) + k36f* S6K_thr − k36b* dy(37) −
k36b* S6K_thr
37. dy(37) = k37f* dy(36) + k37f* S6K_Basal − k37b* dy(36) −
k37b* S6K_thr
MODULE 2 | Continued June 2016 | Volume 7 | Article 94 Frontiers in Neurology | www.frontiersin.org 16
|
https://openalex.org/W3209506333
|
https://jurnal.i3batu.ac.id/me/article/download/144/125
|
Indonesian
| null |
Manajemen Keuangan Dalam Perspektif Iman Kristen Bagi Lembaga-lembaga Kristen
|
Missio Ecclesiae /Missio Ecclesiae
| 2,021
|
cc-by
| 10,512
|
INFO ARTIKEL
ABSTRAK ___________________
Sejarah Artikel:
Diterima: Oktober 2021
Direvisi: Oktober 2021
Disetujui: Oktober
2021
Dipublikasi: Oktober
2021
___________________
Kata Kunci:
Manajemen Keuangan,
Perspektif, Iman
Kristen. _______________________
Keywords:
Financial Management,
Perspective, Christian
Faith. _______________________ ___________________
Sejarah Artikel:
Diterima: Oktober 2021
Direvisi: Oktober 2021
Disetujui: Oktober
2021
Dipublikasi: Oktober
2021
___________________
Kata Kunci:
Manajemen Keuangan,
Perspektif, Iman
Kristen. _______________________
Keywords:
Financial Management,
Perspective, Christian
Faith. _______________________ Sejarah Artikel:
Diterima: Oktober 2021
Direvisi: Oktober 2021
Disetujui: Oktober
2021
Dipublikasi: Oktober
2021 Lembaga Kristen termasuk lembaga yang jarang menerapkan manajemen
keuangan karena berbagai alasan: ketidakmengertian tentang manajemen, asumsi
yang keliru, kurangnya fleksibilitas dalam penerapannya dan menganggapnya
sebagai suatu ilmu pengetahuan sekuler yang tidak dapat diterapkan dalam suatu
lembaga Kristen atau bahkan menganggapnya bertentangan dengan iman Kristen. Tujuan penelitian ini adalah: 1) untuk memahami prinsip-prinsip Manajemen
Keuangan dalam perspektif iman Kristen; 2) untuk mengetahui sejauhmana
prinsip manajemen keuangan dalam perspektif iman Kristen diterapkan oleh
Lembaga Kristen. 3) untuk mengetahui kendala-kendala penerapan prinsip
manajemen keuangan dalam perspektif Iman Kristen sehingga dapat menolong
Lembaga Kristen memiliki Manajemen Keuangan yang bertanggung jawab. Metode Penelitian yang digunakan adalah metode penelitian kualitatif
menggunakan paradigma alamiah. Dalam pengumpulan data, penulis
menggunakan teknik pengumpulan data observasi, wawancara dan telaah
dokumen tertulis. Sebaliknya, analisis data menggunakan analisis domain,
analisis taksonomi, analisis komponen dan analisis tema. Hasil Penelitiannya
adalah bahwa: 1) Manajemen Keuangan dalam Perspektif Iman Kristen kurang
dipahami secara menyeluruh dan tidak secara khusus dapat mengaitkannya
dengan manajemen keuangan sehingga menemui kesulitan dalam hal praktis
implementasi dalam pelayanan; 2) Penerapan Prinsip Manajemen Keuangan
Dalam Perspektif Iman Kristen sebagian besar belum dilakukan dan belum
terorganisir dengan baik; 3) Lembaga-Lembaga Kristen secara umum menyadari
tanggung jawab keuangan yang dipercayakan namun menemui banyak kendala,
sebagai berikut: a) Sumber daya manusia tidak dilatih khusus untuk mengelola
dalam disiplin ilmu keuangan dan mengerjakannya dengan sikap yang benar;
b) Lembaga Kristen kurang fokus melakukan manajemen keuangan karena
kurangnya pemahaman mengenai manajemen keuangan dalam perspektif iman
Kristen. Kata Kunci:
Manajemen Keuangan,
Perspektif, Iman
Kristen. Keywords:
Financial Management,
Perspective, Christian
Faith. Missio Eclesiae
ISSN 2086-5368 (Print)
ISSN 2086-5368 (Online)
https://jurnal.i3batu.ac.id/index.php/me
Vol.10, No.2, pp. 169–189, 2021 Missio Eclesiae
ISSN 2086-5368 (Print)
ISSN 2086-5368 (Online)
https://jurnal.i3batu.ac.id/index.php/me
Vol.10, No.2, pp. 169–189, 2021 INSTITUT
INJIL
INDONESIA Manajemen Keuangan Dalam Perspektif Iman Kristen
Candrawatia,
aInstitut Injil Indonesia, candra.wagiyono@gmail.com aInstitut Injil Indonesia, candra.wagiyono@gmail.com ABSTRACT Financial management is rarely applied in Christian institutions for various
reasons: lack of understanding about it, wrong assumptions, lack of flexibility in
its application, consider it is a secular science and cannot be applied in a
Christian
institution
for
it’s
contrary
with
the
Christian
faith. The purposes of this research are:1) to understand the principles of Financial
Management from the Christian faith’s perspective; 2) to know how far Christian
institutions apply financial management principles in the Christian faith’s
perspective. 3) to know the obstacles of the application financial management
principles in the Christian Faith’s perspective. The method used is a qualitative
method using a natural paradigm. Data collection technique are observation, 169 Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) interviews and written document review. Data analysis uses domain analysis,
taxonomic analysis, component analysis and theme analysis. The results are: 1)
Financial Management of the Christian Faith’s perspective is not fully
understood and cannot specifically relate it to financial management so that it
has difficulties in practical implementation in services; 2) The application of the
financial management’s principles based on the Christian faith has not been
carried out and well organized; 3) In general, the Christian Institutes realize the
financial responsibilities trusted to them however they still find many obstacles,
as follows: a) Human resources are not specially trained to manage in the
discipline of finance and do that with the right attitude; b) The Christian
institutions are less focused on financial management due to a lack of
understanding about it from the Christian faith’s perspective. PENDAHULUAN Sekelompok orang yang saling mengikatkan dirinya guna mencapai suatu tujuan
tertentu dapat kita pikirkan sebagai suatu organisasi. Agar tujuan tersebut dapat dicapai
secara efektif dan efisien maka organisasi tersebut memerlukan manajemen (Siswanto, 1987,
p. 2). Manajemen diperlukan untuk mencapai tujuan, untuk menjaga keseimbangan tujuan-
tujuan tersebut supaya tidak yang saling bertentangan dan untuk mencapai efisiensi dan
efektivitas (Handoko, 2003, pp. 6–7). Manajemen terdapat dalam semua jenis organisasi. Ia bukan hanya pekerjaan dalam
perusahaan atau instansi pemerintah saja. Manajemen itu perlu untuk gereja, penjara, cafe,
restaurant, turnamen, ekspedisi pendaki gunung – dalam hampir segala macam situasi
organisasi (Kast, 1996, p. 2). Sebagai ilmu pengetahuan, manajemen juga bersifat universal,
dapat diterapkan dalam semua organisasi manusia, seperti perusahaan, pemerintah,
pendidikan, sosial, keagamaan dan lain-lainnya (Handoko, 2003, p. 6). Dalam pekerjaan rohani, Tuhan menghendaki dan memerintahkan manusia
mengerjakannya demi kepentingan manusia itu sendiri. Alkitab mencatat tentang Yusuf
yang mengelola kerajaannya dibawah persiapan Allah, sehingga dia menjadi tulang
punggung Israel (Kej. 41:49, dst) dan tentang Musa yang melaksanakan tugasnya dengan
suatu sistem manajemen berdasarkan nasehat Yitro mertuanya (Kel. 18:13-27) (Petrus
Octavianus, 2007, pp. 3–4). Dalam Ulangan 20 hal pengelolaan dipaparkan dengan jelas dan tegas. Tanah yang
didiami orang Israel adalah tanah yang diberikan Allah kepada mereka, bukan milik mereka
sendiri. Tanah itu kaya, berlimpah-limpah air susu dan madunya. Allah akan tetap
menjamin kesuburan tanah itu asalkan umat-Nya melaksanakan tanggung jawab mereka
mengelolanya (Dainton, 1990, p. 20). Lembaga Kristen adalah badan atau organisasi yang bergerak untuk mempengaruhi
kehidupan bermasyarakat dan bernegara. Keberhasilan Lembaga Kristen dalam mengelola
keuangan secara profesional dan spiritual akan menyebabkan keberhasilan sistem
manajemen dalam organisasi, yang pada akhirnya akan berdampak pada keberhasilan sistem
manajemen lembaga secara keseluruhan dan meningkatkan kredibilitas lembaga. Lembaga Kristen adalah lembaga yang jarang menerapkan manajemen karena
berbagai alasan: ketidakmengertian tentang manajemen, asumsi yang keliru, kurangnya
fleksibilitas dalam penerapannya dan menganggapnya sebagai suatu ilmu pengetahuan
sekuler dan tidak dapat diterapkan dalam suatu lembaga Kristen atau bahkan
menganggapnya bertentangan dengan iman Kristen. Olan Hendrix dalam pokok bahasan Why Has Management Been Neglected? mengungkapkan: “The first Reason is ignorance. We simply do not know how to manage. Another reason why we neglect this subject is that our traditional concept of leadership in
the church is the Strong Natural Leader.” (Olan Hendrix, 1988, pp. 21–22). PENDAHULUAN 170 Sementara itu, Robby I Gusti Candra mengungkapkan bahwa banyak orang di dalam
gereja merasa alergi pada manajemen karena asumsi-asumsi manajemen menjelaskan
tentang manajemen yang sarat dengan roh yang ingin mengendalikan banyak hal. Dijelaskan
bahwa ilmu manajemen merupakan suatu alat yang harus diteliti secara teologis dan filosofis
serta motivasi dan pola pikir manusia si pengguna alat tersebut. Manajemen dapat dijadikan
ekspresi sebagai motivasi untuk melakukan pekerjaan yang terbaik bagi Tuhan dan untuk
mewujudkan kesetiaan di dalam segala hal. Motivasi tersebut dapat berjalan dengan
manajemen sebagai alatnya (Candra, 1996, pp. 4–6). j
g
y
Yunus Cipta Wilangga mengemukakan juga bahwa dewasa ini ilmu-ilmu di luar
kekristenan yang biasa disebut ilmu sekuler sudah sangat maju. Meskipun ilmu-ilmu itu
disebut sekuler dalam artian tidak berada di bawah naungan Kekristenan, tidak berarti bahwa
ilmu-ilmu tersebut berkonotasi negatif. Sekuler tidak berarti mengajak orang bersikap
mengutamakan hal-hal duniawi. Ilmu-ilmu itu disebut sekuler barangkali karena belum
dirasakan manfaatnya oleh orang Kristen dalam kehidupan rohani mereka (Wilangga, 1996,
pp. 4–6). Hal tersebut didukung oleh tulisan David Secunda, mantan wakil presiden Asosiasi
Manajemen Amerika dan seorang pemikir Kristen, menulis tentang manajemen dalam
sebuah surat: Manajemen, menurut saya, tidak berisi hal-hal yang tidak cocok dengan prinsip
atau kepercayaan Kristen. Manajemen adalah alat untuk mencapai tujuan – bukan
tujuan itu sendiri – dan tidak mencari kesepakatan mengenai tujuan. Intinya
adalah usaha untuk meningkatkan potensi manusia dan tanpa hal ini, manajemen
menjadi sekotak alat dan teknik, yang berguna tetapi mempunyai kemungkinan
untuk disalahgunakan secara cerdik. Juga tidak ada alasan untuk membenarkan
organisasi Kristen yang jelek atau dikelola dengan buruk (Dayton., 1989, p. 29). Lembaga Kristen pada umumnya memiliki kekayaan untuk digunakan sebagai sarana
pencapaian tujuan dalam bidang-bidang sosial, kemanusiaan, dan keagamaan. Salah satu
tujuan yang bersifat kuantitatif mencakup manajemen organisasi yang tangguh (Bastian,
2002, p. 2). Oleh karena itu Manajemen menjadi bagian yang harus dilakukan oleh setiap
lembaga Kristen supaya memenuhi kewajiban organisasi. Di samping itu, pertanggungjawaban manajemen (managerial accountability)
merupakan bagian terpenting bagi kredibilitas manajemen di yayasan. Jika prinsip
pertanggungjawaban tersebut tidak terpenuhi dapat menimbulkan implikasi yang luas
(Bastian, 2002, p. 4). Salah satu unsur dari manajemen adalah uang, yaitu alat yang dibutuhkan untuk
mencapai tujuan yang diinginkan. Unsur manajemen ini berkembang menjadi bidang
manajemen keuangan yang mempelajari lebih mendalam peranannya dalam mencapai
tujuan yang diinginkan (Bastian, 2002, p. 3). Secara Umum, penilaian dan pengambilan keputusan adalah 2 (dua) hal pokok dalam
disiplin ilmu keuangan yang perlu diperhatikan (Atmaja, 1988, p. PENDAHULUAN 1). Oleh karena itu,
prinsip-prinsip keuangan kita perlu dipelajari untuk dapat memahami transaksi-transaksi
keuangan dan pembuatan keputusan keuangan yang terdiri atas kumpulan beberapa pendapat
fundamental yang membentuk dasar untuk teori keuangan dan pembuatan keputusan
keuangan (Atmaja, 1988, p. 5). Suatu masalah serius dalam kepemimpinan Kristen adalah mengelola keuangan
(Armerding, 1989, pp. 911–914). Petrus Octavianus mengemukakan tentang pentingnya
manajemen keuangan adalah sebagai berikut: 171 Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) Bagi lembaga Kristiani kepercayaan mengelola uang itu sangat penting. Karena
kehidupan lembaga gerejawi ialah bergantung kepada persembahan orang yang
berkorban karena percaya persembahan mereka dipakai sesuai dengan tujuan si
pemberi dalam garis kemuliaan dan pekerjaan Tuhan. Maka setiap pemimpin
hendaknya mengatur administrasi keuangan dengan disiplin. Paulus menulis:
“…kami sebagai hamba-hamba Kristus yang kepadanya dipercayakan rahasia…”
Pembuktian diri yang dapat dipercayai bukan hanya dalam pemberitaan Injil tetapi
termasuk rahasia mengelola uang merupakan manifestasi diakonia. Semakin jujur
mengelola uang, semakin nyata kuasa marturia (kesaksian) (Petrus Octavianus,
2007, p. 182). Bagi lembaga Kristiani kepercayaan mengelola uang itu sangat penting. Karena
kehidupan lembaga gerejawi ialah bergantung kepada persembahan orang yang
berkorban karena percaya persembahan mereka dipakai sesuai dengan tujuan si
pemberi dalam garis kemuliaan dan pekerjaan Tuhan. Maka setiap pemimpin
hendaknya mengatur administrasi keuangan dengan disiplin. Paulus menulis:
“…kami sebagai hamba-hamba Kristus yang kepadanya dipercayakan rahasia…”
Pembuktian diri yang dapat dipercayai bukan hanya dalam pemberitaan Injil tetapi
termasuk rahasia mengelola uang merupakan manifestasi diakonia. Semakin jujur
mengelola uang, semakin nyata kuasa marturia (kesaksian) (Petrus Octavianus,
2007, p. 182). Namun demikian hal tersebut tidaklah mudah karena ilmu pengetahuan umum
tentang manajemen keuangan telah mewarnai pengambilan keputusan-keputusan keuangan
yang belum tentu sesuai dengan prinsip-prinsip Alkitab. Pengelolaan yang sesuai dengan
Alkitab harus ditemukan untuk mengatasi masalah tersebut. Howard Dayton dalam
tulisannya mengungkapkan bahwa Alkitab melayani sebagai bimbingan dalam setiap aspek
kehidupan seseorang, termasuk hal-hal penting dalam keuangan (Dayton., 1989, p. 1). Menurut Larry Burkett, dalam Lukas 16:10-12 Yesus menyatakan bahwa pengaturan
uang yang baik merupakan suatu syarat utama untuk dipakai oleh Allah bagi hal-hal yang
lebih besar. Cara kita menggunakan uang merupakan pantulan yang mencerminkan apa yang
sesungguhnya kita percayai. Apakah kita tergolong orang Kristen yang sungguh-sungguh
percaya bahwa Allah memiliki segala sesuatu? Maka kita harus menyesuaikan hidup kita
dengan prinsip-prinsip-Nya. Kita harus bertanggung jawab atas penatalayanan kita dan atas
kesaksian yang positif maupun yang negatif, yang menyertainya (Burkett, 2006, p. 117). PENDAHULUAN Myron Rush menuliskan bahwa bila badan Kristen ingin berhasil dalam tugas-tugas
yang diberikan Allah kepada mereka, para pemimpinnya harus menerapkan prinsip-prinsip
manajemen yang digariskan dalam firman Allah, bukan yang dipromosikan dan dijalankan
oleh dunia sekular. Berarti kita harus berpaling pada firman Allah untuk mencari jawaban
tentang bagaimana pekerjaan-Nya harus dikelola (Rush, 2002, p. 13). Kitab Suci tidak mendukung praduga bahwa gereja harus berdiri jauh-jauh dari
bidang keuangan. Sesungguhnya, Kitab Suci mengajarkan bahwa hikmat datang dari Allah
(Ams. 3:13; 3:19; 8:10-11). Jadi, hikmat yang benar berkenaan dengan keuangan hanya
datang dari penyelidikan dan pengajaran firman Allah (Burkett, 2006, p. 116). Sugiyanto juga menjelaskan bahwa firman Tuhan sebagaimana tertulis memberikan
hikmat, menuntun orang kepada keselamatan, berguna untuk mengajar, menyatakan
kesalahan, memperbaiki perilaku dan untuk mendidik orang dalam kebenaran firman Tuhan
(2 Tim. 3:15-16). Selain itu firman Tuhan merupakan pedoman dalam segala usaha dan
kegiatan serta peri kehidupannya (Mzm. 119:105, 130), yang tentu saja termasuk di
dalamnya adalah usaha dan kegiatannya dalam bidang manajemen keuangan (Sugiyanto
Wiryoputro, 2004, p. 3). Oleh karena itu, penulis mencoba untuk mengkaji lebih dalam mengenai manajemen
keuangan yang bersumber pada Alkitab sebagai firman Tuhan untuk menyajikan informasi
dasar yang jelas bagi pembaca secara khusus bagi Lembaga Kristen. Tantangan teknologi yang pesat, berupa perubahan sistem keuangan berbasis
komputer, perubahan sistem keuangan dari desentralisasi menjadi sentralisasi membuat
sistem informasi keuangan menjadi terintegrasi dan perubahan peran sumber daya manusia
karena alih generasi membuat setiap pelaksana kegiatan suatu lembaga harus menyesuaikan
gerak langkahnya agar terpadu satu sama lain mencapai tujuan. Dalam Alkitab, pengelolaan menunjuk kepada tanggung jawab seseorang yang
dipercayai mengurus dan mengelola kekayaan seseorang (Dainton, 1990, p. 67). 172 Penanggung Jawab Keuangan menjadi bagian yang tidak terpisahkan dari suatu lembaga
yang memikul tanggung jawab pengelolaan dan pengambilan keputusan sesuai dengan
kewenangannya dalam aspek profesional dan spiritual. Penanggung Jawab Keuangan menjadi bagian yang tidak terpisahkan dari suatu lembaga
yang memikul tanggung jawab pengelolaan dan pengambilan keputusan sesuai dengan
kewenangannya dalam aspek profesional dan spiritual. Aspek profesional. Menurut Irin Widayati kecerdasan finansial adalah salah satu
kecerdasan yang harus dimiliki oleh manusia masa kini, yaitu kecerdasan dalam mengelola
keuangan dengan benar, maka seseorang bisa diharapkan bisa mendapatkan manfaat yang
maksimal (Widayati, 2012, p. 1). Aspek Spiritual. Di dalam buku Pegangan Pelayanan Billy Graham dijelaskan bahwa
pengertian dan kemampuan menangani keuangan secara tepat harus menjadi prioritas utama
setiap orang. Sedikit sekali gereja yang membina warganya soal pertanggungan jawab
keuangan. PENDAHULUAN Hakekat masalah ini bersifat rohani (Ward, 1993, pp. 130–131). Maka dari itu
setiap orang harus kembali kepada Alkitab untuk memahami pengelolaan yang benar dan
memecahkan masalah-masalah keuangan yang terjadi. Petrus Octavianus menjelaskan bahwa masalah keuangan merupakan masalah yang
pelik dan halus. Perkara ini sering diabaikan dan dibicarakan dalam kehidupan
kepemimpinan Kristen. Tetapi justru kegagalan hamba Tuhan seringkali terletak pada
ketidakmampuannya mengurus keuangannya. Karena itu perlu membahas keuangan hamba
Tuhan (Petrus Octavianus, 2007, p. 186). Yesus mendorong para rasul-Nya agar menganggap diri sebagai pengelola. Dan
Yesus memakai gagasan itu dalam banyak perumpamaan. Mereka diberi kuasa atas semua
apa yang mereka punyai, dan harus siap memberikan pertanggung jawaban kepada Allah
tentang cara mereka menggunakan waktu, harta, kuasa dan kesempatan (Mat. 25:14-30). Mempertajam gagasan itu, Paulus menganggap diri sendiri sebagai hamba Allah
bukan saja dalam arti umum, melainkan juga sebagai pengelola atas anugerah Allah. Yang
Paulus maksudkan adalah seluruh pekerjaannya sebagai seorang rasul dalam mengabarkan
Injil dan mendirikan gereja. Dengan kata lain, Paulus merasa bahwa ia berhutang kepada
semua orang, non Yahudi atau Yahudi dan bertanggung jawab untuk membayarnya dengan
pekerjaan penginjilannya. Petrus menulis dalam suratnya yang pertama bahwa semua orang
Kristen harus menganggap diri sebagai pengelola anugerah Allah. Karena anugerah Allah
itu beranekaragam, kaya dan multi kompleks, maka seluruh umat Kristen harus bekerja sama
untuk mengetahui dan mempraktekkannya (Dainton, 1990, pp. 68–69). Menurut pengamatan penulis, di dalam aktivitas keuangan Lembaga Kristen
seringkali terjadi ketidakpahaman, kesalahpahaman dan perbedaan penafsiran mengenai
prinsip-prinsip keuangan baik secara profesional maupun yang alkitabiah sehingga
menyebabkan konflik yang tidak perlu di antara para pelaku keuangan. Di samping itu belum adanya literatur yang komprehensif dengan ciri khas budaya
organisasi Lembaga Kristen tentang prinsip-prinsip keuangan yang Alkitabiah membuat
kurang terpadunya gerak langkah suatu lembaga dalam mencapai tujuan. Oleh karena itu penulis berpendapat bahwa memahami manajemen keuangan yang
Alkitabiah dan menerapkannya menjadi suatu pilihan yang tidak dapat dielakkan bagi
penanggung jawab keuangan Lembaga Kristen sehingga penulis terbeban untuk
mengupayakan adanya literatur mengenai prinsip-prinsip manajemen keuangan yang
alkitabiah supaya meminimalkan konflik dan seluruh jajaran dapat bergerak terpadu
mencapai tujuan, yaitu melaksanakan Amanat Agung Tuhan Yesus. KAJIAN LITERATUR Manajemen Keuangan Dalam Perspektif Iman Kristen Kata “perspektif” dalam Kamus Besar Bahasa Indonesia berarti sudut pandang atau
pandangan (Redaksi, 2001, p. 854). Iman adalah kepercayaan (yang berkenaan dengan 173 Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) agama), keyakinan dan kepercayaan kepada Allah, nabi, kitab dan sebagainya. Sedangkan
kata Kristen adalah agama yang disampaikan oleh Kristus (Redaksi, 2001, p. 372). Jadi
secara harafiah kata “perspektif Iman Kristen” berarti sudut pandang atau pandangan dalam
agama Kristen yang diyakini. Dengan demikian, pengertian Manajemen Keuangan dalam Perspektif Kristen adalah
Manajemen Keuangan dalam sudut pandang agama Kristen yang berlandaskan Alkitab
sebagai firman Tuhan. Tujuan Manajemen Keuangan Dalam Perspektif Iman Kristen Setiap manusia membutuhkan sesuatu termasuk uang dan harta benda untuk
memenuhi kebutuhan hidupnya. Apapun yang dibutuhkan manusia untuk memenuhi
kebutuhan harus diperlakukan sebagai alat dan bukan tujuan. Kalau harta benda dan uang
sudah menjadi tujuan, maka orang mulai terjerumus kepada materialisme. Tuhan Yesus
mengingatkan bahwa ada hal yang lebih penting dari materi, dengan mengatakan, "Apa
gunanya seseorang memperoleh seluruh dunia tetapi kehilangan nyawa?" (Mat. 16:26), dan
lagi "... hidup itu lebih penting dari makan dan tubuh itu lebih penting dari pakaian?" (Mat. 6:26) (Nainggolan, 2012, p. 29). Dengan demikian, harta benda dan uang dibutuhkan untuk hidup, bukannya hidup
untuk harta benda dan uang. Harta benda dan uang janganlah menjadi tujuan hidup agar
hidup tidak diabdikan untuk harta benda dan uang (band. Mat. 6:19-21). (Nainggolan, 2012,
p. 29) Tujuan dari setiap orang Kristen manapun, dalam bisnis atau dalam bidang-bidang
lainnya adalah untuk memuliakan Allah, tidak hanya untuk mendapatkan keuntungan. (Burkett, 2006, p. 183). Jangan mencintai harta benda ataupun uang walaupun
membutuhkannya (Mat. 6:21; 2 Tim. 3:2; 1 Tim. 6:10). Karena bila harta benda dan uang
menjadi tujuan hidup, uang akan dikejar dan orang Kristen dapat menyimpang dari iman. (Tomatala, 1993, p. 30) Pengkhotbah dengan jelas menyatakan: "Siapa mencintai uang
tidak akan puas dengan uang, dan siapa mencintai kekayaan tidak akan puas dengan
penghasilannya. Ini pun sia-sia (Pkh. 5:9). Salah satu tujuan dari pengelolaan keuangan dalam dunia bisnis adalah
mengumpulkan kekayaan. Orang Kristen secara etis diperhadapkan pada dua pilihan, yaitu
mengabdi pada harta duniawi atau pada harta sorgawi. Orang percaya tidak boleh lagi fokus
kepada mengumpulkan harta duniawi demi kepuasan diri melainkan mengumpulkan harta
surgawi. (Sosipater, 2010, p. 2013) Mengumpulkan harta di dunia mengandung unsur keserakahan dan ketamakan
manusia yang suka menimbun harta melebihi kebutuhan hidupnya. Hal ini merupakan sikap
moral yang tidak benar. Orang percaya harus mengumpulkan uangnya untuk kepentingan
hidup kekal. Mengumpulkan harta di surga bukanlah mengumpulkan harta seperti di dunia
ini, tetapi melakukan segala sesuatu, termasuk mengumpulkan uang yang berkaitan dengan
hidup kekal dan kerajaan Allah. Jadi, hal yang terutama adalah meraih keselamatan kekal
dan mengabdi demi kerajaan Allah, maka berkat Tuhan akan mengalir deras, termasuk
dalam kehidupan keluarga dan bisnisnya. Oleh karena itu, tujuan utama Manajemen Keuangan dalam perspektif iman Kristen
bukanlah untuk mengumpulkan harta sebanyak mungkin melainkan fokus kepada
pengelolaan untuk keselamatan kekal sehingga nama Tuhan dipermuliakan melalui
pengelolaan yang baik. Fungsi dan Aktivitas Manajemen Keuangan Dalam Perspektif Kristen Fungsi dan Aktivitas Manajemen Keuangan Dalam Perspektif Kristen Fungsi dan Aktivitas Manajemen Keuangan telah banyak dijumpai di dalam Alkitab
tanpa disadari. Bagian ini memaparkan hal-hal yang berkaitan dengan fungsi dan aktivitas
manajemen keuangan. 174 Adam Adam adalah manusia pertama yang diciptakan oleh Allah menurut gambar dan rupa
Allah (Kej. 1:26). Selain itu dia diberi kuasa atas segala binatang dan menempatkannya di
taman Eden untuk mengusahakan taman itu dan memeliharanya (Kej. 2:8-14). Lalu Allah memandang bahwa: "Tidak baik, kalau manusia itu seorang diri saja..."
(Kej. 2:18). Maka hadirlah Hawa sebagai manusia kedua yang diciptakan Allah untuk
menolong Hawa. g
Namun atas tipu daya ular, Hawa membujuk Adam untuk memakan buah yang
dilarang oleh Allah untuk dimakan, yaitu buah pengetahuan tentang yang baik dan yang
jahat. Maka jatuhlah mereka ke dalam dosa yang dalam. Lalu di usirlah mereka dari Taman
Eden. Adam harus mengelola tanah untuk mendapatkan makanannya: "Lalu TUHAN Allah
mengusir dia dari taman Eden supaya ia mengusahakan tanah dari mana ia diambil" (Kej. 3:23). )
Larry Burkett menyebutnya sebagai investor pertama karena Adam harus mengambil
resiko dengan menanam apa yang seharusnya dapat dimakan. (Walborn & Chan, 2001, p. 131). "Mengusahakan" dalam Perjanjian Lama digunakan kata dbel (labad) dari akar kata
dbe (abad) (Kejadian 3:23 (Versi Paralel) - Tampilan Ayat - Alkitab SABDA, n.d.), dalam
bahasa Inggris adalah to serve, cultivate, enslave, work, yang berarti melayani; mengolah,
memperbudak, bekerja (Strong, 2001, p. 201). Maka dari itu Adam harus berjuang untuk
mengelola tanah supaya ia mendapatkan makanannya. Kesusahan dan penderitaan menjadi
bagian yang tidak terpisahkan ketika bekerja mengelola tanah sebagaimana kutuk yang telah
difirmankan Tuhan akibat dosa Adam: "…dengan bersusah payah engkau akan mencari
rezekimu dari tanah seumur hidupmu." (Kej. 3:17). Lambat laun manusia harus meningkatkan hasil tanahnya dan mengembangkannya
karena jumlahnya yang bertambah banyak. Dan bahkan mengusahakan lebih banyak hasil
demi kemakmuran yang ingin dinikmati dan bagi generasi anak cucu berikutnya. Demikianlah investasi dan investor akan terus bertambah dari masa ke masa seiring dengan
pertambahan manusia. Dari uraian di atas kita dapat mengetahui prinsip-prinsip setelah kejatuhan manusia
dalam dosa terkait dengan manajemen keuangan bahwa asset harus dikelola dengan kerja
keras dan perjuangan supaya dapat menghasilkan dan memberi kehidupan di dunia ini. Yusuf Yusuf adalah anak Yakub yang ke-11, dari istrinya Rahel (Kej. 30:24; 35:24), dan
anak yg paling dikasihi Yakub (Kej. 37:3; band 33:2, 7). Yusuf adalah anak yg dimanjakan,
dijual menjadi budak orang Mesir karena kecemburuan kakak-kakaknya; dia dihukum
sebagai korban fitnah, lalu naik menduduki jabatan tertinggi pemerintahan. Dengan rencana
yg bijaksana ia dapat mengatasi bencana kelaparan, sehingga menyelamatkan negeri Mesir,
Kanaan dan keluarganya dari bahaya mati kelaparan (Joseph - Studi Kamus - Alkitab
SABDA, n.d.) Oleh karena itu perlu dicermati bagaimana Yusuf dapat menghadapi masa-
masa bencana kelaparan itu. Rencana bijaksana Yusuf dimulai dari mimpi Firaun yang diartikan oleh Yusuf. Yusuf memberitahukan pesan yang diterimanya dari Allah mengenai arti mimpi tersebut
bahwa akan segera datang masa tujuh tahun kelimpahan di seluruh tanah Mesir dan
kemudian akan timbul masa tujuh tahun kelaparan, bahkan akan terjadi sangat hebatnya
kelaparan tersebut (Kej. 41:25-32). Selain menyampaikan makna mimpi Firaun, Yusuf dengan penuh keberanian juga
menyampaikan usul kepada Firaun mengenai apa yang harus diperbuat oleh Firaun (Kej. 41:33-37). Disini nampak adanya perencanaan yang baik, yang datangnya dari Allah untuk 175 Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) mengatasi bala kelaparan yang akan datang. Perencanaan Yusuf meliputi: 1) menempatkan
seorang manajer yang tepat, yaitu seorang yang berakal budi dan bijaksana; 2) menempatkan
penilik-penilik, yaitu dyqp yang berarti "one who looks after" in the sense of to number,
muster, draw up (troops) - "orang yang menjaga" dalam arti jumlah, mengumpulkan,
menyusun (pasukan) (Strong, 2001, p. 230); 3) menentukan jumlah gandum yang disimpan
untuk masa kelaparan yang akan terjadi di tanah Mesir; 4) menentukan waktu untuk
menyimpan gandum tersebut. Firaun bukan hanya menerima usul dari Yusuf tetapi juga mengakui bahwa Yusuf
adalah seorang yang penuh dengan Roh Allah dan bahwa semua hal yang disampaikan oleh
Yusuf adalah berasal dari Allah. Firaun memandang Yusuf sebagai orang yang berakal budi
dan bijaksana serta tidak ada orang yang seperti dia sehingga dia dijadikan penguasa atas
tanah Mesir (Kej. 41:37-46). Sebagaimana ditulis dalam Yakobus 2:26: "Sebab seperti tubuh tanpa roh adalah
mati, demikian jugalah iman tanpa perbuatan-perbuatan adalah mati." Yusuf tepat
melakukan tepat seperti apa yang dikatakannya kepada Firaun (Kej. 41:48-49). Iman Yusuf nyata saat segala hal belum terjadi. Masa kelaparan belum terjadi tetapi
apa yang dinyatakan Allah kepada-Nya tidak diabaikan. Atas hikmat Allah, Yusuf
menyimpan bahan makanan pada masa kelimpahan untuk masa kelaparan supaya negeri
Mesir jangan binasa karena kelaparan tersebut. Penataan Tuhan Mengenai Persembahan (Bilangan 18) Yusuf Nampak tujuan Ilahi yang diselesaikan oleh
Yusuf di dalam tindakannya. Pengaturan jangka pendek dan jangka panjang juga dilakukan tepat seperti apa yang
direncanakannya. Sumber daya manusia menjadi andalannya dalam pengaturan tersebut
sehingga semua dapat berjalan dengan baik. Gandum dikumpulkan dengan pengaturan yang baik di setiap kota. Masing-masing
kota akan memenuhi kebutuhannya sendiri sehingga terjadi keteraturan distribusi pangan
pada saatnya. Tidak lupa dilakukan penghitungan gandum yang disimpan untuk
memastikan tercukupinya kebutuhan setiap orang walaupun pada akhirnya penghitungan
tersebut dihentikan karena melimpahnya gandum sehingga tidak dapat dihitung lagi. Allah
melimpahkan berkatnya disaat Yusuf memenuhi apa yang dikehendaki-Nya untuk
dilakukan, yaitu memelihara suatu bangsa yang besar (Kej. 50:20). y
g
y
g
j
Dari uraian di atas maka prinsip manajemen keuangan dalam manajemen persediaan
Yusuf adalah: 1) hikmat Allah adalah hal utama dalam Yusuf melakukan manajemen;
2) Yusuf melakukan fungsi manajemen dengan baik, nampak dari adanya perencanaan
dalam setiap tindakan, yang meliputi perencanaan sumber daya, perencanaan strategis,
perencanaan waktu, perencanaan kerja dan perencanaan kegiatan yang didasarkan pada
hikmat yang Allah berikan; adanya pengorganisasian sumber daya yang ada, seperti sumber
daya manusia dan sumber daya pangan pada setiap wilayah kota; adanya pengawasan dan
pengendalian dalam mengimplementasikan rencananya supaya dapat berjalan dengan baik;
adanya pendelegasian rencana kerja kepada setiap penanggungjawab di kota-kota; 3)
Yusuf melakukan prinsip-prinsip manajemen keuangan dengan baik, seperti adanya
konsistensi penyimpanan gandum selama tujuh tahun masa kelimpahan, akuntabilitas
sampai orang berhenti menghitungnya karena terlalu banyak jumlahnya dan integritas
sumber daya manusia sehingga tidak ada kecurangan dalam pengumpulan gandum; 4)
Manajemen persediaan berbicara mengenai pengaturan persediaan jangka pendek dan
jangka panjang yang dilakukan untuk memenuhi tujuan Allah yang telah dinyatakan; 5)
Allah melimpahkan berkat kepada Yusuf ketika manajemen keuangan dilakukan dalam
kehendak-Nya. Penataan Tuhan Mengenai Persembahan (Bilangan 18) Penataan Tuhan Mengenai Persembahan (Bilangan 18) 176 Tuhan secara khusus berfirman kepada Harun mengenai bagaimana mengelola
persembahan yang masuk ke dalam rumah Tuhan (Bil. 18:8). Pada bagian ini nampak bahwa
Tuhan sangat peduli dengan pengaturan keuangan, secara khusus persembahan yang
diserahkan pemeliharaannya kepada Harun. Tuhan juga secara rinci dan jelas memberikan
ketetapan-ketetapan bagian mana saja yang menjadi bagian Harun (Bil. 18:9-19). Mengenai asset bagi Harun dan bagian dari bani Lewi juga diatur oleh Tuhan dalam Bil. 18:20-32. Yusuf Dengan demikian dapat diketahui bahwa: 1) Tuhan peduli dengan manajemen
keuangan, secara khusus persembahan yang masuk dalam rumah-Nya sehingga manajemen
keuangan harus diterapkan dalam perbendaharaan rumah Tuhan karena Tuhan sendiri
melakukannya; 2) Ketetapan atau peraturan-peraturan dalam manajemen keuangan harus
diatur dengan jelas dan rinci sebagaimana yang Tuhan lakukan serta harus dikomunikasikan
juga dengan jelas dan tegas sehingga tidak ada kesimpangsiuran dalam pelaksanaannya; 3)
Tuhan mengatur tanggung jawab hamba-Nya dan apa yang menjadi bagian bagi hamba-
hambaNya. Dengan demikian manajemen keuangan harus diterapkan karena Tuhan sendiri
telah melakukannya. Daud Daud merupakan raja Israel yang sangat mengasihi Tuhan sehingga berhasrat untuk
membangun Bait Suci. Namun Tuhan menetapkan Salomo untuk membangun Bait Suci. (1
Taw. 22:8). Oleh karena itu ketika Daud telah menjadi tua dan lanjut umur, ia mengadakan
persiapan untuk mendirikan Bait Suci tersebut. Dalam persiapan mendirikan Bait Suci inilah
nampak manajemen keuangan yang Daud lakukan walaupun pada pelaksanaannya bukan
dia yang melakukannya. Daud mengangkat Salomo menjadi raja menggantikan dirinya atas Israel dan
mengumpulkan segala pembesar Israel, juga para Imam dan orang-orang Lewi, lalu
mengatur seluruh tugas dan tanggung jawab mereka. Masing-masing diatur dengan jelas
jabatan dan deskripsi pekerjaannya (1 Taw. 23:1 - 27:34). Daud melakukan
pengorganisasian. Sebagai bagian dari fungsi manajemen keuangan, Daud merencanakan
setiap detail dari pembangunan Bait Suci tersebut (1 Taw. 28:11-12). Ia menyiapkan seratus ribu talenta emas dan sejuta talenta perak dan sangat banyak
tembaga dan besi sehingga beratnya tidak tertmbang serta sejumlah kayu dan batu dan
sebagainya. Bahkan karena cintanya kepada Tuhan, Daud memberikan emas dan perak
kepunyaannya sendiri menjadi bagian persediaan bagi rumah kudus (1 Taw. 28:14-18; 29:2-
9). Di atas semuanya itu, Daud menyatakan bahwa perencanaan mengenai Bait Suci itu
diilhamkan Tuhan kepadanya, yaitu petunjuk tentang segala pelaksanaan rencana itu (1
Taw. 28:19) Tugas pengawas perbendaharaan rumah Allah adalah tugas orang-orang Lewi yang
ditetapkan oleh Daud. Di samping itu Daud membagi pengawasan atas perbendaharaan
rumah Allah dan atas perbendaharaan barang-barang kudus. Dia juga menunjuk Sebuel bin
Gersom bin Musa menjadi kepala perbendaharaan. Ini menunjukkan penting dan perlunya
tugas pengawasan perbendaharaan disamping tugas dan tanggung jawab yang lain yang
ditetapkan oleh Daud (1 Taw. 26:26-28). Alkitab mencatat fungsi Pengawasan yang dilakukan oleh Daud dalam 1 Tawarikh
26:28. Pengkhotbah 5:7 juga menyatakan, “Pejabat tinggi yang satu mengawasi yang lain,
begitu pula pejabat-pejabat yang lebih tinggi mengawasi mereka”. Menurut Alkitab,
Tuhanlah yang mengawasi atau mengendalikan manusia: 1) Tuhan yang mengamat-amati
dan menghitung setiap langkah dan jalan manusia (Ayb. 31:4); 2). Setiap langkah manusia
diawasi oleh Tuhan (Ams. 5:21); 3) Tuhan mengawasi orang yang jahat dan orang yang baik 177 Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) (Ams. 15:3); 4) Tuhan mengawasi bangsa-bangsa (Mzm. 66:7); 5) Tuhan selalu mengawasi
dari awal sampai akhir tahun (Ul. 11:12). (Sugiyanto Wiryoputro, 2004, p. 87) Prosedur lancar, metode baik, kebijaksanaan tepat, tetapi tanpa disiplin kerja, gerak
maju suatu organisasi akan tersendat-sendat. Sebab manusia cenderung untuk mencari yang
enak, mencari yang lebih santai, menjadi malas. Semua itu bisa terjadi. Daud Oleh karena itu,
target dan disiplin harus dibuat dan diawasi. Pengawasan itu tidak hanya datang dari sang
pemimpin, tetapi juga datang dari orang yang dipimpin. Apalagi dalam hal keuangan. Hal
percaya memang sangat diperlukan, tetapi percaya saja tanpa pengawasan dan disiplin, maka
kepercayaan itu akan bisa menjadi sesuatu yang menyusahkan. Sangat penting memimpin
dan mengawasi namun bukan memata-matai. Ini berarti, bahwa pemimpin juga dapat
mengambil tindakan yang berhubungan dengan disiplin. (Petrus Octavianus, 1988, p. 87) Oleh karena itu prinsip manajemen keuangan yang dilakukan dalam bagian ini
adalah: 1) Daud melakukan perencanaan secara detail dan rapi sebagai bagian dari
kecintaannya akan rumah Tuhan; 2) Daud melakukan pengorganisasian yang jelas terhadap
sumber daya manusia beserta dengan tugas dan tanggung jawabnya masing-masing;
3) Daud membentuk dewan pengawas atas perbendaharaan dan harta benda. Salomo
S Salomo mengadakan program pembangunan yang luas. Pekerjaan ini membutuhkan
tenaga kerja dengan organisasi yang kompleks, pengumpulan bahan bangunan yang diimpor
dan penghimpunan kekayaan (Packer, J.I., Merrill C. Tenney & William White, 2003, pp. 676–677). Pada awal pemerintahannya, Salomo mengasihi Tuhan dan hidup menurut ketetapan-
ketetapan-Nya (1 Raj. 3:3). Sebagai Raja, dia memohon hikmat dalam pemerintahannya
(1 Raj. 3:7-10). Sebagai jawaban atas permohonannya, Allah memberikan hikmat dan
pengertian yang amat besar kepadanya (1 Raj. 4:29-30). Dengan kebijaksanaan ini, Salomo
mengatur rakyatnya, mengadakan perjanjian internasional untuk memperoleh bahan,
menghimpun kekayaan dan menjalankan program pembangunannya. Ia memberikan
perhatian saksama kepada pembangunan dan pentahbisan bait suci karena proyek itulah
merupakan peristiwa utama dari kehidupannya. (Packer, J.I., Merrill C. Tenney & William
White, 2003, pp. 676–677). Ia memiliki delapan pembesar, salah satunya adalah Yosafat bin Ahilud sebagai
bendahara negara dan dua belas orang kepala daerah yang bekerja atas seluruh Israel
(1 Raj. 4:1-20). Salomo mulai dengan mengadakan persetujuan perdagangan bersama dengan Hiram
(Huram), raja Tirus, untuk membeli kayu aras, kayu sanobar dan kayu cendana. Ia
membayarnya dengan gandum, jelai, minyak dan anggur (1 Raj. 5:2-12; 2 Taw. 2:3-10). Salomo mengerahkan 30.000 penebang kayu dari Israel dan mengirim 10.000 orang dari
mereka ke Libanon. Mereka bekerja menurut jadwal yang tetap: sebulan di Libanon dan dua
bulan di rumah (Packer, J.I., Merrill C. Tenney & William White, 2003, pp. 676–677). Karena memerlukan lebih banyak tenaga kerja, Salomo memperbudak orang Kanaan
yang tinggal di Israel. Tujuh puluh ribu orang di antara mereka bekerja dalam pengangkutan,
80.000 menjadi pemahat batu dan 3.600 menjadi pengawas (Packer, J.I., Merrill C. Tenney
& William White, 2003, pp. 676–677). Pada waktu kerajaan Salomo menjadi makin luas, ia menuntut upeti dari raja-raja di
daerah-daerah yang ditaklukkannya (2 Taw. 9:13). Salomo juga mengumpulkan uang dari
para saudagar yang menggunakan jalur-jalur perdagangan di Israel (9:14) (Packer, J.I.,
Merrill C. Tenney & William White, 2003, pp. 676–677). Para saudagar Salomo membawa kereta perang dari Mesir dan menjualnya kepada
raja orang Het dan raja orang Aram (1 Raj. 10:28-29). Mereka membangun armada kapal 178 dan memeperawaknya dengan para pelaut Israel dan para pelaut Hiram, dan mengirim
armada itu ke Ofir. Para pelaut ini kembali dengan 420 talenta emas. Dari sumber lain di
luar Alkitab kita mengetahui bahwa Salomo menjalankan sebuah usaha pertambangan dan
peleburan yang besar di Gurun Sinai. Sebagai akibatnya, perak menjadi umum sekali di
Yerusalem (1 Raj. 10:27; 2 Taw. 9:20, 27). Salomo
S Pada akhir hidupnya, Salomo telah berpaling dari Tuhan. Cara hidupnya yang serba
mewah segera mendatangkan bencana ke atas kerajaan itu (Packer, J.I., Merrill C. Tenney
& William White, 2003, pp. 676–677). Ia mencintai banyak perempuan asing yang
kemudian mencondongkannya kepada allah-allah mereka. Ia mengikuti Asytoret, dewi
orang Sidon dan mengikuti Milkom, dewa kejijikan sembahan orang Amon dan mendirikan
bukit pengorbanan bagi Kamos, dewa kejijikan sembahan orang Moab dan bagi Molokh,
dewa kejijikan sembahan orang bani Amon. Salomo melakukan apa yang jahat di mata
Tuhan (1 Raj. 11:1-13) Sepuluh suku bangsa memisahkan diri dari Rehabeam untuk membentuk kerajaan
Israel di bawah pimpinan Yerobeam (1 Raj. 12:16-24) sebagaimana yang difirmankan Tuhan
kepadanya (1 Raj. 11:11). Jadi dalam manajemen keuangan bukanlah uang yang menjadi hal utama melainkan
hidup bergantung kepada Tuhan sehingga mendapatkan hikmat untuk mendapatkan uang
atau kekayaan yang dibutuhkan sekaligus mendapatkan hikmat untuk mengatur dan
mengelolanya dengan tepat sesuai dengan kehendak Allah. Ketika Allah menjadi yang
utama maka berkat akan melimpah melalui hikmat-Nya, sebaliknya ketika Allah tidak
berada di tempat yang utama maka bencana akan terjadi. Oleh karena itu prinsip-prinsip manajemen keuangan yang dilakukan oleh Salomo
adalah: 1) hikmat Allah dalam melakukan manajemen keuangan; 2) ada tujuan Ilahi yang
ditetapkan, yaitu membangun Bait Suci; 3) fungsi manajemen keuangan, seperti
perencanaan,
pengorganisasian,
pengendalian
dan
pengawasan
nampak
dalam
pemerintahannya secara khusus dalam mendirikan Bait Suci. Yesus dan ajaran-Nya Dalam bagian ini adalah pengajaran Yesus mengenai manajemen keuangan yang
perlu dijadikan landasan dalam mengelola keuangan. b) Investasi Perumpamaan tentang talenta ini menunjukkan perlunya berinvestasi dalam rangka
menggunakan pemberian Allah dengan bertanggung-jawab. Investasi adalah bagian dari
manajemen yang harus dikerjakan dengan sikap yang baik dan setia tanpa kehadiran atau
pengawasan majikan mereka. Apabila investasi dilarang atau bahkan tidak didorong,
mengapa Tuhan Yesus menggunakannya sebagai contoh dan memberikan pahala kepada
yang paling rajin ? Jawabannya jelas bahwa investasi adalah satu bagian lain dari manajemen
keuangan. (Burkett, 2006, p. 132) Menurut Larry Burkett, Investasi yang benar menurut Alkitab ialah melipatgandakan
harta yang ada untuk memenuhi kebutuhan masa depan. (Burkett, 2006, p. 47) Ada dua
alasan yang benar untuk berinvestasi: 1) untuk memperluas kerajaan Allah. 2) tanggung
jawab keluarga. Sementara itu ada beberapa alasan yang tidak benar untuk investasi: 1)
ketamakan. 2) Iri hati 3) Kesombongan. 4) Kebodohan. Ada banyak motif yang salah untuk
investasi. Hasil dari masing-masing motif yang salah itu ialah kekhawatiran, frustasi dan
akhirnya matinya nilai-nilai rohani. (band. Luk. 16:13) (Burkett, 2006, p. 134) Perumpamaan tentang Talenta (Mat. 25:14-30) Perumpamaan tentang Talenta dalam Matius 25:14-30 ini sesungguhnya
berhubungan dengan kedatangan Tuhan Yesus, namun demikian dari dalamnya dapat
ditemukan prinsip-prinsip manajemen keuangan (Blue., 2016, p. 24) karena berbicara
mengenai tiga orang yang dipercayakan harta berupa talenta oleh tuannya. Masing-masing
dipercayakan kepada mereka lima, tiga dan satu talenta sesuai dengan kesanggupan mereka
dalam pandangan tuannya (ayat 15). Lalu dua hamba yang dipercayakan lima dan tiga talenta menginvestasikannya
sehingga menghasilkan laba dua kali lipat banyaknya. Sementara itu yang dipercayakan satu
talenta menguburkan uangnya di dalam tanah sehingga tidak menghasilkan apapun. Ketika tuannya datang, ia meminta pertanggungjawaban atas harta yang
dipercayakan kepada mereka. Menurut tuannya, kedua hamba pertama adalah baik dan setia
(Mat. 15:21, 23), sebab mereka mengelola dengan sebaik-baiknya apa yang dipercayakan
untuk kepentingan tuannya sehingga mereka mendapatkan kepercayaan yang lebih dan
mendapat kebahagiaan yang sama dengan tuannya. Namun hamba ketiga didapati sebagai hamba yang jahat dan malas. Ia berpendapat
bahwa tidak ada gunanya mengusahakan laba yang menguntungkan tuannya sehingga ia
menerima hukuman yang setimpal. 179 Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) Prinsip-prinsip yang dapat diambil dari perumpamaan ini adalah sebagai berikut:
a) Allah adalah pemilik segala sesuatu Prinsip-prinsip yang dapat diambil dari perumpamaan ini adalah sebagai berikut:
a) Allah adalah pemilik segala sesuatu Seorang penatalayanan keuangan adalah hamba yang dipercayakan harta oleh
tuannya (ayat 14). Hamba bukanlah pemilik karena segala sesuatu adalah milik tuannya. Implikasinya adalah apapun yang tuannya inginkan harus dilakukan. Sebagai seorang hamba
hanya perlu bertanggung-jawab mengelola dan kapanpun tuannya akan meminta
pertanggungjawaban seorang hamba harus siap. (Blue., 2016, p. 24) Manajemen Keuangan mutlak wajib dilakukan karena Allah adalah pemilik segala
sesuatu. Semua harta milik di dunia
ini adalah milik Allah yang harus
dipertanggungjawabkan. Seorang penatalayan bertanggung-jawab kepada Allah dan Allah
akan meminta pertanggungjawaban. (Ward, 1993, p. 131). c) Sikap bertanggung-jawab dan kesetiaan Maksud dari perumpamaan ini adalah untuk mencerminkan sikap-sikap dan
kesetiaan para investor tanpa kehadiran atau pengawasan majikan mereka. Hal ini
mengingatkan kita bahwa tempat dan pelayanan orang percaya di sorga akan ditentukan oleh
tanggung jawab dan kesetiaan dalam kehidupan dan pelayanan di bumi (band. Mat. 25:29). Talenta memberikan gambaran tentang kemampuan, waktu, sumber daya dan
kesempatan untuk melayani Allah. Allah mempercayakan sesuatu kepada kita dan kita
bertanggung jawab untuk mengelolanya sebijaksana mungkin (Sabda Online Bible Versi
Indonesia, 1999c). Jadi manajemen keuangan harus dikerjakan dengan sikap yang penuh
dengan tanggung jawab dan kesetiaan kepada Allah. d) Upah Yesus menyatakan suatu prinsip penting yang berkaitan dengan upah dan kedudukan
orang percaya di dalam sorga. Upah yang diterima, warisan dan kedudukan di sorga akan
sebanding dengan pengabdian yang sedang dikerjakan sekarang ini untuk kerajaan Allah. (Luk. 22:24-30) (Sabda Online Bible Versi Indonesia, 1999b). Mereka yang setia dalam pelayanan dan yang telah berperan serta dalam pekerjaan-
Nya di bumi akan diberi upah di kerajaan yang akan datang. Mereka bahkan akan diberi
tugas yang lebih besar (Wahyu 21:1). Mereka yang memiliki tingkat kesetiaan yang lebih
rendah akan menerima lebih sedikit kedudukan dan tanggung jawab (Sabda Online Bible
Versi Indonesia, 1999a). 180 Jadi prinsip Manajemen Keuangan dalam perumpamaan tentang talenta ini adalah
sebagai berikut: 1) Manajemen Keuangan harus dilaksanakan dengan bertanggung-jawab
karena Allah adalah pemilik segala sesuatu yang akan meminta pertanggungjawaban atas
harta yang dipercayakan. 2) Investasi adalah bagian dari manajemen yang harus dikerjakan
dengan sikap dan alasan yang benar. 3) Manajemen Keuangan harus dikerjakan dengan sikap
yang penuh dengan tanggung-jawab dan kesetiaan kepada Allah. 4) Upah dalam Kerajaan
Allah yang akan datang akan diberikan bagi setiap mereka yang melakukan tugas
Manajemen Keuangan dengan setia. Bendahara Yang Tidak Jujur (Luk. 16:1-14) Perumpamaan ini adalah perumpamaan yang sering disalahpahami. Pertanyaan
dasar yang diajukan adalah: Bagaimana m ungkin Yesus memuji bendahara atau pengelola
(steward) yang tidak jujur ini? Bagaimana mungkin Yesus menggunakan orang yang tidak
jujur sebagai contoh kecerdikan, yaitu, sebagai orang yang bertindak dengan memikirkan
tentang masa depannya jauh ke depan? (BENDAHARA YANG TIDAK SETIA - Cahaya
Pengharapan Ministries, n.d.) Yesus bukan sedang memuji ketidakjujuran orang itu, melainkan kemampuannya
untuk melihat ke depan dan membuat perencanaan yang bijaksana. Jawaban ini tetap
memperhitungkan keberatan yang diajukan tentang pemakaian ilustrasi dari orang yang
tidak jujur walaupun bukan ketidak jujurannya yang sedang dipuji (BENDAHARA YANG
TIDAK SETIA - Cahaya Pengharapan Ministries, n.d.). Di ayat yang pertama, sang majikan mengajukan tuduhan kepada bendaharanya
bahwa ia telah menghambur-hamburkan kekayaan sang majikan (BENDAHARA YANG
TIDAK SETIA - Cahaya Pengharapan Ministries, n.d.). Kata menghamburkan disini
digunakan kata Yunani διασκορπίζων, yang artinya to dissipate - berfoya-foya,
menghamburkan. (Strong; 2001: 66). Pemborosan berbeda dengan ketidakjujuran. Pemborosan tidak selalu didasari oleh ketidakjujuran. Pemborosan lebih merupakan suatu
kecerobohan; kegagalan dalam mengelola sesuatu. g g
g
Pada ayat 8, kata "tidak jujur" dalam bahasa Yunaninya adalah ἀδικί yang artinya
unrighteousness, iniquity, unjust, wrong - tidak benar, perbuatan salah, tidak adil, salah. (Strong, 2001:6). Dengan demikian, makna sebenarnya adalah perbuatan yang salah
(wrongdoing) atau telah melakukan sesuatu yang salah, suatu ungkapan yang mempunyai
arti yang luas. Maka jelaslah bawa pengelolaan atau penatalayanan yang tidak benar menjadi
inti dalam perumpamaan ini sehingga bendahara tersebut dipecat oleh tuannya. Semua orang percaya merupakan para pengurus yang bekerja bagi Allah karena
"telah dibeli dan harganya telah lunas dibayar” (1 Kor. 6:20). Sebagai orang yang "telah
dibeli dan harganya telah lunas dibayar”, orang Kristen bukan hanya sekedar menjadi
percaya. Namun menjadi milik Allah dan tidak lagi menjalani hidup demi diri sendiri
melainkan menjalani hidup dalam tugas dan panggilan-Nya menjadi pengurus atau
penatalayan dalam bidang masing-masing sesuai dengan apa yang dikaruniakan-Nya. Di
samping itu, orang percaya diberi otoritas untuk melakukan penatalayanan dengan benar dan
bertanggung jawab sehingga tidak boleh disalahgunakan seperti bendahara yang tidak benar
itu. Lebih lanjut Yesus menjelaskan dalam perikop berikutnya terkait dengan kesetiaan
pada perkara kecil (Luk. 16:10-13) sehingga jelaslah bahwa bendahara yang tidak jujur
tersebut tidak setia dalam mempertanggungjawabkan keuangan yang dipercayakan tuannya
kepadanya. Suatu kepercayaan dilihat dari kesetiaan seseorang melakukan hal-hal benar
dalam perkara-perkara kecil. Hal kecil itu adalah mengenai uang. Anggaran (Luk. 14:28-30) Anggaran adalah bagian dari perencanaan keuangan. Lukas 14:28-30 dengan jelas
menyatakan mengenai anggaran yang menjadi bagian dari perencanaan dalam hal keuangan
(Luk. 14:28-30). Kata anggaran dalam bahasa Yunani digunakan dengan kata ψηφίζει dari akar kata
qhfov yang artinya adalah to use pebbles in enumeration, to count - menggunakan kerikil
untuk menghitung, menghitung. (Strong, 2001, p. 275) Jadi, dalam konteks ini adalah
penghitungan biaya atas proyek pembangunan menara. Latar belakang ayat tersebut adalah ketika Yesus dalam perjalanan dan sedang
berbicara mengenai bagaimana harus mengikut Dia. Mengikut Dia diumpamakan sebagai
seorang yang membangun sebuah menara, Menara disini menggambarkan suatu pekerjaan
atau proyek yang besar sehingga memerlukan suatu perencanaan dan perhitungan yang
matang dalam mengerjakannya. Yesus menunjukkan betapa pentingnya anggaran sebagai bagian dari perencanaan
untuk mencapai sasaran rohani, yaitu mengikut Dia karena mengikut Dia memiliki standar
nilai yang sangat tinggi. Jika pada akhirnya orang tidak mampu mencapainya maka "jangan-
jangan semua orang yang melihatnya, mengejek dia" (Luk. 14:29). Demikian pula dalam manajemen keuangan, sebuah proyek memerlukan
perencanaan dan perhitungan yang matang supaya nama Tuhan tidak dipermalukan. Bahkan
Charles G. Ward menyatakan bahwa kurang penganggaran menjadi penyebab utama
masalah keuangan. (Ward, 1993, p. 130) Petrus Octavianus dalam bukunya Manajemen dan Kepemimpinan Menurut Wahyu
Allah juga melontarkan suatu pernyataan yang menunjukkan pentingnya perencanaan:
Mengapa kita harus membuat perencanaan dalam menangani pekerjaan rohani? Secara
langsung menjawab, supaya pekerjaan itu berjalan teratur. Sebab Allah orang Kristen tidak
menghendaki kekacauan, melainkan damai sejahtera. (band. 1 Kor. 14:33) Dalam suratnya
kepada jemaat di Efesus, Rasul Paulus mengingatkan “jadilah penurut-penurut Allah.” (Ef. 5:1) (Ward, 1993, p. 130) Namun demikian anggaran menjadi perdebatan bagi beberapa pihak. Satu pihak
mengatakan tidak perlu adanya anggaran karena sebuah anggaran akan menghapus unsur
iman dan membawa gereja atau lembaga rohani turun ke tingkat dunia. Di lain pihak,
masalah anggaran disarankan oleh orang-orang yang ingin mengelola sebuah gereja atau
lembaga rohani seakan-akan sebuah perusahaan. Kedua ekstrem tersebut secara Alkitabiah
adalah salah. Anggaran tidak mencerminkan kekurangan iman, tetapi malahan
mencerminkan perencanaan yang baik (Luk. 14:28-30). Tetapi anggaran itu tidak boleh
mengesampingkan sasaran rohani Allah. (Burkett, 2006, p. 117) Oleh karena itu prinsip manajemen keuangan dalam bagian ini adalah mengadakan
perhitungan atau membuat anggaran dalam setiap proyek yang akan kita kerjakan tanpa
mengesampingkan sasaran rohani Allah supaya kita dapat menyelesaikan setiap proyek
dengan baik dan nama Tuhan dipermuliakan. 181 Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) Cara Hidup Jemaat Mula-Mula (Kis. 2:44-45; 4:32-37) Jemaat yang mula-mula memperlihatkan penatalayanannya dengan menyerahkan
harta miliknya untuk diurus oleh para rasul (dan kemudian oleh para diaken) untuk dibagi-
bagikan sesuai dengan keperluan orang-orang percaya (Kis. 2:44-45; 4:32-37; 6:1-7)
(Packer, J.I., Merrill C. Tenney & William White, 2003, pp. 680–681). Hati mereka sangat
terbuka kepada Roh Kudus dan bersedia bertekun dalam pengajaran rasul-rasul. Mereka
berkumpul untuk memecahkan roti dan berdoa sehingga mereka hidup tidak dikuasai
kedagingan melainkan oleh Roh Kudus. Mereka adalah orang Kristen yang bersatu dan
segala harta milik mereka adalah milik bersama. Mereka menjual harta miliknya, lalu
membagi-bagikannya kepada semua orang sesuai dengan kebutuhan masing-masing. Inilah
cara mereka mengelola keuangan mereka (Kis 2:43-45; 4:32). Secara harfiah keadaan tersebut pada jaman sekarang ini sulit untuk diterapkan. Namun prinsip pengelolaan keuangan untuk keadilan dan saling tolong menolong dapat
diterapkan. Kisah Para Rasul 4:34-35 dengan jelas menyatakannya: Sebab tidak ada
seorangpun yang berkekurangan di antara mereka; karena semua orang yang mempunyai
tanah atau rumah, menjual kepunyaannya itu, dan hasil penjualan itu mereka bawa dan
mereka letakkan di depan kaki rasul-rasul; lalu dibagi-bagikannya kepada setiap orang sesuai
dengan keperluannya. Hal yang dikemukakan oleh Lukas sebagai penulis Kisah Para Rasul di atas
menyatakan bahwa orang percaya melepaskan hak atas semua kekayaan atau harta mereka. Mereka mempersembahkannya bagi Tuhan tanpa batas, tidak lagi menghitung jumlah dan
prosentase bagi Tuhan. Dalam manajemen keuangan, harus disadari benar bahwa kekayaan atau harta yang
dipercayakan untuk dikelola adalah milik Tuhan dan sebagai pengelola tidak berhak
mengelola sewenang-wenang sebagai milik melainkan demi tujuan yang empunya kekayaan
atau harta tersebut. Bendahara Yang Tidak Jujur (Luk. 16:1-14) Jika seseorang tidak dapat
mengurus atau mengelola keuangan, ia tidak layak dipercaya untuk hal-hal yang lebih besar,
yaitu Injil atau diri Yesus sendiri (band. 2 Kor. 4:7; Kol. 2:3). Suatu kepercayaan itu mahal harganya. Kekudusan adalah panggilan untuk hidup
bertanggungjawab (Hill, 1997, p. 256) khususnya bertanggungjawab terhadap pengelolaan
keuangan. Ketika penatalayanan keuangan dapat dipercayai dalam keuangan maka
kepercayaan akan terus bertambah. Sebaliknya jika penatalayan keuangan tidak dapat
dipercaya maka tidak akan ada lagi kepercayaan padanya. Pdt. DR. Petrus Octavianus menyatakan dalam bukunya bahwa bila seorang
pemimpin kehilangan kepercayaan dalam keuangan, itu berarti pemimpin itu sudah gagal. Bahkan merupakan kegagalan total. Dan seringkali kegagalan seorang hamba Tuhan terletak
pada ketidakmampuannya mengurus keuangan. (Petrus Octavianus, 2007, pp. 156–157) 182 Prinsip manajemen keuangan pada bagian ini adalah: 1) setiap penanggung keuangan harus
memiliki rasa tanggung jawab terhadap pengelolaan keuangan yang dipercayakan
kepadanya; 2) setiap penanggung jawab keuangan harus memiliki integritas dalam dirinya,
dapat diandalkan dan tidak menyalahgunakan kepercayaan yang diberikan kepadanya; 3)
Kekudusan menjadi bagian yang penting dalam manajemen keuangan; 4) perencanaan
harus menjadi bagian dari manajemen keuangan yang harus dilaksanakan tetapi bukan untuk
kepentingan dan keselamatan diri atau untuk melakukan sesuatu yang tidak benar melainkan
dalam tanggung jawab pengelolaan yang diberikan Tuhan kepada kita; 5) Kecerdikan harus
menjadi bagian dalam menggunakan pikiran untuk memikirkan setiap masalah dalam
manajemen keuangan tetapi tetap dalam koridor takut akan Allah. Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) Paulus melaksanakan dengan tekun pengumpulan derma untuk Yerusalem pada
perjalanan misinya yang ketiga sambil menjangkau Makedonia, Akhaya dan Asia Kecil. Tujuan terakhir adalah ibukota kekaisaran Romawi, yaitu Roma, tetapi sebelumnya Paulus
bertekad untuk menyerahkan hasil kegiatan persembahan itu kepada umat induk di
Yerusalem (band. Rm. 15:25-28). (Simamora., 2008, p. 22) p
Seluruh konteks 2 Korintus 8 dan 9 dengan jelas menekankan bantuan materi yang
dikumpulkan jemaat-jemaat misi Paulus untuk mereka yang tinggal di antara orang-orang
kudus, yang telah jatuh miskin sehingga merekalah yang perlu dilayani dengan harta jasmani
(Rm. 15:27b). Pengumpulan dana bantuan itu pernah tertunda dan berhenti di Korintus karena
timbulnya konflik yang mengerikan antara Paulus dan lawan-lawannya dengan tuduhan-
tuduhan yang keras bahwa Paulus mengambil untung dana bantuan tersebut. Konflik
tersebut akhirnya diredakan dengan perantaraan Titus yang dapat memberitahukan kepada
Paulus bahwa jemaat di Korintus kembali memihak kepadanya. Penginjilan Paulus di Asia
Kecil rupanya tidak menghasilkan suatu sumbangan yang hendak diadakan Paulus bersama
dengan delegasinya ke Yerusalem. (Simamora., 2008, p. 22) Oleh karena tekadnya mengumpulkan bantuan dan tantangan yang timbul dari pihak-
pihak Yahudi, khususnya dari kalangan umat bersunat di Yudea maka Paulus meminta
kepada jemaat di Roma untuk bersama-sama bergumun dengan Paulus dalam doa supaya
Paulus dilindungi dari orang-orang yang tidak taat di Yudea, dan supaya pelayanan Paulus
disambut dengan baik oleh orang-orang kudus di Yerusalem (Rm. 15:30). Paulus tiba di Yerusalem pada masa perayaan Pentakosta. Namun Alkitab tidak
menjelaskan diterima-tidaknya dana bantuan itu oleh orang-orang
kudus yang miskin. (Simamora., 2008, pp. 22–23) Ada beberapa prinsip yang perlu dicermati dalam pengumpulan dana bantuan in Ada beberapa prinsip yang perlu dicermati dalam pengumpulan dana bantuan ini: 1) Paulus menghargai peran utama jemaat induk dalam sejarah keselamatan sehingga
persembahan itu menyatakan rasa terima kasih atas berkat yang datang melalui Israel dan
dari jemaat Kristen Yahudi di kota suci Yerusalem sambil menyebarnya kepada semua
bangsa. Dengan demikian, persembahan Paulus untuk orang miskin bertekad untuk turut
memupuk kesatuan dan persatuan jemaat Kristen bukan Yahudi dengan orang-orang Kristen
Yahudi yang bersama-sama mempermuliakan Allah dalam gereja yang satu saja
(Simamora., 2008, p. 2). 2) Paulus dengan jelas menyatakan prinsip memberi dalam 2 Korintus 8:12 bahwa
jika orang percaya rela untuk memberi, maka pemberian itu akan diterima. Pemberian itu
berdasarkan apa yang ada, bukan berdasarkan apa yang tidak ada pada diri orang percaya. Kerelaan merupaka bagian yang penting dalam memberi. Pengumpulan Bantuan oleh Paulus Pada konsili rasuli pada tahun 49, Paulus dan sokoguru jemaat induk Yahudi di
Yerusalem menyepakati agar Paulus menginjili orang-orang bukan Yahudi dan tokoh-tokoh
jemaat Yerusalem menuju kepada orang-orang yang bersunat. Di saat itu pula ada
kesepakatan untuk mengumpulkan persembahan dari jemaat-jemaat hasil misi Paulus yang
ditentukan untuk membantu orang-orang miskin dalam jemaat induk Yahudi di Yerusalem
(Gal. 2:9). Di dalam Kisah Para Rasul 11:29-30 disebutkan bahwa para murid memutuskan
untuk mengumpulkan sumbangan sesuai dengan kemampuan mereka dan mengirimkannya
kepada saudara-saudara yang tinggal di Yudea. Hal itu mereka lakukan juga dan
mengirimkannya kepada penatua-penatua dengan perantaraan Barnabas dan Saulus. (Simamora., 2008, p. 21,26) 183 Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) Hal ini juga ditekankan kembali
dalam 2 Korintus 9:7. Paulus mendorong mereka untuk berani memberi karena Allah
sanggup melimpahkan segala kasih karunia supaya orang yang memberi senantiasa cukup
di dalam segala sesuatu dan lebih di dalam segala kebajikan." (2 Kor. 9:8). 3) Bantuan kepada orang-orang miskin tersebut dimaksudkan supaya ada
keseimbangan dimana orang yang berkelebihan mencukupkan orang yang berkekurangan. Paulus menunjukkan bahwa keseimbangan itu adalah kehendak Allah dengan mengutip apa
yang ditulis oleh Musa: "Orang yang mengumpulkan banyak, tidak kelebihan dan orang
yang mengumpulkan sedikit, tidak kekurangan" (2 Kor. 8:14-15). 4) Paulus menyatakan bahwa suatu pemberian bukan hanya mencukupkan
keperluan-keperluan orang-orang kudus saja melainkan juga memperkaya orang yang
memberi dalam segala macam kemurahan hati serta membangkitkan ucapan syukur kepada
Allah dengan limpahnya (2 Kor. 9:11-12). 5) Memberi adalah penting bagi Allah, dan Dia menaruh perhatian mengenai
bagaimana seseorang memberi: apakah dengan sedikit sukacita atau dengan sukacita 5) Memberi adalah penting bagi Allah, dan Dia menaruh perhatian mengenai
bagaimana seseorang memberi: apakah dengan sedikit sukacita atau dengan sukacita 184 nuhnya. "Karena Allah mengasihi orang yang memberi dengan sukacita" (2 Kor. 9:7b)
n Avanzini, 1985, p. 91). sepenuhnya. "Karena Allah mengasihi orang yang memberi dengan sukacita" (2 Kor. 9:7b)
(John Avanzini, 1985, p. 91). sepenuhnya. "Karena Allah mengasihi orang yang memberi dengan sukacita" (2 Kor. 9:7b)
(John Avanzini, 1985, p. 91). p
6) Paulus melakukan pengumpulan dana bantuan itu dengan memberikan petunjuk-
petunjuknya dengan jelas (1 Kor. 16:2-3). Pada bagian ini terlihat kesungguhan usaha
Paulus yang mengupayakan bantuan untuk jemaat di Yerusalem itu terkumpul. Selain dari
segi pemahaman teologis, Paulus juga menginvestasikan pikiran agar organisasi pemberian
itu tertib dan lancar. Ia mengaturnya secara rinci dan menyerahkan pelaksanaan selanjutnya
kepada jemaat yang bersangkutan (Simamora., 2008, p. 5). 7) Paulus memiliki kesungguhan yang luar biasa dalam menghadapi tantangan yang
ada: di Galatia, dari kelompok Yudaisme, di Korintus dari nabi-nabi palsu, penganut
antusiasme rohani. Akibatnya, pengumpulan sumbangan tertahan dan Paulus harus bekerja
keras untuk menyiapkan kembali aksi pendermaan itu sampai sangat berhasil di kawasan
Eropa. Dalam surat-suratnya: Galatia, 1 dan 2 Korintus dan Roma menggemakan
kesungguhan usahanya itu (Simamora., 2008, p. 5). Dan secara jelas dalam 2 Korintus 9:13-
15 Paulus menyatakan bagaimana Allah dimuliakan karena hasil dari perjuangan. Maka dari itu fundraising adalah bagian dari manajemen keuangan dalam perspektif
iman kristen dengan memperhatikan apa yang telah Paulus lakukan yaitu berbagi beban
kepada jemaat yang dilayaninya. Pajak Salah satu pernyataan Yesus yang paling banyak diingat adalah memberikan kepada
Kaisar dan kepada Allah sesuai dengan apa yang yang wajib diberikan. (Mat. 22:17; Mrk. 12:13-17; Luk. 20:25). Ini adalah perintah yang jelas bagi kita untuk membayar pajak kita. Yang terpenting adalah kepatuhan kita. Kepatuhan kepada Undang-Undang Negara,
disamping kepada hukum Tuhan. (Briner, 1997, p. 97) Lebih lanjut dalam Roma 13:7 menyatakan kepada kita untuk membayar pajak dan
cukai kepada orang yang berhak menerimanya. Lalu rasa takut dan hormat kepada orang
yang berhak menerimanya. Paulus menggariskan dua bidang kewajiban. Yang pertama,
adalah tentang keuangan dan yang kedua, adalah tentang sikap. (Getz, 2008, p. 246) Orang Kristen tidak hanya harus membayar pajak tetapi mereka juga harus
melakukannya dengan pemahaman yang benar. Kalau kita harus menghargai seseorang,
maka kita harus melakukannya. Kalau kita harus menghormati seseorang, kita juga harus
melakukannya. Yesus memberikan contoh mengenai hal ini. Ia tidak setuju dengan Herodes
Antipas, pemerintah di Galilea dan Kaisar Tiberius, pemerintah di Kekaisaran Romawi. Dalam banyak hal, nilai-nilai yang mereka anut bertolak belakang dengan nilai-nilai-Nya. Tetapi Kristus masih menghargainya orang-orang ini karena kedudukan yang ditetapkan
Allah atas mereka. Dan satu cara untuk menunjukkan penghargaan-Nya itu adalah dengan
membayar pajak. (Getz, 2008, pp. 246–257) Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) Fundraising tidak ditujukan untuk diri sendiri melainkan
untuk pekerjaan Tuhan yang Tuhan bebankan kepada hamba-hamba-Nya dengan
memberikan dasar teologi yang jelas, kerja keras, perencanaan, komunikasi, sosialisasi yang
baik dan petunjuk-petunjuk yang jelas. HASIL DAN PEMBAHASAN Berdasarkan analisa yang dilakukan penulis maka ditemukan hasil sebagai berikut: METODE PENELITIAN Metodologi Penelitian yang digunakan oleh penulis adalah metode penelitian
kualitatif. Penelitian Kualitatif adalah penelitian yang dianalisis tanpa menggunakan Teknik
statistik dan data penelitian tersebut dinyatakan dalam bentuk verbal. (Penyusun, 1997, p. 8)
Metode Penelitian kualitatif sering disebut metode penelitian naturalistik karena
penelitiannya dilakukan pada kondisi yang alamiah (natural setting); disebut juga sebagai
metode etnographi, karena pada awalnya metode ini lebih banyak digunakan untuk 185 Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) penelitian bidang antropologi budaya; disebut sebagai metode kualitatif, karena data yang
terkumpul dan analisisnya lebih bersifat kualitatif. (Sugiyono, 2012, p. 8) Ada beberapa istilah yang digunakan untuk penelitian kualitatif, yaitu penelitian atau
inkuiri naturalistik atau alamiah, etnografi, interaksionis simbolik, perspektif ke dalam,
etnometodologi, “the Chicago School”, fenomenologis, studi kasus, interpretative, ekologis
dan deskriptif. (Moleong, 2010, p. 3). Istilah-istilah tersebut merupakan keragaman
paradigma dalam penelitian kualitatif. Menurut Moleong, jika seseorang mengadakan
penelitian kualitatif, ia perlu mendalami paradigma yang menyertainya. Paradigma adalah
kumpulan longgar dari sejumlah asumsi yang dipegang bersama, konsep atau proporsi yang
mengarahkan cara berpikir dan penelitian. (Moleong, 2010, pp. 48–49) g
p
p
g
pp
Ada bermacam-macam paradigma, tetapi yang mendominasi ilmu pengetahuan
adalah scientific paradigm (paradigma keilmuan atau paradigma ilmiah) dan naturalistic
paradigm atau paradigma alamiah. Paradigma ilmiah bersumber dari pandangan positivisme
sedangkan paradigma alamiah bersumber pada pandangan fenomenologis. (Moleong, 2010,
pp. 50–51). Para positivis mencari fakta dan penyebab fenomena sosial dan kurang
mempertimbangkan keadaan subjektif individu. Sedangkan fenomenologi berusaha
memahami perilaku manusia dari segi kerangka berpikir maupun bertindak orang-orang itu
yang dibayangkan atau dipikirkan oleh orang-orang itu sendiri. (Moleong, 2010, pp. 51–52)
Penulis akan menggunakan paradigma alamiah atau naturalistic paradigm untuk penelitian
ini. Penerapan Prinsip Manajemen Keuangan Dalam Perspektif Iman Kristen 2. Penerapan Prinsip Manajemen Keuangan Dalam Perspektif Iman Kristen Mengenai penerapan prinsip melakukan tujuan Manajemen Keuangan Dalam
Perspektif Iman Kristen, sebagian Lembaga Kristen merasa sedang dalam proses ke arah
melakukannya mengingat masih ada kekurangan di sana sini yang belum dapat
disempurnakan. Mengenai penerapan prinsip perencanaan, Lembaga Kristen sudah menerapkannya
karena memiliki sistem yang mengharuskan perencanaan keuangan dibuat setiap tahunnya,
namun terbatas pada perencanaan teknis dan perencanaan jangka pendek. Perencanaan
belum terprogram dengan baik, Lembaga Kristen hanya membuat perencanaan jangka
panjang jika diminta. Perencanaan yang kurang matang akan menyebabkan arah tindakan
tidak fokus pada pencapaian tujuan yang akan datang. Pada penerapan fungsi pengorganisasian yang terkait dengan keuangan, belum
terorganisir dengan baik mengingat perencanaan belum dilakukan dengan baik juga. Pengorganisasian Keuangan hanya tampak dalam melakukan pengeluaran uang operasional
saja bahkan beberapa kondisi tidak disertai dengan ketersediaan dana yang cukup untuk
melaksanakannya sehingga kurang pengorganisasian di dalamnya. y
gg
g p
g
g
y
Fungsi pengawasan merupakan suatu kegiatan yang dilakukan untuk memastikan
bahwa perencanaan yang telah disusun dapat terlaksana dengan baik sesuai dengan arah dan
tujuan yang telah ditetapkan. Pengawasan meliputi perbandingan kinerja aktual dengan
rencana-rencana untuk mengevaluasi efektivitas rencana, mengidentifikasi kelemahan-
kelemahan secara lebih awal dan mengambil tindakan-tindakan korektif bila diperlukan. Dalam hal ini Lembaga Kristen telah melakukannya dalam keterbatasan yang ada. Jika hal
tersebut diatas dilakukan sepenuhnya maka kinerja manajemen keuangan Lembaga Kristen
akan menjadi baik. Mengenai prinsip pengendalian, sebagian besar Lembaga Kristen sudah
melakukannya karena menyadari sepenuhnya perlunya menggunakan uang Tuhan sebaik
mungkin, dengan penuh tanggung jawab dan ketundukkan kepada pengaturan lembaga. Terkadang dengan menghadapi keterbatasan dana juga merupakan faktor yang membuat
pengendalian keuangan menjadi bagian yang tidak terelakkan untuk dikerjakan. Jika fungsi
pengendalian ini diterapkan maka pengeluaran akan efektif dan efisien, sehingga berdampak
pada kinerja Lembaga Kristen secara keseluruhan. Sama seperti pada bagian perencanaan, prinsip anggaran juga sudah dilakukan
karena Lembaga-Lembaga Kristen memiliki aturan untuk menerjemahkan setiap
perencanaan keuangan ke dalam angka-angka yang realistis, yang diajukan setiap tahunnya
dan kemudian di break down dalam permohonan dana bulanan, mingguan dan harian. Inilah
yang membuat arah dan tujuan satuan kegiatan menjadi jelas dan dikoordinasikan dengan
pusat, apakah sudah searah dan setujuan dengan lembaga. Mengenai fungsi reporting, peraturan lembaga mengharuskan penanggung jawab
keuangan mempertanggungjawabkan setiap penggunaan uang sehingga penerapan prinsip
reporting menjadi bagian yang tidak terelakkan untuk dikerjakan oleh setiap penanggung
jawab keuangan dan pengguna dana. Penerapan Prinsip Manajemen Keuangan Dalam Perspektif Iman Kristen Hal ini membuat lembaga mendapatkan gambaran yang
jelas mengenai perkembangan-perkembangan satuan kegiatan atau kegiatan-kegiatan
tertentu dan mendapatkan informasi-informasi yang diperlukan. Untuk tindakan selanjutnya
serta evaluasi terjadi hasil yang diharapkan. 1. Pemahaman mengenai Manajemen Keuangan dalam Perspektif Iman Kristen Lembaga-Lembaga Kristen memahami perlunya otoritas tertinggi, yaitu Alkitab
dalam setiap pengambilan keputusan keuangan dan menggunakan disiplin ilmu keuangan
untuk memenuhi kaidah-kaidah yang ditetapkan oleh peraturan pemerintah. Pada umumnya Lembaga-Lembaga Kristen memahami manajemen keuangan
sebagai pengelolaan di bidang keuangan dengan pengelolaan yang efisien, pencapaian dan
pelaksanaan. Ini menunjukkan kurang lengkapnya pemahaman manajemen keuangan yang
dimiliki dan dengan apa yang dimaksud dengan manajemen keuangan, yaitu keseluruhan
aktivitas manajemen yang bersangkutan dengan usaha untuk mendapatkan dana dan
menggunakan serta mengalokasikan dana tersebut sesuai dengan prinsip Alkitab. Ini
menyebabkan Lembaga Kristen kurang mengerjakan tugas dan tanggung jawab pengelolaan
secara profesional. Sementara itu, Lembaga Kristen sangat memahami apa makna dalam perspektif iman
Kristen, yaitu berdasarkan Alkitab atau firman Allah atau dengan prinsip-prinsip rohani. Ini
menunjukkan bahwa Lembaga Kristen memiliki pengertian dasar dengan apa yang
dimaksud dalam penulisan ini. Keyakinan pelaku organisasi dalam Lembaga Kristen kepada Alkitab sebagai
sumber utama prinsip-prinsip manajemen keuangan dalam perspektif iman kristen sangat
tinggi, namun kurang memahami bagian-bagan Alkitab secara menyeluruh dan tidak secara
khusus dapat mengaitkannya dengan manajemen keuangan sehingga menemui kesulitan
dalam hal praktis implementasi dalam pelayanan. 186 SIMPULAN Manajemen Keuangan dalam Perspektif Iman Kristen adalah menemukan prinsip-
prinsip pengelolaan keuangan yang sesuai dengan Firman Allah. Pengelolaan yang sesuai
dengan prinsip Alkitab harus mendasari setiap pengambilan keputusan keuangan dan
penyelesaian masalah keuangan yang terjadi. Alkitab adalah pedoman hidup dalam setiap
bidang kehidupan termasuk hal-hal penting keuangan ada di dalamnya. Lembaga-Lembaga Kristen kurang memahami seutuhnya prinsip Manajemen
Keuangan dalam Perspektif Iman Kristen sehingga tidak dapat menerapkan pengelolaan
dengan baik pula. Kendala-kendala dalam penerapan prinsip-prinsip manajemen keuangan dalam
perspektif Iman Kristen harus ditindaklanjuti dengan memberikan pemahaman prinsip-
prinsip yang benar dan pelatihan-pelatihan khusus dalam disiplin ilmu keuangan. 3. Kendala Pelaksanaan Manajemen Keuangan dalam Perspektif Iman Kristen Lembaga Kristen menyadari tanggung jawab keuangan yang dipercayakan namun
menemui banyak kendala, sebagai berikut: Sumber daya manusia tidak menguasai Alkitab
secara menyeluruh terkait dengan pengelolaan keuangan dan tidak dilatih khusus untuk
mengelola dalam disiplin iman Kristen dan disiplin ilmu keuangan serta mengerjakannya 187 Missio Eclesiae| Volume 10, Nomor 2, (Oktober, 2021) dengan sikap yang benar; Lembaga-Lembaga Kristen kurang fokus dalam melakukan
manajemen keuangan karena kurangnya pemahaman mengenai manajemen keuangan dalam
perspektif iman Kristen. dengan sikap yang benar; Lembaga-Lembaga Kristen kurang fokus dalam melakukan
manajemen keuangan karena kurangnya pemahaman mengenai manajemen keuangan dalam
perspektif iman Kristen. DAFTAR PUSTAKA Armerding, H. T. (1989). Pola Hidup Kristen. Gandum Mas Armerding, H. T. (1989). Pola Hidup Kristen. Gandum Mas. Atmaja, L. S. (1988). Manajemen Keuangan. Penerbit Andi. Atmaja, L. S. (1988). Manajemen Keuangan. Penerbit Andi. Bastian, I. (2002). Akuntansi Yayasan dan Lembaga Publik. Penerbit Erlangga. BENDAHARA YANG TIDAK SETIA - Cahaya Pengharapan Ministries. (n.d.). Retrieved
October 31, 2021, from https://cahayapengharapan.org/bendahara-yang-tidak-setia/
Bl
R B & M (2016) M
Y
M
M
d P bli h Bastian, I. (2002). Akuntansi Yayasan dan Lembaga Publik. Penerbit Erlangga. BENDAHARA YANG TIDAK SETIA
C h
P
h
Mi i t i
( d ) R (
)
y
g
gg
BENDAHARA YANG TIDAK SETIA - Cahaya Pengharapan Ministries. (n.d.). Retrieve BENDAHARA YANG TIDAK SETIA - Cahaya Pengharapan Ministries. (n.d.). Retrieved
October 31, 2021, from https://cahayapengharapan.org/bendahara-yang-tidak-setia/
Blue., R. B. & M. (2016). Master Your Money. Moody Publisher. y
g
p
(
)
October 31, 2021, from https://cahayapengharapan.org/bendahara-yang-tidak-setia/
., R. B. & M. (2016). Master Your Money. Moody Publisher. y
g
p
October 31, 2021, from https://cahayapengharapan.org/bendahara-yang-tidak-seti
Bl
R B & M (2016) M
t
Y
M
M
d P bli h October 31, 2021, from https://cahayapengharapan.org/bendahara yang tidak setia/
Blue., R. B. & M. (2016). Master Your Money. Moody Publisher. Blue., R. B. & M. (2016). Master Your Money. Moody Publisher. Briner, B. (1997). The Management Methods of Jesus (Metode Manajemen Yesus). Professional Books. Burkett, L. (2006). Mengatur Keuangan Dengan Bijak (Y. K. Hidup (Ed.)). Candra, R. I. G. (1996). “Roh Manajemen,” Kairos, edisi no.40. Penebar Swadaya. Dainton, M. B. (1990). Harta Saya Milik Siapa? Yayasan Komunikasi Bina Kasih/OMF. Dayton., T. E. & E. R. (1989). Seni Manajemen Bagi Pemimpin Kristen. Yayasan Kalam
Hidup. Dainton, M. B. (1990). Harta Saya Milik Siapa? Yayasan Komunikasi Bina Kasih/OM (
)
y
p
y
Dayton., T. E. & E. R. (1989). Seni Manajemen Bagi Pemimpin Kristen. Yayasan Kalam
Hidup. Getz, G. (2008). Pedoman Lengkap Pendalaman Alkitab Tentang Uang dan Harta Milik. Yayasan Kalam Hidup. Handoko, T. H. (2003). Manajemen. Edisi 2 (B. Yogyakarta. (Ed.)). Hill, A. (1997). Bisnis Yang Benar. Yayasan Kalam Hidup. John Avanzini. (1985). Lebih Dari Cukup. YAKIN. Joseph - Studi Kamus - Alkitab SABDA. (n.d.). Retrieved October 31, 2021, from
https://alkitab.sabda.org/dictionary.php?word=Joseph#arts_Yusuf Kast, F. E. (1996). Organisasi dan Manajemen. Bumi Aksara. 6). Organisasi dan Manajemen. Bumi Aksar Moleong, L. J. (2010). Metode Penelitian Kualitatif, Edisi Revisi. Penerbit PT Remaja
Rosdakarya. Nainggolan, P. (2012). Manajemen Keuangan Lembaga Nirlaba. DAFTAR PUSTAKA Bina Int Nainggolan, P. (2012). Manajemen Keuangan Lembaga Nirlaba. Bina Integrasi edukasi Olan Hendrix. (1988). Management for Christian Leaders. Baker Book House. Packer, J.I., Merrill C. Tenney & William White, J. (2003). Ensiklopedi Fakta Alkitab -
Bible Almanac 1. Penerbit Gandum Mas. Packer, J.I., Merrill C. Tenney & William White, J. (2003). Ensiklopedi Fakta Alkitab -
Bible Almanac 1. Penerbit Gandum Mas. Penyusun, T. (1997). Dasar-Dasar Metodologi Penelitian. Penerbit Gandum Mas
Lembaga Penelitian IKIP MALANG. Penyusun, T. (1997). Dasar-Dasar Metodologi Penelitian. Penerbit Gandum Mas
Lembaga Penelitian IKIP MALANG. Petrus Octavianus. (1988). Peran dan Pemikiran. Departemen Literatur YPPII. (
)
p
Petrus Octavianus. (2007). Manajemen dan Kepemimpinan Menurut Wahyu Allah. 188 Departemen Literatur YPPII. Redaksi, T. (2001). Kamus Besar Bahasa Indonesia. Balai Pustaka. Rush, M. (2002). Manajemen Menurut Pandangan Alkitab. Penerbit Gandum Mas. Rush, M. (2002). Manajemen Menurut Pandangan Alkitab. Penerbit Gandum Mas. Simamora., U. B. & E. (2008). Memberi Dengan Sukacita - Tafsir dan Teologi Rush, M. (2002). Manajemen Menurut Pandangan Alkitab. Penerbit Gandum Mas. Simamora., U. B. & E. (2008). Memberi Dengan Sukacita - Tafsir dan Teologi
Persembahan. PT BPK Gunung Mulia. mamora., U. B. & E. (2008). Memberi Dengan Sukacita - Tafsir dan Teologi swanto. (1987). Pemrograman Linier Dasar Sisi Kuantitatif dari Manajemen. Penerbit
UAJY. Sosipater, K. (2010). Etika Perjanjian Baru. Suara Harapan Bangsa. Strong, J. (2001). The New Strong’s Expanded Dictionary of The Words in The Greek N
Testament. Thomas Nelson Publishers. Sugiyanto Wiryoputro. (2004). Dasar-Dasar Manajemen Kristiani. BPK Gunung Muli Sugiyono. (2012). Metode Penelitian Kuantitatif Kualitatif Dan R&D. Penerbit Alfabet Tomatala, Y. (1993). Penatalayanan Gereja Yang Efektif Di Dunia Modern. Penerbit
Gandum Mas. Walborn, R. C., & Chan, F. (2001). Stewardship and the Kingdom of God. Office of
Church Stewardship, Christian and Missionary Alliance. Ward, C.-A. T.-573-1-18-20211030. docxrle. G. (1993). Buku Pegangan Pelayanan. Persekutuan Pembaca Alkitab dan BPK Gunung Mulia. Widayati, I. (2012). Pengaruh Status Sosial Ekonomi Orang Tua, Pendidikan Pengelolaan
Keuangan Keluarga, dan Pembelajaran di Perguruan Tinggi Terhadap Literasi
Finansial Mahasiswa Fakultas Ekonomi dan Bisnis Universitas Brawijaya.(Tesis). Widayati, I. (2012). Pengaruh Status Sosial Ekonomi Orang Tua, Pendidikan Pengelolaan
Keuangan Keluarga, dan Pembelajaran di Perguruan Tinggi Terhadap Literasi
Finansial Mahasiswa Fakultas Ekonomi dan Bisnis Universitas Brawijaya.(Tesis). DISERTASI Dan TESIS Program Pascasarjana UM. Wilangga, Y. C. & M. H. (1996). Menang dalam Persaingan Gereja. Penebar Swadaya. Keuangan Keluarga, dan Pembelajaran di Perguruan Tinggi Terhadap Literasi
Finansial Mahasiswa Fakultas Ekonomi dan Bisnis Universitas Brawijaya.(Tesis). DAFTAR PUSTAKA DISERTASI Dan TESIS Program Pascasarjana UM. Wilangga, Y. C. & M. H. (1996). Menang dalam Persaingan Gereja. Penebar Swadaya. DISERTASI Dan TESIS Program Pascasarjana UM. Wilangga, Y. C. & M. H. (1996). Menang dalam Persaingan Gereja. Penebar Swadaya. 189
|
https://openalex.org/W4367854283
|
https://pubs.aip.org/aip/mre/article-pdf/doi/10.1063/5.0151844/17246089/038402_1_5.0151844.pdf
|
English
| null |
First-principles study on the conventional superconductivity of N-doped <i>fcc</i>-LuH3
|
Matter and radiation at extremes
| 2,023
|
cc-by
| 5,396
|
ABSTRACT Recently, room-temperature superconductivity has been reported in a nitrogen-doped lutetium hydride at near-ambient pressure
[Dasenbrock-Gammon et al., Nature 615, 244 (2023)]. The superconducting properties might arise from Fm3m-LuH3−δNε. Here, we sys-
tematically study the phase diagram of Lu–N–H at 1 GPa using first-principles calculations, and we do not find any thermodynamically
stable ternary compounds. In addition, we calculate the dynamic stability and superconducting properties of N-doped Fm3m-LuH3 using the
virtual crystal approximation (VCA) and the supercell method. The R3m-Lu2H5N predicted using the supercell method could be dynam-
ically stable at 50 GPa, with a Tc of 27 K. According to the VCA method, the highest Tc is 22 K, obtained with 1% N-doping at 30 GPa. Moreover, the doping of nitrogen atoms into Fm3m-LuH3 slightly enhances Tc, but raises the dynamically stable pressure. Our theoretical
results show that the Tc values of N-doped LuH3 estimated using the Allen–Dynes-modified McMillan equation are much lower than room
temperature. 24 October 2024 05:16:26 © 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license
(http://creativecommons.org/licenses/by/4.0/). https://doi.org/10.1063/5.0151844 AFFILIATIONS 1 State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
2Institute of High Pressure Physics, School of Physical Science and Technology, Ningbo University, Ningbo 315211, China a)Authors to whom correspondence should be addressed: duandf@jlu.edu.cn and cuitian@nbu.edu.cn First-principles study on the conventional
superconductivity of N-doped fcc-LuH3 Cite as: Matter Radiat. Extremes 8, 038402 (2023); doi: 10.1063/5.0151844
Submitted: 25 March 2023 • Accepted: 17 April 2023 •
Published Online: 2 May 2023 Zihao Huo,1
Defang Duan,1,a)
Tiancheng Ma,1 Zihan Zhang,1 Qiwen Jiang,1 Decheng An,1
Hao Song,2 Fubo Tian,1
and Tian Cui1,2a) Articles You May Be Interested In First-principles study on the electronic structure transition of β-UH 3 under high pressure Universal Fermi velocity in highly compressed hydride superconductors Pressure-induced reemergence of superconductivity in BaIr2Ge7 and Ba3Ir4Ge16 with cage structures
Matter Radiat. Extremes (May 2022) 24 October 2024 05:16:26 24 October 2024 05:16:26 Matter and
Radiation at Extremes RESEARCH ARTICLE scitation.org/journal/mre I. INTRODUCTION system at near-ambient pressure (∼1 GPa), with the highest Tc to
date of 294 K,22 thus achieving room-temperature superconduc-
tivity near ambient pressure. The authors of this study attributed
the room-temperature superconductivity in the Lu–N–H system to
Fm3m-LuH3−δNε, which can be regarded as Fm3m-LuH3 doped
with nitrogen atoms.i Hydrides have received much attention because of their excel-
lent superconductivities under pressure.1–4 In 2014, H3S was pre-
dicted to be a high-temperature superconductor with a Tc of
191–204 K,5 which was confirmed by the experimentally mea-
sured Tc of 203 K at 155 GPa.6,7 Following this success, several
superhydrides with high Tc values above 200 K, such as LaH10
(260 K, 170 GPa), YH6 (224 K, 166 GPa), YH9 (260 K, 201 GPa),
and CaH6 (215 K, 172 GPa), were predicted and synthesized.8–18
Recently, Song et al.19 comprehensively studied the Lu–H system
and predicted that Im3m-LuH6 should have a Tc of 273 K at
100 GPa. Extensive experimental research has been conducted on
the superconducting properties of lutetium hydrides under pres-
sure. Fm3m-LuH3 has been successfully synthesized and found to
have a Tc of 12 K at 122 GPa.20 Moreover, Pm3n-Lu4H23 has been
obtained, with a Tc of 71 K at 218 GPa.21 In particular, a very recent
experimental study has reported superconductivity in the Lu–N–H g
This report could represent a landmark event for the scientific
community, but many open questions surrounding this important
discovery remain unanswered, for example, the exact stoichiometry
and the positions of the hydrogen and nitrogen atoms. A subsequent
experimental observation indicates that the pressure-induced color
change of LuH2 is similar to that of N-doped lutetium hydride.23
In addition, a similar compound (LuH2±xNy) has been synthesized,
but no evidence for superconductivity at pressures ranging from
1 to 6 GPa has been found.24 Density functional theory (DFT)
calculations have been used to investigate the optical properties
of lutetium hydrides25 and the phase diagram of the Lu–N–H
system at 0, 5, and 10 GPa,26 but no thermodynamically stable 8, 038402-1 Matter Radiat. Extremes 8, 038402 (2023); doi: 10.1063/5.0151844
© Author(s) 2023 © Author(s) 2023 Matter and
Radiation at Extremes Matter and
Radiation at Extremes RESEARCH ARTICLE scitation.org/journal/mre Electronic structures, phonon spectra, and electron–phonon
coupling (EPC) were calculated using the QUANTUM ESPRESSO
(QE)33 package. The PAW pseudopotentials with valence electrons
1s1 for H, 2s22p3 for N, and 5s25p65d16s2 for Lu were used in the QE
package. I. INTRODUCTION The self-consistent electron density was evaluated using a
k-mesh of 20 × 20 × 20. The phonon spectra and EPC were calcu-
lated using a q-mesh of 5 × 5 × 5. The conventional superconducting
transition temperature was estimated using the A-D-M equation34 ternary compounds have been found. Therefore, an investigation
of the superconducting properties of N-doped lutetium hydrides is
necessary. In the work described in this paper, we performed a compre-
hensive first-principles study on the Lu–N–H system at 1 GPa. No
thermodynamically stable Lu–N–H ternary compounds were found
using the structure search method. We then analyzed the dynamic
stability and superconducting properties of N-doped Fm3m-LuH3
using the virtual crystal approximation (VCA) and the super-
cell method. Using the Allen–Dynes-modified McMillan (A-D-M)
equation, we found that the estimated highest Tc of N-doped LuH3
did not exceed 30 K, which is much lower than room tempera-
ture. In addition, we found that the doping of nitrogen atoms may
slightly enhance Tc but also increase the dynamically stable pressure
of LuH3. FIG. 1. (a) Ternary phase diagram (convex hull) of the Lu–N–H system at 1 GPa. The values of the enthalpy from the convex hull are shown next to the colored
circles. The circles with black solid boundaries denote the stable phases. (b)
Comparison of the XRD pattern from reported experimental data22 (lower black
curve) and the pattern calculated for P3m1-Lu2H2N at ambient pressure (upper
red curve). The inset shows the crystal structure of P3m1-Lu2H2N, with green,
gray, and pink spheres depicting Lu, N, and H atoms, respectively. II. COMPUTATIONAL DETAILS At 1 GPa, we performed a variable-composition crystal struc-
ture search in the Lu–N–H system with ∼10 000 structures using
the Ab Initio Random Structure Searching (AIRSS)27 code. We then
re-optimized the structures using the ab initio calculation from the
Cambridge Serial Total Energy Package (CASTEP).28 An on-the-fly
ultrasoft pseudopotential with valence electrons 1s1 for H, 2s22p3
for N, and 4f 145s25p65d16s2 for Lu was used, with a kinetic cutoff
energy of 800 eV. The Brillouin zone was sampled using a k-point
mesh of 2π × 0.03 Å−1 to make the enthalpy calculations converge
well to less than 1 meV/atom. Structural relaxations were performed
using projector-augmented wave (PAW)29,30 potentials, as imple-
mented in the Vienna Ab Initio Simulation Package (VASP),31 with
a cutoff energy of 600 eV. The exchange-correlation functional was
described using the Perdew–Burke–Ernzerhof generalized gradient
approximation.32 24 October 2024 05:16:26 We then prepared a conventional cell of Fm3m-LuH3, includ-
ing four formula units (f.u.). The calculations were performed for
a range of pseudostoichiometric Lu4HmN12−m, including Lu4H11N,
Lu2H5N, Lu4H9N3, and LuH2N, which correspond to nitrogen-
to-hydrogen atomic ratios of 0.09, 0.2, 0.33, and 0.5, respectively. Next, we calculated the formation enthalpies and superconducting
properties of these structures at 1, 10, and 50 GPa. The forma-
tion enthalpy of Lu4HmN12−m was calculated using the following
equation: H f = H(Lu4HmN12−m) −4H(LuH3) −mH(N) + mH(H). (1) (1) We investigated the pressure dependence of the superconduc-
tivity of Fm3m-LuH3 at 0.5%–2% doping with N using the VCA at
pressures below 100 GPa. The VCA was performed by generating
a virtual pseudopotential VVCA of H1−xNx, where VVCA = (1 −x)
VH + xVN. Furthermore, we calculated the equation of state for
LuH2.97N0.03, which is close to the elemental analysis data from pre-
vious experiments,22 using DFT and DFT + U (with U = 5.5 eV,
which has been used for metal mononitrides22). The result is shown
in Fig. S1 (supplementary material). The DFT result without the
Hubbard U effect fits better with the experimental data. Therefore,
the DFT level calculation for N-doped LuH3 is acceptable. FIG. 1. (a) Ternary phase diagram (convex hull) of the Lu–N–H system at 1 GPa. The values of the enthalpy from the convex hull are shown next to the colored
circles. The circles with black solid boundaries denote the stable phases. II. COMPUTATIONAL DETAILS (b)
Comparison of the XRD pattern from reported experimental data22 (lower black
curve) and the pattern calculated for P3m1-Lu2H2N at ambient pressure (upper
red curve). The inset shows the crystal structure of P3m1-Lu2H2N, with green,
gray, and pink spheres depicting Lu, N, and H atoms, respectively. FIG. 1. (a) Ternary phase diagram (convex hull) of the Lu–N–H system at 1 GPa. The values of the enthalpy from the convex hull are shown next to the colored
circles. The circles with black solid boundaries denote the stable phases. (b)
Comparison of the XRD pattern from reported experimental data22 (lower black
curve) and the pattern calculated for P3m1-Lu2H2N at ambient pressure (upper
red curve). The inset shows the crystal structure of P3m1-Lu2H2N, with green,
gray, and pink spheres depicting Lu, N, and H atoms, respectively. 8, 038402-2 Matter Radiat. Extremes 8, 038402 (2023); doi: 10.1063/5.0151844
© Author(s) 2023 8, 038402-2 Matter and
Radiation at Extremes
RESEARCH ARTICLE
scitation.org/journal/mre
FIG. 2. (a) Crystal structure of Fm3m-
LuH3 with different types of H occupancy
sites. Green spheres depict Lu atoms;
pink and red spheres depict H occu-
pancy of O and T sites, respectively. (b)–(d) Calculated enthalpy of formation
of Lu4HmN12−m as a function of T-site
occupancy at 1, 10, and 50 GPa, respec-
tively. n(T) is the number of nitrogen
atoms in each stoichiometry occupying T
sites. FIG. 3. (a) Phonon spectra, Eliashberg phonon spectral function α2F(ω), and electron–phonon integral λ for R3m-Lu2H5N at 50 GPa. The magnitudes of the phonon
linewidths are represented by the sizes of the blue circles. (b) and (c) Crystal structures of R3m-Lu2H5N in the framework of Fm3m-LuH3 and the conventional cell,
respectively. Green, gray, and pink spheres depict Lu, N, and H atoms, respectively. Matter and
Radiation at Extremes RESEARCH ARTICLE scitation.org/journal/mre FIG. 2. (a) Crystal structure of Fm3m-
LuH3 with different types of H occupancy
sites. Green spheres depict Lu atoms;
pink and red spheres depict H occu-
pancy of O and T sites, respectively. (b)–(d) Calculated enthalpy of formation
of Lu4HmN12−m as a function of T-site
occupancy at 1, 10, and 50 GPa, respec-
tively. n(T) is the number of nitrogen
atoms in each stoichiometry occupying T
sites. FIG. 2. (a) Crystal structure of Fm3m-
LuH3 with different types of H occupancy
sites. Green spheres depict Lu atoms;
pink and red spheres depict H occu-
pancy of O and T sites, respectively. II. COMPUTATIONAL DETAILS (b)–(d) Calculated enthalpy of formation
of Lu4HmN12−m as a function of T-site
occupancy at 1, 10, and 50 GPa, respec-
tively. n(T) is the number of nitrogen
atoms in each stoichiometry occupying T
sites. FIG. 2. (a) Crystal structure of Fm3m-
LuH3 with different types of H occupancy
sites. Green spheres depict Lu atoms;
pink and red spheres depict H occu-
pancy of O and T sites, respectively. (b)–(d) Calculated enthalpy of formation
of Lu4HmN12−m as a function of T-site
occupancy at 1, 10, and 50 GPa, respec-
tively. n(T) is the number of nitrogen
atoms in each stoichiometry occupying T
sites. FIG. 2. (a) Crystal structure of Fm3m-
LuH3 with different types of H occupancy
sites. Green spheres depict Lu atoms;
pink and red spheres depict H occu-
pancy of O and T sites, respectively. (b)–(d) Calculated enthalpy of formation
of Lu4HmN12−m as a function of T-site
occupancy at 1, 10, and 50 GPa, respec-
tively. n(T) is the number of nitrogen
atoms in each stoichiometry occupying T
sites. 24 October 2024 05:16:26 FIG. 3. (a) Phonon spectra, Eliashberg phonon spectral function α2F(ω), and electron–phonon integral λ for R3m-Lu2H5N at 50 GPa. The magnitudes of the phon
inewidths are represented by the sizes of the blue circles (b) and (c) Crystal structures of R3m-Lu2H5N in the framework of Fm3m-LuH3 and the conventional c FIG. 3. (a) Phonon spectra, Eliashberg phonon spectral function α2F(ω), and electron–phonon integral λ for R3m-Lu2H5N at 50 GPa. The magnitudes of the phonon
linewidths are represented by the sizes of the blue circles. (b) and (c) Crystal structures of R3m-Lu2H5N in the framework of Fm3m-LuH3 and the conventional cell,
respectively. Green, gray, and pink spheres depict Lu, N, and H atoms, respectively. 8, 038402-3 Matter Radiat. Extremes 8, 038402 (2023); doi: 10.1063/5.0151844
© Author(s) 2023 Matter and
Radiation at Extremes RESEARCH ARTICLE RESEARCH ARTICLE scitation.org/journal/mre FIG. 4. (a) Dependence of minimum dynamically stable pressure on N-doping
concentration. (b) Dependence of Tc on N-doping concentration at 50 GPa. The
Coulomb pseudopotential uses μ∗= 0.10. synthesized materials are metastable.40,41 Therefore, we calculated
the x-ray diffraction (XRD) pattern for this metastable compound. Figure 1(b) shows a comparison of experimental and calculated XRD
patterns. The calculated XRD pattern of P3m1-Lu2H2N deviates
clearly from the experimental one,22 indicating that this compound
does not occur in high-pressure experiments on N-doped lutetium
hydride superconductors. 24 October 2024 05:16:26 We then calculated the phonon spectra and superconduct-
ing properties of Lu4HmN12−m. Tc values were estimated using the
A-D-M equation with correction factors (Table S2, supplementary
material). At 1 and 10 GPa, Lu4HmN12−m cannot dynamically sta-
bilize, which may be due to the thermodynamical42 and dynamical
instability of the parent Fm3m-LuH3 [see Fig. S2(b), supplementary
material]. At 50 GPa, only R3m-Lu2H5N can dynamically stabilize. The crystal structure, phonon spectrum, and EPC of R3m-Lu2H5N
are illustrated in Fig. 3. R3m-Lu2H5N (Lu4H10N2) can be regarded
as Fm3m-LuH3 with two nitrogen atoms substituting its T and O
sites, respectively. The calculated phonon spectrum and EPC show
that the contributions of medium- and low-frequency phonons
(13–25 THz) to the EPC are the highest (about 46% to total λ),
whereas high-frequency phonons (45–55 THz) make hardly any
contribution. Thus, the EPC of R3m-Lu2H5N is primarily con-
tributed by medium- and low-frequency phonons. The calculated
EPC parameter λ for R3m-Lu2H5N at 50 GPa in the harmonic
approximation is 0.82. Using the calculated logarithmic average fre-
quency ωlog, along with a Coulomb pseudopotential μ∗value of 0.1,
the resultant Tc value is 27 K. FIG. 4. (a) Dependence of minimum dynamically stable pressure on N-doping
concentration. (b) Dependence of Tc on N-doping concentration at 50 GPa. The
Coulomb pseudopotential uses μ∗= 0.10. with correction factors and a Coulomb pseudopotential35 with
μ∗= 0.10 or 0.13. II. COMPUTATIONAL DETAILS Next, we investigated the doping effect on N-doped LuH3
using the supercell method. The cubic cell of Lu4HmN12−m was
constructed by replacing hydrogen atoms with nitrogen atoms, for
m = 8–11. For each concentration, we performed a geometry opti-
mization on the configurations of various octahedral (O) and tetra-
hedral (T) sites [see Fig. 2(a)] and then calculated the total energy. Figures 2(b)–2(d) show the results for the formation enthalpy of
Lu4HmN12−m at different pressures. At 1 GPa, only the formation
enthalpy of Lu4H11N is negative (∼−24 meV/atom), indicating that
this compound may be more stable than the others. A similar sit-
uation also occurs at 10 GPa (where the formation enthalpy is
∼−32 meV/atom for Lu4H11N). Thus, only Lu4H11N is thermo-
dynamically encouraged to be formed below 10 GPa. At 50 GPa,
Lu4H11N, Lu2H5N, Lu4H9N3, and LuH2N are thermodynamically
encouraged to be formed. Thus, Lu4HmN12−m with low nitrogen
doping is enthalpically favored at low pressure. The doping con-
centration of nitrogen increases with increasing pressure. In addi-
tion, when one nitrogen atom occupies a T site, the formation
enthalpy of Lu4HmN12−m at 50 GPa is the lowest. Therefore, one
nitrogen atom occupying a T site in Lu4HmN12−m is enthalpically
preferred. III. RESULTS AND DISCUSSION We performed a random structure search in the Lu–N–H sys-
tem and constructed the ternary phase diagram (convex hull) at
1 GPa [Fig. 1(a)]. Some of the binary compounds were adopted from
previous papers.36–39 Notably, all predicted potential ternary com-
pounds lie above the convex hull at 1 GPa. Thus, no ternary Lu–N–H
compounds can remain thermodynamically stable at this pressure,
which is consistent with the main results of Xie et al.26 In addi-
tion, P3m1-Lu2H2N was found with an enthalpy of ∼3 meV/atom
above the convex hull. Detailed information about the structural
parameters is listed in Table S1 (supplementary material). According
to the inorganic crystal structure database, 20% of experimentally In the case of low nitrogen doping concentrations, we used
the VCA method to investigate the pressure dependence of Tc in
N-doped Fm3m-LuH3. Figure 4(a) shows the dependence of the
minimum dynamically stable pressure on the N-doping concen-
tration. We find that the minimum dynamically stable pressure of
N-doped Fm3m-LuH3 increases from 25 to 70 GPa when the dop-
ing concentration increases from 0% to 2%. Thus, doping with N
atoms will raise the dynamically stable pressure of LuH3. Through
a softening mechanism,43 pressure can affect Tc by altering the
electron–phonon constant λ. Therefore, we calculated the Tc of 8, 038402-4 Matter Radiat. Extremes 8, 038402 (2023); doi: 10.1063/5.0151844
© Author(s) 2023 RESEARCH ARTICLE scitation.org/journal/mre FIG. 5. (a) Electronic band structure and DOS (states eV−1 f.u.−1) of LuH3 (solid black curves) and LuH2.97N0.03 (solid red curves) at 50 GPa. The grey solid horizontal line
ndicates the Fermi energy. (b) and (c) Phonon spectra, Eliashberg phonon spectral function α2F(ω), and electron–phonon integral λ for LuH3 and LuH2.97N0.03, respectively,
at 50 GPa. The magnitudes of the phonon linewidths are represented by the sizes of the blue circles. 24 October 2024 05:16:26 FIG. 5. (a) Electronic band structure and DOS (states eV−1 f.u.−1) of LuH3 (solid black curves) and LuH2.97N0.03 (solid red curves) at 50 GPa. The grey solid horizontal line
indicates the Fermi energy. (b) and (c) Phonon spectra, Eliashberg phonon spectral function α2F(ω), and electron–phonon integral λ for LuH3 and LuH2.97N0.03, respectively,
at 50 GPa. The magnitudes of the phonon linewidths are represented by the sizes of the blue circles. 24 October 2024 05:16:26 FIG. 5. (a) Electronic band structure and DOS (states eV−1 f.u.−1) of LuH3 (solid black curves) and LuH2.97N0.03 (solid red curves) at 50 GPa. REFERENCES 1C. J. Pickard, I. Errea, and M. I. Eremets, “Superconducting hydrides under
pressure,” Annu. Rev. Condens. Matter Phys. 11, 57 (2020). 2D. Duan, Y. Liu, Y. Ma, Z. Shao, B. Liu, and T. Cui, “Structure and
superconductivity of hydrides at high pressures,” Natl. Sci. Rev. 4, 121 (2017). 24 October 2024 05:16:26 3X. Zhang, Y. Zhao, F. Li, and G. Yang, “Pressure-induced hydride superconduc-
tors above 200 K,” Matter Radiat. Extremes 6, 068201 (2021). 4 4H.-K. Mao, “Hydrogen and related matter in the pressure dimension,” Matter
Radiat. Extremes 7, 063001 (2022). 5D. Duan, Y. Liu, F. Tian, D. Li, X. Huang, Z. Zhao, H. Yu, B. Liu, W. Tian,
and T. Cui, “Pressure-induced metallization of dense (H2S)2H2 with high-Tc
superconductivity,” Sci. Rep. 4, 6968 (2014). 6A. P. Drozdov, M. I. Eremets, I. A. Troyan, V. Ksenofontov, and S. I. Shylin,
“Conventional superconductivity at 203 kelvin at high pressures in the sulfur
hydride system,” Nature 525, 73 (2015). 7M. Einaga, M. Sakata, T. Ishikawa, K. Shimizu, M. I. Eremets, A. P. Drozdov, I. A. Troyan, N. Hirao, and Y. Ohishi, “Crystal structure of the superconducting phase
of sulfur hydride,” Nat. Phys. 12, 835 (2016). III. RESULTS AND DISCUSSION The grey solid horizontal line
indicates the Fermi energy. (b) and (c) Phonon spectra, Eliashberg phonon spectral function α2F(ω), and electron–phonon integral λ for LuH3 and LuH2.97N0.03, respectively,
at 50 GPa. The magnitudes of the phonon linewidths are represented by the sizes of the blue circles. We calculated the band structure and density of states (DOS)
of LuH3 and LuH2.97N0.03 (1% N-doped) at 50 GPa [Fig. 5(a)]. The
finite DOS at the Fermi level indicates the metallic nature of these
structures. LuH3 has a DOS N(ϵF) that reaches 0.269 states eV−1
f.u.−1 at the Fermi level. Doping N atoms into LuH3 will raise the
Fermi level and cause the bands near the Γ point to fall on top of the
Fermi level. Consequently, the Fermi level can be moved closer to
the DOS peak, and N(ϵF) will then increase to 0.6 states eV−1 f.u.−1
Therefore, doping by N atoms can significantly enhance the metallic
characteristic of LuH3 by moving the Fermi level closer to the DOS
peak. N-doped LuH3 with doping concentrations ranging from 0% to 1.5%
at 50 GPa [see Fig. 4(b)] to investigate the effects of doping with
nitrogen atoms on superconductivity. Our simulations show that the
lowest Tc is 4 K for LuH3 without doping. In addition, Tc increases
with increasing N-doping concentration; thus, doping N atoms
into LuH3 will increase Tc. However, the highest Tc in this VCA
calculation is 22 K, obtained with 1% N-doping at 30 GPa (see
Table S2, supplementary material), which is much lower than
room temperature. Notably, the anharmonicity correction to the
atomic motions imposed by the large ionic quantum fluctuation will
renormalize the phonon frequency in hydrogen-based superconduc-
tors. Therefore, the anharmonic effect may potentially decrease the
dynamically stable pressure of N-doped LuH3 and affect Tc, which
requires further theoretical investigation in this system. We then examined the phonon spectra and EPC of LuH3
and LuH2.97N0.03 at 50 GPa [Figs. 5(b) and 5(c)]. In LuH3, the
electron–phonon constant λ is primarily contributed by the optical Matter Radiat. Extremes 8, 038402 (2023); doi: 10.1063/5.0151844
© Author(s) 2023 8, 038402-5 8, 038402-5 Matter and
Radiation at Extremes Matter and
Radiation at Extremes RESEARCH ARTICLE scitation.org/journal/mre SUPPLEMENTARY MATERIAL 8F. Peng, Y. Sun, C. J. Pickard, R. J. Needs, Q. Wu, and Y. Ma, “Hydrogen
clathrate structures in rare earth hydrides at high pressures: Possible route to
room-temperature superconductivity,” Phys. Rev. Lett. 119, 107001 (2017). See the supplementary material for supplementary figures and
tables. 9H. Liu, I. I. Naumov, R. Hoffmann, N. W. Ashcroft, and R. J. Hemley, “Potential
high-Tc superconducting lanthanum and yttrium hydrides at high pressure,” Proc. Natl. Acad. Sci. U. S. A. 114, 6990 (2017). Author Contributions branch (λopt), which accounts for ∼69% of the total λ. Conversely,
the acoustic branch (λac) makes a much smaller contribution to
λ, accounting for ∼31% of the total λ. Doping by nitrogen atoms
at 1% concentration increases λac from 0.137 to 0.268, while λopt
remains almost unchanged. Therefore, the increased Tc of N-doped
LuH3 can be attributed to the enhancement of λac. Interestingly,
the optical branch with a frequency of ∼21 THz along the W–L–Γ
direction in LuH3 varies slightly with the wave vector q in the Bril-
louin zone. However, a significant softening of this phonon mode
is observed after doping by nitrogen atoms [Fig. 5(c)]. When the
pressure decreases to 25 GPa (Fig. S4, supplementary material),
the imaginary phonon frequency occurs near the L point, which
indicates that the optical branch softening induced by N doping is
responsible for the reduced stability of LuH3. Zihao Huo: Conceptualization (equal); Data curation (equal); For-
mal analysis (equal); Writing – original draft (equal); Writing –
review & editing (equal). Defang Duan: Conceptualization (lead);
Formal analysis (lead); Funding acquisition (lead); Investigation
(lead); Supervision (lead); Writing – review & editing (lead). Tiancheng Ma: Data curation (equal); Methodology (equal). Zihan
Zhang: Conceptualization (supporting); Writing – review & editing
(supporting). Qiwen Jiang: Writing – review & editing (supporting). Decheng An: Data curation (supporting). Hao Song: Conceptual-
ization (supporting). Fubo Tian: Methodology (supporting). Tian
Cui: Conceptualization (lead); Funding acquisition (lead); Method-
ology (equal); Supervision (equal); Writing – review & editing
(equal). DATA AVAILABILITY We performed a first-principles study on the Lu–N–H sys-
tem and found no stable ternary compounds at 1 GPa. We then
analyzed N-doped Fm3m-LuH3 using supercell and VCA meth-
ods. The result of the supercell method indicates that R3m-Lu2H5N
can be dynamically stable at 50 GPa, with a Tc of 27 K. The
VCA results indicate that the highest Tc is 22 K, obtained with 1%
N-doping at 30 GPa. In addition, doping with nitrogen atoms
slightly increases the Tc of Fm3m-LuH3 by enhancing the EPC of
acoustic phonons. However, this doping effect also leads to signifi-
cant phonon softening and increases the dynamically stable pressure
of LuH3. Finally, within the pressure range investigated in our study,
the highest Tc of N-doped Fm3m-LuH3 does not exceed 30 K, which
is much lower than room temperature. Our theoretical calcula-
tions were performed using standard DFT parameters and assuming
conventional superconductivity, and calculations considering more
corrections, including strong electron correlations, spin–orbit cou-
pling, the anharmonicity effect, and unconventional mechanisms of
superconductivity are required in the future. The data that support the findings of this study are avail-
able within the article and its supplemental material and from the
corresponding authors upon reasonable request. ACKNOWLEDGMENTS This work was supported by the National Key R&D Program
of China (Grant Nos. 2018YFA0305900 and 2022YFA1402304),
the National Natural Science Foundation of China (Grant Nos. 12122405, 52072188, and 12274169), the Program for Changjiang
Scholars and Innovative Research Team in University (Grant No. IRT_15R23), and a Jilin Provincial Science and Technology Devel-
opment Project (Grant No. 20210509038RQ). Some of the calcula-
tions were performed at the High Performance Computing Center of
Jilin University and on TianHe-1(A) at the National Supercomputer
Center in Tianjin. 10A. P. Drozdov, P. P. Kong, V. S. Minkov, S. P. Besedin, M. A. Kuzovnikov,
S. Mozaffari, L. Balicas, F. F. Balakirev, D. E. Graf, V. B. Prakapenka, E. Green-
berg, D. A. Knyazev, M. Tkacz, and M. I. Eremets, “Superconductivity at 250 K in
lanthanum hydride under high pressures,” Nature 569, 528 (2019). 11M. Somayazulu, M. Ahart, A. K. Mishra, Z. M. Geballe, M. Baldini, Y. Meng,
V. V. Struzhkin, and R. J. Hemley, “Evidence for superconductivity above 260 K
in lanthanum superhydride at megabar pressures,” Phys. Rev. Lett. 122, 027001
(2019). 12X. Li, X. Huang, D. Duan, C. J. Pickard, D. Zhou, H. Xie, Q. Zhuang, Y. Huang,
Q. Zhou, B. Liu, and T. Cui, “Polyhydride CeH9 with an atomic-like hydrogen
clathrate structure,” Nat. Commun. 10, 3461 (2019). 13F. Hong, L. Yang, P. Shan, P. Yang, Z. Liu, J. Sun, Y. Yin, X. Yu, J. Cheng, and
Z. Zhao, “Superconductivity of lanthanum superhydride investigated using the
standard four-probe configuration under high pressures,” Chin. Phys. Lett. 37,
107401 (2020). Conflict of Interest Chiarotti, M. Cococcioni, I. Dabo et al., “QUANTUM ESPRESSO: A modular and open-source software project for quantum simulations of
materials,” J. Phys.: Condens. Matter 21, 395502 (2009). 18M. Du, H. Song, Z. Zhang, D. Duan, and T. Cui, “Room-temperature supercon-
ductivity in Yb/Lu substituted clathrate hexahydrides under moderate pressure,”
Research 2022, 9784309. 34P. B. Allen and R. C. Dynes, “Transition temperature of strong-coupled
superconductors reanalyzed,” Phys. Rev. B 12, 905 (1975). 19H. Song, Z. Zhang, T. Cui, C. J. Pickard, V. Z. Kresin, and D. Duan, “High
Tc superconductivity in heavy rare earth hydrides,” Chin. Phys. Lett. 38, 107401
(2021). 35P. Morel and P. W. Anderson, “Calculation of the superconducting state
parameters with retarded electron-phonon interaction,” Phys. Rev. 125, 1263
(1962). 20M. Shao, S. Chen, W. Chen, K. Zhang, X. Huang, and T. Cui, “Superconducting
ScH3 and LuH3 at megabar pressures,” Inorg. Chem. 60, 15330 (2021). 36J. E. Bonnet and J. N. Daou, “Rare-earth dihydride compounds: Lattice thermal
expansion and investigation of the thermal dissociation,” J. Appl. Phys. 48, 964
(1977). 21Z. Li, X. He, C. Zhang, K. Lu, B. Bin, J. Zhang, S. Zhang, J. Zhao, L. Shi, S. Feng, X. Wang, Y. Peng, R. Yu, L. Wang, Y. Li, J. Bass, V. Prakapenka, S. Chariton,
H. Liu, and C. Jin, “Superconductivity above 70 K experimentally discovered in
lutetium polyhydride,” Sci. China Phys. Mech 66, 267411 (2023). 37M. Mansmann and W. E. Wallace, “The structure of HoD3,” J. Phys. France 25,
454 (1964). 38W. Klemm and G. Winkelmann, “Zur kenntnis der nitride der seltenen
erdmetalle,” Z. Anorg. Allg. Chem. 288, 87 (1956). 39 22N. Dasenbrock-Gammon, E. Snider, R. McBride, H. Pasan, D. Durkee, N. Khalvashi-Sutter, S. Munasinghe, S. E. Dissanayake, K. V. Lawler, A. Salamat, and
R. P. Dias, “Evidence of near-ambient superconductivity in a N-doped lutetium
hydride,” Nature 615, 244 (2023). 39R. Boese, N. Niederprüm, D. Bläser, A. Maulitz, M. Y. Antipin, and P. R. Mallinson, “Single-crystal structure and electron density distribution of ammo-
nia at 160 K on the basis of X-ray diffraction data,” J. Phys. Chem. B 101, 5794
(1997). 24 October 2024 05:16:26 23P. Shan, N. Wang, X. Zheng, Q. Qiu, Y. Peng, and J. Cheng, “Pressure-induced
color change in the lutetium dihydride LuH2,” Chin. Phys. Lett. 40, 046101 (2023). 24 40Y. Hinuma, T. Hatakeyama, Y. Kumagai, L. A. Burton, H. Sato, Y. Muraba, S. Iimura, H. Hiramatsu, I. Tanaka, H. Hosono, and F. Conflict of Interest 14H. Xie, Y. Yao, X. Feng, D. Duan, H. Song, Z. Zhang, S. Jiang, S. A. T. Redfern,
V. Z. Kresin, C. J. Pickard, and T. Cui, “Hydrogen pentagraphenelike structure The authors have no conflicts to disclose. 8, 038402-6 Matter Radiat. Extremes 8, 038402 (2023); doi: 10.1063/5.0151844
© Author(s) 2023 8, 038402-6 © Author(s) 2023 Matter and
Radiation at Extremes RESEARCH ARTICLE RESEARCH ARTICLE scitation.org/journal/mre 28M. D. Segall, P. J. D. Lindan, M. J. Probert, C. J. Pickard, P. J. Hasnip, S. J. Clark,
and M. C. Payne, “First-principles simulation: Ideas, illustrations and the CASTEP
code,” J. Phys.: Condens. Matter 14, 2717 (2002). stabilized by hafnium: A high-temperature conventional superconductor,” Phys. Rev. Lett. 125, 217001 (2020). 15P. Kong, V. S. Minkov, M. A. Kuzovnikov, A. P. Drozdov, S. P. Besedin,
S. Mozaffari, L. Balicas, F. F. Balakirev, V. B. Prakapenka, S. Chariton, D. A. 29P. E. Blöchl, “Projector augmented-wave method,” Phys. Rev. B 50, 17953
(1994). Knyazev, E. Greenberg, and M. I. Eremets, “Superconductivity up to 243 K in the
yttrium-hydrogen system under high pressure,” Nat. Commun. 12, 5075 (2021). 30G. Kresse and D. Joubert, “From ultrasoft pseudopotentials to the projector
augmented-wave method,” Phys. Rev. B 59, 1758 (1999).i 16Z. Zhang, T. Cui, M. J. Hutcheon, A. M. Shipley, H. Song, M. Du, V. Z. Kresin,
D. Duan, C. J. Pickard, and Y. Yao, “Design principles for high-temperature super- 16Z. Zhang, T. Cui, M. J. Hutcheon, A. M. Shipley, H. Song, M. Du, V. Z. Kresin,
D. Duan, C. J. Pickard, and Y. Yao, “Design principles for high-temperature super-
conductors with a hydrogen-based alloy backbone at moderate pressure,” Phys. Rev. Lett. 128, 047001 (2022). 31G. Kresse and J. Furthmüller, “Efficiency of ab-initio total energy calculations
for metals and semiconductors using a plane-wave basis set,” Comput. Mater. Sci. 6, 15 (1996). conductors with a hydrogen-based alloy backbone at moderate pressure,” Phys. Rev. Lett. 128, 047001 (2022). 32J. P. Perdew, K. Burke, and M. Ernzerhof, “Generalized gradient approximation
made simple,” Phys. Rev. Lett. 77, 3865 (1996). 17L. Ma, K. Wang, Y. Xie, X. Yang, Y. Wang, M. Zhou, H. Liu, X. Yu, Y. Zhao, H. Wang, G. Liu, and Y. Ma, “High-temperature superconducting phase in clathrate
calcium hydride CaH6 up to 215 K at a pressure of 172 GPa,” Phys. Rev. Lett. 128,
167001 (2022). 33P. Giannozzi, S. Baroni, N. Bonini, M. Calandra, R. Car, C. Cavazzoni, D. Ceresoli, G. L. Matter Radiat. Extremes 8, 038402 (2023); doi: 10.1063/5.0151844
© Author(s) 2023 Conflict of Interest Oba, “Discovery of earth-
abundant nitride semiconductors by computational screening and high-pressure
synthesis,” Nat. Commun. 7, 11962 (2016). 24X. Ming, Y.-J. Zhang, X. Zhu, Q. Li, C. He, Y. Liu, B. Zheng, H. Yang,
and H.-H. Wen, “Absence of near-ambient superconductivity in LuH2±xNy,”
arXiv:2303.08759 (2023). 24X. Ming, Y.-J. Zhang, X. Zhu, Q. Li, C. He, Y. Liu, B. Zheng, H. Yang,
d
“ b
f
b
d
” and H.-H. Wen, “Absence of near-ambient superconductivity in LuH2±xNy,”
arXiv:2303.08759 (2023). 41Y. Wu, P. Lazic, G. Hautier, K. Persson, and G. Ceder, “First principles high
throughput screening of oxynitrides for water-splitting photocatalysts,” Energy
Environ. Sci. 6, 157 (2013). 25M. Liu, X. Liu, J. Li, J. Liu, Y. Sun, X.-Q. Chen, and P. Liu, “On parent
structures of near-ambient nitrogen-doped lutetium hydride superconductor,”
arXiv:2303.06554 (2023). 42T. Palasyuk and M. Tkacz, “Pressure-induced structural phase transition in rare-
earth trihydrides. Part I. (GdH3, HoH3, LuH3),” Solid State Commun. 133, 481
(2005). 26F. Xie, T. Lu, Z. Yu, Y. Wang, Z. Wang, S. Meng, and M. Liu, “Lu-H-N phase
diagram from first-principles calculations,” Chin. Phys. Lett 40, 057401 (2023) . 43W. L. McMillan, “Transition temperature of strong-coupled superconductors,”
Phys. Rev. 167, 331 (1968). 27C. J. Pickard and R. J. Needs, “Ab initio random structure searching,” J. Phys.:
Condens. Matter 23, 053201 (2011). 8, 038402-7 8, 038402-7
|
https://openalex.org/W4311456830
|
https://journalofbigdata.springeropen.com/counter/pdf/10.1186/s40537-022-00672-6
|
English
| null |
Enabling real time big data solutions for manufacturing at scale
|
Journal of big data
| 2,022
|
cc-by
| 12,201
|
© The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits
use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original
author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third
party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the mate-
rial. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or
exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://
creativecommons.org/licenses/by/4.0/. CASE STUDY Open Access Abstract Today we create and collect more data than we have in the past. All this data comes
from different sources, including social media platforms, our phones and computers,
healthcare gadgets and wearable technology, scientific instruments, financial institu-
tions, the manufacturing industry, news channels, and more. When these data are
analyzed in a real-time nature, it offers businesses the opportunity to take quick action
in business-development processes (B2B, B2C), gain a different perspective, and better
understand applications, creating new opportunities. While changing their sales and
marketing strategies, businesses are now able to manage the data they collect in real-
time to transform themselves, to record them in a healthy way, to analyze and evalu-
ate data-based processes, and to determine their digital transformation roadmaps,
their interactions with their customers, sectoral diffraction, application, and analysis. They want to accelerate the transformation processes within the technology triangle. Thus, big data, recently called as small and wide data, is at the center of everything
and becomes an important application for digital transformation. Digital transforma-
tion helps companies embrace change and stay competitive in an increasingly digital
world. The value of big data in manufacturing, independent from sectoral variations,
comes from its ability to combine both in an organization’s efforts to both digitize
and automate its end-to-end business operations. In this study, the current digitaliza-
tion and automation applications of one of the plastic injection-based manufacturing
companies at scale will be discussed. Presented open-source-based big data analytics
platform, DataCone, that increases data processing efficiency, storage optimization,
encourages innovation for real time monitorization and analytics, and support new
business models in different industry segments will be demonstrated and discussed. Thus, development and applied ML solutions will be discussed providing important
prospects for the future. 2 Department of Physics
Engineering, Faculty of Science
and Letters, Istanbul Technical
University, Istanbul, Turkey
3 Parton Big Data Analytics
and Consulting, ITU Teknokent,
Sarıyer, Istabul, Turkey
4 Big Data and Business Analytics,
Department of Data Engineering
and Business Analytics, Istanbul
Technical University, Istanbul,
Turkey Keywords: Big data, Digital transformation, Real-time learning, Machine learning,
Manufacturing, Open source, Plastics injection Altan Cakir1,2,3,4*, Özgün Akın3,4, Halil Faruk Deniz3,4 and Ali Yılmaz4 Altan Cakir1,2,3,4*, Özgün Akın3,4, Halil Faruk Deniz3,4 and Ali Yılmaz4 *Correspondence:
altan.cakir@itu.edu.tr
1 Istanbul Technical University
Artificial Intelligence,
Data Science Research
and Application Center, Istanbul
Technical University, Istanbul,
Turkey
2 Department of Physics
Engineering, Faculty of Science
and Letters, Istanbul Technical
University, Istanbul, Turkey
3 Parton Big Data Analytics
and Consulting, ITU Teknokent,
Sarıyer, Istabul, Turkey
4 Big Data and Business Analytics,
Department of Data Engineering
and Business Analytics, Istanbul
Technical University, Istanbul,
Turkey *Correspondence:
altan.cakir@itu.edu.tr
1 Istanbul Technical University
Artificial Intelligence,
Data Science Research
and Application Center, Istanbul
Technical University, Istanbul,
Turkey
2 Department of Physics
Engineering, Faculty of Science
and Letters, Istanbul Technical
University, Istanbul, Turkey
3 Parton Big Data Analytics
and Consulting, ITU Teknokent,
Sarıyer, Istabul, Turkey
4 Big Data and Business Analytics,
Department of Data Engineering
and Business Analytics, Istanbul
Technical University, Istanbul,
Turkey Cakir et al. Journal of Big Data (2022) 9:118
https://doi.org/10.1186/s40537-022-00672-6 Cakir et al. Journal of Big Data (2022) 9:118
https://doi.org/10.1186/s40537-022-00672-6 Journal of Big Data *Correspondence:
altan.cakir@itu.edu.tr
1 Istanbul Technical University
Artificial Intelligence,
Data Science Research
and Application Center, Istanbul
Technical University, Istanbul,
Turkey
2 Department of Physics
Engineering, Faculty of Science
and Letters, Istanbul Technical
University, Istanbul, Turkey
3 Parton Big Data Analytics
and Consulting, ITU Teknokent,
Sarıyer, Istabul, Turkey
4 Big Data and Business Analytics,
Department of Data Engineering
and Business Analytics, Istanbul
Technical University, Istanbul,
Turkey Enabling real time big data solutions
for manufacturing at scale Altan Cakir1,2,3,4*, Özgün Akın3,4, Halil Faruk Deniz3,4 and Ali Yılmaz4 Introductionh The modern business world requires using the information as an important resource
in increasing competition. Organizational success can only be achieved by managing
information, transforming it into knowledge, and using the extracted knowledge. In
the digital transformation era, generating data-based strategies, data-driven business, Cakir et al. Journal of Big Data (2022) 9:118 Page 2 of 24 will provide optimizing the performance of the companies by collecting and analyzing
data through the product life cycle [1]. Processing data is not a new sight for companies. Companies have systems for stor-
ing and processing data in order to accelerate business processes. On the other hand,
most of them have traditional data warehouse technologies, which are not suitable
for extremely high-speed data from various sources [2], for the current data flow in
daily operations. IoT enables the enlargement of collectible data, big data technolo-
gies provide an opportunity for data to be processed and transformed into knowledge
at scale. Big Data is generally described as technology that enables to obtain informa-
tion from high-speed data from different sources by applying statistics, mathematics,
econometric, simulations, optimizations, and/or other techniques to support deci-
sion-making processes [3] in real-time. Therefore, big data technologies and deploy-
ment of a data lake are considered in companies now in addition to data warehouse
solutions. Managing all types of data, studying specific analytical studies by multiple
users, providing the required data lineage back to source systems, and enabling users
to access the analytical contents in a self-serve manner are the necessities of deploy-
ment of the data lake operations [4]. The manufacturing industry is one of the largest areas to create value from data. Smart manufacturing is the goal of companies in manufacturing. Smart manufac-
turing aims to convert data acquired across the product and process life cycle into
manufacturing intelligence to get positive effects on all areas of manufacturing [5]. Machines, sensors, and other equipment are the various data sources in manufactur-
ing that make essential big data. Data analysis can give meaning to patterns, trends,
areas of inefficiency, and potential risk to manufacturers to provide improvement of
process efficiencies [6]. Creating a real-time monitoring system provides accurate
and timely decision-making in operational processes. All of the reasons and possible
effects say it is expected that enabling big data solutions will contribute significantly
to the advancement of smart manufacturing [7]. Introductionh There are lots of areas that can gain points in manufacturing, on the other hand,
big data usage is lower than other industries such as social media, e-commerce, and
finance with respect to manufacturing due to software, middleware, and hardware
challenges. There are five fundamental main challenges in manufacturing data sourc-
ing and collection, data integrity, data processing, data storage and advanced data
analytics. In the data acquisition stage, different types, heterogeneous structures, and
various dimensions of data are the challenges that can be faced. In the data prepos-
sessing stage, integration of data, data cleaning and matching, data redundancy and
data compression are challenging tasks. In data storage, reliability of the database,
scalability, and efficiency are the issues. Data security, data privacy, the efficiency of
data mining, temporal and spatial correlation are the issues that can be encountered
[8]. In this article, the big data management and operational analyses from the plastic
injection processes of real applications are discussed. Infrastructure, components, and
architecture of big data platform are mentioned, problems encountered and their solu-
tions in implementation are explained. Time series integrated sequential machine learn-
ing and deep learning deployment are briefly presented. Cakir et al. Journal of Big Data (2022) 9:118 Page 3 of 24 Architecture design In this section, DataCone’s infrastructure and architecture are presented. Big data
components that are used in DataCone, are explained briefly. The details of the sys-
tem are discussed in the optional information section. Case description As companies move deeper into digital technologies, production forecasting meth-
odologies are more widely adopted, there are more opportunities than ever to trans-
form routine production runs with data-driven decision that makes a difference. This
is largely because of the maturation of big data—a prominent term for a solution of
storage, organization, and analysis techniques developed for massive data sets in the
context of various manufacturing processes. Our case study is a large scale common
manufacturing company that produces automobile plastic components using injec-
tion molding techniques. Although injection molding based large scale production is
considered a well-defined manufacturing technology, it requires to stay competitive
and adapt to the dynamic market demands. Therefore, many companies are willing to
move towards smart manufacturing processes, or Industry 4.0 applications [9]. Plastic
injection molding is a significantly important process and the quality of the produced
parts is mostly affected by the process conditions such as injection temperatures,
injection pressures, injection speeds, ambient temperatures. Optimum injection
parameters, environmental conditions, and other reasons that have effects on product
quality and machines operations are not specified exactly. Therefore, to go beyond
classical engineering studies, establishing a real time big data management system
is the first step to integrating data driven applications for operational gains. The Big
Data operation includes the generation, manipulation, ingestion, acquisition, storage,
processing, and analysis of data. During injection molding, a large scale of data is gen-
erated and can be successfully collected by sensor sets installed in different units of
the injection molding machine and other platforms. Although data is one of the most
prominent assets of an intelligent solutions, many applications have difficulties select-
ing essential and useful analytical solutions from the manufacturing processes effec-
tively. Therefore, many studies have been made to adopt machine learning (ML)
techniques — especially for injection molding operations — for industrial application. This is essential for artificial intelligence studies in order to analyze the data obtained
from production and environmental conditions in real-time nature [9]. Infrastructure DataCone’s big data cluster is built on 11 virtual machines which have different tech-
nical features. The machines in the cluster totally have 128 CPUs, 512 GB ram, and
40 TB SSD disk space. The distribution of the hardware fits the requirements of the
big data system tools to be installed and the amount of data to be processed at a
certain time. In this context, a namenode and a secondary namenode are used pri-
marily to ensure high availability in the Hadoop file system [10]. The task of the sec-
ondary namenode is to keep the replica of the system records and to ensure that the
system continues without interruption in case a problem occurs in the namenode. After HDFS and mapreduce configurations are made, YARN [11] and Spark [12] are Cakir et al. Journal of Big Data (2022) 9:118 Page 4 of 24 Fig. 1 Cluster design of DataCone with master node to manage the cluster, secondary master node to
ensure high availability, and 9 slave nodes. The infrastructure of DataCone is designed for manufacturing
companies considering data frequency, data volume, and sector-specific IoT protocols. Open-source big
data software is distributed over the nodes to optimize hardware cost. The main logic of the infrastructure
depends on scalable structure. When data volume is increased or new devices are needed to be added,
infrastructure will be easily scaled by adding new nodes Fig. 1 Cluster design of DataCone with master node to manage the cluster, secondary master node to
ensure high availability, and 9 slave nodes. The infrastructure of DataCone is designed for manufacturing
companies considering data frequency, data volume, and sector-specific IoT protocols. Open-source big
data software is distributed over the nodes to optimize hardware cost. The main logic of the infrastructure
depends on scalable structure. When data volume is increased or new devices are needed to be added,
infrastructure will be easily scaled by adding new nodes Fig. 2 Detailed architecture design of DataCone with a combination of proper open-source big data
software and enterprise software which are already used by the company. DataCone’s architecture
ensures seamless interaction between existing manufacturing management systems and novel big data
technologies. The data flows from left to right in this architecture. The data that is produced by IoT sensors
and PLCs is consumed by Kepware OPC Server and published to the cluster via proper protocols. Infrastructure Apache
Nifi consumes this data and enriches it by combining it with the data that is stored in ERP systems. After the
enrichment process, the data is pushed to the storage and analytics layers for further analysis Fig. 2 Detailed architecture design of DataCone with a combination of proper open-source big data
software and enterprise software which are already used by the company. DataCone’s architecture
ensures seamless interaction between existing manufacturing management systems and novel big data
technologies. The data flows from left to right in this architecture. The data that is produced by IoT sensors
and PLCs is consumed by Kepware OPC Server and published to the cluster via proper protocols. Apache
Nifi consumes this data and enriches it by combining it with the data that is stored in ERP systems. After the
enrichment process, the data is pushed to the storage and analytics layers for further analysis Cakir et al. Journal of Big Data (2022) 9:118 Page 5 of 24 installed on all nodes, which has active HDFS usage together with the in-memory
computing model. In this way, it is aimed to use the power of memory-based process-
ing, in contrast to disk-based processing in Hadoop technologies, in the entire cluster
via Apache Spark. Elasticsearch [13] is added to the big data system in order to store
data for a short time and run fast queries on the data for real-time query and report-
ing. All in all, considering data size and data flow frequency, Elasticsearch is installed
in the cluster as 3 datanode, 3 masternode and 2 client nodes. Furthermore, Apache
Nifi [14] is built on 3 nodes in cluster mode to set up streaming pipelines and define
data streams. Corresponding heterogenous components to be used in DataCone are
positioned in the cluster as shown in the Figs. 1, 2. Apache Nifi Nifi was formerly developed by the National Security Agent (NSA) and is based on
open source Niagara Files software as part of the technology transfer program in
2014. It is an open software for automating and monitoring network data movement
between heterogeneous systems. It can analyze different data formats and proto-
cols and operates on Java Virtual Machine [14]. NiFi implements the concept of FBP
(Flow-Based Programming) as a real-time ETL for collecting large amounts of data
in a distributed environment. Generally, ETL means to extract data from the same
model or other models to a data warehouse or data lake in our case, transform the
data to save the data in appropriate format or structure for inquiry or analysis [15]. In ETL or data in motion, the major concern that how to secure, track and manipulate
the data flow. Therefore, Apache NiFi, which is our data automation platform, is capable
of handling millions/billions of records to ingest and enrich data in near real-time in a
distributed environment. In addition, Apache NiFi has been utilized as a user-friendly
web UI with loT ready-use processors. Processors are doing some combination of data
routing, transformation, or mediation between systems by accessing the incoming flow
files and their contents. The Processor can also operate independently without the flow
files [16]. Apache NiFi supports dataflow management for both structured and unstruc-
tured data, powered by the separation of metadata and payload. Schema is not required
but can be used as optional [17]. In DataCone, Nifi is used as a data entry point of the big data platform. All the produc-
tion data is pulled using Apache Nifi from local servers and sensors. There are struc-
tured data and unstructured data which are coming from SQL Server and MQTT server. Also because of the constant change in the production area, the structure of data has
a constantly changing schema. Nifi was chosen to easily manage both structured and
unstructured data in a constantly changing production environments. Apache Kafka Kreps et al. (2011) introduced Apache Kafka, a distributed messaging system that is spe-
cially designed for a high volume of log events processing. It also provides integrated
distributed support and can scale-out. Kafka achieves much higher throughput than
conventional messaging systems (such as ActiveMQ and RabbitMQ) [18]. Cakir et al. Journal of Big Data (2022) 9:118 Cakir et al. Journal of Big Data (2022) 9:118 Page 6 of 24 Apache Kafka can be deployed on bare-metal hardware, virtual machines, and con-
tainers, and on-premises as well as in the cloud systems [19]. It consists of several
capabilities, therefore it can be implemented for end-to-end event streaming. These
capabilities are to publish (write) and subscribe to (read) streams of events including
continuous import/export of data from other systems, to store streams of events durably
and reliably, to process streams of events as they occur, or retrospectively. Apache Kafka is therefore placed right after the Apache Nifi in the DataCone pipeline. Near real-time production, data is subscribed to the Apache Kafka topics to be stored
temporarily and many systems commune data from these Kafka topics with low latency
and high security. Elasticsearch Elasticsearch is an open-source, real-time, and distributed search and analytics engine
based on the Lucene library, is released in February 2010 [20, 21]. It is used to store,
search and analyze big data with analytically created indices. Elasticsearch stores data as
JSON(Javascript Object Notation) documents, and retrieves whatever document with
fast query. It is generally used by big companies such as Netflix, Linkedin for web search,
log analysis, and big data analytics [22]. In order to understand the working principle of Elasticsearch, the terms index, shard,
node, replica, cluster should be briefly discussed. The index is similar to a database in a
relational fashion. Elasticsearch stores data in one or more indices and reads the data
from these indices. Each index must have a unique name and must be created in lower-
case letters. Every index is made up of one or more shards [13, 23]. In DataCone, production data is consumed to be indexed in Elasticsearch from Kafka
topics using NiFi processors. Thanks to Elasticsearch, the production data become easily
searchable. Data is stored in Elasticsearch for the indicated intervals in a hot phase. To
be able to visualize the data near real-time, Elasticsearch is integrated with the Kibana
dashboard. Apache Spark Spark was developed as a unified engine that can work at various workloads for the anal-
ysis of big data. Apache spark was adapted to industry and academia in a short time and
became one of the most popular projects of Apache Software Foundation [27]. Com-
pared to previous technologies, spark is much faster and has a much more compact
structure. For example, in the study on logistic regression, it was concluded that spark
operates 100 times faster than Hadoop map-reduce [28]. Since spark provides APIs in
many programming languages such as Python, Java, Scala, R, it makes complex distrib-
uted big data analysis operations easier. Spark provides many impressive high-level tools that can be used in cluster computing
such as spark SQL for running SQL queries on spark, MLlib to build machine learning
models, Spark Streaming to handle streaming data, GraphX for graph processing [28]. Having these libraries, which have separate very important functions, made spark a gen-
eral big data processing engine. These tools are developed and reproduced in each ver-
sion of spark to keep it up-to-date and functional. Spark Streaming is used to process and compress near real-time production data in
DataCone’s architecture. The data is consumed from Kafka topics using Spark Streaming
code which is written in python. This code is processed all production data and saves it
to the Hadoop distributed file system as a parquet file in a 10 minutes time interval. The
data size is decreased ninety-five percent thanks to using the Parquet data format. Ambari Big data platforms in general consist of many open-source software working synchro-
nously on a distributed architecture. Everyone knows that it is not easy to install and
maintain these open source components individually [24]. In other words, it is difficult
to keep these systems alive in the production environment and to follow compatibility
problems in the application. The former Hortonworks, the new Cloudera, data platform
was developed in 2011 by the Yahoo team responsible for the Hadoop Project develop-
ments. [25] This platform provides many facilities for installing and managing big data
systems over a single interface which is called Ambari. Thanks to Ambari, big data sys-
tem components can be installed effectively on the cluster and it is possible to monitor
the problems in the architecture with certain types of tracking algorithms. In DataCone, modified version Ambari is used to install and manage HDFS, MapRe-
duce, YARN, Spark, Zeppelin, Kafka, and Hive software’s in the context of Lambda
architecture [26]. The system is based on eleven nodes and a secondary master node
is added to ensure sustainability. A Hadoop file system, which can be accessed through
the Ambari interface, has been installed, allowing easy access to the folders stored in Cakir et al. Journal of Big Data (2022) 9:118 Page 7 of 24 HDFS. Thanks to the Ambari interface, upload and download operations can be per-
formed on the file system established. Necessary configurations of the specified software
were made through the interface. After the installation phase, the Ambari was also used
to monitor the system status, and information about the number of nodes, storage space,
network, and CPU usage, and memory usage were visualized via the system monitoring
dashboard. MongoDB MongoDB is the most popular NoSQL database that is open-source document-oriented
[31]. MongoDB was developed in C++. Because MongoDB is a document-oriented
database, the system can have several instances of the database. Storing data is flexible
with MongoDB because it uses a syntax similar to JSON called BSON(Binary JSON). This eases the change of data structures and documents. The document model deter-
mines keys and values in JSON-like application code, this makes more intelligible and
readable data. Indexing is important for databases, it matches queries efficiently without
scanning every document of a collection. MongoDB uses indexing to process enormous
data rapidly. MongoDB is a cross-platform, document-oriented database that provides,
high performance, high availability, and easy scalability [32]. As a part of DataCone’s architecture, APIs are used to feed data to mobile applications
and web dashboards. These APIs read the data from MongoDB. JSON documents are
written to Mongo via custom python codes and these documents are updated at speci-
fied intervals. MySQL SQL (Structured Query Language) is a relational database management standard for
accessing and manipulating databases. SQL is used for executing queries, retrieving
data, inserting, updating, and deleting records, etc. There are lots of RDBMS (Relational
Database Management System) for using SQL such as MS SQL Server, Oracle, IBM DB2,
MySQL, and Microsoft Access. MySQL is an open-source RDBMS. Traditional databases are not effective when using
and processing large volumes of data. On the other hand, when master data tables, rela-
tional entities, basic attributes are considered, SQL cannot be ignored with its easy-to-
design structure and high efficiency. Therefore, MySQL is an open-source and powerful
system that was selected to store master data and determine relationships between them. In DataCone’s architecture, MySQL is the place where the master data of the devices
are stored. There are tables that store the descriptive information and the DataCone
standardized naming of devices. Apache Hadoop Manufacturing data consists of structured, semi-structured, and unstructured data. The
high volume of data is stored in HDFS for batch analysis. Hadoop Distributed File Sys-
tem (HDFS) is one of the key elements in the Hadoop Framework and it is an open-
source implementation of the Google File System (GFS) for storing a vast amount of
data. HDFS is a large distributed file system designed to be deployed on low-cost hard-
ware [29] and provides high throughput with fault-tolerance. HDFS is widely used in
research for its open-source and advanced architecture. It primarily settles the massive
capacity issue and data consistency. HDFS stores the records as a series of blocks and as duplicated for fault tolerance. Data partitioning, processing, columnar formats, replication, and placement of data
blocks will increment the performance of Hadoop. The performant columnar format in
the Hadoop Ecosystem is Parquet which is an open-source file format. Apache Parquet
is designed for efficiency as well as the performant flat columnar storage format of data
compared to row-based files like CSV or TSV files [30]. ii
Hadoop is used as a long-term distributed data storage in DataCone. After the data
is processed with Spark, it is saved to Hadoop as a parquet file. Data are classified Cakir et al. Journal of Big Data (2022) 9:118 Page 8 of 24 according to date. The file system is designed in a layered structure. In the first layer, data
is kept on a daily basis, and in the next layers, files are grouped by month and year. Flask Flask is a micro-framework for Python with a small core and easy-to-extend philoso-
phy. Depends on the Jinja template engine and the Werkzeug WSGI toolkit. It has no
database abstraction layer, form validation, or any other components where pre-exist-
ing third-party libraries provide common functions. Flask supports extensions. Exten-
sions exist for object-relational mappers, form validation, upload handling, various open
authentication technologies, and more [36]. Flask aims to keep the core framework sim-
ple but highly expansible means it is compatible with all Python libraries. It includes
all the necessary features on its micro-framework like development server, debugger,
secure cookie management, RESTful API compliance that can save time and effort for
programmers. Flask is used for developing custom dashboards and API’s in DataCone. After data is
processed with python, it is visualized in custom dashboards which are developed using
HTML and javascript. Thanks to Flask, these dashboards can be easily managed by
Python. Operational information In this section, operational details are discussed for each framework that is used in
DataCone. Kibana Kibana is an open-source interactive visualization interface and analysis tool for data in
Elasticsearch. It is an Elastic plugin. Kibana offers the opportunity to visualize data with
different types of graphs such as maps, charts, bars, tables, pies etc. [22]. Kibana allows
real-time monitoring with the power of Elasticsearch. Users can create dashboards by
editing the generated graphics [34]. Kibana presents all created visualizations, analyzes,
and time series to the user with dashboards. It shows the whole picture to the user along
with the filters [34, 35]. i
Kibana is used for real-time visualizations in DataCone. Thanks to the seamless con-
nection between Elasticsearch and Kibana, the data which flows to the Elasticsearch are
easily visualized on Kibana. Apache Airflowl Apache Airflow is an Apache Software Foundation project, originally developed by
Airbnb and released in 2016. Apache Airflow is a python-based fast-running, easy-to-
integrate and customizable platform to programmatically author, schedule, and monitor
workflows as Directed Acyclic Graphs (DAGs) of tasks [33]. In this way, both graphically
observing and creating workflows create a facilitating effect for processes. At the same
time, the created tasks do not need to share resources with each other, so it is possi-
ble to run independently from each other. It supports the establishment of workable,
repeatable structures of workflow studies. The general architecture of Airflow is shown Cakir et al. Journal of Big Data (2022) 9:118 Page 9 of 24 below and Airflow comprises three main components which are webserver, scheduler,
and worker. Apache Airflow is used to manage code flows in DataCone’s architecture. Spark and
python codes are scheduled via Airflow. When the code gets an error, Airflow is sent
an e-mail to the code responsible. Therefore the problems can be solved in a short time
period. Euromap protocol EUROMAP 63 is a file-based communication protocol for data exchange between Injec-
tion Molding Machines(IMMs) and the central computers. It was created by EUROMAP
(Europe’s Association for Plastics and Rubber Machinery Manufacturers) founded in Cakir et al. Journal of Big Data (2022) 9:118 Page 10 of 24 Fig. 3 A sample of file transfer via Euromap 63, that is plastic injection molding machines specific protocol
written by Euromap Organization to establish a connection between the machines and the digital systems Fig. 3 A sample of file transfer via Euromap 63, that is plastic injection molding machines specific protocol
written by Euromap Organization to establish a connection between the machines and the digital systems 1964 [37]. EUROMAP provides technical recommendations and protocols for plastics
and rubber machinery manufacturers [38]. The protocols it creates are control, com-
munication, and data digitization protocols suitable for machines of many brands such
as Engel, Krauss Maffei. Euromap 63 is one of the data digitization protocols. With the
Euromap 63 plug-in, part process data, machine status data, machine health data, etc. makes it collectible by digitizing. The data that want to be collected from the plastic
injection machine is written in Euromap 63 standards into the text file created in the
local folder where the machine communicates in the central computer. Euromap 63
plug-in reads this file and retrieves the data from the machine and delivers the desired
data in the same folder as a text file. In this way, the data generated in the machine is col-
lected. The text files that the protocol reads and writes are shown in the Fig. 3. This is
the working logic of Euromap 63. It is possible to use the Euromap 77 version instead of
63 in some of the new injection molding machines. Euromap 77 is able to communicate
over OPC UA protocol. Real-time data can be moved to the big data systems directly
over OPC UA protocol without needing any OPC servers. Kepware Kepware OPC server software is installed in the local environment is used to query and
collect data from different PLCs, injection machines, and sensors. Devices that are con-
nected to the company network are registered in the OPC server via their IP addresses. Devices are registered to the system using Kepware’s manufacturing plug-in. During
the registration, attention is paid to selecting data connection protocols suitable for the
device. For example, while the Euromap63 protocol is selected for injection machines,
the Modbus TCP-IP protocol is selected to activate the connection of temperature and
humidity sensors. After the device definitions are made and the connection is estab-
lished, the addresses of each data in the device are defined on Kepware. Pre-determined
standardization rules were applied in defining data names. In this way, both name com-
plexities are prevented and identification is provided for devices to be defined in the
future. Two different methods are followed in publishing the data defined on Kepware to
other systems. Digitalization layers of the data are shown in the Fig. 4.hi The first of these methods is the database connection. Kepware’s datalogger plug is
used for database connection. Thanks to this plugin, it is ensured that the data flowing Cakir et al. Journal of Big Data (2022) 9:118 Page 11 of 24 Fig. 4 Digitalization layers of the data and communication protocols of the devices are shown on the
diagram. There are 5 types of devices that produce data in different formats and frequencies on the shop
floor. This data is digitalized using an OPC server and published via different methods such as MQTT, REST,
ODBC to the big data platform Fig. 5 Data transmission frequencies, streamed data volume, data transfer protocols, and device types are
described in the table. There are two types of injection molding machines as KraussMaffei and Engel. Data
frequencies are different because of machine specifications. Data compression rates differ according to data
types and average of the compression rate is 59:1. Thanks to the compression process, 19GB storage resource
is used instead of 1168GB Fig. 5 Data transmission frequencies, streamed data volume, data transfer protocols, and device types are
described in the table. There are two types of injection molding machines as KraussMaffei and Engel. Data
frequencies are different because of machine specifications. Data compression rates differ according to data
types and average of the compression rate is 59:1. Kepware Thanks to the compression process, 19GB storage resource
is used instead of 1168GB Fig. 5 Data transmission frequencies, streamed data volume, data transfer protocols, and device types are
described in the table. There are two types of injection molding machines as KraussMaffei and Engel. Data
frequencies are different because of machine specifications. Data compression rates differ according to data
types and average of the compression rate is 59:1. Thanks to the compression process, 19GB storage resource
is used instead of 1168GB through Kepware can be written to the desired relational database. Most of the data col-
lected by the injection machines are recorded in registers once in each cycle (the com-
pletion of the production of each part is called the cycle and the average cycle time of
the factory is 30 seconds). A database connection is provided over Kepware for the data
recorded in the cycle, and it is ensured that these data are written on the database at
the end of each cycle. The reason for choosing this method is that the data frequency
is small and short-term buffer areas are desired to be created on the database on local
servers. These buffer fields are important to prevent data loss when the connection with
remote servers is lost. The second method used to broadcast data over Kepware is streaming over the MQTT
protocol. For data flowing at high frequency (current, voltage, pressure), the IoT Gate-
way plug-in in the Kepware OPC server was used. The data defined on this plug-in can Cakir et al. Journal of Big Data (2022) 9:118 Page 12 of 24 Fig. 6 Data digitalization schema of DataCone.The data is collected from 4 different types of devices,
and it is published to the big data platform over two different methods. MQTT protocol is used to transfer
streaming data such as voltage, current, pressure, flow, etc. Batch data is inserted into a MYSQL database after
each machine cycle is finished. The shop floor data is transferred to the big data platform using those two
methods via Apache Nifi Fig. 6 Data digitalization schema of DataCone.The data is collected from 4 different types of devices,
and it is published to the big data platform over two different methods. MQTT protocol is used to transfer
streaming data such as voltage, current, pressure, flow, etc. Batch data is inserted into a MYSQL database after
each machine cycle is finished. Kepware The shop floor data is transferred to the big data platform using those two
methods via Apache Nifi be broadcast instantly over the MQTT protocol. In this way, the data that will be used
for the analysis to be made on the flowing data can be accessed in near real-time. Data
transmission frequencies are shown in the Fig. 5. PLC and OPC intergation This layer is the beginning of the journey of data. The data generated in the production
layer must be read from machines and sensors. There are different types of protocols for
collecting data from each data source. The Kepware OPC server, which can collect data
from various protocols, is used for this. In this layer, data is collected from machine-
specific protocols, PLCs, and sensors. In plastic injection machines, data is collected
from the Euromap63 module. The data collected from Euromap63 is collected on a cycle
basis and per second. Data from sensors such as environment and vibration are collected
every second with OPC UA. Energy analyzers, water collectors, and other equipment
data are collected from the PLC of the devices every second. In the production layer, all
the machines, devices, and sensors in the cell are connected to a common main panel,
therefore all data sources are connected to the network. Standardized names are used to describe the data correctly. Data names are deter-
mined for each device, all definitions are made on the OPC server according to these
names. After each data/tag is defined to the OPC server, it is published to the digital
layer according to its frequency and the characteristics of the data source. Due to the
features of the Euromap63 module, some data come once a cycle and some data come Cakir et al. Journal of Big Data (2022) 9:118 Page 13 of 24 Page 13 of 24 Fig. 7 Two types of data pipelines that are developed in Apache Nifi are used to collect data from injection
molding machines with different frequencies are shown in the figure. While the pipeline on the left side
is used to gather MQTT data every second, the other one collects the data produced every cycle from the
MYSQL database Fig. 7 Two types of data pipelines that are developed in Apache Nifi are used to collect data from injection
molding machines with different frequencies are shown in the figure. While the pipeline on the left side
is used to gather MQTT data every second, the other one collects the data produced every cycle from the
MYSQL database Fig. 8 Pipeline categorization of the devices in a production cell. All equipment in the production cells is
grouped by device categories in Apache Nifi to ensure ease of use. PLC and OPC intergation The data lineage can be captured from
group objects which are seen in the figure Fig. 8 Pipeline categorization of the devices in a production cell. All equipment in the production cells is
grouped by device categories in Apache Nifi to ensure ease of use. The data lineage can be captured from
group objects which are seen in the figure every second. Cycle-based incoming data is written to MySQL, and incoming data every
second is published with the MQTT protocol. All data from other devices are tagged
with the cycle number data received from the plastic injection machine and published
with the MQTT protocol every second. You can see this layer in Fig. 6 Streaming data processing layer In DataCone, Apache Spark Structured Streaming is utilized to transform JSON file
format to Parquet file format and save these files to HDFS which is the data lake of
DataCone. By way of parquet, we compress data by 15 times roughly and through the
columnar format of Parquet, we read fast OLAP query for batch processing. To read
data lying HDFS quicker, we utilize partitioning and repartition on Apache Spark, and
data is partitioned by day of a timestamp during saving Parquet data to HDFS. Spark
Structured Streaming read streams from Apache Kafka topics and read JSON data with
predefined JSON schema. Thus we will approach streaming more structured way and we
can manipulate data uncomplicatedly. For fault tolerance, Apache Spark uses checkpoint
to read data from source and by way of Apache Kafka on the off chance that any error
happens, Spark is able to proceed from the last correct Kafka offset. Data ingestion layerl For the workflow design, Apache NiFi is used as the medium for routing the data
as shown in Fig. 7, by dividing the operation into 2 parts which are time-based and
cycle-based workflows. Using NiFi processors, we were able to fetch IOT data from Cakir et al. Journal of Big Data (2022) 9:118 Page 14 of 24 the manufacturing side with MQTT protocol and ERP data from the ERP server with
DBCPService into our data platform. In DataCone, NiFi workflows were partitioned by
machine ID and all data was sent to Kafka every second in the first architecture. How-
ever, in many cases, these workflows did not fit ML Layer and cycle-based data was
duplicated. Since a few data is changed for each cycle which is between 30 and 100
seconds regard to mold and machine and other data is changed every second. Hence
workflow which is separated into device-based architecture consists of energy collector,
environment sensors, analyzer, Injection machine, and ERP data that is shown in Fig. 8. Ni-Fi has several processors that give real-time control that performs ETL basic to
make available connectors for the file system in the Hadoop Cluster, Elasticsearch,
and distributed messaging technologies such as Kafka. In DataCone, the proposed
NiFi Custom Processor consists of three processes: The first Extract Custom Pro-
cessor is responsible for delivering raw data (JSON format) information by using
MQTT Consumer which receives messages from MQTT broker and processed data
from ERP (CSV, JSON format) information with HTPP requests. The second Trans-
form Custom Processor alters dynamic raw data structure to desired data structure
using Jolt Transformation library that written in Java that allows a developer to con-
vert one JSON structure to another [39]. The last third Load Processor is loaded
streaming structured data using Kafka as a messaging system that publishes mes-
sages to Elasticsearch and Spark Streaming. Long term data storage In DataCone, HDFS is our parallel manner data lake which stored any kind of warm and
cold data in long term. Manufacturing data which can be divided into streaming data
and batch analysis results, ERP data, specific dictionaries, and other unstructured data
are stored in HDFS. Most of the data will be transformed to Parquet format because
we use mostly OLAP queries on HDFS for analytic results and read data lying on HDFS
faster. Apache Parquet is the performant columnar format and open-source format. It
is more efficient compared to row-based files like CSV files or semi-structured JSON
which is the main IOT data transferring format in our data platform. For the streaming
process, by the way of converting JSON file format to parquet format, we obtain space in
the disk by 15 times around. We also utilized data partitioning to increment the perfor-
mance of HDFS. Through Spark Streaming, before writing Parquet data to HDFS, we use
partitioning and repartition on Spark, and data is partitioned by day of the date. By the
way of partitioning, we can read faster with filtered data by timestamp. Workflow management layer In DataCone, Airflow has been used for several applications to schedule cron jobs in
place of crontab, execute the tasks, and monitor workflows on the Airflow web server. The user interface makes it simple to visualize DataCone pipelines running in produc-
tion, displays the states of currently active and past tasks, shows diagnostic information,
error logs about task execution, and troubleshoot issues when needed. In DataCone, object-oriented programming in Python is used in Spark, ETL jobs,
Machine Learning Products, and scripting. In this manner, the Python API structure in
Airflow matched our pipeline exceptionally well. Moreover, workflow implementation in Cakir et al. Journal of Big Data (2022) 9:118 Page 15 of 24 Airflow is extremely flexible, and the Python API structure utilized to write workflows is
simple and learn and understand [40] Machine learning deployment workflow with Air-
flow is shown. This workflow approach is utilized for our all machine learning use-cases
in production. Data messaging layerhl The data flow is designed according to the production technique of the manufactur-
ing company. Using Kafka is aimed to collect valuable process data without loss. In the
design created, the cell containing each plastic injection machine and all the devices
connected to the machine is considered as a factory. Therefore, separate topics were cre-
ated for each cell in Kafka. These topics are named according to the cell names and the
device the data is received, eg e117-anl. In DataCone, Kafka is managed through Nifi. A
topic is created with Nifi in Kafka. To write to the created topic, a PublishKafka Proces-
sor is created and a Producer writes data on the topic. Then, Consumer is created with
ConsumeKafka Processor to read the data from the topic. In this way, data flow is pro-
vided in real-time and without losing cell data. By creating a topic, consumer, and pro-
ducer over Nifi, Kafka’s management is managed from an interactive screen. Document database MongoDB database is installed on the servers in the cluster and is used to store the
JSON objects generated by the system. APIs of mobile applications and web-based dash-
boards read the data they need from the MongoDB database. The codes that periodically
calculate the data to be used in the established structure to prevent delays in the inter-
face and applications are managed by airflow. The outputs of these codes are saved in the
MongoDB database and are kept ready for APIs to read. For example, the data required
to be displayed on the production monitoring screens, which are custom dashboards
developed on flask for production, are calculated every 5 minutes by the python code
triggered by airflow and saved in the MongoDB database. When users want to access
information, it is queried from the MongoDB database by the API connected to the flask
interface and presented to the user quickly. In this way, delays are prevented and a con-
stant load is guaranteed in the system for the specified time period. Short term data storage Elasticsearch is a database where we keep hot and warm data and access data with fast
queries. Data are taken to Elasticsearch, together with indexes named for each device
according to device category, device number, and pipeline number, and month-year. These indexes are designed as 1 shard without replicas. The frequencies of the data in the
indexes are different. It has been designed so that production teams can quickly access
data. By easily accessing the data of each device, anyone authorized can see the data. For example, quality engineers can easily access the process data of a part produced 2
months ago with a part tag. It also has a design where data teams can easily extract data Page 16 of 24 Cakir et al. Journal of Big Data (2022) 9:118 Table 1 Naming conventions and device data sample table captured from DataCone’s master
database
Unique naming conventions are created for the manufacturing sector. Device category names are described with three
letters for example, anl stands fr analyzer and imm stands for injection molding machine. The Device number is started
from 10001 for each device category and increases sequentially. The pipeline number describes specific pipeline methods
for example 11 is used for real-time data pipelines. es_index stands for index name in Elasticsearch of device and pipeline
combination. It consists of device category, device number, and pipeline number
buss_unit
device_category
device_number
pipline_number
es_index
m14
anl
10001
11
anl1000111
m14
imm
10001
11
imm1000111
m14
tnh
10001
11
tnh1000111
m59
imm
10002
11
imm1000211 for fast analysis. Elasticsearch in the DataCone is not designed to store historical data, so
indexes must be deleted at certain times in order for Elasticsearch to always be fast. The
retention time of the indexes is designed according to the data frequencies. Delete poli-
cies that work every 6 months were created for cycle-based data, and a 2-monthly delete
policy was created for data received every second. for fast analysis. Elasticsearch in the DataCone is not designed to store historical data, so
indexes must be deleted at certain times in order for Elasticsearch to always be fast. The
retention time of the indexes is designed according to the data frequencies. Delete poli-
cies that work every 6 months were created for cycle-based data, and a 2-monthly delete
policy was created for data received every second. Real time dashboards Kibana is used for real-time monitoring of manufacturing fields and machine sta-
tuses. Since Kibana is an Elasticsearch product, the same indexes are used to make
graphics. Therefore, it is quite easy to draw graphics with drafts in Kibana. Produc-
tion monitoring screens that show each field’s machines’ working status and cycle
times are designed for manufacturing engineers and responsible. The screen named
production monitoring screen can be seen in Fig. 9. Kibana contains draft graphs and charts like line graphs, bar charts, radar charts, heat
maps, region maps, pie charts, gauge,s, etc. To monitor real-time data in every injection
molding manufacturing cell, machine-specific screens are designed. The screen shows
actual machine parameters like cylinder temperatures, pressures, volumes, etc. This
screen shows not only data generated on the machine but also environmental data, mold
data, and ERP production management data. Machine status, number of parts pro-
duced, last cycle time, real-time machine parameters, mold water temperature, ambient
temperature, and pressure are real-time data that can be viewed in this screen shown in
Fig. 10. Master data storage Descriptive master data such as the names, categories, and locations of the devices in
the big data system are kept in the MySQL database installed in the cluster. There are
three main tables in the database where device information is kept. The first of these
tables is the device category table. This table contains the categories of the devices
used in production and the descriptions of these categories. The second and most
important table is the device register table. This table contains business unit, device
number, pipeline number device category, and Elasticsearch index information for
each device. Elasticsearch indexes are created from a combination of device category,
device number, and pipeline number. Device numbers are given in each category in
increments of the order of newly added devices. The pipeline number indicates the Cakir et al. Journal of Big Data (2022) 9:118 Page 17 of 24 Fig. 9 Machine status dashboard shows whether machines are working or not. If it is working, the color of
the box is green. If it is not working, then the color is red. The average cycle time for each machine is shown
on the dashboard. Users can reach the detailed dashboards over the links on this dashboard Fig. 9 Machine status dashboard shows whether machines are working or not. If it is working, the color of
the box is green. If it is not working, then the color is red. The average cycle time for each machine is shown
on the dashboard. Users can reach the detailed dashboards over the links on this dashboard data transfer pipeline category as shown in Table 1. The last table in the database is
the table that specifies the locations of the business units. In this table, the country,
category, and facility information of each business unit number is kept. Newly added
business units can be followed from this table, and at the same time, this table is used
for country and facility-based reporting. Reporting tool When visualizing data with JSON data type we use the ajax method to get data in javas-
cript. After creating a template with HTML and CSS, inside javascript code, we use
plotly.js which is an interactive web graphics via javascript open-source graphing library. To make charts interactive with constantly updated data from put-up dash API URL we
turn ajax into a function to collaborate plotly data section. After changing other values Cakir et al. Journal of Big Data (2022) 9:118 Page 18 of 24 Fig. 10 Detailed machine dashboard shows near real-time process data such as pressure, time, volume,
speed, and temperature. Plots on the dashboard are mostly grouped by part number. Users can compare
different parts in terms of the process parameters by selecting part numbers using the drop-down menu on
the left corner. This dashboard is refreshed automatically every 5 s Fig. 10 Detailed machine dashboard shows near real-time process data such as pressure, time, volume,
speed, and temperature. Plots on the dashboard are mostly grouped by part number. Users can compare
different parts in terms of the process parameters by selecting part numbers using the drop-down menu on
the left corner. This dashboard is refreshed automatically every 5 s Fig. 10 Detailed machine dashboard shows near real-time process data such as pressure, time, volume,
speed, and temperature. Plots on the dashboard are mostly grouped by part number. Users can compare
different parts in terms of the process parameters by selecting part numbers using the drop-down menu on
the left corner. This dashboard is refreshed automatically every 5 s Fig. 11 The outputs of the artificial intelligence model which is responsible for detecting anomalies in the
production are shown on the smart production dashboard. The sum of the anomalies that occurred in each
hour on each machine is calculated and shown on a matrix on the right corner of the dashboard. This plot
helps manufacturing engineers to realize if there is a major problem in one of the hours of the day or one of
the machines for several hours Fig. 11 The outputs of the artificial intelligence model which is responsible for detecting anomalies in the
production are shown on the smart production dashboard. The sum of the anomalies that occurred in each
hour on each machine is calculated and shown on a matrix on the right corner of the dashboard. Reporting tool This plot
helps manufacturing engineers to realize if there is a major problem in one of the hours of the day or one of
the machines for several hours our charts are ready. One condition to active plotly library is that add extension inside
javascript code.l On the flask side, we merged dashboards’ HTML and js code with python to work with
API and much other stuff such as displaying on the website. Flask is very useful for dis-
playing constantly updated data, especially when working with HTML and js. Template
Inheritance in Flask permits developers to build a base template that can be overridden Cakir et al. Journal of Big Data (2022) 9:118 Page 19 of 24 Fig. 12 The radar map compares the quality product with the abnormal product in terms of the process
parameters. The scaled process parameters are placed around the circle. While the green area indicates the
quality product, the red area shows the abnormal one. The abnormal product can be analyzed in detail using
this radar map Fig. 12 The radar map compares the quality product with the abnormal product in terms of the process
parameters. The scaled process parameters are placed around the circle. While the green area indicates the
quality product, the red area shows the abnormal one. The abnormal product can be analyzed in detail using
this radar map Fig. 12 The radar map compares the quality product with the abnormal product in terms of the process
parameters. The scaled process parameters are placed around the circle. While the green area indicates the
quality product, the red area shows the abnormal one. The abnormal product can be analyzed in detail using
this radar map Fig. 13 The ranking of the impact of the parameters on the anomaly. 14 parameters that have more effect
than other process parameters on the anomaly of a sample product are listed on the bar chart Fig. 13 The ranking of the impact of the parameters on the anomaly. 14 parameters that have more effect
than other process parameters on the anomaly of a sample product are listed on the bar chart Cakir et al. Journal of Big Data (2022) 9:118 Page 20 of 24 by child template thus in dashboard1 we inherited a base_dashboard.html. Render_tem-
plate function helps us to use @app.route. As can be seen on Fig. 11 there are 5 charts in dashboard2. Reporting tool They represent 5 data
from linked machines; Energy Track, Anomaly Situations, Alarms, Anomaly Situation
List, and Anomaly Situation Number Track. An indicator chart to show daily consump-
tion and its rate to weekly consumption. For anomaly situations in each machine, radar
charts have been used. With javascript capability, the tables have been created. And
lastly, a Heatmap with Categorical Axis Labels has been created to show the Anomaly
Situation Number Track with rising importance colors. Dashboard1 graph data shows
the most troubled parameters and the last 10 cycles. Each production machine has its
own data to be examined. If it’s functioning well the color will be seen green if not it will
turn yellow or red according to problems. The tables section demonstrates Cycle time,
anomaly parameter, and when they have been analyzed. Also, we can deduce meanly and
momentary consumption from tables. AI based real time anomaly detection It is very important to track the production process in production lines, for producing
defect-free parts, and to detect errors. Despite the warnings given by the machines at
specified thresholds and the operators’ knowledge of the process, it is not possible to
understand the events taking place in the capillaries of the machine with a human eye. In the study, with the data collected from different sources on a per-second and cycle
basis, effects of small process variable differences on the part quality are aimed to be
detected. In addition, parameters that have the most effect on the process anomaly will
be analyzed. For each cycle, the anomalies that occur during the production of the part are detected. For the cycles that have anomalies, the parameters are compared with the golden cycle. In the study, process parameters such as temperatures, pressures, forces, strokes, and
cycle time are collected from the injection molding machine, ambient temperature and Fig. 14 This figure shows autoencoder algorithm based reconstruction error of 60 product that produced
sequentially. The reconstruction error threshold is determined as 4. The products which has reconstruction
error more than 4, are labeled as abnormal products. Its clearly seen on the plot, there is some issue between
348. and 356. products Fig. 14 This figure shows autoencoder algorithm based reconstruction error of 60 product that produced
sequentially. The reconstruction error threshold is determined as 4. The products which has reconstruction
error more than 4, are labeled as abnormal products. Its clearly seen on the plot, there is some issue between
348. and 356. products Cakir et al. Journal of Big Data (2022) 9:118 Page 21 of 24 ambient humidity data are collected using the ambient sensor. An artificial neural net-
work algorithm called Autoencoder is chosen to be used for unsupervised learning. With the anomaly detection algorithm developed based on Autoencoder, the pattern of
the process data is continuously followed and comparisons are made for each cycle. If
there is a cycle that progresses differently from the general pattern, it is recorded as an
abnormal cycle. With the detected anomalies, the further downstream of the process is
predicted. Figure 12 shows how the abnormal cycle differs from the general pattern. This analy-
sis is the first indication of the abnormality that started in the process. Figure 13 shows
which parameters caused this abnormality the most. AI based real time anomaly detection With this developed algorithm, the
heartbeat of the machine is controlled and warnings are given on the screens. In Fig. 14,
it is observed how the process starts to change after the abnormality is detected and the
process goes abnormally within a certain range according to reconstruction error.hff The study shows how small parameter differences in process parameters affect pro-
duction. While warning systems can only be created with sharp increases in the param-
eters determined in classical systems, with this approach all parameters can be evaluated
together in real-time with process data and differences can be determined. With this
more holistic approach, it is aimed to prevent the process that will cause errors, to pro-
vide energy efficiency, and to increase efficiency by reducing both quality and cost. Acknowledgements g
It is dedicated to the memory of my beloved father, Süleyman Turhan Çakır, who has always supported me throughout
my life. Conclusion In conclusion, the growing need to data management at manufacturing industry and
demand forecasting is derived by globalization and increasing digital transformation
approaches. In this study, we performed a through local open-source methodologies
for effective-low cost applications of predictive big data analytics including anomaly
detection forecasting example. The study overviewed the real time big data design and
analytics methods applied to manufacturing processes and provided a comparative cat-
egorization of them. We collected and analyzed these studies with respect to methods
and techniques used in production prediction. Several open-source lambda architec-
ture technologies are identified and studied with their pros and cons. The corresponding
choices are observed as the common low-cost and easy-applicable techniques, among
others. The study also pointed to the fact that data management and real-time optimiza-
tion models can be used to improve the accuracy of time-dependent analytics, sequen-
tial time-series prediction, through formulating and optimizing a cost function for the
fitting of the predictions to data in real time nature. One key finding from our study
the existing literature was that there is a very limited research conducted on the appli-
cations of open-source designed, a real-time predictive big data analytics in large scale
plastic injection moulding machines in manufacturing at scale and reverse applications
for production, maintenance, and other deployments. As a result, we propose a big data
architecture design, DataCone, using low-cost effective on-premise open source big data
technologies to meet the needs of manufacturing companies in many operations. All in
all, this work explored how operational detection approaches alongside different types
of predictive maintenance algorithms, autoencoder, can be used for the abnormal cycle
differs from the general pattern. This alone shows how small parameter differences in
process parameters affect production. While warning systems can only be created with
sharp increases in the parameters determined in classical systems, with this approach
all parameters can be evaluated together in real-time without latency in the application. Discussion and evaluation With this case study, a big data platform was developed for the manufacturing company,
which the company did not have before. Thanks to this platform, large volume and high
frequency data were collected from many equipments in the production area. With the
platform, the traceability of the process in the field has been increased and the collected
data has provided input to many analytical studies. By making the data manageable and
traceable, productivity gains have been achieved in many different areas such as error
detection, root cause analysis and process design. At the same time, the collection and
accumulation of data plays an important role for future artificial intelligence studies. Data analysis software has been integrated to be used in studies to analyze the data col-
lected within the platform. Thanks to these software technologies, it is aimed to shorten
the project durations by creating a collaborative working platform for data analysts, data
scientists and data engineers. New devices and data sources can be integrated into the
created platform quickly and easily. In this way, the integration stages, which are the
most critical stages of data projects, can be completed in a short time. With the artificial
intelligence-based anomaly detection application developed and implemented entirely
on the platform, the quality control process, which is a very critical and manual process
for production, has been automated. In this way, machine time and man-hour savings
are achieved. Cakir et al. Journal of Big Data (2022) 9:118 Page 22 of 24 Author contributions AÇ designed the novel big data architecture of DataCone which is suitable for manufacturing and he calculated the
hardware requirements of infrastructure. ÖA and HFD installed and integrated the software which is indicated in big data
architecture design and they developed data pipelines. AY analyzed the production data and contributed to develop-
ing anomaly detection model and design of the smart production dashboards. All authors read and approved the final
manuscript. Future works In our next publications, big data architectures and machine learning models, which are
implemented to the continuous production line, will be explored. Continuous and cellu-
lar production will be compared in terms of architectures, pipelines, and analytics of big
data. In addition, operational cost optimization of the big data platforms will be studied. Availability of data and materials y
The datasets generated and/or analysed during the current study are not publicly available due to the confidentiality
of company data but an anonymized sample of the data are available from the corresponding author on reasonable
request. Page 23 of 24 Cakir et al. Journal of Big Data (2022) 9:118 Consent for publication
Not applicable. Competing interests
The authors declare that they have no competing interests. Competing interests
The authors declare that they have no competing interests. Received: 10 March 2022 Accepted: 29 November 2022 Received: 10 March 2022 Accepted: 29 November 2022 References 1. Mourtzis D, Vlachou E, Milas N. Industrial big data as a result of iot adoption in manufacturing. Procedia CIRP. 2016;55:290–5. https://doi.org/10.1016/j.procir.2016.07.038. 1. Mourtzis D, Vlachou E, Milas N. Industrial big data as a result of iot adoption in manufacturing. Procedia CIRP. 2016;55:290–5. https://doi.org/10.1016/j.procir.2016.07.038. 2. Liu R, Isah H, Zulkernine F. A big data lake for multilevel streaming analytics. 2020 1st International Conference on
Big Data Analytics and Practices (IBDAP). 2020 1st International Conference on Big Data Analytics and Practices
(IBDAP) (2009). https://doi.org/10.1109/IBDAP50342.2020.9245460. p
g
3. Belhadi A, Zkik K, Cherrafi A, Yusof SM, Fezazi SE. Understanding the capabilities of big data analytics for manufac-
turing process: insights from literature review and multiple case study. Comput Ind Eng. 2019. https://doi.org/10.
1016/j.cie.2019.106099. g
3. Belhadi A, Zkik K, Cherrafi A, Yusof SM, Fezazi SE. Understanding the capabilities of big data analytics for manufac-
turing process: insights from literature review and multiple case study. Comput Ind Eng. 2019. https://doi.org/10.
1016/j.cie.2019.106099. j
4. IBM Analytics: IBM Industry Model support for a data lake architecture (2016). https://www.ibm.com/downloads/
cas/DNKPJ80Q Accessed 26 Apr 2021. j
4. IBM Analytics: IBM Industry Model support for a data lake architecture (2016). https://www.ibm.com/downloads/
cas/DNKPJ80Q Accessed 26 Apr 2021. 5. Tao F, Qi Q, Liu A, Kusiak A. Data-driven smart manufacturing. J Manuf Syst. 2018;48:157–69. https://doi.org/10.
1016/j.jmsy.2018.01.006. 6. Shao G, Jain S, Shin S-J. Data analytics using simulation for smart manufacturing. Proceedings of the Winter Simula-
tion Conference. 2014. https://doi.org/10.1109/WSC.2014.7020063. p
g
7. Syafrudin M, Fitriyani NL, Li D, Alfian G, Rhee J, Kang Y-S. An open source-based real-time data processing
ture framework for manufacturing sustainability. Sustainability. 2017. https://doi.org/10.3390/su9112139 p
g
7. Syafrudin M, Fitriyani NL, Li D, Alfian G, Rhee J, Kang Y-S. An open source-based real-time data processing architec-
t
f
k f
f
t
i
t i
bilit
S
t i
bilit
2017 htt
//d i
/10 3390/
9112139 8. Dai H-N, Wang H, Xu G, Wan J. Big data analytics for manufacturing internet of things: opportunities,
enabling technologies. Enterprise Inf Syst. 2019. https://doi.org/10.1080/17517575.2019.1633689. 8. Dai H-N, Wang H, Xu G, Wan J. Big data analytics for manufacturing internet of things: opportunities, challenges and
enabling technologies Enterprise Inf Syst 2019 https://doi org/10 1080/17517575 2019 1633689 g
g
p
y
p
g
9. Wilcox T, Jin N, Flach P, Thumim J. A big data platform for smart meter data analytics. Comput Ind. 2019;105:250–9. https://doi.org/10.1016/j.compind.2018.12.010. p
g
j
p
10. References White T. Hadoop: The Definitive Guide. Sebastopol: O’Reilly Media Inc; 2009. 11. Murthy A, Vavilapalli VK. Apache Hadoop YARN. Upper Saddle River: Addison-Wesley; 2014. 11. Murthy A, Vavilapalli VK. Apache Hadoop YARN. Upper Saddle River: Addison-Wesley 12. Zaharia M, Xin RS, Wendell P, Das T, Armbrust M, Dave A, Meng X, Rosen J, Venkataraman S, Franklin MJ, Ghodsi A,
Gonzalez J, Shenker S, Stoica I. Apache spark: a unified engine for big data processing. Commun ACM. 2016. https://
doi.org/10.1145/2934664. g
13. Kuć R, Rogoziński M. Mastering Elasticsearch. Birmingham: Packt Publishing; 2015. 4. https://en.wikipedia.org/wiki/Apache_NiFi Accessed 7 Feb 2021 15. Pandya A, Kostakos P, Mehmood H, Cortes M. Privacy preserving sentiment analysis on multiple edge data streams
with apache nifi. In: Proceedings of European Intelligence and Security Informatics Conference (EISIC) (2019). https://doi.org/10.1109/EISIC49498.2019.9108851. p
g
16. Samal B, Panda M. Real time product feedback review and analysis using apache technologies and nosql database. Int J Eng Comput Sci. 2017. https://doi.org/10.18535/ijecs/v6i10.04. p
g
16. Samal B, Panda M. Real time product feedback review and analysis using apache technologies and nosql database. Int J Eng Comput Sci. 2017. https://doi.org/10.18535/ijecs/v6i10.04. Soner K, Upadhyay H. A survey: Ddos attack on internet of things. 18. Kreps J, Narkhede N, Rao J. Kafka: a distributed messaging system for log processing. In: Proceedings of the NetDB,
Athens, Greece 2011. 18. Kreps J, Narkhede N, Rao J. Kafka: a distributed messaging system for log processing. In: Proceedings of the NetDB,
Athens, Greece 2011. 19. https://kafka.apache.org/intro Accessed 24 Mar 2021. 20. What is Elasticsearch. https://www.elastic.co/guide/en/elasticsearch/reference/master/elasticsearch-intro.html
Accessed 2 Apr 2021. 20. What is Elasticsearch. https://www.elastic.co/guide/en/elasticsearch/reference/master/elasticsearch-intro.html
Accessed 2 Apr 2021. 21. Mu C, Zhao J, Yang G, Zhang J, Yan Z. Towards practical visual search engine within elasticsearch. 2018. arxiv:1806.
08896. 21. Mu C, Zhao J, Yang G, Zhang J, Yan Z. Towards practical visual search engine within elasticsearch. 2018. arxiv:1806.
08896. 22. Srivastava A, Miller D. Elasticsearch 7 Quick Start Guide. Birmingham: Packt Publishing; 2019. 22. Srivastava A, Miller D. Elasticsearch 7 Quick Start Guide. Birmingham: Packt Publishing; 201 23. Kuc R, Rogozinski M. Elasticsearch Server. Birmingham: Packt Publishing; 2014. ogozinski M. Elasticsearch Server. Birmingham: Packt Publishing; 20 g
g
g
24. Chiary MR, Anand R. Hadoop cluster on linode using ambari for improving task assignment scheme running in the
clouds Int J Comput Sci Inf Technol 2015;6(1):586–9 24. Chiary MR, Anand R. Hadoop cluster on linode using a 24. References Learning Kibana 7: Build Powerful Elastic Dashboards with Kibana’s Data. Birmingham: Packt
Publishing; 2019. g;
35. Build visualizations simply and intuitively. https://www.elastic.co/kibana Accessed 11 Mar 2021. g
35. Build visualizations simply and intuitively. https://www.elastic.co/kibana Accessed 11 Mar 2021. p y
y
p
36. Flask Web Development, One Drop At A Time. https://readthedocs.org/projects/flask/ Accessed 16 Apr 2021. 37
Ab
t EUROMAP htt
//
/ b
t
/ b
t
A
d 13 J
2021 p y
y
p
36. Flask Web Development, One Drop At A Time. https://readthedocs.org/projects/flask/ Accessed 16 Apr 2021. 36. Flask Web Development, One Drop At A Time. https://readthedocs.org/projects/flask/ Accessed p
p
p
g p
jl
p
37. About EUROMAP. https://www.euromap.org/about-us/about-euromap Accessed 13 Jan 2021. p
p
p
g p
jl
37. About EUROMAP. https://www.euromap.org/about-us/about-euromap Accessed p
p
g
p
38. Plastics and Rubber Machinery. https://opcfoundation.org/markets-collaboration/plastics-and-rubber-machinery/
Accessed 13 Jan 2021. 38. Plastics and Rubber Machinery. https://opcfoundation.org/markets-collaboration/plastics-and-rubber-machinery/
Accessed 13 Jan 2021. 39. Jolt. https://github.com/bazaarvoice/jolt Accessed 16 Feb 2021. 9. Jolt. https://github.com/bazaarvoice/jolt Accessed 16 Feb 2021 p
g
j
40. Mitchell R, Loıc Pottier SJ, da Silva RF. Exploration of workflow management systems emerging features from users
perspectives. In: IEEE International Conference on Big Data. 2019. https://doi.org/10.1109/BigData47090.2019.90054
94. p
g
j
40. Mitchell R, Loıc Pottier SJ, da Silva RF. Exploration of workflow management systems emerging features from users
perspectives. In: IEEE International Conference on Big Data. 2019. https://doi.org/10.1109/BigData47090.2019.90054
94. References Chiary MR, Anand R. Hadoop cluster on linode using ambari for improving task assignment scheme running in the
clouds. Int J Comput Sci Inf Technol. 2015;6(1):586–9. 24. Chiary MR, Anand R. Hadoop cluster on linode using a
clouds. Int J Comput Sci Inf Technol. 2015;6(1):586–9. clouds. Int J Comput Sci Inf Technol. 2015;6(1):586–9. p
25. Erraissi A, Belangour A, Tragha A. A big data hadoop building blocks comparative study. Int J Comput Trends Tech- p
25. Erraissi A, Belangour A, Tragha A. A big data hadoop building blocks comparative study. Int J Comput Trends Tech-
l 2017 48(1) 36 40 h
//d i
/10 14445/22312803/IJCTT V48P109 25. Erraissi A, Belangour A, Tragha A. A big data hadoop building blocks comparative study. Int J Comput Trends Tech-
nol. 2017;48(1):36–40. https://doi.org/10.14445/22312803/IJCTT-V48P109. nol. 2017;48(1):36–40. https://doi.org/10.14445/22312803/IJC 26. John T, Misra P. Data Lake for Enterprises. Birmingham: Packt; 2017. p
g
27. Salloum S, Dautov R, Chen X, Peng PX, Huang JZ. Big data analytics on apache spark. Int J Data Sci Anal. 2016;1:145–64. 27. Salloum S, Dautov R, Chen X, Peng PX, Huang JZ. Big data analytics on apache spark. Int J Data Sci Anal
2016;1:145–64. 28. Shoro AG, Soomro TR. Big data analysis: Ap spark perspective. Global J Comput Sci Technol 2015;15(1). 29. Above the clouds: A berkeley view of cloud computing. Technical report, University of California at Berkley. 2009 Above the clouds: A berkeley view of cloud computing. Technical 29. Above the clouds: A berkeley view of cloud computing. Technical report, University of California at Berkley. 2009. 30. https://databricks.com/glossary/what-is-parquet Accessed 17 Mar 2021. y
p
g
p
y
y
30. https://databricks.com/glossary/what-is-parquet Accessed 17 Mar 2021. 30. https://databricks.com/glossary/what-is-parquet Accessed 17 Mar 2021. https://databricks.com/glossary/what-is-parquet Accessed 17 Mar 31. https://www.geeksforgeeks.org/mongodb-an-introduction/ Accessed 4 Jul 2021. https://www.geeksforgeeks.org/mongodb-an-introduction/ Acce 32. Mongodb—a comparison with nosql databases. Int J Sci Eng Res. 2016. Cakir et al. Journal of Big Data (2022) 9:118 Page 24 of 24 33. Beauchemin M. Airflow: a workflow management platform. https://medium.com/airbnb-engineering/airflow-l 33. Beauchemin M. Airflow: a workflow management platform. https://medium.com/airbnb-engineering/airflow-
aworkflow management platform 46318b977fd8 Accessed 12 Mar 2021 33. Beauchemin M. Airflow: a workflow management platform. https://mediu
aworkflow-management-platform-46318b977fd8 Accessed 12 Mar 2021. 33. Beauchemin M. Airflow: a workflow management platform. https://mediu
aworkflow-management-platform-46318b977fd8 Accessed 12 Mar 2021. 34. Srivastava A, Azarmi B. Learning Kibana 7: Build Powerful Elastic Dashboards with Kibana’s Data. Birmingham: Packt
Publishing; 2019. 34. Srivastava A, Azarmi B. Publisher’s Note Publisher s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
|
https://openalex.org/W4378172330
|
https://link.springer.com/content/pdf/10.1007/s00417-023-06095-0.pdf
|
English
| null |
Safety of intracameral application of moxifloxacin and dexamethasone (Vigadexa®) after phacoemulsification surgery
|
Graefe's archive for clinical and experimental ophthalmology
| 2,023
|
cc-by
| 5,632
|
* Alejandro Tello
alejandrotello@gmail.com CATARACT CATARACT CATARACT Abstract Background Intracameral antibiotics, such as moxifloxacin and cefuroxime, are safe to corneal endothelial cells and effective
prophylaxis of endophthalmitis after cataract surgery. Corneal endothelial cells decrease in density after cataract surgery. Any substance used in the anterior chamber may affect corneal endothelial cells and lead to a greater decrease in density. This study wants to determine the percentage of endothelial cell loss after cataract extraction by phacoemulsification with
off-label intracameral injection of moxifloxacin and dexamethasone (Vigadexa®). fl
Methods An observational retrospective study was performed. The clinical records of patients undergoing cataract surgery by phaco-
emulsification plus intracameral injection of Vigadexa® were analyzed. Endothelial cell loss (ECL) was calculated using preoperative
and postoperative endothelial cell density. The relation of endothelial cell loss with cataract grade using LOCS III classification, total
surgery time, total ultrasound time, total longitudinal power time, total torsional amplitude time, total aspiration time, estimated fluid
usage, and cumulative dissipated energy (CDE) was studied using univariate linear regression analysis and logistic regression analysis. Results The median loss of corneal endothelial cells was 4.6%, interquartile range 0 to 10.4%. Nuclear color and CDE were
associated with increased ECL. ECL>10% was associated with age and total ultrasound time in seconds. Conclusions The endothelial cell loss after the intracameral use of Vigadexa® at the end of cataract surgery was similar to the
reported in other studies of cataract surgery without the use of intracameral prophylaxis for postoperative endophthalmitis (POE). This study confirmed the association of CDE and nuclear opalescence grade with postoperative corneal endothelial cell loss. Keywords Cataract · Phacoemulsification · Endothelial cell count · Endothelial cell loss · Prophylaxis of endophthalmitis Keywords Cataract · Phacoemulsification · Endothelial cell count · Endothelial cell loss · Prophy What is known: The use of intracameral antibiotics as prophylaxis for endophthalmitis is safe and effective. The use of intracameral antibiotics as prophylaxis for endophthalmitis is safe and effective. What is new: The additional use of intracameral dexamethasone after phacoemulsification, as in the combination of moxifloxacin
and dexamethasone (Vigadexa®), did not show an increase in endothelial cell loss. The additional use of intracameral dexamethasone after phacoemulsification, as in the combination of moxifloxacin
and dexamethasone (Vigadexa®), did not show an increase in endothelial cell loss. The percentage of endothelial cell loss doubles for every 5 units increase of CDE. The percentage of endothelial cell loss doubles for every 5 units increase of CDE. Safety of intracameral application of moxifloxacin
and dexamethasone (Vigadexa®) after phacoemulsification surgery
Virgilio Galvis1,2,3 · Angelica Maria Prada1,2,3 · Alejandro Tello1,2,3,4 · Maria Margarita Parra2,4 ·
Paul Anthony Camacho2,3 · María Paz Polit2,3 Virgilio Galvis1,2,3 · Angelica Maria Prada1,2,3 · Alejandro Tello1,2,3,4 · Maria Margarita Parra2,4 ·
Paul Anthony Camacho2,3 · María Paz Polit2,3 Received: 15 September 2022 / Revised: 19 April 2023 / Accepted: 26 April 2023 / Published online: 25 May 2023
© The Author(s) 2023 2
Universidad Autónoma de Bucaramanga (UNAB),
Bucaramanga, Colombia Graefe's Archive for Clinical and Experimental Ophthalmology (2023) 261:3215–3221
https://doi.org/10.1007/s00417-023-06095-0 Graefe's Archive for Clinical and Experimental Ophthalmology (2023) 261:3215–3221
https://doi.org/10.1007/s00417-023-06095-0 Graefe's Archive for Clinical and Experimental Ophthalmology (2023) 261:3215–3221
https://doi.org/10.1007/s00417-023-06095-0 Introduction Cataract affects 94 million people worldwide and is the most
prevalent cause of vision impairment and blindness [1]. Cat-
aract surgery rates continue to grow globally, and in some
areas of the world at a rapid rate. In Latin America they
increased by 47% from 2008 to 2013, reaching 2,672 sur-
geries per 1 million inhabitants [2]. Postoperative endoph-
thalmitis (POE) is a severe complication of cataract surgery. Rangel et al. reported phthisis bulbi in 5.7% endophthalmitis
cases related to intraocular surgery [3]. fi
It is therefore very important that the substances injected
intraocularly have no harmful effects on corneal endothelial cells. Experimentally, it has been shown that intracamerally injected
preservative-free 0.5% moxifloxacin/0.1% dexamethasone oph-
thalmic solution (Vigadexa, Alcon, Fort Worth, TX, USA) was
safe on HCEC in an in vivo rabbit model [22]. This agrees with
other in vitro studies, which used moxifloxacin (Vigamox®) in
cultured HCECs [23–25]. However, other researchers have found
a dose-dependent damage to HCECs [26]. On the other hand,
intracameral moxifloxacin (both off-label Vigamox® and for-
mulations made for intraocular use) has been extensively used
in humans, and no significant ECL has been reported [26–28].lf The European Society of Cataract and Refractive
Surgeons (ESCRS) found that intracameral injection of
cefuroxime at the end of cataract surgery reduced the inci-
dence of endophthalmitis fivefold [4]. Given the evident
difference found while conducting the study, the Data
Monitoring Committee Monitoring advised that it would
be unethical to finish the clinical trial as planned, and
recruitment was closed early [4]. Melega et al. found a
significant reduction in the incidence of endophthalmitis
in patients treated with moxifloxacin at the end of cataract
surgery compared with those without intracameral anti-
biotic, 0.05% and 0.38%, respectively [5]. A recent sur-
vey among members of the American Society of Cataract
and Refractive Surgery (ASCRS) found a rise in cataract
surgeons using intracameral antibiotic prophylaxis com-
pared to 2007 [6]. The use of intracameral antibiotics
at the conclusion of cataract surgery was more frequent
among European respondents than among US respond-
ents, 70% vs 30%, respectively [6]. The 2022 American
Academy of Ophthalmology (AAO) Cataract Preferred
Practice Pattern Guidelines and the 2013 ESCRS guide-
lines for prevention and treatment of endophthalmitis [7]
agree that there is strong evidence supporting the safety
and efficacy of the intracameral injection of antibiotic
as prophylaxis for POE. Abstract The percentage of endothelial cell loss doubles for every 5 units increase of CDE. * Alejandro Tello
alejandrotello@gmail.com 1
Centro Oftalmológico Virgilio Galvis, Calle 158 20–95,
Consultorio 301, Torre C, Cañaveral, Floridablanca,
Santander, Colombia 4
Universidad Industrial de Santander (UIS), Bucaramanga,
Colombia 2
Universidad Autónoma de Bucaramanga (UNAB),
Bucaramanga, Colombia :(0121 3456789)
3 Graefe's Archive for Clinical and Experimental Ophthalmology (2023) 261:3215–3221 3216 irreversible corneal edema (pseudophakic bullous keratopathy,
PBK) may present and a corneal transplant may be required. PBK is the main cause of keratoplasty after cataract surgery
[18–20]. Toxicity to HCEC and toxic anterior segment syn-
drome (TASS) are potential concerns when using intraocular
substances. Toxic anterior segment syndrome (TASS) is a
severe sterile inflammatory complication of cataract surgery
[21] After TASS, HCEC have been reported to have less den-
sity, higher coefficient of variation, and less hexagonality [21]. Introduction A recent systematic review and
meta-analysis confirmed the benefit of using intracameral
antibiotics at the end of cataract surgery in reducing POE
rates [8]. Given the evidence, it is our belief that intraca-
meral antibiotic at the conclusion of cataract surgery is the
best practice for the prophylaxis of POE. i
Therefore, the idea of adding the anti-inflammatory effect
of dexamethasone to the prophylactic antibiotic seems to be
very reasonable. The objective of the present study was to
evaluate the ECL in eyes that received an off-label intraca-
meral injection of Vigadexa® as prophylaxis for POE at the
end of cataract surgery. Methods A retrospective observational study was performed. The
clinical records of patients undergoing cataract extraction
surgery by coaxial microincision phacoemulsification from
January to June 2016 were evaluated. All surgeries were
performed by a single surgeon (VG) using the Centurion
Vision System ™ with the Intrepid® Balanced tip (Alcon). To be eligible for inclusion, patients must have had an intra-
cameral injection of Vigadexa® at the end of surgery. Eyes
were excluded from the study if there were records of previ-
ous intraocular surgery, combined glaucoma and cataract
surgery, uveitis, and/or corneal endothelial dystrophy. Also,
eyes with intraoperative complications, requiring the use of
adrenaline in the anterior chamber or the use of iris retractor
hooks, were excluded. Study protocol was approved by the
ethical committee at Fundación Oftalmologica de Santander
(FOSCAL). All procedures performed involving human par-
ticipants were in accordance with the ethical standards at
FOSCAL clinic and with the 1964 Helsinki Declaration and
its later amendments or comparable ethical standards. All
patients gave written consent for the use of their clinical data
for research and publication purposes. On another note, the intraocular use of steroids, such as
dexamethasone and triamcinolone, has proven to be safe
and effective in managing intraocular inflammation [9–12]. Intraocular steroids can be used as intravitreal injections
[13], trans-zonular injections [14], injections into the anterior
chamber [15], or with delayed release intravitreal devices [16]. One of the risks that arise when using substances injected
in the anterior chamber is the toxicity to the human corneal
endothelial cells (HCEC). HCEC have mitosis almost com-
pletely inhibited in vivo [17]. Therefore, if the ECL is sig-
nificant and the postoperative density is very low, secondary On another note, the intraocular use of steroids, such as
dexamethasone and triamcinolone, has proven to be safe
and effective in managing intraocular inflammation [9–12]. Intraocular steroids can be used as intravitreal injections
[13], trans-zonular injections [14], injections into the anterior
chamber [15], or with delayed release intravitreal devices [16]. One of the risks that arise when using substances injected
in the anterior chamber is the toxicity to the human corneal
endothelial cells (HCEC). HCEC have mitosis almost com-
pletely inhibited in vivo [17]. Therefore, if the ECL is sig-
nificant and the postoperative density is very low, secondary 3 3 3217 Graefe's Archive for Clinical and Experimental Ophthalmology (2023) 261:3215–3221 descriptive statistics, estimating the measures of central ten-
dency and dispersion. Methods Normality was evaluated using the
Shapiro–Wilk test. The mean and standard deviation are
reported unless specified otherwise. Differences between
pre- and post-endothelial cell characteristics were evalu-
ated using the Wilcoxon signed-rank test. Univariate and
multivariate lineal regression analysis was done with ECL
as the outcome measure. Logistic univariate and multi-
variate regression analysis was used to estimate the odds
of ECL>10%. ECL of 10% is the value of the third quar-
tile of ECL in the sample, so it was used as the cut off for
the dichotomized ECL. A stepwise multivariable analysis
was performed. Missing data was handled using pairwise
deletion. A two-sided P <0.05 was considered statistically
significant. HCEC were evaluated using a non-contact specular micro-
scope (SP3000P, Topcon, Tokyo, Japan). Preoperative and
3-month postoperative endothelial cell density, coefficient of
variation, percentage of hexagonal cells, and mean size were
collected. The percentage of ECL was defined as [(preopera-
tive endothelial cell density − postoperative endothelial cell
density)/preoperative endothelial density] × 100. y p
p
y
Lens opacity classification system III (LOCS III) was
used to grade all cataracts. The LOCS III evaluates four
aspects of the crystalline lens, nuclear opalescence (NO),
nuclear color (NC), cortical opacity (C), and posterior sub-
capsular opacity (P). The grades are in the decimal scale,
NO and NC from 0.1 to 6.9, and C and P from 0.1 to 5.9. The
procedure to grade the cataract has already been described
[29]. All cataracts were graded by one surgeon. The param-
eters used during the surgery were adjusted according to the
classification of the cataract. Cataracts graded NO 0 to 4.9,
NC 0 to 4.9, P 0 to 5, and C 0 to 5 were considered to be
soft to medium in hardness. For such cataracts, the param-
eters used were flow/aspiration rate of 25 to 50 cm3/min,
torsional amplitude between 20 and 50%, and vacuum from
100 to 650 mm Hg. Cataracts graded NO 5 or more and NC
5 or more were considered hard. For such hard cataracts,
the torsional amplitude was increased to a range between 30
and 70%, without change in flow/aspiration rate or vacuum. Sample size calculation The normal decrease in endothelial cell count annually is
around 0.53% [30]. ECL after cataract surgery with phaco-
emulsification has been reported to be 11.6±14.3% [28]. Thus, to detect a mean difference between pre- and post-
operative endothelial cell count of 11.6% with 80% power
using a 5% level two-sided test, the sample size was calcu-
lated to be 23 eyes. l
All cataract surgeries were performed with the “divide and
conquer” technique. The combination of 3% sodium hyaluro-
nate and 4% chondroitin sulfate (Viscoat®, Alcon, Forth Worth,
TX, USA) was used in all surgeries. At the end of the pro-
cedure, undiluted Vigadexa® 0.05ml (moxifloxacin 0.5% and
dexamethasone 0.1%) sterile ophthalmic solution was admin-
istered intracamerally. Such volume corresponds to 250 μg of
moxifloxacin and 50 μg of dexamethasone. The intraocular use
of Vigadexa® is off-label. Patients also received standard post-
operative treatment with topical moxifloxacin 0.5% one drop
every 3 h for 1 week and prednisolone 1% 1 drop four times a
day and tapering off over a period of 4 weeks. Results A total of 159 eyes of 101 patients were included in the
study; 46.5% were men, and 50.3% were right eyes. The
average age was 67.4 ± 10.3 years (34–87 years). Preopera-
tive LOCS III classification, biometric measurements, and
intraoperative parameters are presented in Table 1. Data for
LOCS III classification was available for all eyes. Ocular
biometry data was measured using an optical biometer (Len-
star, Haag Streit) in 154 (96,8%), and in 5 eyes, the opacity
of the cataract prevented the use of the optical biometer; in
which case, the ultrasound biometer was used (OcuScan,
Alcon). There were missing values for LT, ACD, torsional
amplitude time, longitudinal power time, total ultrasound
time, and total surgery time. The percentage of missing data
across the variables varied between 1.8% (n=156 for ACD)
and 9.4% (n=134 for LT). Table 1 provides the number of
eyes with data available for each variable. f
Preoperative ocular biometry data was collected from clini-
cal records. Ocular biometry data included axial length (AL),
lens thickness (LT), and anterior chamber depth (ACD). For
ocular biometry, an optical biometry was the standard exam
(Lenstar, Haag Streit), in eyes where opacity prevented the
performance of the optical biometer, and ultrasound biometry
was the alternative exam. Intraoperative parameters from the
Centurion® device were obtained, which included total sur-
gery time, total ultrasound time, total longitudinal power time,
total torsional amplitude time, total aspiration time, estimated
fluid usage, and cumulative dissipated energy (CDE). Changes in parameters of corneal endothelium are shown
in Table 2. Data of endothelial cell parameters were avail-
able for all eyes (N=159). The average endothelial cell den-
sity diminished from 2339.9 ± 384.0 cells/mm2 before the
procedure to 2195.1 ± 437.5 cells/mm2 3 months after the
surgery (p<0.001). The median loss of corneal endothelial
cells was 4.6%, with an interquartile range (IQR) from 0
to 10.4%. Also, 22.1% (35 eyes) showed higher values of l
The data was entered into an Excel sheet (Microsoft
Excel, Microsoft Corporation, Redmond, WA, USA). STATA program (StataCorp, College Station, TX, USA)
was used for analysis. Each patient eye was given a code
to pseudonymize the data. Results The variables were analyzed by 1 3 1 3 Graefe's Archive for Clinical and Experimental Ophthalmology (2023) 261:3215–3221 3218 AL axial length, ACD anterior chamber depth, LT lens thickness, CDE cumulative dissipated energy
*median (interquartile range)
n
Mean ± SD
Age
159
67.4 ± 10.3
Sex
Male
75
47.1%
Female
84
52.8%
Eye
Right
80
50.3%
Left
79
49.6%
Cataract classification (LOCS III)
NO
159
2.7 ± 1.3
NC
159
2.6 ± 1.3
P*
159
0 (0–2)
C*
159
0 (0–1)
AL (mm)*
159
23.34 (22.46–23.98)
ACD (mm)
156
3.13 ± 0.41
LT (mm)
134
4.48 ± 0.42
Torsional amplitude time (seconds)*
154
16.2 (8.7–29.7)
Longitudinal power time (seconds)*
155
0 (0–0.1)
Total ultrasound time (seconds)*
155
16.4 (9.0–30.50)
Aspiration time (minutes)*
159
0.31 (0.25–0.37)
Total surgery time (minutes)*
155
11.50 (9.14–15.36)
CDE*
159
2.83 (1.59–5.99)
Estimated fluid usage (ml)*
159
133 (117–160) Table 1 Preoperative and
intraoperative parameters AL axial length, ACD anterior chamber depth, LT lens thickness, CDE cumulative dissipated energy
*median (interquartile range) endothelial cell density after surgery (range 0.03–12.5%). No patient had signs of a toxic anterior segment syndrome
(TASS) after cataract surgery. ECL. In addition, CDE was categorized in increases of
5 units, as follows: group 0 with CDE<5; group 1 with
CDE higher than 5 and lower or equal to 10; group 2 with
CDE higher than 10 and lower or equal to 15; and group 3
with CDE higher than 15. The difference of ECL in cases
with the same NC grade but with different CDE was 3.9%
(p<0.05) between group 0 and 1; 7.3% (p<0.05) between
group 0 and 2; and 15.0% between group 0 and 3. Endothelial cell density change analysis After univariate linear regression analysis, the following
variables were positively correlated with an increased risk
of ECL: age, NO and NC LOCSIII cataract classification,
torsional amplitude time, longitudinal power time, ultra-
sound total time, aspiration time, CDE, and estimated fluid
usage. After multivariate backwards analysis, NC grade
(beta coefficient 0.021, p=0.004) and CDE (beta coef-
ficient 0.005, p=0.016) were associated with increased Discussion The present study found the median ECL to be 4.6% (IQR
0% to10.4%), which is in the range of that reported in stud-
ies on phacoemulsification with intracameral antibiotics
(between 3.6% and 18.3%) (Table 3) [28, 31, 32]. The wide
range of ECL reported in the literature may be explained
by the fact that ECL is influenced by many different fac-
tors, including hardness of the cataract (in turn related to
the amount of ultrasonic energy applied), the technology
used during surgery (longitudinal phaco, torsional phaco,
previous division of the nucleus with manual instruments
or femtosecond laser, etc.), the experience of the surgeon, To our knowledge, there are no published articles
regarding the safety of intracameral Vigadexa® as
prophylaxis for POE after cataract surgery. Nonetheless,
Aguilera and Escaf have presented their results at the 2012
ESCRS meeting in Milan (Aguilera F, Escaf L. Evaluation
of ocular safety of prophylactic intracameral moxifloxacin-
dexamethasone combination in cataract surgery, ESCRS
Annual Congress 2012). Aguilera et al. showed that the
combination of moxifloxacin and dexamethasone was
safe, without anterior or posterior segment complications. Furthermore, they found that there was no statistical Table 3 Recent selected studies on postoperative corneal endothelial cell loss following phacoemulsification with intracameral antibiotics
ECD
d th li l
ll d
it
ECL
d th li l
ll l
Authors
# of eyes
Follow-up time after
surgery (weeks)
Intracameral
substance
Preoperative ECD
Postoperative ECD
Mean ECL (%)
Mean cells/mm2
SD
Mean cells/mm2
SD
Pérez-Canales et al. (2015) [31]
26
1
Vancomycin 1
mg/0.1 ml
2289.12
394.75
1957.1
443.48
14.5
Pérez-Canales et al. (2015) [31]
26
4
Vancomycin 1
mg/0.1 ml
2289.12
394.75
1952.27
395.74
14.7
Pérez-Canales et al. (2015) [31]
26
12
Vancomycin 1
mg/0.1 ml
2289.12
394.75
1984.58
417.25
13.3
Pérez-Canales et al. (2015) [31]
26
1
Cefuroxime 1
mg/0.1 ml
2441.31
350.64
2154.88
462.66
11.7
Pérez-Canales et al. (2015) [31]
26
4
Cefuroxime 1
mg/0.1 ml
2441.31
350.64
2121.35
443.84
13.1
Pérez-Canales et al. (2015) [31]
26
12
Cefuroxime 1
mg/0.1 ml
2441.31
350.64
2147.04
464.51
12.1
Lucena et al. (2018) [32]
1016
4
Moxifloxacin 150
μg/0.03 ml
2426
325
2177
283
10.3
Khalili et al. (2020) [33]
113
48
Moxifloxacin 250
μg/0.1 ml
3443
N/A
3320
N/A
3.6
Chang et al. (2020) [29]
25
4
Moxifloxacin 500
μg/0.1 ml
2700
N/A
2334
N/A
13.6
Chang et al. Percentage of ECL >10% After univariate logistic regression analysis, the following
variables were positively correlated with an increased risk
of ECL >10%: age, NO and NC grades, torsional amplitude Table 2 Endothelial cell density before and 3 months after surgery
*Wilcoxon sign rank test for difference between pre- and post-endothelial cell variables
†Non-normal distribution by Shapiro–Wilk test. Median (interquartile range)
‡Analysis was done with the full data set N=159
Preoperative
Postoperative
Change after surgery
p
Cell density (cells/mm2) ‡
2339 ± 384.09
2195.14 ± 437.54
−98.40 (−255–0) †
<0.001
Percentage of hexagonal cells (%)‡
51.65% ± 8.29%
49.60% ± 9.80%
−1% (−2–5%) †
0.001
Size (μm2) ‡
429.50 (393.10–485.60) †
450.20 (403.20–510.30) †
13.1 (0–33.5) †
<0.001
Coefficient of variation (%)‡
37.20% (34.40–41.30%) †
37.30% (34.50–41.10%) †
0 (1.7–2.2%) †
0.348 Table 2 Endothelial cell density before and 3 months after surgery 1 Graefe's Archive for Clinical and Experimental Ophthalmology (2023) 261:3215–3221 3219 and the surgical technique (divide and conquer, phaco chop,
double chop) [33–41]. time, longitudinal power time, ultrasound total time, aspira-
tion time, and CDE. After multivariate backwards analysis,
age (OR 1.04; p=0.014) and ultrasound total time in seconds
(OR 1.03; p=0.001) were associated with increased risk of
ECL >10%. The use of an intracameral substance (either an antibiotic
or an antibiotic plus steroid) is considered a potential factor
related to ECL. In this matter, this study analyzed the safety
of the use of intracameral Vigadexa® after cataract surgery
performed with only divide and conquer technique by
a single surgeon and showed no differences in ECL with
previously published literature (Table 3) [28, 31, 32, 42]. ECD endothelial cell density, ECL endothelial cell loss Discussion (2020) [29]
25
12
Moxifloxacin 500
μg/0.1 ml
2700
N/A
2387
N/A
11.6
Chang et al. (2020) [29]
25
4
Moxifloxacin 250
μg/0.1 ml
2721
N/A
2466
N/A
9.4
Chang et al. (2020) [29]
25
12
Moxifloxacin 250
μg/0.1 ml
2721
N/A
2496
N/A
8.3
Soro-Martínez et al. (2021) [34]
20
4
Cefuroxime
100μg/0.1 ml
2528
383
2066
434
18.3
Present study
159
12
Moxifloxacin 250
μg/0.05 ml +
Dexamethasone
50 μg/0.05 ml
2339
384
2195
437
6.2 1 3 1 3 3220 Graefe's Archive for Clinical and Experimental Ophthalmology (2023) 261:3215–3221 need to obtain permission directly from the copyright holder. To view a
copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. difference in ECL after cataract surgery either with the use
of Vigadexa® or (balanced saline solution) BSS. need to obtain permission directly from the copyright holder. To view a
copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. On another note, the present study found that for every
increase in CDE of 1 unit, there was a 0.5% increase in ECL. Additionally, the percentage of ECL doubled with every 5-unit
increase in CDE. ECL >10% was associated with age and
total ultrasound time during surgery. Mahdy et al. also found
a positive correlation between CDE and total ultrasound time
with ECL [33]. Declarations 10. Yuan Q, Liu Y, Gou Y et al (2022) Efficacy and safety of the dexa-
methasone implant in vitrectomized and nonvitrectomized eyes with
diabetic macular edema: a systematic review and meta-analysis. Front Pharmacol 13:1029584. https://doi.org/10.3389/fphar.2022.
1029584 Ethics approval and consent to participate The study was approved
by the IRB at Fundación Oftalmologica de Santander FOSCAL. All
procedures performed involving human participants were in accord-
ance with the ethical standards at FOSCAL Clinic and with the 1964
Helsinki Declaration and its later amendments or comparable ethical
standards. All patients gave written consent for the use of their clinical
data for research and publication purposes. 11. Raina UK, Ravinesh K, Bhattacharya S et al (2023) Comparison
of topical steroids versus adjunctive intracameral triamcinolone
versus posterior subtenon triamcinolone in pediatric cataract
surgery. Indian J Ophthalmol 71:119–123 12. Lindholm J-M, Taipale C, Ylinen P, Tuuminen R (2020) Periopera-
tive subconjunctival triamcinolone acetonide injection for preven-
tion of inflammation and macular oedema after cataract surgery. Acta Ophthalmol 98:36–42. https://doi.org/10.1111/aos.14175fi References J Cataract Refract
Surg 45:343–350. https://doi.org/10.1016/j.jcrs.2018.10.044 g
p
g
j j
6. Chang DF, Rhee DJ (2022) Antibiotic prophylaxis of postopera-
tive endophthalmitis after cataract surgery: results of the 2021
ASCRS member survey. J Cataract Refract Surg 48:3–7. https://
doi.org/10.1097/j.jcrs.0000000000000757 g
p
g
j j
6. Chang DF, Rhee DJ (2022) Antibiotic prophylaxis of postopera-
tive endophthalmitis after cataract surgery: results of the 2021
ASCRS member survey. J Cataract Refract Surg 48:3–7. https://
doi.org/10.1097/j.jcrs.0000000000000757 In conclusion, in the present study, the intracameral injec-
tion of a preservative-free combination of moxifloxacin and
dexamethasone (Vigadexa®) at the end of cataract surgery
did not show deleterious effects on the corneal endothelium
at 3 months. Further studies are warranted to confirm the pos-
sible anti-inflammatory effects of intracameral dexamethasone
in the early postoperative period after cataract surgery. Also,
future studies should include a control group with the use of
only an intracameral antibiotic. g
j j
7. Barry P, Cordovés L, Gardner S ESCRS guidelines for prevention
and treatment of endophthalmitis following cataract surgery: data,
dilemmas and conclusions 2013. https://www.escrs.org/media/
uljgvpn1/english_2018_updated.pdf. Accessed 24 Jan 2023 g
j j
7. Barry P, Cordovés L, Gardner S ESCRS guidelines for prevention
and treatment of endophthalmitis following cataract surgery: data,
dilemmas and conclusions 2013. https://www.escrs.org/media/
uljgvpn1/english_2018_updated.pdf. Accessed 24 Jan 2023 jg p
g
p
p
8. Bowen RC, Zhou AX, Bondalapati S et al (2018) Comparative
analysis of the safety and efficacy of intracameral cefuroxime,
moxifloxacin and vancomycin at the end of cataract surgery: a
meta-analysis. Br J Ophthalmol 102:1268–1276. https://doi.org/
10.1136/BJOPHTHALMOL-2017-311051f 8. Bowen RC, Zhou AX, Bondalapati S et al (2018) Comparative
analysis of the safety and efficacy of intracameral cefuroxime,
moxifloxacin and vancomycin at the end of cataract surgery: a
meta-analysis. Br J Ophthalmol 102:1268–1276. https://doi.org/
10.1136/BJOPHTHALMOL-2017-311051f 9. Sun L, Huang L, Li S et al (2023) Safety and effectiveness
of intravitreal dexamethasone implant in patients with ocular
toxocariasis. Br J Ophthalmol 2022:322244. https://doi.org/10.
1136/bjo-2022-322244 References 1. WHO: Blindness and vision impairment. https://www.who.int/
en/news-room/fact-sheets/detail/blindness-and-visual-impai
rment. Accessed 24 Jan 2023 2. Batlle JF, Lansingh VC, Silva JC et al (2014) The cataract situa-
tion in Latin America: barriers to cataract surgery. Am J Ophthal-
mol 158:242–250.e1. https://doi.org/10.1016/j.ajo.2014.04.019 Regarding the assessment of HCEC, non-contact specular
microscope has been shown to be a reliable method [43]. In
a Colombian cohort, the mean difference of endothelial cell
density repeated measurements was 8.3 ± 168.9 cell/mm2 (i.e.,
0.3% ± 6.1%) and 95% limits of agreement from −322.6 to
339.5 (i.e., −11.7% to 12.3%) [44]. The variability in repeated
measurements may explain the increase in endothelial cell
density in 22.1% eyes in the present study. Regarding the assessment of HCEC, non-contact specular
microscope has been shown to be a reliable method [43]. In
a Colombian cohort, the mean difference of endothelial cell
density repeated measurements was 8.3 ± 168.9 cell/mm2 (i.e.,
0.3% ± 6.1%) and 95% limits of agreement from −322.6 to
339.5 (i.e., −11.7% to 12.3%) [44]. The variability in repeated
measurements may explain the increase in endothelial cell
density in 22.1% eyes in the present study. p
g
j j
3. Rangel CM et al (2022) Endophthalmitis in ophthalmological
referral centre in Colombia: aetiology and microbial resistance. Ces a Slov Oftalmol Cas Ces Oftalmol Spol a Slov Oftalmol
Spol 78:160–173. https://doi.org/10.31348/2022/19 p
g
j j
3. Rangel CM et al (2022) Endophthalmitis in ophthalmological
referral centre in Colombia: aetiology and microbial resistance. Ces a Slov Oftalmol Cas Ces Oftalmol Spol a Slov Oftalmol
Spol 78:160–173. https://doi.org/10.31348/2022/19 p
p
g
4. Barry P, Gettinby G, Lees F et al (2007) Prophylaxis of postop-
erative endophthalmitis following cataract surgery: results of
the ESCRS multicenter study and identification of risk factors. J Cataract Refract Surg 33:978–988. https://doi.org/10.1016/J.
JCRS.2007.02.032 The limitations of the present study include the absence of
a control group and the assessment of HCEC with only one
image from the non-contact specular microscope, which could
be related to the result of a no plausible increase of endothelial
cell density in 22.1% of cases. 5. Melega MV, Alves M, Lira RPC et al (2019) Safety and efficacy of
intracameral moxifloxacin for prevention of post-cataract endoph-
thalmitis: randomized controlled clinical trial. J Cataract Refract
Surg 45:343–350. https://doi.org/10.1016/j.jcrs.2018.10.044 5. Melega MV, Alves M, Lira RPC et al (2019) Safety and efficacy of
intracameral moxifloxacin for prevention of post-cataract endoph-
thalmitis: randomized controlled clinical trial. Conflict of interest The authors declare no competing interests. Open Access This article is licensed under a Creative Commons Attri-
bution 4.0 International License, which permits use, sharing, adapta-
tion, distribution and reproduction in any medium or format, as long
as you give appropriate credit to the original author(s) and the source,
provide a link to the Creative Commons licence, and indicate if changes
were made. The images or other third party material in this article are
included in the article's Creative Commons licence, unless indicated
otherwise in a credit line to the material. If material is not included in
the article's Creative Commons licence and your intended use is not
permitted by statutory regulation or exceeds the permitted use, you will 13. Kindle T, Ferguson T, Ibach M et al (2018) Safety and efficacy of
intravitreal injection of steroid and antibiotics in the setting of cata-
ract surgery and trabecular microbypass stent. J Cataract Refract
Surg 44:56–62. https://doi.org/10.1016/J.JCRS.2017.10.040 14. Tyson SL, Bailey R, Roman JS et al (2017) Clinical outcomes
after injection of a compounded pharmaceutical for prophylaxis
after cataract surgery: a large-scale review. Curr Opin Ophthal-
mol 28:73–80. https://doi.org/10.1097/ICU.0000000000000329 15. Gungor SG, Bulam B, Akman A, Colak M (2014) Comparison
of intracameral dexamethasone and intracameral triamcinolone 1 3 3221 Graefe's Archive for Clinical and Experimental Ophthalmology (2023) 261:3215–3221 acetonide injection at the end of phacoemulsification surgery. Indian J
Ophthalmol 62:861–864. https://doi.org/10.4103/0301-4738.141045 31. Lucena ND, Pereira IM, Gaete MI et al (2018) Intracameral mox-
ifloxacin after cataract surgery: a prospective study. Arq Bras
Oftalmol 81:92–94. https://doi.org/10.5935/0004-2749.20180022 p
p
g
16. Pareja-Ríos A, Ruiz-de la Fuente-Rodríguez P, Bonaque-González
S et al (2018) Intravitreal dexamethasone implants for diabetic
macular edema. Int J Ophthalmol 11:77–82. https://doi.org/10.
18240/ijo.2018.01.14 32. Soro-Martínez MI, Miralles de Imperial-Ollero JA, Pastor-Montoro
M et al (2021) Corneal endothelial cell loss after trabeculectomy and
phacoemulsification in one or two steps: a prospective study. Eye
(Lond) 35:2999–3006. https://doi.org/10.1038/s41433-020-01331-x j
17. Galvis V, Tello A, Gutierrez ÁJ (2013) Human corneal endothe-
lium regeneration: effect of ROCK inhibitor. Invest Ophthalmol
Vis Sci 54:4971–4973 33. Mahdy MAES, Eid MZ, Mohammed MA-B, et al (2012) Relation-
ship between endothelial cell loss and microcoaxial phacoemul-
sification parameters in noncomplicated cataract surgery. Clin
Ophthalmol 6:503–10i 18. Galvis V, Tello A, Gomez AJ et al (2013) Corneal transplantation
at an ophthalmological referral center in Colombia: indications
and techniques (2004-2011). Open Ophthalmol J 7:30–33. https://
doi.org/10.2174/1874364101307010030 p
34. Conflict of interest The authors declare no competing interests. Ammous I, Bouayed E, Mabrouk S et al (2017) Phacoemulsifica-
tion versus manual small incision cataract surgery: anatomic and
functional results. J Fr Ophtalmol 40:460–466. https://doi.org/10.
1016/j.jfo.2017.02.005fi g
19. Gain P, Jullienne R, He Z et al (2016) Global survey of corneal
transplantation and eye banking. JAMA Ophthalmol 134:167–
173. https://doi.org/10.1001/jamaophthalmol.2015.4776 35. Taşkın İ, Aslan L (2018) Effects of phacoemulsification with ver-
sus without viscoelastic devices on surgical outcomes. Int Oph-
thalmol 38:5–10. https://doi.org/10.1007/s10792-017-0546-y 20. Galvis V, Tello A, Laiton AN, Salcedo SLL (2019) Indications and
techniques of corneal transplantation in a referral center in Colom-
bia, South America (2012-2016). Int Ophthalmol 39:1723–1733. https://doi.org/10.1007/s10792-018-0994-z 36. Perone JM, Boiche M, Lhuillier L et al (2018) Correlation
between postoperative central corneal thickness and endothelial
damage after cataract surgery by phacoemulsification. Cornea. https://doi.org/10.1097/ICO.0000000000001502f p
g
21. Avisar R, Weinberger D (2010) Corneal endothelial morphologic
features in toxic anterior segment syndrome. Cornea 29:251–253. https://doi.org/10.1097/ICO.0b013e3181b11568 37. Khokhar S, Aron N, Sen S et al (2017) Effect of balanced phacoe-
mulsification tip on the outcomes of torsional phacoemulsification
using an active-fluidics system. J Cataract Refract Surg 43:22–28. https://doi.org/10.1016/j.jcrs.2016.11.034 22. Tan RR, Tumbocon JA, Lim R et al (2015) Safety of intracameral
moxifloxacin/ dexamethasone fixed-dose formulation on the corneal
endothelium in a rabbit model. Philipp J Ophthalmol 40:24–28 pp
p
23. Kernt M, Neubauer AS, Liegl RG et al (2009) Intracameral moxi-
floxacin: in vitro safety on human ocular cells. Cornea 28:553–
561. https://doi.org/10.1097/ICO.0b013e318191447b 38. Al-Mohtaseb Z, He X, Yesilirmak N et al (2017) Comparison of
corneal endothelial cell loss between two femtosecond laser plat-
forms and standard phacoemulsification. J Refract Surg 33:708–
712. https://doi.org/10.3928/1081597X-20170731-01 24. Kernt M, Hirneiss C, Neubauer AS et al (2010) Intracameral
moxifloxacin: a safe option for endophthalmitis prophylaxis? In vitro safety profile for intraocular application. Ophthalmologe
107:720–727. https://doi.org/10.1007/s00347-009-2027-9 39. He X, Diakonis VF, Alavi Y et al (2017) Endothelial cell loss
in diabetic and nondiabetic eyes after cataract surgery. Cornea
36:948–951. https://doi.org/10.1097/ICO.0000000000001245 40. Chen H, Lin H, Chen W et al (2016) Femtosecond laser com-
bined with non-chopping rotation phacoemulsification technique
for soft-nucleus cataract surgery: a prospective study. Sci Rep
6:18684. https://doi.org/10.1038/srep18684 25. Park J-H, Kim M, Chuck RS, Park CY (2021) Evaluation of mox-
ifloxacin-induced cytotoxicity on human corneal endothelial cells. Sci Rep 11:6250. https://doi.org/10.1038/s41598-021-85834-xfi 26. Haripriya A, Chang DF, Namburar S et al (2016) Efficacy of intra-
cameral moxifloxacin endophthalmitis prophylaxis at Aravind Eye
Hospital. Ophthalmology 123:302–308. https://doi.org/10.1016/j.
ophtha.2015.09.037 41. Conflict of interest The authors declare no competing interests. Chen X, Yu Y, Song X et al (2017) Clinical outcomes of femto-
second laser-assisted cataract surgery versus conventional phacoe-
mulsification surgery for hard nuclear cataracts. J Cataract Refract
Surg 43:486–491. https://doi.org/10.1016/j.jcrs.2017.01.010 p
27. Ekinci Koktekir B, Aslan BS (2012) Safety of prophylactic intra-
cameral moxifloxacin use in cataract surgery. J Ocul Pharmacol
Ther Off J Assoc Ocul Pharmacol Ther 28:278–282. https://doi.
org/10.1089/jop.2011.0132 42. Khalili S, Imtirat A, Williams S et al (2020) Safety of intracameral
moxifloxacin in the pediatric population: an equivalence study. J Cataract Refract Surg 46:228–234. https://doi.org/10.1097/J.
JCRS.0000000000000018 28. Chang DF, Prajna NV, Szczotka-Flynn LB et al (2020) Compara-
tive corneal endothelial cell toxicity of differing intracameral moxi-
floxacin doses after phacoemulsification. J Cataract Refract Surg
46:355–359. https://doi.org/10.1097/J.JCRS.0000000000000064 43. Ding X, Huang Q, Zheng Y et al (2012) Measurement area and
repeatability of semiautomated assessment of corneal endothelium
in the Topcon specular microscope SP-2000P and IMAGEnet sys-
tem. Cornea 31:1111–1118. https://doi.org/10.1097/ICO.0b013
e31820e42b5 29. Chylack LTJ, Wolfe JK, Singer DM et al (1993) The Lens Opaci-
ties Classification System III. The Longitudinal Study of Cataract
Study Group. Arch Ophthalmol (Chicago, Ill 1960) 111:831–836 44. Galvis V, Tello A, Rodríguez L, Chaparro T (2011) Resultados del
análisis endotelial con el microscopio especular de no contacto
Topcon SP-3000P ®. Rev Soc Colomb Oftalmol 44:253–260 30. Yee RW, Matsuda M, Schultz RO, Edelhauser HF (1985) Changes
in the normal corneal endothelial cellular pattern as a function of
age. Curr Eye Res 4:671–678 Publisher’s note Springer Nature remains neutral with regard to
jurisdictional claims in published maps and institutional affiliations. 1 3 1 3
|
https://openalex.org/W4382560773
|
https://www.businessperspectives.org/images/pdf/applications/publishing/templates/article/assets/18395/IM_2023_02_Livas.pdf
|
English
| null |
Consumer sentiment toward international activist advertising
|
Innovative marketing
| 2,023
|
cc-by
| 7,387
|
Consumer sentiment toward international activist advertising” Consumer sentiment toward international activist advertising” businessperspectives.org “Consumer sentiment toward international activist advertising” AUTHORS
Christos Livas
Faidon Theofanidis
Nansy Karali
ARTICLE INFO
Christos Livas, Faidon Theofanidis and Nansy Karali (2023). Consumer
sentiment toward international activist advertising. Innovative Marketing , 19(2),
250-260. doi:10.21511/im.19(2).2023.20
DOI
http://dx.doi.org/10.21511/im.19(2).2023.20
RELEASED ON
Thursday, 29 June 2023
RECEIVED ON
Tuesday, 14 March 2023
ACCEPTED ON
Tuesday, 20 June 2023
LICENSE
This work is licensed under a Creative Commons Attribution 4.0 International
License
JOURNAL
"Innovative Marketing "
ISSN PRINT
1814-2427
ISSN ONLINE
1816-6326
PUBLISHER
LLC “Consulting Publishing Company “Business Perspectives”
FOUNDER
LLC “Consulting Publishing Company “Business Perspectives”
NUMBER OF REFERENCES
41
NUMBER OF FIGURES
2
NUMBER OF TABLES
3
© The author(s) 2023. This publication is an open access article. © The author(s) 2023. This publication is an open access article. businessperspectives.org businessperspectives.org Innovative Marketing, Volume 19, Issue 2, 2023 Christos Livas (Greece), Faidon Theofanidis (Kuwait), Nansy Karali (Greece) Received on: 14th of March, 2023
Accepted on: 20th of June, 2023
Published on: 29th of June, 2023 Christos Livas, Assistant Professor of
Marketing, Department of Business
Administration, School of Economics
and Business, University of Patras,
Greece. (Сorresponding author) Nansy Karali, Adjunct Lecturer of
Entrepreneurship, Department of
Economics, School of Economics,
Business and International Studies,
University of Piraeus, Greece. Keywords Faidon Theofanidis, Associate Professor
of Marketing, Marketing Department,
College of Business, Australian
University, Kuwait. JEL Classification
M16, M31, M37 JEL Classification
M16, M31, M37 JEL Classification
M16, M31, M37 Nansy Karali, Adjunct Lecturer of
Entrepreneurship, Department of
Economics, School of Economics,
Business and International Studies,
University of Piraeus, Greece. BUSINESS PERSPECTIVES www.businessperspectives.org
LLC “СPС “Business Perspectives”
Hryhorii Skovoroda lane, 10,
Sumy, 40022, Ukraine © Christos Livas, Faidon Theofanidis,
Nansy Karali, 2023 Abstract Companies have been increasingly conveying activist advertising messages to interna-
tional audiences in response to persisting social ills and unsustainable business practic-
es. Given the ambiguity surrounding the effects of international advertising, this study
aims to compare the response of local consumers to a multinational brand’s standard-
ized activist advertising strategy with creative executions adapted to the national con-
texts of Greece and the USA. The selected brand originates from the USA. The paper
used a systematic qualitative approach and sentiment analysis using Microsoft Excel
and Azure Machine Learning add-in. Analysis conducted on 1,051 user comments in
January 2023 regarding two publicly accessible social media posts of a multinational
haircare brand showed both similarities and differences in consumer responses. 662
comments were in English and 389 comments were in Greek. The study’s dataset
was anonymized entirely and de-identified. The results indicate that consumer senti-
ment was largely negative in both countries. Although the relative share of negative
comments was significantly higher in the USA (96.7%) than in Greece (59.4%), both
groups of consumers placed their emphasis on the same themes (e.g., children and
products). Therefore, they have perceived the main message similarly, irrespective of
the execution differences. Overall, the findings can be attributed to strategic and tacti-
cal issues of the activist advertising campaign, as well as to sociocultural particularities
of the national context. In the case of international advertising, attempts to incorporate
the brand’s stance on a controversial sociopolitical issue into its advertising strategy
pose significant risks to business organizations. © Christos Livas, Faidon Theofanidis,
Nansy Karali, 2023 brand activism, multinational brand, local consumers,
sentiment analysis, social media, Greece, USA brand activism, multinational brand, local consumers,
sentiment analysis, social media, Greece, USA This is an Open Access article,
distributed under the terms of the
Creative Commons Attribution 4.0
International license, which permits
unrestricted re-use, distribution, and
reproduction in any medium, provided
the original work is properly cited.
Conflict of interest statement:
Author(s) reported no conflict of interest 1. LITERATURE REVIEW mistakes (Kale, 1991). Overall, the adaptation per-
spective emphasizes the need to relate to local cus-
tomer characteristics, needs, desires, and customs
and is particularly effective in societies with low
openness to foreign markets (Rajabi et al., 2017). Since the 1960s, a substantial part of interna-
tional advertising literature has concentrated
on the advertising standardization vs. adapta-
tion dispute. Decisions such as whether, to what
extent, when, and how advertising should adapt
to different countries have emerged as primary
considerations for academics and practition-
ers. Factors such as increasing similarities in
living conditions, consumer homogenization,
and market globalization (Elinder, 1965; Levitt,
1983) were initially viewed as the main drivers of
advertising standardization across international
markets. Standardization of advertising output
has been associated with potential cost advan-
tages for business organizations (Moriarty &
Duncan, 1991) and an increased ability to shape
a consistent brand image across national bor-
ders (Duncan & Ramaprasad, 1995). Although
complete standardization of advertising has
been viewed as a rather rare marketing strategy
(Harris, 1994), it is believed to be effective in so-
cioeconomically and culturally similar national
contexts (Sriram & Gopalakrishna, 1991). This
approach is seemingly compatible with integrat-
ed marketing communications, which dictates
that the marketing message delivered through
diverse channels and marketing communication
types should be consistent (Finne & Grönroos,
2009). Given the advertising standardization ap-
proach, the need to convey uniform messages
extends to the international setting. A slight deviation from these positions posits
that the distance between standardization and
adaptation should be viewed as a continuum
rather than a dichotomy (Moriarty & Duncan,
1991; Papavassiliou & Stathakopoulos, 1997;
Vrontis & Thrassou, 2007). These contingency
perspectives suggest that there should be a dis-
tinction between advertising strategy and exe-
cution in terms of advertising standardization
(James & Hill, 1991; Moriarty & Duncan, 1991;
Taylor & Johnson, 2002) and that international
advertising adaptation depends on situational
factors such as demographics, level of economic
development, language, and heritage (Onkvisit
& Shaw, 1999). Instead of absolute adherence
to one of the two extremes, most multinational
brands adopt an approach in which the adver-
tising strategy is standardized, but the adver-
tising execution is localized (Taylor & Johnson,
2002). INTRODUCTION The traditional marketing philosophy suggests that brands ought to
be market-oriented and adjust their marketing strategies and tactics
to their target segments’ characteristics and preferences. However,
this market-driven philosophy is challenged by persisting global
issues, such as climate change and socioeconomic injustice (Sheth
& Parvatiyar, 2021). In response to social ills and unsustainable
production and consumption models, Sheth and Parvatiyar (2021)
have advocated the adoption of a market-driving philosophy, which
guides the introduction of pro-social engineering interventions
(Kennedy & Parsons, 2012). In this context, and considering exist-
ing sociopolitical turbulence, companies have increasingly engaged
in various forms of brand activism (Moorman, 2020). Although
brand activism is not limited to marketing communications, brands
frequently incorporate aspects of their stance on social issues into
their advertising strategy (Livas, 2021). These societal or activist ad-
vertising messages have generated mixed consumer responses, and
their effectiveness in promoting organizational objectives and posi-
tive social change is uncertain (Livas, 2021). 250 http://dx.doi.org/10.21511/im.19(2).2023.20 Innovative Marketing, Volume 19, Issue 2, 2023 http://dx.doi.org/10.21511/im.19(2).2023.20 1. LITERATURE REVIEW Thus, standardization of international adver-
tising strategies may often involve associating the
brand with the same or similar sociopolitical is-
sues across different national contexts with poten-
tially diverse social value systems. vertising adaptation presuppose that advertising
lacks control over the existing social value system,
which it must adjust. Analogous to the standardization vs. adaptation
dispute and the emergence of contingency per-
spectives, it is possible to identify a range of view-
points between the value manipulation vs. reflec-
tion dichotomy. For instance, Mueller (1986) ar-
gued that advertising reflects specific social val-
ues deemed commercially profitable but lacks the
power to manipulate them, as it operates in paral-
lel with other influential and value-shaping insti-
tutions (Aaker & Myers, 1975). However, although
advertising may not have the power to alter exist-
ing social values directly or to a great extent, it has
control over which values to emphasize from the
preexisting system to be both relevant and prof-
itable (Livas, 2021). Despite the observed simi-
larities between the standardization vs. adapta-
tion and manipulation vs. reflection dichotomies,
activist advertising poses certain peculiarities. Associating the brand with sociopolitical issues
is a strategic decision. When it is done at a global
level and in order to be effective, it presupposes:
(1) that the majority of (target) consumers across
different national and sociocultural contexts are
in agreement with the brand’s stance on contro-
versial sociopolitical issues, or (2) that the brand
can exert substantial influence on consumers who
originally adopted a different stance. The broader advertising literature has a similar
debate over the standardization vs. adaptation
dispute. Although advertising has been acknowl-
edged to relate to sociocultural values, the direc-
tion of this relationship has yet to be universally
agreed upon. For instance, Pollay (1983, 1986)
and Pollay and Gallagher (1990) have argued that
advertising can shape social values. Pollay and
Gallagher (1990) often accused it of perpetuating
several social ills, such as excessive consumption,
materialism, and sexism. From this perspective,
Mueller’s (1986) concerns about the potential crea-
tion of universal consumers, assisted by the exten-
sive use of standardized advertising practices, also
attribute substantial sociocultural power to global
advertising. If advertising message standardiza-
tion is associated with deliberately overlooking
existing sociocultural differences among nation-
al markets, it assumes at least partial control over
the social value system. 1. LITERATURE REVIEW With some exceptions (Hatzithomas et
al., 2016), most international advertisers follow a
standardized strategy with modified executions
in which brand positioning, main message ap-
peals, and unique selling propositions remain
the same (Moriarty & Duncan, 1991; Zandpour
& Harich, 1996). However, decisions related to
the method of message presentation are adapt-
ed to match the particularities of the local
markets. For instance, multinational brands,
which acknowledge that national markets in
the European Union are converging, are more
likely to increase advertising standardization of
certain strategic elements to create a consistent
brand image, target cross-market segments, and
achieve cost advantages (Okazaki et al., 2007). In contrast, some tactical message elements,
such as the language used in the advertisements,
may be dubbed or subtitled (Pagani et al., 2015). Irrespective of the actual international market-
ing philosophy being employed, to achieve supe-
rior performance, the marketing or advertising
strategy should match the external circumstanc-
es faced by the brand (Theodosiou & Leonidou,
2003) and thus achieve a fit between strategy and
context (Schmid & Kotulla, 2011). A second school of thought posits that advertis-
ers ought to consider several significant barriers
to advertising standardization (Douglas & Wind,
1987; Miracle et al., 1992), which are largely relat-
ed to existing and sometimes widening consum-
er differences (De Mooij, 2003; Onkvisit & Shaw,
1999; Penz & Stöttinger, 2015). Such differenc-
es in consumer characteristics are thought to be
evinced by the variation in the use of advertising
elements and the adoption of diverse message
strategies among numerous countries with seem-
ingly similar cultures (Caillat & Mueller, 1996). Consequently, this literature stream suggests that
advertising messages should be adapted to the na-
tional context within which they are displayed. In
this way, brands can reduce the likelihood of mis-
interpretation, leading to significant marketing 251 Innovative Marketing, Volume 19, Issue 2, 2023 To date, advertising literature has predominately
focused on the standardization and/or adaptation
of typical international advertising, which usual-
ly delivers commercial messages about companies
and product offerings. Nevertheless, because sev-
eral contemporary brands consistently incorpo-
rate their views on controversial sociopolitical is-
sues into their advertising campaigns (Moorman,
2020), their sociopolitical stance becomes a strate-
gic aspect of their marketing and advertising strat-
egy. 2. METHODS The study employed a systematic qualitative ap-
proach to examine consumer sentiment toward
international brand activism. More specifically,
sentiment analysis was performed to investigate
how consumers responded to two activist adver-
tising messages using Microsoft Excel and Azure
Machine Learning add-in. From a procedural point
of view, the textual data obtained (i.e., social media
users’ comments) were initially automatically cat-
egorized as positive or negative using the machine
learning tool. Apart from classifying user com-
ments, the machine learning tool produced a score,
with values closer to zero indicating a negative sen-
timent and values closer to one indicating a positive
sentiment. Given that the automated classification
may misinterpret textual data in certain circum-
stances (e.g., use of irony and/or jargon), the result-
ing categorizations were evaluated and corrected
where necessary. In these situations, the original
score automatically produced by the add-in was de-
leted because it was meaningless (i.e., the original
classification was altered). Apart from social networks, activist advertising mes-
sages were also delivered through mass media in
Greece and the USA and employed the same strategy
that focused on associating the brand with LGBTQI+
empowerment and visibility enhancement. In line
with common advertising practices across interna-
tional markets (Taylor & Johnson, 2002), advertising
execution was slightly different. Apart from using the
Greek language, the activist message of the campaign
launched in early 2022 in Greece portrayed stories of
characters belonging to the LGBTQI+ community
and attempted to establish an association with the
brand’s products. The activist campaign launched
in early 2021 in the USA was delivered in English
language and focused on the story of an LGBTQI+
household. This message also connected individuals’
identities and the brand’s products. Given the comparative approach of this study, prior
literature has indicated specific cultural differences
between Greece and the USA. For instance, Greek
society has been found to emphasize sincerity, re-
sponsibility, patriotism/ethnic pride, and spiritual-
ity, while Americans focus primarily on self-worth,
individuality, and compassion (Tamis-LeMonda et
al., 2002). Rodman (1967) found that Greek families
tend to be more patriarchal than American families,
which are viewed as being more egalitarian. Thus, al-
though both countries belong to the Western world,
consumers in the two nations are likely to be cultur-
ally diverse and therefore differ in their responses to
activist advertising messages. The two countries selected for this study were the
USA and Greece. 1. LITERATURE REVIEW Previous literature notes the ambiguity surround-
ing international advertising, which is often as-
sumed to depend on multinational brands’ unique
circumstances (Theodosiou & Leonidou, 2003),
and the contemporary notion of brand activism. Thus, this study seeks to provide primarily quali-
tative empirical evidence regarding local consum-
ers’ sentiment toward a contemporary interna-
tional activist campaign characterized by stand-
ardized advertising strategy and creative execu-
tions adapted to the national contexts of Greece
and the USA. Overall, this analysis is driven by
the scarcity of empirical evidence on the impact
of activist advertising on consumer sentiment in
both national and international settings. In contrast, other academics and advertising prac-
titioners have posited that marketing messages
merely reflect social values and mores, as they
lack the power to influence them (Holbrook, 1987;
Ogilvy, 1985). Following this perspective, for ad-
vertising to persevere, it filters conflicting incom-
ing values from abroad to preserve societal har-
mony (Petit & Zakon, 1962). Because fundamen-
tal marketing principles dictate that marketing
ought to acknowledge and adapt to market differ-
ences, the effectiveness of marketing communi-
cation often depends on the design and delivery
of diverse advertising messages (Holbrook, 1987). Consequently, proponents of international ad- Following the literature review, the purpose of
this study is to investigate the response of local
consumers to a multinational brand’s standard- 252 http://dx.doi.org/10.21511/im.19(2).2023.20 http://dx.doi.org/10.21511/im.19(2).2023.20 Innovative Marketing, Volume 19, Issue 2, 2023 Middle East. The Greek civilization formed a legacy
with unparalleled influence on Western civilization. Therefore, the USA and Greece serve the attempted
comparison in consumer sentiment as they are two
diverse sociocultural countries, but historically with
significant political interaction and reciprocal social
and cultural influences. Nowadays, despite their dif-
ferences and similarities, Greece is on the receiving
end of sociocultural trends and advertising practic-
es from the USA. ized activist advertising strategy with adapted (i.e.,
localized) creative executions. The focus on the re-
lationship between the national context and brand
activism is expected to reveal the readiness of con-
sumers across international markets to support
the promotion and association of the exact social
cause with the brand. http://dx.doi.org/10.21511/im.19(2).2023.20 3. RESULTS The examination of the relationship between the
national context of the activism campaign and
the type of consumer sentiment it elicited (Table
1) suggests the existence of a statistically signifi-
cant (χ2 = 240.099, p < 0.001) and substantial as-
sociation (Cramer’s V = 0.478, p < 0.001). 40.6%
of social media users’ comments about the brand
activism campaign launched in Greece were pos-
itive, and 59.4% were negative. For the brand ac-
tivism campaign launched in the USA, only 3.3%
of the comments were positive, while 96.7% were
negative. Although most comments conveyed
negative sentiments in both countries, the rela-
tive share of negative comments was significantly
higher in the USA. 1. Strictly textual data were manually retrieved
from the comment section of the two posts. Thus, the resulting dataset included the text of
the social media users’ comments, the number
of likes and responses to each comment at the
time of data collection (i.e., January 2023), the
national context of the brand’s post (i.e., the
USA or Greece), the type of sentiment (i.e., posi-
tive or negative), and the sentiment score attrib-
uted to each comment (i.e., ranging from zero
to one). Although manual extraction of com-
ments was time-consuming, ensuring compli-
ance with data scraping restrictions was neces-
sary. Furthermore, the collection of textual data
resulted in a wholly anonymous and de-identi-
fied dataset, which formed the basis for all sub-
sequent analyses. 1. Strictly textual data were manually retrieved
from the comment section of the two posts. Thus, the resulting dataset included the text of
the social media users’ comments, the number
of likes and responses to each comment at the
time of data collection (i.e., January 2023), the
national context of the brand’s post (i.e., the
USA or Greece), the type of sentiment (i.e., posi-
tive or negative), and the sentiment score attrib-
uted to each comment (i.e., ranging from zero
to one). Although manual extraction of com-
ments was time-consuming, ensuring compli-
ance with data scraping restrictions was neces-
sary. Furthermore, the collection of textual data
resulted in a wholly anonymous and de-identi-
fied dataset, which formed the basis for all sub-
sequent analyses. Table 1. Activism campaign and type
of sentiment Table 1. 2. METHODS At this point, the selected brand
originates from the USA. Thus, including the brand’s
activist advertising message in its home country
(the USA) was a benchmark for its overseas activ-
ist advertising campaign (Greece). Furthermore,
the contribution of the USA to marketing science is
arguably evinced by the constant and frequent dis-
semination of marketing and advertising practic-
es from the USA to other regions of the world, in-
cluding Europe. Greece was selected as an overseas
European market, in which the American brand
used practically the same international advertising
strategy but with a localized execution. Apart from
allowing comparisons with the USA, Greece repre-
sents a unique sociocultural context that combines
aspects of Western Europe, Eastern Europe, and the The study sample consisted of 1,051 social media
comments on two posts of a multinational brand
competing in the haircare industry publicly accessi-
ble (i.e., the two posts did not require registration to
the network’s services to be accessed). Each post was
displayed on the multinational brand’s official and
publicly accessible social network pages for social 253 Innovative Marketing, Volume 19, Issue 2, 2023 media users in Greece and the USA and contained
a short video advertisement (one in Greek and one
in English). Of the total comments obtained (1,051),
662 were in English. They referred to the American
(the USA) social media post, while the remaining
389 comments were in Greek and had to be trans-
lated before data analysis. User comments were col-
lected manually because the social network’s terms
and conditions do not allow data collection using
automatic means (e.g., data scraping). The manu-
al approach ensured that the study obtained on-
ly textual data and excluded personal information
(e.g., usernames, names, and surnames). Thus, the
study’s dataset was completely anonymized and
de-identified. Overall, to ensure adherence to the
GDPR regulations (i.e., Regulation (EU) 2016/679),
compliance with the social networking medium’s
terms, and protection of the rights and well-being
of social media users, this study introduced the fol-
lowing measures: For the same purpose, none of the phrases or sen-
tences used in the comments were reported, and
the study included aggregate statistics, sentiment
analysis (positive vs. negative), and identifying the
most frequently occurring words in positive and
negative comments. 2. METHODS Although it is expected that the
research design and protective measures introduced
hinder the replicability of this analysis, they were
established to meet existing regulations and ethical
standards to protect the rights, privacy, and well-be-
ing of individuals. 3. RESULTS These negatively pre-
disposed social media users also appeared to pro-
test the campaign by threatening to withdraw from
commercial or social relationships with the brand. Regarding the positive comments, the words most
frequently mentioned were “well, done, congratula-
tions, children, ad, wonderful, perfect, homophobes,
and conservatives.” Thus, such users were receptive
to the brand’s message and encouraged the brand for
its initiative. At the same time, positive comments
appear to have made frequent accusatory referenc-
es to opposing individuals by associating them with
prejudice (i.e., homophobia and conservatism). tively associated with the number of responses (Rho
= 0.599, p < 0.001). Thus, social media comments
with more likes were more likely to elicit more re-
sponses, and vice versa. Furthermore, the comments’
sentiment scores were significantly and positively as-
sociated with the number of likes (Rho = 0.312, p <
0.001). In other words, higher sentiment scores (i.e.,
more positive comments) were more likely to attract
more likes from other users. Lastly, a sentiment score
and a number of responses were not associated (Rho
= 0.065, p = 0.145), indicating that neither type of
sentiment (i.e., positive or negative) expressed in the
comments was related to a substantially different (i.e.,
greater or smaller) number of responses. tively associated with the number of responses (Rho
= 0.599, p < 0.001). Thus, social media comments
with more likes were more likely to elicit more re-
sponses, and vice versa. Furthermore, the comments’
sentiment scores were significantly and positively as-
sociated with the number of likes (Rho = 0.312, p <
0.001). In other words, higher sentiment scores (i.e.,
more positive comments) were more likely to attract
more likes from other users. Lastly, a sentiment score
and a number of responses were not associated (Rho
= 0.065, p = 0.145), indicating that neither type of
sentiment (i.e., positive or negative) expressed in the
comments was related to a substantially different (i.e.,
greater or smaller) number of responses. The effects of national context on the metric varia-
bles of the study were examined using a series of in-
dependent sample t-tests (Table 3). The results indi-
cated that the mean number of likes (18.61 vs. 9.98)
and sentiment score (0.62 vs. 0.25) per social media
user comment was statistically significantly greater
for Greece than the USA. 3. RESULTS Activism campaign and type
of sentiment Country
Sentiment
Total
Negative Positive
Greece
Count
231
158
389
% within Country
59.4%
40.6%
100.0%
% within Sentiment
26.5%
87.8%
37.0%
The USA
Count
640
22
662
% within Country
96.7%
3.3%
100.0%
% within Sentiment
73.5%
12.2%
63.0%
Total
Sample
Count
871
180
1051
% within Country
82.9%
17.1%
100.0%
% within Sentiment
100.0%
100.0%
100.0%
% of Total
82.9%
17.1%
100.0%
Note: χ2 = 240.099, p < 0.001; Cramer’s V = 0.478, p < 0.001;
0 cells (0%) have an expected count of less than 5; The
minimum expected count is 66.62. 2. The two posts selected for comment extraction
were publicly available to internet users. Thus,
given that accessing the posts did not require
prior registration to the social network and were
not private, it was assumed that social media
users were cognizant that their comments were
accessible to the broader Internet community. Note: χ2 = 240.099, p < 0.001; Cramer’s V = 0.478, p < 0.001;
0 cells (0%) have an expected count of less than 5; The
minimum expected count is 66.62. Note: χ2 = 240.099, p < 0.001; Cramer’s V = 0.478, p < 0.001;
0 cells (0%) have an expected count of less than 5; The
minimum expected count is 66.62. Lastly, the brand and social network were not iden-
tified throughout this study to minimize the risk
of reverse identification (or reidentification) of in-
dividual users based on the text of their comments. The bivariate relationships among the metric vari-
ables (Table 2) suggested that in both national con-
texts, the number of likes was significantly and posi- 254 http://dx.doi.org/10.21511/im.19(2).2023.20 http://dx.doi.org/10.21511/im.19(2).2023.20 Innovative Marketing, Volume 19, Issue 2, 2023 Table 2. Bivariate correlations (Spearman’s Rho) Table 2. Bivariate correlations (Spearman s Rho)
Variables
Number of likes
Number of responses
Sentiment score
Number of likes
Rho
1.000
p-value
n/a
Number of responses
Rho
0.599*
1.000
p-value
0.000*
n/a
Sentiment score
Rho
0.312*
0.065
1.000
p-value
0.000*
0.145
n/a
Note: * Statistically significant correlations. Note: * Statistically significant correlations. For the brand activism campaign launched in Greece
(Figure 1), the most frequently occurring words in
the negative subsample were “children, shame, dis-
grace, never, again, buy, and products.” The negative
comments of the Greek subsample accused the brand
of subjecting the children to content the respective
online users deemed shameful. http://dx.doi.org/10.21511/im.19(2).2023.20 3. RESULTS For the brand activism campaign launched in the
USA (Figure 2), the most frequently occurring words
in the negative subsample were “child, abuse, never,
products, again, buy, and disgusting.” Thus, the neg-
ative comments of the American subsample accused
the brand of depicting a situation that was abusive
to children. Like the Greek subsample, the negative-
ly predisposed American social media users threat-
ened to abstain from buying the brand’s products to
express their disagreement with the message being
communicated. Regarding the positive comments,
the words most frequently mentioned were “beauti- This study generated simple word clouds to identify
the most prevalent negative and positive sentiments
in the social media user comments. The word clouds
were prepared for each brand activism campaign
separately (i.e., two for Greece and two for the USA)
based on the frequency of words in the positive and
negative subsamples of comments. The larger the
word in each word cloud, the more frequently it ap-
peared in the obtained textual data. Table 3. Independent samples t-tests
Variables
Country
N
Mean
t-test
Std. Dev. Std. Error Mean
Number of likes
Greece
389
18.61
t = 3.81
37.213
1.887
USA
662
9.98
p < 0.001
32.130
1.249
Number of responses
Greece
389
2.39
t = 1.28
5.313
0.269
USA
662
1.71
p = 0.200
9.615
0.374
Sentiment score
Greece
205
0.62
t = 15.19
0.31
2.16%
USA
304
0.25
p < 0.001
0.20
1.15% Table 3. Independent samples t-tests 255 Innovative Marketing, Volume 19, Issue 2, 2023 Figure 1. Negative and positive word cloud for the campaign launched in Greece Figure 1. Negative and positive word cloud for the campaign launched in Greece likes. This finding may be partly explained by the
fact that positive comments have been found to en-
hance the value of brand posts and create empathy
among brand fans (De Vries et al., 2012). ful, thank, love, people, message, see, and representa-
tion.” Hence, positively predisposed American users
praised the brand’s message and efforts to increase
the visibility of gender minorities. Furthermore, pos-
itive comments appeared to emphasize positive emo-
tions and inclusivity. The second similarity observed in consumer re-
sponses to activist advertising across both coun-
tries was that most social media user comments
expressed negative sentiment. 3. RESULTS Consumers in both
countries may likely have opposed the social cause
or idea associated with the brand and, therefore, the
standardized advertising strategy being employed
(Livas, 2021). The initial word frequency analysis in-
dicates that negative comments in Greece and the
USA centered their concerns around children. Thus,
they perceived the main message similarly, irrespec-
tive of execution differences. Following this approach,
the brand’s advertising strategy appears ineffective,
as it contradicts the preferences and opinions held by 4. DISCUSSION Similarities and differences characterize consumer
sentiment toward activist advertising messages in
Greece and the USA. Because of the divisive nature
of sociopolitical issues, social media users were more
likely to reward positive than negative comments. They found the former to be more engaging than
the latter. In other words, comments supporting the
activist advertising message and, consequently, the
company’s stance on the social issue attracted more 256 http://dx.doi.org/10.21511/im.19(2).2023.20 Innovative Marketing, Volume 19, Issue 2, 2023 avoid misunderstanding their message and trigger-
ing negative consumer responses. To achieve this,
multinational companies should identify reliable lo-
cal partners, such as local advertising and market-
ing research agencies, which can enrich the design
and implementation of activist advertising cam-
paigns with local consumer insights. Furthermore,
because consumer attitudes toward social issues may
vary between diverse national contexts and consist-
ently associating the brand with a social cause is a
strategic aspect of marketing communications, a
market-driving philosophy may pose considerable
risks in international settings. A company’s stance
toward a social issue is not just a matter of strategic
positioning, with which consumers may or may not
relate. Since social values indicate the worldviews of
individuals, companies, and institutions, consumers
who oppose the company’s point of view may react
negatively in ways that go beyond changing their
product preferences (e.g., negative word of mouth,
public protests, reporting companies to consum-
er associations and even taking legal action against
business organizations). its international audience. Although marketers have
been advised to drive individuals to adopt sustaina-
ble consumption practices (Sheth & Parvatiyar, 2021)
and/or espouse their social causes (Moorman, 2020),
activist brands are in danger of facing substantial
consumer resistance and denial. Such resistance and
denial may severely impact brands’ performance and,
subsequently, their ability to advance the practices or
causes with which they have aligned (Livas, 2021). Although most comments in both countries were
negative, the relative share of negative comments
was significantly higher in the USA than in Greece. The sheer volume of adverse reactions from the
American audience may also explain the lower aver-
age sentiment score and likes per social media user
comment. Considering that the activist advertising
strategy of the multinational brand examined in this
study was standardized while the executions were lo-
calized, this finding is subject to multiple interpreta-
tions. 4. DISCUSSION From one point of view, the message execution
used in the American version of the campaign may
have incorporated inappropriate communication
tactics for local consumers (Kanso & Nelson, 2002). Alternatively, given the cultural differences between
the two countries (Tamis-LeMonda et al., 2002),
American consumers may have been more negative-
ly predisposed to the social cause incorporated in the
activist advertising message. In this case, contrary to
common international marketing practices (Taylor
& Johnson, 2002), the brand’s advertising strategy
should have been localized to produce more favora-
ble consumer responses (Kanso & Nelson, 2002). Although this study presents new insights into con-
sumer response to international activist advertising,
it has several limitations that offer fruitful avenues
for further research. Because brand activism encom-
passes – but is not limited to – advertising, future
studies could examine consumer sentiment toward
other forms of brand activism (e.g., introduction
of targeted organizational policies, partnerships,
sponsorships, and product modifications). Future
research should include multiple national contexts,
diverse brands, and other business sectors to better
understand international consumers and the impact
of brand activism. When multinational companies consistently asso-
ciate their brands with a social cause, they should
carefully design their advertising execution(s) to http://dx.doi.org/10.21511/im.19(2).2023.20 CONCLUSION This study aimed to compare consumer reactions toward a multinational brand’s advertising strategy
in the USA and Greece. The results show that advertising adaptation to international markets may ex-
tend to both strategic and tactical elements of advertising messages. The investigation of consumers’
sentiment toward international activist advertising in the USA and Greece indicated that social media
users developed similar perceptions and were generally negatively predisposed toward the communicated
advertising messages. Only 3.3% of the comments were positive in the USA and 40.6% in Greece. Even
though the relative share of negative comments was significantly higher in the USA than in Greece, the
similarity of consumers’ perceptions in both countries was evinced by the emphasis on social media user
comments on the same topics. Results of a series of independent sample t-tests indicated that the mean
number of likes (18.61 vs. 9.98) and sentiment score (0.62 vs. 0.25) per social media user comment was 257 Innovative Marketing, Volume 19, Issue 2, 2023 statistically significantly greater for Greece than the USA. Thus, given the study’s results and considering
the characteristics of the international activist advertising campaign being examined (i.e., standardized
advertising strategy with adapted creative execution), multinational companies are advised to focus on
the contextual conditions of the national markets they serve and decide about message appropriateness,
timing, and degree of advertising message adaptation required. The task of multinational brands is much
more complex than that of their local competitors, as they are not only required to examine the adaptation
of their message strategy and execution to the unique market conditions of a single country but also to
continuously monitor the changing consumer values in multiple regions of the world. AUTHOR CONTRIBUTIONS Conceptualization: Christos Livas. Conceptualization: Christos Livas. Data curation: Christos Livas. Formal analysis: Christos Livas, Faidon Theofanidis. Formal analysis: Christos Livas, Faidon Theofanidis.h Investigation: Christos Livas, Faidon Theofanidis, Nansy Karali. Methodology: Christos Livas, Faidon Theofanidis, Nansy Karali. Methodology: Christos Livas, Faidon Theofanidis, Nansy Karali. Project administration: Christos Livas. Resources: Christos Livas. Software: Christos Livas. Supervision: Christos Livas. Validation: Faidon Theofanidis, Nansy Karali. Visualization: Christos Livas. Visualization: Christos Livas. Writing – original draft: Christos Livas. Writing – original draft: Christos Livas. Writing – review & editing: Faidon Theofanidis, Nansy Karali. Writing – review & editing: Faidon Theofanidis, Nansy Karali. 3.
De Mooij, M. (2003). Conver-
gence and divergence in consumer
behaviour: Implications for global
advertising. International Journal
of Advertising, 22(2), 183-202.
https://doi.org/10.1080/02650487.
2003.11072848 4.
De Vries, L., Gensler, S., & Lee-
flang, P. S. (2012). Popularity of
brand posts on brand fan pages:
An investigation of the effects of
social media marketing. Journal
of Interactive Marketing, 26(2),
83-91. https://doi.org/10.1016/j.
intmar.2012.01.003 7.
Elinder, E. (1965). How inter-
national can European adver-
tising be? Journal of Market-
ing, 29(2), 7-11. https://doi.
org/10.1177/002224296502900203 9.
Harris, G. (1994). International
advertising standardization:
What do the multinationals
actually standardize? Journal
of International Marketing,
2(4), 13-30. https://doi.or-
g/10.1177/1069031X9400200402 REFERENCES 9. Harris, G. (1994). International
advertising standardization:
What do the multinationals
actually standardize? Journal
of International Marketing,
2(4), 13-30. https://doi.or-
g/10.1177/1069031X9400200402 1. Aaker, D. A., & Myers, J. G. (1975). Advertising management. New
Jersey: Prentice-Hall. 2. Caillat, Z., & Mueller, B. (1996). The influence of culture on
American and British advertis-
ing: An exploratory comparison
of beer advertising. Journal of
5. Douglas, S. P., & Wind, Y. (1987). The myth of globaliza-
tion. Columbia Journal of World
Business, 22(4), 19-29. Retrieved
from https://faculty.wharton. upenn.edu/wp-content/up-
loads/2012/04/8712_The_Myth_
of_Globalization.pdf 1. Aaker, D. A., & Myers, J. G. (1975). Advertising management. New
Jersey: Prentice-Hall. 1. Aaker, D. A., & Myers, J. G. (1975). Advertising management. New
Jersey: Prentice-Hall. 2. Caillat, Z., & Mueller, B. (1996). The influence of culture on
American and British advertis-
ing: An exploratory comparison
of beer advertising. Journal of
Advertising Research, 36(3), 79-89. Retrieved from https://link.gale. com/apps/doc/A18764041/AON
E?u=googlescholar&sid=bookma
rk-AONE&xid=57f76609
3. De Mooij, M. (2003). Conver-
gence and divergence in consumer
behaviour: Implications for global
advertising. International Journal
of Advertising, 22(2), 183-202. https://doi.org/10.1080/02650487. 2003.11072848
4. De Vries, L., Gensler, S., & Lee-
flang, P. S. (2012). Popularity of
brand posts on brand fan pages:
An investigation of the effects of
social media marketing. Journal
of Interactive Marketing, 26(2),
83-91. https://doi.org/10.1016/j. intmar.2012.01.003
5. Douglas, S. P., & Wind, Y. (1987). The myth of globaliza-
tion. Columbia Journal of World
Business, 22(4), 19-29. Retrieved
from https://faculty.wharton. upenn.edu/wp-content/up-
loads/2012/04/8712_The_Myth_
of_Globalization.pdf
6. Duncan, T., & Ramaprasad, J. (1995). Standardized multina-
tional advertising: The influencing
factors. Journal of Advertising,
24(3), 55-68. https://doi.org/10.10
80/00913367.1995.10673483
7. Elinder, E. (1965). How inter-
national can European adver-
tising be? Journal of Market-
ing, 29(2), 7-11. https://doi. org/10.1177/002224296502900203
8. Finne, Å., & Grönroos, C. (2009). Rethinking marketing com-
munication: From integrated
marketing communication to
relationship communication. Journal of Marketing Communica-
tions, 15(2-3), 179-195. https://doi. org/10.1080/13527260902757654
9. Harris, G. (1994). International
advertising standardization:
What do the multinationals
actually standardize? Journal
of International Marketing,
2(4), 13-30. https://doi.or-
g/10.1177/1069031X9400200402
10. Hatzithomas, L., Fotiadis, T. A.,
& Coudounaris, D. N. (2016). Standardization, adaptation, and
personalization of international
corporate social media communi-
cations. Psychology & Marketing,
33(12), 1098-1105. https://doi. org/10.1002/mar.20944
11. Holbrook, M. B. (1987). Mir-
ror, mirror, on the wall, what’s
unfair in the reflections on
advertising? Journal of Market-
ing, 51(3), 95-103. https://doi. org/10.1177/002224298705100307
12. James, W. L., & Hill, J. S. (1991). International advertising messages:
To adapt or not to adapt. REFERENCES Journal of
Advertising Research, 31(3), 65-71. Retrieved from https://psycnet.apa. org/record/1991-34895-001 2. Caillat, Z., & Mueller, B. (1996). The influence of culture on
American and British advertis-
ing: An exploratory comparison
of beer advertising. Journal of
Advertising Research, 36(3), 79-89. Retrieved from https://link.gale. com/apps/doc/A18764041/AON
E?u=googlescholar&sid=bookma
rk-AONE&xid=57f76609 10. Hatzithomas, L., Fotiadis, T. A.,
& Coudounaris, D. N. (2016). Standardization, adaptation, and
personalization of international
corporate social media communi-
cations. Psychology & Marketing,
33(12), 1098-1105. https://doi. org/10.1002/mar.20944 6. Duncan, T., & Ramaprasad, J. (1995). Standardized multina-
tional advertising: The influencing
factors. Journal of Advertising,
24(3), 55-68. https://doi.org/10.10
80/00913367.1995.10673483 3. De Mooij, M. (2003). Conver-
gence and divergence in consumer
behaviour: Implications for global
advertising. International Journal
of Advertising, 22(2), 183-202. https://doi.org/10.1080/02650487. 2003.11072848 7. Elinder, E. (1965). How inter-
national can European adver-
tising be? Journal of Market-
ing, 29(2), 7-11. https://doi. org/10.1177/002224296502900203 11. Holbrook, M. B. (1987). Mir-
ror, mirror, on the wall, what’s
unfair in the reflections on
advertising? Journal of Market-
ing, 51(3), 95-103. https://doi. org/10.1177/002224298705100307 8. Finne, Å., & Grönroos, C. (2009). Rethinking marketing com-
munication: From integrated
marketing communication to
relationship communication. Journal of Marketing Communica-
tions, 15(2-3), 179-195. https://doi. org/10.1080/13527260902757654 8. 4. De Vries, L., Gensler, S., & Lee-
flang, P. S. (2012). Popularity of
brand posts on brand fan pages:
An investigation of the effects of
social media marketing. Journal
of Interactive Marketing, 26(2),
83-91. https://doi.org/10.1016/j. intmar.2012.01.003 12. James, W. L., & Hill, J. S. (1991). International advertising messages:
To adapt or not to adapt. Journal of
Advertising Research, 31(3), 65-71. Retrieved from https://psycnet.apa. org/record/1991-34895-001 258 http://dx.doi.org/10.21511/im.19(2).2023.20 Innovative Marketing, Volume 19, Issue 2, 2023 13. Kale, S. H. (1991). Culture‐spe-
cific marketing communica-
tions: an analytical approach. International Marketing Re-
view, 8(2), 18-30. https://doi. org/10.1108/02651339110004078 31. Pollay, R. W., & Gallagher, K. (1990). Advertising and cultural
values: Reflections in the distorted
mirror. International Journal of
Advertising, 9(4), 359-372. https://
doi.org/10.1080/02650487.1990.1
1107165 23. Okazaki, S., Taylor, C. R., & Doh, J. P. (2007). Market convergence and
advertising standardization in the
European Union. Journal of World
Business, 42(4), 384-400. https://
doi.org/10.1016/j.jwb.2007.06.002 24. Onkvisit, S., & Shaw, J. J. (1999). Standardized international
advertising: Some research is-
sues and implications. Journal of
Advertising Research, 39(6), 19-24. Retrieved from https://go.gale. com/ps/i.do?p=AONE&u=googl
escholar&id=GALE|A60905112&
v=2.1&it=r&sid=AONE&asid=3
a056ddc 14. Kanso, A., & Nelson, R. A. (2002). Advertising localization overshad-
ows standardization. Journal of
Advertising Research, 42(1), 79-89. https://doi.org/10.2501/JAR-42-
1-79-89 32. REFERENCES Rajabi, M., Dens, N., De Pels-
macker, P., & Goos, P. (2017). Consumer responses to different
degrees of advertising adaptation:
The moderating role of national
openness to foreign markets. In-
ternational Journal of Advertising,
36(2), 293-313. https://doi.org/10. 1080/02650487.2015.1110949 15. Kennedy, A. M., & Parsons, A. (2012). Macro‐social market-
ing and social engineering: A
systems approach. Journal of Social
Marketing, 2(1), 37-51. https://doi. org/10.1108/20426761211203247 25. Pagani, M., Goldsmith, R., &
Perracchio, A. (2015). Standard-
ization vs. adaptation: Consumer
reaction to TV ads containing
subtitled or English dubbed ads. International Journal of Advertis-
ing, 34(4), 702-714. https://doi.org
/10.1080/02650487.2015.1009349 33. Rodman, H. (1967). Marital power
in France, Greece, Yugoslavia, and
the United States: A cross-national
discussion. Journal of Marriage
and the Family, 29(2), 320-324. https://doi.org/10.2307/349693 16. Levitt, T. (1983). The globaliza-
tion of markets. Harvard Business
Review, 61(3), 92-102. Retrieved
from https://hbr.org/1983/05/the-
globalization-of-markets 34. Schmid, S., & Kotulla, T. (2011). 50 years of research on inter-
national standardization and
adaptation – From a systematic
literature analysis to a theoretical
framework. International Business
Review, 20(5), 491-507. https://doi. org/10.1016/j.ibusrev.2010.09.003 17. Livas, C. (2021). The powers
and perils of societal advertis-
ing. Journal of Macromarket-
ing, 41(3), 454-470. https://doi. org/10.1177/0276146720978261 26. Papavassiliou, N., & Statha-
kopoulos, V. (1997). Stan-
dardization versus adaptation
of international advertising
strategies: Towards a framework. European Journal of Market-
ing, 31(7), 504-527. https://doi. org/10.1108/03090569710176646 18. Miracle, G. E., Yeol Chang, K., &
Taylor, C. R. (1992). Culture and
advertising executions: A com-
parison of selected characteristics
of Korean and US television com-
mercials. International Marketing
Review, 9(4), 5-17. https://doi. org/10.1108/02651339210017082 35. Sheth, J. N., & Parvatiyar, A. (2021). Sustainable marketing:
Market-driving, not market-
driven. Journal of Macromarket-
ing, 41(1), 150-165. https://doi. org/10.1177/0276146720961836 27. Penz, E., & Stöttinger, B. (2015). Consuming ‘European’: Capturing
homogeneity and heterogeneity in
consumer culture of five European
countries. European Journal of
International Management, 9(3),
326-341. https://doi.org/10.1504/
EJIM.2015.069162 36. Sriram, V., & Gopalakrishna, P. (1991). Can advertising be stan-
dardized among similar countries? A cluster-based analysis. Interna-
tional Journal of Advertising, 10(2),
137-149. https://doi.org/10.1080/0
2650487.1991.11104444 19. Moorman, C. (2020). Com-
mentary: Brand activism
in a political world. Journal
of Public Policy & Market-
ing, 39(4), 388-392. https://doi. org/10.1177/0743915620945260 28. Petit, T. A., & Zakon, A. (1962). Advertising and social
values. Journal of Market-
ing, 26(4), 15-17. https://doi. org/10.1177/002224296202600404 20. Moriarty, S. E., & Duncan, T. R. (1991). Global advertising: Issues
and practices. 40. Vrontis, D., & Thrassou, A. (2007).
Adaptation vs. standardization
in international marketing – The
country-of-origin effect. In-
novative Marketing, 3(4), 7-20.
Retrieved from https://pure.unic.
ac.cy/en/publications/adaptation- 41. Zandpour, F., & Harich, K. R.
(1996). Think and feel country
clusters: A new approach to
international advertising stan-
dardization. International Journal
of Advertising, 15(4), 325-344.
https://doi.org/10.1080/02650487.
1996.11104663 39. Theodosiou, M., & Leonidou,
L. C. (2003). Standardization
versus adaptation of interna-
tional marketing strategy: An
integrative assessment of the
empirical research. International REFERENCES Current Issues and
Research in Advertising, 13(1-2),
313-341. https://doi.org/10.1080/0
1633392.1991.10504970 37. Tamis-LeMonda, C. S., Wang,
S., Koutsouvanou, E., & Al-
bright, M. (2002). Childrearing
values in Greece, Taiwan, and
the United States. Parenting:
Science and Practice, 2(3), 185-
208. https://doi.org/10.1207/
S15327922PAR0203_01 29. Pollay, R. W. (1983). Measuring
the cultural values manifest in
advertising. Current Issues and
Research in Advertising, 6(1), 71-
92. Retrieved from https://www. tandfonline.com/doi/abs/10.1080/
01633392.1983.10505333 21. Mueller, B. (1986). Reflections of
culture: An analysis of Japanese
and American advertising appeals. Journal of Advertising Research, 27,
51-59. Retrieved from https://eric. ed.gov/?id=ED271776 38. Taylor, C. R., & Johnson, C. (2002). Standardized vs. specialized inter-
national advertising campaigns:
What we have learned from aca-
demic research in the 1990s. In C. R. Taylor (Ed.), Advances in Inter- 30. Pollay, R. W. (1986). The dis-
torted mirror: Reflections on
the unintended consequences
of advertising. Journal of Mar-
keting, 50(2), 18-36. https://doi. org/10.1177/002224298605000202 22. Ogilvy, D. (1985). Ogilvy on adver-
tising. New York: Vintage Books. 259 http://dx.doi.org/10.21511/im.19(2).2023.20 Innovative Marketing, Volume 19, Issue 2, 2023 national Marketing, 12 (pp. 45-66). Emerald Group Publishing Lim-
ited. http://dx.doi.org/10.1016/
S1474-7979(02)12019-9
39. Theodosiou, M., & Leonidou,
L. C. (2003). Standardization
versus adaptation of interna-
tional marketing strategy: An
integrative assessment of the
empirical research. International
Business Review, 12(2), 141-171. https://doi.org/10.1016/S0969-
5931(02)00094-X
40. Vrontis, D., & Thrassou, A. (2007). Adaptation vs. standardization
in international marketing – The
country-of-origin effect. In-
novative Marketing, 3(4), 7-20. Retrieved from https://pure.unic. ac.cy/en/publications/adaptation-
vs-standardization-in-internation-
al-marketing-the-coun
41. Zandpour, F., & Harich, K. R. (1996). Think and feel country
clusters: A new approach to
international advertising stan-
dardization. International Journal
of Advertising, 15(4), 325-344. https://doi.org/10.1080/02650487. 1996.11104663 national Marketing, 12 (pp. 45-66). Emerald Group Publishing Lim-
ited. http://dx.doi.org/10.1016/
S1474-7979(02)12019-9 vs-standardization-in-internation-
al-marketing-the-coun Business Review, 12(2), 141-171. https://doi.org/10.1016/S0969-
5931(02)00094-X vs-standardization-in-internation-
al-marketing-the-coun 41. Zandpour, F., & Harich, K. R. (1996). Think and feel country
clusters: A new approach to
international advertising stan-
dardization. International Journal
of Advertising, 15(4), 325-344. https://doi.org/10.1080/02650487. 1996.11104663 40. Vrontis, D., & Thrassou, A. (2007). Adaptation vs. standardization
in international marketing – The
country-of-origin effect. In-
novative Marketing, 3(4), 7-20. Retrieved from https://pure.unic. ac.cy/en/publications/adaptation- 39. Theodosiou, M., & Leonidou,
L. C. (2003). Standardization
versus adaptation of interna-
tional marketing strategy: An
integrative assessment of the
empirical research. International 260 http://dx.doi.org/10.21511/im.19(2).2023.20 http://dx.doi.org/10.21511/im.19(2).2023.20
|
https://openalex.org/W4311012657
|
https://zenodo.org/records/7421381/files/JARTES2021011213.pdf
|
Latin
| null |
STUDY OF THE INTERACTION OF COSTS AND BENEFITS OF THE ENTERPRISE (FIRM)
|
Zenodo (CERN European Organization for Nuclear Research)
| 2,022
|
cc-by
| 2,946
|
Journal of Academic Research
and Trends in Educational
Sciences
Journal home page:
http://ijournal.uz/index.php/jartes STUDY OF THE INTERACTION OF COSTS AND BENEFITS OF THE
ENTERPRISE (FIRM) 1 Assitant, Jizzakh branch of the National University of Uzbekistan, UZB (baxrom3500@gmail.com) 2 Student, Jizzakh branch of the National University of Uzbekistan, UZB (dinorasaydullayeva6@gma 2181-2675/© 2022 in XALQARO TADQIQOT LLC.
DOI: 10.5281/zenodo.7421381
This is an open access article under the Attribution 4.0 International (CC
BY 4.0) license (https://creativecommons.org/licenses/by/4.0/deed.ru) STUDY OF THE INTERACTION OF COSTS AND BENEFITS OF THE
ENTERPRISE (FIRM) Xaydarov Baxrom Xolmuradovich1
Saydullayeva Dinora2 Jizzakh branch of the National University of Uzbekistan Journal of Academic Research and Trends in Educational Sciences (JARTES)
VOLUME 1, ISSUE 12 / ISSN 2181-2675 ABSTRACT Any company allocates certain funds for the purchase of factors
of production that can be used. These monetary costs were called
production costs. The most economically useful and efficient
production model is the model that keeps production costs as
low as possible. market, expenditure, economic
resource, production costs,
classical, neoclassical, modern
concept, social costs, fixed
capital, cost, direct production,
transaction costs, additional
transaction, net transaction,
marginalist standard profit ,
internal cost, external cost,
straight cost, curve cost,
economic or net profit, profit
rate 2181-2675/© 2022 in XALQARO TADQIQOT LLC. DOI: 10.5281/zenodo.7421381
This is an open access article under the Attribution 4.0 International (CC
BY 4.0) license (https://creativecommons.org/licenses/by/4.0/deed.ru) DOI: 10.5281/zenodo.7421381
This is an open access article under the Attribution 4.0 International (CC
BY 4.0) license (https://creativecommons.org/licenses/by/4.0/deed.ru) KALIT SO‘ZLAR: Har qanday kompaniya foydalanishi mumkin bo’lgan ishlab
chiqarish omillarini sotib olish uchun ma’lum mablag’larni
ajratadi. Ushbu pul xarajatlari ishlab chiqarish xarajatlari deb
ataldi. Iqtisodiy jihatdan eng foydali va samarali ishlab chiqarish
modeli ishlab chiqarish xarajatlarini imkon qadar past darajada
ushlab turaydigan modeldir. bozor, sarfxarajat, iqtisodiy
resurs, ishlab chiqarish
xarajatlari, klassik,
neoklassik, zamonaviy
kontsepsiya, ijtimoiy
xarajatlar, asosiy kapital,
tannarx, bevosita ishlab
chiqarish, muomala
xarajatlari, qo’shimcha
muomala, sof muomala,
mirjinalistlar me’yordagi
foyda, ichki xarajat, tashqi
xarajat, to’g’ri xarajat, egri
xarajat, iqtisodiy yoki sof
foyda, foyda normasi Korxonalarning bozorga mahsulot yetkazib berishga bo’lgan layoqatini aniqlab
beruvchi muhim omil sarf-xarajatlar darajasi hisoblanadi. Har qandey tovarni ishlab
chiqarish iqtisodiy resurs sarflarini taqozo qilib, ular ham ma’lum narxga ega bo’ladi. Korxona bozorga taklif qilgan tovar miqdori iqtisodiy xarajatlar(resurs narxlari) darajasiga,
resurslardan foydalanish samaradorligi va tovarlar bozorida sotilgan narxlarga bog’liq. Bu
bobda sarf-xarajatlarning umumiy tabiati va tarkibiga to’xtalib, foydaning tashkil topishi
jarayoni tahlil qilinadi. Shu bilan bir qatorda, kishilarning hayot kechirishi va turmush
darajasini aniqlab beruvchi daromadlarning asosiy turi bo’lgan ish haqini tahlil qilish
muhim ahamiyat kasb etadi. Bobda ish haqining iqtisodiy tabiati bilan bog’liq muammolar
va uning shakllari hamda bozor munosabatlari sharoitida ish haqi darajasiga ta’sir
ko’rsatuvchi omillar ko’rib chiqiladi. Milliy iqtisodiyotdagi ishlab chiqarish birliklari (korxona, firma)o’z faoliyati
natijalaridan ko’proq foyda olishga harakat qiladilar. Har qandey korxona oladigan foyda
nafaqat o’zining tovarini ancha yuqori narxlarda sotishga, balki tovar ishlab chiqarish va
uni sotishga qilinadigan harajatlarni kamaytirishga ham intiladi. Tovarni sotish narxlari
asosan, korxona faoliyatiga bog’liq bo’lmagan tashqi sharoitlar bilan belgilansa, ishlab
chiqarish xarajatlari korxonaning ishlab chiqarish va tayyor tovarlarni sotish jarayonlarini
tashkil qilish samaradorligi darajasiga bog’liq. Lekin har qandey tovarni ishlab chiqarish va
sotish uchun ma’lum sarf-xarajatlar talab etiladi. Hozirda shlab chiqarish xarajatlarini
tadqiq etish ikki xil yondashuv-klassik va neoklassik yoki zamonaviy konseptsiyalardan
foydalaniladi. Klassik nazariya yondashuviga ko’ra, ishlab chiqarish xarajatlari-bu mahsulot
ishlab chiqarish uchun amalga oshirilgan barcha jonli mehnat, pul va moddiy sarflardir. Umumiy nazariya jihatdan quyidagilarni farqlash lozim: 1)
Ishlab chiqarishning ijtimoiy xarajatlari yoki mahsulot qiymati; 1)
Ishlab chiqarishning ijtimoiy xarajatlari yoki mahsulot qiymati; 72 Journal of Academic Research and Trends in Educational Sciences (JARTES)
VOLUME 1, ISSUE 12 / ISSN 2181-2675 tomonidan zarur resurs va xizmatlarni tashqaridan to’lov asosida jalb etishi uchun sarf
qilingan xarajatlardir.Bundey xarajatlarga yollanma ishchilar ish haqi, xomashyo va
materiallar uchun to’lovlar, kredit uchun foiz to’lovlari ijaraga olingan yer uchun renta,
transport xizmati va boshqa har xil xizmatlar uchun to’lovlar kiradi. Tashqi xarajatlar to’lov
hujjatlari bilan rasmiylashtiriladi, shu sababli buxgalteriya xarajatlari deb ham ataladi. Korxonaning o’ziga tegishli bo’lagan resurslardan foydalanishi bilan bog’liq xarajatlar ichki
xarajatlar deyiladi. Bundey xarajatlar pul to’lovlari shaklida chiqmaydi. Shu sababli ichki
xarajatlar darajasini baholash o’z resurslari qiymatini shunga o’xshash resurlarning
bozordagi narxlariga taqqoshlash orqali amalga oshiriladi. Tashqi va ichki xarajatlarning mohiyatini ochib berish, ularning bir-biridan farqini
tushuntirishda bugungi kunda xo’jalik amaliyotimizda faoliyot yuritayotgan ko’plab yakka
tartibdagi tadbirkorlikni yaqqol misol tariqasida keltirish mumkin. Aytaylik, biron-bir
tadbirkor o’zigan qarashli bo’lgan xonadondan kichik ishlab chiqarish sexi tashkil qildi.Bu
yerda uning tashqi xarajatlari anniq: ishlab chiqarish uchun zarur bo’lgan xomashyo uchun
to’lov, elektr energiyasi, suv va boshqa kommunal xizmatlar uchun to’lovlar, transport
xizmatlari uchun to’lov va boshqalar. Bu o’rinda ichki xarajatla nimadan iborat bo’ladi,
degan savol tug’ilishi mumkin. Misolimizdan ko’rindiki, tadbirkorlik sex binosi sifatida o’z
xonadonidan foydalanyapti. Shubhasiz, u o’z xonadonidan foydalanganlgi uchun o’ziga haq
to’lamaydi, biroq agar u ushbu xonadonni biron-bir kishiga ijaraga berganida ma’lum
miqdorda (aytaylikbir oyga 200ming so’m) pul daromadi olgan bo’lar edi. Uning
xonadonidan sex sifatida foydalanish muqobil holatda kelishi mumkin bo’lgan ijara
to’lovidan, ya’ni 200mimg so’mdan mahrum etmoqda. Demak, bu o’rinda
tadbirkor’’ko’ziga ko’rinmagan” holda 200 ming so’m sarflamoqda, ya’ni ichki xarajat
qilinmoqda. Bu turdagi ichki xarajatlarga yana tadbirkorning o’zi ish haqini, agar oila
a’zolari mehnatidan foydalansa, ularning ish haqini va shung o’xshash boshqa xarajatlarni
kiritish mmkin. Shu bilan birga tadbirkorlik faoliyatini ushlab turish zarur bo’lgan to’lov-
me’yordagi foyda ham renta va ish haqi bilan birga xartajatlarning tarkibiy qismi
hisoblanadi. Me’yordagi foyda iqtisodiy foydadan farq qiladi. Me’yordagi foyda-buiqtisodiy
resurs sifatidagi tadbirkorlik qobilyatini rag’batlantirib turish uchun to’lanadigan haq
hisoblanadi. Agar biron-bir faoliyat turi me’yordagi foyda keltirilmasa, tadbirkor bu faoliyat
turi bilan shug’ullanishni to’xtaydi va o’zining kuch-quvvatini boshqa faoliyatga sarflaydi. Sarf-xarajatlarning ichki va tashqi xarajatlarga ajratish korxona iqtisodiy faoliyati
samaradorligini oshirish yo’llarini qiyosiy tahlil qilish imkonini beradi. Ishlab chiqarish
hajmining o’zgarishiga qisqarishi yoki ortishiga) ta’sir qilmaydiga xarajatlar doimiy
xarajatlar deyiladi. O’zgaruvchi xarajatlar(O’X)deb ishlab chiqarish hajmining o’zgarishiga
ta’sir qiladigan xarajatlarga aytiladi. Ishlab chiqarishning har bir darajasida doimiy va
o’zgaruvchi xarajatlar yig’indisi umumiy xarajatlar(UX) ni tashkil qiladi. Doimiy(DX),
o’zgaruvchi(O’X) va umumiy(UX)xarajat. Journal of Academic Research and Trends in Educational Sciences (JARTES)
VOLUME 1, ISSUE 12 / ISSN 2181-2675 2) Korxona(firma)ning individual ishlab chiqarish xarajatlari. Ijtimoiy ishlab chiqarish xarajatlari-bu mahsulot ishlab chiqarish uchun ijtimoiy
zaruriy mehnatning umumiy(jonli va moddiylashgan) sarflaridir. Ular mazkur mahsulotni
ishlab chiqarish jamiyat uchun qanchaga tushganligini ko’rsatadi. Tovar ishlab chiqarish
sharoitida ijtimoiy xarajatlar pul shaklida namoyon bo’ladi va tovar qiymatiga muvofiq
tushadi, ya’ni: W=c+v+m, yerda: w-ijtimoiy ishlab chiqarish xarajatlari yoki mahsulot qiymati; bu yerda: w-ijtimoiy ishlab chiqarish xarajatlari yoki mahsulot qiymati;
c-iste’mol qilingan ishlab chiqarish vositalari qiymati; v-ishchi kuchi qiymati (ish
haqi); m- qo’shimcha qiymat. c-iste’mol qilingan ishlab chiqarish vositalari qiymati; v-ishchi kuchi qiymati (ish
haqi); m- qo’shimcha qiymat. Korxona ishlab chiqarish xarajatlari deganda tovar va xizmatlarni ishlab chiqarish va
iste’molchilarga yetkazib berishga qilinadigan barcha sarflar tushuniladi: k=c+v. Korxona ishlab chiqarish xarajatlari tarkibiga xomashyo, asosiy va yordamchi
materiallar, yonilg’i va energiya xarajatlari, asosiy kapital amortizatsiyasi, ish haqi va
ijtimoiy sug’urta ajratmalari, foiz to’lovlari va boshqa xarajatlar kiradi. Korxona tomonidan
ishlab chiqarishga qilingan barcha sarf-xarajatlarning puldagi ifodasi mahsulot tannarxini
tashkil qiladi. Bevosita ishlab chiqarish xarajatlari faqat tovar ishlab chiqarish bilan bog’liq
xarajatlarni o’z ichiga olib, tovar birligi qiymating faqat bir qismini tashkil qiladi.Ishlab
chiqarish xarajatlari tovar qiymatidan foyda miqdoriga kam bo’ladi. Muomala xarajatlari tushunchasi tovarlarni sotish jarayoni bilan bog’liq bo’lib, shu
tovarlarni ishlab chiqaruvchidan iste’molchiga yetkazilguncha ketadigan sarflarga aytiladi. Ular ikki guruhga bo’linadi: qo’shimcha muomala xarajatlari va sof muomala xarajatlari. Tovarlarni o’rash, qadoqlash, saralash, transportga ortish, tashish va saqlash xarajatlari
qo’shimcha muomala xarajatlari hisoblanadi. Muomala xarajatlarining bu turlari ishlab
chiqarish xarajatlarining davomi hisoblanib, tovar qiymatiga kiradi va uning qiymatini
oshiradi. Xarajatlar tovarlar sotilgandan keyin olingan pul tushumi summasidan qoplanadi. Sof muomala xarajatlari tovarni sotish bilan bog’liq bo’lib, sotuvchilarning maoshi,
marketing (iste’molchilar talabini o’rganish), reklama va shu kabi xarajatlardan iborat
bo’ladi. Sof muomala xarajatlari tovar qiymatini oshirmaydi va ishlab chiqarish jarayonida
yaratilgan tovarni sotgandan keyin olingan foyda hisobidan qoplanadi. Ishlab chiqarish xarajatlarining ikkinchi yo’nalishdagi konsepsiyalari marjinalistlar
va neoklassik tomonidan ishlab chiqilgan bo’lib, ular bu boradagi klassik nazariyalarni
ham ma’lum darajada hisobga oladilar. Biroq, bu konseptsiyalarning o’ziga xos tomoni
shundaki, ular ishlab chiqarish xarajatlarini tushuntirishda resurslarning cheklanganligi va
ulardan muqobil foydalanish imkoniyatlaridan kelib chiqadilar. Marjinalistik sarf-xarajatlar nazariyasi bo’yicha korxona ishlab chiqarish jarayonida
foydalanilgan resurslar o’z resurlari yoki jalb qilingan resurslar bo’lishi mumkin. Shunga
ko’ra xarajatlar ichki yoki tashqi xarajatlarga bo’linadi. Tashqi xarajatlar korxona 73 Mahsulot birligini ishlab chiqarishga qilinadigan
sarf-xarajatlarni hisoblash uchun o’rtacha umumiy, o’rtacha doimiy va o’rtacha o’zgaruvchi
xarajatlar
tushunchalaridan
foydalaniladi. O’rtacha
umumiy
xarajatlar
yalipi 74 Journal of Academic Research and Trends in Educational Sciences (JARTES)
VOLUME 1, ISSUE 12 / ISSN 2181-2675 Journal of Academic Research and Trends in Educational Sciences (JARTES)
VOLUME 1, ISSUE 12 / ISSN 2181-2675 (umumiy)xarajatlarning ishlab ishlab chiqarilgan mahsulot miqdori nisbatiga teng:
O’UX=UX/M; bu
yerda:O’UX-o’rtacha
umumiy
xarajatlar;UX-umumiy
xarajatlar;M-ishlab
chiqarilgan mahsulot miqdori. Eng yuqori darajada foyda olishga erishish uchun tovar ishlab chiqarishning zarur
miqdorini aniqlash lozim.Bunda iqtisodiy iqtisodiy tahlil vositasi bo’lib so’ngi qo’shilgan
xarajat tushunchasi xizmat qiladi.So’ngi qo’shilgan xarajat deb mahsulotning navbatdagi
birligini ishlab chiqarish bilan bog’liq qo’shimcha xarajatlarga aytiladi: SQX=UX/M Bu yerda: SQX-so’nggi qo’shilgan xarajat; UX-umumiy xarajatlarning o’zgarishi;M-
mahsulot miqdorini o’zgarishi. Xulosa: Ishlab chiqarish xarajatlari — korxonaning mahsulot i. ch. maqsadlarida,
iqtisodiy resurslar sotib olish uchun qilgan pul sarflari. Firma oʻz faoliyatini bozordan
moddiy resurslar, yaʼni asbob-uskuna, dastgohlar, transport va aloqa vositalari, xom ashyo,
yoqilgʻi, har xil materiallarni, mehnat bozoridan ish kuchini sotib olishdan boshlaydi. Shunga muvofiq holda Ishlab chiqarish xarajatlari tarkibiga xom ashyo, asosiy va yordamchi
materiallar, yonilgʻi va energiya xarajatlari, asosiy kapital amortizatsiyasi, ish haqi va
ijtimoiy sugʻurtaga ajratmalar, foiz toʻlovlari va b. xarajatlar kiradi. Ishlab chiqarish
xarajatlariga qilingan barcha xarajatlarning puldagi ifodasi mahsulot tannarxinn tashkil
qiladi. Ishlab chiqarish xarajatlarini oʻrganishga iqtisodchilar turlicha yondoshadilar. Jumladan, xarajatlarning qiymat nazariyasiga koʻra, Ishlab chiqarish xarajatlari quyidagi
turlarga boʻlinadi: doimiy xarajatlar: — korxona toʻlov majburiyatlari, soliqlar,
amortizatsiya ajratmalari, ijara haqi, qoʻriqlash xizmati xarajatlari, boshqaruv xodimlari
maoshi va b; oʻzga-ruvchan xarajatlar: — xom ashyo, materiallar, yonilgʻi, transport xizmati,
ishchilar ish haqi va shu kabilar uchun xarajatlar. Foydalanilgan adabiyotlar: 1. O’lmasov A. Vahobov A. Iqtisodiyot nazariyasi:Darslik.-T:’’SHarq’’ nashriyot-
matbaa aksiyadorlik kompaniyasi Bosh tahririyati, 2006-480b. 2. Shodmonov Sh. Sh.G’afurov U. V. Iqtisodiyot nazariyasi(darslik).-T: Fan va
texnologiya nashriyoti, 2005-784b. 3. Xaydarov B., Saitov S. Raqamli iqtisodiyot tushunchasi va afzalliklari
//Zamonaviy
innovatsion
tadqiqotlarning
dolzarb
muammolari
va
rivojlanish
tendensiyalari: yechimlar va istiqbollar. – 2022. – Т. 1. – №. 1. – С. 634-635. 4. Xaydarov B. X., Saitov S. A. RAQAMLI IQTISODIYOT TUSHUNCHASI,
AFZALLIKLARI AMALIY AHAMIYATI VA XORIJIY TAJRIBA //Academic research in
educational sciences. – 2022. – Т. 3. – №. 5. – С. 151-156. 5. Хайдаров
Б. ИҚТИСОДИЙ
ИСЛОҲОТЛАРНИ
РИВОЖЛАНТИРИШДА
КАМБАҒАЛЛИКНИ ҚИСҚАРТИРИШ //Экономика и образование. – 2021. – №. 4. – С. 288-292. 75 Journal of Academic Research and Trends in Educational Sciences (JARTES)
VOLUME 1, ISSUE 12 / ISSN 2181-2675 6. Бахром Х. Х. БИЗНЕСНИ РЕЖАЛАШТИРИШ ТАРТИБЛАРИ //PEDAGOGS
jurnali. – 2022. – Т. 12. – №. 2. – С. 139-142. 6. Бахром Х. Х. БИЗНЕСНИ РЕЖАЛАШТИРИШ ТАРТИБЛАРИ //PEDAGOGS
jurnali. – 2022. – Т. 12. – №. 2. – С. 139-142. 7. Nodira T., Xaydarov B., Zafar Q. THE ROLE AND SIGNIFICANCE OF
COMPETITION AND MONOPOLY IN THE ECONOMY //Journal of Academic Research and
Trends in Educational Sciences. – 2022. – Т. 1. – №. 11. – С. 241-245. 7. Nodira T., Xaydarov B., Zafar Q. THE ROLE AND SIGNIFICANCE OF
COMPETITION AND MONOPOLY IN THE ECONOMY //Journal of Academic Research and
Trends in Educational Sciences. – 2022. – Т. 1. – №. 11. – С. 241-245. 8. Xaydarov B. IMPACT OF INTELLECTUAL PROPERTY PROTECTION ON THE
DIGITAL ECONOMY //Journal of Academic Research and Trends in Educational Sciences. –
2022. – Т. 1. – №. 11. – С. 163-174. 8. Xaydarov B. IMPACT OF INTELLECTUAL PROPERTY PROTECTION ON THE
DIGITAL ECONOMY //Journal of Academic Research and Trends in Educational Sciences. –
2022. – Т. 1. – №. 11. – С. 163-174. 9. Nodira T., Xaydarov B., Zafar Q. THE ROLE AND SIGNIFICANCE OF
COMPETITION AND MONOPOLY IN THE ECONOMY //Journal of Academic Research and
Trends in Educational Sciences. – 2022. – Т. 1. – №. 11. – С. 241-245. 9. Nodira T., Xaydarov B., Zafar Q. THE ROLE AND SIGNIFICANCE OF
COMPETITION AND MONOPOLY IN THE ECONOMY //Journal of Academic Research and
Trends in Educational Sciences. – 2022. – Т. 1. – №. 11. – С. 241-245. 10. Nizametdinov, A. A. (2022). OLIY TA’LIM TIZIMINING AGRAR SOHASIDA
INNOVATSION
TEXNOLOGIYALAR
QOʻLLASH
USTUVORLIGI. INTERNATIONAL
CONFERENCES, 1(6),
58–60. Retrieved
from
https://researchedu.org/index.php/cf/article/view/96 10. Nizametdinov, A. A. (2022). OLIY TA’LIM TIZIMINING AGRAR SOHASIDA
INNOVATSION
TEXNOLOGIYALAR
QOʻLLASH
USTUVORLIGI. INTERNATIONAL
CONFERENCES, 1(6),
58–60. Retrieved
from
https://researchedu.org/index.php/cf/article/view/96 11. Nizametdinov A. et al. THE IMPORTANCE OF THE DIGITAL ECONOMY TODAY
//Journal of Academic Research and Trends in Educational Sciences. – 2022. – Т. 1. – №. 11. – С. 251-254. 11. Nizametdinov A. et al. THE IMPORTANCE OF THE DIGITAL ECONOMY TODAY
//Journal of Academic Research and Trends in Educational Sciences. – 2022. – Т. 1. – №. 11. – С. 251-254. 12. Akramovich N. A. et al. RAQAMLI IQTISODIYOTNI O’ZBEKISTONDAGI O’RNI
//Conferencea. – 2022. – С. 67-69. 12. Akramovich N. A. et al. RAQAMLI IQTISODIYOTNI O’ZBEKISTONDAGI O’RNI
//Conferencea. – 2022. – С. 67-69. 13. Xaydarov Baxrom Xolmuradovich, Xudayarov Rashid Tuychiyevich. (2022). RAQAMLI
IQTISODIYOT
BIZNESNI
REJALASHTIRISH. International
Journal
of
Contemporary Scientific and Technical Research, 1(2), 110–113. Retrieved from
http://journal.jbnuu.uz/index.php/ijcstr/article/view/130 14. Xaydarov Baxrom Xolmuradovich, & Saitov Sirojiddin Abduvalievich. (2022). RAQAMLI IQTISODIYOTDA KICHIK BIZNESNNING O‘RNI. International Journal of
Contemporary Scientific and Technical Research, 1(2), 113–116. Retrieved from
http://journal.jbnuu.uz/index.php/ijcstr/article/view/131 14. Xaydarov Baxrom Xolmuradovich, & Saitov Sirojiddin Abduvalievich. (2022). RAQAMLI IQTISODIYOTDA KICHIK BIZNESNNING O‘RNI. International Journal of
Contemporary Scientific and Technical Research, 1(2), 113–116. Retrieved from
http://journal.jbnuu.uz/index.php/ijcstr/article/view/131 15. Xaydarov Baxrom Xolmuradovich. (2022). RAQAMLI IQTISODIYOTDA
BUXGALTERIYA VA AUDITNI OʻRNI. International Journal of Contemporary Scientific and
Technical
Research,
1(2),
128–131. Retrieved
from
http://journal.jbnuu.uz/index.php/ijcstr/article/view/135 15. Xaydarov Baxrom Xolmuradovich. (2022). RAQAMLI IQTISODIYOTDA
BUXGALTERIYA VA AUDITNI OʻRNI. International Journal of Contemporary Scientific and
Technical
Research,
1(2),
128–131. Retrieved
from
http://journal.jbnuu.uz/index.php/ijcstr/article/view/135 16. Худаяров Р., Ахрор А. БОЛЬШИЕ ДАННЫЕ ТИПОВ СИСТЕМЫ
ОБРАЗОВАНИЯ И ВОЗМОЖНОСТИ ИХ ИСПОЛЬЗОВАНИЯ В ДАННОЙ ОБЛАСТИ //
Журнал академических исследований и тенденций в области педагогических наук. –
2022. – Т. 1. – No 4. – С. 21-24. 16. Худаяров Р., Ахрор А. БОЛЬШИЕ ДАННЫЕ ТИПОВ СИСТЕМЫ
ОБРАЗОВАНИЯ И ВОЗМОЖНОСТИ ИХ ИСПОЛЬЗОВАНИЯ В ДАННОЙ ОБЛАСТИ //
Журнал академических исследований и тенденций в области педагогических наук. –
2022. – Т. 1. – No 4. – С. 21-24. 17. Худояров Р. СОВЕРШЕНСТВОВАНИЕ ЭКОНОМИЧЕСКОГО УПРАВЛЕНИЯ В
УСЛОВИЯХ РЫНОЧНОЙ ЭКОНОМИКИ // Galaxy International Interdisciplinary Research
Journal. – 2022. – Т. 10. – No 2. – С. 610-612. 17. Худояров Р. СОВЕРШЕНСТВОВАНИЕ ЭКОНОМИЧЕСКОГО УПРАВЛЕНИЯ В
УСЛОВИЯХ РЫНОЧНОЙ ЭКОНОМИКИ // Galaxy International Interdisciplinary Research
Journal. – 2022. – Т. 10. – No 2. – С. 610-612. 76 Journal of Academic Research and Trends in Educational Sciences (JARTES)
VOLUME 1, ISSUE 12 / ISSN 2181-2675 18. Akramovich N. A. THE PRIORITY OF USING INNOVATIVE TECHNOLOGIES IN
THE AGRICULTURAL EDUCATION SYSTEM //Journal of Academic Research and Trends in
Educational Sciences. – 2022. – Т. 1. – №. 10. – С. 185-191. 18. Akramovich N. A. THE PRIORITY OF USING INNOVATIVE TECHNOLOGIES IN
THE AGRICULTURAL EDUCATION SYSTEM //Journal of Academic Research and Trends in
Educational Sciences. – 2022. – Т. 1. – №. 10. – С. 185-191. 19. Nizametdinov
А.,
Аhmedova
H. Elektron
ta
‘lim
metodologiyasi
rivojlantirishning usullari //Zamonaviy innovatsion tadqiqotlarning dolzarb muammolari
va rivojlanish tendensiyalari: yechimlar va istiqbollar. – 2022. – Т. 1. – №. 1. – С. 29-31. 19. Nizametdinov
А.,
Аhmedova
H. Elektron
ta
‘lim
metodologiyasi
rivojlantirishning usullari //Zamonaviy innovatsion tadqiqotlarning dolzarb muammolari
va rivojlanish tendensiyalari: yechimlar va istiqbollar. – 2022. – Т. 1. – №. 1. – С. 29-31. 20. Nizametdinov, A. A. (2022). OLIY TA’LIM TIZIMIDA AGRAR SOHANING
USTUVORLIGI
UNDA
INNOVATSIYALARNING
QULLANISHI. INTERNATIONAL
CONFERENCES, 1(6),
96–98. Retrieved
from
https://researchedu.org/index.php/cf/article/view/104 20. Nizametdinov, A. A. (2022). OLIY TA’LIM TIZIMIDA AGRAR SOHANING
USTUVORLIGI
UNDA
INNOVATSIYALARNING
QULLANISHI. INTERNATIONAL
CONFERENCES, 1(6),
96–98. Retrieved
from
https://researchedu.org/index.php/cf/article/view/104 21. Nizametdinov Ali Akramovich. (2022). SUN’IY INTELEKTNI KADRLAR
SIYOSATINI RIVOJLANTIRISHDAGI AHAMIYATI. International Journal of Contemporary
Scientific
and
Technical
Research, 1(2),
251–253. Retrieved
from
http://journal.jbnuu.uz/index.php/ijcstr/article/view/171 22. Sirojiddin S., Azizbek A. TRANSITION TO THE MARKET ECONOMY AND ITS
CHARACTERISTICS IN UZBEKISTAN //Journal of Academic Research and Trends in
Educational Sciences. – 2022. – Т. 1. – №. 11. – С. 255-258. 23. Nodira T., Sirojiddin S., Azizbek Z. SOCIO-ECONOMIC SYSTEMS //Journal of
Academic Research and Trends in Educational Sciences. – 2022. – Т. 1. – №. 11. – С. 260-
264. 24. Sirojiddin S., Nodira T., Dinora S. CHARACTERISTICS OF PRICE AND
FORMATION //Journal of Academic Research and Trends in Educational Sciences. – 2022. –
Т. 1. – №. 11. – С. 265-270. 25. Nodira T. INNOVATIVE MANAGEMENT IN THE DEVELOPMENT OF THE
HIGHER EDUCATION SYSTEM //Journal of Academic Research and Trends in Educational
Sciences. – 2022. – Т. 1. – №. 10. – С. 346-351. 26. Nodira T., Rashid X. PROBLEMS OF INNOVATION MANAGEMENT IN THE
HIGHER EDUCATION SYSTEM //Web of Scientist: International Scientific Research Journal. – 2022. – Т. 3. – №. 11. – С. 155-164. 27. Toʻychiyeva N. AGRAR SOHADA TADBIRKORLIK FAOLIYATINI TASHKIL
ETISHGA TA’SIR ETUVCHI OMILLAR //INTERNATIONAL CONFERENCES. – 2022. – Т. 1. –
№. 4. – С. 53-56. 28. To‘ychiyeva N. AGRAR TARMOQDA TADBIRKORLIK FAOLIYATINI TASHKIL
ETISHNING TASHKILIY-IQTISODIY ASOSLARI //INTERNATIONAL CONFERENCES. – 2022. – Т. 1. – №. 4. – С. 3-6. 28. To‘ychiyeva N. AGRAR TARMOQDA TADBIRKORLIK FAOLIYATINI TASHKIL
ETISHNING TASHKILIY-IQTISODIY ASOSLARI //INTERNATIONAL CONFERENCES. – 2022. – Т. 1. – №. 4. – С. 3-6. 29. Nodira T., Maxfirat T. FOREIGN LANGUAGE PRONUNCIATION IN GRADES 1-4»
//РЕДАКЦИОННАЯ КОЛЛЕГИЯ. – С. 1133. 29. Nodira T., Maxfirat T. FOREIGN LANGUAGE PRONUNCIATION IN GRADES 1-4»
//РЕДАКЦИОННАЯ КОЛЛЕГИЯ. – С. 1133. //
30. Toʻychiyeva
N. THE
MAIN
CHARACTERISTICS
OF
INNOVATION
MANAGEMENT IN THE HIGHER EDUCATION SYSTEM //INTERNATIONAL CONFERENCES. – 2022. – Т. 1. – №. 6. – С. 103-105. 30. Toʻychiyeva
N. THE
MAIN
CHARACTERISTICS
OF
INNOVATION
MANAGEMENT IN THE HIGHER EDUCATION SYSTEM //INTERNATIONAL CONFERENCES. – 2022. – Т. 1. – №. 6. – С. 103-105. 77
|
https://openalex.org/W2480562997
|
https://escholarship.org/content/qt9rw9b5tj/qt9rw9b5tj.pdf?t=qgcq3w
|
English
| null |
Predation on Fishes in the Sacramento-San Joaquin Delta: Current Knowledge and Future Directions
|
San Francisco estuary and watershed science
| 2,016
|
cc-by
| 15,913
|
UC Davis
San Francisco Estuary and Watershed Science
Title
Predation on Fishes in the Sacramento–San Joaquin Delta: Current Knowledge and Future
Directions
Permalink
https://escholarship.org/uc/item/9rw9b5tj
Journal
San Francisco Estuary and Watershed Science, 14(2)
Author
Grossman, Gary D.
Publication Date
2016
DOI
https://doi.org/10.15447/sfews.2016v14iss2art8
Copyright Information
Copyright 2016 by the author(s).This work is made available under the terms of a Creative
Commons Attribution License, available at https://creativecommons.org/licenses/by/4.0/
Peer reviewed UC Davis
San Francisco Estuary and Watershed Science
Title
Predation on Fishes in the Sacramento–San Joaquin Delta: Current Knowledge and Future
Directions
Permalink
https://escholarship.org/uc/item/9rw9b5tj
Journal
San Francisco Estuary and Watershed Science, 14(2)
Author
Grossman, Gary D. Publication Date
2016
DOI
https://doi.org/10.15447/sfews.2016v14iss2art8
Copyright Information
Copyright 2016 by the author(s).This work is made available under the terms of a Creative
Commons Attribution License, available at https://creativecommons.org/licenses/by/4.0/
Peer reviewed UC Davis
San Francisco Estuary and Watershed Science
Title
Predation on Fishes in the Sacramento–San Joaquin Delta: Current Knowledge and Future
Directions
Permalink
https://escholarship.org/uc/item/9rw9b5tj
Journal
San Francisco Estuary and Watershed Science, 14(2)
Author
Grossman, Gary D. Publication Date
2016
DOI
https://doi.org/10.15447/sfews.2016v14iss2art8
Copyright Information
Copyright 2016 by the author(s).This work is made available under the terms of a Creative
Commons Attribution License, available at https://creativecommons.org/licenses/by/4.0/
Peer reviewed Errata: Grossman (2016)
SAN FRANCISCO ESTUARY AND WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 | JULY 2016 Powered by the California Digital Library
University of California eScholarship.org REVISED NOVEMBER 2016 SPECIAL ISSUE: THE STATE OF BAY–DELTA SCIENCE 2016, PART 1 Volume 14, Issue 2 | Article 8 Volume 14, Issue 2 | Article 8
doi: http://dx.doi.org/10.15447/sfews.2016v14iss2art8 1 Warnell School of Forestry and Natural Resources
University of Georgia, Athens, GA 90602 USA
grossman@uga.edu 1 Warnell School of Forestry and Natural Resources
University of Georgia, Athens, GA 90602 USA
grossman@uga.edu ABSTRACT The Sacramento–San Joaquin Delta (Delta) is a
heterogeneous, highly modified aquatic system. I reviewed relevant predator–prey theory, and
described extant data on predator–prey relationships
of Delta fishes. I ranked predator consumption rates
as occasional, moderate, and common, based on
frequency-of-occurrence data, and evaluated the
frequency, and hypothesized the effects of predation
on native and invasive species. I identified 32
different predator categories and 41 different prey
categories. Most predators were occasional consumers
of individual prey species, although I also observed
moderate and common consumption of some prey
types. My analysis yielded few generalizations
regarding predator–prey interactions for Delta
fishes; most predators consumed a variety of both
native and invasive fishes. The only evidence for
predator specialization on either native or invasive
fishes occurred in Prickly Sculpin which, when it
consumed fishes, ate mostly native species. Both Predation on Fishes in the Sacramento–San Joaquin Delta:
Current Knowledge and Future Directions Gary D. Grossman1 Volume 14, Issue 2 | Article 8
doi: http://dx.doi.org/10.15447/sfews.2016v14iss2art8 Volume 14, Issue 2 | Article 8 Volume 14, Issue 2 | Article 8
doi: http://dx.doi.org/10.15447/sfews.2016v14iss2art8 1 Warnell School of Forestry and Natural Resources
University of Georgia, Athens, GA 90602 USA
grossman@uga.edu 1 Warnell School of Forestry and Natural Resources
University of Georgia, Athens, GA 90602 USA
grossman@uga.edu 1 Warnell School of Forestry and Natural Resources
University of Georgia, Athens, GA 90602 USA
grossman@uga.edu Several small errors have been discovered in
Table 2 of Predation on Fishes in the Sacramento–
San Joaquin Delta: Current Knowledge and Future
Directions, published in Volume 14, Issue 2 of
the online journal San Francisco Estuary and
Watershed Science. These errors do not affect any
conclusions made in the paper and are as follows:
for predatory Sacramento Pikeminnow the prey
classification of Longfin Smelt should go from C to
M, and for Mississippi Silversides, Smallmouth Bass,
and Threadfin Shad the prey classification should
be reduced from M to O. For predatory Largemouth
Bass, the classifications of both Smallmouth Bass
and Sacramento Pikeminnow should switch from
C to M. For predatory Smallmouth bass the prey
classification of Chinook Salmon should be lowered
from C to M and finally, predatory White Catfish
consumed Smallmouth Bass with a frequency of O
rather than M. i http://dx.doi.org/10.15447/sfews.2015v14iss2art8 This page is intentionally left blank. JULY 2016 Predation on Fishes in the Sacramento–San Joaquin Delta:
Current Knowledge and Future Directions Gary D. Grossman1 Striped and Largemouth Bass exhibited wide dietary
breadth, preying upon 32 and 28 categories of
fish prey respectively. Sacramento Pikeminnow, a
native predator, also displayed wide dietary breadth
of piscine prey, with 14 different prey categories
consumed. Data for reptilian, avian, and mammalian
predators were sparse; however, these predators may
be significant fish predators in altered habitats or
when hatchery salmonids are released. The database
for predators and their fish prey was not strong, and I
recommend long-term dietary studies combined with
prey availability and behavioral and experimental
studies to establish predator preferences and anti-
predator behaviors, rather than just consumption. The behavioral effects of contaminants on prey
species also warrant further examination. Although
it has been suggested that a reduction in the Striped
Bass population be implemented to reduce predation
mortality of Chinook Salmon, the large number of
salmon predators in the Delta make it unlikely that
this effort will significantly affect salmon mortality. INTRODUCTION The Sacramento–San Joaquin Delta (the Delta) is the
eastern portion of the largest estuarine system on the
West Coast of the Americas (San Francisco Estuary),
encompassing an area of 3,238 km2 (Whipple et al. 2012). This system provides critical habitat for plants
and animals with over 700 species recorded, as well
as providing irrigation water to farms in the highly
productive Sacramento and San Joaquin valleys. In
the last 150 years, human effects on the Delta include
a variety of environmental changes (DSC 2013;
Wiens et al. 2016) including: The Sacramento–San Joaquin Delta (the Delta) is the
eastern portion of the largest estuarine system on the 1. physical (channelization, flow control, water
export), 2. chemical (discharge of toxins, nutrients), and 3. biological (species invasions, conversion of
floodplain to agriculture) characteristics, most
of which have produced declines in habitat
quality for native species. KEY WORDS Delta Smelt, Longfin Smelt, Chinook Salmon,
Rainbow Trout, Striped Bass, Largemouth Bass,
Pikeminnow, predator–prey interactions SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 modified aquatic system (Kimmerer et al. 2008;
Dettinger et al., submitted; Luoma et al. 2015), it is
a challenge to quantify the true effect of predation
on fishes, given the ubiquity of co-varying factors
(e.g., habitat degradation) capable of negatively
affecting fish populations (Grossman et al. 2013;
Wiens et al 2016). In this paper, I describe relevant
predator–prey theory, and potential predator–prey
interactions among resident predators and fish
prey. Unfortunately, there is scant information on
the interactions between predators and prey in the
Delta; consequently, my main source of information
comes from dietary studies of predatory fishes. This information includes the published scientific
and selected gray literature references, as well as
presentations at the 2013 Fish Predation Workshop
(http://www.dfg.ca.gov/erp/predation.asp) and 2015
Interagency Ecological Program Workshop (http://
www.water.ca.gov/iep/activities/workshop_events. cfm). THE DYNAMICS OF PREDATION ON
FISH POPULATIONS Because the Delta is a heterogeneous, highly 2 JULY 2016 JULY 2016 and (3) assessment of the role of predation in the
regulation of prey abundance. Grossman et al. (2013) discuss the potential methods for approaching
predation-effect studies for fish predators and
salmonid prey that inhabit the Delta. inputs, combined with water abstraction may alter
flow patterns, especially in the east and south Delta
(Kimmerer et al. 2008; Dettinger et al., submitted;
Luoma et al. 2015). This may confuse prey species
and shift their movements and migratory pathways
in a manner that keeps them in greater contact
with potential predators (Winder et al. 2011; Cloern
and Jassby 2012). In this case, predation may be
the proximate cause of mortality, whereas altered
flow regimes are the ultimate cause. Clearly, the
classification of mechanisms as either ultimate
or proximate causes of mortality is an over-
simplification, and the point at which a process
moves from merely being an “influence” to a
proximate cause, and, finally, an ultimate cause
of mortality is typically unknown and, even when
known, frequently subject to debate. Despite the difficulty of the task, scientists and
managers may require information on how predators
affect fish populations, which, in addition to the
factors listed above, requires: (1) accurate and precise
estimates of predator and prey abundance, and
(2) numerical and proportional estimates of predation
mortality on the prey population or for a particular
life-history stage (e.g., eggs, fry, and juveniles). Quantifying these parameters is both logistically and
methodologically difficult, and obtaining estimates
with reasonable accuracy and precision requires
replication in space and time. For example, providing
accurate data for step two requires experiments
quantifying the functional and numerical responses
of important predators on fish, coupled with annual
and seasonal estimates of prey abundance and
productivity (Grossman et al. 2013). Although this
will produce an estimate of mortality attributable
to predation, the estimate then must be compared
to other sources of mortality (e.g., disease) to
determine whether predators contribute significantly
to population mortality through time. In the Delta,
mortality from predation is just one of many
potential sources of mortality, including: entrainment
by water abstraction facilities, physiological stress,
contaminants, food limitation, disease, and parasites,
all of which may interact. Finally, mortality may
be compensatory such that an increase in predation
mortality may be offset by a decrease in disease
mortality, with the overall mortality rate remaining
constant. THE DYNAMICS OF PREDATION ON
FISH POPULATIONS These decreases in habitat quality in concert with
the effects of introduced species, are linked to major
declines in formerly abundant native species such
as Chinook Salmon (Oncorhynchus tshawytscha),
Steelhead (Oncorhynchus mykiss), Delta Smelt
and Longfin Smelt (Hypomesus transpacificus and
Spirinchus thaleichthys, respectively), the extinction
of the Thicktail Chub (Gila crassicauda), and the
local extinction of the Sacramento Perch (Archoplites
interruptus). Population declines have not just
occurred in native species; both Striped Bass (Morone
saxatilis) and Threadfin Shad (Dorosoma petenense)
display recent decreases in abundance (Sommer et al. 2007). How predation effects a fish population may be
examined at varying levels of resolution, ranging
from quantification of the frequencies, numbers,
masses or volumes of prey species in gut contents,
to estimates of the number of prey consumed per
predator per day, to estimates of the proportion of
the prey population consumed by each predator
over a given time interval (day, month, season). The level of precision required to quantify predator
effects depends on the question being posed. At
the most basic level, gut content information tells
us that a given predator consumes a given prey
species, but yields limited information on the effects
of predation on the prey species. Alternatively, lab
experiments with a single predator and prey species
yield information on the behavioral interactions of
the species pair, but cannot tell us how the predator
will behave in the presence of alternate prey or
in “natural habitats.” The most detailed level of
predator-prey studies involves quantification of the
effects of a given predator on prey abundance and
survivorship and requires measurement of multiple
factors including: (1) the amount of predation
mortality experienced by a prey population over
time, (2) ultimate and proximate causes of mortality, There are few data on either the historic or current
effects of predators on the abundance, size, structure,
and dynamics of Delta fish populations. Nonetheless,
it is clear that native and invasive (I use the term
invasive because it accurately represents the fact that
these species have invaded a habitat) prey species run
a gauntlet of potential predators including invasive
predatory fishes (Striped Bass, centrarchids, percids
and ictalurids), native and introduced snakes and
amphibians (garter snakes and bullfrogs), mammals
(North American river otter Lontra canadensis),
and birds (herons egrets terns and gulls) (Draulans and birds (herons, egrets, terns and gulls) (Draulans
1988). THE DYNAMICS OF PREDATION ON
FISH POPULATIONS Because of the presence of compensatory
processes in many fish populations (Grossman et
al. 2006, 2012), quantifying the direct effects of
predation on the total mortality rate of a population
is difficult, at best (Kerfoot and Sih 1987). It is reasonable to assume, however, that some
anthropogenic factors, especially contaminants
known to affect fish behavior, are likely to be the
ultimate cause of a significant amount of predation
mortality for Delta fishes. Much more research is
needed on the behavioral effects of contaminants
on Delta fishes, because little is known about these
effects (but see Connon et al. 2009, 2011; McIntyre
et al. 2008, 2012). There are some extant data for
other related species and these likely can be use to
gain insights on predator–prey interactions of Delta
fishes. The contaminant load of the Delta is likely
substantial and includes the following potentially
bioactive agents: pesticides, pharmaceuticals and
personal care products (e.g., psychcoactive drugs
and triclosan), estrogen disruptors, ammonia,
metalloids such as selenium, and heavy metals
such as mercury, copper, and aluminum. These
contaminants are all are present in concentrations
that could affect fish behavior (Sloman and Wilcox
2006; Connon et al. 2011; Brooks et al 2012; Fong
et al., submitted). Aluminum, in particular, affects
physiological homeostasis as well as learning and
behavioral performance in Atlantic Salmon (Salmo
salar, Grassie et al. 2013). Similarly, Sandahl et
al. (2007) demonstrates that copper concentrations
commonly found in Delta waters can produce
abnormal anti-predator behaviors in Coho Salmon
(Oncorhynchus kisutch). Their video (http://pubs.acs. org/doi/suppl/10.1021/es062287r; see page 2) shows
control salmon ceasing movement and dropping to
the bottom of the tank when exposed to a fright It is reasonable to assume, however, that some
anthropogenic factors, especially contaminants
known to affect fish behavior, are likely to be the
ultimate cause of a significant amount of predation
mortality for Delta fishes. Much more research is
needed on the behavioral effects of contaminants
on Delta fishes, because little is known about these
effects (but see Connon et al. 2009, 2011; McIntyre
et al. 2008, 2012). There are some extant data for
other related species and these likely can be use to
gain insights on predator–prey interactions of Delta
fishes. THE DYNAMICS OF PREDATION ON
FISH POPULATIONS Figure 1 A schematic depicting the components of predation
and factors that affect predation in the Delta. “Search and
Encounter” refers to the activities involved in locating prey,
“Pursuit and Attack” to drawing close to the prey and initiating
capture, ”Capture” to the physical capture of the prey, and
“Handling” to the physical act of manipulating the prey for
consumption. The factors in the black boxes represent factors
in unmodified environments that affect the predation process. The factors in underlined gray italics represent anthropogenic
environmental changes in the Delta that increase predation rates
on fishes. Figure 1 A schematic depicting the components of predation
and factors that affect predation in the Delta. “Search and
Encounter” refers to the activities involved in locating prey,
“Pursuit and Attack” to drawing close to the prey and initiating
capture, ”Capture” to the physical capture of the prey, and
“Handling” to the physical act of manipulating the prey for
consumption. The factors in the black boxes represent factors
in unmodified environments that affect the predation process. The factors in underlined gray italics represent anthropogenic
environmental changes in the Delta that increase predation rates
on fishes. and Cech 2004). All else being equal, foraging
theory predicts that predators will choose prey that
maximize their net energy gain (Grossman 2014),
although this can be achieved through a variety
of methods. It is likely that Delta predators prefer
fish prey that are energy-rich (Hartman and Brandt
1995), easily handled and consumed (i.e., small, soft-
rayed and fusiform) and naïve to invasive predators
(Kuehne and Olden 2012; Carthey and Banks
2014). Several authors document the importance
of behavioral naiveté to predation mortality by
demonstrating that invasive Lake Trout and Northern
Pike feed disproportionately on salmonids despite the
apparently higher abundance of native catostomid
prey (Johnson and Martinez 2000; Johnson et al. 2002; Lepak et al. 2012). Given that the majority of
fish predators in the Delta are invasives (Table 1),
native fishes in the Delta may suffer increased
predation because a lack of shared evolutionary
history could produce predator naiveté in prey species
(reviewed by Carthy and Banks 2014). Nonetheless,
it is also true that some invasive predators have THE DYNAMICS OF PREDATION ON
FISH POPULATIONS The contaminant load of the Delta is likely
substantial and includes the following potentially
bioactive agents: pesticides, pharmaceuticals and
personal care products (e.g., psychcoactive drugs
and triclosan), estrogen disruptors, ammonia, g
p
metalloids such as selenium, and heavy metals
such as mercury, copper, and aluminum. These
contaminants are all are present in concentrations
that could affect fish behavior (Sloman and Wilcox
2006; Connon et al. 2011; Brooks et al 2012; Fong
et al., submitted). Aluminum, in particular, affects
physiological homeostasis as well as learning and
behavioral performance in Atlantic Salmon (Salmo
salar, Grassie et al. 2013). Similarly, Sandahl et
al. (2007) demonstrates that copper concentrations
commonly found in Delta waters can produce
abnormal anti-predator behaviors in Coho Salmon
(Oncorhynchus kisutch). Their video (http://pubs.acs. org/doi/suppl/10.1021/es062287r; see page 2) shows
control salmon ceasing movement and dropping to
the bottom of the tank when exposed to a fright The ultimate goal of predation studies is to quantify
the importance of predator–prey relationships on
both the dynamics of populations and the behavior
of individuals. However, predation may be either
the proximate or the ultimate cause of individual
mortality, and identifying which of these two
processes is operating may be problematical. In the
Delta, decreased and altered timing of freshwater http://dx.doi.org/10.15447/sfews.2015v14iss2art8 3 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 f (reduced spatial herogeneity,
reduced/reversed flows, structural
modifications, contaminants
invasive predators/plants)
Search and
Encounter
Pursuit and
Attack
Capture and
Handling
Consumption
f (prey abundance, spatial and
temporal overlap, encounter rate,
& behavior)
Figure 1 A schematic depicting the components of predation
and factors that affect predation in the Delta. “Search and
Encounter” refers to the activities involved in locating prey,
“Pursuit and Attack” to drawing close to the prey and initiating
capture, ”Capture” to the physical capture of the prey, and
“Handling” to the physical act of manipulating the prey for
consumption. The factors in the black boxes represent factors
in unmodified environments that affect the predation process. The factors in underlined gray italics represent anthropogenic
environmental changes in the Delta that increase predation rates
on fishes. THE DYNAMICS OF PREDATION ON
FISH POPULATIONS f (reduced spatial herogeneity,
reduced/reversed flows, structural
modifications, contaminants
invasive predators/plants)
Search and
Encounter
Pursuit and
Attack
Capture and
Handling
Consumption
f (prey abundance, spatial and
temporal overlap, encounter rate,
& behavior) f (reduced spatial herogeneity,
reduced/reversed flows, structural
modifications, contaminants
invasive predators/plants)
Search and
Encounter
Pursuit and
Attack
Capture and
Handling
Consumption
f (prey abundance, spatial and
temporal overlap, encounter rate,
& behavior) stimulus, whereas fish exposed to copper continue
moving around the tank in an agitated and highly
visible manner, that almost certainly renders them
more susceptible to predation. f (prey abundance, spatial and
temporal overlap, encounter rate,
& behavior) Search and
Encounter Sloman and Wilcox (2006) reviewed the literature
on the relationship between chemical contaminants
and behavior of both prey and predator, and
concluded that chemicals significantly impaired
anti-predator behavior of multiple prey species
including salmonids, cyprinids, cyprinodontids,
poeciliids and gasterosteids; findings supported
by more recent studies that examined European
perch (Perca fluviatilis, Brodin et al. 2013) coho
salmon (Oncorhynchus kisutch, McIntire et al. 2008,
2012) and fathead minnows (Pimephales promelas,
Fritsch et al. 2013). Consequently, it seems clear
that contaminants can be the ultimate cause of
mortality for prey fishes in the Delta, although this
conclusion is complicated by the fact that some of
the same compounds that disorient prey also inhibit
the foraging behavior of predators (Sloman and
Wilcox 2006). Finally, McGourty et al. (2009) found
that Longjaw Mudsuckers (Gillichthys mirabilis) from
San Francisco Bay displayed higher contaminant
burdens and mortality rates, lower growth rates,
and lower adult abundances, than individuals of the
same species from the relatively contaminant-free
Tomales Bay. The current status of contaminants in
the Delta is reviewed in Fong et al. (submitted) and
Schoellhamer et al. (submitted). Pursuit and
Attack Capture and
Handling Consumption Figure 1 A schematic depicting the components of predation
and factors that affect predation in the Delta. “Search and
Encounter” refers to the activities involved in locating prey,
“Pursuit and Attack” to drawing close to the prey and initiating
capture, ”Capture” to the physical capture of the prey, and
“Handling” to the physical act of manipulating the prey for
consumption. The factors in the black boxes represent factors
in unmodified environments that affect the predation process. The factors in underlined gray italics represent anthropogenic
environmental changes in the Delta that increase predation rates
on fishes. a. Effectively extinct from the Delta. Components of the Predation Process The act of predation may be broken into several
component rates, including search and encounter,
pursuit and attack, capture and handling, and
consumption, and these components are affected
by a variety of changes that have occurred in the
Delta (Figure 1). In unmodified environments, these
components are affected by factors such as prey
abundance and availability, spatial and temporal
overlap of predator and prey, habitat complexity,
turbidity, behavior, physiology, and morphological
adaptations that facilitate (predator) or inhibit (prey)
the predation process. Although most fish predators
are opportunistic feeders (Gerking 1994), differences
in prey characteristics (e.g., morphology, behavior,
and energy content) also affect prey choice (Moyle 4 JULY 2016 JULY 2016 Table 1 Native and invasive fishes in the Sacramento–San Joaquin Delta system. Uncommon species are included, although primary marine
and estuarine fishes that occasionally enter the Delta are not. Piscivores are marked in bold and the names of predators that may prey on
fishes for some portion of their lifespan or when periodically available are underlined. Table 1 Native and invasive fishes in the Sacramento–San Joaquin Delta system. Uncommon species are included, although primary marine
and estuarine fishes that occasionally enter the Delta are not. Piscivores are marked in bold and the names of predators that may prey on
fishes for some portion of their lifespan or when periodically available are underlined. Native species
common name
Scientific name
Invasive species
common name
Scientific name
Chinook Salmon
Oncorhynchus tshawytscha
American Shad
Alosa sapidissima
Delta Smelt
Hypomesus transpacificus
Bigscale Logperch
Percina macrocephalus
Green Sturgeon
Acipenser medirostris
Black Bullhead
Ameiurus melas
Hardhead
Mylopharodon conocephalus
Black Crappie
Pomoxis nigromaculatus
Longfin Smelt
Spirinchus thaleichthys
Blue Catfish
Ictalurus furcatus
Pacific Lamprey
Entosphenus tridentatus
Bluegill
Lepomis macrochirus
Prickly Sculpin
Cottus asper
Brown Bullhead
Ameiurus nebulosus
River Lamprey
Lampetra ayresi
Common Carp
Cyprinus carpio
Steelhead
Oncorhynchus mykiss
Channel Catfish
Ictalurus punctatus
Sacramento Hitch
Lavinia exilicauda
Fathead Minnow
Pimephales promelas
Sacramento Splittail
Pogonichthys macrolepidotus
Green Sunfish
Lepomis cyanellus
Sacramento Pikeminnow
Ptychocheilus grandis
Goldfish
Carassius aurata
Sacramento Blackfish
Orthodon microlepidotus
Golden Shiner
Notemogonis chrysoleucus
Sacramento Percha
Archoplites interruptus
Largemouth Bass
Micropterus salmoides
Threespine Stickleback
Gasterosteus aculeatus
Mississippi Silverside
Menidia beryllina
Tule Perch
Hysterocarpus traskii
Rainwater Killifish
Lucania parva
White Sturgeon
Acipenser transmontanus
Red Shiner
Cyprinella lutrensis
Redear Sunfish
Lepomis microlophus
Redeye Bass
Micropterus coosae
Smallmouth Bass
Micropterus dolomieu
Shimofuri Goby
Tridentiger bifasciatus
Shokihaze Goby
Tridentiger barbatus
Spotted Bass
Micropterus punctulatus
Striped Bass
Morone saxatilis
Threadfin Shad
Dorosoma petense
Wakasagi
Hypomesus nipponensis
Warmouth
Lepomis gulosus
Western Mosquitofish
Gambusia affinis
White Catfish
Ameiurus catus
White Crappie
Pomoxis annularis
Yellowfin Goby
Acanthagobius flavimanus
a. Effectively extinct from the Delta. 5 http://dx.doi.org/10.15447/sfews.2015v14iss2art8 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 and predator, as well as different effects on roving
predators (i.e., Striped Bass) versus ambush predators
(i.e., Largemouth Bass). been established in the Delta for over 100 years (e.g.,
Striped Bass) and it is possible that prey species have
had sufficient time to develop behavioral adaptations
to these predators. The study of predator–prey dynamics in fishes is
complicated by the fact that almost all fishes display
ontogenetic dietary niches. JULY 2016 The majority of fishes
are micro-carnivores when young and then may
transition through the macro-invertivore and finally
to the piscivore stage. In addition, even herbivores
may be sufficiently opportunistic to take advantage
of periodically abundant high-energy prey, such as
fish eggs or fry, and the population-level effects of
this predation are largely unknown. If a predator
is piscivorous, however, its effect on prey may
be sublethal or indirect. For example, introduced
Largemouth Bass almost extirpated cyprinids from
Wisconsin lakes, by forcing cyprinids to shift
from high-quality littoral areas to low-quality
pelagic microhabitats with high temperatures, low
food abundance, and abundant avian predators
(Carpenter and Kitchell 1993). In other cases,
behavioral avoidance of multiple predators may
produce multiplicative effects, where the effect of
one predator enhances the efficiency of a second
predator (Hixon and Carr 1997). An hypothetical but
not unlikely example for the Delta involves Striped
Bass preying on native species such as hitch (Lavinia
exilicauda) or Sacramento Blackfish (Orthodon
microlepidotus) in open water habitats. To avoid The effects of both contaminants and invasive species
may be magnified by environmental changes that
have occurred in the Delta over the last 100 years
including: (1) species invasions that alter physical
habitat structure, (2) alterations of hydrologic
regimes, temperature regimes and turbidity levels,
(3) wetland loss, and (4) anthropogenic changes in
physical structure (levees, canals, and abstraction
facilities), coupled with changes in climate (Cloern
and Jassby 2012; Dettinger et al., submitted). Predation on Delta fishes also is affected by
ecosystem-level effects of invasives, such as the
shift in the food web produced by the non-predatory
overbite clam (Corbula amurensis, Cloern and Jassby
2012, Brown et al., forthcoming) or changes in the
structural complexity of littoral habitats produced
by invasive submerged aquatic macrophytes such as
Egeria (Brown et al. 2016, forthcoming; Conrad et al. 2016). The increase in littoral structural complexity
favors invasive species that currently inhabit the
Delta, although it may also provide refuge for some
prey species. The Context-Dependency of Predation Striped Bass, an individual of these species might
find refuge in submerged aquatic vegetation (SAV),
the preferred habitat of centrarchids and ictalurids,
and then be eaten by one of these invasives. Predation is almost always context-dependent;
meaning the effects of predators on both individual
prey and their populations vary based on the spatial
and temporal context of the interaction. For example,
predator–prey relationships in the Delta likely differ
substantially in drought versus high-flow years. Linking context-dependency to spatial heterogeneity
in the Delta means simply that the predation rate
of Least Terns on Delta Smelt in the Sacramento
River channel will likely differ from the predation
rate of the same predator and prey at the same
abundances in Franks Tract. An additional aspect
of spatial context-dependency in the Delta involves
the presence of predation hot spots where physical
conditions combine to make predation much more
likely than in unaltered habitats. Grossman et al. (2013) identified 13 predation hot-spots in the Delta
based on data from the Bay–Delta Conservation Plan
(BDCP 2013) and the California Fish and Wildlife Fish
Predation Workshop (2013), (i.e., mortality data from
tagged fish and flow alterations that likely would
shift fish out of their normal migration path into
low-quality habitat). Grossman et al. (2013) identified
the following hot spots: Predation is almost always context-dependent;
meaning the effects of predators on both individual
prey and their populations vary based on the spatial
and temporal context of the interaction. For example,
predator–prey relationships in the Delta likely differ
substantially in drought versus high-flow years. Estimating the effects of predators on prey
populations generally requires quantification of
functional and numerical responses of predators to
prey. The functional response describes the per-capita
feeding rate of predators, usually as a function of
prey density. An example of a functional response
would be measurement of how the per capita
predation rate of striped or Largemouth Bass on
Chinook Salmon changed as the abundance of smolts
changed during the outmigration. Most predatory
fishes display a Type III functional response, which
is “s” shaped and allows for both learning and
compensatory responses to predation. However, if
a functional response becomes asymptotic as prey
density increases (e.g., a Type II functional response)
depensatory mortality and population instability may
occur (Essington and Hansson 2004). The numerical
response details how changes in prey abundance
affect predator abundance. JULY 2016 Figure 2 illustrates the complexity of
predator-fish prey interactions as potentially affected
by invasions from introduced macrophytes where
increases in vegetation have different effects on prey Search and
Encounter
Pursuit and
Attack
Capture and
Handling
Consumption
efficiency
ambushers
efficiency rovers Ambush predators
Roving predators
Detection
~ = Detection
Avoidance
Avoidance
Predation
Predation
Search and
Encounter
Pursuit and
Attack
Capture and
Handling
Consumption
efficiency
ambushers
efficiency rovers
Figure 2 Figure 2 illustrates the potential complexity of how predators and prey respond behaviorally to environmental changes (e.g.,
submerged aquatic vegetation, SAV) in the Delta. (A) illustrates potential effects on ambush (Largemouth Bass) and roving (Striped Bass)
predators and their ability to capture prey. (B) displays the potential effects of how prey respond to ambush and roving predators and their
mortality rate. Components in gray italics represent processes that will decrease predation in the presence of SAV, whereas those in black
will increase predation in the presence of SAV. Roving predators
~ = Detection
Avoidance
Predation Ambush predators
Detection
Avoidance
Predation Consumption Figure 2 Figure 2 illustrates the potential complexity of how predators and prey respond behaviorally to environmental changes (e.g.,
submerged aquatic vegetation, SAV) in the Delta. (A) illustrates potential effects on ambush (Largemouth Bass) and roving (Striped Bass)
predators and their ability to capture prey. (B) displays the potential effects of how prey respond to ambush and roving predators and their
mortality rate. Components in gray italics represent processes that will decrease predation in the presence of SAV, whereas those in black
will increase predation in the presence of SAV. 6 JULY 2016 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 and sport fishes. The following case studies illustrate
the breadth of approaches and their efficacy in
controlling predatory fishes. District Dam on the Mokelumne River also may be
a predation hot spot, as well as the Tuolomne River
below Don Pedro Dam (FISHBIO 2013). Many other factors will induce variation into
predator–prey relationships including: (1) the
presence and type of shelter (e.g., SAV or woody
debris) (Conrad 2016), (2) the ratio of prey size to
predator size, (3) seasonal changes in abundance
of the prey array, (4) defensive morphological (e.g.,
spines) or behavioral adaptations (Mittelbach and
Persson 1998; Scharf et al. 2000), and (5) seasonal
changes in habitat quality for prey, such as those
produced by influxes of contaminants during winter–
spring high flows or high water temperatures during
summer and fall. Most predators are gape limited,
which means that larger individuals and species are
exposed to fewer predators than smaller individuals
and species. Hence, environmental conditions that
increase growth rates of prey such as favorable
water temperatures, and increases in habitat and
food quantity and quality, have a direct effect on
predation rates. Predator foraging tactics also change
depending on the array of prey available; hence,
predator–prey relationships cannot be viewed as
static entities. One of the most widespread and effective predator
control programs has been directed at Sea Lamprey
Petromyzon marinus in the Great Lakes (Smith and
Tibbles 1980; Larson et al. 2003). Application of the
highly selective lampricide TFM (3-trifluoromethyl-4-
nitrophenol) in rearing streams has been effective at
reducing Sea Lamprey populations by 90% in most
areas (Adair and Sullivan 2013) at a cost of about
$16 million per year (MDNR 2013). Lamprey control
probably has been successful because lampreys
have a vulnerable life-history stage (ammocoete)
that occupies a restricted habitat (burrows in soft
sediment in streams) which limits their ability to
escape a toxin. Consequently, population reduction
via toxicant application is logistically feasible
and effective. However, because of the unusual
characteristics of lampreys this success must be
viewed as a special rather than a general case for
predator control strategies. The Northern Pikeminnow (Ptychocheilus oregonensis)
Sport-Reward Program began in 1991 and is
sponsored by Bonneville Power Administration. SAN FRANCISCO ESTUARY & WATERSHED SCIENCE The program seeks to maintain a 10% to 20%
exploitation rate on Northern Pikeminnow
throughout the Columbia River by paying anglers
$4 to $8 to harvest fish > 228 mm TL (Porter 2010). The program removed over 2.2 million fish during
1998–2009 and is believed to have reduced predation
on juvenile salmonids; nonetheless, concomitant
increases in salmonid population abundance have
been difficult to detect (Carey et al. 2012). The lack
of positive population-level responses may be a result
of compensatory responses by other predators such
as Caspian terns (Hydroprogne caspia) and marine
mammals such as California sea lions (Zalophus
californianus, Carey et al. 2012). The possibility of
compensatory responses by other predators illustrates
a major shortcoming of predator control strategies;
rarely is predation mortality a function of just one
species. Although these programs are expensive—$14
million was paid out in bounties from 1998–2009
alone—angler reward systems may be more cost-
effective than if agencies performed removals
themselves (Carey et al. 2012). The context dependency of predator–prey interactions
combined with the high environmental, temporal,
and spatial variability of the Delta environment
undoubtedly will make quantifying the population-
level effects of predation on fish populations very
difficult. The Context-Dependency of Predation Using the previous
example, if we quantified the numerical response for
Striped Bass and Chinook Salmon smolts, we would
determine how changes in smolt abundance affected
the numerical abundance of Striped Bass. When
per-capita predator feeding rates are affected by
predator abundance (e.g., numerical response, intra-
or inter-specific interference competition) or when
only a fraction of prey are vulnerable to predators,
then predation rates may be relatively insensitive
to fluctuations in predator abundance (DeAngelis
et al. 1975; Ahrens et al. 2012). For example, the
abundance of Atlantic Cod (Gadus morhua) in the
Baltic Sea is not strongly related to changes in
their major prey juvenile herring (Clupea harengus,
Essington and Hansson 2004) and vice versa. In
addition, meaningful quantification of the functional
and numerical responses for abundant predators
on Central Valley Chinook Salmon populations
is complicated by the fact that the energetic
contribution of this prey to Delta predators is so low
that predator abundance is more likely influenced by
the abundances of alternate prey than by Chinook
Salmon abundance. 1. the junction of the Sacramento River and
Sutter Slough, 2. Georgiana Slough, 3. Delta Cross Channel Canal, 4. Franks Tract, 5. Mildred Island, 6. Stockton Ship Channel, 7. Clifton Court Forebay, 8. Borden Highway Bridge, 9. head of Old River, 10. head of Old River Barrier (HORB), 10. head of Old River Barrier (HORB), 11. Old River near Tracy, 11. Old River near Tracy, 11. Old River near Tracy, 12. pumping plant salvage release sites, and 13. the Red Bluff Diversion Dam. 13. the Red Bluff Diversion Dam. In addition, a recent study (Sabal et al. 2016),
demonstrated that the Woodbridge Irrigation In addition, a recent study (Sabal et al. 2016),
demonstrated that the Woodbridge Irrigation http://dx.doi.org/10.15447/sfews.2015v14iss2art8 7 Predator Control Case Studies I will review the history of predator control studies
because substantial concerns have been raised that
predation by both native and invasive predators has
contributed to declines in salmonid populations in
the Sacramento–San Joaquin Delta (CDFW 2011;
Grossman et al. 2013). This has led some members
of the public to call for control measures on some
predatory fishes, such as Striped Bass (Grossman et
al. 2013, www.youtube.com/watch?v=eEB3dnDmsBc). I will review the history of predator control studies
because substantial concerns have been raised that
predation by both native and invasive predators has
contributed to declines in salmonid populations in
the Sacramento–San Joaquin Delta (CDFW 2011;
Grossman et al. 2013). This has led some members
of the public to call for control measures on some
predatory fishes, such as Striped Bass (Grossman et
al. 2013, www.youtube.com/watch?v=eEB3dnDmsBc). Control of invasive fishes is not an uncommon
fishery management strategy (Kolar et al. 2010) but
it has not had a high success rate. At present, several
large-scale predator removal programs are underway
in North America to aid in the recovery of native Control of invasive fishes is not an uncommon
fishery management strategy (Kolar et al. 2010) but
it has not had a high success rate. At present, several
large-scale predator removal programs are underway
in North America to aid in the recovery of native 8 JULY 2016 JULY 2016 Lake Trout have been widely introduced for sport
fishing in western US lakes and reservoirs. In some
systems, these fish threaten native and introduced
salmonid populations (Dux et al. 2011). Commercial
fishing and sport angling appear to have reduced
Lake Trout abundance and allowed for kokanee
recovery at Lake Pend Oreille, ID (Hansen et al. 2010). Angler incentives do not appear to have been
effective at Flathead Lake, Montana (Federal Register
2012). Although commercial-scale netting has
removed over 450,000 Lake Trout from Yellowstone
Lake (Wyoming/Montana), this species continues to
threaten native Cutthroat Trout (Syslo et al. 2011). removal (Beamesderfer 2000), which is expensive. In addition, because of the generalist nature of most
fish predators, a decrease in the abundance of one
predator may result in increases in the abundance
of competing predators, or in the abundance of
competitors of the prey species; the result being a
net overall negative effect on the prey population
of interest. Predator Control Case Studies Given the dynamic and highly modified
environment of the Delta, if the goal is increasing
population sizes of species of concern, such as
Chinook Salmon or Delta Smelt, it will take careful
study before any predator removal or suppression
technique should be undertaken. As part of the Upper Colorado River Endangered
Fish Recovery Plan (USFWS 2012), invasive Channel
Catfish (Ictalurus punctatus), Northern Pike (Esox
lucius), Smallmouth Bass (Micripterus dolomieu)
and other potential predators are being removed
from critical habitat for ESA listed cyprinids and
catostomids (Tyus and Sauders 2000; Johnson et al. 2008). Invasive fish control in the Upper Colorado
River Basin costs over $1 million annually (Mueller
2005). Demonstrating native fish responses to
removal of invasive fishes has been complicated
by highly variable environmental conditions that
differentially affect predators and prey. However, the
available literature demonstrates that even in isolated
reaches with intense removal efforts, there have been
few demonstrable positive responses from native
fishes (Bestgen et al. 2007; Skorupski et al. 2012). PREDATION ON DELTA FISHES The assemblage of predatory fishes in the Delta is
dominated by invasive species (Table 1) (Brown
and Michniuk 2007; Nobriga and Feyrer 2007;
NRC 2010; Cavallo et al. 2012; NRC 2012; Brown
2013, unreferenced, see “Notes"), although most
non-piscine predators are native species. General
survey data provide some estimates of abundance
or relative abundance (catch-per-unit-effort) data
for some predators and prey fishes at certain times
and locations; however, quantitative abundance
estimates for many predators and prey frequently are
lacking. Nonetheless, numerous predators such as
Striped Bass, Largemouth Bass, ictalurids, Mississippi
Silversides, some centrarchids, and birds (e.g., ducks,
herons, egrets, and terns) appear to be common in
the Delta (Nobriga et al. 2002; Dege and Brown 2004;
Brown and May 2006; CDFW 2013). The literature on predator removal as a management
strategy for recovery of desirable species indicates
there is little evidence for strong, positive,
l ti
l
l
i Predation Studies on Delta Fishes Nonetheless,
all studies possess shortcomings, and in the absence
of complete data these models serve as a starting
point for management decisions and as hypothesis-
generating tools for further studies. Very recent published work by Sabal et al. (2016)
and Demetras et al. (2016) indicate that Striped
Bass predation upon juvenile Chinook Salmon could
be substantial, although the amount of predation
experienced by wild as opposed to hatchery fish—or
those in habitats other than predation hot spots—
remains unknown. In a multi-faceted study, Sabal et
al. (2016) demonstrated that Striped Bass aggregated
below the Woodbridge Irrigation District Dam on
the Mokelumne River (a predation hot spot) and that
Chinook Salmon survivorship increased when Striped
Bass were removed. The Woodbridge Dam has a
fish ladder, but Striped Bass do not typically ascend
fish ladders; rather ,they typically aggregate below
dams and fish ladders where they prey extensively
on smaller fishes (Davis et al. 2012). In predation
hot spots in the Delta, predators may aggregate and
consume large numbers of prey that are disoriented
by: (1) unnatural or reversed flow patterns, and
(2) modified habitat structures such as fish ladders,
water abstraction devices, modified channels, or
impoundments (Davis et al. 2012; Grossman et al. 2013). Demetras et al. (2016) developed an innovative
predator detection system that documented predation
by Striped Bass and unidentified fish predators on
tethered Chinook Salmon, and found a positive
relationship between current velocity and predation
rate and an inverse relationship between water
column depth and predation rate. Although this
highly innovative system documented predation by
Striped Bass and other predators on tethered Chinook
Salmon, it is difficult to extrapolate these results to
estimates of predation rates throughout the Delta. Several recent studies address the predation issue
directly, most notably Cavallo et al. (2012), Sabal
et al. (2016) and Demetras et al. (2016). In an
ambitious study, Cavallo et al. (2012), attempted a
BACI (Before, After, Control, Intervention) assessment
of how predatory fishes affected Chinook salmon
juvenile survival, using boat electrofishing to remove
predatory fishes from a section of the Mokelumne
River. As might be expected with field experiments,
the predator removal experiment was relatively
short-term (slightly over 2 weeks long). Nonetheless,
Chinook Salmon displayed higher survivorship in
the removal section than in the unshocked control
section after the first predator removal; however,
the second removal did not result in increased
Chinook Salmon survivorship. Predation Studies on Delta Fishes Predator removal, even in relatively simple systems
such as reservoirs and lakes, is a difficult and costly
management technique, and the lack of success
illustrates the challenges inherent in functionally
eliminating wild fish populations in systems
with complex dynamics. Eradication generally is
unlikely, except in small, isolated systems where
re-invasion can be prevented (Kolar et al. 2010),
and even in these systems re-introductions may
occur via disgruntled members of the public. A variety of approaches have been used to elucidate
relationships among Delta predators and prey. The
vast majority of studies are dietary investigations
whose main purpose was to quantify the diets of
game fishes (e.g., Thomas 1967; Stevens 1966;
Bryant and Arnold 2007; Nobriga and Feyrer 2007),
although several more recent studies directly address
consumption of prey by predatory fishes (Lindley
and Mohr 2003; Cavallo et al. 2012; Loboschefsky
et al. 2012; FISHBIO 2013; Nobriga et al. 2013). The
landmark dietary studies in Turner and Kelly (1966)
provide important information for both game and
several non-game species. Nonetheless, the design of Predator suppression may sometimes facilitate
increases in abundances of prey fish populations,
but this requires intensive and sustained efforts at http://dx.doi.org/10.15447/sfews.2015v14iss2art8 9 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 Pikeminnow removal program was put into practice,
given that both Caspian tern and sea lion predation
apparently increased concomitantly with the removal
program (Carey et al. 2012). Nonetheless, the finding
of increased Chinook Salmon survivorship in the first
removal of Cavallo et al. (2012) may be conservative,
because fishes in the control section were not
shocked and, therefore, likely in better condition. most dietary studies limits their use for quantifying
how predators affect prey fish populations (see
below). A majority of the strongest studies (Lindley
and Mohr 2003; Loboschefsky et al. 2012; Nobriga
et al. 2013) involve mathematical modeling that
uses empirical data, which provide insights into the
potential dynamics of Striped Bass predation on Delta
fishes. However, the modeling studies still possesses
shortcomings that limit their ability to predict future
dynamics including: (1) lack of independent empirical
verification of the dynamics modeled and predicted
outcomes, (2) lack of empirical verification of model
assumptions, and (3) limited empirical databases
(e.g., limited temporal and spatial data as well as a
lack of resolution in some data; e.g., prey categories
such as “fish” rather than prey species). Predation Studies on Delta Fishes Unfortunately,
predator densities in the treatment section tripled
after the first removal, which underscores the
importance of potential compensatory responses
by other predatory species when a single predator
species is removed. This phenomenon is the biggest
weakness of the “predator removal” management
approach (e.g., Striped Bass predation limits Chinook
Salmon populations), because in the Delta there
are literally 10 to 20 other predatory species that
could potentially increase in abundance (and prey
consumption) if a dominant predator is removed. Indeed, this may have occurred when the Northern Much of the data for my analysis came via the
courtesy of researchers who provided data from
their unpublished studies (e.g., Barry 2015; Brandl
et al. 2015; Smith et al. 2015; Young 2015; Zeug
2015, all unreferenced, see “Notes"); and these data
and the work of Baerwald et al. (2013) illustrate the
advantages of DNA analysis for dietary analyses. Indeed, this may have occurred when the Northern 10 JULY 2016 JULY 2016 My analysis yielded few generalizations regarding
predator–prey interactions for Delta fishes other
than the observation that most predators were
unspecialized and consumed a wide variety of both
native and invasive fishes. The sole exception was
Prickly Sculpin which, when it consumed fish, preyed
upon mostly natives (Table 2; Merz 2002b). Both
Striped and Largemouth Bass exhibited broad dietary
breadths, with Striped and Largemouth Bass preying
upon 32 and 28 categories of prey, respectively
(Table 2). These predators preyed upon a wide variety
of both native and invasive fishes, and, as important
game fish, had the broadest temporal and spatial
coverage in dietary data (Table 2). The Sacramento
Pikeminnow, a native predator, also displayed
broad dietary breadth, with 14 different categories
of fish prey eaten. These data reinforce the general
opinion of the literature that most fish predators are
generalists that consume many different prey types
(Moyle and Cech 2004). Analyses using DNA typing allow investigators to
analyze large numbers of stomachs with a high level
of precision of prey identification. Unfortunately at
present, they cannot be used to quantify the intensity
of prey consumption, but only whether or not a
given prey species has been consumed. The Data and Analysis I searched the literature and contacted researchers
actively working on dietary or predator–prey studies
on Delta fishes and compiled a matrix of predator
species and their piscine prey. Sources are listed in
Table 2. Based on the frequency of prey occurrence
in predator gut contents, I ranked predator
consumption as occasional, moderate, or common
(Table 2). I used these data to evaluate the frequency
of predation on native and invasive species and their
hypothesized effect on prey populations (Table 3). I
also evaluated the data base of dietary and predation
papers and ranked data for each species as: none,
fair, good, or excellent (Table 2). In general, the data
base of dietary/predation studies is fair but very
weak for mammals, many carnivorous birds and
some reptiles and amphibians (Table 2). In addition,
the data base is biased towards highly valued game
species (e.g., Striped and Largemouth Bass) and
the level of prey resolution varies according to
the authors’ purposes (in many studies, broad prey
categories were used e.g., “fish”). I recorded 32
different predator categories, although categories
such as gulls, herons and egrets, and terrestrial garter
snakes contained multiple predatory species (Table 2). I recorded 36 different prey species and five multi-
species categories, including unidentified fishes,
unidentified salmonids, unidentified shad, Lepomis
species, and Tridentiger species. The data indicated
that most predators only were occasional consumers
of individual prey species, although moderate and
common consumption also were observed, for
example, Most predators fed primarily on invasive species,
which are the most abundant fishes in the Delta
(Brown and Michniuk 2007). Given the generalist
nature of vertebrate predators, this likely represents
consumption of prey in proportion to their
abundance. In addition, it is likely that some
predators, such as snakes, fed primarily on invasive
species because both predator and prey are found
in modified habitats where invasives dominate
(B. Halstead, pers. comm., to me, 2015, unreferenced,
see “Notes"). The effects of avian, reptilian,
amphibian, and mammalian predation on fishes
in the Delta are not well known, although Caspian
terns can consume high numbers of stocked Chinook
Salmon (Evans et al. 2011; Andrean et al. 2012;
Hostetter et al. 2015). Most predators fed primarily on invasive species,
which are the most abundant fishes in the Delta
(Brown and Michniuk 2007). Given the generalist
nature of vertebrate predators, this likely represents
consumption of prey in proportion to their
abundance. SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 Table 2 Predator–prey interactions among Delta animals. Prey consumption by predators is ranked as O–occasional <5% by frequency of
occurrence, M–moderate > 5% to 49%, C–Common > 50%. A question mark indicates that the predator is known to be piscivorous but no
dietary data are available for the Delta. Table 2 Predator–prey interactions among Delta animals. Prey consumption by predators is ranked as O–occasional <5% by frequency of
occurrence, M–moderate > 5% to 49%, C–Common > 50%. A question mark indicates that the predator is known to be piscivorous but no
dietary data are available for the Delta. 12
occurrence, M–moderate > 5% to 49%, C–Common > 50%. A question mark indicates that the predator is known to be piscivorous but no
dietary data are available for the Delta. PREDATOR
Sacramento Pikeminnow
Sacramento Perch
Sacramento Splittail
Steelhead
Chinook Salmon
Prickly Sculpin
Striped Bass
Largemouth Bass
Smallmouth Bass
Warmouth
Bluegill
White Crappie
Black Crappie
White Catfish
Channel Catfish
Brown Bullheads
Black Bullheads
Mississippi Silversides
Common carp
Yellowfin goby
Shimofuri goby
Caspian Tern
California Least Tern
Double-crested cormorants
Herons & Egrets
Gulls
Giant Gartersnake
Aquatic Gartersnake
Common Garteresnake et al. Bullfrogs
Western Pond Turtles
Data quality
G
F
F
F
F
F
E
G
F
F
F
F
F
F
F
F
F
F
F
F
F
N
N
N
F
N
N
N
F
PREY
Native
Bay Pipefish
O33
Chinook Salmon
O1, 4,2 5
O-C22
M2, 8 C7
O1, 23, 25
M8
C-M
O23
O25
M2, 25
O6 O-?24
Delta Smelt
O2,4
O-C19
O-M22
O23
O2
M-C9
?11
Hitch
O4
O13
Longfin Smelt
C-M
O2
Pacific Lamprey
O21
O4, 33
O-M22
O13
Prickly Sculpin
O1
O21 O-M21,32
O1,33
M1
O13
O-M32
O3, a
O-M32
Sacramento
Blackfish
O4
O13
Sacramento
Pikeminnow
M2
C-M
M2
M2
Sacramento
Sucker
O21
O-M21
Splittail
O2
O1
M2, 25
O-M22
O1
M2
M2
M2,25
Steelhead
O2,25
M25
O6
Threespine
Stickleback b
O4
O13
O-M3, a
Tule Perch
O1
O1 ,33
O1, 13
White Sturgeon
O2 ,25
Unidentified
salmonids
M-C10
C10
O-?31
Cottidae
O33
Unidentified
fishes c
M1
M-C10 O-C14 M15 O-C18 O21
O21
M1, 4, 8,15, 22, 33
M-C20, 33
C10
M1, 8, 3, 23
M8
O23 O23
M23
O5
M15
M5,25
O5
M5
O15
O-?24 O-? O-?31 O-? O-?26 O-?26, 28 ?26, 28 ?28, 29, 30 O-?27
a. 40% by volume. b. Suisun Bay. c. Includes invasive fishes. The Data and Analysis In addition, it is likely that some
predators, such as snakes, fed primarily on invasive
species because both predator and prey are found
in modified habitats where invasives dominate
(B. Halstead, pers. comm., to me, 2015, unreferenced,
see “Notes"). The effects of avian, reptilian,
h b
d
l
d
f h amphibian, and mammalian predation on fishes
in the Delta are not well known, although Caspian
terns can consume high numbers of stocked Chinook
Salmon (Evans et al. 2011; Andrean et al. 2012;
Hostetter et al. 2015). Several additional impediments limited my ability
to reach strong conclusions about the effects of
predators on the abundance of prey species. First,
dietary data lacked resolution to the family or species
level because predation on fish prey frequently was
listed merely as “unidentified fishes.” Second, there
was a lack of data on direct predation as well as a
lack of dietary data that included prey availability
so that prey selection could be determined (also see
Grossman et al. 2013). Third, although we know
fish were consumed, we do not know if they were
healthy, stressed, or even dead. 1. Moderate: Sacramento Pikeminnow consuming
Longfin Smelt, Striped Bass consuming
Sacramento Splittail, Largemouth Bass
consuming Prickly Sculpin; and 2. Common: Striped Bass consuming Chinook
Salmon, Largemouth Bass consuming
Sacramento Pikeminnow, Channel Catfish
consuming Largemouth Bass (see also Table 2). 11 http://dx.doi.org/10.15447/sfews.2015v14iss2art8 ERRATA: REVISED PAGE 12 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE Sources: 1Nobriga and Feyrer 2007, 2Brandl et al. 2015*, 3O’Rear 2007, 4Stevens 1966, 5Turner 1966a, 6Andrean et al. 2012, 7Lindley and Mohr 2003,
8FISHBIO 2013, 9Baerwald et al. 2013, 10Tucker et al. 1998, 11Bennett 2005, 12Bennett 1993, 13Conrad et al. 2013*, 14Crain and Moyle 2011, 15Whitley
and Bollens 2014, 16Matern and Brown 2005, 17Clark et al. 2009, 18Merz 2002a, 19Nobriga et al. 2013, 20Feyrer et al 2003, 21Merz 2002b, 22Thomas
1967 (includes data for the entire San Francisco Bay system, only Delta prey were recorded), 23Turner 1966b, 24Riensche et al. 2012, 25Smith et al. 2015*, 26Halstead et al. 2015*, 27Bury 1986, 28Barry 2015*, 29Wylie et al. 2003, 30Corse and Metter 1980, 31Kushlan and Hancock 2005, 32Young 2015*,
Zeug et al. 2015*. An asterisk indicates the data are unpublished. Sources: 1Nobriga and Feyrer 2007, 2Brandl et al. 2015*, 3O’Rear 2007, 4Stevens 1966, 5Turner 1966a, 6Andrean et al. 2012, 7Lindley and Mohr 2003,
8FISHBIO 2013, 9Baerwald et al. 2013, 10Tucker et al. 1998, 11Bennett 2005, 12Bennett 1993, 13Conrad et al. 2013*, 14Crain and Moyle 2011, 15Whitley
and Bollens 2014, 16Matern and Brown 2005, 17Clark et al. 2009, 18Merz 2002a, 19Nobriga et al. 2013, 20Feyrer et al 2003, 21Merz 2002b, 22Thomas
1967 (includes data for the entire San Francisco Bay system, only Delta prey were recorded), 23Turner 1966b, 24Riensche et al. 2012, 25Smith et al. 2015*, 26Halstead et al. 2015*, 27Bury 1986, 28Barry 2015*, 29Wylie et al. 2003, 30Corse and Metter 1980, 31Kushlan and Hancock 2005, 32Young 2015*,
Zeug et al. 2015*. An asterisk indicates the data are unpublished. Sources: 1Nobriga and Feyrer 2007, 2Brandl et al. 2015*, 3O’Rear 2007, 4Stevens 1966, 5Turner 1966a, 6Andrean et al. 2012, 7Lindley and Mohr 2003,
8FISHBIO 2013, 9Baerwald et al. 2013, 10Tucker et al. 1998, 11Bennett 2005, 12Bennett 1993, 13Conrad et al. 2013*, 14Crain and Moyle 2011, 15Whitley
and Bollens 2014, 16Matern and Brown 2005, 17Clark et al. 2009, 18Merz 2002a, 19Nobriga et al. 2013, 20Feyrer et al 2003, 21Merz 2002b, 22Thomas
1967 (includes data for the entire San Francisco Bay system, only Delta prey were recorded), 23Turner 1966b, 24Riensche et al. 2012, 25Smith et al. 2015*, 26Halstead et al. 2015*, 27Bury 1986, 28Barry 2015*, 29Wylie et al. 2003, 30Corse and Metter 1980, 31Kushlan and Hancock 2005, 32Young 2015*,
Zeug et al. 2015*. An asterisk indicates the data are unpublished. 12 REVISED NOVEMBER 2016 Table 2 (Continued ) Predator-prey interactions among Delta animals. Prey consumption by predators is ranked as O–occasional <5% by
frequency of occurrence, M–moderate > 5% to 49%, C–Common >50%. A question mark indicates that the predator is known to be piscivorous
but no dietary data are available for the Delta. Table 2 (Continued ) Predator-prey interactions among Delta animals. Prey consumption by predators is ranked as O–occasional <5% by
frequency of occurrence, M–moderate > 5% to 49%, C–Common >50%. A question mark indicates that the predator is known to be piscivorous
but no dietary data are available for the Delta. but no dietary data are available for the Delta. PREDATOR
Sacramento Pikeminnow
Sacramento Perch
Sacramento Splittail
Steelhead
Chinook Salmon
Prickly Sculpin
Striped Bass
Largemouth Bass
Smallmouth Bass
Warmouth
Bluegill
White Crappie
Black Crappie
White Catfish
Channel Catfish
Brown Bullheads
Black Bullheads
Mississippi Silversides
Common carp
Yellowfin goby
Shimofuri goby
Caspian Tern
California Least Tern
Double-crested cormorants
Herons & Egrets
Gulls
Giant Gartersnake
Aquatic Gartersnake
Common Garteresnake et al. Bullfrogs
Western Pond Turtles
Data quality
G
F
F
F
F
F
E
G
F
F
F
F
F
F
F
F
F
F
F
F
F
N
N
N
F
N
N
N
F
INVASIVE
American Shad
O1, 33
O1, 4
O-M22
O23
Bigscale Logperch
O1
O1
O1
O13
?5
O-M32
Black Bullhead
O-?26
Black Crappie
O4
O13
M23
Bluegill
O4
O13
M23
O23
?5
O-?26
Clupeidae
O33
Common Carp
O4
O-M22
O13
O-?26
Fathead Minnow
O-?26
Gobiidae
O33
Golden Shiner
O1
O4
O1,13
O-M32
O-?26
Hypomesus spp. O33
Green Sunfish
M22
O-?26
Largemouth Bass
O25
O1,2
M25
O1,13
M2
C25
M2
C25
O-?26
Lepomis spp. ?21
M1
O13
O-?26
Mississippi
Silverside
M-O
O33
M2
O13
O-M32
M1
M2
O32
M2
M2
O32
O-?26
Rainwater Killifish
O1,13
Red Shiner
O-?26
Redear Sunfish
O13
Smallmouth Bass
M-O
O2
C-M
M2
M2
Striped Bass
O1
C2
O1, 22
M4
O1, 13
C2
C2
M32
M23
M-O
M2
C25
?12
Threadfin Shad
M-O
O25, 33
O-M32
M1, 2, 4
O1, 13
O-M32
M2,23
O-M23
?5
O25
M2
O25
M2
Tridentiger spp. O1
O1,33
O1, 13
O3, a
Unidentified Shad
M1
M1
M1
O-M16
Yellowfin Goby
O33
M1
O33
M1
M1
O13
Wakasagi
O2, 33
White Catfish
O-M23
O-?26, 29
Western
Mosquitofish
O1
O-M32
O1, 13
O-?28
Warmouth
O13 but no dietary data are available for the Delta. SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 Table 3 Hypothesized effects of predators on Delta fish populations based on Table 2. If a citation is not given, the entry is based on the
author’s personal observation. A “U” in a category means that only unidentified fishes were listed as fish prey. Scientific names listed only
when not previously mentioned. Table 3 Hypothesized effects of predators on Delta fish populations based on Table 2. If a citation is not given, the entry is based on the
author’s personal observation. A “U” in a category means that only unidentified fishes were listed as fish prey. Scientific names listed only
when not previously mentioned. when not previously mentioned. Species
Abundance
(since 1980)
% Native fish in diet
(frequency of
occurrence)
% Invasive fish in diet
(frequency of
occurrence)
Hypothesized predator effect
on prey population
Native predators
Sacramento Pikeminnow
Likely decreasing a
30
70
Unlikely, except in predation hot spots
Thicktail Chub, Gila crassicauda
Extinct
None
None
None
Sacramento Perch
Functionally extinct
None
None
none
Sacramento Splittail
Common
U
U
Unlikely
Steelhead
Declining
U
U
Unlikely
Chinook Salmon
Declining
100
0
Unlikely
Prickly Sculpin
Common
75
25
Unlikely, low % of fish in diet
Caspian tern
Common b
100 c
Unknown
Possibly on stocked salmonids
River otter
Increasing d
Piscivorous
Piscivorous
Possibly in isolated habitats or hot spots
Giant garter snake, Thamnophis gigas
Threatened
Largely piscivorous
Largely piscivorous
Unlikely to be significant
Herons and egrets,
Ardea and Nycticorax spp. Common
Largely piscivorous
Largely piscivorous
Unlikely to be significant
Mergansers, Mergus spp. Uncommon
U
U
Possibly in isolated habitats or hot spots
Double-crested cormorant
Phalacrocorax auritus
Common and increasing e
Largely piscivorous
Largely piscivorous
Possibly in isolated habitats or hot spots
Western grebe
Aechmophorus occidentalis
Common
Largely piscivorous
Largely piscivorous
Possibly in isolated habitats or hot spots
Western pond turtles
Actinemys marmorata
Common
U
U
? California least tern
Sternulla antillarum browni
Increasing
100
0
? Gulls
? U
U
? Aquatic garter snake
Thamnophis atratus
? U
U
? Commom garter snake
Thamnophis sirtalis
? 0
100
? Invasive predators
Largemouth Bass
Increasingf
33
67
Possibly
Striped Bass
(¯ age-0 in pelagic surveys, or
stable for sub-adults, ¯ for adults)g
47
53
Possibly
Smallmouth Bass
? 6
33
? Mississippi Silverside
Abundant
50
50
Possibly for eggs, larvae, juveniles
White Catfish
Common
40
60
? Channel Catfish
Common
50
50
? REVISED NOVEMBER 2016 PREDATOR
Sacramento Pikeminnow
Sacramento Perch
Sacramento Splittail
Steelhead
Chinook Salmon
Prickly Sculpin
Striped Bass
Largemouth Bass
Smallmouth Bass
Warmouth
Bluegill
White Crappie
Black Crappie
White Catfish
Channel Catfish
Brown Bullheads
Black Bullheads
Mississippi Silversides
Common carp
Yellowfin goby
Shimofuri goby
Caspian Tern
California Least Tern
Double-crested cormorants
Herons & Egrets
Gulls
Giant Gartersnake
Aquatic Gartersnake
Common Garteresnake et al. Bullfrogs
Western Pond Turtles
Data quality
G
F
F
F
F
F
E
G
F
F
F
F
F
F
F
F
F
F
F
F
F
N
N
N
F
N
N
N
F
INVASIVE
American Shad
O1, 33
O1, 4
O-M22
O23
Bigscale Logperch
O1
O1
O1
O13
?5
O-M32
Black Bullhead
O-?26
Black Crappie
O4
O13
M23
Bluegill
O4
O13
M23
O23
?5
O-?26
Clupeidae
O33
Common Carp
O4
O-M22
O13
O-?26
Fathead Minnow
O-?26
Gobiidae
O33
Golden Shiner
O1
O4
O1,13
O-M32
O-?26
Hypomesus spp. O33
Green Sunfish
M22
O-?26
Largemouth Bass
O25
O1,2
M25
O1,13
M2
C25
M2
C25
O-?26
Lepomis spp. ?21
M1
O13
O-?26
Mississippi
Silverside
M-O
O33
M2
O13
O-M32
M1
M2
O32
M2
M2
O32
O-?26
Rainwater Killifish
O1,13
Red Shiner
O-?26
Redear Sunfish
O13
Smallmouth Bass
M-O
O2
C-M
M2
M2
Striped Bass
O1
C2
O1, 22
M4
O1, 13
C2
C2
M32
M23
M-O
M2
C25
?12
Threadfin Shad
M-O
O25, 33
O-M32
M1, 2, 4
O1, 13
O-M32
M2,23
O-M23
?5
O25
M2
O25
M2
Tridentiger spp. O1
O1,33
O1, 13
O3, a
Unidentified Shad
M1
M1
M1
O-M16
Yellowfin Goby
O33
M1
O33
M1
M1
O13
Wakasagi
O2, 33
White Catfish
O-M23
O-?26, 29
Western
Mosquitofish
O1
O-M32
O1, 13
O-?28
Warmouth
O13 13 http://dx.doi.org/10.15447/sfews.2015v14iss2art8 http://dx.doi.org/10.15447/sfews.2015v14iss2art8 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE SAN FRANCISCO ESTUARY & WATERSHED SCIENCE Warmouth
Common h
0
100
? Black crappie
Common h
40
60
? Bluegill
Common
U
U
? Brown bullheads
Common
U
U
? Black Bullheads
Common
U
U
? Common Carp
Common
U
U
? Shimofuri Goby
Common
0
100
? Bullfrog Lithobates catesbiana
Common
Piscivorous
Piscivorous
Possibly in isolated habitats or hot spots
a. FISHBIO 2013; Nobriga and Feyrer 2007. b. Evans et al. 2011; Andrean et al 2012. c. Only dietary data from recovered tags of stocked salmonids. d. P. Moyle, pers. comm., 2015, unreferenced, see “Notes.”
e. Adkins et al. 2014. f. Salvage data from the State Water Project and Central Valley Project in the Sacramento-San Joaquin
Delta (http://www.delta.dfg.ca.gov/Data/Salvage/), Brown and Michniuk 2007; Nobriga and Feyrer
2007; Cavallo et al. 2012; Conrad 2013, unreferenced, see “Notes"; FISHBIO 2013. g. Nobriga and Feyrer 2007; Cavallo et al. 2012; CDFW 2013; Grossman et al. 2013; FISHBIO 2013. h. Turner and Kelly 1966. f. Salvage data from the State Water Project and Central Valley Project in the Sacramento-San Joaquin
Delta (http://www.delta.dfg.ca.gov/Data/Salvage/), Brown and Michniuk 2007; Nobriga and Feyrer
2007; Cavallo et al. 2012; Conrad 2013, unreferenced, see “Notes"; FISHBIO 2013. g. Nobriga and Feyrer 2007; Cavallo et al. 2012; CDFW 2013; Grossman et al. 2013; FISHBIO 2013. h. Turner and Kelly 1966. 14 JULY 2016 JULY 2016 The high numbers of Chinook Salmon and the
occasional Steelhead eaten by Channel Catfish
suggest that these prey may have been stressed or
dead when consumed, especially because genetic
analysis rather than visual inspection determined
their frequency of consumption (Smith et al. 2015). Fourth, my conclusions were limited by the fact that
frequency-of-occurrence data are not necessarily
correlated with predation intensity. For example, a
frequency of occurrence of 100% is obtained when
each individual of a predatory species consumes just
one individual of a given prey species. However, the
same value is obtained if each predator consumes
25 individuals of a given species. Consequently,
Tables 2 and 3 are rudimentary estimates of
predator–prey interactions for Delta fishes. Fifth,
many of the dietary studies were limited in their
spatial and temporal coverage, which may result in
over-estimation of the intensity of predator–prey
interactions if data were collected during a period
when the predator fed intensively on a prey that
only was temporarily abundant. SAN FRANCISCO ESTUARY & WATERSHED SCIENCE Not surprisingly,
there is a trade-off between logistical ease and
realism, with indirect approaches such as population
or bioenergetic modeling producing results that may
be consistent with predator limitation, but typically
cannot exclude alternative agents of mortality. Hence, their conclusions must be considered
correlative rather than causal. Conversely, predator
removal experiments are logistically difficult and
may have limited realism (e.g. exclusions of pelagic
roving predators), but may directly address whether
predators depress prey populations on a local scale
(Cavallo et al. 2012; Grossman et al. 2013). It will
take a combination of methods that focus on direct
experimentation, population modeling, and dietary
and behavioral studies to yield further insights into
the effects of predation on Delta fishes. Given the
difficulty of separating ultimate from proximate
causes of mortality, and the widespread distribution
of bioactive contaminants on fishes throughout the
Delta (Fong et al., submitted), it will be very difficult
to untangle the ultimate from proximate causes of
predation mortality for prey fish populations. SAN FRANCISCO ESTUARY & WATERSHED SCIENCE Conversely, the data
may under-estimate these relationships if samples
were lacking for multiple days within a season, or
seasons within a single year, or multiple years. Sixth,
it is well known that even non-predatory fishes
will consume both fish eggs and larvae, yet these
resources typically are only available for weeks or a
month, and are frequently missed in dietary studies. It is possible that some species such as Mississippi
Silversides may prey significantly on eggs or larvae
of species such as Delta Smelt (Baerwald et al. 2012). Finally, recent DNA analyses of stomach contents
of Delta fish predators may allow a species’ diet
to be quantified accurately and quickly (Baerwald
et al. 2012; Brandl et al. 2015, unreferenced, see
“Notes"; Smith et al. 2015), but cannot quantify the
energetic importance of a given prey to the predator,
and, concomitantly, the number of prey eaten by an
individual predator. Although it is beyond the scope of this study, (2013, unreferenced, see “Notes”) provide useful
examples of modeling approaches to predator–prey
dynamics, Loboschefsky et al. (2013) of bioenergetic
modeling, and Cavallo et al. (2012) and Ferrari et al. (2014) of direct experimentation. Not surprisingly,
there is a trade-off between logistical ease and
realism, with indirect approaches such as population
or bioenergetic modeling producing results that may
be consistent with predator limitation, but typically
cannot exclude alternative agents of mortality. Hence, their conclusions must be considered
correlative rather than causal. Conversely, predator
removal experiments are logistically difficult and
may have limited realism (e.g. exclusions of pelagic
roving predators), but may directly address whether
predators depress prey populations on a local scale
(Cavallo et al. 2012; Grossman et al. 2013). It will
take a combination of methods that focus on direct
experimentation, population modeling, and dietary
and behavioral studies to yield further insights into
the effects of predation on Delta fishes. Given the
difficulty of separating ultimate from proximate
causes of mortality, and the widespread distribution
of bioactive contaminants on fishes throughout the
Delta (Fong et al., submitted), it will be very difficult
to untangle the ultimate from proximate causes of
predation mortality for prey fish populations. (2013, unreferenced, see “Notes”) provide useful
examples of modeling approaches to predator–prey
dynamics, Loboschefsky et al. (2013) of bioenergetic
modeling, and Cavallo et al. (2012) and Ferrari et al. (2014) of direct experimentation. ACKNOWLEDGEMENTS is not strong, and I would urge future efforts to
undertake long-term dietary studies combined ,with
attempts to establish predator preferences, rather
than just consumption. This will be particularly
important given the highly fluctuating environmental
conditions typical of the Delta and the likely
changes that global climate change will produce,
including: (1) increases in sea-level; (2) shifts in
the variability, timing, and amount of precipitation;
and (3) increased temperatures, which may facilitate
future species invasions (Moyle et al. 2013; Dettinger
et al., submitted). If the Delta experiences more
drought and increased water exports, fishes may be
concentrated in small patches of suitable habitat,
which could alter predator–prey relationships and
render prey species more susceptible to predation
not only by fishes but also by birds, reptiles, and
mammals. Although the data base is not extensive,
it is clear that predation on fishes in the Delta
is a common phenomenon that warrants further
investigation. Hopefully future investigations will
elucidate the effects of this phenomenon on both
native and invasive fishes in the Delta. is not strong, and I would urge future efforts to
undertake long-term dietary studies combined ,with
attempts to establish predator preferences, rather
than just consumption. This will be particularly
important given the highly fluctuating environmental
conditions typical of the Delta and the likely
changes that global climate change will produce,
including: (1) increases in sea-level; (2) shifts in
the variability, timing, and amount of precipitation;
and (3) increased temperatures, which may facilitate
future species invasions (Moyle et al. 2013; Dettinger
et al., submitted). If the Delta experiences more
drought and increased water exports, fishes may be
concentrated in small patches of suitable habitat,
which could alter predator–prey relationships and
render prey species more susceptible to predation
not only by fishes but also by birds, reptiles, and
mammals. Although the data base is not extensive,
it is clear that predation on fishes in the Delta
is a common phenomenon that warrants further
investigation. Hopefully future investigations will
elucidate the effects of this phenomenon on both
native and invasive fishes in the Delta. I would like to acknowledge my co-authors of
the 2013 Fish Predation on Salmonids Report,
T. Essington, B. Johnson, J. Miller, N. Monson,
and T. Pearsons, who aided in the development
of several concepts described in this paper. ACKNOWLEDGEMENTS I am
also deeply grateful for the willingness of the
following scientists to provide unpublished data
and information on potential Delta predators:
S. Barry, S. Brandl, R. Connon, L. Conrad, C. Elphick,
B. Halstead, S. Hayes, J. Kelly, S. Lindley, B. May,
G. Nafis, P. Moyle, T. O'Rear, R. Perry, D. Roby,
J. Smith, D. Shuford, S. Zeug, and the UC Davis
Genomic Variation laboratory. The manuscript
was improved by the comments of B. Bozeman,
S. Brandl, L. Conrad, J. Cullen, S. Hayes, P. Moyle,
J. Neuswanger, and T. Simon. The stimulation of
Jittery Joe’s, Two Story, and Michter’s Single Barrel
aided in the development and refinement of the ideas
in the ms. Finally, I appreciate the support of the
Warnell School of Forestry and Natural Resources,
University of Georgia, and the Delta Stewardship
Council who provided the opportunity to write this
paper. So many individuals aided in the production
of this paper that I apologize in advance for
anyone I may have inadvertently omitted from the
Acknowledgements. Finally, it has recently been proposed that Striped
Bass populations be significantly reduced to
facilitate recovery of endangered Central Valley
Chinook Salmon (http://www.youtube.com/
watch?v=eEB3dnDmsBc). Although from a scientific
standpoint it is always interesting to see how
removal of an abundant species affects community
structure and ecosystem processes, unless a removal
study is conducted under rigorous experimental
conditions (controls, monitoring of other predators,
demonstration of direct predation and predator
per-capita effects), it is unlikely to yield conclusive
information on the relationship between predation
and Chinook Salmon survival. As mentioned
previously, the most likely outcome of Striped Bass
removal is that a competing predator will increase
in abundance and there will be little reduction in
predation mortality for Chinook Salmon. It is likely
that the most productive management strategy for
decreasing predation on Chinook Salmon and other
Delta fishes is to restore natural habitat and flows,
especially in predation hot spots. CONCLUSIONS An understanding of any important ecological system
requires extensive study of the abiotic and biotic
relationships driving the system. The Sacramento–San
Joaquin Delta supports a biological stew of native
and invasive predators and prey whose ingredients
are likely to change over time as new invasions
occur and climate change progresses (Dettinger et al.,
submitted; Wiens et al., this volume). Unfortunately
this means the biological conclusions drawn from
the Delta of today may not be relevant a decade
from now (e.g., trophic web shift caused by overbite
clams), especially as invasions continue. Nonetheless,
the invasive and the few remaining native fish
predators in the Delta are generalists that likely
consume whichever fish prey are locally available. Given that invasives are the most abundant fish
species in the Delta, predators appear to prey most
heavily on these species—as expected of generalist
predators. However, the predator-fish prey database Although it is beyond the scope of this study,
Grossman et al. (2013) described a variety of
potential methods for quantifying the effects of
piscine predators on salmonid populations in the
Delta, including modeling, bioenergetics, direct
experimentation, and prey tagging studies. These
methods apply equally well to other predator–prey
interactions. Lindley and Mohr (2003) and Hendrix http://dx.doi.org/10.15447/sfews.2015v14iss2art8 15 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 REFERENCES Adair R, Sullivan P. 2013. Sea lamprey control in the
Great Lakes 2012. Annual report to the Great Lakes
Fishery Commission [Internet]. Ann Arbor (MI): Great
Lakes Fishery Commission. [accessed 2016 May 05];
98 p. http://www.glfc.org/sealamp/ Adkins JY, Roby DD, Lyons DE, Courtot KN, Collis K,
Carter HR, Shuford WD, Capitolo PJ. 2014. Recent
population size, trends, and limiting factors for the
double-crested cormorant in western North America. J Wildl Manage 78:1131–1142. doi: http://dx.doi. org/10.1002/jwmg.737 Ahrens RNM, Walters CJ, Christensen V. 2012. Foraging
arena theory. Fish Fisheries 13:41-59. doi: http://dx.doi. org/10.1111/j.1467-2979.2011.00432.x 16 JULY 2016 Federal Register. 2012. Notice of intent to prepare
an Environmental Impact Statement for proposed
strategies for Lake Trout population reductions to
benefit native fish species, Flathead Lake, Montana. [accessed 2016 May 05]. https://www.federalregister. gov/articles/2012/06/05/2012-13557/notice-of-intent-
to-prepare-an-environmental-impact-statement-for-
proposed-strategies-for-lake-trout Adrean LJ, Roby DD, Lyons DL, Collis K, Evans AF. 2012. Potential effects of management on Caspian tern
Hydroprogne caspia predation on juvenile salmonids at a
colony in San Francisco Bay, California. Trans Am Fish
Soc 141:1682-1696. Baerwald MR, Schreier BM, Schumer G, May B. 2012. Detection of threatened Delta Smelt in the gut
contents of the invasive Mississippi Silverside in the
San Francisco Estuary using taqman assays. Trans
Am Fish Soc 141:1600-1607. doi: http://dx.doi.org/
10.1080/00028487.2012.717521 Brodin T, Fick J, Johsson M, Klaminder J. 2013. Dilute
concentrations of a psychiatric drug alter behavior of
fish from natural populations. Science 339:814-815. [BDCP] Bay Delta Conservation Plan. 2013. Chapter 3.4. Conservation measures. [accessed 2016 May 05] http://
baydeltaconservationplan.com/EnvironmentalReview/
EnvironmentalReview/2013-2014PublicReview/2013Publ
icReviewDraftBDCP.aspx Brooks ML, Fleishman E, Brown LR, Lehman PW, Werner I,
Scholz N, Mitchelmore C, Lovvorn JR, Johnson ML,
Schlenk D, van Drunick S, Drever JI, Stoms DM,
Parker E, Dugdale R. 2012. Life histories, salinity
zones, and sublethal contributions of contaminants
to pelagic fish declines illustrated with a case study
of San Francisco Estuary, California, USA. Estuaries
Coasts 35:603–621. doi: http://dx.doi.org/10.1007/
s12237-011-9459-6 Beamesderfer RCP. 2000. Managing fish predators and
competitors: deciding when intervention is effective
and appropriate. Fisheries 25:18-23. doi: http://dx.doi. org/10.1577/1548-8446(2000)025<0018:MFPACD>2.0
.CO;2 Brown L, May J. 2006. Variation in spring nearshore
resident fish species composition and life histories in
the lower Sacramento-San Joaquin Watershed and Delta
(California). San Franc Estuary Watershed Sci 4(2). doi:
http://escholarship.org/uc/item/09j597dn Baxter R, Breuer R, Brown L, Conrad L, Feyrer F, Fong S,
Gehrts K, Grimaldo L, Herbold B, Hrodey P, Mueller-
Solger A, Sommer T, Souza, K. 2010. SAN FRANCISCO ESTUARY & WATERSHED SCIENCE Conrad L, Bibian AJ, Weinersmith K. DeCarion D,
Young M, Crain P, Hestire E, Santose M. Sih A. 2016. Novel species interactions in a highly modified
estuary: association of Largemouth Bass with Brazilian
Waterweed Egeria densa. Trans Am Fish Soc 145:249-
263 doi: http://dx.doi.org/10.1080/00028487.2015.111
4521 Carthey AJ, Banks PB. 2014. Naiveté in novel ecological
interactions: lessons from theory and experimental
evidence. Biol Rev 89:932–949. doi: http://dx.doi.org/10.1111/brv.12087 [CDFG] California Department of Fish and Game. 2011. Report and recommendation to the Fish and
Game Commission in support of a proposal to revise
sportfishing regulations for striped bass. [Internet]. Sacramento (CA): California Department of Fish
and Wildlife. [accessed 2016 May 05]. http://www. endangeredspecieslawandpolicy.com/files/2011/01/
SB-Staff-Report-1---5-11.pdf Corse WA, Metter E. 1980. Economics, adult feeding and
larval growth of Rana catesbeiana on a fish hatchery. J Herp 14:231-238. Crain PK, Moyle PB. 2011. Biology, history, status
and conservation of Sacramento Perch, Archoplites
interruptus. San Franc Estuary Watershed Sci 9(1). doi: http://dx.doi.org/10.15447/sfews.2011v9iss1art5 [CDFW] California Department of Fish and Wildlife. 2013. Fall midwater trawl. [accessed 2016 May 05]. Sacramento (CA): California Department of Fish
and Wildlife. http://www.dfg.ca.gov/delta/projects. asp?ProjectID=FMWT DeAngelis DL, Goldstein RA, O’Neill RV. 1975. A model
for trophic interaction. Ecology 56:881-892. Davis JP, Schultz ET, Vokoun JC. 2012. Striped Bass
consumption of Blueback Herring during vernal riverine
migrations: does relaxing harvest restrictions on a
predator help conserve a prey species of concern? Mar
Coastal Fish: Dyn Manage Ecosys Sci 4(1):239–251. doi: http://dx.doi.org/10.1080/19425120.2012.675972 Carpenter SR, Kitchell JF, editors. 1993. The trophic
cascade in lakes. New York (NY): Cambridge University
Press. 385 p. Cavallo B, Merz J, Setka J. 2012. Effects of predator and
flow manipulation on Chinook fish (Oncorhynchus
tshawytscha) survival in an imperiled estuary. Environ
Biol Fish 96:393-403. doi: http://dx.doi.org/10.1007/
s10641-012-9993-5 Dege M, Brown L. 2004. Effect of outflow on spring and
summertime distribution and abundance of larval and
juvenile fishes in the upper San Francisco Estuary. Am
Fish Soc Symp 39:49–65. Cloern JE, Jassby AD. 2012. Drivers of change in
estuarine-coastal ecosystems: discoveries from four
decades of study in San Francisco Bay. Rev Geophys
50:1-33. doi: http://dx.doi.org/10.1029/2012RG000397 [DSC] Delta Stewardship Council. 2013. Chapter 4:
Protect, restore, and enhance the Delta ecosystem. In:
Bay–Delta Conservation Plan. Sacramento (CA): Delta
Stewardship Council. [accessed 2016 May 05]. http://
baydeltaconservationplan.com/EnvironmentalReview/
EnvironmentalReview/2013-2014PublicReview/2013Pub
icReviewDraftBDCP.aspx Connon RE, Geist J, Pfeiff J, Loguinov A, D’Abronzo L,
Wintz H, Vulpe C, Werner I. 2009. REFERENCES Interagency
Ecological Program, 2010 pelagic organism decline work
plan and synthesis of results. [Internet]. [accessed 2016
May 05]; 259 p. http://www.science.calwater.ca.gov/pod/
pod_index.html Brown LR, Michniuk D. 2007. Littoral fish assemblages
of the alien-dominated Sacramento-San Joaquin
Delta, California, 1980-1983 and 2001-2003. Estuaries
Coasts 30:186-200. doi: http://dx.doi.org/10.1007/
s12237-011-9459-6 Bennett WA. 1993. Interaction of food limitation,
predation, and anthropogenic intervention on
larval striped bass in the San Francisco Bay estuary
[dissertation]. [Davis (CA)]; University California Davis. 112 p. Brown L, Kimmerer W, Conrad L, Lesmeister L, Mueller–
Solger A. 2016. Delta food webs, past and present. San
Francisco Estuary and Watershed Science, forthcoming. Bennett WA. 2005. Critical assessment of the Delta Smelt
population in the San Francisco Estuary, California. San
Franc Estuary Watershed Sci (3)2. doi: http://dx.doi. org/10.15447/sfews.2005v3iss2art1 Bryant MD, Arnold J. 2007. Diets of age-0 striped bass in
the San Francisco estuary 1973-2002. Cal Fish Game
93:1-22. Bury RB. 1986. Feeding ecology of the turtle, Clemmys
marmorata. J Herp 20:515-521. Bestgen KR, Walford CD, Hill AA, Hawkins JA. 2007. Native fish responses to removal of non-native predator
fish in the Yampa River, Colorado. Denver (CO): U.S. Fish Wildlife Service, Upper Colorado River Endangered
Fish Recovery Program [Internet]. [accessed 2016
May 05]; 42 p. http://www.coloradoriverrecovery.org/
documents-publications/technical-reports/nonnative-fish-
management.html Carey MP, Sanderson BL, Barnas KA, Olden JD. 2012. Native invaders — challenges for science, management,
policy, and society. Front Eco Environ 10:373-381. doi:
http://dx.doi.org/10.1890/110060 17 http://dx.doi.org/10.15447/sfews.2015v14iss2art8 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 JULY 2016 Draulans D. 1988. Effects of fish-eating birds on freshwater
fish stocks—an evaluation. Biol Cons 44:251-263. Gerking SD. 1994. Feeding ecology of fish. San Diego
(CA): Academic Press. 419 p. Draulans D. 1988. Effects of fish-eating birds on freshwater
fish stocks—an evaluation. Biol Cons 44:251-263. Grossman GD. 2014. Not all drift feeders are trout: a short
review of fitness-based habitat selection models for
fishes. Environ Biol Fish 97:465-473. doi: http://dx.doi. org/10.1007/s10641-013-0198-3 Dux AM, Guy CS, Fredenberg WA. 2011. Spatiotemporal
distribution and population characteristics of a
nonnative lake trout population, with implications for
suppression. North Am J Fish Manage 31:187-196. doi:
http://dx.doi.org/10.1080/02755947.2011.562765 Grossman GD, Petty JT, Ratajczak RE, Hunter M,
Peterson JT, Grenouillet G. 2006. Population dynamics
of mottled sculpin (Pisces) in a variable environment:
information theoretic approaches. Ecol Monogr 76:217-
234. doi: http://dx.doi.org/10.1890/04-1623 Essington TE, Hansson S. 2004. Predator-dependent
functional responses and interaction strengths in a
natural food web. Can J Fish Aquat Sci 61:2215-2226. doi: http://dx.doi.org/10.1139/f04-146 Evans AF, Roby D, Collis K, Cramer BM, Sheggeby JA. Adrean LJ, Battaglia DS, Lyons DE. 2011. Recovery
of coded wire tags at a Caspian tern colony in San
Francisco Bay: a technique to evaluate impacts of avian
predation on juvenile salmonids. North Am J Fish
Manage 31:79–87. doi: http://dx.doi.org/10.1080/02755
947.2011.562429 Grossman GD, Nuhfer A, Zorn T, Sundin G, Alexander G. 2012. Population regulation of brook trout (Salvelinus
fontinalis) in Hunt Creek Michigan: a 50-year
study. Freshw Biol 57:1434-1448. doi: http://dx.doi. org/10.1111/j.1365-2427.2012.02806.x Grossman G, Essington T, Johnson B, Miller J, Monsen N,
Pearsons T. 2013. Effects of fish predation on salmonids
in the Sacramento River–San Joaquin Delta and
associated ecosystems. Panel final report [Internet]. [cited 2016 May 05]: 71 p. Sacramento (CA): California
Department Fish Wildlife, Delta Stewardship Council,
and National Marine Fisheries Service. http://www.dfg.ca.gov/erp/predation.asp Ferrari MCO, Ranåker L, Weinersmith L,Young MJ, Sih A,
Conrad JL. 2014. Effects of turbidity and an invasive
waterweed on predation by introduced largemouth
bass Environ Biol Fish 97:79-90. doi: http://dx.doi. org/10.1007/s10641-013-0125-7 Feyrer F, Herbold B, Matern SA, Moyle PB. 2003. Dietary
shifts in a stressed fish assemblage: consequences
of a bivalve invasion in the San Francisco Estuary:
Environ Biol Fish 67: 277–288. doi: http://dx.doi. org/10.1023/A:1025839132274 Grassie C, Braithwaite V, Nilsson J, Nilsen T, Teien H-C,
Handeland S, Stefansson, Tronci V, Gorissen M, Flik G,
Ebbesson L. 2013. Aluminum exposure impacts brain
plasticity and behavior in Atlantic salmon (Salmo
salar). J Exp Biol 216:3148-3155. doi: http://dx.doi. org/10.1242/jeb.083550 FISHBIO. 2013. SAN FRANCISCO ESTUARY & WATERSHED SCIENCE Linking
mechanistic and behavioral responses to sublethal
esfenvalerate exposure in the endangered Delta
Smelt; Hypomesus transpacificus (family Osmeridae). BMC Genomics 10:608-626. doi: http://dx.doi. org/10.1186/1471-2164-10-608 Demetras J, Huff D, Michel C, Smith J, Cutter G, Hayes S,
Lindley S. 2016. Development of underwater recorders
to quantify predation of juvenile Chinook salmon
(Oncorhynchus tshawytscha) in a river environment. Fish Bull 114:179–185. doi: http://dx.doi.org/10.7755/
FB.114.2.5 Connon RE, Deanovic LA, Fritsch EB, D’Abronzo LS,
Werner I. 2011. Sublethal responses to ammonia
exposure in the endangered delta smelt; Hypomesus
transpacificus (family Osmeridae). Aquat Toxicol
105:369–377. doi: http://dx.doi.org/10.1016/j. aquatox.2011.07.002 Dettinger M, Anderson J, Anderson M, Brown L, Cayan D,
Maurer E. 2016. Climate change and the Delta. San
Francisco Estuary and Watershed Science, submitted. 18 JULY 2016 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 Larson GL, Christie GC, Johnson DA, Koonce JF,
Mullett KM, Sullivan WP. 2003. The history of
sea lamprey control in Lake Ontario and updated
estimates of suppression targets. J. Gr. Lakes Res. 29
(Suppl 1):637-654. Johnson BM. Martinez PJ. 2000. Trophic economics of lake
trout management in reservoirs of differing productivity. North Am J Fish Manage 20:115 131. doi: http://dx.doi. org/10.1577/1548-8659(2002)131<0001:TTIICR>2.0. CO;2 Lepak JM, Fetherman ER, Pate WM, Craft CD, Gardunia EI. 2012. An experimental approach to determine esocid
prey preference in replicated pond systems. Lake Res
Manage 28:224-231. Johnson BM, Martinez PJ, Stockwell JD. 2002. Tracking trophic interactions in coldwater
reservoirs using naturally occurring stable isotopes. Trans Am Fish Soc 131:1-13. doi: http://dx.doi. org/10.1577/1548-8659(2002)131<0001:TTIICR>2.0. CO;2 Lindley S, Mohr MA. 2003. Modeling the effect of
striped bass (Morone saxatalis) on the population
viability of Sacramento River winter-run Chinook fish
(Oncorhynchus tshawytscha). Fish Bull 101:321-331. Johnson BM, Martinez PJ, Hawkins JH, Bestgen KR. 2008. Ranking predatory threats by nonnative fishes in the
Yampa River, CO via bioenergetics modeling. North
Am J Fish Manage 28:1941-1953. doi: http://dx.doi. org/10.1577/M07-199.1 Loboschefsky E, Benigno G, Sommer T, Rose KA, Ginn T,
Massoudieh A, Loge F. 2012. Individual-level and
population-level historical prey demand of San Francisco
Estuary striped bass using a bioenergetics model. San
Franc Estuary Watershed Sci 10(1). doi: http://dx.doi. org/10.15447/sfews.2012v10iss1art3 Kerfoot WC, Sih A. 1987. Predation: direct and indirect
impacts on aquatic communities. Hanover (NH): New
England University Press. 386 p. Luoma S, Moore J, Healey M, Dahm C. 2015. Challenges
facing the Sacramento–San Joaquin Delta: complex,
chaotic or simply cantankerous? San Franc Estuary
Watershed Sci 13(3). doi: http://dx.doi.org/10.15447/
sfews.2015v13iss3art7 Kimmerer WJ, Cowan JH, Miller LW, Rose KA. 2000. Analysis of an estuarine striped bass (Morone saxatillis)
population: influence of density-dependent mortality
between metamorphosis and recruitment. Can J Fish
Aquat Sci 57:478-486. Matern SA, Brown LR. 2005. Invaders eating invaders:
exploitation of novel alien prey by the alien Shimofuri
goby in the San Francisco Estuary, California. Biol Inv
7:497–507. Kimmerer WJ, Brown L, Culberson S, Moyle P,
Nobriga, ML, Thompson J. 2008. Aquatic ecosystems. In: Healey M, editor. 2008. The state of Bay-Delta
science. [accessed 2016 May 05]. Sacramento (CA): Delta
Stewardship Council. p. 73-102. http://www.science.calwater.ca.gov/ Mazur MM, Beauchamp DA. 2006. Linking piscivory to
spatial-temporal distributions of pelagic prey fishes with
a visual foraging model. J Fish Biol 69:151-175. Kuehne LM, Olden JD. 2012. JULY 2016 Predation study report, Don Pedro
Project FERC No. 2299. [accessed 2016 May 05];
71 p. Washington, D.C.: Federal Regulatory Energy
Commission. http://www.donpedro-relicensing.com/
documents.aspx Hansen MJ, Schill D, Fredericks J, Dux A. 2010. Salmonid
predator–prey dynamics in Lake Pend Oreille, ID, USA. Hydrobiologia 650:85-100. Hixon MA, Carr MH. 1997. Synergistic predation, density
dependence, and population regulation in marine fish. Science 277:946-949. Fong S, Connon RE, Louie S, Werner I, Davis J, Smith L,
Connor V. Contaminant effects on California Delta
species and human health. San Francisco Estuary and
Watershed Science, submitted. Hostetter NJ, Evans AF, Cramer BM, Collis K, Lyons DE,
Roby DD. 2015. Quantifying avian predation on fish
populations: integrating predator-specific deposition
probabilities in tag recovery studies. Trans Am Fish Soc
144:410-422. doi: http://dx.doi.org/10.1080/00028487. 2014.988882 Fritsch EB, Connon RE, Werner IE, Davies RE, Beggel SE,
Feng W, Pessah IN. 2013. Triclosan impairs swimming
behavior and alters expression of excitation-contraction
coupling proteins in fathead minnow (Pimephales
promelas). Environ Sci Technol 47:2008−2017. doi:
http://dx.doi.org/10.1021/es303790b 19 http://dx.doi.org/10.15447/sfews.2015v14iss2art8 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE JULY 2016 Nobriga M, Chotkowski M, Baxter R. 2002. Baby steps
toward a conceptual model of predation in the Delta:
preliminary results from the shallow water habitat
predator–prey dynamics study. Delta Interagency
Ecological Program Newsletter [Internet]. [accessed
2016 Jul 15]; 16:19-27. http://www.water.ca.gov/iep/
newsletters/2003/IEPnewsletterFall2002.pdf McIntyre JK, Baldwin DH, Beauchamp DA, Scholz NA. 2012. Low-level copper exposures increase visibility
and vulnerability of juvenile coho salmon to cutthroat
trout predators. Ecol App 22:1460–1471. http://dx.doi. org/10.1890/11-2001.1 Merz JE. 2002a. Seasonal feeding habits, growth,
and movement of steelhead trout in the lower
Mokelumne River. California Cal Fish Game 88:95-
111. [accessed 2016 Jul 16] http://www.genidaqs.net/
reports/2002/2002_season_feed_habits_streelhead.pdf Nobriga M, Loboschefsky E, Feyrer F. 2013. Common
predator, rare prey: exploring juvenile Striped Bass
predation on Delta Smelt in California’s San Francisco
Estuary. Trans Am Fish Soc 142:1563-1575. doi: http://dx.doi.org/10.1080/00028487.2013.820217 Merz JE. 2002b. Comparison of diets of prickly sculpin
and juvenile fall-run Chinook salmon in the Lower
Mokelumne River, California. Southwest Nat 47:195-
204. [accessed 2016 Jul 16] http://www.jstor.org/
stable/3672907 O’Rear TA. 2007. Diet of an introduced estuarine
population of white catfish in California. MSc thesis. [Davis (CA)]: University California, Davis. 58 p. Porter R. 2010. Report on the predation index, predator
control fisheries, and program evaluation for the
Columbia River Basin Experimental Northern
Pikeminnow Management Program Annual Report. [accessed 2016 May 05]. Portland (OR): United States
Department of Energy, Bonneville Power Administration. http://www.pikeminnow.org/project-reports-2/
annual-reports Mittelbach GG, Persson L. 1998. The ontogeny of piscivory
and its ecological consequences. Can J Fish Aquat Sci
55:1454-1465. Moyle PB, Cech JJ, Jr. 2004. Fishes: an introduction to
ichthyology. Upper Saddle River (NJ): Prentice Hall. 726 p. Moyle PB, Kiernan JD, Crain PK, Quiñones RM. 2013. Climate change vulnerability of native and alien
freshwater fishes of California: a systematic assessment
approach. PLoS ONE 8(5): e63883
doi: http://dx.plos.org/10.1371/journal.pone.0063883 Riensche DL, Elliott ML, Euing SH. 2012. Breeding
status, nesting densities and diet trends of two
endangered California least tern colonies. J Environ
Sci Eng B1:1135-1145. [accessed 2016 Jul 16] http://
www.davidpublishing.com/davidpublishing/Upfi
le/1/21/2013/2013012102671528.pdf Mueller GA. 2005. Predatory fish removal and native fish
recovery in the Colorado River mainstem: what have we
learned? Fisheries 30:10–19. Sabal M, Hayes S, Merz J, Setka J. 2016. Habitat
alterations and a nonnative predator, the striped bass,
increase native Chinook Salmon mortality in the Central
Valley, California. North Am J Fish Manage 36:309–320. doi: http://dx.doi.org/10.1080/02755947.2015.1121938 [NRC] National Research Council. 2010. SAN FRANCISCO ESTUARY & WATERSHED SCIENCE Prey naivety in the
behavioral responses of juvenile Chinook fish
(Oncorhynchus tshawytscha) to an invasive predator. Freshw Biol 57:1126-1137. doi: http://dx.doi. org/10.1111/j.1365-2427.2012.02776.x McGourty CR, Hobbs JA, Bennett WA, Green PG, Hwang
H-N, Ikemiyagi N, Lewis L, Cope JM. 2009. Likely
population-level effects of contaminants on a resident
estuarine fish species: comparing Gillichthys mirabilis
population static measurements and vital rates in
San Francisco and Tomales Bays. Estuaries Coasts
32:1111–1120. Kolar CS, Courtneay WR, Jr, Nico LG. 2010. Managing
undesired and invading fishes. In: Hubert WA, Quist MC,
editors. Inland fisheries management in North America. 3rd ed. Bethesda (MD): American Fisheries Society
p. 213-260. McIntyre JK, Baldwin DH, Meador JP, Scholz NL. 2008. Chemosensory deprivation in juvenile coho salmon
exposed to dissolved copper under varying water
chemistry conditions. Environ Sci Technol 42:1352–
1358. http://dx.doi.org/abs/10.1021/es071603e Kushlan JA, Hancock JA. 2005. The Herons. Oxford (UK):
Oxford University Press. 456 p. 20 JULY 2016 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE VOLUME 14, ISSUE 2, ARTICLE 8 Thomas JL. 1967. The diet of juvenile and adult striped
bass, Roccus saxatilis, in the Sacramento–San Joaquin
river system. Cal Fish Game 53:49-62. Schoellhamer D, Wright S, Monismith S, Bergamaschi B. Recent advances in understanding flow dynamics
and transport of water-quality constituents in the
Sacramento-San Joaquin River Delta. San Francisco
Estuary and Watershed Science, submitted. Tucker ME, Williams CM, Johnson RR. 1998. Abundance,
food habits, and life history aspects of Sacramento
squawfish and striped bass at the Red Bluff Diversion
Complex, including the Research Pumping Plant,
Sacramento River, California, 1992-1996. [accessed 2016
May 05]. Red Bluff (CA): U.S. Fish Wildlife Service, Red
Bluff Research Pumping Plant Report Series, Volume 4. http://www.usbr.gov/mp/TFFIP/redbluff/redbluffreport/
index.html Sih A, Bolnick D, Luttbeg B, Orrock JL, Peacor S,
Pintor LM, Preisser E, Rehage J, Vonesh J. 2010. Predator–prey naivete, antipredator behavior, and the
ecology of predator invasions. Oikos 119:610–621. doi:
http://dx.doi.org/10.1111/j.1600-0706.2009.18039.x Skorupski JA, Breen MJ, Monroe L. 2012. Native fish
response to nonnative fish removal from 2005-2008
in the Middle Green River, Utah [Internet]. [accessed
2016 May 05]. Denver (CO): Upper Colorado River
Endangered Fish Recovery Program, U.S. Fish and
Wildlife Service. http://www.coloradoriverrecovery.org/
documents-publications/technical-reports/nonnative-fish-
management.html Turner JL, Kelley DW, editors. 1966. Bulletin 136. Ecological studies of the Sacramento-San Joaquin
Estuary, part II: fishes of the Delta. Turner JL. 1966a. Distribution and food habits of ictalurid
fishes in the Sacramento-San Joaquin Delta. Turner JL,
Kelley DW, editors. Bulletin 136. Ecological studies of
the Sacramento-San Joaquin Estuary. Part II: fishes of
the Delta. Sacramento (CA): California Department of
Fish and Game. p. 130-143. Sloman KA, Wilson RW. 2006. Anthropogenic impacts
upon behaviour and physiology. Behaviour and
physiology of fish. Vol 24 [Internet]. p. 413-468. doi:
http://dx.doi.org/10.1111/j.1365-2427.2006.01661.x Turner JL. 1966b. Distribution and food habits of
centrarchid fishes in the Sacramento-San Joaquin Delta. Turner JL, Kelley DW, editors. Bulletin 136. Ecological
studies of the Sacramento-San Joaquin Estuary. Part
II: fishes of the Delta. Sacramento (CA): California
Department of Fish and Game. p. 144-153. Smith BR, Tibbles JR. 1980. Sea lamprey (Petromyzon
marinus) in Lakes Huron, Michigan, and Superior:
history of invasion control, 1936-78. Can J Fish Aquat
Sci 37:1780-1808. Sommer T, Armor C, Baxter R, Breuer R, Brown L,
Chotkowski M, Culberson S, Feyrer F, Gingras M,
Herbold B, Kimmerer W, Mueller–Solger A, Nobriga M,
Souza K. 2007. The collapse of pelagic fishes in the
upper San Francisco Estuary. Fisheries 32:270-277. JULY 2016 A scientific
assessment of alternatives for reducing water
management effects on threatened and endangered fishes
in California’s Bay–Delta. Washington, D.C.: National
Academies Press. 109 p. Sandahl JF, Baldwin DH, Jenkins JJ, Scholz N. 2007. A sensory system at the interface between urban
stormwater runoff and salmon survival. Environ Sci
Technol 41:2998-3004. doi: http://dx.doi.org/10.1021/
es062287r [NRC] National Research Council. 2012. Sustainable water
and environmental management in the California Bay-
Delta. Washington, D.C.: National Academies Press. 271 p. Scharf FS, Juanes F, Rountree RA. 2000. Predator size–prey
size relationships of marine fish predators: interspecific
variation and effects of ontogeny and body size on
trophic-niche breadth. Mar Ecol Prog Ser 208:229-248. doi: http://dx.doi.org/10.3354/meps208229 Nobriga ML, Feyrer F. 2007. Shallow-water piscivore-prey
dynamics in California’s Sacramento-San Joaquin Delta. San Franc Estuary Watershed Sci 5(2). doi:
htt
//d d i
/10 15447/ f
2007 5i
2
t4 http://dx.doi.org/10.15447/sfews.2007v5iss2art4 21 http://dx.doi.org/10.15447/sfews.2015v14iss2art8 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE JULY 2016 Halstead B. U.S. Geological Survey, Western Ecological
Research Center, Dixon, CA. Email dated 2015 May 16 to
G. Grossman about predation in the Delta. Whipple A, Grossinger RM, Rankin D, Stanford B,
Askevold R. 2012. Sacramento–San Joaquin Delta
historical ecology investigation: exploring pattern and
process. Richmond (CA): San Francisco Estuary Institute. 225 p. Hendrix N. 2013. OBAN model. Presented at: State of the
science workshop on fish predation on Central Valley
salmonids in the Bay-Delta Watershed; 2013 Jul 22–23;
Davis, CA. [accessed 2016 May 05]. http://www.dfg. ca.gov/erp/predation.asp Whitley SN, Bollens SM. 2014. Fish assemblages across
a vegetation gradient in a restoring tidal freshwater
wetland: diets and potential for resource competition. Environ Biol Fish 97:659–674. doi: http://dx.doi. org/10.1007/s10641-013-0168-9 Moyle PB. Peter Moyle, University of California, Davis. In-person conversation with G. Grossman on 2015 May
14 about otter populations in the Delta. Wiens J, Grenier L, Grossinger R, Healey M. 2016. The
Delta as changing landscapes. San Franc Estuary
Watershed Sci 14(2). doi: http://dx.doi.org/10.15447/
sfews.2016v14iss2art9 Smith JM, Huff D, Michel C, Quinn T, Lindley S, Hayes S. 2015. Who eats who? Genetic diet analysis of non-
native piscine predators in the San Joaquin River. Unpublished data sent to G. Grossman via email on 2015
May 27 about predation on Delta fishes. Winder M, Jassby AD, MacNally R. 2011. Synergies
between climate anomalies and hydrological
modifications facilitate estuarine biotic invasions. Ecol Lett 14:749–757. doi: http://dx.doi. org/10.1111/j.1461-0248.2011.01635.x Young M. 2015. Matthew Young, University of California,
Davis, CA. Unpublished data sent to G. Grossman via
email on 2015 June 08 about predation on Delta fishes. Wylie GD, Casazza ML, Carpenter M. 2003. Diet of
bullfrogs in relation to predation on giant garter snakes
at Colusa National Wildlife Refuge. Cal Fish Game
89:139-145. Zeug S. 2015. Steve Zeug, Cramer Fish Sciences, Auburn,
CA. Unpublished data sent to G. Grossman via email on
2015 June 15 about predation on Delta fishes. Zale AZ, Parrish DL, Sutton TM, editors. 2013. Fisheries
techniques, 3rd ed. Bethesda (MD): American Fisheries
Society. 1,009 p. 3
http://dx.doi.org/10.15447/sfews.2015v14iss2art8 SAN FRANCISCO ESTUARY & WATERSHED SCIENCE doi:
http://dx.doi.org/10.1080/00028487.2011.630280 Tyus HM, Saunders JF. 2000. Nonnative fish control and
endangered fish recovery: lessons from the Colorado
River. Fisheries 25:17-24. doi: http://dx.doi.org/
10.1577/1548-8446(2000)025<0017:NFCAEF>2.0. CO;2 Underwood EC, Mulitsch MJ, Greenberg JA, Whiting, ML,
Ustin SL, Kefauver SC. 2006. Mapping invasive aquatic
vegetation in the Sacramento–San Joaquin Delta using
hyperspectral imagery. Environ Monit Assess 121:47-64. doi: http://dx.doi.org/10.1007/s10661-005-9106-4 Stevens DL. 1966. Food habits of Striped Bass (Roccus
saxatilis) in the Sacramento-San Joaquin Delta. In:
Turner JL, Kelley DW, editors. Bulletin 136. Ecological
studies of the Sacramento-San Joaquin Estuary. Part
II: fishes of the Delta. Sacramento (CA): California
Department of Fish and Game. p. 68-96. [USFWS] U.S. Fish Wildlife Service. 2012. Nonnative fish
management. [accessed 2016 May 05]; http://www. coloradoriverrecovery.org/general-information/program-
elements/nonnative-fish-management.html Syslo JM, Guy CS, Bigelow PE, Doepke PD, Philip D,
Ertel BD, Koel TM. 2011. Response of non-native lake
trout (Salvelinus namaycush) to 15 years of harvest in
Yellowstone Lake, Yellowstone National Park. Can J Fish
Aquat Sci 68:2132-2145. doi: http://dx.doi.org/10.1139/
f2011-122 22 JULY 2016 NOTES Brandl S, Schreier B, Conrad JL. Schumer G, May B,
Baerwald M. 2015. Enumerating incidence of predation
on Chinook and other species in the North Delta using
a genetic approach. Presented at: 2015 Annual IEP
Workshop; 2015 Mar 18–20; Folsom, CA. Brown L. 2013. Ecological context. Presented at: State
of the science workshop on fish predation on Central
Valley salmonids in the Bay-Delta Watershed; 2013 Jul
22–23; Davis, CA. [accessed 2016 May 05]. http://www. dfg.ca.gov/erp/predation_presentations.asp Conrad L, Kelly L. Weinersmith KL, Bibian A, Young M,
de Carion D, Sih A. 2013. Largemouth bass. Presented
at: State of the science workshop on fish predation on
Central Valley salmonids in the Bay-Delta Watershed;
2013 Jul 22–23; Davis, CA. [accessed 2016 May 05]. http://www.dfg.ca.gov/erp/predation_presentations.asp 23 http://dx.doi.org/10.15447/sfews.2015v14iss2art8
|
https://openalex.org/W4229528132
|
https://www.qeios.com/read/DWMUTD/pdf
|
English
| null |
H2BS1 wt Allele
|
Definitions
| 2,020
|
cc-by
| 79
|
Qeios · Definition, February 2, 2020 Open Peer Review on Qeios H2BS1 wt Allele National Cancer Institute National Cancer Institute Qeios ID: DWMUTD · https://doi.org/10.32388/DWMUTD Source National Cancer Institute. H2BS1 wt Allele. NCI Thesaurus. Code C162839. Human H2BS1 wild-type allele is located in the vicinity of 21q22.3 and is approximately 1
kb in length. This allele, which encodes histone H2B type F-S protein, plays a role in
antimicrobial defense responses and chromatin condensation. Qeios ID: DWMUTD · https://doi.org/10.32388/DWMUTD 1/1
|
https://openalex.org/W3155730921
|
https://www.researchsquare.com/article/rs-248748/v1.pdf?c=1631876413000
|
English
| null |
Influence of Back Contact Annealing Temperature in the mc-Si&nbsp;Solar Cell Fabrication Process
|
Research Square (Research Square)
| 2,021
|
cc-by
| 4,484
|
In§uence of Back Contact Annealing Temperature in
the mc-Si Solar Cell Fabrication Process
Aravindan Gurusamy ( aravindanvpt@gmail.com )
Sri Sivasubramaniya Nadar College of Engineering https://orcid.org/0000-0002-0415-3261
S S
l S. Sanmugavel
SSN college of Engineering
S. G. Nagarajan
SSN College of Engineering
V. Kesavan
SSN College of ENgineering
M. Srinivasan
SSN College of Engineering
P. Ramasamy
SSN COllege of Engineering Research Article License: This work is licensed under a Creative Commons Attribution 4.0 International License. R
d F ll Li Keywords: Directional Solidification Process, Multi crystalline Silicon solar cell. Keywords: Directional Solidification Process, Multi crystalline Silicon solar cell. Fabrication Process
G. Aravindan1, S. Sanmugavel1, S. G. Nagarajan1, V. Kesavan1, M. Srinivasan1 and P. Ramasamy1*
1Research Centre, Sri Sivasubramaniya Nadar College of Engineering, Chennai.
*Corresponding author Email: aravindanvpt@gmail.com G. Aravindan1, S. Sanmugavel1, S. G. Nagarajan1, V. Kesavan1, M. Srinivasan1 and P. Ramasamy1*
1Research Centre, Sri Sivasubramaniya Nadar College of Engineering, Chennai. 1Research Centre, Sri Sivasubramaniya Nadar College of Engineering, Chennai. Abstract: The boron doped multi-crystalline silicon (mc-Si) ingot was grown using the directional
solidification process. Grown ingots were converted into bricks and then to wafers. We have
fabricated silicon solar cells from the multi-crystalline silicon wafers. The minority carrier
lifetime of the wafers is around 15-25 s. Annealing was made after back and front contact
during the fabrication process. The effect of back contact annealing temperature has been
investigated. Annealing the device at 5830C for 5 sec gives better results. Typical open circuit
voltage (Voc) of the devices is around ~540-550mV. The best cell had a power conversion
efficiency of ~9 % with a typical acceptor doping density ~ 2.35 E+15 per cm3 (The devices
reported here do not have AR coating layer, no passivation was done and the surfaces are also
not textured). 1. INTRODUCTION For normal growth of this technological word, energy conversion is very crucial. Among
the renewable energy sources, eco-friendly solar cells technology is most important one. In this
photovoltaic (PV) market 95 % is occupied by the crystalline silicon (c-Si) solar cells. In the
c-Si market mc-Si solar cells occupies 62 % due to low cost and high efficiency. 70 % of global
module production is by China and Taiwan. Development of mc-Si solar cells is very important
due to the lower material cost (20 to 30 %) than mono-crystalline silicon [1]. Normally mc-Si
ingot is grown by the directional solidification (DS) process because of low cost, mass
production and simple operating process compared to other mass production method like
Czochralski (Cz) growth process. We have grown mc-Si ingot by using the DS process. The
grown ingots (Fig.1b) are converted to brick (Fig.1c) then to wafers (Fig.1d). Prepared wafers
are subjected to cell making. During the cell making the metallization is crucial one, because
it affects the solar cell’s efficiency. Currently many researchers are attempting optimization of 1 metallisation. Low-cost and low-temperature chemical oxide passivation process was
investigated by Yadav et al, thus improving the conversion efficiency by 0.3 % [2]. Meili Cui
et all reduced Fe concentration and improved lifetime by the low temperature annealing process
after the diffusion [3]. C Chan analysed the post-firing thermal process on PERC solar cells
[4]. Ana Peral et al studied the Impact of Extended Contact Cofiring on multicrystalline Silicon
Solar Cell [5]. Catherine E. Chan et al investigated the suppression of Carrier induced
degradation of PERC mc-Si solar cells [6]. Shiliang Wu et al investigated the electrical
properties of mc-Si solar cell by the different front contact firing [7]. Extended co-firing was
done by Ana Peral et al [8]. For all type of solar cell making optimization of the Series and
Shunt resistance is needed. In this work we investigate on the influence of back contact
annealing temperature and time. During the device fabrication process we vary the back contact
annealing temperature and find out the suitable annealing temperature. Fabricated solar cells
are characterized by IV, QE and Capacitance measurements. Directional Solidification Process: We have grown mc-Si ingot by using the DS process. The DS furnace is shown in Fig.1a. In this (DS) process there are five steps: First step is heating the furnace, before heating the
furnace the feed stock materials are loaded in the quartz crucible. Second step is melting;
furnace is heated above the silicon melting point. After melting silicon feed stock materials,
furnace is maintained for a few hours for homogenisation of molten silicon. Third step is
crystallization, after the melting, furnace temperature is reduced for crystallization of molten
silicon. Fourth step is annealing process; mc-Si ingot is annealed at suitable temperature for a
particular time. Then finally (Fifth step) the furnace is cooled. Harvested ingots are converted
to brick and bricks are converted to wafer. The wafer size is 34 mm* 34 mm, thickness of the
wafer is 300 micron. Initially our wafers are subjected to lifetime measurement, after the
cleaning process, the life time of the wafers is 15 and 25 micro sec. 2 2 FIGURE 1a. Directional Solidification Furnace FIGURE 1a. Directional Solidification Furnace FIGURE 1a. Directional Solidification Furnace 2. FABRICATION PROCESS STEPS
FIGURE 1b. As-grown
Multi-crystalline Silicon
ingot
FIGURE 1c. As-Cut
Brick from the
grown ingot
FIGURE 1d. Multi-
Crystalline silicon wafer FIGURE 1b. As-grown
Multi-crystalline Silicon FIGURE 1c. As-Cut
Brick from the FIGURE 1b. As-grown
Multi-crystalline Silicon
i
t FIGURE 1d. Multi-
Crystalline silicon wafer 2. FABRICATION PROCESS STEPS 2.1 Saw Damage Removal (SDR) Etching The as cut wafers are very rough. Using a solution of NaOCl, KOH and H2O the
samples were etched for 15 min at 80 degree Celsius in an effort to reduce the roughness caused
by the slicing of the wafers. Etching rate of this SDR etching is 1.4 micro metre per min. After
the SDR etching process the thickness of that sample was calculated by using the mass
difference method. The amount of material removed is roughly 20 micrometre. After the SDR
etching the samples are cleaned by the RCA1 and RCA2 cleaning process. Before starting the
fabrication of solar cells using the silicon wafers, all the organic and ionic impurity present on
the surface of the wafers was removed. 2.2 First Oxidation The oxidation was done by using the oxidation furnace. This oxidation protects the back
surface during the n+ diffusion. This process was done for 4 hr at 1050o C with 1slpm O2 gas
flow. The oxide thickness is around 200nm. After the oxidation process SiO2 is removed from
one side by using the HF etching. The oxide is removed from the side where we will do the
diffusion. During the etching process we used Dilute HF solution [1(HF): 10(DI water)]. 2. FABRICATION PROCESS STEPS We have done metallization by using the thermal evaporator system. After the
metallization we have annealed following two step annealing process, first annealing is
after the back contact and second annealing is after the front contact. Both annealing
process is done in nitrogen atmosphere by the RTP system. 3 2.6 Metallization Metallization is the end process of solar cell fabrication process. We have made
back and front side contacts in the vacuum evaporation deposition system. The
annealing of the contacts is done in the Rapid thermal Process system. 2.5 Lithography The lithography is done to make small mesas of area 1.1 x1.1 cm2 and 0.49 x 0.49 cm2
on the single wafer. The lithography setup and patterned mc-Si wafer are shown in Fig.2. (a) (b)
FIGURE 2 Lithography (a) Lithography setup (b) Patterned mc-Si wafer (b) (a) (a) (b) FIGURE 2 Lithography (a) Lithography setup (b) Patterned mc-Si wafer 2.3 Diffusion Process Diffusion process is done to make a P-N junction. The N layer formed on the top of the
P wafer for P-N junction formation is done by using phosphorus solid source. This process was
done for 15 min at 875°C. Before the diffusion, phosphorus sources are activated at 925oC for
8 hours. During the diffusion and activation 1 slpm nitrogen gas flow is maintained. The
thickness of the N-layer formed is 600 nm. After the diffusion, wafers are immersed in a 2%
HF solution to remove the oxides formed on the wafer during diffusion. The side which is
diffused (we call it front side) will form a P2O5 and back is having the oxide grown in first
oxidation process. 4 4 2.4 Second Oxidation This oxidation is done for masking lithography process. Oxidation was done by using
the oxidation furnace. Process is done for 2 hr at 700 o C. During the oxidation oxygen was
admitted at 1 slpm. Approximate thickness of the oxide layer formed is 20 nm. 2.7 Back side contact By using the vacuum system we deposited Al on the back of the wafer. During the back
contact edges are prevented from getting deposited by covering them with the mica sheet. Fig.3a. shows the mc-Si wafer after the back side contact. After the back contact wafers are 5 annealed by using the RTP system. Our samples are subjected to different back contact
annealing, the details are listed in the Table.1. Table.1 Back contact annealing details. Table.1 Back contact annealing details. Sample
Name
Annealing Temperature and Time
(Nitrogen atmosphere)
Set 1
A
590 C 5 min
B
600 C 5 min
Set 2
C
590 C 5 min twice
D
600 C 5 min twice
Set 3
E
610 C 5 min then 575 C 5 min
Set 4
F
583 C 5 sec
G
594 C 5 sec 2.8 Front side contact The vacuum system is used to make as stack of Ti and Ag on the Top of the wafer inside
the MESA’s. The front contact deposition is done through a mask (Compatible to the
Lithography mask) which will allow deposition through it such that bus bar and Fingers are
deposited on it (Fig. 3b). Fig.3c shows the mc-Si wafer after the front side contact. After the
front contacts are made the sample is annealed by using the RTP system. Our sample is
annealed at 285o C for 20 sec. (a) (b)
(C) (C) (a) (C) (b) (b) (a) 6 6 FIGURE 3 Front contact (a) mc-Si wafer after the Front side contact (b) Metal mask (c) mc-
Si wafer after the Back side contact 3 RESULT AND DISCUSSION During the device fabrication, after the back contact and after the front contact,
annealing process is very crucial. Annealing temperature, time period and ramp up time
influence the metallization part diffusing from one side to another side through the grain
boundary of the mc-Si wafer. The details of the back contact annealing temperature are listed
in table.1. After the metallization our devices are subjected to dark and light IV measurement. 7 FIGURE 4 Dark IV curve of various annealing experiments. A, B, C, D, E, F and G are
corresponding to 5900 C 5 min, 6000 C 5 min, 5900 C 5 min two times, 6000 C 5 min two times,
6100 C then 5750 C 5 min, 5830 C 5 sec and 5940 C 5 sec. FIGURE 4 Dark IV curve of various annealing experiments. A, B, C, D, E, F and G are
corresponding to 5900 C 5 min, 6000 C 5 min, 5900 C 5 min two times, 6000 C 5 min two times,
6100 C then 5750 C 5 min, 5830 C 5 sec and 5940 C 5 sec. Fig 4. shows the semi log graph of dark IV curve of various annealing experiments, in each
experiment five devices were tested. The area of 1 and 2 is 1.21 cm2 and 3, 4 and 5 is 0.49 cm2. The mc-Si wafers were subjected to four set of back contact annealing experiments, the details
are listed in the table 1. In first set of experiment the leakage current of Case A is in the range
of 10-6 to 10-4 A and for Case B it is from 10-5 to 10-3A. In second set of experiment the leakage
current of Case C is in the range of 10-5 to 10-3 A and for Case D it is from 10-4 to 10-3 A. In
third set of experiment the leakage current of Case E is in the range of 10-4 to 10-2 A. And in
the fourth set of experiment the leakage current of Case F is in the range of 10-8 to 10-4 A and
for Case G it is from 10-5 to 10-2 A. In all the sets of experiments the leakage current is higher
for higher annealing temperature. This is because of metal part diffused to the opposite side,
that it acts as pipe line from one side to another side. 3 RESULT AND DISCUSSION The better leakage current was obtained
in case F. In case F the leakage current is in the range of 10-8 to 10-4 A. If we increase the 8 temperature or time, the metal parts would be diffused through the grain boundary of the mc-
Si. The shunt resistance of fabricated devices is listed in the table 2. In all the sets of
experiments the shunt resistance is higher in the lower annealing temperature cases. In those
experiments Al spike opposite side through the grain boundary. The maximum shunt resistance
is case F in the order of 107 ohm range. We calculated the shunt resistance from the normal
dark IV curve, it is listed in table 2. Table 2. Shunt Resistance [in ohm] Table 2. Shunt Resistance [in ohm] Table 2. Shunt Resistance [in ohm] Table 2. Shunt Resistance [in ohm] Device
Number
A
B
C
D
E
F
G
1
3.20E+06
6.63E+03
3.33E+03
3.33E+02
5.00E+02
4.00E+04
1.04E+04
2
4.00E+04
4.76E+00
1.25E+03
3.57E+03
2.00E+02
1.25E+03
7.00E+02
3
2.00E+03
2.63E+03
1.59E+03
1.25E+04
7.41E+01
1.03E+07
1.79E+02
4
2.38E+04
8.25E+04
7.14E+03
7.25E+02
1.85E+03
3.77E+05
3.57E+02
5
7.05E+05
3.33E+03
9.52E+03
5.85E+02
3.12E+02
3.00E+04
7.14E+03 9 9 FIGURE 5 Light IV curve of various annealing experiments. A, B, C, D, E, F and G are
corresponding to 5900 C 5 min, 6000 C 5 min, 5900 C 5 min two times, 6000 C 5 min two times,
6100 C then 5750 C 5 min, 5830 C 5 sec and 5940 C 5 sec. FIGURE 5 Light IV curve of various annealing experiments. A, B, C, D, E, F and G are
corresponding to 5900 C 5 min, 6000 C 5 min, 5900 C 5 min two times, 6000 C 5 min two times,
6100 C then 5750 C 5 min, 5830 C 5 sec and 5940 C 5 sec. Light IV of the different annealing experiments was shown in fig.5. In each annealing
experiments, we compared five devices. From the dark IV analysis we observed that shunt
resistance is higher in the case F than other cases. The IV parameter of those curves is listed in
table 3. Table 3A and 3B is comparing the Jsc and Voc of fabricated devices. From all the
experiments the lower annealing experiments give better Jsc and Voc than other cases. Table 10 3C and 3D compares FF and conversion efficiency. In set 2 and Set 4 the lower annealing
temperature gives better FF and conversion efficiency. Form these sets of analysis, the case F
has given better Voc than other. The fill factor of case F is around 0.65 to 0.72 which is high
compared to other cases and hence it leads to the higher efficiency. At higher temperature Al
spiked to other side due to the over firing of wafer, it reduces the shunt resistance. Sticking of
Al on wafer is very poor at lower temperature, it increases the series resistance. If we further
do the series of systematic experiments we can get precise back contact annealing condition. Table 3. IV Parameter Table 3A. Jsc (A/cm2) A
B
C
D
E
F
G
1
13.39
13.39
13.22
9.75
17.19
15.21
15.04
2
11.65
15.21
16.94
11.90
13.64
16.03
14.21
3
12.69
12.90
17.55
12.37
14.57
17.82
13.88
4
10.78
20.18
17.94
16.90
21.43
25.51
18.43
5
21.02
14.10
14.43
18.06
16.63
23.67
18.22
Table 3B. Voc (mV)
A
B
C
D
E
F
G
1
530
327
518
236
540
550
550
2
526
467
518
347
530
550
550
3
516
467
508
317
440
560
490
4
516
367
508
427
540
560
520
5
544
391
508
508
520
560
560
Table 3C. FF
A
B
C
D
E
F
G
1
0.31
0.43
0.60
0.34
0.55
0.65
0.65
2
0.34
0.51
0.61
0.40
0.59
0.66
0.44
3
0.34
0.52
0.57
0.43
0.26
0.72
0.40
4
0.34
0.45
0.49
0.46
0.57
0.63
0.44
5
0.32
0.52
0.54
0.36
0.51
0.69
0.68
Table 3D. Efficiency A
B
C
D
E
F
G
1
13.39
13.39
13.22
9.75
17.19
15.21
15.04
2
11.65
15.21
16.94
11.90
13.64
16.03
14.21
3
12.69
12.90
17.55
12.37
14.57
17.82
13.88
4
10.78
20.18
17.94
16.90
21.43
25.51
18.43
5
21.02
14.10
14.43
18.06
16.63
23.67
18.22 Table 3B. Voc (mV)
A
B
C
D
E
F
G
1
530
327
518
236
540
550
550
2
526
467
518
347
530
550
550
3
516
467
508
317
440
560
490
4
516
367
508
427
540
560
520
5
544
391
508
508
520
560
560 Table 3C. FF
A
B
C
D
E
F
G
1
0.31
0.43
0.60
0.34
0.55
0.65
0.65
2
0.34
0.51
0.61
0.40
0.59
0.66
0.44
3
0.34
0.52
0.57
0.43
0.26
0.72
0.40
4
0.34
0.45
0.49
0.46
0.57
0.63
0.44
5
0.32
0.52
0.54
0.36
0.51
0.69
0.68 Table 3D. Efficiency Table 3D. Efficiency 11 A
B
C
D
E
F
G
1
2.20
1.90
4.10
0.77
5.17
5.46
5.46
2
2.10
3.62
5.36
1.65
4.29
5.89
3.52
3
2.19
3.15
5.03
1.66
1.69
7.24
2.75
4
1.89
3.35
4.41
3.33
6.62
9.07
4.27
5
3.66
2.93
3.93
3.30
4.42
9.23
6.97 3.1 Capacitance Measurement After the device fabrication better efficiency devices are subjected to the capacitance
measurement by using the LCR meter to find Vbi and NA values of our wafers. The capacitance
versus voltage graph is shown in Fig 6 and data listed on Table 4. In order to achieve 9.4E15
atoms/cm3 accepter concentration, 2.3 grams of heavily boron doped silicon wafer was added
for 10 kg feed stock. The equation of the acceptor calculation (NA) is follows: Where Where In the plot 1/C2 Versus V the slope value is K In the plot 1/C2 Versus V the slope value is K In the plot 1/C2 Versus V the slope value is K 𝑁𝐴=
2
𝑞𝜖𝜖0𝑘 Where q = 1.6 E-19 C/F
𝜀𝜀0 = 1.062 E-10 F/m 12 FIGURE 6 Capacitance Measurement FIGURE 6 Capacitance Measurement FIGURE 6 Capacitance Measurement
Table.4. Capacitance Measurement Details
Area
Sample
Name
K
NA
(1/cm^3)
Mobility
(cm2/V S)
0.49
1
5.00E+15
2.35E+15
374.58
0.49
2
5.00E+15
2.35E+15
374.58
3.2 EQE Measurement FIGURE 6 Capacitance Measurement Table.4. Capacitance Measurement Details
Area
Sample
Name
K
NA
(1/cm^3)
Mobility
(cm2/V S)
0.49
1
5.00E+15
2.35E+15
374.58
0.49
2
5.00E+15
2.35E+15
374.58 Table.4. Capacitance Measurement Details
Area
Sample
Name
K
NA
(1/cm^3)
Mobility
(cm2/V S)
0.49
1
5.00E+15
2.35E+15
374.58
0.49
2
5.00E+15
2.35E+15
374.58 Table.4. Capacitance Measurement Details 3.2 EQE Measurement 3.2 EQE Measurement 13 FIGURE 7 EQE Measurement FIGURE 7 EQE Measurement Fig 7 is EQE measurement of our device, We get 60 % efficiency. Because our devices are
not subjected to the ARC during the device making. Funding This
work
was
supported
by
the
Ministry
of
New
and
Renewable
Energy
(MNRE),
the
Government
of
India
(Order
no: 31/58/2013-2014/PVSE & 15-01-2015). This
work
was
supported
by
the
Ministry
of
New
and
Renewable
Energy
(MNRE),
the
Government
of
India
(Order
no: 31/58/2013-2014/PVSE & 15-01-2015). of G Aravindan acknowledges Human Resource Development Group, Council of
Scientific & Industrial Research for Direct Senior Research Fellowship, Government of
India (Sanction letter no/file no: 08/542(0010)2K19 EMR-I). Conflicts of interest/Competing interests The authors have no conflicts of interest to declare that are relevant to the content
of this article. 4 CONCLUSION The boron doped multi-crystalline silicon (mc-Si) ingot was grown using the directional
solidification process. Grown ingots were converted into bricks and then to wafers. The
investigation on the annealing temperature has been carried out. The mc-Si wafers were
subjected to four set of back contact annealing experiments. Annealing the device at 5830C for
5 sec gives better results. Typical Voc of the devices ~540-550mV. The best cell had a power
conversion efficiency of ~9 % with a typical acceptor doping density ~ 2.35 E+15 per cm3. Our devices are not subjected to the texturization, ARC and passivation. If we include all
process we get 17.6 % conversion efficiency [9]. Table.5. Expected Efficiency
Efficiency of our wafer (for FF=0.69)
9.23%
Expected Efficiency (If FF=0.80)
10.6%
Expected Efficiency with Passivation (4%)
11.01%
Expected Efficiency with ARC (24 %)
13.2%
Expected Efficiency with ARC and Passivation (55 %)
16.4%
Expected Efficiency with ARC, Passivation and Texturization (61 %)
17.1% Table.5. Expected Efficiency
Efficiency of our wafer (for FF=0.69)
9.23%
Expected Efficiency (If FF=0.80)
10.6%
Expected Efficiency with Passivation (4%)
11.01%
Expected Efficiency with ARC (24 %)
13.2%
Expected Efficiency with ARC and Passivation (55 %)
16.4%
Expected Efficiency with ARC, Passivation and Texturization (61 %)
17.1% Table.5. Expected Efficiency 14 Code availability 15 Authors' contributions Authors
Contribution
G. Aravindan
Conceptualization, Methodology, Formal analysis,
Investigation, Data Curation, Resources, Writing -
Original Draft, Writing - Review & Editing
S. Sanmugavel
Methodology, Formal analysis, Investigation
S. G. Nagarajan
Investigation, Validation
V. Kesavan
Formal analysis
M. Srinivasan
Visualization
P. Ramasamy
Supervision
Acknowledgments
The authors are thankful to K. L. Narasimhan and B. M. Arora, National Centre for
Photovoltaic Research and Education (NCPRE), IIT Bombay for useful discussion. NCPRE
PUMP program, IIT Bombay. G Aravindan acknowledges Human Resource Development
Group, Council of Scientific & Industrial Research for Direct Senior Research Fellowship,
Government of India (Sanction letter no/file no: 08/542(0010)2K19 EMR-I). Authors
Contribution
G. Aravindan
Conceptualization, Methodology, Formal analysis,
Investigation, Data Curation, Resources, Writing -
Original Draft, Writing - Review & Editing
S. Sanmugavel
Methodology, Formal analysis, Investigation
S. G. Nagarajan
Investigation, Validation
V. Kesavan
Formal analysis
M. Srinivasan
Visualization
P. Ramasamy
Supervision Acknowledgments The authors are thankful to K. L. Narasimhan and B. M. Arora, National Centre for
Photovoltaic Research and Education (NCPRE), IIT Bombay for useful discussion. NCPRE
PUMP program, IIT Bombay. G Aravindan acknowledges Human Resource Development
Group, Council of Scientific & Industrial Research for Direct Senior Research Fellowship,
Government of India (Sanction letter no/file no: 08/542(0010)2K19 EMR-I). The authors are thankful to K. L. Narasimhan and B. M. Arora, National Centre for
Photovoltaic Research and Education (NCPRE), IIT Bombay for useful discussion. NCPRE
PUMP program, IIT Bombay. G Aravindan acknowledges Human Resource Development
Group, Council of Scientific & Industrial Research for Direct Senior Research Fellowship,
Government of India (Sanction letter no/file no: 08/542(0010)2K19 EMR-I). 16 9. Crotty G et. Al. Front surface passivation of silicon solar cells with antireflection
coating. Journal of Applied Physics. 1987;61:3077. 5 REFERENCE 1. Lin KM, Lin HH, Dandage HK, Du YC. Pseudo colorization of electroluminescence
images
of
multi-crystalline
silicon solar cells for defect inspection. Modern Physics Letters B. 2019;33(14&15):
1940010. 1. Lin KM, Lin HH, Dandage HK, Du YC. Pseudo colorization of electroluminescence
images
of
multi-crystalline
silicon solar cells for defect inspection. Modern Physics Letters B. 2019;33(14&15):
1940010. 2. Yadav TS, Sharma AK, Kottantharayil A, Basu PK. Low-cost and low-temperature
chemical oxide passivation process for large area single crystalline silicon solar cells. Solar Energy, Solar Energy. 2018;169:270-276. 3. Cui
M,
Jin
C,
Zhuge
L,
Wu X. Optik. The impact of diffusion gettering on solar cell efficiency
and
light
induced
degradation
Authors.2019;181:129-133. 4. Chan C, Hamer P, Bourret-Sicotte G, Chen R, Ciesla A, Hallam B, Payne D, Bonilla
RS, Wenham S. Instability of Increased Contact Resistance in Silicon Solar Cells
Following Post-Firing Thermal Processes. Solar. 2017;1700129. 5. Peral A, Dastgheib-Shirazi A, Fano V, Jimeno JC, Hahn G, Canizo CD. Impact of
Extended Contact Cofiring on Multicrystalline Silicon Solar Cell Parameters. IEEE
Journal of Photovoltaics. 2017;7:91-96. 6. Chan CE, Payne DN, Hallam BJ, Abbott MD, Fung TH, Wenham AM, Tjahjono BS,
Wenham SR. Rapid Stabilization of High-Performance Multicrystalline P-type Silicon
PERC Cells. IEEE Journal of Photovoltaics, 2016;6,1473-1479. 7. Wu S, Wang W, Li L, Yu D, Huang L, Liu W, Wua X, Zhang F. Investigation of the
mechanism of the Ag/SiNx firing-through process of screen-printed silicon solar cells. RSC Advance. 2014;4: 24384-24388. 8. Peral A, Lelièvre JF, Recart F, Cañizo CD. Defect engineering during the contact co-
firing step in an industrial belt furnace. Phys. Status Solidi C, 2012;1–4. 17 18 Figures Figures 1a. Directional Solidi¦cation Furnace 1b. As-grown Multi-crystalline Silicon 1c. As-Cut Brick from the
grown ingot 1d. Multi-Crystalline silicon wafer Figure 1 1a. Directional Solidi¦cation Furnace 1b. As-grown Multi-crystalline Silicon 1c. As-Cut Brick from the
grown ingot 1d. Multi-Crystalline silicon wafer Figure 2
Lithography (a) Lithography setup (b) Patterned mc-Si wafer Figure 2 Lithography (a) Lithography setup (b) Patterned mc-Si wafer Lithography (a) Lithography setup (b) Patterned mc-Si wafer Figure 3
Front contact (a) mc-Si wafer after the Front side contact (b) Metal mask (c) mc-Si wafer after the Back
side contact Figure 3 Figure 3 Front contact (a) mc-Si wafer after the Front side contact (b) Metal mask (c) mc-Si wafer after the Back
side contact Figure 4 Dark IV curve of various annealing experiments. A, B, C, D, E, F and G are corresponding to 590¬0 C 5 min,
6000 C 5 min, 5900 C 5 min two times, 6000 C 5 min two times, 6100 C then 5750 C 5 min, 5830 C 5 sec
and 5940 C 5 sec. Dark IV curve of various annealing experiments. A, B, C, D, E, F and G are corresponding to 590¬0 C 5 min,
6000 C 5 min, 5900 C 5 min two times, 6000 C 5 min two times, 6100 C then 5750 C 5 min, 5830 C 5 sec
and 5940 C 5 sec. Figure 5
Light IV curve of various annealing experiments. A, B, C, D, E, F and G are corresponding to 590¬0 C 5 min,
6000 C 5 min, 5900 C 5 min two times, 6000 C 5 min two times, 6100 C then 5750 C 5 min, 5830 C 5 sec
and 5940 C 5 sec. Figure 5 Light IV curve of various annealing experiments. A, B, C, D, E, F and G are corresponding to 590¬0 C 5 min,
6000 C 5 min, 5900 C 5 min two times, 6000 C 5 min two times, 6100 C then 5750 C 5 min, 5830 C 5 sec
and 5940 C 5 sec. Light IV curve of various annealing experiments. A, B, C, D, E, F and G are corresponding to 590¬0 C 5 min,
6000 C 5 min, 5900 C 5 min two times, 6000 C 5 min two times, 6100 C then 5750 C 5 min, 5830 C 5 sec
and 5940 C 5 sec. Figure 6 Figure 6 Capacitance Measurement Capacitance Measurement Figure 7 EQE Measurement
|
https://openalex.org/W2902425386
|
http://humangeographies.org.ro/articles/122/a_122_2_ljakoska.pdf
|
English
| null |
The reproductive behaviour of the female population in the only Roma governed community in Europe
|
Human Geographies
| 2,018
|
cc-by
| 9,783
|
University of “Ss Cyril and Methodius”, Republic of Macedonia University of “Ss Cyril and Methodius”, Republic of Macedonia This paper puts a special accent on the Roma female reproductive population and its
behaviour concerning the formation and size of the family. A survey was conducted in the
area of Shuto Orizari, the only Roma governed community in Europe, on respondents from
the female reproductive population divided into three age groups. For the analysis of the
variance of the means of the three chosen groups were used the standard statistical tests and
the one-way ANOVA test was used for testing the eight hypotheses for the equality of the
means of the three independent specimens. A chi-squared test of independence between the
two variables was made on the whole sample. The research and the gained results about the
factors that determine the demographic behaviour of the Roma female reproductive
population are expected to nd a way to improve the overall situation and to use it in
creating demographic policies. Key Words: Roma female population, reproduction, children, demographic policies, Shuto
Orizari. Article Info: Received: June 26, 2018; Revised: October 25, 2018; Accepted: November 5, 2018;
Online: November 30, 2018. Article Info: Received: June 26, 2018; Revised: October 25, 2018; Accepted: November 5, 2018;
Online: November 30, 2018. Human Geographies – Journal of Studies and Research in Human Geography
Vol. 12, No. 2, November 2018 | www.humangeographies.org.ro
ISSN–print: 1843–6587 | ISSN–online: 2067–2284 Human Geographies – Journal of Studies and Research in Human Geography
Vol. 12, No. 2, November 2018 | www.humangeographies.org.ro
ISSN–print: 1843–6587 | ISSN–online: 2067–2284 Biljana Apostolovska Toshevska, Mirjanka Madjevikj,
Marija Ljakoska*, Petar Sokoloski University of “Ss Cyril and Methodius”, Republic of Macedonia Introduction In general, the Roma population is most often presented as a marginal group
facing many difculties regarding social status, emancipation and changes in
collective behaviour, which makes their integration in the modern societies even
harder and more stringent. It is mostly as a result of their education, economic
status, religion, but also because of their isolation and "ghettoisation" in which
* Corresponding author ©2018 Human Geographies; The authors
This work is licensed under a
Creative Commons Attribution 4.0 International License. DOI:1
8 122 2
0.5719/hgeo.201 . . p
g
Address: Faculty of Natural Sciences and Mathematics, Institute of Geography,
Arhimedova 3, 1000, Skopje, Republic of Macedonia. Phone: +38970862831 | Email: ljakoska.marija@yahoo.com Address: Faculty of Natural Sciences and Mathematics, Institute of Geography, Arhimedova 3, 1000, Skopje, Republic of Macedonia. Ph
38970862831 | E
il lj k
k
ij @
h Phone: +38970862831 | Email: ljakoska.marija@yahoo.com ©2018 Human Geographies; The authors ©2018 Human Geographies; The authors This work is licensed under a Creative Commons Attribution 4.0 International License. DOI:1
8 122
0.5719/hgeo.201 . Biljana Apostolovska Toshevska et al. 158 Figure 1. Location of the municipality Shuto Orizari in the Skopje region Figure 1. Location of the municipality Shuto Orizari in the Skopje region the customary laws in the community are the determinants of the individual’s
behaviour and decisions. The term is symbolically used even though, according
to its characteristics we cannot say that it is not a real ghetto or "(neo-) ghetto"
according to Marinaro (2017). The use of the term "ghettoisation" in the
concrete case has a double purpose. On the one hand, it aims to clarify a spatial
organisation in which there is a visible ethnic spatial segregation of the Roma
population by its will or without any additional alternative for economically
available housing areas. On the other hand, "ghettoisation" should be under-
stood as a spatial framework that is related to the situation and the behaviour of
the Roma population. "This, in turn, ensures social and spatial separation and
instils mutual avoidance behaviour" (Creţan and Powell, 2018), with the rest of
the non-Roma population. Hence, such conditions affect the decisions regarding
reproductive behaviour and the attention paid to designing the size of the
families. According to the Constitution of the Republic of Macedonia, Roma have an
accepted status of a national group in the country. Introduction By the 2002 population
census data, about 53,875 people in the Republic of Macedonia were recorded
as Roma nationality people or 2.66% of the total population in the country. From 1948 to 2002 their number had been continuously increasing, mostly
through natural growth. At the same time, the population increased more than
2.5 times. "It should be taken into consideration that the phenomenon of ethnic
mimicry, by which the Roma mainly want to get rid of their socially secluded
existence, signicantly contributes to the stance of attitude when declaring the
ethnicity of Roma from one population census to another" (Knežević, 2010),
which also points to the condition of political manipulation of the socially most
vulnerable category of citizens in the country. About 95% of the whole Roma population are living in cities (Stojmilov and
Apostolovska Toshevska, 2015), 43.6% of which live in Skopje. About 1/4 of the The reproductive behaviour of the female population 159 whole Roma population in the country lives in Shuto Orizari (gure 1) and "its
unique distinction is in the fact that it has been the only Roma governed
community in Europe" (Trbojević and Bogoevska, 2011), since 1996. According
to the 2002 population census, over 60% of the total population in Shuto Orizari
is Roma. Although the Government of the Republic of Macedonia has implemented a
number of projects to improve their economic and social status, and simulta-
neously a large number of Non-Governmental institutions operate with the
same goal, it must be emphasised that the desired results have not been fully
achieved. The Roma population still has a low level of education, which is an
additionally aggravating factor for the future employment and the improvement
of the social status. According to the Employment Service Agency of the
Republic of Macedonia at the end of 2016, 6,201 unemployed people from
Roma nationality were registered, or close to 6% of the total number of unem-
ployed people in the country. Over 1/3 of them were women. Roma people
occupy the lowest place in the labour market, and only 20% have regular
employment (Trbojević Bogoevska, 2011). The state-level data show that the
noted reproduction of the Roma is twice as higher than the state average. The
infant mortality rate is twice as higher than any other ethnic groups (Strategy
for Roma in the Republic of Macedonia, 2014-2020). Introduction A huge problem is the
presence of more forms of indirect discrimination in the healthcare department,
which is additionally reecting the reproductive behaviour and the ability to
create a family. This initial representation of the demographic characteristics and demo-
graphic behaviour of the Roma population is necessary in order to keep track of
our research paper. The research attempts to present the real state of the
behaviour of the female reproductive population in the municipality that
absorbs the largest share of the Roma population in the country. More precisely,
"for many of us who are studying contemporary topics, we have the opportunity
to try to create the appropriate data ourselves because, ofcial data do not
provide a complete and transparent picture of the social reality" (Cloke et al.,
2002). The conducted survey provides information on the stands of the Roma
population in terms of reproductive behaviour. However, despite the specics
regarding the reproductive behaviour of the Roma population, particular
scientic papers derived initially or that are related to the events occurring in
the municipality Shuto Orizari have not been recorded. Numerous researches and reports have been made about the situation of
Roma in Macedonia for the needs of different non-governmental organisations
and government policy makers, especially for the Decade of Roma Inclusion. This paper is an original source of knowledge about the attitudes of the Roma
female reproductive population, analysed in the inter-generational range of 30
years, in both, the cultural and social introverted environment, where it is
difcult to realise this type of research. At the same time, a chi-squared test of
the independence of variables was made on the whole sample in order to
evaluate the connection between education and reproductive behaviour, as well
as the type of sources of income with the number of children in the family. yp
y
The research conducted for the purpose of creating this paper is very
signicant because, despite the given ofcial data from the State Statistics, by Biljana Apostolovska Toshevska et al. 160 which the percentage share of the Roma population in the country is tiny, they
are still specic in a way because of the high birth rates and the importance they
give to the children of the family. Based on their attitudes, one can perceive which are the most signicant
difculties that hinder their faster progress and control their reproductive
behaviour and family planning. Introduction By dening such barriers, the directions and
elds where action should be taken and what approach should be used can be
recognized. The aim of this paper is to increase the sensibility of the local community and
the competent institutions for actual developments in the reproductive behav-
iour of this population and the series of accompanying consequences that come
as a result. The data in the paper derive from direct users of the measures and
solutions implemented by the government for building a more inclusive society. Therefore, this paper should cause a critical review of the vast extent of the
failures of the series of government programs and strategies for the social
development of the Roma population and their inclusion in society. The reproductive behaviour of the female population The survey was carried out by trained professionals by visiting Roma women
in this municipality, which secured the reliability of the data. The interviewed
population responded to a questionnaire prepared for this purpose, consisting
of 30 open and semi-closed type questions regarding their reproductive behav-
iour, opinions on the number of children, and family planning. The questions
included clarication of the primary data about the person, such as religion,
education, marital status, economic status, living conditions, in order to give
additional background to the other responses about the reproductive behaviour. The survey was conducted between April and May 2017 in the municipality
of Shuto Orizari (a municipality in the territorial scope of the city of Skopje),
which is the only independent Balkan municipality mainly inhabited by Roma
population, or, "the largest Gypsy community in general, (although it has its
competitor in Sliven, Bulgaria)" (Fraser, 1995), as an example of a segregated
living environment for the Roma. For this research, the expert opinion of
someone that is directly related to this issue was taken into account. The
standard statistical tests were used to analyse the variance of the means of the
three considered groups, the Microsoft Excel application and the SPSS statistical
package too in order to obtain the expected results. The one-way ANOVA test
was used to test the eight hypotheses for the equivalence of the means of the
three independent samples. Starting from the assumption that education and
economic status have an impact on the reproductive behaviour, a chi-squared
test of the independence of the whole sample has been made. From other data
sources relevant to the research of births and reproductive behaviour of the
population in the past, the publications of the State Statistical Ofce of the
Republic of Macedonia (SSORM), for vital statistics have been used. It contains
the yearly number of births by age and nationality of the mother and father in
the municipality of Shuto Orizari. Data source and research methodology The research regarding the female reproductive population in Shuto Orizari is
based on the use of the appropriate scientic-research methods. The basic
methodology used in the research starts with the ndings from the analytic
material from the survey and the data from secondary sources – statistical data,
researches done so far that are related to this issue and the experts’ opinion. A eld survey was conducted for this study. The survey included 50 women
in their reproductive age, accounting for 0.5% more than of the total reproduc-
tive population in Shuto Orizari, based on our own population estimates for
2016. Because the last population census in Macedonia was conducted in 2002,
the authors made their own estimates for the number of the population in the
municipality of Shuto Orizari as there is no ofcial statistical data for the
population number. Estimations show that in 2016, the number of Roma women
in the reproductive age in Shuto Orizari is 4,530. Given that this is a relatively homogeneous population in terms of demo-
graphic characteristics (criteria are met in terms of size, age, ethnicity, education,
social status, marriage, etc.), the given sample is large enough to be representa-
tive and satises the possibility of generalising the results obtained for the entire
statistical population. Namely, by conducting a survey of selected samples, the
aim is to obtain information about the basic population, taking into account that
the properties of the sample are as close as possible to the characteristics of the
target group, in this case of the Roma reproductive population in Shuto Orizari. A sample of the female reproductive population was surveyed, aged between
15 and 49, divided into three age groups: born in the period from 1972 to 1979
(with 14 respondents), women born in the period from 1980 to 1989 (with 24
respondents) and in the period from 1990 to 2002 (with 12 respondents). That
is, women who are at the end of their reproductive age, women who are at an
optimal reproductive age, and those who are at the beginning of the reproduc-
tive period and who have yet to achieve their reproductive role. 161 The reproductive behaviour of the female population European Roma population – characteristics and condition A large number of Roma migrated to Great Britain, France,
Italy, and Germany (Brown et al., 2014; Clough Marinaro, 2003; Maestri, 2014). y
y
g
The Roma population is the most vulnerable group in Europe, with values
above average, for all leading indicators of social exclusion such as "higher
infant mortality rates, shorter life expectancy, lower income per capita and a
higher unemployment rate" (European Commission, 2004). For example, if the
average life expectancy in the EU is 76 for men and 82 for women, the estimates
for the Roma population are 10 years less (European Commission, 2011). According to UN reports in only ve countries, the level of mortality among
Roma children is 2 to 6 times greater than in the rest of the population, indicat-
ing health differences and access to health care services. They are characterised
by high participation in the total birth rate in the countries in which they live. In
Croatia, mothers of Roma nationality have three or more children (Pavić, 2013). "In Serbia, the adolescent birth rate among the Roma population is 158, more
than six times the national average of 23.9 and higher than the rate in many of
the least developed countries" (UNFPA, 2013). p
All countries experience similar cases, which in corroboration with the age of
the mother when giving birth, undoubtedly leads to deeper problems for the
future generations and society as a whole. More precisely, as Gabel (2009) noted,
in Bulgaria, which is basically a depiction of the situation for most of the Roma
population in Europe, "Roma mothers are younger, less educated, poorer and
tend to have more children than ethnic Bulgarian women". In Bulgaria, "more
than 50% of Roma adolescent girls gave birth to a child before turning 18"
(UNFPA, 2013). In Hungary, "the average age of a Roma woman to have her
rst child is 20 years. Three in ten Roma women become mothers before they
reach the age of 18 and around two-thirds have their rst child at the age of 20
at the latest" (Janky, 2006). "The birth rate among Roma women is still about
twice as high as that of the overall Slovak population" (Vašečka et al., 2003). "In
Albania, the average age of Roma mothers at the birth of their rst child was
16.9 years" (UNFPA, 2013). European Roma population – characteristics and condition Roma people are a transnational ethnic group without a home state and are
largely present in European countries (Novak, 2004). According to Di Giovanni
(2007), "they are people without land and without homeland". "Gypsies are often
portrayed as a closed, ethnic group that has successfully resisted assimilation
and cultural change. Their core elements are their itinerant way of life and
the ensuing cultural norms and traditional occupations, which would set them
clearly apart from the rest of society" (Lucassen, Willems, 2003). They are
supposed to have an Indo-European origin, and it is scientically accepted that
they came to Europe from India about 1,000 years ago and settled in Europe
th
around the 14 century (Fraser, 1995). There are difculties in making precise estimates of the number of the Roma
population in Europe. "Some of the factors complicating identication include
the under-sampling of Roma residential areas, difculties locating unregistered
Roma and problems with self-reporting. The Roma may choose not to identify
because of fear of discrimination, among other reasons" (Gabel, 2009). Sometimes there are changes in their declaration based on their place of origin,
due to certain benets that they can derive, for example, in Romania. 162 Biljana Apostolovska Toshevska et al. According to Creţan and Turnock (2008), "opportunistic Roma may nd it
convenient to change their identity in order to gain advantage, e.g. in 2001
some Roma in Transylvania claimed they were Hungarian in order to benet
under a short-lived project by Hungary’s Fidesz government to give Hungarian
passports to Transylvanians on a double citizenship basis: in this way they could
gain entry to EU states ahead of Romania’s own accession in 2007." g
y
It is estimated that this most signicant minority in Europe adds up to
between 10 and 12 million (European Commission, 2011). Most of them live in
the countries of Central and Eastern Europe, as well as in the countries of
Southeast Europe (European Commission, 2011; Open Society Institute, 2007). According to the estimates for 2010, around 6,172,800 Roma or 1.73% of the
total population (from the average) was recorded in the European Union. Most
of them are located in Bulgaria, Slovakia, Hungary, and Romania. Outside the
EU countries, the largest percentage share of the total population in the country
is recorded in Serbia, Macedonia, Albania and Montenegro (European
Commission, 2011). The reproductive behaviour of the female population All authors who deal with this issue, identify education as a way to improve
the situation caused by high fertility, births occurring in the case of minors, and
the problematic inclusion of Roma women in the labour market precisely
because of inadequate education and qualications. In Slovakia, "only six out of
100 Roma women had an education higher than elementary level. As the results
from the last two censuses showed, the situation for Roma did not signicantly
improve in the last decade" (Sprocha and Bleha, 2017). In Croatia, the high
birth rate among Roma population is also correlated with the unfavourable
educational and economic structure of the families (Pavić, 2013). Education is more than necessary because the Roma population is young and
constitutes a large part of the workforce in Europe. In EU countries, 35.7% of
the Roma population is under the age of 15, compared to 15.7% of the total
European population, and the average age among Roma is 25 years, compared
to 40 years in the EU (European Commission, 2011). Investing in education will
enable employment and social inclusion in the European society. p
y
p
y
The biggest problem is their poverty, "the unemployment that is the result of
stereotypes about the Roma, their low level of education, and social exclusion"
(Josipovič and Repolusk, 2003). In many cases, the impression is that much
more is being written and planned than realized, which by itself requires the
need to reassess and deepen the analysis, because "the Roma are a specic
population that shows a typical image of low aspiration and rapid adaptation
abilities, but in order to become economically independent citizens, the pros-
pects for success can only have the measures that can be incorporated consis-
tently in the whole Roma life, not the measures that do not consider the urgent
needs, the culture and the tradition of the Roma" (Jaksić and Basić, 2005: 9). Another problem they face is the burden of the stereotypical behaviour from the
rest of the population in regards to their morals and manners. Hence, despite
the intention to include Roma in European societies, unfortunately, we can still
talk about stigmatised population, about "antiziganism" (Cambini and Fabeni,
2017), "romaphobia" (van Baar, 2011), Europe’s perennial "outsiders" (Powell
and Lever, 2015). The reproductive behaviour of the female population The academics still focus on the current events of their
marginalization, segregation and ghettoisation, on (neo-)ghetto, but also on a
series of xenophobic attitudes of certain states towards the Roma (Sigona, 2003;
Clough Marinaro, 2003, 2015, 2017; Filčák and Steger, 2014; O'Nions, 2014;
van Baar, 2012). In that case, it is entirely expected that they will lean and turn
to the local community "among their own". They will become even more isolated
which will affect all individual characteristics, including fertility behaviour
because an individual's fertility decisions are highly dependent on the fertility
behaviour, norms and values of other members of the local community (Kohler,
1997; 2001). European Roma population – characteristics and condition "For the great majority of young Roma women,
labour market integration is beyond hope and, consequently, they place greater
emphasis on status attainment through childbearing, which in turn further
reduces their chances of ever integrating in the future" (Janky, 2006). 163 The reproductive behaviour of the female population Results When selecting the concrete hypotheses that were going to be the subject of this
research, the starting point was set on the existing demographic processes
characteristic of the Roma population (Madjevikj, 2000 & 2004; Madjevikj et al.,
2016). The image of a population that early joins the reproductive ows, which Biljana Apostolovska Toshevska et al. 164 Table 1. Percentages, arithmetic means, and standard deviations of the data. I
Group one
Group two
Group three
p-value
μi,1
SDi,1
μi,2
SDi,2
μi,3
SDi,3
1
15.928
1.9
17.4545
1.654
17.182
2.4
0.089
2
2.93
1.14
2.58
1.06
2
1.13
0.125
3
23.08%
0.4385
16.7%
0.3807
33.33%
0.4924
0.54
4
70%
0.233
73%
0.2095
90%
0.0909
0.47
5
2.64
1.07
2.46
0.93
2.58
0.669
0.82
6
0.9
0.7379
0.2105
0.5353
0.0769
0.2774
0.0015
7
92.86%
0.0714
100%
0
83%
0.1515
0.14
8
93%
0.2673
96%
0.2041
83%
0.3892
0.438
Source: Authors calculations using the results of the conducted survey Table 1. Percentages, arithmetic means, and standard deviations of the data. I
Group one
Group two
Group three
p-valu le 1. Percentages, arithmetic means, and standard deviations of the data. G
G
t
G
th nurtures the attitude towards families with many children (Jovanović, 1998 nurtures the attitude towards families with many children (Jovanović, 1998;
Dragović, 2009), which is mostly the socially marginalised group without proper
education, are the essential conceptual basis in dening the research hypothesis. The statistical research was conducted using standard assumptions. The hypoth-
esis tested was whether there is any difference between the three age groups
regarding the following questions: The statistical research was conducted using standard assumptions. The hypoth-
esis tested was whether there is any difference between the three age groups
regarding the following questions: –
An age when the rst child was born; –
An age when the rst child was born; –
Number of children in the family; –
Whether the respondent uses contraception (percentage share of those
using); –
Visits to the gynaecologist during pregnancy (percentage share for all those
who had visited a gynaecologist on a regular or part-time basis. Results In this
regard, only the respondents who answered the question were taken into
consideration); –
How many children should a family have; –
Number of intentional abortions; –
Who takes care of the children (percentage share of those who think that
both parents should participate equally); –
Who takes care of the children (percentage share of those who think that
both parents should participate equally); –
Who should contribute to the family budget (percentage shares of those who
think that both parents should contribute equally). The results are summed up in table 1. It was worked with a signicance level of 5%. The following hypotheses were
tested, Hi,0: μi,1 = μi,2 = μi,3, for i = 1,2,…,8. Where μi, j is the mean value for the i-th hypothesis in the j-th age group (j
receives values 1, 2 or 3). If we examine percentage shares, check the connec-
tion between the gained proportions. Where μi, j is the mean value for the i-th hypothesis in the j-th age group (j
receives values 1, 2 or 3). If we examine percentage shares, check the connec-
tion between the gained proportions. Regarding all issues, except for the number of intentional abortions, there
was no signicant difference, i.e. the test was not signicant. In other words,
although there is some difference among the age groups regarding all these
questions, there is no signicant statistical difference regarding the issues
previously mentioned. In order to deepen the research, the sample was ana-
lysed as a unique entity. Through the chi-squared test of independence, it was
examined whether in the contingency table the distribution of one variable The reproductive behaviour of the female population 165 conditionally depends on the distribution of another variable. With the null
hypothesis, we claim that the variables are independent, that is, the distribution
of one variable does not depend on the spread over the other variable. The variable of education has been tested with: the number of children, the
use of contraception, the visits to a gynaecologist, the visits to a gynaecologist
during pregnancy, an unplanned or intentional pregnancy. The variable for the
source of income has been tested with the number of children. Results Among the
different variables of the whole sample, the following results emerged: –
There is a statistically signicant link between education and the number of
births with a coefcient of contingency of 0.647, (the chi-square (36.5) is
higher than the limit value (24.996) for DF = 15 and the level of signicance
of 0.05). –
The frequency of visiting a gynaecologist depends on education with a
coefcient of contingency of 0.66, (the chi-square (38.9) is higher than the
limit value (21.026) for DF = 12 and the level of signicance of 0.05). –
There is a statistically signicant link between the education of the respon-
dent and the habit of visiting a gynaecologist during pregnancy (coefcient
of contingency 0.55). The chi-square (22.3) is higher than the limit value
(16.919) for DF = 9 and the level of signicance of 0.05. –
There is a connection between the level of education of the respondent and
the use of contraception (coefcient of contingency 0.37). The chi-square
(7.95) is higher than the limit value (7.815) for DF = 3 and the level of
signicance of 0.05. –
There is no link between the level of education of the respondent and the
type of pregnancy (unplanned or intentional). The chi-square (5.98) is lower
than the limit value (12.592) for DF = 6 and the level of signicance of 0.05. –
There is no link between the level of education of the respondent and the
type of pregnancy (unplanned or intentional). The chi-square (5.98) is lower
than the limit value (12.592) for DF = 6 and the level of signicance of 0.05. –
The sources of income are not an obstacle for a higher number of children. The chi-square (11.56) is lower than the limit value (31.410) for DF = 20 and
the level of signicance of 0.05. Discussion It is evident that the Roma population has a different approach to the reproduc-
tive behaviour, one utterly different from the rest of the non-Roma population
that surrounds them. Their reproductive strategy is "at the core of their social
organisation and their cultural expression. This cultural emphasis on reproduc-
tion has to be seen in the context of the historical discrimination and exclusion
suffered by most Romani groups." (Gamella, 2018). Despite the expected
differences in reproductive behaviour among the different groups of respon-
dents, it is more than evident that the expected results were not obtained. The
difference between the oldest and the youngest is even over 30 years, so it is
evident that the changes are slow and hardly noticeable. Out of the responders of the oldest age group (who are getting close to the
end of their reproductive age) 2/3 of the women gave birth to their rst child
between the age of 14 and 16; among women born from 1980 to 1989 the births
at this age were off to 50%, and 25% of the women gave birth at the age of 19. In the youngest group, only 25% of the women gave birth between the age of 14 Biljana Apostolovska Toshevska et al. 166 and 16, and 1/3 at the age of 18. No matter how small of a step forward we
might see (which statistically speaking, is not so signicant), from a demographic
point of view, this is an important indicator of the small positive changes in the
reproductive behaviour. This indicator is critical because "the age of women at
their rst birth is a key element in their reproductive history. It affects the total
number of births that a woman might have, and it inuences the size, composi-
tion and the level of completed fertility of the population." (Gamella, 2018). However, the general conclusion is that Roma woman still gives birth early in
life, for the most part, at an age not suitable and possibly harmful to their
physical and mental health, which in terms of social vulnerability leads towards
unhealthy life and a range of personal and social problems. This is largely a
result of their upbringing because all respondents conrmed the perception of
marriage and giving birth at a young age, as for both, husband and wife. The
oldest average age as an ideal age for getting married is 25. Discussion Juvenile marriages
are prevalent among the Roma population, but providing concrete data is
difcult because they are not recorded (Country Reports on Human Rights
Practices – Macedonia, 2008). Under the circumstances, "when other factors are expected to work in
favour, the percentage of marriages that are left without children is the smallest
if the girl gets married between the age of 18 and 23" (Breznik, 1967). At the
same time, those are the years that are considered to be the most suitable age for
a woman to give birth, according to Lorimer (Wertheimer Baletic, 1973). Also,
despite their young age when they gave birth to their rst child, the statements
of 99% of the respondents is that it would have been better if they had given
birth later, which indicates the connection with the inuence and pressure of the
environment and the collective local awareness of specic unwritten rules of
behaviour which women must follow so to avoid judgement. Hence, the gender
role in the family is also established as a factor for the reproductive behaviour,
and in this context, the demographic image of the Roma population is not
gender-neutral. The traditional cultural habits limit the reproductive rights of
Roma women. More precisely, even in the 21st century, in most cases, the Roma
woman does not fully manage her reproductive behaviour plans, which at the
very least can dene her as a victim of community perceptions, patriarchal
attitudes, an underestimated attitude towards women and her marginalised role
in making family decisions. Overcoming this condition is even more difcult
because of the joint living in large, multiple generational families where the
inuence and the role of the elderly, in this case, the parents, is indisputable. According to the 2002 census data, in Suto Orizari, 3,908 households out of
5,102 households consisted of one family, and 867 households consisted of two
or more families (SSORM, 2004). Multi-children families are inevitable in the presence of early births and a
more extended reproductive period ahead, in the absence of sufcient attention
to contraception when contraception is still a taboo. In actuality, the number of
births has been lower than the ideal number of children, that is, the realised
fertility is lower than the ideal number of children (Goldstein et al., 2003). Discussion When
it comes to the Roma population the situation is vice versa, which indicates a
lower ability to regulate reproduction and a little knowledge of modern contra-
ception (Packer, 2003; Ringold et al., 2005). To illustrate, we would say that the The reproductive behaviour of the female population 167 use of modern contraception among Roma women in Macedonia between 15 to
49 years is only 7% (Ministry of Education and Science, Ministry of Labor and
Social Policy and Ministry of Health, 2011). The most popular method is the
withdrawal, which is used by one in three married Roma women in Macedonia,
and the next most popular method is the male condom. The use of contracep-
tion during the sexual intercourse is decided mainly by the man and his percep-
tion of his role in reproduction. "Reecting the expectations that Roma women
will be obedient and submissive, rst as girls, and later as wives and mothers,
Roma men are expected to prove their masculinity and perform their role as
husbands by limiting the freedom of movement of women, control over their
bodies, refusal to use contraception, etc." (Roma Early Childhood Inclusion -
Macedonian Report, 2012). During 2012, 26% of the Roma women did not use contraception, which
resulted in a high percentage of participation in the total number of abortions in
Macedonia of 34%, (as opposed to a 10% share of the Macedonians) (Strategy
for Roma in the Republic of Macedonia, 2014 – 2020). The inappropriate
protection against pregnancy is reected in the number of children in the
family. Therefore, statistics indicate that in the municipality of Shuto Orizari, the
average number of members in a household is more than 4, and is higher than
the national average. Among all age groups, the respondents still consider that
the family should have more than two children, which is more than the critical
value for simple reproduction. More than one-third of the children among the respondents are born in
illegitimate unions, and some of them are born in families with more children. Living in illegitimate unions is most characteristic for the middle and youngest
age group. Discussion Compared to their responses about the importance of the factors
that should determine the number of children in the family, the responses
indicate an awareness of the importance of the parents' nancial security and
the cost of taking care of the children, but in practice it is otherwise as a result of
accepting the traditional norms for the size of the family. p
g
y
The younger group of respondents compared with the oldest are accepting
some lower norms when it comes to the size of the family, but this conclusion
should be accompanied by the knowledge that some of these respondents are
still in their optimal reproductive period and it is likely that they can give birth
to more children. At the same time, this group of people undertakes specic
measures to control pregnancy by the increased use of contraceptive methods
(one-third of the respondents in the youngest group reported using contracep-
tion) and therefore the number of intentional abortions decreases. At the same time, this group of respondents compared to the other two
groups shows greater self-awareness for the importance of caring for their
reproductive health and care for the offspring, although they are far from the
predicted standards for tracking and controlling of pregnancy by a gynaecolo-
gist with more regular gynaecological examinations. Among the surveyed
women in the elderly groups, a smaller percentage of visits to a gynaecologist
during pregnancy and less care for contraception were noted. The health care system has to be adjusted for and to move closer to these
women. In this context, we should also refer to the research of the HERA
(NGO) for assessing the community for health care during pregnancy among Biljana Apostolovska Toshevska et al. 168 Roma women in Shuto Orizari conducted in the period from 2013 to 2015
which showed that the program for active protection of mothers and children
are not suitable for pregnant women, nor do they reach the nal users, which is
conrmed by the researches of some issues. Their observations point out that
the practice of Roma women to use health care during their pregnancies
increased by 0.2%, while the cooperation with the patronage service with the
mother and gynaecologists, the communication of the healthcare staff with the
Roma women in the ofce of the gynaecologist decreased. Discussion We have to note that for a signicant period of time there was no gynaecolo-
gist in Shuto Orizari, and the current solution to bring gynaecologists from
Albania who do not speak Macedonian nor Roma language is not a proper
solution. This way, the communication between the women and the doctor is
done in the presence of the medical nurse, and they have to receive recommen-
dations and advice from the doctor in the presence of a third person in order to
be able to communicate. This violates their intimacy and the need of a proper
doctor-patient communication, due to the nature of the examination, (the need
for information about the type and way of contraception, unplanned pregnancy)
which is of a sensitive and intimate nature, especially in closed and relatively
small communities like this one, where such information can cause discomfort in
the social environment. Based on the answers about who takes care of the children, the respondents,
in the most signicant percentage, take care of the children together. However,
observed in percentage share, it is obvious the difference in the youngest group
of respondents where this percentage is lower, despite the expectations that in
the youngest group we will receive answers that are characteristic for a younger
and more emancipated woman. They have similar attitudes about who should
contribute to the family budget. During the research, efforts were made to
include women with different levels of education in order to examine whether
education affects the reproductive behaviour of the analysed population of the
whole sample through a chi-squared test. According to the obtained indicators,
education has a statistically signicant inuence on the number of children in
the family, the frequency of visiting the gynaecologist in general and during
pregnancy in particular, and the use of contraception. Unfortunately, education
has no statistically signicant effect on the type of pregnancy (unplanned or
intentional). Such observations were imposed as a necessity given the low level of educa-
tion of the Roma population in general. However, it is a frightening fact that
even in the 21st century, the female, Roma population is still facing difculties
being involved in the educational system and is very slowly changes its status
regarding acquired education. The female Roma population is less educated
compared to female members of other nationalities in the country and is mainly
without any education or has received only an elementary education. Conclusion The changes in the Roma fertile-aged population that occurred in terms of
reproductive behaviour have been happening at a slow pace and are barely
noticeable. Studies have suggested that the hypothesis set statistically cannot be
fully veried despite the expectation that signicant positive changes in the
reproductive behaviour will be registered in the youngest respondent group,
except for the number of intentional abortions. The chi-squared test of inde-
pendence has shown that education is statistically signicant for reproductive
behaviour, except for the type of pregnancy. The type of sources of income has
no statistical signicance for the number of children in the family. In a broader context, the social moment is signicant, but it is imperative to
invest in the education of the Roma population. Specically, the results of the
survey are indicative and point to the need for increased awareness of the need
for education, family planning, healthcare for future mothers, as well as preg-
nant women. Education, which changes the views on several life segments, is
also a visa for the improvement of the social status. Along with education, (at
least the compulsory secondary education), essential conditions should be
created for their inclusion in the labour market and the employment of these
women population, in order to increase their self-esteem and social status, which
will indirectly inuence its role in setting up the frames of its reproductive
behaviour. At the same time, in the eld of healthcare, it is necessary to promote
a modern type of contraception that will be available to low-income people free
of charge (their number in Shuto Orizari is at an enormously high level), as well
as to make efforts to have at least one modern contraceptive item on the positive
drugs list. These measures should be followed by a certain number of subventions for
opening gynaecological clinics in the area of Shuto Orizari and opening educa-
tional stations for family planning in the Roma communities, which will also
develop a special program for educating the teenage population and reducing
pregnancy and abortions among the young population. Of course, in the efforts
to improve the whole situation, the education of the male population should
also be actively taken into consideration. y
The implementation of improving measures for reproductive behaviour are
important activities that are or should be managed by the state, but the role of
the local self-government is no less critical. Discussion Because of the implementation of compulsory secondary education (since
2008), the younger groups of respondents have completed secondary education. It is interesting that, to some extent, the traditional views about women's
virginity limit educational opportunities. Many Roma see the unmarried virgin
girl as a risk to the family, so they often do not allow them to continue their
education (Roma Early Childhood Inclusion - Macedonian Report, 2012). The reproductive behaviour of the female population 169 Photos 1 - 4. Living conditions of the Roma population in Shuto Orizari Photos 1 - 4. Living conditions of the Roma population in Shuto Orizari The lack of adequate documentation, necessary for inclusion in the educa-
tional process, the discrimination in the education system, the unsuitable
educational policies and programs, etc., have their inuence. An example of an
educational center with a specially designed program is Dendo-Vas - Center for
Educational Support, is a detailed educational program supported by the OFR. It provides additional education to Roma children (kindergarten, preschool
program, additional education for the children enrolled in primary schools,
family education) and is indicated as an alternative solution for the education of
Roma children. The level of education can contribute to having a better social status, reduc-
tion of teenage births, overcoming general beliefs of the environment and
observing and copying collective behaviour, even when it is inappropriate for
the individual and the society. At the same time, many of the respondents are
beneciaries of state benet, unemployed, or low paid workers and are barely
surviving, which contributes to women's insecurity, makes emancipation dif-
cult, and reduces their opportunity to impose their will regarding marriage,
when and how many children they should have to, because the importance of
the social and economic status of women and their fertility purpose cannot be
avoided. According to the last correlation, the two variables, that is, the type of
sources of income (salaries and pensions, pensions and social assistance, wages,
other sources of income) and the number of children are not related to one
another. More precisely, almost 50% of the respondents are beneciaries of
social assistance, out of which seventeen, besides social assistance, also receive a
pension (they mostly live in extended families), while six of the respondents live Biljana Apostolovska Toshevska et al. 170 only on the social assistance (photos 1-4). Discussion Recently, with the Government's policy
of promoting birth and subsidising the birth of a third child, signicant is the
number of Roma families that are beneciaries of such privileges. only on the social assistance (photos 1-4). Recently, with the Government's policy
of promoting birth and subsidising the birth of a third child, signicant is the
number of Roma families that are beneciaries of such privileges. Conclusion It can bring the measures and
solutions closer to the local population, depending on the trust it has indicated. Greater success can be expected if the activities of the state institutions are in
coordination with the activities of the non-governmental sector. The future
directions of taking action should consider the reproductive behaviour patterns
of the population. Based on this observation, essential priorities should be
determined that need to be fullled in order to observe positive changes. An
inclusive public policy that contains a set of measures targeted at the individual The reproductive behaviour of the female population 171 should respect individuality, distinctiveness and diversity. In no case should be
required simple stereotypical modelling of Roma in the model's design by the
authorities. The visible separation between the national agenda and the situa-
tion on the eld unequivocally indicates to inadequate approach in the
implementation of the changes. An integrative approach in the intention of
making changes in the sphere of marriage, partnership, and parenting and in
the processes of increasing the individuality of men and women is more than
necessary (Greene and Biddlecom, 2000). It is primarily necessary to overcome the situation of the "administrative
invisibility" of some Roma citizens. The lack of proper documentation disables
access to educational, social and health care system. The modication of the
strict clauses of the patriarchal community and the way of upbringing is more
than necessary. The education of parents for the awareness and acceptance of
the need to involve their children in the educational process is one part of the
movement in the mechanism for behaviour transformation. It is the core of the
intention of creating a more inclusive society. The activities should start much
earlier, in the early stages of life and development of the child in the Roma
family by changing the inherited model for the upbringing of children. It
should include appropriate education and upbringing in abandoning the
prejudice about the superiority or inferiority of the sexes, the stereotypes about
the role of the husband and wife in the family, the way of mutual respect and
the importance of family planning. p
y p
g
In our opinion, this can be achieved, especially with young married couples
living in the 21st century, who will have the desire to redirect their own life and
the life of their children in a better direction. Conclusion "Gender differences in terms of
reproductive behaviour are conditioned by the different behaviour of the sexes
within society, while on the other hand, they point on their different positions
which in some way inuence some other relevant demographic behaviours in
certain phases in the cycle of life" (Šobot, 2009). It is more than necessary to
note that the original researches such as this one should be more frequent in
order to put the basis for the implementation of measures to improve the
situation. At the same time, this research points to a dilemma that should
represent a debate topic in the academic and scientic community in Macedonia
and it refers to the (non)benets of such political, spatial and social closure of
the Roma population and how much it affects the reproductive attitudes, the
pace of integration and changing the views in a positive direction.Comparative
research is needed parallel to the researches on the reproductive behaviour of
the Roma woman in the ethnically and culturally mixed spatial units in the
country and abroad, which would contribute to dening the procedures for
overcoming conservative approaches to family planning and strengthening the
role of women in the family and in making marriage decisions. References Breznik, D., (1967), "Sterility of rst marriages", Population, no. 1, p. 41-50. Brown, P., Martin, P. and Scullion, L., (2014), "Migrant Roma in the United
Kingdom and the need to estimate population size", People, Place and Policy,
vol. 8, no. 1, viewed 19 March 2017, https://goo.gl/NdpE94. Cloke, P. and Cook, I. (2002) (eds.), Practicing Human Geography, Sage
Publications. Clough Marinaro, I. (2003), "Integration or marginalization? The failures of
social policy for the Roma in Europe", Modern Italy, vol. 8, no. 2, p. 203–18. Clough Marinaro, I., (2015), "The rise of Italy's neo-ghettos", Journal of Urban
History, vol. 41, no. 3, p. 368–87. Clough Marinaro, I., (2017), "The informal faces of the (neo-)ghetto: state
connement, formalization and multidimensional informalities in Italy's Roma
camps", International Sociology, vol. 32, no. 4, p. 545–62. Creţan, R. and Powell, R. (2018), "The Power of Group Stigmatization: Wealthy
Roma, Urban Space and Strategies of Defence in Post-socialist Romania",
International Journal of Urban and Regional Research, vol. 42, no. 3, p. 423-441. Creţan, R. and Turnock, D., (2008), "Romania's Roma Population: From
Marginality to Social Integration", Scottish Geographical Journal, vol. 124, no. 4,
viewed 5 March 2017, https://goo.gl/bJ96ru Di Giovanni, E. (2007), "Childhood in a roma/gypsy camp in south-Italy: an
anthropological perspective", International journal about Parents in Education, vol. 1, no. 0, p. 245-251. Dragović, V.A., (2009), "Low fertility, policies and quality of life in the Republic
of Macedonia", Review of Social Policy, vol. 1, p. 133-146. Dragović, V.A. (2009), "Some factors of lowering fertility in the Republic of
Macedonia", IUSSP 26th International Population Conference, 27 September
- 2 October, Palais des Congrès, Marrakech, Morocco. Eminova, E., Janeva, N. and Petroska-Beška, V. (2012), Roma Early Childhood
Inclusion - Macedonian Report, Open Society Foundations, UNICEF, Roma
educational fund, viewed 1 April 2017, https://goo.gl/RZowvF European Commission, (2011), Improving the status of Roma: a social and economic
imperative for the Union and its member states, Brussels. European Commission, (2004), The situation of Roma in an enlarged European
Union, Brussels. Filčák, R. and Steger, T. (2014), "Ghettos in Slovakia: the environmental exclu-
sion of the Roma minority", Analyse and Kritik, vol. 36, no. 2, p. 229–50. Fraser, A. (1995), The Gypsies, Blackwell Publishing Ltd., Oxford, United
Kingdom. Gabel, S.G. (2009), "The growing divide: the marginalization of young Roma
children in Bulgaria", International journal of social welfare, vol. 18, p. 65-75. Gamella, J.F. Acknowledgment The authors express their gratitude to Erhan Fejzof, B.Sc. in geography,
employee of the municipality of Suto Orizari, and also to Dr. Tase Cvetanovski,
Specialist in gynaecology for their expert opinion. Biljana Apostolovska Toshevska et al. 172 References Metamorfoza, Skopje. K
ž
ić
A
(2010)
R
(G p i ) i
B l
d
Eth
d
phi
St di Metamorfoza, Skopje. Knežević, A. (2010), Roma (Gypsies) in Belgrade - Ethnodemographic Studi Knežević, A. (2010), Roma (Gypsies) in Belgrade - Ethnodemographic Studies,
University of Belgrade, Faculty of Geography, Belgrade. Knežević, A. (2010), Roma (Gypsies) in Belgrade Ethnodemographic Studi
University of Belgrade, Faculty of Geography, Belgrade. Kohler, H.P. (1997), "Learning in Social Networks and Contraceptive Choice",
Demography, vol. 34, p. 369–383. Kohler, H.P. (2001), Fertility and Social Interactions: An Economic Perspective, Oxford
University Press, Oxford. y
Lucassen, L. and Willems, W. (2003), "The weakness of well-ordered societie Lucassen, L. and Willems, W. (2003), "The weakness of well-ordered societies. Gypsies in Western Europe, the Ottoman Empire and India 1400-1914",
R
i
l 26
3
283 313 Lucassen, L. and Willems, W. (2003), The weakness of well-ordered societies. Gypsies in Western Europe, the Ottoman Empire and India 1400-1914",
Review, vol. 26, no. 3, p. 283-313. Madjevikj, M. (2000), "Demogeographic analyses of the population natural
change in the Republic of Macedonia", PhD Thesis, "Ss. Cyril and Methodius"
University - Skopje, Faculty of Natural Sciences and Mathematics, Institute of
geography, Republic of Macedonia. Madjevikj, M. (2004), "The birth rate of the population in the Republic of
Macedonia", Geographical reviews, no. 38/39, p. 75-88. Madjevikj, M., Apostolovska Toshevska, B. and Ljakoska, M. (2016), "Regional
differences in the population natural increase in the Republic of Macedonia",
Journal of the Geographical Institute "Jovan Cvijić", SASA, vol. 66, no. 3, p. 417-
431. Maestri, G. (2014), "The economic crisis as opportunity: how austerity generates
new strategies and solidarities for negotiating Roma access to housing in
Rome", City, vol. 18, no. 6, p. 808–23. y
p
Ministry of Education and Science, Ministry of Labour and Social Policy and
Ministry of Health (2011), Multiple Indicator Cluster Survey, Skopje. y
p
y
pj
UNICEF, 2018, Surveys, viewed 5 January 2018, https://goo.gl/S3DYWi Ministry of Labour and Social Policy - Republic of Macedonia (2014), Strategy for
Roma in the Republic of Macedonia 2014 – 2020, Skopje, Republic of Macedonia. Novak, J. (2004), "The Roma community and international institutions: only
relative success in the protection of human and minority rights", Migration and
ethnic themes, vol. 20, no. 4, p. 403-432. O'Nions, H. (2014), "Some Europeans are more equal than others", People, Place
and Policy, vol. 8, no. 1, viewed 25 April 2017, https://goo.gl/TQq3DK. References (2018), "Marriage, Gender and Transnational Migrations in
Fertility Transitions of Romanian Roma Women. An Ethnographic Case
Study", Intersections. East European Journal of Society and Politics, vol. 4, no. 2, p. 57-85. Goldstein, J.R., Lutz, W. and Testa, M.R. (2003), "The emergence of sub-
replacement family size ideals in Europe", Population Research and Policy Review, The reproductive behaviour of the female population 173 vol. 22, p. 479–496. Greene, E.M. and Biddlecom, E.A. (2000), "Absent and Problematic Men:
Demographic Accounts of Male Reproductive Roles", Population and Development Review, vol. 26, no. 1, p. 81–115. HERA, 2018, Campaigns, viewed 5 March 2017, https://goo.gl/btMEE9. Janky, B. (2006), "The Social Position and Fertility of Roma Women", in I. Nagy, Development Review, vol. 26, no. 1, p. 81–115. HERA, 2018, Campaigns, viewed 5 March 2017, https://goo.gl/btMEE9. ky, B. (2006), "The Social Position and Fertility of Roma Women", in I. Nagy, M. Pongrácz and I.G. Tóth (eds.), Changing Roles: Report on the Situation of
Women and Men in Hungary 2005, TÁRKI Social Research Institute, Budapest. Josipovic, D. and Repolusk, P. (2003), "Demographic Characteristics of the M. Pongrácz and I.G. Tóth (eds.), Changing Roles: Report on the Situation of
Women and Men in Hungary 2005, TÁRKI Social Research Institute, Budapest. Josipovic, D. and Repolusk, P. (2003), "Demographic Characteristics of the
Romany in Prekmurje", ActaGeograpca Slovenica, vol. 43, no. 1, p. 127-147. Josipovic, D. and Repolusk, P. (2003), Demographic Characteristics of the
Romany in Prekmurje", ActaGeograpca Slovenica, vol. 43, no. 1, p. 127-147. Jaksić B and Basić G (2005) The art of living: where and how do the Roma live in J
p
p
g
p
Romany in Prekmurje", ActaGeograpca Slovenica, vol. 43, no. 1, p. 127-147. Jaksić, B. and Basić, G. (2005), The art of living: where and how do the Roma live in y
j
g
p
p
Jaksić, B. and Basić, G. (2005), The art of living: where and how do the Roma live in
Serbia, Institute of Philosophy and social theory, Belgrade. J
,
,
(
),
f
g
Serbia, Institute of Philosophy and social theory, Belgrade. Serbia, Institute of Philosophy and social theory, Belgrade. Jovanovich A (1998) Fertility and Family Planning in the Republic of Macedon Serbia, Institute of Philosophy and social theory, Belgrade. Jovanovich, A. (1998), Fertility and Family Planning in the Republic of Macedonia, p y
y
g
Jovanovich, A. (1998), Fertility and Family Planning in the Republic of Macedonia,
Metamorfoza, Skopje. References y
p
p
g
g
Qq
OSI, EU Monitoring and Advocacy Program (2007), Education support program
Roma participation program, Equal Access to Quality Education for Roma, vol. 2. 174 Biljana Apostolovska Toshevska et al. Republic of Macedonia. Packer, C. (2003), "Roma Women and Public Health Care in Sexual and Republic of Macedonia. Republic of Macedonia. Republic of Macedonia. Packer, C. (2003), "Roma Women and Public Health Care in Sexual and
Reproductive Health in a Multicultural Europe", The European Magazine for p
Packer, C. (2003), "Roma Women and Public Health Care in Sexual and
Reproductive Health in a Multicultural Europe", The European Magazine for
Sexual and Reproductive Health, no. 35, WHO: Regional ofce for Europe. Reproductive Health in a Multicultural Europe", The European Magazine for
Sexual and Reproductive Health, no. 35, WHO: Regional ofce for Europe. p
g
p
Pavić, D. (2013), "Birth Rates of Ethnic Groups in Croatia from 1998 to 2008",
Migration and Ethnic themes, vol. 29, no. 1, p. 39-62. Powell, R. and Lever, J. (2015), "Europe's perennial "outsiders": A processual
approach to Roma stigmatization and ghettoization", Current Sociology, viewed
20 April 2017, https://goo.gl/Wr8ASP. p
p
g
g
Ringold, D., Orenstein, A.M. and Wilken, E. (2005), Roma in an Expanding
Europe: Breaking the Poverty Cycle, The World Bank, Washington, DC. Si
N
(2003)
"'H
d b
f
?' K
R
d Ringold, D., Orenstein, A.M. and Wilken, E. (2005), Roma in an Expanding
Europe: Breaking the Poverty Cycle, The World Bank, Washington, DC. Sigona, N. (2003), "'How can a nomad be a refugee?' Kosovo Roma and
Labelling Policy in Italy", Sociology, vol. 37, no. 1, p. 69-79. Š p
g
y
y
,
,
g
,
Sigona, N. (2003), "'How can a nomad be a refugee?' Kosovo Roma and
Labelling Policy in Italy", Sociology, vol. 37, no. 1, p. 69-79. Š Šobot, A. (2009), "Understanding demographic realities from the gender
perspective", Demography, vol. VI, Faculty of Geography, Institute of
Demography, Belgrade, p. 51-63. Sprocha, B. and Bleh, B. (2017), Does socio-spatial segregation matter? 'Islands' of
high Romany fertility in Slovakia, Demographic research centre and center of
social and psychological sciences SAS, Bratislava, Slovakia. SSORM, (2004), Census of the Population, households, and dwellings, 2002, State
Statistical Ofce of the Republic of Macedonia, viewed 15 April 2017,
www.stat.gov.mk. Stojmilov, A. and Apostolovska Toshevska, B. (2015), Socioeconomic Geography of
the Republic of Macedonia, University of Ss. Cyril and Methodius, Skopje. References Tosi Cambini, S. and Beluschi Fabeni, G. (2017), "Antiziganisms Ethnographic
engagements in Europe", ANUAC, vol. 6, no. 1, p. 99-117. g g
p
p
Trbojević, S. and Bogoevska, N. (2011), "Migration, social exclusion and identity
issues of Macedonian Roma", Two Homelands, vol. 34, p. 137-147. UNFPA (2013), Adolescent pregnancy in Eastern Europe and Central Asia. United States Department of State (2009), 2008 Country Reports on Human Rights
Practices – Macedonia, viewed 12 April 2017, https://goo.gl/GMtJRY. van Baar, H. (2011), "Europe's Romaphobia: Problematization, Securitization,
Nomadization", Environment and Planning D: Society and Space, vol. 29, p. 203-
212. van Baar, H. (2012), "Socio-economic mobility and neo-liberal governmentality
in post-socialist Europe: activation and the dehumanisation of the Roma",
Journal of Ethnic and Migration Studies, vol. 38, no. 2, p. 1289–304. Vašečka, M., Jurásková, M. and Nicholson, T. (2003), CACIPEN PAL O ROMA A
Global Report on Roma in Slovakia, Institute for Public Affairs, Bratislava. Wertheimer Baletic, A. (1973), "Demography population and economic develop-
ment", Economic library VII circle, Informator, Zagreb.
|
https://openalex.org/W2927473281
|
http://www.scielo.org.za/pdf/sajae/v47n1/02.pdf
|
English
| null |
Evaluation of South Africa's public agricultural extension in the context of sustainable agriculture
|
Suid-Afrikaanse tydskrif vir landbouvoorligting/South African journal of agricultural extension
| 2,019
|
cc-by
| 8,327
|
1 R. H. Khwidzhili. PhD student at the University of KwaZulu-Natal and Lecturer: Agricultural Extension and
Rural Resource Management, University of Mpumalanga, P/Bag x 11283, Nelspruit, 1200. Tel. 013 002 0144; E
mail: humphrey.khwidzhili@ump.ac.za. This article is part of the author's PhD Thesis at the University of
KwaZulu-Natal, Pietermaritzburg Campus.
2 Prof. S. Worth. Associate Professor: Agricultural Extension and Rural Resource Management & Director:
African Centre for Food Security, School of Agricultural, Earth and Environmental Sciences. University of Kwa-
Zulu Natal, P/Bag X01, Scottsville, 3209. Tel. 033 2605792; E mail worths@ukzn.ac.za ABSTRACT South Africa’s public agricultural extension services evolved from as early as the beginning of
1900. Agricultural extension is now recognised as a science by the South African Council of
Natural Science Profession (SACNASP). This paper presents a philosophical argument that
the promotion of sustainable agricultural practices should remain the domain of public
extension and advisory services. To provide context, the paper firstly defines agricultural
extension and the role extension could play in promoting the five pillars of sustainable
agriculture. Secondly, it evaluates the national policy on extension and advisory services to
determine the extent to which it addresses the framework of the five pillars for sustainable
agriculture. Thirdly, the paper evaluates the Extension Recovery Plan (ERP), norms and
standards for agricultural extension and the National Development Plan (NDP) against the
framework of sustainable agriculture. The evaluation indicates that only three pillars of
sustainability are emphasised. There is a need to subdivide the traditional pillars to align with
the full framework for sustainability. The initial findings suggest that, while South Africa’s
agricultural extension policy often refers to sustainability and even to sustainable agriculture,
they do so using the traditional three-pillared framework of economic, environmental and
social sustainability, and thus fall short on key elements essential to sustainable agriculture,
namely maintaining and increasing biological productivity, decreasing the level of risk to
ensure larger security, protecting the quality of natural resources, ensuring agricultural
production is economically viable, and ensuring agricultural production is socially acceptable. The paper also explores government initiatives to support extension and advisory services. Finally, this paper concludes by emphasising that the national policy on extension and advisory
services should be amended to suit the five pillars of sustainable agriculture. Keywords: Sustainable agriculture, extension and advisory services, extension, pillars of
sustainability, agricultural policy EVALUATION OF SOUTH AFRICA’S PUBLIC AGRICULTURAL EXTENSION IN
THE CONTEXT OF SUSTAINABLE AGRICULTURE Khwidzhili, R. H.1 and Worth, S.2 Correspondence Author: R. H. Khwidzhili, Email: humphrey.khwidzhili@ump.ac.za S. Afr. J. Agric. Ext.
Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth
(License: CC BY 4.0) S. Afr. J. Agric. Ext. Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 S. Afr. J. Agric. Ext.
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 S. Afr. J. Agric. Ext. Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 S. Afr. J. Agric. Ext. (License: CC BY 4.0) understand the extent to which South Africa’s public extension service is positioned to promote
sustainable agriculture amongst the farmers it serves. This paper first examines the discipline
of agricultural extension in the context of sustainability and discusses the role it should play in
promoting sustainable agriculture. The paper then presents a brief outline of the evolution of
public sector extension in South Africa, and argues that, given the role extension has played
over the last several decades, the state extension service should be well-positioned to promote
sustainable agriculture even if this has not been its primary focus in the past. Furthermore, since
extension services are driven by policy, the paper examines the extent to which current South
African national policy guiding extension and advisory services supports the promotion of
sustainable agriculture using the five pillars of sustainable agriculture established by
Khwidzhili and Worth (2016). Other initiatives to support extension and advisory services are
also discussed. 2. OBJECTIVES OF THE PAPER The main objective of this study is to evaluate public agricultural extension in South Africa
and its alignments to the five pillars of sustainable agriculture. This entails the following: Defining agricultural extension and the role it plays in the agricultu Defining agricultural extension and the role it plays in the agricultural sector; Providing an overview of the evolution of agricultural extension in South Afric Evaluating the current national policy on extension and advisory services and other
public documents in the context of South Africa's extension services’ position to
promote sustainable agriculture with specific reference to the five-pillars framework;
and Providing guidance to policy makers for incorporating all five pillars of sustainable
agriculture when developing agricultural extension policies and programmes. Providing guidance to policy makers for incorporating all five pillars of sustainable
agriculture when developing agricultural extension policies and programmes. 3. RESEARCH METHOD This was a desk-top study examining relevant policies documenting the involvement of South
Africa's public extension services in the context of sustainable agriculture. The data analysed
were drawn primarily from existing articles, documents and policies filtered through the five
pillars of sustainable agriculture to identify embedded themes and recurring patterns of
meaning and relationships (Cohen, Manion & Morrison, 2002). This is a review paper based
on already existing literature (Yin, 2003), in other words, secondary data. The following
documents were evaluated as they were found to be relevant to the delivery of agricultural
extension in South Africa: National Policy on Extension and Advisory Services; Extension
Recovery Plan; and the Norms and Standards for Agricultural Extension and the National
Development Plan. 1. INTRODUCTION The continued provision of food, fuel and fibre to a growing world population depends, in large
measures, on the practice of sustainable agriculture. This paper argues that, in the case of South
Africa, adoption of sustainable agricultural practices falls in the domain primarily of public
sector agricultural extension (Department of Agriculture (DOA), 2014). It is thus valuable to 20 Khwidzhili & Worth S. Afr. J. Agric. Ext.
Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth S. Afr. J. Agric. Ext. (License: CC BY 4.0) http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 Agricultural extension began to take shape in South Africa around 1925, supported by the then
National Ministry of Agriculture. The Ministry had approved approximately six agricultural
advisors (extension officers) to serve the entire country in rendering extension services. The
primary role of extension from its initial stage was to assist farmers to make decisions that will
better their farming practices and ensure food security in the country (Koch & Terblanche,
2013). In the early 1940s, agricultural extension was incorporated as an academic career within
institutions of higher learning. This was initiated by the University of Pretoria, University of
Stellenbosch and Elsenberg College of Agriculture where the faculties of agriculture were
established (Van Vuuren, 1952). Over the ensuring decades, other South African universities
and colleges began to offer agricultural extension programmes. Among these are the
Universities of Fort Hare, KwaZulu-Natal, Limpopo, North West, Venda, Cape Peninsula
University of Technology, and Tshwane University of Technology (Koch & Terblanche,
2013). The now 11 agricultural colleges have also played an important role in training in
agricultural advisors, particularly for the former so-called homelands. Concurrent with the
expansion of extension in higher education, the profession of extension grew, and in 1966, the
South African Society of Agricultural Extension (SASAE) was established at the University of
Pretoria as a professional body supporting the extension practitioners. Despite its inclusion in higher education programmes, and despite its contribution to the
livelihood of farmers and the agricultural economy, for eight decades after the establishment
of extension, agricultural extension was not considered as a science by the South African
Council of Natural Science (SACNASP). However, the SASAE championed the cause of
extension with SACNASP, and since 2013, agricultural extension has been officially
recognised as a science (extension science) with three possible categories of registration
(depending on the nature of the extension practitioner’s qualification). The categories include
professional (post-graduate degree in agricultural extension coupled with relevant experience),
candidate (supported by a degree in agriculture with no experience in extension), and
certificated scientist (supported by a degree in agriculture and at least some experience in
agriculture). S. Afr. J. Agric. Ext.
Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) The adoption of the South African Constitution in 1994 established that board extension policy
(as an element of national aspects of agriculture) would be a national competency, while the
delivery and management of extension to farmers would be done through the provincial
governments, with substantial latitude regarding modes of operation, operational focus and
developmental priorities. This resulted in nine separate extension services, which, while being
bound to broad national policy, are not subject to any meaningful national coordination or
collective accountability, rather they are solely accountable to the provincial legislatures and
governments and ultimately individual provincial political leaders (Worth, 2012). 4. THE EVOLUTION OF PUBLIC AGRICULTURAL EXTENSION IN SOUTH
AFRICA The evolution of agricultural extension in South Africa dates back to the reconstruction that
followed from 1902 when agricultural scientists were imported from England. Drawing from
expertise of outsiders was futile as they were unfamiliar to South Africa's local conditions. In
response, in 1907, the first cohort of potential South African scientists was identified to study
abroad (Van Vuuren, 1952). 21 5. PUBLIC AGRICULTURAL EXTENSION PERSPECTIVE AND THE ROLE IT
PLAYS IN AGRICULTURE There is no single definition that can be used exclusively to define agricultural extension. According to the then South African Department of Agriculture (DOA, 2005), agricultural
extension is the art of assisting commercial, small-scale and subsistence farmers with
agricultural related knowledge and skills that will make them productive and competitive to
ensure sustainability (Hedden-Dunkhorst & Mollel, 1999). Van den Ban and Hawkins (1996)
earlier defined extension as the conscious use of communication of information with the aim
of assisting people to make good decisions. Purcell and Anderson (1997) similarly confirm that 22 S. Afr. J. Agric. Ext. Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth S. Afr. J. Agric. Ext. (License: CC BY 4.0) agricultural extension is a key element in enabling farmers to obtain information and
technologies that can improve their livelihoods. The concept of a livelihood is broader and
more comprehensive and integrated than simply ‘farming’. A livelihood is a means of
supporting one’s existence most often through multiple strategies of which, for farmers,
farming is one. Most commonly, extension is generally viewed as a process of working with farmers or farming
communities to help them acquire relevant and useful agricultural or related knowledge and
skills in order to increase farm productivity, competitiveness, and sustainability (Düvel, 2004). However, in practice, it is a continuum ranging from the narrow technology transfer focusing
specifically on farming practices within the specific context of an agricultural enterprise, to
advisory services that address farming and related practices in the wider context of social,
economic and environmental perspectives including education, human development and
critical public priority issues such as food security, poverty alleviation, environmental
degradation, and social equity (De Klerk et al., 2004). Increasingly, the role of agricultural extension extends beyond technology transfer with a
primary aim of assisting farmers to adopt new technology. Extension’s role encompasses
linking farmers to domestic and international markets, assisting farmers in reducing their
vulnerability and enhancing their livelihoods, promoting environmental conservation (Alex,
Zijp & Byerelee, 2001), and taking a leading role in rural development and even non-farm
employment (Rivera, Qamar & Crowder, 2001). Extension is expected to include strengthening
innovation processes and building linkages between farmers and other agencies, as well as
assisting farmers with bargaining for inputs and access to credit to advance their farming
practices (Aneato et al., 2012). Table 1 summarises some common agricultural extension models that are used in South Africa. 5. PUBLIC AGRICULTURAL EXTENSION PERSPECTIVE AND THE ROLE IT
PLAYS IN AGRICULTURE In this expansive context, it is evident that agricultural extension
requires a holistic approach. Agricultural extension is an important factor in promoting agricultural development (Anderson
& Feder, 2007; Birkhaeuser, Evenson & Feder, 1991). Most governments in sub-Saharan
Africa, including South Africa, have invested in agricultural extension as the primary tool for
improving agricultural productivity and farmers’ income. In South Africa, agricultural
extension is used to support agricultural development and specifically to play a pivotal role in
educating farmers to practice more efficient and profitable farming. It is thus posited that South
Africa’s public agricultural extension should be well-suited to promote sustainable agriculture. Agricultural extension services depend upon knowledge, skills, and insights concerning the
multifaceted process of behaviour change (Griffith, 1994). While extension should help teach
new farming practices and assist rural people to build leadership and organisational skills (Van
der Ban & Hawkins, 1996), more recently, extension has experienced a major shift towards
participatory models (Düvel, 2005) in which stakeholders take a more active role in agricultural
extension processes and decision-making. Most recently, there has been an introduction of a
learning-based model that emphasises the need to build capacity for learning throughout the
extension system, but especially among the farmers for which learning is described as the
capacity to engage with scientific enquiry (Worth, 2006). Table 1 summarises some common agricultural extension models that are used in South Africa. e 1 summarises some common agricultural extension models that are used in South Africa 23 S. Afr. J. Agric. Ext. Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) S. Afr. J. Agric. Ext. Khwidzhili & Worth
Vol. 47 No. 5. PUBLIC AGRICULTURAL EXTENSION PERSPECTIVE AND THE ROLE IT
PLAYS IN AGRICULTURE 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0)
Table 1: Extension models
Models
Core principles
Implications
Linear
- Top-down approach
- Based on extension expertise
- The farmer is the recipient
- Farmers cannot solve their
problems
- Adoption of technology is not
questionable by farmers
- Farmers less interested
Advisory
- Farmers solve their problems
- Extension required on farmer's
request
- Based on farmer's expertise
- Extension is the last option
- Extension has less influence
- Farmers solve their own problems
Participatory
- All stakeholders participate
- Encourage mutual respect
- Joint problem solving
- Everyone feels important
- Expertise from both participants
Learning
- Based on learning from each other
- Based on continuous reflection
from both parties
- Collective decisions are taken and
based on both parties’ expertise
- Create sustainable relation
- Encourage learning and research
- Some participants might be
illiterate
Adapted from Abdu-Raheem and Worth (2011) S. Afr. J. Agric. Ext. Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth
(License: CC BY 4.0) Depending on the aim and objective of an extension engagement or intervention, different
extension models are used by extension. The first extension model in Depending on the aim and objective of an extension engagement or intervention, different
extension models are used by extension. The first extension model in Table 1 is called the linear model which focuses on transfer of technology in which the (mostly
off-farm) extension research centre is the source of technology and innovation that is then
‘transferred’ to farmers who ‘adopt’ the technology (Röling, 1995). This is a so-called ‘top-
down approach’ because the farmer is only the recipient of technology that has been designed
and delivered ‘from above.’ The linear model requires high-level knowledge from specialised
scientists and specialised extension skills to disseminate innovations to farmers (Dexter, 1986). However, not all farmers will adopt all new technology from extension practitioners, especially
technology developed in their absence. Adoption of technology is influenced by the farmers’
resources and their past experience. Thus, this approach is not appropriate in all cases, and
should not be the ‘default’ approach. The second extension model is the advisory model which views farmers as active problem
solvers and will seek advice from extension only if they fail to solve their problems themselves
(Röling, 1995). S. Afr. J. Agric. Ext.
Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth S. Afr. J. Agric. Ext. (License: CC BY 4.0) http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 from past generations, but which is no longer used), local practice (knowledge compiled from
various second-hand sources or unstructured trial and error), and/or local science (knowledge
and practices currently in use or not a result of deliberate and conscious innovation and
experimentation conducted by the farmer) (Masere & Worth, 2016). Local science would result
from an extension engagement that employs a learning posture with the primary aim of building
capacity of farmers to learn, innovate and experiment systematically, methodically and
deliberately (Worth, 2006). Thus, extension should recognise farmers’ knowledge and should
incorporate it in their work (Agrawal, 1995; Hart, 2003; Swanson, 2006). from past generations, but which is no longer used), local practice (knowledge compiled from
various second-hand sources or unstructured trial and error), and/or local science (knowledge
and practices currently in use or not a result of deliberate and conscious innovation and
experimentation conducted by the farmer) (Masere & Worth, 2016). Local science would result
from an extension engagement that employs a learning posture with the primary aim of building
capacity of farmers to learn, innovate and experiment systematically, methodically and
deliberately (Worth, 2006). Thus, extension should recognise farmers’ knowledge and should
incorporate it in their work (Agrawal, 1995; Hart, 2003; Swanson, 2006). The fourth model is a learning-centred model which focuses on learning amongst agricultural
extension workers, researchers, farmers and other stakeholders. The model is based on
continuous reflection amongst all stakeholders within the learning process (Worth, 2006). This
model was evolved from the facilitation model and Chambers’ (1997) participatory rural
appraisal (PRA). It is grounded in Kolb’s (1984) learning theory which embraces the iterative
process of analysing, planning, acting, monitoring and evaluating (i.e. observing, reflecting,
conceptualising and actively experimenting). The fourth model is a learning-centred model which focuses on learning amongst agricultural
extension workers, researchers, farmers and other stakeholders. The model is based on
continuous reflection amongst all stakeholders within the learning process (Worth, 2006). This
model was evolved from the facilitation model and Chambers’ (1997) participatory rural
appraisal (PRA). It is grounded in Kolb’s (1984) learning theory which embraces the iterative
process of analysing, planning, acting, monitoring and evaluating (i.e. observing, reflecting,
conceptualising and actively experimenting). As noted earlier, no one extension model is suitable in all contexts. 5. PUBLIC AGRICULTURAL EXTENSION PERSPECTIVE AND THE ROLE IT
PLAYS IN AGRICULTURE The model encourages farmers to share information and learn from each other
with little influence from extension services. The advice from extension comes as a request
from the farmer. The model recognises and appreciates the role that farmers could play in
problem solving. The third model is the participatory model where the knowledge and expertise of farmers (often
referred to as indigenous knowledge) have accumulated over generations (Agrawal, 1995). This knowledge is best understood as local memory (the collection of practices handed down 24 S. Afr. J. Agric. Ext.
Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) However, it can be argued
that the participation of both the extension practitioner and farmers in addressing farmers’
issues can yield profound benefits. It is thus imperative, whatever model is applied, that
learning should be encouraged and promoted, as it is the basic component of knowledge
management. Each stakeholder should be treated with respect and be afforded the opportunity
to display and apply their expertise. These shifts in approach and process suggest that extension services respond well to working
within the bounds of theoretical frameworks, including those guiding sustainable agricultural
practices (Rivera, 2006). Existing frameworks could be adopted, adjusted or developed and
adapted to extension’s multiple roles ranging from advisory, technician, educator, middleman,
facilitator, analyst, researcher and learning partner (Bembridge, 1991; DOA, 2005, Düvel,
2005; Van den Ban & Hawkins, 1996; Worth 2006). Globally, public agricultural extension is
faced with a large challenge of being relevant and effective. To achieve this, it is essential to
develop and implement relevant frameworks. A case in point is a framework for sustainable agriculture. Currently, with regards to
sustainable agriculture, agricultural extension advises farmers based on the three traditional
pillars of sustainability, namely economic, environmental and social viability (Magoro &
Hlungwani, 2014). However, more current thinking suggests that a five-pillar framework
should be applied (Khwidzhili & Worth, 2016) which encompasses maintaining and increasing
biological productivity, decreasing the level of risk to ensure larger security, protecting the
quality of natural resources, ensuring agricultural production is economically viable, and
ensuring agricultural production is socially acceptable. The national policy on agricultural extension and advisory services has clearly defined the role
of agricultural extension agents. The study also supports the four extension models described
by Abdu-Reheem and Worth (2011), which extension can use to promote sustainable
agriculture. As previously noted, no single approach suits all environments. Extension will
have to choose approaches that will be relevant to their target clients (farmers), their situations,
and the issues to be addressed. However, the failure of the exclusive use of conventional top-down approaches which excluded
farmers participation is well documented. Thus, in general, agricultural extension should 25 S. Afr. J. Agric. Ext. Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth S. Afr. J. Agric. Ext. (License: CC BY 4.0) prioritise participatory approaches when engaging farmers. S. Afr. J. Agric. Ext.
Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Leeuwis and Van den Ban (1996),
for example, argued that farmers should be involved directly in the planning of agricultural
extension activities. Participatory agricultural extension encourages joint learning amongst
farmers (Hagmann et al, 1999; Wettasinha, Veldhuizen & Waters-Bayer, 2003). Promoting
participation of farmers in the extension process reduces barriers that impact the rate of
adopting sustainable agricultural practices (Ajeigbe & Dashiell, 2010). Specifically, according
to Nagel (1997), understanding, working with, accommodating and otherwise building on the
local knowledge of farmers helps promote sustainable agricultural practices. Early in the provision of extension to smallholder black South African farmers, Bembridge
(1979) argued that extension services were meant to transfer skills and knowledge to farmers. This suggests that the knowledge and skills held within the agricultural extension system
should be assessed and updated on a regular basis to ensure extension services stay relevant to
the ever-changing agricultural landscape. In addition to the knowledge and skills within extension and the choice of extension models
and frameworks, the reach of the service is also an important factor. Williams et al. (2008)
reported that access to quality extension and advisory services depends on the ratio of extension
to farmers. The lack of distribution of extension and advisory services in South Africa was also
highlighted as a major constraint for farmers (Ndoro, Mudhara & Chimonyo, 2014; Nel &
Davies, 1999; Van Niekerk et al., 2011). They argued that the distribution of extension and
advisory services is relatively low among emerging farmers (who arguably have the greatest
need for extension), compared to so-called commercial farmers. The poor distribution
contributes to the fact that most emerging farmers depend entirely on public extension services
(Ngomane, Thomson & Radhakrishna, 2002; Oladele & Mabe, 2010), while commercial
farmers rely on private extension that is often costly. Similarly, the South African Extension
Recovery Implementation Plan (2008) indicated a lack of adequate extension services in the
country, indicating the ratio of extension officers to farmers as 1:1500. This figure is still high
considering that some farms are commercial (the scope of work is extended) while others are
producing on a small scale. In addition, factors such as low morale, lack of mobility, and low
salaries were found to contribute to high turnover in the extension services, and make it difficult
to attract recruits (Belay & Abebaw, 2004; Kaimowitz, 1991). The recovery plan was designed
to address these various challenges in South African extension 6. REVIEW OF SECONDARY SOURCES The study examined four public documents that are considered fundamental in promoting
agricultural extension and advisory services in South Africa, namely the National Policy on
Extension and Advisory Services, Norms and Standards for Agricultural Extension, Extension
Recovery Plan, and the National Development Plan. A brief overview of these policies is
presented below. http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 The policy notes that South African extension faces “major challenges in the areas of relevance,
efficiency, accountability and sustainability” and that it needs to be sufficiently flexible to
“respond to a wide set of local, national and global pressures to the agriculture, forestry and
fishery sectors across [many] value chains” (DOA, 2014:4). The policy does not specifically
provide details on the sustainability of extension, however, it does provide some clues. The
policy suggests that extension is sustainable when: -
Extension operates within a “developmental and systems approach” in which extension
workers “have a holistic view and understand the total value chain and linkages”; -
Extension operates within a “developmental and systems approach” in which extension
workers “have a holistic view and understand the total value chain and linkages”; g
-
Extension is governed and operates within a common set of principles and values; -
Extension genuinely responds to the needs, aspirations, opportunities and other
circumstances of the many actors in the respective value chains; -
Extension workers trained with a multidisciplinary approach capacitating them with
relevant and diverse knowledge and tools while retaining subject-specific technical
knowledge and skills; -
Extension reaches beyond just production aspects of farming and addresses other
elements of the value chain and subsectors such as forestry and fisheries – and these in
the context of sustainable economic development; -
A holistic and collaborative approach is applied in a truly decentralised and pluralistic
approach in which all role-players, stakeholders and service providers work together
and share knowledge and information; and -
The extension service is directly accountable to clients at field level (DOA, 2014: 4 Figure 1 portrays the proposed arrangement for coordinating and delivering extension in South
Africa. The National Department of Agriculture, Forestry and Fisheries (DAFF) will establish
a National Extension Forum whose members are drawn from public, private and NGO-sector
stakeholders and role-players within the agri-food system. Each of South Africa’s nine
provinces (these include Gauteng (GP), Free State (FS), Mpumalanga (MP), Limpopo (L),
Eastern Cape (EC), Western Cape (WC), Northern Cape (NC), North West (NW), and Kwa-
Zulu Natal (KZN)) will have a provincial extension coordinating forum as well as district
extension forums through the province (DOA, 2014). The forums will articulate, prioritise and
coordinate the provision of extension and advisory services within their respective designated
geographical areas. 6.1 National Policy on Extension and Advisory Services (NPEAS) South Africa developed a national policy on extension and advisory services in order to set a
regulatory framework to guide public and private extension throughout the country (DOA,
2014). The policy states that extension and advisory services should be relevant, efficient,
accountable and sustainable, and that extension should support sustainable agriculture. 26 Khwidzhili & Worth S. Afr. J. Agric. Ext. (License: CC BY 4.0) http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 6.2 Extension Recovery Plan The Extension Recovery Plan (ERP) was developed to capacitate or revitalise extension and
advisory services in the country. This initiative sought to address various challenges and
limitations in the sustainability of farmers and farming activities. The five strategic objectives
or pillars of the ERP initiative are to: ensure visibility and accountability of extension; promote
professionalism and improve the image of extension; recruit extension personnel; re-skill and
re-orientate extension workers; provide information and communication technology (ICT) and
other resources (DOA, 2011). http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 Similar to the National Forum, provincial and district forums will comprise of relevant
stakeholders from the public, private and NGO sectors, including farmers and others in the
value chain. The composition of the forum is determined by the policy and may be extended
or reduced depending on the scope of the forum. Information relevant to coordinating extension
should flow in all directions within the system – not merely top-down. This underscores the
intended collaborative mode of this proposed approach to coordinating extension. It is also in
keeping with operating holistically and collaboratively using a systems approach and makes
extension more accountable at the ‘field level’ – all of which are needed to ensure the
sustainability of extension. Although not expressively articulated in the policy, this proposed
arrangement for coordination will also encourage and facilitate learning. 27 Khwidzhili & Worth S. Afr. J. Agric. Ext. g
Vol. 47 No. 1, 2019: 20 - 35 Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0)
Figure 1: Institutionalisation of extension coordination forum in South Africa
Adapted from Draft National Policy on Extension and Advisory services (DOA, 2014). It may consist of
Districtl Extension
Coordinators,Priva
te representatives,
Social
representatives. Research,
Academics,
Producers,
Associations and
others
FS
MP
L
EC
WC
NC
NW
KZ
G
P
National Extension Coordinating Forum
Provincial Extension Coordinating Forum
District Extension Coordinating Forum
Local 2
It may consist of
National
Department of
Agriculture,
Provincial
Extension
Coordinators,Priva
te representatives,
Social
representatives. Research,
Academics,
Producers,
Associations and
It may consist of
Provincial
Extension
Coordinators,Priva
te representatives,
Social
representatives. Research,
Academics,
Producers,
Associations and
others
Local
1
Local
3 (License: CC BY 4.0) (License: CC BY 4.0) National Extension Coordinating Forum National Extension Coordinating Forum Provincial Extension Coordinating Forum Provincial Extension Coordinating Forum District Extension Coordinating Forum Local Figure 1: Institutionalisation of extension coordination forum in South Africa
Adapted from Draft National Policy on Extension and Advisory services (DOA, 2014). 7. FINDINGS AND IMPLICATIONS OF THE STUDY The main objective of this study was to evaluate South African public agricultural extension
and its alignment to the five pillars of sustainable agriculture. The premise of the study was
that there is no inclusive policy dealing specifically with sustainable agricultural practices in
South Africa (Khwidzhili & Worth, 2017). Thus, it was necessary to study various policies to
determine the criteria being used when discussing or promoting sustainable agriculture. To
facilitate this discussion, each of the five pillars is discussed. 6.3 Norms and Standards for Agricultural Extension (NSAEAS) Norms and Standards for South African Extension and Advisory Services were also developed
as a result of a lack of framework for these services (DOA, 2005). Among other objectives, the
Norms and Standards promote participatory approaches to extension and advisory services that
lead to sustainable income generation by extension’s clients in the context of fostering learning 28 S. Afr. J. Agric. Ext. Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth S. Afr. J. Agric. Ext. (License: CC BY 4.0) http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 on sustainable agricultural production, including the conservation of natural resources. The
Norms and Standards specifically define sustainability with seven factors, namely productivity,
risk reduction, protection of the environment, economic viability, social acceptability, technical
feasibility, and commercial feasibility (DOA, 2005). In addition, the Norms and Standards emphasise strengthening the link between research,
extension and farmers to promote research that supports sustainable agriculture. Finally, the
Norms and Standards also emphasise the need to revitalise curriculum at institutions of higher
education. The curriculum should enable extension practitioners to address issues such as
increasing food security, economic growth, globalisation and environmental conservation
(DOA, 2005). 6.4 National Development Plan The National Development Plan (NDP) is considered a major step in the process of charting a
new path for the Republic of South Africa – including promoting agriculture as an important
path to eliminate poverty, reduce inequalities and redress the imbalances caused by apartheid. It is anticipated that much agricultural land will be urbanised which potentially creates
uncertainties regarding food production and food insecurity. The NDP encourages moving
away from unsustainable use of natural resources, expressing the need to reduce carbon
emissions, and the concern that water for agriculture and drinking is becoming scarce and
exhorting farmers to use water-conserving irrigation methods. The NDP also addresses social protection in terms of improving livelihoods, pronouncing that
eliminating poverty and reducing inequalities are the main drivers of social solidarity. The NDP
emphasises that South Africa’s agricultural potential is much larger than its current output; that
the low potential is as a result of poor access to agricultural land and environmental degradation
of land controlled by foreign and private entities. The NDP proposes a ‘green revolution’ to
encourage food security by promoting sustainable agriculture among smallholder farmers. S. Afr. J. Agric. Ext.
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 (License: CC BY 4.0) function of innovation. The NDP emphasises the production of food to eliminate food
insecurity by 2030. 7.3 Protecting the quality of natural resources This pillar is well-emphasised in all four policies. This is not unexpected as it originates from
the three traditional pillars of sustainable agriculture. It is, however, always referred to as
environmental viability. It is noted that the policies, not dissimilar to literature on sustainable
agriculture, integrate this pillar with biological productivity – masking the distinct role of
biological productivity in sustainable agriculture. This is the case with the NPESA and the ERP
which define this pillar in terms of environmental viability. The NSAEAS specifically refers
to the objectives of “endowing farmers with skills and knowledge for ensuring sustainable
resource management” (DOA, 2005:2) and cites this as a specific function of extension. The NDP refers specifically to the need to address the “extreme pressure on natural resources”,
which resources it states, “include its adjacent oceans, soil, water, biodiversity, sunshine and a
long coastline” (NDP, 2013:47). To achieve this, the intention is to establish an environmental
framework that indicates which natural resources need to be publicly monitored. As noted, the
NDP makes specific reference to “long-term planning to promote biodiversity and the
conservation and rehabilitation of natural assets” (NDP, 2013:201). Specifically needing
attention is “damage to the environment includes soil loss due to erosion, loss of soil fertility,
salination and other forms of degradation” and the harmful practices where “water extraction
for irrigation is exceeding rates of replenishment” (NDP, 2013:92). 7.2 Decreasing the level of risk to ensure larger security This pillar is often confused with economic viability. While they are related, they are separate
elements of sustainability. The NPEAS and the ERP both conflate risk and economic viability
into the traditional economic viability pillar of sustainability, thus, losing the nuance of risk
which is inherent in agricultural production and therefore cannot be totally eliminated. The
ERP refers to risk in relation to agriculture, noting only that extension should (among other
things) address “dealing with changing patterns of risk” and that risk reduction is part of
sustainable production (DOA, 2011:1). The NDP broadly discusses risk across all development
endeavours covered by the policy, and in particular, lifestyle risks faced by individuals. Specifically, it refers to climate-change risk and the related risk of insufficient irrigation water. It raises concern regarding bio-security risk in the context of promoting export-quality
production from smallholder farmers, however, it does not specifically speak to risk in
agricultural development as an element of sustainability. 7.1 Maintaining and increasing biological productivity The NPEAS refers several times to improving productivity of agricultural production, with an
emphasis on the production of food. However, no reference is made to organic matter in the
soil, which is a key factor in sustained productivity. The ERP developed to capacitate extension
and advisory services, focuses on improving the role of extension and advisory services with
reference to promoting sustainable agricultural practices. However, no reference is made to
biological productivity. The NSAEAS provides a framework for conducting extension, with
specific reference to “improved agricultural productivity” (DOA, 2011:2) and includes it as
part of sustainability (DOA, 2011:4), but with little elucidation about it except that it is a 29 S. Afr. J. Agric. Ext.
Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth
(License: CC BY 4.0) Khwidzhili & Worth
(License: CC BY 4.0) Khwidzhili & Worth 7.5 Ensuring agricultural production is socially acceptable Like economic viability, social acceptability is also one of the original pillars of sustainability
and it should appear in each of the policies reviewed. Surprisingly, there is little reference to
social acceptability in agriculture. The NPEAS notes that extension should lead to “wise
decision‐making about the socially…sustainable use of resources” in farmers’ efforts to
advance their livelihoods. It also notes that, in the pursuit of commercialisation, more attention
must be given to social impacts of commercialisation. The NSAEAS indicates that extension
“projects/ activities must... consider… social…impacts” and includes “social acceptability” as
a part of its definition of sustainability (DOA, 2014:4). The ERP makes no reference to social
acceptability in any context. The NDP considers social acceptability as fundamental to
sustainable development. It refers to the need to produce food that is socially acceptable. S. Afr. J. Agric. Ext.
Khwidzhili & Wor
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4 Khwidzhili & Worth
(License: CC BY 4.0) Khwidzhili & Worth
(License: CC BY 4.0) Khwidzhili & Worth S. Afr. J. Agric. Ext. (License: CC BY 4.0) http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 “commercial feasibility”) as a part of its definition of sustainability (DOA, 2014:4). The ERP
makes no mention of economically viable agricultural production. The NDP alludes to the need
for land reform to result in economically viable agricultural production; otherwise it makes no
reference to the economic viability of agriculture. 7.4 Ensuring agricultural production is economically viable This is one of the three traditional pillars of sustainable agriculture. Thus, it would be
reasonable to expect to find reference to it in each of the policies reviewed. However, this is
not the case. The NPEAS refers to economic viability in the context that extension should foster
“economic sustainability of the agriculture, forestry and fishery sectors” (DOA, 2014:4), and
with specific reference to land reform. The NSAEAS indicates that extension “projects/
activities must consider economic impacts” and includes “economic viability” (together with 30 S. Afr. J. Agric. Ext.
Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth
(License: CC BY 4.0) Khwidzhili & Worth S. Afr. J. Agric. Ext. (License: CC BY 4.0) http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 appointed as an extension practitioner if they are not registered with SACNASP. Registration
to SACNASP should be preceded by registering to the South African Society of Agricultural
Extension. SASAE is the voluntary organisation which acts as a mouthpiece of advocating
extension and advisory services in the country. Finally, the establishment of a national policy
on sustainable agricultural practices would serve as a compliment for the national policy on
extension and advisory services in South Africa. appointed as an extension practitioner if they are not registered with SACNASP. Registration
to SACNASP should be preceded by registering to the South African Society of Agricultural
Extension. SASAE is the voluntary organisation which acts as a mouthpiece of advocating
extension and advisory services in the country. Finally, the establishment of a national policy
on sustainable agricultural practices would serve as a compliment for the national policy on
extension and advisory services in South Africa. 8. CONCLUSION This paper provided a succinct evolution of agricultural extension in South Africa with special
emphasis that extension services were imposed on farmers through the transfer of technology
extension approaches. Since its inceptions in South Africa, agricultural extension is now
recognised by the South African Council for Natural Science Profession (SACNASP). This
implies that agricultural extension practitioners should register as scientists. The implication
for this is that extension should work under a code of conduct regulated by SACNASP. Drawing from the evidence presented in this paper, it can be argued that South African public
agricultural extension is best placed to promote sustainable agriculture through the five pillars
of sustainability. Apart from the conventional approaches, there are a number of models that
the extension could use to disseminate information. The definition of agricultural extension
was highlighted starting from the early years, beginning of the second millennium and beyond. The paper highlighted the role of public extension services in South Africa. The promotions of sustainable agricultural practices amongst farmers remains the domain of
public extension in South Africa. Central to promotion of sustainable agricultural practices is
the knowledge, skills and insight concerning the multifaceted process of changing farmers'
behaviours. The national policy on extension and advisory services serves as a framework
guiding the role of different stakeholders that are involved in public extension services. The
extension and advisory policy supports the establishments of extension coordinating forums
ranging from districts, provincial and national. These forums will be vital in promoting
sustainable agricultural practices provided that all stakeholders remain relevant. Judging from
its composition, which ranges from researchers, academics, private sector, associations, social
representatives and others, these forums could play a pivotal role in shaping the landscape of
extension and advisory services in South Africa. The paper also identified other initiatives by the government to support extension and advisory
services. These initiatives include, amongst others, the extension recovery plan (ERP) and the
norms and standards for extension and advisory services. The paper also confirmed that a four
year degree in agriculture is required in order to practice extension and advisory services in
South Africa. The study also observed that in a few years to come, no one will be allowed or 31 S. Afr. J. Agric. Ext. Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0)
appointed as an extension practitioner if they are not registered with SACNASP. 8. CONCLUSION Registration
to SACNASP should be preceded by registering to the South African Society of Agricultural
Extension. SASAE is the voluntary organisation which acts as a mouthpiece of advocating
extension and advisory services in the country. Finally, the establishment of a national policy
on sustainable agricultural practices would serve as a compliment for the national policy on
extension and advisory services in South Africa. S. Afr. J. Agric. Ext. Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) REFERENCES ABDU-RAHEEM, K.A. & WORTH, S.H., 2011. Household food security in South Africa:
Evaluating extension's paradigm relative to the current food security and development
goals. S. Afr. J. Agric. Ext., 39(2):91-103. AGRAWAL, A., 1995. Indigenous and scientific knowledge: Some critical comments. Indigenous Knowledge Monitor, 3(3):1-6. AJEIGBE, H.A. & DASHIELL, K., 2010. Participatory research extension approach: N2Africa
extension method. Putting nitrogen fixation to work for smallholder farmers in Africa
(N2Africa). International Institute of Tropical Agriculture (IITA). ALEX, G., ZIJP, W. & BYERELEE, D., 2001. Rural extension and advisory services - New
directions. Rural development strategy background paper No. 9, Washington, D.C:
Agriculture and Rural Development Department, World Bank. ANAETO, F.C., ASIABAKA, C.C., NNADI, F.N., AJAERO, J.O., AJO, O.O., UGWOKE,
F.O., UKPONGSON, M.U. & ONWEAGBA, A.E., 2012. The role of extension officers
and extension services in the development of agriculture in Nigeria. J. Agric. Res.,
1(6):180-185. ANDERSON, J.R. & FEDER, G., 2007. Agricultural extension, in Evenson, R. & Pingali, P
(eds.). Handbook of Agricultural Economics, vol. 3, Elsevier, 2343-2378. BELAY, K. & ABEBAW, D., 2004. Challenges facing agricultural extension agents: A case
study from South Western Ethiopia. Afr. Dev. Rev., 16(1):139-168. BEMBRIDGE, T.J., 1979. Effective agricultural extension. SA Institute for Agricultural
Extension Natal Branch SASAE. BEMBRIDGE, T.J., 1991. The practice of agricultural extension: A training manual. Development Bank of Southern Africa. BIRKHAEUSER, D., EVENSON, R.E. & FEDER, G., 1991. The economic impact of
agricultural extension: A review. Econ. Dev. Cult. Change, 39(3):607–640. CHAMBERS, R., 1997. Whose reality counts? Putting the first last. London: Intermediate
Technology. COHEN, L., MANION, L. & MORRISON, K., 2002. Research methods in education. Routledge. 32 S. Afr. J. Agric. Ext. Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth
(License: CC BY 4.0) Khwidzhili & Worth (License: CC BY 4.0) DE KLERK, M., DRIMIE, S., ALIBER, M., MINI, S., MOKOENA, R., RANDELA, R.,
MODISELLE, S., VOGEL, C., DE SWARDT, C. & KIRSTEN, J., 2004. Food security
in South Africa: key policy issues for the medium term. Human Sciences Research
Council. DEPARTMENT OF AGRICULTURE (DOA)., 2005. Norms and standards for extension and
advisory services in agriculture. Directorate: Scientific Research Development. Pretoria:
Republic of South Africa. DEPARTMENT OF AGRICULTURE (DOA)., 2011. Annual Report. Performance of the
Extension Recovery Plan. National Department of Agriculture, Forestry and Fisheries;
Pretoria: Republic of South Africa. DEPARTMENT OF AGRICULTURE (DOA), 2014. S. Afr. J. Agric. Ext.
Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486
(License: CC BY 4.0) Khwidzhili & Worth
(License: CC BY 4.0) (License: CC BY 4.0) (License: CC BY 4.0) KOCH, B.H. & TERBLANCHE, S.E., 2013. An overview of agricultural extension in South
Africa. S. Afr. J. Agric. Ext., 41(1):107-117. KOCH, B.H. & TERBLANCHE, S.E., 2013. An overview of agricultural extension in South
Africa. S. Afr. J. Agric. Ext., 41(1):107-117. REFERENCES National policy on extension and
advisory services. National Department of Agriculture, Forestry and Fisheries. Pretoria:
Republic of South Africa. DEXTER, E., 1986. Strategies in the transfer of agricultural technology, with reference to
Northern Europe, in Jones G.E. (ed.), Investing in rural extension: Strategies and goals,
London: Elsevier Applied Science Publishers, 121-127. DÜVEL, G.H., 2004. Developing an appropriate extension approach for South Africa: Process
and outcome. S. Afr. J. Agric. Ext., 33(1):1-10. DÜVEL, G.H., 2005. Principles, realities and challenges regarding institutional linkages for
participatory extension and rural development in South Africa. S. Afri. J. Agric. Ext.,
34(2):188-200. EXTENSION RECOVERY IMPLEMENTATION PLAN., 2008. Presentation done during
Department of Agriculture workshops and meetings in 2007-2008. GRIFFITH, W.S., 1994. Applying learning theory in extension work, in Blackburn, D.J. (ed.),
Extension handbook: Processes and practices. Toronto: Thompson Educational
Publishing. HAGMANN, J., CHUMA, E., MURWIRA, K. & CONNOLLY, M., 1999. Putting process
into practice: Operationalising participatory extension. Odi Agricultural Research &
Extension Network, Network Paper No. 94. HART, T.G.B., 2003. Land reform: What have we learned? S. Afri. J. Agric. Ext., 33(1):15-27. HEDDEN-DUNKHORST, B. & MOLLEL, N.M., 1999. Small-scale farming and extension in
South Africa’s Northern Province S. Afr. J. Agric. Ext., 28:93-107. KAIMOWITZ, D., 1991. The Evolution of Links between Extension and Research in
Developing Countries, in Rivera, W.M. & Gustafson, D.J. (eds.), Agricultural Extension:
Worldwide Institutional Evolution and Forces for Change, Amsterdam: Elsevier Science,
101–12. 33 KOLB, D.A., 1984. Experiential learning: Experiences as source of learning and development.
Eglewood Cliffs, NJ: Prentice Hall. KOLB, D.A., 1984. Experiential learning: Experiences as source of learning and development. Eglewood Cliffs, NJ: Prentice Hall. KHWIDZHILI, R.H. & WORTH, S.H., 2016. The sustainable agriculture imperative:
Implications for South African agricultural extension. S. Afr. J. Agric. Ext., 44(2):19-29. KHWIDZHILI, R.H. & WORTH, S.H., 2017. Evaluation of policies promoting sustainable
agriculture in South Africa. S. Afr. J. Agric. Ext., 45(2):73-85. LEEUWIS, C. & VAN DEN BAN, A., 1996. Communication for rural innovation: Rethinking
agricultural extension. Oxford, UK: Blackwell Science MAGORO, M.D. & HLUNGWANI, S.S., 2014. The role of agricultural extension in the 21st
century: Reflections from Africa. Int. J. Agric. Ext., 2(1):89-93. MASERE, T.P. & WORTH, S., 2016. Applicability of APSIM in decision-making by small-
scale resource-constrained farmers: A case of lower Gweru communal area, Zimbabwe. JIAEE, 22(3):20-34. NAGEL, U.J., 1997. Alternative Approaches to Organizing Extension, in Swanson, B., Bentz,
R.P., & Sofranko, A.J. (eds.), Improving Agricultural Extension: A Reference Manual,
Roma: FAO. NATIONAL DEVELOPMENT PLAN., 2013. Our future - make it work: National
Development Plan 2030. National Planning Commission NDORO, J.T., MUDHARA, M. & CHIMONYO, M., 2014. Livestock extension programmes
participation and impact on smallholder cattle productivity in KwaZulu-Natal: A
propensity score matching approach. S. Afr. J. Agric Ext., 42(2):62-80. NGOMANE, T., THOMSON, J.S. & RADHAKRISHNA, R.B., 2002. Public sector for the
agricultural extension systems in the Northern Province of South Africa. JIAEE., 9(3):32-
37. NEL, E. & DAVIES, J., 1999. Farming against the odds: An examination of the challenges
facing farming and rural development in the Eastern Cape Province of South Africa. Appl. Geogr., 19(3):253–274. NEUCHATEL GROUP, 2002. Common framework on financing agricultural and rural
extension, Lindau: Swiss Centre for Agricultural Extension and Rural Development. OLADELE, O.I. & MABE, L.K., 2010. Job burnout and coping strategies among extension
officers in North West province, South Africa. Afr. J. Agric. Res., 5(17):2321-2325. PURCELL, D.L. & ANDERSON, J.R., 1997. Agricultural extension and research:
Achievements and problems in national systems. The World Bank. 34 34 S. Afr. J. Agric. Ext. Khwidzhili & Worth
Vol. 47 No. 1, 2019: 20 - 35
h
//d d i
/10 17159/2413 3221/2019/ 47 1 486
(Li
CC BY 4 0) Khwidzhili & Worth g
Vol. 47 No. 1, 2019: 20 - 35 (License: CC BY 4.0) (License: CC BY 4.0) http://dx.doi.org/10.17159/2413-3221/2019/v47n1a486 RIVERA, W.M., 2006. Agricultural knowledge and development in a new age and a different
world. JIAEE, 13(2):57–67. RIVERA, W.M., QAMAR, M.K. & CROWDER, L.V., 2001. Agricultural and rural extension
worldwide: Options for institutional reform in the developing countries. Rome: FAO. RÖLING, N., 1995. Extension science. Cambridge: Cambridge University Press. SWANSON, B.E., 2006. The changing role of agricultural extension in a global economy. JIAEE, 13(3):5-17. VAN DEN BAN, A.W. & HAWKINS, H.S., 1996. Agricultural extension. Oxford: Blackwell
Science. VAN NIEKERK, J.A., STROEBEL, A., VAN ROOYEN, C.J., WHITFIELD, K.P. &
SWANEPOEL, F.C.J., 2011. Towards redesigning a new agricultural extension services
in South Africa: Views and proposals of extensionists in the Eastern Cape. S. Afr. J. Agric. Ext., 38:57-68. VAN VUUREN, J.P.J., 1952. Agricultural extension services. Farming in South Africa,
27(312):227-230. WETTASINHA, C., VELDHUIZEN VAN, L. & WATERS-BAYER, A., 2003. Advancing
participatory technology development: Case studies on integration into agricultural
research, extension and education. Philippines: IIRR. WILLIAMS, B., MAYSON, D., DE SATGÉ, R., EPSTEIN, S. & SEMWAYO, T., 2008. Extension and smallholder agriculture: Key issues from a review of the literature. Cape
Town: Phuhlisani. WORTH, S.H., 2006. Agriflection: A learning model for agricultural extension in South
Africa. The Journal of Agricultural Education and Extension, 12(3):179–193. WORTH, S., 2012. Agricultural extension in South Africa: Status Quo Report. Cape Town:
Phuhlisani Solutions. YIN, R.K., 2003. Case study research design and methods. California: SAGE Publications. , R.K., 2003. Case study research design and methods. California: SAGE Publications. 35
|
https://openalex.org/W4246212608
|
https://www.jneurology.com/articles/neuroimaging-in-cerebral-small-vessel-disease.pdf
|
English
| null | null |
Journal of neurology & neuromedicine
| 2,018
|
cc-by
| 5,830
|
ABSTRACT Article Info The diagnosis of cerebral small vessel disease (SVD) is difficult because there is
no consensus on clinical criteria and therefore, imaging is important for diagnosis. Most patients undergo brain imaging by computed tomography (CT), which is
able to detect ischemic strokes, hemorrhages and brain atrophy and may also
indicate white matter changes. Magnetic resonance imaging (MRI) remains the
key neuroimaging modality and is preferred to CT in vascular cognitive impairment
(VCI) because it has higher sensitivity and specificity for detecting pathological
changes. These modalities for imaging morphology permit to detect vascular
lesions traditionally attributed to VCI in subcortical areas of the brain, single
infarction or lacunes in strategic areas (thalamus or angular gyrus), or large cortical-
subcortical lesions reaching a critical threshold of tissue loss. In SVD multiple
punctuate or confluent lesions can be seen in the white matter by MRI and were
called leukoaraiosis. Another major neuroimaging finding of small vessel disease
in VCI are microhemorrhages. However, while CT and MRI are able to detect
morphologic lesions, these modalities cannot determine functional consequences
of the underlying pathological changes. © 2018 Heiss WD. This article is distributed under the terms of
the Creative Commons Attribution 4.0 International License Keywords:
Cerebral small vessel disease
SVD
Vascular cognitive impairment
Vascular dementia
Neuroimaging
MRI
CT
PET Positron emission tomography (PET) can support the clinical diagnosis by
visualizing cerebral functions in typically affected brain regions. In SVD, Fluor-
Deoxy-Glucose (FDG)-PET can clearly differentiate scattered areas of focal cortical
and subcortical hypometabolism that differ from the typical metabolic pattern seen
in Alzheimer Dementia (AD) with marked hypometabolism affecting the association
areas. Additional PET tracers can further support the diagnosis of a type of dementia
and also yield information on the underlying pathophysiology. Neuroimaging in Cerebral Small Vessel Disease
Wolf-Dieter Heiss1
1Max Planck Institute for Metabolism Research, Cologne, Germany Article Info
Article Notes
Received: February 06, 2018
Accepted: March 07, 2018
*Correspondence:
Dr. Wolf-Dieter Heiss, MD
Max Planck Institute for Metabolism Research
Gleueler Str. 50, D-50931 Cologne, Germany; Telephone: +49-
221-4726-220,
Email: wdh@sf.mpg.de
© 2018 Heiss WD. This article is distributed under the terms of
the Creative Commons Attribution 4.0 International License
Keywords:
Cerebral small vessel disease
SVD
Vascular cognitive impairment
Vascular dementia
Neuroimaging
MRI
CT
PET Article Info
Article Notes
Received: February 06, 2018
Accepted: March 07, 2018
*Correspondence:
Dr. Wolf-Dieter Heiss, MD
Max Planck Institute for Metabolism Research
Gleueler Str. 50, D-50931 Cologne, Germany; Telephone: +49-
221-4726-220,
Email: wdh@sf.mpg.de
© 2018 Heiss WD. This article is distributed under the terms of
the Creative Commons Attribution 4.0 International License
Keywords:
Cerebral small vessel disease
SVD
Vascular cognitive impairment
Vascular dementia
Neuroimaging
MRI
CT
PET Heiss WD. J Neurol Neuromedicine (2018) 3(2): 1-7 Heiss WD. J Neurol Neuromedicine (2018) 3(2): 1-7 www.jneurology.com www.jneurology.com Mini review Open Access Neuroimaging in Cerebral Small Vessel Disease
Wolf-Dieter Heiss1
1Max Planck Institute for Metabolism Research, Cologne, Germany Introduction Standards for neuroimaging with a widely
accepted terminology permitting comparison of findings
between centers have been recommended (STandards for
ReportIng Vascular changes on Neuroimaging, STRIVE) 24. Numerous studies identified MRI markers of small vessel
disease (SVD) (lacunes, white matter hyperintensities,
cerebral microbleeds, silent infarcts, white matter changes,
global cerebral atrophy, medial-temporal lobe atrophy) as
determinants of VaD 12, 25-27. Vascular lesions traditionally
attributed to VaD comprise subcortical areas of the brain,
especially sub-frontal white matter circuits, strategic areas
of single infarction such as the dominant thalamus or
angular gyrus, deep frontal areas and the left hemisphere,
and bilateral brain infarcts or volume-driven cortical-
subcortical infarctions reaching a critical threshold
of tissue loss or injury 5, 28. Recently, enlargements of
perivascular spaces were identified as MRI markers
of small vessel disease. These are associated with the
pathogenesis of vascular-related cognitive impairment
in older individuals29. The burden of SVD is increased in
systemic lupus erythematosus 30 and – as the risk of stroke
– in type 2 diabetes 31. Cerebral small vessel disease (SVD) is a condition
resulting from damage to the cerebral microcirculation. It
causes incomplete or complete infarcts in the white matter
or in subcortical gray matter nuclei 10-13, that are usually
clinically `silent´. Advanced SVD is characterized by white
matter hyperintensities (WMH), enlarged perivascular
spaces (PVS), lacunes, microbleeds and cerebral atrophy 14. These abnormalities are seen in up to 10% of persons in the
7th decade and in above 85% in their 9th decade. Lacunes
must be differentiated from perivascular Virchow-Robin
spaces. Lacunar strokes are small complete infarcts (2 to
15 mm) 15, 16. When located in the caudate head, anterior
thalamus, or the mamillothalamic tract 17 lacunae can
cause significant cognitive and/or behavioral dysfunction
due to the extended functional deafferentation of the
cortical areas. Since clinical signs and symptoms are often
insufficient to allow for a final diagnosis and usually cannot
differentiate among the various etiologies, neuroimaging
plays an important role in the management of patients
with impaired cognition. Neuroimaging is also relevant for
the detection of sporadic SVD 18. This review will concentrate on the importance of
imaging procedures for the diagnosis of SVD as a cause of
VCI. Additionally, it will describe the value of molecular
and functional imaging for the detection of the relationship
of morphological damage and cognitive impairment and
of the differentiation between vascular and degenerative
causes of dementia. Introduction Vascular etiologies are among the most common causes of dementia,
but the numbers vary considerably according to the different criteria
used for vascular cognitive impairment (VCI)1, 2. In the Rochester
Epidemiology Project of 419 old demented patients, the post mortem
diagnosis of AD was established in 51 %, of pure vascular dementia in
13 %, and of mixed vascular-Alzheimer dementia in 12 % of patients,
with “other” diagnosis in the remaining patients 3. According to a
controlled neuropathological study, pure vascular dementia (VaD) is
responsible for 8–10 %, Alzheimer’s disease (AD) for 60–70 %, and
dementia with Lewy bodies (DLB) for 10–25 % of dementia cases 4, 5,
Furthermore, it is evident from autopsy studies that many patients
have mixed dementias 6, often vascular disease with other conditions 5. Old criteria for VaD only included multi-infarct dementia 7 or dementia
resulting from the cumulative effects of several clinically significant
strokes, but the current criteria consider multi-infarct dementia as
only one of several subtypes of VaD, including single-stroke dementia
and small vessel disease. The three main neuroimaging patterns in VaD
are large vessels strokes (macroangiopathy, arteriosclerosis), small Page 1 of 7 Page 1 of 7 Heiss WD. J Neurol Neuromedicine (2018) 3(2): 1-7 Journal of Neurology & Neuromedicine vessel
disease
(microangiopathy,
arteriolosclerosis),
and microhemorrhages. Single large territorial strokes,
especially in the middle cerebral artery (MCA) territory
of the dominant hemisphere, or multiple smaller strokes
in bilateral anterior cerebral artery (ACA) or posterior
cerebral artery (PCA) territories, cause dementia in ∼30%
of stroke survivors 5, 8. Single smaller strokes can also
cause significant cognitive dysfunction when occurring
in particular locations, such as the watershed territories,
including the bilateral superior frontal gyrus or bilateral
orbitofrontal (ACA/MCA), angular gyrus (ACA/MCA/PCA),
temporo-occipital junction, and inferior temporal gyrus
(MCA/PCA) 9. swelling, hypodensity and hyperdense vessels) and old
stroke lesions. Furthermore, the presence and severity
of white matter lesions (WMLs) and brain atrophy can
also be readily determined from CT brain scans - features
which may predict subsequent cognitive impairment and
dementia. There is a very good agreement between brain
atrophy and presence of moderate-severe white matter
lesions on CT and MRI measures19, 20. Magnetic resonance imaging (MRI) remains the
key neuroimaging modality in VaD (review in21, 22). If not
contraindicated, MRI, rather than CT, is preferred for
research and routine clinical use because it has higher
sensitivity and specificity for detecting pathological
changes 23. Introduction Small vessel disease identified on MRI in the white
matter is called leukoaraiosis 32. Leukoaraiosis presents
as multiple punctuate or confluent lesions, but more often
as incomplete infarcts, and is commonly seen in healthy
elderly 33 and in subjects with migraine. The markers
of small vessel disease - white matter hyperintensities,
lacunes, dilated vascular spaces, microbleeds, and brain
volume - are related to decrease in regional cerebral
blood flow 34 and must be clearly defined to be reliably
used for the diagnosis of this vascular disorder and its
progression 25. Some studies have suggested that to assess
in single cases how much the lesion load affects cognition,
a threshold of 10 cm2 35 or 25% of total white matter 36
is required before VaD is detectable clinically. On FLAIR
images, incomplete infarcts present as hyperintensities,
whereas complete infarcts present as lacunae, which are
hypointense in relation to the brain and isointense to the
cerebrospinal fluid. Diffusion-weighted MRI is best suited Imaging morphologic substrates of Small Vessel Imaging morphologic substrates of Small Vessel
Disease Imaging morphologic substrates of Small Vessel
Disease Microhemorrhages are the third major neuroimaging
aspect of VaD, and in one study they were found in 65%
of VaD cases 40. While macrohemorrhages associated
with cognitive impairment (e.g., venous infarcts) can be
seen on conventional T1- and T2-weighted spin echo
images, microhemorrhages often cannot be seen in these
sequences, but can be detected accurately using T2*-
weighted gradient echo images. In many cases, it is likely
that microhemorrhages and white matter ischemic disease
are caused by systemic hypertension 41. Figure 1: Co-registered T2-weighted MRI and PET orthogonal
slices through the brain of a patient with vascular cognitive
impairment: T2-MRI shows typical periventricular and multiple
small white matter lesions, the PET images reveal the widespread
effect of these lesions on the glucose metabolism of the whole
cortex and the basal ganglia (Copyright W.-D. Heiss, MPI Cologne). Morphologic imaging indicates the extent and severity
of SVD, but the observed changes are not directly related
to functional or cognitive impairment and prognosis. In
one study 42 several MRI findings together with older
age and lower gait speed were identified as risk factors
associated with mortality. Functional effects of SVD can
only be detected by combining morphological imaging
with more complex technologies , e.g. magnetic resonance
spectroscopy for showing biochemical changes 43 and
functional MRI for analysis of cortical dysfunction 44. Advanced imaging techniques including molecular imaging
by positron emission tomography (PET) will help to
understand the mechanisms by which SVD causes VCI
and will improve diagnostic accuracy; they might reflect
disease progression and in the future might be useful for
development of therapies 45. cerebral glucose metabolism (rCMRGl) has shown a typical
metabolic pattern in patients with probable Alzheimer
Disease
(AD):
hypometabolism
in
temporoparietal
and frontal association areas, but relative recessing of
primary cortical areas, basal ganglia and cerebellum 46, 47. In VCI a different pattern is seen 48: In VCI FDG PET can
clearly differentiate scattered areas of focal cortical and
subcortical hypometabolism (Figure 1) that differ from
the typical metabolic pattern seen in AD with marked
hypometabolism affecting the association areas 49. In VaD patients 50 a significant reduction of rCMRglc in
comparison to normal patients was observed in widespread
cerebral regions (middle frontal cortex, temporoparietal
cortex, basal ganglia, cerebellum and brainstem). In
subcortical areas and primary sensorimotor cortex this
hypometabolism was more marked than in AD while the
association areas were less affected than in AD. Disease Neuroimaging provides important information on
neuroanatomical substrate of the disorder, plays an
important role in the diagnosis and adds to prediction
of VaD. Most acute stroke patients undergo computed
tomography (CT) brain imaging; thus studies using CT are
representative of the whole clinical population. In clinical
practice, CT is performed primarily to exclude haemorrhage
and some stroke mimics (such as brain tumours), and
can often demonstrate early signs of ischaemia (e.g. Page 2 of 7 Page 2 of 7 Heiss WD. J Neurol Neuromedicine (2018) 3(2): 1-7 Journal of Neurology & Neuromedicine to reveal surrogate markers of SVD progression 37. After stroke,
medial temporal lobe atrophy is rather related to cognitive
impairment than markers of small vessel disease 38. When
small vessel disease causes subcortical VaD, this is associated
with the pathology of Binswanger’s disease 39. Figure 1: Co-registered T2-weighted MRI and PET orthogonal
slices through the brain of a patient with vascular cognitive
impairment: T2-MRI shows typical periventricular and multiple
small white matter lesions, the PET images reveal the widespread
effect of these lesions on the glucose metabolism of the whole
cortex and the basal ganglia (Copyright W.-D. Heiss, MPI Cologne). A metabolic
ratio (rCMRglc of association areas divided by rCMRglc of
primary areas, basal ganglia, cerebellum and brainstem)
mainly reflecting the contrast between association areas
and subcortical regions was significantly lower in AD than
in VCI 51. Whereas it was not possible to identify a single
region that could discriminate between VCI and AD, the
composite pattern, as expressed in the metabolic ratio, was
significantly different. Considering that the VCI patients
in that study had mainly WMHs and small subcortical
infarcts, it suggests furthermore that even small infarcts
in combination with WMHs may contribute to cognitive
decline. Rather than the total volume of infarction, the
volume of functional tissue loss is more important, since
it also includes the effects of incompletely infarcted tissue
and morphologically intact but deafferented cortex (Figure
2). Subcortical ischemic vascular disease (SIVD) can be
distinguished from clinically probable AD by a more diffuse Figure 2: T1 and T2-weighted MRI and PET images in VCI caused
by multiple small infarcts, lacunes and widespread white matter
changes. The PET images show diffuse impairment of metabolism
in both hemispheres and also in basal ganglia, thalamus and
cerebellum (Copyright W.-D. Heiss, MPI Cologne). Imaging synaptic transmission and accumulation of
pathologic proteins Imaging synaptic transmission and accumulation of
pathologic proteins Molecular Imaging in the Diagnosis of Dementia due
to Small Vessel Disease Molecular Imaging in the Diagnosis of Dementia due
to Small Vessel Disease The diagnosis of vascular cognitive impairment (VCI) is
difficult because there is no consensus on clinical criteria. Additionally, cerebral arteriosclerosis frequently is present
in elderly patients and even small infarcts or white matter
lesions occur in elderly subjects without either cognitive
impairment or degenerative dementia. There is a tendency
to diagnose VCI on the basis of MRI, which has a high
sensitivity for white matter hyperintensities (WMHs),
which may be seen in normal elderly as well as those with
VCI. Pathological studies reveal a high incidence of both
vascular and degenerative pathology of the Alzheimer
type. This leads to diagnostic confusion when only the
MRI is used, and there is mixed pathologies. PET provides
additional information, which increases the diagnostic
certainty. Positron emission tomography can support the
clinical diagnosis by visualizing cerebral functions in
typically affected brain regions. PET of 18F-2-fluoro-2-
deoxy-D-glucose (FDG) for measurement of regional Page 3 of 7 Page 3 of 7 Journal of Neurology & Neuromedicine Heiss WD. J Neurol Neuromedicine (2018) 3(2): 1-7 cortex in corticobasal degeneration 62, the caudate nucleus
in Huntington’s chorea 63, the frontal cortex and midbrain
in progressive supranuclear palsy 64, pons and cerebellum
in olivopontocerebellar atrophy 65. It is also important
to note that depressive disorders may mimic cognitive
impairment; in these cases glucose metabolism does not
show regional abnormalities. Imaging synaptic transmission and accumulation of
pathologic proteins Additional PET tracers can further support the
diagnosis of a type of dementia and also yield information
on the underlying pathophysiology: Tracers permit the
study of selectively affected transmitter / receptor systems,
e.g. the cholinergic system in AD - significant reduction of
cholinergic activity in the cortex of AD patients and those
with MCI and early conversion to AD 66 - or the dopaminergic
system in LBD 67 and the detection of pathogenetic
depositions, e.g. amyloid and tau in AD 68 or inflammatory
reactions with microglia activations as in VCI. Especially
the imaging of accumulation of pathologic proteins is a
recent strategy to differentiate degenerative dementias:
Amyloid is a pathogenetic product in the development of
AD and its accumulation is a key finding in this disease. Its accumulation can be imaged by 11C labeled Pittsburgh
Compound B (PiB) 69 or by several newer 18F labeled tracers
70. Whereas only small amounts of amyloid can be detected
in the white matter in normal aging 71, accumulation is
visible in the frontal and temporo-parietal cortex in AD and
MCI 72. However, also in 20-30% of aged persons without
relevant cognitive impairment an increased accumulation
of amyloid can be detected 73, and the grade of amyloid
deposition as detected by PET is not related to the severity
of cognitive impairment 74. That means that amyloid
might be deposited in the brain eventually long before
cognitive impairment is recognized. Amyloid deposition
in combination with neuroinflammation as expressed in
microglia activation might play a role in the development
of post-stroke dementia 75. Figure 2: T1 and T2-weighted MRI and PET images in VCI caused
by multiple small infarcts, lacunes and widespread white matter
changes. The PET images show diffuse impairment of metabolism
in both hemispheres and also in basal ganglia, thalamus and
cerebellum (Copyright W.-D. Heiss, MPI Cologne). pattern of hypometabolism involving also the primary
cortices, basal ganglia, thalamus and cerebellum. Conclusion 7. Hachinski V, Iliff LD, Zilkha E, et al. Cerebral blood flow in dementia. ArchNeurol. 1975; 32: 632-637. Small vessel disease (SVD) denotes a group of diseases
that affect the small vessels of the brain, mostly due
to chronic hypertensive damage to small arteries and
arterioles. The diagnosis of SVD is difficult because there
is no consensus on clinical criteria. Clinical manifestations
include cognitive impairment and emotional disturbances. The initially observed mild neurocognitive disorder
usually is progressive and affects other domains such
as sensorimotor functions, coordination, language and
memory. Over time it can result in vascular dementia. SVD
is more frequent than previously thought and can now be
better detected due to progress in neuroimaging. 8. Guermazi A, Miaux Y, Rovira-Canellas A, et al. Neuroradiological
findings in vascular dementia. Neuroradiology. 2007; 49: 1-22. 9. Pohjasvaara T, Mantyla R, Salonen O, et al. MRI correlates of dementia
after first clinical ischemic stroke. J Neurol Sci. 2000; 181: 111-117. 10. Roman GC, Erkinjuntti T, Wallin A, et al. Subcortical ischaemic vascular
dementia. Lancet Neurology. 2002; 1: 426-436. 11. Wardlaw JM, Smith C, Dichgans M. Mechanisms of sporadic cerebral
small vessel disease: insights from neuroimaging. Lancet Neurol. 2013; 12: 483-497. 12. Norrving B. Evolving Concept of Small Vessel Disease through
Advanced Brain Imaging. J Stroke. 2015; 17: 94-100. 13. Shi Y, Wardlaw JM. Update on cerebral small vessel disease: a dynamic
whole-brain disease. Stroke Vasc Neurol. 2016; 1: 83-92. In
acute
cerebrovascular
disease,
computed
tomography is the first imaging procedure, as it can detect
ischemic strokes, hemorrhages and brain atrophy and
may also indicate white matter changes. MRI remains the
key neuroimaging modality in chronic vascular cognitive
impairment (VCI) because it has higher sensitivity and
specificity for detecting pathological changes. It permits
to detect vascular lesions traditionally attributed to SVD
in subcortical areas of the brain, lacunes in strategic
areas (thalamus or angular gyrus). Multiple punctuates
or confluent lesions can be seen in the white matter
by MRI and are called leukoaraiosis. Another major
neuroimaging finding of small vessel disease in VCI are
microhemorrhages. However, while computed tomography
and magnetic resonance imaging are able to detect
morphologic lesions, these modalities cannot determine
functional consequences of the underlying pathological
changes, which can be detected and quantitatively
assessed by PET. Additionally, pathological studies reveal a
high incidence of mixed dementias with both vascular and
degenerative pathology of the Alzheimer type . References 1. Rockwood K, Wentzel C, Hachinski V, et al. Prevalence and outcomes
of vascular cognitive impairment. Vascular Cognitive Impairment
Investigators of the Canadian Study of Health and Aging. Neurology. 2000; 54: 447-451. 2. De Reuck J, Deramecourt V, Cordonnier C, et al. The incidence of post-
mortem neurodegenerative and cerebrovascular pathology in mixed
dementia. J Neurol Sci. 2016; 366: 164-166. 3. Knopman DS, Parisi JE, Boeve BF, et al. Vascular dementia in a
population-based autopsy study. Arch Neurol. 2003; 60: 569-
575. 4. Jellinger KA, Attems J. Neuropathological evaluation of mixed
dementia. J Neurol Sci. 2007; 257: 80-87. 5. Jellinger KA. The enigma of vascular cognitive disorder and vascular
dementia. Acta Neuropathol. 2007; 113: 349-388. 6. Korczyn AD. Mixed dementia--the most common cause of dementia. Ann N Y Acad Sci. 2002;977:129-134. Differential diagnosis of dementias with FDG-PET All together PET studies may shed
light into the pathophysiological mechanisms responsible
for the disease in a single patient, repeated investigations
in the course may reflect progression and may help to
demonstrate efficiency in the develpment of new treatment
strategies. However, due to the scarcity of complete PET
installations including cyclotron and radiochemistry, PET
is mainly restricted to applications in research. With the
installation of more clinical PET cameras as satellites to a
central FDG producing unit - a concept, which is already
successful for imaging in oncology - more patients with
mild cognitive impairment could benefit from improved
diagnostic imaging. tau), to image synaptic transmission and receptor activity
is of special value for the differential diagnosis of different
types of dementia. All together PET studies may shed
light into the pathophysiological mechanisms responsible
for the disease in a single patient, repeated investigations
in the course may reflect progression and may help to
demonstrate efficiency in the develpment of new treatment
strategies. However, due to the scarcity of complete PET
installations including cyclotron and radiochemistry, PET
is mainly restricted to applications in research. With the
installation of more clinical PET cameras as satellites to a
central FDG producing unit - a concept, which is already
successful for imaging in oncology - more patients with
mild cognitive impairment could benefit from improved
diagnostic imaging. Differential diagnosis of dementias with FDG-PET Differential diagnosis of dementias with FDG-PET Alzheimer’s disease (AD) is characterized by regional
impairment of cerebral glucose metabolism in neocortical
association areas, whereas the primary visual and
sensorimotor cortex, basal ganglia, and cerebellum
are relatively well preserved 52. In a multicentre study
comprising 10 PET centers that employed an automated
voxel-based analysis of FDG PET images, the distinction
between controls and AD patients had 93% sensitivity
and 93% specificity 53. Significantly abnormal metabolism
in mild cognitive impairment (MCI) indicates a high risk
to develop dementia within the next two years. Reduced
neocortical glucose metabolism can probably be detected
with FDG PET in AD on average one year before onset of
subjective cognitive impairment 54, 55. A more specific pathologic protein produced in AD
is tau, and its deposition in the mesial temporal lobe is
an early marker of AD or MCI 76 and the amount of tau
detected in the cortex by selective PET-tracers is related to
the severity of cognitive impairment 77. These PET-tracers
also detect the primary pathological substrate in other
degenerative dementias (e.g. tau in FTD) 78 and permit the
differentiation between AD and VCI and other degenerative
dementias 79-82. Characteristic patterns of regional hypometabolism
are also seen in other degenerative dementias
56-60. Frontotemporal dementia (FTD) clinically characterized by
changes in personality and behavior, semantic deficits and
progressive aphasia can be identified by distinct frontal or
frontotemporal metabolic impairments that are typically
quite asymmetrically centered in the frontolateral cortex
and the anterior pole of the temporal lobe. Dementia
with Lewy bodies (LBD)
61, combining fluctuating
consciousness, Parkinsonian symptoms and impairment
of visual perception including hallucinations, shows
reduction of glucose metabolism in primary visual cortex
in addition to that in posterior association areas. Other
degenerative disorders show typical hypometabolism in
the specifically affected brain structures: the putamen and The unique potentials of PET in localizing and quantifying
metabolic changes in gray matter structures responsible
for functional/cognitive disturbances and caused by SVD
mainly affecting the white matter makes this technique the
preferred tool for studying patients with VCI; the additional
ability of PET to detect pathologic proteins (amyloid and Page 4 of 7 Page 4 of 7 Heiss WD. J Neurol Neuromedicine (2018) 3(2): 1-7 Journal of Neurology & Neuromedicine tau), to image synaptic transmission and receptor activity
is of special value for the differential diagnosis of different
types of dementia. Conclusion J Cereb Blood Flow Metab. 2016; 36: 1319-1337. 43. Schaefer A, Quinque EM, Kipping JA, et al. Early small vessel disease
affects frontoparietal and cerebellar hubs in close correlation with
clinical symptoms--a resting-state fMRI study. J Cereb Blood Flow
Metab. 2014; 34: 1091-1095. 25. Salamon N. Neuroimaging of cerebral small vessel disease. Brain
Pathol. 2014; 24: 519-524. 26. Shibuya M, Leite CDC, Lucato LT. Neuroimaging in cerebral small
vessel disease: Update and new concepts. Dement Neuropsychol. 2017; 11: 336-342. 44. Banerjee G, Wilson D, Jager HR, et al. Novel imaging techniques in
cerebral small vessel diseases and vascular cognitive impairment. Biochim Biophys Acta. 2016; 1862: 926-938. 27. Peres R, De Guio F, Chabriat H, et al. Alterations of the cerebral cortex
in sporadic small vessel disease: A systematic review of in vivo MRI
data. J Cereb Blood Flow Metab. 2016; 36: 681-695. 45. Foster NL, Chase TN, Mansi L, et al. Cortical abnormalities in
Alzheimer’s disease. AnnNeurol. 1984; 16: 649-654 46. Minoshima S, Giordani B, Berent S, et al. Metabolic reduction in the
posterior cingulate cortex in very early Alzheimer’s disease. Ann
Neurol. 1997; 42: 85-94. 28. Ding J, Sigurethsson S, Jonsson PV, et al. Large Perivascular Spaces
Visible on Magnetic Resonance Imaging, Cerebral Small Vessel Disease
Progression, and Risk of Dementia: The Age, Gene/Environment
Susceptibility-Reykjavik Study. JAMA Neurol. 2017; 74: 1105-1112. 47. Heiss WD, Zimmermann-Meinzingen S. PET imaging in the differential
diagnosis of vascular dementia. J Neurol Sci. 2012; 322: 268-273. 29. Wiseman SJ, Bastin ME, Jardine CL, et al. Cerebral Small Vessel Disease
Burden Is Increased in Systemic Lupus Erythematosus. Stroke. 2016;
47: 2722-2728. 48. Benson DF, Kuhl DE, Hawkins RA, et al. The fluorodeoxyglucose 18F
scan in Alzheimer’s disease and multi-infarct dementia. Arch Neurol. 1983; 40: 711-714. 30. Umemura T, Kawamura T, Hotta N. Pathogenesis and neuroimaging of
cerebral large and small vessel disease in type 2 diabetes: A possible
link between cerebral and retinal microvascular abnormalities. J
Diabetes Investig. 2017; 8: 134-148. 49. Mielke R, Herholz K, Grond M, et al. Severity of vascular dementia
is related to volume of metabolically impaired tissue. Archives of
Neurology. 1992; 49: 909-913. 50. Mielke R, Heiss WD. Positron emission tomography for diagnosis of
Alzheimer’s disease and vascular dementia. JNeural TransmSuppl. 1998; 53: 237-250. 31. Hachinski VC, Potter P, Merskey H. Leuko-araiosis. ArchNeurol. 1987;
44: 21-23. 32. de Leeuw FE, de Groot JC, Achten E, et al. Conclusion This leads
to diagnostic confusion when only MRI is used. That means
that molecular imaging by PET may play an important role
in the differentiation of vascular and degenerative cognitive
impairment. 14. Blair GW, Hernandez MV, Thrippleton MJ, et al. Advanced
Neuroimaging of Cerebral Small Vessel Disease. Curr Treat Options
Cardiovasc Med. 2017; 19: 56. 15. Debette S, Markus HS. The clinical importance of white matter
hyperintensities on brain magnetic resonance imaging: systematic
review and meta-analysis. BMJ. 2010; 341: c3666. 16. Fisher CM. The arterial lesions underlying lacunes. Acta Neuropathol. 1968; 12: 1-15. 17. Carrera E, Bogousslavsky J. The thalamus and behavior: effects of
anatomically distinct strokes. Neurology. 2006; 66: 1817-1823. 18. Charidimou A, Pantoni L, Love S. The concept of sporadic cerebral
small vessel disease: A road map on key definitions and current
concepts. Int J Stroke. 2016; 11: 6-18. 19. Wattjes MP, Henneman WJ, van der Flier WM, et al. Diagnostic imaging
of patients in a memory clinic: comparison of MR imaging and
64-detector row CT. Radiology. 2009; 253: 174-183. 20. Wahlund LO, Barkhof F, Fazekas F, et al. A new rating scale for age-
related white matter changes applicable to MRI and CT. Stroke. 2001;
32: 1318-1322. 21. Vitali P, Migliaccio R, Agosta F, et al. Vessel Disease With MRI. Stroke. 2017; 48: 3175-3182. 22. Brainin M, Tuomilehto J, Heiss WD, et al. Post-stroke cognitive decline:
an update and perspectives for clinical research. Eur J Neurol. 2015;
22: 229-238, e213-226. 23. Wardlaw JM, Smith EE, Biessels GJ, et al. Neuroimaging standards for 23. Wardlaw JM, Smith EE, Biessels GJ, et al. Neuroimaging standards for Page 5 of 7 Page 5 of 7 Heiss WD. J Neurol Neuromedicine (2018) 3(2): 1-7 Journal of Neurology & Neuromedicine research into small vessel disease and its contribution to ageing and
neurodegeneration. Lancet Neurol. 2013; 12: 822-838. research into small vessel disease and its contribution to ageing and
neurodegeneration. Lancet Neurol. 2013; 12: 822-838. magnetic resonance spectroscopy of human brain: applications to
normal white matter, chronic infarction, and MRI white matter signal
hyperintensities. Magnetic Resonance in Medicine. 1992; 26: 313-
327. magnetic resonance spectroscopy of human brain: applications to
normal white matter, chronic infarction, and MRI white matter signal
hyperintensities. Magnetic Resonance in Medicine. 1992; 26: 313-
327. 24. De Guio F, Jouvent E, Biessels GJ, et al. Reproducibility and variability
of quantitative magnetic resonance imaging markers in cerebral small
vessel disease. Conclusion Prevalence of cerebral
white matter lesions in elderly people: a population based magnetic
resonance imaging study. The Rotterdam Scan Study. J Neurol
Neurosurg Psychiatry. 2001; 70: 9-14. 51. Herholz K. PET studies in dementia. Ann Nucl Med. 2003; 17: 79-89. 52. Herholz K, Salmon E, Perani D, et al. Discrimination between Alzheimer
dementia and controls by automated analysis of multicenter FDG PET. Neuroimage. 2002; 17: 302-326. 33. Shi Y, Thrippleton MJ, Makin SD, et al. Cerebral blood flow in small
vessel disease: A systematic review and meta-analysis. J Cereb Blood
Flow Metab. 2016; 36: 1653-1667. 53. Herholz K, Nordberg A, Salmon E, et al. Impairment of neocortical
metabolism
predicts
progression
in
Alzheimer’s
disease. DementGeriatrCognDisord. 1999; 10: 494-504. 34. Boone KB, Miller BL, Lesser IM, et al. Neuropsychological correlates
of white-matter lesions in healthy elderly subjects. A threshold effect. Arch Neurol. 1992; 49: 549-554. 54. Chetelat G, Desgranges B, de lSV, et al. Mild cognitive impairment: Can
FDG-PET predict who is to rapidly convert to Alzheimer’s disease. Neurology. 2003; 60: 1374-1377. 35. van Straaten EC, Scheltens P, Knol DL, et al. Operational definitions
for the NINDS-AIREN criteria for vascular dementia: an interobserver
study. Stroke. 2003; 34: 1907-1912. 55. Bohnen NI, Djang DS, Herholz K, et al. Effectiveness and safety of
18F-FDG PET in the evaluation of dementia: a review of the recent
literature. J Nucl Med. 2012; 53: 59-71. 36. Lyoubi-Idrissi AL, Jouvent E, Poupon C, et al. Diffusion magnetic
resonance imaging in cerebral small vessel disease. Rev Neurol
(Paris). 2017; 173: 201-210. 56. Duara R, Barker W, Luis CA. Frontotemporal dementia and Alzheimer’s
disease: differential diagnosis. Dement Geriatr Cogn Disord. 1999; 10
Suppl 1: 37-42. 37. Arba F, Quinn T, Hankey GJ, et al. Cerebral small vessel disease, medial
temporal lobe atrophy and cognitive status in patients with ischaemic
stroke and transient ischaemic attack. Eur J Neurol. 2017; 24: 276-
282. 57. Herholz K, Carter SF, Jones M. Positron emission tomography imaging
in dementia. Br J Radiol. 2007; 80 Spec No 2: S160-167. 58. Tripathi M, Tripathi M, Damle N, et al. Differential diagnosis of
neurodegenerative dementias using metabolic phenotypes on F-18
FDG PET/CT. Neuroradiol J. 2014; 27: 13-21. 38. Roman GC. Senile dementia of the Binswanger type. A vascular form
of dementia in the elderly. JAMA. 1987; 258: 1782-1788. 39. Cordonnier C, van der Flier WM, Sluimer JD, et al. Conclusion Prevalence and
severity of microbleeds in a memory clinic setting. Neurology. 2006;
66: 1356-1360. 59. Ishii K. PET approaches for diagnosis of dementia. AJNR Am J
Neuroradiol. 2014; 35: 2030-2038. 60. Bohnen NI, Muller M, Frey KA. Molecular Imaging and Updated
Diagnostic Criteria in Lewy Body Dementias. Curr Neurol Neurosci
Rep. 2017; 17: 73. 40. Koennecke HC. Cerebral microbleeds on MRI: prevalence, associations,
and potential clinical implications. Neurology. 2006; 66: 165-171. 41. van der Holst HM, van Uden IW, Tuladhar AM, et al. Factors Associated
With 8-Year Mortality in Older Patients With Cerebral Small Vessel
Disease: The Radboud University Nijmegen Diffusion Tensor and
Magnetic Resonance Cohort (RUN DMC) Study. JAMA Neurol. 2016;
73: 402-409. 61. Murgai AA, Jog MS. Neurophysiology and neurochemistry of
corticobasal syndrome. J Neurol. 2018. 62. Ciarmiello A, Giovacchini G, Giovannini E, et al. Molecular Imaging of
Huntington’s Disease. J Cell Physiol. 2017;232:1988-1993. 42. Sappey-Marinier D, Calabrese G, Hetherington HP, et al. Proton 63. Whitwell JL, Hoglinger GU, Antonini A, et al. Radiological biomarkers Page 6 of 7 Page 6 of 7 Heiss WD. J Neurol Neuromedicine (2018) 3(2): 1-7 Journal of Neurology & Neuromedicine for diagnosis in PSP: Where are we and where do we need to be? Mov
Disord. 2017; 32: 955-971. for diagnosis in PSP: Where are we and where do we need to be? Mov
Disord. 2017; 32: 955-971. 73. Yotten RA, Doshi J, Clark V, et al. Memory decline shows stronger
associations with estimated spatial patterns of amyloid deposition
progression than total amyloid burden. Neurobiol Aging. 2013; in
press. 64. Gilman S. Functional imaging with positron emission tomography in
multiple system atrophy. J Neural Transm (Vienna). 2005; 112: 1647-
1655. 74. Thiel A, Cechetto DF, Heiss WD, et al. Amyloid burden,
neuroinflammation, and links to cognitive decline after ischemic
stroke. Stroke. 2014; 45: 2825-2829. 65. Herholz K, Weisenbach S, Kalbe E, et al. Cerebral acetylcholine esterase
activity in mild cognitive impairment. Neuroreport. 2005;16:1431-1434. 75. Maruyama M, Shimada H, Suhara T, et al. Imaging of tau pathology
in a tauopathy mouse model and in Alzheimer patients compared to
normal controls. Neuron. 2013; 79: 1094-1108. 66. Hilker R, Thomas AV, Klein JC, et al. Dementia in Parkinson disease:
functional imaging of cholinergic and dopaminergic pathways. Neurology. 2005; 65: 1716-1722. 76. Small GW, Bookheimer SY, Thompson PM, et al. Current and future
uses of neuroimaging for cognitively impaired patients. Lancet
Neurol. 2008; 7: 161-172. 67. Conclusion Braak H, Braak E. Neuropathological staging of Alzheimer related
changes. Acta Neuropathol. 1991; 82: 239-259. 68. Klunk WE, Engler H, Nordberg A, et al. Imaging brain amyloid in
Alzheimer’s disease with Pittsburgh Compound-B. AnnNeurol. 2004;
55: 306-319. 77. Spillantini MG, Goedert M. Tau pathology and neurodegeneration. Lancet Neurol. 2013; 12: 609-622. 78. Scholl M, Lockhart SN, Schonhaut DR, et al. PET Imaging of Tau
Deposition in the Aging Human Brain. Neuron. 2016; 89: 971-982. 69. Villemagne VL, Mulligan RS, Pejoska S, et al. Comparison of 11C-PiB
and 18F-florbetaben for Abeta imaging in ageing and Alzheimer’s
disease. Eur J Nucl Med Mol Imaging. 2012; 39: 983-989. 79. Sepulcre J, Schultz AP, Sabuncu M, et al. In Vivo Tau, Amyloid, and Gray
Matter Profiles in the Aging Brain. J Neurosci. 2016; 36: 7364-7374. 70. Aizenstein HJ, Nebes RD, Saxton JA, et al. Frequent amyloid deposition
without significant cognitive impairment among the elderly. Arch
Neurol. 2008; 65: 1509-1517. 80. Drzezga A, Barthel H, Minoshima S, et al. Potential Clinical Applications
of PET/MR Imaging in Neurodegenerative Diseases. J Nucl Med. 2014;
55: 47S-55S. 71. Barthel H, Schroeter ML, Hoffmann KT, et al. PET/MR in dementia and
other neurodegenerative diseases. Semin Nucl Med. 2015; 45: 224-233. 81. Chiotis K, Saint-Aubert L, Savitcheva I, et al. Imaging in-vivo tau
pathology in Alzheimer’s disease with THK5317 PET in a multimodal
paradigm. Eur J Nucl Med Mol Imaging. 2016; 43: 1686-1699. 72. Herholz K, Ebmeier K. Clinical amyloid imaging in Alzheimer’s disease. Lancet Neurol. 2011; 10: 667-670. Page 7 of 7 Page 7 of 7
|
https://openalex.org/W1567264982
|
https://genomebiology.biomedcentral.com/track/pdf/10.1186/gb-2000-1-1-reports243
|
English
| null |
Variations on a gene
|
Genome biology
| 2,000
|
cc-by
| 883
|
PublisherInfo
PublisherName
:
BioMed Central
PublisherLocation
:
London
PublisherImprintName
:
BioMed Central PublisherInfo
PublisherName
:
BioMed Central
PublisherLocation
:
London
PublisherImprintName
:
BioMed Central PublisherInfo
PublisherName
:
BioMed Central
PublisherLocation
:
London
PublisherImprintName
:
BioMed Central Content Launched in September 1998, dbSNP is the central repository for data on single-nucleotide
polymorphisms (SNPs), the most common form of sequence variation in human populations. It is hoped
that establishing a large collection of mapped SNPs will accelerate the identification of disease genes by
association studies. Such studies aim to discover statistical associations between genetic variations and
heritable diseases. At the most recent update, dbSNP contained data for 26,397 SNPs but this number is
expected to increase to several hundred thousand over the next few years. The database contains details
of the sequences in which the SNP is found, mapping information, the populations and number of
chromosomes sampled, estimated heterozygosities, and PCR assay primers and protocols. Each unique
SNP is assigned a reference SNP ID, or 'rs ID'. To reduce redundancy in the database, subsequent
submissions that map to locations identical to previously submitted SNPs will be linked to the existing
reference SNP record. New data may be submitted to dbSNP by e-mail as explained at the site. The
database may be searched by simple text queries of various database fields. For example, a SNP may be
retrieved by its rs ID, the GenBank accession numbers of the sequences within which it occurs or the
laboratory that submitted it. Perhaps the most useful search method provided is BLAST searching of
SNP flanking sequences - the identification of SNPs plus their surrounding sequences that significantly
match a sequence of interest. Variations on a gene g
ArticleInfo
ArticleID
:
3617
ArticleDOI
:
10.1186/gb-2000-1-1-reports243
ArticleCitationID
:
reports243
ArticleSequenceNumber
:
108
ArticleCategory
:
Web report
ArticleFirstPage
:
1
ArticleLastPage
:
4
ArticleHistory
:
RegistrationDate : 2000–3–9
Received
: 2000–3–9
OnlineDate
: 2000–4–27
ArticleCopyright
:
BioMed Central Ltd2000
ArticleGrants
:
ArticleContext
:
130591111 Colin Semple
Abstract
Launched in September 1998, dbSNP is the central repository for data on single-nucleotide
polymorphisms (SNPs), the most common form of sequence variation in human populations. Colin Semple Abstract Abstract
Launched in September 1998, dbSNP is the central repository for data on single-nucleotide
polymorphisms (SNPs), the most common form of sequence variation in human populations. Launched in September 1998, dbSNP is the central repository for data on single-nucleotide
polymorphisms (SNPs), the most common form of sequence variation in human populations. Timeliness dbSNP is updated erratically every few months with newly submitted variations. Submissions from
large, ongoing projects are expected to expand the database by thousands of new SNPs at a time at
irregular intervals over the next few years. Best feature One very useful feature of dbSNP is its integration with NCBI's LocusLink, which summarizes the
sequence and mapping data available for known loci, including information on alternative gene names,
expression (via the NCBI UniGene database) and gene products. Given the GenBank accession number
of an mRNA, one can retrieve the corresponding LocusLink entry and view all the SNPs associated with
all the sequences in that entry, regardless of whether these SNPs are present in the starting mRNA
sequence. For example it is possible to find SNPs present in the untranslated regions of mRNAs when
all you begin with is the coding sequence accession number. Eventually, as LocusLink integrates
genomic data from the Human Genome Project, it should be possible to find intronic SNPs in the same
way. Navigation The site is well documented, with links from SNP records to other NCBI resources such as GenBank
and LocusLink. It is not possible, however, to bookmark individual SNP records. The design of the site
occasionally tends towards the labyrinthine; the pages on submission make the process seem quite
complex at first sight. The new interfaces for form-based data submission and searching that are
currently under development will undoubtedly address such shortcomings. Worst feature Caution should be taken with any SNPs retrieved from the database because of the presence of non-
validated SNPs identified computationally by groups such as the Cancer genome anatomy project
genetic annotation initiative (CGAP-GAI). Such SNPs are annotated as 'candidates' and have not been
verified empirically. A proportion (around 8% of the CGAP-GAI candidate SNPs) of the candidate
SNPs are expected to be artifactual. UniGene Human genic bi-allelic sequences Wish list In positional cloning projects the interest is invariably in a region of the genome rather than a specific
gene. Consequently, it would be useful to be able to retrieve SNPs by map location. This kind of search
is currently under development. References 1. dbSNP: A database of human single nucleotide polymorphisms. 1. dbSNP: A database of human single nucleotide polymorphisms. Related websites The SNP consortium is a non-profit foundation set up by the Wellcome Trust and various
pharmaceutical companies to develop up to 300,000 SNPs distributed evenly throughout the human
genome and to make the information related to these SNPs publicly available. The SNP consortium site
provides searchable access to quarterly SNP data releases; the data are also submitted to dbSNP. Human
genic bi-allelic sequences (HGBase) is a database of intragenic (promoter to end of transcription)
sequence polymorphisms including SNPs and intron variations. It contains a smaller number of
variations than dbSNP. Table of links dbSNP: A database of human single nucleotide polymorphisms
|
https://openalex.org/W1548001109
|
https://bmcinfectdis.biomedcentral.com/counter/pdf/10.1186/1471-2334-1-11
|
English
| null |
Clinical utility of a nested nucleic acid amplification format in comparison to viral culture for the diagnosis of mucosal herpes simplex infection in a genitourinary medicine setting
|
BMC infectious diseases
| 2,001
|
cc-by
| 4,018
|
BioMed Central BioMed Central BioMed Central BMC Infectious Diseases
2001,
1Research article Address: 1Regional Virus Laboratory, Royal Hospitals Trust, BT12 6BA, Belfast, UK and 2Department of Genitourinary Medicine, Royal
Hospitals Trust, BT12 6BA, Belfast, UK aboratory, Royal Hospitals Trust, BT12 6BA, Belfast, UK and 2Department of Genitourinary Medicine, Royal
Belfast, UK E-mail: Peter V Coyle* - peter.coyle@bll.n-i.nhs.uk; Hugh J O'Neill - hugh.oneill@bll.n-i.nhs.uk;
Conall McCaughey - conall.mccaughey@bll.n-i.nhs.uk; Dorothy E Wyatt - dorothy.wyatt@bll.n-i.nhs.uk;
Michael O McBride - michael.mcbride@royalhospitals.n-i.nhs.uk *Corresponding author Received: 12 June 2001
Accepted: 21 August 2001 This article is available from: http://www.biomedcentral.com/1471-2334/1/11 © 2001 Coyle et al; licensee BioMed Central Ltd. Verbatim copying and redistribution of this article are permitted in any medium for any non-com-
mercial purpose, provided this notice is preserved along with the article's original URL. For commercial use, contact info@biomedcentral.com © 2001 Coyle et al; licensee BioMed Central Ltd. Verbatim copying and redistribution of this article are permitted in any
mercial purpose, provided this notice is preserved along with the article's original URL. For commercial use, contact info Specimens p
Swabs were taken from appropriate oral (2) and ano-
genital sites (88) including penile, vulval, vaginal and
anal specimens. The swabs were sent to the laboratory in
2 ml of viral transport medium consisting of phosphate
buffered saline (PBS) pH 7.1, bovine serum albumin 7.5
µg/ml, penicillin G sodium 10 units/ml, streptomycin
sulphate 10 µg/ml and amphotericin B 0.25 µg/ml. Each
specimen was vortexed for 15 seconds on receipt in the
laboratory to resuspend the cellular content, but other-
wise received no further pre-treatment. A 50 µl volume
was removed for virus culture and multiplex nPCR. A 1.5
ml volume of the remainder of the specimen was centri-
fuged in a screw-capped polypropylene tube (Sarstedt) at
15000 g for 10 minutes to assess the specimen cell con-
tent. Cell pellets of less than 2 mm in diameter were re-
garded as sub-optimal. g
Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2)
infections are among the commonest clinically encoun-
tered in medical practice and worldwide are the main
causes of oral and genital ulceration [1–4]. HSV-2 is nor-
mally linked to genital ulceration but increasingly HSV-1
is also encountered and in Northern Ireland has become
the predominant genital type recovered from women [5]. It is recognised that genital infections with either virus
present with painful muco-cutaneous lesions in 95% of
primary cases, and in 84% with non-primary episodes;
constitutional upset accompanies 79% and 43% of pri-
mary and non-primary episodes respectively [6]. Al-
though culture remains the gold standard for the direct
diagnosis of HSV associated mucosal ulceration [7], in-
creasingly HSV specific nucleic acid amplification test
(NAT) assays are being recognised to improve test sensi-
tivity [2,8,9]. Real-time assays are also becoming availa-
ble [10–12] but are currently beyond the price range of
many laboratories. We have previously reported a multi-
plex nested polymerase chain reaction (nPCR) assay for
HSV detection, with significantly improved sensitivity
when compared to standard virus culture [13]. However
in routine practice there are two main concerns sur-
rounding the use of a nested NAT format. First there is
concern that the high sensitivity will result in the detec-
tion of clinically non-significant levels of infection, spe-
cifically asymptomatic shedding in the case of HSV. Secondly the assays are thought susceptible to generat-
ing false positive results [7,14–16] and therefore will
have an unacceptable level of specificity for routine prac-
tice. Virus culture
i
l Virus culture was undertaken as reported previously
[17]. Suspensions of 4 cell lines consisting of primary
rhesus monkey kidney (CPHL, Porton Down, England),
E6-vero (ATCC CRL1586), RD (ATCC CCL136) and HEp-
2 (ATCC CCL23) were used. Four wells of 96 well U-bot-
tomed tissue culture plates (Becton Dickinson, Oxford,
England) were each inoculated with 10 µl of the speci-
men; all of the wells contained 90 µl of serum free Eagle's
minimum essential medium (MEM) (Bio-Whittaker UK
Ltd, Wokingham, England). Log dilutions from each in-
oculated well were made to 3 adjacent wells (in a column
of 4) by the sequential transfer of 10 µl volumes. Each of
the 4 cell suspensions (25 µl), in MEM with 10% fetal calf
serum (Life Technologies, Paisley, Scotland, UK), was
added to its corresponding column. The plates were in-
cubated in a sealed box in a 5% CO2 atmosphere at 37°C
for 7 days and read daily for the presence of cytopathic
effect (CPE). Cells showing CPE were harvested and
screened by the Syva MicroTrak HSV-1 and HSV-2 cul-
ture confirmation system (Behring, Milton Keynes, Eng-
land). Abstract Background: Nested nucleic acid amplification tests are often thought too sensitive or prone to
generatingfalse positive results for routine use. The current study investigated the specificity and
clinicalutility of a routine multiplex nested assay for mucosal herpetic infections. Methods: Ninety patients, categorised into those clinically diagnosed to (a) have and (b) not
haveherpetic infection, were enrolled. Swabs from oral and ano-genital sites were assayed by
thenested assay and culture and the results assessed against clinical evaluation for
diagnosingherpetic infections; cell content was also recorded. Results: Twenty-six and 64 patients were thought to (a) have and (b) not have mucosal
herpeticinfection. Taking the clinical evaluation as indicating the presence of herpetic infection,
thenested polymerase chain reaction and culture had respective sensitivities of 19/26 (73%) and12/
26 (46%) (Χ2 p = 0.02). There was no significant difference in specificities between nPCR62/64
(97%) and culture 63/64 (98%) (Χ2 p = 1.0). Cell content was important for viraldetection by nPCR
(Χ2 p = 0.07) but not culture. Nesting was found necessary for sensitivity anddid not reduce
specificity. Assay under-performance appeared related to sub-optimal cellcontent (20%) but may
have reflected clinical over-diagnosis. The results suggest the need forvalidating specimen cell
quality. Conclusions: This study questions the value of routine laboratory confirmation of mucosal
herpetic infection. The adoption of a more discriminatory usage of laboratory diagnostic facilities
for genital herpetic infection, taking account of cell content, and restricting it to those cases where
it actually affects patient management, may be warranted. http://www.biomedcentral.com/1471-2334/1/11 http://www.biomedcentral.com/1471-2334/1/11 BMC Infectious Diseases 2001, 1:11 http://www.biomedcentral.com/1471-2334/1/11 http://www.biomedcentral.com/1471-2334/1/11 Specimens For these reasons we felt it necessary to validate the
clinical performance of the multiplex nPCR assay we
routinely use for HSV diagnosis. This study utilised the
predictive value of clinical evaluation for diagnosing
muco-cutaneous HSV infection by experienced medical
personnel and was based in a genitourinary medicine
clinic. 1The thermal cycler was held at 94°C for 3 min before cycling began
to facilitate the transfer of specimens, held on ice, for a hot start pro-
cedure. Patients and specimens Twenty-six of the 90 patients seen were thought on clin-
ical grounds to have mucosal herpes while the remaining
64 were assessed as having non-specific lesions incon-
sistent with herpetic involvement. All patient specimens
sent to the laboratory were received within 24 hours. Of
the specimens received, 18/90 (20%) were found to be
sub-optimal on the basis of a pellet size less than 2 mm
in diameter after centrifugation. Two laboratory confirmed cases, clinically evaluated to
lack evidence of herpetic infection, implied inappropri-
ate detection in one, and/or a false positive result in the
other; both cases involved HSV-2 detection. The first,
treated as a chronic candidasis infection, was positive by
both nPCR and culture (and also by immunofluores-
cence, though not part of this study). The second, treated
clinically as a non-herpetic aphthous ulcer, was positive
by nPCR alone. The 3 positive assays in the first case
would indicate the infection was genuine, possibly ob-
scured clinically by the presenting candidiasis . However
it could also represent asymptomatic shedding of virus Discussion
h
i The potential for amplicon contamination associated
with NAT assay use is well recognised and makes manda-
tory the use of (a) separate, designated work stations and
(b) a uni-directional work-flow from specimen prepara-
tion to amplified product analysis; this model of opera-
tion is standard in our laboratory . The increased
sensitivity and additional amplification step of nested
NAT assays is thought especially to be coupled with com-
promised specificity resulting from false positive results. Because of this they are commonly regarded as unsuita-
ble for use in routine practice. This study was designed to
address this belief. Its design relied on the predictive val-
ue of clinical judgement for diagnosing mucosal herpetic
infection as the basis for estimating test specificity. In
particular the setting of the study in a department of gen-
itourinary medicine further strengthened the acumen of
clinical diagnosis. False positive results, detection of
asymptomatic shedding and clinical under-estimation of
herpetic infection would be reflected by compromised
assay specificity. The results confirmed high assay spe-
cificities with no significant difference between the nest-
ed NAT format and the current gold standard of virus
culture (Χ2 p = 0.3). This provided convincing evidence
of both (a) the appropriateness of the nested NAT assay's
detection threshold for mucosal herpes infection and (b)
its usefulness in a routine setting. Multiplex HSV-1 and HSV-2 nPCR 64 (22%) (Χ2 p = 0.48)). The cell content improved the
identification of virus by nPCR in those patients with
clinical herpetic infection (1/4 with poor cell content ver-
sus 17/22 with good cell content (Χ2 p = 0.07)) while this
was not so for results obtained by viral culture (1/4 with
poor cell content versus 11/22 with good cell content (Χ2
p = 0.59). The virus type by nPCR concurred with that
isolated in all cases. There were 2 and 1 cases diagnosed
by nPCR and culture respectively where the clinical diag-
nosis was not regarded as suggestive of HSV infection. HSV-2 was detected: (a) by nPCR and culture in a patient
diagnosed with chronic candidiasis and (b) by nPCR
alone in a second patient, diagnosed with an aphthous
ulcer. p
This was undertaken as previously described [13] using
primers recognising the HSV-1 gpD gene and the HSV-2
gpG gene in a multiplex nPCR; HSV-1 and HSV-2 outer
products were 221 and 184 base pairs (bp) while the in-
ner products were 138 and 101 bp respectively. The assay
has respective sensitivities of 0.01 and 0.1 TCID50 for
HSV-1 and HSV-2. Briefly, hot-start was commenced in
a Perkin Elmer GeneAmp 2400 thermal cycler with the
cycling conditions as shown in Table 1. Specimens (10 µl)
were added to 40 µl of mix and subjected to 35 first
round cycles. One microlitre of product was transferred
to 49 µl of second round mix for 25 second round cycles. A positive HSV control and a distilled water negative
control were included in each run. First and second
round products were visualised together on ethidium
bromide-stained 2% agarose gels and photographed (Po-
laroid). Appropriately sized bands present on second
round only, or present on both first and second rounds,
were recorded as positive and strong positive respective-
ly. All positive specimens were re-tested. Statistical analysis The clinical categorisation data for the patients was cor-
related with the results obtained by viral culture and
nPCR. Difference in sensitivity and specificity between
culture and nPCR and also the analysis of the impact of
cell content on virus recovery in patients with clinical
genital herpes infection versus those without evidence of
HSV infection was determined by a two-tailed Chi-
square (Χ2) test. Differences between herpes virus recov-
ery by culture and nPCR in relation to the specimen cell
content was compared using the Fisher exact test. Methods
Patients Table 1: PCR Cycling Conditions
Cycle Conditions
First Round1
Second Round1
Denaturation
94°C – 10 s
94°C – 10 s
Annealing
58°C – 10 s
67°C – 10 s
Extension
72°C – 30 s
72°C – 30 s
Number of Cycles
35
25 Table 1: PCR Cycling Conditions Over a 3 month period 90 patients who presented to the
Department of Genitourinary Medicine, Royal Victoria
Hospital, Belfast, were investigated for evidence of HSV
infection. In addition to their routine assessment they
were also selected for additional clinical categorisation
by the attending consultants into those patients thought
to (a) have, and (b) not have, clinical evidence in keeping
with herpetic infection. Following a detailed history and
examination patients with suspected herpetic infection
were recorded as having : (i) primary HSV; (ii) first clin-
ical episode of non-primary HSV; (iii) recurrent HSV. Those thought not to have herpetic infection involved pa-
tients with ulcerative or inflammatory lesions catego-
rised on clinical examination as non-specific in nature. 1The thermal cycler was held at 94°C for 3 min before cycling began
to facilitate the transfer of specimens, held on ice, for a hot start pro-
cedure. http://www.biomedcentral.com/1471-2334/1/11 BMC Infectious Diseases 2001, 1:11 Virus culture and nPCR Taking the clinical diagnosis as the indicator of HSV in-
fection, nPCR and culture had respective sensitivities of
19/26 (73%) and 12/26 (46%) (Χ2 p = 0.02) and specifi-
cities of 62/64 (97%) and 63/64 (98%) (Χ2 p = 1.0); all
PCR positive specimens were repeatedly reactive. There
was a similar percentage of specimens with sub-optimal
cell content from patients with herpes infection diag-
nosed on clinical grounds compared to those without ob-
vious evidence of HSV infection (4/26 (15%) versus 14/ http://www.biomedcentral.com/1471-2334/1/11 BMC Infectious Diseases 2001, 1:11 http://www.biomedcentral.com/1471-2334/1/11 However our results would suggest the need for validat-
ing specimen quality. For specimens sent in lysis buffer
this is likely to require the quantitative ability associated
with Real-time assays while for those in viral transport
medium assessing cell content would suffice. While
Real-time assays are becoming available they are expen-
sive and are currently outside the cost range of many
routine virology laboratories. In the meantime retention
of culture for HSV diagnosis, or its replacement with
standard PCR, will result in missed laboratory diagnosis
and a compensatory over-reliance on uncorroborated
clinical judgement. or atypical clinical presentation. In the second case the
nPCR assay recorded a strong positive HSV-2 signal
from the submitted specimen. Because the specimen was
not extracted but reactive after direct addition into the
first round reaction mix, we believe the likelihood of con-
tamination at this step to be minimal. Also the detection
was repeatable. In routine practice when clinical details
and laboratory findings conflict we test a further speci-
men; a standard turn-around time of ≤ 24 hours for all
NAT assays in our laboratory allows this approach. or atypical clinical presentation. In the second case the
nPCR assay recorded a strong positive HSV-2 signal
from the submitted specimen. Because the specimen was
not extracted but reactive after direct addition into the
first round reaction mix, we believe the likelihood of con-
tamination at this step to be minimal. Also the detection
was repeatable. In routine practice when clinical details
and laboratory findings conflict we test a further speci-
men; a standard turn-around time of ≤ 24 hours for all
NAT assays in our laboratory allows this approach. While confirming the expected improvement in sensitiv-
ity ((19/26 (73%) and 12/26 (46%) (Χ2 p = 0.02)) of
nPCR, the overall poor performance of both the nPCR
and virus culture assays was unexpected. Virus culture and nPCR Since both have
performed optimally in external quality assessment pro-
grams (NEQAS, run by the Public Health Laboratory
Service for viral culture and the QCCA program run by
the European Society for Clinical Virology for HSV PCR)
we do not believe assay under-performance to be respon-
sible. Additionally we have never encountered a speci-
men that yielded a virus on culture that was PCR
negative, even without specimen extraction, indicating
that PCR inhibitors are not involved or are very uncom-
mon. A number of factors may have accounted for the
observation. We believe the major impact was associated
with specimens containing a sub-optimal cell content
(20%). Our results indicated this had a bearing on the
level of virus detected, especially by culture. Also it could
be suggested that not pre-extracting the specimens may
have compromised the nPCR assay. However from inter-
nal audit findings (unpublished) we have shown that
pre-extraction does not increase the yield of HSV recov-
ery from genital specimens with this assay. Finally, mis-
diagnosed herpetic infections may also have factored
into the low yield. Against a recent report of syphilis in-
creases [18] the potential for its misdiagnosis as atypical
herpetic infection [19] is very real, underlying the impor-
tance of using tests of high sensitivity, which clearly do
not include culture. More fundamentally these results bring into question the
need for the laboratory confirmation of genital herpetic
infection. Currently the laboratory confirmation and typ-
ing of herpetic involvement in genital herpes is recom-
mended practice [20]. Our results indicate that
laboratory results are adding little to clinical judgement
in the majority of cases. They are at best typing the virus
in approximately 70% of the cases investigated. While it
is suggested that the virus type affects patient manage-
ment through tailored counselling, it is questionable
whether in the majority of cases the advice given will al-
ter. By having a blanket approach to the use of laboratory
methods for confirming herpetic infection, which consti-
tutes a major component of most virus laboratories
workload, scarce resources are being diverted from areas
where they could be more useful, e.g. wider access to mu-
tational analysis. We believe it is time to have a more dis-
criminatory approach to the laboratory diagnosis of
genital herpetic infection, restricting it to those cases
where it actually affects patient management, and doing
it well. References 1. Beyrer C, Jitwatcharanan K, Natpratan C, Kaewvichit R, Nelson KE,
Chen CY, et al: Molecular methods for the diagnosis of genital
ulcer disease in a sexually transmitted disease clinic popula-
tion in northern Thailand: predominance of herpes simplex
virus infection. J Infect Dis 1998, 178:243-246 J
2. do Nascimento MC, Sumita LM, de Souza VA, Pannuti CS: Detection
and direct typing of herpes simplex virus in perianal ulcers of
patients with AIDS by PCR. J Clin Microbiol 1998, 36:848-849 p
y
J
3. Mertz KJ, Trees D, Levine WC, Lewis JS, Litchfield B, Pettus KS, et al:
Etiology of genital ulcers and prevalence of human immuno-
deficiency virus coinfection in 10 US cities. The Genital Ulcer
Disease Surveillance Group. J Infect Dis 1998, 178:1795-1798 p J
4. Risbud A, Chan-Tack K, Gadkari D, Gangakhedkar RR, Shepherd ME,
Bollinger R, et al: The etiology of genital ulcer disease by mul-
tiplex polymerase chain reaction and relationship to HIV in-
fection among patients attending sexually transmitted
disease clinics in Pune, India. Sex Transm Dis 1999, 26:55-62 ,
5. Christie SN, McCaughey C, McBride M, Coyle PV: Herpes simplex
type 1 and genital herpes in Northern Ireland. Int J STD AIDS
1997, 8:68-69 6. Benedetti J, Corey L, Ashley R: Recurrence rates in genital her-
pes after symptomatic first-episode infection. Ann Intern Med
1994, 121:847-854 7. Drake S, Taylor S, Brown D, Pillay D: Improving the care of pa-
tients with genital herpes. BMJ 2000, 321:619-623 7. Drake S, Taylor S, Brown D, Pillay D: Improving the care of pa-
tients with genital herpes. BMJ 2000, 321:619-623
8. Beards G, Graham C, Pillay D: Investigation of vesicular rashes
for HSV and VZV by PCR. J Med Virol 1998, 54:155-157 g
p
J
8. Beards G, Graham C, Pillay D: Investigation of vesicular rashes
for HSV and VZV by PCR. J Med Virol 1998, 54:155-157 y
g
for HSV and VZV by PCR. J Med Virol 1998, 54:155-1 9. Slomka MJ, Emery L, Munday PE, Moulsdale M, Brown DW: compar-
ison of PCR with virus isolation and direct antigen detection
for diagnosis and typing of genital herpes. J Med Virol 1998,
55:177-183 10. Espy MJ, Uhl JR, Mitchell PS, Thorvilson JN, Svien KA, Wold AD, et al:
Diagnosis of herpes simplex virus infections in the clinical
laboratory by LightCycler PCR. J Clin Microbiol 2000, 38:795-799 y
y
g
y
J
11. Conclusions A nested amplification format for the laboratory diagno-
sis of mucosal herpetic infection was found to be neces-
sary for adequate test sensitivity while not sacrificing test
specificity. The unexpected poor sensitivity of both as-
says with comparison to clinical evaluation was probably
related to the number of specimens with sub-optimal cell
content (20%), but over-diagnosis of herpetic infection
could have contributed to the findings. The results clear-
ly suggest the need for validating specimen quality, ei-
ther through cell count for specimens in viral transport
medium or Real-time target quantification for those in
lysis buffer. The results question the value of routine lab-
oratory confirmation of mucosal herpetic infection. They
suggest the need for a more discriminatory approach,
taking account of the cell content, and restricting it to
those cases where it actually affects patient manage-
ment. The results of this study indicated that a nested format of
NAT assay was not only suitable for routine application
but essential for achieving adequate sensitivity levels. The sensitivity levels of nested NAT formats therefore
warrant their consideration by laboratories offering di-
agnostic facilities for herpetic infection. The other major
advantage of this multiplex nested format is that it re-
moves the necessity for pre-test extraction and automat-
ically types the virus identified. Nesting with these
primers has proven sufficient to overcome any inhibitors
which would be expected in specimens of this nature and
to date we have been unable through audit to provide ev-
idence to support the need for specimen extraction,
which for our other routine NAT assays is essential. http://www.biomedcentral.com/1471-2334/1/11 BMC Infectious Diseases 2001, 1:11 References Kessler HH, Muhlbauer G, Rinner B, Stelzl E, Berger A, Dorr HW, et
al: Detection of Herpes simplex virus DNA by real-time PCR. J Clin Microbiol 2000, 38:2638-2642 J
12. Schalasta G, Arents A, Schmid M, Braun RW, Enders G: Fast and
type-specific analysis of herpes simplex virus types 1 and 2 by
rapid PCR and fluorescence melting-curve-analysis. Infection
2000, 28:85-91 13. Coyle PV, Desai A, Wyatt D, McCaughey C, O'Neill HJ: comparison
of virus isolation, indirect immunofluorescence and nested
multiplex polymerase chain reaction for the diagnosis of pri-
mary and recurrent herpes simplex type 1 and type 2 infec-
tions. J Virol Methods 1999, 83:75-82 J
14. McDermott SS, McDermott PF, Skare J, Glantz M, Smith TW, Litofsky
NS, et al: Positive CSF HSV PCR in patients with GBM: a note
of caution. Neurology 2000, 54:746-749 gy
15. Hirsch HH, Bossart W: Two-centre study comparing DNA
preparation and PCR amplification protocols for herpes sim-
plex virus detection in cerebrospinal fluids of patients with
suspected herpes simplex encephalitis. J Med Virol 1999, 57:31-
35 Publish with BioMed Central and every
scientist can read your work free of charge
"BioMedcentral will be the most significant development for
disseminating the results of biomedical research in our lifetime."
Paul Nurse, Director-General, Imperial Cancer Research Fund
Publish with BMC and your research papers will be:
available free of charge to the entire biomedical community
peer reviewed and published immediately upon acceptance
cited in PubMed and archived on PubMed Central
yours - you keep the copyright
editorial@biomedcentral.com
Submit your manuscript here:
http://www.biomedcentral.com/manuscript/
BioMedcentral.com Publish with BioMed Central and every
scientist can read your work free of charge 16. Dumas AL, de Ancos E, Herbort CP: [Evaluation of the method
of DNA amplification (PCR, polymerase chain reaction) for
diagnosis of superficial ocular herpes], Klin Monatsbl Augenheilkd
1992, 200:472-475 17. O'Neill HJ, Russell JD, Wyatt DE, McCaughey C, Coyle PV: Isolation
of viruses from clinical specimens in microtitre plates with
cells inoculated in suspension. J Virol Methods 1996, 62:169-178 17. O'Neill HJ, Russell JD, Wyatt DE, McCaughey C, Coyle PV: Isolation
of viruses from clinical specimens in microtitre plates with
cells inoculated in suspension. J Virol Methods 1996, 62:169-178
18. Higgins SP, Sukthankar A, Mahto M, Jarvis RR, Lacey HB: Syphilis in-
creases in Manchester, UK. Lancet 2000, 355:1466 p
J
,
18. References Higgins SP, Sukthankar A, Mahto M, Jarvis RR, Lacey HB: Syphilis in-
creases in Manchester, UK. Lancet 2000, 355:1466 ,
19. Graham D, Higgins SP: Patients with primary herpes should be
screened for syphilis. BMJ 2001, 322:434 yp
J
20. National guideline for the management of genital herpes: Clinical Ef-
fectiveness Group (Association of Genitourinary Medicine
and the Medical Society for the Study of Venereal Diseases). Sex Transm Infect 1999, 75 Suppl 1:S24-S28
|
https://openalex.org/W4304809212
|
https://www.mdpi.com/2227-7390/10/20/3756/pdf?version=1666693061
|
Latin
| null |
Stochastic Analysis of a Hantavirus Infection Model
|
Mathematics
| 2,022
|
cc-by
| 10,117
|
Yousef Alnafisah 1,* and Moustafa El-Shahed 2 Yousef Alnafisah 1,* and Moustafa El-Shahed 2 1
Department of Mathematics, College of Sciences, Qassim University, 1
Department of Mathematics, College of Sciences, Qassim University,
P.O. Box 6644, Buraydah 51452, Saudi Arabia 1
Department of Mathematics, College of Sciences, Qassim University,
P.O. Box 6644, Buraydah 51452, Saudi Arabia
2
Department of Mathematics, Unaizah College of Sciences and Arts, Qassim University,
P.O. Box 3771, Unaizah 51911, Saudi Arabia
*
Correspondence: nfiesh@qu edu sa 1
Department of Mathematics, College of Sciences, Qassim University,
P.O. Box 6644, Buraydah 51452, Saudi Arabia
2
Department of Mathematics, Unaizah College of Sciences and Arts, Qassim University,
P.O. Box 3771, Unaizah 51911, Saudi Arabia
*
Correspondence: nfiesh@qu.edu.sa 1
Department of Mathematics, College of Sciences, Qassim University,
P.O. Box 6644, Buraydah 51452, Saudi Arabia
2
Department of Mathematics, Unaizah College of Sciences and Arts, Qassim University,
P.O. Box 3771, Unaizah 51911, Saudi Arabia
*
C
d
fi
h@
d ,
y
,
2
Department of Mathematics, Unaizah College of Sciences and Arts, Qassim University,
P.O. Box 3771, Unaizah 51911, Saudi Arabia *
Correspondence: nfiesh@qu.edu.sa Abstract: In this paper, a stochastic Hantavirus infection model is constructed. The existence,
uniqueness, and boundedness of the positive solution of the stochastic Hantavirus infection model
are derived. The conditions for the extinction of the Hantavirus infection from the stochastic system
are obtained. Furthermore, the criteria for the presence of a unique ergodic stationary distribution
for the Hantavirus infection model are established using a suitable Lyapunov function. Finally,
the importance of environmental noise in the Hantavirus infection model is illustrated using the
Milstein method. Keywords: Hantavirus; Milstein method; stochastic; ergodic stationary distribution; biodiversity MSC: 34D20; 37N25; 92D25; 37A50 mathematics Hantaviruses may be transmitted to humans through the saliva of rodents, such as
mice and rats, their urine or feces, or through contact and inhalation of air contaminated
with droplets of rodent saliva or dust contaminated with their dry droppings. This may
result in fatal diseases in humans, such as pulmonary infection syndrome and hemorrhagic
fever. Hantavirus pulmonary infection syndrome is rare, but fatal [1]. The Southwest USA
experienced a Hantavirus outbreak in 1993, which led to a high mortality rate. Mathemat-
ical modeling of the spread of the Hantavirus infection is one of the important tools for
understanding and interpreting different interactions between susceptible and infected
mice. A simple mathematical model was developed by Abramson [1] to simulate the
propagation of the virus, and it was shown to be capable of simulating some features of
infection. In real life, rodents and so-called ‘alien’ species share the resources available
in the environment. Therefore, rodents do not only share resources among themselves. Biodiversity and the competition between “alien” species and rodents should be taken
into account. According to Peixoto [2] and Solomon [3], biodiversity plays an important
role in controlling the spread of Hantavirus. The rodents and nonhost species can exert
pressure on one another through the level of their respective interspecific competition. In order to account for the biodiversity effect, Peixoto [2] extended the basic Abramson
model by including a nonhost alien species. Yusof et al. [4] extended the Peixoto model
to include the effects of harvesting. Some studies of the modeling of Hantavirus infection
include [5–17]. According to [18,19], the intrinsic growth rate, mortality rate, carrying
capacity, competition coefficients, and other system parameters would be impacted by
environmental changes. Following [20], one can estimate the birth and death rates by an
average value plus errors. In general, by the well-known central limit theorem, the error
term follows a normal distribution; thus, for a short correlation time, one can assume that
the birth and death rates are subjected to the Gaussian white noise. The stochastic effect,
which can be significant because the environmental conditions for its transmission are Citation: Alnafisah, Y.; El-Shahed, M. Stochastic Analysis of a Hantavirus
Infection Model. Mathematics 2022,
10, 3756. Article
Stochastic Analysis of a Hantavirus Infection Model Article 2. Hantavirus Model In this section, we first present Abramson’s model that investigates the spread of Han-
tavirus infection. In this model, the total population of rodents is divided into susceptible
mice x1(t) and infected mice x2(t). The Abramson model’s equations are as follows [1]: dx1
dt = b(x1 + x2) −cx1 −x1
k (x1 + x2) −ax1x2,
dx2
dt = ax1x2 −x2
k (x1 + x2) −cx2,
(1) (1) where b is the birth rate, c is the death rate, k is related to the carrying capacity of the
environment, and a is the constant infection rate. The Peixoto model of competition
Hantavirus dynamics including the nonhost alien species x3(t) takes the form [2]: dx1
dt = b(x1 + x2) −cx1 −x1
k (x1 + x2 + ρx3) −ax1x2,
dx2
dt = ax1x2 −x2
k (x1 + x2 + ρx3) −cx2,
dx3
dt = (β −γ)x3 −x3
k (x3 + δ(x1 + x2)),
(2) (2) where β and γ are the alien population’s birth and death rates, respectively. ρ is the inter-
specific competition strength exerted by the alien population onto the mouse population,
and δ is the interspecific competition strength exerted by the mouse population onto the
alien population. In the present paper, the Hantavirus infection model (2) will extend to
include the stochastic effects as follows: dx1 =
h
b(x1 + x2) −cx1 −x1
k (x1 + x2 + ρx3) −ax1x2
i
dt + σ1x1 dB1,
dx2 =
h
ax1x2 −x2
k (x1 + x2 + ρx3) −cx2
i
dt + σ2x2 dB2,
dx3 =
h
(β −γ)x3 −x3
k (x3 + δ(x1 + x2))
i
dt + σ3x3 dB3,
(3) (3) where B = {B1, B2, B3, t ≥0} represents the three-dimensional standard Brownian motions. The stochastic extension of the deterministic Abramson model (1) is recovered by setting
ρ = 0 and ignoring the third equation of system (3). ρ = 0 and ignoring the third equation of system (3). https://doi.org/10.3390/
math10203756 Academic Editors: Calogero Vetro
and Omar Bazighifan Academic Editors: Calogero Vetro
and Omar Bazighifan Received: 7 August 2022
Accepted: 8 October 2022
Published: 12 October 2022 Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
iations. Copyright:
© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article
distributed
under
the
terms
and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/). https://www.mdpi.com/journal/mathematics Mathematics 2022, 10, 3756. https://doi.org/10.3390/math10203756 Mathematics 2022, 10, 3756 2 of 15 2 of 15 subject to ecological randomness, is not taken into account by the deterministic Peixoto
Hantavirus infection model. The primary purpose of this paper is to formulate a stochastic
dynamic model to predict Hantavirus infection and identify the key factors that signifi-
cantly affect the disease spread and control of Hantavirus infection. Hence, our goal in this
paper is to provide a comprehensive analysis of the stochastic Hantavirus infection model,
especially the existence and uniqueness of a positive global solution and the conditions for
the extinction of the Hantavirus infection. This approach has recently been used in many
papers for the analysis of stochastic predator–prey systems [21–25], stochastic epidemic
models [26–33], and stochastic analysis methods [34–36]. This paper is arranged as follows:
In Section 3, the existence and uniqueness of a positive global solution of the stochastic
Hantavirus infection model are investigated, and sufficient conditions for the extinction of
the infection from the stochastic system are obtained. In Section 4, some numerical simu-
lations are presented to verify the obtained theoretical results. Finally, Section 5 contains
the conclusion. 3. Dynamics of the Stochastic Model Firstly, we shall demonstrate the existence and uniqueness of a positive global solution
of the Hantavirus infection model (3) in the following theorem. Mathematics 2022, 10, 3756 3 of 15 3 of 15 Theorem 1. There exists a unique solution of the Hantavirus infection model (3) for positive initial
values, and the positive global solution remains in R3+ with probability one. Proof. Assume (x1(t), x2(t), x3(t)) is the solution to the Hantavirus infection model (3) for
t ∈[0, τe), where τe is the explosion time. Using the following variables X1(t) = ln x1(t), X2(t) = ln x2(t), X3(t) = ln x3(t), one obtains one obtains d X1(t) =
"
b(1 + eX2
eX1 ) −c −1
k
h
eX1 + eX2 + ρeX3
i
−aeX2 −σ2
1
2
#
dt + σ1 dB1,
d X2(t) =
"
aeX1 −1
k
h
eX1 + eX2 + ρeX3
i
−c −σ2
2
2
#
dt + σ2 dB2,
d X3(t) =
"
(β −γ) −1
k
h
eX3 + δ(eX1 + eX2
i
−σ2
3
2
#
dt + σ3 dB3. (4) (4) The transformed system (4) has a a unique local solution on [0, τe), as the coefficients
satisfy the local Lipschitz conditions. Next, we prove that τe = ∞almost surely. Let s0 > 0
be sufficiently large for every coordinate in the interval [ 1
s0 , s0]. For each integer s > s0, we
can define τs = inf
t ∈[0, τe) : min{x1(t), x2(t), x3(t)} ̸∈(1
s , s) or max{x1(t), x2(t), x3(t)} ̸∈(1
s , s)
. (5)
Using the following positive definite C2 function V1(x1, x2, x3) as
V1(x1, x2, x3) = (x1 + 1 −lnx1) + (x2 + 1 −lnx2) + (x3 + 1 −lnx3),
(6) τe) : min{x1(t), x2(t), x3(t)} ̸∈(1
s , s) or max{x1(t), x2(t), x3(t)} ̸∈(1
s , s)
. 3. Dynamics of the Stochastic Model (5)
Using the following positive definite C2 function V1(x1, x2, x3) as (5) V1(x1, x2, x3) = (x1 + 1 −lnx1) + (x2 + 1 −lnx2) + (x3 + 1 −lnx3),
(6) (6) one obtains dV1 =
(x1 −1)
b + bx2
x1
−c −1
k [x1 + x2 + ρx3] −ax2
+ (x2 −1)
ax1 −1
k [x1 + x2 + ρx3] −c
+(x3 −1)
β −γ −1
k (x3 + δ(x1 + x2))
+ 1
2
3
∑
i=1
σ2
i
dt + σ1(x1 −1)dB1 + σ2(x2 −1)dB2 + σ3(x3 −1)dB3
≤
(b + 2 + δ
k
)x1 + (b + a + 2 + δ
k
)x2 + (β −γ + 2ρ + 1
k
)x3 + 2c + 1
2
3
∑
i=1
σ2
i
dt + σ1(x1 −1)dB1
+σ2(x2 −1)dB2 + σ3(x3 −1)dB3. +σ2(x2 −1)dB2 + σ3(x3 −1)dB3. Using the inequality A ≤2(A + 1 −lnA), for any A > 0, one obtains dV1 ≤
2(b + 2 + δ
k
)(x1 + 1 −lnx1) + 2(b + a + 2 + δ
k
)(x2 + 1 −lnx2) + 2(β −γ + 2ρ + 1
k
)(x3 + 1 −lnx3)
+
2c + 1
2
3
∑
i=1
σ2
i
!
dt + σ1(x1 −1)dB1 + σ2(x2 −1)dB2 + σ3(x3 −1)dB3, which means that dV1 ≤K(1 + V1)dt + σ1(x1 −1)dB1 + σ2(x2 −1)dB2 + σ3(x3 −1)dB3,
(7) (7) where K = max
(
2(b + 2 + δ
k
), 2(b + a + 2 + δ
k
), 2(β −γ + 2ρ + 1
k
), 2c + 1
2
3
∑
i=1
σ2
i
)
. (8) (8) Mathematics 2022, 10, 3756 4 of 15 4 of 15 Integrating form 0 to t1 ∧τs and taking the expectation, one obtains EV1(x1(t1 ∧τs), x2(t1 ∧τs), x3(t1 ∧τs)) ≤V1(x1(0), x2(0), x3(0)) + KT + K
Z t1∧τs
0
EV1 dt. Following [18,37], using Grownwall’s inequality, one obtains
EV1(x1(t1 ∧τs), x2(t1 ∧τs), x3(t1 ∧τs)) ≤[V1(x1(0), x2(0), x3(0)) + KT]eKT = K2. EV1(x1(t1 ∧τs), x2(t1 ∧τs), x3(t1 ∧τs)) ≤V1(x1(0), x2(0), x3(0)) + KT + K
Z t1∧τs
0
EV1 dt. 3. Dynamics of the Stochastic Model F ll
i
[18 37]
i
G
ll’ i
lit
bt i Following [18,37], using Grownwall’s inequality, one obtains Following [18,37], using Grownwall’s inequality, one obtains Following [18,37], using Grownwall’s inequality, one obtains EV1(x1(t1 ∧τs), x2(t1 ∧τs), x3(t1 ∧τs)) ≤[V1(x1(0), x2(0), x3(0)) + KT]eKT = K2. EV1(x1(t1 ∧τs), x2(t1 ∧τs), x3(t1 ∧τs)) ≤[V1(x1(0), x2(0), x3(0)) + KT]eKT = K2. The remaining part of the proof is similar to [37,38]; therefore, it can be omitted. Theorem 1 shows that the stochastic Hantavirus infection model (3) has a positive
global solution remaining in R3+ with probability one. Next, we establish the boundedness
property of the Hantavirus infection model (3). Theorem 2. Let H(t) = x1(t) + x2(t) + x3(t); then, the following inequality holds: lim
t→∞sup E[H(t)] ≤β2
1k
2β2
almost surely, where β1 = max{b, β}, and β2 = min{c, γ}. lim
t→∞sup E[H(t)] ≤β2
1k
2β2 t→∞
2β2
almost surely, where β1 = max{b, β}, and β2 = min{c, γ}. almost surely, where β1 = max{b, β}, and β2 = min{c, γ}. almost surely, where β1 = max{b, β}, and β2 = min{c, γ}. Proof. According to the stochastic Hantavirus infection model, (3) For (x1(t), x2(t), x3(t)) ∈R3+, we define the following function V2(x(t), y(t), z(t)) = x(t)2 + y(t)2 + z(t)2. (9) (9) By the Itô formula, one has dV2 = LV2dt + 2σ1x2
1dB1 + 2σ2x2
2dB2 + 2σ3x2
3dB3,
(10) (10) where LV2(x1, x2, x3) =2
"
bx2
1 + bx1x2 −cx2
1 −x2
1
2 (x1 + x2 + ρx3) −ax2
1x2 + ax1x2
2 −cx2
2 −x2
2
2 (x1 + x2 + ρx3)
#
+ 2x2
3
(β −γ) −1
k (x3 + δ(x1 + x2))
+ σ2
1 x2
1 + σ2
2 x2
2 + σ2
3 x2
3
≤(σ2
1 + 2b −2c + 1)x2
1 +
σ2
2 −2c + 1
x2
2 +
σ2
3 + 2(β −γ) + 1
x2
3 + 2ax1x2
2 −(x2
1 + x2
2 + x Assume f1(x1, x2, x3) = (σ2
1 + 2b −2c + 1)x2
1 +
σ2
2 −2c + 1
x2
2 +
σ2
3 + 2(β −γ) + 1
x2
3
+2ax1x2
2. According to Theorem 2, one can find that the function f1(x1, x2, x3) has an upper
bound. Let M = sup f1(x1, x2, x3) + 1. As a result, Assume f1(x1, x2, x3) = (σ2
1 + 2b −2c + 1)x2
1 +
σ2
2 −2c + 1
x2
2 +
σ2
3 + 2(β −γ) + 1
x2
3
+2ax1x2
2. According to Theorem 2, one can find that the function f1(x1, x2, x3) has an upper
bound. Let M = sup f1(x1, x2, x3) + 1. As a result, dV2 = (M −V2)dt + 2σ1x2
1dB1 + 2σ2x2
2dB2 + 2σ3x2
3dB3. (11) (11) By the Itô formula, one obtains By the Itô formula, one obtains d(etV2) ≤etN1dt + eth
2σ1x2
1dB1 + 2σ2x2
2dB2 + 2σ3x2
3dB3
i
. Consequently, etV2(x1(t), x2(t), x3(t)) ≤V2(x1(0), x2(0), x3(0)) + Met −M; etV2(x1(t), x2(t), x3(t)) ≤V2(x1(0), x2(0), x3(0)) + Met −M; hence, hence, lim
t→∞sup E[|X(t)|2] ≤M. lim
t→∞sup E[|X(t)|2] ≤M. According to Chebyshev’s inequality, one obtains According to Chebyshev’s inequality, one obtains P[|X(t)| ≥η] ≤E[|X(t)|2]
η2
, where η =
√
M
√ν , ν > 0. Then, where η =
√
M
√ν , ν > 0. Then, lim
t→∞sup P[|X(t)| ≥η] ≤M
η2 = ν. This completes the proof. Proof. According to the stochastic Hantavirus infection model, (3) Proof. According to the stochastic Hantavirus infection model, (3) Proof. According to the stochastic Hantavirus infection model, (3) dH(t) ≤
b(x1 + x2) −c(x1 + x2) −1
k (x1 + x2)2 −ρx3
k (x1 + x2) + (β −γ)x3 −x3
k (x3 + δ(x1 + x2))
dt
+σ1x1 dB1 + σ2x2 dB2 + σ3x3 dB3
≤−1
k
(x1 + x2)2 −bk(x1 + x2) + b2k2
4
+ b2k
4 −1
k
x2
3 −βkx3 + β2k2
4
+ β2k
4 −c(x1 + x2) −γx3
+σ1x1 dB1 + σ2x2 dB2 + σ3x3 dB3 ≤−1
k
(x1 + x2)2 −bk(x1 + x2) + b2k2
4
+ b2k
4 −1
k
x2
3 −βkx3 + β2k2
4
+ β2k
4 −c(x1 + x2) −γx
+σ1x1 dB1 + σ2x2 dB2 + σ3x3 dB3 ≤β2
1k
2
−β2(x1 + x2 + x3) + σ1x1 dB1 + σ2x2 dB2 + σ3x3 dB3. ≤β2
1k
2
−β2(x1 + x2 + x3) + σ1x1 dB1 + σ2x2 dB2 + σ3x3 dB3. ≤β2
1k
2
−β2(x1 + x2 + x3) + σ1x1 dB1 + σ2x2 dB2 + σ3x3 dB3. Consequently, Consequently, H(t) ≤H(0) + β2
1k
2 t −β2
Z t
0 H(s)ds +
Z t
0 [σ1x1dB1 + σ2x2dB2 + σ3x3dB3]ds. Using the strong law of large numbers, one obtains Using the strong law of large numbers, one obtains E[H(t)] ≤H(0) + β2
1k
2 t −β2
Z t
0 E(H(s))ds. Consequently,
dE[H(t)]
dt
+ β2E[H(t)] ≤β2
1k
2 . Thus, one obtains
lim
t→∞sup E[H(t)] ≤β2
1k
2β2
. Consequently, dE[H(t)]
dt
+ β2E[H(t)] ≤β2
1k
2 . lim
t→∞sup E[H(t)] ≤β2
1k
2β2
. Thus, one obtains According to Theorem 2, the solution of the Hantavirus infection model (3) is uniformly
bounded in mean, and as a result, the deterministic Hantavirus infection model (2) is
uniformly bounded. Mathematics 2022, 10, 3756 5 of 15 5 of 15 Theorem 3. If σ2
1 + 2b + 1 < 2c, σ2
2 + 1 < 2c, σ2
3 + 2β + 1 < 2γ, then the solutions of (3) are
stochastically ultimate bounded. Theorem 3. If σ2
1 + 2b + 1 < 2c, σ2
2 + 1 < 2c, σ2
3 + 2β + 1 < 2γ, then the solutions of (3) are
stochastically ultimate bounded. Proof. Proof. According to the stochastic Hantavirus infection model, (3) Next, we establish the conditions for the extinction of the Hantavirus infection
model (3). Theorem 4. For any positive initial conditions, if b < c and β < σ2
3
2 + γ, then the populations of
the Hantavirus infection model (3) will be extinct with probability one. Mathematics 2022, 10, 3756 6 of 15 6 of 15 Proof. Using the Itô formula, one obtains Proof. Using the Itô formula, one obtains Proof. Using the Itô formula, one obtains Proof. Using the Itô formula, one obtains Proof. Using the Itô formula, one obtains Proof. Using the Itô formula, one obtains d(ln(x1 + x2)) =
b −(x1 + x2)
k
−ρx3
k
−c −
1
2(x1 + x2)2
σ2
1 x2
1 + σ2
2 x2
2
dt
+
σ1x1
(x1 + x2)dB1 +
σ2x2
(x1 + x2)dB2
≤(b −c)dt +
σ1x1
(x1 + x2)dB1 +
σ2x2
(x1 + x2)dB2. As a result, which implies that lim
t→∞supln[x1(t) + x2(t)]
t
≤b −c < 0
almostsurely. Hence, lim
t→∞[x1(t) + x2(t)] = 0. According to the third equation of the Hantavirus infection system (3), one obtains According to the third equation of the Hantavirus infection system (3), one obtains d(lnx3(t)) =
"
(β −γ) −1
k (x3 + δ(x1 + x2)) −σ2
3
2
#
dt + σ3 dB3. (12) (12) Consequently, lnx3(t) = lnx3(0) −1
k
Z t
0 [x3(s) + δ(x1(s) + x2(s))]ds + ((β −γ) −σ2
3
2 ) t + σ3 B3,
(13) (13) and it follows that and it follows that lim
t→∞suplnx3(t)
t
≤(β −γ) −σ2
3
2 < 0
almostsurely. Thus, limt→∞x3(t) = 0. As a result, if b < c, and β < σ2
3
2 + γ, then the populations of
the Hantavirus infection model (3) will be extinct with probability one. The asymptotic stability of the Hantavirus infection system (3) is established in the
following theorem. Theorem 5. For any positive initial conditions, the trivial solution of the Hantavirus infection
model (3) is stochastically asymptotically stable in probability if σ2
1
2 + b < c, σ2
3
2 + β < γ, and
( σ2
1
2 + b −c)( σ2
2
2 −c) > b2
4 . Proof. The first step is to consider the following linearized Hantavirus infection model
about the origin dx1 = [(b −c)x1 + bx2]dt + σ1x1 dB1,
dx2 = −cx2dt + σ2x2 dB2,
dx3 = (β −γ)x3dt + σ3x3 dB3. (14) dx1 = [(b −c)x1 + bx2]dt + σ1x1 dB1,
dx2 = −cx2dt + σ2x2 dB2,
(14) (14) dx2 = −cx2dt + σ2x2 dB2,
(14) dx3 = (β −γ)x3dt + σ3x3 dB3. dx3 = (β −γ)x3dt + σ3x3 dB3. Consider the following Lyapunov function Consider the following Lyapunov function Consider the following Lyapunov function V3 = 1
2
h
x2
1(t) + x2
2(t) + x2
3(t)
i
. Theorem 6. The stochastic Hantavirus infection model (3) has the following property lim
→∞sup1
t E
Z t
0
h
(x1(u) −x0)2 + x2(u)2 + x3(u)2i
du ≤
h
(b + x0
k ) + (β −γ + x0ρ
k )
i β2
1k2
2β2
+
σ2
1
2 −(b −c)
! x0k Proof. In order to prove Theorem 6, one can define the following function V4(x1, x2, x3) =
x1 −x0 + ln( x1
x0
)
+ x2 + x3. (17) (17) Applying the Itô formula leads to dV4 =
(x1 −x0)
b + x2
x1
−c −1
k (x1 + x2 + ρx3) −ax2
+ x0σ2
1
2
+
−cx2 −x2
k (x1 + x2 + ρx3) + ax1x2
+
(β −γ)x3 −x3
k (x3 + δ(x1 + x2))
+ σ1(x1 −x0)dB1 + σ2x2dB2 + σ3x3 dB3
≤
−1
k (x1 −x0)2 −1
k x2
2 −1
k x2
3 + (b + x0
k )x2 + (β −γ + x0q
k )x3 +
x0σ2
1
2
−(b −c)x0
!
dt + σ1(x1 −x0)dB1
+σ2x2dB2 + σ3x3dB3
≤
−1
k (x1 −x0)2 −1
k x2
2 −1
k x2
3 + (b + x0
k )x2 + (β −γ + x0ρ
k )x3 +
x0σ2
1
2
−(b −c)x0
!
dt + σ1(x1 −x0)dB1 ≤
−1
k (x1 −x0)2 −1
k x2
2 −1
k x2
3 + (b + x0
k )x2 + (β −γ + x0ρ
k )x3 +
x0σ2
1
2
−(b −c)x0
!
dt + σ1(x1 −x0)dB1 ! +σ2x2dB2 + σ3x3dB3. +σ2x2dB2 + σ3x3dB3. Proof. Using the Itô formula, one obtains (15) (15) Mathematics 2022, 10, 3756 7 of 15 7 of 15 One can compute One can compute One can compute LV3 =
"
σ2
1
2 + b −c
#
x2
1 +
"
σ2
2
2 −c
#
x2
2 +
"
σ2
3
2 + β −γ
#
x2
3 + bx1x2. (16) (16) One can rewrite LV3 to be LV3 = 1
2XTQX, where X = (x1, x2, x3) and Q =
2( σ2
1
2 + b −c)
b
0
b
2( σ2
2
2 −c)
0
0
0
2( σ2
3
2 + β −γ)
. The matrix Q will be negative definite if σ2
1
2 + b < c, σ2
3
2 + β < γ, and ( σ2
1
2 + b −c)( σ2
2
2 −
c) > b2
4 . As indicated by [39], the linearized stochastic Hantavirus infection model (14)
is stochastically stable in the large if LV3 is a negative-definite function. According to
Arnold [40], the trivial solution of the nonlinear stochastic Hantavirus infection model (3)
is stochastically asymptotically stable if the linear stochastic Hantavirus model (14) is
stochastically asymptotically stable. The equilibrium point E = (x0, 0, 0), where x0 = k(b −c) is the Hantavirus-free equilib-
rium of the deterministic Hantavirus infection model (2), but it may be not an equilibrium
of the stochastic Hantavirus infection model (3). Next, we investigate the asymptotic
property around E for the stochastic system. Theorem 6. The stochastic Hantavirus infection model (3) has the following property Therefore, lim
t→∞sup 1
t E
Z t
0
h
(x1(u) −x0)2 + x2(u)2 + x3(u)2i
du ≤
h
(b + x0
k ) + (β −γ + x0ρ
k )
i β2
1k2
2β2
+
σ2
1
2 −(b −c)
! x0k. lim
t→∞sup 1
t E
Z t
0
h
(x1(u) −x0)2 + x2(u)2 + x3(u)2i
du ≤
h
(b + x0
k ) + (β −γ + x0ρ
k )
i β2
1k2
2β2
+ lim
t→∞sup 1
t E
Z t
0
h
(x1(u) −x0)2 + x2(u)2 + x3(u)2i
du ≤
h
(b + x0
k ) + (β −γ + x0ρ
k )
i β2
1k2
2β2
+
σ2
1
2 −(b −c)
! x0k. From Theorem 6, one can see that the Hantavirus infection will tend to die out when
the intensity of the stochastic perturbations σ1 is small enough. In the following theorem, we
establish the criteria for the existence of an ergodic stationary distribution in the stochastic
Hantavirus infection model (3) using the method of Khasminskii [41]. According to [42,43],
one can investigate the stationary distribution for the Hantavirus infection model (3)
instead of asymptotically stable equilibria. Before giving the main theorem, we first state
the following Lemma From Theorem 6, one can see that the Hantavirus infection will tend to die out when
the intensity of the stochastic perturbations σ1 is small enough. In the following theorem, we
establish the criteria for the existence of an ergodic stationary distribution in the stochastic g
y
Hantavirus infection model (3) using the method of Khasminskii [41]. According to [42,43],
one can investigate the stationary distribution for the Hantavirus infection model (3)
instead of asymptotically stable equilibria. Before giving the main theorem, we first state
the following Lemma Lemma 1 ([41]). The Markov process X(t) has a unique ergodic stationary distribution π(.) if there
exists a bounded closed domain U1 ⊂Rd with regular boundary Γ, having the following properties:
H1 : there is a positive number M0 such that ∑d
i,j=1 aij(x)ηiηj ≥M0|η2|, x ∈U1, η ∈Rd,
H2 : there exists a nonnegative C2 function V such that LV is negative on Rd\U1. Lemma 1 ([41]). Consequently, 0 ≤E[V4(x1(t), x2(t), x3(t))] ≤E[V4(x1(0), x2(0), x3(0))]
+E
Z t
0
"
−1
k (x1(u) −x0)2 −1
k x2(u)2 −1
k x3(u)2 + (b + x0
k )x2(u) + (β −γ + x0ρ
k )x3(s) +
x0σ2
1
2
−(b −c)x0
!#
du, 8 of 15 Mathematics 2022, 10, 3756 using Theorem 2 one obtains using Theorem 2, one obtains using Theorem 2, one obtains using Theorem 2, one obtains using Theorem 2, one obtains E
Z t
0
1
k (x1(u) −x0)2 + 1
k x2(u)2 + 1
k x3(u)2
du ≤E(V4(x1(0), x2(0), x3(0))) + (b + x0
k ) β2
1k
2β2
t
+(β −γ + x0ρ
k ) β2
1k
2β2
t +
x0σ2
1
2
−(b −c)x0
! t. Therefore, The Markov process X(t) has a unique ergodic stationary distribution π(.) if there
exists a bounded closed domain U1 ⊂Rd with regular boundary Γ, having the following properties:
H
th
i
iti
b
M
h th t ∑d
( )
≥M | 2|
∈U
∈Rd H1 : there is a positive number M0 such that ∑d
i,j=1 aij(x)ηiηj ≥M0|η2|, x ∈U1, η ∈Rd,
H2 : there exists a nonnegative C2 function V such that LV is negative on Rd\U1. p
i,j
1
j( )η ηj
|η |
η
H2 : there exists a nonnegative C2 function V such that LV is negative on Rd\U1. Remark 1. The positive equilibrium point E = (x∗
1, x∗
2, x∗
3) of the deterministic Peixoto system (2)
satisfies (b −c) = 1
k (x∗
1 + x∗
2 + ρx∗
3) + ax∗
2 −b x∗
2
x∗
1
, c = ax∗
2 −1
k (x∗
1 + x∗
2 + ρx∗
3),
(β −γ) = 1
k (x∗
3 + δ(x∗
1 + x∗
2)), where x∗
1 = b
a, x∗
2 = ak(b −c) −b(1 −ρδ) −akρ(β −γ)
a(1 −ρδ)
,
x∗
3 = k[(β −γ) −δ(b −c)]
1 −ρδ
,
0 < ρ < 1, 0 < δ < 1, (β −γ) > δ(b −c) and β > γ, (β −γ) > δ(b −c), ak(b −c) >
b(1 −ρδ) + akρ(β −γ). Theorem 7. Assume (ak −1)(1 −ρ) > δ, ρ + δ + 2akρ < 1, b > c, β > γ, 0 < ρδ < 1,
(β −γ) > δ(b −c), ak(b −c) > b(1 −ρδ) + akρ(β −γ), and
m < min
((ak −1)(1 −ρ) −δ)(x∗)2 (ak + akρ + 1)(x∗)2 (1 −ρ −δ −2akρ)(x∗)2
x∗
1 = b
a, x∗
2 = ak(b −c) −b(1 −ρδ) −akρ(β −γ)
a(1 −ρδ)
,
x∗
3 = k[(β −γ) −δ(b −c)]
1 −ρδ
, a
a(1
ρδ)
1
ρδ
0 < ρ < 1, 0 < δ < 1, (β −γ) > δ(b −c) and β > γ, (β −γ) > δ(b −c), ak(b −c) >
b(1 −ρδ) + akρ(β −γ). Theorem 7. Therefore, Assume (ak −1)(1 −ρ) > δ, ρ + δ + 2akρ < 1, b > c, β > γ, 0 < ρδ < 1,
(β −γ) > δ(b −c), ak(b −c) > b(1 −ρδ) + akρ(β −γ), and
m < min
((ak −1)(1 −ρ) −δ)
k
(x∗
1)2, (ak + akρ + 1)
k
(x∗
2)2, (1 −ρ −δ −2akρ)
k
(x∗
3)2
, 0 < ρ < 1, 0 < δ < 1, (β −γ) > δ(b −c) and β > γ, (β −γ) > δ(b −c), ak(b −c) >
b(1 −ρδ) + akρ(β −γ). Theorem 7. Assume (ak −1)(1 −ρ) > δ, ρ + δ + 2akρ < 1, b > c, β > γ, 0 < ρδ < 1,
(β −γ) > δ(b −c), ak(b −c) > b(1 −ρδ) + akρ(β −γ), and
m < min
((ak −1)(1 −ρ) −δ)
k
(x∗
1)2, (ak + akρ + 1)
k
(x∗
2)2, (1 −ρ −δ −2akρ)
k
(x∗
3)2
, where m = b( b2k
4c + x∗
1) + (ak−1)x∗
1σ2
1
2
+ (ak−1)x∗
2σ2
2
2
+ x∗
3σ2
3
2 ; then, the stochastic Hantavirus infection
model (3) has an ergodic stationary distribution for any given positive initial values. where m = b( b2k
4c + x∗
1) + (ak−1)x∗
1σ2
1
2
+ (ak−1)x∗
2σ2
2
2
+ x∗
3σ2
3
2 ; then, the stochastic Hantavirus infection
model (3) has an ergodic stationary distribution for any given positive initial values. Proof. In order to prove Theorem 7, one needs only to validate conditions H1 and H2 of
Lemma 1. The first step is to validate condition H1 of Lemma 1. Following [44], one can
define the following nonnegative C2 function ) = α1
x1 −x∗
1 −x∗
1ln x1
x∗
1
+ α2
x2 −x∗
2 −x∗
2ln x2
x∗
2
+ α3
x3 −x∗
3 −x∗
3ln x3
x∗
3
. Therefore, (18) (18) Applying the Itô formula leads to Applying the Itô formula leads to Mathematics 2022, 10, 3756 9 of 15 LV5 = α1(x1 −x∗
1)
b −c + bx2
x1
−1
k (x1 + x2 + ρx3) −ax2
+ α2(x2 −x∗
2)
ax1 −1
k (x1 + x2 + ρx3) −c
+ α3(x3 −x∗
3)
β −γ −1
k (x3 + δ(x1 + x2))
+ α1x∗
1σ2
1
2
+ α2x∗
2σ2
2
2
+ α3x∗
3σ2
3
2
≤−α1
k (x1 −x∗
1)2 −α2
k (x2 −x∗
2)2 −α3
k (x3 −x∗
3)2 −
α1( ak + 1
k
) −α2( ak −1
k
)
(x1 −x∗
1)(x2 −x∗
2)
−
α1ρ
k
+ α3δ
k
(x1 −x∗
1)(x3 −x∗
3) −ρ
k (α2 + α3)(x2 −x∗
2)(x3 −x∗
3) + α1b(x1 −x∗
1)
x2
x1
−x∗
2
x∗
1
+ α1x∗
1σ2
1
2
+ α2x∗
2σ2
2
2
+ α3x∗
3σ2
3
2
. (19) (19) Taking α1 = ak −1 , α2 = ak + 1, and α3 = 1, therefore, LV5 ≤−((ak −1)(1 −ρ) −δ)
k
(x1 −x∗
1)2 −(ak + akρ + 1)
k
(x2 −x∗
2)2 −(1 −ρ −δ −2akρ)
k
(x3 −x∗
3)2
+ b(b2k
4c + x∗
1) + (ak −1)x∗
1σ2
1
2
+ (ak + 1)x∗
2σ2
2
2
+ x∗
3σ2
3
2
. (20) (20) Following [18,44–46], when Following [18,44–46], when m < min
((ak −1)(1 −ρ) −δ)
k
(x∗
1)2, (ak + akρ + 1)
k
(x∗
2)2, (1 −ρ −δ −2akρ)
k
(x∗
3)2
, then the ellipsoid −((ak −1)(1 −ρ) −δ)
k
(x1 −x∗
1)2 −(ak + akρ + 1)
k
(x2 −x∗
2)2 −(1 −ρ −δ −2akρ)
k
(x3 −x∗
3)2 + δ)(x1 −x∗
1)2 −(ak + akρ + 1)
k
(x2 −x∗
2)2 −(1 −ρ −δ −2akρ)
k
(x3 −x∗
3)2 + m = 0, −((ak −1)(1 −ρ) −δ)
k
(x1 −x∗
1)2 −(ak + akρ + 1)
k
(x2 −x∗
2)2 −(1 −ρ −δ −2akρ)
k
(x3 −x∗
3)2 + m = 0, lies entirely in R3+. One can take U1 to be a neighborhood of the ellipsoid, which satisfies
¯U1 ⊆R3+; hence, LV5 < 0 for (x1, x2, x3) ∈R3+ \ ¯U1. This implies that the first condition H1
of the method of Khasminskii [41] is satisfied. Therefore, The second step is to validate condition H2
of Lemma 1. The diffusion matrix A1 of the stochastic Hantavirus infection model (3) is
as follows
2 2 A1 =
σ2
1 x2
1
0
0
0
σ2
2 x2
2
0
0
0
σ2
3 x2
3
. Following [37,46,47], we choose M0 = min
σ2
1 x2
1, σ2
2 x2
2, σ2
3 x2
3
; then, one can find a
positive number M0 such that 3
∑
i,j=1
aij(x1, x2, x3)ξiξj = σ2
1 x2
1ξ2
1 + σ2
2 x2
2ξ2
2 + σ2
3 x2
3ξ2
3 ≥M0|ξ2|, for all ξ = (ξ1, ξ2, ξ3) ∈R3 and (x1, x2, x3) ∈U1. This implies condition H2 in Lemma 1 is
satisfied. As a result, the stochastic Hantavirus infection model (3) has an ergodic stationary
distribution for any given positive initial values. for all ξ = (ξ1, ξ2, ξ3) ∈R3 and (x1, x2, x3) ∈U1. This implies condition H2 in Lemma 1 is
satisfied. As a result, the stochastic Hantavirus infection model (3) has an ergodic stationary
distribution for any given positive initial values. Remark 2: If we assume y(t) = x1(t) + x2(t) and add the first and second equations
of system (3), one obtains dy(t) =
(b −c)y −1
k y2 −ρ y x3
k
dt + σ1x1 dB1 + σ2x2 dB2
≤(b −c) y(1 −
y
k(b −c))dt + σ1x1 dB1 + σ2x2 dB2. (21) (21) Mathematics 2022, 10, 3756 10 of 15 10 of 15 According to Liu and Wang [48], if the intensities of the white noises are sufficiently
small and b −c > σ2
1
2 + σ2
2
2 , then there is a stationary distribution to the following equation
for positive initial values dy(t) = (b −c) y(1 −
y
k(b −c))dt + σ1 y dB1 + σ2 y dB2,
(22) (22) and it has an ergodic property. From the third equation of the stochastic Hantavirus
infection system (3), one obtains dx3(t) ≤(β −γ)x3
1 −
x3
k(β −γ)
dt + σ3x3 dB3,
(23) (23) According to [49,50], x3(t) neither reaches zero nor infinity in finite time, and provided
(β −γ) > σ2
3
2 , the process has been shown to have a stationary distribution. Therefore, Moreover, it
has been shown that 0 < lim
t→∞inf x3(t) ≤lim
t→∞sup x3(t) < ∞
almostsurely. 4. Numerical Simulations The population of the infected y(t) will die
away when k < kc. The Hantavirus disease will spread and increase in rodents if k > kc. Figure 4 represents the dynamical behavior of the Abramson model (2) and verifies the
statement of [1]. For k = 20, the free Hantavirus equilibrium point E = (8, 0, 0) is locally
asymptotically stable in the deterministic model. while the solutions of the stochastic where ϵij, (i, j = 1, 2, 3) are independent random Gaussian variables N(0, 1), and h is
a positive time increment. In the stochastic Hantavirus infection model (3), if one gradually
increases the values of σi and keeps the remaining parameters unchanged, the fluctuations
become larger around the positive equilibrium point for the values of σi = 0.2, as shown in
Figure 1. The infected mice y(t) are represented by the black line when (σi = 0), as seen
in Figure 1. The conditions of Theorem 4 for the given parameters are verified, and the
populations will be extinct with probability one, if b < c and β < σ3
3
2 + γ as indicated in
Figure 2, when b = 0.55 and β = 0.5. Moreover, the trivial solution of the Hantavirus
infection model (3) is stochastically asymptotically stable in probability if the conditions
of Theorem 5 are verified, i.e., σ2
1
2 + b < c, σ2
3
2 + β < γ, and ( σ2
1
2 + b −c)( σ2
2
2 −c) > b2
4 as
indicated in Figure 3. The stochastic form of the Abramson model (2) is recovered by
setting ρ = 0 and ignoring the third equation of system (3). Following [2,51], there is
a critical value kc for the carrying capacity k. The population of the infected y(t) will die
away when k < kc. The Hantavirus disease will spread and increase in rodents if k > kc. Figure 4 represents the dynamical behavior of the Abramson model (2) and verifies the
statement of [1]. For k = 20, the free Hantavirus equilibrium point E = (8, 0, 0) is locally
asymptotically stable in the deterministic model. while the solutions of the stochastic where ϵij, (i, j = 1, 2, 3) are independent random Gaussian variables N(0, 1), and h is
a positive time increment. 4. Numerical Simulations In order to demonstrate the above theoretical results for the stochastic Hantavirus
system, we use the following parameters [2,51]: a = 0.1; b = 1; c = 0.6; β = 1; γ = 0.5; ρ = 0.2; δ = 0.1; k = 50. To give some numerical finding to the stochastic Hantavirus system (3), we use the
Milstein method mentioned in [52,53]. The stochastic Hantavirus infection system (3)
reduces to the following discrete system x1(j+1) = x1j + h
b(x1j + y1j) −cx1j −x1j
k (x1j + x2j + ρx3j) −ax1jx2j
+ σ1x1j
√
hϵ1j + σ2
1
2 x1j
h
ϵ2
1j −1
i
h
x2(j+1) = x2j + h
ax1jx2j −x2j
k (x1j + x2j + ρx3j) −cx2j
+ σ2x2j
√
hϵ2j + σ2
2
2 x2j
h
ϵ2
2j −1
i
h
x3(j+1) = x3j + h
(β −γ)x3j −x3j
k
x3j + δ(x1j + x2j)
+ σ3x3j
√
hϵ3j + σ2
3
2 x3j
h
ϵ2
3j −1
i
h,
(24) (24) where ϵij, (i, j = 1, 2, 3) are independent random Gaussian variables N(0, 1), and h is
a positive time increment. In the stochastic Hantavirus infection model (3), if one gradually
increases the values of σi and keeps the remaining parameters unchanged, the fluctuations
become larger around the positive equilibrium point for the values of σi = 0.2, as shown in
Figure 1. The infected mice y(t) are represented by the black line when (σi = 0), as seen
in Figure 1. The conditions of Theorem 4 for the given parameters are verified, and the
populations will be extinct with probability one, if b < c and β < σ3
3
2 + γ as indicated in
Figure 2, when b = 0.55 and β = 0.5. Moreover, the trivial solution of the Hantavirus
infection model (3) is stochastically asymptotically stable in probability if the conditions
of Theorem 5 are verified, i.e., σ2
1
2 + b < c, σ2
3
2 + β < γ, and ( σ2
1
2 + b −c)( σ2
2
2 −c) > b2
4 as
indicated in Figure 3. The stochastic form of the Abramson model (2) is recovered by
setting ρ = 0 and ignoring the third equation of system (3). Following [2,51], there is
a critical value kc for the carrying capacity k. 4. Numerical Simulations In the stochastic Hantavirus infection model (3), if one gradually
increases the values of σi and keeps the remaining parameters unchanged, the fluctuations
become larger around the positive equilibrium point for the values of σi = 0.2, as shown in
Figure 1. The infected mice y(t) are represented by the black line when (σi = 0), as seen
in Figure 1. The conditions of Theorem 4 for the given parameters are verified, and the populations will be extinct with probability one, if b < c and β < σ3
3
2 + γ as indicated in
Figure 2, when b = 0.55 and β = 0.5. Moreover, the trivial solution of the Hantavirus
infection model (3) is stochastically asymptotically stable in probability if the conditions of Theorem 5 are verified, i.e., σ2
1
2 + b < c, σ2
3
2 + β < γ, and ( σ2
1
2 + b −c)( σ2
2
2 −c) > b2
4 as
indicated in Figure 3. The stochastic form of the Abramson model (2) is recovered by
setting ρ = 0 and ignoring the third equation of system (3). Following [2,51], there is
a critical value kc for the carrying capacity k. The population of the infected y(t) will die
away when k < kc. The Hantavirus disease will spread and increase in rodents if k > kc. Figure 4 represents the dynamical behavior of the Abramson model (2) and verifies the
statement of [1]. For k = 20, the free Hantavirus equilibrium point E = (8, 0, 0) is locally
asymptotically stable in the deterministic model. while the solutions of the stochastic Mathematics 2022, 10, 3756 11 of 15 11 of 15 Hantavirus infection model (3) oscillate around the equilibrium point, which coincides
with Theorem 6. The oscillation amplitude will be lim
t→∞sup 1
t E
Z t
0
h
(x1(u) −x0)2 + x2(u)2 + x3(u)2i
du ≤80 σ2
1 + 388 α2α2
1 + 96. The histograms of the density function for the Hantavirus infection model (3) are
shown in Figure 5, and the system (3) has a unique stationary distribution and has an
ergodic property according to the conditions of Theorem 7. 4. Numerical Simulations The density function of susceptible mice of the Hantavirus infection system (3). 5. Conclusions Figure 5. The density function of susceptible mice of the Hantavirus infection system (3). 4. Numerical Simulations The histograms of the density function for the Hantavirus infection model (3) are
shown in Figure 5, and the system (3) has a unique stationary distribution and has an
ergodic property according to the conditions of Theorem 7. ergodic property according to the conditions of Theorem 7. Figure 1. The stochastic Hantavirus system (3) with respect to σi = 0 and σi = 0.2. Figure 2. The extinct behavior of the solutions to the Hantavirus infection system (3). Figure 1. The stochastic Hantavirus system (3) with respect to σi = 0 and σi = 0.2. Figure 1. The stochastic Hantavirus system (3) with respect to σi = 0 and σi = 0.2. Figure 2. The extinct behavior of the solutions to the Hantavirus infection system (3). Figure 1. The stochastic Hantavirus system (3) with respect to σi = 0 and σi = 0.2. Figure 2. The extinct behavior of the solutions to the Hantavirus infection system (3). 12 of 15 12 of 15 Mathematics 2022, 10, 3756 Figure 3. The stochastic trajectories for the trivial solutions of the stochastic Hantavirus infection
system (3). Figure 3. The stochastic trajectories for the trivial solutions of the stochastic Hantavirus infection
system (3). 0
100
200
300
400
t
0
5
10
x1,x2
k=20 and σi =0
x1
x2
x
x 0
100
200
300
400
t
0
5
10
15
x1,x2
k=20 and σi =0.1
x1
x2 0
100
200
300
400
t
0
5
10
x1,x2
k=20 and σi =0
x1
x2
0
100
200
300
400
t
0
5
10
15
x1,x2
k=20 and σi =0.1
x1
x2
0
100
200
300
400
t
0
5
10
x1,x2
k=30 and σi =0
x1
x2
0
100
200
300
400
t
0
5
10
15
x1,x2
k=30 and σi =0.1
x1
x2
Figure 4. The stochastic behavior of the Abramson system for k = 20, 30, and σi = 0, 0.1. 0
100
200
300
400
t
0
5
10
x1,x2
k=30 and σi =0
x1
x2
x
x 0
100
200
300
400
t
0
5
10
15
1, 2
k=30 and σi =0.1
x1
x2 Figure 4. The stochastic behavior of the Abramson system for k = 20, 30, and σi = 0, 0.1. 13 of 15 Mathematics 2022, 10, 3756 Figure 5. The density function of susceptible mice of the Hantavirus infection system (3). 5. Conclusions Figure 5. 5. Conclusions This paper mainly analyzed a stochastic Hantavirus infection model. The existence
and boundedness of the positive solution of the stochastic Hantavirus infection model were
derived. The conditions for the extinction of the Hantavirus infection from the stochastic
system were obtained using stochastic analysis tools. Furthermore, the criteria for the
presence of a unique ergodic stationary distribution for the Hantavirus infection model
were established using a suitable Lyapunov function. The numerical Milstein method was
used to simulate the significance of environmental noise in the Hantavirus infection model. When intensities of fluctuation σi = 0, one can obtain the results for the deterministic
model introduced by Peixoto [2]. One can note that the movement of rodents cannot be
neglected; consequently, it is interesting to investigate the spatial effects for the stochastic
Hantavirus infection model, which will be future work. Moreover, the authors wish to
consider the fractionalization of the stochastic Hantavirus infection model given that there
is much current research and example publications in this area, with regard to the SIR
model, for example [54]. In future work, the authors wish to conduct a detailed analysis of
the stochastic Hantavirus infection model using boundary methods as introduced in the
following papers [44,55–61]. Author Contributions: Data curation, M.E.-S.; Formal analysis, Y.A. All authors have read and
agreed to the published version of the manuscript. Funding: This research received no external funding. Acknowledgments: The researchers would like to thank the Deanship of Scientific Research, Qassim
University, for funding the publication of this project. Acknowledgments: The researchers would like to thank the Deanship of Scientific Research, Qassim
University, for funding the publication of this project. Conflicts of Interest: The authors declare no conflict of interest. Conflicts of Interest: The authors declare no conflict of interest. 1.
Abramson, G.; Kenkre, V.M. Spatiotemporal patterns in the Hantavirus infection. Phys. Rev. E 2002, 66, 011912. [CrossRef]
[PubMed]
2
P i
t
I D Ab
G Th
ff
t f bi di
it
th H
t
i
i
ti
E
l
2006 87 873 879 [C
R f] g
gy
g g
g
4.
Yusof, F.M.; Mohd, M.H.; Yatim, Y.M.; Ismail, A.I.M. Effects of Biotic Interactions, Abiotic Environm
Spread of Hantavirus Infection. MATEMATIKA Malays. J. Ind. Appl. Math. 2020, 36 , 1–14. 1.
Abramson, G.; Kenkre, V.M. Spatiotemporal patterns in the Hantavirus infection. Phys. Rev. E 2002, 66, 011912. [CrossRef]
[PubMed]
2.
Peixoto, I.D.; Abramson, G. The effect of biodiversity on the Hantavirus epizootic. Ecology 2006, 87, 873–879. [CrossRef]
3
Solomon E ; Berg L ; Martin D W Biology; Cengage Learning: Boston MA USA 2010 2.
Peixoto, I.D.; Abramson, G. The effect of biodiversity on the Hantavirus epizootic. Ecology 2006, 87, 87
3.
Solomon, E.; Berg, L.; Martin, D.W. Biology; Cengage Learning: Boston, MA, USA, 2010. e
oto,
;
b a
so , G
e e ect o b od
e s ty o
t e
a ta
us ep oot c
gy 006
3.
Solomon, E.; Berg, L.; Martin, D.W. Biology; Cengage Learning: Boston, MA, USA, 2010. 2.
Peixoto, I.D.; Abramson, G. The effect of biodiversity on the Hantavirus epizootic. Ecology 2006, 87, 87
3
S l
E B
L M
ti
D W Bi l
C
L
i
B
t
MA USA 2010 g
gy
g g
g
Mohd, M.H.; Yatim, Y.M.; Ismail, A.I.M. Effects of Biotic Interactions, Abiotic Environments and Harvesting
antavirus Infection. MATEMATIKA Malays. J. Ind. Appl. Math. 2020, 36 , 1–14. References Modeling and optimal control on the spread of Hantavirus infection. Mathematics 2019,
7, 1192. [CrossRef] 16. Moustafa, M.; Mohd, M.H.; Ismail, A.I.; Abdullah, F.A. Dynamical Analysis of a Fractional-Order Hantavirus Infection Model. Int. J. Nonlinear Sci. Numer. Simul. 2019, 21, 171–181. [CrossRef] 17. Moustafa, M.; Abdullah, F.A.; Shafie, S.; Ismail, Z. Dynamical behavior of a fractional-order Hantavirus infection model
incorporating harvesting. Alex. Eng. J. 2022, 61, 11301–11312. [CrossRef] p
g
g
g
18. Wei, C.; Liu, J.; Zhang, S. Analysis of a stochastic eco-epidemiological model with modified Leslie
Adv. Differ. Equ. 2018, 2018, 1–17. [CrossRef] 18. Wei, C.; Liu, J.; Zhang, S. Analysis of a stochastic eco epidemiological model with modified Leslie Gower functional response. Adv. Differ. Equ. 2018, 2018, 1–17. [CrossRef]
19. May, R.M. Stability and complexity in model ecosystems. In Stability and Complexity in Model Ecosystems; Princeton University ff
q
,
,
[
]
19. May, R.M. Stability and complexity in model ecosystems. In Stability and Complexity in Model Ecosystems; Princeton University
Press: Princeton, NJ, USA, 2019. 19. May, R.M. Stability and complexity in model ecosystems. In Stability and Complexity in Model Ecos
Press: Princeton, NJ, USA, 2019. 20. Liu, M.; Wang, K.; Wu, Q. Survival analysis of stochastic competitive models in a polluted environment and stochastic competitive
exclusion principle. Bull. Math. Biol. 2011, 73, 1969–2012. [CrossRef] p
p
21. Xu, C.; Ren, G.; Yu, Y. Extinction analysis of stochastic predator–prey system with stage structure and crowley–martin functional
response. Entropy 2019, 21, 252. [CrossRef] 22. Song, G. Dynamics of a stochastic population model with predation effects in polluted environments. Adv. Differ. Equ. 2021,
2021, 1–19. [CrossRef] 23. Mu, Y.; Lo, W.C. Stochastic dynamics of populations with refuge in polluted turbidostat. Chaos Solitons Fractals 2021, 147, 110963. [CrossRef] 24. Wang, Z.; Deng, M.; Liu, M. Stationary distribution of a stochastic ratio-dependent predator-prey sy
Chaos Solitons Fractals 2021, 142, 110462. [CrossRef] 25. Salman, S.; Yousef, A.; Elsadany, A. Dynamic behavior and bifurcation analysis of a deterministic and stochastic coupled logistic
map system. Int. J. Dyn. Control 2022, 10, 69–85. [CrossRef] p y
J
y
26. Lei, Q.; Yang, Z. Dynamical behaviors of a stochastic SIRI epidemic model. Appl. Anal. 2017, 96, 2758–2770. [CrossRef]
27
Liu Q ; Jiang D ; Hayat T ; Alsaedi A ; Ahmad B A stochastic SIRS epidemic model with logistic growth and general nonlinear 26. Lei, Q.; Yang, Z. References 14 of 15 14 of 15 Mathematics 2022, 10, 3756 5. Abdullah, F.A.; Ismail, A.I. Simulations of the spread of the Hantavirus using fractional differential equations. Matematika 2011,
27, 149–158. 6. Chen, M.; Clemence, D.P. Analysis of and numerical schemes for a mouse population model in Hantavirus epidemics. J. Differ. Equ. Appl. 2006, 12, 887–899. [CrossRef] q
pp
7. Gedeon, T.; Bodelón, C.; Kuenzi, A. Hantavirus transmission in sylvan and peridomestic environments. Bull. Math. Biol. 2010,
72, 541–564. [CrossRef] 8. Allen, L.J.S.; Wesley, C.L.; Owen, R.D.; Goodin, D.G.; Koch, D.; Jonsson, C.B.; Chu, Y.; Hutchinson, J.M.S.; Paige, R.L. A habitat-
based model for the spread of Hantavirus between reservoir and spillover species. J. Theor. Biol. 2009, 260, 510–522. [CrossRef]
9. Rida, S.Z.; Abd-elradi, A.S.; Arafa, A.; Khalil, M. The effect of the environmental parameter on the Hantavirus infection through
a fractional-order SI model. Int. J. Basic Appl. Sci. 2012, 1, 88–99. [CrossRef] 8. Allen, L.J.S.; Wesley, C.L.; Owen, R.D.; Goodin, D.G.; Koch, D.; Jonsson, C.B.; Chu, Y.; Hutchinson, J.M.S.; Paige, R.L. A habitat-
based model for the spread of Hantavirus between reservoir and spillover species. J. Theor. Biol. 2009, 260, 510–522. [CrossRef]
9. Rida, S.Z.; Abd-elradi, A.S.; Arafa, A.; Khalil, M. The effect of the environmental parameter on the Hantavirus infection through 9. Rida, S.Z.; Abd-elradi, A.S.; Arafa, A.; Khalil, M. The effect of the environmental parameter on the Hantavirus infection through
a fractional-order SI model. Int. J. Basic Appl. Sci. 2012, 1, 88–99. [CrossRef] pp
M.A.; Abramson, G.; Bishop, A.R.; Kenkre, V.M. Simulations in the mathematical modeling of the spr
us. Phys. Rev. E 2002, 66, 041908. [CrossRef] 10. Aguirre, M.A.; Abramson, G.; Bishop, A.R.; Kenkre, V.M. Simulations in the mathematical mo
Hantavirus. Phys. Rev. E 2002, 66, 041908. [CrossRef] 11. Buceta, J.; Escudero, C.; Rubia, F.J.; Lindenberg, K. Outbreaks of Hantavirus induced by seasonality. Phys. Rev. E 2004, 69, 021906. [CrossRef] 12. Karim, M.F.A.; Ismail, A.I.M.; Ching, H.B. Cellular automata modelling of Hantarvirus infection. Chaos Solitons Fractals 2009,
41, 2847–2853. [CrossRef] G. The criticality of the Hantavirus infected phase at Zuni. arXiv 2004, arXiv:q-bio/0407003. 13. Abramson, G. The criticality of the Hantavirus infected phase at Zuni. arXiv 2004, arXiv:q-bio/040700 14. Goh, S.M.; Ismail, A.I.M.; Noorani, M.S.M.; Hashim, I. Dynamics of the Hantavirus infection through variational iteration method. Nonlinear Anal. Real World Appl. 2009, 10, 2171–2176. [CrossRef] pp
,
,
[
]
15. Yusof, F.M.; Abdullah, F.A.; Ismail, A.I. References Dynamical behaviors of a stochastic SIRI epidemic model. Appl. Anal. 2017, 96, 2758–2770. [CrossRef]
27. Liu, Q.; Jiang, D.; Hayat, T.; Alsaedi, A.; Ahmad, B. A stochastic SIRS epidemic model with logistic growth and general nonlinear
incidence rate. Phys. A Stat. Mech. Its Appl. 2020, 551, 124152. [CrossRef] 28. Li, Q.; Cong, F.; Liu, T.; Zhou, Y. Stationary distribution of a stochastic HIV model with two infective stages. Phys. A Stat. Mech. Its Appl. 2020, 554, 124686. [CrossRef] 29. Khan, A.; Hussain, G.; Yusuf, A.; Usman, A.H.; et al. A hepatitis stochastic epidemic model with acute and chronic stages. Adv. Differ. Equ. 2021, 2021, 181. [CrossRef] ff
q
30. Wang, X.; Wang, C.; Wang, K. Extinction and persistence of a stochastic SICA epidemic model with standard incidence rate for
HIV transmission. Adv. Differ. Equ. 2021, 2021, 260. 31. Wang, X.; Tan, Y.; Cai, Y.; Wang, K.; Wang, W. Dynamics of a stochastic HBV infection model with cell-to-cell transmission and
immune response. Math. Biosci. Eng. 2021, 18, 616–642. [CrossRef] 32. Lan, G.; Yuan, S.; Song, B. The impact of hospi
J. Frankl. Inst. 2021, 358, 2405–2433. [CrossRef] 32. Lan, G.; Yuan, S.; Song, B. The impact of hospital resources and environmental perturbations to the dynamics of SIRS model. J. Frankl. Inst. 2021, 358, 2405–2433. [CrossRef] 33. Ikram, R.; Khan, A.; Zahri, M.; Saeed, A.; Yavuz, M.; Kumam, P. Extinction and stationary distribution
epidemic model with time-delay. Comput. Biol. Med. 2022, 141, 105115. [CrossRef] Zahri, M.; Saeed, A.; Yavuz, M.; Kumam, P. Extinction and stationary distribution of a stochastic COVID-19
h time-delay. Comput. Biol. Med. 2022, 141, 105115. [CrossRef] 34. Johari, A.; Khodaparast, A. Analytical stochastic analysis of seismic stability of infinite slope. Soil Dyn. Earthq. Eng. 2015,
79, 17–21. [CrossRef] 15 of 15 15 of 15 Mathematics 2022, 10, 3756 35. Gholampour, A.; Johari, A. Reliability analysis of a vertical cut in unsaturated soil using sequential Gaussian simulation. Sci. Iran. 2019, 26, 1214–1231. [CrossRef] 36. Hu, C.; Song, D.; Chen, Z. Analytical stochastic analysis of rock wedge stability using a JDRV method considering the residual
factor as a random variable. Geomat. Nat. Hazards Risk 2020, 11, 2079–2094. [CrossRef] 37. Li, L.; Zhao, W. Deterministic and stochastic dynamics of a modified Leslie-Gower prey-predator system with simplified
Holling-type IV scheme. Math. Biosci. Eng. 2021, 18, 2813–2831. [CrossRef] 38. Li, J.; Shan, M.; Banerjee, M.; Wang, W. References Stochastic dynamics of feline immunodeficiency virus within cat populations. J. Frankl. Inst. 2016, 353, 4191–4212. [CrossRef] 39. Mao, X. Stochastic Differential Equations and Applications; Elsevier: Amsterdam, The Netherlands, 2007. A
ld
S
h
i
iff
i l
i
W l
Y
k
Y
SA 39. Mao, X. Stochastic Differential Equations and Applications; Elsevier: Amsterdam, The Netherlands, 2007. 40. Arnold, L. Stochastic Differential Equations; Wiley : New York, NY, USA, 1974. 41. Khasminskii, R. Stochastic Stability of Differential Equations; Springer Science & Business Media: Berlin, G 41. Khasminskii, R. Stochastic Stability of Differential Equations; Springer Science & Business Media: Berlin, Germany, 2011; Volume 66. 42. Caraballo, T.; Kloeden, P.E. The persistence of synchronization under environmental noise. Proc. R. Soc. A Math. Phys. Eng. Sci. 2005, 461, 2257–2267. [CrossRef] y f
ff
q
p
g
y
42. Caraballo, T.; Kloeden, P.E. The persistence of synchronization under environmental noise. Proc. R. Soc. A Math. Phys. Eng. Sci. 2005, 461, 2257–2267. [CrossRef] 43. Ji, C.; Jiang, D.; Liu, H.; Yang, Q. Existence, uniqueness and ergodicity of positive solution of mutualism system with stochastic
perturbation. Math. Probl. Eng. 2010, 2010, 684926. [CrossRef] g
P.; Wang, B. Dynamics of cholera epidemic models in fluctuating environments. Stochastics Dyn. 2021
Ref] p
g
44. Phan, T.A.; Tian, J.P.; Wang, B. Dynamics of cholera epidemic models in fluctuating environments
21, 2150011. [CrossRef] 45. Li, S.; Wang, X. Analysis of a stochastic predator-prey model with disease in the predator and Beddington-DeAngelis functional
response. Adv. Differ. Equ. 2015, 2015, 224. [CrossRef] p
ff
q
[
]
46. Huang, Y.; Shi, W.; Wei, C.; Zhang, S. A stochastic predator–prey model with Holling II increasing function in the predator. J. Biol. Dyn. 2021, 15, 1–18. [CrossRef] 47. Chen, Y.; Zhao, W. Dynamical analysis of a stochastic SIRS epidemic model with saturating contact rate. Math. Biosci. Eng. 2020,
17, 5925–5943. [CrossRef] 48. Liu, M.; Wang, K. Stationary distribution, ergodicity and extinction of a stochastic generalized logistic system. Appl. Math. Lett. 2012, 25, 1980–1985. [CrossRef] 49. Alvarez, L.H.; Shepp, L.A. Optimal harvesting of stochastically fluctuating populations. J. Math. [CrossRef] 49. Alvarez, L.H.; Shepp, L.A. Optimal harvesting of stochastically fluctuating populations. J. Math. Biol. 1998, 37, 155–177. [CrossRef]
50
L
J W
K Al
f
h
i
i
l
i
d l
J M th A
l A
l 2015 422 675 683 [C
R f] [
]
50. Lv, J.; Wang, K. References Almost sure permanence of stochastic single species models. J. Math. Anal. Appl. 2015, 422, 675–683. [CrossRef]
51. Yusof, F.; Ismail, A.; Ali, N. Effect of predators on the spread of hantavirus infection. Sains Malays. 2014, 43, 1045–1051. 50. Lv, J.; Wang, K. Almost sure permanence of stochastic single species models. J. Math. Anal. Appl. 2 Wang, K. Almost sure permanence of stochastic single species models. J. Math. Anal. Appl. 2015, 422, 675–6
, F.; Ismail, A.; Ali, N. Effect of predators on the spread of hantavirus infection. Sains Malays. 2014, 43, 1045 51. Yusof, F.; Ismail, A.; Ali, N. Effect of predators on the spread of hantavirus infection. Sains Malays. 52. Higham, D.J. An algorithmic introduction to numerical simulation of stochastic differential equations. SIAM Rev. 2001,
43, 525–546. [CrossRef] 53. Alnafisah, Y. The implementation of Milstein scheme in two-dimensional SDEs using the Fourier method. In Abstract and Applied
Analysis; Hindawi: London, UK, 2018; Volume 2018. 54. Djenina, N.; Ouannas, A.; Batiha, I.M.; Grassi, G.; Oussaeif, T.E.; Momani, S. A Novel Fractional-Order Discrete SIR Model for
Predicting COVID-19 Behavior. Mathematics 2022, 10, 2224. [CrossRef] 55. Hening, A.; Nguyen, D.H. Coexistence and extinction for stochastic Kolmogorov systems. Ann. Appl. Probab. 2018, 28, 1893–1942. [CrossRef] 56. Benaim, M. Stochastic persistence. arXiv 2018, arXiv:1806.08450. 56. Benaim, M. Stochastic persistence. arXiv 2018, arXiv:1806.08450. 57. Phan, T.A.; Tian, J.P. Basic stochastic model for tumor virotherapy. Math. Biosci. Eng. 2020, 17, 4271 57. Phan, T.A.; Tian, J.P. Basic stochastic model for tumor virotherapy. Math. Biosci. Eng. 2020, 17, 4271–4294. [CrossRef] [PubMed]
58. Phan, T.A. Stochastic Modeling for Some Biological and Medical Problems. Ph.D. Thesis, New Mexico State University,
Las Cruces, NM, USA, 2020. 58. Phan, T.A. Stochastic Modeling for Some Biological and Medical Problems. Ph.D. Thesis, New Mexico State University,
Las Cruces, NM, USA, 2020. 59. Phan, T.A.; Tian, J.P. Hopf bifurcation without parameters in deterministic and stochastic modeling of cancer virotherapy, part I. J. Math. Anal. Appl. 2022, 514, 126278. [CrossRef] pp
60. Phan, T.A.; Tian, J.P. Hopf bifurcation without parameters in deterministic and stochastic modeling of cancer virotherapy, part II. J. Math. Anal. Appl. 2022, 515, 126444. [CrossRef] 60. Phan, T.A.; Tian, J.P. Hopf bifurcation without parameters in deterministic and stochastic modeling of cancer virotherapy, part II. J. Math. Anal. Appl. 2022, 515, 126444. [CrossRef] 61. Phan, T.A.; Wang, S.; Tian, J.P. Analysis of a new stochastic Gompertz diffusion model for untreated human glioblastomas. References Stochastics Dyn. 2022, 2022, 2250019. [CrossRef] 61. Phan, T.A.; Wang, S.; Tian, J.P. Analysis of a new stochastic Gompertz diffusion model for untreated human glioblastomas. Stochastics Dyn. 2022, 2022, 2250019. [CrossRef]
|
https://openalex.org/W2586080413
|
https://europepmc.org/articles/pmc5301248?pdf=render
|
English
| null |
Strain Gated Bilayer Molybdenum Disulfide Field Effect Transistor with Edge Contacts
|
Scientific reports
| 2,017
|
cc-by
| 7,161
|
Yu Chai1, Shanshan Su2, Dong Yan3, Mihrimah Ozkan2, Roger Lake2 & Cengiz S. Ozkan1,4 Silicon nitride stress capping layer is an industry proven technique for increasing electron mobility
and drive currents in n-channel silicon MOSFETs. Herein, the strain induced by silicon nitride is firstly
characterized through the changes in photoluminescence and Raman spectra of a bare bilayer MoS2
(Molybdenum disulfide). To make an analogy of the strain-gated silicon MOSFET, strain is exerted to a
bilayer MoS2 field effect transistor (FET) through deposition of a silicon nitride stress liner that warps
both the gate and the source-drain area. Helium plasma etched MoS2 layers for edge contacts. Current
on/off ratio and other performance metrics are measured and compared as the FETs evolve from back-
gated, to top-gated and finally, to strain-gated configurations. While the indirect band gap of bilayer
MoS2 at 0% strain is 1.25 eV, the band gap decreases as the tensile strain increases on an average of
~100 meV per 1% tensile strain, and the decrease in band gap is mainly due to lowering the conduction
band at K point. Comparing top- and strain-gated structures, we find a 58% increase in electron mobility
and 46% increase in on-current magnitude, signalling a benign effect of tensile strain on the carrier
transport properties of MoS2. Strain is a critical ingredient in modern transistor scaling. For Intel process technologies, the electron mobility
decreased from 400 to 120 cm2/Vs when the industry migrated from 0.80 μm to 0.13 μm technology node due
to the large vertical electric field1. Strain engineering has proven an effective route for mobility enhancement
by modifying the carrier effective mass and mean scattering time2. For transistors with sub-100 nm gate length,
strained silicon increased the saturated MOSFETs drive currents by 10–20% and mobility by >50%, and later
ramped into high volume manufacturing on high performance microprocessors in the 90 nm logic technology3. The electron and hole mobility of silicon responds differently to externally applied stress. Longitudinal tensile
stress along transistor channel improves electron mobility but degrades hole mobility4–6. p-MOSFET features a
compressively strained SiGe film embedded in the source and drain regions7. The mismatch in the SiGe to Si lat-
tice causes the channel to be under a uniaxial compressive strain, leading to significantly improved hole mobility8. For n-MOSFET, a post-salicide tensile silicon nitride capping layer was deposited on top of the transistor gate,
wrapping both the gate and source drain area7. www.nature.com/scientificreports www.nature.com/scientificreports www.nature.com/scientificreports Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 Strain Gated Bilayer Molybdenum
Disulfide Field Effect Transistor with
Edge Contacts received: 05 May 2016
accepted: 07 December 2016
Published: 10 February 2017 received: 05 May 2016
accepted: 07 December 2016
Published: 10 February 2017 Yu Chai1, Shanshan Su2, Dong Yan3, Mihrimah Ozkan2, Roger Lake2 & Cengiz S. Oz Yu Chai1, Shanshan Su2, Dong Yan3, Mihrimah Ozkan2, Roger Lake2 & Cengiz S. Ozkan1,4 As a tensile stressor inside the nitride film tends to shrink, the
stressor on the source and drain pulls apart the ends of the transistor channel and mainly produce a longitudinal
tensile strain in the n-MOSFET channel2. For three-dimensional semiconductor, the ultimate strain exertion is limited by both bulk defects and surface
imperfections9. Transition metal dichalcogenides (TMDCs) are more suitable for strain engineering for two rea-
sons: negligible bulk defects because of a thickness of only a few atomic planes and a fully-terminated surface,
eliminating fab processing steps that usually targeted at the passivation of dangling bonds. A breaking strain up to
11% for MoS2
10 has been proved experimentally, whereas bulk silicon can be strained only 1.2% before fracture9.h 2
p
p
y
y
Theoretical studies have predicted that when an external tensile stress is applied, the electronic structure of
monolayer MoS2 undergoes a series of variations: first, a direct-to-indirect band gap transition when the lat-
tice constant is just slightly lengthened; second, a more drastic semiconductor-to-metal transition when the lat-
tice constant is increased by more than 9.8%11. In particular, the tensile strain reduces the gap energy and the
effective masses while the compressive strain enhances them11,12. Majority of experimental demonstration of the 1Materials Science and Engineering Program, University of California, Riverside, CA 92521 USA. 2Department of
Electrical and Comp. Engineering, University of California, Riverside, CA 92521 USA. 3Center for Nanoscale Science &
Engineering, University of California, Riverside, CA 92521 USA. 4Department of Mechanical Engineering, University
of California, Riverside, CA 92521 USA. Correspondence and requests for materials should be addressed to C.S.O. (email: cozkan@engr.ucr.edu) Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 1 www.nature.com/scientificreports/ www.nature.com/scientificreports/ Figure 1. Photoluminescence and Raman spectra of bi-layer MoS2 with locally deposited silicon nitride. (a) the as-prepared bi-layer MoS2 on Si/SiO2 substrate; (b) the same sample with only region 2 covered by
silicon nitride, region 1 and 3 serve as control groups; (c to e) photoluminescence and (f to h) Raman spectra
of all three regions, spectra in black color were taken from the as-prepared sample; red color, post-nitride
deposition process. The black arrows indicate the direction of peak shift. Figure 1. Photoluminescence and Raman spectra of bi-layer MoS2 with locally deposited silicon nitride. ( ) h
d b l
S
S /S O
b
(b) h
l
h
l
d b Figure 1. Yu Chai1, Shanshan Su2, Dong Yan3, Mihrimah Ozkan2, Roger Lake2 & Cengiz S. Ozkan1,4 Photoluminescence and Raman spectra of bi-layer MoS2 with locally deposited silicon nitride. (a) the as-prepared bi-layer MoS2 on Si/SiO2 substrate; (b) the same sample with only region 2 covered by
silicon nitride, region 1 and 3 serve as control groups; (c to e) photoluminescence and (f to h) Raman spectra
of all three regions, spectra in black color were taken from the as-prepared sample; red color, post-nitride
deposition process. The black arrows indicate the direction of peak shift. strain effect on MoS2 employs standard three-point or four-point bending apparatus together with micro-Raman
facilities. Ultra-thin MoS2 samples are firstly exfoliated and then clamped onto a bendable material such as
polydimethylsiloxane (PDMS)13, SU8/polycarbonate14, polyethylene terephthalate (PET)15 and poly (methyl
methacrylate) (PMMA)16. Photoluminescence (PL) spectra are recorded at the moment when a mechanical strain
is exerted. Similar findings from the aforementioned literature have been reported: a red shift of PL emission
energy and decreased peak intensity under uniaxial tensile strain, conforming to the direct-to-indirect transition
of the optical band gap as predicated by theoretical studies. The observation can be qualitatively understood as
a result of reduced orbital overlap and hybridization due to weakened atomic bonds16. In complementary to the
above results, a blue shift of the PL peak and an increase of the emission intensity have been reported for biaxial
compressive strain exerted to tri-layer MoS2 through a piezoelectric substrate17. At the device level, back-gated
MoS2 transistors on a flexible substrate measured in the stretched state shows a shift of the transfer curve toward
lower back-gate voltages and an increase in electron current than the results measured in flat state18. g
gl
In this paper, we explore on the concept of “strain-gated” MoS2 MOSFET. Here, strain is exerted to MoS2
channel through the deposition of a silicon nitride stress capping layer that covers the entire transistor active area,
analogous to the industry-proven technique applied to the early generation of n-channel silicon transistors. To
enhance the field-effect mobility, uniaxial tensile strain along the transistor channel is favored to be generated in
order to reduce the band gap and electron effective mass. Current on/off ratio and other performance metrics are
measured as the transistors evolve from back-gated, to top-gated and finally, strain-gated structure. www.nature.com/scientificreports/ onto a Si/SiO2 substrate. The sample is divided into three regions: only region 2 is covered by 125 nm PECVD
silicon nitride; the intact regions 1 and 3 serve as control groups. This is to minimize potential non-uniformities
from different pristine bi-layer samples. f
p
y
p
Before nitride deposition, the bi-layer thickness and the homogeneity of the MoS2 sample are confirmed by PL
and Raman measurement. In all three regions, PL spectra show the two prominent emission peaks at 670 and
627 nm (Fig. 1c–e), corresponding to the two resonances known as A1 and B1 excitons21, and the Raman spectra
show a wavenumber difference of 22 cm−1 between the E2g
1 and A1g peak (Fig. 1f–h), a signature of bi-layer
MoS2
22. To show the similarities in peak intensity among the three regions, the spectra taken from the as-prepared
sample in Fig. 1 are re-plotted in overlapping format in Fig. S1 (Supplementary Information).it p
g
p
pp g
g
(
pp
y
)
In the post-deposition PL spectrum of region 2 (Fig. 1d), we find ~10 nm red shift of the A1 excitons (from
670 to ~680 nm), and about 40% decrease of the emission intensity. The decrease in peak emission energy is
~27 meV by using E = 1240/λ. The findings indicate a narrowed indirect bandgap possibly due to the tensile stress
from the nitride capping layer. Difference in thermal expansion coefficient between MoS2 and silicon nitride
could be another source of stress23. As the nitride layer was deposited at 120 °C, a tensile strain can be induced in
the MoS2 flake during the subsequent cooling of the sample to room temperature. For the Raman spectra, given
the fact that the referential peak of silicon remains at 520.7 cm−1 before and after nitride deposition, the
post-deposition spectrum of region 2 shows a red shift of the A1g peak (Δω ≈ 1.5 cm−1), while the shift of E2g
1
peak is negligible (Fig. 1g). We also observed this shift of A1g peak in other locations on the MoS2 sample covered
by the nitride slab, however no spatial correlations are concluded. The shift of the A1g peak also disappears once
the laser crosses either left or right boundary of the nitride slab. This change in Raman spectra could be due to an
extra strain in the out-of-plane direction13, but we are still trying to identify the reason behind. www.nature.com/scientificreports/ Regarding Region
1 and 3, no noticeable peak shift was observed either in PL or Raman characterization, the slightly dropped inten-
sity might originate from some resist reside adsorbed on the MoS2 surface at the lift-off step. The continuously
narrowed band gap of bi-layer MoS2 under tensile strain is calculated and shown in Fig. 2(a). The indirect band
gap of bi-layer MoS2 at 0% strain is 1.25 eV. It is clear that the band gap decreases as the tensile strain increases, the
tunability on average is ~100 meV per 1% tensile strain. Beyond 10%, the bi-layer MoS2 finally becomes close to
metallic. Based on the simulated result, the magnitude of the tensile strain induced by the nitride capping layer is
estimated to be much less than 1%. From the study of band structure in Fig. 2(b–d), the decrease in band gap is
mainly coming from the lowering of the conduction band at K point. The band structure keeps indirect through
all different tensile strain conditions. And the contribution of the band edge comes purely from Mo element’s
d-orbital.if Next, we design experiments to apply the nitride stress capping layer onto MoS2 field-effect transistors and
observe the strain’s influence on device performance. Figure 3 shows the three main stages for electrical charac-
terization, denoted as back-gate (BG), top-gate (TG) and strain-gate (SG). The key challenge for achieving the
final strain-gate configuration is fabricating MoS2 FETs with robust electrical contacts to endure multiple fab pro-
cessing and electrical measurement cycles. From our experience, the yield of working FET and the performance
repeatability are significantly improved with one-dimensional edge contacts24, in contrast to conventional surface
contacts which are affected by inherent surface defects found on natural MoS2 crystal25.fl f
y
y
Figure 4 shows the optical images captured at different stages of transistor fabrication. Firstly, MoS2 flakes were
directly exfoliated onto a Si/SiO2 substrate and a bi-layer region (faint purple color) was identified (Fig. 4a). The
thickness is confirmed by the 22 cm−1 difference between the E2g
1 and A1g modes and low wavenumber shear
mode E2g
2 (20 ~25 cm−1)26 (Fig. S2). After the first e-beam lithography step, the sites for source drain contacts were
patterned and etched by helium plasma (Fig. 4b). Instead of using SF6
24, helium plasma can prevent potential
oxidation of the exposed MoS2 atoms. The edge contacts are completed after metal evaporation (Sc/Ni) and lift-off
(Fig. 4c). www.nature.com/scientificreports/ At the completion of the electrical measurement on the back-gate transistors, the bi-layer region is cov-
ered by a top-gate dielectric comprised of an AlOx/HfO2 stack (Fig. 4d). The AlOx layer, which helps to increase
the nucleation sites for the atomic layer deposition of HfO2, was formed by e-beam evaporation of 2 nm alumi-
num seeds, followed by its overnight natural oxidation in air27. The MoS2 transistors were sent for electrical meas-
urement again after Ti/Au were deposited as the top-gate electrode (Fig. 4e). In the last lithography step, the entire
MoS2 flake, including both the multi-layer and device area, are sealed underneath the PECVD SiNx stress capping
layer (Fig. 4f). The recipe was the same as the one used in the Raman characterization. h
In total, three FETs are fabricated on this bi-layer MoS2, as labeled on Fig. 4e. To test whether all three are
functioning, the output and transfer characteristics were initially taken at the back-gate configuration (Fig. S3). The effective modulation of the drain current by VBG tells that all three edge-contacted FETs are working properly,
though some non-linearity and discrepancy is still observed in the output plots, which could be due to the dif-
ference in contact resistance. In order to make a fair comparison across the three stages of fabrication, from this
point on, the discussion is focused on the electrical performance of FET No.2. The full electrical characteristics of FET No. 2, comprising of results from back-gated, top-gated and
strain-gated transistor structure, are given in Fig. 5. Output plots are shown in the first row, in which VDS is swept
from −1 to 1 V. The inset of Fig. 5(a) enlarges the area close to the origin. From −200 to 200 mV, ID changes
almost linearly with VDS, indicating an Ohmic-like junction. From Fig. 5(a) to (c), qualitatively, the spreading
of the output curves along the vertical axis indicates continuously improved drain current and a more effective
current modulation from the top-gated voltages. Of note is that the top-gate voltages were set to 10 times smaller
than that for back-gate, for a much thinner top-gate dielectric and the enhanced over 60 times capacitance per
unit area. Results and Discussion First, we design sample structure to visualize the internal stress of the silicon nitride indirectly through the
Raman mode shift of MoS2 underneath. Silicon nitride (SiNx) deposited by plasma-enhanced chemical vapor
deposition (PECVD) are used in both Raman measurement and transistor characterization. As the ions do not
respond to the field at a single RF frequency of 13.56 MHz, a thin film deposited under such conditions typically
exhibits tensile stress19,20. As shown in Fig. 1(a) and (b), a bi-layer MoS2 sample was exfoliated and transferred Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 2 www.nature.com/scientificreports/ Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 www.nature.com/scientificreports/ As shown in the following equation, here we use 30 nm thick HfO2 with a theoretical relative permittiv-
ity of εr = 25, and 285 nm thick SiO2 with εr = 3.918: Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 3 www.nature.com/scientificreports/ Figure 2. Strained bi-layer MoS2 band structure calculation. (a) The continuously narrowed band gap
of bilayer MoS2 as a function of increasing lattice constant, the band structure with 1%, 5% and 10% tensile
strain are shown in (b,c and d). The blue and green dots in the figure represent Mo and S element occupation
respectively. Figure 2. Strained bi-layer MoS2 band structure calculation. (a) The continuously narrowed band gap
of bilayer MoS2 as a function of increasing lattice constant, the band structure with 1%, 5% and 10% tensile
strain are shown in (b,c and d). The blue and green dots in the figure represent Mo and S element occupatio
respectively. ε
ε
=
=
.
≈
C
C
d
d
nm
nm
/
25
30
3 9
285
61
(1)
HfO
SiO
HfO
HfO
SiO
SiO
2
2
2
2
2
2 (1) Gate transfer plots are in the second row of Fig. 5. We notice three important results across all three transfer
plots: 1) the drain current increases significantly at positive gate voltage, indicating n-type FET; 2) steep slopes of
the transfer curves when we switch from back-gate to top-gate; owing to the much improved top-gate capacitance
with HfO2, the change in slope is later manifested as an evident decrease in sub-threshold swing; 3) the continued
increase in drain current from top-gate to strain-gate, which proves that the deposition of the nitride stress liner
indeed helps to enhance the transistor’s electrical performance.hhfi p
p
The extracted carrier transport parameters are plotted in Fig. 6. The “on” and “off” currents are defined as the
maximum and the minimum currents in the measured gate voltage range. Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 www.nature.com/scientificreports/ The mobility values were obtained
firstly by curve fitting to each ID - VGS curve and then calculated by applying the following equation28: µ
=
⋅
⋅
⋅
g
L W
C
V
( /
)
(1/
)
(1/
)
(2)
FE
m
ox
DS µ
=
⋅
⋅
⋅
g
L W
C
V
( /
)
(1/
)
(1/
)
FE
m
ox
DS (2) where Cox = 1.2 × 10−8 F/cm2 is the capacitance per unit area of the 285 nm-thick SiO2 back- gate dielectric, and
Cox = 7.4 × 10−7 F/cm2 for 30 nm HfO2 top-gate dielectric. The aspect ratio of transistor No. 2 is W/L = 7.5/1.8 μm. Note that the maximum value of the transconductance
=
g
dI
dV
/
m
D
GS was used in the calculation. The data
plotted in Fig. 6 were all obtained at VDS = 1 V. From back- to top-gated FET, quantitatively, we notice a 5 times where Cox = 1.2 × 10−8 F/cm2 is the capacitance per unit area of the 285 nm-thick SiO2 back- gate dielectric, and
Cox = 7.4 × 10−7 F/cm2 for 30 nm HfO2 top-gate dielectric. The aspect ratio of transistor No. 2 is W/L = 7.5/1.8 μm. Note that the maximum value of the transconductance
=
g
dI
dV
/
m
D
GS was used in the calculation. The data
plotted in Fig. 6 were all obtained at VDS = 1 V. From back- to top-gated FET, quantitatively, we notice a 5 times Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 4 www.nature.com/scientificreports/ Figure 3. The three main stages for electrical characterization: (a) back-gate; (b) top-gate and (c) strain-gate. As
a tensile stressor inside the nitride film tends to shrink, the stressor on the source and drain pulls apart the ends
of the transistor channel and mainly produce a longitudinal tensile strain in the MOSFET channel2. The sites for
source drain contacts are engraved on the bi-layer MoS2. Figure 3. The three main stages for electrical characterization: (a) back-gate; (b) top-gate and (c) strain-gate. As
a tensile stressor inside the nitride film tends to shrink, the stressor on the source and drain pulls apart the ends
of the transistor channel and mainly produce a longitudinal tensile strain in the MOSFET channel2. The sites for
source drain contacts are engraved on the bi-layer MoS2. Figure 3. www.nature.com/scientificreports/ The three main stages for electrical characterization: (a) back-gate; (b) top-gate and (c) strain-gate. As
a tensile stressor inside the nitride film tends to shrink, the stressor on the source and drain pulls apart the ends
of the transistor channel and mainly produce a longitudinal tensile strain in the MOSFET channel2. The sites for
source drain contacts are engraved on the bi-layer MoS2. increase in on-current, ~98% decrease in off-current, significantly improved current on/off ratio from <100 to
~104, and a 43% increase in electron mobility. For the threshold voltage calculated using the linear extrapolation
method29, the value shrinks from −14 to −0.8 V; so does the sub-threshold swing, drops from 30 to 1.2 V. These
improvements are most likely originated from the higher gate capacitance of the more insulative HfO2 in the
top-gate structure. From top- to strain-gated FET, we find another 58% increase in electron mobility and 46%
increase in on-current magnitude, Vth decreases slightly to −0.7 V, and the sub-threshold swing remains relatively
small at 1.4 V. The consistancy in sub-threshold swing indicates that there is no change of the interface quality of
the dielectric layer. Distinct piezotronic response of the MoS2 was not observed, which is probably because of the
opposite orientation of alternating layers in bi-layer 2 H MoS2. Flakes with even number of layers are expected to
be centrosymmetric and non-piezoelectric30. As the nitride PECVD deposition temperature is lower than that for
contact annealing, we can conclude that the performance improvement is not due to a better contact, but a direct
result from the strain effect induced by the nitride capping layer. Though the magnitude of the mobility is still too
low for practical logic device, which is probably a result of the long span of time in multiple e-beam lithograpy
steps and repetitive electrical characterizations in between, the ideas presented in this paper can be undoubtedly
expanded to other TMDC semiconductor with high intrinsic mobilities. FET No. 3 exhibits similar carrier trans-
port enhancement as FET No. 2, the extracted electron mobilities at the corresponding BG – TG – SG are 0.11, increase in on-current, ~98% decrease in off-current, significantly improved current on/off ratio from <100 to
~104, and a 43% increase in electron mobility. www.nature.com/scientificreports/ For the threshold voltage calculated using the linear extrapolation
method29, the value shrinks from −14 to −0.8 V; so does the sub-threshold swing, drops from 30 to 1.2 V. These
improvements are most likely originated from the higher gate capacitance of the more insulative HfO2 in the
top-gate structure. From top- to strain-gated FET, we find another 58% increase in electron mobility and 46%
increase in on-current magnitude, Vth decreases slightly to −0.7 V, and the sub-threshold swing remains relatively
small at 1.4 V. The consistancy in sub-threshold swing indicates that there is no change of the interface quality of
the dielectric layer. Distinct piezotronic response of the MoS2 was not observed, which is probably because of the
opposite orientation of alternating layers in bi-layer 2 H MoS2. Flakes with even number of layers are expected to
be centrosymmetric and non-piezoelectric30. As the nitride PECVD deposition temperature is lower than that for
contact annealing, we can conclude that the performance improvement is not due to a better contact, but a direct
result from the strain effect induced by the nitride capping layer. Though the magnitude of the mobility is still too
low for practical logic device, which is probably a result of the long span of time in multiple e-beam lithograpy
steps and repetitive electrical characterizations in between, the ideas presented in this paper can be undoubtedly
expanded to other TMDC semiconductor with high intrinsic mobilities. FET No. 3 exhibits similar carrier trans-
port enhancement as FET No. 2, the extracted electron mobilities at the corresponding BG – TG – SG are 0.11, Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 5 www.nature.com/scientificreports/ www.nature.com/scientificreports/ Figure 4. The process flow for making strain-gated FETs (a) an optical image of a bi-layer MoS2 in faint purple
color on a Si/SiO2 substrate; (b) the material exposed in source drain sites have been etched by helium plasma;
(c) edge contact metal (Sc/Ni, 50/30 nm) evaporation and lift-off; (d) 30 nm HfO2 ALD deposition (with 2 nm
Al seed) and lift-off, for the bi-layer region only; (e) top-gate metal (Ti/Au, 10/60 nm) deposition, the FETs are
labeled No. 1, 2 and 3; (f) 125 nm SiNx PECVD deposition at 120 °C, capping both the multi-layer and the device
area. Figure 4. www.nature.com/scientificreports/ The process flow for making strain-gated FETs (a) an optical image of a bi-layer MoS2 in faint purple
color on a Si/SiO2 substrate; (b) the material exposed in source drain sites have been etched by helium plasma;
(c) edge contact metal (Sc/Ni, 50/30 nm) evaporation and lift-off; (d) 30 nm HfO2 ALD deposition (with 2 nm
Al seed) and lift-off, for the bi-layer region only; (e) top-gate metal (Ti/Au, 10/60 nm) deposition, the FETs are
labeled No. 1, 2 and 3; (f) 125 nm SiNx PECVD deposition at 120 °C, capping both the multi-layer and the device
area. 0.13 and 0.20 cm2/Vs, whereas no obvious performance improvement was observed in FET No. 1. It is possible
that PECVD gives rough granulated SiNx surface at lower deposition temperature31, leading to incoherent stress
experienced by the bi-layer MoS2 flake. 0.13 and 0.20 cm2/Vs, whereas no obvious performance improvement was observed in FET No. 1. It is possible
that PECVD gives rough granulated SiNx surface at lower deposition temperature31, leading to incoherent stress
experienced by the bi-layer MoS2 flake. In summary, we have characterized the strain induction in MoS2 through both spectroscopic study and elec-
trical measurement. We have also seen significant improvement in on-current density and mobility, when the
FET evolves from back-gated, to top-gated and finally to strain-gated configuration. We conclude that the pio-
neering approach of strain induction through a nitride stress liner has a benign effect on improving the carrier
transport property. It is also an industry-compatible and permanent solution for strain exertion without relying
on external substrate bending facilities. Further studies of the strain effect in “all 2D” transistors with perceived
greater flexibility would bring in deeper understanding of the tunibility of TMDCs’ electrical properties under
mechanical strain. l
In summary, we have characterized the strain induction in MoS2 through both spectroscopic study and elec-
trical measurement. We have also seen significant improvement in on-current density and mobility, when the
FET evolves from back-gated, to top-gated and finally to strain-gated configuration. We conclude that the pio-
neering approach of strain induction through a nitride stress liner has a benign effect on improving the carrier
transport property. It is also an industry-compatible and permanent solution for strain exertion without relying
on external substrate bending facilities. www.nature.com/scientificreports/ Further studies of the strain effect in “all 2D” transistors with perceived
greater flexibility would bring in deeper understanding of the tunibility of TMDCs’ electrical properties under
mechanical strain. Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 6 www.nature.com/scientificreports/ Methods
Figure 5. Electrical characterization of FET No. 2. Output plots (a to c) are in the first row, in which VDS is
swept from −1 to 1 V. The inset in (a) enlarges the area close to the origin. The names of the gate voltages tell
which process the plot corresponds to: BG – back-gate, TG – top-gate, SG – strain gate. Gate transfer plots
(d to f) are in the second row, with the linear axis on the left in black color and the log axis on the right in blue. The curves with filled markers correspond to a VDS bias of 1 V; those with empty markers have VDS of 100 mV. Figure 5. Electrical characterization of FET No. 2. Output plots (a to c) are in the first row, in which VDS is
swept from −1 to 1 V. The inset in (a) enlarges the area close to the origin. The names of the gate voltages tell
which process the plot corresponds to: BG – back-gate, TG – top-gate, SG – strain gate. Gate transfer plots
(d to f) are in the second row, with the linear axis on the left in black color and the log axis on the right in blue. The curves with filled markers correspond to a VDS bias of 1 V; those with empty markers have VDS of 100 mV. Methods Bi-layer MoS2 sample preparation. The bi-layer MoS2 sample for spectroscopic study was initially exfo-
liated onto a PDMS-based gel-film, and then transferred onto a pre-cleaned oxidized Si substrate through an all-
dry micro-manipulation procedure32. This additional exfoliation step on gel-film significantly improved the yield
of mono- and bi-layer MoS2 to almost 100%. The freshly cleaved ultra-thin regions usually come in area of a few
μm2, feasible for multiple transistor fabrication. The second bi-layer MoS2 sample used in strain-gated transistor
fabrication was prepared following the conventional Scotch-tape based mechanical exfoliation using bulk crystal. Raman and photoluminescence spectra were acquired under ambient conditions with a Horiba LabRAM HR
spectrometer equipped with a 523 nm laser supply and an 1800 lines/mm grating. A 100 × objective was used for
focusing the laser to an approximately 1 μm spot onto the sample. The laser power is < 1 mW to prevent sample
heating. Thin film thickness measurement was carried out under tapping mode from the AFM module of the
spectrometer. Strained bi-layer MoS2 band structure calculation. The band dispersions and band gap ener-
gies of bilayer MoS2 with and without strains were calculated using the Vienna ab initio simulation package
(VASP)33–35 in the projected-augmented-wave method36. The generalized gradient approximation (GGA) of the
Perdew-Burke-Ernzerhof form37–39 is used for the exchange correlation energy. The vdW interactions between
the two MoS2 layers are accounted by using the DFT-D2 method of Grimme40. The kinetic energy cutoff for our
calculation is set as 500 eV. The lattice constant of bilayer MoS2 without strain is about 3.179 Å. For all structural
relaxations, the convergence tolerance on the Hellmann-Feynman forces is less than 0.01 eV/Å. An 8 × 8 × 1
Monkhorst-Pack k-point mesh is used for 2D films. The vacuum layer added to the system is nearly 20 Å. The
other strained systems are all calculated under the same setting. Edge contacts and MoS2 transistors fabrication. A degenerately boron-doped (0.001~0.005 Ω•cm)
silicon substrate with 285 nm SiO2 capping layer, served as the global back gate and gate dielectric; silicon nitride
PECVD deposition: Plasma-therm Unaxis 790, deposition pressure 900 mTorr, power 25 W, RF frequency Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 7 www.nature.com/scientificreports/ Figure 6. A summary of the carrier transport properties of FET No. 2, encompassing the electrical
characterization made at the three stages of device fabrication: back-gate, top-gate and strain-gate. Figure 6. Methods A summary of the carrier transport properties of FET No. 2, encompassing the electrical
characterization made at the three stages of device fabrication: back-gate, top-gate and strain-gate. 13.56 MHz, 2% SiN4 200 sccm, NH3 4 sccm, N2 900 sccm, deposition time 10 mins at 120 °C, film thickness
125 nm; helium plasma for opening edge contacts: STS Reactive Ion Etcher Dielectric System, helium flow
rate 50 sccm, 75 W, 20 s; HfO2 ALD deposition: Cambridge Nanotech Savannah 100, 250 cycles at 120 °C, film
thickness 30 nm; Metal evaporation: Temescal BJD 1800 system, aluminum seed (2 nm, 0.1 Å/s), source drain
electrodes (Sc/Ni, 50/30 nm), back-gate electrode (Ti/Au, 10/100 nm), top-gate electrode (Ti/Au, 10/60 nm);
post-HfO2 deposition contacts annealing: RTP-600S system, 200 °C, Ar, 1 hour. The FETs were characterized in
a shielded probe station connected to an Agilent 4155 C semiconductor parameter analyzer. The entire measure-
ment was carried out at room temperature in air. 13.56 MHz, 2% SiN4 200 sccm, NH3 4 sccm, N2 900 sccm, deposition time 10 mins at 120 °C, film thickness
125 nm; helium plasma for opening edge contacts: STS Reactive Ion Etcher Dielectric System, helium flow
rate 50 sccm, 75 W, 20 s; HfO2 ALD deposition: Cambridge Nanotech Savannah 100, 250 cycles at 120 °C, film
thickness 30 nm; Metal evaporation: Temescal BJD 1800 system, aluminum seed (2 nm, 0.1 Å/s), source drain
electrodes (Sc/Ni, 50/30 nm), back-gate electrode (Ti/Au, 10/100 nm), top-gate electrode (Ti/Au, 10/60 nm);
post-HfO2 deposition contacts annealing: RTP-600S system, 200 °C, Ar, 1 hour. The FETs were characterized in
a shielded probe station connected to an Agilent 4155 C semiconductor parameter analyzer. The entire measure-
ment was carried out at room temperature in air. Referencesh 1. Thompson, S. E. et al. A 90-nm Logic Technology Featuring Strained-Silicon. IEEE Transactions on Electron Devices 51, 1790–1797
(2004). (
)
2. Xiong, W. W. In FinFETs and Other Multi-Gate Transistors 49–111 (Springer, 2008).h (
)
2. Xiong, W. W. In FinFETs and Other Multi-Gate Transistors 49–111 (Springer, 2008).h . Xiong, W. W. In FinFETs and Other Multi-Gate Transistors 49–11h g
p
g
3. Thompson, S. E. et al. A 90 nm Logic Technology Featuring 50 nm Strained Silicon Channel Transistors, 7 layers of Cu Interconn 3. Thompson, S. E. et al. A 90 nm Logic Technology Featuring 50 nm Strained Silic
Low k ILD, and 1 μm2 SRAM Cell. IEDM Technical Digest. 61–64 (IEEE, 2002) h
p
g
gy
g
Low k ILD, and 1 μm2 SRAM Cell. IEDM Technical Digest. 61–64 (IEEE, 2002). g
ng, M. K. et al. Silicon Device Scaling to the Sub-10-nm Regime. Sf g
4. Ieong, M. K. et al. Silicon Device Scaling to the Sub-10-nm Regime. Science 306, 2057–2060 (2004).f g
g
g
(
)
5. Ito, S. et al. Mechanical stress effect of etch-stop nitride and its impact on deep submicron transistor design. In Electron Device
Meeting, 2000. IEDM’00. Technical Digest. International 247–250 (IEEE, 2000). g
g
g
5. Ito, S. et al. Mechanical stress effect of etch-stop nitride and its impact on deep submicro
Meeting, 2000. IEDM’00. Technical Digest. International 247–250 (IEEE, 2000). g
g
6. Ge, C.-H. et al. Process-strained Si (PSS) CMOS technology featuring 3D strain engineering. In Electron Devices Meeting, 2003
IEDM’03 Technical Digest. IEEE International 3–7 (IEEE, 2003). g
(
)
7. Ghani, T. et al. A 90 nm high volume manufacturing logic technology featuring novel 45 nm gate length strained silicon CMOS
transistors. In Electron Devices Meeting, 2003. IEDM’03 Technical Digest. IEEE International 11–6 (IEEE, 2003). g
g
8. Mistry, K. et al. Delaying forever: Uniaxial strained silicon transistors in a 90nm CMOS technology. in Symposium on VLS
Technology 50–51 (2004). g
g
8. Mistry, K. et al. Delaying forever: Uniaxial strained silicon transistors in a 90nm CMO
Technology 50–51 (2004). gy
(
)
9. Van der Zande, A. & Hone, J. Inspired by Strain. Nature Photonics 6, 804–806 (2012). gy
Van der Zande, A. & Hone, J. Inspired by Strain. Nature Photonics 6 nde, A. & Hone, J. Inspired by Strain. Nature Photonics 6, 804–806 ( p
y
10. Bertolazzi, S., Brivio, J. Referencesh & Hafner, J. Ab initio molecular dynamics for liquid metals. Physical Review B 47, 558 (1993).fi Kresse, G. & Hafner, J. Ab initio molecular dynamics for liquid metfi 34. Kresse, G. & Hafner, J. Ab initio molecular dynamics for liquid metals. Physical Review B 47, 558 (1993).fi y
q
y
35. Kresse, G. & Furthmüller, J. Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave
set Computational Materials Science 6 15 (1996) 35. Kresse, G. & Furthmüller, J. Efficiency of ab-initio total energy calculations for metals and semiconductors u
set. Computational Materials Science 6, 15 (1996). p
36. Blöchl, P. E. Projector augmented-wave method. Physical Review B 50, 17953 (1994). Blöchl, P. E. Projector augmented-wave method. Physical Review B 36. Blöchl, P. E. Projector augmented-wave method. Physical Review B 50, 17953 (1994). 36. Blöchl, P. E. Projector augmented-wave method. Phys 37. Perdew, J. P. et al. Atoms, molecules, solids, and surfaces: Applications of the generalized gradient approximation for exchange
correlation. Physical Review B 46, 6671 (1992). y
8. Wang, Y. & Perdew, J. P. Correlation hole of the spin-polarized electron gas, with exact small-wave-vector and high-density scaling
Physical Review B 44, 13298 (1991).t 38. Wang, Y. & Perdew, J. P. Correlation hole of the spin-polarized electron gas, with exact small-wave-vector and high-density scaling. Physical Review B 44, 13298 (1991).t y
,
(
)
9. Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Physical Review B 59, 1758
(1999). y
39. Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Physical Review B 59, 1758
(1999). 39. Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Physical Review B 59, 1758
(1999). 40 Harl J Schimka L & Kresse G Assessing the quality of the random phase approximation for lattice constants and atomization (
)
0. Harl, J., Schimka, L. & Kresse, G. Assessing the quality of the random phase approximation for lattice constants and atomization
energies of solids. Physical Review B 81, 115126 (2010). Acknowledgements Financial support for this work was provided by two STARnet centers, C-SPIN (Center for Spintronic Materials,
Interfaces and Novel Architectures) and FAME (Center for Function Accelerated Nanomaterial Engineering),
through the Semiconductor Research Corporation sponsored by the MARCO (Microelectronics Advanced
Research Corporation) and the DARPA (Defense Advanced Research Projects Agency). This work used the
Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by the NSF (National
Science Foundation) under grant no: ACI-1053575. Author Contributions Y.C., C.S.O., M.O. and R.L. designed the experiments and wrote the manuscript. Y.C. fabricated the device
samples, performed the electrical measurements and analyzed the results. S.S. and R.L. worked on the calculation
of strained band structures and conducted the corresponding analysis. D.Y. conducted silicon nitride deposition
for strain control and provided valuable discussions. C.S.O. managed the research team. All authors reviewed the
manuscript. Referencesh & Kis, A. Stretching and Breaking of Ultrathin MoS2. ACS Nano 5, 9703–9709 (2011).hf 10. Bertolazzi, S., Brivio, J. & Kis, A. Stretching and Breaking of Ultrathin MoS2. ACS Na g
g
11. Yun, W. S., Han, S. W., Hong, S. C., Kim, I. G. & Lee, J. D. Thickness and strain effects on electronic structures of transition metal
dichalcogenides: 2H-MX2 semiconductors ( M = Mo, W; X = S, Se, Te). Physical Review B 85, 033305 (2012).fif g
y
12. Zeng, L., Xin, Z., Chang, P. & Liu, X. Strain effects on monolayer MoS2 field effect transistors. Japanese Journal of Applied Physi
04DC17 (2015).fi 13. Yang, L. et al. Lattice strain effects on the optical properties of MoS2 nanosheets. Scientific Reports 4 (2014). fi
4. Conley, H. J. et al. Bandgap Engineering of Strained Monolayer and Bilayer MoS2. Nano Letters 13, 3626–3630 (2013). 15. Zhu, C. R. et al. Strain tuning of optical emission energy and polarization in monolayer and bilayer MoS2. Physical Review B 88,
121301 (2013). 6. He, K., Poole, C., Mak, K. F. & Shan, J. Experimental Demonstration of Continuous Electronic Structure Tuning via Strain in
Atomically Thin MoS2. Nano Letters 13, 2931–2936 (2013). Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 8 www.nature.com/scientificreports/ 7. Hui, Y. Y. et al. Exceptional Tunability of Band Energy in a Compressively Strained Trilayer MoS2 Sheet. ACS Nano 7, 7126–7131
(2013).f 17. Hui, Y. Y. et al. Exceptional Tunability of Band Energy in a Compressively Strained Trilayer MoS2 Sheet. ACS Nano 7, 7126–7131
(2013). 18 T i M Y t l Fl
ibl M S Fi ld Eff
t T
i t
f
G t
T
bl Pi
i ti
St
i
S
ACS Appli d M t i l & (2013). 18. Tsai, M.-Y. et al. Flexible MoS2 Field-Effect Transistors for Gate-Tunable Piezoresistive Strain Sensors. ACS Applied Materials & 8. Tsai, M.-Y. et al. Flexible MoS2 Field-Effect Transistors for Gate-Tunable Piezoresistive Strain Sensors. ACS Applied Materials &
Interfaces 7, 12850–12855 (2015). f
(
)
9. Gatzen, H. H., Saile, V. & Leuthold, J. In Micro and Nano Fabrication: Tool and Processes, 65–203 (Springer Berlin Heidelberg, 2015) J
( p
g
g
)
20. Mackenzie, K. D., Johnson, D. J., DeVre, M. W., Westerman, R. J. & Reelfs, B. H. Stress control of Si-based PECVD dielectrics. In
Electrochemical Society Meeting 148–159, Pennington, NJ (2005). Referencesh 21 S l
di
i A
l E
i
Ph
l
i
i M
l
M S N
L
10 1271 1275 (2010) y
g
g
21. Splendiani, A. et al. Emerging Photoluminescence in Monolayer MoS2. Nano Letters 10, 1271–1275 (2010). 22. Lee, C., Yan, H., Brus, L. E., Heinz, T. F., Hone, J. & Ryu, S. Anomalous Lattice Vibrations of Single and Few-Layer MoS2. ACS
4, 2695–2700 (2010). 3. Plechinger, G. et al. Low-temperature photoluminescence of oxide-covered single-layer MoS2. Physica Status Solidi (RRL) - Rapid
Research Letters 6, 126–128 (2012).i 4. Chai, Y. et al. Making one-dimensional electrical contacts to molybdenum disulfide-based heterostructures through plasma etching
Physica Status Solidi A. (2016). 25. McDonnell, S., Addou, R., Buie, C., Wallace, R. M. & Hinkle, C. L. Defect-Dominated Doping and Contact Resistance in MoS2. ACS
Nano 8, 2880–2888 (2014).i 6. Zeng, H. et al. Low-frequency Raman modes and electronic excitations in atomically thin MoS 2 films. Physical Review B 86, 241301
(2012). (
)
7. Zhu, W. et al. Electronic transport and device prospects of monolayer molybdenum disulphide grown by chemical vapou
deposition. Nature Communications 5 (2014). p
(
)
28. Sze, S. M. & Ng, K. K. In Physics of Semiconductor Devices (3rd ed) chap. 6 (Wiley-Interscience, 2007). 28. Sze, S. M. & Ng, K. K. In Physics of Semiconductor Devices (3rd g
y
f
y
29. Schroder, D. K. In Semiconductor Material and Device Characterization, p.223. (John Wiley & Sons, Inc., 2006). 30. Wu, W. et al. Piezoelectricity of single-atomic-layer MoS2 for energy conversion and piezotronics. Nature 514, 470–474 (2014) y
g
y
gy
p
31. Semendy, F. et al. Characterization of Multi Temperature and Multi RF Chuck Power Grown Silicon Nitride Films by PECVD and
ICP Vapor Deposition Army Resarch Laboratory ARL TR 5105 (2010) 31. Semendy, F. et al. Characterization of Multi Temperature and Multi RF Chuck Power Grown Silicon Nitride Films by PECVD and
ICP Vapor Deposition. Army Resarch Laboratory, ARL-TR-5105 (2010). 31. Semendy, F. et al. Characterization of Multi Temperature and Multi RF Chuck
ICP Vapor Deposition. Army Resarch Laboratory, ARL-TR-5105 (2010). y
y
2. Castellanos-Gomez, A. et al. Deterministic transfer of two-dimensional materials by all-dry viscoelastic stamping. 2D Materials 1
011002 (2014).fi 33. Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phy
Review B 54, 11169 (1996). (
)
34. Kresse, G. Additional Information upplementary information accompanies this paper at http://www.nature.com/srepi Supplementary information accompanies this paper at http://www.nature.com/srepi Competing financial interests: The authors declare no competing financial interests. Competing financial interests: The authors declare no competing financial interests. How to cite this article: Chai, Y. et al. Strain Gated Bilayer Molybdenum Disulfide Field Effect Transistor with
dge Contacts. Sci. Rep. 7, 41593; doi: 10.1038/srep41593 (2017). Publisher's note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and
institutional affiliations. This work is licensed under a Creative Commons Attribution 4.0 International License. The images
or other third party material in this article are included in the article’s Creative Commons license,
unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license,
users will need to obtain permission from the license holder to reproduce the material. To view a copy of this
license, visit http://creativecommons.org/licenses/by/4.0/ © The Author(s) 2017 Scientific Reports | 7:41593 | DOI: 10.1038/srep41593 9
|
https://openalex.org/W4313948729
|
https://dr.ntu.edu.sg/bitstream/10356/170371/2/PDF.pdf
|
English
| null |
Medical Student Experiences of Engaging in a Psychological Flexibility Skill Training App for Burnout and Well-being: Pilot Feasibility Study
|
JMIR formative research
| 2,023
|
cc-by
| 18,649
|
Medical student experiences of engaging in a
psychological flexibility skill training app for
burnout and well‑being: pilot feasibility study Ditton, Elizabeth; Knott, Brendon; Hodyl, Nicolette; Horton, Graeme; Walker, Frederick
Rohan; Nilsson, Michael Ditton, Elizabeth; Knott, Brendon; Hodyl, Nicolette; Horton, Graeme; Walker, Frederick
Rohan; Nilsson, Michael 2023 Ditton, E., Knott, B., Hodyl, N., Horton, G., Walker, F. R. & Nilsson, M. (2023). Medical
student experiences of engaging in a psychological flexibility skill training app for burnout
and well‑being: pilot feasibility study. JMIR Formative Research, 7, e43263‑. https://dx.doi.org/10.2196/43263 Ditton, E., Knott, B., Hodyl, N., Horton, G., Walker, F. R. & Nilsson, M. (2023). Medical
student experiences of engaging in a psychological flexibility skill training app for burnout
and well‑being: pilot feasibility study. JMIR Formative Research, 7, e43263‑. https://dx.doi.org/10.2196/43263 https://hdl.handle.net/10356/170371
https://doi.org/10.2196/43263 https://hdl.handle.net/10356/170371 https://doi.org/10.2196/43263 Corresponding Author: Corresponding Author:
Elizabeth Ditton, BA (Psych) Hons, MA Psych (Clin)
Centre for Rehab Innovations
University of Newcastle
University Drive
Callaghan, 2300
Australia
Phone: 61 2 404 20738
Email: elizabeth.ditton@uon.edu.au Original Paper Original Paper https://formative.jmir.org/2023/1/e43263 https://doi.org/10.2196/43263 © Elizabeth Ditton, Brendon Knott, Nicolette Hodyl, Graeme Horton, Frederick Rohan
Walker, Michael Nilsson. Originally published in JMIR Formative Research
(https://formative.jmir.org), 10.01.2023. This is an open‑access article distributed under the
terms of the Creative Commons Attribution License
(https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work, first published in
JMIR Formative Research, is properly cited. The complete bibliographic information, a link
to the original publication on https://formative.jmir.org, as well as this copyright and
license information must be included. Downloaded on 24 Oct 2024 12:09:45 SGT JMIR FORMATIVE RESEARCH Ditton et al Medical Student Experiences of Engaging in a Psychological
Flexibility Skill Training App for Burnout and Well-being: Pilot
Feasibility Study Elizabeth Ditton1,2,3, BA (Psych) Hons, MA Psych (Clin); Brendon Knott4, BSc (Psych) Hons, MA Psych (Clin);
Nicolette Hodyl1,2,5, BSc Hons, GradCert Biostats, PhD; Graeme Horton3, BS, MB, MEnvStud, PhD; Frederick Rohan
Walker1,2,3*, BA (Psych) Hons, PhD; Michael Nilsson1,2,3,6*, MD, PhD 1Centre for Rehab Innovations, University of Newcastle, Callaghan, Australia
2Hunter Medical Research Institute, New Lambton Heights, Australia
3College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, Australia
4Contextual Interventions, Newcastle, Australia
5New South Wales Regional Health Partners, Newcastle, Australia
6Lee Kong Chian School of Medicine, Nanyang Technological University, Singaport, Singapore
*these authors contributed equally 1Centre for Rehab Innovations, University of Newcastle, Callaghan, Australia
2Hunter Medical Research Institute, New Lambton Heights, Australia
3College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, Australia
4Contextual Interventions, Newcastle, Australia
5New South Wales Regional Health Partners, Newcastle, Australia
6Lee Kong Chian School of Medicine, Nanyang Technological University, Singaport, Singapore
*these authors contributed equally KEYWORDS medical students; burnout prevention; app; feasibility; intervention engagement; psychological flexibility; acceptance and
commitment therapy; mobile phone medical students; burnout prevention; app; feasibility; intervention engagement; psychological flexibility; acceptance and
commitment therapy; mobile phone of such interventions using stand-alone smartphone apps [1,3]. Although the preliminary feasibility of app-delivered
interventions (eg, mindfulness) has been demonstrated among
small samples of medical residents [22,23], there are no studies
evaluating feasibility among medical students. Medical students
use smartphones frequently and are accustomed to engaging
with technology [1,24,25] and, thus, app-delivered interventions
have the potential to be accessible [1,26] and scalable [12]. Apps could facilitate medical students’access to psychological
skill training anytime and anywhere [27], which is particularly
important when the availability of psychological health care
personnel is limited or face-to-face delivery is not practical. App-delivered interventions may also offset known barriers to
medical student engagement in psychological interventions by
maintaining anonymity and privacy for students concerned
about mental health stigma [1,6] and delivering brief
intervention components that minimize participation-related
time pressures [28]. Finally, app-delivered interventions provide
a potential solution to the problem of heterogeneity and variation
in individual responses to psychological interventions [29] by
facilitating the tailoring of training to individual medical student
needs (ie, individualization) [27]. Individualized psychological
apps
have
demonstrated
greater
effectiveness
than
nonindividualized apps with respect to well-being outcomes
among heterogeneous university student samples [27]. Medical Student Stress and Psychological Health The stress of medical training can have adverse effects on
students’ psychological health [1-3]. Worldwide, medical
students are at an elevated risk of psychological ill health
compared with the general population [1], demonstrating high
prevalence of burnout (44.2% [4]), depression (27.2% [2]), and
suicidal ideation (11.1% [2]). Burnout risk increases as training
progresses [5] and can persist throughout a physician’s
professional life [6]. The detrimental consequences of burnout
and psychological ill health among medical students and
physicians are well documented and include poor physical health
[7], diminished life satisfaction [6], and disruption to health
care service delivery (eg, impaired performance [8] and reduced
empathy [5] and work engagement [9]). Adaptive Psychological Skill Training Medical educators report increasing concern regarding the
psychological health of students [10] and recognize the need
for early intervention strategies that can prevent burnout rather
than treat it after it has already emerged [10-12]. In addition to
organizational approaches that mitigate modifiable external
stressors (eg, improving learning environments and addressing
student mistreatment [13]), there is support for initiatives that
build individual psychological and behavioral resources for
coping with unmodifiable stressors encountered during medical
education and practice [10,12,14,15] (eg, academic pressures
and exposure to illness and death [5,6]). This intervention
strategy has the potential to buffer medical students against
burnout and psychological ill health by facilitating adaptive
responses to stressful experiences [6,15,16]. Beyond simply
preventing psychological ill health, adaptive psychological skill
training can improve well-being [17,18]. Well-being is a state
of personal thriving and vitality that is an essential component
of complete psychological health [19,20] and a key outcome of
interest to medical educators [10]. There is support for the
acceptability
of
adaptive
psychological
skill-building
interventions among medical students [3] and physicians
experiencing burnout, with the latter having rated such training
as being as important as learning clinical skills [21]. Despite the potential advantages of app-delivered interventions
for medical student psychological health, there are several
challenges that could affect the feasibility of this strategy. Maintaining individual participation in psychological health
apps is a known problem generally, with real-world user
engagement diminishing substantially within 2 to 4 weeks of
sign-up [30]. Engagement can be affected by a range of usability
and acceptability factors, including the quality and functionality
of the interface [1,31], training content relevance [26], the
context in which the intervention is experienced [31], time
burden [22], and user experiences [1] (eg, affective responses,
perceived effectiveness, and self-efficacy [31]). Given the infancy of this emerging field and intervention
delivery mode, feasibility assessment is an important precursor
to successful implementation in larger efficacy trials [32]. There
is a need for studies that formally evaluate medical students’
subjective
experiences
of
engaging
in
app-delivered
psychological interventions as well as their perceptions of
interface usability [1,33]. The absence of this information from
the literature has been noted as a hindrance to progressing
digitally delivered psychological skill interventions beyond the https://formative.jmir.org/2023/1/e43263 JMIR FORMATIVE RESEARCH Ditton et al Conclusions: This study reports user experience data that have been largely absent from the literature on digital psychological
interventions for medical students. Our findings demonstrate the preliminary feasibility of an app-delivered ACTraining intervention
for medical student well-being and burnout and support the value of future assessment of the efficacy of this approach with larger
samples. We consider subjective feedback from medical students in relation to observed engagement and propose how this
information might be used to inform the development of this app and future research in this nascent field. (JMIR Form Res 2023;7:e43263) doi: 10.2196/43263 JMIR Form Res 2023 | vol. 7 | e43263 | p. 2
(page number not for citation purposes) Abstract Background: Medical students are at higher risk of burnout than the general population. Interventions that facilitate adaptive
coping behaviors (eg, Psychological Flexibility) in the context of inherent stressors associated with medical training could mitigate
burnout risk and improve well-being. Delivering these interventions using smartphone apps offers advantages such as accessibility,
scalability, mitigation of time and stigma barriers, and facilitation of individual tailoring (individualization). There is a need for
feasibility trials with medical students in this emerging field. Formal evaluations of user experiences of app-based psychological
skill training are required to identify barriers to and facilitators of engagement and optimize intervention development before
implementation in efficacy trials and real-world settings. Objective: This study aimed to assess the feasibility of delivering an individualized Psychological Flexibility skill training
intervention (Acceptance and Commitment Training [ACTraining]) to medical students using an app-based delivery format. We
further aimed to explore how formal evaluation of user experiences might inform and guide the development of this app before
implementation in an efficacy trial and future research involving app-delivered psychological skill training for medical students. Methods: This single-arm study was an early-phase feasibility trial of a stand-alone ACTraining app conducted with a sample
of Australian medical students (n=11). We collected app usability and user experience data across a broad range of domains (eg,
perceived helpfulness and relevance, learning experiences, and self-efficacy) using self-report questionnaires (quantitative and
qualitative) and behavioral engagement outcomes. Results:
Behavioral engagement data demonstrated that the app delivered the assessment procedures and individualized
ACTraining intervention to medical students as intended. The subjective feedback provided by students who actively engaged
with the app was generally positive across several indicators, including usability, perceived relevance and helpfulness, accessibility,
maintenance of privacy, and opportunity for self-reflection. Disengagement from the app was an identified challenge throughout
the trial. Participant feedback identified several factors that may have affected engagement, such as time, expectations regarding
app interface functioning, and individual differences in confidence and self-efficacy when implementing skills. JMIR Form Res 2023 | vol. 7 | e43263 | p. 1
(page number not for citation purposes) JMIR Form Res 2023 | vol. 7 | e43263 | p. 1
(page number not for citation purposes) XSL•FO
RenderX JMIR FORMATIVE RESEARCH Intervention Model: Psychological Flexibility There are no standardized psychological skill training
interventions available for medical student burnout and
psychological
well-being
[3]. However,
Psychological
Flexibility is an adaptive behavioral skill set that has been shown
to protect against adverse mental health outcomes in stressful
situations [18,36-41] and is emerging as a promising intervention
target [17,18,37,42]. The model encompasses 6 modifiable
behavioral flexibility (and corresponding inflexibility) processes:
present-moment awareness (nonawareness), experiential
acceptance
(avoidance),
cognitive
defusion
(fusion),
self-as-context (self-as-content), contact with values (noncontact
with values), and committed action toward values (inaction)
[43]. When exposed to stressful situations, individuals who are
high in Psychological Inflexibility tend to respond in ways that
are rigidly driven by their internal experiences (eg, fusion with
unhelpful thoughts, rules, or self-stories, and avoidance of
emotional discomfort). This can increase their risk of adverse
psychological outcomes by restricting coping repertoires,
disrupting engagement in personally meaningful behaviors, and
exacerbating distress [36,44,45]. Conversely, as psychologically
flexible individuals are more able to adopt an open and
nonevaluative stance toward internal experiences, they are less
likely to interpret emotionally uncomfortable stressors as
threatening to their well-being [36]. By focusing less on
avoiding or reducing discomfort and more on connecting with
and accepting their direct experiences, psychologically flexible
individuals are able to recognize a broader range of situational
opportunities available to them when responding to stressful
conditions [40,46]. This facilitates purposeful action toward
personally held values and related goals [43]. Early evidence
supports the potential relevance of Psychological Flexibility
skills to medical students, who are less likely to experience
burnout when they adopt experiential acceptance [6,47] and
engage in values-driven actions [48]. Conversely, low
Psychological Flexibility among medical students is associated
with an elevated risk of burnout [49], reduced life satisfaction,
and greater personal distress when seeing others in harm [50]. At the content level, ACTraining offers potential feasibility
benefits with respect to its acceptability and relevance to medical
students. ACTraining adopts a normalizing stance toward
uncomfortable internal responses to stressors (ie, thoughts,
emotions, and physical sensations) [43,56], providing
opportunities to learn adaptive behavioral skills in a
nonstigmatizing way. Furthermore, as ACTraining encourages
action driven by awareness of an individual’s unique
experiences, values, and goals [43], students can learn to apply
the skills in ways that are personally relevant. However, aspects
of ACTraining (eg, self-reflection and bringing attention to
uncomfortable thoughts and emotions) may be challenging when
experienced in a self-directed app-based context without guided
support [26]. App-Delivered Interventions The increased interest in medical student psychological health
has resulted in a growing number of studies evaluating
individual skill-building interventions [3]. A notable gap in this
emerging field is the absence of studies evaluating the delivery XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al and improved well-being and diminished psychological distress
among female medical students [52]. ACTraining is well suited
to an app-based format as it teaches Psychological Flexibility
skills using metaphors and experiential activities that can be
delivered as brief and practical training components [27]. By
facilitating opportunities to practice during the course of medical
students’
everyday
lives,
app-delivered
ACTraining
interventions could strengthen and generalize Psychological
Flexibility skills [27]. Furthermore, as ACTraining components
have functional links with their corresponding Psychological
Flexibility processes [43,45,53], interventions can be
individualized within an app by identifying which skill a student
requires the most assistance with in a particular moment and
aligning the delivery of targeted components with these needs
[27]. This is important given the heterogeneity of Psychological
Flexibility skill profiles between individuals and the fact that
the 6 processes can vary independently of one another
[44,54,55], suggesting that medical students are likely to require
training in different skills at different times and in different
situations [44]. prototype phase to effective, fully developed products that could
be successfully implemented in medical education settings [1]. The collection of these data can provide information about how
psychological skill training apps are experienced in real-world
contexts among medical student end users [32,34], unexpected
methodological issues and barriers [32], and factors that may
affect engagement [34,35]. prototype phase to effective, fully developed products that could
be successfully implemented in medical education settings [1]. The collection of these data can provide information about how
psychological skill training apps are experienced in real-world
contexts among medical student end users [32,34], unexpected
methodological issues and barriers [32], and factors that may
affect engagement [34,35]. Intervention Model: Psychological Flexibility Evaluating medical students’
subjective
experiences of engaging with ACTraining content is an
important aspect of feasibility assessment, particularly given
the potential impact on app engagement [26]. To our knowledge,
no feasibility data of this nature have been reported previously. This Study This study is a small-scale feasibility assessment of an adaptive
psychological skill training app for medical student burnout
prevention and well-being using an evidence-informed
behavioral model (Psychological Flexibility). https://formative.jmir.org/2023/1/e43263 JMIR Form Res 2023 | vol. 7 | e43263 | p. 3
(page number not for citation purposes) Study Aims and Objectives We developed an individualized Psychological Flexibility skill
training app (using an ACTraining intervention approach) for
medical student burnout and well-being. The aims of this study
were to assess the feasibility of delivering an ACTraining
intervention to medical students using an app-based delivery
format, and explore how formal evaluation of subjective user
experiences might inform and guide the development of this
app before implementation in a planned efficacy trial as well
as future research regarding psychological skill training apps
for medical students. This study was an early implementation
trial conducted with a small sample of Australian medical
students who were interested in engaging in an app-based
burnout prevention and well-being intervention. We collected
behavioral engagement data and detailed student feedback
regarding the ACTraining intervention content, usability of the
app interface, and experiences of engaging with the intervention
across a range of acceptability domains (eg, affective responses,
perceived learning, self-efficacy, and engagement barriers and
facilitators). Acceptance and Commitment Training Study Design All aspects of the study were implemented on the web. A digital
invitation was sent from a Joint Medical Program administrative
account to the students’ university email accounts, and a
follow-up invitation was sent a few days before the final
enrollment date. Students also received a verbal invitation at
the end of a web-based class delivered by a member of the
research team. Participation in the study was voluntary. Students
were given a URL and QR code that allowed them to access
the enrollment website (hosted on a secure web-based survey
and database platform, REDCap [Research Electronic Data
Capture; Vanderbilt University]) that provided information
about the study and allowed students to enroll using an e-consent
process. After completing a brief demographic questionnaire,
consented students were allocated a unique (4-digit) participant
ID and provided links to download the app via the App Store
(Apple) and Play Store (Android). After downloading the app,
students created an account. All further assessment, data
collection, and intervention procedures were conducted via the
app, which students accessed independently during the study
period. Self-report outcomes were measured at 3 time points:
baseline (t0), following stage 1 of the intervention (t1), and
following stage 2 of the intervention (t2). Owing to the time
commitment involved in the study, an Aus $30 (US $20.43)
gift voucher was offered to participants who completed the
intervention and self-report outcome measures. Figure 1 shows
the participant flow diagram. This study was a single-arm feasibility trial of a 2-stage
individualized ACTraining app. Acceptance and Commitment Training Psychological Flexibility skills can be developed and
strengthened using Acceptance and Commitment Training
(ACTraining) [43]. ACTraining interventions implemented in
medical education settings have demonstrated beneficial impacts
such as reduced burnout among distressed medical students [51] XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al all members of the sampling frame met this criterion. There
were no ineligibility criteria. JMIR Form Res 2023 | vol. 7 | e43263 | p. 4
(page number not for citation purposes) Participants, Recruitment, and Study Setting We aimed to recruit approximately 10 to 15 participants,
consistent with sample size recommendations for feasibility
studies [35]. As the app had not been trialed previously, we
limited the number of participants to allow for a smaller-scale,
detailed end-user evaluation before broader implementation in
a planned larger efficacy trial [57]. Recruitment occurred over
a 3-week period in June 2021. The sampling frame was all students enrolled in year 3 of the
Joint Medical Program at the University of Newcastle and
University of New England (Australia) during semester 1 of
2021 (N=170). Year 3 students were selected for pragmatic
reasons (eg, timing of the study in relation to academic demands
and the impact of the COVID-19 pandemic), as recommended
by the University of Newcastle head of medical student
well-being (GH). Students were eligible for inclusion if they
had regular access to a reliable internet connection and an
electronic device compatible with app use (smartphone or
tablet). Although the ability to understand English was a
requirement for using the app, this was not stated explicitly as https://formative.jmir.org/2023/1/e43263 https://formative.jmir.org/2023/1/e43263 XSL•FO
RenderX XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al Figure 1. Participant flow diagram. Figure 1. Participant flow diagram. peer-reviewed journal publications); (3) nonidentifiable data
may be used for future ethically approved research; and (4) if
students elected to withdraw from the study, data provided up
to the point of withdrawal would be retained and included in
the study in a deidentified and anonymized form. Ethical Considerations Ethics approval for this study was granted by the University of
Newcastle Human Research Ethics Committee on January 21,
2021 (approval ID: H-2020-0311) and ratified by the University
of New England Human Research Ethics Committee on
February 11, 2021. To ensure the privacy and anonymity of
participant data, 2 password-protected databases were used to
store personal and demographic information (in an identifiable
Participant Information Database) separately from the outcome
data (stored in an anonymous Study Database). Outcome data
were deidentified, with participant ID used as a linkage key. Only the lead author had access to the Participant Information
Database. Members of the research team did not have access to
identifying participant information. To protect privacy while
using the app, students input their unique participant ID as their
username when creating and accessing their accounts. JMIR Form Res 2023 | vol. 7 | e43263 | p. 5
(page number not for citation purposes) https://formative.jmir.org/2023/1/e43263 Stage 2: Individualized Skill Training Teach students to identify their own personally held values and
notice how connection or disconnection with these values can
contribute to well-being or burnout experiences, respectively
Values
Students select a personally held val
to them in that moment and commit
achievable action toward that value
Teach students to choose effective and purposeful behaviors that
align with personally held values even when internal discomfort
is present; use direct experiences to recognize the difference be-
tween well-being–oriented action and inflexible persistence that
could increase burnout risk
Committed ac-
tion Table 1. Aims and example activities for each Psychological Flexibility skill set. Example activity Guided mindfulness activity in which students practice attending
to specific aspects of their present-moment experience (eg,
sounds, physical sensations, thoughts, emotions, and breathing) Students practice responding flexibly to a thought by choosing
an action that contradicts a thought they are having (eg, they are
asked to think “I can’t lift my arm” and to also lift their arm). Students identify a “self-story” that causes distress or limits their
response options in certain situations and practice choosing ac-
tions that expand their behavioral repertoires outside of these
stories. Students identify a “self-story” that causes distress or limits their
response options in certain situations and practice choosing ac-
tions that expand their behavioral repertoires outside of these
stories. Teach students to recognize that their thoughts and emotions do
not define their identity but are transient aspects of their experi-
ence, which they can observe from a more stable and constant
sense of “self” Teach students to identify unhelpful avoidance behaviors and
practice open, flexible, and adaptive ways of responding to inter-
nal discomfort Students practice observing an uncomfortable sensation (eg, an
urge or an itch) with openness, curiosity, and willingness (eg,
notice the components of the sensation and allow them to come
and go without buying into evaluations of the sensations or at-
tempting to alter them). Teach students to identify their own personally held values and
notice how connection or disconnection with these values can
contribute to well-being or burnout experiences, respectively Students choose one of their own personally held values and
briefly reflect on how their behaviors have aligned with that
value during the day. Students select a personally held value that feels most important
to them in that moment and commit to taking one small and
achievable action toward that value during the day. Stage 1: Introductory Module During stage 1, participants used the app to complete an
introductory module that provided a conceptual framework from
which to understand the full Psychological Flexibility skill set. The module was divided into 7 sections (<10 min each), which
were presented in a fixed order and took approximately 1 hour
to complete. Progress was saved at the end of each section,
allowing participants to pause and resume the module if they
wished to complete it over multiple sittings. Section 1 content
included an introduction to burnout (definition, recognizing the
signs, and normalizing and destigmatizing) and well-being
(definition and importance of choosing behaviors that support
career sustainability). Sections 2 to 7 provided education about
each Psychological Flexibility skill set (see the screenshot in
Multimedia Appendix 1), including the role of psychologically
inflexible behaviors in burnout and psychological distress and
how flexibility processes may facilitate more adaptive responses
and psychologically healthy outcomes. Although the focus of
stage 1 was predominantly conceptual, each Psychological
Flexibility process was accompanied by at least one skill practice
activity (including personal value identification, metaphors,
mindfulness practice, awareness practice, thought defusion, Overview The intervention involved the delivery of individualized
ACTraining via an app (“BiSi: Build it. Sustain it.”) developed
by clinical psychologists (ED and BK). Existing Psychological
Flexibility training activities and concepts were adapted to suit
the context and target participant group. The app was created
in a low-code platform (Cogniss) that facilitated the delivery
of the outcome measures and intervention and the collection of
study data (including participants’ responses to outcome
measures and use data). Intervention content was delivered in
audio format with accompanying images and some supporting
written text. The ACTraining intervention was delivered in 2
stages. Further information regarding the Build it. Sustain it. app and intervention protocol has been published elsewhere
[57]. Before providing consent, students were informed that (1) data
collected during the study would be anonymous and retained
and stored for a minimum period of 5 years from completion
of the research, in accordance with the University of Newcastle
research data management policies; (2) deidentified data would
be analyzed, summarized, and presented in various formats (eg, JMIR Form Res 2023 | vol. 7 | e43263 | p. 5
(page number not for citation purposes) https://formative.jmir.org/2023/1/e43263 XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al perspective-shifting techniques, and behavioral activities). Participants were given 1 week to complete stage 1. JMIR Form Res 2023 | vol. 7 | e43263 | p. 6
(page number not for citation purposes) https://formative.jmir.org/2023/1/e43263 Stage 2: Individualized Skill Training Stage 2 was designed to provide students with on-demand access
to a library of short (3-8 min each) practical Psychological
Flexibility skill activities (20-25 activities per process), which
were targeted to their specific training needs each time they
accessed the app. Completion of stage 1 unlocked access to the
stage 2 dashboard (see the screenshot in Multimedia Appendix
2), which students could access at any time. Although there was
no requirement to complete a specific number of activities,
participants were sent daily reminder emails and encouraged to
practice regularly to optimize skill learning. Activities focused
on normalizing challenging internal experiences, strengthening
present-moment awareness, recognizing the influence of internal
experiences (including thoughts and emotions) on choices and
actions, learning to alter unworkable responses to internal
experiences, setting values-based goals, and developing more
flexible and value-aligned behavioral repertoires [43,45,58]. Table 1 provides a summary of the aims and an example activity
for each Psychological Flexibility skill set. Table 1. Aims and example activities for each Psychological Flexibility skill set. Example activity
Aim
Skill set
Guided mindfulness activity in whic
to specific aspects of their present-m
sounds, physical sensations, thought
Teach students to bring purposeful awareness to their present-
moment experiences and recognize how these experiences influ-
ence their choices (in everyday life and stressful situations)
Present-moment
awareness
Students practice responding flexibl
an action that contradicts a thought t
asked to think “I can’t lift my arm”
Teach students to distinguish between their direct experiences
and their thoughts about their experiences and respond more
flexibly to the latter by changing the contexts in which they ex-
perience their thoughts
Defusion
Students identify a “self-story” that c
response options in certain situation
tions that expand their behavioral re
stories. Teach students to recognize that their thoughts and emotions do
not define their identity but are transient aspects of their experi-
ence, which they can observe from a more stable and constant
sense of “self”
Self-as-context
(perspective
taking)
Students practice observing an unco
urge or an itch) with openness, curio
notice the components of the sensat
and go without buying into evaluatio
tempting to alter them). Teach students to identify unhelpful avoidance behaviors and
practice open, flexible, and adaptive ways of responding to inter-
nal discomfort
Acceptance
(willingness)
Students choose one of their own pe
briefly reflect on how their behavior
value during the day. Stage 2: Individualized Skill Training •
Struggling with your feelings: acceptance (willingness)
•
Unable to do what matters to you: committed action
•
Stuck in your thoughts: defusion
•
Stuck in autopilot or struggling to stay in the present moment: present-moment awareness
•
Disconnected from a sense of meaning or purpose: values
•
Stuck in stories about who you are or who you should be: self-as-context (perspective taking) steps were repeated until the participants elected to discontinue. Participants had access to stage 2 fo steps were repeated until the participants elected to discontinue. Participants had access to stage 2 for 3 weeks. Textbox 1. Stage 2 individualization screening question options and corresponding Psychological Flexibility processes. •
Struggling with your feelings: acceptance (willingness)
•
Unable to do what matters to you: committed action
•
Stuck in your thoughts: defusion
•
Stuck in autopilot or struggling to stay in the present moment: present-moment awareness
•
Disconnected from a sense of meaning or purpose: values
•
Stuck in stories about who you are or who you should be: self-as-context (perspective taking) Stage 2: Individualized Skill Training Teach students to choose effective and purposeful behaviors that
align with personally held values even when internal discomfort
is present; use direct experiences to recognize the difference be-
tween well-being–oriented action and inflexible persistence that
could increase burnout risk available for the Psychological Flexibility process they had
identified as having the most difficulty with on that occasion
(presented in a list). Students were then able to practice one of
the available skill activities, either by choosing from the list or
by allowing the app to make a random selection for them (see
the screenshot in Multimedia Appendix 4). Upon completion
of an activity, participants had the option to complete another
activity within the same Psychological Flexibility skill set. These Individual tailoring of Psychological Flexibility skill activity
delivery was implemented using a method adapted from a
similar previous study [27]. At each app log-in, participants
responded to a single-item screening question: which of the
following are you having the most difficulty with today? (see
the screenshot in Multimedia Appendix 3). Each response option
corresponded to 1 of the 6 Psychological Flexibility processes
(Textbox 1). After selecting a response, participants were
directed to a dashboard that provided access to all skill activities Individual tailoring of Psychological Flexibility skill activity
delivery was implemented using a method adapted from a
similar previous study [27]. At each app log-in, participants
responded to a single-item screening question: which of the
following are you having the most difficulty with today? (see
the screenshot in Multimedia Appendix 3). Each response option
corresponded to 1 of the 6 Psychological Flexibility processes
(Textbox 1). After selecting a response, participants were
directed to a dashboard that provided access to all skill activities JMIR Form Res 2023 | vol. 7 | e43263 | p. 6
(page number not for citation purposes) XSL•FO
RenderX XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al steps were repeated until the participants elected to discontinue. Participants had access to stage 2 for 3 weeks. steps were repeated until the participants elected to discontinue. Participants had access to stage 2 for 3 weeks. Textbox 1. Stage 2 individualization screening question options and corresponding Psychological Flexibility processes. JMIR Form Res 2023 | vol. 7 | e43263 | p. 7
(page number not for citation purposes) Overview We integrated design elements aimed at enhancing medical
students’ engagement with the app-based intervention. In
addition to individualization [27], this included the provision
of daily reminder emails [59], offering a variety of training
activities for each skill set [27,60], and providing opportunities
to engage in self-reflection while engaging in the educational
and skill practice components of the app [60]. We administered self-report psychological outcome measures
(Table 2) at t0 only. The purpose of administering these outcome
measures in this study was to evaluate the feasibility of using
the app delivery method to assess psychological outcomes of
interest in the planned efficacy trial and explore the potential
assessment burden to participants. Psychological outcome data
were also used to describe the baseline psychological
characteristics of this feasibility trial sample. https://formative.jmir.org/2023/1/e43263 https://formative.jmir.org/2023/1/e43263 XSL•FO
RenderX XSL•FO
RenderX Ditton et al JMIR FORMATIVE RESEARCH Table 2. Summary of outcome measure characteristics and internal consistency (Cronbach α) for this sample. Cronbach
Measure characteristics
Items, N
Outcome measure
Psychological outcomes
.84
16
Burnout—MBI-GS(S)a
[61]
•
Validity [62] and reliability have been demonstrated among medical students [63]. •
Respondents rate the frequency of each burnout experience using a 7-point Likert
scale. •
Provides summed total scores for each burnout factor; higher Eb and Cc and lower
AEd scores reflect a higher frequency of burnout experiences. .91
14
Well-being—MHC-SFe
[19]
•
Validity [19] and reliability (including internal consistency and test-retest reliability)
[64] have been demonstrated. •
Respondents rate the frequency of well-being experiences during the previous month
using a 6-point Likert scale. •
Provides average item scores for 3 well-being factors: EWBf, SWBg, and PWBh. •
Higher scores reflect a higher well-being. .89
24
Psychological Flexibility
and Inflexibility—MPFI-
SFi [54]
•
This scale has demonstrated validity (including convergent, predictive, and discrim-
inant validity between PFj and PIk scales [55]) and reliability (including internal
consistency [65] and responsiveness to change over time [54]). •
Respondents rate the frequency of PF and PI experiences during the past 2 weeks
using a 6-point Likert scale. •
Provides global PF and global PI composite scores. •
High PF scores reflect higher flexibility, and higher PI scores reflect higher inflexi-
bility. .91
21
Depression, anxiety, and
stress—DASS-21l [66]
•
Validity and reliability have been demonstrated [66,67]. •
Respondents rate the frequency of depression, anxiety, and stress symptoms experi-
enced during the past week using a 4-point Likert scale. Overview •
Provides subscale scores estimating the severity of depression, anxiety, and stress
symptoms [66] and a total score reflecting general negative affectivity or psycholog-
ical distress [67]. Feasibility outcomes
.81
10
App usability—SUSm [27]
•
Validity and reliability have been demonstrated [27]. •
Respondents rate the degree to which they agree with usability statements about the
app using a 5-point Likert scale (1=“strongly disagree” to 5=“strongly agree”). •
Provides a total score ranging from 0 to 100. •
Higher scores reflect higher usability (85-100=excellent, 73-84=good, 62-73=low
marginal, and <70=needs to be reviewed and improved) [68]. •
In accordance with recommendations by other authors, we amended item wording
to suit our intervention context and audience (eg, “system” changed to “App”) [69]. .93
32
User Experience Assess-
ment part 1
•
Respondents rate their level of agreement with each statement about experiences of
engaging with the intervention app using a 5-point Likert scale (1=“strongly disagree”
to 5=“strongly agree”). •
Provides average user experience score, where higher scores reflect more favorable
intervention experiences. •
An additional 2 items (not included in average user experience rating) assessed stu-
dents’ perceptions of the duration of the intervention (1=“way too short,” 2=“too
short,” 3=“just right,” 4=“too long,” and 5=“way too long”) and frequency of the
reminder emails (1=“way too infrequent,” 2=“too infrequent,” 3=“just right,” 4=“too
frequent,” and 5=“way too frequent”). N/An
8
User Experience Assess-
ment part 2
•
Participants are asked to provide short-answer responses to open-ended questions
about their experiences of using the app. .90
13
Learning experiences as-
sessment
•
Questions were adapted from Kinnunen et al [70] (items altered to suit learning ob-
jectives of this intervention). •
Participants rate the degree to which they agree with statements about their learning
experiences using a 5-point Likert scale (1=“strongly disagree” to 5=“strongly
agree”). •
The scale provides an average item score. •
Higher scores indicate higher perceived skill learning. JMIR Form Res 2023 | vol. 7 | e43263
https://formative.jmir.org/2023/1/e43263
(page number not for citation purp
L FO Table 2. Summary of outcome measure characteristics and internal consistency (C
Measure characteristics
Items, N
Outcome measure
Psychological outcomes
16
Burnout—MBI-GS(S)a
[61]
•
Validity [62] and reliability hav
•
Respondents rate the frequency
scale. •
Provides summed total scores f
AEd scores reflect a higher freq
14
Well-being—MHC-SFe
[19]
•
Validity [19] and reliability (inc
[64] have been demonstrated. JMIR Form Res 2023 | vol. 7 | e43263 | p. 8
(page number not for citation purposes) Overview •
Respondents rate the frequency
using a 6-point Likert scale. •
Provides average item scores fo
•
Higher scores reflect a higher w
24
Psychological Flexibility
and Inflexibility—MPFI-
SFi [54]
•
This scale has demonstrated val
inant validity between PFj and P
consistency [65] and responsive
•
Respondents rate the frequency
using a 6-point Likert scale. •
Provides global PF and global P
•
High PF scores reflect higher fl
bility. 21
Depression, anxiety, and
stress—DASS-21l [66]
•
Validity and reliability have bee
•
Respondents rate the frequency
enced during the past week usin
•
Provides subscale scores estima
symptoms [66] and a total score
ical distress [67]. Feasibility outcomes
10
App usability—SUSm [27]
•
Validity and reliability have bee
•
Respondents rate the degree to w
app using a 5-point Likert scale
•
Provides a total score ranging f
•
Higher scores reflect higher usa
marginal, and <70=needs to be
•
In accordance with recommend
to suit our intervention context
32
User Experience Assess-
ment part 1
•
Respondents rate their level of a
engaging with the intervention ap
to 5=“strongly agree”). •
Provides average user experienc
intervention experiences. •
An additional 2 items (not inclu
dents’ perceptions of the duratio
short,” 3=“just right,” 4=“too lo
reminder emails (1=“way too in
frequent,” and 5=“way too freq
8
User Experience Assess-
ment part 2
•
Participants are asked to provid
about their experiences of using
13
Learning experiences as-
sessment
•
Questions were adapted from K
jectives of this intervention). •
Participants rate the degree to w
experiences using a 5-point Lik
agree”). •
The scale provides an average i
•
Higher scores indicate higher p
https://formative.jmir.org/2023/1/e43263 Table 2. Summary of outcome measure characteristics and internal consistency (Cronbach α) for this sample. Measure characteristics
Items, N
Outcome measure Cronbach α https://formative.jmir.org/2023/1/e43263 Frequency of App Use Frequency of app use was defined as the number of log-ins
during the study and the number of skill activities accessed and
completed. Engagement In the planned efficacy trial, we aim to explore whether
engagement with the intervention app improves medical
students’Psychological Flexibility and Inflexibility and evaluate
whether changes in these processes mediate burnout and
well-being outcomes [57]. As there is growing evidence that
Psychological Flexibility and Inflexibility are “conceptually
distinct” processes that can exert independent effects on
outcomes and may respond differently to interventions [54,55],
we selected the Multidimensional Psychological Flexibility
Index-Short Form [54], which assesses Psychological Flexibility
and Inflexibility as separate processes rather than as a single
dimension [55]. This will facilitate the evaluation of potential
differential intervention and mediation effects in the future
efficacy study. Engagement at key points in the study was defined as the
number of participants who (1) downloaded the app, (2)
completed all outcome measures at t0, (3) completed the
introductory module at stage 1, (4) completed all outcome
measures at t1, (5) completed at least one skill training activity
at stage 2, (6) completed all outcome measures at t2, and (7)
were still using the app at least 2 weeks after their initial sign-up. App Functionality The app collected participants’ use data, including which
assessment and intervention components were accessed and in
which order. This allowed us to observe whether the app
facilitated participants’ progress through the study protocol in
the intended way. We defined the app as functional if the
outcome measures and intervention components were delivered
to all participants at the intended time and in the intended order,
if individualization procedures were implemented as intended,
if at least one participant completed the study protocol in its
entirety, and if the app generated data output required to evaluate
intervention outcomes. Behavioral Use Data Improving burnout outcomes is a core goal of this intervention,
and burnout is the primary outcome for the planned efficacy
trial. We assessed burnout using the gold-standard measure, the
Maslach Burnout Inventory [61]. Of the range of versions
available, the Maslach Burnout Inventory General Survey for
Students [61] was considered the most appropriate for this
cohort. Well-being Improving well-being is a core goal of this intervention, and
well-being is an outcome of interest to the planned efficacy
trial. We assessed this outcome using the short form of the
Mental Health Continuum [19]. Depression, Anxiety, and Stress The app captured the time of day of each log-in, which we
categorized using the following definitions: early morning (5
AM to 9 AM), morning (9 AM to noon), afternoon (noon to 5
PM), evening (5 PM to 9 PM), late night (9 PM to midnight),
and after midnight (midnight to 5 AM). In addition to burnout and well-being, the planned efficacy trial
aims to explore the potential benefits of the intervention app to
other psychological health outcomes relevant to medical
students. As such, the Depression, Anxiety, and Stress Scale-21
[66] was administered to evaluate medical students’
psychological health outcomes more broadly. Feasibility outcomes .81
0
•
Validity and reliability have been demonstrated [27]. •
Respondents rate the degree to which they agree with usability statements about the
app using a 5-point Likert scale (1=“strongly disagree” to 5=“strongly agree”). •
Provides a total score ranging from 0 to 100. •
Higher scores reflect higher usability (85-100=excellent, 73-84=good, 62-73=low
marginal, and <70=needs to be reviewed and improved) [68]. •
In accordance with recommendations by other authors, we amended item wording
to suit our intervention context and audience (eg, “system” changed to “App”) [69]. .93
2
•
Respondents rate their level of agreement with each statement about experiences of
engaging with the intervention app using a 5-point Likert scale (1=“strongly disagree”
to 5=“strongly agree”). •
Provides average user experience score, where higher scores reflect more favorable
intervention experiences. •
An additional 2 items (not included in average user experience rating) assessed stu-
dents’ perceptions of the duration of the intervention (1=“way too short,” 2=“too
short,” 3=“just right,” 4=“too long,” and 5=“way too long”) and frequency of the
reminder emails (1=“way too infrequent,” 2=“too infrequent,” 3=“just right,” 4=“too
frequent,” and 5=“way too frequent”). N/An
•
Participants are asked to provide short-answer responses to open-ended questions
about their experiences of using the app. .90
3
•
Questions were adapted from Kinnunen et al [70] (items altered to suit learning ob-
jectives of this intervention). •
Participants rate the degree to which they agree with statements about their learning
experiences using a 5-point Likert scale (1=“strongly disagree” to 5=“strongly
agree”). •
The scale provides an average item score. •
Higher scores indicate higher perceived skill learning. N/An
•
Participants are asked to provide short-answer responses to open-ended questions
about their experiences of using the app. •
Higher scores indicate higher perceived skill learning. https://formative.jmir.org/2023/1/e43263 XSL•FO
RenderX Ditton et al JMIR FORMATIVE RESEARCH aMBI-GS(S): Maslach Burnout Inventory General Survey for Students. bE: exhaustion. cC: cynicism. dAE: academic efficacy. eMHC-SF: Mental Health Continuum-Short Form. fEWB: emotional well-being. gSWB: social well-being. hPWB: psychological well-being. iMPFI-SF: Multidimensional Psychological Flexibility Index-Short Form. jPF: Psychological Flexibility. kPI: Psychological Inflexibility. lDASS-21: Depression, Anxiety, and Stress Scale-21. mSUS: System Usability Scale. nN/A: not applicable. aMBI-GS(S): Maslach Burnout Inventory General Survey for Students. bE: exhaustion. cC: cynicism. dAE: academic efficacy. eMHC-SF: Mental Health Continuum-Short Form. fEWB: emotional well-being. gSWB: social well-being. hPWB: psychological well-being. iMPFI-SF: Multidimensional Psychological Flexibility Index-Short Form. jPF: Psychological Flexibility. kPI: Psychological Inflexibility. JMIR Form Res 2023 | vol. 7 | e43263 | p. 9
(page number not for citation purposes) Feasibility outcomes lDASS-21: Depression, Anxiety, and Stress Scale-21. mSUS: System Usability Scale. nN/A: not applicable. aMBI-GS(S): Maslach Burnout Inventory General Survey for Students. b bE: exhaustion. cC: cynicism. dAE: academic efficacy. eMHC-SF: Mental Health Continuum-Short Form. fEWB: emotional well-being. gSWB: social well-being. hPWB: psychological well-being. iMPFI-SF: Multidimensional Psychological Flexibility Index-Short Form. j iMPFI-SF: Multidimensional Psychological Flexibility Index-Short Form. jPF: Psychological Flexibility. kPI: Psychological Inflexibility. l lDASS-21: Depression, Anxiety, and Stress Scale-21. mSUS: System Usability Scale. nN/A: not applicable. Quantitative Data Descriptive analyses (including mean, SD, mode, minimum,
and maximum) of quantitative demographic, psychological,
feasibility, and behavioral engagement outcome data were
performed using the Jamovi statistical software (version 2.3.0)
[75]. Demographics Figure 1 shows that 19 medical students enrolled and 11 (58%)
actively engaged in the study and provided user experience
feedback. Of the 11 actively engaged participants, 10 (91%)
identified as female, 10 (91%) were enrolled as domestic
students, and 2 (18%) were Aboriginal individuals. Participants
were aged between 20 and 23 (mean 21, SD 1.2) years. The
average time engaged in the workforce was 4.5 years (SD 2.3),
and medicine was the first career for most (10/11, 91%)
participants. In total, 73% (8/11) of the participants reported
having experienced burnout in the past. Actively engaged
participants rated their physical health as good (mean 3.8, SD
0.4). Diet (mean 3.6, SD 0.5) and self-care (mean 3.5, SD 0.7)
ratings fell between average and good. Qualitative Data Participants’ short-answer responses to the open-ended user
experience questions were evaluated qualitatively. Responses
were independently reviewed by 2 members of the research
team (ED and BK) and coded thematically according to their
relevance to usability, accessibility, external factors (eg, time),
behavioral factors (eg, practice), or any of the TFA indicators
(affective attitude, perceived effectiveness, intervention
coherence, self-efficacy, opportunity costs, burden, and
ethicality). Each response was coded as a barrier to or facilitator
of engagement or a positive or negative evaluation of an aspect
of the intervention. The coding was then reviewed together to
determine common themes and subthemes in a reiterative
process. Learning Experiences As part of assessing the feasibility of adapting ACTraining into
a digital learning format, we identified key learning goals and
asked medical students to rate the degree to which they felt that
these had been achieved by engaging with the app. A learning
experiences assessment previously used in a similar web-based
intervention study [70] was adapted to align with the focus of
this app (Multimedia Appendix 6 [70]). Questions related to
medical students’self-reported ability to identify Psychological
Inflexibility processes and apply Psychological Flexibility skills
across each of the core processes. Of the participants lost to follow-up, 50% (4/8) identified as
male, reflecting that most of the enrolled male students (4/5,
80%) discontinued the study before engaging in or providing
feedback on the intervention. Although the demographic
characteristics of the students lost to follow-up were generally
similar to those of the students who engaged in the intervention,
we noted that reported self-care was lower for students who
discontinued early (mean 2.8, SD 0.7). Self-report Measures of Usability and User Experiences Self-report usability and user experience measures (Table 2)
were administered at t1 (to obtain students’ feedback on the
intervention following the stage 1 introductory module) and t2
(to obtain feedback following the stage 2 individualized skill
training access period). https://formative.jmir.org/2023/1/e43263 JMIR Form Res 2023 | vol. 7 | e43263 | p. 9
(page number not for citation purposes) XSL•FO
RenderX XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al thumbs-up or thumbs-down icon). This method of evaluating
user experiences of intervention content has been used in
previous digital intervention studies [74]. App Interface Usability We assessed medical students’ satisfaction with the usability
of the app as subjective perceptions of the functionality of a
digital psychological intervention can influence engagement
[26,71]. The System Usability Scale (SUS) is a valid and reliable
measure of this outcome [72] and is the most frequently used
subjective measure of program usability [71]. User Experiences We used the theoretical framework of acceptability (TFA) [31]
to guide the assessment of user experiences with the
intervention. The TFA is a comprehensive research-based model
that recommends evaluating participant-rated acceptability of
health care interventions using 7 emotional and cognitive
indicators:
affective
attitude,
perceived
effectiveness,
intervention coherence, self-efficacy, opportunity costs, burden,
and ethicality [31]. As there were no available standardized
TFA measures, we used the definitions of the 7 indicators to
inform the development of a 2-part User Experience Assessment
for the purpose of this study (see Multimedia Appendix 5 for
indicator
definitions
and
assessment
questions). The
development of the questions was further guided by research
related to factors that affect the acceptability of psychological
interventions among medical students (eg, time [28], privacy
[6,47], and accessibility and flexibility [28]), health care
interventions (eg, affective experiences and satisfaction [31]),
and digital interventions (eg, self-guided [26], expectation of
benefit [73], quality, and content relevance [26]). Where
appropriate, questions were framed with respect to the outcomes
targeted by the intervention (ie, burnout and well-being) to
evaluate factors such as the perceived effectiveness and
relevance of this approach among medical students. Part 1 asked
participants to indicate their level of agreement with statements
about their experiences of using the Psychological Flexibility
app. We defined items with an average score of <3.8 as aspects
of the intervention that might require revision before the planned
efficacy trial. This value was selected as it represented an
average rating of a little below agree. We defined items with
an average score of >4 (“agree”) as intervention strengths. Part
2 consisted of 8 short-answer questions, which were included
to collect feedback regarding facilitators of and barriers to
engagement as well as other information that we may not have
considered. Intervention Harms Participants were invited to report concerns or harms
experienced during the study using contact links provided within
the app and via email communications sent during the trial (eg,
daily reminders). https://formative.jmir.org/2023/1/e43263 Engagement Of the 19 participants who were enrolled in the study, 15 (79%)
downloaded the app and created an account, 14 (74%) completed
all t0 outcome measures, 11 (58%) completed stage 1 and the
t1 outcome measures, 8 (42%) engaged in stage 2, and 3 (16%)
completed the t2 outcome measures (Figure 1). Of the
participants who downloaded the app and created an account,
47% (7/15) continued to use the app for at least 2 weeks from
the date of their initial log-in. Psychological Flexibility and Inflexibility Multidimensional Psychological Flexibility Index-Short Form
scores indicated that, on average, participants had had
experiences consistent with Psychological Flexibility often to
very often during the previous 2 weeks (mean 3.71, SD 0.67),
which was comparable with a general population sample (mean
3.83) [77]. On average, students reported that they had often
had experiences consistent with Psychological Inflexibility
during the previous 2 weeks (mean 3.03, SD 0.47), which was
slightly more frequent than the general population sample (mean
2.73) [77]. https://formative.jmir.org/2023/1/e43263 App Functionality The app generally functioned as intended during the trial. Use
data demonstrated that outcome assessments and intervention
components were delivered in the intended order and at the
intended time, individualization procedures were implemented
as planned, 16% (3/19) of the participants successfully
completed the intervention protocol in its entirety, and the app
generated the data output required to evaluate intervention
outcomes. We noted that a system glitch resulted in participants
being sent the daily reminder email up to 4 times each day. Frequency of App Use Students who were actively engaged in the study (11/19, 58%)
logged into the app between 2 and 10 times (total=70; mean
6.36, SD 2). Log-in frequency diminished between stage 1
(total=41; mean 3.73, SD 1) and stage 2 (total=29; mean 2.64,
SD 2). It took students between 1 and 5 sittings to complete all
the stage 1 activities. Participants who logged in during stage Well-being On average, participants’ emotional (mean 11.36, SD 2.54),
social (mean 13.45, SD 4.06), and psychological (mean 19.55,
SD 4.57) well-being scores were slightly lower than those of a
comparable published sample of medical students (emotional
well-being mean 12.79; social well-being mean 14.84;
psychological well-being mean 24.42) [76]. Skill Activity Feedback After completing a skill activity during stage 2, participants
were asked to rate whether they liked the activity using a
single-item measure assessed on a binary scale (using a https://formative.jmir.org/2023/1/e43263 JMIR Form Res 2023 | vol. 7 | e43263 | p. 10
(page number not for citation purposes) JMIR Form Res 2023 | vol. 7 | e43263 | p. 10
(page number not for citation purposes) XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al Psychological Characteristics
Summary
Table 3 shows baseline psychological characteristics of the
participants who actively engaged in the study. Table 3. Baseline psychological characteristics of actively engaged participants (N=11). Range
Mean (SD)
Outcome
Burnout
7-24
16.00 (6.24)
Emotional exhaustion
5-16
8.45 (3.50)
Cynicism
18-32
24.82 (5.90)
Academic efficacy
Well-being
6-14
11.36 (2.54)
Emotional
8-20
13.45 (4.06)
Social
14-27
19.55 (4.57)
Psychological
2.67-5
3.71 (0.67)
Psychological Flexibility
2.25-3.92
3.03 (0.47)
Psychological Inflexibility
0-20
8.55 (6.82)
Depression
0-22
8.18 (7.12)
Anxiety
0-32
14.4 (10.23)
Stress Table 3 shows baseline psychological characteristics of the
participants who actively engaged in the study. Table 3 shows baseline psychological characteristics of the
participants who actively engaged in the study. Psychological Characteristics and stress (mean 10.36, SD 10.23) at levels higher than the
general population averages (depression: mean 6.34, SD 6.97;
anxiety: mean 4.7, SD 4.91; stress: mean 10.11, SD 7.91) [66]. Feasibility Outcomes Feasibility Outcomes JMIR Form Res 2023 | vol. 7 | e43263 | p. 11
(page number not for citation purposes) Burnout Mean total scores for exhaustion (mean 16.00, SD 6.24) and
cynicism (mean 8.45, SD 3.50) for actively engaged students
were comparable with those of a recently published sample of
medical students who, by subjective self-report, were not
experiencing burnout (exhaustion mean 14.96; cynicism mean
7.59) [63]. Conversely, our sample’s mean total score for
academic efficacy (mean 24.82, SD 5.90) was comparable with
that of a sample of medical students who believed themselves
to be experiencing burnout (mean 24.81) [63]. App Interface Usability The average total SUS score at t1 (mean 85.0, SD 9.3) indicates
excellent usability [68]. Individual participant SUS scores
ranged between 70 (low marginal) and 96 (excellent), indicating
that there were substantial differences in participants’
satisfaction with the usability of the app interface. Similarly, at
t2, individual usability ratings varied, ranging between 72 and
96. The qualitative feedback provided by participants at t1 offers
insights into the factors that may have influenced this variability. Many students reported feeling satisfied by the ease of use and
navigation, logical structure and flow of the app interface,
provision of simple and clear instructions, and continuation of
audio play when their device auto-locked. However, app
usability elements that generated dissatisfaction included lack
of access to a dashboard or home screen during stage 1,
insufficient feedback regarding how far students had progressed
through the introductory module, having to complete module
components in a fixed order rather than being able to navigate
flexibly through the concepts, and the delivery of reminders via
email rather than in-app push notifications. Although some
students favored the audio delivery of content, others reported
that having a written version of all content would have improved
accessibility (eg, audio content was a barrier to usability when
in public, and audio content delivery did not match personal
learning styles for some). We identified 5 user experience items with average scores below
the 3.8 cutoff at t1, indicating that these intervention elements
might require additional attention before the larger trial. These
items were enjoyed using the app, held interest and attention,
received amount of training needed to achieve the goals that
are important to me, felt confident using the skills in everyday
life, and I believe these skills will help me prevent burnout. Qualitative feedback provided by 18% (2/11) of the participants
indicated that they did not feel that burnout prevention should
be the focus of the intervention as the techniques were “helpful
for many different things.” Most participants (9/11, 82%) indicated that the 1-hour
introductory module was slightly too long, whereas the
remaining 18% (2/11) of participants felt that the duration was
just right. However, qualitative feedback indicated that some
participants felt that the content was as concise as it could be Overview At t1, self-report measures of user experiences were completed
by 100% (11/11) of the participants who completed stage 1. At
t2, these measures were completed by 38% (3/8) of the
participants who engaged in stage 2. Owing to the low response
rate at t2, we report the minimum and maximum scores for each
outcome instead of the average scores. The average participant scores for each user experience question
at t1 are presented in Multimedia Appendix 6. We identified
several intervention strengths (average item scores of >4). Strengths related to the app delivery format and interface
included quality, visual appearance, web-based availability,
ability to access at a personally convenient time, maintenance
of privacy, and did not get in the way of other important life
activities. Strengths related to the ACTraining intervention
content included opportunities for self-reflection, content
relevance, anticipated benefits of continued skill use, anticipated
benefits to well-being during career, concepts were easy to
understand, felt confident performing the skill activities while
using the app, felt capable of dealing with any challenging
internal experiences that arose while using the app, aligned
with personal values, and the time and effort invested in the
Psychological Flexibility training was worthwhile. After
completing the introductory module, most students (8/11, 73%)
agreed or strongly agreed that they would like to use the app
again in the future (mean 3.91, SD 0.94). Depression, Anxiety, and Stress The average Depression, Anxiety, and Stress Scale-21 scores
indicated that medical students in this trial were experiencing
depression (mean 8.55, SD 6.82), anxiety (mean 8.18, SD 7.12), XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al medical students used the app most frequently between 9 PM
and midnight (21/70, 30%). Although reasonably infrequent
(5/70, 7%), medical students occasionally used the app after
midnight. 2 (8/11, 73%) accessed a total of 24 skill activities (mean 2.18,
SD 1), of which 16 (67%) were completed (mean 1.45, SD 1). Time of App Use Table 4 shows that 56% (39/70) of app use was distributed fairly
evenly throughout the day (between 9 AM and 9 PM) and that Table 4. Frequency of app use by time of day (percentage of total log-ins; N=70). Log-in frequency, n (%)
Time of log-in
5 (7)
Early morning (5 AM to 9 AM)
12 (17)
Morning (9 AM to noon)
14 (20)
Afternoon (noon to 5 PM)
13 (19)
Evening (5 PM to 9 PM)
21 (30)
Late night (9 PM to midnight)
5 (7)
After midnight (midnight to 6 AM)
Self-report Data
Overview
0.34), indicating that participants who engaged in stage 1
generally found the intervention to be acceptable with respect
to the experiences assessed. Similar findings were observed at
t (range 3 3 4 6) Table 4. Frequency of app use by time of day (percentage of total log-ins; N=70). After midnight (midnight to 6 AM) 0.34), indicating that participants who engaged in stage 1
generally found the intervention to be acceptable with respect
to the experiences assessed. Similar findings were observed at
t2 (range 3.3-4.6). 0.34), indicating that participants who engaged in stage 1
generally found the intervention to be acceptable with respect
to the experiences assessed. Similar findings were observed at
t2 (range 3.3-4.6). https://formative.jmir.org/2023/1/e43263 JMIR Form Res 2023 | vol. 7 | e43263 | p. 12
(page number not for citation purposes) Feasibility, Engagement, and User Experiences Feasibility, Engagement, and User Experiences The qualitative user experience feedback at t1 generally reflected
the quantitative findings. Most students who completed stage
1 provided favorable feedback about the Psychological
Flexibility intervention content, describing the app as “great,”
“useful,” and “helpful” and suggesting that the training “needs
to be widely available.” One of the reported benefits of the
app-based delivery was that students liked being able to engage
in short sections and pick up where they left off rather than
having to complete the entire intervention at once. Students
reported enjoying the skill activities, stating that they “provided
context and demonstrated how to use [the skills],” and some
students requested “more interactive components and practice
activities” and more “clinical examples.” T1 qualitative data
also highlighted the self-efficacy challenges faced by students
when accessing Psychological Flexibility skill training via an
app, including feeling “too overwhelmed” in real-world
situations to use the skills, not recognizing opportunities to use
the skills when they arose, and not knowing which skills to
apply in which situations. A participant reported feeling that
they had learned the Psychological Flexibility “concepts” but
not the “behavior.” These findings align with the fact that stage
1 focused on conceptual learning and participants had only
engaged in minimal skill training at this stage of the intervention. Students also reported that a key barrier to using the app was
having time available to do so. This early implementation trial with a small group of Australian
medical students provided preliminary support for the feasibility
of an individualized ACTraining intervention app for well-being
and burnout as well as user experience feedback that may be
used to guide the ongoing development of the app and future
research. In relation to our first study aim, we demonstrated
that the app could successfully administer outcome assessments,
ACTraining intervention components, and Psychological
Flexibility skill individualization procedures. These functional
feasibility data were supported by subjective user experience
feedback provided by medical students who actively engaged
with the app. The interface was, on average, rated as having
excellent usability, and students responded favorably to
accessibility factors related to the app-based delivery (eg,
maintenance of privacy and ability to access at any time). Furthermore, we demonstrated the feasibility of using an app
to deliver ACTraining content and skill training to a sample of
medical students in a way that they found easy to understand
and acceptable. User Experiences At t1, the average total user experience ratings ranged between
slightly agree (3.4) and strongly agree (4.8; mean 4.05, SD https://formative.jmir.org/2023/1/e43263 JMIR Form Res 2023 | vol. 7 | e43263 | p. 12
(page number not for citation purposes) XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al without compromising the value of the intervention. At both
time points, participants indicated that they did not find
completing the outcome questionnaires to be burdensome. without compromising the value of the intervention. At both
time points, participants indicated that they did not find
completing the outcome questionnaires to be burdensome. Skill Activity Feedback Students “liked” 88% (14/16) of the activities completed during
stage 2. Learning Experiences At t1, participants’learning experience assessment scores ranged
from 2.92 (slightly agree) to 4.1 (agree; mean 3.7, SD 0.51). The most frequently endorsed rating for 92% (12/13) of the
learning experiences was agree (mode=4). At t2, scores ranged
from 2.62 to 4, with a participant indicating that they did not
learn the skills targeted by the intervention and 18% (2/11) of
the participants agreeing that they had learned the skills. Previous research evaluating an app-delivered ACTraining
intervention indicated that disengagement is not necessarily an
unfavorable outcome and might reflect the successful
achievement of an individual’s learning goals [27]. User
experience findings suggest that this was not the case in this
sample. Learning experience scores showed that medical
students who completed the introductory module agreed that
they had learned most of the Psychological Flexibility skills
targeted by the ACTraining app to some extent. However, on Feasibility, Engagement, and User Experiences More broadly, the feasibility of delivering psychological skill
training via an app is contingent on the degree to which this
method can facilitate and maintain end-user engagement with
the intervention content. We found that 42% (8/19) of the
medical students who enrolled in the study disengaged without
completing the introductory module, and 50% (4/8) of those
students did not proceed as far as downloading or signing up
to the app. These students reported lower average self-care
ratings than those who completed the introductory module, and
future research should explore whether existing self-care
behavioral patterns could impede early engagement in
psychological intervention apps. Regarding maintenance of
engagement, the frequency of app log-ins diminished between
stages 1 and 2. Less than half (7/15, 47%) of the students who
downloaded the app were still engaged after 2 weeks. Those
who used the app during stage 2 completed <2 skill activities
on average despite “liking” most activities completed. Although
the observed pattern of disengagement over time is common
for digital and app-based psychological interventions [30,78],
it is incongruent with the fact that students who completed the
introductory module generally reported that they would like to
use the app in the future. These findings reinforce the need for
a detailed formal evaluation of end-user experiences to better
understand factors that may affect feasibility [1] and guide app
intervention development, which was the second aim of this
study. Qualitative data collected at t2 provided further insights into the
perceptions of a small selection of participants regarding the
stage 2 individualized skill training. Students liked the app
interface and the short duration of skill activities. However, the
high frequency of reminders resulting from an app glitch was
reported as unsatisfactory and frustrating. A participant
suggested that reminders should be delivered at the end of the
workday as this would align better with medical students’
schedules and reduce burden. Barriers to engagement in skill
training included life commitments, time, forgetting, and the
fact that the training had not yet become a priority or a habit. https://formative.jmir.org/2023/1/e43263 JMIR Form Res 2023 | vol. 7 | e43263 | p. 13
(page number not for citation purposes) Intervention Harms Given that the
intervention was intended to have relevance to both outcomes,
this feedback suggests that content might not have aligned
sufficiently with factors that participants perceived to be relevant
to their burnout experiences. A future step in the development
process of this app will involve consultation with medical
student end users regarding which aspects of their academic
and clinical experiences they consider to be most associated
with burnout risk. Intervention content can then be adjusted to
demonstrate how Psychological Flexibility skills might be
implemented to mitigate these risk factors, which could increase
perceived relevance and engagement. Some students astutely
recognized the potential for Psychological Flexibility to offer
benefits beyond burnout prevention and proposed that the
intervention shift its focus and messaging to the broader
relevance of these skills. This approach may increase the
engagement of medical students interested in well-being and
other outcomes. However, removing the burnout prevention
focus could also result in failure to engage students who
self-identify as being at risk as well as missing opportunities to
train important risk-mitigating applications of Psychological
Flexibility skills. Future research might explore whether
engagement is improved by using the app to assess which
outcomes are most important to individual medical students and
individualizing the focus of intervention content based on these
preferences. Feedback provided by medical students who actively
participated in the intervention indicated that the short and
resumable nature of the app-delivered skill activities facilitated
engagement and that the time invested was worthwhile. However, time factors and demands related to medical studies
were reported barriers to app use, which is consistent with
previous research evaluating an app-delivered psychological
intervention for medical residents [22]. Participant feedback
suggested that this might be mitigated by amending the format
and timing of reminders, such as push notifications at the end
of the day, when there are fewer competing demands associated
with medical studies. This approach is supported by the observed
timing of app engagement occurring frequently after 9 PM. Although this intervention focused on strategies to support
well-being behaviors in the context of time pressures and
demands, future interventions should introduce these
components during the early stages of training, when app
engagement is at its highest. Performing self-reflection and skill-learning tasks without
in-person guidance is a potential challenge for individuals
engaging in a psychological intervention using a stand-alone
app [26]. Intervention Harms No harms were reported during this trial. https://formative.jmir.org/2023/1/e43263 JMIR Form Res 2023 | vol. 7 | e43263 | p. 13
(page number not for citation purposes) JMIR Form Res 2023 | vol. 7 | e43263 | p. 13
(page number not for citation purposes) XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al the app (9/11, 82%) reported finding the 1-hour introductory
module slightly too long. Given that this was very brief
compared with face-to-face ACTraining interventions [79-81]
and that most students reported wanting further training,
reducing the volume of introductory content could affect future
efficacy and is not an ideal solution. Rather, qualitative user
experience feedback highlighted aspects of the app interface
that may have contributed to this module feeling subjectively
long. Delivery of content in a fixed order was a frustration for
many students, who reported finding it difficult to track how
far they had progressed through the module and would have
preferred the autonomy to move between topics using a home
screen. Students indicated that they would have liked more
interactive components and opportunities to practice skills and
self-reflection, suggesting that the introductory content could
have been delivered in a more engaging format. Furthermore,
although many students responded favorably to the
audio-delivered content, others reported that the availability of
a written version would have increased accessibility and
engagement. Medical students’preferences for interacting with
app-based media appeared to affect their experiences of
participating in the intervention. When adapting established
psychological intervention models to app-based intervention
models, future research may explore whether evaluating and
accommodating medical students’interface-related preferences
strengthens interest and engagement. average, participants only slightly agreed that they had received
the amount of training needed to achieve the outcomes that were
important to them, and qualitative feedback indicated that they
wanted more opportunities for skill practice. Thus, declining
engagement following the introductory module was likely
related to other factors. average, participants only slightly agreed that they had received
the amount of training needed to achieve the outcomes that were
important to them, and qualitative feedback indicated that they
wanted more opportunities for skill practice. Thus, declining
engagement following the introductory module was likely
related to other factors. Medical students who completed the introductory module
predominantly reported finding the Psychological Flexibility
concepts and skills relevant, helpful, and worthwhile. Students
tended to perceive that the skills had greater benefits and
relevance to well-being than burnout prevention. https://formative.jmir.org/2023/1/e43263 Limitations Although
medical students who completed the outcome measures did not
find them to be burdensome, this may not have been the case
for those who disengaged. The user experience findings were
biased toward the opinions of medical students who were
actively engaged in the intervention. Future feasibility studies
should adopt a secondary method of follow-up data collection
to assess the experiences of students who discontinue app use
to facilitate a better understanding of engagement barriers. This study is the first to report detailed feedback from medical
student end users regarding their experience of engaging in an
app-delivered psychological intervention. Although specific
findings may not be generalizable beyond this sample and app,
our observations and evaluation process have potential relevance
to researchers in the emerging field of app-delivered
psychological interventions for medical student well-being. We
demonstrated that making an intervention accessible to medical
students via an app does not guarantee that they will access it,
even when their self-reported intention is to do so, and that
formal evaluation of user experiences across a range of domains
may facilitate the identification of contributing factors. Our
findings suggest that it may be useful for intervention developers
to assess medical students’
preferences regarding the
functionality and usability aspects of app interfaces as well as
individual differences in learning goals, baseline skills, and
confidence. Failure to understand user experiences could result
in disengagement for reasons unrelated to the intervention
model, leading to missed opportunities to fully develop and
deploy potentially valuable psychological skill training [1]. We
recommend that future researchers incorporate formal evaluation
of medical students’ subjective user experiences into the
intervention development process (including quantitative and
qualitative assessments) to better understand and address factors
that might affect engagement and disengagement. The collection of user experience data using a nonstandardized
questionnaire written for the purpose of this study was a
limitation. Although the User Experience Assessment was
theory-driven, it is possible that researcher subjectivity might
have biased its development and response interpretation. Given
the lack of quantitative scales based on the TFA [31], we have
made this assessment available (Multimedia Appendix 6) to
facilitate further validation and refinement of feasibility
assessment strategies for psychological app development studies. The skew toward female participants and small sample size
prevent the generalizability of the observed findings to medical
students more broadly. Limitations Despite its limitations, this study reports detailed user experience
data that have been largely absent from the literature on digital
psychological interventions for medical students [1] and outlines
a process for the important step of assessing feasibility outcomes
as part of app development. The findings support the feasibility
of implementing this app in a larger efficacy trial and provide
user experience feedback that could be used to improve the
intervention
and
strengthen
engagement. Intervention
development was driven by research suggesting the relevance
of Psychological Flexibility skills to medical students with
respect to burnout and well-being [6,47-50] and the potential
benefits of app-delivered psychological skill training for this
group [1,6,12,26-29]. Although this is early-phase work, the
study provides preliminary support for the feasibility of
delivering an ACTraining intervention to medical students using
a stand-alone app and supports the value of further evaluation
of this approach in burnout prevention and well-being research. Psychological Flexibility has recently been described as “the
cornerstone of psychological health and resiliency” [82] because
of its broad well-being benefits. With continued evaluation and
refinement, ACTraining apps offer a promising approach to
facilitating medical students’ development of these important
skills, which could be useful in the context of unavoidable
academic and occupational stressors. Although this trial had the full support of the universities in
which it was conducted, the intervention was intentionally
distanced from students’medical education programs to prevent
perceived participation coercion. Although important from a
research ethics perspective, this meant that the app was delivered
in isolation without external contextual factors that might have
facilitated engagement. For example, delivery as a formal part
of medical education training could normalize and legitimize
the value of well-being skill training, which may strengthen
students’ justification for prioritizing and allocating time for
engagement [5,6]. There is support for individual skill training
interventions to be formally incorporated into broader well-being
and burnout prevention initiatives within medical education
[10], and future research should explore whether this approach
could strengthen engagement in app-based training. Engagement rates for this trial should be interpreted with
caution. The volume of study-related outcome measures that
were extraneous to the intervention itself was high and might
have contributed to disengagement, particularly given that time
was reported as a barrier to app engagement even among those
who participated for the full duration of the study. Intervention Harms Medical students who actively trialed this intervention
reported both enjoyment and confidence with respect to these
activities while using the app. However, lower levels of
confidence and self-efficacy were reported with respect to
implementing the skills in real-world situations, with some
students not knowing when or how to apply specific skills and
others feeling “too overwhelmed” to do so. Previous research
has demonstrated that perceived self-efficacy can affect
engagement in digital health interventions [73]. Although stage
2 of the app was intended to strengthen and generalize skill
acquisition by providing access to targeted training in real-world
contexts, clearer guidance may have been required regarding
when and how to practice the skills. Future research may also
consider how to use in-app assessment of students’ confidence
and self-efficacy to tailor intervention delivery to their current
skill level and explore whether this enhances engagement. Medical students in this sample reported depression, anxiety,
and stress experiences at levels higher than those observed in
general population samples [66], and previous research indicates
that these factors can affect engagement in digital interventions
[73]. Furthermore, this sample reported high baseline
Psychological Inflexibility compared with a general population
sample [77]. Although the ACTraining app was intended to
improve this outcome, if existing inflexible behavioral
repertoires function as barriers to engagement, then steps would
need to be taken to mitigate this during the early stages of the
intervention. Future research should explore whether baseline
flexibility and inflexibility predict app engagement. We identified enjoyment of the intervention and its capacity to
hold medical students’ interest and attention as aspects of the
app requiring further attention. Most participants who trialed JMIR Form Res 2023 | vol. 7 | e43263 | p. 14
(page number not for citation purposes) XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al Limitations Furthermore, although subjective
feedback was informative regarding what was important to
participants while using the app, we were unable to confirm
whether these factors affected actual behavioral engagement
because of the sample size and study design, and further research
is required to explore the proposed relationships. Finally, the
low level of engagement with the stage 2 individualized skill
training component meant that most of the user experience data
collected pertained to the introductory module only. https://formative.jmir.org/2023/1/e43263 JMIR Form Res 2023 | vol. 7 | e43263 | p. 15
(page number not for citation purposes) Acknowledgments This research project was funded by the Centre for Rehab Innovations and the Priority Research Centre for Stroke and Brain
Injury at the University of Newcastle. The authors wish to acknowledge the Joint Medical Program (University of Newcastle and
University of New England) for supporting this research and the medical students who participated in the trial, the Cogniss team
for their commitment to fine-tuning the app throughout the development process, and Lucy Bailey for providing instrumental
support in the administrative aspects of the study. JMIR Form Res 2023 | vol. 7 | e43263 | p. 15
(page number not for citation purposes) XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al Data Availability The data sets generated and analyzed during this study are not publicly available for the protection of participant privacy, but
deidentified outcome data sets are available from the corresponding author upon reasonable request. Conflicts of Interest None declared. Multimedia Appendix 6 Learning experiences assessment. Learning experiences assessment. [DOCX File , 15 KB-Multimedia Appendix 6] g
p
[DOCX File , 15 KB-Multimedia Appendix 6] Multimedia Appendix 1 Stage 1 screenshot. Stage 1 screenshot. [PNG File , 395 KB-Multimedia Appendix 1] Stage 1 screenshot. [PNG File , 395 KB-Multimedia Appendix 1] Authors' Contributions ED wrote the manuscript, designed the study protocol, and created the app. ED and BK wrote and compiled the intervention
content. NH provided consultation on the study protocol design, data analyses, and app usability. GH led stakeholder engagement
and provided consultation on the translation of various aspects of the protocol and intervention to the cohort context. MN and
RW oversaw the project. All authors reviewed and contributed to the manuscript. Multimedia Appendix 5 Acceptability assessment and mean participant data at t1 (n=11). Acceptability assessment and mean participant d
[DOCX File , 24 KB-Multimedia Appendix 5] Multimedia Appendix 2 App home screen. [PNG File , 371 KB-Multimedia Appendix 2] References References
1. Yogeswaran V, El Morr C. Effectiveness of online mindfulness interventions on medical students' mental health: a systematic
review. BMC Public Health 2021 Dec 18;21(1):2293 [FREE Full text] [doi: 10.1186/s12889-021-12341-z] [Medline:
34920715]
2. Rotenstein LS, Ramos MA, Torre M, Segal JB, Peluso MJ, Guille C, et al. Prevalence of depression, depressive symptoms,
and suicidal ideation among medical students: a systematic review and meta-analysis. JAMA 2016 Dec 06;316(21):2214-2236
[FREE Full text] [doi: 10.1001/jama.2016.17324] [Medline: 27923088]
3. Seo C, Corrado M, Fournier K, Bailey T, Haykal KA. Addressing the physician burnout epidemic with resilience curricula
in medical education: a systematic review. BMC Med Educ 2021 Feb 01;21(1):80 [FREE Full text] [doi:
10.1186/s12909-021-02495-0] [Medline: 33526019]
4. Frajerman A, Morvan Y, Krebs MO, Gorwood P, Chaumette B. Burnout in medical students before residency: a systematic
review and meta-analysis. Eur Psychiatry 2019 Jan;55:36-42. [doi: 10.1016/j.eurpsy.2018.08.006] [Medline: 30384110]
5. Bugaj T, Cranz A, Junne F, Erschens R, Herzog W, Nikendei C. Psychosocial burden in medical students and specific
prevention strategies. Ment Health Prevent 2016 Mar;4(1):24-30. [doi: 10.1016/j.mhp.2015.12.003]
6. Fares J, Al Tabosh H, Saadeddin Z, El Mouhayyar C, Aridi H. Stress, burnout and coping strategies in preclinical medical
students. N Am J Med Sci 2016 Feb;8(2):75-81 [FREE Full text] [doi: 10.4103/1947-2714.177299] [Medline: 27042604]
JMIR Form Res 2023 | vol. 7 | e43263 | p. 16
https://formative.jmir.org/2023/1/e43263
(page number not for citation purposes)
FO 1. Yogeswaran V, El Morr C. Effectiveness of online mindfulness interventions on medical students' mental health: a systematic
review. BMC Public Health 2021 Dec 18;21(1):2293 [FREE Full text] [doi: 10.1186/s12889-021-12341-z] [Medline:
34920715] 1. Yogeswaran V, El Morr C. Effectiveness of online mindfulness interventions on medical students' mental health: a systematic
review. BMC Public Health 2021 Dec 18;21(1):2293 [FREE Full text] [doi: 10.1186/s12889-021-12341-z] [Medline:
34920715] 2. Rotenstein LS, Ramos MA, Torre M, Segal JB, Peluso MJ, Guille C, et al. Prevalence of depression, depressive symptoms,
and suicidal ideation among medical students: a systematic review and meta-analysis. JAMA 2016 Dec 06;316(21):2214-2236
[FREE Full text] [doi: 10.1001/jama.2016.17324] [Medline: 27923088] 3. Seo C, Corrado M, Fournier K, Bailey T, Haykal KA. Addressing the physician burnout epidemic with resilience curricula
in medical education: a systematic review. BMC Med Educ 2021 Feb 01;21(1):80 [FREE Full text] [doi:
10.1186/s12909-021-02495-0] [Medline: 33526019] ] [
]
4. Frajerman A, Morvan Y, Krebs MO, Gorwood P, Chaumette B. Burnout in medical students before residency: a systematic
review and meta-analysis. Multimedia Appendix 3 App screening questions. [PNG File , 433 KB-Multimedia Appendix 3] References Eur Psychiatry 2019 Jan;55:36-42. [doi: 10.1016/j.eurpsy.2018.08.006] [Medline: 30384110]
5. Bugaj T, Cranz A, Junne F, Erschens R, Herzog W, Nikendei C. Psychosocial burden in medical students and specific
prevention strategies. Ment Health Prevent 2016 Mar;4(1):24-30. [doi: 10.1016/j.mhp.2015.12.003] 5. Bugaj T, Cranz A, Junne F, Erschens R, Herzog W, Nikendei C. Psychosocial burden in medical students and specific
prevention strategies. Ment Health Prevent 2016 Mar;4(1):24-30. [doi: 10.1016/j.mhp.2015.12.003]
6. Fares J, Al Tabosh H, Saadeddin Z, El Mouhayyar C, Aridi H. Stress, burnout and coping strategies in preclinical medical JMIR Form Res 2023 | vol. 7 | e43263 | p. 16
(page number not for citation purposes) https://formative.jmir.org/2023/1/e43263 JMIR FORMATIVE RESEARCH Ditton et al 7. Maslach C, Leiter MP. Understanding the burnout experience: recent research and its implications for psychiatry. World
Psychiatry 2016 Jun;15(2):103-111 [FREE Full text] [doi: 10.1002/wps.20311] [Medline: 27265691]
8. Shanafelt TD, Boone S, Tan L, Dyrbye LN, Sotile W, Satele D, et al. Burnout and satisfaction with work-life balance among
US physicians relative to the general US population. Arch Intern Med 2012 Oct 08;172(18):1377-1385. [doi: 7. Maslach C, Leiter MP. Understanding the burnout experience: recent research and its implications for psychiatry. World
Psychiatry 2016 Jun;15(2):103-111 [FREE Full text] [doi: 10 1002/wps 20311] [Medline: 27265691] 8. Shanafelt TD, Boone S, Tan L, Dyrbye LN, Sotile W, Satele D, et al. Burnout and satisfaction with work-life balance among
US physicians relative to the general US population. Arch Intern Med 2012 Oct 08;172(18):1377-1385. [doi:
10.1001/archinternmed.2012.3199] [Medline: 22911330] 9. Shanafelt TD, Mungo M, Schmitgen J, Storz KA, Reeves D, Hayes SN, et al. Longitudinal study evaluating the association
between physician burnout and changes in professional work effort. Mayo Clin Proc 2016 Apr;91(4):422-431. [doi:
10.1016/j.mayocp.2016.02.001] [Medline: 27046522] 10. Kemp S, Hu W, Bishop J, Forrest K, Hudson JN, Wilson I, et al. Medical student wellbeing - a consensus statement from
Australia and New Zealand. BMC Med Educ 2019 Mar 04;19(1):69 [FREE Full text] [doi: 10.1186/s12909-019-1505-2]
[Medline: 30832630] 11. Walsh AL, Lehmann S, Zabinski J, Truskey M, Purvis T, Gould NF, et al. Interventions to prevent and reduce burnout
among undergraduate and graduate medical education trainees: a systematic review. Acad Psychiatry 2019 Aug;43(4):386-395. [doi: 10.1007/s40596-019-01023-z] [Medline: 30710229] 12. Harvey SB, Epstein RM, Glozier N, Petrie K, Strudwick J, Gayed A, et al. Mental illness and suicide among physicians. Lancet 2021 Sep 04;398(10303):920-930 [FREE Full text] [doi: 10.1016/S0140-6736(21)01596-8] [Medline: 34481571] 13. References Dyrbye LN, Satele D, West CP. Association of characteristics of the learning environment and US medical student burnout,
empathy, and career regret. JAMA Netw Open 2021 Aug 02;4(8):e2119110 [FREE Full text] [doi:
10.1001/jamanetworkopen.2021.19110] [Medline: 34369990] j
p
14. Amanullah S, Ramesh Shankar R. The impact of COVID-19 on physician burnout globally: a revie
2020 Oct 22;8(4):421 [FREE Full text] [doi: 10.3390/healthcare8040421] [Medline: 33105757] 15. Ishak W, Nikravesh R, Lederer S, Perry R, Ogunyemi D, Bernstein C. Burnout in medical students: a systematic review. Clin Teach 2013 Aug;10(4):242-245 [doi: 10 1111/tct 12014] [Medline: 23834570] 15. Ishak W, Nikravesh R, Lederer S, Perry R, Ogunyemi D, Bernstein C. Burnout in medical students
Clin Teach 2013 Aug;10(4):242-245. [doi: 10.1111/tct.12014] [Medline: 23834570] 16. Arif NM, Roslan NS, Ismail SB, Nayak RD, Jamian MR, Mohamad Ali Roshidi AS, et al. Prevalence and associated factors
of psychological distress and burnout among medical students: findings from two campuses. Int J Environ Res Public Health
2021 Aug 10;18(16):8446 [FREE Full text] [doi: 10.3390/ijerph18168446] [Medline: 34444193] 17. Wersebe H, Lieb R, Meyer AH, Hofer P, Gloster AT. The link between stress, well-being, and psychological flexibility
during an Acceptance and Commitment Therapy self-help intervention. Int J Clin Health Psychol 2018;18(1):60-68 [FREE
Full text] [doi: 10.1016/j.ijchp.2017.09.002] [Medline: 30487911] 18. Puolakanaho A, Tolvanen A, Kinnunen SM, Lappalainen R. A psychological flexibility -based intervention for burnout:a
randomized controlled trial. J Contextual Behav Sci 2020 Jan;15:52-67. [doi: 10.1016/j.jcbs.2019.11.007] 18. Puolakanaho A, Tolvanen A, Kinnunen SM, Lappalainen R. A psychological flexibility -based intervention for burnout:a
randomized controlled trial. J Contextual Behav Sci 2020 Jan;15:52-67. [doi: 10.1016/j.jcbs.2019.11.007] randomized controlled trial. J Contextual Behav Sci 2020 Jan;15:52-67. [doi: 10.1016/j.jcbs.2019.11.007]
19. Keyes CL. Mental illness and/or mental health? Investigating axioms of the complete state model of health. J Consult Clin
Psychol 2005 Jun;73(3):539-548 [FREE Full text] [doi: 10.1037/0022-006X.73.3.539] [Medline: 15982151]
20. Lamers SM, Westerhof GJ, Bohlmeijer ET, ten Klooster PM, Keyes CL. Evaluating the psychometric properties of the
Mental Health Continuum-Short Form (MHC-SF). J Clin Psychol 2011 Jan;67(1):99-110. [doi: 10.1002/jclp.20741]
[Medline: 20973032] ;
[
j j
]
19. Keyes CL. Mental illness and/or mental health? Investigating axioms of the complete state model of health. J Consult Clin
Psychol 2005 Jun;73(3):539-548 [FREE Full text] [doi: 10.1037/0022-006X.73.3.539] [Medline: 15982151]
20. Lamers SM, Westerhof GJ, Bohlmeijer ET, ten Klooster PM, Keyes CL. Evaluating the psychometric properties of the 19. Keyes CL. Mental illness and/or mental health? References Investigating axioms of the complete state model of health. J Consult Clin
Psychol 2005 Jun;73(3):539-548 [FREE Full text] [doi: 10.1037/0022-006X.73.3.539] [Medline: 15982151] y
;
( )
[
] [
] [
]
20. Lamers SM, Westerhof GJ, Bohlmeijer ET, ten Klooster PM, Keyes CL. Evaluating the psychometric properties of the
Mental Health Continuum-Short Form (MHC-SF). J Clin Psychol 2011 Jan;67(1):99-110. [doi: 10.1002/jclp.20741]
[Medline: 20973032] 20. Lamers SM, Westerhof GJ, Bohlmeijer ET, ten Klooster PM, Keyes CL. Evaluating the psychometric properties of the
Mental Health Continuum-Short Form (MHC-SF). J Clin Psychol 2011 Jan;67(1):99-110. [doi: 10.1002/jclp.20741]
[Medline: 20973032] 21. Lenoir AL, De Troyer C, Demoulin C, Gillain I, Bayot M. Challenges in treating physician burnout: the psychologist's
perspective. Presse Méd 2021 Jun;2:100006. [doi: 10.1016/j.lpmope.2021.100006] 21. Lenoir AL, De Troyer C, Demoulin C, Gillain I, Bayot M. Challenges in treating physician burnout: the psychologist's
perspective. Presse Méd 2021 Jun;2:100006. [doi: 10.1016/j.lpmope.2021.100006] 22. Taylor M, Hageman JR, Brown M. A mindfulness intervention for residents: relevance for pediatricians. Pediatr Ann 2016
Oct 01;45(10):e373-e376. [doi: 10.3928/19382359-20160912-01] [Medline: 27735974] 22. Taylor M, Hageman JR, Brown M. A mindfulness intervention for residents: relevance for pediatricians. Pediatr Ann 2016
Oct 01;45(10):e373-e376. [doi: 10.3928/19382359-20160912-01] [Medline: 27735974]
23
Wen L Sweeney TE Welton L Trockel M Katznelson L Encouraging mindfulness in medical house staff via smartphone 23. Wen L, Sweeney TE, Welton L, Trockel M, Katznelson L. Encouraging mindfulness in medical hou
app: a pilot study. Acad Psychiatry 2017 Oct;41(5):646-650. [doi: 10.1007/s40596-017-0768-3] [M pp
p
y
y
y
24. Awasthi S, Kaur A, Solanki H, Pamei G, Bhatt M. Smartphone use and the quality of life of medical students in the Kumaun
Region, Uttarakhand. J Family Med Prim Care 2020 Aug;9(8):4252-4258 [FREE Full text] [doi:
10.4103/jfmpc.jfmpc_805_20] [Medline: 33110841] 24. Awasthi S, Kaur A, Solanki H, Pamei G, Bhatt M. Smartphone use and the quality of life of medical students in the Kumaun
Region, Uttarakhand. J Family Med Prim Care 2020 Aug;9(8):4252-4258 [FREE Full text] [doi:
10.4103/jfmpc.jfmpc_805_20] [Medline: 33110841] 25. Singh K, Sarkar S, Gaur U, Gupta S, Adams OP, Sa B, et al. Smartphones and educational apps use among medical students
of a smart university campus. Front Commun 2021 Nov 2;6:49102. [doi: 10.3389/fcomm.2021.649102] 25. Singh K, Sarkar S, Gaur U, Gupta S, Adams OP, Sa B, et al. Smartphones and educational apps use among medical students
of a smart university campus. Front Commun 2021 Nov 2;6:49102. [doi: 10.3389/fcomm.2021.649102]
26. References Patel S, Akhtar A, Malins S, Wright N, Rowley E, Young E, et al. The acceptability and usability of digital health interventions 25. Singh K, Sarkar S, Gaur U, Gupta S, Adams OP, Sa B, et al. Smartphones and educational apps use among medical students
of a smart university campus. Front Commun 2021 Nov 2;6:49102. [doi: 10.3389/fcomm.2021.649102] 26. Patel S, Akhtar A, Malins S, Wright N, Rowley E, Young E, et al. The acceptability and usability of digital health interventions
for adults with depression, anxiety, and somatoform disorders: qualitative systematic review and meta-synthesis. J Med
Internet Res 2020 Jul 06;22(7):e16228 [FREE Full text] [doi: 10.2196/16228] [Medline: 32628116] 26. Patel S, Akhtar A, Malins S, Wright N, Rowley E, Young E, et al. The acceptability and usability of digital health interventions
for adults with depression, anxiety, and somatoform disorders: qualitative systematic review and meta-synthesis. J Med
Internet Res 2020 Jul 06;22(7):e16228 [FREE Full text] [doi: 10.2196/16228] [Medline: 32628116] 27. Levin ME, Haeger J, Cruz RA. Tailoring acceptance and commitment therapy skill coaching in the moment through
smartphones: results from a randomized controlled trial. Mindfulness 2018 Jul 21;10(4):689-699. [doi:
10.1007/s12671-018-1004-2] 27. Levin ME, Haeger J, Cruz RA. Tailoring acceptance and commitment therapy skill coaching in the moment through
smartphones: results from a randomized controlled trial. Mindfulness 2018 Jul 21;10(4):689-699. [doi:
10.1007/s12671-018-1004-2] Ditton et al Psychological flexibility as a malleable public health target: evidence from a representative
sample. J Contextual Behav Sci 2017 Apr;6(2):166-171. [doi: 10.1016/j.jcbs.2017.02.003] p
p
j j
42. Kinnunen SM, Puolakanaho A, Mäkikangas A, Tolvanen A, Lappalainen R. Does a mindfulness-, acceptance-, and
value-based intervention for burnout have long-term effects on different levels of subjective well-being? Int J Stress Manag
2020 Feb;27(1):82-87. [doi: 10.1037/str0000132] 42. Kinnunen SM, Puolakanaho A, Mäkikangas A, Tolvanen A, Lappalainen R. Does a mindfulness-, acceptance-, and
value-based intervention for burnout have long-term effects on different levels of subjective well-being? Int J Stress Manag
2020 Feb;27(1):82-87. [doi: 10.1037/str0000132] 43. Hayes SC, Strosahl KD, Wilson KG. Acceptance and Commitment Therapy: The Process and Practice of Mindful Change. 2nd edition. New York, NY, USA: The Guilford Press; 2016. 43. Hayes SC, Strosahl KD, Wilson KG. Acceptance and Commitment Therapy: The Process and Practice of Mindful Change. 2nd edition. New York, NY, USA: The Guilford Press; 2016. 44. Stabbe OK, Rolffs JL, Rogge RD. Flexibly and/or inflexibly embracing life: identifying fundamental approaches to life
with latent profile analyses on the dimensions of the Hexaflex model. J Contextual Behav Sci 2019 Apr;12:106-118. [doi:
10.1016/j.jcbs.2019.03.003] 44. Stabbe OK, Rolffs JL, Rogge RD. Flexibly and/or inflexibly embracing life: identifying fundamental approaches to life
with latent profile analyses on the dimensions of the Hexaflex model. J Contextual Behav Sci 2019 Apr;12:106-118. [doi:
10.1016/j.jcbs.2019.03.003] j j
45. Moran DJ. ACT for leadership: using acceptance and commitment training to develop crisis-resilient change managers. Int
J Behav Consult Ther 2010;6(4):341-355. [doi: 10.1037/h0100915] 45. Moran DJ. ACT for leadership: using acceptance and commitment training to develop crisis-resilient change managers. Int
J Behav Consult Ther 2010;6(4):341-355. [doi: 10.1037/h0100915] 46. Ramaci T, Bellini D, Presti G, Santisi G. Psychological flexibility and mindfulness as predictors of individual outcomes
in hospital health workers. Front Psychol 2019 Jun 12;10:1302 [FREE Full text] [doi: 10.3389/fpsyg.2019.01302] [Medline:
31249541] 46. Ramaci T, Bellini D, Presti G, Santisi G. Psychological flexibility and mindfulness as predictors of individual outcomes
in hospital health workers. Front Psychol 2019 Jun 12;10:1302 [FREE Full text] [doi: 10.3389/fpsyg.2019.01302] [Medline:
31249541] ]
47. Thompson G, McBride RB, Hosford CC, Halaas G. Resilience among medical students: the role of coping style and social
support. Teach Learn Med 2016;28(2):174-182. [doi: 10.1080/10401334.2016.1146611] [Medline: 27064719] 47. Thompson G, McBride RB, Hosford CC, Halaas G. Resilience among medical students: the role of coping style and social
support. Teach Learn Med 2016;28(2):174-182. Ditton et al [doi: 10.1080/10401334.2016.1146611] [Medline: 27064719] 48. Kroska EB, Calarge C, O’Hara MW, Deumic E, Dindo L. Burnout and depression in medical students: relations with
avoidance and disengagement. J Contextual Behav Sci 2017 Oct;6(4):404-408. [doi: 10.1016/j.jcbs.2017.08.003] 48. Kroska EB, Calarge C, O’Hara MW, Deumic E, Dindo L. Burnout and depression in medical students: relations with
avoidance and disengagement. J Contextual Behav Sci 2017 Oct;6(4):404-408. [doi: 10.1016/j.jcbs.2017.08.003] 48. Kroska EB, Calarge C, O’Hara MW, Deumic E, Dindo L. Burnout and depression in medical students: relations with
avoidance and disengagement. J Contextual Behav Sci 2017 Oct;6(4):404-408. [doi: 10.1016/j.jcbs.2017.08.003]
49. Johns G, Waddington L, Samuel V. Prevalence and predictors of mental health outcomes in UK doctors and final year
di
l
d
d
i
h COVID 19
d
i
J Aff
Di
d 2022 A
15 311 267 275 [FREE F ll
] [d i 48. Kroska EB, Calarge C, O’Hara MW, Deumic E, Dindo L. Burnout and depression in medical students: relations with
avoidance and disengagement. J Contextual Behav Sci 2017 Oct;6(4):404-408. [doi: 10.1016/j.jcbs.2017.08.003]
49. Johns G, Waddington L, Samuel V. Prevalence and predictors of mental health outcomes in UK doctors and final year
medical students during the COVID-19 pandemic. J Affect Disord 2022 Aug 15;311:267-275 [FREE Full text] [doi:
10.1016/j.jad.2022.05.024] [Medline: 35569608] g g
( )
j j
49. Johns G, Waddington L, Samuel V. Prevalence and predictors of mental health outcomes in UK doctors and final year
medical students during the COVID-19 pandemic. J Affect Disord 2022 Aug 15;311:267-275 [FREE Full text] [doi:
10.1016/j.jad.2022.05.024] [Medline: 35569608] 49. Johns G, Waddington L, Samuel V. Prevalence and predictors of mental health outcomes in UK doctors and final year
medical students during the COVID-19 pandemic. J Affect Disord 2022 Aug 15;311:267-275 [FREE Full text] [doi:
10.1016/j.jad.2022.05.024] [Medline: 35569608] j j
50. Palladino CL, Ange B, Richardson DS, Casillas R, Decker M, Gillies RA, et al. Measuring psychological flexibility in
medical students and residents: a psychometric analysis. Med Educ Online 2013 Aug 13;18:20932 [FREE Full text] [doi:
10.3402/meo.v18i0.20932] [Medline: 23948496] 50. Palladino CL, Ange B, Richardson DS, Casillas R, Decker M, Gillies RA, et al. Measuring psychological flexibility in
medical students and residents: a psychometric analysis. Med Educ Online 2013 Aug 13;18:20932 [FREE Full text] [doi:
10.3402/meo.v18i0.20932] [Medline: 23948496] 51. Szarko AJ, Houmanfar RA, Smith GS, Jacobs NN, Smith BM, Assemi K, et al. Ditton et al Clin Epidemiol 2018 Jan 18;10:153-157 [FREE Full text] [doi: 10.2147/CLEP.S146397] [Medline:
29403314] ]
36. Onwezen MC, van Veldhoven MJ, Biron M. The role of psychological flexibility in the demands–exhaustion–performance
relationship. Eur J Work Organ Psychol 2014;23(2):163-176. [doi: 10.1080/1359432x.2012.742242] 36. Onwezen MC, van Veldhoven MJ, Biron M. The role of psychological flexibility in the demands–exhaustion–performance
relationship. Eur J Work Organ Psychol 2014;23(2):163-176. [doi: 10.1080/1359432x.2012.742242] 37. Lloyd J, Bond FW, Flaxman PE. The value of psychological flexibility: examining psychological mechanisms underpinning
a cognitive behavioural therapy intervention for burnout. Work Stress 2013 Apr;27(2):181-199. [doi:
10.1080/02678373.2013.782157] 37. Lloyd J, Bond FW, Flaxman PE. The value of psychological flexibility: examining psychological mechanisms underpinning
a cognitive behavioural therapy intervention for burnout. Work Stress 2013 Apr;27(2):181-199. [doi:
10.1080/02678373.2013.782157] 38. Vilardaga R, Luoma JB, Hayes SC, Pistorello J, Levin ME, Hildebrandt MJ, et al. Burnout among the addiction counseling
workforce: the differential roles of mindfulness and values-based processes and work-site factors. J Subst Abuse Treat
2011 Jun;40(4):323-335 [FREE Full text] [doi: 10.1016/j.jsat.2010.11.015] [Medline: 21257281] 38. Vilardaga R, Luoma JB, Hayes SC, Pistorello J, Levin ME, Hildebrandt MJ, et al. Burnout among the addiction counseling
workforce: the differential roles of mindfulness and values-based processes and work-site factors. J Subst Abuse Treat
2011 Jun;40(4):323-335 [FREE Full text] [doi: 10.1016/j.jsat.2010.11.015] [Medline: 21257281] ( )
j j
39. Veage S, Ciarrochi J, Deane FP, Andresen R, Oades LG, Crowe TP. Value congruence, importance and success and in the
workplace: links with well-being and burnout amongst mental health practitioners. J Contextual Behav Sci 2014
Oct;3(4):258-264. [doi: 10.1016/j.jcbs.2014.06.004] 39. Veage S, Ciarrochi J, Deane FP, Andresen R, Oades LG, Crowe TP. Value congruence, importance and success and in the
workplace: links with well-being and burnout amongst mental health practitioners. J Contextual Behav Sci 2014
Oct;3(4):258-264. [doi: 10.1016/j.jcbs.2014.06.004] j j
40. Bond FW, Bunce D. The role of acceptance and job control in mental health, job satisfaction, and work performance. J
Appl Psychol 2003 Dec;88(6):1057-1067. [doi: 10.1037/0021-9010.88.6.1057] [Medline: 14640816] 40. Bond FW, Bunce D. The role of acceptance and job control in mental health, job satisfaction, and work performance. J
Appl Psychol 2003 Dec;88(6):1057-1067. [doi: 10.1037/0021-9010.88.6.1057] [Medline: 14640816] 41. Gloster AT, Meyer AH, Lieb R. Psychological flexibility as a malleable public health target: evidence from a representative
sample. J Contextual Behav Sci 2017 Apr;6(2):166-171. [doi: 10.1016/j.jcbs.2017.02.003] 41. Gloster AT, Meyer AH, Lieb R. Ditton et al 30. Baumel A, Muench F, Edan S, Kane JM. Objective user engagement with mental health apps: systematic search and
panel-based usage analysis. J Med Internet Res 2019 Sep 25;21(9):e14567 [FREE Full text] [doi: 10.2196/14567] [Medline:
31573916] 30. Baumel A, Muench F, Edan S, Kane JM. Objective user engagement with mental health apps: systematic search and
panel-based usage analysis. J Med Internet Res 2019 Sep 25;21(9):e14567 [FREE Full text] [doi: 10.2196/14567] [Medline:
31573916] ]
31. Sekhon M, Cartwright M, Francis JJ. Acceptability of healthcare interventions: an overview of reviews and development
of a theoretical framework. BMC Health Serv Res 2017 Jan 26;17(1):88 [FREE Full text] [doi: 10.1186/s12913-017-2031-8]
[Medline: 28126032] 31. Sekhon M, Cartwright M, Francis JJ. Acceptability of healthcare interventions: an overview of reviews and development
of a theoretical framework. BMC Health Serv Res 2017 Jan 26;17(1):88 [FREE Full text] [doi: 10.1186/s12913-017-2031-8]
[Medline: 28126032] [
]
32. Blatch-Jones AJ, Pek W, Kirkpatrick E, Ashton-Key M. Role of feasibility and pilot studies in randomised controlled trials:
a cross-sectional study. BMJ Open 2018 Sep 25;8(9):e022233 [FREE Full text] [doi: 10.1136/bmjopen-2018-022233]
[Medline: 30257847] 32. Blatch-Jones AJ, Pek W, Kirkpatrick E, Ashton-Key M. Role of feasibility and pilot studies in randomised controlled trials:
a cross-sectional study. BMJ Open 2018 Sep 25;8(9):e022233 [FREE Full text] [doi: 10.1136/bmjopen-2018-022233]
[Medline: 30257847] 33. Yogeswaran V, El Morr C. Mental Health for Medical Students, what do we know today? Proc Comput Sci 2022;198:307-310
[FREE Full text] [doi: 10.1016/j.procs.2021.12.245] 33. Yogeswaran V, El Morr C. Mental Health for Medical Students, what do we know today? Proc Comput Sci 2022;198:307-310
[FREE Full text] [doi: 10.1016/j.procs.2021.12.245] 34. Thabane L, Ma J, Chu R, Cheng J, Ismaila A, Rios LP, et al. A tutorial on pilot studies: the what, why and how. BMC Med
Res Methodol 2010 Jan 06;10:1 [FREE Full text] [doi: 10.1186/1471-2288-10-1] [Medline: 20053272] 34. Thabane L, Ma J, Chu R, Cheng J, Ismaila A, Rios LP, et al. A tutorial on pilot studies: the what, why and how. BMC Med
Res Methodol 2010 Jan 06;10:1 [FREE Full text] [doi: 10.1186/1471-2288-10-1] [Medline: 20053272] 35. Bell ML, Whitehead AL, Julious SA. Guidance for using pilot studies to inform the design of intervention trials with
continuous outcomes. Clin Epidemiol 2018 Jan 18;10:153-157 [FREE Full text] [doi: 10.2147/CLEP.S146397] [Medline:
29403314] 35. Bell ML, Whitehead AL, Julious SA. Guidance for using pilot studies to inform the design of intervention trials with
continuous outcomes. 10.1007/s12671-018-1004-2] 28. Amanullah S, McNally K, Zelin J, Cole J, Cernovsky Z. Are burnout prevention programs for hospital physicians needed? Asian J Psychiatr 2017 Apr;26:66-69. [doi: 10.1016/j.ajp.2017.01.009] [Medline: 28483095] 28. Amanullah S, McNally K, Zelin J, Cole J, Cernovsky Z. Are burnout prevention programs for hospital physicians needed? Asian J Psychiatr 2017 Apr;26:66-69. [doi: 10.1016/j.ajp.2017.01.009] [Medline: 28483095] 29. Kalani SD, Azadfallah P, Oreyzi H, Adibi P. Interventions for physician burnout: a systematic review of systematic reviews. Int J Prev Med 2018 Sep 17;9:81 [FREE Full text] [doi: 10.4103/ijpvm.IJPVM_255_18] [Medline: 30283613] 29. Kalani SD, Azadfallah P, Oreyzi H, Adibi P. Interventions for physician burnout: a systematic review of systematic reviews. Int J Prev Med 2018 Sep 17;9:81 [FREE Full text] [doi: 10.4103/ijpvm.IJPVM_255_18] [Medline: 30283613] JMIR Form Res 2023 | vol. 7 | e43263 | p. 17
(page number not for citation purposes) https://formative.jmir.org/2023/1/e43263 XSL•FO
RenderX JMIR FORMATIVE RESEARCH Ditton et al 52. Shahsavari Googhari Z, Hafezi F, Asgari P, Heidari A. The effectiveness of mindfulness-based cognitive therapy and
acceptance and commitment therapy on medical science students’subjective well-being, psychological distress, and emotion
regulation. J Shahrekord Univ Med Sci 2022 Jan 26;24(1):35-41. [doi: 10.34172/jsums.2022.07] 52. Shahsavari Googhari Z, Hafezi F, Asgari P, Heidari A. The effectiveness of mindfulness-based cognitive therapy and
acceptance and commitment therapy on medical science students’subjective well-being, psychological distress, and emotion
regulation. J Shahrekord Univ Med Sci 2022 Jan 26;24(1):35-41. [doi: 10.34172/jsums.2022.07] 52. Shahsavari Googhari Z, Hafezi F, Asgari P, Heidari A. The effectiveness of mindfulness-based cognitive therapy and
acceptance and commitment therapy on medical science students’subjective well-being, psychological distress, and emotion
regulation. J Shahrekord Univ Med Sci 2022 Jan 26;24(1):35-41. [doi: 10.34172/jsums.2022.07] g
( )
j
53. Villatte JL, Vilardaga R, Villatte M, Plumb Vilardaga JC, Atkins DC, Hayes SC. Acceptance and Commitment Therapy
modules: differential impact on treatment processes and outcomes. Behav Res Ther 2016 Feb;77:52-61 [FREE Full text]
[doi: 10.1016/j.brat.2015.12.001] [Medline: 26716932] g
j
53. Villatte JL, Vilardaga R, Villatte M, Plumb Vilardaga JC, Atkins DC, Hayes SC. Acceptance and Commitment Therapy
modules: differential impact on treatment processes and outcomes. Behav Res Ther 2016 Feb;77:52-61 [FREE Full text]
[doi: 10.1016/j.brat.2015.12.001] [Medline: 26716932] g
j
53. Villatte JL, Vilardaga R, Villatte M, Plumb Vilardaga JC, Atkins DC, Hayes SC. Acceptance and Commitment Therapy
modules: differential impact on treatment processes and outcomes. Behav Res Ther 2016 Feb;77:52-61 [FREE Full text]
[doi: 10.1016/j.brat.2015.12.001] [Medline: 26716932] j
54. Rolffs JL, Rogge RD, Wilson KG. Disentangling components of flexibility via the hexaflex model: development and
validation of the multidimensional psychological flexibility inventory (MPFI). Assessment 2018 Jun;25(4):458-482. [doi:
10.1177/1073191116645905] [Medline: 27152011] 54. Rolffs JL, Rogge RD, Wilson KG. Disentangling components of flexibility via the hexaflex model: development and
validation of the multidimensional psychological flexibility inventory (MPFI). Assessment 2018 Jun;25(4):458-482. [doi:
10.1177/1073191116645905] [Medline: 27152011] 54. Rolffs JL, Rogge RD, Wilson KG. Disentangling components of flexibility via the hexaflex model: development and
validation of the multidimensional psychological flexibility inventory (MPFI). Assessment 2018 Jun;25(4):458-482. [doi:
10.1177/1073191116645905] [Medline: 27152011] 55. Rogge RD, Daks JS, Dubler BA, Saint KJ. It's all about the process: examining the convergent validity, conceptual coverage,
unique predictive validity, and clinical utility of ACT process measures. J Contextual Behav Sci 2019 Oct;14:90-102. [doi:
10.1016/j.jcbs.2019.10.001] 55. Rogge RD, Daks JS, Dubler BA, Saint KJ. Ditton et al It's all about the process: examining the convergent validity, conceptual coverage,
unique predictive validity, and clinical utility of ACT process measures. J Contextual Behav Sci 2019 Oct;14:90-102. [doi:
10.1016/j.jcbs.2019.10.001] j j
56. Reeve A, Tickle A, Moghaddam N. Are acceptance and commitment therapy-based interventions effective for reducing
burnout in direct-care staff? A systematic review and meta-analysis. Ment Health Rev J 2018 Jul 04;23(3):131-155. [doi:
10.1108/mhrj-11-2017-0052] 56. Reeve A, Tickle A, Moghaddam N. Are acceptance and commitment therapy-based interventions effective for reducing
burnout in direct-care staff? A systematic review and meta-analysis. Ment Health Rev J 2018 Jul 04;23(3):131-155. [doi:
10.1108/mhrj-11-2017-0052] 57. Ditton E, Knott B, Hodyl N, Horton G, Walker FR, Nilsson M. Assessing the efficacy of an individualized psychological
flexibility skills training intervention app for medical student burnout and well-being: protocol for a randomized controlled
trial. JMIR Res Protoc 2022 Feb 04;11(2):e32992 [FREE Full text] [doi: 10.2196/32992] [Medline: 35119378] 58. Larmar S, Wiatrowski S, Lewis-Driver S. Acceptance and Commitment Therapy: an overview of techniques and applications. J Serv Sci Manag 2014 Jun;07(03):216-221. [doi: 10.4236/jssm.2014.73019] 59. Viskovich S, Pakenham KI. Pilot evaluation of a web-based acceptance and commitment therapy program to promote
mental health skills in university students. J Clin Psychol 2018 Dec;74(12):2047-2069. [doi: 10.1002/jclp.22656] [Medline:
29962090] ]
60. Firestone J, Cardaciotto L, Levin ME, Goldbacher E, Vernig P, Gambrel LE. A web-based self-guided program to promote
valued-living in college students: a pilot study. J Contextual Behav Sci 2019 Apr;12:29-38. [doi: 10.1016/j.jcbs.2019.01.004] 61. Schaufeli WB, Martínez IM, Pinto AM, Salanova M, Bakker AB. Burnout and engagement in university students: a
cross-national study. J Cross Cult Psychol 2002 Sep;33(5):464-481. [doi: 10.1177/0022022102033005003] 62. Maslach C, Jackson SE, Leiter MP. Maslach Burnout Inventory Manual. 3rd edition. Mountain View, CA, USA: CPP
Incorporated; 1996. 63. Obregon M, Luo J, Shelton J, Blevins T, MacDowell M. Assessment of burnout in medical students using the Maslach
Burnout Inventory-Student Survey: a cross-sectional data analysis. BMC Med Educ 2020 Oct 21;20(1):376 [FREE Full
text] [doi: 10.1186/s12909-020-02274-3] [Medline: 33087080] 64. Keyes CL. Brief description of the mental health continuum short form (MHC-SF). The University of North Carolina. Chapel Hill, NC, USA: The University of North Carolina; 2009. URL: https://peplab.web.unc.edu/wp-content/uploads/
sites/18901/2018/11/MHC-SFoverview.pdf [accessed 2021-01-30] 65. Seidler D, Stone B, Clark BE, Koran J, Drake CE. Evaluating the factor structure of the Multidimensional Psychological
Flexibility Inventory: an independent replication and extension. J Contextual Behav Sci 2020 Jul;17:23-31. [doi:
10.1016/j.jcbs.2020.04.007] 66. Ditton et al Impact of Acceptance and Commitment
Training on psychological flexibility and burnout in medical education. J Contextual Behav Sci 2022 Jan;23:190-199. [doi:
10.1016/j.jcbs.2022.02.004] 51. Szarko AJ, Houmanfar RA, Smith GS, Jacobs NN, Smith BM, Assemi K, et al. Impact of Acceptance and Commitment
Training on psychological flexibility and burnout in medical education. J Contextual Behav Sci 2022 Jan;23:190-199. [doi:
10.1016/j.jcbs.2022.02.004] 51. Szarko AJ, Houmanfar RA, Smith GS, Jacobs NN, Smith BM, Assemi K, et al. Impact of Acceptance and Commitment
Training on psychological flexibility and burnout in medical education. J Contextual Behav Sci 2022 Jan;23:190-199. [doi:
10.1016/j.jcbs.2022.02.004] JMIR Form Res 2023 | vol. 7 | e43263 | p. 18
(page number not for citation purposes) https://formative.jmir.org/2023/1/e43263 JMIR FORMATIVE RESEARCH JMIR Form Res 2023 | vol. 7 | e43263 | p. 19
(page number not for citation purposes) Ditton et al Front Psychol 2021 May 7;12:632134 [FREE Full text] [doi: 10.3389/fpsyg.2021.632134]
[Medline: 34025506] 80. Kroska EB, Roche AI, O'Hara MW. How much is enough in brief Acceptance and Commitment Th
trial. J Contextual Behav Sci 2020 Jan;15:235-244. [doi: 10.1016/j.jcbs.2020.01.009] j j
81. Towey-Swift KD, Lauvrud C, Whittington R. Acceptance and commitment therapy (ACT) for professional staff burnout:
a systematic review and narrative synthesis of controlled trials. J Ment Health (forthcoming) 2022 Feb 02:1-13. [doi:
10.1080/09638237.2021.2022628] [Medline: 35105253] 81. Towey-Swift KD, Lauvrud C, Whittington R. Acceptance and commitment therapy (ACT) for professional staff burnout:
a systematic review and narrative synthesis of controlled trials. J Ment Health (forthcoming) 2022 Feb 02:1-13. [doi:
10.1080/09638237.2021.2022628] [Medline: 35105253] 82. Pakenham KI, Landi G, Boccolini G, Furlani A, Grandi S, Tossani E. The moderating roles of psychological flexibility
and inflexibility on the mental health impacts of COVID-19 pandemic and lockdown in Italy. J Contextual Behav Sci 2020
Jul;17:109-118 [FREE Full text] [doi: 10.1016/j.jcbs.2020.07.003] [Medline: 32834969] 82. Pakenham KI, Landi G, Boccolini G, Furlani A, Grandi S, Tossani E. The moderating roles of psychological flexibility
and inflexibility on the mental health impacts of COVID-19 pandemic and lockdown in Italy. J Contextual Behav Sci 2020
Jul;17:109-118 [FREE Full text] [doi: 10.1016/j.jcbs.2020.07.003] [Medline: 32834969] Ditton et al Lovibond SH, Lovibond PF. Manual for the Depression Anxiety Stress Scales. 2nd edition. Sydney, Australia: Psychology
Foundation of Australia; 1995. 67. Henry JD, Crawford JR. The short-form version of the Depression Anxiety Stress Scales (DASS-21): construct validity
and normative data in a large non-clinical sample. Br J Clin Psychol 2005 Jun;44(Pt 2):227-239. [doi:
10.1348/014466505X29657] [Medline: 16004657] 68. Bangor A, Kortum P, Miller J. Determining what individual SUS scores mean: adding an adjective rating scale. J Usability
Stud 2009 May;4(3):114-123. 69. Bangor A, Kortum PT, Miller JT. An empirical evaluation of the system usability scale. Int J Human Comput Interact 2008
Jul 30;24(6):574-594. [doi: 10.1080/10447310802205776] 70. Kinnunen SM, Puolakanaho A, Tolvanen A, Mäkikangas A, Lappalainen R. Does mindfulness-, acceptance-, and value-based
intervention alleviate burnout?—A person-centered approach. Int J Stress Manag 2019 Feb;26(1):89-101. [doi:
10.1037/str0000095] 71. Lewis JR. The system usability scale: past, present, and future. Int J Human Comput Interact 2018 Mar 30;34(7):577-590. [doi: 10.1080/10447318.2018.1455307] 72. Brooke J. SUS: a 'quick and dirty' usability scale. In: Jordan PW, Thomas B, McClelland L, Weerdmeester B, editors. Usability Evaluation in Industry. London, UK: CRC Press; 1996:189-194. 73. Perski O, Blandford A, West R, Michie S. Conceptualising engagement with digital behaviour change interventions: a
systematic review using principles from critical interpretive synthesis. Transl Behav Med 2017 Jun;7(2):254-267 [FREE
Full text] [doi: 10.1007/s13142-016-0453-1] [Medline: 27966189] JMIR Form Res 2023 | vol. 7 | e43263 | p. 19
(page number not for citation purposes) https://formative.jmir.org/2023/1/e43263 JMIR FORMATIVE RESEARCH Ditton et al 74. Prochaska JJ, Vogel EA, Chieng A, Kendra M, Baiocchi M, Pajarito S, et al. A therapeutic relational agent for reducing
problematic substance use (Woebot): development and usability study. J Med Internet Res 2021 Mar 23;23(3):e24850
[FREE Full text] [doi: 10.2196/24850] [Medline: 33755028]
75. The Jamovi Project. Jamovi (Version 2.3). Jamovi. 2022. URL: https://www.jamovi.org/ [accessed 2022-12-08]
76. Michalec B, Keyes CL. A multidimensional perspective of the mental health of preclinical medical students. Psychol Health
Med 2013;18(1):89-97. [doi: 10.1080/13548506.2012.687825] [Medline: 22676432]
77. Grégoire S, Gagnon J, Lachance L, Shankland R, Dionne F, Kotsou I, et al. Validation of the english and french versions
of the multidimensional psychological flexibility inventory short form (MPFI-24). J Contextual Behav Sci 2020
Oct;18:99-110. [doi: 10.1016/j.jcbs.2020.06.004]
78. Wang J, Song B, Shao Y, Zhu J. Effect of online psychological intervention on burnout in medical residents from different
majors: an exploratory study. Ditton et al Front Psychol 2021 May 7;12:632134 [FREE Full text] [doi: 10.3389/fpsyg.2021.632134]
[Medline: 34025506]
79. Dindo L. One-day acceptance and commitment training workshops in medical populations. Curr Opin Psychol 2015 Apr
01;2:38-42 [FREE Full text] [doi: 10.1016/j.copsyc.2015.01.018] [Medline: 25793217]
80. Kroska EB, Roche AI, O'Hara MW. How much is enough in brief Acceptance and Commitment Therapy? A randomized
trial. J Contextual Behav Sci 2020 Jan;15:235-244. [doi: 10.1016/j.jcbs.2020.01.009]
81. Towey-Swift KD, Lauvrud C, Whittington R. Acceptance and commitment therapy (ACT) for professional staff burnout:
a systematic review and narrative synthesis of controlled trials. J Ment Health (forthcoming) 2022 Feb 02:1-13. [doi:
10.1080/09638237.2021.2022628] [Medline: 35105253]
82. Pakenham KI, Landi G, Boccolini G, Furlani A, Grandi S, Tossani E. The moderating roles of psychological flexibility
and inflexibility on the mental health impacts of COVID-19 pandemic and lockdown in Italy. J Contextual Behav Sci 2020
Jul;17:109-118 [FREE Full text] [doi: 10.1016/j.jcbs.2020.07.003] [Medline: 32834969] 74. Prochaska JJ, Vogel EA, Chieng A, Kendra M, Baiocchi M, Pajarito S, et al. A therapeutic relational agent for reducing
problematic substance use (Woebot): development and usability study. J Med Internet Res 2021 Mar 23;23(3):e24850
[FREE Full text] [doi: 10.2196/24850] [Medline: 33755028] j
p
j
g
76. Michalec B, Keyes CL. A multidimensional perspective of the mental health of preclinical medical students. Psychol Health
Med 2013;18(1):89-97. [doi: 10.1080/13548506.2012.687825] [Medline: 22676432] j
p
j
g
76. Michalec B, Keyes CL. A multidimensional perspective of the mental health of preclinical medical students. Psychol Health
Med 2013;18(1):89-97. [doi: 10.1080/13548506.2012.687825] [Medline: 22676432] 77. Grégoire S, Gagnon J, Lachance L, Shankland R, Dionne F, Kotsou I, et al. Validation of the english and french versions
of the multidimensional psychological flexibility inventory short form (MPFI-24). J Contextual Behav Sci 2020
Oct;18:99-110. [doi: 10.1016/j.jcbs.2020.06.004] 77. Grégoire S, Gagnon J, Lachance L, Shankland R, Dionne F, Kotsou I, et al. Validation of the english and french versions
of the multidimensional psychological flexibility inventory short form (MPFI-24). J Contextual Behav Sci 2020
Oct;18:99-110. [doi: 10.1016/j.jcbs.2020.06.004] j j
78. Wang J, Song B, Shao Y, Zhu J. Effect of online psychological intervention on burnout in medical residents from different
majors: an exploratory study. Front Psychol 2021 May 7;12:632134 [FREE Full text] [doi: 10.3389/fpsyg.2021.632134]
[Medline: 34025506] 78. Wang J, Song B, Shao Y, Zhu J. Effect of online psychological intervention on burnout in medical residents from different
majors: an exploratory study. Abbreviations ACTraining: Acceptance and Commitment Training
REDCap: Research Electronic Data Capture
SUS: System Usability Scale
TFA: theoretical framework of acceptability received 22.11.22; accepted 28.11.22; published 10.01.23
Please cite as:
Ditton E, Knott B, Hodyl N, Horton G, Walker FR, Nilsson M
Medical Student Experiences of Engaging in a Psychological Flexibility Skill Training App for Burnout and Well-being: Pilot Feasibility
Study
JMIR Form Res 2023;7:e43263
URL: https://formative.jmir.org/2023/1/e43263
doi: 10.2196/43263
PMID: ©Elizabeth Ditton, Brendon Knott, Nicolette Hodyl, Graeme Horton, Frederick Rohan Walker, Michael Nilsson. Originally
published in JMIR Formative Research (https://formative.jmir.org), 10.01.2023. This is an open-access article distributed under
the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted
use, distribution, and reproduction in any medium, provided the original work, first published in JMIR Formative Research, is
properly cited. The complete bibliographic information, a link to the original publication on https://formative.jmir.org, as well
as this copyright and license information must be included. JMIR Form Res 2023 | vol. 7 | e43263 | p. 20
(page number not for citation purposes) https://formative.jmir.org/2023/1/e43263 https://formative.jmir.org/2023/1/e43263 XSL•FO
RenderX XSL•FO
RenderX
|
https://openalex.org/W2753745143
|
https://ora.ox.ac.uk/objects/uuid:fe0615a1-4d37-4352-93c8-16971653161a/files/m807103ebe712301d42f4a84bc3f3b298
|
English
| null |
Complete genome sequence of the nematicidal Bacillus thuringiensis MYBT18247
|
Journal of biotechnology
| 2,017
|
cc-by
| 8,590
|
Abstract Bacillus thuringiensis is a rod-shaped facultative anaerobic spore forming bacterium of the genus Bacillus. The defining
feature of the species is the ability to produce parasporal crystal inclusion bodies, consisting of δ-endotoxins, encoded
by cry-genes. Here we present the complete annotated genome sequence of the nematicidal B. thuringiensis strain
MYBT18246. The genome comprises one 5,867,749 bp chromosome and 11 plasmids which vary in size from 6330 bp to
150,790 bp. The chromosome contains 6092 protein-coding and 150 RNA genes, including 36 rRNA genes. The plasmids
encode 997 proteins and 4 t-RNA’s. Analysis of the genome revealed a large number of mobile elements involved in
genome plasticity including 11 plasmids and 16 chromosomal prophages. Three different nematicidal toxin genes were
identified and classified according to the Cry toxin naming committee as cry13Aa2, cry13Ba1, and cry13Ab1. Strikingly, these
genes are located on the chromosome in close proximity to three separate prophages. Moreover, four putative toxin genes
of different toxin classes were identified on the plasmids p120510 (Vip-like toxin), p120416 (Cry-like toxin) and p109822 (two
Bin-like toxins). A comparative genome analysis of B. thuringiensis MYBT18246 with three closely related B. thuringiensis
strains enabled determination of the pan-genome of B. thuringiensis MYBT18246, revealing a large number of singletons,
mostly represented by phage genes, morons and cryptic genes. rds: Bacillus thuringiensis, Bacillus cereus sensu lato, Prophages, Parasporal crystal protein, Pan-Core-genom and can be subdivided into three different homology
groups. In total, over 787 different Cry toxins have been
identified, each exhibiting toxicity against a specific host
organism [14]. It has been shown that B. thuringiensis
strains can produce more than one Cry toxin resulting
in a broad host range. As such, B. thuringiensis has been
used widely as a biopesticide in agriculture for several
decades [1, 2, 8, 13, 15, 16]. Bacillus thuringiensis is a
member of the genus Bacillus, which are low GC-con-
tent, Gram-positive bacteria with a respiratory metabol-
ism and the ability to form heat- and desiccation-resistant
endospores [11, 17, 18]. Within this genus, B. thuringiensis
is a member of the Bacillus cereus sensu lato species
group which originally contained seven different species
(B. cereus, B. anthracis, B. thuringiensis, B. mycoides, B. pseudomycoides, B. weihenstephanensis, B. cytotoxicus
[17–25]). Historically, most pathogenic and phenotypic
properties were used for strain classification. However, re-
cent publications utilizing genomic criteria suggest that
the species group should be extended by species B. toyo-
nensis [26, 27]. * Correspondence: hlieseg@gwdg.de
1Department of Genomic and Applied Microbiology & Göttingen Genomics
Laboratory, Institute of Microbiology and Genetics, University of Göttingen,
Göttingen, Germany
Full list of author information is available at the end of the article © The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Abstract Moreover, the three proposed species Complete Genome sequence of the
nematicidal Bacillus thuringiensis MYBT18246 Jacqueline Hollensteiner1, Anja Poehlein1, Cathrin Spröer2, Boyke Bunk2, Anna E. Sheppard3,4, Philip Rosentstiel5,
Hinrich Schulenburg4 and Heiko Liesegang1* Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48
DOI 10.1186/s40793-017-0259-x Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48
DOI 10.1186/s40793-017-0259-x Open Access Introduction
ll
h Bacillus thuringiensis is an ubiquitously distributed,
rod-shaped, Gram-positive, spore forming, facultative
anaerobic bacterium [1, 2]. Bacillus thuringiensis has
been isolated from various ecological niches, including
soil, aquatic habitats, phylloplane and insects [3–7]. The
defining property of the species is the ability to produce
parasporal protein crystals consisting of δ-endotoxins,
which are predominantly encoded on plasmids [1, 8, 9]. These proteins are toxic towards a wide spectrum of
invertebrates of the orders Lepidoptera, Diptera, Coleop-
tera, Hymenoptera, Homoptera, Orthoptera, Mallophaga
and other species like Gastropoda, mites, protozoa and
especially nematodes [7, 10–12]. In addition, B. thurin-
giensis produce additional toxins such as Cyt, Vip, and
Sip toxins [13]. Cry toxins represent the largest group * Correspondence: hlieseg@gwdg.de
1Department of Genomic and Applied Microbiology & Göttingen Genomics
Laboratory, Institute of Microbiology and Genetics, University of Göttingen,
Göttingen, Germany
Full list of author information is available at the end of the article Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48 Page 2 of 10 Page 2 of 10 Page 2 of 10 “Bacillus gaemokensis”[28], “Bacillus manliponensis”[29]
and “Bacillus bingmayongensis” [30] have been isolated
and effectively published. However, these names had not
yet appeared on a Validation List at the time of pulbication
[31]. Due to the very close phylogenetic relationships, it
has also been proposed to assign the eleven species to a
single extended Bcsl species [32, 33]. The genome of Bcsl-
members contains a highly conserved chromosome with
regard to gene content, sequence similarity and genome
synteny, while variation can be observed within mobile
genomic elements such as prophages, insertion elements,
transposons, and plasmids [34]. Due to the significance of
Bcsl group members in human health, the food industry
and agriculture, resolving the phylogeny is of great im-
portance. Because of the highly conserved 16S rRNA-
genes, the classical 16S phylogeny of Bcsl strains is incon-
clusive. Thus, a combination of 16S and a seven gene
multi-locus sequence typing scheme have been used to es-
tablish taxonomic relationships within species of the Bcsl-
group [35, 36]. Comparative genomics of the cry-gene loci
has revealed remarkable proximity to elements of gen-
ome plasticity such as plasmids, transposons, inser-
tion elements and prophages [2, 37–39]. The activity
of these mobile elements has resulted in a magnitude of
highly diverse plasmid sizes through rearrangements such
as deletions and insertions, as well as migration of cry-
genes into the bacterial chromosome [40]. Organism information
Classification and features Bacillus thuringiensis belongs to the genus Bacillus and
has been isolated in the end of the nineteenth century
[17, 20] and used as a biocontrol agent for several
decades
[7,
18,
21]. The
strain
B. thuringiensis
MYBT18246 is a Gram-positive, rod-shaped and spore
forming bacterium (Fig.1a), as most B. thuringiensis [7]. Bacillus thuringiensis MYBT18246 was isolated in the
Schulenburg lab by AS from a mixture of genotypes
present in the strain NRRL B-18246, originally provided
by the Agricultural Research Service Patent Culture
Collection (United States Department of Agriculture,
Peoria, IL, USA) [43–45]. As a member of the species B. thuringiensis, B. thuringiensis MYBT18246 is facultative
anaerobe, motile and is able to produce parasporal
crystal toxins, which is the characteristic feature of this
species [2]. Growth occurred at temperatures ranging
from 10 to 48 °C and optimal growth was monitored at
mesophil temperatures ranging from 28 to 37 °C [46]. The pH range of B. thuringiensis strains varies from
pH 4.9 to 8.0, with the optimum documented as pH 7
[47, 48]. Strain B. thuringiensis MYBT18246 exhibits flat,
opaque colonies with undulate, curled margins and
produced crystals during the stationary phase (Fig. 1a-b). Characteristic features of B. thuringiensis MYBT18246
are listed in Table 1. Introduction
ll
h The worldwide
distribution of B. thuringiensis and its capacity to adapt to
a diverse spectrum of invertebrate hosts is explained by
the formation of spores and a remarkable variability in
crystal protein families [13]. This toxin arsenal, especially
the copy number of individual toxin genes, can be shaped
by reciprocal co-adaptation with a nematode host, as pre-
viously demonstrated using controlled evolution experi-
ments in the laboratory [41, 42]. The B. thuringiensis
strain MYBT18246 described herein and its host Caenor-
habditis elegans have been selected as a model system for
such co-evolution experiments [41]. One aim of this se-
quencing project was to provide a high-quality reference
genome
sequence
for
the
original
B. thuringiensis MYBT18246 in order to obtain a detailed phylogeny and
shed light on the evolution of this microparasite, with
a particular focus on the presence of virulence factors,
elements of genome plasticity and host adaptation fac-
tors. Here we present the genome of the nematicidal
B. thuringiensis MYBT18246 and its comparative ana-
lysis to the three closest relatives identified by MLST
phylogeny. Extended feature descriptions The cell size of Bacillus thuringiensis can vary from
0.5 × 1.2 μm - 2.5 × 10 μm [11]. Categorization into the Fig. 1 Microscopic characteristics of Bacillus thuringiensis MYBT18246. a Light microscope analysis of Gram stained B. thuringiensis MYBT18246 cells
(40×). b Phase contrast microscope analysis of sporulated and Cry-toxin producing cells of B. thuringiensis MYBT18246 (40×) Fig. 1 Microscopic characteristics of Bacillus thuringiensis MYBT18246. a Light microscope analysis of Gram stained B. thuringiensis MYBT18246 cells
(40×). b Phase contrast microscope analysis of sporulated and Cry-toxin producing cells of B. thuringiensis MYBT18246 (40×) Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48 Page 3 of 10 Page 3 of 10 Table 1 Classification and general features of B. thuringiensis
MYBT18246 [54]
MIGS ID
Property
Term
Evidence codea
Classification
Domain Bacteria
TAS [86]
Phylum Firmicutes
TAS [47]
Class Bacilli
TAS [87, 88]
Order Bacillales
TAS [18, 89]
Family Bacillaceae
TAS [18, 90]
Genus Bacillus
TAS [17, 18]
Species Bacillus
thuringiensis
TAS [46]
Strain MYBT18246
IDA
Gram stain
positive
IDA
Cell shape
rod-shaped
IDA
Motility
Motile
TAS [46]
Sporulation
Spore-forming
IDA
Temperature range
10–48 °C
TAS [46]
Optimum
temperature
28–37 °C
TAS [46]
pH range; Optimum
4.9–8.0; 7.0
TAS [47, 48]
Carbon source
Organic carbon
source
NAS
MIGS-6
Habitat
Worldwide
TAS [7]
MIGS-6.3 Salinity
Salt tolerant
TAS [7]
MIGS-22
Oxygen requirement Aerobic, facultative
anaerobic
TAS [11]
MIGS-15
Biotic relationship
Free-living, microparasite
of C. elegans
TAS [41]
MIGS-14
Pathogenicity
Nematode pathogen
TAS [41]
MIGS-4
Geographic location
not reported
MIGS-5
Sample collection
not reported
MIGS-4.1 Latitude
unreported
MIGS-4.2 Longitude
unreported
MIGS-4.4 Altitude
unreported
aEvidence codes - IDA: Inferred from Direct Assay; TAS: Traceable Author
Statement (i.e., a direct report exists in the literature); NAS: Non-traceable Author
Statement (i.e., not directly observed for the living, isolated sample, but based on
a generally accepted property for the species, or anecdotal evidence). These evidence
codes are from the Gene Ontology project Table 1 Classification and general features of B. thuringiensis species were chosen for phylogenetic analysis using multi-
locus sequence typing as previously developed by Priest
[36] (Fig. 2b). Bacillus subtilis subsp. subtilis str. 168 was
selected as an outgroup to root the tree [17, 18]. The
phylogenies were generated using the Neighbor-Joining
method [50] and evolutionary distances were computed
by the Maximum Composite Likelihood method [51]. In
total, 217 MLST gene sequences were compared with
1000
bootstrap
replicates. Phylogenetic
analysis
was
conducted in MEGA7 [52]. Extended feature descriptions All used reference sequences
were retrieved from GenBank hosted at NCBI. Growth conditions and genomic DNA preparation Growth conditions and genomic DNA preparation
Genomic
DNA
was
isolated
from
B. thuringiensis
MYBT18246 using the DNeasy blood and tissue kit
(Qiagen, Hilden, Germany) for 454 pyrosequencing [55]
and
the
Genomic-Tip
100/G
Kit
(Qiagen,
Hilden,
Germany) for Single Molecule real-time sequencing [56]
according to the manufacturer’s instructions. For SMRT-
sequencing the procedure and Checklist: Greater than
10 kb Template Preparation Using AmPure PB Beads
was used and blunt end ligation was applied overnight. Whole-genome sequencing was performed using a 454
GS-FLX system (Titanium GS70 chemistry; Roche Life
Science, Mannheim, Germany) and on one SMRT Cell
on the PacBio RSII system using P6-chemistry (Pacific
Biosciences, Menlo Park, CA, USA). aEvidence codes - IDA: Inferred from Direct Assay; TAS: Traceable Author
Statement (i.e., a direct report exists in the literature); NAS: Non-traceable Author
Statement (i.e., not directly observed for the living, isolated sample, but based on
a generally accepted property for the species, or anecdotal evidence). These evidence
codes are from the Gene Ontology project aEvidence codes - IDA: Inferred from Direct Assay; TAS: Traceable Author
Statement (i.e., a direct report exists in the literature); NAS: Non-traceable Author
Statement (i.e., not directly observed for the living, isolated sample, but based on
a generally accepted property for the species, or anecdotal evidence). These evidence
codes are from the Gene Ontology project group of Gram-positive organisms was confirmed by
Gram staining, as shown in Fig. 1a. In Fig. 1b the produc-
tion of Cry toxins can be observed. These toxins accumu-
late during the sporulation phase next to the endospore
and build phase-bright inclusions [7]. Bacillus thuringien-
sis MYBT18246 exhibited 99% 16S rRNA sequence
identity to other published Bcsl-members [49]. As a result
of the high sequence similarity, a phylogenetic differenti-
ation of B. thuringiensis MYBT18246 based on 16S
phylogenetic differentiation of Bcsl group members is
impossible (Fig. 2a). As an alternative, 23 B. thuringiensis
strains, and a representative of each of the Bcsl group Genome sequencing information
Genome project history p
j
y
Bacillus thuringiensis MYBT18246 was used in a co-
evolution study with a Caenorhabditis elegans host. The
original strain MYBT18246 was selected for sequencing
in order to generate a reliable reference sequence for
subsequent experiments [41, 42]. The genome sequence
was analyzed to identify virulence factors and fitness fac-
tors contributing to the efficient infection of C. elegans. Additionally, the phylogenetic position of B. thuringien-
sis MYBT18246 in the Bcsl group was determined [41]. The complete genome sequence has been deposited in
GenBank
with
the
accession
numbers
(CP015350-
CP015361) and in the integrated Microbial Genomes
database with the Taxon ID 2671180122 [53]. A sum-
mary of the project information and its association with
MIGS version 2.0 compliance [54] is shown in Table 2. Genome sequencing and assembly A summary of the project information can be found in
Table 2. 454-pyrosequencing was carried out at the
Institute of Clinical Molecular Biology in Kiel, Germany
and SMRT-sequencing at the DSMZ Braunschweig. First, approximately 331,000,454-reads with an average
length of 600 bp were assembled using the Newbler 2.8
de novo assembler (Roche Diagnostics), resulting in 729 Page 4 of 10 Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48 Fig. 2 Phylogenetic tree highlighting the taxonomic relation of B. thuringiensis MYBT18246 (red) based on a) 16rDNA amplicon within the Bacillus
clade b) Multi-locus sequence typing within the Bacillus cereus sensu lato species group. GenBank accession numbers are given in parentheses. Comparison includes strains of the Bacilli clade or Bcsl group members (blue). Paenibacillus larvae subsp. larvae DSM 25430 or Bacillus subtilis
subsp. subtilis str. 168 has been used as outlier to root the tree. Sequences were aligned using ClustalW 1.6 [91, 92]. The phylogenetic tree was
constructed by using the Neighbor-Joining method [50] and evolutionary distances were computed by the Maximum Composite Likelihood
method [51] within MEGA7.0 [52]. Numbers at the nodes are bootstrap values calculated from 1000 replicates Fig. 2 Phylogenetic tree highlighting the taxonomic relation of B. thuringiensis MYBT18246 (red) based on a) 16rDNA amplicon within the Bacillus
clade b) Multi-locus sequence typing within the Bacillus cereus sensu lato species group. GenBank accession numbers are given in parentheses. Comparison includes strains of the Bacilli clade or Bcsl group members (blue). Paenibacillus larvae subsp. larvae DSM 25430 or Bacillus subtilis
subsp. subtilis str. 168 has been used as outlier to root the tree. Sequences were aligned using ClustalW 1.6 [91, 92]. The phylogenetic tree was
constructed by using the Neighbor-Joining method [50] and evolutionary distances were computed by the Maximum Composite Likelihood
method [51] within MEGA7.0 [52]. Numbers at the nodes are bootstrap values calculated from 1000 replicates contigs with a coverage of 18 x. Repeats were resolved
and gaps between contigs were closed using PCR with
Sanger sequencing of the products with BigDye 3.0
chemistry
and
an
ABI3730XL
capillary
sequencer
(Applied Biosystems, Life Technology GmbH, Darm-
stadt, Germany). Manually editing in Gap4 (version
4.11) software of the Staden package [57] was performed
to improve the sequence quality. For final gap closure
PacBio sequencing was used. Genome sequencing and assembly A total of 27,870 PacBio
reads with a mean length of 14,053 bp were assembled
using HGAP 2.0 [58], resulting in a coverage of 50 x,
with further analysis using SMRT Portal (v2.3.0) [59]. Finally, both assemblies were combined, resulting in 12
contigs including a closed circular chromosome se-
quence of 5,867,749 bp. Eight additional contigs exhib-
ited overlapping ends and were circularized to plasmid
sequences ranging from 6.3 kb to 150 kb (Table 3). The
assembly was checked for coverage drop downs and
extremes of disparities including GC, AT, RY, and MK. Moreover, we determined the origin of replication of B. thuringiensis MYBT18246 by comparative analysis with
OriC of eight other B. thuringiensis strains available in
DoriC [60, 61]. These strains varied in chromosome size
from 5.2 Mb to 5.8 Mb but all shared a similar GC- Table 2 Project information
MIGS ID
Property
Term
MIGS 31
Finishing quality
Complete
MIGS-28
Libraries used
Two genomic libraries: 454
pyrosequencing shotgun
library, PacBio library
MIGS 29
Sequencing platforms
454 GS FLX system, PacBioRSII
MIGS 31.2
Fold coverage
18 × 454; 50 × PacBio
MIGS 30
Assemblers
Newbler 2.8; HGAP v2.3.0
MIGS 32
Gene calling method
Prodigal 2.6
Locus Tag
BT246
Genbank ID
CP015350-CP015361
GenBank Date of Release
2016–07-15
GOLD ID
Gp0020852
BIOPROJECT
PRJNA290307
MIGS 13
Source Material Identifier
Department of Evolutionary
Ecology and Genetics, CAU, Kiel
Project relevance
Evolution Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48 Page 5 of 10 content of 35%. In total, including B. thuringiensis
MYBT18246, two OriC regions were identified using the
ORF-Finder [62]. One region was highly conserved with
regard to OriC length (178/179 nt), OriC AT content
(~0.69) and number of DnaA boxes (4). The second
region varied in OriC length (564–767 nt) and OriC AT
content (~0.67–0.7), but all had the same number of
DnaA boxes (9). B. thuringiensis MYBT18246 showed
the highest OriC similarities with both OriC regions of
B. thuringiensis Bt407. Insights from the genome sequence Insights from the genome sequence
To
investigate
the
phylogeny
of
B. thuringiensis
MYBT18246 two approaches were used. First, nineteen
Bacillus strains were chosen for 16S rRNA analysis
within the Bacillus clade (Fig. 2a). The 16S rRNA
phylogeny shows that B. thuringiensis MYBT18246 clus-
ters with other Bcsl group members within the Bacillus
clade. However, the low bootstrap values confirm the
limitations of 16S rRNA as a discriminatory marker
within the Bcsl species group. Second, we applied an
MLST approach based on the scheme by Priest et al. [36]. This revealed that MYBT18246 clusters with the
toxin cured B. thuringiensis Bt407, insecticidal B. thurin-
giensis serovar chinensis CT-43, and with the nematicidal
B. thuringiensis YBT-1518 within the Bcsl phylogeny
(Fig. 2b). Based on this phylogeny and the phenotypic
defining feature of the B. thuringiensis species group
(the ability to produce crystal toxins against inverte-
brates
and
nematodes),
the
strain
B. thuringiensis
MYBT18246 can be safely classified as nematicidal B. thuringiensis. Genome annotation For a detailed analysis of encoded toxins in B. thurin-
giensis MYBT18246, we generated a local database
consisting of all available Cry, Cyt, Vip and Sip protein
sequences from UniProtKB [71] and GenBank [72]. The
database was curated to generate a set of non-redundant
reference toxins. In total, we identified three different Annotation was performed with Prokka v1.9 [63] using
the manually curated Bacillus thuringiensis strain Bt407
[64] as a species reference and a comprehensive toxin
protein database (including Cry, Cyt, Vip, and Sip
toxins) as feature references. The Prokka pipeline was
applied using prodigal for gene calling [65]. RNAmmer
1.2 [66] and Aragorn [67] were used for rRNA gene and
t-RNA identification, respectively. Additionally, signal
leader peptides were identified with SignalP 4.0 [68] and
non-coding RNAs with an Infernal 1.1 search against the
Rfam database [69]. Annotation of cry toxin genes were
manually
corrected
and
named
according
to
the
standards of the Cry toxin nomenclature by Crickmore
[70]. Identified toxins were deposited at the Bacillus
thuringiensis Toxin nomenclature database [14]. Table 4 Genome statistics
Attribute
Value
% of Total
Genome size (bp)
6,752,488
100
DNA coding (bp)
5,623,665
83.28
DNA G + C (bp)
2,389,665
35.39
DNA scaffolds
12
100
Total genes
7239
100
Protein coding genes
7089
97.9
RNA genes
151
2.09
Genes in internal clusters
2694
37.22
Genes with function prediction
5274
72.86
Genes assigned to COGs
4662
64.40
Genes with Pfam domains
5503
76.02
Genes with signal peptides
500
6.91
Genes with transmembrane helices
1863
25.74
CRISPR repeats
0
0 Genome sequencing and assembly Table 3 Summary of genome: one chromosome and 11 plasmids
Label
Size (Mb)
Topology
INSDC identifier
RefSeq ID
Chromosome
5.8
Circular
CP015350
NZ_CP015350.1
Plasmid 1
0.151
Circular
CP015351
NZ_CP015351.1
Plasmid 2
0.142
Circular
CP015352
NZ_CP015352.1
Plasmid 3
0.121
Circular
CP015353
NZ_CP015353.1
Plasmid 4
0.120
Circular
CP015354
NZ_CP015354.1
Plasmid 5
0.110
Circular
CP015355
NZ_CP015355.1
Plasmid 6
0.101
Circular
CP015356
NZ_CP015356.1
Plasmid 7
0.055
Linear
CP015357
NZ_CP015357.1
Plasmid 8
0.047
Circular
CP015358
NZ_CP015358.1
Plasmid 9
0.017
Linear
CP015359
NZ_CP015359.1
Plasmid 10
0.014
Linear
CP015360
NZ_CP015360.1
Plasmid 11
0.006
Circular
CP015361
NZ_CP015361.1 Table 3 Summary of genome: one chromosome and 11 plasmids
Label
Size (Mb)
Topology
INSDC identifier
RefSeq ID with assigned function and 1815 genes encoding proteins
with unknown function (Table 4). All gene products have
been assigned to COGs (Table 5). The genome sequence of
B. thuringiensis MYBT18246 is available in GenBank
(CP015350 for the chromosome and CP015351 - CP015361
for the plasmids). Genome properties The genome of B. thuringiensis MYBT18246 consists of
12 replicons with a circular chromosome of 5,867,749 bp
(Table 3). The GC content of the chromosome is 35% and
the GC content of the plasmids ranges from 32 to 37%. The total number of protein coding genes is 7089 with
6092 genes on the chromosome and 997 genes on the
plasmids. The
genome
harbors
12
rRNA
clusters,
111 t-RNA genes, 5274 predicted protein-coding genes Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48 Page 6 of 10 Page 6 of 10 Table 5 Number of protein encoding genes associated with
general COG functional categories
Code
Value
%
Description
J
226
3.19
Translation, ribosomal structure
and biogenesis
A
0
0
RNA processing and modification
K
487
6.87
Transcription
L
625
8.82
Replication, recombination
and repair
B
1
0.01
Chromatin structure and
dynamics
D
59
0.83
Cell cycle control, Cell division,
chromosome partitioning
V
141
1.99
Defense mechanisms
T
218
3.08
Signal transduction mechanisms
M
270
3.81
Cell wall/membrane biogenesis
N
64
0.90
Cell motility
U
79
1.12
Intracellular trafficking and
secretion
O
121
1.71
Posttranslational modification,
protein turnover, chaperones
C
214
3.02
Energy production and
conversion
G
263
3.71
Carbohydrate transport and
metabolism
E
420
5.93
Amino acid transport and
metabolism
F
128
1.81
Nucleotide transport and
metabolism
H
177
2.50
Coenzyme transport and
metabolism
I
129
1.82
Lipid transport and metabolism
P
243
3.43
Inorganic ion transport and
metabolism
Q
83
1.17
Secondary metabolites
biosynthesis, transport and
catabolism
R
653
9.22
General function prediction only
S
505
7.13
Function unknown
-
1978
27.9
Not in COGs
aThe total number is based on the total number of protein coding genes in
the genome InterPro [75] revealed a p120510 encoded putative Vip--
like toxin, a p120416 encoded putative Cry-like toxin
and two p109822 encoded putative Bin-like toxins with
potential for future studies. Additionally,
the
B. thuringiensis
MYBT18246
chromosome was screened for prophage regions by
using the Phage Search Tool with default parameters. PHAST identifies prophage regions based on key genes
from a reference database and defines the boundaries
using a genomic composition-based algorithm. For a
more detailed description see [76]. A total of 16 putative
prophage
loci
were
identified
in
the
chromosome,
including three that were associated with the previously
identified chromosomally encoded cry toxin genes. As
shown in Fig. Genome properties 3, the cry toxins (displayed in red, track 4)
are located in close proximity to identified prophage
regions (displayed in blue, track 3). Furthermore, all B. thuringiensis MYBT18246 extra-chromosomal elements
were also screened for prophages to check whether we
could identify phages that reside in a linear or circular
state in the host, as has been reported in 2013 by Fortier
et al. [77]. Apparently, intact phage regions were identi-
fied according to the PHAST score system on p150790,
p120416, p109822, p101287 and p46701. The finding of prophage associated cry genes in strain
MYBT18246 indicates that phages may serve as vectors
for the transmission of virulence factors within the spe-
cies B. thuringiensis. This resembles the previously
described lysogenic conversion of pathogens by phages
[78], supporting the idea that phages may represent a
driving force for the distribution of fitness factors as well
as virulence factors [78–80]. The finding that toxins,
which are generally specific for a certain type of host or-
ganism, are located within a mobile genomic element in
the chromosome of this bacterium, suggests that phages
of strain MYBT18246 may contribute to adaptation to
different hosts [81–83]. Extended insights The tracks
from the outside represent: (track 1–2) Genes encoded by the leading and lagging strand of B. thuringiensis MYBT18246 marked in COG colors [93]; (track
3) putative prophage regions, identified with PHAST in blue [76], (track 4) identified cry toxin genes in red; (track 5–7) orthologs for the genomes of B. thuringiensis YBT-1518 (CP005935.1), B. thuringiensis CT-43 (CP001907.1), B. thuringiensis Bt407 (CP003889.1) illustrated in red to light yellow, singletons in grey
(grey: <1e−20; light yellow: 1e−21–1e−50; gold: 1e−51–1e−90; light orange: 1e−91–1e−100; orange: 1e−101–1e−120; red: >1e−121 (track 7) % GC plot (track 8), GC
skew [(GC)/(G + C)]. Visualization was done with DNAPlotter [94] Fig. 3 Circular visualization of the genome comparison of B. thuringiensis MYBT18246 with 3 other sequenced B. thuringiensis strains. The tracks
from the outside represent: (track 1–2) Genes encoded by the leading and lagging strand of B. thuringiensis MYBT18246 marked in COG colors [93]; (track
3) putative prophage regions, identified with PHAST in blue [76], (track 4) identified cry toxin genes in red; (track 5–7) orthologs for the genomes of B. thuringiensis YBT-1518 (CP005935.1), B. thuringiensis CT-43 (CP001907.1), B. thuringiensis Bt407 (CP003889.1) illustrated in red to light yellow, singletons in grey
(grey: <1e−20; light yellow: 1e−21–1e−50; gold: 1e−51–1e−90; light orange: 1e−91–1e−100; orange: 1e−101–1e−120; red: >1e−121 (track 7) % GC plot (track 8), GC
skew [(GC)/(G + C)]. Visualization was done with DNAPlotter [94] more singletons than the compared genomes. This result
confirms the high degree of conservation of the four
Bacillus thuringiensis strains (Fig. 2a and b) and it also
refines the phylogenetic relationship of the strains to
each other based on non-orthologous regions. Singletons
are located on the chromosome as well as on extra-
chromosomal elements. The density of singletons is
higher (2.5 fold) on the plasmids. Notably, all major
chromosomal differences can be attributed to prophage
regions. All gene products were assigned to COG
categories and investigated for PFAM domains and Sig-
nal peptides (Table 6). In detail, those genes code for: (i)
phage proteins, (ii) morons (virulence factors), (iii) a vast
majority of proteins with cryptic function. This is sup-
ported by Fig. 3 which clearly shows that the regions of
differences (track 5–7) directly correspond to the regions
of identified phages (track 3). Moreover, the identified
cry toxins (track 4) are adjacent to identified prophage
regions and could be suggested as morons. Extended insights Based on the proximity within the tree (Fig. 2b), the
genomes of B. thuringiensis Bt407, B. thuringiensis sero-
var chinensis CT-43 and B. thuringiensis YBT-1518 were
identified as closest relatives and selected for an in depth
comparative analysis. Shared gene contents were deter-
mined, visualized and compared, with a focus on known
virulence factors such as cry toxins and pathogenic
driving forces such as phages. The analysis revealed
unique as well as shared gene contents for each strain
(Fig. 3). In Fig. 3 the outer rings represent the genes on
the leading and lagging strand with COG classification. The inner rings (track 5–7) illustrate the orthologous
genes of B. thuringiensis YBT-1518, B. thuringiensis CT-
43, B. thuringiensis Bt407 in red (high similarity) to light
yellow (low similarity), and white (no similarity). The aThe total number is based on the total number of protein coding genes in
the genome cry toxin genes in the B. thuringiensis MYBT18246
genome
and
classified
them
as
cry13Aa2
(>95%),
cry13Ba1 (<78%) and cry13Ab1 (<95%), based on the
similarity scheme from the Cry-toxin naming committee
by Crickmore [13, 70]. Notably, these cry toxin genes are
encoded
on
the
chromosome
and
not
on
extra-
chromosomal elements as has been previously reported
for the vast majority of cry toxin genes [7, 73, 74]. The
toxin gene analysis revealed four additional putative
toxin-like genes on plasmids with sequence similarity to
cry genes and vip genes. A Pfam domain analysis using Page 7 of 10 Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48 Fig. 3 Circular visualization of the genome comparison of B. thuringiensis MYBT18246 with 3 other sequenced B. thuringiensis strains. The tracks
from the outside represent: (track 1–2) Genes encoded by the leading and lagging strand of B. thuringiensis MYBT18246 marked in COG colors [93]; (track
3) putative prophage regions, identified with PHAST in blue [76], (track 4) identified cry toxin genes in red; (track 5–7) orthologs for the genomes of B. thuringiensis YBT-1518 (CP005935.1), B. thuringiensis CT-43 (CP001907.1), B. thuringiensis Bt407 (CP003889.1) illustrated in red to light yellow, singletons in grey
(grey: <1e−20; light yellow: 1e−21–1e−50; gold: 1e−51–1e−90; light orange: 1e−91–1e−100; orange: 1e−101–1e−120; red: >1e−121 (track 7) % GC plot (track 8), GC
skew [(GC)/(G + C)]. Visualization was done with DNAPlotter [94] Fig. 3 Circular visualization of the genome comparison of B. thuringiensis MYBT18246 with 3 other sequenced B. thuringiensis strains. Conclusion methyltransferase, type-restriction enzymes, sporulation,
resistance and genes involved in genetic competence
were identified. In particular, the finding of restriction-
modification systems indicates a protection mechanism
against other phages and plasmids and thus forms a
putative barrier against further genomic modification. In this work we present the whole-genome sequence of
B. thuringiensis MYBT18246 and its specific genome
features. The genome includes three nematicidal cry13
gene variants located on the chromosome, which were
named according to sequence similarity as stated by the
Cry
Toxin
Nomenclature
Committee,
as
cry13Aa2,
cry13Ba1, and cry13Ab1. Four additional putative toxin
genes were identified with low sequence similarity to
other known toxins on plasmids: p120510 (Vip-like
toxin), p120416 (Cry-like toxin) and p109822 (two Bin-
like toxins). These toxins contained complete toxin do-
mains, yet the activity against potential hosts should be
elucidated in future studies. The genome comprises a
large number of mobile elements involved in genome
plasticity including eleven plasmids and sixteen chromo-
somal prophages. Both plasmids and prophages are im-
portant HGT elements indicating that they are an
important driving force for the evolution of pathogens. The most striking finding is the close proximity of the
chromosomal nematicidal cry toxin genes to three
distinct prophages indicating a contribution of phages in
defining the host range of this strain. B. thuringiensis
MYBT18246 may show potential as a biocontrol agent
against nematodes which should be addressed in future
experiments. Table 6 General genome features of B. thuringiensis MYBT18246
and close relatives
Genome features
Genome name
B. thuringiensis
MYBT18246a
B. thuringiensis
407b
B. thuringiensis
YBT-1518c
B. thuringiensis
CT-43d
Sequencing
status
Finished
Finished
Finished
Finished
Genome
size (Mbp)
6.75
6.13
6.67
6.15
DNA coding
(bp)
5,623,665
5,133,026
5,421,574
5,079,667
GC (%)
35.4
35.02
35.29
35.12
DNA scaffolds
12
10
7
11
Total gene
count
7239
6442
6738
6252
Protein coding
genes (%)
97.9
95.9
98.0
95.1
RNA genes
151
180
139
124
Genes in
internal clusters
2694
489
370
334
Genes with
function prediction
5274
4615
5193
4211
Genes assigned to
COGs
4662
3634
3746
3505
Genes with Pfam
domains
5503
4991
5333
4809
Genes with signal
peptides
500
447
471
418
Genes with
transmembrane helices
1863
1750
1854
1698
CRISPR repeats
0
2
0
2
Accession numbers: aCP015350, bCP003889, cCP005935, dCP001907 Table 6 General genome features of B. thuringiensis MYBT18246
and close relatives Extended insights Venn diagram displays the
orthologous genes between B. thuringiensis MYBT18246 (CP015350-CP015361), B. thuringiensis YBT-1518 (CP005935-CP002486), B. thuringiensis
serovar chinensis CT-43 (CP001907-CP001917) and B. thuringiensis Bt407 (CP003889-CP003898). Ortholog detection was performed with Proteinortho
[84] including protein blast with a similarity cut-off of (50%) and an E-value of 1e−10. The total number of genes and paralogs are depicted under the
corresponding species name. Open reading frames that were classified as pseudogenes were not included in this analysis Abbreviation
B B
ll
B h B: Bacillus; B. thuringiensis: Bacillus thuringiensis; Bcsl: Bacillus cereus sensu lato;
Cry: Crystal; Cyt: Cytolytic; IMG: Integrated Microbial Genomes; MLST: Multi-locus
sequence typing; PHAST: Phage Search Tool; Sip: Secreted insecticidal protein;
SMRT: Single molecule real-time; Vip: Vegetative insectididal protein Extended insights Additionally,
the singletons were screened for further virulence factors
and
genes
encoding
type-IV secretion
system,
C5- circular representation of the chromosome comparison
revealed that prophages are a major source of regional
differences between the strains (Fig. 3). Additionally, the
pan-genome of B. thuringiensis MYBT18246 compared
to the three closest relatives was determined (Fig. 4). Orthologous genes between all four organisms were
identified
by
comparing
the
whole
genomes
using
Proteinortho [84] with a similarity cutoff of 50% and an
E-value of 1e−10. Gbk-files were downloaded from NCBI
and the protein sequences were extracted using cds_ex-
tractor v0.7.1 [85]. Detected paralogous genes are dis-
played in the Venn diagram in Fig. 4. All four strains
share a core genome of 4298 genes. This is equivalent to
67% of each genome. Bacillus thuringiensis MYBT18246
shares 4 additional genes exclusively with B. thuringien-
sis Bt407, 17 genes with B. thuringiensis serovar chinen-
sis CT-43 and 327 genes with B. thuringiensis YBT-1518. Bacillus thuringiensis serovar chinensis CT-43 and B. thuringiensis
Bt407
share
398
orthologous
genes. Notably, the genome of B. thuringiensis MYBT18246
contains 1242 orphan genes and thus two to threefold Page 8 of 10 Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48 Fig. 4 Venn diagram of the genome comparison of B. thuringiensis MYBT18246 with other B. thuringiensis strains. Venn diagram displays the
orthologous genes between B. thuringiensis MYBT18246 (CP015350-CP015361), B. thuringiensis YBT-1518 (CP005935-CP002486), B. thuringiensis
serovar chinensis CT-43 (CP001907-CP001917) and B. thuringiensis Bt407 (CP003889-CP003898). Ortholog detection was performed with Proteinortho
[84] including protein blast with a similarity cut-off of (50%) and an E-value of 1e−10. The total number of genes and paralogs are depicted under the
corresponding species name. Open reading frames that were classified as pseudogenes were not included in this analysis Fig. 4 Venn diagram of the genome comparison of B. thuringiensis MYBT18246 with other B. thuringiensis strains. Venn diagram displays the
orthologous genes between B. thuringiensis MYBT18246 (CP015350-CP015361), B. thuringiensis YBT-1518 (CP005935-CP002486), B. thuringiensis
serovar chinensis CT-43 (CP001907-CP001917) and B. thuringiensis Bt407 (CP003889-CP003898). Ortholog detection was performed with Proteinortho
[84] including protein blast with a similarity cut-off of (50%) and an E-value of 1e−10. The total number of genes and paralogs are depicted under the
corresponding species name. Open reading frames that were classified as pseudogenes were not included in this analysis Fig. 4 Venn diagram of the genome comparison of B. thuringiensis MYBT18246 with other B. thuringiensis strains. References 27. Oren A, Garrity GM. List of new names and new combinations previously
effectively, but not validly, published. Int J Syst Evol Microbiol. 2014;64:1–5. doi:10.1099/ijsem.0.000737. 1. Bechtel DB, Bulla LA, Kramer KJ, Bechtel DB, David- LI. Electron microscope
study of Sporulation and Parasporal crystal formation in Bacillus
thuringiensis. J Bacteriol. 1976;127:1472–81. 1. Bechtel DB, Bulla LA, Kramer KJ, Bechtel DB, David- LI. Electron microscope
study of Sporulation and Parasporal crystal formation in Bacillus
thuringiensis. J Bacteriol. 1976;127:1472–81. thuringiensis. J Bacteriol. 1976;127:1472–81. 28. Jung MY, Paek WK, Park IS, Han JR, Sin Y, Paek J, et al. Bacillus gaemokensis
sp. nov., isolated from foreshore tidal flat sediment from the Yellow Sea. J
Microbiol. 2010;48:867–71. 2. Ibrahim MA, Griko N, Junker M, Bulla LA. Bacillus thuringiensis: a genomics
and proteomics perspective. Bioeng Bugs. 2010;1:31–50. 3. Carozzi NB, Kramer VC, Warren G, Evola S, Koziel MG. Prediction of
insecticidal activity of Bacillus thuringiensis strains by polymerase chain
reaction product profiles. Appl Environ Microbiol. 1991;57:3057–61. 29. Jung MY, Kim JS, Paek WK, Lim J, Lee H, Kim PI, et al. Bacillus manliponensis
sp. nov., a new member of the Bacillus cereus group isolated from foreshore
tidal flat sediment. J Microbiol. 2011;49:1027–32. 29. Jung MY, Kim JS, Paek WK, Lim J, Lee H, Kim PI, et al. Bacillus manliponensis
sp. nov., a new member of the Bacillus cereus group isolated from foreshore
tidal flat sediment. J Microbiol. 2011;49:1027–32. 4. Iriarte J, Porcar M, Lecadet M-M, Caballero P. Isolation and characterization
of Bacillus thuringiensis strains from aquatic environments in Spain. Curr
Microbiol. 2000;40:402–8. 30. Liu B, Liu GH, Hu GP, Cetin S, Lin NQ, Tang JY, et al. Bacillus
bingmayongensis sp. nov., isolated from the pit soil of emperor Qin’s Terra-
cotta warriors in China. Antonie Van Leeuwenhoek. 2014;105:501–10. 30. Liu B, Liu GH, Hu GP, Cetin S, Lin NQ, Tang JY, et al. Bacillus
bingmayongensis sp. nov., isolated from the pit soil of emperor Qin’s Terra-
cotta warriors in China. Antonie Van Leeuwenhoek. 2014;105:501–10. 5. Smith RA, Couche GA. The phylloplane as a source of Bacillus thuringiensis
variants. Appl Environ Microbiol. 1991;57:311–5. 31. NL; Validation of the publication of new names and new combinations
previously effectively published outside the IJSB. List No. 65. Int J Syst
Bacteriol. 1998;48(Pt 2):627. 6. Burges D, Hurst JA. Ecology of Bacillus thuringiensis in storage moths. J
Invertebr Pathol. 1977;30:131–9. 32. Author details
1 24. Lechner S, Mayr R, Francis KP, Prüss BM, Kaplan T, Wießner-Gunkel E, et al. Bacillus weihenstephanensis sp. nov. is a new psychrotolerant species of the
Bacillus cereus group. Int J Syst Bacteriol. 1998;48:1373–82. doi:10.1099/
00207713-48-4-1373. 1Department of Genomic and Applied Microbiology & Göttingen Genomics
Laboratory, Institute of Microbiology and Genetics, University of Göttingen,
Göttingen, Germany. 2Leibniz Institute DSMZ-German Collection of
Microorganisms and Cell Cultures, Braunschweig, Germany. 3Present address:
Nuffield Department of Medicine, University of Oxford, Oxford, UK. 4Department of Evolutionary Ecology and Genetics, Zoological Institute,
Christian-Albrechts University of Kiel, Kiel, Germany. 5Institute of Clinical
Molecular Biology, Christian-Albrechts University of Kiel, Kiel, Germany. 25. Guinebretière MH, Auger S, Galleron N, Contzen M, de Sarrau B, de Buyser
ML, et al. Bacillus cytotoxicus sp. nov. is a novel thermotolerant species of
the Bacillus cereus group occasionally associated with food poisoning. Int J
Syst Evol Microbiol. 2013;63:31–40. y
y
Molecular Biology, Christian-Albrechts University of Kiel, Kiel, Germany. 26. Jiménez G, Urdiain M, Cifuentes A, López-López A, Blanch AR, Tamames J,
et al. Description of Bacillus toyonensis sp. nov., a novel species of the
Bacillus cereus group, and pairwise genome comparisons of the species of
the group by means of ANI calculations. Syst Appl Microbiol. 2013;36:383–91. doi:10.1016/j.syapm.2013.04.008. Received: 2 August 2016 Accepted: 8 August 2017 Received: 2 August 2016 Accepted: 8 August 2017 Received: 2 August 2016 Accepted: 8 August 2017 Authors’ contributions
HL
d HS d
i
d h HL and HS designed the study. AP supervised the genome analysis. JH
corrected the annotation, analyzed the genome with focus on comparative
genomics. JH, AP and HL wrote the manuscript. BB, CS and PR performed the
genome sequencing. HL performed the assembly and the annotation of the
sequence data. JH performed the microscopy of strain MYBT18246. AS and CS
isolated the genomic DNA. All authors read and approved the final manuscript 20. Frankland GC, Frankland PF. Studies on some New Micro-Organisms
obtained from Air. Philosophical Transactions of the Royal Society of
London. 1887. p. 257–87. 21. Ernst B. Ueber die Schlaffsucht der Mehlmottenraupe (Ephestia kuhniella)
und ihren Erreger Bacillus thuringiensis n. sp. Zeitschrift für Angew Entomol. 1915;2:21–56. Funding
h
k 16. Sanchis V, Bourguet D. Bacillus thuringiensis: applications in agriculture and
insect resistance management. A review Agron Sustain Dev. 2008;28:11–20. g
We thank the German Research Foundation (DFG-SPP1399, Grant LI 1690/2–1
to HL; SCHU 1415/9 to HS, and RO 2994/3 to PR) for financial support. We
acknowledge support by the German Research Foundation and the Open
Access Publication Funds of the Göttingen University. 17. Cohn F. Untersuchungen über Bakterien. Beiträge zur Biologie der Pflanzen. 1872;1:127–224. 18. Skerman V, McGowan V, Sneath P. Approved lists of bacterial names. Int J
Syst Bacteriol. 1980;30:225–420. 19. Scott E, Dyer DW. Divergence of the SigB regulon and pathogenesis of the
Bacillus cereus Sensu Lato group. BMC Genomics. 2012;13:564. doi:10.1186/
1471-2164-13-564. The authors declare that they have no competing interests. 23. Nakamura LK. Bacillus pseudomycoides sp. nov. Int J Syst Bacteriol. 1998;48:
1031–5. doi:10.1099/00207713-48-3-1031. Acknowledgements
h
k
h We thank Sascha Dietrich and Andreas Leimbach for bioinformatic support. We as well thank Nicole Heyer and Simone Severitt for excellent technical
assistance. Page 9 of 10 Page 9 of 10 Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48 References Helgason E, Okstad OA, Caugant DA, Johansen HA, Fouet A, Mock M, et al. Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis–one species on
the basis of genetic evidence. Appl Environ Microbiol. 2000;66:2627–30. 7. Schnepf E, Crickmore N, Van RJ, Lereclus D, Baum J, Feitelson J, et al. Bacillus
thuringiensis and its Pesticidal crystal proteins. Microbiol Mol Biol Rev. 1998;62:775–806. 33. Okinaka TR, Keim P, Okinaka RT, Keim P. The Phylogeny of Bacillus cereus
sensu lato. Microbiol Spectr. 2016;4 doi:10.1128/microbiolspec. 8. Sanahuja G, Banakar R, Twyman RM, Capell T, Christou P. Bacillus
thuringiensis: a century of research, development and commercial
applications. Plant Biotechnol J. 2011;9:283–300. 34. Rasko DA, Altherr MR, Han CS, Ravel J. Genomics of the Bacillus cereus
group of organisms. FEMS Microbiol Rev. 2005;29:303–29. 9. Vidal-Quist JC, Castañera P, González-Cabrera J. Diversity of Bacillus
thuringiensis strains isolated from citrus orchards in Spain and evaluation of
their insecticidal activity against Ceratitis Capitata. J Microbiol Biotechnol. 2009;19:749–59. 9. Vidal-Quist JC, Castañera P, González-Cabrera J. Diversity of Bacillus
thuringiensis strains isolated from citrus orchards in Spain and evaluation of
their insecticidal activity against Ceratitis Capitata. J Microbiol Biotechnol. 2009;19:749–59. 35. Schmidt TR, Scott EJ II, Dyer DW. Whole-genome phylogenies of the family
Bacillaceae and expansion of the sigma factor gene family in the Bacillus
cereus species-group. BMC Genomics. 2011;12:430. doi:10.1186/1471-2164-
12-430. 10. Feitelson J. The Bacillus thuringiensis family tree. In: Kim L, editor. Advanced
engineered pesticides. 1st ed. New York: CRC Press; 1993. p. 63–71. 36. Priest FG, Barker M, Baillie LWJ, Holmes EC, Maiden MCJ. Population structure
and evolution of the Bacillus cereus group. Society. 2004;186:7959–70. 11. De Vos P, Garrity GM, Jones D, Krieg NR, Ludwig W, Rainey FA, et al. Bergey’s manual of systematic bacteriology. In: Vos P, Garrity G, Jones D,
Krieg NR, Ludwig W, Rainey FA, Schleifer K-H, Whitman W, editors. Volume
3: the Firmicutes. 2nd ed. New York: Springer; 2009. p. 1–1317. 37. Yu H, Zhang J, Huang D, Gao J, Song F. Characterization of Bacillus
thuringiensis strain Bt185 toxic to the Asian cockchafer: Holotrichia parallela. Curr Microbiol. 2006;53:13–7. 38. Ackermann H-WW, Azizbekyan RR, Bernier RL, Barjac H, Saindoux S, Valero
JR, et al. Phage typing of Bacillus subtilis and B. thuringiensis. Res Microbiol. 1995;146:643–57. 12. Sabha ME-S, Adayel SA, El-Masry SA, Alazazy H. Bacillus thuringiensis (Bt)
toxin for the control of citrus trees snails. Researcher. 2013;5:26–32. 13. Competing interest 22. Flügge C. Die Mikroorganismen. 2.Auflage. Leipzig, Germany: F.C.W. Vogel; 1886. The authors declare that they have no competing interests. References Classification of Bacillus thuringiensis str
Entomophaga. 1990;35:233–40. doi:10.1007/BF02374798. Entomophaga. 1990;35:233–40. doi:10.1007/BF02374798. 75. Mitchell A, Chang HY, Daugherty L, Fraser M, Hunter S, Lopez R, et al. The
InterPro protein families database: the classification resource after 15 years. Nucleic Acids Res. 2015;43:D213–21. 47. Gibbons NE, Murray RGE. Proposals concerning the higher Taxa of bacteria. Int J Syst Bacteriol. 1978;28:1–6. doi:10.1099/00207713-28-1-1. 48. West AW, Burges HD, Dixon TJ, Wyborn CH. Survival of Bacillus thuringiensis
and Bacillus cereus spore inocula in soil: effects of pH, moisture, nutrient
availability and indigenous microorganisms. Soil Biol Biochem. 1985;17:657–65. 76. Zhou Y, Liang Y, Lynch KH, Dennis JJ, Wishart DS. PHAST: a fast phage
search tool. Nucleic Acids Res. 2011;39(SUPPL. 2):347–52. 77. Fortier L-C, Sekulovic O. Importance of prophages to evolution and virulence
of bacterial pathogens. Virulence. 2013;4:354–65. doi:10.4161/viru.24498. 49. Ash C, Farrow JA, Dorsch M, Stackebrandt E, Collins MD. Comparative
analysis of Bacillus anthracis, Bacillus cereus, and related species on the basis
of reverse transcriptase sequencing of 16S rRNA. Int J Syst Bacteriol. 1991;
41(3):343–6. 78. Brüssow H, Canchaya C, Hardt W-D, Bru H. Phages and the evolution of
bacterial pathogens: from genomic rearrangements to Lysogenic
conversion. Microbiol Mol Biol Rev. 2004;68:560–602. 50. Saitou N, Nei M. The neighbor-joining method: a new method for
reconstructing Phylogenetic trees. Mol Biol Evol. 1987;4:406–25. 79. Barksdale L, Arden SB. Persisting bacteriophage infections, lysogeny, and
phage conversions. Annu Rev Microbiol. 1974;28:265–99. 51. Tamura K, Nei M, Kumar S. Prospects for inferring very large phylogenies by using
the neighbor-joining method. Proc Natl Acad Sci U S A. 2004;101:11030–5. ,
,
p
g
y
g p y g
y
g
the neighbor-joining method. Proc Natl Acad Sci U S A. 2004;101:11030–5. 80. Freeman VJ. Studies on the virulence of bacteriophage-infected strains of
Corynebacterium diphtheriae. J Bacteriol. 1951;61:675–88. 52. Kumar S, Stecher G, Tamura K. MEGA7: molecular evolutionary genetics
analysis version 7.0 for bigger datasets. Mol Biol Evol. 2016;7:1870–4. doi:10. 1093/molbev/msw054. 81. De Maagd RA, Bravo A, Crickmore N. How Bacillus thuringiensis has evolved
specific toxins to colonize the insect world. Trends Genet. 2001;17:193–9. 82. Agaisse H, Lereclus D. How does Bacillus thuringiensis produce so much
insecticidal crystal protein? J Bacteriol. 1995;177:6027–32. 53. Markowitz VM, Chen IMA, Palaniappan K, Chu K, Szeto E, Grechkin Y, et al. IMG: the integrated microbial genomes database and comparative analysis
system. Nucleic Acids Res. 2012;40:115–22. 83. Ben-Dov E. Bacillus thuringiensis subsp. israelensis and its Dipteran-specific
toxins. References Toxins (Basel). 2014;6:1222–43. 54. Field D, Garrity G, Gray T, Morrison N, Selengut J, Tatusova T, et al. The
minimum information about a genome sequences (MIGS) specification. Nat
Biotechnol. 2008;26:541–7. doi:10.1038/1360. 84. Lechner M, Findeiss S, Steiner L, Marz M, Stadler PF, Prohaska SJ. Proteinortho: detection of (co-)orthologs in large-scale analysis. BMC
Bioinformatics. 2011;12:124. doi:10.1186/1471-2105-12-124. 55. Gilles A, Meglécz E, Pech N, Ferreira S, Malausa T, Martin J-F. Accuracy and
quality assessment of 454 GS-FLX titanium pyrosequencing. BMC Genomics. 2011;12:245. doi:10.1186/1471-2164-12-245. 85. Leimbach A. bac-genomics-scripts: Bovine E. coli mastitis comparative
genomics editio. 2016. https://github.com/aleimba/bac-genomics-scripts/
tree/master/cds_extractor ,Accessed 14 Mar 2016. 56. Rhoads A, Au KF. PacBio sequencing and its applications. Genomics,
Proteomics Bioinforma. 2015;13:278–89. doi:10.1016/j.gpb.2015.08.002. 86. Woese CR, Kandler O, Wheelis ML. Towards a natural system of organisms:
proposal for the domains Archaea, bacteria, and Eucarya. Proc Natl Acad Sci
U S A. 1990;87:4576–9. 57. Staden R, Beal KF, Bonfield JK. The Staden package, 1998. In: Misener S, Krawtz AS,
editors. Methods in molecular biology. New York: Humana Press; 1999. p. 115–30. ,
,
p
g ,
,
,
editors. Methods in molecular biology. New York: Humana Press; 1999. p. 115–30. 87. Euzéby J. List of new names and new combinations previously effectively,
but not validly, published. Int J Syst Evol Microbiol. 2010;60:469–72. 58. Chin C-S, Alexander DH, Marks P, Klammer AA, Drake J, Heiner C, et al. Nonhybrid, finished microbial genome assemblies from long-read SMRT
sequencing data. Nat Methods. 2013;10:563–9. doi:10.1038/nmeth.2474. 88. Ludwig W, Schleifer K-H, Whitman WB. Class I. Bacillis class nov. Bergey’s
Man Syst Bacteriol. 2009;3:19–20. 59. PacBio Software Downloads. 2016. http://www.pacb.com/support/software-
downloads/. Accessed 12 Apr 2016. 89. Prévot AR. Dictionnaire des Bactéries Pathogènes In: Hauderoy P, Ehringer
G, Guillot G, Magrou. J., Prévot AR, Rosset D, Urbain A (eds), Dictionnaire des
Bactéries Pathogènes, Second Edition, Masson et Cie, Paris, 1953, p. 1–692. 60. Gao F, Luo H, Zhang C-T. DoriC 5.0: an updated database of oriC regions in
both bacterial and archaeal genomes. Nucleic Acids Res. 2013;41 Database
issue:D90–3. doi:10.1093/nar/gks990. 90. Fischer A. Untersuchungen über bakterien. Jahrbücher für Wissenschaftliche
Botanik. 1895;27:1–163. 61. DoriC: an updated database of bacterial and archaeal replication origins. http://tubic.tju.edu.cn/doric/. Accessed 15 Dec 2016. 91. Thompson JD, Higgins DG, Gibson TJ. CLUSTAL W: improving the sensitivity
of progressive multiple sequence alignment through sequence weighting,
position-specific gap penalties and weight matrix choice. Nucleic Acids Res. 1994;22:4673–80. 62. Gao F, Zhang C-T. References Palma L, Muñoz D, Berry C, Murillo J, Caballero P. Bacillus thuringiensis toxins:
an overview of their Biocidal activity. Toxins (Basel). 2014;6:3296–325. doi:10.3390/toxins6123296. 39. Mahillon J, Rezsöhazy R, Hallet B, Delcour J. IS231 and other Bacillus
thuringiensis transposable elements: a review. Genetica. 1994;93:13–26. 40. Kronstad JW, Whiteley HR. Inverted repeat sequences flank a Bacillus
thuringiensis crystal protein gene. J Bacteriol. 1984;160:95–102. 14. Crickmore N. Bacillus thuringiensis Toxin nomenclature. http://www. btnomenclature.info/. Accessed 12 Oct 2016. 41. Masri L, Branca A, Sheppard AE, Papkou A, Laehnemann D, Guenther PS, et
al. Host–pathogen Coevolution: the selective advantage of Bacillus 15. Aronson AI. The two faces of Bacillus thuringiensis: insecticidal proteins and
post-exponential survival. Mol Microbiol. 1993;7:489–96. 15. Aronson AI. The two faces of Bacillus thuringiensis: insecticidal proteins and
post-exponential survival. Mol Microbiol. 1993;7:489–96. Page 10 of 10 Page 10 of 10 Hollensteiner et al. Standards in Genomic Sciences (2017) 12:48 70. Crickmore N, Zeigler DR, Feitelson J, Schnepf E, Van Rie J, Lereclus D, et al. Revision of the nomenclature for the Bacillus thuringiensis pesticidal crystal
proteins. Microbiol Mol Biol Rev. 1998;62:807–13. thuringiensis virulence and its cry toxin genes. PLoS Biol. 2015;13:e1002169. doi:10.1371/journal.pbio.1002169. thuringiensis virulence and its cry toxin genes. PLoS Biol. 2015;13:e1002169. doi:10.1371/journal.pbio.1002169. 42. Schulte RD, Makus C, Hasert B, Michiels NK, Schulenburg H. Multiple
reciprocal adaptations and rapid genetic change upon experimental
coevolution of an animal host and its microbial parasite. Proc Natl Acad Sci
U S A. 2010;107:7359–64. doi:10.1073/pnas.1003113107. 71. Bateman A, Martin MJ, O’Donovan C, Magrane M, Apweiler R, Alpi E, et al. UniProt: a hub for protein information. Nucleic Acids Res. 2015;43:D204–12. 72. Benson DA, Cavanaugh M, Clark K, Karsch-Mizrachi I, Lipman DJ, Ostell J, et
al. GenBank. Nucleic Acids Res. 2013;41:36–42. 43. Payne J. Isolates of Bacillus thuringiensis that are active against nematodes. 1992. 43. Payne J. Isolates of Bacillus thuringiensis that are active agains 73. Carlson CR, Kolstø A-BB. A complete physical map of a Bacillus thuringiensis
chromosome. J Bacteriol. 1993;175:1053–60. 44. Payne J, Cannon R, Bagley A. Bacillus thuringiensis isolates for controlling
acarides. 1993. 74. Wang A, Pattemore J, Ash G, Williams A, Hane J. Draft genome sequence of
Bacillus thuringiensis strain DAR 81934, which Exhibits Molluscicidal Activity. Genome Announc. 2013;1:e0017512. doi:10.1128/genomeA.00175-12. 45. Schnepf H, Schwab G, Payne J, Narva K, Foncerrada L. Nematicidal proteins. 2001. 46. Barjac H, Frachon E. Classification of Bacillus thuringiensis strain 46. Barjac H, Frachon E. References Ori-finder: a web-based system for finding oriCs in
unannotated bacterial genomes. BMC Bioinformatics. 2008;9:79. 63. Seemann T. Prokka: rapid prokaryotic genome annotation. Bioinformatics. 2014;30:2068–9. 92. Ash C, Priest FG, Collins MD. Molecular identification of rRNA group 3 bacilli
(Ash, Farrow, Wallbanks and Collins) using a PCR probe test. Proposal for the
creation of a new genus Paenibacillus. Antonie Van Leeuwenhoek. 64:253–60. http://www.ncbi.nlm.nih.gov/pubmed/8085788. Accessed 6 Jun 2017. 64. Sheppard AE, Poehlein A, Rosenstiel P, Liesegang H, Schulenburg H. Complete genome sequence of Bacillus thuringiensis strain 407 cry. Genome
Announc. 2013;1:158–12. 93. Tatusov RL, Fedorova ND, Jackson JD, Jacobs AR, Kiryutin B, Koonin EV, et al. The COG database: an updated version includes eukaryotes. BMC
Bioinformatics. 2003;4:41. doi:10.1186/1471-2105-4-41. 65. Hyatt D, Chen G-L, Locascio PF, Land ML, Larimer FW, Hauser LJ. Prodigal:
prokaryotic gene recognition and translation initiation site identification. BMC Bioinformatics. 2010;11:119. doi:10.1186/1471-2105-11-119. 94. Carver T, Thomson N, Bleasby A, Berriman M, Parkhill J. DNAPlotter: circular
and linear interactive genome visualization. Bioinformatics. 2009;25:119–20. 66. Lagesen K, Hallin P, Rødland EA, Stærfeldt HH, Rognes T, Ussery DW. RNAmmer: consistent and rapid annotation of ribosomal RNA genes. Nucleic Acids Res. 2007;35:3100–8. 67. Laslett D, Canback B. ARAGORN, a program to detect tRNA genes and
tmRNA genes in nucleotide sequences. Nucleic Acids Res. 2004;32:11–6. 68. Petersen TN, Brunak S, von Heijne G, Nielsen H. SignalP 4.0: discriminating
signal peptides from transmembrane regions. Nat Methods. 2011;8:785–6. doi:10.1038/nmeth.1701. 69. Griffiths-Jones S, Bateman A, Marshall M, Khanna A, Eddy SR. Rfam: an RNA
family database. Nucleic Acids Res. 2003;31:439–41.
|
https://openalex.org/W4286717007
|
https://vbn.aau.dk/files/481607956/KEM.926.1248.pdf
|
English
| null |
Simulation of Wrinkling during Forming of Binder Stabilized UD-NCF Preforms in Wind Turbine Blade Manufacturing
|
Key engineering materials
| 2,022
|
cc-by
| 4,861
|
Simulation of Wrinkling during Forming of Binder Stabilized UD-NCF Preforms in Wind
Turbine Blade Manufacturing
B
b
P t
H d
K
h Ch i ti
Li d
d E b
B k B i
L
V
d l Published in:
Key Engineering Materials DOI (link to publication from Publisher):
10.4028/p-165q46
Creative Commons License
CC BY 4.0
Publication date:
2022 Citation for published version (APA):
Broberg, P. H., Krogh, C., Lindgaard, E., & Bak, B. L. V. (2022). Simulation of Wrinkling during Forming of
Binder Stabilized UD-NCF Preforms in Wind Turbine Blade Manufacturing. Key Engineering Materials, 926,
1248-1256. https://doi.org/10.4028/p-165q46 General rights
Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners
and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. General rights
Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners
and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. Aalborg Universitet Aalborg Universitet Simulation of Wrinkling during Forming of Binder Stabilized UD-NCF
Preforms in Wind Turbine Blade Manufacturing
Peter Hede Broberg1,2,a*, Christian Krogh1,b, Esben Lindgaard1,2,c,
and Brian Lau Verndal Bak1,2,d 1Department of Materials and Production, Aalborg University, Fibigerstraede 16, Aalborg, Denmark
2 CraCS Research group, Aalborg University, www.CraCS.aau.dk
aphb@mp.aau.dk, bck@mp.aau.dk, celo@mp.aau.dk, dbrianbak@mp.aau.dk 1Department of Materials and Production, Aalborg University, Fibigerstraede 16, Aalborg, Denmark
2 CraCS Research group, Aalborg University, www.CraCS.aau.dk
aphb@mp.aau.dk, bck@mp.aau.dk, celo@mp.aau.dk, dbrianbak@mp.aau.dk : Forming simulation, Dry-binder preforms, Non-crimp fabrics, Wrinkles Keywords: Forming simulation, Dry-binder preforms, Non-crimp fabrics, Wrinkles Abstract. Binder stabilized preforms are getting increased attention in the wind turbine industry with
the aim to increase automation in the production of large blades. In this context a preform is a stack
of dry unidirectional glass fiber non-crimp fabrics (UD-NCF), which is consolidated using a
polymeric binder. The preform is manufactured in a separate mold, and subsequently placed in the
main blade mold. During placement of preforms, fiber wrinkling may occur due to the deformation
of the preform. To accommodate this problem, we propose a predictive simulation model that can be
used to investigate how different process parameters influence the wrinkle creation. Most forming
simulation models in the literature consider frictional laws in the inter-ply interface for multi-layered
fabrics. In this work the binder interfaces between the layers are modelled using a cohesive traction-
separation law to accurately model binder degradation and wrinkle creation during preform
deformation. The model predictions are compared with full thickness preform coupon specimens. This article is an open access article under the terms and conditions of the Creative Commons Attribution (CC BY) license
(https://creativecommons.org/licenses/by/4.0) General rights
C
i h
d - Users may download and print one copy of any publication from the public portal for the purpose of private study or research. - You may not further distribute the material or use it for any profit-making activity or commercial gain - Users may download and print one copy of any publication from the public portal for the purpose of private study or research. - You may not further distribute the material or use it for any profit-making activity or commercial gain - Users may download and print one copy of any publication from the public portal for the purpose of p
Y
t f
th
di t ib t
th
t
i l
it f
fit
ki
ti it
i l
i You may not further distribute the material or use it for any profit making activity o
- You may freely distribute the URL identifying the publication in the public portal - y
y p
g
y
- You may freely distribute the URL identifying the publication in the public portal - Take down policy
If you believe that this document breaches copyright please contact us at vbn@aub.aau.dk providing details, and w
the work immediately and investigate your claim. y
this document breaches copyright please contact us at vbn@aub.aau.dk providing details, and we will remove access to
ely and investigate your claim. Key Engineering Materials
Submitted: 2021-12-03
ISSN: 1662-9795, Vol. 926, pp 1248-1256
Revised: 2022-01-17
doi:10.4028/p-165q46
Accepted: 2022-02-18
© 2022 The Author(s). Published by Trans Tech Publications Ltd, Switzerland. Online: 2022-07-22 Key Engineering Materials
ISSN: 1662-9795, Vol. 926, pp 1248-1256
doi:10.4028/p-165q46
© 2022 The Author(s). Published by Trans Tech Publications Ltd, Switzerland. Submitted: 2021-12-03
Revised: 2022-01-17
Accepted: 2022-02-18
Online: 2022-07-22 Preform Material The preforms are made of stacked non-crimp fabrics consisting of unidirectional glass fibers (UD-
NCF). The UD glass fibers are stabilized by a layer of backing fibers oriented at ±80˚. The UD-NCFs
have an area weight of 1322 g/m2, with a backing fiber weight percent of approximately 2wt%. The
backing fibers are stitched to the UD fibers by a polyester thread in a tricot-chain like pattern. A
polymeric binder is placed between the NCFs plies to ease the handling of the preform. The thickness
of each UD-NCF ply is approximately 1 mm, and the preform is made of 16 stacked UD-NCF plies
which gives the preform a total height of approximately 16 mm. The preforms are pre-consolidated
under vacuum at elevated temperatures. The preform can be seen in Fig. 1, with indication of the
local coordinate system. Fig. 1: Cut-out of binder stabilized preform. The preform is made of stacks of dry UD-NCFs that
have been consolidated with a polymeric binder. Fig. 1: Cut-out of binder stabilized preform. The preform is made of stacks of dry UD-NCFs that
have been consolidated with a polymeric binder. Key Engineering Materials Vol. 926 1249 The aim of the present paper is to present current state of a binder stabilized preform simulation
model that can be used to simulate wrinkles created during forming. The proposed model uses a
traction-separation law to describe deformation and degradation of the binder interface. Firstly, the
preform material and the specific deformation modes of the preform are presented. After this follows
a description of the proposed model which is then compared with a preform vacuum experiment. This
paper concludes with a discussion on the predictive capabilities of the proposed model, together with
a discussion on limitations of the model and model improvements for future work. Introduction To cut down on production cost of large wind turbine blades the use of binder stabilized preforms
may be used to increase automation and decrease process times. Binder stabilized preforms are stacks
of dry unidirectional glass fiber non-crimp fabrics (UD-NCF) which are pre-consolidated with a
polymeric binder, prior to placement in the main blade mold. Wrinkling may occur at geometric
transitions during placement of the preforms in the blade mold. This happens because the binder
impedes relative ply sliding, which lead to excessive ply length at geometric transitions. These fiber
wrinkles may cause a severe knockdown on the wind turbine blade strength [1]. y
g
Simulation models may be used to predict fiber wrinkling during different manufacturing steps. They can, generally, be divided into kinematic and mechanical models. Kinematic models are
computational efficient [2], but are not capable of describing the complex binder interface in the
binder stabilized preforms under consideration. Simulation models of forming of woven fabrics have
been studied extensively in the literature [3,4]. However, models of UD-NCF have only sparsely been
reported in the literature. Most simulation models of NCF are formulated at the meso-scale, where
the stitches are modeled discretely [5,6]. Recently, homogenous macro scale models of UD-NCF
have been proposed by e.g. [7]. Numerical models on forming of multilayered composites have been
the subject for recent research [8–11]. Common for most simulation models of multilayered
composites is that separation often is neglected, and sliding is modeled by frictional laws. Delamination may occur locally in a preform in compression due to fiber instabilities. A description
of ply delamination is, therefore, needed to accurately predict fiber wrinkling. Recent literature also
points out the need for characterizing the binder interface for choosing an optimal forming strategy
and reducing manufacturing cost [12]. Previously, cohesive zone models have been used to predict
delamination during creasing of paperboard material [13], and UD carbon fabric for automated fiber
placement [14]. However, to the authors’ knowledge, cohesive zone modeling has not previously
been used to describe a binder interface in preforms. Key Engineering Materials Vol. 926 Numerical Simulation Model A fiber-binder preform can be modeled at different length scales, see Fig. 2. At the micro-scale the
fibers are assumed homogenous and modeled discretely. At meso-scale the fiber rovings are assumed
homogenous, and the stitches of the NCF and the dispersed binder are modeled discretely. At macro-
scale each UD-NCF ply is modeled separately as a homogenous material, and the binder interface is
modeled homogenously. At structural-scale the whole preform is modeled as a homogenous
continuum. For the present model it is desired to make a macro-scale model of the preform, as it
offers low computational time compared to micro-, and meso-scale modeling. The macro-scale model
still provides significant information on the inter-ply deformation (degradation of the binder
interface) which a structural-scale model would not be able to describe. When modeling the preform at macro-scale, the intra-ply interactions are neglected. This could be
relative fiber sliding or deformation of stitching. Thus, it is important that the macro-scale model is
capable of describing significant deformation modes arising from intra-ply deformations at lower
scales. This can be achieved by selecting a proper material model accounting for the inherent
anisotropy of the structure. For the present study an elastic orthotropic material model is used. Achievements and Trends in Material Forming 1250 Fig. 2: Different modelling scales for a binder stabilized preform. Fig. 2: Different modelling scales for a binder stabilized preform. The present preform model is a 2D model in the 1-3 plane of the preform, see Fig. 1, which means
that the effects of the preform width in the backing direction are neglected. In-plane shearing is not
accounted for in this 2D model, which reduces the influence of the stitching geometry. In the 2D
macro-scale model the deformation modes shown in Fig. 3 can be described. The in-plane
deformation mode are elongation and compression of the UD-NCF plies. The plies have a high
membrane tensile stiffness as the fibers will be in tension, whereas, the membrane compressive
stiffness is low due to fiber instabilities. The out-of-plane deformation modes are bending, through
thickness compaction and transverse shearing. The bending, compaction, and transverse shear
stiffnesses of the UD-NCF are low due to relative fiber movement. Some permanent deformation is
also expected for the out-of-plane modes due to friction between fibers and relative fiber motion. To
describe the specific deformation modes of the UD-NCF at macro-scale, these should ideally be
decoupled and described separately. Numerical Simulation Model (1) max ൜
〈𝑡𝑡3〉
𝑡𝑡3
0 , 𝑡𝑡2
𝑡𝑡2
0 , 𝑡𝑡1
𝑡𝑡1
0ൠ= 1. (1) In this criterion 𝑡𝑡3 is the nominal tractions normal to the interface, and 𝑡𝑡2 and 𝑡𝑡1 are the shear stresses
in both shear directions. Superscript 0 on the 𝑡𝑡 denotes the onset traction of the i’th deformation mode. For damage propagation the critical energy release rate is used as criteria, 𝐺𝐺𝐼𝐺𝑆𝐺𝑐 In this criterion 𝑡𝑡3 is the nominal tractions normal to the interface, and 𝑡𝑡2 and 𝑡𝑡1 are the shear stresses
in both shear directions. Superscript 0 on the 𝑡𝑡 denotes the onset traction of the i’th deformation mode. For damage propagation the critical energy release rate is used as criteria, 𝐺𝐺𝐼𝐺𝑆𝐺𝑐 𝐺𝐺= 𝐺𝐺𝐼𝐼+ 𝐺𝐺𝑆𝑆≥𝐺𝐺𝑐𝑐. (2) 𝐺𝑠𝐺𝐼𝐼𝐺𝐼𝐼𝐼𝐺𝑐 (2) 𝐺𝐺= 𝐺𝐺𝐼𝐼+ 𝐺𝐺𝑆𝑆≥𝐺𝐺𝑐𝑐. Where 𝐺𝐺𝑠𝑠= 𝐺𝐺𝐼𝐼𝐼𝐼+ 𝐺𝐺𝐼𝐼𝐼𝐼𝐼𝐼, and the critical energy release rate, 𝐺𝐺𝑐𝑐, is interpolated using the
Benzeggagh-Kenane criterion [15], 𝐺𝐺𝐺𝐺𝐵𝐵𝐺𝑠 𝐺𝐺𝑐𝑐= 𝐺𝐺𝐼𝐼𝐼𝐼+ (𝐺𝐺𝐼𝐼𝐼𝐼𝐼𝐼−𝐺𝐺𝐼𝐼𝐼𝐼)𝐵𝐵η, 𝐵𝐵=
𝐺𝐺𝑠𝑠
𝐺𝐺𝐼𝐼+𝐺𝐺𝑠𝑠. (3)
Characterization of Material Properties 𝐺𝐺𝑐𝑐= 𝐺𝐺𝐼𝐼𝐼𝐼+ (𝐺𝐺𝐼𝐼𝐼𝐼𝐼𝐼−𝐺𝐺𝐼𝐼𝐼𝐼)𝐵𝐵η, 𝐵𝐵=
𝐺𝐺𝑠𝑠
𝐺𝐺𝐼𝐼+𝐺𝐺𝑠𝑠. (3) (3) Numerical Simulation Model The inter-ply deformation modes are ply separation and relative
ply sliding. These two deformation modes correspond to mode-I and mode-II deformation from
fracture mechanics. Both mode-I and mode-II delamination occurs during preform wrinkling. Fig. 3: Deformation modes for a macro-scale model of the preform. Fig. 3: Deformation modes for a macro-scale model of the preform. The current 2D preform model is shown in Fig. 4. The model is desired to be based on
commercially available finite element analysis (FEA) software. Each UD-NCF layer is modeled
separately by solid continuum elements (C3D8R in ABAQUS) with linear elastic material properties,
and the binder material is modeled as a cohesive interface. The use of solid elements improves the
contact surface representation compared to shell elements with an offset. An orthotropic material
model is used for the UD-NCFs. The model is constrained with plane stress boundary conditions, and
is solved using ABAQUS/Explicit. To decrease computational time the preform is modeled with 8
layers of double thickness. Key Engineering Materials Vol. 926 1251 Fig. 4: Model of the fiber preform. Each UD-NCF ply is modeled separately as a continuum, and the
interface between the plies are modeled as a cohesive interface. Fig. 4: Model of the fiber preform. Each UD-NCF ply is modeled separately as a continuum, and the
interface between the plies are modeled as a cohesive interface. Fig. 4: Model of the fiber preform. Each UD-NCF ply is modeled separately as a continuum, and the
interface between the plies are modeled as a cohesive interface. A bilinear traction-separation law is used to describe the cohesive interface between the plies, see
Fig. 5 (a). As wrinkle creation in the fiber preform involves mixed mode crack propagation, a mixed
mode cohesive law is used, Fig. 6 (b). Fig. 5: Bilinear traction separation law (a), and a mixed mode cohesive law (b) used for modeling the
binder interface. Fig. 5: Bilinear traction separation law (a), and a mixed mode cohesive law (b) used for modeling the
binder interface. For the onset of damage in the interface a maximum nominal stress criterion is used, 𝑡𝑡𝑡 For the onset of damage in the interface a maximum nominal stress criterion is used max ൜
〈𝑡𝑡3〉
𝑡𝑡3
0 , 𝑡𝑡2
𝑡𝑡2
0 , 𝑡𝑡1
𝑡𝑡1
0ൠ= 1. (1) 𝑡𝑡𝑡𝑡 max ൜
〈𝑡𝑡3〉
𝑡𝑡3
0 , 𝑡𝑡2
𝑡𝑡2
0 , 𝑡𝑡1
𝑡𝑡1
0ൠ= 1. Characterization of Material Properties The material properties needed as input to the model are membrane, transverse shear, and compaction
stiffnesses of the plies, and traction-separation laws for mixed mode crack propagation of the binder
interface. For the present study the bending stiffness of the UD-NCF plies and mode-I critical energy Achievements and Trends in Material Forming 1252 release rate of the binder interface have been characterized by a cantilever bending test [16] and t-
peel test, respectively, see Fig. 6. The fabric and binder are characterized as being homogenous i.e. the effect of stitches, binder dispersion etc. are implicitly accounted for in the characterized responses. release rate of the binder interface have been characterized by a cantilever bending test [16] and t-
peel test, respectively, see Fig. 6. The fabric and binder are characterized as being homogenous i.e. the effect of stitches, binder dispersion etc. are implicitly accounted for in the characterized responses. Fig. 6. Cantilever bending test used for obtaining a linear moment-curvature relationship (a). T-peel
test used for obtaining the mode-I critical energy release rate of the binder interface (b). Fig. 6. Cantilever bending test used for obtaining a linear moment-curvature relationship (a). T-peel
test used for obtaining the mode-I critical energy release rate of the binder interface (b). Characterization of Bending Stiffness. The cantilever bending test is used to estimate the
bending stiffness. In this test a piece of fabric is left to deform due to its own weight until it settles at
a given deformation. The deflection of the fabric is measured by image processing similar to what is
done in [17,18]. Based on the deflection curve, a constant stiffness 𝐷𝐷11 is estimated using Peirce’s
formula [17], 𝐷𝐿𝜃𝑤𝜃𝑦𝑚𝑚𝑚 𝐷𝐷11 =
𝐿𝐿3
8
cos𝜃𝜃/2
tan𝜃𝜃𝑤𝑤, 𝜃𝜃=
𝑦𝑦𝑚𝑚𝑚𝑚𝑚𝑚
𝑥𝑥𝑚𝑚𝑚𝑚𝑚𝑚 . (4) 𝐿𝜃𝑤 𝐷𝐷11 =
𝐿𝐿3
8
cos𝜃𝜃/2
tan𝜃𝜃𝑤𝑤, 𝜃𝜃=
𝑦𝑦𝑚𝑚𝑚𝑚𝑚𝑚
𝑥𝑥𝑚𝑚𝑚𝑚𝑚𝑚 . /2𝜃𝑤𝑤, 𝜃𝜃=
𝑦𝑦𝑚𝑚𝑚𝑚𝑚𝑚
𝑥𝑥𝑚𝑚𝑚𝑚𝑚𝑚 . (4) 𝜃𝑤 (4) (4) where 𝐿𝐿 is the length of the fabric being bent, 𝜃𝜃 is the angle of the inclined plane calculated by the
endpoints of the deflection curve, and 𝑤𝑤 is the area weight of the fabric. The stiffness of the plies is
measured to 𝐷𝐷11 = 50Nmm. 𝐷𝐷11 is implemented in the orthotropic material model used for the UD-
NCFs by setting 𝐸𝐸1 =
12𝐷𝐷11
𝑡𝑡3 , where t is the thickness of the UD-NCFs. Characterization of Material Properties The calculated value of 𝐸𝐸1
makes the UD-NCFs response in tension and compression unphysical as the membrane stiffness is
affected. A fitted value of 𝐸𝐸1 = 6GPa is, therefore, used instead. Characterization of Mode-I Fracture Toughness. To estimate the mode-I fracture toughness of
the binder material t-peel tests have been conducted [19], see Fig. 6 b). In the t-peel test, two UD-
NCF plies are being pulled apart at a fixed rate in a standard tensile test machine. The mode-I critical
energy release rate is estimated by, 𝐺𝐹 𝐺𝐺𝐼𝐼𝐼𝐼=
2 𝐹𝐹
𝑏𝑏. (5) 𝐺𝐺 𝐺𝐺𝐼𝐼𝐼𝐼=
2 𝐹𝐹
𝑏𝑏. (5) where b is the width of the test specimen. The mode-I fracture toughness is measured to 160 J/m2. As
𝐺𝐺𝐼𝐼𝐼𝐼𝐼𝐼 is not characterized it is given the same value as 𝐺𝐺𝐼𝐼𝐼𝐼 in the damage propagation criterion of Eq. (3). where b is the width of the test specimen. The mode-I fracture toughness is measured to 160 J/m2. As
𝐺𝐺𝐼𝐼𝐼𝐼𝐼𝐼 is not characterized it is given the same value as 𝐺𝐺𝐼𝐼𝐼𝐼 in the damage propagation criterion of Eq. (3). 𝐺𝐺𝐼𝐼𝐼𝐼𝐼𝐼 is not characterized it is given the same value as 𝐺𝐺𝐼𝐼𝐼𝐼 in the damage propagation criterion of Eq. (3). 𝐺𝐺𝐼𝐼𝐼𝐼𝐼𝐼 is not characterized it is given the same value as 𝐺𝐺𝐼𝐼𝐼𝐼 in the damage propagation criterion of Eq. (3). Results To test the performance of the simulation model it is compared with results from a real forming case
of the fiber-binder preform structure. Key Engineering Materials Vol. 926 1253 Preform Vacuum Experiments. The vacuum experiments are carried out by placing a preform
specimen on a wedge and applying vacuum. The initially straight preform is then formed over the
wedge, see Fig. 7. Fig. 7: Deformed configuration of the preform during the vacuum experiments. The initial straight
preform is formed on the wedge. 𝑡𝐿𝑡 Fig. 7: Deformed configuration of the preform during the vacuum experiments. The initial straight
preform is formed on the wedge. 𝑡𝐿𝑡 The wedge being used have an angle of θ𝑡𝑡= 25° and a length of 𝐿𝐿𝑡𝑡= 320 mm. The preform
specimens used for the experiments have dimensions [1000 mm x 50 mm] and full thickness. The wedge being used have an angle of θ𝑡𝑡= 25° and a length of 𝐿𝐿𝑡𝑡= 320 mm. The preform
specimens used for the experiments have dimensions [1000 mm x 50 mm] and full thickness. Comparison of the Experiments with the Numerical Model. The comparison can be seen in
Fig. 8. The comparison is done at three different locations on the preform; at the top transition, the
shear region, and the bottom transition. At the top transition wrinkles facing down towards the mold
are observed in the experiments. These wrinkles are also predicted by the model. The size of the
wrinkle in the model is approximately 2 cm, whereas, the wrinkles observed in the experiments are
approximately 1 cm. Delamination at the wrinkle sites are also predicted by the model, which is also
observed in the experiments. In the shearing region the preform is undergoing transverse shearing in
the experiments, with a shearing angle of approximately 6°. The simulation model predicts a
transverse shear angle of approximately 1.5°. At the bottom transition a surface wrinkle of
approximately 2 cm is observed in the experiments. The simulation model predicts a surface wrinkle
at the same location with a size of 4 cm. The model predicts delamination at the wrinkle site which
is also observed in the experiments. Fig. 8. Comparison of the deformed configuration of the preform from the simulation and the vacuum
experiments. Red contours in the model indicate full damage of the binder interface. Fig. 8. Comparison of the deformed configuration of the preform from the simulation and the vacuum
experiments. Discussion The model is capable of predicting the location and overall shape of the wrinkles arising during
forming of the preform. In the experiments delamination of the binder interface is observed at the
wrinkle sites, while no delamination is observed in the shear region. Both these phenomena are
captured by the model. Wrinkles occurs in binder stabilized preforms due to a combination of binder
delamination at wrinkle sites, and limited fiber sliding and binder deformation at shear regions. g
g
The difference in wrinkle size is expected to be due to the bending stiffness being slightly higher
in the model than in the UD-NCFs tested. The bending and membrane stiffness are not decoupled
since solid elements with linear elastic material properties are used in the model. The membrane
stiffness can therefore be chosen to either represent the estimated membrane or the estimated bending
stiffness of the model. The former will result in a high bending stiffness which influences the size of
the wrinkles. The latter will result in a low membrane stiffness which results in membrane
deformation of the plies rather than wrinkling. The transverse shearing of the preform is
underpredicted by the model. The overly high transverse shear stiffness of the model increases the
compressive longitudinal stress in the fibers. This leads to out-of-plane deformation of the ply due to
instability, which may result in larger wrinkles which initiates at an earlier stage in the forming
process. However, since the modeled membrane stiffness of the UD-NCFs is relatively low (to
account for the low bending stiffness of the plies without decoupling), the compressive longitudinal
stresses may result in compressive deformation of the fibers rather than wrinkling. The mode-II
critical energy release rate have not been characterized as input for the model. This will probably be
higher than the mode-I critical energy release rate. A higher mode-II critical energy release rate may
decrease the size of the wrinkles by limiting the propagation of initiated wrinkles. In the vacuum
experiment the wrinkle creation is governed by forming rather than consolidation [20]. Furthermore,
limited compaction occurs during the vacuum forming because the preforms are pre-consolidated. This means that the linear compaction stiffness used for the present model is sufficient for describing
the compaction. If the model is to be used in a consolidation driven simulation, a non-constant
compaction stiffness may need to be implemented [8]. Results Red contours in the model indicate full damage of the binder interface. Achievements and Trends in Material Forming Achievements and Trends in Material Forming 1254 Conclusion In this paper a model for simulating forming of binder stabilized preforms using a cohesive traction-
separation law for the binder interface is described. The model considers the UD-NCF plies as a
homogenous continuum with a linear elastic orthotropic material model, and the binder material as a
homogenous cohesive interface between the plies. The model can predict the location of the wrinkles
arising during forming of binder stabilized preforms, and the binder delamination that occurs at the
wrinkle sites. The size of the wrinkles predicted by the model is larger than observed in experiments. The reason is expected to be due to the bending and membrane stiffness not being decoupled in the
present model. So far, only orthotropic linear elastic material models for the UD-NCFs is used. In
future work the modeling framework will be extended to also include non-linear material models of
the plies, as well as decoupling of the bending and the membrane stiffnesses. The enhanced model
will thereby be able to accurately predict possible defects such that they can be dealt with before the
production stage of the wind turbine blade Discussion The current model is made for 2D analysis of preform forming. To model forming over double
curved geometric transitions, this model needs to be extended to include 3D deformation modes. The
2D model may be able to accurately model forming of wide preforms, if the transitions considered
are not double curved, and plane strain assumptions are used. This study was completed as part of the MADEBLADES research project supported by the Energy
Technology Development and Demonstration Program, Grant no. 64019-0514. References [1] J. J. Bender, S. R. Hallett, and E. Lindgaard, Investigation of the effect of wrinkle features on
wind turbine blade sub-structure strength, Compos. Struct. 218 (2019) 39–49. [2] C. Krogh et al., A simple MATLAB draping code for fiber-reinforced composites with
application to optimization of manufacturing process parameters, Struct. Multidiscipl. Optim 64
(2021) 457–471. [3] P. Boisse, J. Huang, and E. Guzman-Maldonado, Analysis and modeling of wrinkling in
composite forming, J. Compos. Sci. 5(3) (2021) 1–16. [4] P. Harrison, M. F. Alvarez, and D. Anderson, Towards comprehensive characterisation and
modelling of the forming and wrinkling mechanics of engineering fabrics, Int. J. Solids. Struct. 154
(2018) 2–18. [5] S. Bel, N. Hamila, P. Boisse, and F. Dumont, Finite element model for NCF composite
reinforcement preforming: Importance of inter-ply sliding, Compos. A: Appl. Sci. Manuf. 43(12)
(2012) 2269–2277. [6] G. Creech and A. K. Pickett, Meso-modelling of Non-crimp Fabric composites for coupled drape
and failure analysis, J. Mater. Sci. 41(20) (2006) 6725–6736. [7] F. J. Schirmaier, D. Dörr, F. Henning, and L. Kärger, A macroscopic approach to simulate the
forming behaviour of stitched unidirectional non-crimp fabrics (UD-NCF), Compos. A: Appl. Sci. Manuf. 102 (2017) 322–335. [8] J. P. H. Belnoue, O. J. Nixon-Pearson, A. J. Thompson, D. S. Ivanov, K. D. Potter, and S. R. Hallett, Consolidation-driven defect generation in thick composite parts, J. Manuf. Sci. Eng. 140(7)
(2018). [9] E. Guzman-Maldonado, P. Wang, N. Hamila, and P. Boisse, Experimental and numerical
analysis of wrinkling during forming of multi-layered textile composites, Compos. Struct. 208 (2018)
213–223. [10] A. J. Thompson, J. P. H. Belnoue, and S. R. Hallett, Modelling defect formation in textiles during
the double diaphragm forming process, Compos. B: Eng. 202 (2020). [11] K. Vanclooster, S. V. Lomov, and I. Verpoest, Simulation of multi-layered composites forming,
Int. J. Mater. Form. 3 (2010) 695-698. [12] F. Henning, L. Kärger, D. Dörr, F. J. Schirmaier, J. Seuffert, and A. Bernath, Fast processing and
continuous simulation of automotive structural composite components, Compos. Sci. Technol. 171
(2019) 261–279. [13] L. A. A. Beex and R. H. J. Peerlings, An experimental and computational study of laminated
paperboard creasing and folding, Int. J. Solids. Struct. 46(24) (2009) 4192-4207. [14] B. Durif, N. Moulin, S. Drapier, L. Bouquerel, and M. Blais, Challenges in modelling the forming
of unidirectional HiTape® reinforcements, ESAFORM 2021, Liège, Belgium [15] M. L. Benzeggagh and M. Acknowledgements This study was completed as part of the MADEBLADES research project supported by the Energy
Technology Development and Demonstration Program, Grant no. 64019-0514. Key Engineering Materials Vol. 926 Key Engineering Materials Vol. 926 1255 [19] S. Schmidt, T. Mahrholz, A. Kühn, and P. Wierach, Powder binders used for the manufacturing
of wind turbine rotor blades. Part 1. Characterization of resin-binder interaction and preform
properties, Polym. Compos. 39(3) (2018) 708–717. [18] B. Liang, P. Chaudet, and P. Boisse, Curvature determination in the bending test of continuous
fibre reinforcements, Strain 53(1) (2017) 1–12. [20] M. Thor, M. G. R. Sause, and R. M. Hinterhölzl, Mechanisms of origin and classification of out-
of-plane fiber waviness in composite materials — A review, J. Compos. Sci. 4(3) (2020). [17] E. de Bilbao, D. Soulat, G. Hivet, and A. Gasser, Experimental Study of Bending Behaviour of
Reinforcements, Exp. Mech. 50(3) (2010) 333–351. References Kenane, Measurement of mixed-mode delamination fracture
toughness of unidirectional glass/epoxy composites with mixed-mode bending apparatur, Compos. Sci. Technol. 56 (1996) 439–449. [16] C. Krogh, P. H. Broberg, J. Kepler, and J. Jakobsen, Comprehending the bending: A comparison
of different test setups for measuring the out-of-plane flexural rigidity of a UD fabric, ESAFORM
2022, Braga, Portugal Achievements and Trends in Material Forming Achievements and Trends in Material Forming 1256 [17] E. de Bilbao, D. Soulat, G. Hivet, and A. Gasser, Experimental Study of Bending Behaviour of
Reinforcements, Exp. Mech. 50(3) (2010) 333–351. [18] B. Liang, P. Chaudet, and P. Boisse, Curvature determination in the bending test of continuous
fibre reinforcements, Strain 53(1) (2017) 1–12. [18] B. Liang, P. Chaudet, and P. Boisse, Curvature determination in the bending test of continuous
fibre reinforcements, Strain 53(1) (2017) 1–12. [19] S. Schmidt, T. Mahrholz, A. Kühn, and P. Wierach, Powder binders used for the manufacturing
of wind turbine rotor blades. Part 1. Characterization of resin-binder interaction and preform
properties, Polym. Compos. 39(3) (2018) 708–717. [19] S. Schmidt, T. Mahrholz, A. Kühn, and P. Wierach, Powder binders used for the manufacturing
of wind turbine rotor blades. Part 1. Characterization of resin-binder interaction and preform
properties, Polym. Compos. 39(3) (2018) 708–717. [20] M. Thor, M. G. R. Sause, and R. M. Hinterhölzl, Mechanisms of origin and classification of out-
of-plane fiber waviness in composite materials — A review, J. Compos. Sci. 4(3) (2020). [20] M. Thor, M. G. R. Sause, and R. M. Hinterhölzl, Mechanisms of origin and classification of out-
of-plane fiber waviness in composite materials — A review, J. Compos. Sci. 4(3) (2020).
|
https://openalex.org/W2061015162
|
https://ojs.wpro.who.int/ojs/index.php/wpsar/article/download/251/389
|
English
| null |
Improving ethnocultural data to inform public health responses to communicable diseases in Australia
|
Western Pacific surveillance response journal
| 2,014
|
cc-by
| 4,200
|
Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia State/territory
Ethnocultural data collected*
Australian Capital Territory
Indigenous status, COB
New South Wales
Indigenous status, COB, LSH
Northern Territory
Indigenous status
Queensland
Indigenous status and COB†
South Australia
Indigenous status only‡
Tasmania
Indigenous status and COB
Victoria
Indigenous status, COB, year
arrived in Australia§
Western Australia
Indigenous status, COB, EO In Australia, there is no national strategy to support
the collection of ethnocultural data in communicable
disease surveillance. Ethnocultural data refers to any
data that identifies an individual’s cultural heritage,
background or affiliation, e.g. country of birth (COB);
language spoken at home (LSH) or religious affiliation
etc. In Australia, Aboriginal and Torres Strait Islander
status is routinely collected in communicable disease
surveillance. COB is commonly collected for most
notifiable diseases, however other variables used to
describe the ethnocultural identity of cases vary (Box 1). These data are collected either via general practitioners
recording this information on the disease notification
form and/or public health unit staff recording the data
during follow-up interviews with individual cases. COB – country of birth, LSH – language spoken at home, EO – ethnic origin/
ethnicity (Indigenous status or other). Indigenous status includes options of
Aboriginal only, Aboriginal and Torres Strait Islander, Torres Strait Islander only
or neither Aboriginal or Torres Strait Islander for identification purposes. * As listed on the state or jurisdiction-specific notifiable diseases form online
and/or through personal communication with state and territory Health
Departments. * As listed on the state or jurisdiction-specific notifiable diseases form online
and/or through personal communication with state and territory Health
Departments. †
Data on ethnicity and whether English is the preferred language spoken at
home (Y/N) are collected in Queensland for some notifiable diseases. ‡
COB and LSH not routinely collected in South Australia but included for
some priority notifiable diseases, i.e. sexually transmitted infections and
food-related diseases. §
Only collected for individuals born overseas. Only collected for individuals born overseas. unpredictably over subsequent generations.2 Therefore,
Australian standards3 for the collection of such data
reflect the need for a multidimensional concept of
ethnocultural identity, including several variables to
ensure reasonable specificity and sensitivity. Ethnocultural
identity
is
a
self-constructed
phenomenon related to the many social and cultural
factors that influence people’s lives including migration
status, religious affiliation, language, cultural practices
and political ideologies.2 Collecting valid ethnocultural
data can be challenging because ethnocultural identity is
not a singular and easily defined concept. a New South Wales Public Health Offi cer Training Program, New South Wales Ministry of Health, Australia.
b School of Public Health and Community Medicine, University of New South Wales, Australia.
c Population Health, Hunter New England Local Health District, New South Wales, Australia.
d Communicable Diseases Branch, Health Protection, New South Wales Ministry of Health, North Sydney, Australia.
e
New South Wales Refugee Health Service, Sydney, Australia.
f
Hunter Medical Research Institute, Newcastle, New South Wales, Australia.
Submitted: 24 February 2014; Published: 19 May 2014
doi: 10.5365/wpsar.2014.5.1.011 Improving ethnocultural data to inform
public health responses to communicable
diseases in Australia Emma Quinn,ab Peter Massey,c Alexander Rosewell,d Mitchell Smithe and David Durrheimcf
Correspondence to Emma Quinn (e-mail: equin@doh.health.nsw.gov.au). I
t is well established that ethnocultural groups of
migrants are associated with a differential risk of
communicable disease, including measles, tuberculosis
and hepatitis B. Global public health agencies1 are now
focusing on improving the collection of ethnocultural
data to better define communicable disease risk in
migrant populations to support community-level disease
prevention and control. I
t is well established that ethnocultural groups of
migrants are associated with a differential risk of
communicable disease, including measles, tuberculosis
and hepatitis B. Global public health agencies1 are now
focusing on improving the collection of ethnocultural
data to better define communicable disease risk in
migrant populations to support community-level disease
prevention and control. I Perspective Perspective www.wpro.who.int/wpsar Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia Ethnocultural
identity may change over time and it often changes Despite these challenges, the ethnocultural data
currently collected during routine communicable disease
surveillance have assisted in disease prevention and
control in Australia. Collecting COB data, though limited
in scope, has helped to identify a differential disease WPSAR Vol 5, No 2, 2014 | doi: 10.5365/wpsar.2014.5.1.011
1 Improving ethnocultural communicable diseases data in Australia Quinn et al burden in recently arrived migrants or refugees, leading to
national targeted prevention and treatment programmes
for migrants emigrating from countries with high-burden
disease, e.g. tuberculosis and chronic hepatitis B in
South Asian migrants.4 such as ethnicity or ancestry include self-determination
of cultural identity and the ability to describe the
ethnocultural background of non-Aboriginal and Torres
Strait Islander Australian-born residents. A national approach to ethnocultural data collection
may enable the strengthening of disease control for at-
risk populations. We recommend that surveillance of
COB and LSH be maintained in New South Wales and
considered in other relevant jurisdictions. However, the
collection of data on ancestry or ethnicity for defining
communicable disease risk in multicultural groups
(above and beyond COB and LSH) is warranted in
Australia, particularly as social and cultural practices
influence disease risk, in combination with a variety of
other factors.9 While COB helps to identify disease risk in newly
arrived refugees or migrants, communicable disease risk
related to ethnocultural group remains underexplored
for generations of Australian-born residents. This is
an important issue in a context where net overseas
immigration increased two to threefold in the past
decade, and second and third generation Australians now
make up 20% and 53% of the population, respectively.5 The ad hoc collection of ancestry data as
determined by the Australian Bureau of Statistics (ABS)
in a recent outbreak investigation in New South Wales
has illustrated its utility over COB and LSH for defining
at-risk populations for selected diseases. Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia During the
2012 measles outbreak in New South Wales, ancestry
data revealed that 21% of all notifications were
associated with Australians of Pacific Islander ethnicity,
and 17% occurred in Pacific Islanders with Samoan
ethnicity.6 This understanding enabled a quantification
of the measles risk for this ethnocultural group at more
than 50 times the non-Samoan population (notification
rates of 189 per 100 000).6 This led to targeted public
health action, including vaccination clinics in churches
and schools attended by a large number of young-
adult Pacific Islanders, particularly for those of Samoan
descent. Culturally specific and language-appropriate
communication materials were also developed. The collection of data according to the ABS Australian
Standard Classification of Cultural and Ethnic Groups10
in our routine communicable diseases surveillance would
be valuable for estimating disease risk in generations of
Australians that identify with particular cultural and/or
ancestral groups. Denominator data would be available
online from the ABS website via the population census
carried out every five years. Estimation of disease risk
related to ancestry would be helpful during outbreaks of
notifiable diseases where transmission risk is associated
with social or cultural practices, e.g. consumption of
culturally-specific foods, cultural gatherings or family-
related travel to disease-endemic countries. This type of
information would help inform specific community-level
prevention and control activity. Further discussion is needed regarding acceptability,
database development needs, resource implications
and training required to introduce new variables into
the routine surveillance of communicable diseases in
Australia. The development of strategies to collect these
data could follow existing best practice guidelines on
how to implement, collect and use data appropriately
on Aboriginal and Torres Strait Islander peoples. Consideration of enhanced surveillance of ethnocultural
background could initially be given for a small number
of specific diseases such as measles and meningococcal
disease, which cause significant morbidity and/or
mortality, where notifications are routinely followed up
by public health staff and where socio-cultural practices
may play a role in transmission. Foodborne disease outbreaks caused by the
consumption of culture-specific foods are also common
in New South Wales.7 The utility of collecting data on the
ethnocultural background of cases has been highlighted
in New South Wales as it prompts the inclusion of
ethnic food-specific questions into routine investigation
tools. These specific food-related risks are inadequately
identified by COB or LSH alone. www.wpro.who.int/wpsar Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia religion, lifestyle) • Multiple response categories may present
diffi culties for analysis • Self-reported ethnicity may change over
time • May not be exclusive • More of a process than a static well-defi ned
concept • Denominator data available online through
ABS website • Question may lead to offence, particularly
among refugees where racial, ethnic or
religious tensions exist in the community Length of stay in current country
Based on the length of time
(years) that the individual has
resided in their current country
from arrival
• Objective and conceptually valid
• Potential for reliability and consistency in
assessment
• Potential to distinguish between newly
arrived and long-term migrants
• Denominator data available online through
ABS website
• Year of arrival may be suffi cient here
Profi ciency in English
Based on the individual’s self-
assessed ability to speak English
when the main language spoken
at home was a language other
than English
• Conceptually valid
• Can be exhaustive and exclusive
Religious affi liation
Based on the individuals self-
identifi ed main religious belief or
the religious group to which they
belong
• Conceptually valid
• Potential for valid and reliable measurement
over time if religious groups do not change
markedly
• Self-assessed, i.e. individual declares
affi liation • May be sensitive for recently arrived
migrants/refugees and therefore may not be
asked consistently by surveillance staff • May require discussion around why this
information was being collected (in terms of
meaningfulness to respondents) g
p
)
• Provides no information about cultural or
social differences (e.g. religion, lifestyle) • Potential for great measurement bias –
meant to only represent spoken English
(not reading, writing or listening) • Reliability/objectivity may be compromised
M
i
di
i
d
h
hi Reliability/objectivity may be compromised
• May require discussion around why this
information was being collected (in terms of
meaningfulness to respondents) • Can result in sensitivity if individuals do not
understand the value in collecting these data • Can result in sensitivity if individuals do not
understand the value in collecting these data • Potential for valid and reliable measurement
over time if religious groups do not change
markedly • People with the same religious affi liation
may come from different countries or
have different ancestry or ethnocultural
backgrounds. • Self-assessed, i.e. individual declares
affi liation * The criteria include8 conceptual validity, measurement validity, exclusivity/exhaustiveness, meaningfulness, reliability, consistency and flexibility. Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia religion, lifestyle)
Profi ciency in English
Based on the individual’s self-
assessed ability to speak English
when the main language spoken
at home was a language other
than English
• Conceptually valid
• Can be exhaustive and exclusive
• Potential for great measurement bias –
meant to only represent spoken English
(not reading, writing or listening)
• Reliability/objectivity may be compromised
• May require discussion around why this
information was being collected (in terms of
meaningfulness to respondents)
Religious affi liation
Based on the individuals self-
identifi ed main religious belief or
the religious group to which they
belong
• Conceptually valid
• Potential for valid and reliable measurement
over time if religious groups do not change
markedly
• Self-assessed, i.e. individual declares
affi liation
• Can result in sensitivity if individuals do not
understand the value in collecting these data
• People with the same religious affi liation
may come from different countries or
have different ancestry or ethnocultural
backgrounds. ABS – Australian Bureau of Statistics; DIBP – Department for Immigration and Border Protection. * The criteria include8 conceptual validity, measurement validity, exclusivity/exhaustiveness, meaningfulness, reliability, consistency and flexibility. • People who speak the same language might
come from different countries or cultural and
social backgrounds etc. g
• Does not capture any information about
profi ciency in language of home country
(i.e. English) or other languages spoken in
the home. • Issues about classifying people with several
nationalities or people without passports
(e.g. some refugees) • Provides no information about ancestry or
ethnicity for Australian-born residents • Provides no information about cultural or
social differences (e.g. Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia To further explore which
additional data variables might be useful to accurately
represent ethnocultural identity, we used previously
established surveillance criteria8 to review commonly
used variables. As shown in Table 1, COB and LSH have
conceptual validity, objectivity and are relatively easy
to define. However, the inherent strengths of variables WPSAR Vol 5, No 2, 2014 | doi: 10.5365/wpsar.2014.5.1.011
2 www.wpro.who.int/wpsar Quinn et al Improving ethnocultural communicable diseases data in Australia Table 1. Advantages and disadvantages of collecting various ethnocul
surveillance7 criteria*
Variable/Description
Advantages
D
Country of birth
Based on the country where the
individual was born
• Relatively easy to defi ne and valid in
measurement
• Objective and exhaustive
• Reliable – categories related to specifi c
countries unlikely to change over time
• Denominator data available online through
ABS website
•
•
•
Main language spoken at home
Based on the main language
(other than English) spoken by
the individual in their home on a
regular basis
• Objective and conceptually valid
• Potential for consistency in assessment
• Can be exhaustive and exclusive
• Can help determine need for language or
interpreter services
• Denominator data available online through
ABS website
•
•
Country of nationality
Based on the individual’s
passport/citizenship
• Easy to defi ne and objective to measure
• Can be exhaustive and exclusive
• Reliable – categories of nationality unlikely to
change
• Conceptually valid
• Denominator data available online or upon
request from DIBP
•
•
•
Ethnicity/ancestry
Based on the individuals self-
perceived ethnic group – which
could be a country, region,
religious or cultural group, etc. Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia Eng
the hom
Country of nationality
Based on the individual’s
passport/citizenship
• Easy to defi ne and objective to measure
• Can be exhaustive and exclusive
• Reliable – categories of nationality unlikely to
change
• Conceptually valid
• Denominator data available online or upon
request from DIBP
• Issues a
national
(e.g. som
• Provides
ethnicity
• Provides
social di
Ethnicity/ancestry
Based on the individuals self-
perceived ethnic group – which
could be a country, region,
religious or cultural group, etc. • Allows respondents to self-identify their own
ethnicity based on whatever classifi cation
they see fi t
• Conceptually valid from the point of view of
the respondent
• Flexible for the respondent
• Denominator data available online through
ABS website
• Multiple
diffi cultie
• Self-rep
time
• May not
• More of
concept
• Questio
among r WPSAR Vol 5, N
www.wpro.who.int/wpsar
surveillance criteria*
Variable/Description
Advantages
Country of birth
Based on the country where the
individual was born
• Relatively easy to defi ne and valid in
measurement
• Objective and exhaustive
• Reliable – categories related to specifi c
countries unlikely to change over time
• Denominator data available online through
ABS website
Main language spoken at home
Based on the main language
(other than English) spoken by
the individual in their home on a
regular basis
• Objective and conceptually valid
• Potential for consistency in assessment
• Can be exhaustive and exclusive
• Can help determine need for language or
interpreter services
• Denominator data available online through
ABS website
Country of nationality
Based on the individual’s
passport/citizenship
• Easy to defi ne and objective to measure
• Can be exhaustive and exclusive
• Reliable – categories of nationality unlikely to
change
• Conceptually valid
• Denominator data available online or upon
request from DIBP
Ethnicity/ancestry
Based on the individuals self-
perceived ethnic group – which
could be a country, region,
religious or cultural group, etc. www.wpro.who.int/wpsar Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia • Allows respondents to self-identify their own
ethnicity based on whatever classifi cation
they see fi t
• Conceptually valid from the point of view of
the respondent
• Flexible for the respondent
• Denominator data available online through
ABS website
Length of stay in current country
Based on the length of time
(years) that the individual has
resided in their current country
from arrival
• Objective and conceptually valid
• Potential for reliability and consistency in
assessment
• Potential to distinguish between newly
arrived and long-term migrants
• Denominator data available online through
ABS website
• Year of arrival may be suffi cient here
Profi ciency in English
Based on the individual’s self-
assessed ability to speak English
when the main language spoken
at home was a language other
than English
• Conceptually valid
• Can be exhaustive and exclusive
Religious affi liation
Based on the individuals self-
identifi ed main religious belief or
the religious group to which they
belong
• Conceptually valid
• Potential for valid and reliable measurement
over time if religious groups do not change
markedly
• Self-assessed, i.e. individual declares
affi liation
ABS – Australian Bureau of Statistics; DIBP – Department for Immigration and Border Protection. * The criteria include8 conceptual validity, measurement validity, exclusivity/exhaustiveness, meaning surveillance criteria
Variable/Description
Advantages
Disadvantages
Country of birth
Based on the country where the
individual was born
• Relatively easy to defi ne and valid in
measurement
• Objective and exhaustive
• Reliable – categories related to specifi c
countries unlikely to change over time
• Denominator data available online through
ABS website
• Potential discrepancy between ‘nationality’
and ‘country of birth’
• Provides no information about cultural or
social differences
• Provides no information about the
ethnocultural group of Australian-born
residents
Main language spoken at home
Based on the main language
(other than English) spoken by
the individual in their home on a
regular basis
• Objective and conceptually valid
• Potential for consistency in assessment
• Can be exhaustive and exclusive
• Can help determine need for language or
interpreter services
• Denominator data available online through
ABS website
• People who speak the same language might
come from different countries or cultural and
social backgrounds etc. • Does not capture any information about
profi ciency in language of home country
(i.e. English) or other languages spoken in
the home. Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia Country of nationality
Based on the individual’s
passport/citizenship
• Easy to defi ne and objective to measure
• Can be exhaustive and exclusive
• Reliable – categories of nationality unlikely to
change
• Conceptually valid
• Denominator data available online or upon
request from DIBP
• Issues about classifying people with several
nationalities or people without passports
(e.g. some refugees)
• Provides no information about ancestry or
ethnicity for Australian-born residents
• Provides no information about cultural or
social differences (e.g. religion, lifestyle)
Ethnicity/ancestry
Based on the individuals self-
perceived ethnic group – which
could be a country, region,
religious or cultural group, etc. • Allows respondents to self-identify their own
ethnicity based on whatever classifi cation
they see fi t
• Conceptually valid from the point of view of
the respondent
• Flexible for the respondent
• Denominator data available online through
ABS website
• Multiple response categories may present
diffi culties for analysis
• Self-reported ethnicity may change over
time
• May not be exclusive
• More of a process than a static well-defi ned
concept
• Question may lead to offence, particularly
among refugees where racial, ethnic or
religious tensions exist in the community
Length of stay in current country
Based on the length of time
(years) that the individual has
resided in their current country
from arrival
• Objective and conceptually valid
• Potential for reliability and consistency in
assessment
• Potential to distinguish between newly
arrived and long-term migrants
• Denominator data available online through
ABS website
• Year of arrival may be suffi cient here
• May be sensitive for recently arrived
migrants/refugees and therefore may not be
asked consistently by surveillance staff
• May require discussion around why this
information was being collected (in terms of
meaningfulness to respondents)
• Provides no information about cultural or
social differences (e.g. Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia • Allows respondents to self-identify their own
ethnicity based on whatever classifi cation
they see fi t
• Conceptually valid from the point of view of
the respondent
• Flexible for the respondent
• Denominator data available online through
ABS website
•
•
•
•
•
Length of stay in current country
Based on the length of time
(years) that the individual has
resided in their current country
from arrival
• Objective and conceptually valid
• Potential for reliability and consistency in
assessment
• Potential to distinguish between newly
arrived and long-term migrants
• Denominator data available online through
ABS website
• Year of arrival may be suffi cient here
•
•
•
Profi ciency in English
Based on the individual’s self-
assessed ability to speak English
when the main language spoken
at home was a language other
than English
• Conceptually valid
• Can be exhaustive and exclusive
•
•
•
Religious affi liation
Based on the individuals self-
identifi ed main religious belief or
the religious group to which they
belong
• Conceptually valid
• Potential for valid and reliable measurement
over time if religious groups do not change
markedly
• Self-assessed, i.e. individual declares
affi liation
•
•
ABS – Australian Bureau of Statistics; DIBP – Department for Immigration and Border Protection. * The criteria include8 conceptual validity, measurement validity, exclusivity/exhaustiveness, meaningfulne Table 1. Advantages and disadvantages of collecting various ethnocultural data according to established
surveillance7 criteria* Table 1. Advantages and disadvantages of collecting various ethnocultural d
surveillance7 criteria*
Variable/Description
Advantages
Disadvant
Country of birth
Based on the country where the
individual was born
• Relatively easy to defi ne and valid in
measurement
• Objective and exhaustive
• Reliable – categories related to specifi c
countries unlikely to change over time
• Denominator data available online through
ABS website
• Potentia
and ‘cou
• Provides
social di
• Provides
ethnocu
resident
Main language spoken at home
Based on the main language
(other than English) spoken by
the individual in their home on a
regular basis
• Objective and conceptually valid
• Potential for consistency in assessment
• Can be exhaustive and exclusive
• Can help determine need for language or
interpreter services
• Denominator data available online through
ABS website
• People w
come fro
social ba
• Does no
profi cien
(i.e. 2. Phinney JS. Ethnic identity in adolescents and adults: review
of research. Psychological Bulletin, 1990, 108:499–514.
doi:10.1037/0033-2909.108.3.499 pmid:2270238 Funding None. 5. 2013
Perspectives
on
migrants. Catalog
no. 3416.0. Canberra, Australian Bureau of Statistics, 2013 (http://
www.abs.gov.au/ausstats/abs@.nsf/mf/3416.0,
accessed
19 September 2013). Acknowledgements The first author was employed as part of the New South
Wales Public Health Officer Training Programme, funded
by the New South Wales Ministry of Health. The study
was conducted while the trainee was on placement in the
Public Health Unit in Tamworth, Hunter New England
Population Health. 6. Najjar Z et al. Sustained outbreak of measles in Sydney, 2012: risk
for measles elimination in Australia. Western Pacific Surveillance
and Response Journal, 2014, 5(1):14–20. doi:10.5365/
wpsar.2013.4.4.001 7. Hess IM et al. A Salmonella Typhimurium 197 outbreak
linked to the consumption of lambs’ liver in Sydney, NSW. Epidemiology and Infection, 2008, 136:461–467. doi:10.1017/
S0950268807008813 pmid:17565766 8. Hahn RA, Stroup DF. Race and Ethnicity in Public Health
Surveillance: Criteria for the Scientific Use of Social Categories. CDC-ATSDR Workshop, 1994, 109(1):7–15. Improving ethnocultural communicable diseases data in Australia Quinn et al Confl icts of interest Confl icts of interest
None declared. 3. The guide: implementing the standards for statistics on cultural
and language diversity. Belconnen, Department of Immigration
and Multicultural Affairs, Diversity Management Section, 2001
(http://www.immi.gov.au/media/publications/pdf/guide.pdf,
accessed 25 April 2014). None declared. 4. National Hepatitis B Strategy 2010–2013. Canberra, Department
of Health and Ageing. 2010 (http://www.health.gov.au/internet/
main/publishing.nsf/Content/ohp-national-strategies-2010-
hepb/$File/hepb.pdf, accessed 5 January 2014). 1. Health of migrants: the way forward – report of a global
consultation, Madrid, Spain, 3–5 March 2010. Geneva, World
Health Organization, 2010 (http://www.iom.int/jahia/webdav/
shared/shared/mainsite/activities/health/promotion/Health-of-
Migrants.pdf, accessed 25 April 2014). Box 1. Ethno-cultural
data
collected
in
routine
notifiable diseases surveillance in Australia WPSAR Vol 5, No 2, 2014 | doi: 10.5365/wpsar.2014.5.1.011
3 www.wpro.who.int/wpsar Improving ethnocultural communicable diseases data in Australia www.wpro.who.int/wpsar References: 1. Health of migrants: the way forward – report of a global
consultation, Madrid, Spain, 3–5 March 2010. Geneva, World
Health Organization, 2010 (http://www.iom.int/jahia/webdav/
shared/shared/mainsite/activities/health/promotion/Health-of-
Migrants.pdf, accessed 25 April 2014). 1. Health of migrants: the way forward – report of a global
consultation, Madrid, Spain, 3–5 March 2010. Geneva, World
Health Organization, 2010 (http://www.iom.int/jahia/webdav/
shared/shared/mainsite/activities/health/promotion/Health-of-
Migrants.pdf, accessed 25 April 2014). 9. Gushulak BD, MacPherson DW. The basic principles of
migration health: population mobility and gaps in disease
prevalence. Emerging Themes in Epidemiology, 2006, 3:3. doi:10.1186/1742-7622-3-3 pmid:16674820 10. Australian Standard Classification of Cultural and Ethnic Groups
(ASCCEG). [1249.0]. Canberra, Australian Bureau of Statistics,
2011
(http://www.abs.gov.au/ausstats/abs@.nsf/mf/1249.0,
accessed 19 September 2013). WPSAR Vol 5, No 2, 2014 | doi: 10.5365/wpsar.2014.5.1.011
4 www.wpro.who.int/wpsar
|
https://openalex.org/W1577461677
|
http://periodicos.unb.br/index.php/linhascriticas/article/download/3364/3051, https://www.redalyc.org/pdf/1935/193517364007.pdf
|
es
|
Las tecnologías aplicadas a la educación especial integradora: la contribución del software educativo "Hércules y jiló"
|
Linhas Críticas/Linhas críticas
| 1,969
|
cc-by
| 9,721
|
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 131
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
LAS TECNOLOGÍAS APLICADAS A LA EDUCACIÓN
ESPECIAL INTEGRADORA: LA CONTRIBUCIÓN
DEL SOFTWARE EDUCATIVO “HÉRCULES Y JILÓ”
AS TECNOLOGIAS APLICADAS À EDUCAÇÃO ESPECIAL
INTEGRADORA: A CONTRIBUIÇÃO DO SOFTWARE
EDUCATIVO “HÉRCULES E JILÓ”
THE TECHNOLOGIES OF INFORMATION AND COMMUNICATION
APPLIED TO INTEGRATING SPECIAL EDUCATION: THE CONTRIBUTION
OF THE EDUCATIONAL SOFTWARE “HÉRCULES AND JILÓ”
LES TECHNOLOGIES DE L’INFORMATION ET DE LA
COMMUNICATION APPLIQUÉES À L’ÉDUCATION SPÉCIALE
INTÉGRATIVE : LE LOGICIEL ÉDUCATIF “HÉRCULES ET JILÓ”
Catalina Maria Alonso *
Amaralina Miranda e Souza **
RESUMEN
Las Tecnologías de la Información y de la Comunicación resultan grandes aliadas del profesor
para favorecer el proceso de enseñanza-aprendizaje, ya que posibilitan atender a diferentes
formas de aprender y considerar las diferencias individuales de alumnos y profesores. El énfasis
se debe dar a la adecuación de los medios utilizados para poder alcanzar los objetivos de aprendizaje,
respetando las condiciones de respuesta de los alumnos y la metodología del profesor. Presentamos
las líneas fundamentales que han servido de base en el diseño, la elaboración y aplicación del
software educativo "Hércules y Jiló", recomendado para el trabajo pedagógico con alumnos que
presentan necesidades educativas especiales. En este proceso se han abordado varias líneas de
acción: 1. fundamentar su realización con una base científica y tecnológica, para lograr una relación
y motivación amigable del alumno con la máquina; 2. ofrecer una base científico-pedagógicametodológica para intentar alcanzar un atractivo tal que el alumno pueda construir conocimiento a
través de su interacción con el software y sus actividades derivadas. Se aspira a que las tecnologías,
y en particular el software educativo, puedan contribuir a posibilitar el aprendizaje de todos los
alumnos, que presenten o no necesidades educativas especiales.
Palabras-clave:Tecnologías de la información y de la comunicación. Software educativo. Educación especial.
*
Profesora Doctora del Departamento de Didáctica Org. Escolar y DD EE – Facultad de Educación – Universidad
Nacional de Educación a Distancia – UNED, Madrid – España. Investigadora premiada en el área de Estilos
de Aprendizaje, Informática Educativa con varias publicaciones en estas áreas (calonso@edu.uned.es).
** Profesora Doctora del Departamento de Teoría e Fundamentos – Área de Educación Especial – Facultad
de Educación –Universidade de Brasilia – Brasil. Investigadora en el área de Informática Aplicada a la
Educación Especial / Inclusiva. Texto escrito a partir de mi Tesis Doctoral, dirigida por la profesora
Catalina Maria Alonso, aprobada, Cum Laude, en la Facultad de Educación de la Universidad Nacional de
Educación a Distancia – UNED – Madrid, día 20 de noviembre de 2006 (amara@unb.br).
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
131
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 132
C. M. Alonso, A. M. Souza
INTRODUCCIÓN
Actualmente, vivimos en un mundo globalizado, que está en constante transformación, donde cada día se crean nuevos recursos tecnológicos cada vez más desarrollados
y modernos.
Al hacer hincapié en el hecho de que la escuela no puede existir sin una conexión
con el mundo, el profesor no puede ignorar los recursos tecnológicos existentes, sino
enriquecer su práctica utilizándolos en el proceso de enseñanza-aprendizaje, pues educar
es desarrollar, lo más plenamente posible, todas las potencialidades intelectuales, afectivas,
creativas (artísticas) y morales del individuo.
La tecnología mediática revolucionó el mundo de las comunicaciones y de las informaciones. Sin darnos cuenta, adaptamos nuestra forma de actuar, de pensar y de comunicarnos, por la integración de esos nuevos medios, a nuestros comportamientos. Dentro
de este contexto, las alteraciones provocadas por las intermediaciones tecnológicas son
innumerables: desde el teléfono al fax; del teléfono móvil al correo electrónico; de la
televisión vía satélite a la internet. Vivimos otro estilo de vida y no siempre conseguimos
darnos cuenta de ello.
El profesor necesita ejecutar su capacidad de improvisación de administrar situaciones
inesperadas que exigen habilidad, creatividad y eficacia, a fin de que su intervención sea
operante y eficiente, ya que como docente tiene un importante papel dentro del proceso
de integrar los recursos tecnológicos en clase. La intervención del profesor es necesaria
pues los medios de comunicación, por si solos, la mayoría de las veces, no consiguen una
interacción entre el conocimiento propuesto y el nuevo saber.
Las tecnologías utilizadas en la educación constituyen, hoy día, un instrumento de
enorme potencial para el enriquecimiento curricular y para una mejora de la calidad de
la enseñanza.
La televisión, el vídeo, la radio y el ordenador constituyen importantes instrumentos
pedagógicos auxiliares, sin que deban sustituir, por ello, las relaciones de comunicación
e interacción directa entre el educador y el educando.
Una de las contribuciones de las tecnologías es la de favorecer el trabajo del profesor,
enriqueciendo y diversificando su forma de conducir el proceso de enseñanza y de aprendizaje. Es necesario observar la complejidad de ese proceso, escogiendo como foco de
análisis la producción y evaluación de materiales pedagógicos para ambientes de aprendizaje, enriquecidos por el uso de las nuevas tecnologías.
EL PROFESOR Y LA MEDIACIÓN CON LAS TECNOLOGÍAS EN EL AULA
La educación tecnológica promueve el despertar para la interpretación del contexto
social actual a la luz de sus condicionamientos y fundamentos. Por eso es importante
verificar cuestiones relativas a los valores del momento actual, haciendo especial hincapié
en la dimensión ética en un mundo repleto de tecnología en todos los sectores.
Estas reflexiones nos remiten a la interpretación del mundo desde las Tecnologías de
la Información y de la Comunicación, con el propósito de construir una educación
132
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 133
Las tecnologías aplicadas a la educación especial integradora
transformadora que vaya más allá del espacio escolar, pues de todos es sabido que en los
días actuales debemos integrar las dimensiones del saber-hacer al saber-ser. Para ello,
necesitamos comprender y creer en una educación crítica que pueda estar atenta a los
fundamentos teóricos del conocimiento y a la práctica social. Educación es esa mezcla de
responsabilidad y de mucha esperanza en la posibilidad de transformaciones en la
sociedad (GRINSPUN, 1999, p. 64).
La integración de las innovaciones tecnológicas a los procesos educativos dependerá
de la concepción de la educación presente en las nuevas generaciones, que fundamenta
las acciones y políticas del sector. Si creemos que la educación es un medio de emancipación
(y no solamente un instrumento de dominación y reproducción de las desigualdades
sociales), tendremos que defender una integración creativa, y no simplemente relativa
al mercado, de estas tecnologías de comunicación que tanto nos preocupan como educadores, y nos solicitan como ciudadanos y consumidores.
En la actualidad es necesario que la escuela desarrolle una educación que consiga
atender a los nuevos procedimientos de información y comunicación, propiciándoles a
los alumnos medios apropiados para la construcción de sus conocimientos, sin olvidar
su formación en términos de sentir y crear.
El gran desafío es la transformación de profesores capaces de tratar con alumnos
algunas veces en situaciones extremas: con los alumnos que ya poseen conocimientos
tecnológicamente avanzados y acceso pleno al universo de informaciones disponibles en
los múltiples espacios virtuales; con los alumnos que se encuentran en plena exclusión
tecnológica sin oportunidades para vivir y aprender en esta nueva realidad; y con las
instituciones de enseñanza equipadas precariamente y con recursos mínimos para poder
desarrollar su trabajo.
El ordenador en el aula permite al profesor atender a la diversidad de sus alumnos
de forma individualizada, además de promover actividades colectivas que favorezcan la
cooperación entre ellos, resultando una práctica inclusiva e integradora, donde todos
estarán actuando y aprendiendo entre ellos.
Para que se puedan realizar esas y otras transformaciones esperadas en la enseñanza,
es necesario que el profesor sepa tratar críticamente las tecnologías contemporáneas de
información y comunicación y que sepa utilizarlas pedagógicamente. El profesor debe
conocer el ordenador, los soportes mediáticos y todas sus posibilidades educativas e interactivas de las redes y espacios virtuales para aprovecharlas en las más diversas situaciones
de aprendizaje y en las más variadas realidades educativas.
Se debe trabajar satisfactoriamente con el conocimiento ya adquirido y a la búsqueda
de nuevas informaciones, con los cambios estructurales de los saberes en todas las áreas,
con una investigación permanente. Y también asumir una postura de inquisición, crítica y
duda ante las informaciones – recientes y viejas – y, al mismo tiempo, ejercer el papel de
orientación y cooperación con los alumnos. Enseñarlos a aprender, y aprender enseñando.
El profesor necesita del uso de diferentes lenguajes para sobrevivir en el mundo del
trabajo actual. Múltiples lenguajes, que van desde la influencia tecnológica al dominio de
idiomas, para que pueda salir del cerco de la clase y del ambiente escolar para conectarse,
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
133
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 134
C. M. Alonso, A. M. Souza
junto a sus alumnos, con todo el mundo, promover las relaciones institucionales con otros
profesores, de otras escuelas o países, con distintas culturas y realidades sociales. El principal
valor, la autoestima como profesor, esto es, ser profesor con orgullo y por opción.
Además, el profesor, debe identificarse con su función, con su estilo y con su propia
profesión. El profesor debe tener capacidad de liderar y cooperar, de respetar las diferencias,
de participar, de atreverse, de ir más allá, de aceptar desafíos y buscar su permanente
actualización, poseer autonomía para enseñar y para aprender y, especialmente, para
ser profesor, conocerse como persona y ser consciente de sus límites y avances.
Todos estos comportamientos desafiantes, provenientes de la integración de las
nuevas tecnologías digitales al ambiente educativo, imponen cambios estructurales a la
acción docente y a las formas de enseñanza. Se exigen nuevas posturas que posibiliten a
los profesores la soltura metodológica adecuada para realizar una enseñanza de calidad,
aunque las propias concepciones de lo que representa la enseñanza y de lo que es el
aprendizaje se hayan transformado.
Ante todo, es necesario que exista cierta transparencia y claridad sobre las reales
posibilidades de acción del docente con el uso de las tecnologías. Una educación crítica
sobre los medios de comunicación, retirándoles el aura de “cajas-negras”, objetos mágicos
poderosos y temidos, situándolos en sus debidos lugares, como equipos, herramientas y
espacios – en este caso, educativos – que pueden revolucionar la enseñanza y auxiliar a
los profesores y alumnos a enseñar y a aprender.
Este profesor que circula libremente en el medio digital encuentra allí un espacio
educativo radicalmente diferente. Comprende que su acción docente en este nuevo
ambiente apenas requiere un cambio metodológico, sino un cambio de percepción de lo
que es enseñar y aprender. Objetos multimedia digitalizados – sonidos, imágenes y texto –
pueden ser creados, editados, integrados y transmitidos con gran facilidad. Instructores
y estudiantes pueden controlar sus presentaciones y análisis con un poco más de experiencia
en ordenadores, más allá de las posibilidades del uso del teclado y del ratón.
Las posibilidades interactivas del ambiente digital involucran a estudiantes y profesores
en el aprendizaje. El aprendiz puede llegar a tener mayor responsabilidad por conducir
el proceso educativo y aprender a utilizar herramientas, entre otras, procesadores de textos,
planillas, que serán útiles en el mundo real.
Por medio de la tecnología se pueden realizar actividades integradas y potenciar la
búsqueda de informaciones sobre lo cotidiano, que ayuden a la aprehensión del conocimiento científico, siempre que el profesor sepa articular teoría y práctica. En realidad,
esa cuestión es el motivo de preocupación cuando se conoce que muchas escuelas aún no
reúnen las mínimas condiciones de infraestructura para la realización de sus actividades
en la enseñanza. Sin embargo, se observa que los espacios de investigación en las escuelas
se han visto multiplicados, a medida que los profesores recurren a la creatividad para
acceder a las informaciones, bien de forma directa o indirecta.
Por ello, podemos servirnos de las tecnologías y de los medios de comunicación para
incrementar el trabajo realizado en clase, pues una de las grandes preocupaciones que
ronda actualmente el campo educacional es la reducción de la distancia entre el mundo
134
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 135
Las tecnologías aplicadas a la educación especial integradora
real y el mundo virtual. La escuela es responsable de conseguir un aprendizaje articulado
con lo cotidiano, permitiendo una enseñanza con un mínimo de condiciones que
favorezca el entusiasmo y el interés en la búsqueda del conocimiento científico.
EL PROFESOR FACILITADOR EN LA
CONSTRUCCIÓN DEL CONOCIMIENTO
A partir del principio de que el alumno debe participar activamente en la producción
del conocimiento, no podemos olvidarnos que hoy tenemos como aliados del trabajo
escolar una inmensa cantidad de materiales tecnológicos que, a su vez, permiten que el
alumno haga, construya y organice su propio saber.
Preocupados por permitir que el alumno haga y construya, el profesor debe repensar
una nueva didáctica y diseñar un nuevo tipo de aprendizaje, con el propósito de favorecer
al alumno en la búsqueda del conocimiento. En este mundo actual, se observa que el
avance tecnológico en los medios de información y comunicación funciona a ritmo
acelerado. Nos encontramos, entonces, ante una situación “sui generis” en lo referente a
los aspectos didáctico-pedagógicos.
La búsqueda de esa nueva didáctica implica particularmente una reflexión sobre
el compromiso en relación con el abordaje diversificado en la construcción del
conocimiento, requiriendo una nueva interpretación de la unicidad teoría-práctica en el
aspecto pedagógico. Dicha unicidad, a su vez, demanda transformar los elementos didácticopedagógicos: contenido / método, relación profesor / alumnos, planeamiento / ejecución,
fines / evaluación (ALONSO, 2001).
Para ello, es necesario reflexionar sobre el papel del profesor. Como mediador,
orientador o facilitador; el profesor siempre es motivo de discusión en lo referente a las
formas de organización innovadoras del proceso pedagógico, principalmente cuando se
le atribuye a la escuela la característica de un espacio autónomo, cuya configuración y
funcionamiento tienen como elemento decisivo la acción e interacción de los diferentes
actores (profesores, dirigentes, funcionarios, alumnos y padres).
En un ambiente de estudio con disponibilidad de recursos tecnológicos, ya sea
informatizado o no, el profesor debe proporcionar condiciones para un aprendizaje
significativo, promoviendo la construcción del conocimiento, a través de la reinvención.
Para que el alumno pueda construir el conocimiento es necesario propiciar ambientes
que lo desafíen y lo motiven para la exploración, reflexión, depuración y descubrimiento
de ideas. Y el profesor debe ser creativo, buscar alternativas entre los recursos tecnológicos
disponibles y ofrecer al alumno el soporte necesario para ayudarle en el procesamiento
de informaciones. Asimismo, al docente le corresponde valorar la iniciativa del alumno,
interviniendo en actividades que no sean meras secuencias sistematizadas ni tampoco
simples experimentos espontáneos. En esos ambientes, las actividades se desarrollan
alrededor de proyectos y no se atienen a contenidos específicos previamente establecidos.
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
135
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 136
C. M. Alonso, A. M. Souza
La utilización de los recursos computacionales debe alertar al docente de que, para
un aprendizaje significativo, el alumno debe ser el sujeto de su propia acción, participar
activamente en un proceso continuo de colaboración, motivación, investigación, reflexión,
ganando autonomía e independencia.
Las herramientas tecnológicas no auxilian sólo en la articulación entre el conocimiento
y la mente, promoviendo movimientos sociales, culturales e intelectuales, sino también
contribuyendo para el aprendizaje significativo sobre el tema propuesto. Por ello, el foco
central de los estudios de Papert (1981, 1995) no es la máquina, sino la mente. El aprendizaje del alumno sólo se produce cuando actúa sobre los contenidos específicos y en la
medida en que posee estructuras propias, previamente construidas o en construcción
(ALMEIDA, 2001, p. 61).
Para Papert (1995), es necesaria una metodología que nos permita permanecer cerca
de situaciones concretas, pues el hacer y el comprender están vinculados a los problemas
con los que el individuo se enfrenta en su realidad física o social. Esa idea se aproxima
a la teoría de Vigotski (1994), según la cual el aprendizaje se encuentra en el desarrollo
histórico-social del sujeto.
En el contexto de la práctica pedagógica cotidiana, el ordenador podrá ser utilizado
por el profesor como un importante instrumento pedagógico. Sabiendo explorar esa
herramienta y trabajar con proyectos que surgirán en clase, el educador podrá proporcionar un aprendizaje en este enfoque, contextualizado y significativo. Sin embargo, el
uso del ordenador no podrá ser privado de las relaciones humanas, ya que la construcción
del saber depende, sobre todo, de la interacción profesor-alumno-ordenador, pues el
profesor es pieza clave en el desarrollo de las habilidades, el lado afectivo y los valores
de cada alumno.
Al hablar sobre el uso de tecnologías como recursos didácticos, es importante recordar
el proceso de interacciones entre el profesor y los alumnos, puesto que este proceso [...]
contribuye, con naturalidad, a la construcción del conocimiento, pues debe suceder con
amplia participación del alumno que utiliza sus experiencias sociales y de vida como autor de
sus propios caminos (SILVA, 2004, p. 245). Entre esas interacciones, destacamos el hecho
del profesor actuando como mediador además de trabajar con actividades lúdicas. Todos
estos aspectos facilitan una mayor aproximación entre alumno y profesor, pues éste es un
camino de doble dirección: un proceso de intercambios que favorece en el profesor
aprender con el alumno, aprender y enseñar, enseñar y aprender.
A ese respecto, Lévy (2001, p. 30) nos recuerda que:
[...] la escuela debe convertirse en un lugar de inteligencia colectiva, de cooperación, de
apertura, de discusión entre las asignaturas y especialidades, de circulación de las personas
y de los saberes. Ella debe recompensar la originalidad, la curiosidad, lo desconocido. Sólo
se aprende aquello que se practica, lo que es ejercitado con frecuencia, lo que está integrado
en los reflejos.
136
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 137
Las tecnologías aplicadas a la educación especial integradora
LA INFORMÁTICA EDUCATIVA Y LA ATENCIÓN A LA DIVERSIDAD
El ordenador resulta un instrumento utilizable por su “multi-funcionalidad”, para
realizar varias tareas, lo que ofrece nuevas posibilidades permitiendo que la misma
máquina sea utilizada para fines y actividades diferentes. Esa multifuncionalidad
también facilita atender a las diferencias individuales de los usuarios. Así, el ordenador
puede ser ajustado a las características y necesidades de las personas.
En el ámbito escolar, el uso pedagógico del ordenador se considera como un factor
de avance cualitativo del proceso enseñanza-aprendizaje.
Además, existe la idea central de que la informática educativa puede volverse un
poderoso aliado del profesor en el proceso de facilitar la construcción del conocimiento;
el profesor puede servirse de ella para crear situaciones de aprendizaje bastante motivadoras
y productivas. La introducción del ordenador en nuestras escuelas, por ejemplo, está
planteando nuevas formas de trabajo por tratarse de un medio que puede ser utilizado
como recurso educativo muy poderoso y versátil.
Según Valente (1991, p. 29) el uso del ordenador en el aula, como medio educativo,
ha cuestionado los métodos y procesos de enseñanza utilizados, y ha posibilitado entender
que el profesor puede ejercer otras funciones, además del mero papel de transmisor
del conocimiento. También puede facilitar el aprendizaje, algo que con el ordenador se
consigue también.
Sin duda existe una crítica al uso del ordenador simplemente como el de una
herramienta de ejecución de programas automatizados que sirve a objetivos muy
limitados y no permite al alumno realizar un aprendizaje más profundo. Aquellos
que defienden la idea de introducir en su programa el uso del ordenador como parte del
currículum, recomiendan lenguajes más simples, de forma que el ordenador funcione
como un recurso, un medio con el cual el alumno desarrolle su aprendizaje en algunos
aspectos más complejos.
Es decir, el ordenador como herramienta presenta ciertas características que resultan
de gran contribución, especialmente al ser utilizado como recurso educativo (ESPAÑA,
1992), porque:
• Se trata de un medio motivador para el niño y posibilita incluir en los programas
música, colores, animación. Así se convierte en material con atractivos que contribuyen
a centrar la atención.
• Tiene una gran capacidad de memoria, pudiendo almacenar un amplísimo número
de datos y permite una cierta rapidez en la ejecución de las tareas.
• Presenta una gran versatilidad, permitiendo ser utilizado en muy distintos ámbitos y
con finalidades muy diversas, lo que responde a la filosofía de seleccionar materiales
que puedan ser adaptables a las distintas necesidades de los alumnos.
• Puede ser una herramienta con gran potencial para reforzar estrategias de resolución
de problemas ofreciendo distintas oportunidades para resolverlos, haciendo más hincapié
en los éxitos que en los fracasos, lo que puede ayudar a disminuir la frustración ante
el error.
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
137
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 138
C. M. Alonso, A. M. Souza
• Posibilita plantear situaciones de trabajo de grupo, con programas que admiten
interacción de varios niños, dando lugar a situaciones de trabajo cooperativo y
diálogo espontáneo que influyen positivamente en el proceso de socialización.
• Se adapta a las peculiaridades de cada alumno, respetando su ritmo de aprendizaje.
En este caso el ordenador se caracteriza, entre otras cosas, por tener una paciencia
infinita, pudiendo repetir una tarea tantas veces como el usuario desee y ejecutando
sólo aquello que se ha pedido, sin tomar ninguna decisión por su cuenta.
Además de como herramienta, el ordenador puede ser adaptado a los diferentes estilos
de aprender, a los diferentes niveles de capacidad e interés intelectual, a las diferentes
situaciones de enseñanza – aprendizaje, posibilita crear nuevas maneras de enseñar que
puede implicar cambios que quizá el sistema escolar aún no esté preparado para realizar
con flexibilidad. Por todo esto hay que determinar cómo podemos incorporar el ordenador
como una herramienta potencialmente útil, de manera que se integre en el aula, en el
currículum y que permita al profesor ajustar su trabajo en la clase para ofrecer al alumno
diversas posibilidades de respuestas educativas cada vez más positivas.
LA INFORMÁTICA EDUCATIVA APLICADA A LA
EDUCACIÓN ESPECIAL INTEGRADORA/ INCLUSIVA
El descubrimiento de nuevas formas de enseñar y aprender por medio de la informática
educativa es un desafío extremamente motivador, que implica y que demanda trabajos
de investigación dirigidos a la producción de medios y materiales que posibiliten también
la teoría respecto de su aplicación en la relación mediada por esta tecnología.
Existen varias investigaciones que revelan que la informática tiene potencial para
dinamizar el proceso enseñanza–aprendizaje. En particular el software educativo, cuando
es adecuadamente empleado, establece relaciones cualitativamente diferentes y puede
funcionar como instrumento de liberación de la situación pedagógica, proporcionando
un espacio de libre descubrimiento, aprendizaje constructivista, para realimentar y redimensionar la práctica pedagógica del profesor para hacerla más significativa (SANTOS,
2000).
Se destaca también que la atracción ejercida sobre los alumnos al usar el ordenador,
la rapidez en la realización de las tareas, el respeto al ritmo de aprendizaje del alumno, la
diversificación de las rutas que llevan a la resolución de problemas, la posibilidad de
trabajo colectivo, entre otros aspectos, hacen pensar en las ventajas que se pueden obtener
con el uso correcto del ordenador para objetivos educacionales.
Martí (1992), citado por Pérez (2003, p. 431), comenta algunos inconvenientes en
el uso de la informática con los alumnos con discapacidad, sobre todo por la rapidez de
su evolución que puede dejar obsoletos algunos productos, sin olvidar que, en general,
son muy pocos los programas elaborados para atender a las singularidades de los alumnos
con necesidades educativas especiales. No obstante considera que, pese a todo, el empleo
de la informática para los alumnos con discapacidad es de gran utilidad porque puede
contemplar algunos aspectos que consigue el ordenador, entre los que destaca:
138
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 139
Las tecnologías aplicadas a la educación especial integradora
• Posibilita una mejora en las capacidades de comunicación, con un mejor control
sobre su entorno, y potencia la autonomía;
• Ayuda a mantener el interés para continuar realizando la actividad propuesta porque
con el ordenador la persona con discapacidad domina más el entorno, además
aumenta la autoestima porque al acceder a actividades más complejas, que hasta
ahora no podía realizar, aumenta la confianza en sí misma e incentiva a seguir en
búsqueda de otros aprendizajes;
• Permite aprender estrategias cognitivas adecuadas para solucionar problemas, de
manera que consiga tener un mayor control sobre el propio entorno del aprendizaje.
Especialmente importante para los alumnos que presentan deficiencia intelectual,
cuyas habilidades meta-cognitivas están claramente afectadas.
López (1995, p. 582) atribuye a la aplicación de las tecnologías en la Educación
Especial, específicamente con los medios informáticos, muchas ventajas:
• La versatilidad y flexibilidad que permiten múltiples aplicaciones con objetivos diversos
y adaptaciones en casos particulares.
• Facilidad de individualización de la enseñanza, adecuando las tareas al nivel de
competencias del alumnado y de acuerdo con su propio ritmo de aprendizaje.
• Posibilidad de repetición del ejercicio y la auto-corrección, al poder comprobar los
resultados de inmediato.
• Aumenta el grado de autonomía e independencia personal y permite al profesor
disponer de más tiempo de dedicación a otros alumnos que lo necesiten más.
En este sentido, existen datos de que trabajos realizados con los alumnos con necesidades especiales muestran que el ordenador puede ayudarles a adquirir aprendizajes
importantes, posibilitándoles a enriquecer sus capacidades intelectuales, su sentido de
autoestima para, de manera independiente, explorar y ejercitar sus propias acciones.
Por otra parte, es grande el desafío al intentar crear ambientes de aprendizaje con la
perspectiva de construcción de conocimientos utilizando el ordenador. Esto implica
considerar los cambios de comprensión acerca del ordenador como una forma de representar el conocimiento: el significado de enseñar y aprender y el papel del profesor en
este nuevo contexto (VALENTE, 2001).
EL SOFTWARE EDUCATIVO COMO RECURSO DIDÁCTICO
PEDAGÓGICO DE APOYO AL PROCESO ENSEÑANZA-APRENDIZAJE
El uso de la informática en la educación exige un esfuerzo constante por parte de los
educadores para transformar la simple utilización del ordenador en un abordaje educacional
que favorezca efectivamente el proceso de adquisición de conocimiento por el alumno.
Para Valente (1991, p. 18), una de las cuestiones fundamentales en el desarrollo de
software educativo es el aspecto pedagógico: qué es lo que el software se propone enseñar
y cómo esto es realizado.
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
139
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 140
C. M. Alonso, A. M. Souza
Lo que caracteriza un software como educativo es su inserción en el contexto de
enseñanza-aprendizaje, el hecho de ser desarrollado con la finalidad de llevar al alumno
a construir determinado conocimiento relativo a un contenido didáctico.
En este contexto, el software educativo para la educación mediada por el ordenador
tiene la importante función de permitir que el alumno se sirva de él para interactuar
cognitivamente con el contenido disponible, construyendo nuevos conocimientos e
instrumentos para transferirlos en otras situaciones, en su medio y en su vida cotidiana.
En el lenguaje LOGO, por ejemplo, el proceso de creación es más importante que el
producto en sí. Además, el uso del lenguaje, en la forma expuesta por su autor, permite
la caracterización y el seguimiento de los esquemas con los cuales el niño actúa en cada
momento, lo que favorece conocer sus procesos cognitivos y por lo tanto un trabajo
pedagógico a la altura de su zona de desarrollo proximal, descrita por Vigotski (2000).
Como en todo proceso de enseñanza aprendizaje, el papel del profesor en la mediación
de las actividades de los alumnos es esencial e implica la creación de ambientes de
aprendizaje creativos y motivadores.
Muchas veces la rutina de clase y las dificultades de los alumnos pueden hacer que el
profesor no perciba que determinado alumno no sigue el ritmo de su grupo y evidencia
bajo rendimiento escolar. Ante el ordenador, con una propuesta y un ambiente de aprendizaje diferente, el alumno “olvida”, “se relaja” y puede revelar los conocimientos que
realmente ya construyó.
O aún, otros niños de los que se preocupan los profesores, porque piensan que
no aprenden nada, porque su vínculo con el aprendizaje formal está mal, parece que sí
funcionan en un nivel cognitivo inferior al esperado para su grupo y, muchas veces,
pueden revelar sus reales adquisiciones en las propuestas surgidas en el ambiente multimedia con el ordenador.
Para que estas situaciones puedan suceder, es necesario construir un puente entre
las actividades curriculares y el uso del ordenador, integrando todo el trabajo, y
concediéndole al niño con dificultades una mejor relación con el medio en el que vive,
la oportunidad de auto-conocimiento. Esa vivencia despierta en el alumno la oportunidad
de reflejar su desarrollo, y su seguridad ante situaciones desconocidas, además de llevarlo
a reflexionar sobre su propio pensamiento (meta-cognición).
La meta-cognición permite que las diferencias individuales tengan relevancia en consideración al desarrollo cognitivo y en relación a la enseñanza y al aprendizaje (TARDIF,
1992).
Podemos observar que el uso del ordenador despierta la motivación en la mayoría de
los alumnos y que esto puede ser una buena oportunidad para que el profesor rescate
al alumno que no va bien en clase, y que pueda funcionar como un instrumento que
permita una interacción alumno-objeto, alumno-alumno, y alumno-profesor, basado en
los desafíos e intercambios de experiencias.
El profesor necesita plantear situaciones educacionales que promuevan el aprendizaje,
llevando a los alumnos a la exposición de sus conocimientos y dudas, a llenar los
140
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 141
Las tecnologías aplicadas a la educación especial integradora
espacios vacíos, a apropiarse de nuevos conocimientos. También es necesario orientar la
interacción social por medio de reglas claras y bien definidas, organizadas, integrando
y presentando los conocimientos, proponiendo actividades, ayudando a los alumnos a
superar las dificultades que aparecerán a lo largo del saber (SCOZ, 1994).
Entre las variadas características que podemos citar para el software educativo existe
una que, sin duda, refleja todo el esfuerzo de los elaboradores del material didáctico
y que cumple los objetivos del sistema educativo: la transferencia de los conocimientos
disponibles en el material didáctico a otras situaciones distanciadas de la relación educativa
propiamente dicha.
En la literatura pedagógica la transferencia de los aprendizajes ocupa un lugar destacado.
Varios pedagogos e investigadores discuten sobre las modalidades de enseñanza
que mejor pueden favorecer la transferencia de conocimientos, y destacan que la escuela
contemporánea aún no ha conseguido integrar estos mecanismos.
En el contexto de la educación especial, el concepto de transferencia de conocimiento
es fundamental porque se adapta a las propias características de los alumnos con necesidades educativas especiales. El software educativo necesita estar orientado para que el
alumno interactúe con el conocimiento que articula, y lo instrumentalice para reaplicar
algunas situaciones en otras distintas, modificando su práctica, reafirmando su pertinencia
y apoyándose definitivamente en su memoria a largo plazo.
Al mismo tiempo que facilita la comunicación entre el profesor y el alumno, el software
educativo organiza las actividades de aprendizaje, de tal forma que las intervenciones del
profesor se concretan en las acciones del alumno. Esto sucede porque, de una forma o
de otra, su elaborador presenta una representación particular del conocimiento deseado.
La creación de un espacio libre para la interactividad cognitiva debe ser otra característica importante del software educativo. No obstante, aunque el alumno se distancie
del proyecto comunicativo proporcionado por el software, el material didáctico tiene
siempre que ofrecer espacio para que la interactividad sea potenciada al máximo, o sea,
para que el alumno integre los contenidos propuestos y haga de ellos un proyecto de
formación, llegando a extrapolar esos logros para avanzar en dirección complementaria
o de profundización.
Por otra parte, se observa que la mayoría del software desarrollado para la educación
especial parte del principio de que los niños con necesidades educativas especiales tienen
baja capacidad para aprender y, por lo tanto, las actividades están niveladas con esa
capacidad, y la pedagogía adoptada enfatiza la repetición de actividades poco complejas
(SOUZA, 2005).
Se puede decir, además, que en el centro de estas dificultades están las dificultades
del sistema educativo, principalmente en la escuela y en la precaria formación del profesor
para actuar con la informática educativa, específicamente para integrar el ordenador
como apoyo para el desarrollo de sus actividades con el alumno en clase.
Para Torres (1990), el ordenador también ofrece ventajas para trabajar con niños que
presentan necesidades educativas especiales, porque ahorra tiempo y esfuerzo; introduce
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
141
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 142
C. M. Alonso, A. M. Souza
una dinámica visual importante; incrementa la motivación y refuerza la atención;
prepara al alumno para el aprendizaje permanente y autónomo; contribuye a las capacidades de autoaprendizaje estimulando la creatividad; ofrece la posibilidad de una
evaluación dinámica continua y objetiva; contribuye a la adquisición de capacidades
básicas como son la lectura y escritura, la expresión de cálculo, el pensamiento lógico
y la resolución de problemas.
Además, el uso del ordenador en clase puede ayudar al profesor a: organizar mejor
su actividad educativa, evaluar permanentemente la situación del niño registrando
los cambios producidos, observar el grado de aprendizaje de cada uno de los alumnos,
identificar las diferencias y las necesidades para introducir nuevas estrategias que faciliten
el proceso de aprendizaje.
El profesor puede sacar provecho del software educativo para comprender, criticar
y hasta concebir su propio material didáctico, a partir del cual podrá obtener el avance
cualitativo de su enseñanza, obteniendo provecho de las variadas posibilidades ofrecidas
por la informática educativa.
LA ENSEÑANZA Y EL APRENDIZAJE DEL ALUMNO CON NECESIDADES
EDUCATIVAS ESPECIALES MEDIADOS POR EL ORDENADOR
El aprendizaje mediado es un proceso interactivo a través del cual el profesor potencia
la interiorización de los procesos psicológicos del pensamiento, por tanto el mediador
ayuda al alumno a organizar, filtrar y esquematizar los estímulos de aprendizaje y
finalmente influye en la trasferencia (PRIETO, 1996).
El profesor como mediador, éste debe poner en marcha cierta parte del potencial
intelectual del alumno que no surge de forma espontánea y que es necesario trabajar
intencionalmente. El profesor es quien facilita el aprendizaje, un investigador de los
procesos acaecidos en el aula.
En el aprendizaje constructivo, el alumno logra relacionar la nueva tarea de aprendizaje con sus conocimientos y experiencias previas, almacenadas en su estructura
cognoscitiva. De ahí que esas ideas y circunstancias son comprendidas y asimiladas
significativamente durante su aprehensión. El alumno es un agente activo que procesa
y hace categorías de la información del ambiente, interpretándola, dándole sentido y
transfiriéndola a otras situaciones.
Con este nuevo escenario, por tanto, se hace necesario diseñar un sistema de aprendizaje, una nueva forma de aprender con tecnologías que esté en consonancia, por
una parte, con la nueva concepción del aprendizaje y, por otra, con las necesidades
de aprendizaje tecnológico de los sujetos con necesidades educativas especiales.
Es recomendable que los materiales informáticos permitan que el alumno haga
actividades que favorezcan la interiorización de los contenidos para poner en práctica
lo aprendido, y actividades de desarrollo cognitivo para reforzar los procesos de pensamiento implicados en el aprendizaje, a través de tareas que promuevan el desarrollo de
la capacidad intelectual.
142
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 143
Las tecnologías aplicadas a la educación especial integradora
Las actividades creadas deben potenciar los variados aspectos del desarrollo y del
aprendizaje del alumno. Cabe al profesor realizar la exploración pedagógica más oportuna
y adecuada para el alumno, para el contexto del aula y para los objetivos de aprendizaje
que pretende alcanzar:
1. Debe potenciar la atención, la memoria, el proceso de generalización, la iniciativa
para comenzar una actividad, la autonomía personal y disminuir el sentimiento de
frustración. Todo ello integrado en el diseño de los juegos y actividades para crear
situaciones y espacios variados para que el aprendizaje ocurra.
2. Debe privilegiar la interacción del alumno con el profesor, con el material, con sus
colegas a través del ordenador, que relacionen las actividades y el contenido informatizado con nuevas posibilidades de exploración también fuera del ordenador.
Es necesario considerar que los alumnos con necesidades educativas especiales
pueden aprender y que, a su vez, se van beneficiando de los desarrollos que se hagan para
los demás alumnos. En este caso el ordenador, y muy especialmente el software educativo,
puede ser aplicado considerando los aspectos de la motivación, de las dificultades y,
sobre todo, de las capacidades que presentan, y que pueden constituir una posibilidad
concreta para el desarrollo e integración social y escolar de estos alumnos.
Para el alumno con necesidades educativas especiales, el profesor que funciona como
mediador favorece su proceso de aprendizaje porque pone en marcha cierta parte de su
potencial intelectual, casi siempre ignorado. Esto no surge de forma espontánea y por eso
necesita ser trabajado de forma intencional con planteamientos que utilicen recursos y
estrategias pedagógicas dirigidas para que el aprendizaje acontezca.
LA CONTRIBUCIÓN DEL SOFTWARE “HÉRCULES Y JILÓ”: INTERROGANTES
Y RESPUESTAS SOBRE LA APLICABILIDAD Y APOYO AL APRENDIZAJE DE
ALUMNOS CON NECESIDADES EDUCATIVAS ESPECIALES
El software educativo “Hércules y Jiló” fue ideado para servir de apoyo a las intervenciones pedagógicas en el área de Ciencias Naturales, tratando conceptos relacionados
con los seres vivos que existen en la tierra (diversidad, características, clasificación,
relaciones tróficas, ambientes naturales y ambientes construidos).
Concebido de acuerdo con principios cognitivos-constructivistas, según los cuales
aprender es un proceso activo de establecimiento de puentes entre nuevas informaciones
y conocimientos anteriores, que requiere una reorganización constante de conocimientos
declarativos procedimentales y condicionantes, a partir del empleo de estrategias y metaestrategias referenciados por Pena (1984) y Tardif (1992),el software en referencia
propone servir como apoyo al trabajo pedagógico del profesor considerando las características y necesidades educativas del alumno con deficiencia intelectual.
El software “Hércules y Jiló” pretende estimular la reacción del niño mediante recursos
múltiples, buscando la interacción entre lo virtual y lo real, objetivando la alfabetización
científica, matemática, lingüística, social e informática. Está basado en cinco dimensiones: de
contenido, didáctica, cognitiva, lúdica e interactiva. Esas dimensiones son interdependientes
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
143
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 144
C. M. Alonso, A. M. Souza
y complementarias y se relacionan de manera dialéctica para que los objetivos de aprendizaje sean completamente realizados.
El funcionamiento del software educativo “Hércules y Jiló” está centrado en una serie
de actividades, de forma aleatoria y gradual, para que el usuario debidamente orientado
las puedan realizar. Esas actividades se dividen en dos categorías:
1. actividades para armar y jugar, en las que el niño utiliza el ordenador para construir
juegos para jugar fuera del ordenador.
2. actividades interactivas y virtuales en las que el niño es estimulado a participar en
una serie de juegos virtuales propuestos por el software. Todas las actividades
abordan el tema de seres vivos que existen en la tierra.
El software “Hércules y Jiló”, por sus características generales, se puede definir como
un ambiente de aprendizaje multimedia.
Un ambiente de aprendizaje multimedia consiste en la asociación de recursos (materiales, informáticos, humanos, etc.) alrededor de un proceso dinámico de enseñanzaaprendizaje. Estos recursos están estratégicamente asociados para potenciar al máximo el
acto de aprender, sea libremente con actividades lúdicas y pedagógicas, sea en situaciones
de trabajo cooperativo (SOUZA; SANTOS, 2001).
La aplicación del software educativo “Hércules y Jiló” en una clase de enseñanza
especial fijó el objetivo de observar para discutir la informática como apoyo al proceso
enseñaza-aprendizaje del alumno con deficiencia intelectual (VERDUGO, 1997, p. 24),
más específicamente su contribución como recurso de apoyo didáctico al trabajo
pedagógico del profesor.
Se buscó observar en el trabajo de la profesora que lo implementaba, utilizando el
software “Hércules y Jiló” como recurso didáctico pedagógico, con el tema del software
(los seres vivos) en los juegos y actividades, la relación de la profesora con el software y
con los alumnos en sala de aula, así como la relación de los alumnos con el ordenador
y principalmente con el software y de éstos con la profesora, trabajando con el referido
software.
Para complementar los datos recogidos a través de la observación realizada, fue
hecha, al final, una entrevista semi-estructurada con la profesora buscando conocer
sus impresiones sobre el uso del software educativo “Hércules y Jiló”, como recurso
pedagógico de apoyo a su trabajo con los alumnos.
Planteamos, ahora, la investigación realizada durante varios años sobre el diseño, la
elaboración y sobre todo la evaluación del software “Hércules y Jiló” y su repercusión en
la aplicación en el trabajo diario con alumnos con deficiencia intelectual. Presentamos la
síntesis de todo ello en forma de interrogantes con sus respectivas respuestas, que pueden
servir como orientación para el uso de software educativos como apoyo al proceso
enseñanza-aprendizaje de estos alumnos.
Interrogante 1 – ¿Qué estrategias debe presentar el software educativo para
poder provocar, adecuadamente, aprendizajes significativos y pertinentes en el
niño con deficiencia intelectual?
144
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 145
Las tecnologías aplicadas a la educación especial integradora
El estudio hecho señala la necesidad del software de responder bien al tratamiento
del contenido elegido, favoreciendo siempre la interacción con el público al que se destina.
Es necesario también que las interfaces estén diseñadas y construidas para atender a los
objetivos que se proponen, que implican considerar las características y necesidades de
los usuarios.
Interrogante 2 – ¿Qué características puede presentar un software educativo
para funcionar como apoyo al profesor en el proceso de enseñanza-aprendizaje del
alumno con deficiencia intelectual?
En relación con el profesor, la experiencia observada en la aplicación del software
destaca la importancia de que esté ambientado para que el profesor pueda conducir las
actividades con los alumnos, de forma a no dejar al alumno solo en el ordenador, sino
trabajar juntos. En este sentido, el software necesita garantizar mecanismos para que el
profesor lo maneje con facilidad para tener un papel activo de mediador del aprendizaje
con el alumno. Las actividades interactivas que conducen al trabajo colectivo favorecen
el aprendizaje. Este aspecto fue muy enfatizado en la evaluación y aplicación del software
analizado.
Observamos en la aplicación del software “Hércules y Jiló” que es muy importante
que el software sea flexible y que pueda permitir la intervención didáctica del profesor y,
a ser posible, pueda ser modificado por él, para atender a los objetivos de la enseñanza
pero sobre todo para atender a las necesidades educativas del alumno.
Las teorías de aprendizajes elegidas necesitan ser claramente contempladas en las
actividades propuestas, así como los principios pedagógicos con los cuales el profesor
va a trabajar, para fundamentar y garantizar el proceso de enseñanza-aprendizaje. En
nuestro caso, los principios del aprendizaje fueron claramente establecidos respetando las
características del aprendizaje del alumno con deficiencia intelectual para favorecer el
aprendizaje del contenido planteado. El software necesita posibilitar al profesor para que
pueda identificar los avances del alumno. Debe permitir que el profesor pueda evaluar
los progresos y dificultades del alumno para alimentar su acción pedagógica, y le permita
ascender en su conocimiento y aprendizaje.
Interrogante 3 – ¿Desde qué forma el software educativo puede servir como
factor de motivación para el niño con deficiencia intelectual en el proceso de
adquisición de conocimiento?
Resultó interesante observar en la aplicación del software “Hércules y Jiló” cuán
importante es potenciar las capacidades de los alumnos y de los profesores para promover
la motivación. Las actividades propuestas necesitan ser desafiantes y adecuadas al nivel
de interés del público y al mismo tiempo de fácil comprensión para que el usuario pueda
utilizar las funciones cognitivas en una perspectiva de aprendizaje significativo.
Particularmente en este estudio observamos que los alumnos estaban motivados para
realizar los juegos / actividades, aún sin conocer las respuestas o cuando tenían dificultades
en el manejo del ordenador o de la impresora, lo que muestra que la informática y en
especial el software educativo, adecuadamente construido y / o elegido como apoyo para
las estrategias de enseñanza en el aula, funciona como un buen colaborador del profesor
en su trabajo pedagógico.
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
145
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 146
C. M. Alonso, A. M. Souza
Otro aspecto de relevancia para que el software pueda motivar al alumno, y al mismo
tiempo apoyar el proceso en su trabajo en el aula, son las estrategias integradas al software.
En nuestro caso, el software “Hércules y Jiló”, además de permitir una diversidad de
exploración pedagógica por el profesor y por los alumnos, adoptó la estrategia de unir lo
lúdico a lo educativo, para dejar al alumno libre para las adquisiciones que se planteaba
y así favorecer aprendizajes significativos. Observamos muy claramente, en la aplicación
del software, que esta combinación de lo lúdico como soporte para la acción educativa
fue relevante para el trabajo pedagógico con los alumnos con deficiencia intelectual.
Interrogante 4 – ¿De qué manera el software educativo puede llevar al niño con
deficiencia intelectual a asumir un papel activo en la adquisición de aprendizajes?
Observamos en su aplicación que las interfaces del software “Hércules y Jiló”, las
animaciones y el manejo de fácil comprensión han permitido que el alumno con
deficiencia intelectual, el usuario al que está recomendado, jugó el papel activo en las
actividades y juegos, favoreciendo la utilización de funciones cognitivas más sencillas
en la perspectiva de aprendizaje.
Por otra parte, como plantearan los autores, el software se constituye en un ambiente
multimedia y favorece la utilización de los más variados niveles de exploración lúdica y
de aprendizaje. Los materiales constructivistas destacan la expresión y la exploración
personales dando oportunidad a los alumnos para que desarrollen su propio aprendizaje,
porque los consideran participantes activos en el proceso (VERDUGO, 1999).
Los alumnos con deficiencia intelecutal evolucionan en su desarrollo cognitivo si son
estimulados a actuar con las personas y los objetos, siendo entonces capaces de elaborar
sus propios conocimientos, como puede ser el lenguaje, el diseño, la dramatización,
expresando una creatividad muy fecunda.
Interrogante 5 – ¿Qué elementos y estrategias puede presentar el software
educativo para introducir al niño con deficiencia intelectual en una dinámica de
adquisición de nuevos conocimientos, partiendo de conocimientos ya adquiridos?
La riqueza de recursos informatizados, de los contenidos (los seres vivos) y de estrategias,
conforme se ha registrado en la fase de la investigación sobre la aplicación del software,
está potenciado en el software “Hércules y Jiló” y es utilizado como recurso de apoyo al
alumno y al profesor para atender a los diversos y diferentes niveles de interés y de
adquisición de conocimiento.
La contextualización psicopedagógica, así como las orientaciones descritas que integran el software, permiten al profesor o tutor adecuar su aplicación para introducir
nuevos conceptos y reforzarlos, siempre partiendo del nivel y de la necesidad y posibilidad del alumno. En la aplicación del software ante una clase especial para alumnos identificados con deficiencia intelectual que formó parte de esta investigación, se ha
demostrado la riqueza de estrategias y posibilidades de enriquecimiento para el proceso
de enseñanza–aprendizaje que pueden realizar estos alumnos.
Interrogante 6 – ¿Qué dinámica debe presentar el software educativo para garantizar
al profesor un papel activo y mediador en el proceso de enseñanza- aprendizaje?
146
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 147
Las tecnologías aplicadas a la educación especial integradora
La dinámica del software “Hércules y Jiló” por sí ya ofrece al profesor el papel activo
como mediador de todo el proceso de aprendizaje. Los juegos y las actividades para
realizar en el ordenador, imprimir, recortar, colorear, e instalar los juegos imponen una
acción tanto para el alumno como para el profesor.
El profesor puede utilizar el software de varias maneras, porque se trata de un material
didáctico realmente pensado y construido para permitir la exploración lúdico-pedagógica
que el profesor quiera, incluso para explorar otros contenidos.
Lo que fue observado es que el software debe ofrecer la oportunidad de ser utilizado
de varias maneras, así como favorecer el trabajo interdisciplinario.
Interrogante 7 – ¿De qué forma el software educativo puede funcionar como
facilitador de la interrelación entre alumno-alumno, alumno-profesor, y alumnoconocimiento?
La aplicación del software “Hércules y Jiló” ha demostrado que el software, con la
estructura de juegos y posibilidades infinitas para la exploración pedagógica y que
favorezca el trabajo colaborativo, puede constituir un excelente recurso pedagógico de
apoyo al proceso de enseñanza-aprendizaje del alumno con deficiencia intelectual.
Todo esto es posible porque las situaciones creadas no separan al alumno del contexto
de la sala de clase. Sitúa al niño en contacto con otros contenidos disponibles en el ambiente.
Dispone de la presencia del profesor, de sus colegas y de los demás recursos que lo
conducen a salir del aislamiento de un aprendizaje solitario para lograr un aprendizaje
colectivo.
En el caso del software ”Hércules y Jiló”, los juegos no están limitados a su propia
función ni al ambiente del ordenador: el alumno puede montarlos y jugar fuera del
ordenador, así como los profesores pueden realizar otras actividades y explorar otros
contenidos. Esto posibilita una variedad de exploración y puede dar oportunidad para que
las interacciones acontezcan, una vez que los juegos atraen a los alumnos al trabajo colectivo.
Con esa dinámica, las interacciones proyectadas por el software “Hércules y Jiló”
tratan al alumno como sujeto activo, afectivo y social que, a lo largo del proceso de
construcción de conocimientos, construye también una auto-percepción y una autoestima,
que conlleva a saberes colectivos (como los presentados por el software “Hércules y Jiló”)
y a saberes individuales (como los que él construye a partir de su propia experiencia
como ser vivo e interactivo).
CONCLUSIÓN
Después de llevar a efecto realmente lo que aquí hemos expuesto, aplicarlo y
reflexionar sobre ello, podemos afirmar que las Tecnologías de la Información y de la
Comunicación, en particular el software educativo, están considerados como elementos
de gran apoyo al trabajo del profesor y al proceso de aprendizaje del alumno.
Las TICs ofrecen una ayuda de gran importancia para la atención a las necesidades
educativas especiales, que generalmente dificultan o impiden la integración del individuo
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
147
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 148
C. M. Alonso, A. M. Souza
en la escuela y en la sociedad. Enfatizamos la construcción de materiales como software
educativos que, además de auxiliar el proceso de enseñanza-aprendizaje, puedan
contemplar las singularidades de alumnos con necesidades educacionales especiales.
Estos materiales deben contener las potencialidades metodológicas-pedagógicas
constructivas, un aspecto lúdico, posibilidades de intercomunicación, y que tecnológicamente sean amenos y amigables. Por todo esto y por el esmerado cuidado que se debe
mimar en su elaboración tanto en sonido, como en imagen y en animación, pueden
ayudar poderosamente a la integración social y escolar de los alumnos, como se ha
demostrado en la investigación realizada con el software educativo “Hércules y Jiló”.
Notas
1. El software” Hércules y Jiló” es recomendado para alumnos con deficiencia intelectual que se
encuentran en el nivel de aprendizaje que corresponde a las dos primeras series/años de estudios
del primer ciclo de la Enseñanza Fundamental.
2. La AAMR (Asociación Americana sobre Retardo Mental) define en 1992: “El retraso mental
(deficiencia intelectual) hace referencia a limitaciones sustanciales en el desenvolvimiento
corriente. Se caracteriza por un funcionamiento intelectual significativamente inferior a la
media, que tiene lugar junto a limitaciones asociadas en dos o más de las siguientes áreas de
habilidades cognitivas posibles: comunicación, cuidado personal, vida en el hogar, habilidades
sociales, utilización de la comunidad, auto – gobierno, salud y seguridad, habilidades académicas
funcionales, ocio y trabajo. El retraso mental se manifiesta antes de los dieciocho años”.
Referencias
ALMEIDA, Maria Elizabeth Bianconcini. Informática e formação de professores. Brasília: Proinfo /
MEC / SEE, 2001.
ALONSO, Catalina Maria. Aprendizaje y ordenador. Madrid: Dykinson, 2001.
COSCARELLI, Carla Viana. Leitura em ambiente multimedia e a produção de inferências. 1999.
320f. Tese (doutorado), Faculdade de Letras. UFMG, Belo Horizonte.
ESPAÑA, MEC / ES. Nuevas tecnologías y necesidades educativas especiales: orientaciones para la
atención a la diversidad. Vol. 1. Guía al profesor y otros implicados en el proceso de enseñanza
/aprendizaje, a la hora de utilizar los medios informáticos como recurso educativo con el alumno
con necesidades educativas especiales. Madrid: MEC, 1992.
GRINSPUN, Mirian Paura Sabrosa Zippin. Educação tecnológica: desafios e perspectivas. São Paulo:
Cortez, 1999.
LÉVY, Pierry. A conexão planetária. Rio de Janeiro: Editora 34, 2001.
LÓPEZ, Maria José. Nuevas tecnologías de la información y comunicación para la educación. Sevilla:
Alfar, 1995.
MARTÍ, Eduardo. Aprender con el ordenador en la escuela. Barcelona: Ediciones de la Universidad
de Barcelona; ICE –Horsori, 1992.
148
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 149
Las tecnologías aplicadas a la educación especial integradora
PAPERT, Seymour. La máquina de los niños. Barcelona: Piados, 1995.
______. Logo: computadores e educação. Trad.: José Armando Valente; Beatriz Bitelman e Afira
Vianna Ripper. São Paulo: Brasiliense, 1981.
PÉREZ, Isabel Paula. Educación especial: técnicas de intervención. Madrid: Mcgraw Hill, 2003.
PRIETO, Maria Dolores Sánchez Variables del profesor como mediador del proceso instruccional.
In: BELTRÁN, Jesús; GENOVARD, Cándido (Eds.), Psicología de la instrucción I. Variables y procesos básicos. Madrid: Síntesis. 1996. p. 194-216.
SANTOS, Gilberto Lacerda. Proposta de uma estratégia holística para a engenharia de softwares
educativos. Revista Brasileira de Tecnologia Educativa, Brasília, n. 148, p. 22-26, 2000.
SCOZ, Beltran. Psicopedagogía e realidade escolar: o problema escolar e de aprendizagem.
Petrópolis: Vozes. 1994.
SILVA, Marco. Sala de aula interativa. 2. ed. Rio de Janeiro: Quartet, 2004.
SKINNER, Burrhus Frederick. Análise do comportamento. São Paulo: EPU, 1973.
SOUZA, Amaralina Miranda. Desarrollo de un ambiente de aprendizaje de carácter cooperativo
destinado al alumno con deficiencia intelectual: el software “Hércules y Jiló”. Anales del XVII
Congreso Internacional de Informática Educativa 2005 –-Madrid: Uned – España, 2005.
______; SANTOS, Gilberto Lacerda. “Hércules y Jiló”: um software educativo de apoio á formação
docente para atuar junto a crianças com deficiência mental. Linhas Críticas. Brasília, v. 7, n. 13,
p. 275-288, jul.-dez. 2001.
TARDIF, Jacques Por un enseignement strategique: l’apport de la psichologie cognitive. Quebec:
Logiques, 1992.
TORRES, Sánchez. La palabra complementada. Madrid: Cepe, 1990.
VALENTE, José Armando. Aprendendo com o computador. Campinas: Biblioteca Central
Unicamp, 2001.
______. Liberando a mente: computadores na educação especial. São Paulo: Biblioteca Central,
1991.
VERDUGO Miguel Angel. Avances conceptuales actuales y del futuro inmediato: revisión de la
definición de 1992 de la AAMR. Revista Siglo Cero, Madrid, v. 30, n. 5, p. 27-31, 1999.
______. Un nuevo concepto de retraso mental. Salamanca: Ediciones de la Universidad de
Salamanca, 1997.
VIGOTSKI, Liev Semionovitch. A formação social da mente. Titulo original: Mind in society.
Trad.: José Cipolla Neto, Luis Silveira Menna Barreto, Solange Castro Afeche. São Paulo: Martins
Fontes, 2000.
______. Aprendizado e desenvolvimento: um processo sócio-histórico. Trad.: Marta Kohl de
Oliveira. Porto Alegre: Artmed, 1994.
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
149
linhas_criticas_24:LINHAS CRITICAS 23 March/4/11 9:23 AM Page 150
C. M. Alonso, A. M. Souza
As tecnologias aplicadas à educação especial integradora:
a contribuição do software educativo “Hércules e Jiló”
Resumo
As Tecnologias de Informação e de Comunicação aparecem como grandes aliadas do professor, favorecendo
as diferentes formas de aprender e as diferenças individuais dos alunos e dos professores. Apresentamos as
linhas fundamentais que servem de base no desenho, na elaboração e na explicação do software educativo
“Hércules e Jiló”, recomendado para o trabalho pedagógico com alunos que apresentam necessidades educativas especiais. Neste trabalho serão abordadas várias linhas de ação: 1. fundamentar sua realização com
base científica e tecnológica para lograr uma relação e motivação amigável do aluno com a
máquina; 2. oferecer uma base científico-pedagógico-metodológica para tentar alcançar atrativos os quais
o aluno possa construir conhecimento pela sua interação com o software e suas atividades derivadas.
Aspira-se que as tecnologias – em particular, o software educativo – contribuam na aprendizagem de
alunos que apresentam necessidades educativas especiais ou não.
Palavras-chave: Tecnologias da Informação e da Comunicação. Software educativo. Educação especial.
The Technologies of Information and Communication Applied to Integrating Special
Education: the contribution of the educational software “Hércules and Jiló”
Abstract
Information and Communication Technologies become great allies of the teacher in order to facilitate
the different forms of learning and favor the individual differences of students and teachers. We present
the experience of creating and applying the educational software “Hércules y Jiló” recommended for
a pedagogical relationship with pupils with special educational needs. In this process, several courses of
action have been dealt with: 1. base its realization on a scientific and technological basis so as to reach
a friendly relationship and motivation of the student with regards to the equipment; 2. offer a scientific,
pedagogical, methodological foundation to try to become an attraction such that the student can construct
knowledge through his interaction with the software and related activities. We believe that technologies
in general and the educational software in particular can contribute towards the learning process of all
students, whether they have special educational needs or not.
Keywords: Information and Communication Technologies. Educational Software. Special Education.
Les Technologies de l’Information et de la Communication Appliquées à l’Éducation
Spéciale Intégrative : la contribution du logiciel éducatif “Hércules et Jiló”
Résumé
Les technologies de l’information et de la communication deviennent de grands alliés pour le maître pour
faciliter les différentes formes d’apprendre et les différences individuelles des élèves et maîtres. Nous
présentons l’expérience de créer et appliquer le logiciel éducatif «Hércules et Jiló» recommandé en vue
d’une relation pédagogique avec les élèves porteurs de besoins spéciaux. Selon ce processus, plusieurs cours
d’action ont été pris : 1. donner à la réalisation une base scientifique et technologique de manière à ce
que l’on arrive à une relation amicale et à une bonne motivation de l’élève avec l’équipement ; 2. offrir un
fondement scientifique, pédagogique et méthodologique pour que l’élève sente un attrait pour construire son
savoir en interaction avec le logiciel et activités dérivées. Nous croyons que les technologies en général et
le logiciel éducatif en particulier peuvent contribuer à l’apprentissage de tous les élèves, qu’ils soient porteurs de besoins spéciaux ou non.
Mots clefs : Technologies de l’Information et Communication. Logiciel Éducatif. Éducation Spéciale.
Recebidas 1ª versão em: 22.02.2007
2ª versão em: 08.08.2007
Aceita 3ª versão em: 10.09.2007
150
Linhas Críticas, Brasília, v. 13, n. 24, p. 131-150, jan./jun. 2007
|
|
https://openalex.org/W2969379373
|
https://ccsenet.org/journal/index.php/jedp/article/download/0/0/40446/41644
|
English
| null |
Retrospective Reports of Parental Socialization of Physical Pain During Childhood Predicting Emerging Adults’ Current Coping With Pain
|
Journal of educational and developmental psychology
| 2,019
|
cc-by
| 7,338
|
Journal of Educational and Developmental Psychology; Vol. 9, No. 2; 2019
ISSN 1927-0526 E-ISSN 1927-0534
Published by Canadian Center of Science and Education Journal of Educational and Developmental Psychology; Vol. 9, No. 2; 2019
ISSN 1927-0526 E-ISSN 1927-0534
Published by Canadian Center of Science and Education Received: July 15, 2019 Accepted: August 14, 2019 Online Published: August 21, 2019
doi:10.5539/jedp.v9n2p74 URL: http://doi.org/10.5539/jedp.v9n2p74 Received: July 15, 2019 Accepted: August 14, 2019 Online Published: August 21, 2019
doi:10.5539/jedp.v9n2p74 URL: http://doi.org/10.5539/jedp.v9n2p74 Abstract Although a bulk of the literature has examined the methods by which people cope with physical pain, little
attention has been devoted to how people learn to respond to pain. The current study examined the relation
between college students’ reports of parental socialization of pain during childhood and their current coping with
pain. One hundred twenty-four (65.3% female) college students reported on two methods of parental socialization
they experienced during childhood: a) their mothers’ direct responses to their physical pain and b) mothers’
modeling of how they coped with their own pain. College students also reported on their own current coping
strategies regarding physical pain. Results indicated that retrospective reports of mothers’ active coping with their
own pain and mothers’ promotion responses to their child’s pain during childhood significantly positively
predicted college students’ current active coping. These findings suggest the relevance of both methods of pain
socialization (parental modeling and parents’ direct responses) for college-age children’s current coping with pain. Keywords: socialization, physical pain, emerging adults 1. Introduction A substantial body of research has been conducted regarding how people cope with pain. However, less attention
has been paid to how individuals learn specific coping skills. Much like other social processes, children learn to
cope with physical pain first in their family of origin with parents among the most influential socializers (Grusec &
Hastings, 2014). Some research has focused on parents’ influences on children’s pain management, though these
studies have focused on only one method of parental socialization (parents’ responses to children’s pain or parental
modeling). To the best of our knowledge, no study to date has simultaneously examined how different methods of
parental socialization relate to children’s coping with pain. Moreover, although the broad claim that one’s early life
experiences likely impact later functioning has received some support (Pettitt, Bates, & Dodge, 1997; Sroufe,
2005), no studies have specifically examined whether parental socialization of pain in childhood, as recalled and
reported by the offspring may be relevant for emerging adults as they cope with pain. Thus, in this study, college
students’ reports of two methods of maternal socialization during childhood are investigated—mothers’ direct
responses to children’s pain and maternal modeling through coping with their own pain, and how they relate to
college students’ reports of their current coping with pain. Retrospective Reports of Parental Socialization of Physical Pain
During Childhood Predicting Emerging Adults’ Current
Coping With Pain Julie DiNuoscio1, Vaishali V. Raval1 & Bethany L. Walker1
1 Department of Psychology, Miami University, Oxford, Ohio, USA
Correspondence: Vaishali V. Raval, Department of Psychology, Miami University, 90 N Patterson Ave, Oxford,
Ohio 45056, USA. Tel: 1-513-529-6209. E-mail: ravalvv@miamioh.edu used, and were correlated with lower levels of psychological functioning. used, and were correlated with lower levels of psychological functioning. A large body of literature has also examined children’s coping with pain, particularly among various patient
populations such as those suffering from sickle cell disease (e.g. Barakat, Schwartz, Simon, & Radcliffe, 2007),
fibromyalgia (Kashikar-Zuck et al., 2013), chronic abdominal pain (e.g. Walker, Smith, Garber, & Claar, 2007),
and pain experienced during and after operative medical procedures (Esteve, 2012). This literature has
documented that children with chronic pain use a variety of coping mechanisms, but again, passive coping seemed
to yield the worst results in terms of pain relief. Walker, Smith, Garber, and Claar (2005) tested three different
types of coping in children with chronic pain: passive, active and accommodative. Accommodative coping skills
are those that include accepting the pain and encouraging oneself. Findings indicated that passive coping was
correlated with more emotional distress whereas accommodative coping was correlated with less distress. Active
coping appeared to be more context-specific depending on the other coping mechanisms used in conjunction with
it. In another study, an important gender difference was found such that boys reported using active coping more
often than girls and active coping negatively correlated with pain intensity. In contrast, girls tended to use
internalizing or passive coping mechanisms and felt less successful about being able to cope with their pain. 1.1.1 Coping with Pain Among Emerging Adults Emerging adulthood is a developmental period between adolescence and adulthood that characterizes youth in
industrialized societies who in the pursuit of higher education have opted to postpone marriage and parenthood
(Arnett, 2000). There is limited research on the way that emerging adults manage pain, though the limited work
supports the use of a variety of coping mechanisms such as distraction (active coping), trying to rid themselves of
the pain, trying to find greater meaning about their pain (passive coping) and by using advantageous comparison
(Firmin Burger, Grigsby, Sherman, & Croft, 2011). Studies that have examined active and passive coping among
emerging adults have been consistent with the literature in showing that passive coping is less adaptive than active
coping. Specifically, Jackson, Pope, Nagasaka, Fritch, Iezzi, and Hong (2011) examined the impact of threat on the
ability to tolerate pain as well as what coping mechanisms were more effective in dealing with the pain. 1.1 Coping With Physical Pain Previous studies have demonstrated that across all age groups, people use a variety of coping skills to manage their
pain (Lachapelle & Hadjistavropoulos, 2005). Active coping skills typically involve distraction from the pain or
actively trying not to think about it, whereas passive coping mechanisms consist of ruminating about the pain and
not actively trying to alleviate it. Most research shows that active coping skills have more beneficial impacts on
one’s ability to cope with pain than passive coping skills across the lifespan. A substantial body of literature
regarding pain coping involves elderly patients with chronic pain because as people age, their bodies begin to
deteriorate at a quicker rate and as a result are more likely to experience physical pain. For example, Ersek, Turner,
and Kemp (2006) found that older patients tended to use active coping methods such as task persistence, pacing,
and coping self-statements to deal with pain, all of which were correlated with higher levels of psychological
coping. Coping methods such as relaxation are considered a passive coping method, these were less frequently 74 Journal of Educational and Developmental Psychology Vol. 9, No. 2; 2019 jedp.ccsenet.org used, and were correlated with lower levels of psychological functioning. They used
three conditions in which all participants were asked to use a Cold Pressor Test (participants have to submerge their
arm above their elbow in ice cold water): One group was told that the pain would be similar to frostbite, a second
group was reassured that it would not be very painful, and a control group was told nothing about what the pain
experience would be like. The researchers found that participants in the threat condition used more catastrophizing
(an example of passive coping method), and less active coping mechanisms such as distraction or ignoring the pain
relative to the other groups. Interestingly, participants in the threat group rated their pain sensations the same as all
other participants. Zettle, Hocker and Mick (2005) conducted a similar study using the Cold Pressor Test examining the effect of
experiential avoidance on pain management. Specifically for physical pain, experiential avoidance involves
intentionally avoiding situations that could induce pain (i.e. restricting activities). They expected that this would be
a long-term maladaptive coping mechanism, which would not be beneficial for managing pain. In support of their
hypothesis, participants who endorsed experiential avoidance had a much lower pain tolerance compared to those
who did not endorse experiential avoidance, despite the fact that both groups rated the pain sensations equally. Those who endorsed experiential avoidance also used catastrophizing as well as praying or hope to cope with the
pain. This type of coping is considered passive coping and was not beneficial in helping to reduce their pain
experience. Overall, the studies demonstrate that when college students engage in active coping when dealing with
pain, they have a higher tolerance for it, even if their pain sensitivity is just as high for those who engage in passive
coping (Jackson et al., 2011; Zettle et al., 2005). 1.2.2 Parental Modeling of Coping 1.2.2 Parental Modeling of Coping Only two published studies have examined the relation between parent's’ coping with their own pain and children’s
use of coping strategies. Gil, Williams, Thompson and Kinney (1991) examined the relationship between parental
coping and its impact on children with chronic pain. They found that for parents who used “passive adherence”
mechanisms such as focusing only on decreasing pain, their children also used this same form of coping with their
own pain. In contrast, parents who modeled “coping attempts” such as active coping, their children also used this
type of coping with their own pain. Similarly, Dasch et al. (2011) found that if parents used self-blame for coping
with their child’s illness, the child was more self-critical as well. In addition, if parents gave up on coping all
together, children blamed others for their pain. These findings demonstrate that parents’ coping strategies with
their own pain likely contribute to their children’s pain reactions and coping. 1.2.1 Parent Responses to Children’s Pain An emerging body of literature examines the relation between parents’ direct responses to children’s pain and
children’s coping skills. There are typically three types of parental responses to pain investigated: discouragement,
solicitousness, and promotion (well-behaviors) (Huguet, Miró, & Nieto, 2008). Discouragement, or minimizing
the child’s pain experience, is typically associated with higher levels of distress (e.g. Claar, Simons, & Logan,
2007). Solicitousness, or focusing the children’s attention on their pain, can also have this effect. Promotion, or
behaviors that involve actively distracting from the pain (i.e. doing a fun activity) tend to have better outcomes
regarding pain reactions. Achiam-Montal and Lipsitz (2013) found that for children with non-cardiac chest pain, if
their parents responded with solicitousness or were more protective in their response to their child’s pain (i.e. alleviating them from responsibility), the pain intensity and frequency also increased. However, for children whose
parents distracted them from the pain (which promotes wellness behaviors), they experienced pain less intensely
and less often. Consistent with these findings, it has been found that heightened attention or solicitousness,
especially by the father, towards a child’s pain is associated with higher catastrophizing (Crane & Martin, 2004;
Peterson & Palermo, 2004; Vervoort et al., 2011). Conversely, distraction and promotion of wellness behaviors are
correlated with easier child coping (Chambers et al., 2002). In a study by Chambers and colleagues (2002), parents
were instructed to either give attention to children’s pain, distract their children from pain, or were given no
instruction on dealing with their child in pain. The group in which parents attended to the child’s pain had the most
child complaints of pain followed closely by the no instruction group. These findings suggest that by turning the
child’s attention away from the pain, the parents are able to help them focus on other activities and forget their pain,
even if only temporarily. 1.2.2 Parental Modeling of Coping 1.2 Parental Socialization of Children’s Coping With Pain 1.2 Parental Socialization of Children’s Coping With Pain Children acquire norms, rules, behaviors, patterns, values, and skills necessary for competent functioning in a
given society through the process of socialization (Mccoby, 2014). Early in life, parents are considered the most
influential socialization agents, with peers, teachers, and neighbors contributing to the process as the child gets
older. Building on this foundation of socialization in the childhood, the process continues through the lifespan as
individuals enter new social environments where employers, romantic partners, and others act as socializers. Although emerging adults may learn new social behaviors, skills, and values as they age, parental socialization
during childhood is likely to continue to influence adult behaviors. Socialization is thought to occur through a variety of methods (Grusec & Hastings, 2014). Literature on parental
socialization of emotion distinguishes between what children learn through parents’ direct responses to their
behavior, emotional, or physical state (also referred to as direct socialization) and what children learn through
observational learning (Bandura, 1977)—observing how parents’ behave in particular situations themselves (also 75 Journal of Educational and Developmental Psychology Vol. 9, No. 2; 2019 jedp.ccsenet.org referred to indirect socialization) (Eisenberg, Cumberland, & Spinrad, 1998). Literature on parental socialization
of children’s engagement in physical activity also includes methods such as parental modeling as well as their
encouragement and instrumental behaviors directed to facilitate children’s physical activity (Pugliese & Tinsley,
2007). In the literature concerning socialization of pain, researchers have examined either parents’ responses to
children’s pain have been examined (Chambers, Craig, & Bennett, 2002; Crane & Martin, 2004; Dasch et al., 2011;
Vervoort, Huguet, Verhoeven, & Goubert, 2011), or parental modeling (Gil, Williams, Thompson and Kinney,
1991; and Dasch et al., 2011) but not both in the same study. In the current study, we examined both of these
methods of socialization to examine their relative predictive validity. 2.3.1 Demographic and Health Questionnaire 2.3.1 Demographic and Health Questionnaire 2.3.1 Demographic and Health Questionnaire This questionnaire was created for this study and included demographic questions such as participant age and
gender, parental education and occupation, and family income. Participants were also asked to describe any
medical conditions, medical procedures, or physical injury that they have experienced in their life. For each
medical condition, procedure, or injury reported, participants were asked the age at which it was experienced, pain
experienced (1 = no pain to 10 = the worst imaginable pain), and how they managed the pain. These questions were
analyzed to describe our sample. 2.3.2 Vanderbilt Pain Management Inventory (Brown & Nicassio, 1987)–Original Self-Report and Modified
Version for Report on Parent This measure consists of 18 self-report items that assess coping mechanisms of individuals completing the items. The measure has two subscales: active coping (7 items; e.g., “distracting attention from the pain,” “staying busy or
active”) and passive coping (11 items; e.g., “praying for relief;” “restricting social activities”). Keeping in mind
when they were experiencing pain, participants were asked to indicate (on a scale of 0 = never do when in pain to
4 = very frequently do when in pain) how often they responded in a way that would indicate either active or passive
coping. Participants completed the original self-report version to assess their current coping mechanisms
(Cronbach’s alpha for active and passive coping, respectively, = .79, and .87). This measure was modified such that
participants were asked to report on when their mother or primary caregiver was in pain during the participants’
childhood, how often they responded in a way that would indicate either active or passive coping. Cronbach’s
alpha values for active and passive coping, respectively, were .82, and .89 for the modified version to report on
parental coping. 2.3.3 Inventory of Parent/Caregiver Responses to Children’s Pain (Hugguet et al, 2008) This parent-report measure consists of 37 items assessing parents’ responses to participants’ pain. We modified the
wording from the parent report format to self-report. The measure is divided into three subscales: discouragement
(10 items; e.g., “Tell you that you may be exaggerating”), solicitousness (15 items; e.g., “Accept that in these
circumstances you do not need to do your homework”), and wellness/promotion behaviors (12 items; e.g., “Try to
distract you by suggesting attractive activities (e.g., plans for the weekend”). 2.3.1 Demographic and Health Questionnaire Participants were asked to explain
using a scale (0 = never to 4 = always) in what way their parents responded to them when they were in physical
pain while growing up. The internal consistency of the three subscales was adequate as evident by Cronbach’s
alpha values for discouragement (.95), solicitousness (.93), and wellness/promotion behaviors (.91). 2. Method A total of 124 undergraduate students (n = 103 White, n = 3 Black, n= 9 Asian, n = 7 Biracial, and n =2 American
Indian) from a mid-western university participated in this study. Participants consisted of 43 males and 81 females
with a mean age of 19.02 (SD = 1.26) years. A substantial proportion of mothers (73%) and fathers (74%) of the
participants had received a college degree or higher education. A majority of the sample (93%) had family annual
income greater than $51,000 (and for 68% of the sample, it was higher than $101,000), consistent with or above the
US median annual household income $53, 657 (U.S. Census Bureau, 2014). 2 2 Procedure 2.2 Procedure This study was approved by the IRB at the authors’ academic institution. Participants were recruited from
psychology department participant pool, and received credit towards introductory psychology course for their
participation. Participants arrived at our research lab, the study was explained, and participants provided written
informed consent. Subsequently, they completed all of the questionnaires online via Quaitrics at a time and
location convenient to them. The questionnaires included a demographic questionnaire, the Inventory of
Parent/Caregiver Responses to Children’s Pain (Huguet et al., 2008), a modified version of the Vanderbilt Pain
Management Inventory (Brown & Nicassio, 1987) in which participants responded to questions about how their
mother coped with pain, and the original version of the Vanderbilt Pain Management Inventory (Brown & Nicassio,
1987) about how participants themselves cope with pain. 2.3 Measures 2. Method
2.1 Participants 2. Method
2.1 Participants 1.3 The Current Study 1.3 The Current Study The existing literature indicates that both methods of parental socialization (parents’ responses to children’s pain
and parental modeling) are related to children’s coping. However, these methods have not been studied together in
the same study. Moreover, much of the literature on parental socialization of children’s pain focuses on the
developmental period of childhood. Although it seems reasonable to assume that parental socialization of pain
during childhood, as recalled and reported by the children, may continue to be relevant for emerging adults as they
cope with physical pain, this relationship has not been empirically investigated. In the current study, we include
both methods of parental socialization (their direct responses to child’s pain and modeling), and cross-sectionally
examine emerging adults’ retrospective reports of their mothers’ socialization of pain during childhood and reports
of their current coping with pain. Specifically, it was hypothesized that college students’ reports of their mothers’
active coping during childhood would predict their own current active coping with pain, and that college students’
reports of their mothers’ passive coping during childhood would predict their own current passive coping. It was
also hypothesized that college students’ reports of their mothers ’ solicitousness or discouragement in response to
their pain during childhood would predict the use of current passive coping mechanisms, and reports of parents’
promotion responses during childhood would predict college students’ current use of active coping. 76 Journal of Educational and Developmental Psychology Vol. 9, No. 2; 2019 jedp.ccsenet.org 3. Results Preliminary analyses included examining participants’ reports of 1) experience of pain due to a medical condition,
medical procedure, or physical injury over the course of their life and 2) current levels of pain. A substantial
proportion of the sample reported experiencing a medical condition (48%), medical procedure (54.8%), or 77 Journal of Educational and Developmental Psychology Vol. 9, No. 2; 2019 jedp.ccsenet.org physical injury (74%) over the course of their life. With respect to medical conditions, we categorized the
open-ended responses into three categories: chronic conditions (e.g., migraine headaches, scoliosis), acute
conditions (e.g., stomach flu, strep throat, Pneumonia, seasonal allergies), and asthma (See Table 1). With respect
to medical procedures, we coded the open-ended responses into three categories: dental surgery (the most common
was wisdom tooth removal), ear, nose, or throat surgery (e.g., removal of tonsils or adenoids), and other surgeries
(e.g., eye surgery, knee surgery). The average age at which participants reported experiencing the medical
condition, procedure, or injury, along with the mean reported severity of pain associated with it are provided in
Table 1. Participants’ open-ended responses regarding how they managed the pain were categorized in five
categories: a) use of medication (prescription, over the counter, inhaler), b) other treatment (e.g., wearing a cast,
splint or use crutches, physical therapy, using ice on an injured body part), c) rest (e.g., “taking lots of rest,”
“sleeping”), d) distraction (e.g., “ignore it,” “do something else”), and e) passive coping (e.g., “cried,” “let it pass,”
“did nothing”). See Table 1 for the frequency with which each of these were reported. With respect to current
experience of pain, the average rating was 3.66 (SD = .49, range 1-10) (on a scale of 1 = no pain, to 10 = the worst
imaginable pain). Of those who rated current pain as 2 or above, for 32.1% of the participants, pain was related to
injury, for 24.5% the pain was related to illness, and for 35.8% of the participants pain was related to other causes
(i.e., sprained ankle or sore muscles). 2 Pain was reported on a scale of 1 = no pain to 10 = worst imaginable pain. The range for reported pain for medical condition,
medical procedure, and physical injury was 1-10. 1 for chronic conditions, age of onset was used, for multiple surgeries or injuries data for first injury or surgery are used as more
than one were uncommon. The age range was from 2-20 years. 3. Results 3.1 The Interrelations among Maternal Coping, Mother Response to Child Pain, Participants’ reported Pain
Severity, and Participants’ current Coping 3.1 The Interrelations among Maternal Coping, Mother Response to Child Pain, Participants’
Severity, and Participants’ current Coping Bivariate correlations indicated that as hypothesized, retrospective report of maternal active coping was
significantly positively correlated with participants’ current active coping, and maternal passive coping was
significantly positively correlated with participants’ current passive coping (See Table 2). As predicted, reports of
maternal solicitousness and discouragement were positively correlated with participants’ current passive coping. Also as predicted, maternal promotion was significantly positively correlated with participants’ active coping,
however, surprisingly, it was also correlated with participants’ passive coping. Interestingly, reports of maternal
passive coping during childhood and participants’ current passive coping were positively related to participants’ Table 1. Participant reports of medical conditions, medical procedures, or physical injuries experienced
Medical condition
Medical procedure
Physical Injury
% of sample reporting
48%
54.8%
74%
Types
of
conditions,
procedures, or injuries
Chronic conditions (5%)
Acute conditions (32%)
Asthma (11%)
Dental surgery (30.6%)
ENT surgery (7.3%)
Other (16.9%)
Various body parts (arm,
hand, wrist, ankle, leg)
Participant Age1
12.28 (SD = 4.77)
14.08 (SD =4.53)
13.64 (SD = 3.55)
Reported Pain2
4.78 (SD = 3.01)
5.33 (SD = 2.95)
6.74 (SD = 2.31)
Coping with Pain
Medication
Other treatment
Rest
Distraction
Passive coping
29%
1.4%
5.6%
4.8%
7.2%
37.9%
4.4%
8.1%
2.8%
1.6%
33.9%
24.2%
7.3%
5%
4%
1 Table 1. Participant reports of medical conditions, medical procedures, or physical injuries experienced 1 for chronic conditions, age of onset was used, for multiple surgeries or injuries data for first injury or surgery are used as more
than one were uncommon. The age range was from 2-20 years. 2 Pain was reported on a scale of 1 = no pain to 10 = worst imaginable pain. The range for reported pain for medical condition,
medical procedure, and physical injury was 1-10. 78 Journal of Educational and Developmental Psychology Vol. 9, No. 2; 2019 jedp.ccsenet.org Table 2. Means, standard deviations, and correlations among key study variables
1
2
3
4
5
6
7
8
9
1. Active Coping- Mother
---
2. Passive Coping- Mother
.18
---
3. Mothers’ Solicitousness
.17
.38*
---
4. Mothers’ Discouragement
.12
.14
-.19
---
5. Mothers’ Promotion
.35*
.15
.59*
.77
---
6. Active Coping- Participant
.67*
.10
-.00
.09
.37*
---
7. 3. Results Passive Coping- Participant
.09
.60*
.36*
.34*
.28*
0.13
---
8. Participant’s pain related to medical
condition/procedure/ injury
.04
.34**
.18
.10
.11
.09
.31*
--
9. Participants’ current pain
.18
.20*
.05
.13
-.04
.13
.09
.19
--
M
(SD)
2.88
(.71)
2.21
(.64)
3.23
(.77)
1.83
(.84)
3.11
(.79)
3.01
(.62)
2.27
(.61)
5.40
(2.09)
3.66
(.49)
reported pain experienced due to medical condition, procedure, or physical injury in their life. Reports of maternal
passive coping during childhood was also significantly positively correlated with participants’ current reported
pain. reported pain experienced due to medical condition, procedure, or physical injury in their life. Reports of maternal
passive coping during childhood was also significantly positively correlated with participants’ current reported
pain. .2 Maternal Coping and Responses to Child Pain as Predictors of College Students’ Current Coping Hierarchical multiple regression analysis was used to test whether retrospective reports of maternal active coping
and promotion predicted college students’ current active coping. In the first step, mothers’ active coping was
entered and in step 2, mothers’ promotion responses were added. The results indicated that both predictors
explained 48% of the variance in college students’ active coping, with mothers’ active coping (B = .50) as a
stronger predictor of college students’ current active coping than promotion responses (B = .10) (see Table 3). Table 3. Retrospective reports of mothers’ active coping and promotion responses as predictors of college students’
current active coping
B
SE
t
R2
F
Step 1
Mothers’ active coping
.58
.06
9.34***
.44
87.16***
Step 2
Mothers’ active coping
Mothers’ promotion responses
.50
.10
.07
.04
7.45***
2.91*
.48
50.81***
*p < .05, *** p < .001. Additionally, a hierarchical multiple regression analysis was used to test whether retrospective reports of parental
passive coping, solicitousness, and discouragement predicted college students’ current passive coping. In the first
step, mothers’ passive coping was entered, in step 2, mothers’ discouragement was added, and in step 3, mothers’
solicitousness was added. The results indicated that the three predictors explained 51% of the variance, with
mothers’ passive coping as the strongest predictor (B = .41), followed by discouragement (B =.28), followed by
solicitousness (B = .18) (see Table 4). Table 3. Retrospective reports of mothers’ active coping and promotion responses as predictors of college students’
current active coping
B
SE
t
R2
F
Step 1
Mothers’ active coping
.58
.06
9.34***
.44
87.16***
Step 2
Mothers’ active coping
Mothers’ promotion responses
.50
.10
.07
.04
7.45***
2.91*
.48
50.81***
*p < .05, *** p < .001. able 3. Retrospective reports of mothers’ active coping and promotion responses as predictors of colleg
urrent active coping pective reports of mothers’ active coping and promotion responses as predictors of college students’
coping Additionally, a hierarchical multiple regression analysis was used to test whether retrospective reports of parental
passive coping, solicitousness, and discouragement predicted college students’ current passive coping. In the first
step, mothers’ passive coping was entered, in step 2, mothers’ discouragement was added, and in step 3, mothers’
solicitousness was added. 4. Discussion The aim of the current study was to examine retrospective reports of two methods of maternal socialization
(mothers’ responses to children’s pain, and maternal modeling) as predictors of emerging adults’ current coping
with physical pain in a community sample of college students. Preliminary analyses indicated that a substantial
proportion of the sample had experienced physical pain related to a medical condition, a medical procedure, or
physical injury over the course of their life. Mean levels of pain experienced due to the medical condition,
procedure or injury that participants reported were between 4.78 and 6.74 on a scale of 1 (no pain) to 10 (the worst
imaginable pain) indicating that participants in this sample experienced moderate to severe pain at some point
during their life. Using an open-ended format, participants were also asked how they managed the pain they
experienced due the medical condition, procedure, or injury they reported. Interestingly, the most common
response was the use of medication (over the counter or prescription) or other medical treatment. In this
open-ended format, participants were less likely to mention specific coping strategies (either active or passive). Using forced-choice format (i.e., their ratings on Vanderbilt Pain Management Inventory) they reported using both
active and passive coping strategies (with mean ratings of 3.01 and 2.27, respectively on a 5-point scale). Forced-choice format may allow better retrieval of the coping strategies used As predicted, regression analyses indicated that college students’ retrospective reports of their mothers’ active
coping during childhood and maternal promotion responses predicted college students’ current active coping. Moreover, college students’ retrospective reports of their mothers’ passive coping during childhood along with
maternal solicitousness and discouragement predicted college students’ current passive coping. These findings
suggests that reports of both methods of parental socialization (their direct responses to the child’s physical pain
and their modeling of their own coping with pain) are relevant and predict their college-aged children’s coping
strategies. These findings are consistent with previous research documenting the relationship between parental
coping and child coping (Gill et al., 1991), as well as between promotion responses and active coping (Chambers et
al., 2002) and discouragement and solicitousness and passive coping (Crane & Martin, 2004; Peterson & Palermo,
2004; Vervoort et al., 2011). If a child perceives their parents as dwelling on and talking about the pain, it is likely
that they will repeat those behaviors and carry them into their adult life. .2 Maternal Coping and Responses to Child Pain as Predictors of College Students’ Current Coping The results indicated that the three predictors explained 51% of the variance, with
mothers’ passive coping as the strongest predictor (B = .41), followed by discouragement (B =.28), followed by
solicitousness (B = .18) (see Table 4). Additionally, a hierarchical multiple regression analysis was used to test whether retrospective reports of parental
passive coping, solicitousness, and discouragement predicted college students’ current passive coping. In the first
step, mothers’ passive coping was entered, in step 2, mothers’ discouragement was added, and in step 3, mothers’
solicitousness was added. The results indicated that the three predictors explained 51% of the variance, with
mothers’ passive coping as the strongest predictor (B = .41), followed by discouragement (B =.28), followed by
solicitousness (B = .18) (see Table 4). 79 Journal of Educational and Developmental Psychology Vol. 9, No. 2; 2019 jedp.ccsenet.org Table 4. Retrospective reports of mothers’ passive coping, solicitousness, and discouragement as predictors of
college students’ current passive coping
B
SE
t
R2
F
Step 1
Mothers’ passive coping
.58
.08
7.78***
.37
60.56***
Step 2
Mothers’ passive coping
Mothers’ discouragement
.55
.23
.07
.06
7.77***
3.55**
.44
40.12***
Step 3
Mothers’ passive coping
Mothers’ discouragement
Mothers’ solicitousness
.41
.28
.18
.08
.06
.05
5.47***
4.55***
4.01***
.51
36.17***
*** p < .001. spective reports of mothers’ passive coping, solicitousness, and discouragement as predictors of
ts’ current passive coping 4. Discussion The same is true for active coping
mechanisms. If a child experiences their parents going about their day as normal while experiencing pain, they are
likely to exhibit the same behavior. Findings also indicated that reports of mothers’ active coping were a stronger predictor of college students’ current
active coping than promotion responses, and that reports of mothers’ passive coping were the strongest predictor,
followed by discouragement, followed by solicitousness for college students’ current passive coping. These
findings may suggest that maternal modeling of coping with pain may be more relevant than their direct responses
to their children’s pain for children’s coping strategies. However, it is important to be cautious in making such a
claim from the current data. Our data are cross-sectional and involve reports of a single respondent that are subject
to shared method variance (i.e., participants reports of their mothers’ coping with pain may be similar to their
reports of their own coping with pain simply because they are reporting on both variables). The present findings
should be explored further in future research that involves longitudinal design and multiple reports of parental 80 Journal of Educational and Developmental Psychology Vol. 9, No. 2; 2019 jedp.ccsenet.org socialization as well as of youth’s coping strategies to examine if these findings would hold. Correlational analyses indicated that reports of mothers’ passive coping during childhood and college students’
current passive coping were positively related to pain experienced due to medical condition, procedure, or physical
injury in their life. Reports of maternal passive coping during childhood was also significantly positively
correlated with participants’ current reported pain. Passive coping strategies may be ineffective in effectively
managing pain and it is possible that individuals who observe others as using passive coping themselves learn to
use passive coping, which may be ineffective in managing their pain and they may experience higher severity of
pain. Our data are cross-sectional and involve reports of a single respondent, and thus, it is not possible to make
any causal claims. However, our data suggest associations among reports of maternal passive coping, individuals’
own passive coping, and individual’s experienced pain that should be explored in future research with longitudinal
design and multiple respondents. Correlational analyses indicated that reports of mothers’ passive coping during childhood and college students’
current passive coping were positively related to pain experienced due to medical condition, procedure, or physical
injury in their life. 4.1 Limitations and Future Directions We relied on college students’ retrospective reports of parental socialization during childhood, which are subject to
two sets of biases: First, children may subjectively experience the same objective parent behavior in different ways,
and thus, we assessed college students’ subjective representation of parent behavior rather than actual parent
behavior. Second, there may be bias in recall of parent behavior such that participants’ current relationship with the
parent as well as their current coping with pain may interfere with them accurately recalling how their mothers’
responded to their pain and how they coped with their own pain. A second limitation of the study was that our sample was primarily Caucasian, middle and upper middle-class
college students. This group does not represent emerging adult population across United States, in particular, those
who are racially and ethnically diverse, those who are from lower social class, or those who do not attend college. Future research with diverse populations from the United States is needed. A third limitation was that we examined
the relation between reports maternal socialization and college students’ current coping with pain cross-sectionally,
and that a single respondent (college students) reported on all study variables. Future studies may utilize parents’
reports of their own coping and response styles, and prospectively examine the relation between parental
socialization and children’s coping with pain. Further, future research may examine how college students’ active
and passive coping strategies are related to their daily functioning, specifically their participation in academic,
work, and social activities and responsibilities. Finally, future research also examine parental socialization of
children’s physical pain along with socialization of other emotional and behavioral states. Scholars have argued
that socialization is a domain-specific process (Grusec & Davidov, 2010), and it would be beneficial to examine
similarities and differences in parental socialization approaches to children’s physical pain as compared to
emotional distress. Despite limitations, the present study was the first to simultaneously examine reports of different methods of
parental socialization of pain, and to assess which methods may be more relevant for college-aged adults’ current
coping. This line of research has important implications for developing intervention or education programs for
both parents and youth in using more effective coping strategies for everyday experiences of pain, as well as for
pain related to specific medical conditions, procedures, or physical injuries. 4. Discussion Reports of maternal passive coping during childhood was also significantly positively
correlated with participants’ current reported pain. Passive coping strategies may be ineffective in effectively
managing pain and it is possible that individuals who observe others as using passive coping themselves learn to
use passive coping, which may be ineffective in managing their pain and they may experience higher severity of
pain. Our data are cross-sectional and involve reports of a single respondent, and thus, it is not possible to make
any causal claims. However, our data suggest associations among reports of maternal passive coping, individuals’
own passive coping, and individual’s experienced pain that should be explored in future research with longitudinal
design and multiple respondents. References Achiam-Montal, M., & Lipsitz, J. D. (2014). Does parental response to children's pain moderate the association
between pain severity and functional disability? An examination of noncardiac chest pain. Journal of
Pediatric Psychology, 39, 35-44. https://doi.org/10.1093/jpepsy/jst068 Achiam-Montal, M., & Lipsitz, J. D. (2014). Does parental response to children's pain moderate the association
between pain severity and functional disability? An examination of noncardiac chest pain. Journal of
Pediatric Psychology, 39, 35-44. https://doi.org/10.1093/jpepsy/jst068 Achiam-Montal, M., & Lipsitz, J. D. (2014). Does parental response to children's pain moderate the association
between pain severity and functional disability? An examination of noncardiac chest pain. Journal of
Pediatric Psychology, 39, 35-44. https://doi.org/10.1093/jpepsy/jst068 Arnett, J. J. (2014). Socialization in emerging adulthood: from the family to the wider world, from socialization to
self-socialization. In J. E. Grusec and P. D. Hastings (Eds), Handbook of socialization: Theory and research
(2nd ed., pp. 85-108). New York: Guilford Press. Arnett, J. J. (2014). Socialization in emerging adulthood: from the family to the wider world, from socialization to
self-socialization. In J. E. Grusec and P. D. Hastings (Eds), Handbook of socialization: Theory and research
(2nd ed., pp. 85-108). New York: Guilford Press. Arnett, J. J. (2014). Socialization in emerging adulthood: from the family to the wider world, from socialization to
self-socialization. In J. E. Grusec and P. D. Hastings (Eds), Handbook of socialization: Theory and research
(2nd ed., pp. 85-108). New York: Guilford Press. Bandura, A. (1977). Social learning theory. Englewood Cliffs, N.J.: Prentice Hall. Bandura, A. (1977). Social learning theory. Englewood Cliffs, N.J.: Prentice Hall. Buenaver, L. F., Edwards, R. R., Smith, M. T., Gramling, S. E., & Haythornthwaite, J. A. (2008). Catastrophizing
and pain-coping in young adults: Associations with depressive symptoms and headache pain. Journal of Pain,
9, 9311-319. https://doi.org/10.1016/j.jpain.2007.11.005 Buenaver, L. F., Edwards, R. R., Smith, M. T., Gramling, S. E., & Haythornthwaite, J. A. (2008). Catastrophizing
and pain-coping in young adults: Associations with depressive symptoms and headache pain. Journal of Pain,
9, 9311-319. https://doi.org/10.1016/j.jpain.2007.11.005 Chambers, C. T., Craig, K. D., & Bennett, S. M. (2002). The impact of maternal behavior on children's pain
experiences:
An
experimental
analysis. Journal
of
Pediatric
Psychology,
27,
293-301. https://doi.org/10.1093/jpepsy/27.3.293 Chambers, C. T., Craig, K. D., & Bennett, S. M. (2002). The impact of maternal behavior on children's pain
experiences:
An
experimental
analysis. Journal
of
Pediatric
Psychology,
27,
293-301. https://doi.org/10.1093/jpepsy/27.3.293 Claar, R. L., Simons, L. E., & Logan, D. E. (2008). References Parental response to children's pain: The moderating impact of Claar, R. L., Simons, L. E., & Logan, D. E. (2008). Parental response to children's pain: The moderating impact of Claar, R. L., Simons, L. E., & Logan, D. E. (2008). Parental response to children's pain: The modera 81 Journal of Educational and Developmental Psychology Vol. 9, No. 2; 2019 jedp.ccsenet.org children's
emotional
distress
on
symptoms
and
disability. Pain,
13,
172-179. https://doi.org/10.1016/j.pain.2007.12.005 Crane, C., & Martin, M. (2004). Social learning, affective state and passive coping in irritable bowel syndrome and
inflammatory
bowel
disease. General
Hospital
Psychiatry,
2,
50-58. https://doi.org/10.1016/j.genhosppsych.2003.07.005 Dasch, K., Russell, H., Kelly, E., Gorzkowski, J., Mulcahey, M., Betz, R., & Vogel, L. (2011). Coping in caregivers
of youth with spinal cord injury. Journal of Clinical Psychology In Medical Settings, 18, 361-371. https://doi.org/10.1007/s10880-011-9258-z DeNavas-Walt, Carmen and Bernadette D. Proctor, U.S. Census Bureau. (2014). Income and Poverty in the United
States:
2014. U.S. Government
Printing
Office,
Washington,
DC,
2015. Retrieved
from
https://www.census.gov/content/dam/Census/library/publications/2015/demo/p60-252.pdf Eisenberg, N., Cumberland, A., & Spinrad, T. L. (1998). Parental socialization of emotion. Psychological Inquiry,
9(4), 241-273. https://doi.org/10.1207/s15327965pli0904_1 Esteve, R. V. (2012). Children's pain perspectives. Child: Care, Health & Development, 38, 441-452. https://doi.org/10.1111/j.1365-2214.2011.01297.x Firmin, M. W., Burger, A. J., Grigsby, M. E., Sherman, A. L., & Croft, J. N. (2011). Coping constructs related to
college students with chronic pain. Journal of Ethnographic & Qualitative Research, 6, 32-44. Grusec, J. E., & Davidov, M. (2010). Integrating different perspectives on socializationtheory and research: A
domain-specific
approach. Child
Development,
81,
687-709. https://doi.org/10.1111/j.1467-8624.2010.01426.x Grusec J. E., & Hastings, P. D. (2014). Preface. In J. E. Grusec and P. D. Hastings (Eds), Handbook of socialization:
Theory and research (2nd ed.). New York: Guilford Press. Huguet, A., Miró, J., & Nieto, R. (2008). The inventory of parent/caregiver responses to the children's pain
experience
(IRPEDNA):
Development
and
preliminary
validation. Pain,
13,
128-139. https://doi.org/10.1016/j.pain.2007.04.004 Jackson, T., Pope, L., Nagasaka, T., Fritch, A., Iezzi, T., & Hong, C. (2005). The impact of threatening information
about pain on coping and pain tolerance. British Journal of Health Psychology, 10, 441-451. https://doi.org/10.1348/135910705X27587 Kapoor, S., Thorn, B., & Eyer, J. (2013). College students with chronic or recurrent pain: a qualitative exploration
of their experiences. Journal of Pain, 14, 1. https://doi.org/10.1016/j.jpain.2013.01.753 Kashikar-Zuck, S., Sil, S., Lynch-Jordan, A. M., Ting, T. V., Peugh, J., Schikler, K. N., … & Lovell, D. J. (2013). References Changes in pain coping, catastrophizing, and coping efficacy after cognitive-behavioral therapy in children
and
adolescents
with
juvenile
fibromyalgia. The
Journal
of
Pain,
14(5),
492-501. https://doi.org/10.1016/j.jpain.2012.12.019 Lachapelle, D. L., & Hadjistavropoulos, T. (2005). Age-related differences among adults coping with pain:
Evaluation of a developmental life-context model. Canadian Journal of Behavioural Science, 37, 123-137. https://doi.org/10.1037/h0087250 Lynch, A. M., Kashikar-Zuck, S., Goldschneider, K. R., & Jones, B. A. (2007). Sex and age differences in coping
styles among children with chronic pain. Journal of Pain and Symptom Management, 33, 208-216. https://doi.org/10.1016/j.jpainsymman.2006.07.014 Mccobby, E. E. (2014). Historical overview of socialization research and theory. In J. E. Grusec and P. D. Hastings
(Eds), Handbook of socialization: Theory and research (2nd ed., pp. 3-31). New York: Guilford Press. Peterson, C. C., & Palermo, T. M. (2004). Parental reinforcement of recurrent pain: The moderating impact of
child depression and anxiety on functional disability. Journal of Pediatric Psychology, 29, 331-341. https://doi.org/10.1093/jpepsy/jsh037 Pettitt, G. S., Bates, J. E. & Dodge, K. A. (1997). Supportive parenting, Ecological Context, and Children's
Adjustment:
A
seven-Year
Longitudinal
Study. Child
Development,
68(5),
908-923. https://doi.org/10.2307/1132041 Pugliese, J. & Tinsley, B. (2007). Parental Socialization of Child and Adolescent Physical Activity: A
Meta-Analysis. Journal of Family Psychology, 21, 331-343. https://doi.org/10.1037/0893-3200.21.3.331 82 Journal of Educational and Developmental Psychology Vol. 9, No. 2; 2019 Vol. 9, No. 2; 2019 jedp.ccsenet.org Simons, L., Claar, R., & Logan, D. (2008). Chronic pain in adolescence: Parental responses, adolescent coping,
and their impact on adolescents pain behaviors. Journal of Pediatric Psychology, 33, 894-904. https://doi.org/10.1093/jpepsy/jsn029 Sroufe, L. A. (2005). Attachment and development: A prospective, longitudinal study from birth to adulthood. Attachment and Human Development, 7 (4), 349-367. https://doi.org/10.1080/14616730500365928 Vervoort, T., Goubert, L., & Crombez, G. (2010). Parental responses to pain in high catastrophizing children: The
moderating
effect
of
child
attachment. Journal
of
Pain,
11,
755-763. https://doi.org/10.1016/j.jpain.2009.11.012 Vervoort, T., Huguet, A., Verhoeven, K., & Goubert, L. (2011). Mothers' and fathers' responses to their child's pain
moderate the relationship between the child's pain catastrophizing and disability. Pain, 152, 786-793. https://doi.org/10.1016/j.pain.2010.12.010 Walker, L. S., Smith, C. A., Garber, J., & Claar, R. L. (2005). Testing a model of pain appraisal and coping in
children
with
chronic
abdominal
pain. Health
Psychology,
24,
364-374. https://doi.org/10.1037/0278-6133.24.4.364 Walker, L. S., Smith, C. A., Garber, J., & Claar, R. L. (2007). Appraisal and coping with daily stressors by pediatric
patients
with
chronic
abdominal
pain. Journal
of
Pediatric
Psychology,
32(2),
206-216. https://doi.org/10.1093/jpepsy/jsj124 White, C. References P., Mendoza, J., White, M. B., & Bond, C. (2009). Chronically ill mothers experiencing pain: Relational
coping
strategies
used
while
parenting
young
children. Chronic
Illness,
5,
33-45. https://doi.org/10.1177/1742395309102820 Zettle, R. D., Hocker, T. R., & Mick, K. A. (2005). Differential strategies in coping with pain as a function of level
of experiential avoidance. Psychological Record, 55, 511-524. https://doi.org/10.1007/BF03395524 Copyrights Copyright for this article is retained by the author(s), with first publication rights granted to the journal Copyright for this article is retained by the author(s), with first publication rights granted to the journal. This is an open-access article distributed under the terms and conditions of the Creative Commons Attribution
license (http://creativecommons.org/licenses/by/4.0/). This is an open-access article distributed under the terms and conditions of the Creative Commons Attribution
license (http://creativecommons.org/licenses/by/4.0/). 83 83
|
https://openalex.org/W2109385606
|
https://www.scielo.br/j/sa/a/Rp8njMgTm7sy4McNLwkQmQN/?lang=en&format=pdf
|
Portuguese
| null |
Lime and gypsum application on the wheat crop
|
Scientia Agrícola
| 2,002
|
cc-by
| 7,551
|
APLICAÇÃO DE CALCÁRIO E GESSO NA CULTURA DO TRIGO RESUMO: A calagem e a aplicação de gesso levam a modificações químicas no perfil do solo que podem
influenciar o crescimento radicular e a produção de culturas anuais. Um experimento foi realizado em Latossolo
Vermelho distrófico textura argilosa, em Ponta Grossa (PR), com o objetivo de avaliar os efeitos da calagem
(sem calcário e 4,5 t ha
-1 de calcário dolomítico aplicado na superfície, em dose total e 1/3 da dose por ano
durante 3 anos, e incorporado) e de doses de gesso na superfície (0, 3, 6 e 9 t ha
-1) sobre o crescimento
radicular, a nutrição mineral e a produção de grãos de trigo (cv. OR 1). O delineamento experimental empregado
foi em blocos ao acaso com parcelas subdivididas, com três repetições. Os tratamentos com calcário (parcelas)
foram aplicados em julho, e as doses de gesso (subparcelas) em outubro de 1998. A cultura do trigo foi
avaliada no inverno de 2000. Em condições de ausência de déficit hídrico, não houve limitação no crescimento
radicular do trigo, em profundidade, para teor de Ca trocável de 6 mmolc dm
-3. A incorporação de calcário
aumentou a concentração de Mg nas folhas, mas a produção de grãos de trigo não foi influenciada pela
correção da acidez do solo através da calagem na superfície, com ou sem parcelamento, ou com incorporação. A aplicação de gesso aumentou a concentração foliar de Ca e S, causando acréscimos na produção de
grãos. O nível crítico de S-SO4
2- no solo, na camada de 0-20 cm, extraído pelo acetato de amônio 0,5 mol L
-1 em
ácido acético 0,25 mol L
-1, foi de 25,8 mg dm
-3. g
Palavras-chave: Triticum aestivum L., crescimento radicular, cálcio, enxofre, sistema plantio direto duardo Fávero Caires1,4*; Itacir Cesar Feldhaus2,3; Gabriel Barth2; Fernando José Garbuio 1Depto. de Ciência do Solo e Engenharia Agrícola - UEPG - Campus de Uvaranas, Av. General Carlos Cavalcanti nº
4748 - CEP: 84030-900 - Ponta Grossa, PR. 2Graduando em Agronomia - UEPG. 3PIBIC/CNPq Fellow. 4CNPq Fellow. *Corresponding author <efcaires@uepg.br> 4CNPq Fellow. *Corresponding author <efcaires@uepg.br> ABSTRACT: Root growth and crop yield can be affected by chemical modifications of the soil profile owing to
lime and gypsum applications. A field trial was carried out on a dystrophic Clayey Rhodic Hapludox at Ponta
Grossa, PR, Brazil, aiming to evaluate lime (without or with incorporation into the soil) and gypsum effects on
root growth, mineral nutrition and grain yield of wheat (cv. OR 1). A randomized complete block design was
used, with three replications, in a split-plot experiment. Treatments with dolomitic limestone (without lime and
4.5 t ha
-1 of lime applied on the surface, in total rate and 1/3 of the requirement per year during 3 years, or
incorporated into the soil) were applied in July 1998 (main plots) and the rates of gypsum (0, 3, 6 and 9 t ha
-1) in
October 1998 (subplots). Wheat was evaluated in the 2000 winter season. In conditions of water deficit absence,
there was no limitation in root growth in depth, for exchangeable Ca of 6 mmolc dm
-3. Lime incorporation of
lime increased the Mg concentration in the leaves, but wheat yield was not influenced by the correction of soil
acidity through liming treatments. Gypsum increased the concentrations of Ca and S in wheat leaves, with
significant effects on grain yield. The critical level of S-SO4
2- in the 0-20 cm soil layer, extracted by ammonium
acetate 0.5 mol L
-1 in acetic acid 0.25 mol L
-1, was 25.8 mg dm
-3. Key words: Triticum aestivum L., root growth, calcium, sulphur, no-tillage system 357 357 MATERIAL AND METHODS The experiment was carried out in Ponta Grossa,
PR, Brazil, Regina Farm, on a dystrophic Clay Rhodic
Hapludox, used before as pastureland. At the beginning
of the experiment, soil chemical (Pavan et al., 1992) and
granulometric (EMBRAPA, 1997) analyses of the 0-20 cm
layer showed the following results: pH (1:2.5 soil:0.01
mol L
-1 CaCl2 suspension) 4.6; 78 mmolc dm
-3 of H
++Al
3+;
3 mmolc dm
-3 of Al
3+; 25 mmolc dm
-3 of Ca
2+; 20 mmolc
dm
-3 of Mg
2+; 3.6 mmolc dm
-3 of K
+; 0.3 mg dm
-3 of P
(Mehlich-1); 31 g dm
-3 of organic carbon, and 38% of
base saturation, and clay, silt and sand contents of 580,
130 and 290 g kg
-1,
respectively. The subsoil (40-60 cm)
had 6 mmolc dm
-3 of Ca
2+, 8 mmolc dm
-3 of Al
3+ and 620
g kg
-1 of clay. At the beginning of flowering, leaves were
collected from 30 plants of each subplot, when the first
to fourth leaf from the apices of the plants were collected. These samples were washed in de-ionized water, dried
in a forced-air oven at 60°C until constant weight was
achieved, and ground. The concentrations of N, P, K, Ca,
Mg, and S were analyzed through the methods described
by Malavolta et al. (1997). At that same time, root
samples were also collected by means of a sampling tube
at four depths (0-10, 10-20, 20-40, and 40-60 cm), when
6 sub-samples were taken, 3 from the sowing row and 3
between rows, to form a composite sample. The samples,
with a diameter of 3.5 cm, were randomly selected in only
five treatments of lime (L) and gypsum (G): control (L0L0),
gypsum (L0G9), lime on the surface (L4,5supG0), lime on the
surface + gypsum (L4,5supG9) and incorporated lime
(L4,5incG0). The roots were separated from the soil by
dispersion in water through a 0.5 mm mesh sieve. Root
length was estimated by the method of Tennant (1975)
and the mean radius and root surface area according to
Hallmark & Barber (1984). A randomized complete block design was used,
with three replications in the experiment with a split-plot
arrangement. Caires et al. Caires et al. immediately before harrowing with a disk harrow. In the
treatment with annual splitting of surface-applied lime, the
second application was conducted in May 1999, and the
third, in May 2000. The areas of each plot and subplot
were 224 m
2 and 56 m
2, respectively. The sequence of
crops used was soybean (1998/1999), barley (1999),
soybean (1999/2000) and wheat (2000). The present
work addresses only the wheat crop, since the root
growth and nutrition of this particular crop were studied
more thoroughly. When gypsum, which is relatively soluble (Bolan
et al., 1991 cited by Sumner, 1995), is applied to a topsoil
with acid subsoil, leaching occurs under the influence of
an excess of moisture. Consequently, there is an increase
in calcium supply and a decline in aluminum toxicity in
the subsoil (Sumner, 1995). The positive effects of
gypsum observed in the most diverse soil and weather
conditions (Pavan et al., 1984; Sumner et al., 1986;
Farina & Channon, 1988; Raij et al., 1998) indicate that
its utilization can also be a good alternative for the
amelioration of the subsoil root environment in no-tillage
management systems. Doubts remain, however, as to the
conditions in which favorable effects of the gypsum on
crop yield can be expected, probably as a result of the
complex changes in the soil chemical attributes that
derive from its application. Wheat, cv. OR 1, was sown on June 10th, 2000,
at a seeding rate of 35 seeds m
-1, and row spacing of 0.17
m. Fertilizers were applied at rates of 330 kg ha
-1 of 10-
20-20 (N – P2O5 – K2O) in the sowing, and 100 kg ha
-1
of N as urea in top dressing. Soil samples were taken prior to wheat sowing,
corresponding to 23 months after liming and 20 months
after gypsum application. Rainfall in the period between
lime and gypsum application and soil sampling was 2915
and 2285 mm, respectively. Twelve soil core samples per
subplot were taken by means of a soil probe sampler to
form a composite sample of the 0-5 , 5-10 and 10-20 cm
layers, and five cores of the 20-40, 40-60 and 60-80 cm
layers. The pH and H
+ + Al
3+ (total acidity pH 7.0), Al
3+,
Ca
2+, Mg
2+ and K
+ concentrations were determined
according to Pavan et al. (1992). Caires et al. Analyses of S-SO4
2- for
the different soil depths were also performed through
extraction by ammonium acetate 0.5 mol L
-1 in acetic acid
0.25 mol L
-1 and later determination by the turbidimetric
method described by Vitti & Suzuki (1978). The present work was carried out with the aim
of evaluating root growth, mineral nutrition and wheat
grain yield in relation to changes in soil chemical traits
brought about by surface liming at full or split rates, and
incorporated lime, and by the application of gypsum rates,
in no-tillage systems. INTRODUCTION In recent years, there has been increasing
interest in finding alternative ways to establish crops
under no-tillage in new areas, without soil disturbance. The benefits of this practice are related to the
maintenance of the chemical and structural traits of the
soil, increased erosion control, and economy in the
operations of lime incorporation and tillage. However, if
soil acidity is not adequately corrected, root growth and
plant nutrition may be compromised. Under no-tillage management, considerable
increases in organic carbon and nitrogen concentrations
occur, mainly in the surface layers of the soil, as a result
of plant residue deposition and absence of disturbance
(Anghinoni & Salet, 1998). Recent reports have shown
high crop yields, in the absence of liming, in acidic soils
under this system (Caires et al., 1998; 1999; Pöttker &
Ben, 1998). The explanations for this have been
associated to decreased aluminum toxicity (Salet et al.,
1996), sufficient availability of exchangeable calcium and
magnesium (Caires et al., 1998), and adequate nutrient
uptake by the crops, probably as a result of higher soil
water availability in the soil (Caires & Fonseca, 2000). Agricultural yield limitation caused by subsoil
acidity, resulting from restraints to root growth and water
and nutrient uptake by the crops have been widely
reported in the literature (Pavan et al., 1982; Ritchey et
al., 1982; Sumner et al., 1986; Farina & Channon,
1988). Scientia Agricola, v.59, n.2, p.357-364, abr/jun. 2002 358 MATERIAL AND METHODS In the main plots, four treatments with
dolomitic limestone with 89% ECCE were applied: control
(no lime); split application of lime on the surface (three
yearly applications of 1.5 t ha
-1); lime on the surface (4.5
t ha
-1) and incorporated lime (4.5 t ha
-1). The lime rate
utilized was estimated by the soil base saturation method
at 70%, in the 0-20 cm layer. In the subplots, four different
rates of gypsum (byproduct of the phosphoric acid
industry) were surface-applied: 0, 3, 6 and 9 t ha
-1. Dolomitic limestone and gypsum were applied in July and
October 1998, respectively. The incorporated lime
treatment consisted of two separate operations. In one,
half of the lime was surface broadcasted by hand and
the soil plowed to the 20 cm depth with a disk plow. In
the other part, the remaining half of the lime was added
by hand on the surface, followed by plowing and Throughout the development period of the wheat
crop, there was no water limitation. Rainfall was 181, 98,
95, 250 and 283 mm, respectively, in the months of June,
July, August, September, and October 2000. However,
there occurred severe persistent frosts at the start of the
crop development, which resulted in intense tillering. Scientia Agricola, v.59, n.2, p.357-364, abr./jun. 2002 Lime and gypsum for wheat crop 359 displacement reaction, with the SO4
2- displacing the OH
-
of the surface of soil particles, involving hydrated oxides
of Fe and Al (Reeve & Sumner, 1972). There was a linear
increase in exchangeable Ca concentrations as a function
of the gypsum rates at the six depths studied. In addition
to the downward movement of Ca, the gypsum also
promoted leaching of exchangeable Mg (0-20 cm) and
K (0-40 cm), causing an elevation of the levels of these
nutrients in the subsoil (40-60 and 60-80 cm). After maturation, the wheat was harvested and
threshed, when time grain yield was determined at 130
g kg
-1 humidity. The middle twenty rows for four meters
in length were harvested from each subplot, while two
meters of each border were discarded. The results were submitted to variance and
regression analyses. RESULTS AND DISCUSSION The results of chemical analyses of soil samples
collected 23 months after liming (Table 1) showed that
surface-applied lime, at full or split rates, and incorporated,
led to an increase of pH in CaCl2 0.01 mol L
-1, Ca and Mg
concentrations and base saturation, and a decrease of H
+
+ Al
3+ levels in the 0-5 cm layer. Soil base saturation
obtained for the surface layer (0-5 cm), both with surface-
applied and incorporated lime, was close to the estimated
(70%) for the sample collected to the depth of 0-20 cm. These results are in line with those observed in other
reports (Caires et al., 2000; Weirich Neto et al., 2000). In
the 5-10 and 10-20 cm layers, a greater response of lime
was achieved with its incorporation into the soil, although
surface liming, at full or split rates, also presented, to a
lower degree, beneficial effects in acidity correction. The leaching of exchangeable K which took place
with the application of gypsum rates was not influenced
by liming and was not very intense either, despite the high
levels of K
+ in the soil (Table 2). The mean decreases in
the concentrations of exchangeable K, for each ton of
gypsum applied, were 0.08, 0.05, 0.07 and 0.06 mmolc
dm
-3, respectively, at the depths of 0-5, 5-10, 10-20 and
20-40 cm. The increase in exchangeable K in the subsoil
layers (40-60 and 60-80 cm) was around 0.06 mmolc dm
-3
per ton of gypsum. Even though exchangeable K leaching
as a result of the use of gypsum may occur depending
on the soil type (Sousa & Ritchey, 1986; Sumner, 1995),
K
+ losses by leaching under a no-tillage system, as a
consequence of gypsum application, have been of small
magnitude (Caires et al., 1998). g
y
Liming, regardless of the application method, did
not affect acidity of subsoil layers (20-40, 40-60 and 60-
80 cm), even though lime, especially when incorporated,
promoted downward movement of Ca and Mg to the
deeper layers of the soil, causing an elevation in the base
saturation in depth (Table 1). Despite the fact that such
effects are beneficial to plant development, the movement
of Ca and Mg is not a good parameter to assess the
downward movement of lime in the soil. MATERIAL AND METHODS In the absence of a significant
interaction lime vs gypsum on the variables studied, the
effects of liming were compared by the Tukey test at 5%
probability, and the effects of gypsum, through regression
analyses by orthogonal polynomials, by the means of the
observations. The criterion adopted for choosing the
model was the magnitude of the significant coefficients
of determination at 5% probability. Since the leaching of exchangeable Mg has been
a frequent response in the studies involving gypsum
application (Carvalho et al., 1986; Syed-Omar & Sumner,
1991; Oliveira & Pavan, 1996), its utilization has not been
recommended alone, but in association to liming. However,
in the 0-5 and 5-10 cm layers, there was a significant
interaction between liming treatments and gypsum rates. According to the adjusted regression equations, the decline
in exchangeable Mg levels at 0-5 cm, for each ton of
gypsum applied, were 1.0, 1.7, 2.0 and 2.2 mmolc dm
-3,
respectively, for the treatments without lime, split-rate lime
on the surface, full-rate lime on the surface and
incorporated lime. In the 5-10 cm layer, the decline of
exchangeable Mg caused by gypsum only occurred with
liming. This decrease was around 1.5 mmolc dm
-3 (surface-
applied lime at split rates), 1.6 mmolc dm
-3 (surface-applied
lime at full rate) and 1.7 mmolc dm
-3 (incorporated lime) of
Mg
2+, per ton of gypsum. The downward movement of Mg
2+
is more significant with greater concentrations of the
nutrient in the soil, in agreement with those results
obtained by Caires et al. (1998). Lime and gypsum for wheat crop RESULTS AND DISCUSSION This shows
that the correction of soil acidity with the incorporation
of lime favors the formation of thinner roots in this soil
layer. Nevertheless, root density and surface area of
wheat were not significantly influenced by liming and/or
gypsum treatments. The gypsum S-SO4
2- was distributed uniformly
throughout the soil profile instead of accumulating in one
layer, which is in agreement with the results obtained by
Sousa & Ritchey (1986). The rate at which sulfate moves
downward is variable for different soils (Quaggio et al., The wheat crop showed 67% of root length in the
0-20 cm layer, regardless of liming, surface applied or
incorporated, and gypsum application. Approximately 33% Scientia Agricola, v.59, n.2, p.357-364, abr./jun. 2002
Table 1 - Changes in soil chemical traits for different depths, 23 months after the application of liming treatments. (1) 1/3 of the lime rate appplied per year on the surface for 3 years. (2) full-rate lime on the surface in a single application. RESULTS AND DISCUSSION Farina (1993)
cited by Sumner (1995) also observed appreciable
movement of Ca and Mg with the application of lime
without a significant decrease in total acidity pH 7.0 of
the subsoil. This downward movement of Ca and Mg from
the lime to deeper layers may be related to the formation
of hydrosoluble organic compounds present in the plant
residue (Ziglio et al., 1999; Franchini et al., 1999) or
derive from the use of nitrogen fertilizers (Pearson et al.,
1962; Weir, 1975) associated to nitrification-dependent
reactions. The increase in soil base saturation obtained with
the application of gypsum rates (0-5, 20-40, 40-60 and
60-80 cm) derived from the increase in exchangeable
calcium, having no relation to acidity correction (Table 2). This effect is clearly observed through the absence of the
gypsum effect on the soil total acidity pH 7.0. The application of gypsum, after 20 months, did
not influence soil acidity (Table 2), but caused a raise in
pH in the subsurface layers (40-60 and 60-80 cm). The
increase in subsoil pH through the application of gypsum
was also found in other reports (Sousa & Ritchey, 1986;
Caires et al., 1999). Such effect has been attributed to a The levels of S-SO4
2- at the various depths were
not significantly influenced by lime applied on the surface,
with or without splitting, or incorporated. The mean
concentrations of S-SO4
2-,
in mg dm
-3, were 16.6 (0-5 cm),
13.0 (5-10 and 10-20 cm), 14.0 (20-40 cm), 9.0 (40-60
cm) and 5.2 (60-80 cm). Scientia Agricola, v.59, n.2, p.357-364, abr/jun. 2002 Caires et al. 360 1993; Caires et al., 1998) and must be slower in soils
richer in clay. The application of gypsum rates raised S-SO4
2-
concentrations in the six depths (Figure 1). The
mean increase in those concentrations per ton of
gypsum were 9.7, 10.6, 14.2, 16.8, 19.0 and 8.9
mg dm
-3, respectively, at the depths of 0-5, 5-10, 10-
20, 20-40, 40-60 and 60-80 cm. Therefore, there
was a consistent increase in sulfate levels in the soil
as a function of gypsum rates; the greatest
accumulation occurred for the 40-60 cm depth after 20
months. The attributes of wheat root growth were little
affected by lime and gypsum (Table 3). Lime, when
incorporated into the soil, promoted roots with smaller
mean radius at the 10-20 cm depth, as compared to the
absence of liming and gypsum application. me rate appplied per year on the surface for 3 years. (2) full-rate lime on the surface in a single application. (1) 1/3 of the lime rate appplied per year on the surface for 3 years. (2) full-rate lime on the surface in a sing entia Agricola, v.59, n.2, p.357-364, abr./jun. 2002 , v.59, n.2, p.357-364, abr./jun. 2002 RESULTS AND DISCUSSION Table 1 - Changes in soil chemical traits for different depths, 23 months after the application of lim Lime and gypsum for wheat crop 361 of the root length was concentrated in the subsoil (20-60
cm). There was no water deficit during the crop cycle. Without water and nutrient restraints, the plant
concentrates its roots in the layers where growth is easier,
in order not to impair the absorption process (Marschner,
1986). The lack of response of the wheat root system to
the increase in exchangeable Ca in the subsoil layers must
be related to the low critical level values of the nutrient for
root growth (Ritchey et al., 1982). Moreover, low
concentrations of exchangeable Al were found in the
subsoil layers (2 to 5 mmolc dm
-3), despite the fact that the
chemical analysis results obtained prior to the installation
of the experiment revealed the presence of toxic Al (8
mmolc dm
-3). This decline in exchangeable Al in the subsoil
is likely to have occurred naturally by the presence of plant residue kept on the soil surface. Recent research
demonstrated a decrease in exchangeable Al in the soil
caused by plant material, and this is related to the increase
in pH and organic complexation (Miyazawa et al., 1993;
Franchini et al., 1999). Liming increased Mg concentration in wheat
leaves only when lime was incorporated into the soil
(Table 4), while the gypsum rates increased linearly leaf
concentrations of Ca and S. Caires et al. (1999) also
observed an increase in Mg concentration in wheat
leaves with liming, but Ca leaf concentration increased
only with the utilization of gypsum. The increase in the
concentration of S in wheat leaves brought by gypsum
was significantly related (P < 0.01) to the increase in
available S-SO4
2- in the soil at the six depths studied: 0- Scientia Agricola, v.59, n.2, p.357-364, abr/jun. 2002
Table 2 - Changes in soil chemical traits for different depths, 20 months after the application of gypsum rates. L = linear effect by polynomial regression. ns = non-significant, * = significant P < 0.05, ** = significant P < 0.01. RESULTS AND DISCUSSION Treatment
pH in
H+ + Al3+
Exchangeable Cations
Base
CaCl2
Ca2+
Mg2+
K+
Saturation
------------------------------- mmolc dm-3 ------------------------------
%
0-5 cm
No lime
4.8
80.6
53
17
6.7
49
Surface-applied lime (1 )
5.5
52.3
67
28
6.9
66
Surface-applied lime (2 )
5.7
49.2
72
29
6.7
69
Incorporated lime
5.6
44.6
63
26
7.2
68
LSD (P = 0.05)
0.3
8.2
13.6
8.4
1.7
5.8
CV (%)
4.3
10.3
15.1
23.4
17.7
6.5
5-10 cm
No lime
4.7
77.8
38
15
5.1
43
Surface-applied lime (1 )
5.1
61.8
44
24
5.0
54
Surface-applied lime (2 )
5.1
62.9
43
23
4.4
53
Incorporated lime
5.5
48.6
53
26
4.8
63
LSD (P = 0.05)
0.3
10.1
6.9
12.7
1.4
8.3
CV (%)
4.9
11.3
10.9
41.3
20.5
11.0
10-20 cm
No lime
4.5
82.2
27
14
3.6
35
Surface-applied lime (1 )
4.8
70.4
32
19
3.5
44
Surface-applied lime (2 )
4.8
69.8
32
18
2.9
43
Incorporated lime
5.1
58.2
38
24
3.2
53
LSD (P = 0.05)
0.2
8.9
7.8
7.4
1.3
8.6
CV (%)
3.5
9.0
16.9
27.4
28.9
13.9
20-40 cm
No lime
4.5
82.5
16
12
2.4
27
Surface-applied lime (1 )
4.5
79.1
19
14
2.3
31
Surface-applied lime (2 )
4.6
77.8
21
13
1.8
32
Incorporated lime
4.7
70.3
22
17
2.1
37
LSD (P = 0.05)
0.2
18.1
4.7
4.8
0.7
7.2
CV (%)
3.7
16.6
17.4
23.9
23.4
16.1
40-60 cm
No lime
4.5
74.9
11
10
1.9
23
Surface-applied lime (1 )
4.6
73.2
11
10
2.2
24
Surface-applied lime (2 )
4.6
68.6
14
12
1.4
29
Incorporated lime
4.7
67.1
17
14
2.2
33
LSD (P = 0.05)
0.2
8.5
4.9
3.6
1.0
5.8
CV (%)
2.4
8.5
25.5
19.6
38.6
14.4
60-80 cm
No lime
4.5
62.4
7
8
1.9
21
Surface-applied lime (1 )
4.6
63.1
7
9
2.0
22
Surface-applied lime (2 )
4.7
60.8
9
9
1.4
24
Incorporated lime
4.7
59.5
10
11
1.8
28
LSD (P = 0.05)
0.2
12.8
5.1
2.8
1.1
5.6
CV (%)
2.9
14.7
42.1
21.8
43.1
16.6 cal traits for different depths, 23 months after the application of liming treatments. t by polynomial regression. ns = non-significant, * = significant P < 0.05, ** = significant P < 0.01. ola, v.59, n.2, p.357-364, abr/jun. 2002 Scientia Agricola, v.59, n.2, p.357-364, abr/jun. 2002 L = linear effect by polynomial regression. ns = non-significant, * = significant P < 0.05, ** = significant Lime and gypsum for wheat crop Caires et al. Wheat grain yield was not significantly influenced
by the liming treatments. The mean yields were 3685,
3694, 3695 and 3602 kg ha
-1, respectively, for the
treatments without lime, split-rate lime on the surface, full-
rate lime on the surface, and incorporated lime. These
results are in agreement with those obtained in other 5 cm (r = 0.66), 5-10 cm (r = 0.69), 10-20 cm (r = 0.73),
20-40 cm (r = 0.72), 40-60 cm (r = 0.76) and 60-80 cm
(r = 0.64). The increases in S leaf concentrations were
directly related to the gains in availability of the nutrient
in the soil, assessed through extraction with ammonium
acetate 0.5 mol L
-1 in acetic acid 0.25 mol L
-1 (Figure 1). 3 - Wheat root growth traits for different soil depths as a function of lime and gypsum treatments. Table 3 - Wheat root growth traits for different soil depths as a function of lime and gypsum treatments. (1) full-rate lime on the surface in a single application. (2) 9 t ha-1 of surface-applied gypsum. Scientia Agricola, v.59, n.2, p.357-364, abr./jun. 2002 Scientia Agricola, v.59, n.2, p.357-364, abr./jun. 2002 RESULTS AND DISCUSSION 4
Treatment
pH in
H+ + Al3+
Exchangeable Cations
Base
CaCl2
Ca2+
Mg2+
K+
Saturation
t ha-1
------------------------------- mmolc dm-3 ------------------------------
%
0-5 cm
0
5.4
59.2
49
33
7.3
60
3
5.4
57.7
59
28
7.0
62
6
5.4
55.7
67
23
6.6
63
9
5.4
54.0
79
18
6.6
66
Effect
ns
ns
L**
L**
L**
L**
CV (%)
2.4
13.9
9.6
16.3
9.2
6.3
5-10 cm
0
5.1
62.3
34
28
5,0
52
3
5.1
63.2
42
24
5,0
53
6
5.1
63.8
48
19
4.7
53
9
5.1
61.5
54
16
4.7
55
Effect
ns
ns
L**
L**
L*
ns
CV (%)
3.3
11.4
11.1
16.6
10.8
7.9
10-20 cm
0
4.8
69,0
25
23
3.5
43
3
4.8
71.1
30
20
3.6
43
6
4.8
72.2
35
17
3.2
43
9
4.9
68.3
41
15
3.0
46
Effect
ns
ns
L**
L**
L**
ns
CV (%)
3.1
9.8
14.8
17.1
15.1
10.3
20-40 cm
0
4.6
72.7
14
14
2.4
29
3
4.6
78.7
16
15
2.1
30
6
4.6
78.4
21
15
2.0
33
9
4.6
80.0
26
13
1.9
34
Effect
ns
ns
L**
ns
L**
L*
CV (%)
3.1
11.2
14.1
19.5
21.5
14.5
40-60 cm
0
4.5
68.7
8
9
1.6
21
3
4.6
71.8
12
12
1.8
26
6
4.6
72.2
15
14
2.0
30
9
4.7
71.1
19
16
2.1
34
Effect
L**
ns
L**
L**
L*
L**
CV (%)
2.4
9.4
19.2
17.7
28.9
13.0
60-80 cm
0
4.5
59.3
6
7
1.3
19
3
4.6
62.0
7
8
1.8
21
6
4.6
62.1
9
9
2.0
24
9
4.7
62.3
12
11
1.9
29
Effect
L**
ns
L**
L**
L*
L**
CV (%)
2.5
8.6
22.1
20.1
30.6
13.3 Table 2 - Changes in soil chemical traits for different depths, 20 months after the application of gy il chemical traits for different depths, 20 months after the application of gypsum rates. Caires et al. 362 Caires et al. (1)1/3 of the lime rate appplied per year on the surface for 3 years. (2) full-rate lime on the surface in a single ap
polynomial regression. ns = non-significant, ** = significant P < 0.01. entia Agricola, v.59, n.2, p.357-364, abr./jun. 2002 Caires et al. According to the adjusted regression equation, the
maximum wheat yield would be reached at a gypsum rate
of 8.2 t ha
-1, corresponding to a yield increase of 420 kg
ha
-1. Very similar results were obtained in another trial
with the application of gypsum rates for corn (Caires et
al., 1999). The alterations that the application of gypsum to
the soil brings about are complex and their effects on
plants are difficult to be isolated. In soils with Al toxicity
in the subsurface layers, the improvement in growth and
the increase in wheat yield with the use of gypsum have
been related to the increase in the concentration of
sulfate in the subsoil solution, which causes an increase
in ionic force and a decrease in Al
3+ activity through the
establishment of the ionic pair AlSO4
+ (Mclay et al., 1994). Since in the present work Al levels were not very high,
this effect must not have been the most relevant. Figure 3 - Relation between relative wheat grain yield and soil S-
SO4
2- level, for the 0-20 cm layer, extracted by ammonium
acetate 0.5 mol L-1 in acetic acid 0.25 mol L-1. ** =
significant P < 0.01. Figure 2 - Wheat grain yield as a function of gypsum rates applied on
soil surface.* = significant P < 0.05. = 3.403,71 + 102,93x - 6,28x²
R² = 0,97*
0
3
6
9
0
3600
4000
3400
3800
^
Y
Wheat yield, kg ha
-1
Gypsum, t ha
-1
Relative yield, %
S-SO4
2-, mg dm
-3
0
30
60
90
120
150
70
80
90
100
Y = 96,26 - 161,78/x
r = - 0,69**
^
Critical level = 25.8 mg dm
-3 = 3.403,71 + 102,93x - 6,28x²
R² = 0,97*
0
3
6
9
0
3600
4000
3400
3800
^
Y
Wheat yield, kg ha
-1
Gypsum, t ha
-1 Figure 2 - Wheat grain yield as a function of gypsum rates applied on
soil surface.* = significant P < 0.05. Caires et al. (1)1/3 of the lime rate appplied per year on the surface for 3 years
(2) full-rate lime on the surface in a single application L = linear effect by
Treatment
N
P
K
Ca
Mg
S
--------------------------------------------------------------------- g kg -1 ---------------------------------------------------------------------
Liming
No lime
37.4
2.3
20.8
4.6
1.7
3.8
Surface-applied lime (1 )
37.3
2.4
21.4
5.1
2.2
4.1
Surface-applied lime (2 )
38.2
2.3
20.6
5.0
2.0
3.6
Incorporated lime
38.2
2.3
20.3
5.3
2.3
3.5
LSD (P = 0.05)
2.7
0.3
2.5
0.8
0.5
0.9
CV (%)
5.0
8.2
8.7
11.9
20.3
18.2
Gypsum, t ha-1
0
37.6
2.3
20.6
4.1
2.1
3.0
3
37.9
2.3
20.9
4.8
2.1
3.6
6
38.2
2.4
20.8
5.2
2.2
4.0
9
37.3
2.3
20.8
5.9
1.9
4.3
Effect
ns
ns
ns
L**
ns
L**
CV (%)
2.5
5.6
6.1
11.8
22.3
10.1 Lime and gypsum for wheat crop Lime and gypsum for wheat crop 363 reports (Pöttker & Ben, 1998; Caires et al., 1999) and
show that, in the absence of water deficit, it is possible
to achieve high wheat grain yield in acidic soils under a
no-tillage system, provided that exchangeable Ca and Mg
concentrations are sufficient and exchangeable Al levels
are not toxic. SO4
2- in the 0-20 cm layer caused by gypsum rates on
wheat yield. The critical level of soil S-SO4
2-, extracted
by ammonium acetate 0.5 mol L
-1 in acetic acid 0.25 mol
L
-1, was 25.8 mg dm
-3. Many doubts still exist regarding the
establishment of critical levels of S in the soil. Concentrations of 10 to 15 mg dm
-3 S-SO4
2- for the
extraction with ammonium acetate 0.5 mol L
-1 in acetic
acid 0.25 mol L
-1 have been proposed as critical levels,
considering results of studies conducted with several
crops (Malavolta et al., 1987 cited by Vitti, 1989). However, in order to achieve high wheat grain yields, it
is possible that the critical level of soil S-SO4
2- could be
higher. The importance of sulfate availability in the soil
stands out, especially during the grain filling stage,
considering that S is relatively immobile in the plant
(Eriksen et al., 2001). The application of gypsum rates increased wheat
grain yield and the response was quadratic (Figure 2). Caires et al. = 3.403,71 + 102,93x - 6,28x²
R² = 0,97*
0
3
6
9
0
3600
4000
3400
3800
^
Y
Wheat yield, kg ha
-1
Gypsum, t ha
-1 The positive and significant correlation (P < 0.05)
between leaf concentrations of S and wheat grain yield
(r = 0,61) indicates that there was a response of wheat
to the increase in soil S-SO4
2- concentrations owing to the
supply of sulfur by the gypsum. The relation between
relative yield and soil S-SO4
2- concentration (Figure 3)
shows the positive effect of the elevation of available S- Scientia Agricola, v.59, n.2, p.357-364, abr/jun. 2002
Figure 1 - Effect of gypsum rates, after 20 months, on soil S-SO4
2-
levels, extracted by ammonium acetate 0.5 mol L-1 in acetic
acid 0.25 mol L-1, for different depths. Figure 3 - Relation between relative wheat grain yield and soil S-
SO4
2- level, for the 0-20 cm layer, extracted by ammonium
acetate 0.5 mol L-1 in acetic acid 0.25 mol L-1. ** =
significant P < 0.01. Figure 2 - Wheat grain yield as a function of gypsum rates applied on
soil surface.* = significant P < 0.05. 0
3
6
9
0
Gypsum, t ha
-1
Relative yield, %
S-SO4
2-, mg dm
-3
0
30
60
90
120
150
70
80
90
100
Y = 96,26 - 161,78/x
r = - 0,69**
^
Critical level = 25.8 mg dm
-3
0
50
100
150
200
0
50
100
150
200
0
3
6
9
0
50
100
150
200
0
3
6
9
0 -5 cm
5 -1 0 cm
1 0 -2 0 cm
6 0 -8 0 cm
4 0 -6 0 cm
2 0 -4 0 cm
S-SO4
2-, mg dm-3
Gypsum (t ha
-1) Gypsum, t ha
-1 Figure 2 - Wheat grain yield as a function of gypsum rates applied on
soil surface.* = significant P < 0.05. yp
, Figure 2 - Wheat grain yield as a function of gypsum rates applied on
soil surface.* = significant P < 0.05. Figure 3 - Relation between relative wheat grain yield and soil S-
SO4
2- level, for the 0-20 cm layer, extracted by ammonium
acetate 0.5 mol L-1 in acetic acid 0.25 mol L-1. ** =
significant P < 0.01. Caires et al. T bl
4
N t i
t
t
ti
i
h
t l
f
ti
f li
d
t
Treatment
Root
Root
Mean
Relative
Density
Surface
Radius
Length
cm cm-3
cm2 cm-3
mm
%
0-10 cm
Control
2.56
0.239
0.15
50
Surface-applied lime (1 )
2.51
0.232
0.15
56
Gypsum (2)
2.71
0.261
0.15
53
Surface-applied lime (1) + Gypsum (2 )
2.56
0.258
0.16
55
Incorporated lime
2.62
0.241
0.15
55
LSD (P = 0.05)
2.31
0.225
0.04
19
CV (%)
31.6
32.4
8.7
13.0
10-20 cm
Control
0.60
0.069
0.19
13
Surface-applied lime (1 )
0.61
0.060
0.15
14
Gypsum (2)
0.69
0.068
0.15
14
Surface-applied lime (1) + Gypsum (2 )
0.54
0.054
0.16
12
Incorporated lime
0.67
0.056
0.13
14
LSD (P = 0.05)
0.51
0.055
0.04
11
CV (%)
29.3
31.6
9.6
30.0
20-40 cm
Control
0.54
0.049
0.14
21
Surface-applied lime (1 )
0.37
0.034
0.15
17
Gypsum (2)
0.49
0.045
0.15
18
Surface-applied lime (1) + Gypsum (2 )
0.49
0.046
0.15
21
Incorporated lime
0.32
0.029
0.14
14
LSD (P = 0.05)
0.36
0.034
0.03
8
CV (%)
29.2
29.9
7.6
15.6
40-60 cm
Control
0.43
0.037
0.13
17
Surface-applied lime (1 )
0.28
0.024
0.13
13
Gypsum (2)
0.40
0.038
0.14
15
Surface-applied lime (1) + Gypsum (2 )
0.39
0.025
0.14
12
Incorporated lime
0.40
0.034
0.13
18
LSD (P = 0.05)
0.36
0.037
0.04
13
CV (%)
33.7
41.5
10.6
30.6 Table 4 - Nutrient concentration in wheat leaves as a function of lime and gypsum rates. REFERENCES SUMNER, M.E.; SHAHANDEH, H.; BOUTON, J.; HAMMEL, J. Amelioration
of an acid soil profile through deep liming an surface application of gypsum. S il S i
S
i t
f A
i
J
l
50
1254 1278 1986 p
g
p
g
pp
gyp
Soil Science Society of America Journal, v.50, p.1254-1278, 1986. SYED-OMAR, S.R.; SUMNER, M.E. Effect of gypsum on soil potassium and
magnesium status and growth of alfafa. Communications in Soil Science
and Plant Analysis, v.22, p.2017-2028, 1991. EMPRESA BRASILEIRA DE PESQUISA AGROPECUÁRIA. Centro Nacional
de Pesquisa de Solos. Manual de métodos de análise de solo. 2.ed. Rio de Janeiro: EMBRAPA, CNPS, 1997. 212p. y
p
TENNANT, D. A test of a modified line intersect method of estimating root
length. Journal of Ecology, v.63, p.995-1001, 1975. ERIKSEN, J.; NIELSEN, M.; MORTENSEN, J.V.; SCHJORRING, J.K. Redistribution of sulphur during generative growth of barley plants with different
sulphur and nitrogen status. Plant and Soil, v.230, p.239-246, 2001. VITTI, G.C. Enxofre do solo. In: BÜLL, L.T.; ROSOLEM, C.A. (Ed.)
Interpretação de análise química de solo e planta para fins de
adubação. Botucatu: Fundação de Estudos e Pesquisas Agrícolas e
Florestais, 1989. p.129-173. FARINA, M.P.W.; CHANNON, P. Acid-subsoil amelioration. II. Gypsum effects
on growth and subsoil chemical properties. Soil Science Society of
America Journal, v.52, p.175-180, 1988. VITTI, G.C.; SUZUKI, J.A. A determinação do enxofre - sulfato pelo método
turbidimétrico. Jaboticabal: Universidade Estadual de São Paulo, 1978. 13p. FRANCHINI, J.C.; MALAVOLTA, E.; MIYAZAWA, M.; PAVAN, M.A. Alterações
químicas em solos ácidos após a aplicação de resíduos vegetais. Revista
Brasileira de Ciência do Solo, v.23, p.533-542, 1999. WEIR, C.C. Effect of lime and nitrogen application on citrus yields and on the
downward movement of calcium and magnesium in a soil. Tropical
Agriculture, v.51, p.230-234, 1975. p
HALLMARK, W.B.; BARBER, S.A. Root growth and morphology, nutrient
uptake and nutrient status of early grown soybeans as affected by soil P
and K. Agronomy Journal, v.76, p.209-212, 1984. g
WEIRICH NETO, P.H.; CAIRES, E.F.; JUSTINO, A.; DIAS, J. Correção da
acidez do solo em função de modos de incorporação de calcário. Ciência
Rural, v.30, p.257-261, 2000. WEIRICH NETO, P.H.; CAIRES, E.F.; JUSTINO, A.; DIAS, J. Correção da
acidez do solo em função de modos de incorporação de calcário. Ciência MALAVOLTA, E.; VITTI, G.C.; OLIVEIRA, S.A. Avaliação do estado
nutricional das plantas: princípios e aplicações. 2.ed. Piracicaba:
Associação Brasileira para Pesquisa da Potassa e do Fosfato, 1997. Caires et al. Relative yield, %
S-SO4
2-, mg dm
-3
0
30
60
90
120
150
70
80
90
100
Y = 96,26 - 161,78/x
r = - 0,69**
^
Critical level = 25.8 mg dm
-3 Figure 3 - Relation between relative wheat grain yield and soil
Relative yield, %
S-SO4
2-, mg dm
-3
0
30
60
90
120
150
70
80
90
100
Y = 96,26 - 161,78/x
r = - 0,69**
^
Critical level = 25.8 mg dm
-3 S-SO4
2-, mg dm
-3 Figure 3 - Relation between relative wheat grain yield and soil S-
SO4
2- level, for the 0-20 cm layer, extracted by ammonium
acetate 0.5 mol L-1 in acetic acid 0.25 mol L-1. ** =
significant P < 0.01. 4 Figure 1 - Effect of gypsum rates, after 20 months, on soil S-SO4
2-
levels, extracted by ammonium acetate 0.5 mol L-1 in acetic
acid 0.25 mol L-1, for different depths. Scientia Agricola, v.59, n.2, p.357-364, abr/jun. 2002 Scientia Agricola, v.59, n.2, p.357-364, abr/jun. 2002 364 Caires et al. OLIVEIRA, E.L.; PAVAN, M.A. Control of soil acidity in no-tillage system for
soybean production. Soil & Tillage Research, v.38, p.47-57, 1996. Wheat grain yield was also positively related (P
< 0.05) to the level of Ca (r = 0.50) and Ca/Mg ratio (r =
0.52) in the leaves. The increase in Ca concentration in
the solution reduces Mg concentration in the shoots, but
not in the roots, while the increase in Mg concentration
in the solution reduces Ca concentration in the wheat
roots and shoots by effect of ionic competition (Wheeler
& Edmeades, 1995). Thus, the increase in exchangeable
Ca and the movement of exchangeable Mg in the soil
brought by gypsum application may have promoted Ca
uptake by the plant, reflecting positively on wheat grain
yield. PAVAN, M.A.; BINGHAM, F.T.; PRATT, P.F. Toxicity of aluminum to coffee in
Ultisols and Oxisols amended with CaCO3 and CaSO4. Soil Science
Society of America Journal, v.46, p.1201-1207, 1982. Ultisols and Oxisols amended with CaCO3 and CaSO4. Soil Science
Society of America Journal, v.46, p.1201-1207, 1982. PAVAN, M.A.; BINGHAM, F.T.; PRATT, P.F. Redistribution of exchangeable
calcium, magnesium and aluminum following lime and gypsum applications
to a Brazilian Oxisol. Soil Science Society of America Journal, v.48,
p.33-38, 1984. PAVAN, M.A.; BLOCH, M.F.; ZEMPULSKI, H.C.; MIYAZAWA, M.; ZOCOLER,
D.C. Manual de análise química do solo e controle de qualidade. REFERENCES RAIJ, B. van; FURLANI, P.R.; GUAGGIO, J.A.; PETTINELLI JR., A. Gesso
na produção de cultivares de milho com tolerância diferencial a alumínio
em três níveis de calagem. Revista Brasileira de Ciência do Solo, v.22,
p.101-108, 1998. ANGHINONI, I.; SALET, R.L. Amostragem do solo e as recomendações de
adubação e calagem no sistema plantio direto. In: NUERNBERG, N.J. (Ed.) Conceitos e fundamentos do sistema plantio direto. Lages:
SBCS, Núcleo Regional Sul, 1998. p.27-52. p
REEVE, N.G.; SUMNER, M.E. Amelioration of subsoil acidity in Natal Oxisols
by leaching of surface applied amendments. Agrochemophysica, v.4,
p.1-6, 1972. CAIRES, E.F.; CHUEIRI, W.A.; MADRUGA, E.F.; FIGUEIREDO, A. Alterações
de características químicas do solo e resposta da soja ao calcário e gesso
aplicados na superfície em sistema de cultivo sem preparo do solo. Revista
Brasileira de Ciência do Solo, v.22, p.27-34, 1998. p
,
RITCHEY, K.D.; SILVA, S.E.; COSTA, V.F. Calcium deficiency in clayey B
horizons of savannah Oxisols. Soil Science, v.133, p.378-382, 1982. p
CAIRES, E.F.; FONSECA, A.F.; MENDES, J.; CHUEIRI, W.A.; MADRUGA,
E.F. Produção de milho, trigo e soja em função das alterações das
características químicas do solo pela aplicação de calcário e gesso na
superfície, em sistema de plantio direto. Revista Brasileira de Ciência
do Solo, v.23, p.315-327, 1999. SALET, R.L.; ANGHINONI, I.; FORNARI, T.G.; KRAY, C.H. O alumínio é menos
tóxico no sistema plantio direto. In: REUNIÃO SUL-BRASILEIRA DE
CIÊNCIA DO SOLO, 1., Lages, 1996. Resumos expandidos. Lages:
SBCS, Núcleo Regional Sul, 1996. p.72-74. CAIRES, E.F.; BANZATTO, D.A.; FONSECA, A.F. Calagem na superfície em
sistema plantio direto. Revista Brasileira de Ciência do Solo, v.24, p.161-
169, 2000. SOUSA, D.M.G.; RITCHEY, K.D. Uso de gesso no solo de cerrado. In:
SEMINÁRIO SOBRE O USO DE FOSFOGESSO NA AGRICULTURA, 1.,
Brasília, 1986. Anais. Brasília: EMBRAPA, DDT, 1986. p.119-144. Brasília, 1986. Anais. Brasília: EMBRAPA, DDT, 1986. p.1 CAIRES, E.F.; FONSECA, A.F. Absorção de nutrientes pela soja cultivada no
sistema de plantio direto em função da calagem na superfície. Bragantia,
v.59, p.213-220, 2000. SUMNER, M.E. Amelioration of subsoil acidity with minimum disturbance. In:
JAYAWARDANE, N.S.; STEWART, B.A. (Ed.) Subsoil management
techniques. Athens: Lewis Publishers, 1995. p.147-185. CARVALHO, L.J.C.B.; GOMIDE, R.L.; RODRIGUES, G.C.; SOUSA, D.M.G.;
FREITAS Jr., E. Resposta do milho à aplicação de gesso e déficit hídrico
em solos de cerrado. In: SEMINÁRIO SOBRE O USO DE FOSFOGESSO
NA AGRICULTURA, 1., Brasília, 1986. Anais. Brasília: EMBRAPA, DDT,
1986. p.61-83. Caires et al. Londrina: Instituto Agronômico do Paraná, 1992. 38p. (Circular, 76). PEARSON, R.W.; ABRUNA, F.; VICENTE-CHANDLER, J. Effect of lime and
nitrogen applications on downward movement of calcium and magnesium in
two humid tropical soils of Puerto Rico. Soil Science, v.93, p.77-82, 1962. Ö PÖTTKER, D.; BEN, J.R. Calagem para uma rotação de culturas no sistema
plantio direto. Revista Brasileira de Ciência do Solo, v.22, p.675-684,
1998. QUAGGIO, J.A.; RAIJ, B. van; GALLO, P.B.; MASCARENHAS, H.A.A. Respostas da soja à aplicação de calcário e gesso e lixiviação de íons no QUAGGIO, J.A.; RAIJ, B. van; GALLO, P.B.; MASCARENHAS, H.A.A. Respostas da soja à aplicação de calcário e gesso e lixiviação de íons no
perfil do solo. Pesquisa Agropecuária Brasileira, v.28, p.375-383, 1993. Scientia Agricola, v.59, n.2, p.357-364, abr./jun. 2002 REFERENCES 319p. WHEELER, D.M.; EDMEADES, D.C. Effect of varying solution calcium or
magnesium concentrations in the presence or absence of aluminum on
yield and plant calcium or magnesium concentrations in wheat. Journal
of Plant Nutrition, v.18, p.2229-2245, 1995. MARSCHNER, H. Mineral nutrition of higher plants. New York: Academic
Press, 1986. 403p. of Plant Nutrition, v.18, p.2229-2245, 1995. ZIGLIO, C.M.; MIYAZAWA, M.; PAVAN, M.A. Formas orgânicas e inorgânicas
de mobilização do cálcio no solo. Brazilian Archives of Biology and
Technology, v.42, p.257-262, 1999. MCLAY, C.D.A.; RITCHIE, G.S.P.; PORTER, W.M.; CRUSE, A. Amelioration
of subsurface acidity in sandy soils in low rainfall regions. 2. Changes to
soil solution composition following the surface application of gypsum and
lime. Australian Journal of Soil Research, v.32, p.847-865, 1994. p
g
pp
gyp
lime. Australian Journal of Soil Research, v.32, p.847-865, 1994. MIYAZAWA, M.; PAVAN, M.A.; CALEGARI, A. Efeito de material vegetal na
acidez do solo. Revista Brasileira de Ciência do Solo, v.17, p.411-416,
1993. Received August 20, 2001 Scientia Agricola, v.59, n.2, p.357-364, abr./jun. 2002
|
https://openalex.org/W2102557765
|
https://europepmc.org/articles/pmc2914652?pdf=render
|
English
| null |
Bone mineral density in partially recovered early onset anorexic patients - a follow-up investigation
|
Child and adolescent psychiatry and mental health
| 2,010
|
cc-by
| 10,425
|
Abstract Background and aims: There still is a lack of prospective studies on bone mineral development in patients with a
history of early onset Anorexia nervosa (AN). Therefore we assessed associations between bone mass accrual and
clinical outcomes in a former clinical sample. In addition to an expected influence of regular physical activity and
hormone replacement therapy, we explored correlations with nutritionally dependent hormones. Methods: 3-9 years (mean 5.2 ± 1.7) after hospital discharge, we re-investigated 52 female subjects with a history
of early onset AN. By means of a standardized approach, we evaluated the general outcome of AN. Moreover, Methods: 3-9 years (mean 5.2 ± 1.7) after hospital discharge, we re-investigated 52 female subjects with a history
of early onset AN. By means of a standardized approach, we evaluated the general outcome of AN. Moreover,
bone mineral content (BMC) and bone mineral density (BMD) as well as lean and fat mass were measured by dual-
energy x-ray absorptiometry (DXA). In a substudy, we measured the serum concentrations of leptin and insulin-like
growth factor-I (IGF-I). Results: The general outcome of anorexia nervosa was good in 50% of the subjects (BMI ≥17.5 kg/m2,
resumption of menses). Clinical improvement was correlated with BMC and BMD accrual (c2 = 5.62/c2 = 6.65, p =
0.06 / p = 0.036). The duration of amenorrhea had a negative correlation with BMD (r = -.362; p < 0.01), but not
with BMC. Regular physical activity tended to show a positive effect on bone recovery, but the effect of hormone
replacement therapy was not significant. Using age-related standards, the post-discharge sample for the substudy
presented IGF-I levels below the 5th percentile. IGF-I serum concentrations corresponded to the general outcome
of AN. By contrast, leptin serum concentrations showed great variability. They correlated with BMC and current
body composition parameters. Conclusions: Our results from the main study indicate a certain adaptability of bone mineral accrual which is
dependent on a speedy and ongoing recovery. While leptin levels in the substudy tended to respond immediately
to current nutritional status, IGF-I serum concentrations corresponded to the individual’s age and general outcome
of AN. completed around the age of 20 at least - may not be
reached. Alterations in bone microarchitecture and per-
sistent bone mineral deficiencies can follow, increasing
the risk of osteoporotic fractures [2,3]. Lean body mass
is a surrogate for muscle mass. * Correspondence: ulrike.schulze@uniklinik-ulm.de
1Department of Child and Adolescent Psychiatry/Psychotherapy, University of
Ulm, Germany © 2010 Schulze et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons
Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in
any medium, provided the original work is properly cited. RESEARCH Open Access Open Access Abstract While the nutrition-
exercise-bone mass relationship in general is said to be
complex, the enhancement of lean mass from long-term
sports participation during adolescence results in greater
bone mass accrual in healthy individuals [4]. Mechanical
forces have been described as a factor in regulating
bone modeling [5]. Bone mineral density in partially recovered early
onset anorexic patients - a follow-up
investigation Ulrike ME Schulze1*, Simone Schuler2, Dieter Schlamp4, Peter Schneider3, Claudia Mehler-Wex Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Background Anorexia nervosa (AN) is an illness with major psychia-
tric and physical components - not simply a psychiatric
condition - with a high risk of chronicity, complications,
and adverse long-term effects. During childhood and
adolescence, its specific psychopathology occurs at criti-
cal periods for bone growth and mineral accrual [1]. Mediated by nutritional deficits and hormonal
abnormalities, peak bone mass - which should be Deficient bone accrual is not limited to the acute
phase of illness or the most severe stage of malnutrition. Page 2 of 11 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 The linearity of association with disease duration and its
mechanism are debated. Some authors suggest that ado-
lescent AN shows a decreased bone turnover overall, in
contrast to postmenopausal osteoporosis in which
uncoupling of bone turnover is found, i.e. markers of
increased bone resorption and decreased bone formation
[6-10]. achieve normal longitudinal bone growth and bone
mass. In adults, they are essential for bone maintenance
[5]. The IGF-I present in the systemic circulation,
synthesized by peripheral tissues, and expressed by
osteoblasts regulates bone size, shape, and composition. Moreover, it plays a key role in adapting an individual’s
bone structure to mechanical loads during growth and
development [5,25]. The linearity of association with disease duration and its
mechanism are debated. Some authors suggest that ado-
lescent AN shows a decreased bone turnover overall, in
contrast to postmenopausal osteoporosis in which
uncoupling of bone turnover is found, i.e. markers of
increased bone resorption and decreased bone formation
[6-10]. In premenopausal women, BMD determination alone
is not adequate for assigning the labels “osteopenia” and
“osteoporosis” (as per WHO guidelines). Thus, in this
age group, labeling of changes should use terms like
“poor bone mass accumulation” or “reduced bone
mass”. Furthermore, patients themselves may be better
controls for follow-up examinations than age- and sex-
matched healthy individuals [11]. In patients with AN, abnormalities in the GH/IGF-I axis
have a critical impact on the development of osteoporosis
[5]. IGF-I as a nutritionally dependent bone trophic factor
may be regarded as the major correlate of bone formation. Its serum concentration improves with weight gain: body
mass index (BMI) is reported to show a positive correla-
tion with free IGF-I. Expectations We assumed a positive influence on bone mass develop-
ment due to hormonal substitution, and we furthermore
expected that moderate regular physical activity would
have a positive effect on bone mineral density [27]. The IGF/IGF binding protein (IGFBP) system is
known to be an essential component in the hormonal
regulation of longitudinal growth. GH and IGF-I are
involved in bone modeling and remodeling during child-
hood and adolescence; they are important regulators of
bone homeostasis and one of the factors required to Hypotheses Because of the young age of our former patients and
early manifestation of their restrictive AN, we hypothe-
sized that bone mineral accrual would be comparatively
deficient. We also postulated that a good global out-
come and weight gain outcome would be able to coun-
teract bone mineral loss. Aims The aims of our follow-up investigation were to assess
the outcome of early onset AN, and its hormonally
related effects on bone mineral parameters and their
relation to lean body mass. Background By contrast, independent of BMI,
endogenous IGF-I, leptin, and androgen levels are sug-
gested to predict bone microarchitecture [3]. Recovery of bone mineral density (BMD) in AN is
described as a slow process [12]; it is a product of com-
plex interactions between hormonal and nutritional fac-
tors [11]. Recent data suggest that bisphosphonates are
effective in anorexic females [13]. However, at this stage,
great caution is advised and - especially in premenopau-
sal women - bisphosphonate use should be limited to
clinical trials. This also applies to estrogen therapy in
young women with AN because of the methodological
problems and application technology involved. The
results of different trials so far provide rather limited
evidence [11,14,15]. Early detection of the illness and
normalization of weight and menses are believed to be
essential [16]. Follow-up studies on BMD in anorexic patients with
onset in childhood and adolescence are rare [26-29];
post-discharge histories in most cases are short or show
great variation [30-33]. In particular, there still is a lack
of prospective studies in this patient group. Despite the
possibility of improving BMD in the long term [34],
comparatively little is known about the effect of the gen-
eral outcome of AN on bone accrual and hormonal cor-
relations - especially with a view on former patients
with an early onset of illness. Hormonal changes which
lead to a normalization of essential bodily functions (e.g. resumption of menses) cannot be predicted by one spe-
cific (laboratory) parameter. Leptin plays a key part in energy homeostasis [17]. Its
serum levels correlate with body fat mass (FBM) and
body mass index (BMI) both in healthy individuals [18],
and in patients with AN [19]. In this patient group,
weight loss-associated hypoleptinemia reflects both
somatic and behavioral adaptations to starvation. The
hormone also produces anorexigenic effects in the brain. It modulates the mesolimbic dopamine system via speci-
fic inhibitory neurons in the lateral hypothalamic area,
decreasing feeding and body weight [20,21]. Secreted by
fat cells and linking changes in body composition with
bone formation and bone resorption, the cytokine-like
hormone acts through its direct anabolic effects on
osteoblasts and also through central effects (e.g. stimula-
tion of the GH-IGF-1 axis, stimulation of beta2-adrener-
gic receptors, suppression of neuropeptide Y) [22,23]. However, we should note that both in-vitro or animal
studies and human cross-sectional studies on the role of
leptin in bone metabolism are not conclusive [24]. Methods We classified the extent of eating disorder symptomatol-
ogy in accordance with generally accepted clinical Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Page 3 of 11 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 the baseline values of the nutritionally dependent
hormones. outcome criteria [35-37]. As well, we expected baseline
and follow-up data concerning BMD, bone mineral con-
tent (BMC), and the soft tissue composition of lean and
fat body mass (LBM, FBM) to be related to clinical
outcome. The initial DXA measurement (t1) was performed
within four weeks of admission. At follow-up (t2), cur-
rent body composition was compared with baseline, and
to provide comparability with previous studies of our
study group [39,40], the same reference data were used
[41-44]. In terms of an explorative substudy, we additionally
estimated to see some association with serum leptin
concentrations and IGF-I. At follow-up, the outcome criteria included the cur-
rent body mass index, presence or absence of menstrual
cycle, and/or bulimia nervosa (see Table 2). The general
outcome resulting from these factors (predominantly
physical parameters, but also bulimic symptoms in cases
of poor outcome) was defined according to the criteria
of Morgan and Russell, modified by Ratnasuriya [35-37]. Hormone replacement therapy was assumed if estro-
gens had been taken without interruption for at least
12 months before follow-up. At follow-up, the outcome criteria included the cur-
rent body mass index, presence or absence of menstrual
cycle, and/or bulimia nervosa (see Table 2). The general
outcome resulting from these factors (predominantly
physical parameters, but also bulimic symptoms in cases
of poor outcome) was defined according to the criteria
of Morgan and Russell, modified by Ratnasuriya [35-37]. Main Study
Participants From an original sample of 103 inpatients, we reinvesti-
gated BMD, BMC, LBM and FBM in 52 subjects (sam-
ple 1; for descriptive statistics see Table 1). Two of the
former patients had died. A statistical comparison
between participants and refusing individuals on age,
duration of follow-up, BMI, duration of amenorrhea,
BMD, BMC, LBM and FBM showed no significant dif-
ferences except in the duration of amenorrhea before
admission (5 months in participants vs. 8 months in
refusing individuals). At follow-up, 23 individuals under-
went an estrogen substitution, two of them less than
12 months. Hormone replacement therapy was assumed if estro-
gens had been taken without interruption for at least
12 months before follow-up. Participants who had exercised consistently for at least
9 months during the follow-up period were classified as
physically active. Instruments The specific eating disorder psychopathology at follow-
up was assessed using a clinical semi-structured inter-
view and the CIDI [45]. These instruments allowed the
classification of specific symptoms and their severity in
cases of persistence or manifestation of an eating dis-
order (anorexic or bulimic symptoms). The patients, consecutively admitted, were reexamined
by the first two authors after a post-discharge period of
5.2 years (± 1.7; range 3-9 years). All individuals met the
DSM-IV diagnostic criteria for AN (restrictive subtype)
upon admission [38]. Most of the patients had been hos-
pitalized initially for AN. Male patients were excluded
because of the small number of patients and the effects
of hormones on bone development. There were no addi-
tional inclusion or exclusion criteria. Physical examination All participating patients underwent a physical examina-
tion to ensure an overall physical assessment. Laboratory tests Procedures In addition to the physical examination, we carried out a
laboratory assessment using commercially available tests
for the blood count, electrolyte balance, and pancreatic,
liver, kidney, thyroid and gonadal function. The study was reviewed by the appropriate institutional
review board. All patients gave informed consent prior
to their inclusion into the study. We did not measure Bone and lean body mass parameters Bone and lean body mass parameters Dual-energy x-ray absorptiometry (DXA, LUNAR
DPX-L, Lunar Corporation, Madison, USA) was used
to perform whole body scans. These scans recorded
the total body mineral content BMC [kg], BMC pro-
jected on bone area (which is commonly defined as
BMD [g/cm2]), lean body mass LBM [kg], and fat mass
FBM [kg]. Generally, BMD depends on the bone area
projected on a plane. Bone area adds a blurring para-
meter to bone mineral content as the primary DXA
finding. Table 1 Sample description
Main study/sample 1 (n = 52)
mean
SD
min
max
Follow-up period (years)
5.23
1.69
3
9
Age (t1/years)
15.51
2.07
9.83
18.83
Age (t2/years)
20.78
2.72
12.80
26.70
BMI (t1)
14.74
1.88
10.42
18.67
BMI (t2)
20.13
2.79
14.26
28.14
Sub study/sample 2 (n = 39)
mean
SD
min
max
Follow-up period (years)
5.26
1.71
3
9
Age (t1/years)
15.47
2.10
9.83
18.83
Age (t2/years)
20.72
2.79
12.80
25.50
BMI (t1)
14.88
1.86
14.87
18.67
BMI (t2)
19.91
2.52
14.30
26.30 Bone and lean body mass parameters For the entire post-discharge sample (n = 52), all essential
body composition and bone mineralization parameters
(FBM, LBM, BMC, BMD) exhibited a considerable accrual
(Table 4). An association between the differences and gen-
eral outcome of AN was shown (Table 5). BMC z-score
changes are illustrated in Table 6. Participants A subgroup of 39 participants (sample 2) also agreed to
give an additional blood sample at follow-up (for
descriptive statistics of both samples see Table 1). N
i i
ll
d
d
h In the general physical examination, 35% of the former
patients showed dermatologic signs of AN such as acro-
cyanosis or lanugo hairs. Tanner stages were appropriate
for the individual age. We determined the serum levels of IGF-I, and leptin by
in-house radioimmunoassays, described previously
[18,46-49]. IGF-I was measured by IGFBP-blocked assay
in the presence of a large excess of IGF-I to inhibit the
interference of binding proteins. The serum was always
obtained in the morning. Analysis Analysis Spearman’s correlation coefficients were calculated
between serum leptin levels and IGF-I, and BMD, BMC
or body composition (FBM, LBM) changes. g
Analysis Lean body mass of our patients
increased from 34 (± 5) to 39 (± 4) kg during the post-
discharge period. General outcome of AN 50% (n = 26) of the post-discharge sample presented a
good general outcome (Table 2). At follow-up, 6 indivi-
duals (11.5%) suffered from anorexia or bulimia nervosa. Duration of amenorrhea considerably differed (13-32
months; Table 2). Detailed information concerning our
former patients with a poor outcome is given on Table 3. Physical examination g
Analysis Statistical analysis was made using SPSS™. Student’s
t-test for dependent samples was used for the bone
mineral parameters. The Kruskal-Wallis test was applied
to differentiate between the three outcome groups
(good, intermediate, and poor outcome), while allowing
for the small sample size. We used the Mann-Whitney Page 4 of 11 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Table 2 General outcome - sample 1 (n = 52)
Outcome
n
(%)
BMI U1
(kg/m2)
BMI U2
(kg/m2)
amenorrhea
(months)
Good
(BMI ≥17.5; regular menstrual cycle)
26 (50.0%)
14.9 (± 1.9)
20.5 (± 2.2)
13 (± 15)
Intermediate
(BMI < 17.5 or BMI > 26; or irregular menstrual cycle/fluctuations of weight, amenorrhea)
20 (38.5%)
15.1 (± 1.9)
20.6 (± 3.0)
32 (± 27)
Poor
(BMI < 17.5; amenorrhea; bulimic symptoms)
6 (11.5%)
13.1 (± 1.9)
17.1 (± 2.6)
27 (± 16) Table 2 General outcome - sample 1 (n = 52) Table 2 General outcome - sample 1 (n = 52)
Outcome (± 2.1; range 10-19) and 20.8 years (± 2.8; range 13-26) at
follow-up. test for the differences between any two groups. The
significance level was set at: *: p < 0.05; **: p < 0.001. The Least Significance Difference group test (LSD) for
unequal (and small) sample sizes was used to test group
range differences in the BMC z-score changes, as well as
changes in the ratio of BMC/LBM. The significance
level was set at p < 0.05. The z-scores were calculated
using a polynomial fit function based on the means and
standard deviations of the normal BMC values from
Zanchetta et al. [44]. test for the differences between any two groups. The
significance level was set at: *: p < 0.05; **: p < 0.001. The Least Significance Difference group test (LSD) for
unequal (and small) sample sizes was used to test group
range differences in the BMC z-score changes, as well as
changes in the ratio of BMC/LBM. The significance
level was set at p < 0.05. The z-scores were calculated
using a polynomial fit function based on the means and
standard deviations of the normal BMC values from
Zanchetta et al. [44]. Mean BMI had increased from 14.7 kg/m2 (± 1.9) to
20.1 kg/m2 (± 2.8). Laboratory tests A low-T3 syndrome was found in 8 patients; 2 partici-
pants suffered from hypothyroidism; in 19 cases, a slight
increase of amylase was observed. There were no further
pathological findings. * Hormone resp. estrogen substitution at follow-up Correlations The duration of amenorrhea correlated negatively with
BMD (r = –.362; p < 0.01). While regular physical activ-
ity tended to result in a gain only of BMD (– 0.063
(± 0.07) compared with 0.028 (± 0.07)), BMC showed a
positive correlation with regular work-outs. Hormone
replacement did not have a distinct influence on bone
development (Table 7). Unlike the significant group dif-
ferences in BMD baseline values (t1), the differences at
follow up did not reach statistical significance. The z-score changes in BMC values were significantly
different among the three outcome groups (good vs. poor: p = 0.02; figure 1), whereas LBM accrual showed
no significant differences. However, the ratio of BMC to
LBM changes was significantly different between the
three outcome groups (good vs. intermediate: p < 0.05,
good vs. poor: p < 0.02; figure 2). At follow up, the
BMC to LBM ratio had not changed in the good and
intermediate group over time, but there was a significant
deficiency in BMC accrual in the poor outcome group
(p < 0.05, Table 5). Hormone replacement 32 patients reported taking hormone Tablets - predomi-
nantly in the form of contraceptives - for at least 12
months. Effects of hormone replacement therapy are
given in Table 7. Physical activity The 39 participants who agreed to an additional blood
taking were classified as follows: 20 (51.3%) showed a
“good” outcome, whereas 15 (38.5%) individuals had an
“intermediate”, and 4 (10.3%) a “poor” general outcome
according to the Morgan and Russell method, modified
by Ratnasuriya [35-37]. A single sport or various kinds of sports (9-month
minimum) were reported by 26 (50%) of the re-investi-
gated individuals. Of these, 23 had a BMI ≥17.5 kg/m2
at follow up. There was no significant association
between regular physical activity and weight restora-
tion (BMI ≥17.5 kg/m2) (c2 = 0.165; df = 1; p = 0.69). While 16 out of 26 (61.5%) participants with a good
outcome reported that they worked out regularly, 13
of 20 (65%) individuals with an intermediate outcome
did not (c2 = 3.185; df = 2; p = 0.20). Merging both Results Follow-up examinations were performed 5.2 years
(± 1.7; range 3-9 years) after discharge. The median age
of our patients at time of first examination was 15.5 years Table 3 Detailed information concerning the patients with a poor outcome - sample 1 (n = 52)
Individual Person
Follow-up period
years
Age (t2)
(years)
BMI (t1)
(kg/m2)
BMI (t2)
(kg/m2)
amenorrhea
(months)
Binging/purging
A
4
19.5
14.5
16.4
14
yes
B
3
20.6
10.8
22.1
24
yes
C
4
19.5
12.8
16.6
36*
no
D
4
20.3
12.5
14.3
32*
no
E
3
19.5
13.9
17.0
4*
no
F
7
21.7
14.4
16.5
50
yes Table 3 Detailed information concerning the patients with a poor outcome - sample 1 (n = 52) Page 5 of 11 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Table 4 Body composition and bone parameters at first
examination (t1) and follow-up (t2) - sample 1 (n = 52) Table 4 Body composition and bone parameters at first
examination (t1) and follow-up (t2) - sample 1 (n = 52)
Parameter
t 1
t 2
Fat Body Mass (FBM) (%)
12 (± 7)
25 (± 8)*
Lean Body Mass (kg)
34 (± 5)
39 (± 4)*
Bone Mineral Content (kg)
2.04 (± 0.34)
2.37 (± 0.32)*
Bone Mineral Density (g/cm2)
1.04 (± 0.08)
1.09 (± 0.07)*
*p < 0.001 (t-test for dependent samples) groups to compare them as one with the poor out-
come group, did not reveal any statistically relevant
differences. Nutritionally dependent hormones Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Page 6 of 11 Table 6 BMC z-score-changes and differences according
to the general outcome and in relation to each other
(Least Significance Difference Group Test) - sample 1
(n = 52)
Outcome
BMC z-core according to the
outcome
Good
M =
.399
Intermediate
M = .166
Poor
M =
.166
Good
0.32
0.02
Intermediate
0.32
0,11
Poor
0.02
0.11 Table 6 BMC z-score-changes and differences according
to the general outcome and in relation to each other
(Least Significance Difference Group Test) - sample 1
(n = 52) symptoms had changed to binge eating with
sponding weight gain of 15 kg over 2 months). Using age-related standards (Blum, 1996) to
mean values of insulin-like growth factors and i
proteins, IGF-I levels below the 5th percentile we
Table 8 shows the analyzed bone and body
tion parameters according to outcome group. kal-Wallis test revealed significant difference
the groups in BMD (p = 0.03), BMC (p =
IGF-I (p = 0.02). In terms of trend, a better
group status resulted in higher BMD, BMC
values. Correlations
Correlations were found between serum lepti
trations and current body composition parame
relations between physical status and serum
parameters at follow-up are given in Table 9
cally, there were significant correlations betw
and BMI, leptin and BMC, and leptin and FB
over, correlations were found between LBM
and LBM and BMC. Discussion
Along with assessment of the general outco
former anorexic inpatients, we tracked th
Table 6 BMC z-score-changes and differences ac
to the general outcome and in relation to each
(Least Significance Difference Group Test) - sam
(n = 52)
Outcome
BMC z-core according to the
outcome
Good
M =
.399
Intermedia
M = .166
Good
0.32
Intermediate
0.32
Poor
0.02
0.11
Figure 1 BMC z-score changes differentiating betw
groups. Figure 2 Differences in the ratio of bone mineral mass and
lean body mass at follow-up. symptoms had changed to binge eating with a corre-
sponding weight gain of 15 kg over 2 months). Using age-related standards (Blum, 1996) to assign the
mean values of insulin-like growth factors and its binding
proteins, IGF-I levels below the 5th percentile were found. Figure 2 Differences in the ratio of bone mineral mass and
lean body mass at follow-up. Table 8 shows the analyzed bone and body composi-
tion parameters according to outcome group. Correlations In agreement with other follow-up studies [50-52], we
found a good general outcome after 5.3 years in half of
the post-discharge group (Table 2). Correlations were found between serum leptin concen-
trations and current body composition parameters. Cor-
relations between physical status and serum and bone
parameters at follow-up are given in Table 9. Specifi-
cally, there were significant correlations between leptin
and BMI, leptin and BMC, and leptin and FBM. More-
over, correlations were found between LBM and BMI,
and LBM and BMC. At first glance and conditionally contrary to our initial
expectations, bone mineral accrual was positive over the
entire post-discharge sample (Table 4). More explicitly
considered - and this was replicated in other studies -
clinical improvement correlated positively with both
BMC and BMD [28,53]. A good outcome of AN was associated with a small
increase in BMC z-scores (Figure 1). This is of some
importance, because results of a previous study on the
body composition of 31 anorexic adolescent girls
demonstrated that BMC reflects the bone/muscle rela-
tionship better than BMD [39]. A poor outcome seems
to be associated with a tendency toward bone loss. In
spite of a possible catch-up effect associated with a good
short-term outcome [31] and a long-term absence of
clinically relevant symptoms of AN, complete normali-
zation of BMD cannot be necessarily expected [33]. Nutritionally dependent hormones The Krus-
kal-Wallis test revealed significant differences between
the groups in BMD (p = 0.03), BMC (p = 0.03) and
IGF-I (p = 0.02). In terms of trend, a better outcome
group status resulted in higher BMD, BMC and IGF-I
values. mineral development in a follow-up investigation. We
also investigated possible interactions between bone
mineral parameters and nutritionally dependent hor-
mones (leptin, IGF-I) in a subgroup of 39 individuals to
test the possible impact of nutritional status on bone
development. Nutritionally dependent hormones Serum leptin levels varied from 1.48 μg/l (the BMI of
this patient was 17.2 kg/m2 over several years) to 43.1
μg/l (correlated with a current BMI of 22.1 kg/m2 - this
patient had been anorectic for years and her current Table 5 Bone mineral mass and body composition (means/SD) according to the general outcome - sample 1 (n = 52),
p-values refer to a t-test for dependent samples and indicate differences between first examination and follow-up Table 5 Bone mineral mass and body composition (means/SD) according to the general outcome - sample 1 (n = 52),
p-values refer to a t-test for dependent samples and indicate differences between first examination and follow-up
Outcome
good
n = 26
intermediate
n = 20
poor
n = 6
BMI (kg/m2)
20.5 (± 2.2)
20.6 (± 3.0)
17.1 (± 2.6)
FBM (%)
27 (± 8)**
p < 0.001 (+)
25 (± 8)**
p < 0.001 (+)
19 (± 7)*
p = 0.021 (+)
Δ FBM (Mean/SD)
0.13 (± 0.10)
0.11(± 0.07)
0.12 (± 0.10)
LBM (kg)
39 (± 5)**
p < 0.001 (+)
39 (± 3)*
p = 0.001 (+)
36 (± 4)
p = 0.062 (+)
Δ LBM (Mean/SD)
4.94 (± 6.5)
3.90 (± 3.48)
4.27 (± 4.28)
BMD (g/cm2)
1.10 (± 0.07)**
p = 0.000 (+)
1.09 (± 0.06)
p = 0.050 (+)
1.02 (± 0.08)
p = 0.125 (-)
Δ BMD (Mean/SD)
0.08 (± 0.07)
0.02 (± 0.05)
-0.03 (± 0.04)
BMC (kg)
2.43 (± 0.30)**
p < 0.001 (+)
2.38 (± 0.3)**
p <0.001 (+)
2.04 (± 0.3)
p = 0.872 (+)
Δ BMC (Mean/SD)
0.08 (± 0.07)
0.02 (± 0.05)
-0.05 (± 0.04)
BMC/LBM (at follow-up)
0.062 (± 0.008)
p = 0.15
0.060 (± 0.007)
p = 0.53
0.054 (± 0.004)*
p < 0.05
Δ BMC/LBM (Mean/SD)
-0.003 (± 0.008)
-0.001 (± 0.008)
+0.007 (± 0.004)
+ = increase, - = decrease
* p < 0.05; ** p < 0.001 Table 5 Bone mineral mass and body composition (means/SD) according to the general outcome
p-values refer to a t-test for dependent samples and indicate differences between first examinati eral mass and body composition (means/SD) according to the general outcome - sample 1 (n = 52)
t-test for dependent samples and indicate differences between first examination and follow-up Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Schulze et al. Discussion Along with assessment of the general outcome of 52
former anorexic inpatients, we tracked their bone Figure 1 BMC z-score changes differentiating between three
groups. Weight restoration and resumption of menses both
are known to be the most important preconditions for
bone recovery [16]. In particular, the results of a pro-
spective observational study on 34 girls with AN (aged
12-18 years) revealed that the recovery of menses is an
essential pre-condition for stabilization of BMD mea-
sures [28]. In anorexic individuals, weight gain represents a sig-
nificant and independent predictor of BMD, whereas
adipose tissue is suggested to play a substantial role in Figure 1 BMC z-score changes differentiating between three
groups. Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Page 7 of 11 Table 7 Effects of hormone replacement at follow-up (Mean/SD), p-values refer to a t-test for dependent samples and
indicate differences between first examination (t1) and follow-up (t2) - sample 1 (n = 52)
BMD
(g/cm3)
BMC
(kg)
LBM
(kg)
FBM
(%)
Hormone replacement
1.10 (± 0.06)
p < 0.001 (+)
2.40 (± 0.3)
p < 0.001(+)
39 (± 5)
p < 0.001(+)
26 (± 9)
p < 0.001(+)
Without substitution
1.06 (± 0.07)
p = 0.028 (+)
2.31 (± 0.4)
p = 0.001 (+)
39 (± 4)
p < 0.001(+)
25 (± 6)
p < 0.001(+)
p-level
0.06
0.33
0.96
0.65 Table 7 Effects of hormone replacement at follow-up (Mean/SD), p-values refer to a t-test for dep
indicate differences between first examination (t1) and follow-up (t2) - sample 1 (n = 52) mone replacement at follow-up (Mean/SD), p-values refer to a t-test for dependent samples and
etween first examination (t1) and follow-up (t2) - sample 1 (n = 52) the recovery of menstruation cycles (due to co-enabling
ot a hormonal “reset”) and weight-related protective
effects on bone [54]. In our sample, fat mass revealed a
significant increase, and the duration of amenorrhea
correlated negatively with BMD, but not with BMC. Though, weight gain alone appears not to be sufficient
to explain any increases in BMD. In a re-investigation of
a small sample of anorexic adult patients, Baker et al. [55] showed that behavioral factors such as vomiting,
nicotine and alcohol intake also may predict a reduction
of BMD. Discussion adolescence revealed a restrictive eating disorder at fol-
low-up (six years after initial assessment) as the stron-
gest predictor of low BMD, whereas a BMI > 22 and
high physical activity appeared to be the most important
counter-indicators [32]. Particularly with regard to bed
rest, a pilot study on patients aged 13-21 years showed
that limitation of physical activity during hospitalization
for patients with AN is associated with suppressed bone
formation and resorption and an imbalance in bone
turnover [61]. These results agree with those on BMD
in male adolescents with AN. A follow-up study on 20
patients revealed that < 3 hours/week of physical activity
correlated strongly with osteopenia [62]. the recovery of menstruation cycles (due to co-enabling
ot a hormonal “reset”) and weight-related protective
effects on bone [54]. In our sample, fat mass revealed a
significant increase, and the duration of amenorrhea
correlated negatively with BMD, but not with BMC. Though, weight gain alone appears not to be sufficient
to explain any increases in BMD. In a re-investigation of
a small sample of anorexic adult patients, Baker et al. [55] showed that behavioral factors such as vomiting,
nicotine and alcohol intake also may predict a reduction
of BMD. Amenorrhea in this patient group is thought to be an
adaptive response to an energy deficit, partially mediated
by leptin. As treatment with estrogen replacement ther-
apy does not reverse the bone loss, the administration
of recombinant leptin in order to restore LH pulsatility
and ovulatory menstrual cycle may be worth considering
prospectively [56] - but cautiously because of its anor-
exigenic effects [20,21]. On the other hand, in our sam-
ple as in several other studies, hormone replacement
therapy did not show a distinct effect on bone mineral
development [57,58]. In this context, lean mass may have a functional
impact. There are rare findings that the ratio between
lean body mass and bone mineral mass accrual (BMC/
LBM) is also compromised [63]; BMC/LBM curves
always correlate linearly. Multiple regression tests have
shown little or no independent interaction of body
weight or height with those relationships [64]. In a study on 24 adolescent patients with AN, Wong
et al. found significant correlations between lean mass
and BMC/BMD, but no reduced bone mass [65],
whereas our results clearly indicate that BMC decisively
developed a deficiency in relation to LBM. Discussion Here, a corre
leptin was also found (Table 9), which may b
dynamic component of glucose regulation [6
leptin and glucose correlated significantly wit
FBM, but LBM also correlated with seru
(Table 9). Long-term and sustained weight recove
necessary before significant improvements a
[7]. Findings in the literature for body mass
suggest that a BMI threshold value (16.4 k
correlate with positive effects on bone format
Appraisals on leptin and bone developmen
in premenopausal women are rare and mostl
bone turnover markers [69]. In their study o
exic inpatients, Heer et al. [70] associated a n
induced increase of IGF-I and leptin conc
(“nutritional rehabilitation”) with a possible
effect on bone formation. While there was a
between leptin and BMC also in our sample
not demonstrate a strong association between
bone mineral parameters (Table 9) [71,72]. N
in accordance with a reported age-related
IGF-I, a negative correlation between IGF-I a
found (Table 9) [73]. In terms of the entire group and using
standards, our patients showed low serum
centrations. However, there is an obvious
between outcome groups with poor outcome
with the lowest IGF-I levels and vice versa. ings agree with those of Legroux-Gerot
investigated a group of 113 women 5.7 years
disorder onset [74]. Due to undernutrition, ac
resistance and decreased somatostatinergic in
this patient group must be assumed [75,76]. Discussion Table 9 Correlations (Spearman): body compo
bone and serum parameters - sample 2 (n = 3
Leptin
IGF-I
FBM
LBM
age (t2)
-0.30
-0.42**
BMI (body mass
index)
0.62**
-0.08
0.47**
FBM (fat body mass) 0.85**
-0.12
0
LBM (lean body
mass)
0.21
0.15
0
BMC (bone mineral
content)
0.35*
0.11
0.60** 0
BMD (bone mineral
density)
0.15
0.28
IGF-I
-0.04
1.00
Glucose
0.48**
-0.15
0.54**
0.35*
0
* = P < 0.05
** = P < 0.01 Table 9 Correlations (Spearman): body composition,
bone and serum parameters - sample 2 (n = 39)
Leptin
IGF-I
FBM
LBM
BMI
BMC
age (t2)
-0.30
-0.42**
BMI (body mass
index)
0.62**
-0.08
0.47**
0.52**
FBM (fat body mass) 0.85**
-0.12
0.68** 0.49**
LBM (lean body
mass)
0.21
0.15
0.47** 0.60**
BMC (bone mineral
content)
0.35*
0.11
0.60** 0.52**
BMD (bone mineral
density)
0.15
0.28
0.36*
0.73*
IGF-I
-0.04
1.00
Glucose
0.48**
-0.15
0.54**
0.35*
0.42**
* = P < 0.05
** = P < 0.01 Table 9 Correlations (Spearman): body composition,
bone and serum parameters - sample 2 (n = 39) Taken together, our results suggest a relatively direct
adaptation of leptin activity to weight gain, body compo-
sition (BMI, FBM), and subsequently to BMC changes. Serum leptin levels significantly correlated with nutri-
tional status parameters (BMI, FBM, glucose levels),
whereas IGF-I serum concentrations did not. Recovery status of anorexic patients does not only
refer to the actual body weight or resumption of
menses, especially in individuals who are on contracep-
tives. In the clinical context, we should carefully look on
psychopathological details (concerning eating disorder
specific core beliefs and possible comorbid conditions,
e.g. depressive or anxiety disorders), assessed by perso-
nal exploration and also by standardized instuments. Based on a trusting relationship between patient and
therapist, especially symptoms of social anxiety and the
current individual impact of the eating disorder itself
also should be asked for. frequent changes in eating behavior (Tables 3 and 8). Current nutritional status has a possible equivalent in
individual serum glucose levels. Here, a correlation with
leptin was also found (Table 9), which may be a possible
dynamic component of glucose regulation [66,67]. Both
leptin and glucose correlated significantly with BMI and
FBM, but LBM also correlated with serum glucose
(Table 9). Conclusions Our hypotheses concerning the association between the
general outcome of AN during childhood and adoles-
cence and bone mass accrual could be confirmed. With
a view to future trends, and also in accordance with
Wentz et al., a long-term BMD catch-up is something
to hope for [34]. Appraisals on leptin and bone development especially
in premenopausal women are rare and mostly limited to
bone turnover markers [69]. In their study on 19 anor-
exic inpatients, Heer et al. [70] associated a nutritionally
induced increase of IGF-I and leptin concentrations
(“nutritional rehabilitation”) with a possible and direct
effect on bone formation. While there was a correlation
between leptin and BMC also in our sample, we could
not demonstrate a strong association between IGF-I and
bone mineral parameters (Table 9) [71,72]. Nevertheless,
in accordance with a reported age-related decline of
IGF-I, a negative correlation between IGF-I and age was
found (Table 9) [73]. In our sample, bone mass accrual was clearly related to
weight gain and resumption of menses. This agrees with
the results of other studies on teenage onset anorexic
patients [27-29,34]. While hormone replacement did not
induce distinct positive effects on bone mineral develop-
ment, regular physical activity did it by trend [27]. There
was no direct association between athleticism and the
amount of weight restoration (BMI ≥17.5 kg/m2). Reduced BMD should not be seen as the decisive indi-
cator of deficient bone development due to AN, espe-
cially in the poor outcome group. The different grades
of recovery from AN, also dependent on the nutritional
state of the participants, primarily seem to have an
essential impact on the ratio of BMC to LBM. Thus, a
deficient imbalance in bone mass in relation to muscle
mass (which is a surrogate for muscle strength) during
AN, may be the cause of an increased bone fragility in
later life [77]. In terms of the entire group and using age-related
standards, our patients showed low serum IGF-I con-
centrations. However, there is an obvious difference
between outcome groups with poor outcome associated
with the lowest IGF-I levels and vice versa. These find-
ings agree with those of Legroux-Gerot et al., who
investigated a group of 113 women 5.7 years after eating
disorder onset [74]. Due to undernutrition, acquired GH
resistance and decreased somatostatinergic inhibition in
this patient group must be assumed [75,76]. Discussion Limitations of our study include no assessment of
bone turnover markers, the heterogenity of the group at
the time that mainly the hormones were measured, and
our comparatively small sample size. Subgroups should
have had additional explanatory power to provide a
more differentiated look at eating disorder outcome-
associated changes in bone metabolism. We have also
not collected data on nicotine or alcohol consumption. Long-term and sustained weight recovery may be
necessary before significant improvements are observed
[7]. Findings in the literature for body mass index [68]
suggest that a BMI threshold value (16.4 kg/m2) may
correlate with positive effects on bone formation. Discussion (This obser-
vation is independent of z-scores or t-scores based on
any suitable reference population.) Excessive exercise in patients with AN may be corre-
lated with increased psychopathology. It plays an impor-
tant role in the progression of the disease by
accelerating weight loss during dietary restriction. How-
ever, and also in our sample, a moderate extent of phy-
sical activity tends to result in a protection of further
bone mineral development [59,60]. The clinical heterogeneity of our sample is reflected in
the wide variation in serum leptin levels and presumably
also their comparatively high mean values, especially in
the poor outcome group - maybe partially caused by An evaluation of long-term (negative) effects on BMD
in 87 women diagnosed with menstrual disorders during Table 8 Bone mineral density, body composition and nutritional dependent hormones according to the general
outcome - sample 2 (n = 39; Means/SD)
Good
(n = 20)
intermediate
(n = 15)
poor
(n = 4)
X2
(df = 2)
p
BMI (kg/m2)
20,16 (± 2.10)
20,26 (± 2.10)
17.34 (± 3.37)
3.97
0.14
BMD (g/cm2)
1,10 (± ,071)
1,08 (± ,059)
0.99 (± 0.02)
7.27
0.03*
BMC (kg)
2.37 (± 0.31)
2,35 (± 0,32)
1.92 (± 0.14)
7.28
0.03*
FBM (%)
26.85 (± 7.64)
22.76 (± 7.46)
19.53 (± 8.61)
3.64
0.16
LBM (kg)
38,28 (± 4,97)
39,16 (± 3,93)
35,37 (± 3,93)
3,47
0.18
Leptin (μg/l)
12,36 (± 12,44)
5,37 (± 2,63)
12.40 (± 20.48)
3.54
0.17
IGF-I (μg/l)
216,45 (± 80,63)
223,07 (± 71,09)
119.75 (± 37.77)
7.72
0.02*
* = p < 0.05 Table 8 Bone mineral density, body composition and nutritional dependent hormones according to the general
outcome - sample 2 (n = 39; Means/SD) eral density, body composition and nutritional dependent hormones according to the general
2 (n = 39; Means/SD) ble 8 Bone mineral density, body composition and nutritional dependent hormones according to
utcome - sample 2 (n = 39; Means/SD) Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Page 8 of 11 frequent changes in eating behavior (Table
Current nutritional status has a possible eq
individual serum glucose levels. References BMC Med Phys 2009, 9:3. 8. Lenora J, Norrgren K, Thorsson O, Wollmer P, Obrant KJ, Ivaska KK: Bone
turnover markers are correlated with total skeletal uptake of 99mTc-
methylene diphosphonate (99mTc-MDP). BMC Med Phys 2009, 9:3. 9. Winston AP, Alwazeer AE, Bankart MJ: Screening for osteoporosis in
anorexia nervosa: prevalence and predictors of reduced bone mineral
density. Int J Eat Disord 2008, 41:284-287. 9. Winston AP, Alwazeer AE, Bankart MJ: Screening for osteoporosis in
anorexia nervosa: prevalence and predictors of reduced bone mineral
density. Int J Eat Disord 2008, 41:284-287. y
10. Castro J, Lazaro L, Pons F, Halperin I, Toro J: Predictors of bone mineral
density reduction in adolescents with anorexia nervosa. J Am Acad Child
Adolesc Psychiatry 2000, 39:1365-1370. 10. Castro J, Lazaro L, Pons F, Halperin I, Toro J: Predictors of bone mineral
density reduction in adolescents with anorexia nervosa. J Am Acad Child
Adolesc Psychiatry 2000, 39:1365-1370. The individual healing process in anorexia nervosa
requires a certain sustainability of (behavioral and psy-
chopathological) change, and not just physical stabliza-
tion. Therefore, with a view to a sustainable impact and
validity of clinical outcomes on bone mass development,
clinicians should preferably strive for an all-out and
long-lasting stabilization in their anorexic patients and
should not merely focus on weight normalization. The
key to effective treatment of early onset anorexia ner-
vosa is the early detection of disease and an evidence-
based treatment approach aiming for recovery as an
enduring and global process involving both psychologi-
cal and physiological normalization. y
y
11. Jayasinghe Y, Grover SR, Zacharin M: Current concepts in bone and
reproductive health in adolescents with anorexia nervosa. Bjog 2008,
115:304-315. 12. Valla A, Groenning IL, Syversen U, Hoeiseth A: Anorexia nervosa: slow
regain of bone mass. Osteoporos Int 2000, 11:141-145. 13. Golden NH, Iglesias EA, Jacobson MS, Carey D, Meyer W, Schebendach J,
Hertz S, Shenker IR: Alendronate for the treatment of osteopenia in
anorexia nervosa: a randomized, double-blind, placebo-controlled trial. J
Clin Endocrinol Metab 2005, 90:3179-3185. 14. Liu SL, Lebrun CM: Effect of oral contraceptives and hormone
replacement therapy on bone mineral density in premenopausal and
perimenopausal women: a systematic review. Br J Sports Med 2006,
40:11-24. 15. Vescovi JD, Jamal SA, De Souza MJ: Strategies to reverse bone loss in
women with functional hypothalamic amenorrhea: a systematic review
of the literature. Osteoporos Int 2008, 19:465-478. 16. Conclusions The interactions between the nutritional status of for-
mer anorexic patients, the re-accrual of their bone mass, Page 9 of 11 Page 9 of 11 Page 9 of 11 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Page 9 of 11 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 and the serum concentration of nutritionally dependent
hormones seem to be very complex. Although the
results of a longitudinal study on 42 adolescent anorexic
females by Jagielska et al. [78] reveal an improvement in
BMC and BMD which was clearly related to the nutri-
tional status, the mechanisms underlying bone loss in
AN patients still remain unclear. Despite of the predic-
tive value of hormonal and nutritional hormones (estro-
gen, insulin-like growth factor, leptin), our detailed
knowledge about their correlations with bone mineral
development in anorexic patients still remains unsatis-
factory [79,80]. Based on this rationale, and in order to
develop a more profound understanding of these pro-
cesses and their possible influence on developing bone
microarchitecture, we should carry on measuring bone
mineral and body composition parameters parallel to
(nutritionally dependent) hormones. Further realization
is particularly supposable within the framework of inter-
disciplinary elaborated clinical studies, with an intended
impact on future therapy. Authors’ contributions All authors have contributed essential parts to the manuscript and are
entirely responsible for its scientific content. PS and DS planned the study. US, SS and PS carried out the investigation. US and PS created and edited
the drafts, SS and PS did the main part of data analysis. CMW revised the
draft critically. All authors approved the final manuscript. Competing interests
f
l Except for essay analysis (see below), none of the researchers was paid any
salary or received any financial support from any commercial source for this
research. Received: 14 October 2009 Accepted: 8 July 2010 Published: 8 July 2010 Received: 14 October 2009 Accepted: 8 July 2010 Published: 8 July 2010 References Mehler PS, MacKenzie TD: Treatment of osteopenia and osteoporosis in
anorexia nervosa: a systematic review of the literature. Int J Eat Disord
2009, 42:195-201. Acknowledgements
Th
h
k
l Acknowledgements
The authors acknowledge with gratitude the help of Dr. Werner Blum, Eli
Lilly and Company, Bad Homburg, and University Children’s Hospital Giessen,
Germany, with the measurements of IGF-I and leptin. 17. Chan JL, Mantzoros CS: Role of leptin in energy-deprivation states:
normal human physiology and clinical implications for hypothalamic
amenorrhoea and anorexia nervosa. Lancet 2005, 366:74-85. References 1. Bachrach LK: Consensus and controversy regarding osteoporosis in the
pediatric population. Endocr Pract 2007, 13:513-520. 1. Bachrach LK: Consensus and controversy regarding osteoporosis in the
pediatric population. Endocr Pract 2007, 13:513-520. p
p p
2. Seibel MJ: Bone turnover in nutrition-related disorders. Wien Med
Wochenschr 2007, 157:582-588. 2. Seibel MJ: Bone turnover in nutrition-related disorders. Wien Med
Wochenschr 2007, 157:582-588. 3. Lawson EA, Miller KK, Bredella MA, Phan C, Misra M, Meenaghan E,
Rosenblum L, Donoho D, Gupta R, Klibanski A: Hormone predictors of
abnormal bone microarchitecture in women with anorexia nervosa. Bone
2010, 46:458-463. 3. Lawson EA, Miller KK, Bredella MA, Phan C, Misra M, Meenaghan E,
Rosenblum L, Donoho D, Gupta R, Klibanski A: Hormone predictors of
abnormal bone microarchitecture in women with anorexia nervosa. Bone
2010, 46:458-463. 4. Vicente-Rodriguez G: How does exercise affect bone development during
growth? Sports Med 2006, 36:561-569. 4. Vicente-Rodriguez G: How does exercise affect bone development during
growth? Sports Med 2006, 36:561-569. g
5. Giustina A, Mazziotti G, Canalis E: Growth hormone, insulin-like growth
factors, and the skeleton. Endocr Rev 2008, 29:535-559. 5. Giustina A, Mazziotti G, Canalis E: Growth hormone, insulin-like growth
factors, and the skeleton. Endocr Rev 2008, 29:535-559. Leptin actions seem to adjust rapidly to current
changes, whereas results for IGF-I may indicate some
longer-lasting aberrance in hormonal functions due to
pathologic eating behavior. Nevertheless and propably
partly linked to the individuals amount of body fat
mass, both nutritionally dependent hormones are sug-
gested to be essential components of a preservation of
neuroendocrine control of reproductive function, also in
a subset of patients who maintain menses despite low
weight [81]. 6. Weinbrenner T, Zittermann A, Gouni-Berthold I, Stehle P, Berthold HK: Body
mass index and disease duration are predictors of disturbed bone
turnover in anorexia nervosa. A case-control study. Eur J Clin Nutr 2003,
57:1262-1267. 6. Weinbrenner T, Zittermann A, Gouni-Berthold I, Stehle P, Berthold HK: Body
mass index and disease duration are predictors of disturbed bone
turnover in anorexia nervosa. A case-control study. Eur J Clin Nutr 2003,
57:1262-1267. 7. Misra M, Klibanski A: Anorexia nervosa and osteoporosis. Rev Endocr
Metab Disord 2006, 7:91-99. 7. Misra M, Klibanski A: Anorexia nervosa and osteoporosis. Rev Endocr
Metab Disord 2006, 7:91-99. 8. Lenora J, Norrgren K, Thorsson O, Wollmer P, Obrant KJ, Ivaska KK: Bone
turnover markers are correlated with total skeletal uptake of 99mTc-
methylene diphosphonate (99mTc-MDP). 1Department of Child and Adolescent Psychiatry/Psychotherapy, University of
Ulm, Germany. 2Department of Child and Adolescent Psychiatry and
Psychotherapy, University of Würzburg, Germany. 3Clinic for Nuclear
Medicine, University of Würzburg, Germany. 4Heckscher Clinic for Child and
Adolescent Psychiatry, Munich, Germany. Author details
1D
f 18. Blum WF, Englaro P, Hanitsch S, Juul A, Hertel NT, Müller J, Skakkabsek NE,
Heiman M, Birkett M, Attnanasio AM, et al: Plasma leptin levels in healthy
children and adolescents: dependence on body mass index, body fat
mass, gender, developmental stage and testosterone. J Clin Endocriol and
Metab 1997, 82:2904-2910. 1Department of Child and Adolescent Psychiatry/Psychotherapy, University of
Ulm, Germany. 2Department of Child and Adolescent Psychiatry and
Psychotherapy, University of Würzburg, Germany. 3Clinic for Nuclear
Medicine, University of Würzburg, Germany. 4Heckscher Clinic for Child and
Adolescent Psychiatry, Munich, Germany. Page 10 of 11 19. Hebebrand J, Muller TD, Holtkamp K, Herpertz-Dahlmann B: The role of
leptin in anorexia nervosa: clinical implications. Mol Psychiatry 2007,
12:23-35. 42. Lettgen B, Neudorf U, Hosse R, Peters S, Reiners C: [Bone density in
children and adolescents with rheumatic diseases. Preliminary results of
selective measurement of trabecular and cortical bone using peripheral
computerized tomography]. Klin Padiatr 1996, 208:114-117. 20. Munzberg H: Leptin-Signaling Pathways and Leptin Resistance. Forum
Nutr 2010, 63:123-132. 43. Lettgen B: Peripheral quantitative computed tomography: reference data
and clinical experiences in chronic diseases. Schönau E: Pediatric
osteology: New developments in diagnosis and therapy 1996:123-133. 21. Leinninger GM, Jo YH, Leshan RL, Louis GW, Yang H, Barrera JG, Wilson H,
Opland DM, Faouzi MA, Gong Y, et al: Leptin acts via leptin receptor-
expressing lateral hypothalamic neurons to modulate the mesolimbic
dopamine system and suppress feeding. Cell Metab 2009, 10:89-98. gy
p
g
py
44. Zanchetta JR, Plotkin H, Alvarez Filgueira ML: Bone mass in children:
normative values for the 2-20-year-old population. Bone 1995,
16:393S-399S. 22. Trayhurn P, Bing C: Appetite and energy balance signals from adipocytes. Philos Trans R Soc Lond B Biol Sci 2006, 361:1237-1249. 45. WHO: Composite international diagnostic interview.Wittchen HU, Semler
G 1990. 23. Hamrick MW, Ferrari SL: Leptin and the sympathetic connection of fat to
bone. Osteoporos Int 2008, 19:905-912. 46. Blum W: Insulin-like growth factors and their binding proteins. Diagnostics of endocrine function in children and adolescents Ranke MB ,
21996:190-218. 24. Kontogianni MD, Dafni UG, Routsias JG, Skopouli FN: Blood leptin and
adiponectin as possible mediators of the relation between fat mass and
BMD in perimenopausal women. J Bone Miner Res 2004, 19:546-551. 47. Blum W, Breier B: Radioimmunoassays for IGFs and IGFBPs. Growth Regul
1994, 4:11-19. 25. Author details
1D
f Baker D, Roberts R, Towell T: Factors predictive of bone mineral density in
eating-disordered women: a longitudinal study. Int J Eat Disord 2000,
27:29-35. 31. Castro J, Lazaro L, Pons F, Halperin I, Toro J: Adolescent anorexia nervosa:
the catch-up effect in bone mineral density after recovery. J Am Acad
Child Adolesc Psychiatry 2001, 40:1215-1221. 56. Golden NH, Carlson JL: The pathophysiology of amenorrhea in the
adolescent. Ann N Y Acad Sci 2008, 1135:163-178. 32. Wiksten-Almstromer M, Hirschberg AL, Hagenfeldt K: Reduced bone
mineral density in adult women diagnosed with menstrual disorders
during adolescence. Acta Obstet Gynecol Scand 2009, 88:543-549. 57. Golden NH, Lanzkowsky L, Schebendach J, Palestro CJ, Jacobson MS,
Shenker IR: The effect of estrogen-progestin treatment on bone mineral
density in anorexia nervosa. J Pediatr Adolesc Gynecol 2002, 15:135-143. g
y
,
33. Hartman D, Crisp A, Rooney B, Rackow C, Atkinson R, Patel S: Bone density 33. Hartman D, Crisp A, Rooney B, Rackow C, Atkinson R, Patel S: Bone density
of women who have recovered from anorexia nervosa. Int J Eat Disord
2000, 28:107-112. 58. Sim LA, McGovern L, Elamin MB, Swiglo BA, Erwin PJ, Montori VM: Effect
on bone health of estrogen preparations in premenopausal women
with anorexia nervosa: A systematic review and meta-analyses. Int J Eat
Disord 2009, 43(3):218-25. 34. Wentz E, Mellstrom D, Gillberg IC, Gillberg C, Rastam M: Brief report:
Decreased bone mineral density as a long-term complication of
teenage-onset anorexia nervosa. Eur Eat Disord Rev 2007, 15:290-295. 59. Bratland-Sanda S, Sundgot-Borgen J, Ro O, Rosenvinge JH, Hoffart A,
Martinsen EW: Physical activity and exercise dependence during
inpatient treatment of longstanding eating disorders: An exploratory
study of excessive and non-excessive exercisers. Int J Eat Disord 2009,
43(3):266-73. 35. Morgan HG, Hayward AE: Clinical assessment of anorexia nervosa. The
Morgan-Russell outcome assessment schedule. Br J Psychiatry 1988,
152:367-371. 36. Ratnasuriya RH, Eisler I, Szmukler GI, Russell GF: Anorexia nervosa: outcome
and prognostic factors after 20 years. Br J Psychiatry 1991, 158:495-502. 60. Gelegen C, Pjetri E, Campbell IC, Collier DA, Oppelaar H, Kas MJ:
Chromosomal mapping of excessive physical activity in mice in
response to a restricted feeding schedule. Eur Neuropsychopharmacol
2009, 20(5):317-26. 37. Morgan HG, Russell GF: Value of family background and clinical features
as predictors of long-term outcome in anorexia nervosa: four-year
follow-up study of 41 patients. Psychol Med 1975, 5:355-371. 61. Author details
1D
f Yakar S, Canalis E, Sun H, Mejia W, Kawashima Y, Nasser P, Courtland HW,
Williams V, Bouxsein M, Rosen C, Jepsen KJ: Serum IGF-1 determines
skeletal strength by regulating subperiosteal expansion and trait
interactions. J Bone Miner Res 2009, 24:1481-1492. 48. Blum WF, Ranke MB, Kietzmann K, Gauggel E, Zeisel HJ, Bierich JR: A
specific radioimmunoassay for the growth hormone (GH) dependent
somatomedin binding protein: its use for diagnosis of GH deficiency. J
Clin Endocrinol Metab 1990, 70:1292 1298. 26. Mika C, Holtkamp K, Heer M, Gunther RW, Herpertz-Dahlmann B: A 2-year
prospective study of bone metabolism and bone mineral density in
adolescents with anorexia nervosa. J Neural Transm 2007,
114:1611-1618. 49. Blum WF, Horn N, Kratzsch J, Jorgensen JOL, Juul A, Teale D, Mohnike K,
Ranke MB: Clinical studies of IGFBP 2 by radioimmunoassay. Growth Regul
1993, 3:98-102. 50. Fichter MM, Quadflieg N: Twelve-year course and outcome of bulimia
nervosa. Psychol Med 2004, 34:1395-1406. 27. Diamanti A, Bizzarri C, Gambarara M, Calce A, Montecchi F, Cappa M,
Bianco G, Castro M: Bone mineral density in adolescent girls with early
onset of anorexia nervosa. Clin Nutr 2007, 26:329-334. 51. Fisher M: The course and outcome of eating disorders in adults and in
adolescents: a review. Adolesc Med 2003, 14:149-158. 28. Misra M, Prabhakaran R, Miller KK, Goldstein MA, Mickley D, Clauss L,
Lockhart P, Cord J, Herzog DB, Katzman DK, Klibanski A: Weight gain and
restoration of menses as predictors of bone mineral density change in
adolescent girls with anorexia nervosa-1. J Clin Endocrinol Metab 2008,
93:1231-1237. 52. Steinhausen HC: The outcome of anorexia nervosa in the 20th century. Am J Psychiatry 2002, 159:1284-1293. 53. Garcia-De Alvaro MT, Munoz-Calvo MT, Martinez G, Barrios V, Hawkins F,
Argente J: Regional skeletal bone deficit in female adolescents with
anorexia nervosa: influence of the degree of malnutrition and weight
recovery in a two year longitudinal study. J Pediatr Endocrinol Metab 2007
20:1223-1231. 29. Wentz E, Mellstrom D, Gillberg C, Sundh V, Gillberg IC, Rastam M: Bone
density 11 years after anorexia nervosa onset in a controlled study of 39
cases. Int J Eat Disord 2003, 34:314-318. 54. Misra M: Long-term skeletal effects of eating disorders with onset in
adolescence. Ann N Y Acad Sci 2008, 1135:212-218. 30. Bachrach LK, Katzman DK, Litt IF, Guido D, Marcus R: Recovery from
osteopenia in adolescent girls with anorexia nervosa. J Clin Endocrinol
Metab 1991, 72:602-606. 55. Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 Author details
1D
f DiVasta AD, Feldman HA, Quach AE, Balestrino M, Gordon CM: The effect
of bed rest on bone turnover in young women hospitalized for anorexia
nervosa: a pilot study. J Clin Endocrinol Metab 2009, 94:1650-1655. 38. APA: Diagnostic and Statistical Manual of Mental Disorders, text revision.,
4 2006. 39. Schneider P, Biko J, Schlamp D, Trott GE, Badura F, Warnke A, Reiners C:
Comparison of total and regional body composition in adolescent
patients with anorexia nervosa and pair-matched controls. Eat Weight
Disord 1998, 3:179-187. 62. Castro J, Toro J, Lazaro L, Pons F, Halperin I: Bone mineral density in male
adolescents with anorexia nervosa. J Am Acad Child Adolesc Psychiatry
2002, 41:613-618. 40. Schlamp D, Schneider P, Krahl A, Trott GE, Warnke A: [Bone density in
anorexia nervosa–with comments on prevention and therapy of
osteoporosis]. Z Kinder Jugendpsychiatr 1994, 22:183-188. 63. Schneider P, Biko J, Reiners C, Demidchik YE, Drozd VM, Capozza RF,
Cointry GR, Ferretti JL: Impact of parathyroid status and Ca and vitamin-D
supplementation on bone mass and muscle-bone relationships in 208
Belarussian children after thyroidectomy because of thyroid carcinoma. Exp Clin Endocrinol Diabetes 2004, 112:444-450. 41. Faulkner RA, Bailey DA, Drinkwater DT, Wilkinson AA, Houston CS,
McKay HA: Regional and total body bone mineral content, bone mineral
density, and total body tissue composition in children 8-16 years of age
Calcif Tissue Int 1993, 53:7-12. 64. Cure-Cure C, Capozza RF, Cointry GR, Meta M, Cure-Ramirez P, Ferretti JL:
Reference charts for the relationships between dual-energy X-ray Page 11 of 11 Schulze et al. Child and Adolescent Psychiatry and Mental Health 2010, 4:20
http://www.capmh.com/content/4/1/20 absorptiometry-assessed bone mineral content and lean mass in 3,063
healthy men and premenopausal and postmenopausal women. Osteoporos Int 2005, 16:2095-2106. 65. Wong JC, Lewindon P, Mortimer R, Shepherd R: Bone mineral density in
adolescent females with recently diagnosed anorexia nervosa. Int J Eat
Disord 2001, 29:11-16. 66. Ahima RS: Leptin and the neuroendocrinology of fasting. Front Horm Res
2000, 26:42-56. 67. Boden G, Chen X, Mozzoli M, Ryan I: Effect of fasting on serum leptin in
normal human subjects. J Clin Endocrinol Metab 1996, 81:3419-3423. 68. Hotta M, Shibasaki T, Sato K, Demura H: The importance of body weight
history in the occurrence and recovery of osteoporosis in patients with
anorexia nervosa: evaluation by dual X-ray absorptiometry and bone
metabolic markers. Eur J Endocrinol 1998, 139:276-283. 69. Author details
1D
f Misra M, Prabhakaran R, Miller KK, Goldstein MA, Mickley D, Clauss L,
Lockhart P, Cord J, Herzog DB, Katzman DK, Klibanski A: Prognostic
indicators of changes in bone density measures in adolescent girls with
anorexia nervosa-II. J Clin Endocrinol Metab 2008, 93:1292-1297. 70. Heer M, Mika C, Grzella I, Drummer C, Herpertz-Dahlmann B: Changes in
bone turnover in patients with anorexia nervosa during eleven weeks of
inpatient dietary treatment. Clin Chem 2002, 48:754-760. 71. Matejek N, Weimann E, Witzel C, Molenkamp G, Schwidergall S, Bohles H:
Hypoleptinaemia in patients with anorexia nervosa and in elite
gymnasts with anorexia athletica. Int J Sports Med 1999, 20:451-456. 72. Nakai Y, Hamagaki S, Kato S, Seino Y, Takagi R, Kurimoto F: Role of leptin in
women with eating disorders. Int J Eat Disord 1999, 26:29-35. 73. Rosen CJ, Pollak M: Circulating IGF-I: New Perspectives for a New
Century. Trends Endocrinol Metab 1999, 10:136-141. 74. Legroux-Gerot I, Vignau J, D’Herbomez M, Collier F, Marchandise X,
Duquesnoy B, Cortet B: Evaluation of bone loss and its mechanisms in
anorexia nervosa. Calcif Tissue Int 2007, 81:174-182. 75. Misra M, Miller KK, Bjornson J, Hackman A, Aggarwal A, Chung J, Ott M,
Herzog DB, Johnson ML, Klibanski A: Alterations in growth hormone
secretory dynamics in adolescent girls with anorexia nervosa and effects
on bone metabolism. J Clin Endocrinol Metab 2003, 88:5615-5623. 76. Stoving RK, Flyvbjerg A, Frystyk J, Fisker S, Hangaard J, Hansen-Nord M,
Hagen C: Low serum levels of free and total insulin-like growth factor I
(IGF-I) in patients with anorexia nervosa are not associated with
increased IGF-binding protein-3 proteolysis. J Clin Endocrinol Metab 1999,
84:1346-1350. 77. Frost HM: Growth hormone and osteoporosis: an overview of
endocrinological and pharmacological insights from the Utah paradigm
of skeletal physiology. Horm Res 2000, 1(54 Suppl):36-43. 77. Frost HM: Growth hormone and osteoporosis: an overview of
endocrinological and pharmacological insights from the Utah paradigm
of skeletal physiology. Horm Res 2000, 1(54 Suppl):36-43. 78. Jagielska G, Wolanczyk T, Komender J, Tomaszewicz-Libudzic C, Przedlacki J,
Ostrowski K: Bone mineral content and bone mineral density in
adolescent girls with anorexia nervosa–a longitudinal study. Acta
Psychiatr Scand 2001, 104:131-137. 79. Legroux-Gerot I, Vignau J, Biver E, Pigny P, Collier F, Marchandise X,
Duquesnoy B, Cortet B: Anorexia nervosa, osteoporosis and circulating
leptin: the missing link. Osteoporos Int . 80. Misra M, Klibanski A: Neuroendocrine Consequences of Anorexia Nervosa
in Adolescents. Endocr Dev 2004, 17:197-214. Author details
1D
f 81. Miller KK, Grinspoon S, Gleysteen S, Grieco KA, Ciampa J, Breu J, Herzog DB,
Klibanski A: Preservation of neuroendocrine control of reproductive
function despite severe undernutrition. J Clin Endocrinol Metab 2004,
89:4434-4438. 81. Miller KK, Grinspoon S, Gleysteen S, Grieco KA, Ciampa J, Breu J, Herzog DB,
Klibanski A: Preservation of neuroendocrine control of reproductive
function despite severe undernutrition. J Clin Endocrinol Metab 2004,
89:4434-4438. doi:10.1186/1753-2000-4-20
Cite this article as: Schulze et al.: Bone mineral density in partially
recovered early onset anorexic patients - a follow-up investigation. Child
and Adolescent Psychiatry and Mental Health 2010 4:20. Submit your next manuscript to BioMed Central
and take full advantage of:
• Convenient online submission
• Thorough peer review
• No space constraints or color figure charges
• Immediate publication on acceptance
• Inclusion in PubMed, CAS, Scopus and Google Scholar
• Research which is freely available for redistribution
Submit your manuscript at
www.biomedcentral.com/submit Submit your next manuscript to BioMed Central
and take full advantage of: Submit your next manuscript to BioMed Central
and take full advantage of:
|
https://openalex.org/W4309129745
|
https://zenodo.org/records/7317665/files/D-132.pdf
|
Russian
| null |
SAMPLES OF PROMISING BASIL VARIETIES WITH GREEN LEAVES IN THE SOUTH OF UZBEKISTAN
|
Zenodo (CERN European Organization for Nuclear Research)
| 2,022
|
cc-by
| 2,139
|
Калит сўзлар: райҳон, яшил баргли, кўк масса ҳосилдорлиги, барг ҳосилдорлиги,
қуруқ масса ҳосилдорлиги. Калит сўзлар: райҳон, яшил баргли, кўк масса ҳосилдорлиги, барг ҳосилдорлиги,
қуруқ масса ҳосилдорлиги. SAMPLES OF PROMISING BASIL VARIETIES WITH GREEN LEAVES IN THE
SOUTH OF UZBEKISTAN Abstract. The article presents the results of the assessment of 9 varieties of basil in terms
of leaf yield, green and dry masses. High harvest leaves, green and dry masses marked in
samples Vostochny Bazaar (mixture), Basil fragrance lemon. The yield of the leaves of these
samples is 3.8-4.0 kg / m 2, which is 131.0-137.9% in relation to the standard. These same
samples are distinguished by high yields of green (leaves, stems, shoots) and dry masses. Highlighted variety samples are a valuable source material for selection. They can be
recommended for cultivation in personal plots, vegetable farms. Keywords: basil, green color, green mass yield, leaf yield, dry yield
masses. SCIENCE AND INNOVATION
INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 1 ISSUE 7
UIF-2022: 8.2 | ISSN: 2181-3337
УЎТ. 631.52+812.772
ЎЗБЕКИСТОН ЖАНУБИДА ЯШИЛ БАРГЛИ ИСТИҚБОЛЛИ РАЙҲОН НАВ
НАМУНАЛАРИ
М.Х. Арамов
қ.х.ф.д, профессор, Термиз агротехнологиялар ва инновацион ривожланиш институти
Мева-сабзавотчилик, узумчилик, иссиқхона хўжалиги кафедраси мудири
Ф.А.Нурмаматов
Сабзавот, полиз экинлари ва картошкачилик илмий-тадқиқот институти таянч докторанти
Н.А.Музафарова
Термиз агротехнологиялар ва инновацион ривожланиш институти талабаси
https://doi.org/10.5281/zenodo.7317665
Аннотация. Мақолада 9 та яшил рангли райҳон нав намуналарини кўк масса
ҳосилдорлиги, поя-новда ҳосилдорлиги ва қуритилгандаги ҳосилдорлиги бўйича баҳолаш
натижалари келтирилган. Энг юқори барг ҳосилдорлиги Восточный базар (смесь),
Базилик аромат лимона навларида кузатилган ва у 3,8-4,0 кг/м2 ни ташкил этган ва бу
стандарт Бахт навига нисбатан 131,0-137,9% ни ташкил этган. Кўк масса (барг, поя,
новда) ва қуритилгандаги ҳосилдорлиги ҳам айнан шу навларда юқори бўлган. Энг
истиқболли нав намуналари бошланғич манба сифатида селекция ишлари учун ва
томорқаларда, сабзавотчилик хўжаликларида етиштириш учун тавсия этилган.
Калит сўзлар: райҳон, яшил баргли, кўк масса ҳосилдорлиги, барг ҳосилдорлиги,
қуруқ масса ҳосилдорлиги.
SAMPLES OF PROMISING BASIL VARIETIES WITH GREEN LEAVES IN THE
SOUTH OF UZBEKISTAN
Abstract. The article presents the results of the assessment of 9 varieties of basil in terms
of leaf yield, green and dry masses. High harvest leaves, green and dry masses marked in
samples Vostochny Bazaar (mixture), Basil fragrance lemon. The yield of the leaves of these
samples is 3.8-4.0 kg / m 2, which is 131.0-137.9% in relation to the standard. These same
samples are distinguished by high yields of green (leaves, stems, shoots) and dry masses.
Highlighted variety samples are a valuable source material for selection. They can be
recommended for cultivation in personal plots, vegetable farms.
Keywords: basil, green color, green mass yield, leaf yield, dry yield Аннотация. Мақолада 9 та яшил рангли райҳон нав намуналарини кўк масса
ҳосилдорлиги, поя-новда ҳосилдорлиги ва қуритилгандаги ҳосилдорлиги бўйича баҳолаш
натижалари келтирилган. Энг юқори барг ҳосилдорлиги Восточный базар (смесь),
Базилик аромат лимона навларида кузатилган ва у 3,8-4,0 кг/м2 ни ташкил этган ва бу
стандарт Бахт навига нисбатан 131,0-137,9% ни ташкил этган. Кўк масса (барг, поя,
новда) ва қуритилгандаги ҳосилдорлиги ҳам айнан шу навларда юқори бўлган. Энг
истиқболли нав намуналари бошланғич манба сифатида селекция ишлари учун ва
томорқаларда, сабзавотчилик хўжаликларида етиштириш учун тавсия этилган. SCIENCE AND INNOVATION
INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 1 ISSUE 7
UIF-2022: 8.2 | ISSN: 2181-3337 Ҳозирги кунда сабзавот экинларининг мавжуд ассортиментини янги навларни
яратиш, янги ва кам тарқалган экинларни интродукция қилиш орқали кўпайтиришга
эришиш мумкин. Қимматли сабзавот экинларидан бири райҳон нафақат манзаралилиги, балки
дориворлиги ва таркибининг инсон учун керакли витаминлар, минерал моддаларга
бойлиги билан ҳам диққатга сазовордир. Мамлакатимизнинг турли минтақаларида
райҳонннинг жуда кўплаб маҳаллий навлари экиб етиштирилади, истеъмол қилинади. Аммо, Ўзбекистон худудида экиш учун тавсия этилган қишлоқ хўжалиги экинлари Давлат
реестрига чет элларда яратилган: Долли, Рози, Эмелли (Голландия), Фиолетовый (Россия
Федерацияси)
каби
навлар
киритилган
(Давлат
реестри,
2021). Шу
пайтгача
мамлакатимизда райҳоннинг селекцияси, уруғчилиги ва етиштириш техно- логияси
бўйича тадқиқот ишлари олиб борилмаган. Шундан келиб чиқиб СПЭ ва КИТИ
Сурхондарѐ илмий тажриба станциясида 2020-2021 йиллар давомида яшил рангли
райҳоннинг турли минтақалардан келтирилган 9 та нав намуналарини хўжалик муҳим
белгилари бўйича ўрганиш ва селекция ишлари учун бошланғич манба яратишни ўз
олдимизга мақсад қилиб қўйдик. Ушбу мақолада яшил баргли райҳон нав намуналарининг
кўк ва қуруқ масса ҳосилдорлиги бўйича маълумотлар келтирилди. Тадқиқотлар услуби. Тажрибалар Беларусь давлат қишлоқ хўжалиги академияси
илмий ходимлари Т.В.Сачивко, В.Н.Босак ва бошқалар (4) томонидан ишлаб чиқилган
“Особенности агротехники и селекции базилика (Ocimum L.)” деб номланган услубий
қўлланма асосида (БГСХА:Горки -2015) олиб борилди. Уруғлар 28 февараль плѐнка остига кўчат етиштириш учун чиринди (50%), дала
тупроғи (40%) ва қипиқ ва майдаланган сомон (10%) дан таркиб топган аралашма
тайѐрланди. Бу аралашмани 88, 1010 сх ўлчамдаги кассеталарга солинди ва суғорилиб
тувакчаларнинг ҳар бирига 2-3 та донадан уруғлар сепилиб 0,2 – 0,3 см чуқурликда
аралашма солинди, экилди ва аксарият навларнинг 10% 7 кунда, 75% ниҳоллар 12 кунда
униб чиқди суғориш ва ўғитлаш ишлари олиб борилди. Кўчатни парваришлашда хафтада 1-2 марта мунтазам суғорилади. Ўсув давомида
икки марта қўшимча озиқлантириди: 10-20 кун ўтгач; иккинчиси – биринчисидан 10-15
кундан кейин ўтказилади. Ҳавонинг энг мақбул нисбий намлиги райҳон учун – 60-70%
Кўчат сифатили Экишга тайѐр кўчат соғлом, яхши чиниқтирилган, катталиги бир хил,
пояси тўғри, сўлимаган бўлиши керак. Райҳон кўчатнинг катталиги: илидиз бўғимидан то
барглар охиригача 20-25 см (камида 15 см) барглар сони 5-7 та бўлиши керак. Поянинг
йўғонлги райҳонда 4-5 мм. Механик хусусияти қайишқоқ, кўчат таркибида намлик 87-
92% бўлади. Кўчатлар 6 апрелда очиқ далага кўчириб ўтқазилди.Тажриба қайтариқсиз олиб
борилди. Ҳисоб бўлмачаси майдони 3,5 м2. Бўлмачада ўсимликлар сони 20 та. Экиш
схемаси 70х25 см. Стандарт сифатида яшил баргли Бахт нави олинди ва у ҳар 10 та навдан
кейин жойлаштирилди. Вегетация даврида фенологик кузатувлар, ўсимликларни
морфобиологик тавсифлаш, ҳосилдорликни аниқлаш каби ишлар амалга оширилди. Ҳосилдорликни аниқлаш иккита мақсадни кўзлаб амалга оширилди. ОБРАЗЦЫ ПЕРСПЕКТИВНЫХ СОРТОВ БАЗИЛИКА С ЗЕЛЕНЫМИ ЛИСТЬЯМИ
НА ЮГЕ УЗБЕКИСТАНА Аннотация. В статье приведены результаты оценки 9 сортообразцов базилика по
урожайности листьев, зеленой и сухой массы. Высокий урожай листьев, зеленой и сухой
массы отмечен у сортообразцов Восточный базар (смесь), Базилик аромат лимона. Урожайность листьев указанных образцов составляет 3,8-4,0 кг/м 2 , что составляет
131,0-137,9% по отношению к стандарту. Эти же образцы выделяются высокой
урожайностью зеленой (листьев, стеблей, побегов) и сухой массы. Выделивщиеся
сортообразцы являются ценным исходным материалом для селекции. Их можно
рекомендовать для выращивания на приусадебных участках, овощеводческих хозяйтвах. Ключевые
слова:
базилик
зеленая
окраска
урожайность
зеленой
массы Ключевые слова: базилик, зеленая окраска, урожайность зеленой массы,
урожайность листьев, урожайность сухой массы. Ключевые слова: базилик, зеленая окраска, урожайность зеленой массы,
урожайность листьев, урожайность сухой массы. 711 SCIENCE AND INNOVATION
INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 1 ISSUE 7
UIF-2022: 8.2 | ISSN: 2181-3337 Биринчи мақсадда,
яъни райҳонни янгилигида истеъмол қилиш учун ҳосилдорликни аниқлаш ўсимликларда
гул ғунчаларнинг пайдо бўлишининг бошланишида амалга оширилди. 712 Умуман олганда поя-новдалар массаси кўк массанинг 37,7-46,2% ни ташкил этди.
Энг юқори поя ва новдалар массаси Цитрусовый фреш, Овощной лайм, Фейерверк вкуса
(смесь), Яшил баргли сада райҳон, Базилик зеленый нав намуналарида кузатилди ва кўк SCIENCE AND INNOVATION
INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 1 ISSUE 7
UIF-2022: 8.2 | ISSN: 2181-3337 Иккинчи мақсадда, яъни райҳон баргларини қуритиб ҳосилдорликни аниқлаш
ўсимликлар гуллай бошлаш фазасида амалга оширилди. Айнан шу даврда райҳон
баргларида ва гулшодасида эфир мойлари энг кўп тўпланган бўлади (5). Бунда йиғиб
олинган кўк масса уй шароитида қуритилгандан сўнг ўлчаниб ҳосилдорлик аниқланди. Вегетация даврида 5 марта ўрим ўтказилди. Ўсимликларни илдиз бўғзидан 10 см юқори
қисмидан ўриб олинди. Тадқиқот натижалари. Райҳон нав намуналари кўк масса ҳосилдорлиги
аниқланаѐтганда барг ҳосилдорлиги ва поя-новда массаси алоҳида-алоҳида аниқланади. Поя ва новдалар массаси кам бўлган нав намуналари истиқболли бўлиб ҳисобланади. Чунки озиқ-овқат мақсадида асосан райҳоннинг барглари истеъмол қилинади (1, 2, 3). Ўрганилган яшил баргли райҳон нав намуналаридан фақатгина Восточный базар (смесь),
Базилик аромат лимона навларида барглар ҳосилдорлиги 3,8-4,0 кг/м2 ни ташкил этди ва
бу стандарт навга нисбатан 31,0-37,9 % кўп демакдир, 1-жадвал. Стандарт Бахт навига
яқин ҳосилдорлик Азим навида кузатилди ва у 2,8 кг/м2 ни ташкил этди ѐки стандартга
нисбатан 96,5 % ни ташкил этди. Бошқа ўрганилган нав намуналарида барг ҳосилдорлиги
стандартга нисбатан паст бўлди ва 1,4 (Базилик зеленый) – 2,5 (Фейерверк вкуса) кг/м2 ни
ташкил этди. 1-жадвал
ил рангли райҳон нав намуналарининг кўк масса ҳосилдорлиги (кг/м2), 2020-2021
й.й. 1-жадвал
Яшил рангли райҳон нав намуналарининг кўк масса ҳосилдорлиги (кг/м2), 2020-2021
й.й. Т/р
Нав намуналари
Барг
ҳосил –
дорлиг
и, кг/м2
Стандартга
нисбатан,%
Поя ва
новдалар
массаси,
кг/м2
Кўк масса
ҳосилдор-
лиги,
кг/м2
Назоратга
нисбатан,%
1
Бахт, стандарт
2,9
100
1,8
4,7
100
2
Азим
2,8
96,5
1,7
4,5
95,7
3
Цитрусовый фреш
2,4
82,7
1,8
4,2
89,3
4
Овощной лайм
2,2
75,8
1,5
3,7
78,7
5
Базилик зеленый
1,4
48,2
1,2
2,6
55,3
6
Фейерверк вкуса
(смесь)
2,5
86,2
1,6
4,1
87,2
7
Восточный базар
(смесь)
3,8
131,0
2,3
6,1
129,7
8
Базилик аромат
лимона
4,0
137,9
2,5
6,5
138,2
9
Яшил баргли сада
райҳон
1,7
58,6
1,2
2,9
62,6
∑
23,7
15,6
39,3
2,63
1,73
4,36
У
ў
37 7 46 2% 713 SCIENCE AND INNOVATION
INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 1 ISSUE 7
UIF-2022: 8.2 | ISSN: 2181-3337 массанинг 64,0-75,0 % ни ташкил этди. Бундай навлар селекция ишларида истиқболли
бошланғич манба бўла олмайди. массанинг 64,0-75,0 % ни ташкил этди. Бундай навлар селекция ишларида истиқболли
бошланғич манба бўла олмайди. SCIENCE AND INNOVATION
INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 1 ISSUE 7
UIF-2022: 8.2 | ISSN: 2181-3337 райҳон
∑
41,1
6,1
4,56
0,67 Қуритилган масса ҳосилдорлиги бўйича эса Бахт, Азим, Восточный базар (смесь),
Базилик аромат лимона, Вейерверк вкуса (смесь) каби нав намуналари ажратилди. Ажратилган нав намуналари Ўзбекистонда райҳон селекцияси учун қимматли бошланғич
манба бўлиб ҳисобланади. массанинг 64,0-75,0 % ни ташкил этди. Бундай навлар селекция ишларида истиқболли
бошланғич манба бўла олмайди. Барг ҳосилдорлиги энг юқори бўлган Восточный базар (смесь), Базилик аромат
лимона навларида поя ва новда массаси барг ҳосилига нисбатан 60,5-62,5% ни ташкил
этди. Кўк масса ҳосилдорлиги бўйича ҳам энг юқори кўрсатгич Восточный базар
(смесь), Базилик аромат лимона навларида кузатилди ва у 6,8-6,5 кг/м2 ни ташкил этди. Бу
стандарт навга нисбатан 29,7-38,2% га юқори демакдир. Райҳон нав намуналарини қуритилгандан кейин ҳам ҳосилдорлиги аниқланди. Ушбу мақсадда ўтказилган тажрибаларда энг юқори кўк масса ҳосилдорлиги Восточный
базар (смес), Базилик аромат лимона нав намуналарида кузатилди ва у 6,8-6,9 кг/м2 ни
ташкил этди. Бу стандарт нав Бахтга нисбатан 23,6-25,4% кўп демакдир. Қуритилгандан
кейинги ҳосилдорлик ҳам айнан шу навларда юқори бўлди ва 1,0-1,1 кг/м2 ни ташкил
этди. Стандарт Бахт навида ушбу кўрсатгич 0,9 кг/м2 ни ташкил этди, 2-жадвал. Қуритилган масса навга қараб кўк массанинг 5,4-19,9% ни ташкил этди. Бу кўрсатгич
бўйича энг яхши нав намуналари Бахт, Азим, Восточный базар (смесь), Базилик аромат
лимона, Вейерверк вкуса (смесь) бўлиб, буларда қуруқ масса ҳосилдорлиги 0,7-1,1 кг/м2
ни ташкил этди. Бу эса ўз навбатида кўк масса ҳосилининг 12,7-19,9% ни ташкил этади. Айнан шундай навлар селекция ишларида қимматли бошланғич материал бўлиб
ҳисобланади. Шундай қилиб ўрганилган яшил райҳон нав намуналаридан кўк масса
ҳосилдорлиги энг юқори бўлган Восточный базар (смесь), Базилик лимонный аромат нав
намуналари ажратилди. 2 жадвал
Яшил рангли райҳон нав намуналарининг қуритилгандаги ҳосилдорлиги, 2020-2021
й.й. Т/р
Нав намуналари
Кўк
масса
ҳосилдо
рлиги,
кг/м2
Қиѐсий
навга
нисба-
тан,%
Қуритил-
ган масса
ҳосилдор-
лиги,
кг/м2
Кўк
массага
нисбатан,
%
Қиѐсий
навга
нисбатан,%
1
Бахт, стандарт
5,5
100
0,9
16,3
100
2
Азим
4,2
76,3
0,6
10,9
66,9
3
Цитрусовый фреш
3,4
61,8
0,5
9,1
55,8
4
Овощной лайм
3,2
58,2
0,5
9,2
56,4
5
Базилик зеленый
3,5
63,6
0,5
9,0
55,2
6
Фейерверк вкуса
(смесь)
4,8
87,2
0,7
12,7
77,9
7
Восточный базар
(смесь)
6,1
123,6
1,0
18,1
111,0
8
Базилик аромат
лимона
6,5
125,4
1,5
23,0
141,1
9
Яшил баргли сада
2,8
51,2
0,3
5,4
33,1 Яшил рангли райҳон нав намуналарининг қуритилгандаги ҳосилдорлиги ил рангли райҳон нав намуналарининг қуритилгандаги ҳосилдорлиги, 2020-2021
й й 714 REFERENCES 1. Лущиц Т.Е. Пряно-ароматические растения. Минск: Интерпрессервис, 2002. – 80 с. 2. Мустяцэ
Г.И. Возделывание
ароматических
растений/
Г.И.Мустяцэ. –
Кишинев:Штиинца, 1988. – 200 с. 1. Лущиц Т.Е. Пряно-ароматические растения. Минск: Интерпрессервис, 2002 1. Лущиц Т.Е. Пряно-ароматические растения. Минск: Интерпрессервис, 2002. – 80 с. 2. Мустяцэ
Г.И. Возделывание
ароматических
растений/
Г.И.Мустяцэ. –
Кишинев:Штиинца, 1988. – 200 с. 2. Мустяцэ
Г.И. Возделывание
ароматических
растений/
Г.И.Мустяцэ. –
Кишинев:Штиинца, 1988. – 200 с. 3. Пастушенков Л.В., Пастушенков А.Л., Пастушенков В.Л. Лекарственные растения:
использование в народной медицине и быту. Л.: Лениздат,1990. – 384 с. 3. Пастушенков Л.В., Пастушенков А.Л., Пастушенков В.Л. Лекарственные растения:
использование в народной медицине и быту. Л.: Лениздат,1990. – 384 с. 4. Сачивко Т.В, Босак В.Н, Коваленко Н.А, Супиченко Г.Н. Особенности
агротехники и селекции базилика Ocimum basilicum L: рекомендации. Горьки:
БГСХА-2015. - 28 с; 4. Сачивко Т.В, Босак В.Н, Коваленко Н.А, Супиченко Г.Н. Особенности
агротехники и селекции базилика Ocimum basilicum L: рекомендации. Горьки:
БГСХА-2015. - 28 с; 5. Фогель И.В. Некоторые особенности накопления эфирного масла у базилика
огородного (Ocimum basilicum L.)//Науч.-тех. бюл. ВИР,1995. – Вып. 234. – С. 78-80. 6. Ўзбекистон Республикаси худудида экиш учун тавсия этилган қишлоқ хўжалиги 5. Фогель И.В. Некоторые особенности накопления эфирного масла у базилика
огородного (Ocimum basilicum L.)//Науч.-тех. бюл. ВИР,1995. – Вып. 234. – С. 78-80. 5. Фогель И.В. Некоторые особенности накопления эфирного масла у базилика
огородного (Ocimum basilicum L.)//Науч.-тех. бюл. ВИР,1995. – Вып. 234. – С. 78-80. 6. Ўзбекистон Республикаси худудида экиш учун тавсия этилган қишлоқ хўжалиги
экинлари давлат реестри. Ташкент, 2021.-38 б. 6. Ўзбекистон Республикаси худудида экиш учун тавсия этилган қишлоқ хўжалиги
экинлари давлат реестри. Ташкент, 2021.-38 б. 715
|
https://openalex.org/W2163031497
|
https://boris.unibe.ch/87683/8/1-s2.0-S0370269314008648-main.pdf
|
English
| null |
Search for the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"><mml:msub><mml:mrow><mml:mi>X</mml:mi></mml:mrow><mml:mrow><mml:mi>b</mml:mi></mml:mrow></mml:msub></mml:math> and other hidden-beauty states in the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.gif" overflow="scroll"><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><…
|
Physics letters. B
| 2,015
|
cc-by
| 24,914
|
1. Introduction pends on the branching fraction for Xb →π+π−Υ (1S), which is
unknown. The π+π−Υ (1S) channel also provides the opportunity to
measure the production of the Υ (13D J) states. These have not
been observed at the Tevatron; their production cross sections
in pp collisions are also unknown, but an early colour-octet cal-
culation [17] gives values comparable to that of the Υ (2S). The
Υ (13D2) has been observed in radiative transitions by CLEO [18]
and BaBar [19]. The X(3872) is the first and the best-studied of the new
hidden-charm states seen in the last decade. Observed by Belle in
decays B± →K ± X(→π+π−J/ψ) [1], it was quickly confirmed
by BaBar [2], CDF [3], and DØ [4]. In particular, CDF and DØ found
that the X(3872) is produced directly in pp collisions; recently
CMS has measured the product of the pp production cross section
and the π+π−J/ψ branching fraction to be (6.56 ± 0.29 ± 0.65)%
of the value for the ψ(2S) [5]. The mass, narrow width, J PC = 1++
quantum number assignment [6–10], and decay characteristics of
the X(3872) make it unlikely to be a conventional quarkonium
state, and there is an extensive literature discussing its structure. Weakly bound D0D∗0 molecular models (for example, Refs. [11,
12]) have been popular due to the proximity of the X(3872) to
the D0D∗0 threshold; various [qc][¯q¯c] tetraquark (for example,
Refs. [13,14]) and other models have also been proposed. The production of Υ (10 860) and some other hidden-beauty
states may also be studied using π+π−Υ (1S). The Υ (10 860) de-
cay to π+π−Υ (1S) has a surprisingly large partial width [20–22]:
current world average results are (0.29 ± 0.15) MeV for the
Υ (10 860), to be compared with (0.89 ± 0.08) keV for the Υ (3S),
and (1.7 ± 0.2) keV for the Υ (4S) [23]. Belle has also presented
evidence of exotic substructure in this decay [24]. The natural
widths of the Υ (10 860), Υ (11 020), and other states above the
open-beauty threshold are larger than the detector resolution, and
must be explicitly considered in any search. Heavy-quark symmetry suggests the existence of a hidden-
beauty partner – a so-called Xb state – which should be produced
in pp collisions [15]. The molecular model of Swanson [12,16]
predicts an Xb mass of 10561 MeV, while tetraquark predictions
vary: for example, Ref. a b s t r a c t Article history:
Received 16 October 2014
Received in revised form 26 November 2014
Accepted 26 November 2014
Available online 2 December 2014
Editor: W.-D. Schlatter This Letter presents a search for a hidden-beauty counterpart of the X(3872) in the mass ranges of
10.05–10.31 GeV and 10.40–11.00 GeV, in the channel Xb →π+π−Υ (1S)(→μ+μ−), using 16.2 fb−1 of
√
s = 8 TeV pp collision data collected by the ATLAS detector at the LHC. No evidence for new narrow
states is found, and upper limits are set on the product of the Xb cross section and branching fraction,
relative to those of the Υ (2S), at the 95% confidence level using the CLS approach. These limits range
from 0.8% to 4.0%, depending on mass. For masses above 10.1 GeV, the expected upper limits from
this analysis are the most restrictive to date. Searches for production of the Υ (13D J), Υ (10 860), and
Υ (11 020) states also reveal no significant signals. © 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license
(http://creativecommons.org/licenses/by/3.0/). Funded by SCOAP3. Search for the Xb and other hidden-beauty states
in the π+π−Υ (1S) channel at ATLAS .ATLAS Collaboration ⋆ ⋆E-mail address: atlas.publications@cern.ch. .
.055
shed by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/3.0/). Funded by Physics Letters B 740 (2015) 199–217 Physics Letters B 740 (2015) 199–217 ⋆E-mail address: atlas.publications@cern.ch.
peaks are used to validate the measurement technique. Results are
http://dx.doi.org/10.1016/j.physletb.2014.11.055
0370-2693/© 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/3.0/). Funded by
SCOAP3. dx.doi.org/10.1016/j.physletb.2014.11.055
2693/© 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/3.0/). Funded by
3 1 ATLAS uses a right-handed coordinate system with its origin at the nominal in-
teraction point (IP) in the centre of the detector, the x-axis pointing to the centre
of the LHC ring, and the z-axis along the beam pipe; the y-axis points upward.
Cylindrical coordinates (r, φ) are used in the transverse plane; φ is the azimuthal
angle around the beam pipe. Pseudorapidity and transverse momentum are de-
fined in terms of the polar angle θ as η = − ln(tanθ/2) and pT = p sinθ. The
(η, φ) distance between two particles is defined as R =
( η)2 + ( φ)2. For a
particle with momentum ⃗p = (px, p y, pz) and energy E, the rapidity is defined as
y = 0.5 ln([E + pz]/[E −pz]). 2. The ATLAS detector In the remainder of the event, dipion candidates are formed
from oppositely charged pions with |ηπ| < 2.5, each required to
have ≥1 pixel hits, ≥6 silicon microstrip hits, and pπ
T > 400 MeV;
no other requirements (such as lepton vetoes) are imposed. The
Υ (1S) candidate and the dipion system are combined by perform-
ing a four-track common-vertex fit, with the μ+μ−mass con-
strained to m1S, and tracks assigned μ or π masses as appropri-
ate. This significantly improves the mass resolution: for example,
in the Υ (2S) simulation, the RMS improves from 142 MeV to
9.7 MeV. The π+π−Υ (1S) vertex fit is required to have a chi-
square less than 20; this is 95% efficient for Υ (2S) decays but
reduces background by a factor of ∼10. All remaining π+π−Υ (1S)
candidates with invariant masses up to 11.2 GeV are retained. The ATLAS detector [26] is composed of an inner tracking sys-
tem, calorimeters, and a muon spectrometer. The inner detector
(ID) surrounds the pp interaction point and consists of silicon pixel
and microstrip detectors, and a transition radiation tracker, all im-
mersed in a 2 T axial magnetic field. The ID spans the pseudora-
pidity1 range |η| < 2.5 and is enclosed by a system of electromag-
netic and hadronic calorimeters. Surrounding the calorimeters is
the muon spectrometer (MS) consisting of three large air-core su-
perconducting magnets (each with eight coils) providing a toroidal
field, a system of precision tracking chambers, and fast detectors
for triggering. Monitored drift tubes and cathode-strip chambers
provide precision measurements in the bending plane of muons
within the pseudorapidity range |η| < 2.7. Resistive plate and thin
gap chambers are used to make fast event data-recording decisions
in the ranges |η| < 1.05 and 1.05 < |η| < 2.4 respectively, and also
provide position measurements in the non-bending plane and im-
prove pattern recognition and track reconstruction. MS momentum
measurements are based on track segments formed in at least two
of the three precision chamber planes. For a state decaying to π+π−Υ (1S), the acceptance A is de-
fined as the fraction of decays where both muons have pμ
T >
4 GeV, both pions have pπ
T > 400 MeV, and all four particles are
within |η| < 2.5. 2 An un-prescaled trigger with a pμ
T = 6 GeV threshold on the muons was also
considered, but found to result in a lower sensitivity using the optimisation proce-
dure described in Section 5. 1. Introduction [14] predicts masses of 10 492, 10 593, or
10 682 MeV, depending on the flavour of the light quarks. In 2013, CMS reported [25] the results of their search for Xb →
π+π−Υ (1S)(→μ+μ−), finding no evidence for narrow states in
the 10.06–10.31 GeV and 10.40–10.99 GeV mass ranges. They set
upper limits on the product of cross section and branching fraction
at values between 0.9% and 5.4% of the Υ (2S) rate. The decay Xb →π+π−Υ (1S)(→μ+μ−), analogous to the
decay mode in which the X(3872) was discovered, provides a
straightforward way to reconstruct an Xb. Any resulting measure-
ment or upper limit on the Xb production cross section then de- This Letter presents a search for the Xb and other hidden-
beauty states at ATLAS, using a 16.2 fb−1 pp collision data sam-
ple collected at √
s = 8 TeV during the 2012 run of the LHC. The analysis is performed simultaneously across eight kinematic
bins of varying sensitivity; the Υ (2S) and Υ (3S) →π+π−Υ (1S)
peaks are used to validate the measurement technique. Results are ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 200 presented in terms of the product of production cross section and
π+π−Υ (1S) branching fraction, relative to that for the Υ (2S). 350 MeV of the Υ (1S) mass [23], m1S, is retained and consid-
ered an Υ (1S) →μ+μ−candidate. To confirm that this pair is
the same as that used in the trigger, the reconstructed and trigger-
level muons are required to match with R < 0.01. 2. The ATLAS detector States with pT < 5 GeV or rapidity |y| > 2.4 have
very low acceptance, so candidates in these regions (which also
suffer from high background) are excluded. 4. Data and simulation samples The ATLAS detector employs a three-level trigger [27] to re-
duce the 20 MHz proton bunch collision rate to the few-hundred
hertz transfer rate to mass storage. This analysis is based on a
Level-1 muon trigger that searches for hit coincidences between
muon trigger detector layers inside pre-programmed geometrical
windows that bound the path of muon candidates above a given
pμ
T
threshold, and provide a rough estimate of their position,
for |ημ| < 2.4. There are two subsequent software-based trigger
stages, in which muon candidates incorporate, with increasing pre-
cision, information from both the MS and the ID, reaching position
and momentum resolution close to that provided by the offline re-
construction. The techniques adopted in this analysis were developed us-
ing √
s = 7 TeV data collected in 2011 and simulation samples
generated under the same running conditions, with particular at-
tention to Υ (2S) →π+π−Υ (1S) mass and (|y|, pT) distributions. Backgrounds due to inclusive Υ (1S) production and combinato-
rial μ+μ−sources were studied using μ+μ−sideband and μ±μ±
same-sign samples, and found to be featureless above 9.8 GeV. The results presented here are based on data from the 2012
√
s = 8 TeV pp run at the LHC; standard data-quality criteria are
used to ensure efficient detector performance. The trigger em-
ployed in the event selection was subject to an instantaneous
luminosity-dependent prescale factor,2 and provided an integrated
luminosity of L = 16.2 fb−1. The resulting data sample includes
over 10 million μ+μ−combinations: a fit to the sample finds
(6.00 ± 0.01) × 106 from Υ (1S) decays, (0.200 ± 0.002) × 106
from Υ (2S) decays, and the remainder from combinatorial back-
ground. Given the reconstruction and event selection choices de-
scribed in the previous section, each dimuon gives rise (on aver-
age) to 19.5 π+π−Υ (1S) candidates with invariant mass below
11.2 GeV. A procedure to select at most one candidate per event
was considered. However, after the adoption of the binning ap-
proach described in Section 5, candidate selection was found to
worsen the expected sensitivity to a hypothetical Xb signal. There-
fore, all π+π−Υ (1S) candidates are retained for analysis. 3. Reconstruction and event selection Events are selected using a trigger requiring two muons of
opposite charge, each with pμ
T > 4 GeV, successfully fitted to a
common vertex. The μ+μ−mass range accepted by the trigger,
8–12 GeV, includes the Υ (1S), Υ (2S), and Υ (3S) signal peaks. In the offline reconstruction for this analysis, muon reconstruc-
tion relies on a statistical combination of an MS track and an ID
track. The selected muons are restricted to |ημ| < 2.3, ensuring
high-quality tracking and a reduction of fake muon candidates. This restriction also removes regions of strongly varying efficiency
and acceptance. The reconstruction of π+π−Υ (1S) candidates begins with pairs
of oppositely charged muon candidates that satisfy the same kine-
matic conditions used by the trigger, and have ≥2 pixel and ≥6
silicon microstrip detector hits. Each pair is subjected to a common
vertex fit, and a loose chi-square selection is imposed to exclude
very poor candidates. Any dimuon with an invariant mass within Simulated samples are used to optimise the selections, model
signal decays, develop fitting models, and calculate efficiencies. In-
dividual samples are used for the Υ (2S), Υ (3S), Υ (13D J) triplet,
Υ (10 860), and for two hypothetical Xb masses, 10 233 MeV and
10 561 MeV. Production is modelled with the AU2 [28] tune of
Pythia 8.170 [29] and the CTEQ6L1 [30] parton distribution func-
tions. In the decay to π+π−Υ (1S), the three-body phase space is
uniformly sampled. Isotropic spin alignment of the parent is as-
sumed: for Υ (2S) and Υ (3S) this is supported by a recent CMS
measurement [31]. Passage of particles through the detector is ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 201 Fig. 1. The π+π−Υ (1S) invariant mass distribution in the kinematic bin most sen-
sitive to an Xb signal: |y| < 1.2, pT > 20 GeV, and cosθ∗> 0. The only apparent
peaks are at the masses of the Υ (2S) (10023 MeV) and Υ (3S) (10355 MeV). simulated with Atlfast II [32], supplementing Geant4 [33,34] with
a parameterised calorimeter response. Simulated kinematic distributions of the final-state pions and
muons are sensitive to mismodelling of the pT and y distributions
of the parent state. 5. Fitting strategy Due to the low pion momentum in the π+π−Υ (1S) rest frame,
and the reconstruction threshold of pπ
T = 400 MeV in the labo-
ratory frame, true π+π−Υ (1S) decays are preferentially recon-
structed if the parent has large pT or small θ∗(defined as the
angle, in the parent rest frame, between the dipion momentum
and the lab-frame parent momentum). In background candidates,
the dipion and dimuon systems are unrelated, and the dipions
typically have low pππ
T
in the lab; boosting to the π+π−μ+μ−
frame yields large values of θ∗, with a broad distribution around
cosθ∗= 0. In the (pT, cosθ∗) plane, then, the ratio of signal to
background candidates is largest in the upper-right region, and
smallest in the lower-left. y
pT
cos θ
The shape of the signal peaks reflects the detector resolution,
which differs between the barrel and endcap, and varies as a func-
tion of mass; in a given rapidity bin at a given mass, a single
function can be used across the whole (pT, cosθ∗) range. In each
rapidity bin, the signal is fitted using two Gaussians with a com-
mon mean, a narrow component fraction f , and a ratio r of broad
to narrow widths. These parameters are found to be independent
of mass, and are fixed to the average values across the simula-
tion samples. The remaining parameter, the width of the narrow
component, σ , depends linearly on the mass of the parent state. Together with the splitting functions defined above, this allows the
signal shape and the fraction of the signal falling in each of the
analysis bins to be determined for any Xb mass. The mass resolution and background shape differ at central and
forward rapidities, so the analysis is performed in bins of |y| < 1.2
(barrel) and 1.2 < |y| < 2.4 (endcap). Several possible ways to ex-
ploit the (pT, cosθ∗) discrimination were considered, including fur-
ther binning, a diagonal cut in (pT, cosθ∗), and a requirement on
the R between the Υ (1S) and each pion (as used by CMS [25]). The choice of method was based on optimising the expected sig-
nificance for a weak signal at a mass of 10 561 MeV. In the final
approach eight analysis bins of varying sensitivity are used, formed
from combinations of high and low |y|, high and low pT, and high
and low cosθ∗. 3. Reconstruction and event selection ATLAS has measured doubly differential pro-
duction cross sections for Υ (2S) and Υ (3S) at 7 TeV in pT bins
up to 70 GeV for |y| < 1.2 and 1.2 < |y| < 2.25 [35]. These results
can be extended to |y| < 2.4 assuming flat rapidity dependence,
and up to pT = 100 GeV using CMS measurements [36]. The result-
ing Υ (2S) cross section is compared to the production kinematics
of a 7 TeV simulation using the 2011 ATLAS tune [37] of Pythia
6.4 [38]. The ratio of the two in (|y|, pT) bins defines production
weights, which are applied to the 8 TeV Υ (2S) simulated sample,
assuming that Pythia correctly models the increase in cross sec-
tion with √
s. The same procedure is used for the Υ (3S); for other
masses, linear extrapolation of the Υ (2S) and Υ (3S) weights is
used. The simulated Υ (2S) and Υ (3S) →π+π−Υ (1S) samples are
further reweighted to match dipion mass distributions observed by
CLEO [39,40], to allow comparison of simulation and data. Fig. 1. The π+π−Υ (1S) invariant mass distribution in the kinematic bin most sen-
sitive to an Xb signal: |y| < 1.2, pT > 20 GeV, and cosθ∗> 0. The only apparent
peaks are at the masses of the Υ (2S) (10023 MeV) and Υ (3S) (10355 MeV). as splitting functions. At any specified mass, the signal yield frac-
tion in any particular (|y|, pT, cosθ∗) bin can be calculated from an
appropriately chosen product of three of these and their comple-
ments, (1 −S). For example, the fraction in the bin (|y| < 1.2, pT >
20 GeV, cosθ∗< 0) is given by S|y| · (1 −Sb
pT(m)) · S(3)
cos θ∗(m). 5. Fitting strategy The optimal bin boundaries for pT and cosθ∗were
determined to be 20 GeV and 0, respectively. Searches for the production of the Υ (10 860) and Υ (11 020),
which have natural widths larger than the experimental resolu-
tion, are also performed. Each of these states is modelled as a
Breit–Wigner convolved with the mass-dependent signal shape de-
scribed in the previous paragraph, representing the detector reso-
lution. The fractions of the Υ (10 860) signal falling in the eight
analysis bins are extracted from the simulation, while those for
the Υ (11 020) are determined by extrapolation. All fits presented here are binned, extended maximum-likeli-
hood fits in a local region around the mass of interest. The bin
width is 2 MeV in all fits. The background is described by a lin-
ear combination of Chebychev polynomials up to second-order,
with independent parameters in each analysis bin, unless other-
wise specified. The π+π−Υ (1S) mass distribution for the most sensitive bin
(|y| < 1.2, pT > 20 GeV, cosθ∗> 0) is shown in Fig. 1. The Υ (2S)
and Υ (3S) peaks are clearly visible, but no other peaks are ap-
parent. The background in this bin decreases with mass above the
Υ (3S), whereas the fraction of signal events falling in this bin is
constant above the Υ (3S) in the simulation. Thus higher sensitivity
is expected at larger masses. 6. Results for the Υ (2S) and Υ (3S) To test kine-
matic distributions in the Υ (2S) simulation, signal fractions in the
eight analysis bins are checked against their expected values, and
are found to be consistent within statistical uncertainties. where the product of the cross section and branching fraction,
(σB)2S, is estimated from the extended cross-section measure-
ment (see Section 4) using world-average values for the branching
fractions B(Υ (1S) →μ+μ−) and B(Υ (2S) →π+π−Υ (1S)) [23]. The shape of the doubly differential cross section is also used
to calculate the acceptance, A = (1.442 ± 0.004)%, assuming the
CLEO dipion mass spectrum [39] and isotropic signal decays. The
reconstruction efficiency for decays within the acceptance, ϵ =
0.283 ± 0.002, is taken from the Υ (2S) simulation. To test kine-
matic distributions in the Υ (2S) simulation, signal fractions in the
eight analysis bins are checked against their expected values, and
are found to be consistent within statistical uncertainties. At each mass, the p-value is extracted using the asymptotic
formula [41] for the q0 statistic, a modification of the standard
likelihood ratio (see Fig. 3). No evidence for new states with local
significance z ≥3 is found. The expected number of Xb events can be written as N = N2S · R · A
A2S
· ϵ
ϵ2S
,
(2) N = N2S · R · A
A2S
· ϵ
ϵ2S
, N = N2S · R · A
A2S
· ϵ
ϵ2S
, (2) where R ≡(σB)/(σB)2S, the production rate relative to that of
the Υ (2S). The efficiency, ϵ, as a function of mass is determined
by fitting a function a + b/(1 + e−c(m−d)) to the values from the
simulated samples. The acceptance increases with the mass of the
parent state due to the increased energy available to the pions
and muons. Additionally, the measured production spectra of the
Υ (1S), Υ (2S), and Υ (3S) states [35] are progressively harder in
pT with increasing mass. The acceptance for a hypothetical Xb
state of arbitrary mass is estimated here by linear extrapolation
of calculations performed at the Υ (2S) and Υ (3S), using the mea-
sured production spectra of these states. The ratio (Aϵ)/(Aϵ)2S
rises from 1.1 at m = 10 GeV to 7.5 at m = 11 GeV. 6. Results for the Υ (2S) and Υ (3S) Based on the simulation samples, the fraction of signal in the
barrel region |y| < 1.2 is independent of mass with an aver-
age value of S|y| = 0.606 ± 0.004. Within the barrel, the frac-
tion of signal with pT < 20 GeV develops smoothly with mass
and can be characterised by an analytic turn-on curve Sb
pT(m) =
a/(1 + e−b(m−c)). In the endcap, the dependence is described by
Sec
pT(m), which has the same functional form as Sb
pT(m) with dif-
ferent values for the parameters. Similarly, within each (|y|, pT)
bin the fraction of the signal with cosθ∗< 0 is modelled with a
quadratic function, S(i)
cos θ∗(m) = a + bm + cm2, where i = 1–4 labels
the bin. These S functions, seven in total, are referred to below Fits to the π+π−Υ (1S) spectrum near the Υ (2S) are first
performed separately in barrel and endcap bins, across the full
(pT, cosθ∗) range, with signal mass and width parameters free in
the fit (Figs. 2a and 2b). In both cases, the mass is consistent with
the world average for the Υ (2S), and the σ parameters are within
uncertainties of the values fitted to the Υ (2S) simulation. Signal shape parameters are then fixed to simulated values to
reduce uncertainties, and a separate fit is performed on each anal-
ysis bin. The fraction of signal decays falling in the barrel is mea-
sured to be 0.67 ± 0.04, compared to 0.606 ± 0.004 in the simula- ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 202 202
ATLAS Collaboration / Physics Letters B 740 (2015) 199–217
Fig. 2. The measured π+π−Υ (1S) invariant mass (data points), together with fits (red solid curves) to the Υ (2S) peak in the (a) barrel and (b) endcap, with signal mass (m)
and width parameters (σb and σec, respectively) free; and (c) a fit to the Υ (3S) peak in the most sensitive bin, with zero suppressed on the vertical scale. Ns is the fitted
signal yield in each bin. The background component (green, long-dashed) and the signal component (peaked blue curve) are also shown separately. In each case, the lower
panel shows background-subtracted data, with the total signal function (blue solid) and its two Gaussian components (pink, short-dashed curves) overlaid. 6. Results for the Υ (2S) and Υ (3S) A simultaneous fit to the analysis bins is also performed at
the Υ (3S) mass, with reduced χ 2 = 1.0 and statistical significance
(from the likelihood-ratio test statistic) z = 8.7. An individual fit
to the most sensitive bin (shown in Fig. 2(c), with larger binning
to emphasise the peak) has significance z = 6.5. The total Υ (3S)
yield, 11 600 ± 1300, agrees with the prediction estimated analo-
gously to Eq. (1), 11 400 ± 1500. 7.1. Hypothesis tests Using Eq. (2) and the formalism from Ref. [41], the expected
significance for a relative production rate R = 6.56% (the value of
the analogous quantity for the X(3872) [5]) is calculated as a func-
tion of mass, shown as the dashed blue line in Fig. 3; it exceeds 5σ
for m ≳10.12 GeV. Expectations for a weaker signal with R = 3%
are also shown (long-dashed red line). Given the null result, up-
per limits are calculated on R after modifying the fit to include
systematic uncertainties. A hypothesis test for the presence of an Xb peak is performed
every 10 MeV from 10 GeV to 11 GeV, assuming a narrow state3
that has a differential cross section with a (|y|, pT) distribution
similar to that of the Υ (2S) or Υ (3S), decaying according to three-
body phase space. The signal shape and bin splittings are treated
as described in Section 5. At each mass, a simultaneous fit to the
analysis bins is performed in a range m ± 8σec, where σec(m) is
the width of the narrow signal component in the endcap: the win-
dow varies from ±72 MeV at 10 GeV to ±224 MeV at 10.9 GeV; 3 Here, a narrow state refers to one whose natural width is much smaller than
the experimental resolution. 6. Results for the Υ (2S) and Υ (3S) (For interpretation
of the references to color in this figure legend, the reader is referred to the web version of this article.) Fig. 2. The measured π+π−Υ (1S) invariant mass (data points), together with fits (red solid curves) to the Υ (2S) peak in the (a) barrel and (b) endcap, with signal mass (m)
and width parameters (σb and σec, respectively) free; and (c) a fit to the Υ (3S) peak in the most sensitive bin, with zero suppressed on the vertical scale. Ns is the fitted
signal yield in each bin. The background component (green, long-dashed) and the signal component (peaked blue curve) are also shown separately. In each case, the lower
panel shows background-subtracted data, with the total signal function (blue solid) and its two Gaussian components (pink, short-dashed curves) overlaid. (For interpretation
of the references to color in this figure legend, the reader is referred to the web version of this article.) tion; similar results were seen in 7 TeV data. The ratio 0.67/0.606
is used to rescale the barrel fraction in the simulation. near 11 GeV, m −8σec < m < 11.2 GeV is used. When fitting
near the Υ (2S) and Υ (3S) regions, the lineshapes for these signal
components are added to the background model, with normali-
sations governed by Gaussian constraints to the values obtained
from the fits given in Section 6. In the immediate vicinity of the
peaks, m2S,3S ± 4σb, no search is performed; the width of the nar-
row signal component in the barrel, σb, is 5.66 MeV (9.37 MeV)
at the Υ (2S) (Υ (3S)) mass. This reduces the analysis range to
10.05–10.31 and 10.40–11.00 GeV. The total fitted yield N2S = 34 300 ± 800 is consistent with (1) Nexpected
2
= (σB)2S · L · A · ϵ = 33 300 ± 2500,
(1) where the product of the cross section and branching fraction,
(σB)2S, is estimated from the extended cross-section measure-
ment (see Section 4) using world-average values for the branching
fractions B(Υ (1S) →μ+μ−) and B(Υ (2S) →π+π−Υ (1S)) [23]. The shape of the doubly differential cross section is also used
to calculate the acceptance, A = (1.442 ± 0.004)%, assuming the
CLEO dipion mass spectrum [39] and isotropic signal decays. The
reconstruction efficiency for decays within the acceptance, ϵ =
0.283 ± 0.002, is taken from the Υ (2S) simulation. 7.3. Upper limit calculation Alterna-
tive extrapolations between the Υ (1S) and Υ (2S), and between
Υ (1S) and Υ (3S), are also tried; the greatest change in the accep-
tance ratio, 12%, is assigned as the uncertainty. If an Xb state exists and lies within the range of masses to
which this analysis is sensitive, its production cross section and/or
its branching fraction must be lower, relative to the Υ (2S), than
that of the X(3872) relative to the ψ(2S). There are arguments
that the decay Xb →π+π−Υ (1S) should be suppressed, in the
absence of the strong isospin-violating effects that are present for
X(3872) →π+π−J/ψ [46,47]. In this case the Xb would have
more prominent decays to π+π−χb1, π+π−π 0Υ (1S), and other
final states which are relatively difficult to reconstruct. The parameters of the efficiency, the splitting functions, and the
widths of the narrow signal components σb and σec as functions
of mass, are varied by the uncertainties on their fitted values; al-
ternative functional forms are also tried. In each case, the largest
deviation is assigned as the systematic uncertainty. The use of
production weights (described in Section 4) relies on assumptions
regarding rapidity dependence, and evolution from √
s = 7 TeV to
8 TeV. Removing these weights produces a ∼1% change in effi-
ciency ratio (most of the differences cancel), but changes the val-
ues of the splitting functions by up to 8%. All results to this point assume that any hypothetical Xb pro-
duction is unpolarised. Angular distributions of the Υ (1S, 2S, 3S)
states in pp collisions are consistent with unpolarised produc-
tion [31], but the Xb spin-alignment is unknown and can have
a strong impact on the efficiency ratio, acceptance ratio, and bin
splitting fractions. Rather than including this as a systematic un-
certainty, upper limits are recalculated under longitudinal (‘LONG’)
and three transverse (‘TRPP’, ‘TRP0’, ‘TRPM’) spin-alignment sce-
narios [48]. Shifts in the upper limits (either up or down) depend
only weakly on mass; the shift is smaller at large masses. In Fig. 4
the effect of each hypothesis is represented by a single number, Data versus simulation differences in the Υ (2S) width param-
eters in the barrel and endcap (1.9% and 4.2%, respectively) are
incorporated as a source of uncertainty, as is the statistical uncer-
tainty on the averages used for signal shape parameters f and r
(0.5–1.4%). 7.3. Upper limit calculation falling in each of the analysis bins. From Eq. (2), the upper limit on
R is proportional to the inverse fitted Υ (2S) yield, N−1
2S , and the
ratios A2S/A and ϵ2S/ϵ. For each source of systematic uncertainty,
the impact on these factors is quantified to find the maximum shift
across the mass range. These are then summed in quadrature and
included in the fit as Gaussian-constrained nuisance parameters. Upper limits are evaluated at the 95% confidence level using
the CLS method by implementing asymptotic formulae for the ˜qμ
statistic [41]. The results (Fig. 4, solid line) range between R = 0.8%
and 4.0%. Median expected upper limits assuming background only
(dashed line), and corresponding ±1σ and ±2σ bands are also
shown. These limits include the effect of systematic uncertainties:
their inclusion increased the observed limits by up to 13% and in-
flated the ±1σ band by 9.5–25%, depending on the Xb mass. The X(3872) →π+π−J/ψ dipion mass distribution favours
high mass [6,9]; for a potential hidden-beauty counterpart this
distribution is unknown. For ψ(2S) →π+π−J/ψ [42], and both
Υ (2S) [39] and Υ (4S) →π+π−Υ (1S) [43,44], the dipion mass
distributions are concentrated near the upper boundary; those for
Y(4260) →π+π−J/ψ [45] and Υ (3S) →π+π−Υ (1S) [40] are
double-humped. The results quoted here assume decay according
to three-body phase space; Υ (2S)- and Υ (3S)-like distributions
change the splitting functions by up to 35%, decrease the efficiency
ratio by up to 17%, and produce modest changes in other parame-
ters. As a check, upper limits are recalculated with modified fitting
ranges (m ± 7σec and m ± 9σec) and doubled bin widths in the
π+π−Υ (1S) mass distributions: shifts are small compared to the
±1σ bands. If an Υ (2S)-like mπ+π−distribution is assumed (cf. CMS [25]), expected upper limits increase: the fractional change is
+17% at 10.1 GeV, and ∼+5% for m > 10.4 GeV. These results exclude Xb states with R = 6.56% for masses
10.05–10.31 GeV and 10.40–11.00 GeV. The expected upper limits
are more restrictive than those from CMS above m ∼10.1 GeV, and
improve as a function of mass; the discrimination in (pT, cosθ∗),
exploited by the binning method, becomes increasingly important
as mass increases. The next largest contribution is due to the linear extrapolation
of the acceptance between the Υ (2S) and Υ (3S) values. 7.2. Systematic uncertainties The upper limit calculation depends indirectly on signal and
background fitting parameters, including the fraction of the signal ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 203 ATLAS Collaboration / Physi
Fig. 3. The solid curve shows the observed local p-value for the background-only hy-
pothesis (left scale), and the corresponding significance, z, of a peak in π+π−Υ (1S)
(right scale), as a function of the mass of a hypothetical Xb parent state. Also
shown are the expected values for the case of a signal with relative production
rates (σB)/(σB)2S of 3% (red, long-dashed) and 6.56% (blue, dashed curve). Fig. 4. Observed 95% CLS
upper limits (solid line) on the relative production
rate R = (σB)/(σB)2S of a hypothetical Xb parent state decaying isotropically to
π+π−Υ (1S), as a function of mass. The median expectation (dashed) and the cor-
responding ±1σ and ±2σ bands (green and yellow respectively) are also shown. The bar on the right shows typical shifts under alternative Xb spin-alignment sce-
narios, relative to the isotropic (‘FLAT’) case shown with the solid point. Fig. 3. The solid curve shows the observed local p-value for the background-only hy-
pothesis (left scale), and the corresponding significance, z, of a peak in π+π−Υ (1S)
(right scale), as a function of the mass of a hypothetical Xb parent state. Also
shown are the expected values for the case of a signal with relative production
rates (σB)/(σB)2S of 3% (red, long-dashed) and 6.56% (blue, dashed curve). Fig. 4. Observed 95% CLS
upper limits (solid line) on the relative production
rate R = (σB)/(σB)2S of a hypothetical Xb parent state decaying isotropically to
π+π−Υ (1S), as a function of mass. The median expectation (dashed) and the cor-
responding ±1σ and ±2σ bands (green and yellow respectively) are also shown. The bar on the right shows typical shifts under alternative Xb spin-alignment sce-
narios, relative to the isotropic (‘FLAT’) case shown with the solid point. Fig. 4. Observed 95% CLS
upper limits (solid line) on the relative production
rate R = (σB)/(σB)2S of a hypothetical Xb parent state decaying isotropically to
π+π−Υ (1S), as a function of mass. The median expectation (dashed) and the cor-
responding ±1σ and ±2σ bands (green and yellow respectively) are also shown. The bar on the right shows typical shifts under alternative Xb spin-alignment sce-
narios, relative to the isotropic (‘FLAT’) case shown with the solid point. Fig. 7.2. Systematic uncertainties 3. The solid curve shows the observed local p-value for the background-only hy-
pothesis (left scale), and the corresponding significance, z, of a peak in π+π−Υ (1S)
(right scale), as a function of the mass of a hypothetical Xb parent state. Also
shown are the expected values for the case of a signal with relative production
rates (σB)/(σB)2S of 3% (red, long-dashed) and 6.56% (blue, dashed curve). 8. Results for the Υ (13D J ) triplet, Υ (10 860), and Υ (11 020) The search described above does not account for the closely
spaced Υ (13D J) triplet or the broad Υ (10 860) and Υ (11 020). To fit for the Υ (13D J), two extra peaks are added to the sig-
nal model. CLEO [18] and BaBar [19] have measured the Υ (13D2)
mass, with an average of (10 163.7 ± 1.4) MeV, but the mass split-
ting within the triplet is unknown. Averaging over several mod-
els [49] leads to triplet masses 10 156, 10 164, and 10 170 MeV
(at 1 MeV precision). A fit is performed using these values, as-
suming independent normalisations but common signal shapes
and bin splitting fractions. A significance of z = 0.12 is found,
with fitted yields −1000 ± 3100, 600 ± 1800, and 800 ± 2300 for
J = 1, 2, and 3. Reasonable changes to the mass splittings do not
appreciably increase the significance, so there appears to be no ev-
idence for Υ (13D J) production. Assuming that J = 2 production
dominates, or that the mass splitting is larger than the experi-
mental resolution, the upper limit on R can be read from Fig. 4;
combined with the measured Υ (13D2) →π+π−Υ (1S) branching
fraction [19], this yields an upper limit on the relative cross section
σ(pp →Υ (13D2))/σ(pp →Υ (2S)) ≤0.55. The crucial computing support from all WLCG partners is ac-
knowledged gratefully, in particular from CERN and the ATLAS Tier-
1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Swe-
den), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy),
NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK) and BNL
(USA) and in the Tier-2 facilities worldwide. (pp
(
))/ (pp
(
))
The signal model for Υ (10 860) and Υ (11 020) is described
in Section 5. Due to the large natural widths of these states,
the fitting range is extended to 10.498–11.198 GeV and the back-
ground polynomial order increased to three. Significances z = 0.6
and z = 0.3 are found for Υ (10 860) and Υ (11 020), for masses
and widths fixed to world-average values [23]. As these parame-
ters have large uncertainties, the significance is also calculated in
a grid of m ± 20 MeV and Γ ± Γ , where Γ is the uncertainty
on the world-average width [23]. 9. Conclusions A search for a hidden-beauty analogue of the X(3872) is
conducted by reconstructing π+π−Υ (1S)(→μ+μ−) events in
16.2 fb−1 of pp collision data recorded at √
s = 8 TeV by ATLAS
at the LHC. To optimise the sensitivity of the search, the analysis
is performed in eight bins of rapidity, transverse momentum, and
the angle (in the rest frame of the parent state) between the di-
pion system and the laboratory-frame momentum of the parent. At each mass, the presence of a signal is tested by performing
simultaneous fits to the nearby π+π−Υ (1S) mass spectrum in
these bins; no evidence for new narrow states is found for masses
10.05–10.31 GeV and 10.40–11.00 GeV. Upper limits are also set
on the ratio R = [σ(pp →Xb)B(Xb →π+π−Υ (1S))]/[σ(pp →
Υ (2S))B(Υ (2S) →π+π−Υ (1S))], with results ranging from 0.8%
to 4.0% depending on the Xb mass. The analogous ratio for the
X(3872) is 6.56%: a value this large is excluded for all Xb masses
considered. Separate fits to the Υ (13D J) triplet, Υ (10 860), and
Υ (11 020) also reveal no significant signals, and a CLS upper limit
of 0.55 is set on σ(pp →Υ (13D2))/σ(pp →Υ (2S)). [5] CMS Collaboration, Measurement of the X(3872) production cross section via
decays to J/ψπ+π−in pp collisions at √
s = 7 TeV, J. High Energy Phys. 1304
(2013) 154, http://dx.doi.org/10.1007/JHEP04(2013)154, arXiv:1302.3968. [6] A. Abulencia, et al., CDF Collaboration, Measurement of the di-pion mass spec-
trum in X(3872) →J/ψπ+π−decays, Phys. Rev. Lett. 96 (2006) 102002,
http://dx.doi.org/10.1103/PhysRevLett.96.102002, arXiv:hep-ex/0512074. [7] B. Aubert, et al., BaBar Collaboration, Search for B+ →X(3872)K +,
X(3872) →J/ψγ , Phys. Rev. D 74 (2006) 071101, http://dx.doi.org/10.1103/
PhysRevD.74.071101, arXiv:hep-ex/0607050. J/ψγ
y
(
)
PhysRevD.74.071101, arXiv:hep-ex/0607050. [8] A. Abulencia, et al., CDF Collaboration, Analysis of the quantum numbers
J PC
of the X(3872), Phys. Rev. Lett. 98 (2007) 132002, http://dx.doi.org/
10.1103/PhysRevLett.98.132002, arXiv:hep-ex/0612053. [9] S.-K. Choi, et al., Belle Collaboration, Bounds on the width, mass difference
and other properties of X(3872) →π+π−J/ψ decays, Phys. Rev. D 84 (2011)
052004, http://dx.doi.org/10.1103/PhysRevD.84.052004, arXiv:1107.0163. [10] R. Aaij, et al., LHCb Collaboration, Determination of the X(3872) meson
quantum numbers, Phys. Rev. Lett. 110 (2013) 222001, http://dx.doi.org/
10.1103/PhysRevLett.110.222001, arXiv:1302.6269. [11] N.A. Tornqvist, From the deuteron to deusons, an analysis of deuteron-like
meson–meson bound states, Z. Phys. C 61 (1994) 525–537, http://dx.doi.org/
10.1007/BF01413192, arXiv:hep-ph/9310247. [12] E.S. Swanson, Short range structure in the X(3872), Phys. Lett. References [1] S.-K. Choi, et al., Belle Collaboration, Observation of a narrow charmoni-
umlike state in exclusive B± →K ±π+π−J/ψ decays, Phys. Rev. Lett. 91
(2003) 262001, http://dx.doi.org/10.1103/PhysRevLett.91.262001, arXiv:hep-ex/
0309032v2. [2] B. Aubert, et al., BaBar Collaboration, Study of the B−→J/ψ K −π+π−de-
cay and measurement of the B−→X(3872)K −branching fraction, Phys. Rev. D 71 (2005) 071103, http://dx.doi.org/10.1103/PhysRevD.71.071103, arXiv:hep-
ex/0406022. [3] D. Acosta, et al., CDF Collaboration, Observation of the narrow state
X(3872) →J/ψπ+π−
in pp
collisions at √
s = 1.96 TeV, Phys. Rev. Lett. 93 (2004) 072001, http://dx.doi.org/10.1103/PhysRevLett.93.072001, arXiv:
hep-ex/0312021. p
/
[4] V. Abazov, et al., DØ Collaboration, Observation and properties of the
X(3872) decaying to J/ψπ+π−in p ¯p collisions at √
s = 1.96 TeV, Phys. Rev. Lett. 93 (2004) 162002, http://dx.doi.org/10.1103/PhysRevLett.93.162002, arXiv:
hep-ex/0405004. 7.3. Upper limit calculation The background shape model is also altered, allow-
ing a third-order term comparable in size to typical values of
the second-order terms. Finally, uncertainties on N2S and the bar-
rel/endcap scaling factor are assigned based on uncertainties from
the Υ (2S) fits. ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 204 chosen as the maximum difference in the median expected signif-
icance from the unpolarised (‘FLAT’) case. chosen as the maximum difference in the median expected signif-
icance from the unpolarised (‘FLAT’) case. We acknowledge the support of ANPCyT, Argentina; YerPhI,
Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azer-
baijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC
and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC,
China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR,
Czech Republic; DNRF, DNSRC and Lundbeck Foundation, Den-
mark; EPLANET, ERC and NSRF, European Union; IN2P3-CNRS,
CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, DFG, HGF, MPG and
AvH Foundation, Germany; GSRT and NSRF, Greece; ISF, MINERVA,
GIF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT and
JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; BRF
and RCN, Norway; MNiSW and NCN, Poland; GRICES and FCT,
Portugal; MNE/IFA, Romania; MES of Russia and ROSATOM, Rus-
sian Federation; JINR; MSTD, Serbia; MSSR, Slovakia; ARRS and
MIZŠ, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and
Wallenberg Foundation, Sweden; SER, SNSF and Cantons of Bern
and Geneva, Switzerland; NSC, Taiwan; TAEK, Turkey; STFC, the
Royal Society and Leverhulme Trust, United Kingdom; DOE and
NSF, United States of America. 9. Conclusions B 588 (2004)
189–195,
http://dx.doi.org/10.1016/j.physletb.2004.03.033,
arXiv:hep-ph/
0311229. 8. Results for the Υ (13D J ) triplet, Υ (10 860), and Υ (11 020) The largest significance for the
Υ (10 860) is z = 1.1 at m = 10 856 MeV and Γ = 55 MeV. For the
Υ (11 020), the largest significance is z = 0.6 at m = 11 039 MeV
and Γ = 95 MeV. Thus, no evidence for Υ (10 860) or Υ (11 020)
production is found. Acknowledgements Alexander,
et
al.,
CLEO
Collaboration,
The
hadronic
transitions
Υ (2S) →Υ (1S), Phys. Rev. D 58 (1998) 052004, http://dx.doi.org/10.1103/
PhysRevD.58.052004, arXiv:hep-ex/9802024. [21] B. Aubert, et al., BaBar Collaboration, Measurement of the e+e−→b¯b cross
section between √
s = 10.54 GeV and 11.20 GeV, Phys. Rev. Lett. 102 (2009)
012001, http://dx.doi.org/10.1103/PhysRevLett.102.012001, arXiv:0809.4120. [40] D. Cronin-Hennessy, et al., CLEO Collaboration, Study of dipion transitions
among Υ (3S), Υ (2S), and Υ (1S) states, Phys. Rev. D 76 (2007) 072001,
http://dx.doi.org/10.1103/PhysRevD.76.072001, arXiv:0706.2317. [22] K.-F. Chen, et al., Belle Collaboration, Observation of anomalous Υ (1S)π+π−
and Υ (2S)π+π−
production near the Υ (5S)
resonance, Phys. Rev. Lett. 100 (2008) 112001, http://dx.doi.org/10.1103/PhysRevLett.100.112001,
arXiv:0710.2577. [41] G. Cowan, K. Cranmer, E. Gross, O. Vitells, Asymptotic formulae for likelihood-
based tests of new physics, Eur. Phys. J. C 71 (2011) 1554, http://dx.doi.org/
10.1140/epjc/s10052-011-1554-0, arXiv:1007.1727. [23] J. Beringer, et al., Particle Data Group, Review of particle physics, Phys. Rev. D
86 (2012) 010001, http://dx.doi.org/10.1103/PhysRevD.86.010001. [42] J. Bai, et al., BES Collaboration, ψ(2S) →π+π−J/ψ
decay distributions,
Phys. Rev. D 62 (2000) 032002, http://dx.doi.org/10.1103/PhysRevD.62.032002,
arXiv:hep-ex/9909038. [24] A. Bondar, et al., Belle Collaboration, Observation of two charged bottomonium-
like resonances in Υ (5S) decays, Phys. Rev. Lett. 108 (2012) 122001, http://
dx.doi.org/10.1103/PhysRevLett.108.122001, arXiv:1110.2251. p
/
[43] B. Aubert, et al., BaBar Collaboration, Observation of Υ (4S)
decays to
π+π−Υ (1S) and π+π−Υ (2S), Phys. Rev. Lett. 96 (2006) 232001, http://
dx.doi.org/10.1103/PhysRevLett.96.232001, arXiv:hep-ex/0604031. g/
/
y
[25] CMS Collaboration, Search for a new bottomonium state decaying to
Υ (1S)π+π−in pp collisions at √
s = 8 TeV, Phys. Lett. B 727 (2013) 57–76,
http://dx.doi.org/10.1016/j.physletb.2013.10.016, arXiv:1309.0250. [44] A. Sokolov, et al., Belle Collaboration, Observation of the decay Υ (4S) →
Υ (1S)π+π−, Phys. Rev. D 75 (2007) 071103, http://dx.doi.org/10.1103/
PhysRevD.75.071103, arXiv:hep-ex/0611026. [26] ATLAS Collaboration, The ATLAS experiment at the CERN large hadron collider,
J. Instrum. 3 (2008) S08003, http://dx.doi.org/10.1088/1748-0221/3/08/S08003. [27] ATLAS Collaboration, Performance of the ATLAS trigger system in 2010, Eur. Phys. J. C 72 (2012) 1849, http://dx.doi.org/10.1140/epjc/s10052-011-1849-1,
arXiv:1110.1530. [45] J. Lees, et al., BaBar Collaboration, Study of the reaction e+e−→
J/ψπ+π−
via
initial-state
radiation
at
BaBar,
Phys. Rev. D
86
(2012)
051102,
http://dx.doi.org/10.1103/PhysRevD.86.051102,
arXiv:1204.2158. [28] ATLAS Collaboration, Summary of ATLAS Pythia 8 tunes, ATL-PHYS-PUB-
2012-003, http://cds.cern.ch/record/1474107. [46] F.-K. Guo, U.-G. Meißner, W. Wang, Production of the bottom analogues and
the spin partner of the X(3872) at hadron colliders, arXiv:1402.6236. [29] T. Sjöstrand, S. Mrenna, P.Z. Skands, A brief introduction to PYTHIA 8.1,
Comput. Acknowledgements [13] L. Maiani, F. Piccinini, A. Polosa, V. Riquer, Diquark–antidiquarks with hidden
or open charm and the nature of X(3872), Phys. Rev. D 71 (2005) 014028,
http://dx.doi.org/10.1103/PhysRevD.71.014028, arXiv:hep-ph/0412098. We thank CERN for the very successful operation of the LHC,
as well as the support staff from our institutions without whom
ATLAS could not be operated efficiently. [14] D. Ebert, R. Faustov, V. Galkin, Masses of heavy tetraquarks in the relativis-
tic quark model, Phys. Lett. B 634 (2006) 214–219, http://dx.doi.org/10.1016/
j.physletb.2006.01.026, arXiv:hep-ph/0512230. ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 205 [32] ATLAS Collaboration, Fast simulation for ATLAS: Atlfast-II and ISF, ATL-SOFT-
PROC-2012-065, http://cds.cern.ch/record/1458503. [15] W.-S. Hou, Searching for the bottom counterparts of X(3872)
and
Y(4260) via π+π−Υ , Phys. Rev. D 74 (2006) 017504, http://dx.doi.org/
10.1103/PhysRevD.74.017504, arXiv:hep-ph/0606016. [33] S. Agostinelli, et al., GEANT4: a simulation toolkit, Nucl. Instrum. Methods
Phys. Res., Sect. A, Accel. Spectrom. Detect. Assoc. Equip. 506 (2003) 250–303,
http://dx.doi.org/10.1016/S0168-9002(03)01368-8. /
y
,
p p /
[16] E.S. Swanson, The new heavy mesons: a status report, Phys. Rep. 429
(2006) 243–305, http://dx.doi.org/10.1016/j.physrep.2006.04.003, arXiv:hep-ph/
0601110. [34] J. Allison, et al., GEANT4 developments and applications, IEEE Trans. Nucl. Sci. 53 (2006) 270, http://dx.doi.org/10.1109/TNS.2006.869826. [17] C.-F. Qiao, F. Yuan, K.-T. Chao, Gluon fragmentation to 3D J
quarkonia,
Phys. Rev. D 55 (1997) 5437–5444, http://dx.doi.org/10.1103/PhysRevD.55.5437,
arXiv:hep-ph/9701249. [35] ATLAS Collaboration, Measurement of upsilon production in 7 TeV pp col-
lisions at ATLAS, Phys. Rev. D 87 (2013) 052004, http://dx.doi.org/10.1103/
PhysRevD.87.052004, arXiv:1211.7255. [18] G. Bonvicini, et al., CLEO Collaboration, First observation of a Υ (1D) state,
Phys. Rev. D 70 (2004) 032001, http://dx.doi.org/10.1103/PhysRevD.70.032001,
arXiv:hep-ex/0404021. [36] CMS Collaboration, Υ (1S), Υ (2S) and Υ (3S) cross section measurements
in pp
collisions at √
s = 7 TeV, CMS-PAS-BPH-12-006, http://cds.cern.ch/
record/1548008. [19] P. del Amo Sanchez, et al., BaBar Collaboration, Observation of the Υ (13D J )
bottomonium state through decays to π+π−Υ (1S), Phys. Rev. D 82 (2010)
111102, http://dx.doi.org/10.1103/PhysRevD.82.111102, arXiv:1004.0175. [37] ATLAS Collaboration, ATLAS tunes of PYTHIA 6 and Pythia 8 for MC11, ATL-
PHYS-PUB-2011-009, http://cds.cern.ch/record/1363300. [20] K.-F. Chen, et al., Belle Collaboration, Observation of an enhancement in
e+e−→Υ (1S)π+π−, Υ (2S)π+π−, and Υ (3S)π+π−
production around
√
s = 10.89 GeV at Belle, Phys. Rev. D 82 (2010) 091106, http://dx.doi.org/
10.1103/PhysRevD.82.091106, arXiv:0810.3829. [38] T. Sjöstrand, S. Mrenna, P.Z. Skands, PYTHIA 6.4 physics and manual, J. High En-
ergy Phys. 0605 (2006) 026, http://dx.doi.org/10.1088/1126-6708/2006/05/026,
arXiv:hep-ph/0603175. [39] J. Acknowledgements Phys. Commun. 178 (2008) 852–867, http://dx.doi.org/10.1016/
j.cpc.2008.01.036, arXiv:0710.3820. [47] M. Karliner, 2014, private communication. [48] ATLAS Collaboration, Measurement of the differential cross-sections of inclu-
sive, prompt and non-prompt J/ψ production in proton–proton collisions
at √
s = 7 TeV, Nucl. Phys. B 850 (2011) 387–444, http://dx.doi.org/10.1016/
j.nuclphysb.2011.05.015, arXiv:1104.3038. [30] J. Pumplin, D. Stump, J. Huston, H.-L. Lai, P.M. Nadolsky, et al., New generation
of parton distributions with uncertainties from global QCD analysis, J. High En-
ergy Phys. 0207 (2002) 012, http://dx.doi.org/10.1088/1126-6708/2002/07/012,
arXiv:hep-ph/0201195. p p /
[31] CMS Collaboration, Measurement of the Υ (1S), Υ (2S), and Υ (3S) polariza-
tions in pp collisions at √
s = 7 TeV, Phys. Rev. Lett. 110 (2013) 081802,
http://dx.doi.org/10.1103/PhysRevLett.110.081802, arXiv:1209.2922. [49] S. Godfrey, J.L. Rosner, Production of the D-wave bb states, Phys. Rev. D 64
(2001) 097501, http://dx.doi.org/10.1103/PhysRevD.64.097501, arXiv:hep-ph/
0105273. ATLAS Collaboration Åkesson 80, G. Akimoto 156, A.V. Akimov 95,
G.L. Alberghi 20a,20b, J. Albert 170, S. Albrand 55, M.J. Alconada Verzini 70, M. Aleksa 30, I.N. Aleksandrov 64
C. Alexa 26a, G. Alexander 154, G. Alexandre 49, T. Alexopoulos 10, M. Alhroob 165a,165c, G. Alimonti 90a,
L. Alio 84, J. Alison 31, B.M.M. Allbrooke 18, L.J. Allison 71, P.P. Allport 73, J. Almond 83, A. Aloisio 103a,103b,
A. Alonso 36, F. Alonso 70, C. Alpigiani 75, A. Altheimer 35, B. Alvarez Gonzalez 89, M.G. Alviggi 103a,103b,
K. Amako 65, Y. Amaral Coutinho 24a, C. Amelung 23, D. Amidei 88, S.P. Amor Dos Santos 125a,125c,
A. Amorim 125a,125b, S. Amoroso 48, N. Amram 154, G. Amundsen 23, C. Anastopoulos 140, L.S. Ancu 49,
N. Andari 30, T. Andeen 35, C.F. Anders 58b, G. Anders 30, K.J. Anderson 31, A. Andreazza 90a,90b,
V. Andrei 58a, X.S. Anduaga 70, S. Angelidakis 9, I. Angelozzi 106, P. Anger 44, A. Angerami 35,
F. Anghinolfi30, A.V. Anisenkov 108,c, N. Anjos 12, A. Annovi 47, A. Antonaki 9, M. Antonelli 47,
A. Antonov 97, J. Antos 145b, F. Anulli 133a, M. Aoki 65, L. Aperio Bella 18, R. Apolle 119,d, G. Arabidze 89,
I. Aracena 144, Y. Arai 65, J.P. Araque 125a, A.T.H. Arce 45, J-F. Arguin 94, S. Argyropoulos 42, M. Arik 19a,
A.J. Armbruster 30, O. Arnaez 30, V. Arnal 81, H. Arnold 48, M. Arratia 28, O. Arslan 21, A. Artamonov 96, G. Aad 84, B. Abbott 112, J. Abdallah 152, S. Abdel Khalek 116, O. Abdinov 11, R. Aben 106, B. Abi 113,
M. Abolins 89, O.S. AbouZeid 159, H. Abramowicz 154, H. Abreu 153, R. Abreu 30, Y. Abulaiti 147a,147b,
B.S. Acharya 165a,165b,a, L. Adamczyk 38a, D.L. Adams 25, J. Adelman 177, S. Adomeit 99, T. Adye 130,
T. Agatonovic-Jovin 13a, J.A. Aguilar-Saavedra 125a,125f, M. Agustoni 17, S.P. Ahlen 22, F. Ahmadov 64,b,
G. Aielli 134a,134b, H. Akerstedt 147a,147b, T.P.A. Åkesson 80, G. Akimoto 156, A.V. Akimov 95,
G.L. Alberghi 20a,20b, J. Albert 170, S. Albrand 55, M.J. Alconada Verzini 70, M. Aleksa 30, I.N. Aleksandrov 64,
C. Alexa 26a, G. Alexander 154, G. Alexandre 49, T. Alexopoulos 10, M. Alhroob 165a,165c, G. Alimonti 90a,
L. Alio 84, J. Alison 31, B.M.M. Allbrooke 18, L.J. Allison 71, P.P. Allport 73, J. Almond 83, A. Aloisio 103a,103b,
A. Alonso 36, F. Alonso 70, C. Alpigiani 75, A. Altheimer 35, B. ATLAS Collaboration G. Aad 84, B. Abbott 112, J. Abdallah 152, S. Abdel Khalek 116, O. Abdinov 11, R. Aben 106, B. Abi 113,
M. Abolins 89, O.S. AbouZeid 159, H. Abramowicz 154, H. Abreu 153, R. Abreu 30, Y. Abulaiti 147a,147b,
B.S. Acharya 165a,165b,a, L. Adamczyk 38a, D.L. Adams 25, J. Adelman 177, S. Adomeit 99, T. Adye 130,
T. Agatonovic-Jovin 13a, J.A. Aguilar-Saavedra 125a,125f, M. Agustoni 17, S.P. Ahlen 22, F. Ahmadov 64,b,
G. Aielli 134a,134b, H. Akerstedt 147a,147b, T.P.A. Åkesson 80, G. Akimoto 156, A.V. Akimov 95,
G.L. Alberghi 20a,20b, J. Albert 170, S. Albrand 55, M.J. Alconada Verzini 70, M. Aleksa 30, I.N. Aleksandrov 6
C. Alexa 26a, G. Alexander 154, G. Alexandre 49, T. Alexopoulos 10, M. Alhroob 165a,165c, G. Alimonti 90a,
L. Alio 84, J. Alison 31, B.M.M. Allbrooke 18, L.J. Allison 71, P.P. Allport 73, J. Almond 83, A. Aloisio 103a,103b,
A. Alonso 36, F. Alonso 70, C. Alpigiani 75, A. Altheimer 35, B. Alvarez Gonzalez 89, M.G. Alviggi 103a,103b,
K. Amako 65, Y. Amaral Coutinho 24a, C. Amelung 23, D. Amidei 88, S.P. Amor Dos Santos 125a,125c,
A. Amorim 125a,125b, S. Amoroso 48, N. Amram 154, G. Amundsen 23, C. Anastopoulos 140, L.S. Ancu 49,
N. Andari 30, T. Andeen 35, C.F. Anders 58b, G. Anders 30, K.J. Anderson 31, A. Andreazza 90a,90b,
V. Andrei 58a, X.S. Anduaga 70, S. Angelidakis 9, I. Angelozzi 106, P. Anger 44, A. Angerami 35,
F. Anghinolfi30, A.V. Anisenkov 108,c, N. Anjos 12, A. Annovi 47, A. Antonaki 9, M. Antonelli 47,
A. Antonov 97, J. Antos 145b, F. Anulli 133a, M. Aoki 65, L. Aperio Bella 18, R. Apolle 119,d, G. Arabidze 89,
I. Aracena 144, Y. Arai 65, J.P. Araque 125a, A.T.H. Arce 45, J-F. Arguin 94, S. Argyropoulos 42, M. Arik 19a,
A.J. Armbruster 30, O. Arnaez 30, V. Arnal 81, H. Arnold 48, M. Arratia 28, O. Arslan 21, A. Artamonov 96, G. Aad 84, B. Abbott 112, J. Abdallah 152, S. Abdel Khalek 116, O. Abdinov 11, R. Aben 106, B. Abi 113,
M. Abolins 89, O.S. AbouZeid 159, H. Abramowicz 154, H. Abreu 153, R. Abreu 30, Y. Abulaiti 147a,147b,
B.S. Acharya 165a,165b,a, L. Adamczyk 38a, D.L. Adams 25, J. Adelman 177, S. Adomeit 99, T. Adye 130,
T. Agatonovic-Jovin 13a, J.A. Aguilar-Saavedra 125a,125f, M. Agustoni 17, S.P. Ahlen 22, F. Ahmadov 64,b,
G. Aielli 134a,134b, H. Akerstedt 147a,147b, T.P.A. ATLAS Collaboration Brendlinger 121, A.J. Brennan 87, R. Brenner 167, S. Bressler 173, K. Bristow 146c, T.M. Bristow 46,
D. Britton 53, F.M. Brochu 28, I. Brock 21, R. Brock 89, C. Bromberg 89, J. Bronner 100, G. Brooijmans 35
T. Brooks 76, W.K. Brooks 32b, J. Brosamer 15, E. Brost 115, J. Brown 55, P.A. Bruckman de Renstrom 39
D. Bruncko 145b, R. Bruneliere 48, S. Brunet 60, A. Bruni 20a, G. Bruni 20a, M. Bruschi 20a, L. Bryngema
T. Buanes 14, Q. Buat 143, F. Bucci 49, P. Buchholz 142, R.M. Buckingham 119, A.G. Buckley 53, S.I. Buda
I.A. Budagov 64, F. Buehrer 48, L. Bugge 118, M.K. Bugge 118, O. Bulekov 97, A.C. Bundock 73, H. Burckh
S. Burdin 73, B. Burghgrave 107, S. Burke 130, I. Burmeister 43, E. Busato 34, D. Büscher 48, V. Büscher 8
P. Bussey 53, C.P. Buszello 167, B. Butler 57, J.M. Butler 22, A.I. Butt 3, C.M. Buttar 53, J.M. Butterworth
P. Butti 106, W. Buttinger 28, A. Buzatu 53, M. Byszewski 10, S. Cabrera Urbán 168, D. Caforio 20a,20b,
O. Cakir 4a, P. Calafiura 15, A. Calandri 137, G. Calderini 79, P. Calfayan 99, R. Calkins 107, L.P. Caloba 24a
D. Calvet 34, S. Calvet 34, R. Camacho Toro 49, S. Camarda 42, D. Cameron 118, L.M. Caminada 15,
R. Caminal Armadans 12, S. Campana 30, M. Campanelli 77, A. Campoverde 149, V. Canale 103a,103b,
A. Canepa 160a, M. Cano Bret 75, J. Cantero 81, R. Cantrill 125a, T. Cao 40, M.D.M. Capeans Garrido 30,
I. Caprini 26a, M. Caprini 26a, M. Capua 37a,37b, R. Caputo 82, R. Cardarelli 134a, T. Carli 30, G. Carlino 10
L. Carminati 90a,90b, S. Caron 105, E. Carquin 32a, G.D. Carrillo-Montoya 146c, J.R. Carter 28,
J. Carvalho 125a,125c, D. Casadei 77, M.P. Casado 12, M. Casolino 12, E. Castaneda-Miranda 146b,
A. Castelli 106, V. Castillo Gimenez 168, N.F. Castro 125a, P. Catastini 57, A. Catinaccio 30, J.R. Catmore 1
A C tt i 30 G C tt
i 134a 134b J C
d
82 V C
li
166 D C
lli 90a M C
lli Sf
12 ,
,
y
,
,
g
,
,
G. Avolio 30, G. Azuelos 94,e, Y. Azuma 156, M.A. Baak 30, A.E. Baas 58a, C. Bacci 135a,135b, H. Bachacou 137,
K. Bachas 155, M. Backes 30, M. Backhaus 30, J. Backus Mayes 144, E. Badescu 26a, P. ATLAS Collaboration Alvarez Gonzalez 89, M.G. Alviggi 103a,103b,
K. Amako 65, Y. Amaral Coutinho 24a, C. Amelung 23, D. Amidei 88, S.P. Amor Dos Santos 125a,125c,
A. Amorim 125a,125b, S. Amoroso 48, N. Amram 154, G. Amundsen 23, C. Anastopoulos 140, L.S. Ancu 49,
N. Andari 30, T. Andeen 35, C.F. Anders 58b, G. Anders 30, K.J. Anderson 31, A. Andreazza 90a,90b,
V. Andrei 58a, X.S. Anduaga 70, S. Angelidakis 9, I. Angelozzi 106, P. Anger 44, A. Angerami 35,
F. Anghinolfi30, A.V. Anisenkov 108,c, N. Anjos 12, A. Annovi 47, A. Antonaki 9, M. Antonelli 47,
A. Antonov 97, J. Antos 145b, F. Anulli 133a, M. Aoki 65, L. Aperio Bella 18, R. Apolle 119,d, G. Arabidze 89,
I. Aracena 144, Y. Arai 65, J.P. Araque 125a, A.T.H. Arce 45, J-F. Arguin 94, S. Argyropoulos 42, M. Arik 19a,
A.J. Armbruster 30, O. Arnaez 30, V. Arnal 81, H. Arnold 48, M. Arratia 28, O. Arslan 21, A. Artamonov 96, ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 206 206
ATLAS Collaboration / Physics Letters B 740 (2015) 199–217
G. Artoni 23, S. Asai 156, N. Asbah 42, A. Ashkenazi 154, B. Åsman 147a,147b, L. Asquith 6, K. Assamagan
R. Astalos 145a, M. Atkinson 166, N.B. Atlay 142, B. Auerbach 6, K. Augsten 127, M. Aurousseau 146b,
G. Avolio 30, G. Azuelos 94,e, Y. Azuma 156, M.A. Baak 30, A.E. Baas 58a, C. Bacci 135a,135b, H. Bachacou
K. Bachas 155, M. Backes 30, M. Backhaus 30, J. Backus Mayes 144, E. Badescu 26a, P. Bagiacchi 133a,133b
P. Bagnaia 133a,133b, Y. Bai 33a, T. Bain 35, J.T. Baines 130, O.K. Baker 177, P. Balek 128, F. Balli 137, E. Ban
Sw. Banerjee 174, A.A.E. Bannoura 176, V. Bansal 170, H.S. Bansil 18, L. Barak 173, S.P. Baranov 95,
E.L. Barberio 87, D. Barberis 50a,50b, M. Barbero 84, T. Barillari 100, M. Barisonzi 176, T. Barklow 144,
N. Barlow 28, B.M. Barnett 130, R.M. Barnett 15, Z. Barnovska 5, A. Baroncelli 135a, G. Barone 49, A.J. Ba
F. Barreiro 81, J. Barreiro Guimarães da Costa 57, R. Bartoldus 144, A.E. Barton 71, P. Bartos 145a,
V. Bartsch 150, A. Bassalat 116, A. Basye 166, R.L. Bates 53, J.R. Batley 28, M. Battaglia 138, M. Battistin 3
F. Bauer 137, H.S. Bawa 144,f , M.D. Beattie 71, T. Beau 79, P.H. Beauchemin 162, R. Beccherle 123a,123b,
P. Bechtle 21, H.P. Beck 17, K. ATLAS Collaboration Becker 176, S. Becker 99, M. Beckingham 171, C. Becot 116, A.J. Beddall 19
A. Beddall 19c, S. Bedikian 177, V.A. Bednyakov 64, C.P. Bee 149, L.J. Beemster 106, T.A. Beermann 176,
M. Begel 25, K. Behr 119, C. Belanger-Champagne 86, P.J. Bell 49, W.H. Bell 49, G. Bella 154, L. Bellagam
A. Bellerive 29, M. Bellomo 85, K. Belotskiy 97, O. Beltramello 30, O. Benary 154, D. Benchekroun 136a,
K. Bendtz 147a,147b, N. Benekos 166, Y. Benhammou 154, E. Benhar Noccioli 49, J.A. Benitez Garcia 160b
D.P. Benjamin 45, J.R. Bensinger 23, K. Benslama 131, S. Bentvelsen 106, D. Berge 106,
E. Bergeaas Kuutmann 167, N. Berger 5, F. Berghaus 170, J. Beringer 15, C. Bernard 22, P. Bernat 77,
C. Bernius 78, F.U. Bernlochner 170, T. Berry 76, P. Berta 128, C. Bertella 84, G. Bertoli 147a,147b,
F. Bertolucci 123a,123b, C. Bertsche 112, D. Bertsche 112, M.I. Besana 90a, G.J. Besjes 105,
O. Bessidskaia 147a,147b, M. Bessner 42, N. Besson 137, C. Betancourt 48, S. Bethke 100, W. Bhimji 46,
R.M. Bianchi 124, L. Bianchini 23, M. Bianco 30, O. Biebel 99, S.P. Bieniek 77, K. Bierwagen 54, J. Biesiad
M. Biglietti 135a, J. Bilbao De Mendizabal 49, H. Bilokon 47, M. Bindi 54, S. Binet 116, A. Bingul 19c,
C. Bini 133a,133b, C.W. Black 151, J.E. Black 144, K.M. Black 22, D. Blackburn 139, R.E. Blair 6,
J.-B. Blanchard 137, T. Blazek 145a, I. Bloch 42, C. Blocker 23, W. Blum 82,∗, U. Blumenschein 54,
G.J. Bobbink 106, V.S. Bobrovnikov 108,c, S.S. Bocchetta 80, A. Bocci 45, C. Bock 99, C.R. Boddy 119,
M. Boehler 48, T.T. Boek 176, J.A. Bogaerts 30, A.G. Bogdanchikov 108, A. Bogouch 91,∗, C. Bohm 147a,
J. Bohm 126, V. Boisvert 76, T. Bold 38a, V. Boldea 26a, A.S. Boldyrev 98, M. Bomben 79, M. Bona 75,
M. Boonekamp 137, A. Borisov 129, G. Borissov 71, M. Borri 83, S. Borroni 42, J. Bortfeldt 99,
V. Bortolotto 135a,135b, K. Bos 106, D. Boscherini 20a, M. Bosman 12, H. Boterenbrood 106, J. Boudreau 1
J. Bouffard 2, E.V. Bouhova-Thacker 71, D. Boumediene 34, C. Bourdarios 116, N. Bousson 113,
S. Boutouil 136d, A. Boveia 31, J. Boyd 30, I.R. Boyko 64, I. Bozic 13a, J. Bracinik 18, A. Brandt 8, G. Brand
O. Brandt 58a, U. Bratzler 157, B. Brau 85, J.E. Brau 115, H.M. Braun 176,∗, S.F. Brazzale 165a,165c, B. Breli
K. ATLAS Collaboration Bagiacchi 133a,133b,
P. Bagnaia 133a,133b, Y. Bai 33a, T. Bain 35, J.T. Baines 130, O.K. Baker 177, P. Balek 128, F. Balli 137, E. Banas 39,
Sw. Banerjee 174, A.A.E. Bannoura 176, V. Bansal 170, H.S. Bansil 18, L. Barak 173, S.P. Baranov 95,
E.L. Barberio 87, D. Barberis 50a,50b, M. Barbero 84, T. Barillari 100, M. Barisonzi 176, T. Barklow 144,
N. Barlow 28, B.M. Barnett 130, R.M. Barnett 15, Z. Barnovska 5, A. Baroncelli 135a, G. Barone 49, A.J. Barr 119,
F. Barreiro 81, J. Barreiro Guimarães da Costa 57, R. Bartoldus 144, A.E. Barton 71, P. Bartos 145a,
V. Bartsch 150, A. Bassalat 116, A. Basye 166, R.L. Bates 53, J.R. Batley 28, M. Battaglia 138, M. Battistin 30,
F. Bauer 137, H.S. Bawa 144,f , M.D. Beattie 71, T. Beau 79, P.H. Beauchemin 162, R. Beccherle 123a,123b,
P. Bechtle 21, H.P. Beck 17, K. Becker 176, S. Becker 99, M. Beckingham 171, C. Becot 116, A.J. Beddall 19c,
A. Beddall 19c, S. Bedikian 177, V.A. Bednyakov 64, C.P. Bee 149, L.J. Beemster 106, T.A. Beermann 176,
M. Begel 25, K. Behr 119, C. Belanger-Champagne 86, P.J. Bell 49, W.H. Bell 49, G. Bella 154, L. Bellagamba 20a,
A. Bellerive 29, M. Bellomo 85, K. Belotskiy 97, O. Beltramello 30, O. Benary 154, D. Benchekroun 136a,
K. Bendtz 147a,147b, N. Benekos 166, Y. Benhammou 154, E. Benhar Noccioli 49, J.A. Benitez Garcia 160b,
D.P. Benjamin 45, J.R. Bensinger 23, K. Benslama 131, S. Bentvelsen 106, D. Berge 106, O. Bessidskaia 147a,147b, M. Bessner 42, N. Besson 137, C. Betancourt 48, S. Bethke 100, W. Bhimji 46, ,
,
,
,
,
g
, J
M. Biglietti 135a, J. Bilbao De Mendizabal 49, H. Bilokon 47, M. Bindi 54, S. Binet 116, A. Bingul 19c,
C. Bini 133a,133b, C.W. Black 151, J.E. Black 144, K.M. Black 22, D. Blackburn 139, R.E. Blair 6, ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 207 L. Cerrito 75, F. Cerutti 15, M. Cerv 30, A. Cervelli 17, S.A. Cetin 19b, A. Chafaq 136a, D. Chakraborty 107,
I. Chalupkova 128, P. Chang 166, B. Chapleau 86, J.D. Chapman 28, D. Charfeddine 116, D.G. Charlton 18,
C.C. Chau 159, C.A. Chavez Barajas 150, S. Cheatham 86, A. Chegwidden 89, S. Chekanov 6,
S.V. Chekulaev 160a, G.A. Chelkov 64,g, M.A. Chelstowska 88, C. Chen 63, H. Chen 25, K. Chen 149,
L. ATLAS Collaboration Chen 33d,h, S. Chen 33c, X. Chen 146c, Y. Chen 66, Y. Chen 35, H.C. Cheng 88, Y. Cheng 31, A. Cheplakov 64,
R. Cherkaoui El Moursli 136e, V. Chernyatin 25,∗, E. Cheu 7, L. Chevalier 137, V. Chiarella 47,
G. Chiefari 103a,103b, J.T. Childers 6, A. Chilingarov 71, G. Chiodini 72a, A.S. Chisholm 18, R.T. Chislett 77,
A. Chitan 26a, M.V. Chizhov 64, S. Chouridou 9, B.K.B. Chow 99, D. Chromek-Burckhart 30, M.L. Chu 152,
J. Chudoba 126, J.J. Chwastowski 39, L. Chytka 114, G. Ciapetti 133a,133b, A.K. Ciftci 4a, R. Ciftci 4a, D. Cinca 53,
V. Cindro 74, A. Ciocio 15, P. Cirkovic 13b, Z.H. Citron 173, M. Citterio 90a, M. Ciubancan 26a, A. Clark 49,
P.J. Clark 46, R.N. Clarke 15, W. Cleland 124, J.C. Clemens 84, C. Clement 147a,147b, Y. Coadou 84,
M. Cobal 165a,165c, A. Coccaro 139, J. Cochran 63, L. Coffey 23, J.G. Cogan 144, J. Coggeshall 166, B. Cole 35,
S. Cole 107, A.P. Colijn 106, J. Collot 55, T. Colombo 58c, G. Colon 85, G. Compostella 100,
P. Conde Muiño 125a,125b, E. Coniavitis 48, M.C. Conidi 12, S.H. Connell 146b, I.A. Connelly 76,
S.M. Consonni 90a,90b, V. Consorti 48, S. Constantinescu 26a, C. Conta 120a,120b, G. Conti 57, F. Conventi 103a,i,
M. Cooke 15, B.D. Cooper 77, A.M. Cooper-Sarkar 119, N.J. Cooper-Smith 76, K. Copic 15, T. Cornelissen 176,
M. Corradi 20a, F. Corriveau 86,j, A. Corso-Radu 164, A. Cortes-Gonzalez 12, G. Cortiana 100, G. Costa 90a,
M.J. Costa 168, D. Costanzo 140, D. Côté 8, G. Cottin 28, G. Cowan 76, B.E. Cox 83, K. Cranmer 109, G. Cree 29,
S. Crépé-Renaudin 55, F. Crescioli 79, W.A. Cribbs 147a,147b, M. Crispin Ortuzar 119, M. Cristinziani 21,
V. Croft 105, G. Crosetti 37a,37b, C.-M. Cuciuc 26a, T. Cuhadar Donszelmann 140, J. Cummings 177,
M. Curatolo 47, C. Cuthbert 151, H. Czirr 142, P. Czodrowski 3, Z. Czyczula 177, S. D’Auria 53, M. D’Onofrio 73,
M.J. Da Cunha Sargedas De Sousa 125a,125b, C. Da Via 83, W. Dabrowski 38a, A. Dafinca 119, T. Dai 88,
O. Dale 14, F. Dallaire 94, C. Dallapiccola 85, M. Dam 36, A.C. Daniells 18, M. Dano Hoffmann 137, V. Dao 48,
G. Darbo 50a, S. Darmora 8, J. Dassoulas 42, A. Dattagupta 60, W. Davey 21, C. David 170, T. Davidek 128,
E. Davies 119,d, M. Davies 154, O. Davignon 79, A.R. Davison 77, P. ATLAS Collaboration Davison 77, Y. Davygora 58a, E. Dawe 143,
I. Dawson 140, R.K. Daya-Ishmukhametova 85, K. De 8, R. de Asmundis 103a, S. De Castro 20a,20b,
S. De Cecco 79, N. De Groot 105, P. de Jong 106, H. De la Torre 81, F. De Lorenzi 63, L. De Nooij 106,
D. De Pedis 133a, A. De Salvo 133a, U. De Sanctis 150, A. De Santo 150, J.B. De Vivie De Regie 116,
W.J. Dearnaley 71, R. Debbe 25, C. Debenedetti 138, B. Dechenaux 55, D.V. Dedovich 64, I. Deigaard 106,
J. Del Peso 81, T. Del Prete 123a,123b, F. Deliot 137, C.M. Delitzsch 49, M. Deliyergiyev 74, A. Dell’Acqua 30,
L. Dell’Asta 22, M. Dell’Orso 123a,123b, M. Della Pietra 103a,i, D. della Volpe 49, M. Delmastro 5,
P.A. Delsart 55, C. Deluca 106, S. Demers 177, M. Demichev 64, A. Demilly 79, S.P. Denisov 129,
D. Derendarz 39, J.E. Derkaoui 136d, F. Derue 79, P. Dervan 73, K. Desch 21, C. Deterre 42, P.O. Deviveiros 106,
A. Dewhurst 130, S. Dhaliwal 106, A. Di Ciaccio 134a,134b, L. Di Ciaccio 5, A. Di Domenico 133a,133b,
C. Di Donato 103a,103b, A. Di Girolamo 30, B. Di Girolamo 30, A. Di Mattia 153, B. Di Micco 135a,135b,
R. Di Nardo 47, A. Di Simone 48, R. Di Sipio 20a,20b, D. Di Valentino 29, F.A. Dias 46, M.A. Diaz 32a,
E.B. Diehl 88, J. Dietrich 42, T.A. Dietzsch 58a, S. Diglio 84, A. Dimitrievska 13a, J. Dingfelder 21,
C. Dionisi 133a,133b, P. Dita 26a, S. Dita 26a, F. Dittus 30, F. Djama 84, T. Djobava 51b, J.I. Djuvsland 58a,
M.A.B. do Vale 24c, A. Do Valle Wemans 125a,125g, D. Dobos 30, C. Doglioni 49, T. Doherty 53, T. Dohmae 156,
J. Dolejsi 128, Z. Dolezal 128, B.A. Dolgoshein 97,∗, M. Donadelli 24d, S. Donati 123a,123b, P. Dondero 120a,120b,
J. Donini 34, J. Dopke 130, A. Doria 103a, M.T. Dova 70, A.T. Doyle 53, M. Dris 10, J. Dubbert 88, S. Dube 15,
E. Dubreuil 34, E. Duchovni 173, G. Duckeck 99, O.A. Ducu 26a, D. Duda 176, A. Dudarev 30, F. Dudziak 63,
L. Duflot 116, L. Duguid 76, M. Dührssen 30, M. Dunford 58a, H. Duran Yildiz 4a, M. Düren 52,
A. Durglishvili 51b, M. Dwuznik 38a, M. Dyndal 38a, J. Ebke 99, W. Edson 2, N.C. Edwards 46, W. Ehrenfeld 21,
T. Eifert 144, G. Eigen 14, K. Einsweiler 15, T. ATLAS Collaboration Ekelof 167, M. El Kacimi 136c, M. Ellert 167, S. Elles 5,
F. Ellinghaus 82, N. Ellis 30, J. Elmsheuser 99, M. Elsing 30, D. Emeliyanov 130, Y. Enari 156, O.C. Endner 82,
117
149
177
17
147
176
2 L. Cerrito 75, F. Cerutti 15, M. Cerv 30, A. Cervelli 17, S.A. Cetin 19b, A. Chafaq 136a, D. Chakraborty 107,
I. Chalupkova 128, P. Chang 166, B. Chapleau 86, J.D. Chapman 28, D. Charfeddine 116, D.G. Charlton 18,
C.C. Chau 159, C.A. Chavez Barajas 150, S. Cheatham 86, A. Chegwidden 89, S. Chekanov 6,
S.V. Chekulaev 160a, G.A. Chelkov 64,g, M.A. Chelstowska 88, C. Chen 63, H. Chen 25, K. Chen 149,
L. Chen 33d,h, S. Chen 33c, X. Chen 146c, Y. Chen 66, Y. Chen 35, H.C. Cheng 88, Y. Cheng 31, A. Cheplakov 64,
R. Cherkaoui El Moursli 136e, V. Chernyatin 25,∗, E. Cheu 7, L. Chevalier 137, V. Chiarella 47,
G. Chiefari 103a,103b, J.T. Childers 6, A. Chilingarov 71, G. Chiodini 72a, A.S. Chisholm 18, R.T. Chislett 77,
A. Chitan 26a, M.V. Chizhov 64, S. Chouridou 9, B.K.B. Chow 99, D. Chromek-Burckhart 30, M.L. Chu 152,
J. Chudoba 126, J.J. Chwastowski 39, L. Chytka 114, G. Ciapetti 133a,133b, A.K. Ciftci 4a, R. Ciftci 4a, D. Cinca 53,
V. Cindro 74, A. Ciocio 15, P. Cirkovic 13b, Z.H. Citron 173, M. Citterio 90a, M. Ciubancan 26a, A. Clark 49,
P.J. Clark 46, R.N. Clarke 15, W. Cleland 124, J.C. Clemens 84, C. Clement 147a,147b, Y. Coadou 84,
M. Cobal 165a,165c, A. Coccaro 139, J. Cochran 63, L. Coffey 23, J.G. Cogan 144, J. Coggeshall 166, B. Cole 35,
S. Cole 107, A.P. Colijn 106, J. Collot 55, T. Colombo 58c, G. Colon 85, G. Compostella 100,
P. Conde Muiño 125a,125b, E. Coniavitis 48, M.C. Conidi 12, S.H. Connell 146b, I.A. Connelly 76,
S.M. Consonni 90a,90b, V. Consorti 48, S. Constantinescu 26a, C. Conta 120a,120b, G. Conti 57, F. Conventi 103a,i,
M. Cooke 15, B.D. Cooper 77, A.M. Cooper-Sarkar 119, N.J. Cooper-Smith 76, K. Copic 15, T. Cornelissen 176,
M. Corradi 20a, F. Corriveau 86,j, A. Corso-Radu 164, A. Cortes-Gonzalez 12, G. Cortiana 100, G. Costa 90a,
M.J. Costa 168, D. Costanzo 140, D. Côté 8, G. Cottin 28, G. Cowan 76, B.E. Cox 83, K. Cranmer 109, G. Cree 29,
S. Crépé-Renaudin 55, F. Crescioli 79, W.A. Cribbs 147a,147b, M. Crispin Ortuzar 119, M. Cristinziani 21,
V. ATLAS Collaboration Croft 105, G. Crosetti 37a,37b, C.-M. Cuciuc 26a, T. Cuhadar Donszelmann 140, J. Cummings 177,
M. Curatolo 47, C. Cuthbert 151, H. Czirr 142, P. Czodrowski 3, Z. Czyczula 177, S. D’Auria 53, M. D’Onofrio 73,
M.J. Da Cunha Sargedas De Sousa 125a,125b, C. Da Via 83, W. Dabrowski 38a, A. Dafinca 119, T. Dai 88,
O. Dale 14, F. Dallaire 94, C. Dallapiccola 85, M. Dam 36, A.C. Daniells 18, M. Dano Hoffmann 137, V. Dao 48,
G. Darbo 50a, S. Darmora 8, J. Dassoulas 42, A. Dattagupta 60, W. Davey 21, C. David 170, T. Davidek 128,
E. Davies 119,d, M. Davies 154, O. Davignon 79, A.R. Davison 77, P. Davison 77, Y. Davygora 58a, E. Dawe 143,
I. Dawson 140, R.K. Daya-Ishmukhametova 85, K. De 8, R. de Asmundis 103a, S. De Castro 20a,20b,
S. De Cecco 79, N. De Groot 105, P. de Jong 106, H. De la Torre 81, F. De Lorenzi 63, L. De Nooij 106,
D. De Pedis 133a, A. De Salvo 133a, U. De Sanctis 150, A. De Santo 150, J.B. De Vivie De Regie 116,
W.J. Dearnaley 71, R. Debbe 25, C. Debenedetti 138, B. Dechenaux 55, D.V. Dedovich 64, I. Deigaard 106,
J. Del Peso 81, T. Del Prete 123a,123b, F. Deliot 137, C.M. Delitzsch 49, M. Deliyergiyev 74, A. Dell’Acqua 30,
L. Dell’Asta 22, M. Dell’Orso 123a,123b, M. Della Pietra 103a,i, D. della Volpe 49, M. Delmastro 5,
P.A. Delsart 55, C. Deluca 106, S. Demers 177, M. Demichev 64, A. Demilly 79, S.P. Denisov 129,
D. Derendarz 39, J.E. Derkaoui 136d, F. Derue 79, P. Dervan 73, K. Desch 21, C. Deterre 42, P.O. Deviveiros 106,
A. Dewhurst 130, S. Dhaliwal 106, A. Di Ciaccio 134a,134b, L. Di Ciaccio 5, A. Di Domenico 133a,133b,
C. Di Donato 103a,103b, A. Di Girolamo 30, B. Di Girolamo 30, A. Di Mattia 153, B. Di Micco 135a,135b,
R. Di Nardo 47, A. Di Simone 48, R. Di Sipio 20a,20b, D. Di Valentino 29, F.A. Dias 46, M.A. Diaz 32a,
E.B. Diehl 88, J. Dietrich 42, T.A. Dietzsch 58a, S. Diglio 84, A. Dimitrievska 13a, J. Dingfelder 21,
C. Dionisi 133a,133b, P. Dita 26a, S. Dita 26a, F. Dittus 30, F. Djama 84, T. Djobava 51b, J.I. Djuvsland 58a,
M.A.B. do Vale 24c, A. Do Valle Wemans 125a,125g, D. Dobos 30, C. Doglioni 49, T. Doherty 53, T. Dohmae 156,
J. ATLAS Collaboration Dolejsi 128, Z. Dolezal 128, B.A. Dolgoshein 97,∗, M. Donadelli 24d, S. Donati 123a,123b, P. Dondero 120a,120b,
J. Donini 34, J. Dopke 130, A. Doria 103a, M.T. Dova 70, A.T. Doyle 53, M. Dris 10, J. Dubbert 88, S. Dube 15,
E. Dubreuil 34, E. Duchovni 173, G. Duckeck 99, O.A. Ducu 26a, D. Duda 176, A. Dudarev 30, F. Dudziak 63,
L. Duflot 116, L. Duguid 76, M. Dührssen 30, M. Dunford 58a, H. Duran Yildiz 4a, M. Düren 52,
A. Durglishvili 51b, M. Dwuznik 38a, M. Dyndal 38a, J. Ebke 99, W. Edson 2, N.C. Edwards 46, W. Ehrenfeld 21,
T. Eifert 144, G. Eigen 14, K. Einsweiler 15, T. Ekelof 167, M. El Kacimi 136c, M. Ellert 167, S. Elles 5,
F. Ellinghaus 82, N. Ellis 30, J. Elmsheuser 99, M. Elsing 30, D. Emeliyanov 130, Y. Enari 156, O.C. Endner 82,
M. Endo 117, R. Engelmann 149, J. Erdmann 177, A. Ereditato 17, D. Eriksson 147a, G. Ernis 176, J. Ernst 2,
M. Ernst 25, J. Ernwein 137, D. Errede 166, S. Errede 166, E. Ertel 82, M. Escalier 116, H. Esch 43, C. Escobar 124, ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 208 ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 209 S. Hillert 21, S.J. Hillier 18, I. Hinchliffe 15, E. Hines 121, M. Hirose 158, D. Hirschbuehl 176, J. Hobbs 149,
N. Hod 106, M.C. Hodgkinson 140, P. Hodgson 140, A. Hoecker 30, M.R. Hoeferkamp 104, F. Hoenig 99,
J. Hoffman 40, D. Hoffmann 84, M. Hohlfeld 82, T.R. Holmes 15, T.M. Hong 121, L. Hooft van Huysduynen 10
W.H. Hopkins 115, Y. Horii 102, J-Y. Hostachy 55, S. Hou 152, A. Hoummada 136a, J. Howard 119, J. Howarth 4
M. Hrabovsky 114, I. Hristova 16, J. Hrivnac 116, T. Hryn’ova 5, C. Hsu 146c, P.J. Hsu 82, S.-C. Hsu 139, D. Hu 35
X. Hu 88, Y. Huang 42, Z. Hubacek 30, F. Hubaut 84, F. Huegging 21, T.B. Huffman 119, E.W. Hughes 35,
G. Hughes 71, M. Huhtinen 30, T.A. Hülsing 82, M. Hurwitz 15, N. Huseynov 64,b, J. Huston 89, J. Huth 57,
G. Iacobucci 49, G. Iakovidis 10, I. Ibragimov 142, L. Iconomidou-Fayard 116, E. Ideal 177, Z. Idrissi 136e,
P. Iengo 103a, O. Igonkina 106, T. Iizawa 172, Y. Ikegami 65, K. Ikematsu 142, M. Ikeno 65, Y. Ilchenko 31,p,
D. Iliadis 155, N. ATLAS Collaboration Ilic 159, Y. Inamaru 66, T. Ince 100, P. Ioannou 9, M. Iodice 135a, K. Iordanidou 9,
V. Ippolito 57, A. Irles Quiles 168, C. Isaksson 167, M. Ishino 67, M. Ishitsuka 158, R. Ishmukhametov 110,
C. Issever 119, S. Istin 19a, J.M. Iturbe Ponce 83, R. Iuppa 134a,134b, J. Ivarsson 80, W. Iwanski 39, H. Iwasaki 6
J.M. Izen 41, V. Izzo 103a, B. Jackson 121, M. Jackson 73, P. Jackson 1, M.R. Jaekel 30, V. Jain 2, K. Jakobs 48,
S. Jakobsen 30, T. Jakoubek 126, J. Jakubek 127, D.O. Jamin 152, D.K. Jana 78, E. Jansen 77, H. Jansen 30,
J. Janssen 21, M. Janus 171, G. Jarlskog 80, N. Javadov 64,b, T. Jav ˚urek 48, L. Jeanty 15, J. Jejelava 51a,q,
G.-Y. Jeng 151, D. Jennens 87, P. Jenni 48,r, J. Jentzsch 43, C. Jeske 171, S. Jézéquel 5, H. Ji 174, J. Jia 149,
Y. Jiang 33b, M. Jimenez Belenguer 42, S. Jin 33a, A. Jinaru 26a, O. Jinnouchi 158, M.D. Joergensen 36,
K.E. Johansson 147a,147b, P. Johansson 140, K.A. Johns 7, K. Jon-And 147a,147b, G. Jones 171, R.W.L. Jones 71,
T.J. Jones 73, J. Jongmanns 58a, P.M. Jorge 125a,125b, K.D. Joshi 83, J. Jovicevic 148, X. Ju 174, C.A. Jung 43,
R.M. Jungst 30, P. Jussel 61, A. Juste Rozas 12,o, M. Kaci 168, A. Kaczmarska 39, M. Kado 116, H. Kagan 110,
M. Kagan 144, E. Kajomovitz 45, C.W. Kalderon 119, S. Kama 40, A. Kamenshchikov 129, N. Kanaya 156,
M. Kaneda 30, S. Kaneti 28, V.A. Kantserov 97, J. Kanzaki 65, B. Kaplan 109, A. Kapliy 31, D. Kar 53,
K. Karakostas 10, N. Karastathis 10, M.J. Kareem 54, M. Karnevskiy 82, S.N. Karpov 64, Z.M. Karpova 64,
K. Karthik 109, V. Kartvelishvili 71, A.N. Karyukhin 129, L. Kashif 174, G. Kasieczka 58b, R.D. Kass 110,
A. Kastanas 14, Y. Kataoka 156, A. Katre 49, J. Katzy 42, V. Kaushik 7, K. Kawagoe 69, T. Kawamoto 156,
G. Kawamura 54, S. Kazama 156, V.F. Kazanin 108, M.Y. Kazarinov 64, R. Keeler 170, R. Kehoe 40, M. Keil 54,
J.S. Keller 42, J.J. Kempster 76, H. Keoshkerian 5, O. Kepka 126, B.P. Kerševan 74, S. Kersten 176, K. Kessoku 15
J. Keung 159, F. Khalil-zada 11, H. Khandanyan 147a,147b, A. Khanov 113, A. Khodinov 97, A. Khomich 58a,
T.J. Khoo 28, G. Khoriauli 21, A. Khoroshilov 176, V. Khovanskiy 96, E. ATLAS Collaboration Khramov 64, J. Khubua 51b, H.Y. Kim 8
H. Kim 147a,147b, S.H. Kim 161, N. Kimura 172, O. Kind 16, B.T. King 73, M. King 168, R.S.B. King 119,
S.B. King 169, J. Kirk 130, A.E. Kiryunin 100, T. Kishimoto 66, D. Kisielewska 38a, F. Kiss 48, T. Kittelmann 124,
K. Kiuchi 161, E. Kladiva 145b, M. Klein 73, U. Klein 73, K. Kleinknecht 82, P. Klimek 147a,147b, A. Klimentov 2
R. Klingenberg 43, J.A. Klinger 83, T. Klioutchnikova 30, P.F. Klok 105, E.-E. Kluge 58a, P. Kluit 106, S. Kluth 100
E. Kneringer 61, E.B.F.G. Knoops 84, A. Knue 53, D. Kobayashi 158, T. Kobayashi 156, M. Kobel 44,
M. Kocian 144, P. Kodys 128, P. Koevesarki 21, T. Koffas 29, E. Koffeman 106, L.A. Kogan 119, S. Kohlmann 176,
Z. Kohout 127, T. Kohriki 65, T. Koi 144, H. Kolanoski 16, I. Koletsou 5, J. Koll 89, A.A. Komar 95,∗,
Y. Komori 156, T. Kondo 65, N. Kondrashova 42, K. Köneke 48, A.C. König 105, S. König 82, T. Kono 65,s,
R. Konoplich 109,t, N. Konstantinidis 77, R. Kopeliansky 153, S. Koperny 38a, L. Köpke 82, A.K. Kopp 48,
K. Korcyl 39, K. Kordas 155, A. Korn 77, A.A. Korol 108,c, I. Korolkov 12, E.V. Korolkova 140, V.A. Korotkov 129,
O. Kortner 100, S. Kortner 100, V.V. Kostyukhin 21, V.M. Kotov 64, A. Kotwal 45, C. Kourkoumelis 9,
V. Kouskoura 155, A. Koutsman 160a, R. Kowalewski 170, T.Z. Kowalski 38a, W. Kozanecki 137, A.S. Kozhin 129
V. Kral 127, V.A. Kramarenko 98, G. Kramberger 74, D. Krasnopevtsev 97, M.W. Krasny 79,
A. Krasznahorkay 30, J.K. Kraus 21, A. Kravchenko 25, S. Kreiss 109, M. Kretz 58c, J. Kretzschmar 73,
K. Kreutzfeldt 52, P. Krieger 159, K. Kroeninger 54, H. Kroha 100, J. Kroll 121, J. Kroseberg 21, J. Krstic 13a,
U. Kruchonak 64, H. Krüger 21, T. Kruker 17, N. Krumnack 63, Z.V. Krumshteyn 64, A. Kruse 174,
M.C. Kruse 45, M. Kruskal 22, T. Kubota 87, H. Kucuk 77, S. Kuday 4a, S. Kuehn 48, A. Kugel 58c, A. Kuhl 138,
T. Kuhl 42, V. Kukhtin 64, Y. Kulchitsky 91, S. Kuleshov 32b, M. Kuna 133a,133b, J. Kunkle 121, A. Kupco 126,
H K
hi
66 Y A K
hki
91 R K
id
66 V K
126 E S K
148 M K
158 J K i
114 yg
y
g
g
L. Lambourne 77, S. ATLAS Collaboration Lammers 60, C.L. Lampen 7, W. Lampl 7, E. Lançon 137, U. Landgraf 48, M.P.J. Landon 75,
V.S. Lang 58a, A.J. Lankford 164, F. Lanni 25, K. Lantzsch 30, S. Laplace 79, C. Lapoire 21, J.F. Laporte 137, 210
ATLAS Collaboration / Physics Letters B 740 (2015) 199–217
T. Lari 90a, F. Lasagni Manghi 20a,20b, M. Lassnig 30, P. Laurelli 47, W. Lavrijsen 15, A.T. Law 138, P. Laycock 7
O. Le Dortz 79, E. Le Guirriec 84, E. Le Menedeu 12, T. LeCompte 6, F. Ledroit-Guillon 55, C.A. Lee 152,
H. Lee 106, J.S.H. Lee 117, S.C. Lee 152, L. Lee 1, G. Lefebvre 79, M. Lefebvre 170, F. Legger 99, C. Leggett 15,
A. Lehan 73, M. Lehmacher 21, G. Lehmann Miotto 30, X. Lei 7, W.A. Leight 29, A. Leisos 155, A.G. Leister 177
M.A.L. Leite 24d, R. Leitner 128, D. Lellouch 173, B. Lemmer 54, K.J.C. Leney 77, T. Lenz 21, G. Lenzen 176,
B. Lenzi 30, R. Leone 7, S. Leone 123a,123b, C. Leonidopoulos 46, S. Leontsinis 10, C. Leroy 94, C.G. Lester 28,
C.M. Lester 121, M. Levchenko 122, J. Levêque 5, D. Levin 88, L.J. Levinson 173, M. Levy 18, A. Lewis 119,
G.H. Lewis 109, A.M. Leyko 21, M. Leyton 41, B. Li 33b,u, B. Li 84, H. Li 149, H.L. Li 31, L. Li 45, L. Li 33e, S. Li 45
Y. Li 33c,v, Z. Liang 138, H. Liao 34, B. Liberti 134a, P. Lichard 30, K. Lie 166, J. Liebal 21, W. Liebig 14,
C. Limbach 21, A. Limosani 87, S.C. Lin 152,w, T.H. Lin 82, F. Linde 106, B.E. Lindquist 149, J.T. Linnemann 89,
E. Lipeles 121, A. Lipniacka 14, M. Lisovyi 42, T.M. Liss 166, D. Lissauer 25, A. Lister 169, A.M. Litke 138,
B. Liu 152, D. Liu 152, J.B. Liu 33b, K. Liu 33b,x, L. Liu 88, M. Liu 45, M. Liu 33b, Y. Liu 33b, M. Livan 120a,120b,
S.S.A. Livermore 119, A. Lleres 55, J. Llorente Merino 81, S.L. Lloyd 75, F. Lo Sterzo 152, E. Lobodzinska 42,
P. Loch 7, W.S. Lockman 138, F.K. Loebinger 83, A.E. Loevschall-Jensen 36, A. Loginov 177, T. Lohse 16,
K. Lohwasser 42, M. Lokajicek 126, V.P. Lombardo 5, B.A. Long 22, J.D. Long 88, R.E. Long 71, L. Lopes 125a,
D. Lopez Mateos 57, B. Lopez Paredes 140, I. Lopez Paz 12, J. Lorenz 99, N. ATLAS Collaboration Lorenzo Martinez 60,
M. Losada 163, P. Loscutoff 15, X. Lou 41, A. Lounis 116, J. Love 6, P.A. Love 71, A.J. Lowe 144,f , F. Lu 33a,
N. Lu 88, H.J. Lubatti 139, C. Luci 133a,133b, A. Lucotte 55, F. Luehring 60, W. Lukas 61, L. Luminari 133a,
O. Lundberg 147a,147b, B. Lund-Jensen 148, M. Lungwitz 82, D. Lynn 25, R. Lysak 126, E. Lytken 80, H. Ma 25,
L.L. Ma 33d, G. Maccarrone 47, A. Macchiolo 100, J. Machado Miguens 125a,125b, D. Macina 30,
D. Madaffari 84, R. Madar 48, H.J. Maddocks 71, W.F. Mader 44, A. Madsen 167, M. Maeno 8, T. Maeno 25,
A. Maevskiy 98, E. Magradze 54, K. Mahboubi 48, J. Mahlstedt 106, S. Mahmoud 73, C. Maiani 137,
C. Maidantchik 24a, A.A. Maier 100, A. Maio 125a,125b,125d, S. Majewski 115, Y. Makida 65, N. Makovec 116,
P. Mal 137,y, B. Malaescu 79, Pa. Malecki 39, V.P. Maleev 122, F. Malek 55, U. Mallik 62, D. Malon 6,
C. Malone 144, S. Maltezos 10, V.M. Malyshev 108, S. Malyukov 30, J. Mamuzic 13b, B. Mandelli 30,
L. Mandelli 90a, I. Mandi´c 74, R. Mandrysch 62, J. Maneira 125a,125b, A. Manfredini 100,
L. Manhaes de Andrade Filho 24b, J.A. Manjarres Ramos 160b, A. Mann 99, P.M. Manning 138,
A. Manousakis-Katsikakis 9, B. Mansoulie 137, R. Mantifel 86, L. Mapelli 30, L. March 146c, J.F. Marchand 29,
G. Marchiori 79, M. Marcisovsky 126, C.P. Marino 170, M. Marjanovic 13a, C.N. Marques 125a,
F. Marroquim 24a, S.P. Marsden 83, Z. Marshall 15, L.F. Marti 17, S. Marti-Garcia 168, B. Martin 30,
B. Martin 89, T.A. Martin 171, V.J. Martin 46, B. Martin dit Latour 14, H. Martinez 137, M. Martinez 12,o,
S. Martin-Haugh 130, A.C. Martyniuk 77, M. Marx 139, F. Marzano 133a, A. Marzin 30, L. Masetti 82,
T. Mashimo 156, R. Mashinistov 95, J. Masik 83, A.L. Maslennikov 108,c, I. Massa 20a,20b, L. Massa 20a,20b,
N. Massol 5, P. Mastrandrea 149, A. Mastroberardino 37a,37b, T. Masubuchi 156, P. Mättig 176, J. Mattmann 8
J. Maurer 26a, S.J. Maxfield 73, D.A. Maximov 108,c, R. Mazini 152, L. Mazzaferro 134a,134b, G. Mc Goldrick 15
S.P. Mc Kee 88, A. McCarn 88, R.L. McCarthy 149, T.G. McCarthy 29, N.A. McCubbin 130, K.W. McFarlane 56,∗
J.A. Mcfayden 77, G. Mchedlidze 54, S.J. McMahon 130, R.A. McPherson 170,j, J. Mechnich 106,
M. Medinnis 42, S. Meehan 31, S. ATLAS Collaboration Mehlhase 99, A. Mehta 73, K. Meier 58a, C. Meineck 99, B. Meirose 80,
C. Melachrinos 31, B.R. Mellado Garcia 146c, F. Meloni 17, A. Mengarelli 20a,20b, S. Menke 100, E. Meoni 162,
K.M. Mercurio 57, S. Mergelmeyer 21, N. Meric 137, P. Mermod 49, L. Merola 103a,103b, C. Meroni 90a,
F.S. Merritt 31, H. Merritt 110, A. Messina 30,z, J. Metcalfe 25, A.S. Mete 164, C. Meyer 82, C. Meyer 121,
J-P. Meyer 137, J. Meyer 30, R.P. Middleton 130, S. Migas 73, L. Mijovi´c 21, G. Mikenberg 173,
M. Mikestikova 126, M. Mikuž 74, A. Milic 30, D.W. Miller 31, C. Mills 46, A. Milov 173, D.A. Milstead 147a,147
D. Milstein 173, A.A. Minaenko 129, Y. Minami 156, I.A. Minashvili 64, A.I. Mincer 109, B. Mindur 38a,
M. Mineev 64, Y. Ming 174, L.M. Mir 12, G. Mirabelli 133a, T. Mitani 172, J. Mitrevski 99, V.A. Mitsou 168,
S. Mitsui 65, A. Miucci 49, P.S. Miyagawa 140, J.U. Mjörnmark 80, T. Moa 147a,147b, K. Mochizuki 84,
S. Mohapatra 35, W. Mohr 48, S. Molander 147a,147b, R. Moles-Valls 168, K. Mönig 42, C. Monini 55,
J. Monk 36, E. Monnier 84, J. Montejo Berlingen 12, F. Monticelli 70, S. Monzani 133a,133b, R.W. Moore 3,
N. Morange 62, D. Moreno 82, M. Moreno Llácer 54, P. Morettini 50a, M. Morgenstern 44, M. Morii 57,
S. Moritz 82, A.K. Morley 148, G. Mornacchi 30, J.D. Morris 75, L. Morvaj 102, H.G. Moser 100, M. Mosidze 51b
J. Moss 110, K. Motohashi 158, R. Mount 144, E. Mountricha 25, S.V. Mouraviev 95,∗, E.J.W. Moyse 85,
S. Muanza 84, R.D. Mudd 18, F. Mueller 58a, J. Mueller 124, K. Mueller 21, T. Mueller 28, T. Mueller 82, ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 210 J
y
, J
y
,
,
g
,
j
,
g
,
M. Mikestikova 126, M. Mikuž 74, A. Milic 30, D.W. Miller 31, C. Mills 46, A. Milov 173, D.A. Milstead 147a,147b,
D. Milstein 173, A.A. Minaenko 129, Y. Minami 156, I.A. Minashvili 64, A.I. Mincer 109, B. Mindur 38a,
M. Mineev 64, Y. Ming 174, L.M. Mir 12, G. Mirabelli 133a, T. Mitani 172, J. Mitrevski 99, V.A. Mitsou 168,
S. Mitsui 65, A. Miucci 49, P.S. Miyagawa 140, J.U. Mjörnmark 80, T. Moa 147a,147b, K. Mochizuki 84,
S. Mohapatra 35, W. Mohr 48, S. Molander 147a,147b, R. Moles-Valls 168, K. ATLAS Collaboration Mönig 42, C. Monini 55,
J. Monk 36, E. Monnier 84, J. Montejo Berlingen 12, F. Monticelli 70, S. Monzani 133a,133b, R.W. Moore 3,
N. Morange 62, D. Moreno 82, M. Moreno Llácer 54, P. Morettini 50a, M. Morgenstern 44, M. Morii 57,
S. Moritz 82, A.K. Morley 148, G. Mornacchi 30, J.D. Morris 75, L. Morvaj 102, H.G. Moser 100, M. Mosidze 51b,
J. Moss 110, K. Motohashi 158, R. Mount 144, E. Mountricha 25, S.V. Mouraviev 95,∗, E.J.W. Moyse 85,
S. Muanza 84, R.D. Mudd 18, F. Mueller 58a, J. Mueller 124, K. Mueller 21, T. Mueller 28, T. Mueller 82, ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 211 ATLAS Collaboration / Physics Letters B 740 (2015) 199–217
2
D. Muenstermann 49, Y. Munwes 154, J.A. Murillo Quijada 18, W.J. Murray 171,130, H. Musheghyan 54,
E. Musto 153, A.G. Myagkov 129,aa, M. Myska 127, O. Nackenhorst 54, J. Nadal 54, K. Nagai 61, R. Nagai 158,
Y. Nagai 84, K. Nagano 65, A. Nagarkar 110, Y. Nagasaka 59, M. Nagel 100, A.M. Nairz 30, Y. Nakahama 30,
K. Nakamura 65, T. Nakamura 156, I. Nakano 111, H. Namasivayam 41, G. Nanava 21, R. Narayan 58b,
T. Nattermann 21, T. Naumann 42, G. Navarro 163, R. Nayyar 7, H.A. Neal 88, P.Yu. Nechaeva 95, T.J. Neep 83,
P.D. Nef 144, A. Negri 120a,120b, G. Negri 30, M. Negrini 20a, S. Nektarijevic 49, C. Nellist 116, A. Nelson 164,
T.K. Nelson 144, S. Nemecek 126, P. Nemethy 109, A.A. Nepomuceno 24a, M. Nessi 30,ab, M.S. Neubauer 166,
M. Neumann 176, R.M. Neves 109, P. Nevski 25, P.R. Newman 18, D.H. Nguyen 6, R.B. Nickerson 119,
R. Nicolaidou 137, B. Nicquevert 30, J. Nielsen 138, N. Nikiforou 35, A. Nikiforov 16, V. Nikolaenko 129,aa,
I. Nikolic-Audit 79, K. Nikolics 49, K. Nikolopoulos 18, P. Nilsson 8, Y. Ninomiya 156, A. Nisati 133a,
R. Nisius 100, T. Nobe 158, L. Nodulman 6, M. Nomachi 117, I. Nomidis 29, S. Norberg 112, M. Nordberg 30,
O. Novgorodova 44, S. Nowak 100, M. Nozaki 65, L. Nozka 114, K. Ntekas 10, G. Nunes Hanninger 87,
T. Nunnemann 99, E. Nurse 77, F. Nuti 87, B.J. O’Brien 46, F. O’grady 7, D.C. O’Neil 143, V. O’Shea 53,
F.G. Oakham 29,e, H. Oberlack 100, T. Obermann 21, J. Ocariz 79, A. Ochi 66, M.I. Ochoa 77, S. Oda 69,
S. Odaka 65, H. ATLAS Collaboration Ogren 60, A. Oh 83, S.H. Oh 45, C.C. Ohm 15, H. Ohman 167, W. Okamura 117, H. Okawa 25,
Y. Okumura 31, T. Okuyama 156, A. Olariu 26a, A.G. Olchevski 64, S.A. Olivares Pino 46,
D. Oliveira Damazio 25, E. Oliver Garcia 168, A. Olszewski 39, J. Olszowska 39, A. Onofre 125a,125e,
P.U.E. Onyisi 31,p, C.J. Oram 160a, M.J. Oreglia 31, Y. Oren 154, D. Orestano 135a,135b, N. Orlando 72a,72b,
C. Oropeza Barrera 53, R.S. Orr 159, B. Osculati 50a,50b, R. Ospanov 121, G. Otero y Garzon 27, H. Otono 69,
M. Ouchrif 136d, E.A. Ouellette 170, F. Ould-Saada 118, A. Ouraou 137, K.P. Oussoren 106, Q. Ouyang 33a,
A. Ovcharova 15, M. Owen 83, V.E. Ozcan 19a, N. Ozturk 8, K. Pachal 119, A. Pacheco Pages 12,
C. Padilla Aranda 12, M. Pagáˇcová 48, S. Pagan Griso 15, E. Paganis 140, C. Pahl 100, F. Paige 25, P. Pais 85,
K. Pajchel 118, G. Palacino 160b, S. Palestini 30, M. Palka 38b, D. Pallin 34, A. Palma 125a,125b, J.D. Palmer 18,
Y.B. Pan 174, E. Panagiotopoulou 10, J.G. Panduro Vazquez 76, P. Pani 106, N. Panikashvili 88, S. Panitkin 25,
D. Pantea 26a, L. Paolozzi 134a,134b, Th.D. Papadopoulou 10, K. Papageorgiou 155,m, A. Paramonov 6,
D. Paredes Hernandez 155, M.A. Parker 28, F. Parodi 50a,50b, J.A. Parsons 35, U. Parzefall 48,
E. Pasqualucci 133a, S. Passaggio 50a, A. Passeri 135a, F. Pastore 135a,135b,∗, Fr. Pastore 76, G. Pásztor 29,
S. Pataraia 176, N.D. Patel 151, J.R. Pater 83, S. Patricelli 103a,103b, T. Pauly 30, J. Pearce 170, L.E. Pedersen 36,
M. Pedersen 118, S. Pedraza Lopez 168, R. Pedro 125a,125b, S.V. Peleganchuk 108, D. Pelikan 167, H. Peng 33b,
B. Penning 31, J. Penwell 60, D.V. Perepelitsa 25, E. Perez Codina 160a, M.T. Pérez García-Estañ 168,
V. Perez Reale 35, L. Perini 90a,90b, H. Pernegger 30, S. Perrella 103a,103b, R. Perrino 72a, R. Peschke 42,
V.D. Peshekhonov 64, K. Peters 30, R.F.Y. Peters 83, B.A. Petersen 30, T.C. Petersen 36, E. Petit 42,
A. Petridis 147a,147b, C. Petridou 155, E. Petrolo 133a, F. Petrucci 135a,135b, N.E. Pettersson 158, R. Pezoa 32b,
P.W. Phillips 130, G. Piacquadio 144, E. Pianori 171, A. Picazio 49, E. Piccaro 75, M. Piccinini 20a,20b,
R. Piegaia 27, D.T. Pignotti 110, J.E. Pilcher 31, A.D. Pilkington 77, J. Pina 125a,125b,125d,
M. Pinamonti 165a,165c,ac, A. Pinder 119, J.L. Pinfold 3, A. Pingel 36, B. ATLAS Collaboration Pinto 125a, S. Pires 79, M. Pitt 173,
C. Pizio 90a,90b, L. Plazak 145a, M.-A. Pleier 25, V. Pleskot 128, E. Plotnikova 64, P. Plucinski 147a,147b,
S. Poddar 58a, F. Podlyski 34, R. Poettgen 82, L. Poggioli 116, D. Pohl 21, M. Pohl 49, G. Polesello 120a,
A. Policicchio 37a,37b, R. Polifka 159, A. Polini 20a, C.S. Pollard 45, V. Polychronakos 25, K. Pommès 30,
L. Pontecorvo 133a, B.G. Pope 89, G.A. Popeneciu 26b, D.S. Popovic 13a, A. Poppleton 30, X. Portell Bueso 12,
S. Pospisil 127, K. Potamianos 15, I.N. Potrap 64, C.J. Potter 150, C.T. Potter 115, G. Poulard 30, J. Poveda 60,
V. Pozdnyakov 64, P. Pralavorio 84, A. Pranko 15, S. Prasad 30, R. Pravahan 8, S. Prell 63, D. Price 83, J. Price 7
L.E. Price 6, D. Prieur 124, M. Primavera 72a, M. Proissl 46, K. Prokofiev 47, F. Prokoshin 32b,
E. Protopapadaki 137, S. Protopopescu 25, J. Proudfoot 6, M. Przybycien 38a, H. Przysiezniak 5, E. Ptacek 115
D. Puddu 135a,135b, E. Pueschel 85, D. Puldon 149, M. Purohit 25,ad, P. Puzo 116, J. Qian 88, G. Qin 53, Y. Qin 83
A. Quadt 54, D.R. Quarrie 15, W.B. Quayle 165a,165b, M. Queitsch-Maitland 83, D. Quilty 53, A. Qureshi 160b,
V. Radeka 25, V. Radescu 42, S.K. Radhakrishnan 149, P. Radloff 115, P. Rados 87, F. Ragusa 90a,90b,
G. Rahal 179, S. Rajagopalan 25, M. Rammensee 30, A.S. Randle-Conde 40, C. Rangel-Smith 167, K. Rao 164,
F Rauscher 99 T C Rave 48 T Ravenscroft 53 M Raymond 30 A L Read 118 N P Readioff 73 ,
,
y
,
,
,
20b, A. Redelbach 175, G. Redlinger 25, R. Reece 138, K. Reeves 41, L. Rehnisch 16, H. Reisin
, M. Relich
, C. Rembser
, H. Ren
, Z.L. Ren
, A. Renaud
, M. Rescigno
,
S. Resconi 90a, O.L. Rezanova 108,c, P. Reznicek 128, R. Rezvani 94, R. Richter 100, M. Ridel 79, P. Rieck 16, ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 212 212
ATLAS Collaboration / Physics Letters B 740 (2015) 199 217
J. Rieger 54, M. Rijssenbeek 149, A. Rimoldi 120a,120b, L. Rinaldi 20a, E. Ritsch 61, I. Riu 12, F. Rizatdinova 113,
E. Rizvi 75, S.H. Robertson 86,j, A. Robichaud-Veronneau 86, D. Robinson 28, J.E.M. Robinson 83,
A. Robson 53, C. Roda 123a,123b, L. Rodrigues 30, S. Roe 30, O. ATLAS Collaboration Røhne 118, S. Rolli 162, A. Romaniouk 97,
M. Romano 20a,20b, E. Romero Adam 168, N. Rompotis 139, M. Ronzani 48, L. Roos 79, E. Ros 168,
S. Rosati 133a, K. Rosbach 49, M. Rose 76, P. Rose 138, P.L. Rosendahl 14, O. Rosenthal 142, V. Rossetti 147a,147b,
E. Rossi 103a,103b, L.P. Rossi 50a, R. Rosten 139, M. Rotaru 26a, I. Roth 173, J. Rothberg 139, D. Rousseau 116,
C.R. Royon 137, A. Rozanov 84, Y. Rozen 153, X. Ruan 146c, F. Rubbo 12, I. Rubinskiy 42, V.I. Rud 98,
C. Rudolph 44, M.S. Rudolph 159, F. Rühr 48, A. Ruiz-Martinez 30, Z. Rurikova 48, N.A. Rusakovich 64,
A. Ruschke 99, J.P. Rutherfoord 7, N. Ruthmann 48, Y.F. Ryabov 122, M. Rybar 128, G. Rybkin 116,
N.C. Ryder 119, A.F. Saavedra 151, S. Sacerdoti 27, A. Saddique 3, I. Sadeh 154, H.F-W. Sadrozinski 138,
R. Sadykov 64, F. Safai Tehrani 133a, H. Sakamoto 156, Y. Sakurai 172, G. Salamanna 135a,135b,
A. Salamon 134a, M. Saleem 112, D. Salek 106, P.H. Sales De Bruin 139, D. Salihagic 100, A. Salnikov 144,
J. Salt 168, D. Salvatore 37a,37b, F. Salvatore 150, A. Salvucci 105, A. Salzburger 30, D. Sampsonidis 155,
A. Sanchez 103a,103b, J. Sánchez 168, V. Sanchez Martinez 168, H. Sandaker 14, R.L. Sandbach 75,
H.G. Sander 82, M.P. Sanders 99, M. Sandhoff 176, T. Sandoval 28, C. Sandoval 163, R. Sandstroem 100,
D.P.C. Sankey 130, A. Sansoni 47, C. Santoni 34, R. Santonico 134a,134b, H. Santos 125a, I. Santoyo Castillo 150,
K. Sapp 124, A. Sapronov 64, J.G. Saraiva 125a,125d, B. Sarrazin 21, G. Sartisohn 176, O. Sasaki 65, Y. Sasaki 156,
G. Sauvage 5,∗, E. Sauvan 5, P. Savard 159,e, D.O. Savu 30, C. Sawyer 119, L. Sawyer 78,n, D.H. Saxon 53,
J. Saxon 121, C. Sbarra 20a, A. Sbrizzi 20a,20b, T. Scanlon 77, D.A. Scannicchio 164, M. Scarcella 151,
V. Scarfone 37a,37b, J. Schaarschmidt 173, P. Schacht 100, D. Schaefer 30, R. Schaefer 42, S. Schaepe 21,
S. Schaetzel 58b, U. Schäfer 82, A.C. Schaffer 116, D. Schaile 99, R.D. Schamberger 149, V. Scharf 58a,
V.A. Schegelsky 122, D. Scheirich 128, M. Schernau 164, M.I. Scherzer 35, C. Schiavi 50a,50b, J. Schieck 99,
C. Schillo 48, M. Schioppa 37a,37b, S. Schlenker 30, E. Schmidt 48, K. Schmieden 30, C. Schmitt 82,
S. Schmitt 58b, B. Schneider 17, Y.J. Schnellbach 73, U. Schnoor 44, L. Schoeffel 137, A. ATLAS Collaboration Schoening 58b,
B.D. Schoenrock 89, A.L.S. Schorlemmer 54, M. Schott 82, D. Schouten 160a, J. Schovancova 25,
S. Schramm 159, M. Schreyer 175, C. Schroeder 82, N. Schuh 82, M.J. Schultens 21, H.-C. Schultz-Coulon 58a,
H. Schulz 16, M. Schumacher 48, B.A. Schumm 138, Ph. Schune 137, C. Schwanenberger 83,
A. Schwartzman 144, T.A. Schwarz 88, Ph. Schwegler 100, Ph. Schwemling 137, R. Schwienhorst 89,
J. Schwindling 137, T. Schwindt 21, M. Schwoerer 5, F.G. Sciacca 17, E. Scifo 116, G. Sciolla 23, W.G. Scott 130,
F. Scuri 123a,123b, F. Scutti 21, J. Searcy 88, G. Sedov 42, E. Sedykh 122, S.C. Seidel 104, A. Seiden 138,
F. Seifert 127, J.M. Seixas 24a, G. Sekhniaidze 103a, S.J. Sekula 40, K.E. Selbach 46, D.M. Seliverstov 122,∗,
G. Sellers 73, N. Semprini-Cesari 20a,20b, C. Serfon 30, L. Serin 116, L. Serkin 54, T. Serre 84, R. Seuster 160a,
H. Severini 112, T. Sfiligoj 74, F. Sforza 100, A. Sfyrla 30, E. Shabalina 54, M. Shamim 115, L.Y. Shan 33a,
R. Shang 166, J.T. Shank 22, M. Shapiro 15, P.B. Shatalov 96, K. Shaw 165a,165b, C.Y. Shehu 150, P. Sherwood 77,
L. Shi 152,ae, S. Shimizu 66, C.O. Shimmin 164, M. Shimojima 101, M. Shiyakova 64, A. Shmeleva 95,
M.J. Shochet 31, D. Short 119, S. Shrestha 63, E. Shulga 97, M.A. Shupe 7, S. Shushkevich 42, P. Sicho 126,
O. Sidiropoulou 155, D. Sidorov 113, A. Sidoti 133a, F. Siegert 44, Dj. Sijacki 13a, J. Silva 125a,125d, Y. Silver 154,
D. Silverstein 144, S.B. Silverstein 147a, V. Simak 127, O. Simard 5, Lj. Simic 13a, S. Simion 116, E. Simioni 82,
B. Simmons 77, R. Simoniello 90a,90b, M. Simonyan 36, P. Sinervo 159, N.B. Sinev 115, V. Sipica 142,
G. Siragusa 175, A. Sircar 78, A.N. Sisakyan 64,∗, S.Yu. Sivoklokov 98, J. Sjölin 147a,147b, T.B. Sjursen 14,
H.P. Skottowe 57, K.Yu. Skovpen 108, P. Skubic 112, M. Slater 18, T. Slavicek 127, K. Sliwa 162, V. Smakhtin 173,
B.H. Smart 46, L. Smestad 14, S.Yu. Smirnov 97, Y. Smirnov 97, L.N. Smirnova 98,af , O. Smirnova 80,
K.M. Smith 53, M. Smizanska 71, K. Smolek 127, A.A. Snesarev 95, G. Snidero 75, S. Snyder 25, R. Sobie 170,j,
F. Socher 44, A. Soffer 154, D.A. Soh 152,ae, C.A. Solans 30, M. Solar 127, J. Solc 127, E.Yu. Soldatov 97,
U. Soldevila 168, A.A. Solodkov 129, A. Soloshenko 64, O.V. Solovyanov 129, V. ATLAS Collaboration Solovyev 122, P. Sommer 48,
H.Y. Song 33b, N. Soni 1, A. Sood 15, A. Sopczak 127, B. Sopko 127, V. Sopko 127, V. Sorin 12, M. Sosebee 8,
R. Soualah 165a,165c, P. Soueid 94, A.M. Soukharev 108,c, D. South 42, S. Spagnolo 72a,72b, F. Spanò 76,
W.R. Spearman 57, F. Spettel 100, R. Spighi 20a, G. Spigo 30, L.A. Spiller 87, M. Spousta 128, T. Spreitzer 159,
B. Spurlock 8, R.D. St. Denis 53,∗, S. Staerz 44, J. Stahlman 121, R. Stamen 58a, S. Stamm 16, E. Stanecka 39,
R.W. Stanek 6, C. Stanescu 135a, M. Stanescu-Bellu 42, M.M. Stanitzki 42, S. Stapnes 118, E.A. Starchenko 129,
J. Stark 55, P. Staroba 126, P. Starovoitov 42, R. Staszewski 39, P. Stavina 145a,∗, P. Steinberg 25, B. Stelzer 143,
H.J. Stelzer 30, O. Stelzer-Chilton 160a, H. Stenzel 52, S. Stern 100, G.A. Stewart 53, J.A. Stillings 21, J. Rieger 54, M. Rijssenbeek 149, A. Rimoldi 120a,120b, L. Rinaldi 20a, E. Ritsch 61, I. Riu 12, F. Rizatdinova 113, . Rizvi 75, S.H. Robertson 86,j, A. Robichaud-Veronneau 86, D. Robinson 28, J.E.M. Ro
b . Robson 53, C. Roda 123a,123b, L. Rodrigues 30, S. Roe 30, O. Røhne 118, S. Rolli 162, A ,
,
,
,
,
E. Rossi 103a,103b, L.P. Rossi 50a, R. Rosten 139, M. Rotaru 26a, I. Roth 173, J. Rothber J
C.R. Royon 137, A. Rozanov 84, Y. Rozen 153, X. Ruan 146c, F. Rubbo 12, I. Rubinskiy
44
159
48
30
48 ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 213 K. Suruliz 150, G. Susinno 37a,37b, M.R. Sutton 150, Y. Suzuki 65, M. Svatos 126, S. Swedish 169,
M. Swiatlowski 144, I. Sykora 145a, T. Sykora 128, D. Ta 89, C. Taccini 135a,135b, K. Tackmann 42, J. Taenzer 159,
A. Taffard 164, R. Tafirout 160a, N. Taiblum 154, H. Takai 25, R. Takashima 68, H. Takeda 66, T. Takeshita 141,
Y Takubo 65 M Talby 84 A A Talyshev 108,c J Y C Tam 175 K G Tan 87 J Tanaka 156 R Tanaka 116 J. Therhaag 21, T. Theveneaux-Pelzer 34, J.P. Thomas 18, J. Thomas-Wilsker 76, E.N. Thompson 35, ,
,
y y
,
,
,
,
S.A. Tupputi 20a,20b, S. Turchikhin 98,af , D. Turecek 127, I. Turk Cakir 4d, R. Turra 90a,90b, P.M. Tuts 35,
A. Tykhonov 49, M. Tylmad 147a,147b, M. Tyndel 130, K. Uchida 21, I. ATLAS Collaboration Ueda 156, R. Ueno 29, M. Ughetto 84,
M. Ugland 14, M. Uhlenbrock 21, F. Ukegawa 161, G. Unal 30, A. Undrus 25, G. Unel 164, F.C. Ungaro 48,
Y. Unno 65, C. Unverdorben 99, D. Urbaniec 35, P. Urquijo 87, G. Usai 8, A. Usanova 61, L. Vacavant 84,
V. Vacek 127, B. Vachon 86, N. Valencic 106, S. Valentinetti 20a,20b, A. Valero 168, L. Valery 34, S. Valkar 128,
E. Valladolid Gallego 168, S. Vallecorsa 49, J.A. Valls Ferrer 168, W. Van Den Wollenberg 106, ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 214 C. Weiser 48, H. Weits 106, P.S. Wells 30, T. Wenaus 25, D. Wendland 16, Z. Weng 152,ae, T. Wengler 30,
S. Wenig 30, N. Wermes 21, M. Werner 48, P. Werner 30, M. Wessels 58a, J. Wetter 162, K. Whalen 29,
A. White 8, M.J. White 1, R. White 32b, S. White 123a,123b, D. Whiteson 164, D. Wicke 176, F.J. Wickens 130,
W. Wiedenmann 174, M. Wielers 130, P. Wienemann 21, C. Wiglesworth 36, L.A.M. Wiik-Fuchs 21,
P.A. Wijeratne 77, A. Wildauer 100, M.A. Wildt 42,ak, H.G. Wilkens 30, J.Z. Will 99, H.H. Williams 121,
S. Williams 28, C. Willis 89, S. Willocq 85, A. Wilson 88, J.A. Wilson 18, I. Wingerter-Seez 5,
F. Winklmeier 115, B.T. Winter 21, M. Wittgen 144, T. Wittig 43, J. Wittkowski 99, S.J. Wollstadt 82,
M.W. Wolter 39, H. Wolters 125a,125c, B.K. Wosiek 39, J. Wotschack 30, M.J. Woudstra 83, K.W. Wozniak 39,
M. Wright 53, M. Wu 55, S.L. Wu 174, X. Wu 49, Y. Wu 88, E. Wulf 35, T.R. Wyatt 83, B.M. Wynne 46,
S. Xella 36, M. Xiao 137, D. Xu 33a, L. Xu 33b,al, B. Yabsley 151, S. Yacoob 146b,am, R. Yakabe 66, M. Yamada 65,
H. Yamaguchi 156, Y. Yamaguchi 117, A. Yamamoto 65, K. Yamamoto 63, S. Yamamoto 156, T. Yamamura 156,
T. Yamanaka 156, K. Yamauchi 102, Y. Yamazaki 66, Z. Yan 22, H. Yang 33e, H. Yang 174, U.K. Yang 83,
Y. Yang 110, S. Yanush 92, L. Yao 33a, W-M. Yao 15, Y. Yasu 65, E. Yatsenko 42, K.H. Yau Wong 21, J. Ye 40,
S. Ye 25, I. Yeletskikh 64, A.L. Yen 57, E. Yildirim 42, M. Yilmaz 4b, R. Yoosoofmiya 124, K. Yorita 172,
R. Yoshida 6, K. Yoshihara 156, C. Young 144, C.J.S. Young 30, S. Youssef 22, D.R. Yu 15, J. Turkey 21 Physikalisches Institut, University of Bonn, Bonn, Germany 22 Department of Physics, Boston University, Boston, MA, United States 22 Department of Physics, Boston University, Boston, MA, United States 3 Department of Physics, Brandeis University, Waltham, MA, United Stat p
f
y
,
y,
,
,
24 (a) Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro; (b) Electrical Circuits Department, Federal University of Juiz de Fora (UFJF), Juiz de Fora; (c) Federal University of
Sao Joao del Rei (UFSJ), Sao Joao del Rei; (d) Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo, Brazil
25 p
f
y
y
24 (a) Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro; (b) Electrical Circuits Department, Federal University of Juiz de Fora
(d) 24 (a) Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro; (b) Electrical Circuits Department 24 (a) Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro; (b) Electrical Circuits Department, Federal University of Juiz de Fora (UFJF), Juiz de Fora; (c) Federal University of
Sao Joao del Rei (UFSJ), Sao Joao del Rei; (d) Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo, Brazil 4 (a) Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro; J
/
/
J
p
Sao Joao del Rei (UFSJ), Sao Joao del Rei; (d) Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo, Brazil Sao Joao del Rei (UFSJ), Sao Joao del Rei; (d) Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo, Brazil Sao Joao del Rei (UFSJ), Sao Joao del Rei; (d) Instituto de Fisica, Univers ysics Department, Brookhaven National Laboratory, Upton, NY, United St Physics Department, Brookhaven National Laboratory, Upton, NY, United States
26 (a) National Institute of Physics and Nuclear Engineering, Bucharest; (b) National Institute for Research and Development of Isotopic and Molecular Technologies, Physics Department,
Cluj Napoca; (c) University Politehnica Bucharest, Bucharest; (d) West University in Timisoara, Timisoara, Romania
27 onal Laboratory, Upton, NY, United States
uclear Engineering, Bucharest; (b) National Institute for Research and Development of Isotopic and Molecular Technologies, Physics Department,
ucharest, Bucharest; (d) West University in Timisoara, Timisoara, Romania y
p
,
y,
p
,
,
26 (a) National Institute of Physics and Nuclear Engineering, Bucharest; (b) National Institute for Research and Development of Isotopic and Molecular Technologies, Physics Department,
Cluj Napoca; (c) University Politehnica Bucharest, Bucharest; (d) West University in Timisoara, Timisoara, Romania ,
y,
p
,
,
nstitute of Physics and Nuclear Engineering, Bucharest; (b) National Institute for Research and Development of Isotopic and Molecular Technolog
University Politehnica Bucharest Bucharest; (d) West University in Timisoara Timisoara Romania 26 (a) National Institute of Physics and Nuclear Engineering, Bucharest; (b) National Institute for Research and Development of Isotopic and M
( )
(d) 26 (a) National Institute of Physics and Nuclear Engineering, Bucharest; (b) National Institute for Research a 6 (a) National Institute of Physics and Nuclear Engineering, Bucharest; (b f
y
g
g,
;
f
p
f
p
g
,
y
p
,
Cluj Napoca; (c) University Politehnica Bucharest, Bucharest; (d) West University in Timisoara, Timisoara, Romania Cluj Napoca; (c) University Politehnica Bucharest, Bucharest; (d) West University in Timisoara, Timisoara, Romania luj Napoca; (c) University Politehnica Bucharest, Bucharest; (d) West Un Cluj Napoca; (c) University Politehnica Bucharest, Bucharest; (d) West University in Timisoara, Timisoara, Romania 7 Departamento de Física, Universidad de Buenos Aires, Buenos Aires, Ar 28 Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom 28 Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom
29 29 Department of Physics, Carleton University, Ottawa, ON, Canada 30 CERN, Geneva, Switzerland ATLAS Collaboration Yang 174, U.K. Yang 83,
Y. Yang 110, S. Yanush 92, L. Yao 33a, W-M. Yao 15, Y. Yasu 65, E. Yatsenko 42, K.H. Yau Wong 21, J. Ye 40,
S. Ye 25, I. Yeletskikh 64, A.L. Yen 57, E. Yildirim 42, M. Yilmaz 4b, R. Yoosoofmiya 124, K. Yorita 172,
R. Yoshida 6, K. Yoshihara 156, C. Young 144, C.J.S. Young 30, S. Youssef 22, D.R. Yu 15, J. Yu 8, J.M. Yu 88,
J. Yu 113, L. Yuan 66, A. Yurkewicz 107, I. Yusuff 28,an, B. Zabinski 39, R. Zaidan 62, A.M. Zaitsev 129,aa,
A. Zaman 149, S. Zambito 23, L. Zanello 133a,133b, D. Zanzi 87, C. Zeitnitz 176, M. Zeman 127, A. Zemla 38a,
K. Zengel 23, O. Zenin 129, T. Ženiš 145a, D. Zerwas 116, G. Zevi della Porta 57, D. Zhang 88, F. Zhang 174,
H. Zhang 89, J. Zhang 6, L. Zhang 152, X. Zhang 33d, Z. Zhang 116, Z. Zhao 33b, A. Zhemchugov 64,
J. Zhong 119, B. Zhou 88, L. Zhou 35, N. Zhou 164, C.G. Zhu 33d, H. Zhu 33a, J. Zhu 88, Y. Zhu 33b, X. Zhuang 33a
K. Zhukov 95, A. Zibell 175, D. Zieminska 60, N.I. Zimine 64, C. Zimmermann 82, R. Zimmermann 21,
S. Zimmermann 21, S. Zimmermann 48, Z. Zinonos 54, M. Ziolkowski 142, G. Zobernig 174, A. Zoccoli 20a,20b,
M. zur Nedden 16, G. Zurzolo 103a,103b, V. Zutshi 107, L. Zwalinski 30 S. Zimmermann 21, S. Zimmermann 48, Z. Zinonos 54, M. Ziolkowski 142, G. Zobernig 174, A. Zoccoli 20a,20b,
M. zur Nedden 16, G. Zurzolo 103a,103b, V. Zutshi 107, L. ATLAS Collaboration Zwalinski 30 1 Department of Physics, University of Adelaide, Adelaide, Australia 1 Department of Physics, University of Adelaide, Adelaide, Australia 2 Physics Department, SUNY Albany, Albany, NY, United States 3 Department of Physics, University of Alberta, Edmonton, AB, Canada ,
,
,
versity, Ankara; (b) Department of Physics, Gazi University, Ankara; (c) Division of Physics, TOBB University of Economics and Technology, Ankara
ara, Turkey p
f
y
,
y f
,
,
,
4 (a) Department of Physics, Ankara University, Ankara; (b) Department of Physics, Gazi University, Ankara; (c) Division of Physics, TOBB University of Economics and Technology, Ankara;
(d) Turkish Atomic Energy Authority, Ankara, Turkey p
f
y
,
y f
,
,
,
4 (a) Department of Physics, Ankara University, Ankara; (b) Department of Physics, Gazi University, Ankara; (c) Division of Physics, TOBB University of Economics and Technology, Ankara;
(d) Turkish Atomic Energy Authority, Ankara, Turkey 4 (a) Department of Physics, Ankara University, Ankara; (b) Department of Physics, Gazi University, Ankara 4 (a) Department of Physics, Ankara University, Ankara; (b) Department of Physics, Gazi University, Ankara; (c) Division of Physics, T
(d) Turkish Atomic Energy Authority, Ankara, Turkey 4 (a) Department of Physics, Ankara University, Ankara; (b) Departmen (d) Turkish Atomic Energy Authority, Ankara, Turkey (d) Turkish Atomic Energy Authority, Ankara, Turkey 5 LAPP, CNRS/IN2P3 and Université de Savoie, Annecy-le-Vieux, France 5 LAPP, CNRS/IN2P3 and Université de Savoie, Annec 5 LAPP, CNRS/IN2P3 and Université de Savoie, Annecy-le-Vieux, France 6 High Energy Physics Division, Argonne National Laboratory, Argonne, IL, United State 6 High Energy Physics Division, Argonne National Laboratory, Argonne, IL, United States 7 Department of Physics, University of Arizona, Tucson, AZ, United Stat 7 Department of Physics, University of Arizona, Tucson, AZ, United States p
f
y
y f
8 Department of Physics, The University of Texas at Arlington, Arlington, TX, United States 8 Department of Physics, The University of Texas at Arlington, Arlington, TX, United States 8 Department of Physics, The University of Texas at Arlington, 9 Physics Department, University of Athens, Athens, Greece 10 Physics Department, National Technical University of Athens, Zograf 10 Physics Department, National Technical University of Athens, Zografou, Greece 11 Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan 11 Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan f
y
j
y f
j
12 Institut de Física d’Altes Energies and Departament de Física de la Universitat Autònoma de Barcelona, Barcelona, Spain
b 12 Institut de Física d’Altes Energies and Departament de Física de la Universitat Autònoma de Barcelona, B 12 Institut de Física d’Altes Energies and Departament de Física de la U g
p
13 (a) Institute of Physics, University of Belgrade, Belgrade; (b) Vinca Institute of Nuclear Sciences, U 3 (a) Institute of Physics, University of Belgrade, Belgrade; (b) Vinca Insti 13 (a) Institute of Physics, University of Belgrade, Belgrade; (b) Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia 14 Department for Physics and Technology, University of Bergen, Bergen, Norway 14 Department for Physics and Technology, University of Bergen, Bergen, Norway 15 Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States 15 Physics Division, Lawrence Berkeley National Laboratory and U 15 Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States 16 Department of Physics, Humboldt University, Berlin, Germany 16 Department of Physics, Humboldt University, Berlin, Germany 16 Department of Physics, Humboldt University, Berlin, Germany
17 p
f
y
y
y
17 Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics, University of Bern, Bern, Switzerland
18 17 Albert Einstein Center for Fundamental Physics and Laboratory 17 Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics, Univ 19 (a) Department of Physics, Bogazici University, Istanbul; (b) Department of Physics, Dogus University, Istanbul; (c) Department of Physics Engineering, Gaziantep University, Gaziantep,
Turkey 19 (a) Department of Physics, Bogazici University, Istanbul; (b) Department of Physics, Dogus University, Istanbul; (c) Department of Physics E
Turkey 19 (a) Department of Physics, Bogazici University, Istanbul; (b) Department of Physics, Dogus University, Istanbul; (c) Department of Physics Engineering, Gaziantep University, Gaziantep,
Turkey ATLAS Collaboration Yu 8, J.M. Yu 88,
J. Yu 113, L. Yuan 66, A. Yurkewicz 107, I. Yusuff 28,an, B. Zabinski 39, R. Zaidan 62, A.M. Zaitsev 129,aa,
A. Zaman 149, S. Zambito 23, L. Zanello 133a,133b, D. Zanzi 87, C. Zeitnitz 176, M. Zeman 127, A. Zemla 38a,
K. Zengel 23, O. Zenin 129, T. Ženiš 145a, D. Zerwas 116, G. Zevi della Porta 57, D. Zhang 88, F. Zhang 174,
H. Zhang 89, J. Zhang 6, L. Zhang 152, X. Zhang 33d, Z. Zhang 116, Z. Zhao 33b, A. Zhemchugov 64,
J. Zhong 119, B. Zhou 88, L. Zhou 35, N. Zhou 164, C.G. Zhu 33d, H. Zhu 33a, J. Zhu 88, Y. Zhu 33b, X. Zhuang 33a,
K. Zhukov 95, A. Zibell 175, D. Zieminska 60, N.I. Zimine 64, C. Zimmermann 82, R. Zimmermann 21,
S. Zimmermann 21, S. Zimmermann 48, Z. Zinonos 54, M. Ziolkowski 142, G. Zobernig 174, A. Zoccoli 20a,20b,
M. zur Nedden 16, G. Zurzolo 103a,103b, V. Zutshi 107, L. Zwalinski 30 C. Weiser 48, H. Weits 106, P.S. Wells 30, T. Wenaus 25, D. Wendland 16, Z. Weng 152,ae, T. Wengler 30,
S. Wenig 30, N. Wermes 21, M. Werner 48, P. Werner 30, M. Wessels 58a, J. Wetter 162, K. Whalen 29,
A. White 8, M.J. White 1, R. White 32b, S. White 123a,123b, D. Whiteson 164, D. Wicke 176, F.J. Wickens 130,
W. Wiedenmann 174, M. Wielers 130, P. Wienemann 21, C. Wiglesworth 36, L.A.M. Wiik-Fuchs 21,
P.A. Wijeratne 77, A. Wildauer 100, M.A. Wildt 42,ak, H.G. Wilkens 30, J.Z. Will 99, H.H. Williams 121,
S. Williams 28, C. Willis 89, S. Willocq 85, A. Wilson 88, J.A. Wilson 18, I. Wingerter-Seez 5,
F. Winklmeier 115, B.T. Winter 21, M. Wittgen 144, T. Wittig 43, J. Wittkowski 99, S.J. Wollstadt 82,
M.W. Wolter 39, H. Wolters 125a,125c, B.K. Wosiek 39, J. Wotschack 30, M.J. Woudstra 83, K.W. Wozniak 39,
M. Wright 53, M. Wu 55, S.L. Wu 174, X. Wu 49, Y. Wu 88, E. Wulf 35, T.R. Wyatt 83, B.M. Wynne 46,
S. Xella 36, M. Xiao 137, D. Xu 33a, L. Xu 33b,al, B. Yabsley 151, S. Yacoob 146b,am, R. Yakabe 66, M. Yamada 65,
H. Yamaguchi 156, Y. Yamaguchi 117, A. Yamamoto 65, K. Yamamoto 63, S. Yamamoto 156, T. Yamamura 156,
T. Yamanaka 156, K. Yamauchi 102, Y. Yamazaki 66, Z. Yan 22, H. Yang 33e, H. 30 CERN, Geneva, Switzerland Andronikashvili Institute of Physics, Iv. 30 CERN, Geneva, Switzerland Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk, Belarus 91 B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, M 92 National Scientific and Educational Centre for Particle and High Energy Physics, Minsk, Belarus 92 National Scientific and Educational Centre for Particle and High Energy Physics, Minsk, Belarus 93 Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, United States Department of Physics, Massachusetts Institute of Technology, Cambridg 94 Group of Particle Physics, University of Montreal, Montreal, QC, Canad 94 Group of Particle Physics, University of Montreal, Montreal, QC, Cana 95 P.N. Lebedev Institute of Physics, Academy of Sciences, Moscow, Russia 96 Institute for Theoretical and Experimental Physics (ITEP), Moscow, Russia f
p
y
(
)
97 National Research Nuclear University MEPhI, Moscow, Russia 97 National Research Nuclear University MEPhI, Moscow, Russia 97 National Research Nuclear University MEPhI, Moscow, Russia 98 D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, Moscow, Russia 98 D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, Moscow 98 D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov M 100 Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), München, Germany 100 Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), München, G 100 Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), Münc 101 Nagasaki Institute of Applied Science, Nagasaki, Japan 101 Nagasaki Institute of Applied Science, Nagasaki, Japan f
y
g y
y
g y
J p
103 (a) INFN Sezione di Napoli; (b) Dipartimento di Fisica, Università di Napoli, Napoli, Italy f
y
g y
y
g y
J p
103 (a) INFN Sezione di Napoli; (b) Dipartimento di Fisica, Università di Napoli, Napoli, Italy 104 Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM, United States 106 Nikhef National Institute for Subatomic Physics and University of Amsterdam, Amsterdam, Netherla 106 Nikhef National Institute for Subatomic Physics and University of Amsterdam, Amsterdam, Netherlands 107 Department of Physics, Northern Illinois University, DeKalb, IL, United States 107 Department of Physics, Northern Illinois University, DeKalb, IL, United States 108 Budker Institute of Nuclear Physics, SB RAS, Novosibirsk, Russia 108 Budker Institute of Nuclear Physics, SB RAS, Novosibirsk, Russia 109 Department of Physics, New York University, New York, NY, United States 109 Department of Physics, New York University, New York, NY, United States 110 Ohio State University, Columbus, OH, United States 111 Faculty of Science, Okayama University, Okayama, Japan y f
y
y
y
J p
112 Homer L. 30 CERN, Geneva, Switzerland 31 Enrico Fermi Institute, University of Chicago, Chicago, IL, United States ,
y f
g ,
g ,
,
32 (a) Departamento de Física, Pontificia Universidad Católica de Chile, Santiago; (b) Departamento de Física, Universidad Técnica Federico Santa María, Valparaíso, Chile
33 (a) Institute of High Energy Physics, Chinese Academy of Sciences, Beijing; (b) Department of Modern Physics, University of Science and Technology of China, Anhui; (c) Department of
Physics, Nanjing University, Jiangsu; (d) School of Physics, Shandong University, Shandong; (e) Physics Department, Shanghai Jiao Tong University, Shanghai, China
34 Laboratoire de Physique Corpusculaire, Clermont Université and Université Blaise Pascal and CNRS/IN2P3, Clermont-Ferrand, France
35 32 (a) Departamento de Física, Pontificia Universidad Católica de Chile, Santiago; (b) Departamento de Física, Universidad Técnica Federico Santa María, Valparaíso, Chile
33 (a) Institute of High Energy Physics, Chinese Academy of Sciences, Beijing; (b) Department of Modern Physics, University of Science and Technology of China, Anhui; (c) Department of
d 32 (a) Departamento de Física, Pontificia Universidad Católica de Chile, Santiago; (b) Departamento de Física, Universidad Técnica Federico Santa María, Valparaíso, Chile
33 ( )
(b)
( ) 2 (a) Departamento de Física, Pontificia Universidad Católica de Chile, Sa p
,
fi
,
g ;
p
,
33 (a) Institute of High Energy Physics, Chinese Academy of Sciences, Beijing; (b) Department of Modern Physics, 33 (a) Institute of High Energy Physics, Chinese Academy of Sciences, Beijing; (b) Department of Modern Physics, University of Science and Technology of China, Anhui; (c) Department of
Physics, Nanjing University, Jiangsu; (d) School of Physics, Shandong University, Shandong; (e) Physics Department, Shanghai Jiao Tong University, Shanghai, China
34 Laboratoire de Physique Corpusculaire, Clermont Université and Université Blaise Pascal and CNRS/IN2P3, Clermont-Ferrand, France
35 hysics, Nanjing University, Jiangsu; (d) School of Physics, Shandong Univ Physics, Nanjing University, Jiangsu; (d) School of Physics, Shandong University, Shandong; (e) Physics Departme y
j
g
y J
g
f
y
g
y
g
y
p
g
J
g
y
g
34 Laboratoire de Physique Corpusculaire, Clermont Université and Université Blaise Pascal and CNRS/IN2P3, Clermont-Ferrand, France
35 34 Laboratoire de Physique Corpusculaire, Clermont Université and Université Blaise Pascal and CNRS/IN2P3, Clermont-Fe
35 34 Laboratoire de Physique Corpusculaire, Clermont Université and Uni 35 Nevis Laboratory, Columbia University, Irvington, NY, United States 36 Niels Bohr Institute, University of Copenhagen, Kobenhavn, Denmark 37 (a) INFN Gruppo Collegato di Cosenza, Laboratori Nazionali di Frascati; (b) Dipartimento di Fisica, Università della Calabria, Rende, Italy 37 (a) INFN Gruppo Collegato di Cosenza, Laboratori Nazionali di Frascati; (b) Dipartimento di Fisica, Università della Calabria, Rende 37 (a) INFN Gruppo Collegato di Cosenza, Laboratori Nazionali di Frascati; (b) Dipartimento di Fis 7 (a) INFN Gruppo Collegato di Cosenza, Laboratori Nazionali di Frascati ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 215 nology, Faculty of Physics and Applied Computer Science, Krakow; (b) Marian Smoluchowski Institute of Physics, Jagiellonian University, Krakow, 38 (a) AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Krakow; (b) Marian Smoluchowski Institute of Physics, Jagiellonian University, Krakow,
Poland Poland
39 The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Krakow, Poland
40 39 The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Krakow, Po y
f
y
y f
40 Physics Department, Southern Methodist University, Dallas, TX, United States 40 Physics Department, Southern Methodist University, Dallas, TX, United States y
p
y
41 Physics Department, University of Texas at Dallas, Richardson, TX, Un y
p
y
Physics Department, University of Texas at Dallas, Richardson, TX, Unite 42 DESY, Hamburg and Zeuthen, Germany 43 Institut für Experimentelle Physik IV, Technische Universität Dortmund, Dortmund, Germany 43 Institut für Experimentelle Physik IV, Technische Universität Dortmund, Dortmund, Germany 43 Institut für Experimentelle Physik IV, Technische Universität Dortm 44 Institut für Kern- und Teilchenphysik, Technische Universität Dresd 45 Department of Physics, Duke University, Durham, NC, United States 45 Department of Physics, Duke University, Durham, NC, United States 46 SUPA – School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom 46 SUPA – School of Physics and Astronomy, University of Edinburgh, E 46 SUPA – School of Physics and Astronomy, University of Edinburgh, Edinburgh, United King 47 INFN Laboratori Nazionali di Frascati, Frascati, Italy 48 Fakultät für Mathematik und Physik, Albert-Ludwigs 48 Fakultät für Mathematik und Physik, Albert-Ludwigs-Universität, Freiburg, Germany 49 Section de Physique, Université de Genève, Geneva, Switzerland 50 (a) INFN Sezione di Genova; (b) Dipartimento di Fisica, Università 51 (a) E. 30 CERN, Geneva, Switzerland Javakhishvili Tbilisi State University, Tbilisi; (b) f
y
,
J
y,
;
g
gy
y
,
y,
,
g
52 II Physikalisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany
53 ikalisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany 53 SUPA – School of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdo 54 II Physikalisches Institut, Georg-August-Universität, Göttingen, Germany 55 Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS/IN2P3, Grenoble, France Laboratoire de Physique Subatomique et de Cosmologie, Université Gren y q
q
g
56 Department of Physics, Hampton University, Hampton, VA, United States 57 Laboratory for Particle Physics and Cosmology, Harvard University, Cambridge, MA, United States
b 57 Laboratory for Particle Physics and Cosmology, Harvard University, Cambridge, MA, United States Laboratory for Particle Physics and Cosmology, Harvard University, Cam hysics and Cosmology, Harvard University, Cambridge, MA, United States
Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg; (b) Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg; (c) ZITI Institut für
ht K
l
U i
ität H id lb
M
h i
G 58 (a) Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg; (b) Physikalisch 58 (a) Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg; (b) Physikalisches Institut, Ruprecht-Karls-Universität Hei 58 (a) Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg; (b) Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg; (c) ZITI Institut für 58 (a) Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg; (b) Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg; (c) ZITI Institut für technische Informatik, Ruprecht-Karls-Universität Heidelberg, Mannheim, Germany technische Informatik, Ruprecht-Karls-Universität Heidelberg, Mannheim, Germany 59 Faculty of Applied Information Science, Hiroshima Institute of Technology, Hiroshima, Japan 59 Faculty of Applied Information Science, Hiroshima Institute of Technology, Hiros 60 Department of Physics, Indiana University, Bloomington, IN, United St 60 Department of Physics, Indiana University, Bloomington, IN, United States p
f
y
y
g
61 Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität, Innsbruck, Austria Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität, In 61 Institut für Astro- und Teilchenphysik, Leopold-Fr 61 Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität, Innsbruck, Austr 62 University of Iowa, Iowa City, IA, United States 63 Department of Physics and Astronomy, Iowa State University, Ame 63 Department of Physics and Astronomy, Iowa State University, Ames, IA, United State 64 Joint Institute for Nuclear Research, JINR Dubna, Dubna, Russia 64 Joint Institute for Nuclear Research, JINR Dubna, Dubna, Russia 65 KEK, High Energy Accelerator Research Organization, Tsukuba, Japan 65 KEK, High Energy Accelerator Research Organization, Tsukuba, J 66 Graduate School of Science, Kobe University, Kobe, J 67 Faculty of Science, Kyoto University, Kyoto, Japan 68 Kyoto University of Education, Kyoto, Japan y
y f
y
J p
69 Department of Physics, Kyushu University, Fukuoka, Japan 69 Department of Physics, Kyushu University, Fukuoka, Japan 70 Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La Plata, Argentina 70 Instituto de Física La Plata, Universidad Nacional de La Plata 70 Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La Plata, Argentina
71 71 Physics Department, Lancaster University, Lancaster, United Kingdom y
p
y
g
72 (a) INFN Sezione di Lecce; (b) Dipartimento di Matematica e Fisica, Università del Salento, Lecce, Italy 72 (a) INFN Sezione di Lecce; (b) Dipartimento di Matematica e Fisica, Università del Salento, Lecce, Ita 72 (a) INFN Sezione di Lecce; (b) Dipartimento di Matematica e Fisica, Un 73 Oliver Lodge Laboratory, University of Liverpool, Liverpool, United Kingdom 73 Oliver Lodge Laboratory, University of Liverpool, Liverpool, United Kingdom 74 Department of Physics, Jožef Stefan Institute and University of Ljublja 75 School of Physics and Astronomy, Queen Mary University of London, London, United Kingdo 75 School of Physics and Astronomy, Queen Mary University of London, London, United Kingdom f
y
y
y
y f
g
76 Department of Physics, Royal Holloway University of London, Surrey, United Kingdom 76 Department of Physics, Royal Holloway University of London, Surrey, United Kingdom 77 Department of Physics and Astronomy, University C 78 Louisiana Tech University, Ruston, LA, United States 79 Laboratoire de Physique Nucléaire et de Hautes Energies, UPMC and Université Paris-Diderot and CNRS/IN2P3, Paris, France
80 79 Laboratoire de Physique Nucléaire et de Hautes Energies, UPMC and Université Paris- 80 Fysiska institutionen, Lunds universitet, Lund, Sweden y
81 Departamento de Fisica Teorica C-15, Universidad Autonoma de Madrid, Madrid, Spain
82 81 Departamento de Fisica Teorica C-15, Universidad Autonoma de Madrid, Madrid, Spain 81 Departamento de Fisica Teorica C-15, Universidad Aut 82 Institut für Physik, Universität Mainz, Mainz, German 83 School of Physics and Astronomy, University of Manchester, Manch 84 CPPM, Aix-Marseille Université and CNRS/IN2P3, Marseille, France 84 CPPM, Aix-Marseille Université and CNRS/IN2P3, Marseille, France 85 Department of Physics, University of Massachusetts, Amherst, MA, United Sta 85 Department of Physics, University of Massachusetts, Amherst, MA 86 Department of Physics, McGill University, Montreal, QC, Canada 87 School of Physics, University of Melbourne, Victoria, Australia 87 School of Physics, University of Melbourne, Victoria, Australia 88 Department of Physics, The University of Michigan, Ann Arbor, MI, United Stat 88 Department of Physics, The University of Michigan, Ann Arbor, 89 Department of Physics and Astronomy, Michigan State University, East Lansing, MI, United S 89 Department of Physics and Astronomy, Michigan State University, East Lansing, MI, United States p
f
y
y
g
y
g
90 (a) INFN Sezione di Milano; (b) Dipartimento di Fisica, Università di Milano, Milano, Italy 90 (a) INFN Sezione di Milano; (b) Dipartimento di Fisica, Università di Milano, Milano, Italy p
y
91 B.I. ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 Fermi, Università di Pisa, Pisa, Italy p
y
124 Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA, United St 124 Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA, United States Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA, United States
125 (a) Laboratorio de Instrumentacao e Fisica Experimental de Particulas – LIP, Lisboa; (b) Faculd p
f
y
y,
y f
g ,
g ,
,
125 (a) Laboratorio de Instrumentacao e Fisica Experimental de Particulas – LIP, Lisboa; (b) Faculdade de Ciências, Universidade de Lisboa, Lisboa; (c) Department of Physics, University of
Coimbra, Coimbra; (d) Centro de Física Nuclear da Universidade de Lisboa, Lisboa; (e) Departamento de Fisica, Universidade do Minho, Braga; (f) Departamento de Fisica Teorica y del
Cosmos and CAFPE, Universidad de Granada, Granada (Spain); (g) Dep Fisica and CEFITEC of Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal
126 I
tit t
f Ph
i
A
d
f S i
f th C
h R
bli
P
h
C
h R
bli Laboratorio de Instrumentacao e Fisica Experimental de Particulas – LIP Laboratorio de Instrumentacao e Fisica Experimental de Particulas LIP, Lisboa;
Faculdade de Ciências, Universidade de Lisboa, Lisb
Coimbra, Coimbra; (d) Centro de Física Nuclear da Universidade de Lisboa, Lisboa; (e) Departamento de Fisica, Universidade do Minho, Braga;
( ) p
Coimbra, Coimbra; (d) Centro de Física Nuclear da Universidade de Lisboa, Lisboa; (e) Departamento de Fisica, Universidade do Minh
( ) bra, Coimbra; (d) Centro de Física Nuclear da Universidade de Lisboa, Lisb Coimbra, Coimbra; (d) Centro de Física Nuclear da Universidade de Lisboa, Lisboa; (e) Departamento de ,
;
,
;
p
,
,
g ;
p
y
Cosmos and CAFPE, Universidad de Granada, Granada (Spain); (g) Dep Fisica and CEFITEC of Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal
126 p
g
p
y
Cosmos and CAFPE, Universidad de Granada, Granada (Spain); (g) Dep Fisica and CEFITEC of Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal Cosmos and CAFPE, Universidad de Granada, Granada (Spain); (g) Dep Fisica and CEFITEC of Faculdade d Cosmos and CAFPE, Universidad de Granada, Granada (Spain); (g) Dep 126 Institute of Physics, Academy of Sciences of the Czech Republic, Praha, Czech Republic 126 Institute of Physics, Academy of Sciences of the Czech Republic, 127 Czech Technical University in Prague, Praha, Czech Republic 128 Faculty of Mathematics and Physics, Charles University in Prague, P y f
y
y
g
129 State Research Center Institute for High Energy Physics, Protvino, Russia 130 Particle Physics Department, Rutherford Appleton Laboratory, Didcot, United Kingdom 130 Particle Physics Department, Rutherford Appleton Laboratory, Didcot, United Kingdom 130 Particle Physics Department, Rutherford Appleton Laboratory, Di y
p
,
f
pp
y,
,
131 Physics Department, University of Regina, Regina, SK, Canada 131 Physics Department, University of Regina, Regina, SK, Canada 132 Ritsumeikan University, Kusatsu, Shiga, Japan 133 (a) INFN Sezione di Roma; (b) Dipartimento di Fisica, Sapienza Università di Roma, Roma, Italy 133 (a) INFN Sezione di Roma; (b) Dipartimento di F 133 (a) INFN Sezione di Roma; (b) Dipartimento di Fisica, Sapienza Univ 133 (a) INFN Sezione di Roma; (b) Dipartimento di Fisica, Sapienza Università di Roma, Roma, Italy 134 (a) INFN Sezione di Roma Tor Vergata; (b) Dipartimento di Fisica, Università di Roma 134 (a) INFN Sezione di Roma Tor Vergata; (b) Dipartimento di Fisica, Università di Roma 134 (a) INFN Sezione di Roma Tor Vergata; (b) Dipartimento di Fisica, Università di Roma Tor Vergata, Roma, Italy 134 (a) INFN Sezione di Roma Tor Vergata; (b) Dipartimento di Fisica, Università di Roma Tor Vergata, Roma, Italy 135 (a) INFN Sezione di Roma Tre; (b) Dipartimento di Matematica e Fisica, Università Roma Tre, Roma, Italy 135 (a) INFN Sezione di Roma Tre; (b) Dipartimento di Matematica e Fisica, Università Roma Tre, Roma, Italy p
y
136 (a) Faculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies – Université Hassan II, Casablanca; (b) Centre National de l’Energie des Sciences Techniques
Nucleaires, Rabat; (c) Faculté des Sciences Semlalia, Université Cadi Ayyad, LPHEA – Marrakech; (d) Faculté des Sciences, Université Mohamed Premier and LPTPM, Oujda; (e) Faculté des
sciences Université Mohammed V – Agdal Rabat Morocco 136 (a) Faculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies – Université Hassan II, Casablanca; (b) Centre Na 136 (a) Faculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies – Université Hassa Faculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies Université Hassan II, Casablanca;
Centre National de l Energie des Sciences Techniques
Nucleaires, Rabat; (c) Faculté des Sciences Semlalia, Université Cadi Ayyad, LPHEA – Marrakech; (d) Faculté des Sciences, Université Mohamed Premier and LPTPM, Oujda; (e) Faculté des Nucleaires, Rabat; (c) Faculté des Sciences Semlalia, Universi Nucleaires, Rabat; (c) Faculté des Sciences Semlalia, Université Cadi Ayyad, LPHEA – Marrakech; (d) Faculté des Sciences, Université Mohamed Premier and LPTPM, Oujda sciences, Université Mohammed V – Agdal, Rabat, Morocco ,
g
,
,
137 DSM/IRFU (Institut de Recherches sur les Lois Fondamentales de l’Univers), CEA Saclay (Commissariat à l’Energie Atomique et aux Energies Alternatives), Gif-sur-Yvette, France
138 Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz, CA, United States g
es sur les Lois Fondamentales de l’Univers), CEA Saclay (Commissariat à l’Energie Atomique et aux Energies Alternatives), Gif-sur-Yvette, France
h
i
i
i
f
lif
i
i
d 137 DSM/IRFU (Institut de Recherches sur les Lois Fondamentales d 137 DSM/IRFU (Institut de Recherches sur les Lois Fondamentales de l’Univers), CEA Saclay (Commissariat à l’Energie Atomique et aux Energie
138 137 DSM/IRFU (Institut de Recherches sur les Lois Fondamentales de l’Univers), CEA Saclay (Commissariat à l’En 138 Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz, CA, United States anta Cruz Institute for Particle Physics, University of California Santa Cruz 139 Department of Physics, University of Washington, Seattle, WA, United States 139 Department of Physics, University of Washington, Seattle, WA, United States 140 Department of Physics and Astronomy, University of Sheffield, Sheffield, United Kingdom
141 140 Department of Physics and Astronomy, University of Sheffiel 141 Department of Physics, Shinshu University, Nagano, Japan 142 Fachbereich Physik, Universität Siegen, Siegen, Germany 143 Department of Physics, Simon Fraser University, Burnaby, BC, Cana p
f
y
y
y
144 SLAC National Accelerator Laboratory, Stanford, CA, United States y
f
145 (a) Faculty of Mathematics, Physics & Informatics, Comenius University, Bratislava; (b) Department of Subnuclear Physics, Institute of Exp
Sciences, Kosice, Slovak Republic 145 (a) Faculty of Mathematics, Physics & Informatics, Comenius University, Bratislava; (b) Department of Subnuclear
Sciences Kosice Slovak Republic 145 (a) Faculty of Mathematics, Physics & Informatics, Comenius Unive y f
,
y
f
,
y,
;
p
f
y
,
f
p
y
f
y f
Sciences, Kosice, Slovak Republic
146 (a) Department of Physics, University of Cape Town, Cape Town; (b) Department of Physics, University of Johannesburg, Johannesburg; (c) School of Physics, University of the
Witwatersrand, Johannesburg, South Africa Sciences, Kosice, Slovak Republic Sciences, Kosice, Slovak Republic
146 (a) Department of Physics, University of Cape Town, Cape Town; (b) Department of Physics, University of Johannesburg, Johannesburg; (c) School of Physics, University of the
Witwatersrand Johannesburg South Africa Sciences,
osice, Slo ak
epublic
146 (a) Department of Physics, University of Cape Town, Cape Town; (b) Department of Physics, University of Johannesburg, Johannesburg; (c) School of Physics, University of the
Witwatersrand Johannesburg South Africa ,
,
p
146 (a) Department of Physics, University of Cape Town, Cape Town; (b) Department of Physics, University of Johannesburg, Johannesburg; (c)
Wi
d J h
b
S
h Af i 146 (a) Department of Physics, University of Cape Town, Cape Town; (b) Department of Physics, 146 (a) Department of Physics, University of Cape To 146 (a) Department of Physics, University of Cape Town, Cape Town; (b) Witwatersrand, Johannesburg, South Africa cs, Stockholm University; (b) The Oskar Klein Centre, Stockholm, Sweden 147 (a) Department of Physics, Stockholm University; (b) The Oskar Klei 148 Physics Department, Royal Institute of Technology, Stockholm, Sweden 148 Physics Department, Royal Institute of Technology, Stockholm, Sweden 149 Departments of Physics & Astronomy and Chemistry, Stony Brook University, Stony Brook, NY, United States 149 Departments of Physics & Astronomy and Chemistry, Stony Brook University, Stony Brook, NY, Un 49 Departments of Physics & Astronomy and Chemistry, Stony Brook Uni 150 Department of Physics and Astronomy, University of Sussex, Brig 151 School of Physics, University of Sydney, Sydney, Australia 152 Institute of Physics, Academia Sinica, Taipei, Taiwan 152 Institute of Physics, Academia Sinica, Taipei, Taiwan 153 Department of Physics, Technion: Israel Institute of Technology, Hai p
f
y
f
gy
f
154 Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel 154 Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel 54 Raymond and Beverly Sackler School of Physics and Astronomy, Tel Av 155 Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece 55 Department of Physics, Aristotle University of Thessaloniki, Thessalon 155 Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece p
f
y
,
y f
,
,
156 International Center for Elementary Particle Physics and Department of Physics, The University of Tokyo, Tokyo, Japan p
f
y
y f
156 International Center for Elementary Particle Physics and Department of Physics, The Univers 56 International Center for Elementary Particle Physics and Department 157 Graduate School of Science and Technology, Tokyo Metropolitan University, Tokyo, Japan
1 8 157 Graduate School of Science and Technology, Tokyo Metropolitan University, Tokyo, Japan 158 Department of Physics, Tokyo Institute of Technology, Tokyo, Japan 159 Department of Physics, University of Toronto, Toronto, ON, Canada p
f
y
y f
160 (a) TRIUMF, Vancouver, BC; (b) Department of Physics and Astronomy, York University, Toronto, ON, Canada 160 (a) TRIUMF, Vancouver, BC; (b) Department of Physics and Astronomy, York University, Toronto, ON, Canada 160 (a) TRIUMF, Vancouver, BC; (b) Department of Physics and Astronom p
f
y
y
161 Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan p
f
y
y
161 Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan 162 Department of Physics and Astronomy, Tufts University, Medford, MA, United States 162 Department of Physics and Astronomy, Tufts University, Medford, MA, United States 163 Centro de Investigaciones, Universidad Antonio Narino, Bogota, Colombia 64 Department of Physics and Astronomy, University of California Irvine, 164 Department of Physics and Astronomy, University of California Irvine, Irvine 164 Department of Physics and Astronomy, University of California Irvine, Irvine, CA, United States
165 (a)
(b)
(c)
à p
f
y
y
y f
f
165 (a) INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine; (b) ICTP, Trieste; (c) Dipartimento di Chimica, Fisica e Ambiente, Università
166 165 (a) INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine; (b) ICTP, Trieste; (c) Dipartimento d 65 (a) INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine; (b) ICTP 166 Department of Physics, University of Illinois, Urbana, IL, United States 67 Department of Physics and Astronomy, University of Uppsala, Uppsala 167 Department of Physics and Astronomy, University of Uppsala, Uppsala, Swe 167 Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden 168 Instituto de Física Corpuscular (IFIC) and Departamento de Física Atómica, Molecular y Nuclear and Departamento de Ingeniería Electrón 168 Instituto de Física Corpuscular (IFIC) and Departamento de Física Atómica, Molecular y Nuclear and Departamen 168 Instituto de Física Corpuscular (IFIC) and Departamento de Física Atómica, Molecul de Barcelona (IMB-CNM), University of Valencia and CSIC, Valencia, Spain de Barcelona (IMB-CNM), University of Valencia and CSIC, Valencia, Spain 69 Department of Physics, University of British Columbia, Vancouver, BC, 169 Department of Physics, University of British Columbia, Vancouver, BC, Canad 170 Department of Physics and Astronomy, University of Victoria, Victoria, BC, Canada
171 170 Department of Physics and Astronomy, University of Victoria, Victoria, BC, Canada 171 Department of Physics, University of Warwick, Coventry, United Kingdom
172 172 Waseda University, Tokyo, Japan 30 CERN, Geneva, Switzerland Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK, United States
113 112 Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK, United Sta 112 Homer L. Dodge Department of Physics and Astronomy, Univ 113 Department of Physics, Oklahoma State University, Stillw 113 Department of Physics, Oklahoma State University, Stillwater, OK, United States 113 Department of Physics, Oklahoma State University, Stillwater, OK, United States p
f
y
y
114 Palacký University, RCPTM, Olomouc, Czech Republic ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 216 115 Center for High Energy Physics, University of Oregon, Eugene, OR, United States 115 Center for High Energy Physics, University of Oregon, Eugene, OR, United States 116 LAL, Université Paris-Sud and CNRS/IN2P3, Orsay, France 117 Graduate School of Science, Osaka University, Osaka, Japan 118 Department of Physics, University of Oslo, Oslo, Norway 119 Department of Physics, Oxford University, Oxford, United Kingdom p
f
y
f
y
f
g
120 (a) INFN Sezione di Pavia; (b) Dipartimento di Fisica, Università di Pavia, Pavia, Italy 120 (a) INFN Sezione di Pavia; (b) Dipartimento di Fisica, Università di Pavia, Pavia, Italy 120 (a) INFN Sezione di Pavia; (b) Dipartimento di Fisica, Università d 121 Department of Physics, University of Pennsylvania, Philadelphia, PA, United States 121 Department of Physics, University of Pennsylvania, Philadelphia, PA, United States 121 Department of Physics, University of Pennsylvania, Phi 122 Petersburg Nuclear Physics Institute, Gatchina, Russia g
y
123 (a) INFN Sezione di Pisa; (b) Dipartimento di Fisica E. Fermi, Università di Pisa, Pisa, Italy g
y
123 (a) INFN Sezione di Pisa; (b) Dipartimento di Fisica E. Fe 123 (a) INFN Sezione di Pisa; (b) Dipartimento di Fisica E. ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 /
y
w Also at Academia Sinica Grid Computing, Institute of Physics, Academia Sinica, Taipei, Taiwan. w Also at Academia Sinica Grid Computing, Institute of Physics, A w Also at Academia Sinica Grid Computing, Institute of Physics, Academia Sinica, Taipei, Taiwan. x Also at Laboratoire de Physique Nucléaire et de Hautes Energies, UPMC and Université Paris-Diderot and CNRS/IN2P3, Paris, Fra x Also at Laboratoire de Physique Nucléaire et de Hautes Energies, UPMC and Université Paris-Did y Also at School of Physical Sciences, National Institute of Science Education and Research, Bhubaneswar, India. y Also at School of Physical Sciences, National Institute of Science Education and Resea y
z Also at Dipartimento di Fisica, Sapienza Università di Roma, Roma, Italy. so at Dipartimento di Fisica, Sapienza Università di Roma, Roma, It z Also at Dipartimento di Fisica, Sapienza Università di Roma, Roma, Italy. aa Also at Moscow Institute of Physics and Technology State University, Dolgoprudny, Russia. aa Also at Moscow Institute of Physics and Technology State University, Dolgo ab Also at Section de Physique, Université de Genève, Geneva, Switzerland. ab Also at Section de Physique, Université de Genève, Geneva, Switzerland. ac Also at International School for Advanced Studies (SISSA), Trieste, Italy. c Also at International School for Advanced Studies (SISSA), Trieste ac Also at International School for Advanced Studies (SISSA), Trieste, Italy. d ad Also at Department of Physics and Astronomy, University of South Carolina, Columbia, SC, United States of America. ad Also at Department of Physics and Astronomy, University of South Carolina, Columbia, SC, Unite ae Also at School of Physics and Engineering, Sun Yat-sen University, Guangzhou, China. ae Also at School of Physics and Engineering, Sun Yat-sen University, Guangzhou, China. ae Also at School of Physics and Engineering, Sun Yat-sen Univers af Also at Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow af Also at Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Physics, M.V. Lomonosov Moscow State University, Moscow, Russia af Also at Faculty of Physics, M.V. Lomonosov Moscow State Univ ag Also at National Research Nuclear University MEPhI, Moscow, Russia. ag Also at National Research Nuclear University MEPhI, Moscow, Russia. ah Also at Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Budapest, Hungary. ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 f Also at Department of Physics, California State University, Fresno, CA, United States of America. f Also at Department of Physics, California State University, Fresno, CA, United States of America. g Also at Tomsk State University, Tomsk, Russia. h Also at CPPM, Aix-Marseille Université and CNRS/IN2P3, Marseille, France. h Also at CPPM, Aix-Marseille Université and CNRS/IN2P3, Marseille, France. h Also at CPPM, Aix-Marseille Université and CNRS/IN2P3 i Also at Università di Napoli Parthenope, Napoli, Italy. i Also at Università di Napoli Parthenope, Napoli, Italy. j Also at Institute of Particle Physics (IPP), Canada. k Also at Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg, Russia. k Also at Department of Physics, St. Petersburg State Polytechn s, St. Petersburg State Polytechnical University, St. Petersburg, Russ k Also at Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg, Russia. l Also at Chinese University of Hong Kong, China. y
g
g
m Also at Department of Financial and Management Engineering, University of the Aegean, Chios, Greece. m Also at Department of Financial and Management Engineering, University of the Aegean, Chios, Gree m Also at Department of Financial and Manageme n Also at Louisiana Tech University, Ruston, LA, United States of America. n Also at Louisiana Tech University, Ruston, LA, United States of America. o Also at Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona, Spa o Also at Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona, Spain. p Also at Department of Physics, The University of Texas at Austin, Austin, TX, United States of America. p Also at Department of Physics, The University of Texas at Austin, Austin, TX, Uni q Also at Institute of Theoretical Physics, Ilia State University, Tbilisi, Georgia. q Also at Institute of Theoretical Physics, Ilia State University, Tbilisi, Georgia. q Also at Institute of Theoretical Physics, Ilia State University, Tb r Also at CERN, Geneva, Switzerland. s Also at Ochadai Academic Production, Ochanomizu University, Tokyo, Japan. s Also at Ochadai Academic Production, Ochanomizu University, Tokyo, Japan. t Also at Manhattan College, New York, NY, United States of Am u Also at Institute of Physics, Academia Sinica, Taipei, Taiwan. u Also at Institute of Physics, Academia Sinica, Taipei, Taiwan v Also at LAL, Université Paris-Sud and CNRS/IN2P3, Orsay, France v Also at LAL, Université Paris-Sud and CNRS/IN2P3, Orsay, France. 172 Waseda University, Tokyo, Japan 173 Department of Particle Physics, The Weizmann Institute of Science, Rehovot, Israel 173 Department of Particle Physics, The Weizmann Institute of Science, Rehovot, Israel artment of Physics, University of Wisconsin, Madison, WI, United States Department of Physics, University of Wisconsin, Madison, WI, United Sta 175 Fakultät für Physik und Astronomie, Julius-Maximilians-Universität, Würzburg, Germany 175 Fakultät für Physik und Astronomie, Julius-Maximilians-Universität, Würzburg, Germany 176 Fachbereich C Physik, Bergische Universität Wuppertal, Wuppertal, Germany 176 Fachbereich C Physik, Bergische Universität Wuppertal, Wuppertal, Germany 177 Department of Physics, Yale University, New Haven, CT, United St 77 Department of Physics, Yale University, New Haven, CT, United States 178 Yerevan Physics Institute, Yerevan, Armenia 178 Yerevan Physics Institute, Yerevan, Armenia Yerevan Physics Institute, Yerevan, Armenia
179 Centre de Calcul de l’Institut National de Physique Nucléaire et de Physique des Particules (IN2P3), Villeurbanne, France y
179 Centre de Calcul de l’Institut National de Physique Nucléaire et de Physique des Particules (IN2P3), Villeurbanne, France 179 Centre de Calcul de l’Institut National de Physique Nucléaire et de Physique des Particules (IN2P3), Villeurbanne, Franc a Also at Department of Physics, King’s College London, London, United Kingdom. a Also at Department of Physics, King’s College London, London, United Kingdom. b Also at Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan. b Also at Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan. c Also at Novosibirsk State University, Novosibirsk, Russia. c Also at Novosibirsk State University, Novosibirsk, Russia. d Also at Particle Physics Department, Rutherford Appleton Laboratory, Didcot, United Kingdom. d Also at Particle Physics Department, Rutherford Appleton Laboratory, Didcot, United Kingdom. e Also at TRIUMF, Vancouver, BC, Canada. 217 ATLAS Collaboration / Physics Letters B 740 (2015) 199–217 ah Also at Institute for Particle and Nuclear Physics, Wigner Resea ah Also at Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, B ai Also at Department of Physics, Oxford University, Oxford, United Kingdom. ai Also at Department of Physics, Oxford University, Oxford, United Kingdom. j Also at Department of Physics, Nanjing University, Jiangsu, China ak Also at Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany. ak Also at Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany. al Also at Department of Physics, The University of Michigan, Ann Arbor, MI, United States of America. al Also at Department of Physics, The University of Michigan, Ann Arbor, MI, United am Also at Discipline of Physics, University of KwaZulu-Natal, Durban, South Africa p
y
,
y
,
,
an Also at University of Malaya Department of Physics Kuala Lumpur Malaysia ∗Deceased.
|
https://openalex.org/W4281656840
|
https://discovery.ucl.ac.uk/id/eprint/10168965/1/fraud-in-online-surveys-evidence-from-a-nonprobability-subpopulation-sample.pdf
|
English
| null |
Fraud in Online Surveys: Evidence from a Nonprobability, Subpopulation Sample
|
Journal of experimental political science
| 2,022
|
cc-by
| 2,766
|
Journal of Experimental Political Science (2023), 10, 148–153
doi:10.1017/XPS.2022.8 SHORT REPORT SHORT REPORT SHORT REPORT This article has earned badges for transparent research practices: Open Data and Open Materials. For
details see the Data Availability Statement.
© The Author(s), 2022. Published by Cambridge University Press on behalf of The Experimental Research Section of the
American Political Science Association. This is an Open Access article, distributed under the terms of the Creative
Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use,
distribution and reproduction, provided the original article is properly cited. Fraud in Online Surveys: Evidence from a
Nonprobability, Subpopulation Sample Andrew M. Bell1,2*
and Thomas Gift3 1Indiana University-Bloomington, Bloomington, IN, USA, 2U.S. Army War College, Carlisle, PA, USA and
3University College London, London, UK
*Corresponding author. Email: bellam@iu.edu 1Indiana University-Bloomington, Bloomington, IN, USA, 2U.S. Army War College, Carlisle, PA, USA and
3University College London, London, UK
*Corresponding author. Email: bellam@iu.edu This article has earned badges for transparent research practices: Open Data and Open Materials. For
details see the Data Availability Statement. https://doi.org/10.1017/XPS.2022.8 Published online by Cambridge University Press 1We withhold the survey firm’s name and its associated sub-vendors due to liability reasons.
2Round 2 was launched after Round 1 was halted due to concerns about data quality. For detailed infor-
mation on the survey, see Appendix (Supplementary Material).
3For text, see Appendix. Army rank structure and saluting protocols are so central to Army service that
they are among the first subjects recruits learn in basic training (Army, 2019).
4Email from former US Army major, April 20, 2021.
5Information such as military rank is so defining of an Army member’s career and identity – akin to a
civilian’s job – that respondents should almost never report these details incorrectly (Bell & Terry, 2021).
6For examples of “non-viable” and “highly improbable” responses, see Appendix. Abstract We hired a well-known market research firm whose surveys have been published in lead-
ing political science journals, including JEPS. Based on a set of rigorous “screeners,” we
detected what appears to be exceedingly high rates of identity falsification: over 81 percent
of respondents seemed to misrepresent their credentials to gain access to the survey and
earn compensation. Similarly high rates of presumptive character falsification were present
in panels from multiple sub-vendors procured by the firm. Moreover, we found additional,
serious irregularities embedded in the data, including evidence of respondents using delib-
erate strategies to detect and circumvent one of our screeners, as well as pervasive, observ-
able patterns reflecting that the survey had been taken repeatedly by a respondent or
collection of respondents. This evidence offers reasons to be concerned about the quality
of online nonprobability, subpopulation samples, and calls for further, systematic research. Growing evidence points to problems with “character misrepresentation” in digital
surveys (Ahler et al. 2021; Chandler and Paolacci 2017; Hydock 2018; Ryan 2020;
Wessling et al. 2017). We present concerning results from a nonprobability online
survey of a specific subpopulation fielded through a well-known, commercial firm. A set of rigorous “screeners” revealed extremely high rates of presumptive fraud:
More than 81 percent of respondents appeared to misrepresent themselves as cur-
rent or former US Army members – our subpopulation of interest – to complete the
survey and earn compensation. Presumed falsification rates were similar across
multiple established sub-vendors, indicating that the problems were not idiosyn-
cratic to a particular panel. Data also indicate the use of deliberate tactics to circum-
vent one of our screeners and repeated participation from a respondent or group of
respondents, further raising suspicions about the data. https://doi.org/10.1017/XPS.2022.8 Published online by Cambridge University Press 149 Journal of Experimental Political Science These irregularities point to the potential for significant identity misrepresenta-
tion rates in online nonprobability, subpopulation surveys – rates that are orders of
magnitude greater than those typically reported in standard online surveys
(Callegaro et al. 2014; Cornesse et al. 2020; Kennedy et al. 2020a; Mullinix
et al. 2016). Although online survey firms can vary markedly in their regulation
of quality control – and all should be assessed for data problems (Kennedy et al. 2016) – risks for exceedingly high levels of fraud could be heightened under the
conditions present in our study. Abstract Our findings call for further, systematic
research into the validity of nonprobability online surveys, particularly those
that sample specific subpopulations. They also underscore the imperative for
researchers to develop clear tools and strategies (prior to statistical analyses
and within preregistration plans) to ensure data integrity based on expert knowl-
edge of research subjects. Survey details We contracted a nationally recognized market research firm,1 whose samples have
formed the basis of numerous, widely-cited political science studies, including
articles published in Journal of Experimental Political Science, American Political
Science Review, and Journal of Politics. The firm, which used multiple sub-vendors,
fielded the survey over two separate rounds in April–May 2021.2 https://doi.org/10.1017/XPS.2022.8 Published online by Cambridge University Press • Total invalid: 81.8 percent • Total invalid: 81.8 percent – 43.3 percent of total respondents failed the Army knowledge question. – 35.5 percent of respondents passed the knowledge screen but gave answers
about Army service that were non-viable under federal law or military
administrative rules. – 3.0 percent of respondents reported information about an Army background
and career that was highly improbable. g
• Total valid: 18.2 percent Notably, the number of invalid responses remained consistent across multiple vendors,
each operating in a different survey round (83.7 in Round 1 and 78.9 in Round 2),
suggesting that the problem was not isolated to a specific panel (Table 1). 7Duplicate IP addresses accounted for 11 of the total responses. These responses are included in the
analysis. Additional irregularities 1. Respondents appeared to employ deliberate tactics to circumvent the knowledge
screener. Evidence. Beginning on April 17 in Round 1, the proportion of respondents who
passed the knowledge question with non-viable demographic and career answers
jumped sharply from 15.4 to 65.9 percent (Table 2). Possible explanations for this
unexpected “break” in the data might include collusion (via the sharing of informa-
tion on an email listserv or crowdsourced website), the retaking of surveys on devi-
ces with unique IP addresses, or the use of survey “bots.” 2. Respondents appeared to use deliberate tactics to detect the knowledge question
as a screener. 2. Respondents appeared to use deliberate tactics to detect the knowledge question
as a screener. Evidence. In Round 1 – where failure to pass the knowledge question terminated the
survey immediately – 49.8 percent passed the knowledge question but provided
non-viable career responses. Conversely, in Round 2 – where we modified the setup
so that failure resulted in termination later in the survey, thereby “hiding” the screener –
the number of non-viable fell to 13.7 percent (Table 1). Conversely, the percentage of
respondents who failed the screen rose from 30.6 percent (Round 1) to 62.7 percent
(Round 2). This suggests that, absent a “hidden” screener, later respondents in
Round 1 may have gleaned information from earlier respondents or survey attempts
to identify the screener and defeat it.7 3. A respondent, or collection of respondents, appeared to take the survey numerous
times. 8For examples, see Appendix. Screening process We employed two screeners to confirm the authenticity of respondents with
self-identified Army experience. First, we asked a “knowledge” question about
the practice of saluting, one of the most essential elements of military protocol.3
The question required knowing both the Army’s rank hierarchy and that enlisted
soldiers salute first. Multiple former Army officers consulted for this study validated
the screen, with one stating: “Anyone who is answering that question incorrectly is
either not reading the question or has not served in the military, let alone the
Army.”4 Second, respondents reported specific information on their Army back-
ground including: highest rank achieved, source of officer commission, deployment
years and locations, and unit type.5 We coded “non-viable” responses as those that
provided information contravening federal law or Army personnel policy. We
coded a small number of responses “highly improbable” based on being contrary
to Army personnel practices or historical evidence, but which could be theoretically
plausible.6 Andrew M. Bell and Thomas Gift 150 Key findings Key findings https://doi.org/10.1017/XPS.2022.8 Published online by Cambridge University Press 7Duplicate IP addresses accounted for 11 of the total responses. These responses are included in the
analysis.
8For examples, see Appendix. Journal of Experimental Political Science 151 Table 1
Summary of response categories
Category
Round 1
Count
Round 1 %
Round 2
Count
Round 2 %
Total Count
Total %
Valid
40
16.3%
34
21.1%
74
18.2%
Failed screen
75
30.6%
101
62.7%
176
43.3%
Passed screen,
non-viable
122
49.8%
22
13.7%
144
35.5%
Passed screen,
improbable
8
3.3%
4
2.5%
12
3.0%
Subtotal
245
100.0%
161
100.0%
406
100.0%
Table 2
Irregularity 1: Increase in “non-viable” responses (Round 1)
Pre-break
Post-break
Category
Count
%
Count
%
Valid
28
35.9%
12
7.2%
Failed screen
37
47.4%
38
22.8%
Passed screen, non-viable
12
15.4%
110
65.9%
Passed screen, improbable
1
1.3%
7
4.2%
Total
78
100.0%
167
100.0% Table 1
Summary of response categories Summary of response categories Table 2 distinct waves of repeating answers across the 3 days of responses – suggests that
such repetition was not coincidental. We also observed obvious repetitive patterns
of survey takers seeming to misrepresent personal demographic information. distinct waves of repeating answers across the 3 days of responses – suggests that
such repetition was not coincidental. We also observed obvious repetitive patterns
of survey takers seeming to misrepresent personal demographic information. https://doi.org/10.1017/XPS.2022.8 Published online by Cambridge University Press 3. A respondent, or collection of respondents, appeared to take the survey numerous
times. 3. A respondent, or collection of respondents, appeared to take the survey numerous
times. Evidence. Categorizing conservatively, we identified – at a minimum – 73 suspi-
cious instances of repeated (and unusual) responses regarding Army background
and deployment experience.8 The sequential clustering of these responses – six https://doi.org/10.1017/XPS.2022.8 Published online by Cambridge University Press Journal of Experimental Political Science Journal of Experimental Political Science Conclusion Ethics Statement. This survey was approved by the Indiana University-Bloomington IRB (Protocol #:
1910663858). The research adheres to APSA’s Principles and Guidance for Human Subjects Research. See Supplemental Appendix for more information. References Ahler, D. J., C. E. Roush and G. Sood. 2021. The micro-task market for lemons: Data quality on amazon’s
mechanical turk. Political Science Research and Methods, 1–20. Army. 2014. Department of the Army Pamphlet 600–3, Commissioned Offcer Professional Development and
Career Management. Washington, DC: Headquarters, Department of the Army. my. 2014. Department of the Army Pamphlet 600–3, Commissioned Offcer Profession
Career Management. Washington, DC: Headquarters, Department of the Army. Army. 2019. U.S. Army Training and Doctrine Command Pamphlet 600-4, The Soldier’s Blue Book, Th
Guide for Initial Entry Training Soldiers. Fort Eustis, VA: Department of the Army. Bell, A. M. and F. Terry. 2021. Combatant Rank and Socialization to Norms of Re- straint: Examining the
Australian and Philippine Armies. International Interactions 47(5): 825–854. Callegaro, M., A. Villar, D. Yeager and J. A. Krosnick. 2014. A Critical Review of Studies Investigating
the Quality of Data Obtained with Online Panels based on Probability and Nonprobability Samples. In Online Panel Research: A Data Quality Perspective, eds. Baker, R., Bethlehem, J., Goritz, A. S.,
Kros-nick, J. A., Callegaro, M. and Lavrakas, P. J. West Sussex, UK: John Wiley & Sons. Chandler, J. J. and G. Paolacci. 2017. Lie for a Dime: When Most Prescreening Responses are Honest but
most Study Participants are Impostors. Social Psychological and Personality Science 8(5): 500–508. Cornesse, C., A. G. Blom, D. Dutwin, J. A. Krosnick, E. D. De Leeuw, S. Legleye, J. Pasek and D. Pennay. 2020. A Review of Conceptual Approaches and Empirical Evidence on Probability and Nonprobability
Sample Survey Research. Journal of Survey Statistics and Methodology 8(1): 4–36. p
y
f
y
gy
Hauser, D. J. and N. Schwarz. 2016. Attentive Turkers: MTurk Participants Perform Better on Online
Attention Checks than do Subject Pool Participants. Behavior Research Methods 48(1): 400–407. Hydock, C. 2018. Assessing and Overcoming Participant Dishonesty in Online Data Collection. Behavior
Research Methods 50: 1563–1567. Kennedy, C., A. Mercer, S. Keeter , N. Hatley, K. McGeeney and A.-j. Gimenez. 2016. Evaluating Online
Nonprobability Surveys. Pew Research May 2, 2016. Kennedy, C., N. Hatley, A. Lau, A. Mercer, S. Keeter, J. Ferno and D. Asare-Marf. 2020a. Assessing the
Risks to Online Polls From Bogus Respondents. Pew Feb. 18, 2020. Kennedy, R., S. Clifford, T. Burleigh, P. D. Waggoner, R. Jewell and N. J. G. Winter. 2020b. The Shape of
and Solutions to the mturk Quality Crisis. Political Science Research and Methods 8. 614–629. Lopez, J. Conclusion We see this analysis as an opportunity for learning. Despite taking precautions to
screen out invalid respondents, we found high rates of presumptive fraud. This rein-
forces that researchers should be especially cautious when employing online surveys
using nonprobability samples of specific subpopulations. Given that only about 7
percent of the US population is military or ex-military (Vespa 2020), our results
are consistent with incentives for fraud increasing as the size of the subpopulation
qualifying to participate in surveys decreases (Chandler and Paolacci 2017). Combined with other techniques, employing a diversity of screeners predicated
on expert understanding of research subjects – including factors like demographics
and content knowledge – can improve the odds of detecting falsified responses. Future research should systematically assess the quality of nonprobability surveys
(Hauser and Schwarz 2016; Lopez and Hillygus 2018; Kennedy et al. 2020b;
Thomas and Clifford 2017). By implementing rigorous screeners on diverse Andrew M. Bell and Thomas Gift 152 populations, replicated across many firms and sub-vendors, this could illuminate
whether our results are endemic to nonprobability surveys that sample specific sub-
populations and what the broader implications are for internal and external validity. populations, replicated across many firms and sub-vendors, this could illuminate
whether our results are endemic to nonprobability surveys that sample specific sub-
populations and what the broader implications are for internal and external validity. Supplementary Material. To view supplementary material for this article, please visit https://doi.org/10. 1017/XPS.2022.8 Data Availability. The data, code, and additional materials required to replicate all analyses in this article
are available at the Journal of Experimental Political Science Dataverse within the Harvard Dataverse
Network, at https://doi.org/10.7910/DVN/Y1FEOX” Data Availability. The data, code, and additional materials required to replicate all analyses in this article
are available at the Journal of Experimental Political Science Dataverse within the Harvard Dataverse
Network, at https://doi.org/10.7910/DVN/Y1FEOX” Acknowledgments. The authors thank Christopher DeSante, Timothy Ryan and Steven Webster, two
anonymous U.S. Army officers, as well as anonymous reviewers for their helpful comments and suggestions. Acknowledgments. The authors thank Christopher DeSante, Timothy Ryan and Steven Webster, two
anonymous U.S. Army officers, as well as anonymous reviewers for their helpful comments and suggestions. Conflicts of Interest. The authors declare no conflicts of interest. Ethics Statement. This survey was approved by the Indiana University-Bloomington IRB (Protocol #:
1910663858). The research adheres to APSA’s Principles and Guidance for Human Subjects Research. See Supplemental Appendix for more information. Ryan, T. J. 2020. Fraudulent Responses on Amazon Mechanical Turk: A Fresh Cautionary Tale. Retrieved
from https://timryan.web.unc.edu/2020/12/22/fraudulent-responses-on-amazon-mechanicalturk-a-fresh-
cautionary-tale/ Cite this article: Bell AM and Gift T (2023). Fraud in Online Surveys: Evidence from a Nonprobability,
Subpopulation Sample. Journal of Experimental Political Science 10, 148–153. https://doi.org/10.1017/
XPS.2022.8 Thomas, K. A. and S. Clifford. 2017. Validity and Mechanical Turk: An Assessment of Exclusion Methods
and Interactive Experiments. Computers in Human Behavior 77(1): 184–197. References and D. S. Hillygus. 2018. Why So Serious?: Survey Trolls and Misinformation. SSRN Electronic
Journal. Retrieved from https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3131087 Mullinix, K. J., T. J. Leeper, J. N. Druckman and J. Freese. 2016. The Generalizability of Survey
Experiments. Journal of Experimental Political Science 2(2): 109–138. https://doi.org/10.1017/XPS.2022.8 Published online by Cambridge University Press Journal of Experimental Political Science 153 Ryan, T. J. 2020. Fraudulent Responses on Amazon Mechanical Turk: A Fresh Cautionary Tale. Retrieved
from https://timryan.web.unc.edu/2020/12/22/fraudulent-responses-on-amazon-mechanicalturk-a-fresh-
cautionary-tale/ Ryan, T. J. 2020. Fraudulent Responses on Amazon Mechanical Turk: A Fresh Cautionary Tale. Retrieved
from https://timryan.web.unc.edu/2020/12/22/fraudulent-responses-on-amazon-mechanicalturk-a-fresh-
cautionary-tale/ y
Thomas, K. A. and S. Clifford. 2017. Validity and Mechanical Turk: An Assessment of Exclusion M
and Interactive Experiments. Computers in Human Behavior 77(1): 184–197. Vespa, J. E. 2020. Those Who Served: America’s Veterans From World War II to the War on Terror. American Community Survey Report, U.S. Census Bureau June 2020. Wessling, K. S., J. Huber and O. Netzer. 2017. Mturk Character Misrepresentation: Assessment and
Solutions. Journal of Consumer Research 44(1): 211–230. Cite this article: Bell AM and Gift T (2023). Fraud in Online Surveys: Evidence from a Nonprobability,
Subpopulation Sample. Journal of Experimental Political Science 10, 148–153. https://doi.org/10.1017/
XPS.2022.8 https://doi.org/10.1017/XPS.2022.8 Published online by Cambridge University Press
|
https://openalex.org/W3007438208
|
https://link.springer.com/content/pdf/10.1007/s00464-020-07420-y.pdf
|
English
| null |
The possibility of endoscopic treatment of cN0 submucosal esophageal cancer: results from a surgical cohort
|
Surgical endoscopy/Surgical endoscopy and other interventional techniques
| 2,020
|
cc-by
| 6,282
|
Abstract Background We analyzed the pathological characteristics and recurrence pattern of cN0 submucosal esophageal cancer
after esophagectomy and conducted risk stratification to determine the feasibility of performing endoscopic resection for
cN0pT1b esophageal squamous cell malignancies. p
p
g
q
g
Methods We retrospectively enrolled 167 patients who underwent right-sided transthoracic esophagectomy and extended
thoracic/abdominal two-field lymphadenectomy. Patients with pathologically confirmed lymph node metastasis or tumor
recurrence constituted the high-risk group for endoscopic submucosal resection, and the remainder were defined as low risk. Factors affecting lymphatic metastasis and long-term recurrence were identified by univariate and multivariate analyses. Results Postoperative pathology showed that five patients (5/167; 3%) had lymph node metastases. Follow-up ranged from
12–60 months, with a median of 29 months. A total of 17 patients (10.2%) had recurrences during follow-up, including three
patients with pathologic nodal metastasis (pN +) found at surgery. Invasion depth, differentiation, and tumor size differed
significantly in high-risk patients. Overall 3-year survival rates were 94.2% (low-risk) and 40.9% (high-risk) (p < 0.01). Twenty-one patients with sm1 cancer, high tumor differentiation, and tumor length < 2 cm had no lymph node metastasis or
lymphovascular invasion, and none of these patients experienced recurrence. Methods We retrospectively enrolled 167 patients who underwent right-sided transthoracic esophagectomy and extended
thoracic/abdominal two-field lymphadenectomy. Patients with pathologically confirmed lymph node metastasis or tumor
recurrence constituted the high-risk group for endoscopic submucosal resection, and the remainder were defined as low risk. fi Conclusions Endoscopic submucosal resection alone may be feasible for patients with small (≤ 2 cm) clinically N0 sub-
mucosal esophageal squamous cell carcinoma with low invasion depth (sm1) and higher differentiation, but prospective
studies are required for confirmation. Other patients require surgical resection with extended two-field thoracic/abdominal
lymphadenectomy. Keywords Esophageal · Squamous cell carcinoma · Endoscopic submucosal resection · Clinical N0 pathologic T1b words Esophageal · Squamous cell carcinoma · Endoscopic submucosal resection · Clinical N0 path Superficial esophageal cancer is defined as esophageal
carcinoma with tumor invasion limited to the submucosa. Because of the wide use of endoscopic screening techniques, approximately 36% of patients with esophageal squamous
cell carcinoma (SCC) are diagnosed with superficial
lesions in Japan [1]. Improving overall treatment efficacy
has become a key in enhancing overall outcomes in patients
with esophageal SCC. Because the rates of lymph node
metastasis with intramucosal (T1a) esophageal carcinomas
are extremely low, endoscopic submucosal resection alone
has become the standard treatment [1–3]. Surgical Endoscopy (2021) 35:593–601
https://doi.org/10.1007/s00464-020-07420-y Surgical Endoscopy (2021) 35:593–601
https://doi.org/10.1007/s00464-020-07420-y Bo Ye1 · Xiaobin Zhang1 · Yuchen Su1 · Shuguang Hao2 · Haohua Teng3 · Xufeng Guo1 · Yu Yang1 · Yifeng Sun1 ·
Teng Mao1 · Zhigang Li1 Received: 9 October 2019 / Accepted: 10 February 2020 / Published online: 18 February 2020
© The Author(s) 2020 1
Department of Thoracic Surgery, Shanghai Chest Hospital,
Shanghai Jiao Tong University, Huaihaixi Road 241,
Shanghai 200030, People’s Republic of China Bo Ye and Xiaobin Zhang have contributed equally to this study. * Zhigang Li
dr_lizhigang@163.com 3
Department of Pathology, Shanghai Chest Hospital, Shanghai
JiaoTong University, Huaihaixi Road 241, Shanghai 200030,
People’s Republic of China 2
Department of Thoracic Surgery, Xinxiang Central
Hospital, Xinxiang 453000, Henan Province,
People’s Republic of China Materials and methods is an alternative treatment for T1b patients unwilling
to undergo radical resection [3]. A recent study by the
Japan Clinical Oncology Group (JCOG0508 study) [9]
of patients with T1b (sm1–2) N0M0 thoracic esophageal
SCC confirmed the efficacy of endoscopic resection
combined with selective chemoradiotherapy, with results
comparable to those following surgery [9, 10]. However,
patient selection in the JCOG0508 study was based on a
main tumor depth of invasion of csm1–2 by endoscopic
ultrasonography or pathological diagnosis from endo-
scopically resected specimens, which do not accurately
reflect the depth of invasion, especially the possibility of
sm3 involvement. Additionally, the sample size was not
large (n = 86; pT1b). Larger numbers of surgical cases
are needed to fully explain which patients are suitable for
non-surgical treatment. is an alternative treatment for T1b patients unwilling
to undergo radical resection [3]. A recent study by the
Japan Clinical Oncology Group (JCOG0508 study) [9]
of patients with T1b (sm1–2) N0M0 thoracic esophageal
SCC confirmed the efficacy of endoscopic resection
combined with selective chemoradiotherapy, with results
comparable to those following surgery [9, 10]. However,
patient selection in the JCOG0508 study was based on a
main tumor depth of invasion of csm1–2 by endoscopic
ultrasonography or pathological diagnosis from endo-
scopically resected specimens, which do not accurately
reflect the depth of invasion, especially the possibility of
sm3 involvement. Additionally, the sample size was not
large (n = 86; pT1b). Larger numbers of surgical cases
are needed to fully explain which patients are suitable for
non-surgical treatment. We retrospectively analyzed data from 2023 consecutive
patients with primary esophageal SCC who were treated
at Shanghai Chest Hospital from January 2014 to Decem-
ber 2017. Of these, 229 (11.32%) patients had pathologi-
cally confirmed esophageal SCC with submucosal invasion
(pT1b). After excluding 62 patients preoperatively diagnosed
with lymph node metastasis (cN1), we analyzed data for 167
patients diagnosed with cN0pT1b esophageal SCC (Fig. 1). All 167 patients underwent R0 resection. Our focus in this
study was patients with stage cN0pT1b esophageal SCC,
therefore, we excluded data for stage cN0cT1b patients. The study protocol was approved by the Shanghai Chest
Hospital ethics committee, which waived the requirement
for informed consent because of the retrospective design. This retrospective study analyzed data for patients
with pathologically confirmed T1b esophageal SCC with
clinical N0 submucosal lesions treated with esophagec-
tomy in our center over a 3-year period. Fig. 1 Flow chart showing the
patient selection process for the
study Abstract In contrast, T1b
esophageal carcinomas with submucosal invasion have a
much higher lymph node metastasis rate of approximately
12–54% [4–7]. Therefore, the standard treatment for submu-
cosal lesions consists of radical resection of the esophageal
cancer plus lymph node dissection. Bo Ye and Xiaobin Zhang have contributed equally to this study. 2
Department of Thoracic Surgery, Xinxiang Central
Hospital, Xinxiang 453000, Henan Province,
People’s Republic of China Surgical treatment of esophageal cancer is traumatic
for patients and associated with high postoperative com-
plication rates [8]. Endoscopic submucosal resection (0121 3456789)
3 594 Surgical Endoscopy (2021) 35:593–601 cN0 diagnostic criteria Patients were diagnosed with cN0 disease if carotid/
abdominal ultrasound, endoscopic ultrasound, contrast-
enhanced thoracoabdominal CT, and other imaging
modalities found no evidence of lymph nodes > 1 cm diam-
eter. Other diagnostic criteria for cN0 disease included
an absence of central liquefaction/necrosis, peripheral
enhancement, or disappearance of the fatty gap near the
lymph nodes. No patients underwent endoscopic ultra-
sound-guided biopsy to confirm cN0 status. Surgical treatment Decisions on appropriate therapy for superficial esopha-
geal SCC were discussed by a multidisciplinary tumor
board. No patients received preoperative induction ther-
apy, and all patients underwent thoracic and abdominal
lymph node dissection, including dissection of the lymph
nodes near bilateral recurrent laryngeal nerves. Materials and methods We compared
the different clinical features of high-risk and low-risk
patients, where high-risk patients were those with surgi-
cal lymph node metastasis or later recurrence, and the
remainder were defined as low-risk patients. The latter
are considered possible endoscopic treatment candidates
who can avoid esophagectomy and extensive lymph node
dissection. All patients underwent thoracic and abdominal lymph
node dissection. We retrospectively reviewed and recorded
patients’ general information, surgical procedures, postop-
erative hospitalization details, follow-up duration, and recur-
rence and survival rates after discharge from the hospital. Preoperative assessment included contrast-enhanced
thoracoabdominal computed tomography (CT), cervi-
cal ultrasound, and upper gastrointestinal endoscopy. All
patients underwent endoscopic ultrasound, and only 53
patients underwent positive emission tomography. e Fig. 1 Flow chart showing the
patient selection process for the
tudy 1 3 Surgical Endoscopy (2021) 35:593–601 595 during each follow-up examination, and we used the Cla-
vien–Dindo system to evaluate complications [11]. Statistical analysis All statistical analyses were performed using SPSS software
(IBM SPSS Statistics, V21, macOS X; IBM Corp., Armonk,
NY). Categorical data were analyzed with the Chi-square
test. For continuous data, we used the independent t test or
Mann–Whitney U test to analyze age, depth of invasion,
and tumor length. We also performed multivariate logistic
regression analysis using a backward stepwise procedure and
adding all of the significant risk factors from the univariate
analysis to identify the significant predictors for the high-
risk group. Survival was defined as the time from the first
postoperative day to the last day of follow-up or death. We
used Kaplan–Meier survival curves to calculate recurrence-
free and overall survival for all patients, and p < 0.05 was
considered statistically significant. Postoperative pathological diagnosis We analyzed data for 167 patients, namely, 131 men (81.4%)
and 36 women (21.6%) with a mean (± standard deviation)
age of 62.9 ± 8.8 years. Of these patients, 22 (13.2%) had
lesions in the upper third, 111 (66.5%) in the middle third,
and 34 (20.4%) in the lower third of the esophagus. Preop-
erative T stages included T1a in 30 patients (18%), T1b in
106 (63.5%), T2 in 31 (18.5%), and T3 in no patients; all
patients were preoperative N stage 0 (N0). Pathological sections for all clinically diagnosed T1b
esophageal SCC samples were retrospectively analyzed
by two senior pathologists. T1b (submucosal invasion)
was defined as invasion into the submucosal layer but not
reaching the muscularis propria. The specific pathologi-
cal characteristics that we analyzed were tumor length,
location, differentiation, and depth of invasion. Depth
of invasion was categorized as: sm1, invasion of the
upper third of the submucosal layer or ≤ 200 μm from the
mucosal muscularis in the specimens resected by endo-
scopic resection; sm2, invasion reaching the middle third
of the submucosal layer; or sm3, invasion reaching the
lower third of the submucosal layer. Other parameters were
lymphovascular invasion, perineural invasion, total num-
ber of lymph nodes dissected, and number and location of
positive lymph nodes. No patients received preoperative induction therapy. All
patients underwent esophageal SCC resection via a right
transthoracic approach, with 151 (90.4%) undergoing McK-
eown (three-incision) esophagectomy and 16 (9.58%) under-
going Ivor–Lewis operations; 136 patients (81.4%) under-
went minimally invasive video-assisted thoracoscopy, and
31 (18.6%) underwent open surgery. Complications of any type occurred in 41.3% (69/167)
of the patients. The percentage of patients experiencing
Clavien–Dindo complications ≥ grade 3 was 12% (20/167). The main complications were anastomotic leak (confirmed
radiographically) in 28 patients (16.7%), respiratory insuffi-
ciency in 10 (6%) (defined as patients requiring reintubation
or a non-invasive ventilator support), and recurrent laryngeal
nerve paralysis (confirmed using laryngoscopy 1-week post-
operatively) in 19 (11.4%) patients (Table 1). We recorded the concordance rate between the two sen-
ior pathologists, and differences in opinion regarding the
pathological diagnosis for any sample were resolved by
discussion among all of the department’s pathologists. Follow‑up The average hospital stay was 18.5 days (range,
7–190 days). No patients died in-hospital or within 90 days
postoperatively (Table 1), and 5 patients with lymph node
metastasis received two cycles of adjuvant chemotherapy. Patients were followed at the out-patient clinic or by tel-
ephone 1, 3, 6 months, and then every 6 months, post-
operatively. Esophagogastroduodenoscopy, and CT of
the thorax, abdomen, and neck were routinely performed Postoperative pathological examination showed submu-
cosal invasion (T1b) in all patients. The numbers of patients 1 3 Surgical Endoscopy (2021) 35:593–601 596 Table 1 Patients’ demographic and clinical characteristics (n = 167)
n number
Variable
n(%)
Age (years) ± standard deviation
62.91 ± 8.80
Sex
Male
131(78.44)
Female
36(21.56)
Tumor location in the esophagus
Lower third
34(20.36)
Middle third
111(66.47)
Upper third
22(13.17)
Tumor length (mm)
20.36 ± 10.18
Surgical approach
McKeown
151(90.42)
Ivor–Lewis
16(9.58)
Minimally invasive esophagectomy
136(81.44)
Open
31(18.56)
Complications
Anastomotic leak
28(16.77)
Respiratory failure
10(5.99)
Recurrent laryngeal nerve paralysis
19(11.38)
In-hospital Stay (days) (mean, range)
18.50(7–190)
Death within 90 days postoperatively
0(0) in the inferior mediastinum/abdomen, and 1 (5.8%) in the
pleural cavity (pleural effusion).f f
Univariate analysis showed that degree of differentiation,
invasion depth, and tumor length differed significantly in the
two groups (p < 0.05 for all comparisons) (Table 2). Multi-
variate analysis showed that degree of differentiation, inva-
sion depth, and tumor length were independently associated
with the likelihood of being in the high-risk group (Table 3). The median postoperative follow-up duration for
all patients was 29 months. The median follow-up was
36.4 months (range, 13.5–51.8 months) in the high-risk
group and 31.2 months (range, 10.4–57.6 months) in the
low-risk group. Overall 3-year survival rates were 94.2%
(low-risk group) and 40.9% (high-risk group) (hazard ratio:
9.418, 95% confidence interval: 3.819–23.222; p < 0.01)
(Fig. 2). Nineteen patients died after 90 days; 10 in the high-risk
group and 9 in the low-risk group. In the high-risk group, 9
patients died of recurrence, and 1 died of abdominal infec-
tion. In the low-risk group, 1 patient died of suicide, 1 of
heart disease, 3 of lung infection, 1 secondary to anasto-
mosis stenosis and malnutrition, and 3 of unknown causes. Follow‑up Regarding the diagnostic thresholds for endoscopic
submucosal resection, a separate analysis showed that 21
patients with sm1 tumors, high tumor differentiation, and
tumor length < 2 cm had no lymph node metastasis or lym-
phovascular invasion, and none experienced recurrence. Of
the remaining 146 patients, 5 (5/146, 3.4%) experienced
lymph node metastasis (p < 0.01), 17 (17/146, 11.6%) expe-
rienced recurrence (p < 0.01), and 10 (10/146, 6.8%) expe-
rienced lymphovascular invasion (Table 4). All of these 146
patients had at least one of the following findings: > sm1
tumors, low tumor differentiation, and tumor length > 2 cm. with sm1, sm2, and sm3 invasion were 96/167 (57.5%),
48/167 (28.7%), and 23/167 (13.8%). The median number of
dissected lymph nodes was 23 (range, 10–44). Postoperative
pathology showed that five patients (5/167, 3%) had lymph
node metastases, which were located at the thoracic paratra-
cheal (n = 3, 60%), paracardiac (n = 1, 20%), and subcarinal
(n = 1, 20%) sites. Of the patients with sm1, sm2, and sm3
invasion, 0, 2/48 (4.2%), and 3/23 (13.04%), respectively,
had lymph node metastases (p < 0.05, for all comparisons). Lymphovascular invasion was detected in 10 patients, but
none had postoperative lymph node metastasis or recurrence. f
The concordance rate between the two senior pathologists
analyzing the tissue samples was 89.5% (205/229 histologi-
cal diagnosis agreements). p
p
y p
The 19 patients (19/167, 11.4%) with pathologically
confirmed lymph node metastasis or tumor recurrence were
classified as the high-risk group, namely, 5 patients with
positive lymph node metastasis and 14 patients with recur-
rent disease, with the remaining 148 patients (148/167,
88.6%) classified as the low-risk group. During follow-
up, 17 patients (17/167, 10.2%) developed recurrence at a
median of 683.5 days, namely, 14/162 (8.6%) in the pN0
group and 3/5 (60%) in the pN+ group. Of the 14 patients
with recurrent tumors in the pN0 group, 12 were classified as
sm2 or sm3, 13 had moderate/low differentiation, and 13 had
a diameter ≥ 2 cm. Of the 17 patients with tumor recurrence
(14 in the pN0 group and 3 in the pN+ group), 9 (52.9%)
had recurrent tumors in the neck/superior mediastinum, 5
(29.4%) in the carina/left and/or right bronchus, 3 (17.6%) Discussion Endoscopic submucosal dissection can
achieve R0 resection of some localized superficial lesions;
however, because of the high rate of lymph node metastasis 1 3 3 Surgical Endoscopy (2021) 35:593–601 597 Values are presented as number, number(percent), or mean ± standard deviation
a Mann–Whitney U test; LND number of lymph nodes dissected, LVI lymphovascular invasion, sm1 inva-
sion of the upper third of the submucosal layer or reaching the submucosal layer > 200 µm from the muscu-
laris, sm2 invasion reaching the middle third of the submucosal layer, sm3 invasion reaching the lower third
of the submucosal layer
Variable
Low-risk group (n = 148)
High-risk group (n = 19)
p valuea
Sex
0.067
Male
113(76.35)
18(94.74%
Female
35(23.65)
1(5.26)
Age
63.02 ± 7.3
62.05 ± 8.52
0.946
Surgical approach
McKeown
135(91.22)
16(84.21)
0.329
Ivor–Lewis
13(8.78)
3(15.79)
Minimally invasive esophagectomy
122(82.43)
14(73.68)
0.356
Open
26(17.57)
5(26.32)
Number of LND
24.48 ± 7.90
23.11 ± 6.60
0.504a
Tumor location in the esophagus
0.904
Upper third
18(12.16)
3(15.79)
Middle third
97(65.54)
12(63.16)
Lower third
33(22.3)
4(21.05)
Differentiation
< 0.001
Well
70(47.3)
2(10.53)
Moderate
41(27.7)
5(26.32)
Poor
37(25)
12(63.16)
Depth of invasion
< 0.001
sm1
93(62.84)
3(15.79)
sm2
43(29.05)
5(26.32)
sm3
12(8.11)
11(57.89)
LVI
10 (6.76)
0
0.243
Tumor length (mm)
17.18 ± 10.53
23.71 ± 6.85
< 0.001a
< 20 mm
81(54.73)
1(5.26)
≥ 20 mm
67(45.27)
18(94.73) Low-risk group (n = 148)
High-risk group (n = 19)
p valuea Low-risk group (n = 148)
High-risk group (n = 19)
p valuea Values are presented as number, number(percent), or mean ± standard deviation a Mann–Whitney U test; LND number of lymph nodes dissected, LVI lymphovascular invasion, sm1 inva-
sion of the upper third of the submucosal layer or reaching the submucosal layer > 200 µm from the muscu-
laris, sm2 invasion reaching the middle third of the submucosal layer, sm3 invasion reaching the lower third
of the submucosal layer Table 3 Multivariate analysis of factors predictive of low risk (nega-
tive lymph node metastasis and recurrence-free survival) following
endoscopic submucosal resection for esophageal squamous cell car-
cinoma Table 3 Multivariate analysis of factors predictive of low risk (nega-
tive lymph node metastasis and recurrence-free survival) following
endoscopic submucosal resection for esophageal squamous cell car-
cinoma thresholds for endoscopic treatment in these select T1b
patients. The biological features of clinical N0 submucosal esopha-
geal SCC are key to determining the feasibility of endoscopic
treatment. Discussion The high incidence of complications after surgery for
esophageal cancer remains a challenge. In most large-scale
studies, the incidence of postoperative complications was
approximately 40% [8]. Although advances in minimally
invasive resection of esophageal SCC have improved
patients’ postoperative quality of life and decreased the
incidence of pulmonary complications, overall mortal-
ity rates have not changed dramatically [12, 13]. Radical
treatment for esophageal SCC includes complete removal
of the primary tumor and thorough lymph node dissection
or inactivation. Discussion 2 Overall survival in
low- and high-risk patients
with clinical N0 pathological
T1b esophageal squamous cell
carcinoma after endoscopic sub-
mucosal resection. OS overall
survival
Table 4 Differences between G1S<20 and G2–3S>20 patients
n number, G1 high differentiation, G2–3S>20 low differentiation and
tumor length > 20 mm, LVI lymphovascular invasion, sm1 invasion of
the upper third of the submucosal layer or reaching the submucosal
layer > 200 µm from the muscularis, S<20 tumor length < 20 mm
Sm1 G1S<20 (n = 21)
Others
(n = 146)
Lymph node metastases
0
5
LVI
0
10
Recurrence
0
17 Fig. 2 Overall survival in
low- and high-risk patients
with clinical N0 pathological
T1b esophageal squamous cell
carcinoma after endoscopic sub-
mucosal resection. OS overall
survival Fig. 2 Overall survival in
ow- and high-risk patients
with clinical N0 pathological
T1b esophageal squamous cell
carcinoma after endoscopic sub-
mucosal resection. OS overall
urvival Table 4 Differences between G1S<20 and G2–3S>20 patients
n number, G1 high differentiation, G2–3S>20 low differentiation and
tumor length > 20 mm, LVI lymphovascular invasion, sm1 invasion of
the upper third of the submucosal layer or reaching the submucosal
layer > 200 µm from the muscularis, S<20 tumor length < 20 mm
Sm1 G1S<20 (n = 21)
Others
(n = 146)
Lymph node metastases
0
5
LVI
0
10
Recurrence
0
17 can be used both in the primary tumor diagnosis and in the
treatment regime for superficial lesions. Table 4 Differences between G1S<20 and G2–3S>20 patients
n number, G1 high differentiation, G2–3S>20 low differentiation and
tumor length > 20 mm, LVI lymphovascular invasion, sm1 invasion of
the upper third of the submucosal layer or reaching the submucosal
layer > 200 µm from the muscularis, S<20 tumor length < 20 mm
Sm1 G1S<20 (n = 21)
Others
(n = 146)
Lymph node metastases
0
5
LVI
0
10
Recurrence
0
17 i
To our knowledge, our study is the largest single-center
study of patients with cN0pT1b esophageal SCC (n = 167). Because the overall lymph node metastasis rate in our
patients (cN0pT1b) was 3% (5/167), R0 resection in patients
with cN0pT1b lesions based only on clinical N0 findings is
insufficient. Therefore, it is extremely important to identify
additional patients at high risk of lymph node metastasis
and recurrence. Discussion However, less is known about the biological fea-
tures of cN0pT1b esophageal SCC. Some studies evaluated
small numbers of patients with esophageal adenocarcinoma
[15, 16], while others included larger numbers and evaluated
patients undergoing endoscopic submucosal resection for
either T1a or T1b superficial esophageal adenocarcinoma
[4, 17–20]. Two studies evaluating larger numbers of T1b
patients did not evaluate cN0pT1b patients, specifically [5,
7]. More importantly, these studies did not include subgroup
analyses. Because radical endoscopic treatment targets cN0
patients, oncological studies in patients with cN0 lesions
can help determine the feasibility of endoscopic treatment. CI confidence interval, OR odds ratio, sm1 invasion of the upper third
of the submucosal layer or reaching the submucosal layer > 200 µm
from the muscularis
Variable
OR
95% CI
p value
Differentiation
0.138
0.085–0.524
< 0.001*
Depth of invasion (sm1)
0.246
0.115–0.634
< 0.001*
Tumor length (< 20 mm)
1.085
1.142–1.231
< 0.001* CI confidence interval, OR odds ratio, sm1 invasion of the upper third
of the submucosal layer or reaching the submucosal layer > 200 µm
from the muscularis with submucosal esophageal carcinoma, no consensus has
been reached regarding endoscopic submucosal resection
of submucosal esophageal cancers [14]. Our retrospective
analysis of patients with clinical N0 submucosal esophageal
SCC identified a low-risk subgroup and provided diagnostic with submucosal esophageal carcinoma, no consensus has
been reached regarding endoscopic submucosal resection
of submucosal esophageal cancers [14]. Our retrospective
analysis of patients with clinical N0 submucosal esophageal
SCC identified a low-risk subgroup and provided diagnostic Esophageal endoscopic ultrasonography (EUS) is gener-
ally considered the best tool for staging superficial esoph-
ageal lesions. In this study, all patients underwent EUS 1 3 598 Surgical Endoscopy (2021) 35:593–601 598
Surgical Endoscopy (2021) 35:593 601
can be used both in the primary tumor diagnosis and in the
treatment regime for superficial lesions. To our knowledge, our study is the largest single-center
study of patients with cN0pT1b esophageal SCC (n = 167). Because the overall lymph node metastasis rate in our
patients (cN0pT1b) was 3% (5/167), R0 resection in patients
with cN0pT1b lesions based only on clinical N0 findings is
insufficient. Therefore, it is extremely important to identify
additional patients at high risk of lymph node metastasis
and recurrence. Our study indicated that the degree of tumor
differentiation, invasion depth, and lesion size were risk fac-
t
f
th l
i
l l
h
d
t
t
i
d
Fig. Discussion Additionally, prospective studies are needed to
clarify which patients could benefit from endoscopic resec-
tion followed by esophagectomy.i tumor differentiation, and tumor length < 2 cm experienced
lymph node metastasis, and no patients experienced recur-
rence, indicating these measures as diagnostic thresholds for
endoscopic submucosal resection. Therefore, simple endo-
scopic submucosal resection may be sufficient for superficial
lesions with sm1 invasion, high differentiation, and tumor
length < 2 cm, which were the diagnostic thresholds for
extended endoscopic treatment in these select T1b patients
identified in our study. In contrast, surgical resection with
extended thoracic and abdominal lymph node dissection
remains the optimal treatment for high-risk patients with
submucosal esophageal SCC. Postoperative recurrences, particularly micrometastases,
provide important clues for analyzing the scope of tumor
invasion. Although our patients underwent radical thoracic
and abdominal lymph node dissection, 8.4% (14/167) of
patients experienced disease recurrence in the pN0 group. In this study, we classified patients with lymph node metas-
tasis and/or distant recurrence as the high-risk group, and
all others as the low-risk group. Univariate and multivari-
ate analyses showed that degree of differentiation, invasion
depth, and tumor length differed significantly between these
two groups. Only 21/167 patients (12.6%) in our study met
all three conditions for our diagnostic thresholds for endo-
scopic submucosal resection (i.e., sm1 invasion, high dif-
ferentiation, and tumor length < 2 cm). These 21 patients
experienced no lymph node metastasis or recurrence, there-
fore, endoscopic submucosal dissection with negative resec-
tion margins may be an appropriate treatment for inoperable
low-risk patients meeting all three of the above conditions. Postoperative pathology showed that five patients had
lymph node metastases: three in the left/right recurrent
laryngeal nerve/superior mediastinum, one in the gastric car-
dia/peritoneum, and one in the carina/left or right bronchus. The three patients with recurrent laryngeal nerve/superior
mediastinal metastasis constituted 60% of our patients with
metastasis, which is a concern in the West, where dissecting
these lymph nodes is rarely performed, even in patients with
advanced disease. Rates of lymph node recurrence near the
gastric cardia and around the celiac trunk were lower than in
the superior mediastinum, showing that surgical treatment
effectively controlled metastasis to these regions. Therefore,
esophagectomy plus thorough thoracic and abdominal lymph
node dissection, followed by small T-shaped field adjuvant
radiation therapy in the neck and superior mediastinum, may
be a more reasonable option for high-risk patients. Discussion Our study indicated that the degree of tumor
differentiation, invasion depth, and lesion size were risk fac-
tors for pathological lymph node metastasis and recurrence. Subgroup analysis showed that lymph node metastasis rates
were 0, 1.4% (1/72), and 1.2% (1/82) in patients with sm1,
highly differentiated, and smaller (< 2 cm) tumors, respec-
tively; findings similar to those observed in patients with
intramucosal (T1a) esophageal SCC [6]. Although lymph
node involvement has been reported in up to 27% of patients
with sm1 tumors, results may have been affected by the num-
ber of included patients [15]. Therefore, patients with sm1,
highly differentiated, and small (< 2 cm) tumors are more
likely to benefit from endoscopic R0 resection, alone. Our
separate analysis showed that no patients with sm1, high n number, G1 high differentiation, G2–3S>20 low differentiation and
tumor length > 20 mm, LVI lymphovascular invasion, sm1 invasion of
the upper third of the submucosal layer or reaching the submucosal
layer > 200 µm from the muscularis, S<20 tumor length < 20 mm evaluation preoperatively; however, the diagnostic accuracy
of T1b was only 63.5%, preoperatively. Diagnosing the N
stage of superficial esophageal cancer appears to be more
feasible. We found that the rate of lymph node metastasis in
all T1b patients was as high as 29% (67/229) when cN+ was
included. However, after preoperative CT and ultrasound
evaluation, the postoperative pathological metastasis rate
decreased to 3% (5/167) in the cN0 population. Thus, appro-
priate N staging can provide sufficiently accurate lymph
node results and guide subsequent treatment. It is difficult to
obtain a reference value for T staging. Endoscopic resection 1 3 599 Surgical Endoscopy (2021) 35:593–601 cancer treated by endoscopic resection followed by chemo-
radiotherapy. Therefore, endoscopic resection followed by
chemoradiotherapy is now an important treatment strategy
for T1b patients with clinical N0 esophageal SCC [10]. As
a limitation, the JCOG0508 study involved only 86 (48.9%)
pT1b patients and no sm3 patients. Our study involved 167
patients with clinical N0 pathologic T1b esophageal SCC
confirmed surgically and 23 (23/167, 13.8%) sm3 patients. Our study is a good supplement to the JCOG0508 study,
but studies involving more patients are needed to confirm
our results. Discussion Additionally, no cN0 patients had lymph nodes 1 1 3 Surgical Endoscopy (2021) 35:593–601 600 cancer invading muscularis mucosa and submucosal layer. Dis
Esophagus 26:496–502 biopsied by endoscopic ultrasonography/fine needle aspira-
tion, which could also have affected accurate clinical lymph
node staging. p
g
4. Gockel I, Sgourakis G, Lyros O, Polotzek U, Schimanski CC,
Lang H, Hoppo T, Jobe BA (2011) Risk of lymph node metastasis
in submucosal esophageal cancer: a review of surgically resected
patients. Expert Rev Gastroenterol Hepatol 5:371–384 In conclusion, careful clinical stratification of diagno-
sis and treatment is required in the treatment of patients
with cN0 submucosal esophageal SCC. Simple endoscopic
submucosal resection may be sufficient for superficial
lesions with sm1 invasion, high differentiation, and tumor
length < 2 cm, which were the diagnostic thresholds for
extended endoscopic treatment in the select T1b patients
identified in our study. More study is required, specifically
randomized studies, to make any firm conclusions about
endoscopic mucosal resection in this subset of patients. In contrast, surgical resection with extended thoracic and
abdominal lymph node dissection remains the optimal treat-
ment for high-risk patients with submucosal esophageal
SCC. If lymph node metastasis is present, postoperative
adjuvant treatment targeting the neck and superior medi-
astinum may prevent tumor recurrence. 5. Qi X, Li M, Zhao S, Luo J, Shao Y, Zhang Z, Chen Y (2016)
Prevalence of metastasis in T1b esophageal squamous cell carci-
noma: a retrospective analysis of 258 Chinese patients. J Thorac
Dis 8:966–976 6. Sgourakis G, Gockel I, Lyros O, Lanitis S, Dedemadi G, Polotzek
U, Karaliotas C, Lang H (2012) The use of neural networks in
identifying risk factors for lymph node metastasis and recom-
mending management of t1b esophageal cancer. Am Surg
78:195–206 7. Eguchi T, Nakanishi Y, Shimoda T, Iwasaki M, Igaki H, Tachi-
mori Y, Kato H, Yamaguchi H, Saito D, Umemura S (2006) His-
topathological criteria for additional treatment after endoscopic
mucosal resection for esophageal cancer: analysis of 464 surgi-
cally resected cases. Mod Pathol 19:475–480 8. Wright CD, Kucharczuk JC, O’Brien SM, Grab JD, Allen MS;
Society of Thoracic Surgeons General Thoracic Surgery Data-
base (2009) Predictors of major morbidity and mortality after
esophagectomy for esophageal cancer: a Society of Thoracic Sur-
geons General Thoracic Surgery Database risk adjustment model. Discussion J Thorac Cardiovasc Surg 137:587–595 Acknowledgements We thank Jane Charbonneau, DVM, from Liwen
Bianji, Edanz Group China (www.liwenbianji.cn/ac), for editing the
English text of a draft of this manuscript. g
9. Minashi K, Nihei K, Mizusawa J, Takizawa K, Yano T, Ezoe
Y, Tsuchida T, Ono H, Iizuka T, Hanaoka N, Oda I, Morita Y,
Tajika M, Fujiwara J, Yamamoto Y, Katada C, Hori S, Doyama
H, Oyama T, Nebiki H, Amagai K, Kubota Y, Nishimura K, Kob-
ayashi N, Suzuki T, Hirasawa K, Takeuchi T, Fukuda H, Muto M
(2019) Efficacy of endoscopic resection and selective chemora-
diotherapy for stage I esophageal squamous cell carcinoma. Gas-
troenterology 157:382–390 Funding This study received funding from the Shanghai Municipal
Education Commission—Gaofeng Clinical Medicine Grant Support. Funding This study received funding from the Shanghai Municipal
Education Commission—Gaofeng Clinical Medicine Grant Support. Compliance with ethical standards 10. Kurokawa Y, Muto M, Minashi K, Boku N, Fukuda H; Gastroin-
testinal Oncology Study Group of Japan Clinical Oncology Group
(JCOG) (2009) A phase II trial of combined treatment of endo-
scopic mucosal resection and chemoradiotherapy for clinical stage
I esophageal carcinoma: Japan Clinical Oncology Group Study
JCOG0508. Jpn J Clin Oncol 39:686–689 Disclosures Dr. Bo Ye, Dr. Xiaobin Zhang, Dr. Yuchen Su, Dr. Shu-
guang Hao, Dr. Haohua Teng, Dr. Xufeng Guo, Dr. Yu Yang, Dr. Yifeng Sun, Dr. Teng Mao, and Dr. Zhigang Li have no conflicts of
interest to disclose. 11. Clavien PA, Barkun J, De Oliveira ML, Vauthey JN, Dindo D,
Schulick RD, de Santibañes E, Pekolj J, Slankamenac K, Bassi
C, Graf R, Vonlanthen R, Padbury R, Cameron JL, Makuuchi
M (2009) The Clavien-Dindo classification of surgical complica-
tions: five-year experience. Ann Surg 250:187–196 Open Access This article is licensed under a Creative Commons Attri-
bution 4.0 International License, which permits use, sharing, adapta-
tion, distribution and reproduction in any medium or format, as long
as you give appropriate credit to the original author(s) and the source,
provide a link to the Creative Commons licence, and indicate if changes
were made. The images or other third party material in this article are
included in the article’s Creative Commons licence, unless indicated
otherwise in a credit line to the material. If material is not included in
the article’s Creative Commons licence and your intended use is not
permitted by statutory regulation or exceeds the permitted use, you will
need to obtain permission directly from the copyright holder. To view a
copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. i
12. Takeuchi H, Miyata H, Gotoh M, Kitagawa Y, Baba H, Kimura W,
Tomita N, Nakagoe T, Shimada M, Sugihara K, Mori M (2014)
A risk model for esophagectomy using data of 5354 patients
included in a Japanese nationwide web-based database. Ann Surg
260:259–266 13. Biere SS, van Berge Henegouwen MI, Maas KW, Bonavina L,
Rosman C, Garcia JR, Gisbertz SS, Klinkenbijl JH, Hollmann
MW, de Lange ES, Bonjer HJ, van der Peet DL, Cuesta MA
(2012) Minimally invasive versus open oesophagectomy for
patients with oesophageal cancer: a multicentre, open-label, ran-
domised controlled trial. Lancet 379:1887–1892 Discussion In this study, the overall incidence of postoperative com-
plications was 41.3%, and involved anastomotic leak in
16.7% and respiratory insufficiency in 6% of the patients. No patients died within 90 days postoperatively, and the
3-year overall survival rate for the low- and high-risk groups,
inclusive, was 86.9%. Therefore, surgery yielded good early
outcomes and long-term survival indicating that, for patients
with high-risk submucosal esophageal SCC, endoscopic
treatment, even when followed by adjuvant chemoradio-
therapy, was not as effective in controlling tumors as there
was a surgical resection with extended thoracic and abdomi-
nal lymph node dissection, and postoperative cervical and
upper mediastinal adjuvant radiotherapy. These survival
results support using our diagnostic thresholds for extended
endoscopic treatment in our defined low-risk T1b group. No consensus has yet been reached regarding treatment
after endoscopic submucosal resection in patients with N0
high-risk submucosal esophageal SCC (> sm1, low degree
of differentiation and tumor length > 2 cm). The adequacy
of adjuvant chemoradiotherapy as a salvage treatment has
not been well-documented [3, 9, 21]; however, our results
suggest that salvage adjuvant chemoradiotherapy may be
inadequate. First, most of the metastatic lymph nodes in our
patients were distributed near the superior mediastinum or
recurrent laryngeal nerve (3/5, 60%) and gastric cardia/left
gastric artery (1/5, 20%). These findings were consistent
with metastases of the submucosal esophageal SCC upward
and downward following the long axis of the esophagus [22]. After endoscopic submucosal dissection, adjuvant radio-
therapy alone in the area of the primary lesion cannot com-
pletely cover both areas, and extensive irradiation in multiple
fields may increase toxicity. Furthermore, adjuvant chemo-
therapy has a limited role in controlling lymph node metasta-
ses in esophageal SCC. These findings suggest that surgical
esophageal resection plus radical thoracic and abdominal
lymph node dissection may be more effective in controlling
these tumors. However, the results of the JCOG0508 study
showed excellent long-term outcomes for T1b esophageal i
This study has several limitations, namely, its single-
center, retrospective design, and the lack of accurate clinical
staging, which meant we were unable to compare outcomes
of surgical vs non-surgical treatments in our patients with
cN0pT1b esophageal SCC. Additionally, the number of sm1
patients was low. Another limitation is the cN0 classifica-
tion without staging using positron emission tomography,
therefore, some cN0 patients may have been understaged in
our study. 21. Mochizuki Y, Saito Y, Tsujikawa T, Fujiyama Y, Andoh A (2011)
Combination of endoscopic submucosal dissection and chemora-
diation 7therapy for superficial esophageal squamous cell carci-
noma with submucosal invasion. Exp Ther Med 2:1065–1068 Publisher’s Note Springer Nature remains neutral with regard to
jurisdictional claims in published maps and institutional affiliations. 22. Tanaka T, Matono S, Nagano T, Shirouzu K, Fujita H, Yamana H
(2012) Esophagectomy with extended lymphadenectomy for sub-
mucosal esophageal cancer: long-term outcomes and prognostic
factors. Ann Surg Oncol 19:750–756 References 14. Pennathur A, Farkas A, Krasinskas AM, Ferson PF, Gooding
WE, Gibson MK, Schuchert MJ, Landreneau RJ, Luketich JD
(2009) Esophagectomy for T1 esophageal cancer: outcomes in
100 patients and implications for endoscopic therapy. Ann Thorac
Surg 87:1048–1054 1. Takubo K, Aida J, Sawabe M, Kurosumi M, Arima M, Fujishiro
M, Arai T (2007) Early squamous cell carcinoma of the oesopha-
gus: the Japanese viewpoint. Histopathology 51:733–742 15. Nentwich MF, von Loga K, Reeh M, Uzunoglu FG, Marx A,
Izbicki JR, Bogoevski D (2014) Depth of submucosal tumor
infiltration and its relevance in lymphatic metastasis formation
for T1b squamous cell and adenocarcinomas of the esophagus. J
Gastrointest Surg 18:242–249 2. Tachibana M, Hirahara N, Kinugasa S, Yoshimura H (2008) Clin-
icopathologic features of superficial esophageal cancer: results of
consecutive 100 patients. Ann Surg Oncol 15:104–116 3. Yoshii T, Ohkawa S, Tamai S, Kameda Y (2013) Clinical outcome
of endoscopic mucosal resection for esophageal squamous cell 3 Surgical Endoscopy (2021) 35:593–601 601 21. Mochizuki Y, Saito Y, Tsujikawa T, Fujiyama Y, Andoh A (2011)
Combination of endoscopic submucosal dissection and chemora-
diation 7therapy for superficial esophageal squamous cell carci-
noma with submucosal invasion. Exp Ther Med 2:1065–1068 16. Lee L, Ronellenfitsch U, Hofstetter WL, Darling G, Gaiser T, Lip-
pert C, Gilbert S, Seely AJ, Mulder DS, Ferri LE (2013) Predict-
ing lymph node metastases in early esophageal adenocarcinoma
using a simple scoring system. J Am Coll Surg 217:191–199 g
p
g y
g
17. Aadam AA, Abe S (2018) Endoscopic submucosal dissection
for superficial esophageal cancer. Dis Esophagus. https://doi. org/10.1093/dote/doy021i 22. Tanaka T, Matono S, Nagano T, Shirouzu K, Fujita H, Yamana H
(2012) Esophagectomy with extended lymphadenectomy for sub-
mucosal esophageal cancer: long-term outcomes and prognostic
factors. Ann Surg Oncol 19:750–756 g
y
18. Barret M, Prat F (2018) Diagnosis and treatment of superficial
esophageal cancer. Ann Gastroenterol 31:256–265 Publisher’s Note Springer Nature remains neutral with regard to
jurisdictional claims in published maps and institutional affiliations. 19. Probst A, Aust D, Märkl B, Anthuber M, Messmann H (2015)
Early esophageal cancer in Europe: endoscopic treatment by endo-
scopic submucosal dissection. Endoscopy 47:113–121 20. Sgourakis G, Gockel I, Lang H (2013) Endoscopic and surgical
resection of T1a/T1b esophageal neoplasms: a systematic review. World J Gastroenterol 19:1424–1437 1 3 1 3 3
|
https://openalex.org/W1988920972
|
https://www.redalyc.org/pdf/2032/203231729010.pdf
|
English
| null |
CREDIT ANALYSIS USING DATA MINING: APPLICATION IN THE CASE OF A CREDIT UNION
|
Journal of Information Systems and Technology Management
| 2,014
|
cc-by
| 7,883
|
JISTEM: Journal of Information Systems and
Technology Management
E-ISSN: 1807-1775
tecsi@usp.br
Universidade de São Paulo
Brasil
de Moraes Sousa, Marcos; Santana Figueiredo, Reginaldo
CREDIT ANALYSIS USING DATA MINING: APPLICATION IN THE CASE OF A CREDIT UNION
JISTEM: Journal of Information Systems and Technology Management, vol. 11, núm. 2, mayo-agosto,
2014, pp. 379-396
Universidade de São Paulo
São Paulo, Brasil
Available in: http://www.redalyc.org/articulo.oa?id=203231729010 JISTEM: Journal of Information Systems and
Technology Management
E-ISSN: 1807-1775
tecsi@usp.br
Universidade de São Paulo
Brasil
de Moraes Sousa, Marcos; Santana Figueiredo, Reginaldo
CREDIT ANALYSIS USING DATA MINING: APPLICATION IN THE CASE OF A CREDIT UNION
JISTEM: Journal of Information Systems and Technology Management, vol. 11, núm. 2, mayo-agosto,
2014, pp. 379-396
Universidade de São Paulo
São Paulo, Brasil
Available in: http://www.redalyc.org/articulo.oa?id=203231729010 JISTEM: Journal of Information Systems and
Technology Management
E-ISSN: 1807-1775
tecsi@usp.br
Universidade de São Paulo
Brasil de Moraes Sousa, Marcos; Santana Figueiredo, Reginaldo
CREDIT ANALYSIS USING DATA MINING: APPLICATION IN THE CASE OF A CREDIT UNION
JISTEM: Journal of Information Systems and Technology Management, vol. 11, núm. 2, mayo-agosto,
2014, pp. 379-396
Universidade de São Paulo
São Paulo, Brasil de Moraes Sousa, Marcos; Santana Figueiredo, Reginaldo
REDIT ANALYSIS USING DATA MINING: APPLICATION IN THE CASE OF A CREDIT UNION
EM: Journal of Information Systems and Technology Management, vol. 11, núm. 2, mayo-agosto,
2014, pp. 379-396
Universidade de São Paulo
São Paulo, Brasil Available in: http://www.redalyc.org/articulo.oa?id=203231729010 How to cite
Complete issue
More information about this article
Journal's homepage in redalyc.org
Scientific Information System
Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal
Non-profit academic project, developed under the open access initiative Scientific Information System Scientific Information System
Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal
Non-profit academic project, developed under the open access initiative JISTEM - Journal of Information Systems and Technology Management
Revista de Gestão da Tecnologia e Sistemas de Informação
Vol. 11, No. 2, May/Aug., 2014 pp. 379-396
ISSN online: 1807-1775
DOI: 10.4301/S1807-17752014000200009 CREDIT ANALYSIS USING DATA MINING: APPLICATION IN
THE CASE OF A CREDIT UNION Marcos de Moraes Sousa
Instituto Federal Goiano Campus Ceres, Goiás, Brasil
Reginaldo Santana Figueiredo
Universidade Federal de Goiás, Goiás, Brasil Marcos de Moraes Sousa, Professor in Administration, Federal Institute of Goiás; Ph.D. candidate, University of
Brasília. Works on projects related to public administration, quantitative methods, and analysis of organizational
performance. E-Mail: lceara@hotmail.com Reginaldo Santana Figueiredo, Post-doctoral fellow in Modeling and Simulation, Department of Industrial and
Systems Engineering, Texas A&M University, IE-TAMU, USA (2002), Ph.D., Industry Economics, Federal
University of Rio de Janeiro (UFRJ); Associate Professor, Federal University of Goiás—UFG. He was also a
consultant for the Brazilian government on the analysis of production chains and for the Department of Recreation,
Park and Tourism Science of Texas A&M University, in the analysis of tourism's socioeconomic impact, using
modeling and simulation techniques. E-mail: santanrf@uol.com.br Address for correspondence / Endereço para correspondência _________________________________________________________________________________
Manuscript first received/Recebido em: 17/07/2012 Manuscript accepted/Aprovado em: 21/03/2014 Keywords: Credit Unionism; Data Mining; Decision Tree; Artificial Neural Network. Published by/ Publicado por: TECSI FEA USP – 2014 All rights reserved. 1. INTRODUCTION This article describes the development of models to analyze the capacity of a
credit union's associates to settle their commitments. Data mining techniques were used
to develop the models. To construct the models, the actual database of cooperative borrowers from a
SICOOB (Sistema Cooperativo Brasileiro—Brazilian Cooperative System) credit union
was used. It must be stressed that such data are difficult to access and collect. A credit cooperative or union is a society and must be guided by a social
purpose. However, it is also a financial institution and is regulated by norms imposed
by the National Monetary Council of Brazil and the Brazilian Central Bank. Moreover,
a credit union must aim to remain in the market permanently, which requires that
resources be managed efficiently. Cooperative Movement may be classified according to two concepts: the
Rochdale principle, which aims to transform society and reform man; and the
theoretical principle, developed at the University of Münster (Germany), which uses the
tools of business administration science and views the cooperative as a modern
enterprise (Pinho, 2004). From the theoretical perspective, the Münster theory is the best developed. It is
also known as the economic theory of cooperative cooperation, and its origins lie in the
Institute for Cooperative Research at the University of Münster in Germany. In
opposition to the Rochdale principle’s doctrinal assumptions, professors at the
University of Münster, together with Latin American scholars, developed a “school”
with methodological foundations that trace back to critical rationalism (Pinho, 2004). Pinho (1982, p. 75), following Bettcher, exposes the following concept of the
cooperative, based on the axioms and assumptions of the Münster theory:
“Cooperatives are groups of individuals that defend their individual economic interests
by means of a company that they jointly maintain”1. In this context, Frantz (1985:56)
adds that the cooperative may also be understood as embodying a “[...] competition
strategy aimed to maximize the results of each producer's individual economic action
[...]”. This study looks at credit unions from the perspective of the theoretical
cooperative movement and, based on its assumptions and axioms, it finds that
analyzing information for decision-making is a central condition. Tools and
methodologies aimed at analyzing managerial information have greatly evolved in
recent decades. Credit-union management is very complex because it must balance cooperative
members' yearnings and needs while competing in the market. 1 All direct quotations were translated by the authors. ABSTRACT The search for efficiency in the cooperative credit sector has led cooperatives to adopt
new technology and managerial knowhow. Among the tools that facilitate efficiency,
data mining has stood out in recent years as a sophisticated methodology to search for
knowledge that is “hidden” in organizations' databases. The process of granting credit is
one of the central functions of a credit union; therefore, the use of instruments that
support that process is desirable and may become a key factor in credit management. The
steps undertaken by the present case study to perform the knowledge discovery process
were data selection, data pre-processing and cleanup, data transformation, data mining,
and the interpretation and evaluation of results. The results were evaluated through cross-
validation of ten sets, repeated in ten simulations. The goal of this study is to develop
models to analyze the capacity of a credit union's members to settle their commitments,
using a decision tree—C4.5 algorithm and an artificial neural network—multilayer
perceptron algorithm. It is concluded that for the problem at hand, the models have
statistically similar results and may aid in a cooperative's decision-making process. Keywords: Credit Unionism; Data Mining; Decision Tree; Artificial Neural Network. Marcos de Moraes Sousa, Professor in Administration, Federal Institute of Goiás; Ph.D. candidate, University of
Brasília. Works on projects related to public administration, quantitative methods, and analysis of organizational
performance. E-Mail: lceara@hotmail.com Reginaldo Santana Figueiredo, Post-doctoral fellow in Modeling and Simulation, Department of Industrial and
Systems Engineering, Texas A&M University, IE-TAMU, USA (2002), Ph.D., Industry Economics, Federal
University of Rio de Janeiro (UFRJ); Associate Professor, Federal University of Goiás—UFG. He was also a
consultant for the Brazilian government on the analysis of production chains and for the Department of Recreation,
Park and Tourism Science of Texas A&M University, in the analysis of tourism's socioeconomic impact, using
modeling and simulation techniques. E-mail: santanrf@uol.com.br 380 Sousa, M. de M., Figueiredo, R. S. 1. INTRODUCTION A credit union’s
characteristics of being an association of members, while also being a company in the
market, must remain balanced. JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 381 Credit Analysis Using Data Mining: Application In The Case of a Credit Union The number of cooperative members and unions has been slowly increasing. According to data from the Organization of Brazilian Cooperatives (Organização das
Cooperativas Brasileiras—OCB) (2014), there are currently more than 1,047 single
credit cooperatives and 4,529 points of service in Brazil. The SICOOB is the largest
cooperative credit system in Brazil, with 529 single cooperatives and 1,949 cooperative
service points (Portal do Cooperativismo de Crédito, 2014). The dynamic and competitive environment of Brazil's financial market, together
with recent changes in credit offerings, demands a professional posture, which leads
credit unions to adopt the use of new technologies and management knowhow. Oliveira (2001) indicates that the professionalization of cooperative members
and unions is a relevant trend. The sector has developed quickly, adopting an
integration strategy using central cooperatives; thus, it must be tuned in to the most
efficient management tools. Credit analysis is one of the most important issues for financial institutions. Chaia (2003) stresses the importance of defining the type of analysis to be conducted
and its coverage, and further warns of the dangers of copying and using other
institutions' models, thus arriving at inadequate assessments. One of the foremost methods of credit assessment used by financial institutions
is credit scoring. Chaia (2003, p. 23) defines this model as the use of statistical tools to
identify the factors that determine the probability of a client going into default and
notes that their main advantage is that “[...] grant-related decisions are made based on
impersonal and standardized procedures, generating a higher degree of reliability”. Given the previously discussed concept of cooperative, the use of such objective
methodologies—such as credit scoring—in granting credit is highly relevant. Decisions
made solely by evaluating subjective assessments are avoided. Koh, Tan, and Goh
(2006) tie the progress of credit scoring to increased competitiveness, advances in
computational technology, and the exponential growth of large databases. Mester (1997) notes that model exactness, current data, and model evaluation
and readjustment are some critical factors in credit scoring and that flaws in these
factors limit the use of the model. 1. INTRODUCTION Given that lending is one of credit unions' central
functions, the analysis of that function is fundamental to protecting the cooperative's
collective assets. Obtaining tools that classify and help predict the behavior of future loans is
fundamental to credit management, helping to reduce process subjectivity, allowing
more efficient resource allocation, and resulting in quicker responses to proposals. Studies on credit analysis using data mining increase the models' precision and
have been conducted by several authors in recent years (Abellán & Mantas, 2014;
Akkoç, 2012; Bhattacharyya, Jha, Tharakunnel, & Christopher, 2011; Chang & Yeh,
2012; Chen & Huang, 2011; Crone & Finlay, 2012; Cubiles-De-La-Vega, Blanco-
Oliver, Pino-Mejías, & Lara-Rubio, 2013; García, Marqués, & Sánchez, 2012; Han,
Han, & Zhao, 2013; Koh et al., 2006; Kruppa, Schwarz, Arminger, & Ziegler, 2013;
Lai, Yu, Wang, & Zhou, 2006; Lemos, Steiner, & Nievola, 2005; Majeske & Lauer,
2013; Marqués, García, & Sánchez, 2012; Nie, Rowe, Zhang, Tian, & Shi, 2011; JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 382 Sousa, M. de M., Figueiredo, R. S. Oreski & Oreski, 2014; Saberi et al., 2013; Wang, Ma, Huang, & Xu, 2012; Xiong,
Wang, Mayers, & Monga, 2013; Yap, Ong, & Husain, 2011; Zhong, Miao, Shen, &
Feng, 2014; Zhou, Jiang, Shi, & Tian, 2011; Zhu, Li, Wu, Wang, & Liang, 2013). Despite growing interest, there is still little application of this tool in
cooperatives. Khatchatourian and Treter (2010) apply fuzzy logic to their analysis of
the financial performance of production cooperatives in the Brazilian state of Rio
Grande do Sul. Zhu, Li, Wu, Wang, and Liang (2013) use a support vector machine in
their credit analysis of a credit union in Barbados. Currently, there are several data mining techniques available. Therefore, the
intention here is to examine which data mining methodology provides the best credit-
analysis results for credit unions. To this end, this study’s objective is to determine
whether a data mining model can perform well for classifying and predicting credit
unions' credit management. 2. THEORETICAL FRAMEWORK 379-396 www.jistem.fea.usp.br 383 Credit Analysis Using Data Mining: Application In The Case of a Credit Union 2013; Lemos et al., 2005; Nie et al., 2011; Wang et al., 2012; Yap et al., 2011); (c)
neural networks (Akkoç, 2012; Chen & Huang, 2011; Koh et al., 2006; Lai et al., 2006;
Nie et al., 2011; Oreski & Oreski, 2014; Saberi et al., 2013; Wang et al., 2012); (d)
support vector machines (Bhattacharyya et al., 2011; Nie et al., 2011; Xiong et al.,
2013; Zhong et al., 2014; Zhu et al., 2013); and (e) ensemble methods (Abellán &
Mantas, 2014; García et al., 2012; Marqués et al., 2012; Nie et al., 2011; Wang et al.,
2012). 2013; Lemos et al., 2005; Nie et al., 2011; Wang et al., 2012; Yap et al., 2011); (c)
neural networks (Akkoç, 2012; Chen & Huang, 2011; Koh et al., 2006; Lai et al., 2006;
Nie et al., 2011; Oreski & Oreski, 2014; Saberi et al., 2013; Wang et al., 2012); (d)
support vector machines (Bhattacharyya et al., 2011; Nie et al., 2011; Xiong et al.,
2013; Zhong et al., 2014; Zhu et al., 2013); and (e) ensemble methods (Abellán &
Mantas, 2014; García et al., 2012; Marqués et al., 2012; Nie et al., 2011; Wang et al.,
2012). 2013; Lemos et al., 2005; Nie et al., 2011; Wang et al., 2012; Yap et al., 2011); (c)
neural networks (Akkoç, 2012; Chen & Huang, 2011; Koh et al., 2006; Lai et al., 2006;
Nie et al., 2011; Oreski & Oreski, 2014; Saberi et al., 2013; Wang et al., 2012); (d)
support vector machines (Bhattacharyya et al., 2011; Nie et al., 2011; Xiong et al.,
2013; Zhong et al., 2014; Zhu et al., 2013); and (e) ensemble methods (Abellán &
Mantas, 2014; García et al., 2012; Marqués et al., 2012; Nie et al., 2011; Wang et al.,
2012). The studies' real application contexts were obtained from organizations in
Canada (Xiong et al., 2013), Germany (Han et al., 2013; Koh et al., 2006), Croatia
(Oreski & Oreski, 2014), Peru (Cubiles-De-La-Vega et al., 2013), China (Nie et al.,
2011), Turkey (Akkoç, 2012), and Barbados (Zhu et al., 2013). Credit analysis using
data mining is still rare in Brazil: Lemos et al. (2005) find the same methodology being
employed for bank credit analysis, using a branch office of Banco do Brasil as their
locus. 2. THEORETICAL FRAMEWORK The term knowledge discovery in databases (KDD) was first used in 1989 to
stress that knowledge is the final product of the discovery process in databases (Fayyad,
Piatetsky-Shapiro, & Smyth, 1996). Until 1995, the terms KDD and data mining were understood by many authors
as synonymous (Lemos et al., 2005). Fayyad et al. (1996) defines and distinguishes
KDD and data mining as follows: the former refers to the general process of
discovering useful knowledge from data, whereas the latter refers to the specific
application of algorithms to extract patterns and models from data. In the view of these
authors, data mining thus is a step in the KDD process that consists of applying
algorithms in the production of a particular set of patterns and models. Fayyad et al. (1996) refer to patterns as model components. This study used the
concept of model defined by Pidd (1998, p. 23): “A model is an external and explicit
representation of part of a reality, observed by a person who wishes to use that model to
understand, alter, manage, and control part of that reality”. Goldschmidt and Passos (2003, p. 6) split KDD activities into three groups: (i)
technological development, a group that incorporates “[...] the initiatives for
conception, betterment and development of algorithms, support tools and technologies
[...]” into the KDD process; (ii) KDD execution, a group composed of activities related
to using algorithms, tools, and technologies developed in the search of knowledge; (iii)
application of results, as a group that consists of the models developed in the KDD
execution, in a such way that “[...] the activities turn toward the application of results in
the context in which the KDD process was conducted”. Hybrid or composite techniques and models are usually compared. The
following models of credit and risk analysis stand out: (a) logistic regression (Akkoç,
2012; Bhattacharyya et al., 2011; Cubiles-De-La-Vega et al., 2013; Han et al., 2013; Ju
& Sohn, 2014; Koh et al., 2006; Kruppa et al., 2013; Nie et al., 2011; Wang et al.,
2012; Yap et al., 2011); (b) decision trees (Abellán & Mantas, 2014; Bhattacharyya et
al., 2011; Chen & Huang, 2011; Crone & Finlay, 2012; Koh et al., 2006; Kruppa et al., JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 2. THEORETICAL FRAMEWORK Decision trees are one of the most prominent and popular data mining methods
(Wang et al., 2012). According to Lemos et al. (2005, p. 229), a decision tree is the
only method that provides results in a hierarchical manner; i.e., “[...] the most relevant
attribute is placed in the first node of the tree, and less relevant attributes are placed in
subsequent nodes”. A decision tree is therefore a structure that is used to split a large
amount of data into successive, smaller sets by applying a sequence of decision rules
(Berry & Linoff, 2004). The construction of decision trees is especially attractive in the KDD context,
which according to Gehrke (2003) is attributable to the following reasons: intuitive and
easy-to-understand results; non-parametric properties that are therefore applicable to
exploratory treatments; relatively fast construction when compared to other methods;
and accuracy that can be compared to the accuracy of other models. Decision trees are commonly converted into decision rules. A decision tree may
be observed as: [...] a graph in which each non-leaf node represents a predicate
(condition) involving an attribute and a set of values. The leaf
nodes correspond to the attribution of a value or set of values to
a problem attribute (Goldschmidt & Passos, 2005, p. 57). [...] a graph in which each non-leaf node represents a predicate
(condition) involving an attribute and a set of values. The leaf
nodes correspond to the attribution of a value or set of values to
a problem attribute (Goldschmidt & Passos, 2005, p. 57). In light of this observation, paths in the tree correspond to rules of the type, “IF
<conditions> THEN <conclusion>”. Several algorithms have been developed based on
the induction of decision trees, among which the following stand out: C4.5, CART
(classification and regression trees), QUEST (quick, unbiased, efficient statistical trees)
and CHAID (chi-square automatic interaction detectors). An artificial neural network (ANN) is a mathematical model based on the brain
structure, ordered into layers and connections. The origin of ANNs dates back to 1943,
but it was in the 1980s that greater interest in the method appeared, its development JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 384 Sousa, M. de M., Figueiredo, R. S. fostered mainly by advances in information technology (Braga, Carvalho, & Ludermir,
2000). In Goldschmidt and Passos's (2005, p. 2. THEORETICAL FRAMEWORK 175) view, ANNs can be observed as
“[...] mathematical models inspired by the working principles of biological neurons and
the brain's structure”. Such models, according to those authors, allow the simulation of
human abilities such as learning, generalizing, associating, and abstracting. Braga et al. (2000, p. 1) define ANNs as “distributed parallel systems composed
of simple processing units (nodes) that compute some given (usually non-linear)
mathematical function, [...] arranged into one or more layer and interconnected by a
large number of connections [...]” An ANN's structure therefore consists of neuron layers and weighted
connections. As shown in Figure 1, neurons are represented by nodes and weighted
connections are represented by arrows. Figure 1 – ANN architecture
Source: Goldschmidt & Passos (2005). Figure 1 – ANN architecture Source: Goldschmidt & Passos (2005). Source: Goldschmidt & Passos (2005). Typically, there are three stages of ANN processing: the input layer, in which
the data are received; the internal layer, usually called the hidden layer, which is
responsible for processing the data and may consist of more than one actual layer; and
the output layer, which provides the result (Larose, 2005). The first step when applying ANNs is the network's learning phase, in which
parameters are adjusted. This learning may be of two types: supervised or
unsupervised. The first type occurs when output (or target) variables' values are
provided, the second type occurs in the absence of those values. Braga et al. (2000, p. 227) mention as positive points, which arouse interest in
the method, the ability to learn and later to generalize the possibility of mapping JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 385 Credit Analysis Using Data Mining: Application In The Case of a Credit Union multivariable functions, self-organization, the process of time-series, the possibility of
using a large number of input variables, and the possibility of using samples. Because
the model is considered non-parametric, these authors further stress, “[...] there is no
great need to understand the process itself”. However, these authors also consider this
last aspect to constitute the primary criticism of the model; i.e., the model's inability to
clarify how its results are generated. Due to this peculiarity, ANNs are also called
“black boxes”. JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 3. In this research, we opted to use case studies, which according to Yin (2010),
are adequate to study contemporary events in a real-life context when controlling
variables becomes more difficult for the researcher. This case study is unique and
contemplates one unit of analysis, which involves one Credit Union of the SICOOB
system—structured to contemplate investigation into the union from the perspective of
theoretical cooperative movement. The cooperative's database was used to evaluate the credit analysis system's
performance. This database comprises the historical data of natural persons' analyses
from 2003 to 2007. Due to a change in the information system, it was not possible to
gather data from before this period. Data referring to credit analysis is highly confidential and strategic, due to
banking secrecy and the risk of competitors acquiring the data. This makes such data
very difficult for third parties to obtain. The choice to study a cooperative was therefore
due to its willingness to provide the data. The cooperative currently uses the SisBr application of the SICOOB system as a
credit analysis tool. This application contains the information used by management and
the board of directors to make decisions about whether to grant credit. The study followed the steps suggested by Fayyad, Piatetsky-Shapiro, and
Smyth (1996) for the knowledge discovery process: data selection, data pre-processing
and cleanup, data transformation, data mining, data interpretation, and the evaluation of
results. To reach its goals, this study was based on the activities involved in conducting
KDD, as discussed by Goldschmidt and Passos (2005). Among the available data
mining techniques, neural networks and decision trees were used, both of which are
common in empirical studies. Data collection and selection corresponded to the process of capturing,
organizing, and selecting the data made available for the modeling and data-mining
phases, and thus required accurate examination. Dasu and Johnson (2003) note the
following factors that are helpful in analyzing variables: previous experience,
knowledge, quantity of results, and quality of results. JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 386 Sousa, M. de M., Figueiredo, R. S. 3. RESULTS This section describes the simulation results of the techniques investigated in
this article—namely, the decision tree and ANN techniques—along with the statistical
tests comparing them. No missing values are found in the database. Chart 01 shows the structure of the
constructed database, together with its variables and their possible values. 3. RESULTS de M., Figueiredo, R. S. Chart 01 - Database structure (Cont.)
CODE
VARIABLE
VALUE
33
Result—January 2008
1= good standing
2= default
34
Result—February 2008
1= good standing
2= default
35
Result—March 2008
1= good standing
2= default
36
Result—April 2008
1= good standing
2= default
37
Result—May 2008
1= good standing
2= default
38
Result—June 2008
1= good standing
2= default
39
Aggregate result
1= good standing
2= default
Source: Study data, 2010 Chart 01 - Database structure (Cont.) The output vector is given by variables 27 to 39, corresponding to the period
from July 2007 through June 2008. Variables 02 and 10 are not part of the credit
analysis conducted by the cooperative and were added to broaden the analysis. These
variables were gathered from cooperative members' records and represent the data
made available by the cooperative. Variables 11 through 26 are currently used for credit analysis and represent the
cooperative member's borrowing history. Codes 27 through 39 represent the output
variable adopted in the study and depict the period from July 2007 through June 2008. These are the data that the cooperative provided. Older data were not available. The number of variables used in the analysis was consistent with other studies. For example, Koh et al. (2006) used 20 variables, and Lemos et al. (2005) used 24. The variable “cooperative member code” was discarded because it was useful
only to identify individuals while collecting data. The variable “attributed risk” was
used only in the data pre-processing and cleanup stages; it was not used in the
transformation and modeling stages because it refers to the output of the model used by
the cooperative, and therefore it represents the result of the model currently being used. The variable “aggregate results” represents the result of the period of analysis (July
2007 through June 2008) and according to the cooperative's business rules and the
study's goals, is the model's target output variable. Data transformation aims to help carry out the data mining techniques. As
recommended by Goldschmidt and Passos (2005), data were grouped into a single two-
dimensional table. The data were collected from two sources in the cooperative: first, from credit
assessment; and second, from records gathered manually, record by record. In this
survey, historical data from 211 individual members were used, out of which 22 were
in default and 189 were in good standing. 3. RESULTS Chart 01 - Database structure
CODE
VARIABLE
VALUE
01
Member code
Numerical key, unique for each member
02
Gender
1= male
2= female
03
Age
Numerical value
04
Level of education
1= graduate
2= complete tertiary
3= incomplete tertiary
4= complete secondary
5= incomplete secondary
6= complete primary
7= incomplete primary
05
City
Name of city of residence
06
Birthplace
Name of city of birth
07
Place of residence
1= urban area
2= rural area
08
Primary work/activity
Name of work/activity
09
Marital status
1= Married
2= Single
3= Widowed
4= Legally divorced
5= Other
10
Capital
Numerical value
11
Relationship
1= with the cooperative for more than 3 years
2= with the cooperative for 1 to 3 years
3= with the cooperative for less than 1 year
12
Transaction conduct
1= normal
2= occasional delays
3= constant delays/renegotiations
13
Years of experience in activity/work
1= more than 5 years
2= from 3 to 5 years
3= less than 3 years
14
Records check
1= no restrictions
2= justified, irrelevant restrictions
3= relevant or unjustified, irrelevant restrictions
15
Record information at the
cooperative
1= up-to-date and reliable record
2= up-to-date and unreliable record
3= information is not up-to-date or is missing
16
Purpose of the operation
1= support and investment
2= financing of assets
3= personal credit/automatic loan
4= debt renewal/composition Chart 01 - Database structure Credit Analysis Using Data Mining: Application In The Case of a Credit Union 387 JISTEM Brazil Vol 11 No 2 May/Aug 2014 pp 379-396
www jistem fea usp br
Chart 01 - Database structure (Cont.)
CODE
VARIABLE
VALUE
17
Operation guarantees
1= mortgage—social capital
2= chattel mortgage/warrants
3= pledge/collateral
4= personal
18
Liquidity guarantee
1= high liquidity guarantee (sale in less than 6 months)
2= moderate liquidity guarantee (sale in 6 to 12 months)
3= personal or low liquidity guarantee (sale in more
than 12 months)
19
Frequency with which the member
performs (active) transactions
1= never
2= frequently
3= permanently
20
Operation value
1= up to 1% of adjusted net worth (ANW)
2= from 1.01% to 2% of ANW
3= from 2.01% to 3% of ANW
4= more than 3% of ANW
21
Level of commitment—installments
on member's net income
1= up to 20% of average net income
2= from 20%-30% of average net income
3= more than 30% of net income
22
Personal net assets minus total
liability
1= more than 4 times
2= from 2 to 4 times
3= no personal equity or less than 2 times
23
Total liability in relation to annual
net income
1= less than 2 times
2= from 2 to 4 times
3= more than 4 times
24
Total liability in relation to paid-in
capital
1= less than 4 times
2= from 4 to 8 times
3= from 8 to 12 times
4= more than 12 times
25
Profile of member's economical
activity
1= excellent
2= good
3= regular
4= poor
26
Risk attributed by the cooperative
1= AA
2= A
3= B
4= C
5= D
6= E
7= F
8= G
9= H
27
Result—July 2007
1= good standing
2= default
28
Result—August 2007
1= good standing
2= default
29
Result—September 2007
1= good standing
2= default
30
Result—October 2007
1= good standing
2= default
31
Result—November 2007
1= good standing
2= default
32
Result—December 2007
1= good standing
2= default 388 Sousa, M. 3. RESULTS This data represents all of the cooperative’s
member-borrowers. Given the difference in numbers between default and good JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 389 Credit Analysis Using Data Mining: Application In The Case of a Credit Union standing, there may be bias and overfitting problems (Chawla, 2005; Horta, Borges,
Carvalho, & Alves, 2011). To solve this problem, a technique called SMOTE (synthetic
minority oversampling technique) (Chawla, 2005) was used to insert observations of
cooperative members in default. This algorithm is one of the most used in the literature
(Horta et al., 2011). Thus, 110 observations of the minority class—i.e., members in
default—were created, and the sample totaled 321 observations, out of which 132 were
in default and 189 were in good standing. Next, the database was randomized to avoid a
concentration of the same values into a given data set while cross-validating, which
would have led to overfitting. For the computational implementation of the decision tree and neural network
techniques, the database described in this study was used, taking into consideration, for
each cooperative member, the previously described variables. For example, a model
generated by the decision tree technique was selected for transformation into decision
rules during the post-processing phase. The public domain computational tool WEKA
(Waikato environment for knowledge analysis) was chosen to perform this task. Goldschmidt and Passos (2005, p. 50) argue that for a more reliable evaluation
of the knowledge model, “[...] the data used in constructing the model should not be the
same as used in this model's evaluation”. Those authors further state that there should
be at least two divisions: training and testing. The first division comprises the data used
in constructing the model; the second division comprises the data for evaluation. Splitting the data set served to simplify, summarize and reduce the database's
size and variability, resulting in the selection of more sophisticated and accurate models
(Dasu & Johnson, 2003). In this study, to increase assessment neutrality, K-fold cross-validation was used
for both the decision tree and the ANN. According to Goldschmidt and Passos (2005, p. 51), in this method, the database is randomly split with N elements into K separate
subsets: “each of the K subsets is used as a testing set, and the remaining (K-1) subsets
are combined into a training set. The process is repeated K times, so that K models are
generated and evaluated [...]”. 3. RESULTS The data were split into ten sets and repeated across ten
simulations as proposed by Witten and Frank (2005). Cross-validation has been found
in several studies on credit analysis (Akkoç, 2012; Chang & Yeh, 2012; Han et al.,
2013). For this study, multi-layer ANNs, i.e., multilayer perceptron (MLP), were used
with the back propagation learning algorithm. The number of neurons in the input layer
was 66, plus two in the intermediate and two in the output layers. For all tests, a
learning rate of 0.01 was used, given that this rate improved classification as observed
in the simulations and was also used by Lemos et al., (2005). The momentum rate was
not used as in Lemos et al. (2005); moreover, adding this rate did not improve
classification performance. Supervised learning was used in this ANN. Ferreira (2005, p. 37) describes this
type of learning as follows: “[...] the network is trained by supplying it with input
values and the respective output values [...]. JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 390 Sousa, M. de M., Figueiredo, R. S. 390 Sousa, M. de M., Figueiredo, R. S. For a comparative analysis of the models, the total percentage of correctly
predicted values was used as the parameter in the two-tailed corrected resample t-test,
at a significance level of 0.05 (or 5%), with nine degrees of freedom, as proposed by
Witten and Frank (2005) in equation 1, presented below: (1)
where where difference between mean numbers of correctly predicted values between
the models. number of sets times number of repetitions. number of samples for testing. number of samples for training. variance of the difference between means. variance of the difference between means. 3.1 Decision Tree In this study, the J4.8 tool was chosen for use. It is the WEKA implementation of
the C4.5 decision tree algorithm. According to Goldschmidt and Passos (2005), this
tree is broadly used and accepted. A model generated by the decision tree technique was taken to exemplify the
rules and confusion matrix. The model below generated 41 leaves, i.e., sets of decision
rules of the if-then type. Some rules of the first set are shown below:
If liquidity guarantee = high guarantee liquidity (sale in less than
6 months), then default;
If liquidity guarantee = moderate guarantee liquidity (sale in 6 to
12 months) and level of commitment = up to 20% of the average net income,
then good standing;
If liquidity guarantee = moderate guarantee liquidity (sale in 6 to
12 months) and level of commitment = from 20% to 30% of the average net
income, then good standing.
If liquidity guarantee = moderate guarantee liquidity (sale in 6 to
12 months) and level of commitment = from 20% to 30% of the average net
income, then good standing. JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 391 Credit Analysis Using Data Mining: Application In The Case of a Credit Union Chart 02 shows the confusion matrix generated by the testing set of the tree
being evaluated. This matrix shows the instances classified as predicted and actual to
assess the models' hit and miss types. The main diagonal contains the correctly
classified values. The values are given as absolute numbers. Chart 02 - Confusion matrix of a model developed using the decision tree method
Predicted
Actual
Default
Good standing
Default
121
11
Good standing
8
181
Source: Study data, 2010. Chart 02 - Confusion matrix of a model developed using the decision tree method In this example, the model based on the C4.5 decision tree algorithm correctly
classified 302 records, which corresponds to accuracy rate of 94.08%, and incorrectly
classified 19 observations, or 5.92%. 3. 2. Neural Network The ANN in this study, as previously discussed in the theoretical framework,
contained three layers: input, intermediate, and output. The network used supervised
learning because the model's output values were supplied. As in the case of the decision tree, a model was used to exemplify the results
generated by the WEKA package. Chart 03 shows the confusion matrix for the model
obtained. Chart 03 - Confusion matrix for a model developed using the ANN method
Predicted
Actual
Default
Good standing
Default
118
14
Good standing
13
176
Source: Study data, 2010. Chart 03 - Confusion matrix for a model developed using the ANN method This ANN-based model, constructed using the MLP algorithm, classified 294
records correctly and 27 records incorrectly, corresponding to 91.59% and 8.41%
accuracy, respectively. JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 392 Sousa, M. de M., Figueiredo, R. S. 3. 3. Model Evaluation This section comparatively evaluates the two models developed in this study:
ANN (MLP algorithm) and decision tree (C4.5 algorithm). To conduct this evaluation,
the total percentage of correctly predicted values was used. Table 01 shows the percentage result of correctly predicted values and the
respective standard deviation of the simulations carried out using the studied models. Table 01—Comparative evaluation
Algorithm
C4.5
MLP
Correct percentage
97.07%
95.58%
Standard deviation
2.76
3.47
Source: Study data, 2010. The simulations performed using WEKA's experimenter tool indicate that the
decision tree technique implementing the C4.5 algorithm is statistically similar,
according to a two-tailed test, to the ANN with the MLP algorithm at the 0.05
significance level. Figure 02 shows WEKA's output for the simulations of the
previously described problem. Figure 02: Output for the simulations run using WEKA's experimenter tool
Source: Study data, 2010. Figure 02: Output for the simulations run using WEKA's experimenter tool
Source: Study data, 2010. The decision tree's performance for the current problem is better than the one
obtained by Yap et al. (2011), in which the error rate is 28.1%. The study by Lemos et
al. (2005), despite not performing statistical tests, obtains a higher hit rate with the
neural network than with the decision tree. Although statistically similar, decision trees
are considered to be easy to use (Lemos et al., 2005). Our results indicate that the classification models based on data mining
developed herein may be useful to the cooperative in its assessments, thus improving JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 393 Credit Analysis Using Data Mining: Application In The Case of a Credit Union performance, as previously found in the analysis of a microcredit organization
(Cubiles-De-La-Vega et al., 2013) and a credit union (Zhu et al., 2013). performance, as previously found in the analysis of a microcredit organization
(Cubiles-De-La-Vega et al., 2013) and a credit union (Zhu et al., 2013). 4. CONCLUSIONS The goal of this study is to develop and evaluate data mining models to classify
and predict the behavior of cooperative members' behavior in honoring their
obligations. The decision tree and ANN, both data mining techniques, were used to
develop the model. The process of data preparation and modeling followed the steps suggested in
the literature: data selection, data pre-processing and cleanup, data transformation, data
mining, interpretation, and validation of the results. The data were divided into training
and testing sets. Although the decision tree's accuracy in the simulations is 97.07%, compared to
95.58% with the ANN, the decision-tree-based C4.5 algorithm obtains a result that is
statistically similar to that of the model that was based on the MLP artificial neural
network. The knowledge discovery process and the use of models based on data mining
developed here may provide the cooperative with practical advantages. Understanding
the variables and their relationships may help in better classifying and predicting
cooperative members' behavior. In-depth assessment of the variables may further help
in including variables that might be important and excluding others that turn out not to
be relevant, with the advantage of providing more succinct and precise credit
management models, reducing execution time and improving decision accuracy. The
analysis of discrepant or outlier cases may be relevant to creating a new classification
or, conversely, finding undesirable patterns. This study is limited by the following issues: a lack of other cooperatives'
databases for comparison, evaluation, and validation of the model; limitations of the
information system used by the cooperative, which precluded collecting input variable
data from before 2003 and provided data referring to the output value only for the past
six months; and the lack of integration between some database modules and electronic
spreadsheets. The following proposals are left for future studies: using different databases to
validate the credit analysis model; using other data mining techniques; using hybrid
models, combining different techniques to improve classification and predictive
performance; investment analysis, evaluating the type of error and the financial impact
that the model has on the cooperative's profitability; and evaluation of discrepant cases,
particularly those cases involving the variable "capital", to check for the existence of
new patterns and classifications. JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 394 Sousa, M. de M., Figueiredo, R. S. REFERENCES Decision tree. In The handbook of data mining (pp. 3–23). New
Jersey: Lawrence Erlbaum Associates. Gehrke, J. (2003). Decision tree. In The handbook of data mining (pp. 3–23). New
Jersey: Lawrence Erlbaum Associates. Goldschmidt, R., & Passos, E. (2005). Data mining: Um guia prático. Rio de Janeiro:
Elsevier. Han, L., Han, L., & Zhao, H. (2013). Orthogonal support vector machine for credit
scoring. Engineering Applications of Artificial Intelligence, 26(2), 848–862. Horta, R. A. M., Borges, C. C. H., Carvalho, F. A. A., & Alves, F. J. S. (2011). Previsão de insolvência: Uma estratégia para balanceamento da base de dados
utilizando variáveis contábeis de empresas brasileiras. Sociedade, Contabilidade E
Gestão, 6(2), 21–36. Ju, Y. H., & Sohn, S. Y. (2014). Updating a credit-scoring model based on new
attributes without realization of actual data. European Journal of Operational
Research, 234(1), 119–126. Khatchatourian, O., & Treter, J. (2010). APLICAÇÃO DA LÓGICA FUZZY PARA
AVALIAÇÃO
ECONÔMICO-FINANCEIRA
DE
COOPERATIVAS
DE
PRODUÇÃO. Revista de Gestão Da Tecnologia E Sistemas de Informação, 7(1), 141–
162. Koh, H. C., Tan, W. C., & Goh, C. P. (2006). A two-step method to construct credit
scoring models with data mining techniques. International Journal of Business and
Information, 1(1), 96–118. Kruppa, J., Schwarz, A., Arminger, G., & Ziegler, A. (2013). Consumer credit risk:
Individual probability estimates using machine learning. Expert Systems with
Applications, 40(13), 5125–5131. Lai, K. K., Yu, L., Wang, S., & Zhou, L. (2006). Credit risk analysis using a reliability-
based neural network ensemble model. In Artificial Neural Networks-ICANN 2006 (pp. 682–690). Springer Berlin Heidelberg. Larose, T. D. (2005). Discovering knowledge in data: An introduction to data mining. New Jersey: John Wiley & Sons. Lemos, E. P., Steiner, M. T. A., & Nievola, J. C. (2005). Análise de crédito bancário
por meio de redes neurais e árvore de decisao: Uma aplicação simples de data mining. Revista de Administração Da Universidade de São Paulo, 40(3), 225–234. Majeske, K. D., & Lauer, T. W. (2013). The bank loan approval decision from multiple
perspectives. Expert Systems with Applications, 40(5), 1591–1598. Marqués, A. I., García, V., & Sánchez, J. S. (2012). Two-level classifier ensembles for
credit risk assessment. Expert Systems with Applications, 39(12), 10916–10922. Mester, L. J. (1997). What’s the point of credit scoring? Business Review, 3, 3–16. Nie, G., Rowe, W., Zhang, L., Tian, Y., & Shi, Y. (2011). Credit card churn forecasting
by logistic regression and decision tree. REFERENCES Abellán, J., & Mantas, C. J. (2014). Improving experimental studies about ensembles of
classifiers for bankruptcy prediction and credit scoring. Expert Systems with
Applications, 41(8), 3825–3830. Akkoç, S. (2012). An empirical comparison of conventional techniques, neural
networks and the three stage hybrid Adaptive Neuro Fuzzy Inference System (ANFIS)
model for credit scoring analysis: The case of Turkish credit card data. European
Journal of Operational Research, 222(1), 168–178. Berry, M. J. A., & Linoff, G. (2004). Data mining techniques: For marketing, sales and
customer relationship management (2nd ed.). Indianapolis: wiley Publishing. Bhattacharyya, S., Jha, S., Tharakunnel, K., & Christopher, J. (2011). Data mining for
credit card fraud: A comparative study. Decision Support Systems, 50(3), 602–613. Braga, A. de P., Carvalho, A. P. de L. F., & Ludermir, T. B. (2000). Redes neurais
artificiais: Teoria e aplicações. Rio de Janeiro: LTC. Chaia, A. J. (2003). Modelos de gestão de risco de crédito e sua aplicabilidade ao
mercado brasileiro. Dissertação de Mestrado. FEA/USP. Chang, S.-Y., & Yeh, T.-Y. (2012). An artificial immune classifier for credit scoring
analysis. Applied Soft Computing, 12(2), 611–618. Chawla, N. V. (2005). Data mining for imbalanced datasets: An overview. In Data
mining and knowledge discovery handbook (pp. 853–867). New Jersey: Springer. Chen, S. C., & Huang, M. Y. (2011). Constructing credit auditing and control &
management model with data mining technique. Expert Systems with Applications,
38(5359-5365). Crone, S. F., & Finlay, S. (2012). Instance sampling in credit scoring: An empirical
study of sample size and balancing. International Journal of Forecasting, 28(1), 224–
238. Cubiles-De-La-Vega, M.-D., Blanco-Oliver, A., Pino-Mejías, R., & Lara-Rubio, J. (2013). Improving the management of microfinance institutions by using credit scoring
models based on Statistical Learning techniques. Expert Systems with Applications,
40(17), 6910–6917. Dasu, T., & Johnson, T. (2003). Exploratory data mining and data cleaning. New
Jersey: John Wiley & Sons. Fayyad, U., Piatetsky-Shapiro, G., & Smyth, P. (1996). From data mining to knowledge
discovery in databases. A I Magazine, 17(3), 37–54. Ferreira, J. B. (2005). Mineração de dados na retenção de clientes em telefonia celular. Dissertação de Mestrado. PUC-RIO. García, V., Marqués, A. I., & Sánchez, J. S. (2012). On the use of data filtering
techniques for credit risk prediction with instance-based models. Expert Systems with
Applications, 39(18), 13267–13276. JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 395 Credit Analysis Using Data Mining: Application In The Case of a Credit Union Gehrke, J. (2003). REFERENCES Expert Systems with Applications, 38(12),
15273–15285. JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br 396 Sousa, M. de M., Figueiredo, R. S. OCB. (2014). Organização das Cooperativas Brasileiras. Números. Retrieved February
20, 2014, from http://www.ocb.org.br/site/ramos/credito_numeros.asp Oliveira, D. P. R. (2001). Manual de gestão de cooperativas: Uma abordagem prática. São Paulo: Atlas. Oreski, S., & Oreski, G. (2014). Genetic algorithm-based heuristic for feature selection
in credit risk assessment. Expert Systems with Applications, 41(4), 2052–2064. Pidd, M. (1998). Modelagem empresarial: Ferramentas para tomada de decisão. São
Paulo: Atlas. Pinho, D. B. (1982). O pensamento cooperativo e o cooperativismo brasileiro. CNPq/BNCC. Pinho, D. B. (2004). O cooperativismo no Brasil: Da vertente pioneira à vertente
solidaria. São Paulo: Saraiva. Portal do Cooperativismo de Crédito. (2014). Dados consolidados dos sistemas
cooperativos. Retrieved
February
20,
2014,
from
http://cooperativismodecredito.coop.br/cenario-brasileiro/dados-consolidados-dos-
sistemas-cooperativos/ Saberi, M., Mirtalaie, M. S., Hussain, F. K., Azadeh, A., Hussain, O. K., & Ashjari, B. (2013). A granular computing-based approach to credit scoring modeling. Neurocomputing, 122(25), 100–115. Wang, G., Ma, J., Huang, L., & Xu, K. (2012). Two credit scoring models based on
dual strategy ensemble trees. Knowledge-Based Systems, 26, 61–68. Witten, I. H., & Frank, E. (2005). Data mining: Practical machine learning tools and
techniques (2nd ed.). San Francisco: Elsevier. Xiong, T., Wang, S., Mayers, A., & Monga, E. (2013). Personal bankruptcy prediction
by mining credit card data. Expert Systems with Applications, 40(2), 665–676. Yap, B. W., Ong, S. H., & Husain, N. H. M. (2011). Using data mining to improve
assessment of credit worthiness. Expert Systems with Applications, 38(10), 13274–
13283. Yin, Robert, K. (2010). Estudo de caso: planejamento e métodos (4th ed.). Porto
Alegre: Bookman. Zhong, H., Miao, C., Shen, Z., & Feng, Y. (2014). Comparing the learning
effectiveness of BP, ELM, I-ELM, and SVM for corporate credit ratings. Neurocomputing, 128(27), 285–295. Zhou, X., Jiang, W., Shi, Y., & Tian, Y. (2011). Credit risk evaluation with kernel-
based affine subspace nearest points learning method. Expert Systems with
Applications, 38(4), 4272–4279. Zhu, X., Li, J., Wu, D., Wang, H., & Liang, C. (2013). Balancing accuracy, complexity
and interpretability in consumer credit decision making: A C-TOPSIS classification
approach. Knowledge-Based Systems, 52, 258–267. JISTEM, Brazil Vol. 11, No.2, May/Aug 2014, pp. 379-396 www.jistem.fea.usp.br
|
https://openalex.org/W3132836787
|
https://ora.ox.ac.uk/objects/uuid:24ff92b3-3d14-44ea-9cd8-dc584fbe467a/files/sg445cf370
|
English
| null |
Ocean Thermal Energy Conversion – Flexible Enabling Technology for Variable Renewable Energy Integration in the Caribbean
| null | 2,021
|
cc-by
| 12,385
|
Robert J. Brecha 1,2,3,4,*
, Katherine Schoenenberger 2, Masa¯o Ashtine 5
and Randy Koo cha 1,2,3,4,*
, Katherine Schoenenberger 2, Masa¯o Ashtine 5
and Randy Koon Koon 6 1
Climate Analytics, Ritterstr. 3, 10969 Berlin, Germany 1
Climate Analytics, Ritterstr. 3, 10969 Berlin, Germany
2
Hanley Sustainability Institute, University of Dayton, Dayton, OH 45469, USA;
kschoenenberger1@udayton.edu
3
Renewable and Clean Energy Program, University of Dayton, Dayton, OH 45469, USA
4
Physics Department, University of Dayton, Dayton, OH 45469, USA
5
Department of Engineering, University of Oxford, Oxford OX1 2JD, UK; masao.ashtine@oerc.ox.ac.uk
6
Department of Physics, University of the West Indies, Mona, Kingston 7, Jamaica;
randy.koonkoon@uwimona.edu.jm
*
C
d
b
t b
h @ li
t
l ti 1
Climate Analytics, Ritterstr. 3, 10969 Berlin, Germany
2
Hanley Sustainability Institute, University of Dayton, Dayton, OH 45469, USA;
kschoenenberger1@udayton.edu
3
Renewable and Clean Energy Program, University of Dayton, Dayton, OH 45469, USA
4
Physics Department, University of Dayton, Dayton, OH 45469, USA
5
Department of Engineering, University of Oxford, Oxford OX1 2JD, UK; masao.ashtine@oerc.ox.ac.uk
6
Department of Physics, University of the West Indies, Mona, Kingston 7, Jamaica;
randy.koonkoon@uwimona.edu.jm
*
Correspondence: robert brecha@climateanalytics org y
y
2
Hanley Sustainability Institute, University of Dayton, Dayton, OH 45469, USA;
kschoenenberger1@udayton.edu p
g
g
y
6
Department of Physics, University of the West Indies, Mona, Kingston 7, Jamaica;
randy.koonkoon@uwimona.edu.jm y
j
*
Correspondence: robert.brecha@climateanalytics.org Abstract: Many Caribbean island nations have historically been heavily dependent on imported
fossil fuels for both power and transportation, while at the same time being at an enhanced risk from
the impacts of climate change, although their emissions represent a very tiny fraction of the global
total responsible for climate change. Small island developing states (SIDSs) are among the leaders in
advocating for the ambitious 1.5 ◦C Paris Agreement target and the transition to 100% sustainable,
renewable energy systems. In this work, three central results are presented. First, through GIS
mapping of all Caribbean islands, the potential for near-coastal deep-water as a resource for ocean
thermal energy conversion (OTEC) is shown, and these results are coupled with an estimate of the
countries for which OTEC would be most advantageous due to a lack of other dispatchable renewable
power options. Secondly, hourly data have been utilized to explicitly show the trade-offs between
battery storage needs and dispatchable renewable sources such as OTEC in 100% renewable electricity
systems, both in technological and economic terms.
Citation: Brecha, R.J.;
Schoenenberger, K.; Ashtine, M.;
Koon Koon, R. Ocean Thermal
Energy Conversion—Flexible
Enabling Technology for Variable
Renewable Energy Integration in the
Caribbean. Energies 2021, 14, 2192. https://doi.org/10.3390/en14082192 Academic Editor: Vengatesan
Venugopal Academic Editor: Vengatesan
Venugopal Keywords: ocean thermal energy conversion; OTEC; seawater air conditioning; SWAC; desalination;
variable renewable energy; wind power; solar PV; 100% renewable energy; Caribbean Received: 24 February 2021
Accepted: 12 April 2021
Published: 14 April 2021 Robert J. Brecha 1,2,3,4,*
, Katherine Schoenenberger 2, Masa¯o Ashtine 5
and Randy Koo Finally, the utility of near-shore, open-cycle
OTEC with accompanying desalination is shown to enable a higher penetration of renewable energy
and lead to lower system levelized costs than those of a conventional fossil fuel system. Citation: Brecha, R.J.;
Schoenenberger, K.; Ashtine, M.;
Koon Koon, R. Ocean Thermal
Energy Conversion—Flexible
Enabling Technology for Variable
Renewable Energy Integration in the
Caribbean. Energies 2021, 14, 2192.
https://doi.org/10.3390/en14082192 energies energies 1. Introduction In general, technologies follow
an experience learning curve, described by decreasing costs per installed unit or per unit of
generated electricity, expressed as a function of total cumulative installed capacity [11–13]. Solar photovoltaics (PVs) represent a classic example, with installation costs dropping by
about 25% for each doubling of installed capacity, following this trend for the past four
decades [14]. Technology such as OTEC, largely still within a demonstration phase, will
inevitably be comparatively costly when factoring in more mature systems. Another factor that can also lead to hesitation on the part of developers of potential
OTEC projects is the relatively limited geographical area over which OTEC can be a viable
technology [7,8,15]. In fact, compared to wind and solar energy, it is likely that the decreases
in cost for OTEC projects may not show dramatic declines beyond those seen in moving
from experimental projects to more standardized technology implementation. For OTEC
and accompanying desalination and perhaps seawater air conditioning (SWAC) to be
implemented, developers require (i) a viable coastline resource (including the absence of
Marine Protected Areas or sensitive wetlands, for example); (ii) bathymetry that allows
for relatively deep ocean waters (~1000 m or more) within reasonable proximity (~5 km or
less); and finally, (iii) towns or fairly urbanized developments with electricity transmission
infrastructure near these coastal areas. While not likely to become a worldwide mass-market technology, OTEC and desali-
nation can play a limited but important role in complementing variable renewables in
certain cases. Therefore, bathymetric data for all island countries and overseas territories
in the Caribbean have been examined to determine which are the most likely candidates
using the three proximity criteria above, together with a fourth criterion that sufficient,
less expensive, or more developed dispatchable renewable resources (e.g., hydropower
or geothermal) are not readily available. Most crucially, this research shows at least two
reasons that OTEC should not be judged as a technology in isolation, for example in terms
of the levelized cost of electricity (LCOE) generated. y
g
The first argument for OTEC is focused on applications where the power systems
are heavily dependent on variable renewables; as such, the value of a dispatchable source
goes beyond the actual electrical energy generated, but in the ancillary services that can be
provided to the system in terms of stability. 1. Introduction Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
iations. Although responsible for a negligible fraction of historic emissions, small island devel-
oping states (SIDSs), including those in the Caribbean, have committed to fulfilling ratified
obligations outlined in the Paris Agreement. Critical reasons for the strong regional support
for the 1.5 ◦C (rise) temperature target are the dire threat from sea-level rise, temperature
changes, and tropical cyclones that are already increasing measurably, and will do so even
more in a world beyond 1.5 ◦C [1]. One of the key findings of the Intergovernmental Panel
on Climate Change (IPCC) Special Report on Global Warming of 1.5 ◦C [2,3] is that the
world needs to be carbon-emissions neutral by 2050 or shortly thereafter. If this target is
taken as a guiding concept, roughly thirty years remain for most, if not all, countries to
decarbonize their energy systems; in a world largely free of fossil fuels, it will be critical for
SIDSs to accelerate this transition. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article
distributed
under
the
terms
and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/). Ocean energy technologies can help play a role in enabling island states to reach
targets of energy self-sufficiency [3,4]. Three basic, but linked ideas are behind the con-
tinued interest in ocean thermal energy conversion (OTEC) as an enabling technology in https://www.mdpi.com/journal/energies Energies 2021, 14, 2192. https://doi.org/10.3390/en14082192 Energies 2021, 14, 2192 2 of 19 particular [5–8]. First, as shares of increasingly economical variable renewable energy (VRE)
sources such as wind and solar photovoltaics are incorporated into the energy mix, there
will still be a need for dispatchable electricity sources to complement variability [9]. Sec-
ondly, much as with sun and wind, ocean energy as a primary resource is essentially infinite
and not depletable. Thirdly, OTEC can also provide extra services beyond the generation
of electricity, such as the desalination of water, cooling of buildings, and aquaculture [10]. y
g
g
q
In spite of these important driving factors and some continued interest in OTEC by
research groups and commercial ventures around the world, uptake has thus far been slow. Predictably, one of the valid reasons for the lack of adoption has been the relatively high
up-front cost that is expected for any emerging technology. 1. Introduction While batteries are increasingly an economically
viable option for backup [16,17], a balance between storage and dispatchable power will be
necessary, with consideration of the overall system-wide LCOE, not that of each technology
individually, being a more prudent way to view planning toward a 100% renewable energy
(RE) future. This is especially true in the context of SIDSs in the Caribbean, many of
which are just beginning transitions from a nearly complete reliance on oil and gas for
power generation, and thus have the opportunity for taking a longer-term systemic view
of power system transformation. The second strand of the economic argument is that the
combination of OTEC with auxiliary desalination as a combined system provides multiple
services; another potential benefit is the further combination of OTEC and desalination
with SWAC as an additional output that is of great added value on many islands which
continue to face increasing pressures owing to climate change [18]. The following subsections present a brief overview of the energy landscape in the
Caribbean region, linking resource and economic factors (Section 1.1). In Section 1.2, a
summary of various regional dispatchable RE resources is given, with an eye toward Energies 2021, 14, 2192 3 of 19 3 of 19 a transition to 100% RE. OTEC as a specific technology is presented in terms of both
physical and economic factors, including considerations of desalination and seawater air
conditioning as by-products (Section 1.3). Methodologies used in the mapping, economic,
and renewable energy integration analysis are presented in Section 2, leading to the results
described in Section 3. The filtering criteria (Section 2.1) are used in Section 3.1 for a
preliminary selection of potential Caribbean sites for OTEC based on GIS mapping of
bathymetry. In Section 3.2, the representative hourly demand and wind and solar data are
used to gain an understanding of the challenges of integrating high levels of VRE sources
into the power system, leading therefore to the necessity of complementary technologies
such as OTEC. Section 3.3 presents results for the levelized cost of electricity for the
integrated system for various combinations of renewable energy capacities together with
battery storage. Section 4 is a discussion of the results, and Section 5 provides some
conclusions concerning the adoption of OTEC for Caribbean SIDSs. 1.1. Status of Renewables across the Caribbean The abundance of unexploited renewable resources across the Caribbean positions
the region to become a leader in sustainable development. An overview of RE potential
across Caribbean Community (CARICOM) member states can be seen in Figure 1, with es-
timates for several renewable technologies based upon the 2027 energy capacity projections
outlined by the Caribbean Sustainable Energy Roadmap and Strategy [19]. For example,
the CARICOM subset of Eastern Caribbean islands from St. Kitts & Nevis to Grenada
collectively accounts for a potential of 6280 MW of exploitable geothermal power [19]. Interestingly, and although not currently planned, a collective approach to exploit this
resource could further increase its efficacy; for example, between the islands of St. Kitts
and Nevis (approximately 3.5 km from coast to coast), or between Dominica, Guadeloupe
and Martinique through inter-island grid connectivity [20]. On the other hand, geothermal
resources have been widely explored but often run into implementation difficulties and
delays (e.g., Grenada, Saint Lucia). Figure 1. Renewable energy distribution across the Caribbean Community (CARICOM) nations. Map created based on
data from Ochs et al. [19]. Figure 1. Renewable energy distribution across the Caribbean Community (CARICOM) nations. Map created based on
data from Ochs et al. [19]. Energies 2021, 14, 2192 4 of 19 It should be noted that SIDSs, in addition to their energy needs, are acutely focused
on climate adaptation measures that can be supported by ambitious RE integration plans. In the Caribbean, the primary focus will be on increasing penetration rates of solar photo-
voltaics and wind energy. The variable nature of wind and solar power mandates that there
be an additional source of energy or storage of energy to complement these two resources. Battery storage is an increasingly viable option for storing energy, whereby utilities operate
load shifting methods to “transfer” energy from times of plentiful sun and wind to those
times without [21]. The other available avenue to complement variable renewable power
generation is through the use of a dispatchable (controllable) source of power. If fossil
fuel sources and nuclear energy are not considered, a limited number of technologies are
available (e.g., hydropower, geothermal, biomass, waste, tidal, wave, and OTEC). Worldwide, hydropower has long been the dominant renewable electricity source;
however, hydropower plays a fairly insignificant role in the region (with few exceptions
such as Suriname and Belize, neither of which are part of the present analysis). 1.1. Status of Renewables across the Caribbean As shown in
the summary in Table 1 as well as in Figure 1, some countries have hydropower resources
that may be either very small (Grenada) or already at maximum capacity (Dominica and
St. Vincent and the Grenadines). In very few cases in the region, pumped hydropower
storage, and the increasingly viable conversion of renewable electricity to hydrogen through
hydrolysis are also being explored. Hydrogène de France (HDF), for instance, has recently
invested in developing a 55 MW/140 MWh hydrogen-based solar-plus-storage plant in
French Guiana in 2018 [22], for which work was expected to begin in 2020. Table 1. List of Caribbean countries with yes (green) or no (light red) filters for potential hydropower, geothermal and ocean
thermal energy conversion (OTEC) technologies as dispatchable renewable energy. For OTEC in this table, no filtering
has been done for resources to determine proximity to population centers or other infrastructure. In some cases (yellow),
hydropower resources may be small, either in absolute terms or in comparison to the overall system capacity. Additional
information for reference purposes on peak demand and electricity price by country, the latter adapted from NREL [23]. Table 1. List of Caribbean countries with yes (green) or no (light red) filters for potential hydropower, geothermal and ocean
thermal energy conversion (OTEC) technologies as dispatchable renewable energy. For OTEC in this table, no filtering
has been done for resources to determine proximity to population centers or other infrastructure. In some cases (yellow),
hydropower resources may be small, either in absolute terms or in comparison to the overall system capacity. Additional
information for reference purposes on peak demand and electricity price by country, the latter adapted from NREL [23]. Country
Hydropower
Geothermal
OTEC
Peak Demand
(MW)
Residential
Electricity Price
(USD/kWh)
Bahamas
308
0.32
Cuba
Turks and Caicos
34.7
0.26
Jamaica
644
0.28
Haiti
500
0.13
Dominican Republic
2506
0.13
Puerto Rico
3685
0.22
British Virgin Islands
32
0.24
U.S. Virgin Islands—St Thomas and St John
88
0.40
U.S. 1.1. Status of Renewables across the Caribbean Virgin Islands—St Croix
55
0.40
Anguilla
14
0.23
Sint-Maarten/Saint-Martin
42.6/32
0.30
St Kitts and Nevis
20.4 and 10.4
0.26
Antigua and Barbuda
50
0.40
Montserrat
2
0.50
Guadeloupe
254
0.19
Dominica
16.8
0.21
Martinique
235
0.11
St Lucia
60.3
0.28
St Vincent and the Grenadines
21
0.19
Barbados
168
0.25
Grenada
30
0.32
Trinidad and Tobago
1322
0.05
Bonaire
12
0.22
Curaçao
130
0.35
Aruba
135
0.17 Country
Hydropower
Geothermal
OTEC
Peak Demand
(MW)
Residential
Electricity Price
(USD/kWh)
Bahamas
308
0.32
Cuba
Turks and Caicos
34.7
0.26
Jamaica
644
0.28
Haiti
500
0.13
Dominican Republic
2506
0.13
Puerto Rico
3685
0.22
British Virgin Islands
32
0.24
U.S. Virgin Islands—St Thomas and St John
88
0.40
U.S. Virgin Islands—St Croix
55
0.40
Anguilla
14
0.23
Sint-Maarten/Saint-Martin
42.6/32
0.30
St Kitts and Nevis
20.4 and 10.4
0.26
Antigua and Barbuda
50
0.40
Montserrat
2
0.50
Guadeloupe
254
0.19
Dominica
16.8
0.21
Martinique
235
0.11
St Lucia
60.3
0.28
St Vincent and the Grenadines
21
0.19
Barbados
168
0.25
Grenada
30
0.32
Trinidad and Tobago
1322
0.05
Bonaire
12
0.22
Curaçao
130
0.35
Aruba
135
0.17 Energies 2021, 14, 2192 5 of 19 Another potential energy source, biomass use for power generation, can largely come
in two forms: either using waste from crops, such as sugar cane, or from purpose-grown
bioenergy crops. Biomass electricity can therefore play a niche role in some countries, but
especially on some of the smaller islands, a large biomass to electricity capacity is not to
be expected due to environmental concerns and climatic risks posed to already strained
agricultural systems. These limitations are further compounded by resource competition,
because most agri-based biomass systems need a constant supply of by-products which are
often more valuable on international markets than being converted into ethanol or burned
for electricity. y
Finally, waste-to-power generation could play a marginal role in some countries, either
from solid waste combustion or capture of landfill methane; although countries in the
region do have waste disposal challenges, the overall amount of waste generated in 2010
was ~1 kg/person/day) [24], with estimates of the combustion value and the resulting
electricity generation from municipal solid waste [25] leading to an energy production of
approximately 90 kWh/capita/year; a relatively small contribution compared to typical
island electricity consumption of ~2000 kWh/capita/year. 1.1. Status of Renewables across the Caribbean y
p
p
y
Beyond the critical issue of carbon emissions reductions, there are other reasons
for Caribbean SIDSs to transform their energy systems to domestic renewable resources. Caribbean member states are vulnerable to the volatile nature of the oil and gas industry;
hence, a continued reliance on fossil fuel imports hinders energy diversification and
economic security. Collectively, the average price of the domestic retail rate of electricity
across Caribbean islands states is ~USD 0.30/kWh [23]. Therefore, there is a continued
need for RE integration to mitigate trade imbalances due to fossil fuel imports. In addition,
Caribbean countries tend to rank in the middle of the Notre Dame Global Adaptation
Initiative Index [26], a measure of a country’s vulnerability to climate change and its
readiness to improve its resilience. The combination of vulnerability, economic stress and
climate change mitigation commitments motivate the present work. Ocean energy technologies such as wave, tidal and OTEC are not represented in
Figure 1. Of these, the first two have very low potential in the Caribbean [4], whereas
OTEC has much more favorable potential in some localized areas. In the next subsection,
the available dispatchable RE technologies in the region are explored in more detail,
assuming that solar PV and wind will form the backbone of the power system. 1.3. OTEC, SWAC and Desalination 1.3. OTEC, SWAC and Desalination OTEC, a concept that has been around for over a century, takes advantage of the
temperature difference between warm surface ocean water and constant temperature
deep ocean water; typically, the difference is ~20 ◦C for useful energy harvesting to
drive a thermodynamic engine cycle [3]. At depths of approximately 1000 m, ocean
temperatures are nearly uniformly at ~4 ◦C. For a temperature difference of 20 ◦C and
constant year-round availability, low-latitude regions are most promising, with surface
water temperatures of 25 ◦C or more [3]. The approach of OTEC is to take advantage
of effectively infinite hot and cold reservoirs with a small temperature difference, and
therefore low thermodynamic efficiency, but with a resource base that is theoretically
inexhaustible given the persistent thermal gradients. There are three main strands of literature concerning OTEC and the related technolo-
gies. A series of papers has initially mapped global, and some regional, potentials based
on sea-surface temperatures [7,27] In addition, whether for OTEC, SWAC or desalination
work, analyses of bathymetry have been undertaken to a somewhat lesser degree [28]. Sections 2.1 and 3.1 of this paper explore regional variations in more detail, which is one of
the main contributions of this work. The second and larger area of research is focused on the thermodynamic efficiency and
optimization of technological system components for OTEC, usually with much less or no
attention given to the geographical location of the potential systems. Two main categories
of OTEC are the closed-cycle (CC) and open-cycle (OC) OTEC systems. CC-OTEC uses a
high vapor pressure working fluid together with heat exchangers where the warm surface
ocean water vaporizes the fluid, which then drives a turbine and a generator. The fluid
condenses when coming in contact with the cold reservoir, water coming from the deep
ocean. OC-OTEC, on the other hand, takes warm surface water and draws it into a low-
pressure chamber in which it is flash evaporated (boiled) which drives a low-pressure
turbine and subsequently the generator. Here, the condensed water resulting from heat-
exchanger contact with the colder, deep-ocean water, is also desalinated in the process, a
co-benefit of this process cycle [29–39]. p
y
For both processes, there is potential for using the circulating cold water for SWAC,
essentially a low-carbon and low-cost replacement for utility-scaled and chiller-based
cooling. 1.3. OTEC, SWAC and Desalination However, in all of these technologies, two of the most critical and expensive
components are the heat exchangers and the necessary piping to reach deep, cold ocean
water, and subsequently, coastlines. Having both warm and cold-water reservoirs near
the generation facility and for SWAC, near-demand for cooling becomes one of the most
important criterion for site selection [28]. The third area of research, usually in conjunction with one of the first two, is to
analyze the economic feasibility, or at least, the system costs of OTEC, desalination, and
accompanying SWAC outputs. Sections 2.2 and 3.3 explore these aspects in more detail,
highlighting the main economic considerations where the emphasis is placed on the
economics of both OC- and CC-OTEC, showing that costs decrease when moving to
the CC-OTEC technology, due in part to the overall larger size (>10 MW) of these systems
compared to smaller OC-OTEC plants [6,8,10,29,40,41]. 2. Materials and Methods The following three sections present the methodologies used in this paper. Bathymetry
mapping of all Caribbean Island states was used to determine the most promising sites
for OTEC (Section 2.1). A summary of economic parameters and approaches is given in
Section 2.2. The description of residual loads and the hourly modeling of RE generation
and battery storage is provided in Section 2.3. 1.2. Summary of Dispatchable Renewable Technologies and OTEC Potential The analysis presented in this paper is multi-faceted, looking at OTEC resource poten-
tial in all Caribbean island states, some ancillary advantages of OTEC as both a supporting
technology for variable renewable systems as well as in terms of seawater desalination as
an additional adaptation and resilience measure, and finally, at the economics of OTEC as
part of a 100% RE system. The International Renewable Energy Agency (IRENA) surveyed
ocean energy resources around the world [4], and for the Caribbean region, both tidal and
wave power are poor resources due to limited tidal channels to harness energy; therefore,
these technologies are not considered within this study. Table 1 gives a summary of po-
tential resources for hydropower, geothermal and OTEC, summarizing the discussion in
the previous section and with the latter based on the results to be shown in Section 3. The
comparison is then used to motivate the results of this paper and look in more detail at
OTEC as a potentially viable and alternative complementary power source for high VRE
penetration, and as a technology that can also provide other co-benefits for those regions
in which it is viable. Geothermal and OTEC as listed are really either available or not,
depending on geological conditions. Hydropower in some cases may be available on a
small scale, either in absolute terms or relative to system size. In addition, peak demand for
each of the islands is listed to provide a sense of the system size [23]. This will become more
relevant in the discussion below on complementing VRE with dispatchable renewables. Energies 2021, 14, 2192 6 of 19 2.1. GIS Bathymetry Mapping of the Caribbean Region Previous low-resolution mapping of potential OTEC resources that looked at sites
with a temperature difference ~20 ◦C and within 200 miles of coastlines [15] is expanded Energies 2021, 14, 2192 7 of 19 upon in the present work. Suitable locations within the Caribbean region, with an emphasis
on SWAC, have also been previously investigated [40]. A very recent report explored a
specific site in Puerto Rico in great detail, and represents the follow-up stage for any given
sites identified here [42]. The main requirements applied in what follows are having a depth of 1000 m, for con-
sistent ~4 ◦C temperature, and that potential OTEC sites be near coastal areas to minimize
piping lengths and allow land-based infrastructure for the OTEC power plant. Coast-
lines were defined using the National Oceanographic and Atmospheric Administration
(NOAA) high-resolution shoreline database, and then extended out to a distance of 10 km. The primary bathymetry dataset used was the General Bathymetric Chart of the Oceans
(GEBCO) [43], which covers the complete extent of the study area at a 15 arc-second resolu-
tion. Information on bathymetric source data types is provided with the downloaded grid,
with examples including single and multibeam bathymetry, and seismic and sounding
surveys. The 10 km study area extending from coastlines was further refined with 2.5 km
shoreline buffer increments symbolized to emphasize proximity to the coast. Particular
areas of interest within the study area were located by identifying the gridded areas of the
GEBCO bathymetry dataset at depths greater than 1000 m. Over the extent of the study
area, the horizontal resolution of the GEBCO 15 arc-second depth data was approximately
400 m (range 385–460 m). g
For purposes of organization, two sub-regions within the Caribbean region are con-
sidered (Figure 1). The Greater Antilles consisting of larger islands such as Cuba, Jamaica,
Hispaniola (Haiti and the Dominican Republic), and Puerto Rico; The Bahamas and Turks
and Caicos Islands are also taken as part of this group. The Lesser Antilles are the islands
ranging from the U.S. and the British Virgin Islands and Anguilla southward to Trinidad
and Tobago, including Barbados and islands near the coast of South America (Aruba,
Curaçao, Bonaire and Isla de los Roques). Each of these is examined in turn to identify
candidate areas within these regions for OTEC implementation based on the chosen criteria. 2.1. GIS Bathymetry Mapping of the Caribbean Region Detailed maps of the bathymetry and distances to the coast for all islands are shown stati-
cally in the Supplementary Information online as well as being available as an interactive
mapping tool at https://tinyurl.com/8hkznwxr (accessed on 13 April 2021). 2.2. Summary of Economic Parameters for OTEC and Desalination As referenced above, a number of studies have attempted to determine the costs
for coupled OTEC and desalination and SWAC systems. The typical view as been that
(i) these technologies are not yet ripe, (both technologically and economically), being only
in the pilot-project stage, but that (ii) with enough research and deployment, economies of
scale will drive costs down, with one of the reasons for examining the feasibility of these
coupled systems stemming from the hope for better energy economics with these dual-use
technologies. However, as shown by the specific cases highlighted here with the filtering
of likely areas for OTEC, the feasible sites dwindle in number to very few. y
y
Relatively few detailed economic estimates are available in the literature. The most
complete recent accounting for costs is for a CC-OTEC system [29]. A detailed study of
both CC and OC systems was carried out in Vega [8]. In this paper, the large degree of
uncertainty in OTEC cost estimates is recognized, but literature results are used to guide
the analysis. Earlier work assumed an offshore platform for hosting the OTEC system, with
the platform, moorings and undersea power cable representing a significant fraction of
the total cost. These previous analyses also assumed a relatively large, generically placed
(geographically) OTEC plant of 50 MW capacity, having determined that a strong cost
advantage arises in moving from plants of 10 MW or less to this larger size due to scale
effects [8]. For the proposed applications discussed in the present work, smaller plants
or units in the order of 5–10 MW capacity are more appropriate. Based on Vega [8], the
specific (i.e., per kW of capacity) capital cost of a 5–10 MW plant would be approximately
three times that of a 50 MW plant [8]. One key assumption, following Vega [8], is that
overall component costs for the CC and OC plants will be approximately equal [8]. Using Energies 2021, 14, 2192 8 of 19 these scaling factors and assumptions, the capital cost for a 5 MW OC-OTEC plant would
be approximately USD 13,500/kW (also converting 2009 USD to 2018 USD with a producer
price index factor of 1.2). A more recent analysis examined an OC-OTEC plant with a net capacity of 2.3 MW
(after self-consumption was taken into consideration) in which multiple such units could
be combined for a power plant of larger total capacity [29]. 2.2. Summary of Economic Parameters for OTEC and Desalination Those authors estimated a
levelized cost of electricity of EUR 269/MWh (~USD 300/MWh or USD 0.30/kWh) in
their base case, with a capital cost of EUR 16,000/kW (EUR 14,000/kW in a low-cost case). Finally, another recent paper estimated capital costs for a 10 MW OC-OTEC system to be
USD 15,000/kW [44]. This result is somewhat higher than that of the earlier work [8], but
within any reasonable estimate of uncertainty and will be used as a best-estimate baseline
in the analysis, with sensitivity tests for lower and higher costs being applied. y
y
g
g pp
As far as the production of desalinated water and electricity is concerned, an estimate
gives daily production of 118,000 m3 and an annual output of electricity (assuming an
overall 92% capacity factor) of 414,415 MWh [8]. For operation of a smaller system with
0.5 MW net capacity and 80% capacity factor, a freshwater production of 1175 m3/day was
found in Kim et al. [33], in very good agreement with Vega [8]. More realistically, especially
given the grid integration potential considered here, a capacity factor of ~70% should
be taken if sized reasonably for the system, which increases the LCOE. This co-benefit
of desalinated water will be considered in the analysis as well. Estimating the cost of
water from an informal survey of the websites of regional water agencies, a value of USD
1.5/m3 was used and sensitivity to lower (USD 1/m3) and higher (USD 2/m3) water prices
was tested. 2.3. Load, Residual Load and System Benefits of Dispatchable Renewable Energy With these three datasets, each of which can be scaled in amplitude to represent different Energies 2021, 14, 2192 9 of 19 9 of 19 levels of production of wind and solar power, as well as for different overall demand, an
hourly time series can be constructed that shows the residual load after VRE has been taken
into account, i.e., load minus solar and wind power. For an assumed installed capacity
of a dispatchable source (OTEC is the assumed technology in this case, but this could be
made up of different sources), if the residual load from VRE is positive, i.e., demand is not
satisfied, then the dispatchable source is used to fill in the gap up to its maximum capacity. In the model, the dispatchable source is also assumed to have a minimum output that is
chosen to be 25% of the maximum capacity. Finally, storage is integrated into the model
with a given capacity (MWh) and power output (MW) (batteries, either at utility-scale or in
an integrated grid with electric vehicles, or perhaps hydrogen with fuel cells), such that
an oversupply of VRE can charge the storage, or undersupply of VRE with dispatchable
source results in the discharge of energy storage; the dispatchable renewable source can
also be used to charge the battery up to its maximum capacity as needed. This process is
modeled for each hour of the year with the goal of satisfying demand at each hour while
keeping track as well of the capacity factor of the dispatchable source, the state of charge
of the storage, and the total curtailed amount of VRE during the year. A convenient way
to visualize the various trade-offs that arise, including that of meeting demand versus
curtailing VRE (which can in some cases be part of an optimal solution) is through the
use of residual load duration curves [57]; this approach is presented in the Supplementary
Information online. A variety of combinations of dispatchable renewable source, storage capacity, and
VRE (wind + solar PV) can meet the demand for all hours of the year. Using this model, it
is possible to find the amount of storage (in MWh) needed for a given combination of wind,
solar PV, and dispatchable renewable power (e.g., OTEC) capacities such that demand for
all hours of the year is met. 2.3. Load, Residual Load and System Benefits of Dispatchable Renewable Energy According to the best available science as summarized by the IPCC, compliance
with the Paris Agreement will require a near-total phase-out of fossil fuels by about
2050 globally [2]. In support of the need to understand this transition, modeling integrated
systems of 100% RE has become an increasingly active field of research [45–48]. The strong
decrease in the past decade in the cost of solar PV, wind power and batteries, and in the
near future, of electric vehicles, outlines a pathway forward to the elimination of fossil
fuels and reliance on sustainable, renewable sources of energy [16,49–51]. gy
In general, there is a trade-off between the possibility of integrating high percentages
of variable renewables and the use of either storage or a dispatchable power source. As
will be shown, adding a relatively small amount of dispatchable capacity, even if expensive
when considered in isolation, can enable a significantly increased uptake in much cheaper
wind and solar energy. Thus, when an overall system LCOE is considered, there can still
be a benefit of the apparently expensive technology [52,53]. To investigate trade-offs, a Python-based model was constructed (available at https:
//github.com/RJBrecha/OTEC-Caribbean, accessed on 13 April 2021), and a fictitious
but representative Caribbean island was assumed, with a yearly electricity generation
of 250 GWh and a peak demand of 37 MW. Here, proprietary hourly demand data have
been used, but scaled from an actual country to the total generation for this fictitious
island. Load curves tend to be very similar for smaller Caribbean islands except for
the overall amplitude, and at the level needed for this demonstration of principle, these
data are deemed sufficient. Hourly demand data can alternatively be taken from data
available for synthetic demand curves generated as part of 100% RE modeling efforts [54];
comparison with real data shows a somewhat exaggerated secondary evening peak for the
synthetic data. To a first approximation, solar and wind energy generation at an hourly time resolution
for a given modeled installed capacity can be obtained from https://www.renewables. ninja/ (accessed on 13 April 2021) based on reanalysis data [55,56]; before embarking on a
large-scale transformation it would be necessary to undertake actual in situ measurements. 2.3. Load, Residual Load and System Benefits of Dispatchable Renewable Energy Table 2 summarizes input parameters and assumptions used
for the scenarios and to determine the total system levelized cost of electricity (sLCOE). Whereas the exact nature of the dispatchable source is of less importance here, for several
of the Caribbean islands under consideration, OTEC may be the best or only dispatchable
renewable technology potentially available. Indicative costs are based on storage and
renewable energy costs [51,58,59]. Table 2. Parameters for the evaluation of system levelized costs of electricity (sLCOE) for different
combinations of solar photovoltaic (PV), wind, dispatchable renewable and storage. Table 2. Parameters for the evaluation of system levelized costs of electricity (sLCOE) for different
combinations of solar photovoltaic (PV), wind, dispatchable renewable and storage. Peak power
37.7
MW
Yearly energy
250
GWh
Levelized cost of wind
USD 100
/MWh
Levelized cost of solar PV
USD 100
/MWh
Levelized cost of dispatchable
renewable source (OTEC)
USD 300
/MWh
Levelized cost of storage
USD 300
/MWh
Lifetime of storage
15
years
Lifetime of system
20
years With these data and parameters as background, the main results of this paper are
presented in the following section. 3. Results 3. Results Results are presented in the following three subsections. First, examples of the results
of GIS mapping for near-shore OTEC potential are given in Section 3.1 with more details
in the Supplementary Information. System integration of variable and dispatchable re-
newables with battery storage are shown in Section 3.2 and example system LCOE results Energies 2021, 14, 2192 10 of 19 10 of 19 are given in Section 3.3 showing estimated costs both with and without the inclusion
of desalination. are given in Section 3.3 showing estimated costs both with and without the inclusion
of desalination. 3.1. GIS Mapping of Deep Water at Different Distances from the Coast 3.1. GIS Mapping of Deep Water at Different Distances from the Coast Example results of GIS bathymetry and coastal distance mapping are shown in the
following two sections for the Greater and Lesser Antilles; a summary of promising
locations for OTEC near towns or other facilities is shown in the final subsection. 3.1.1. Greater Antilles (with The Bahamas and Turks and Caicos) As an example, a map of Jamaica is shown in Figure 2. On this map, the blue area
shows the regions of >1000 m depth, and the gray area those with depth <1000 m. The
additional contours are for distances of 2.5 km (green), 5.0 km (yellow), 7.5 km (orange)
and 10 km (red) from the coast. The interpretation of the map is that any area for which
the blue 1000 m depth contour is closer to the coast than a given distance contour will
represent cold, deep water at a constant temperature. For the sake of the evaluation, the
most promising locations are those closer than 5 km (yellow line) and preferably (in the
sense of the cost of construction) closer. In the case of Jamaica, the best locations from the
point of view of a near-coastal resource for OTEC would be near Negril, Lucea, southeast
of Kingston, and near Port Maria and Port Antonio in the northeast. A more detailed list of
potential sites in the Greater Antilles is given in Table 3. Table 3. List of sites with OTEC potential (1000 m depth at closer than 5 km to the coast) as well as
being near towns or other infrastructure. Jamaica
Western
Negril (hotels, airport)
Northwestern
Lucea
Northwestern
Montego Bay
Southeast
East of Kingston
Grand Cayman
All areas
George Town, Bodden Town, East End, West Bay
Cuba
Southeast
Santiago de Cuba
Northeast
Guardalavaca (tourist resorts)
Northeast
Playa Uvero, Playa La Playita (tourist resorts)
Northeast
Havana
Bahamas
Central
Nassau
Turks and Caicos Islands
East
Cockburn Town
Haiti
West
Canal de St.-Marc, Canal de la Gonâve
Dominican Republic
South
Barahona, Paraíso, Los Patos
Puerto Rico
Southeast
Guayama
Guadeloupe
Northeast
Le Moule
Dominica
West coast
Roseau, Portsmouth
Martinique
West coast
Fort-de-France, St Pierre
St Lucia
Southwest
Soufriére
St Vincent and the
Grenadines
West coast
Kingstown Table 3. List of sites with OTEC potential (1000 m depth at closer than 5 km to the coast) as well as
being near towns or other infrastructure. 11 of 19 Energies 2021, 14, 2192 Figure 2. 3.1. GIS Mapping of Deep Water at Different Distances from the Coast Map of Jamaica with a bathymetry contour representing the boundary between depths of greater than 1000 m
(blue) and less than 1000 m (gray). Other contours are equidistant from the coast at 2.5 km (green), 5.0 km (yellow), 7.5 km
(orange) and 10 km (red). Figure 2. Map of Jamaica with a bathymetry contour representing the boundary between depths of greater than 1000 m
(blue) and less than 1000 m (gray). Other contours are equidistant from the coast at 2.5 km (green), 5.0 km (yellow), 7.5 km
(orange) and 10 km (red). 3.1.2. Lesser Antilles Two examples of islands with promising OTEC locations for the Lesser Antilles are
shown as examples in Figure 3, for Martinique and for Saint Lucia. Several of the Eastern
Caribbean islands have deep water within 10 km of the coast. Again, the areas enclosed
in red are distances of 10 km and distances from the coast of 5 km are shown in yellow. Depths of 1000 m and greater are outside (i.e., farther from the coast than) the gray area and
represented in blue. It can be observed that several areas off the coasts of islands appear to
be viable sites for OTEC, with deep, cold ocean water at distances of 2.5–5 km or less. A
more detailed summary of mapping and potential sites is shown in the SI online, but also
explicitly includes those islands with no likely OTEC potential according to these criteria,
for example, St. Kitts and Nevis, Antigua and Barbuda, Aruba and Trinidad and Tobago. As an additional example of an island without potential OTEC resources according
to the criteria that have been set here, in Figure 4 a map of Antigua is shown in the same
format. The gray area is at depths of less than 1000 m, and the contours out to 10 km and
beyond all lie within that relatively shallow area. Thus, to reach sufficient depths around
Antigua for OTEC, there would have to either be very long pipes, or the system would
have to be set up on a floating platform. The area off the northeast coast of Antigua, nearest
to the deep water, also encompasses a Marine Protected Area, which would present an
additional hurdle to implementation and represent a potentially negative impact in the
broader sense of sustainability for energy system infrastructure. 12 of 19 12 of 19 Energies 2021, 14, 2192 Figure 3. Maps of two example countries in the Lesser Antilles, (a) Martinique and (b) Saint Lucia. Bathymetry contour
(gray/blue) represents the boundary between depths of greater than and less than 1000 m. Other contours are equidistant
from the coast at 2.5 km (green), 5.0 km (yellow), 7.5 km (orange) and 10 km (red). Figure 3. Maps of two example countries in the Lesser Antilles, (a) Martinique and (b) Saint Lucia. Bathymetry contour
(gray/blue) represents the boundary between depths of greater than and less than 1000 m. 3.1.3. Summary of Promising OTEC Sites 3.1.3. Summary of Promising OTEC Sites While this study provides a more detailed mapping analysis than has been previously
published, precise evaluation of potential projects will rely on a number of additional
important details, such as the presence of Marine Protected Areas coincident with near-
shore deep water, the location of towns or tourist areas, as well as convenient roads and
transmission infrastructure. As a first approximation, only areas that were within the 5 km
buffer were chosen, and also near infrastructure as described. Thus, the results presented
in Table 3 are not exhaustive, but rather provide examples of potential sites for OTEC. At
this first level of approximation, several islands can fulfill this latter criterion as well. For
example, Dominica (near the capital city Roseau), the west coast of Martinique, and St. Lucia (near Soufrière) are among the most promising sites, along with several areas in
Cuba and Jamaica, amongst others. g
Below OTEC capacities of 10–25 MW will be considered; this amount of capacity can
have the greatest impact in terms of energy generation across the islands with smaller
overall power capacity (as shown in Table 1), notably, the islands of Dominica, St. Vincent
and the Grenadines, Saint Lucia, and Grenada. Of the larger islands, Jamaica in particular
is aggressively pursuing increased rates of RE penetration and could potentially adopt
OTEC technology to supplement the intermittent nature of the dominant renewables of
solar and wind. Islands such as Grenada and Saint Lucia have long included geothermal
technology with capacities of 10–30 MW in their energy system planning, but have had
challenges in seeing these plans come to fruition; OTEC could be an alternative and these
islands (together with others) and the potential OTEC locations are summarized in Table 3. 3.2. Results for Balancing Dispatchable OTEC Technology with Variable Renewables and
Battery Storage In Figure 5, two cases are shown in which the dispatchable OTEC technology capacity
is set at 10 MW (Figure 5a) and at 20 MW (Figure 5b), and the capacities of the VRE tech-
nologies are varied from 0 to 200 or 100 MW (x- and y-axes). The amount of storage capacity
is capped here at 2000 MWh and at 1000 MWh, respectively, for clarity of presentation. 3.1.3. Summary of Promising OTEC Sites The
main point to note is the relationship between a decrease in dispatchable power capacity
and an increase in necessary storage capacity, becoming more pronounced at lower wind
and solar PV capacities. Essentially, for low dispatchable capacity, large amounts of storage
are needed, mainly to make up for a relatively small number of extended periods during
which wind and solar PV power are both not available. In Figure 5, there is a very sharp
rise in battery capacity at low levels of wind and solar capacity; this feature is an artefact of
the problem definition and represents the fact that not enough overall capacity is available
in the system to cover demand during a significant period of time during the year. Table 4 shows the results for a selection of cases with differing amounts of VRE and
dispatchable RE, effectively representing points on the surface of the plots in Figure 5 when
combined with the storage capacities. One feature not visible in Figure 5 is the amount
of curtailed variable renewable power, which becomes significant as the VRE capacity
increases, and thus represents an additional trade-off to be considered. Table 4 shows the
curtailment amount in GWh per year for each selected case. The combination of all these
factors contributes to the total system cost. 3.1.2. Lesser Antilles Other contours are equidistant
from the coast at 2.5 km (green), 5.0 km (yellow), 7.5 km (orange) and 10 km (red). Figure 4. Map of Antigua with bathymetry contours and the blue area representing depths of greater
than 1000 m and gray for less than 1000 m. Other contours are equidistant from the coast at 2.5 km
(green), 5.0 km (yellow), 7.5 km (orange) and 10 km (red). Marine protected areas are shown within
the light green polygons. Figure 4. Map of Antigua with bathymetry contours and the blue area representing depths of greater
than 1000 m and gray for less than 1000 m. Other contours are equidistant from the coast at 2.5 km
(green), 5.0 km (yellow), 7.5 km (orange) and 10 km (red). Marine protected areas are shown within
the light green polygons. Figure 4. Map of Antigua with bathymetry contours and the blue area representing depths of greater
than 1000 m and gray for less than 1000 m. Other contours are equidistant from the coast at 2.5 km
(green), 5.0 km (yellow), 7.5 km (orange) and 10 km (red). Marine protected areas are shown within
the light green polygons. Energies 2021, 14, 2192 13 of 19 13 of 19 3.3. Results for System Levelized Cost of Energy Table 4 also shows the sLCOE for each of the eight cases. In Figure 6a, a further
comparison is made for these eight cases, with the blue and orange bars representing the
sLCOE both without and with the inclusion of benefits of desalinated water that would be
produced by an OC-OTEC system. Additionally, displayed in Figure 6 is a shaded region
that represents the estimated LCOE for a diesel reciprocating engine system that has, until
recently, been the power source of choice for many countries [51]. One feature not included
here is costs incurred due to grid extensions and other system costs often associated with the
higher penetration of renewables [60]. These costs will be very dependent on individual Energies 2021, 14, 2192 14 of 19 14 of 19 system configurations and would require further investigation within the context of a
given country. system configurations and would require further investigation within the context of a
given country. Figure 5. Necessary amount of storage capacity (in MWh) to allow demand to be satisfied for every hour of the year, and as
a function of the installed wind and solar PV capacity. (a) With 10 MW of dispatchable renewable capacity and (b) with 20
MW of dispatchable renewable capacity. Peak system demand is 37 MW in this example. Note the difference in scale of a
factor of two between the plots. Figure 5. Necessary amount of storage capacity (in MWh) to allow demand to be satisfied for every hour of the year, and as
a function of the installed wind and solar PV capacity. (a) With 10 MW of dispatchable renewable capacity and (b) with 20
MW of dispatchable renewable capacity. Peak system demand is 37 MW in this example. Note the difference in scale of a
factor of two between the plots. Table 4. Sample results for sLCOE (USD/MWh) for different system configurations (solar PV, wind, dispatchable renewable,
storage). Comparison is made with and without including the co-benefit of desalination. Dispatchable (Disp.); Desalination
(Desal.); Curtailment (Curtail.) For the sLCOE with desalinated water, sensitivity to water price is included in parentheses,
with the base case being USD 1.5/m3 and in the range USD 1/m3 to USD 2/m3. Case
Solar
(MW)
Solar
(GWh)
Wind
(MW)
Wind
(GWh)
Disp. RE
(OTEC)
(MW)
Disp. RE
(OTEC)
(GWh)
Storage
Capacity
(MWh)
Energy from
Storage
(GWh)
Curtail. (%)
sLCOE
(USD/MWh)
With Desal. 3.3. Results for System Levelized Cost of Energy Water
(USD/MWh)
1
200
335
73
204
0
0
2000
42.5
53
424
424
2
140
234
73
204
10
40
1000
17.8
48
326
300 (292, 309)
3
120
201
53
150
10
46
1500
24.5
37
351
322 (313, 332)
4
100
167
44
122
15
71
1000
15.8
30
304
259 (244, 274)
5
90
151
34
95
15
79
1500
20.3
23
349
3299 (283, 316)
6
80
134
17
48
20
117
1000
15.7
16
316
242 (218, 267)
7
90
151
24
68
20
108
500
11.3
23
267
199 (177, 222)
8
60
100
29
82
25
115
200
2.37
16
229
156 (133,181 There are several points to note about these summary results. Firstly, costs for solar
and wind have been set at USD 100/MWh; a conservative estimate in that there are many
examples around the world of far lower LCOE for these technologies, and in fact in more
mature markets, power purchase agreements have been tendered with costs of only USD
30–40/MWh for systems of solar PV or wind energy, even including battery storage in
some cases. On the other hand, Caribbean islands have not yet shown the cost decreases
to these lowest levels. A second point is to emphasize that USD 300/MWh is used to
represent relatively untested OTEC costs; with other technologies such as geothermal
or hydropower, the dispatchable source would be expected to have significantly lower
LCOE, thus lowering the sLCOE cost with respect to those shown here, even without the
added benefit of desalinated water, as illustrated in Figure 6. Even with these caveats and
relatively conservative assumptions, the system LCOE for OTEC with the co-benefit of Energies 2021, 14, 2192 15 of 19 15 of 19 desalinated water, and in some scenarios even without this advantage, is less than it would
be for diesel power generation. To represent potential and likely future developments, Figure 6b shows the same
analysis but with an assumed cost of solar PV and wind each of USD 50/MWh, and
storage costs of USD 150/kWh, keeping the uncertain cost of the dispatchable OTEC
source constant at USD 300/MWh. This situation might represent expected costs by 2030,
which is when many Caribbean islands will have increased the implementation of variable
renewables and will be looking at options for complementing variable renewables with
a dispatchable source of RE. 3.3. Results for System Levelized Cost of Energy It is seen that with these costs decreasing, even with the
relatively expensive OTEC technology as a backstop, the total system cost of electricity
is less than what would be expected for diesel generators in nearly all cases. Taking into
account the added benefit of desalinated water, the difference is even larger. Figure 6. Comparison of the sLCOE for eight example cases as described in the text and in Table 4: (a) with estimated
current costs of each technology, and (b) with estimated costs in 2030, when deep renewable energy penetration will likely
be starting to make dispatchable technologies a necessity to complement variable renewable energy sources. Figure 6. Comparison of the sLCOE for eight example cases as described in the text and in Table 4: (a) with estimated
current costs of each technology, and (b) with estimated costs in 2030, when deep renewable energy penetration will likely
be starting to make dispatchable technologies a necessity to complement variable renewable energy sources. 4. Discussion OTEC has been presented here as a potential niche solution for high-penetration
renewable energy systems in Caribbean island countries. OTEC has been in discussion as a
power source, together with co-benefits such as seawater air conditioning and desalination,
for many decades. The principles of OTEC are well known, but in many situations there are
other technologies with better prognoses for large-scale adoption. However, as described
here, for island nations with large amounts of solar and wind energy potential, either
energy storage or a dispatchable energy resource is necessary as a complement to variable
renewables. Many studies have looked at OTEC, focusing on the technology itself and
understanding how to make OTEC more economically competitive. In the present work,
a different starting point has been taken, namely, that of considering OTEC as one part
of a system and looking at the advantages of even a relatively expensive (in the sense of
LCOE) technology in enabling a higher penetration of inexpensive variable renewables. The key is then to look at the electricity system as a whole and not at each technology
independently—the system LCOE is the important parameter, and OTEC can contribute to
a system with an economically competitive LCOE dominated by solar and wind. OTEC technologies present many challenges, mostly infrastructural, both because
they are relatively untested on a larger scale and due to the partial location of structures
in ocean waters. Caribbean systems are particularly vulnerable to extremes in weather Energies 2021, 14, 2192 16 of 19 owing to the pronounced hurricane season and deep convective atmospheric conditions
that often result in storm surges and inclement weather during the rainy seasons. owing to the pronounced hurricane season and deep convective atmospheric conditions
that often result in storm surges and inclement weather during the rainy seasons. OTEC systems are governed by basic principles of vertical ocean thermal gradients
and are relatively simple in their operation, excluding more advanced hybrid and electrol-
ysis complementary operations. Both floating and shelf- or land-based systems involve
extensive lengths of piping which can be easily disrupted by turbulent ocean surfaces. Here, the focus has been on land-based systems because the foreseen application is that of
a dispatchable power source that complements variable wind and solar PV, and therefore
provides an important stabilization role in the grid for which risks of disruption should be
minimized. 4. Discussion Although having these systems at some distance offshore would provide the
advantage of tapping into greater and less variable thermal gradients, this would come
at a greater infrastructural cost and capital risk. The Caribbean basin is already seeing
more weather extremes in recent years, and meteorologists have shown through extensive
climate models that climate change is making hurricanes more frequent and powerful over
the Atlantic Ocean, where they eventually cross the Caribbean Sea via various paths. In
a recent extreme example, the 2017 hurricane season cost Caribbean countries and the
United States USD 200 billion, with Harvey, Irma, María and José leaving islands such as
Barbuda, Dominica and Puerto Rico completely incapacitated by their passage [61]. Thus,
sea-based OTEC systems are considerably more vulnerable to these climatic changes given
their operation and offshore siting. The increased variability in the tracks of hurricanes
is also adding new challenges for the region when viewed in the light that new countries
and economies, once at low risk to these systems (Guyana and Trinidad and Tobago for
instance), may become increasingly vulnerable to these weather extremes. 5. Conclusions In this work, a set of observations relevant to achieving the challenging goal of
100% renewable energy systems in the Caribbean Island States has been presented. By
their very nature, these countries and territories have limitations in both resources and
interconnections that would otherwise ease the transition to fossil-free energy systems. gy y
The positive side of this scenario of transformation is that Caribbean islands are
wealthy in the inexhaustible natural resources of solar and wind power; however, dispatch-
able RE resources are more unevenly distributed among islands, even within a small region. While there has been a dramatic reduction in the cost of wind turbines and solar PV panels
over the past decade, bringing the cost of these technologies to a level competitive with the
existing fossil-fuel generation used by most Caribbean islands, the same is not necessarily
true for other renewable resources such as geothermal power and ocean technologies such
as OTEC and wave power. In power systems dominated by variable renewable sources,
complementary technologies are necessary to ensure grid reliability. As has been shown
here, there is a significant tradeoff in islanded systems between the availability of storage
and dispatchable renewable resources. Implementation of an OTEC system with a capacity
in the order of several MW for a system with a peak demand of a few tens of MW serves to
significantly reduce the battery storage capacity necessary for satisfying hourly demand
throughout a representative year. OTEC itself is unique in that it can provide more than
just electricity services, i.e., desalination and seawater air-conditioning (only mentioned
here), each of which can help make the system costs more favorable. There remains the crucial question of up-front capital costs, which would be relevant
one way or another as fossil-fuel generation capacity will be either replaced or phased out
with increasing pressure in the coming decade. Oil-based power generation will certainly
remain as one option; however, given the cost advantages of RE, there is also the increased
risk of new investments either becoming stranded assets or that they will block investment
in RE. As has been shown, there are various options on different islands for complementing
the wealth of solar and wind potential with other technologies, including OTEC. 5. Conclusions In the
end, a tradeoff exists between the relatively higher capital costs of wind and solar, followed
by near-zero operating costs, versus the lower and more familiar cost of purchasing diesel Energies 2021, 14, 2192 17 of 19 17 of 19 engines that are then accompanied by high yearly fuel and operating costs. Detailed energy
system planning will be necessary to demonstrate the lifecycle benefits of renewables, but
financial resources must also then be made available to set countries down the pathway
to renewables. Long-term system planning will also be necessary for each island to take advantage of
its domestic resources; 100% RE systems are feasible but having some fraction of the system
capacity in the form of a dispatchable resource is advantageous, and some islands are
strong candidates for the implementation of OTEC as a supporting technology. There are
challenges to rebuilding energy systems, whether in the Caribbean or elsewhere. Islands in
tropical regions offer large hurdles but also significant advantages, and are opportunities to
serve as models for how to diverge from a business-as-usual path of fossil-fuel dependence
and move toward a sustainable, renewable energy future. Supplementary Materials: The following are available online at https://www.mdpi.com/article/
10.3390/en14082192/s1, Part I—GIS mapping details and procedure outline; Part II—Additional
results of mapping and preliminary site selection; Part III—Residual load duration curves for the
visualization of hourly supply and demand. Author Contributions: R.J.B. conceptualized the research and developed the hourly demand and
supply model. K.S. performed the GIS mapping. M.A. and R.K.K. provided regional expertise
and input to the framing of the manuscript. R.J.B. drafted the manuscript; R.J.B., M.A. and R.K.K. edited and revised the manuscript. All authors have read and agreed to the published version of
the manuscript. Funding: This research was funded for R.J.B. by the EU Horizon2020 Marie-Curie Fellowship
Program (H2020-MSCA-IF-2018, proposal number 838667—INTERACTION. Institutional Review Board Statement: Not applicable. Institutional Review Board Statement: Not applicable. Institutional Review Board Statement: Not applicable. Informed Consent Statement: Not applicable. Informed Consent Statement: Not applicable. Data Availability Statement: Mapping results can be found at https://tinyurl.com/8hkznwxr,
accessed on 13 April 2021. Python code for results in Section 3.2 are found at https://github.com/
RJBrecha/OTEC-Caribbean, accessed on 13 April 2021. Data Availability Statement: Mapping results can be found at https://tinyurl.com/8hkznwxr,
accessed on 13 April 2021. Python code for results in Section 3.2 are found at https://github.com/
RJBrecha/OTEC-Caribbean, accessed on 13 April 2021. 5. Conclusions Conflicts of Interest: The authors declare no conflict of interest. References 1. Thomas, A.; Schleussner, C.-F.; Kumar, M. Small island developing states and 1.5 ◦C. Reg. Environ. Chang. 2018, 18, 2197–2200. [CrossRef] 2. IPCC Intergovernmental Panel on Climate Change. Global Warming of 1.5 ◦C. An IPCC Special Report on the Impacts of Global Warming
of 1.5 ◦C above Pre-Industrial Levels and Related Global Greenhouse Gas Emission Pathways; World Meteorological Organization:
Geneva, Switzerland, 2018. .F.; Huckerby, J.; Lee, K.S.; Musial, W.D.; Pontes, T.; Torres-Martinez, J.; Bharathan, D.; Hanson, H.P.; Heath 3. Lewis, A.; Estefen, S.F.; Huckerby, J.; Lee, K.S.; Musial, W.D.; Pontes, T.; Torres-Martinez, J.; Bharathan, D.; Hanson, H.P.; Heath,
G.; et al. Ocean Energy. In Renewable Energy Sources and Climate Change Mitigation; Cambridge University Press (CUP): Cambridge,
UK, 2011; pp. 497–534. G.; et al. Ocean Energy. In Renewable Energy Sources and Climate Change Mitigation; Cambridge University Press (CUP): Cambridge,
UK, 2011; pp. 497–534. pp
4. IRENA (International Renewable Energy Agency). Ocean Energy—Technology Readiness, Patent, Deployment Status and Outlook;
International Renewable Energy Agency: Abu Dhabi, United Arab Emirates, 2014. F.; Hathaway, R. Open Cycle Ocean Thermal Energy Conversion: A Preliminary Engineering Evaluation. Final
of Energy: Denver, CO, USA, 1977. 5. Watt, A.; Mathews, F.; Hathaway, R. Open Cycle Ocean Thermal Energy Conversion: A Preliminary E
Report; Department of Energy: Denver, CO, USA, 1977. 6. Vega, L.A. Economics of Ocean Thermal Energy Conversion (OTEC). In Ocean Energy Recovery: The State of the Art; American
Society of Civil Engineers: New York, NY, USA, 1992; pp. 152–181. y
g
pp
7. Lennard, D. The viability and best locations for ocean thermal energy conversion systems around the world. Renew. Energy 1995,
6, 359–365. [CrossRef] 8. Vega, L.A. Economies of ocean thermal energy conversion (OTEC): An update. In Proceedings of the Annual Offshore Technology
Conference, Houston, TX, USA, 3–6 May 2010; pp. 3239–3256. 9. Suberu, M.Y.; Mustafa, M.W.; Bashir, N. Energy storage systems for renewable energy power sector integration and mitigation of
intermittency. Renew. Sustain. Energy Rev. 2014, 35, 499–514. [CrossRef] y
gy
10. Fujita, R.; Markham, A.C.; Diaz, J.E.D.; Garcia, J.R.M.; Scarborough, C.; Greenfield, P.; Black, P.; Aguilera, S.E. Revisiting ocean
thermal energy conversion. Mar. Policy 2012, 36, 463–465. [CrossRef] gy
y
Arrow, K.J. The Economic Implications of Learning by Doing. Rev. Econ. Stud. 1962, 29, 155–173. [CrossRe 18 of 19 18 of 19 Energies 2021, 14, 2192 12. Grübler, A.; Naki´cenovi´c, N.; Victor, D.G. Dynamics of energy technologies and global change. References Notre Dame Global Adaptation Index. 2021. Available online: https://gain.nd.edu/ (accessed on 13 April 2021). 26. ND-GAIN. Notre Dame Global Adaptation Index. 2021. Available online: https://gain.nd.edu/ (a 26. ND-GAIN. Notre Dame Global Adaptation Index. 2021. Available online: https://gain.nd.edu/ (accessed on 13 April 2021). 27. Nihous, G.C. Mapping available Ocean Thermal Energy Conversion resources around the main Hawaiian Islands with state-of- 26. ND-GAIN. Notre Dame Global Adaptation Index. 2021. Available online: https://gain.nd.edu/ (accessed on 13 April 2021). 27. Nihous, G.C. Mapping available Ocean Thermal Energy Conversion resources around the main Hawaiian Islands with state-of-
the-art tools. J. Renew. Sustain. Energy 2010, 2, 43104. [CrossRef] p
p
g
27. Nihous, G.C. Mapping available Ocean Thermal Energy Conversion resources around the main Ha
the-art tools. J. Renew. Sustain. Energy 2010, 2, 43104. [CrossRef] 28. Makai Ocean Engineering. A Pre-Feasibility Study for Deep Seawater Air Conditioning Systems in the Caribbean; CAF—Latin America
Development Bank: Caracas, Venezuela, 2015. Available online: http://scioteca.caf.com/handle/123456789/806 (accessed on 13
April 2021). otti, M.; Giostri, A. Techno-economic analysis of closed OTEC cycles for power generation. Renew. Energy
3. [CrossRef] p
29. Bernardoni, C.; Binotti, M.; Giostri, A. Techno-economic analysis of closed OTEC cycles for powe
2019, 132, 1018–1033. [CrossRef] 30. Wang, M.; Jing, R.; Zhang, H.; Meng, C.; Li, N.; Zhao, Y. An innovative Organic Rankine Cycle (ORC) based Ocean Thermal
Energy Conversion (OTEC) system with performance simulation and multi-objective optimization. Appl. Therm. Eng. 2018, 145,
743–754. [CrossRef] 31. Straatman, P.J.T.; Van Sark, W.G.J.H.M. A New Hybrid Ocean Thermal Energy Conversion-Offshore
Design: A Cost Optimization Approach. Renew. Energy 2018, 82, 501–513. g
p
pp
gy
,
,
32. Park, S.; Chun, W.; Kim, N. Simulated production of electric power and desalination using Solar-OTEC hybrid system. Int. J. Energy Res. 2016, 41, 637–649. [CrossRef] 32. Park, S.; Chun, W.; Kim, N. Simulated production of electric power and desalination using Solar-OT
Energy Res. 2016, 41, 637–649. [CrossRef] gy
33. Kim, A.S.; Kim, H.-J.; Lee, H.-S.; Cha, S. Dual-use open cycle ocean thermal energy conversion (OC-OTEC) using multiple
condensers for adjustable power generation and seawater desalination. Renew. Energy 2016, 85, 344–358. [CrossRef] j
p
g
gy
34. Chen, F.; Liu, L.; Peng, J.; Ge, Y.; Wu, H.; Liu, W. Theoretical and experimental research on the thermal performance of ocean
thermal energy conversion system using the rankine cycle mode. Energy 2019, 183, 497–503. [CrossRef] 35. Ikegami, Y.; Yasunaga, T.; Morisaki, T. References Energy Policy 1999, 27, 247–280. [CrossRef] [CrossRef]
13. Nemet, G.F. Beyond the learning curve: Factors influencing cost reductions in photovoltaics. Energy Policy 2006, 34, 3218–3232. [CrossRef] 13. Nemet, G.F. Beyond the learning curve: Factors influencing cost reductions in photovoltaics. Energy Policy 2006, 34, 3218–3232. [CrossRef] [
]
14. Creutzig, F.; Agoston, P.; Goldschmidt, J.C.; Luderer, G.; Nemet, G.; Pietzcker, R.C. The underestimated potential of solar energy
to mitigate climate change. Nat. Energy 2017, 2, 17140. [CrossRef] 15. Nihous, G.C. A Preliminary Assessment of Ocean Thermal Energy Conversion Resources. J. Energy Resour. Technol. 2006, 129,
10–17. [CrossRef] 16. Lazard. Lazard’s Levelized Cost of Storage 4.0; Lazard: New York, NY, USA, 2018. 17. International Renewable Energy Agency (IRENA). Electricity Storage and Renewables: Costs and Markets to 2030; International
Renewable Energy Agency: Abu Dhabi, United Arab Emirates, 2017. Available online: https://www.irena.org/publications/20
17/Oct/Electricity-storage-and-renewables-costs-and-markets (accessed on 13 April 2021). 17/Oct/Electricity-storage-and-renewables-costs-and-markets (accessed on 13 April 2021). 18. Martin, B.; Okamura, S.; Town, K. Status of the ’Kumejima Model’ for Advanced Deep Seawater Utilization. 2016 Techno Ocean
2016, 211–216. [CrossRef] 19. Ochs, A.; Konold, M.; Auth, K.; Musolino, E.; Killeen, P. Caribbean Sustainable Energy Roadmap and Strategy; Worldwatch Institute:
Washington, DC, USA, 2015. 20. Koon Koon, R.; Marshall, S.; Morna, D.; McCallum, R.; Ashtine, M. A Review of Caribbean Geothermal Energy Resource Potential. West Indian J. Eng. 2020, 42, 37–43. 21. Chen, A.; Stephens, A.; Koon, R.K.; Ashtine, M.; Koon, K.M.-K. Pathways to climate change mitigation and stable energy by 100%
renewable for a small island: Jamaica as an example. Renew. Sustain. Energy Rev. 2020, 121, 109671. [CrossRef] 22. Bellini, E. Hydrogen Based Solar-Plus-Storage Project Launched in French Guiana. PV Magazine, 29 May 2018. Available
online: https://www.pv-magazine.com/2018/05/29/hydrogen-based-solar-plus-storage-project-launched-in-french-guiana/
(accessed on 13 April 2021). 23. National Renewable Energy Laboratory (NREL). Island Energy Snapshots; National Renewable Energy Laboratory: Denver, CO,
USA, 2021. Available online: https://www.energy.gov/eere/island-energy-snapshots (accessed on 13 April 2021). 24. Espinoza, P.; Arce, E.; Daza, D.; Faure, M.; Terraza, H. Regional Evaluation on Urban Solid Waste Management in
Latin America and the Caribbean; Inter-American Development Bank IDB-MG-115. 2010. Available online:
https:
//publications.iadb.org/publications/english/document/Regional-Evaluation-on-Urban-Solid-Waste-Management-in-
Latin-America-and-the-Caribbean-2010--Report pdf (accessed on 13 April 2021) p
g p
g
g
Latin-America-and-the-Caribbean-2010--Report.pdf (accessed on 13 April 2021). p
p
p
25. Arena, U.; Ardolino, F.; Di Gregorio, F. A life cycle assessment of environmental performances of two combustion-and gasification-
based waste-to-energy technologies. Waste Manag. 2015, 41, 60–74. [CrossRef] [PubMed] gy
g
g
26. ND-GAIN. References Ram, M.; Bogdanov, D.; Aghahosseini, A.; Gulagi, A.; Oyewo, S.A.; Child, M.; Caldera, U.; Farfan, J.; Barbosa, L.S.N.S.; Fasihi,
M.; et al. Global Energy System Based on 100% Renewable Energy—Power, Heat, Transport and Desalination Sectors Study
by Lap-peenranta University of Technology and Energy Watch Group; Lappeenranta, Berlin. March 2019. Available online:
http://energywatchgroup.org/new-study-global-energy-system-based-100-renewable-energy (accessed on 13 April 2021). 46. Löffler, K.; Hainsch, K.; Burandt, T.; Oei, P.-Y.; Kemfert, C.; von Hirschhausen, C. Designing a Model for the Global Energy
System—GENeSYS-MOD: An Application of the Open-Source Energy Modeling System (OSeMOSYS). Energies 2017, 10, 1468. by Lap-peenranta University of Technology and Energy Watch Group; Lappeenranta, Berlin. March 2019. Available online:
http://energywatchgroup.org/new-study-global-energy-system-based-100-renewable-energy (accessed on 13 April 2021). 46. Löffler, K.; Hainsch, K.; Burandt, T.; Oei, P.-Y.; Kemfert, C.; von Hirschhausen, C. Designing a Model for the Global Energy
System—GENeSYS-MOD: An Application of the Open-Source Energy Modeling System (OSeMOSYS). Energies 2017, 10, 1468. [CrossRef] 46. Löffler, K.; Hainsch, K.; Burandt, T.; Oei, P.-Y.; Kemfert, C.; von Hirschhausen, C. Designing a Model for the Global Energy
System—GENeSYS-MOD: An Application of the Open-Source Energy Modeling System (OSeMOSYS). Energies 2017, 10, 1468. [CrossRef] [
]
47. Jacobson, M.Z.; Delucchi, M.A.; Bauer, Z.A.F.; Goodman, S.C.; Chapman, W.E.; Cameron, M.A.; Bozonnat, C.; Chobadi, L.; Clonts,
H.A.; Enevoldsen, P.; et al. 100% Clean and Renewable Wind, Water, and Sunlight All-Sector Energy Roadmaps for 139 Countries
of the World. Joule 2017, 1, 108–121. [CrossRef] J
48. Jacobson, M.Z.; Delucchi, M.A.; Cameron, M.A.; Mathiesen, B.V. Matching demand with supply at low cost in 139 countries
among 20 world regions with 100% intermittent wind, water, and sunlight (WWS) for all purposes. Renew. Energy 2018, 123,
236–248. [CrossRef] 49. IRENA. Global Renewables Outlook: Energy Transformation 2050; International Renewable Energy Agency: Abu Dhabi, United Arab
Emirates, 2020. 50. IRENA. Renewable Power Generation Costs in 2018; International Renewable Energy Agency: Abu Dhabi, United Arab Emirates,
2019. 51. Lazard. Lazard’s Levelized Cost of Energy Analysis—Version 14.0; Lazard: New York, NY, USA, 2020. Available online: https:
//www.lazard.com/perspective/lcoe2020 (accessed on 13 April 2021). 52. Ueckerdt, F.; Hirth, L.; Luderer, G.; Edenhofer, O. System LCOE: What are the Costs of Variable Renewables? SSRN Electron. J. 2013, 63, 61–75. [CrossRef] 53. Yang, Y.; Bremner, S.; Menictas, C.; Kay, M. Battery energy storage system size determination in ren
A review. Renew. Sustain. Energy Rev. 2018, 91, 109–125. [CrossRef] 54. Toktarova, A.; Gruber, L.; Hlusiak, M.; Bogdanov, D.; Breyer, C. References Ocean Thermal Energy Conversion Using Double-Stage Rankine Cycle. J. Mar. Sci. Eng. 2018, 6, 21. [CrossRef] 36. Mutair, S.; Ikegami, Y. Design Optimization of Shore-Based Low Temperature Thermal Desalination System Utilizing the Ocean
Thermal Energy. J. Sol. Energy Eng. 2014, 136, 041005. [CrossRef] Yeh, R.-H.; Su, T.-Z.; Yang, M.-S. Maximum output of an OTEC power plant. Ocean Eng. 2005, 32, 685–700
Aydin, H.; Lee, H.-S.; Kim, H.-J.; Shin, S.K.; Park, K. Off-design performance analysis of a closed-cycle o
conversion system with solar thermal preheating and superheating. Renew. Energy 2014, 72, 154–163. [Cro g
p
p
p
g
38. Aydin, H.; Lee, H.-S.; Kim, H.-J.; Shin, S.K.; Park, K. Off-design performance analysis of a closed-cycle ocean thermal energy
conversion system with solar thermal preheating and superheating. Renew. Energy 2014, 72, 154–163. [CrossRef] 38. Aydin, H.; Lee, H. S.; Kim, H. J.; Shin, S.K.; Park, K. Off design performance analysis of a closed cycle ocean thermal energy
conversion system with solar thermal preheating and superheating. Renew. Energy 2014, 72, 154–163. [CrossRef] 39. Idrus, N.M.; Musa, M.; Yahya, W.; Ithnin, A. Geo-Ocean Thermal Energy Conversion (GeOTEC) power cycle/plant. Renew. Energy 2017, 111, 372–380. [CrossRef] 19 of 19 19 of 19 Energies 2021, 14, 2192 40. Hunt, J.D.; Byers, E.; Sánchez, A.S. Technical potential and cost estimates for seawater air conditioning. Energy 2019, 166, 979–988. [CrossRef] 41. Devis-Morales, A.; Montoya-Sánchez, R.A.; Osorio, A.F.; Otero-Díaz, L.J. Ocean thermal energy resources in Colombia. Renew. Energy 2014, 66, 759–769. [CrossRef] 42. Puerto Rico Department of Economic Development and Commerce (DEDC). Puerto Rico Ocean Technology Complex (PROTECH)
Proposed Roadmap for Development. 2020. Available online: https://www.ddec.pr.gov/en/protech-rfp/ (accessed on 13 April
2021). )
43. International Hydrographic Organization; UNESCO; Intergovernmental Oceanographic Commission. General Bathymetric Chart
of the Oceans. 2021. Available online: https://www.gebco.net/ (accessed on 18 February 2021). 44. Seungtaek, L.; Hosaeng, L.; Junghyun, M.; Hyeonju, K. Simulation data of regional economic analysis of OTEC for applicable
area. Processes 2020, 8, 1107. [CrossRef] 45. Ram, M.; Bogdanov, D.; Aghahosseini, A.; Gulagi, A.; Oyewo, S.A.; Child, M.; Caldera, U.; Farfan, J.; Barbosa, L.S.N.S.; Fasihi,
M.; et al. Global Energy System Based on 100% Renewable Energy—Power, Heat, Transport and Desalination Sectors Study
by Lap-peenranta University of Technology and Energy Watch Group; Lappeenranta, Berlin. March 2019. Available online:
http://energywatchgroup.org/new-study-global-energy-system-based-100-renewable-energy (accessed on 13 April 2021). 45. References Long term load projection in high resolution for all countries
globally. Int. J. Electr. Power Energy Syst. 2019, 111, 160–181. [CrossRef] g
y
J
gy
y
55. Pfenninger, S.; Staffell, I. Long-term patterns of European PV output using 30 years of validated hourly reanalysis and satellite
data. Energy 2016, 114, 1251–1265. [CrossRef] 56. Staffell, I.; Pfenninger, S. Using bias-corrected reanalysis to simulate current and future wind power output. Energy 2016, 114,
1224–1239. [CrossRef] 57. Ueckerdt, F.; Brecha, R.; Luderer, G. Analyzing major challenges of wind and solar variability in power systems. Renew. Energy
2015, 81, 1–10. [CrossRef] 58. Lazard. Lazard’s Levelized Cost of Storage—Version 6.0; Lazard: New York, NY, USA, 2020. Available onl
com/perspective/lcoe2020 (accessed on 13 April 2021). /p
p
/
(
p
)
59. IRENA. Renewable Power Generation Costs in 2019; International Renewable Energy Agency: Abu Dhabi, United Arab Emirates, 2020. p
p
p
59. IRENA. Renewable Power Generation Costs in 2019; International Renewable Energy Agency: Abu Dhab 59. IRENA. Renewable Power Generation Costs in 2019; International Renewable Energy Agency: Abu Dhabi, United Arab Emirates, 2020. 60. Hirth, L.; Ueckerdt, F.; Edenhofer, O. Integration costs revisited—An economic framework for wind and solar variability. Renew. Energy 2015, 74, 925–939. [CrossRef] 60. Hirth, L.; Ueckerdt, F.; Edenhofer, O. Integration costs revisited—An economic framework for wind and solar variability. Renew. Energy 2015, 74, 925–939. [CrossRef] 61. Bang, N.B.; Miles, L.S.; Gordon, R.D. Hurricane Occurrence and Seasonal Activity: An Analysis of the 2017 Atlantic Hurricane
Season. Am. J. Clim. Chang. 2019, 8, 454–481. [CrossRef]
|
https://openalex.org/W2996362154
|
https://www.matec-conferences.org/articles/matecconf/pdf/2019/53/matecconf_easn2019_02002.pdf
|
English
| null |
An inverse method for design and characterisation of acoustic materials
|
MATEC web of conferences
| 2,019
|
cc-by
| 2,739
|
* Corresponding author: huina@kth.se © The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons
Attribution License 4.0 (http://creativecommons.org/licenses/by/4.0/). An
inverse
method
for
design
and
characterisation of acoustic materials
Huina Mao1,*, Romain Rumpler1, and Peter Göransson1
1Department of Aeronautical and Vehicle Engineering, KTH Royal Institute of Technology,
SE-100 44 Stockholm, Sweden Huina Mao1,*, Romain Rumpler1, and Peter Göransson1 Abstract. This paper presents applications of an inverse method for the
design and characterisation of anisotropic elastic material properties of
acoustic porous materials. Full field 3D displacements under static surface
loads are used as targets in the inverse estimation to fit a material model of
an equivalent solid to the measurement data. Test cases of artificial open-
cell foams are used, and the accuracy of the results are verified. The
method is shown to be able to successfully characterise both isotropic and
anisotropic elastic material properties. The paper demonstrates a way to
reduce costs by characterising material properties based on the design
model without a need for manufacturing and additional experimental tests. MATEC Web of Conferences 304, 02002 (2019)
EASN 2019 MATEC Web of Conferences 304, 02002 (2019)
EASN 2019 https://doi.org/10.1051/matecconf/201930402002 1 Introduction Acoustic materials are popular in the industry for sound absorption, soundproof, sound
wave manipulation, etc. Among those, porous materials are one of the most used for sound
absorption [1]. The majority of the studies to date have concentrated on conventional
porous materials of equivalent isotropic or transverse isotropic [2-4]. However, the
properties of lightweight porous materials are highly dependent on the microstructure and
geometry, possibly holding anisotropy in the macroscopic properties of the material in
production process or design, as the melamine foam with non-zero shear-compression
coupling moduli and negative Poisson's ratio [5]. In addition, some applications require
porous acoustic materials exhibiting anisotropic behaviour in certain direction. e.g.,
anisotropic acoustic metamaterials designed to manipulate sound waves [6]. The progress
observed in manufacturing technologies, such as 3-D Printer, micro- and nano-
manufacturing techniques, open a door to design artificial materials for specific mechanical
applications, and motivate the characterisation of anisotropic materials by giving designed
model. However, the few studies of artificial porous materials have not provided a way to
guide the design of acoustic foams based on the application functions. Thus, developing or
applying a method that can characterise the material properties during early design phases
becomes critical. Several contributions have attempted to characterise acoustical porous material
properties over the last decades from experimental, analytical and numerical methods, see
e.g. [4, 5, 7-13], but limited to isotropic or transversely isotropic materials and omitting the MATEC Web of Conferences 304, 02002 (2019)
EASN 2019 https://doi.org/10.1051/matecconf/201930402002 three-dimensional local effects. Inverse estimation is a widely used method for the
characterisation of elastic material properties of porous materials [7, 9, 11-13]. In recent
works by the authors in [14], related to the characterisation of porous elastic foams, an
inverse method was proposed, and the accuracy was numerically verified. three-dimensional local effects. Inverse estimation is a widely used method for the
characterisation of elastic material properties of porous materials [7, 9, 11-13]. In recent
works by the authors in [14], related to the characterisation of porous elastic foams, an
inverse method was proposed, and the accuracy was numerically verified. The aim of the present paper is to address the inverse method in context of design and
characterisation of anisotropic porous foams. The paper is organised as follows. First, the
method in paper [14] is adapted for its application to acoustic porous materials and the
microstructures are simplified by open-cell Kelvin cells. 2 Method and structure introduction An inverse estimation methodology for the different moduli in the static Hooke's matrix
H of open-cell materials was developed by the authors in [14]. The data used for the
approach consists of displacements of target Kelvin model and displacements of predicted
solid homogeneous model, see Fig. 1. The Hooke's matrix of the predicted model is varied
within an optimisation routine until the difference between target and predicted
displacements is minimised. The displacements are obtained as the result of a static
compression and a shear load by a displacement of 0.01 mm between two flat plates of a
cubic sample of material in each orthogonal direction, x, y and z. A schematic
representation of the measurement setup is given in Fig. 2 for a compression of the material
in the y-direction. In addition to the measurement of the displacements, the static force
needed to compress the material sample must be measured for a complete characterisation
of the Hooke's matrix. More details about the method and modelling set-up may be find in
[11]. The frame of the porous material is assumed to have anisotropic material properties and
the influence of pressure variations in the air are neglected under a quasi-static loading [15]. The frame behaves as an equivalent homogeneous solid yielding the constitutive equation
for the frame in the form of a Hooke's law such that σ = Hε
(1)
σ ={ σ11, σ22, σ33, σ12, σ13, σ23 }
(2)
ε ={ ε11, ε 22, ε 33, ε 12, ε 13, ε 23 }
(3) (1) (2) (3) ε ={ ε11, ε 22, ε 33, ε 12, ε 13, ε 23 } where H is the static, elastic Hooke's matrix in stiffness form, σ is the stress, and ε is the
strain vector. The fully aniostropic elasticity requires 21 independent parameters in the
elastic Hooke's tensor. where H is the static, elastic Hooke's matrix in stiffness form, σ is the stress, and ε is the
strain vector. The fully aniostropic elasticity requires 21 independent parameters in the
elastic Hooke's tensor. The anisotropic elastic properties of porous materials may arise from diverse
reasons, e.g. manufacturing, pre-strain, distributions, geometry shape, etc. Since the
purpose of the paper is to demonstrate the method in design applications, a straightforward
approach by modification of Kelvin cell microstructures is used to generate anisotropic
foam materials. 1 Introduction The method is then applied to the
characterisation of isotropic and anisotropic artificial porous foams and the results are
presented and discussed with respect to previous works. The paper is ends with conclusions
and perspectives. 2 Method and structure introduction The Kelvin cell has a relatively simple geometry but can generate complex
enough anisotropic material properties [2–4, 8, 13, 16–18]. The general Kelvin unit cell has 14 polyhedron sides including eight hexagonal faces
and six square faces. Its cell size is denoted as Sx, Sy and Sz in the x, y and z-direction
respectively, see Fig. 3. Isotropic Kelvin cells and anisotropic Kelvin cells of mixed struts
are given as examples in Fig. 3. Geometric and material properties of the Kelvin cells are 2 MATEC Web of Conferences 304, 02002 (2019)
EASN 2019 https://doi.org/10.1051/matecconf/201930402002 shown in Table 1, where the circular strut shape was used for the sake of simplicity. The
Young's modulus of the matrix material is E and the Poisson's modulus is ν. Fig. 1. Inverse method flowchart: minimisation of the displacement difference on free faces (colour
contour plot) between the target and predicted models. shown in Table 1, where the circular strut shape was used for the sake of simplicity. The
Young's modulus of the matrix material is E and the Poisson's modulus is ν. shown in Table 1, where the circular strut shape was used for the sake of simplicity. The
Young's modulus of the matrix material is E and the Poisson's modulus is ν. Fig. 1. Inverse method flowchart: minimisation of the displacement difference on free faces (colour
contour plot) between the target and predicted models. Fig. 2. Representation of the Kelvin cell and solid model in the case of a compression along y-axis. Fig. 2. Representation of the Kelvin cell and solid model in the case of a compression along Fig. 3. Sketch of a unit Kelvin cell: a) isotropic cell, c) anisotropic cell with mixed struts of weak (red
lines) and normal struts. Fig. 3. Sketch of a unit Kelvin cell: a) isotropic cell, c) anisotropic cell with mixed struts of weak (red
lines) and normal struts. Fig. 3. Sketch of a unit Kelvin cell: a) isotropic cell, c) anisotropic cell with mixed struts of weak (
lines) and normal struts. Table 1. Geometric and material properties of the Kelvin cells. Table 1. Geometric and material properties of the Kelvin cells. 2 Method and structure introduction Quantity
Symbol
Isotropic
Anisotropic
Unit
Cell width in x, y, z-direction
D
3
3
mm
Cross section radius of normal struts
rn
0.25
0.25
mm
Cross section radius of weak struts
rw
-
0.13
mm
Solid density of strut material
ρ
1600
1600
kg/m3
Young's modulus of strut material
E
563
563
MPa
Poisson's ratio of strut material
ν
0.3
0.3
- 3 https://doi.org/10.1051/matecconf/201930402002 MATEC Web of Conferences 304, 02002 (2019)
EASN 2019 3 Result and discussion Figs. 4 and 5 show that the deformation components of the equivalent model are nearly
the same as the target model loads with a very small deviation. All deformation under
compression and shearing are recovered in the equivalent model. The displacement
differences between the predicted and the target displacements for each applied load are
less than 0.07%. The negligible difference may be due to various reasons, e.g., boundary
condition, different element type between the target and predicted model, etc. Table 1 shows the predicted Hooke's tensors of the isotropic and anisotropic cases, and
the difference between them. The results show that the mixed cross-section struts
introduced anisotropic properties to the KC model, i.e., all Hooke's tensor components Hij <
0 for the mixed struts case. The location of reduced cross-sections struts dominates the
shear-compression coupling effects. The terms of compression and shearing moduli, Hii,
decreased by around 30% due to the weak struts. The results also indicate that the
modification of specific struts in the open-cell geometry, e.g., changing cross-section areas,
could provide a way to tune the moduli of the anisotropic Hooke's matrix. Fig. 4. Compression load case of the anisotropic design with zero displacements at the y=ymin face,
imposed displacement of 0.01mm in the y-direction at the y=ymax face, results shown are the
displacement component in the x-direction for the a) anisotropic Kelvin model and b) the predicted
equivalent solid model. Fig. 4. Compression load case of the anisotropic design with zero displacements at the y=ymin face,
imposed displacement of 0.01mm in the y-direction at the y=ymax face, results shown are the
displacement component in the x-direction for the a) anisotropic Kelvin model and b) the predicted
equivalent solid model. Fig. 5. Shear load case of the anisotropic design with zero displacements at the x=xmax face, shear
displacement 0.01 mm in the y-direction at the x=xmin face, results shown are the displacement
component in the z-direction for the a) anisotropic Kelvin model and b) the predicted equivalent solid
models. Fig. 5. Shear load case of the anisotropic design with zero displacements at the x=xmax face, shear
displacement 0.01 mm in the y-direction at the x=xmin face, results shown are the displacement
component in the z-direction for the a) anisotropic Kelvin model and b) the predicted equivalent solid
models. 4 4 https://doi.org/10.1051/matecconf/201930402002 MATEC Web of Conferences 304, 02002 (2019)
EASN 2019 Table 2. 3 Result and discussion Predicted Hooke’s tensor components: isotropic and mixed struts anisotropic Kelvin cells. Hij
Isotropic
Anisotropic
(Haniso-Hiso)/Hiso (%)
H11
14.626
10.2648
-29.8189
H12
9.6332
7.1356
-25.9269
H22
14.699
10.3190
-29.7972
H13
9.576
7.0583
-26.2919
H23
9.6108
7.1030
-26.0938
H33
14.610
10.1921
-30.2367
H14
0
0.2952
--
H24
0
0.2922
--
H34
0
0.2196
--
H44
2.5993
1.7084
-34.2748
H15
0
0.2847
--
H25
0
0.2140
--
H35
0
0.2844
--
H45
0
0.3010
--
H55
2.6141
1.6983
-35.0318
H16
0
0.2187
--
H26
0
0.2926
--
H36
0
0.2963
--
H46
0
0.2921
--
H56
0
0.3043
--
H66
2.6167
1.7151
-34.4539 4 Conclusion The paper shows that the elastic Hooke's tensor including 21 parameters is successfully
characterised for anisotropic porous foams using an proposed inverse estimation
methodology by the authors. Deformations of the target foam under compression and shear
loads are recovered in the equivalent model. Both the Young's modulus and the shear
modulus are identified in the isotropic model, and the full Hooke’s tensor is properly
characterised in the anisotropic model. This highlights, therefore, that the inverse method
could apply both to isotropic and anisotropic foams. Additionally, it is shown that changing 5 5 MATEC Web of Conferences 304, 02002 (2019)
EASN 2019 https://doi.org/10.1051/matecconf/201930402002 cross-section areas of struts provides a possible way to tune the moduli in the Hooke's
tensor. Extending this preliminary study to several modification including the analysis of
several forms of the influence of geometry, or the influence of solid matrix parameters, are
required in order to further apply the inverse method to acoustic material design. cross-section areas of struts provides a possible way to tune the moduli in the Hooke's
tensor. Extending this preliminary study to several modification including the analysis of
several forms of the influence of geometry, or the influence of solid matrix parameters, are
required in order to further apply the inverse method to acoustic material design. 5 Acknowledgments This work is being partially supported by H2020-EU.3.4. – societal challenges – smart,
green and integrated transport, project grant 723367, Advanced aircraft-noise-alleviation
devices using metamaterials. References 1. X. Tang, X. Yan, Acoustic energy absorption properties of fibrous materials: A review,
Composites Part A: Applied Science and Manufacturing 101 (2017) 360–380 2. W. Warren, A. Kraynik, Linear elastic behavior of a low-density Kelvin foam with
open cells, Journal of Applied Mechanics 64 (4) (1997) 787–794 3. H. Zhu, J. Knott, N. Mills, Analysis of the elastic properties of open-cell foams with
tetrakaidecahedral cells, Journal of the Mechanics and Physics of Solids 45 (3) (1997)
319–343 4. R. M. Sullivan, L. J. Ghosn, Shear moduli for non-isotropic, open cell foams using a
general elongated Kelvin foam model, International Journal of Engineering Science 47
(10) (2009) 990–1001 5. J. Cuenca, C. Van der Kelen, P. Göransson, A general methodology for inverse
estimation of the elastic and anelastic properties of anisotropic open-cell porous
materials—with application to a melamine foam, Journal of Applied Physics 115 (8)
(2014) 084904 6. G. Palma, H. Mao, L. Burghignoli, P. Göransson, U. Iemma, Acoustic Metamaterials
in Aeronautics, Applied Sciences 8 (6) (2018) 971 7. M. Melon, E. Mariez, C. Ayrault, S. Sahraoui, Acoustical and mechanical
characterization of anisotropic open-cell foams, The Journal of the Acoustical Society
of America 104 (5) (1998) 2622–902627 8. L. Gong, S. Kyriakides, W.-Y. Jang, Compressive response of open-cell foams. Part I:
Morphology and elastic properties, International Journal of Solids and Structures 42 (5-
6) (2005) 1355–1379 9. R. Guastavino, P. Göransson, A 3D displacement measurement methodology for
anisotropic porouscellular foam materials, Polymer Testing 26 (6) (2007) 711–719 10. L. Jaouen, A. Renault, M. Deverge, Elastic and damping characterizations of acoustical
porous materials: Available experimental methods and applications to a melamine
foam, Applied acoustics 69 (12) (2008) 1129–1140 11. A. Geslain, O. Dazel, J.-P. Groby, S. Sahraoui, W. Lauriks, Influence of static
compression on mechanical parameters of acoustic foams, The Journal of the
Acoustical Society of America 130 (2) (2011) 818–825 12. C. Van der Kelen, J. Cuenca, P. Göransson, A method for the inverse estimation of
the static elastic compressional moduli of anisotropic poroelastic foams–With
application to a melamine foam, Polymer Testing 43 (2015) 123–130 6 6 MATEC Web of Conferences 304, 02002 (2019)
EASN 2019 https://doi.org/10.1051/matecconf/201930402002 13. G. Yan, X. Guo, B. Brouard, S. Sahraoui, Static Stiffness Method for Elastic Constants
Determination of Anisotropic Acoustic Foams, Acta Acustica united with Acustica 103
(4) (2017) 650–656 14. H. Mao, R. Rumpler, P. References Göransson, An inverse method for characterisation of the
static elastic Hooke’s tensors of solid frame of anisotropic open-cell materials,
International Journal of Engineering Science (submitted) 15. N.-E. Hörlin, P. Göransson, Weak, anisotropic symmetric formulations of Biot’s
equations for vibro-acoustic modelling of porous elastic materials, International
Journal for Numerical Methods in Engineering 84 (12) (2010) 1519–1540 16. W. Warren, A. Kraynik, The linear elastic properties of open-cell foams, Journal of
Applied Mechanics 55 (2) (1988) 341–346 17. S. Sahraoui, E. Mariez, M. Etchessahar, Linear elastic properties of anisotropic open-
cell foams, The Journal of the Acoustical Society of America 110 (1) (2001) 635–637 18. W.-Y. Jang, S. Kyriakides, A. M. Kraynik, On the compressive strength of open-cell
metal foams with Kelvin and random cell structures, International Journal of Solids
and Structures 47 (21) (2010)2872 – 2883 7
|
https://openalex.org/W2257436858
|
https://stemcellres.biomedcentral.com/track/pdf/10.1186/s13287-016-0281-8
|
English
| null |
Tracking of autologous adipose tissue-derived mesenchymal stromal cells with in vivo magnetic resonance imaging and histology after intralesional treatment of artificial equine tendon lesions - a pilot study
|
Stem cell research & therapy
| 2,016
|
cc-by
| 8,988
|
Tracking of autologous adipose tissue-
derived mesenchymal stromal cells with
in vivo magnetic resonance imaging and
histology after intralesional treatment of
artificial equine tendon lesions - a pilot
study Florian Geburek1*, Kathrin Mundle2, Sabine Conrad3, Maren Hellige1, Ulrich Walliser2, Hans T. M. van Schie4,
René van Weeren4, Thomas Skutella5 and Peter M. Stadler1 * Correspondence: Florian.Geburek@tiho-hannover.de
1Clinic for Horses, University of Veterinary Medicine Hannover, Foundation,
Bünteweg 9, 30559 Hannover, Germany
Full list of author information is available at the end of the article © 2016 Geburek et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Geburek et al. Stem Cell Research & Therapy (2016) 7:21
DOI 10.1186/s13287-016-0281-8 Geburek et al. Stem Cell Research & Therapy (2016) 7:21
DOI 10.1186/s13287-016-0281-8 * Correspondence: Florian.Geburek@tiho-hannover.de
1Clinic for Horses, University of Veterinary Medicine Hannover, Foundation,
Bünteweg 9, 30559 Hannover, Germany
Full list of author information is available at the end of the article
© 2016 Geburek et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Background necessary [10]. In vitro studies have shown that con-
trolled
labelling
of MSCs with SPIO nanoparticles
neither caused death of rabbit BM-MSCs nor inhibited
their proliferation [15]. A recent equine study has pro-
vided evidence that viability did not differ between
SPIO-labelled and unlabelled BM-MSCs and umbilical
cord blood MSCs. However, doubling time increased in
SPIO-labelled MSCs compared with unlabelled cells
[16]. In a rodent study, SPIO nanoparticles could be
tracked in vivo for up to 4 weeks after subcutaneous im-
plantation [17]. At the same time, in a different rodent
study investigating the presence of SPIO-labelled BM-
MSCs at a tendon-to-bone interface for up to 7 days, a
reliable tracing of labelled cells was impossible and this
was due to the similar signal intensity of cells and ten-
don tissue on T2-weighted MRI images [18]. As recently
pointed out in an equine cadaver study, SPIO-labelled
BM-MSCs are detectable immediately after intralesional
SDFT injection by using 1.5-Tesla MRI [16]. g
Injury of the superficial digital flexor tendon (SDFT) is
common, especially in thoroughbred racehorses [1]. Therapy with adipose-derived nucleated cells and adipose
tissue-derived mesenchymal stromal cells (AT-MSCs) has
shown promising results when treating both experimental
tendonitis [2–5] and naturally occurring tendon and liga-
ment injuries in horses [6, 7]. To further investigate the
potential regenerative, immunomodulatory and inflamma-
tory modulating effect of MSC therapy, knowledge of the
distribution, kinetics and engraftment of the injected cells
in the target tissue is of utmost interest [8]. Bone marrow-
derived MSCs (BM-MSCs) and embryonic-like stem cells
(ESCs) have been traced after labelling with green fluores-
cent protein (GFP) and were detectable in the treated
tendon for up to 90 days [9, 10]. Whereas estimated BM-
MSC survival was less than 5 % after 10 days, ESC num-
bers were at a constant level for 90 days [10]. Compared
with MSCs from other sources, AT-MSCs show expres-
sion of extracellular matrix proteins with the highest colla-
gen 1A2-to-collagen 3A1 ratios. Moreover, AT-MSCs
display the second highest expression of the tendon
markers tenascin-C and scleraxis [11], suggesting that AT-
MSCs may be of special benefit in the treatment of equine
tendinopathy. However, knowledge about the fate of au-
tologous AT-MSCs after intralesional injection into equine
SDFTs is marginal. Abstract Background: Adipose tissue-derived mesenchymal stromal cells (AT-MSCs) are frequently used to treat equine
tendinopathies. Up to now, knowledge about the fate of autologous AT-MSCs after intralesional injection into
equine superficial digital flexor tendons (SDFTs) is very limited. The purpose of this study was to monitor the
presence of intralesionally injected autologous AT-MSCs labelled with superparamagnetic iron oxide (SPIO)
nanoparticles and green fluorescent protein (GFP) over a staggered period of 3 to 9 weeks with standing
magnetic resonance imaging (MRI) and histology. Methods: Four adult warmblood horses received a unilateral injection of 10 × 106 autologous AT-MSCs into surgically
created front-limb SDFT lesions. Administered AT-MSCs expressed lentivirally transduced reporter genes for GFP and
were co-labelled with SPIO particles in three horses. The presence of AT-MSCs in SDFTs was evaluated by
repeated examinations with standing low-field MRI in two horses and post-mortem in all horses with Prussian
blue staining, fluorescence microscopy and with immunofluorescence and immunohistochemistry using anti-GFP
antibodies at 3, 5, 7 and 9 weeks after treatment. Results: AT-MSCs labelled with SPIO particles were detectable in treated SDFTs during each MRI in T2*- and
T1-weighted sequences until the end of the observation period. Post-mortem examinations revealed that all
treated tendons contained high numbers of SPIO- and GFP-labelled cells. (Continued on next page) © 2016 Geburek et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Page 2 of 12 Geburek et al. Stem Cell Research & Therapy (2016) 7:21 (Continued from previous page) Conclusions: Standing low-field MRI has the potential to track SPIO-labelled AT-MSCs successfully. Histology,
fluorescence microscopy, immunofluorescence and immunohistochemistry are efficient tools to detect labelled AT-
MSCs after intralesional injection into surgically created equine SDFT lesions. Intralesional injection of 10 × 106 AT-MSCs
leads to the presence of high numbers of AT-MSCs in and around surgically created tendon lesions for up to 9 weeks. Integration of injected AT-MSCs into healing tendon tissue is an essential pathway after intralesional administration. Background As recently revealed, AT-MSCs
labelled with nanocrystals were detectable in peripheral
blood for 72 h and 7 days after implantation as well as in
SDFT tissue 7 days after intralesional injection in an
equine collagenase tendonitis model [12]. The present pilot study aimed at testing whether
standing low-field MRI has the potential to monitor
the fate of intralesionally injected AT-MSCs labelled
with SPIO particles in vivo and at monitoring the
presence of AT-MSCs that were co-labelled with GFP
histologically for up to 9 weeks in a surgical model of
equine tendinopathy. Abstract Injection techniques have to be chosen deliberately to avoid reflux of the cell substrate injected. In vivo low-field MRI may
be used as a non-invasive tool to monitor homing and engraftment of AT-MSCs in horses with tendinopathy of the SDFT. Keywords: Horse, Superficial digital flexor tendon, Superparamagnetic iron oxide particles, SPIO, Prussian blue staining,
Green fluorescent protein Methods Four warmblood horses (two stallions, one mare and
one gelding) between 1 and 4 years old were objects
of this study. Pre-existing tendon injury was excluded
by clinical examination, B-mode ultrasonography and
ultrasonographic tissue characterization (UTC) (UTC
2009; UTC Imaging, Stein, The Netherlands). The
study was approved by the animal welfare officer of the
University of Veterinary Medicine Hannover, Foundation,
Germany, and the ethics committee of the responsible
German federal state authority in accordance with the
German Animal Welfare Law (Lower Saxony State
Office for Consumer Protection and Food Safety, Az. 33.9-42502-04-08/1622). Labelling with superparamagnetic iron oxide (SPIO)
nanoparticles is a technique to track MSCs assisted by
magnetic resonance imaging (MRI) because of the
strength of the signal change per unit of metal provided,
particularly in T2*-weighted images [13]. By means of
this technique, cells can be monitored non-invasively
in vivo and at post-mortem histology by Prussian blue
staining [14]. In contrast, GFP-based labelling tech-
niques are dependent on tissue biopsies or even larger
specimen, thus making euthanasia of the treated animal Page 3 of 12 Page 3 of 12 Geburek et al. Stem Cell Research & Therapy (2016) 7:21 cells as well as cell aggregates were excluded from fur-
ther analysis according to forward scatter (FSC) and side
scatter (SSC) properties (gate P1 and P2). For the detection
of GFP fluorescence intensity, a combination of a 502
low-pass (LP) and 530/30 band-pass (BP) filter in
front of the photomultiplier tube (PMT) detector
(488-E) was employed. Detection sensitivity was set with a
non-expressing control sample. The GFP-positive gate
(P3) was set on the basis of the negative control popula-
tion to include 0.0 % positive events. The mean efficacy of
transfection was estimated to be 99 % after passage 0
(horse 2) and 63 %, 62 %, and 64 % after passage 2 (horses
1, 3 and 4) as determined by three analyses, respectively. Collection of subcutaneous fat, AT-MSC isolation, and culture
After sedation of the horses, approximately 1–2 g of
subcutaneous fat was harvested from the left coccygeal
region at the base of the tail 8 or 9 days prior to surgical
creation of standardized SDFT lesions. AT-MSCs were
isolated and cultured as described elsewhere [4]. They
were defined by the presence of markers CD44, CD90,
CD105 and CD117 and the absence of CD34 and CD45. Labelling with lentiviral plasmid and superparamagnetic
iron oxide particles After the addition of 10 μg/ml polybrene, the cultured
AT-MSCs of all horses were incubated with lentivirus
particles with a copGFP (hUbiC Promoter) for 48 h. The
efficacy of transfection was controlled by fluorescence
microscopy during passage 1 (Fig. 1) and by flow cyto-
metric analysis (Fig. 2) which was performed on a BD
FACSCanto™II with BD FACSDiva™8.0.1 software (BD
Biosciences, Franklin Lakes, NJ, USA). For excitation,
the 488-nm laser line was used. Debris, dead or damaged Additionally, AT-MSCs from horses 1, 2 and 4 were
labelled by incubation with 45- to 60-nm SPIO particles
coated
with
carboxydextran
(Resovist™,
SHU
555A;
Schering AG, Berlin, Germany) in culture medium for
48 h at an SPIO concentration of 60 μg/ml Fe. Following
the
incubation,
AT-MSCs
were
rinsed
thrice
with
phosphate-buffered saline (PBS) solution. After harvest # 2
GFP cells
Merge
Brightfield
100µm
# 4
# 1
# 3
Fig. 1 Photomicrographs of cultured adipose-derived mesenchymal stromal cells from horses 1 to 4 after transfection with lentiviral green fluorescent
protein (GFP) construct. Bright field (left), fluorescence (middle) and merged (right) images are shown. Approximately 70–90 % of the cells were positive
for GFP in their cytoplasm during passage 1. Magnification: 10×. Scale bar: 100 μm Fig. 1 Photomicrographs of cultured adipose-derived mesenchymal stromal cells from horses 1 to 4 after transfection with lentiviral green fluorescent
protein (GFP) construct. Bright field (left), fluorescence (middle) and merged (right) images are shown. Approximately 70–90 % of the cells were positive
for GFP in their cytoplasm during passage 1. Magnification: 10×. Scale bar: 100 μm Geburek et al. Stem Cell Research & Therapy (2016) 7:21 Page 4 of 12 a
b
0%
98,9%
64,0%
63,6%
62,2%
Fig. 2 Flow cytometric analysis of cultured AT-MSCs from horses 1 to 4 after transfection with lentiviral green fluorescent protein (GFP) construct. From left to right are (a) scatter plots and (b) histograms, including percentages showing the distribution of GFP-expressing cells in a
non-expressing control sample (ctrl-no GFP) and in samples from horse 2 (I-VP1; passage 0) and horses 1, 3 and 4 (I-VP3, I-VP4 and I-VP2; passage
2) after a single analysis. Green indicates GFP-labelled AT-MSCs, and blue indicates non-labelled AT-MSCs. AT-MSC adipose tissue-derived
mesenchymal stromal cell, FSC-A forward scatter A, GFP green fluorescent protein, SSC-A side scatter A a a b
0%
98,9%
64,0%
63,6%
62,2%
Fig. Labelling with lentiviral plasmid and superparamagnetic
iron oxide particles 2 Flow cytometric analysis of cultured AT-MSCs from horses 1 to 4 after transfection with lentiviral green fluorescent protein (GFP) construct. From left to right are (a) scatter plots and (b) histograms, including percentages showing the distribution of GFP-expressing cells in a
non-expressing control sample (ctrl-no GFP) and in samples from horse 2 (I-VP1; passage 0) and horses 1, 3 and 4 (I-VP3, I-VP4 and I-VP2; passage
2) after a single analysis. Green indicates GFP-labelled AT-MSCs, and blue indicates non-labelled AT-MSCs. AT-MSC adipose tissue-derived
mesenchymal stromal cell, FSC-A forward scatter A, GFP green fluorescent protein, SSC-A side scatter A b
0%
98,9%
64,0%
63,6%
62,2%
Fig. 2 Flow cytometric analysis of cultured AT-MSCs from horses 1 to 4 after transfection with lentiviral green fluorescent protein (GFP) construct. From left to right are (a) scatter plots and (b) histograms, including percentages showing the distribution of GFP-expressing cells in a
non-expressing control sample (ctrl-no GFP) and in samples from horse 2 (I-VP1; passage 0) and horses 1, 3 and 4 (I-VP3, I-VP4 and I-VP2; passage
2) after a single analysis. Green indicates GFP-labelled AT-MSCs, and blue indicates non-labelled AT-MSCs. AT-MSC adipose tissue-derived
mesenchymal stromal cell, FSC-A forward scatter A, GFP green fluorescent protein, SSC-A side scatter A b
0%
98,9%
63,6%
62,2% b Fig. 2 Flow cytometric analysis of cultured AT-MSCs from horses 1 to 4 after transfection with lentiviral green fluorescent protein (GFP) construct. From left to right are (a) scatter plots and (b) histograms, including percentages showing the distribution of GFP-expressing cells in a
non-expressing control sample (ctrl-no GFP) and in samples from horse 2 (I-VP1; passage 0) and horses 1, 3 and 4 (I-VP3, I-VP4 and I-VP2; passage
2) after a single analysis. Green indicates GFP-labelled AT-MSCs, and blue indicates non-labelled AT-MSCs. AT-MSC adipose tissue-derived
mesenchymal stromal cell, FSC-A forward scatter A, GFP green fluorescent protein, SSC-A side scatter A Geburek et al. Stem Cell Research & Therapy (2016) 7:21 Page 5 of 12 Page 5 of 12 Geburek et al. Stem Cell Research & Therapy (2016) 7:21 Initially the horses were sedated with romifidine
(0.06 mg/kg bwt [IV] and butorphanol (0.01 mg/kg bwt
[IV]). The sedation was prolonged to effect with detomi-
dine (0.01 mg/kg bwt [IV]). Follow-up Following the creation of the lesions, the horses received
box rest for 3 weeks. Thereafter they were exercised in
accordance with a protocol adapted from Bosch et al. (2010) [21] until euthanasia: From week 4 to 6, they
were walked for 10 min once a day on a treadmill. During week 7 to 9, walking was extended to 20 min
once daily. After sedation with xylazine (0.4 mg/kg bwt
[IV]) and levomethadone (0.05 mg/kg bwt [IV]) and in-
duction of general anaesthesia with ketamine (3 mg/kg
bwt [IV]) and midazolam (0.02 mg/kg bwt [IV]), horses
were euthanized by using an overdose of pentobarbital
(80 mg/kg bwt [IV]) at 3, 5, 7 and 9 weeks after injection
of the cells, respectively. Creation of superficial digital flexor tendon lesions Creation of superficial digital flexor tendon lesions
Lesions were created in the SDFTs of both front
limbs under general anaesthesia by using a technique
previously described [19–21]. A short longitudinal in-
cision was made axially at the palmar aspect of the
metacarpus just proximal to the digital sheath. A con-
ical obturator (Ø 3.5 mm) from an arthroscope was
introduced through a stab incision into the center of
the SDFT and advanced proximally for 7–8 cm while
carefully avoiding penetration of the epitenon. The
obturator was replaced by an arthroscopic burr (Small
Joint Round Burr ø 3.5 mm, 28204 FB; Karl Storz
GmbH & Co. KG, Tuttlingen, Germany), which was
activated and slowly withdrawn within approximately
20 s. The incisions were closed in a simple interrupted
pattern. The horses received meloxicam (0.6 mg/kg body
weight (bwt) [orally]) the day of surgery and for two con-
secutive days. Labelling with lentiviral plasmid and superparamagnetic
iron oxide particles After positioning of the
metacarpal regions in the isocenter of the magnet, the
following MRI sequences and variables were applied:
transverse gradient-echo T1-weighted, TR (relaxation
time): 50 ms, TE (echo time): 8.0 ms, FA (flip angle): 50°,
matrix size: 170 × 130, number of excitations: 1; trans-
verse gradient-echo T2*-weighted, FA: 25°, matrix size:
170 × 126; number of excitations: 1; transverse STIR, TR:
2260 ms, TE: 22.0 ms, FA: 90°, matrix size: 168 × 168,
number of excitations: 8. The field-of-view angle was
170 × 170 mm, the slide width was 5.0 mm and the gap
width was 6.0 mm. of AT-MSCs from passage 0, the total number of cells
was counted and the cell viability evaluated, followed by
sample preparation of 10 × 106 AT-MSCs on ice for
transplantation. Cells not needed for transplantation
were cryopreserved for further experiments. of AT-MSCs from passage 0, the total number of cells
was counted and the cell viability evaluated, followed by
sample preparation of 10 × 106 AT-MSCs on ice for
transplantation. Cells not needed for transplantation
were cryopreserved for further experiments. Injection of labelled AT-MSCs The tendon lesions were treated unilaterally with
AT-MSCs at 1 week (horses 2 and 3) and at 3 weeks
(horses 1 and 4) after surgery. Three horses (1, 2
and 4) received AT-MSCs labelled with SPIO parti-
cles. The horses were sedated by using detomidine
hydrochlorid (0.02 mg/kg bwt [IV]) and butorphanol
(0.04 mg/kg bwt [IV]). Additionally the medial and lateral
palmar nerves were anaesthetized with 2 ml of 2 % mepi-
vacaine hydrochlorid 2 cm distal to the carpometacarpal
joint. Approximately 10 × 106 AT-MSCs suspended in
2 ml 0.9 % saline (total volume 3 ml) and divided into ali-
quots of 1.5 ml were injected into the SDFT lesions from
lateral under ultrasonographic guidance by using a 23-G,
1-inch needle. Entrance of the needle was 3 and 5 cm
proximal to the surgical scar. Following the implantation
of the cells, the limbs were dressed with half-limb ban-
dages for 16 days. The contralateral SDFT was treated
with 3 ml of saline in the same manner. Fluorescence microscopy and Prussian blue staining
The SDFTs were dissected immediately after death, and
a tendon segment including the lesion was harvested
from between 4 and 5 cm proximal to the surgical scar. These specimens were stored for 96 h in 4 % parafor-
maldehyde followed by 96 h in PBS. Thereafter they
were snap-frozen in Tissue-Tek (Sakura, Alphen aan den
Rijn, The Netherlands) at −180 °C. Transverse sections
with a thickness of 10 μm were cut with a cryostat and
distended on histology slides. Sections were fixed with
4 % paraformaldehyde for 10 min, washed with PBS and
stored at −80 °C after drying until required. Slices
were examined under a fluorescence microscope (20×
magnification). A set of frozen sections was stained
with Prussian blue as described elsewhere (immuno-
histochemistry
world)
and
examined
with
a
light
microscope (20× magnification). Standing low-field magnetic resonance imaging g
g
g
g
In two of the horses treated with SPIO-labelled AT-
MSCs (2 and 4), sequential standing low-field MRI of
the metacarpal regions was performed by using a clinical
0.27-Tesla open magnet (Hallmarq Veterinary Imaging,
Guildford, Surrey, UK) and a fetlock radiofrequency coil. Front-limb SDFTs were scanned 6 and 33 days after the
intralesional treatment in horse 2 and after 2, 18, 47 and
62 days in horse 4. MRI tracking of SPIO-labelled AT-MSCs MRI tracking of SPIO labelled AT MSCs
In horse 4, areas with hypointense signal, representing a
magnetic susceptibility artefact resulting from SPIO par-
ticles, surrounded by regions of increased signal inten-
sity, were detectable on transverse T2*-weighted MRI
images in and around the SDFT at days 2, 18, 47 and 62
after
treatment
(Fig. 7a). T1-weighted
images
also
showed a negative contrast in the lesions and in their
lateral periphery (Fig. 7c). Areas of signal void corre-
sponded to the two sites of injection in both sequences. In horse 2, a corresponding finding was present at 6 and
33 days after treatment. As compared with the contralat-
eral SDFT, areas of decreased signal intensity were Immunohistochemistry and immunofluorescence The cell culture and frozen tissue sections were analysed
immunohistochemically and with immunofluorescence
to detect the GFP antigen. Incubations with the primary
polyclonal antibody rabbit-Anti-CopGFP (Evrogen AB Geburek et al. Stem Cell Research & Therapy (2016) 7:21 Page 6 of 12 513; Evrogen, Moscow, Russia) diluted at 1:1000 were
carried out overnight at 4 °C. After incubation with the
primary antibody, one set of sections was incubated with
a
biotylinated
swine-anti-rabbit
secondary
antibody
(E0431; Dako, Hamburg, Germany) at a dilution of 1:400
for 60 min at room temperature. Thereafter, the peroxid-
ase streptavidin-biotin-complex (ABC) detection system
(Vectastain Elite ABC Kit; Vector Laboratories Inc.,
Burlingame, CA, USA) was applied and slices were
exposed to diaminobenzidine tetrachloride (DAB) sub-
strate (Sigma-Aldrich, St. Louis, MO, USA) in accord-
ance with the instructions of the manufacturer. A
second set of sections was incubated with a secondary
goat-anti-rabbit antibody Alexa 546 (Molecular Probes)
at a dilution of 1:1000. Finally, the sections were
counterstained with 4′,6-diamidino-2-phenylindole (DAPI)
(D9542; Sigma-Aldrich) diluted at 1:2000. Cop-GFP trans-
fected control cells functioned as positive controls. In the
negative control sections, the primary antibody was
omitted. During microscopy of all slices, the number
of cells with a positive signal was estimated subject-
ively (low/moderate/high numbers). Histology of AT-MSCs in cell culture
Labelled AT-MSCs could be successfully detected in cell
culture with fluorescence microscopy (Figs. 1, 3) and
with immunohistochemistry and immunofluorescence
by using DAB and Alexa 546, respectively (Fig. 3). Histological tracking of GFP-labelled AT-MSCs
With fluorescence microscopy (Fig. 4, 5) immunohis-
tochemistry and immunofluorescence (Fig. 5), high
numbers of AT-MSCs expressing GFP antigen were
detected at and near the site of injection 3, 5, 7 and
9 weeks after intralesional injection in all horses. At
visual inspection, there was a tendency of finding less
labelled AT-MSCs with increasing time after implant-
ation
in
sequential
samples
taken
from
different
horses, respectively (Fig. 4). SPIO particles incorpo-
rated into AT-MSCs were detected by use of Prussian
blue staining in horses 1, 2 and 4 (Fig. 6). Creation of lesions Horses 2 (left front) and 4 (both, right front > left front)
developed a cellulitis. This was accompanied by the devel-
opment of lameness, which started at 1 day after surgery
and persisted for 5 days in horse 2. In horse 4, lameness
started at 6 days after lesion creation and lasted for 2 days. Both horses received cefquinome for 7 days (1 mg/kg bwt
[intramuscularly]). GFP cells
Merge
GFP cells
Merge
# 1 cells
# 1 cells
anti-GFP-DAB
anti-GFP-546
20x
Fig. 3 Photomicrographs of GFP-labelled equine AT-MSCs from horse 1 in cell culture. In the upper row, GFP-fluorescence, anti-GFP
immunohistochemistry (DAB) and merged images are shown. In the lower row, GFP-fluorescence, anti-GFP immunofluorescence
(Alexa 546) and merged images of AT-MSCs (passage 6) are shown. Magnification: 20×. AT-MSC adipose tissue-derived mesenchymal
stromal cell, DAB diaminobenzidine tetrachloride, DAPI 4′,6-diamidino-2-phenylindole, GFP green fluorescent protein Fig. 3 Photomicrographs of GFP-labelled equine AT-MSCs from horse 1 in cell culture. In the upper row, GFP-fluorescence, anti-GFP
immunohistochemistry (DAB) and merged images are shown. In the lower row, GFP-fluorescence, anti-GFP immunofluorescence
(Alexa 546) and merged images of AT-MSCs (passage 6) are shown. Magnification: 20×. AT-MSC adipose tissue-derived mesenchymal
stromal cell, DAB diaminobenzidine tetrachloride, DAPI 4′,6-diamidino-2-phenylindole, GFP green fluorescent protein Page 7 of 12 Geburek et al. Stem Cell Research & Therapy (2016) 7:21 # 1
Dapi
GFP cells
Merge
Brightfield
# 2
3 weeks after
transplant
5 weeks after
transplant
# 4
9 weeks after
transplant
7 weeks after
transplant
# 3
Fig. 4 Photomicrographs of superficial digital flexor tendon lesions 3, 5, 7 and 9 weeks after transplantation of GFP-labelled autologous adipose
tissue-derived mesenchymal stromal cells. Bright field, DAPI nuclear stain and GFP-fluorescence and merged images taken from horses 1–4 are shown. Transplanted cells were positive in the cytoplasm for GFP. Magnification: 20×. DAPI 4′,6-diamidino-2-phenylindole, GFP green fluorescent protein Brightfield # 4 Fig. 4 Photomicrographs of superficial digital flexor tendon lesions 3, 5, 7 and 9 weeks after transplantation of GFP-labelled autologous adipose
tissue-derived mesenchymal stromal cells. Bright field, DAPI nuclear stain and GFP-fluorescence and merged images taken from horses 1–4 are shown. Transplanted cells were positive in the cytoplasm for GFP. Magnification: 20×. DAPI 4′,6-diamidino-2-phenylindole, GFP green fluorescent protein sequences to track SPIO-labelled AT-MSCs in vivo
over a period of at least 9 weeks. Creation of lesions It is further shown
that GFP-labelled AT-MSCs can be successfully de-
tected in and near surgically induced equine SDFT
lesions between 3 to 9 weeks after intralesional injection
by using fluorescence microscopy, immunofluorescence,
immunohistochemistry and Prussian blue staining. diffusely defined and markedly extended to the lateral
subcutis in T2* and T1 sequences (Fig. 7). Discussion
M i
fi di The results of the present study show the potential of
standing low-field MRI using T2*- and T1-weighted # 1
# 1
Dapi
GFP cells
anti-GFP-546
Merge
Brightfield
GFP cells
anti-GFP-DAB
Merge
20x
20x
Fig. 5 Photomicrographs of a superficial digital flexor tendon lesion 3 weeks after transplantation of GFP-labelled autologous adipose tissue-derived
mesenchymal stromal cells. In the upper row, bright field, GFP-fluorescence, anti-GFP immunohistochemistry (DAB) and merged (arrows: positive cells)
images are shown. In the lower row, DAPI nuclear stain, GFP-fluorescence, anti-GFP immunofluorescence (Alexa 546) and merged images (horse 1) are
shown. Approximately 50 % of the cells were positive for GFP in their cytoplasm. Magnification: 20×. DAB diaminobenzidine tetrachloride,
DAPI 4′,6-diamidino-2-phenylindole, GFP green fluorescent protein Fig. 5 Photomicrographs of a superficial digital flexor tendon lesion 3 weeks after transplantation of GFP-labelled autologous adipose tissue-derived
mesenchymal stromal cells. In the upper row, bright field, GFP-fluorescence, anti-GFP immunohistochemistry (DAB) and merged (arrows: positive cells)
images are shown. In the lower row, DAPI nuclear stain, GFP-fluorescence, anti-GFP immunofluorescence (Alexa 546) and merged images (horse 1) are
shown. Approximately 50 % of the cells were positive for GFP in their cytoplasm. Magnification: 20×. DAB diaminobenzidine tetrachloride,
DAPI 4′,6-diamidino-2-phenylindole, GFP green fluorescent protein Geburek et al. Stem Cell Research & Therapy (2016) 7:21 Page 8 of 12 D
D/1
C
C/1
10x
20x
10x
20x
B
B/1
# 2
# 4
# 3
SPIO labelled
SPIO labelled
SPIO labelled not SPIO labelled
A/1
20x
10x
A
# 1
Fig. 6 Photomicrographs of surgically created superficial digital flexor tendon lesions treated with autologous AT-MSCs and stained with Prussian blue. a, b, d Lesions treated with SPIO-labelled AT-MSCs (horses 1, 2 and 4). c Lesion treated with non-SPIO-labelled AT-MSCs (horse 3). Magnifications: 10×
(a-d) and 20× (A/1-D/1). AT-MSC adipose tissue-derived mesenchymal stromal cell, SPIO superparamagnetic iron oxide 10x
A
# 1 10x
B
# 2 B C
10x
# 3 C/1 C SPIO labelled not SP D
# 4 D/1 D Fig. 6 Photomicrographs of surgically created superficial digital flexor tendon lesions treated with autologous AT-MSCs and stained with Prussian blue. a, b, d Lesions treated with SPIO-labelled AT-MSCs (horses 1, 2 and 4). c Lesion treated with non-SPIO-labelled AT-MSCs (horse 3). Magnifications: 10×
(a-d) and 20× (A/1-D/1). AT-MSC adipose tissue-derived mesenchymal stromal cell, SPIO superparamagnetic iron oxide AT-MSCs versus MSCs from other sources equine tendinopathy [12]. Discussion
M i
fi di Results of the present study
prove the traceability of AT-MSCs labelled with GFP
near the injection site for up to at least 9 weeks (62 days). By contrast, in a different study, the number of equine
BM-MSCs decreased significantly after 10 days. At the
same time, equine ESCs were constantly traceable in
high numbers until 90 days after injection by using a la-
belling technique similar to the one in the present study
[10]. These findings demonstrate the existence of differ-
ences between MSCs from different tissue sources and
emphasize the necessity to research the fate of different
types of equine MSCs separately, dose-dependently and
for a period of time longer than in the present study. In a previous study, immunophenotyping of equine MSCs
showed that MSCs from different sources vary in their ex-
pression of MSC-defining antigens [22], suggesting that a
deliberate choice of the cell type is important for the treat-
ment of tendinopathy. In the present study, AT-MSCs
were used because comparative in vitro investigations on
the potential suitability for the treatment of tendinopathy
made obvious that AT-MSCs express extracellular matrix
proteins and tendon markers at significant rates, suggest-
ing an outstanding potential of adipose-derived MSCs for
the treatment of tendinopathy [11]. Up to now, data about cellular homing of AT-MSCs
were available for a period of merely 7 days after im-
plantation of the cells, which had been labelled with
quantum dots (nanocrystals) in a collagenase model of The number of cells injected in the present study
was relatively high and reflects current practice in
equine orthopaedics. In contrast to the high numbers Page 9 of 12 Page 9 of 12 Geburek et al. Stem Cell Research & Therapy (2016) 7:21 tendon-like tissue (i.e., a true regenerative effect via
engraftment and differentiation) or through modulatory
paracrine actions of the cells by the production of cyto-
kines and growth factors [25]. From the findings of the
present study, it can be concluded that cells remain at
the lesion site for a sufficiently long period after AT-
MSC treatment of equine tendinopathy and that both
pathways are possible. Reliability of the techniques b, d Signal intensity of the saline treated
lesion is increased in the contralateral SDFT, area indicated by
asterisk in b. a, b: T2*-weighted sequence, 47 days after
injection. c, d: T1-weighted sequence, 62 days after injection; horse
4. AT-MSC adipose tissue-derived mesenchymal stromal cell, SDFT
superficial digital flexor tendon, SPIO superparamagnetic iron oxide of GFP-positive AT-MSCs after 9 weeks during the
present investigation, consistent GFP expression of ovine
BM-MSCs could be detected at day 7 but no longer at day
14 after injection of 0.5 and 1 × 106 cells in a recent ovine
experimental tendinopathy study [23]. Discussion
M i
fi di This conclusion further supports
the clinical use of MSCs in horses with centrally located
tendinopathy of the SDFT and may be an explanatory
factor for the clinical observation that stem cell therapy
results in a significantly lower number of re-injuries than
other treatments for tendinopathy in the horse [6, 7, 26]. A
B
*
C
D
Fig. 7 Transverse magnetic resonance imaging images of SDFT
lesions treated with 10 × 106 SPIO-labelled AT-MSCs or saline. a, c
A focal, moderately demarcated hypointense area is evident in
and lateral to the AT-MSC-treated SDFT lesion, area indicated by
arrowheads in a. b, d Signal intensity of the saline treated
lesion is increased in the contralateral SDFT, area indicated by
asterisk in b. a, b: T2*-weighted sequence, 47 days after
injection. c, d: T1-weighted sequence, 62 days after injection; horse
4. AT-MSC adipose tissue-derived mesenchymal stromal cell, SDFT
superficial digital flexor tendon, SPIO superparamagnetic iron oxide A B
* A B Reliability of the techniques C D D C The transfection rate of cultured MSCs with reporter
genes expressing GFP was approximately 99 % in the
cells used for injection, as shown by flow cytometric
analysis during passage 0. Fluorescence microscopy dur-
ing passage 1 and flow cytometric analysis during pas-
sage 2 showed that the percentage of transfected MSCs
had a tendency to decrease during early passages. This
finding agrees with previous observations and is poten-
tially caused by transgene silencing caused by epigenetic
downregulation of transgenes leading to mosaic expres-
sion patterns [27, 28]. However, lentiviral vectors encod-
ing GFP have been shown to lack significant negative
effects on survival and differentiation potential of MSCs
in vitro [28]. The transfection of cultured MSCs with re-
porter genes expressing GFP was successful for tracking
AT-MSCs up to 9 weeks after implantation, which
proves the suitability of this technique for AT-MSCs
implanted into tendon defects as previously described
for BM-MSCs and ESCs [10]. The labelling of MSCs
with GFP by viral transfection is an established method
in experimental animal studies [23, 29, 30]. The detec-
tion of GFP under fluorescence microscopy might be
impaired by natural fluorescence of cell metabolites and
structural components such as collagen in tissue speci-
men [31]. This phenomenon referred to as “autofluores-
cence” did not impair interpretation in the present study
significantly as verified by immunohistochemical stain-
ing and immunofluorescence of GFP-expressing cells
using DAB and Alexa 546 and by counterstaining of cell
nuclei with DAPI. Fig. 7 Transverse magnetic resonance imaging images of SDFT
lesions treated with 10 × 106 SPIO-labelled AT-MSCs or saline. a, c
A focal, moderately demarcated hypointense area is evident in
and lateral to the AT-MSC-treated SDFT lesion, area indicated by
arrowheads in a. b, d Signal intensity of the saline treated
lesion is increased in the contralateral SDFT, area indicated by
asterisk in b. a, b: T2*-weighted sequence, 47 days after
injection. c, d: T1-weighted sequence, 62 days after injection; horse
4. AT-MSC adipose tissue-derived mesenchymal stromal cell, SDFT
superficial digital flexor tendon, SPIO superparamagnetic iron oxide Fig. 7 Transverse magnetic resonance imaging images of SDFT
lesions treated with 10 × 106 SPIO-labelled AT-MSCs or saline. a, c
A focal, moderately demarcated hypointense area is evident in
and lateral to the AT-MSC-treated SDFT lesion, area indicated by
arrowheads in a. Relevance of finding In the present study, SPIO-labelled AT-MSCs could be
detected with MRI in the lesion and its lateral periphery
up to 9 weeks after implantation. The presence of SPIO
particles was proved successfully with Prussian blue
staining of tendon tissue post-mortem. Labelling of
MSCs with SPIO particles has been previously used to
track MSCs successfully in laboratory rodents and sheep
[23, 32, 33]; the procedure affects their viability to some
extent but insignificantly, although their proliferative The tendency of finding fewer labelled AT-MSCs at
visual inspection with increasing time after implantation
in the sequential samples taken from different horses
suggests a decrease of the cells over time. Nevertheless,
high numbers of cells were still present in and near the
lesion site for up to 9 weeks after treatment. It has been
postulated that the beneficial effects of MSCs on tendon
healing observed clinically [24] and experimentally [3] in
studies may be the result of either de novo formation of Geburek et al. Stem Cell Research & Therapy (2016) 7:21 Page 10 of 12 Page 10 of 12 Page 10 of 12 capacity may be decreased [16, 17, 23, 32]. In a recent
equine study, SPIO-labelled BM-MSCs could be suc-
cessfully detected in cadaveric SDFTs by using 1.5-
Tesla MRI [16]. The present study shows that SPIO
labelling is also a practicable technique to track AT-
MSCs injected in surgically created tendon lesions
with 0.27-Tesla MRI in live horses in T2*-weighted
sequences with the aid of the susceptibility artefact. Detection of SPIO particles was also successful in
T1-weighted sequences, accepting a less distinct de-
marcation of the intact tendon tissue. The use of
ultra-small SPIO particles might have increased the
contrast in T1-weighted sequences. Alternative se-
quences, potentially appropriate to monitor SPIO-
particles
(e.g.,
3DT1),
were
not
available
for
the
standing low-field MRI used in the present study. An-
gulation of the SDFTs relative to the magnetic field,
using the magic angle effect, would probably have
further improved MRI of SPIO particles [33]. Vaguely
demarcated hypointense areas in the subcutis at the
injection site helped to identify the sites of injection,
especially
in
T1-weighted
sequences. These
signal
voids are a potential sign of migration of the injected
MSCs or of reflux of the cell suspension during or
after injection. Although no resistance of the syringe
plunger was encountered during injection, alternative
injection techniques should be considered to avoid
reflux from tendon lesions. Relevance of finding influence tendon metabolism: oxytetracycline showed
in vitro inhibition of suspensory ligament myofibroblast
contractility [38], and oral doxycycline administration
leads
to
inhibition
of
matrix
metalloproteinase-13
(MMP-13) in rat tendons [39]. Cellulitis was restricted to
the subcutaneous area and there were no indications that
it extended into the created core lesion. Hence, no direct
effect on migration behaviour of the cells could be ex-
pected. Nor are there indications that the cellulitis has
hampered the modalities used in the present study to
track implanted cells in any way. Limitations The present study’s crucial limitation was that the
number of labelled cells was not counted but deter-
mined semi-quantitatively in post-mortem specimen. The fact that in the present study 10 × 106 AT-MSCs
were implanted but that Guest et al. [10] injected 1 ×
106 BM-MSCs or ESCs might have influenced the re-
sults. This holds true also for the use of different
models of tendinopathy in the present compared with
other studies [10, 12]. Only a small number of horses
were included in the present pilot study, and a stag-
gered approach was chosen to monitor the presence
of AT-MSCs over time. Therefore, the potential im-
pact of inter-individual variations (e.g., age, gender
and local infection) on the outcome cannot be deter-
mined on the basis of the present results. Tissue from
the opposite front-limb SDFT was not examined his-
tologically in the present study, but Carvalho et al. [12] could not detect AT-MSCs in the contralateral
SDFT 7 days after intralesional injection of the ipsi-
lateral SDFT. Histological tracking of MSCs in the re-
gional lymph node (Lnn. axillares superficiales) using
the techniques presented here should be included in
future studies to further characterize AT-MSC distri-
bution after injection. Another limitation is that the
signal intensity change was not quantified objectively
on MRI images. The loss of signal intensity may be
objectified and a threshold may be established. The present study proves that co-labelling of equine
AT-MSCs with a lentiviral copGFP promotor and SPIO
particles is feasible. Whether the procedure affects the
biological activity of the cells (and, if so, to what extent)
remains uncertain [23]. Alternative techniques to track MSCs are labelling
with nanocrystals, which are resistant to metabolic
degradation and have few cytotoxic effects [34, 35], and
with technetium-99 hexamethyl propylene amine oxime,
which allows detection of cells by nuclear scintigraphy
but only for 24 h after administration [36]. Both tech-
niques have been used successfully in experimentally
induced equine tendon lesions [12, 37]. Competing interests HTMvS is the inventor of the ultrasonographic tissue characterization device. He has not given any financial support for this study and has no financial
interests in relation to this study. The other authors declare that they have
no competing interests. 11. Burk J, Gittel C, Heller S, Pfeiffer B, Paebst F, Ahrberg AB, et al. Gene
expression of tendon markers in mesenchymal stromal cells derived from
different sources. BMC Res Notes. 2014;7:826. Authors’ contributions 12. Carvalho AM, Yamada AL, Golim MA, Alvarez LE, Hussni CA, Alves AL. Evaluation of mesenchymal stem cell migration after equine tendonitis
therapy. Equine Vet J. 2014;46:635–8. FG had the idea of performing the study, designed the study and
co-ordinated it. He participated in the collection of clinical, ultrasonographic
and histologic data and their analyses and contributed to the interpretation
of MRI data and wrote and drafted the manuscript. KM collected the clinical,
ultrasonographic, MRI and histologic data and participated in their analyses
and revised the manuscript critically. SC performed culture and labelling of
the AT-MSCs, contributed to interpretation of the histologic data and revised
the manuscript critically. MH evaluated MRI data and revised the manuscript
critically. UW contributed to the coordination of the study and to the
interpretation of MRI data and revised the manuscript critically. HTMvS
participated in the design and coordination of the study and revised the
manuscript critically. RvW participated in the design and coordination of the
study and revised the manuscript critically. TS instructed and supervised the
histologic examinations and revised the manuscript critically. PMS participated
in the design of the study, contributed to the analyses of the data and revised
the manuscript critically. All authors read and approved the manuscript for
publication. 13. Wang YX, Hussain SM, Krestin GP. Superparamagnetic iron oxide contrast
agents: physicochemical characteristics and applications in MR imaging. Eur Radiol. 2001;11:2319–31. 14. Julke H, Veit C, Ribitsch I, Brehm W, Ludewig E, Delling U. Comparative
Labeling of Equine and Ovine Multipotent Stromal Cells With
Superparamagnetic Iron Oxide Particles for Magnetic Resonance Imaging
In Vitro. Cell Transplant. 2015;24:1111–25. 15. Wang HH, Wang YXJ, Leung KCF, Au DWT, Xuan SH, Chak CP, et al. Durable
Mesenchymal Stem Cell Labelling by Using Polyhedral Superparamagnetic
Iron Oxide Nanoparticles. Chem-Eur J. 2009;15(45):12417–25. 16. Bourzac CA, Koenig JB, Link KA, Nykamp SG, Koch TG. Evaluation of ultrasmall
superparamagnetic iron oxide contrast agent labeling of equine cord blood
and bone marrow mesenchymal stromal cells. Am J Vet Res. 2014;75:1010–7. 17. Farrell E, Wielopolski P, Pavljasevic P, van Tiel S, Jahr H, Verhaar J, et al. Effects
of iron oxide incorporation for long term cell tracking on MSC differentiation
in vitro and in vivo. Biochem Biophys Res Commun. 2008;369:1076–81. Author details
1 1Clinic for Horses, University of Veterinary Medicine Hannover, Foundation,
Bünteweg 9, 30559 Hannover, Germany. 2Pferdeklink Kirchheim, Nürtinger
Straße 200, 73230 Kirchheim unter Teck, Germany. 3P.O. Box 1243, 72072
Tübingen, Germany. 4Department of Equine Sciences, Faculty of Veterinary
Medicine, Utrecht University, Yalelaan 112, 3584 CM Utrecht, The
Netherlands. 5Institute for Anatomy and Cell Biology, University of
Heidelberg, Im Neuenheimer Feld 307, 69120 Heidelberg, Germany. 21. Bosch G, van Schie HT, de Groot MW, Cadby JA, van de Lest CH, Barneveld A,
et al. Effects of platelet-rich plasma on the quality of repair of mechanically
induced core lesions in equine superficial digital flexor tendons: a
placebo-controlled experimental study. J Orthop Res. 2010;28:211–7. 22. Paebst F, Piehler D, Brehm W, Heller S, Schroeck C, Tarnok A, et al. Comparative Immunophenotyping of Equine Multipotent Mesenchymal
Stromal Cells: An Approach Toward a Standardized Definition. Cytom Part A. 2014;85A:678–87. Received: 27 August 2015 Revised: 16 December 2015
Accepted: 14 January 2016 Received: 27 August 2015 Revised: 16 December 2015
Accepted: 14 January 2016 23. Scharf A, Holmes S, Thoresen M, Mumaw J, Stumpf A, Peroni J. Superparamagnetic iron oxide nanoparticles as a means to track
mesenchymal stem cells in a large animal model of tendon injury. Contrast Media Mol Imaging. 2015;10:388–97. Cellulitis Conclusively, standing low-field MRI has the potential
to track SPIO-labelled AT-MSCs in surgically induced
SDFT lesions for up to 9 weeks in vivo, as demon-
strated by the detection of large numbers of labelled
cells with histology, immunofluorescence and immu-
nohistochemistry
in
post-mortem
specimen
of
the
lesions. Injection techniques have to be chosen delib-
erately to avoid reflux of the cell substrate injected. In future dose-dependent controlled clinical trials,
numbers of cells retrieved in the tendons should be
quantified and horses should be monitored for a lon-
ger period of time. Horses 2 and 4 developed mild cellulitis after surgical
induction of the lesions, the former in the limb
treated with SPIO-labelled AT-MSC, the latter in both
limbs but predominantly in the control limb. This
complication most likely can be attributed to the
surgical procedure or the aftercare during the days
after surgery (or both), as clinical signs started before
injection of AT-MSCs. Metaphylactic treatment with
antimicrobials might have decreased the risk. However,
a deliberate choice was made not to do this as there is
evidence that some antimicrobials have the potential to Page 11 of 12 Page 11 of 12 Page 11 of 12 Geburek et al. Stem Cell Research & Therapy (2016) 7:21 Geburek et al. Stem Cell Research & Therapy (2016) 7:21 Geburek et al. Stem Cell Research & Therapy (2016) 7:21 Abbreviations enriched autologous adipose-derived mesenchymal stem cells: a clinical
study. Regen Med. 2009;4:Suppl. 2. S21. enriched autologous adipose-derived mesenchymal stem cells: a clinical
study. Regen Med. 2009;4:Suppl. 2. S21. enriched autologous adipose-derived mesenchymal stem cells: a clinical
study. Regen Med. 2009;4:Suppl. 2. S21. AT-MSC: Adipose tissue-derived mesenchymal stromal cell; BM-MSC: Bone
marrow-derived mesenchymal stromal cell; bwt: Body weight;
DAB: Diaminobenzidine tetrachloride; DAPI: 4′,6-diamidino-2-phenylindole;
ESC: Embryonic stem cell; FA: Flip angle; GFP: Green fluorescent protein;
IV: Intravenously; MRI: Magnetic resonance imaging; MSC: Mesenchymal stromal
cell; PBS: Phosphate-buffered saline; SDFT: superficial digital flexor tendon;
SPIO: Superparamagnetic iron oxide; TE: Echo time; TR: Relaxation time. 7. Dahlgren LA. Fat derived mesenchymal stem cells for equine tendon repair. Regen Med. 2009;4:Suppl. 2. S14. 7. Dahlgren LA. Fat derived mesenchymal stem cells for equine tendon repair
Regen Med. 2009;4:Suppl. 2. S14. 8. Prockop DJ, Kota DJ, Bazhanov N, Reger RL. Evolving paradigms for repair of
tissues by adult stem/progenitor cells (MSCs). J Cell Mol Med. 2010;14:2190–9. 9. Guest DJ, Smith MR, Allen WR. Monitoring the fate of autologous and
allogeneic mesenchymal progenitor cells injected into the superficial digital
flexor tendon of horses: preliminary study. Equine Vet J. 2008;40:178–81. 10. Guest DJ, Smith MR, Allen WR. Equine embryonic stem-like cells and
mesenchymal stromal cells have different survival rates and migration
patterns following their injection into damaged superficial digital flexor
tendon. Equine Vet J. 2010;42:636–42. Acknowledgements
Th
h
h
k D
A 18. Li YG, Wei JN, Lu J, Wu XT, Teng GJ. Labeling and tracing of bone marrow
mesenchymal stem cells for tendon-to-bone tunnel healing. Knee Surg
Sports Traumatol Arthrosc. 2011;19:2153–8. The authors thank Drs. Astrid v. Velsen-Zerweck, Gerco Bosch and Florent David
for their much appreciated help throughout the study period and Monika
Langlotz, of ZMBH (Zentrum für Molekulare Biologie der Universität Heidelberg),
Flow Cytometry & FACS Core Facility, for providing flow cytometric analyses. 19. Little D, Schramme MC. Ultrasonographic and MRI evaluation of a novel
tendonitis model in the horse. Vet Surg. 2006;35:E15. 19. Little D, Schramme MC. Ultrasonographic and MRI evaluation of a novel
tendonitis model in the horse. Vet Surg. 2006;35:E15. 20. Schramme M, Hunter S, Campbell N, Blikslager A, Smith R. A surgical
tendonitis model in horses: Techinque, clinical, ultrasonographic and
histological characterisation. Vet Comp Orthopaed. 2010;23:231–9. 20. Schramme M, Hunter S, Campbell N, Blikslager A, Smith R. A surgical
tendonitis model in horses: Techinque, clinical, ultrasonographic and
histological characterisation. Vet Comp Orthopaed. 2010;23:231–9. 1.
Smith R, Young N, Dudhia J, Kasashima Y, Clegg P, Goodship A.
Effectiveness of bone-marrow-derived mesenchymal progenitor cells for
naturally occurring tendinopathy in the horse. Regen Med. 2009;4 Suppl 2:S25.
2.
Nixon AJ, Dahlgren LA, Haupt JL, Yeager AE, Ward DL. Effect of adipose-
derived nucleated cell fractions on tendon repair in horses with
collagenase-induced tendinitis. Am J Vet Res. 2008;69:928–37.
3.
Carvalho A de M, Badial PR, Álvarez LE, Yamada AL, Borges AS, Deffune E,
et al. Equine tendonitis therapy using mesenchymal stem cells and platelet
concentrates: a randomized controlled trial. Stem Cell Res Ther. 2013;4:85.
4.
Conze P, van Schie HT, Weeren RV, Staszyk C, Conrad S, Skutella T, et al.
Effect of autologous adipose tissue-derived mesenchymal stem cells on
neovascularization of artificial equine tendon lesions. Regen Med. 2014;9:743–57.
5.
Carvalho AD, Alves ALG, de Oliveira PGG, Alvarez LEC, Amorim RL, Hussni CA,
et al. Use of Adipose Tissue-Derived Mesenchymal Stem Cells for Experimental
Tendinitis Therapy in Equines. J Equine Vet Sci. 2011;31:26–34.
6.
Leppänen M, Heikkilä P, Katiskalahti T, Tulamo RM. Follow up of recovery of
equine tendon & ligament injuries 18–24 months after treatment with References 1. Smith R, Young N, Dudhia J, Kasashima Y, Clegg P, Goodship A. Effectiveness of bone-marrow-derived mesenchymal progenitor cells for
naturally occurring tendinopathy in the horse. Regen Med. 2009;4 Suppl 2:S25. 2. Nixon AJ, Dahlgren LA, Haupt JL, Yeager AE, Ward DL. Effect of adipose-
derived nucleated cell fractions on tendon repair in horses with
collagenase-induced tendinitis. Am J Vet Res. 2008;69:928–37. 3. Carvalho A de M, Badial PR, Álvarez LE, Yamada AL, Borges AS, Deffune E,
et al. Equine tendonitis therapy using mesenchymal stem cells and platelet
concentrates: a randomized controlled trial. Stem Cell Res Ther. 2013;4:85. 4. Conze P, van Schie HT, Weeren RV, Staszyk C, Conrad S, Skutella T, et al. Effect of autologous adipose tissue-derived mesenchymal stem cells on
neovascularization of artificial equine tendon lesions. Regen Med. 2014;9:743–57. 5. Carvalho AD, Alves ALG, de Oliveira PGG, Alvarez LEC, Amorim RL, Hussni CA,
et al. Use of Adipose Tissue-Derived Mesenchymal Stem Cells for Experimental
Tendinitis Therapy in Equines. J Equine Vet Sci. 2011;31:26–34. 6. Leppänen M, Heikkilä P, Katiskalahti T, Tulamo RM. Follow up of recovery of
equine tendon & ligament injuries 18–24 months after treatment with 1. Smith R, Young N, Dudhia J, Kasashima Y, Clegg P, Goodship A. Effectiveness of bone-marrow-derived mesenchymal progenitor cells for
naturally occurring tendinopathy in the horse. Regen Med. 2009;4 Suppl 2:S25. 2. Nixon AJ, Dahlgren LA, Haupt JL, Yeager AE, Ward DL. Effect of adipose-
derived nucleated cell fractions on tendon repair in horses with
collagenase-induced tendinitis. Am J Vet Res. 2008;69:928–37. 3. Carvalho A de M, Badial PR, Álvarez LE, Yamada AL, Borges AS, Deffune E,
et al. Equine tendonitis therapy using mesenchymal stem cells and platelet
concentrates: a randomized controlled trial. Stem Cell Res Ther. 2013;4:85. 4. Conze P, van Schie HT, Weeren RV, Staszyk C, Conrad S, Skutella T, et al. Effect of autologous adipose tissue-derived mesenchymal stem cells on
neovascularization of artificial equine tendon lesions. Regen Med. 2014;9:743–57. 5. Carvalho AD, Alves ALG, de Oliveira PGG, Alvarez LEC, Amorim RL, Hussni CA,
et al. Use of Adipose Tissue-Derived Mesenchymal Stem Cells for Experimental
Tendinitis Therapy in Equines. J Equine Vet Sci. 2011;31:26–34. 6. Leppänen M, Heikkilä P, Katiskalahti T, Tulamo RM. Follow up of recovery of
equine tendon & ligament injuries 18–24 months after treatment with 1. Smith R, Young N, Dudhia J, Kasashima Y, Clegg P, Goodship A. References Effectiveness of bone-marrow-derived mesenchymal progenitor cells for
naturally occurring tendinopathy in the horse. Regen Med. 2009;4 Suppl 2:S25 1. Smith R, Young N, Dudhia J, Kasashima Y, Clegg P, Goodship A. Effectiveness of bone-marrow-derived mesenchymal progenitor cells for
naturally occurring tendinopathy in the horse. Regen Med. 2009;4 Suppl 2:S25 24. Smith RK, Werling NJ, Dakin SG, Alam R, Goodship AE, Dudhia J. Beneficial
effects of autologous bone marrow-derived mesenchymal stem cells in
naturally occurring tendinopathy. PLoS One. 2013;8:e75697. 2. Nixon AJ, Dahlgren LA, Haupt JL, Yeager AE, Ward DL. Effect of adipose-
derived nucleated cell fractions on tendon repair in horses with
collagenase-induced tendinitis. Am J Vet Res. 2008;69:928–37. 25. Caplan AI. Why are MSCs therapeutic? New data: new insight. J Pathol. 2009;217:318–24. 26. Godwin EE, Young NJ, Dudhia J, Beamish IC, Smith RK. Implantation of bone
marrow-derived mesenchymal stem cells demonstrates improved outcome
in horses with overstrain injury of the superficial digital flexor tendon. Equine Vet J. 2012;44:25–32. 27. Kaufman WL, Kocman I, Agrawal V, Rahn HP, Besser D, Gossen M. Homogeneity and persistence of transgene expression by omitting
antibiotic selection in cell line isolation. Nucleic Acids Res. 2008;36(17):e111. 28. McGinley L, McMahon J, Strappe P, Barry F, Murphy M, O’Toole D, et al. Lentiviral vector mediated modification of mesenchymal stem cells &
enhanced survival in an in vitro model of ischaemia. Stem Cell Res Ther. 2011;2:12. Page 12 of 12 29. Czernik M, Fidanza A, Sardi M, Galli C, Brunetti D, Malatesta D, et al. Differentiation potential and GFP labeling of sheep bone marrow-derived
mesenchymal stem cells. J Cell Biochem. 2013;114:134–43. 30. Colosimo A, Curini V, Russo V, Mauro A, Bernabo N, Marchisio M, et al. Characterization, GFP gene Nucleofection, and allotransplantation in injured
tendons of ovine amniotic fluid-derived stem cells. Cell Transplant. 2013;22:99–117. 31. Lin CS, Xin ZC, Dai J, Lue TF. Commonly used mesenchymal stem cell
markers and tracking labels: Limitations and challenges. Histol Histopathol. 2013;28:1109–16. 32. Wang L, Deng JX, Wang J, Xiang B, Yang TH, Gruwel M, et al. Superparamagnetic iron oxide does not affect the viability and function of
adipose-derived stem cells, and superparamagnetic iron oxide-enhanced
magnetic resonance imaging identifies viable cells. Magn Reson Imaging. 2009;27:108–19. 33. Yang Y, Zhang J, Qian Y, Dong S, Huang H, Boada FE, et al. Superparamagnetic iron oxide is suitable to label tendon stem cells and
track them in vivo with MR imaging. Ann Biomed Eng. 2013;41:2109–19. Geburek et al. Stem Cell Research & Therapy (2016) 7:21 References 34. Collins MC, Gunst PR, Cascio WE, Kypson AP, Muller-Borer BJ. Labeling and
imaging mesenchymal stem cells with quantum dots. Methods Mol Biol. 2012;906:199–210. 35. Muller-Borer BJ, Collins MC, Gunst PR, Cascio WE, Kypson AP. Quantum dot
labeling of mesenchymal stem cells. J Nanobiotechnol. 2007;5:9. 36. Sole A, Spriet M, Galuppo LD, Padgett KA, Borjesson DL, Wisner ER, et al. Scintigraphic evaluation of intra-arterial and intravenous regional limb
perfusion of allogeneic bone marrow-derived mesenchymal stem cells in
the normal equine distal limb using (99 m) Tc-HMPAO. Equine Vet J. 2012;44:594–9. 37. Sole A, Spriet M, Padgett KA, Vaughan B, Galuppo LD, Borjesson DL, et al. Distribution and persistence of technetium-99 hexamethyl propylene amine
oxime-labelled bone marrow-derived mesenchymal stem cells in
experimentally induced tendon lesions after intratendinous injection and
regional perfusion of the equine distal limb. Equine Vet J. 2013;45:726–31. 38. Arnoczky SP, Lavagnino M, Gardner KL, Tian T, Vaupel ZM, Stick JA. In vitro
effects of oxytetracycline on matrix metalloproteinase-1 mRNA expression
and on collagen gel contraction by cultured myofibroblasts obtained from
the accessory ligament of foals. Am J Vet Res. 2004;65:491–6. 39. Bedi A, Fox AJ, Kovacevic D, Deng XH, Warren RF, Rodeo SA. Doxycycline-
mediated inhibition of matrix metalloproteinases improves healing after
rotator cuff repair. Am J Sports Med. 2010;38:308–17. • We accept pre-submission inquiries
• Our selector tool helps you to find the most relevant journal
• We provide round the clock customer support
• Convenient online submission
• Thorough peer review
• Inclusion in PubMed and all major indexing services
• Maximum visibility for your research
Submit your manuscript at
www.biomedcentral.com/submit
Submit your next manuscript to BioMed Central
and we will help you at every step: Submit your next manuscript to BioMed Central
and we will help you at every step: • We accept pre-submission inquiries
• Our selector tool helps you to find the most relevant journal
• We provide round the clock customer support
• Convenient online submission
• Thorough peer review
• Inclusion in PubMed and all major indexing services
• Maximum visibility for your research
Submit your manuscript at
www.biomedcentral.com/submit
Submit your next manuscript to BioMed Central
and we will help you at every step:
|
https://openalex.org/W3129179030
|
https://www.frontiersin.org/articles/10.3389/fcvm.2020.621149/pdf
|
English
| null |
Early Aortic Valve Replacement vs. Conservative Management in Asymptomatic Severe Aortic Stenosis Patients With Preserved Ejection Fraction: A Meta-Analysis
|
Frontiers in cardiovascular medicine
| 2,021
|
cc-by
| 6,248
|
Early Aortic Valve Replacement vs.
Conservative Management in
Asymptomatic Severe Aortic
Stenosis Patients With Preserved
Ejection Fraction: A Meta-Analysis
Tan Yuan 1†, Yi Lu 1†, Chang Bian 1* and Zhejun Cai 1,2*
1 Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China,
2 Jiaxing Key Laboratory of Cardiac Rehabilitation, Jiaxing, China Tan Yuan 1†, Yi Lu 1†, Chang Bian 1* and Zhejun Cai 1,2* 1 Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China,
2 Jiaxing Key Laboratory of Cardiac Rehabilitation, Jiaxing, China Background: Aortic stenosis (AS) is the most common valvular disease in developed
countries. Until now, the specific timing of intervention for asymptomatic patients with
severe aortic stenosis and preserved ejection fraction remains controversial. Methods: A systematic search of four databases (Pubmed, Web of science, Cochrane
library, Embase) was conducted. Studies of asymptomatic patients with severe AS or
very severe AS and preserved left ventricular ejection fraction underwent early aortic
valve replacement (AVR) or conservative care were included. The end points included
all-cause mortality, cardiac mortality, and non-cardiac mortality. Edited by:
Felix Jansen,
University Hospital Bonn, Germany
Reviewed by:
Francesco Pollari,
Nürnberg Hospital, Germany
Florian Kahles,
University Hospital RWTH
Aachen, Germany
*Correspondence:
Zhejun Cai
caizhejun@zju.edu.cn
Chang Bian
bianchang@zju.edu.cn
†These authors have contributed
equally to this work Edited by:
Felix Jansen,
University Hospital Bonn, Germany Edited by:
Felix Jansen,
University Hospital Bonn, Germany Reviewed by:
Francesco Pollari,
Nürnberg Hospital, Germany
Florian Kahles,
University Hospital RWTH
Aachen, Germany Results: Four eligible studies were identified with a total of 1,249 participants. Compared
to conservative management, patients who underwent early AVR were associated with
lower all-cause mortality, cardiac mortality, and non-cardiac mortality rate (OR 0.16, 95%
CI 0.09–0.31, P < 0.00001; OR 0.12, 95% CI 0.02–0.62, P = 0.01; OR 0.36, 95% CI
0.21–0.63, P = 0.0003, respectively). *Correspondence:
Zhejun Cai
caizhejun@zju.edu.cn
Chang Bian
bianchang@zju.edu.cn Conclusions:
Early AVR is preferable for asymptomatic severe AS patients with
preserved ejection fraction. Conclusions:
Early AVR is preferable for asymptomatic severe AS patients with
preserved ejection fraction. †These authors have contributed
equally to this work Keywords: asymptomatic, aortic stenosis, aortic valve replacement, conservative treatment, preserved
ejection fraction Specialty section:
This article was submitted to
Heart Valve Disease,
a section of the journal
Frontiers in Cardiovascular Medicine INTRODUCTION Aortic stenosis (AS) is the most common valvular disease in developed countries, which affects 5%
of population >65 years and 3% of population over 75 (1–3). Degenerative process is the major
etiology of AS, and ultimately leads to the valve remodeling and systemic blood flow restriction (4). The onset of symptoms (angina, dyspnea on exertion, and syncope) heralds a poor prognosis (5). For symptomatic AS patients, the annual mortality is close to 25% and the average survival time is
only 2–3 years (6). Therefore, aortic valve replacement (AVR), either surgical or interventional, is
strongly recommended, which is the current only feasible treatment for symptomatic AS (7, 8). Received: 25 October 2020
Accepted: 29 December 2020
Published: 03 February 2021 SYSTEMATIC REVIEW
published: 03 February 2021
doi: 10.3389/fcvm.2020.621149 PATIENTS AND METHODS The
review
was
reported
according
to
the
Preferred
Reporting Items for Systematic Reviews and Meta-Analyses
statement standards. Data Extraction and Risk of Bias in
Included Studies Two independent authors extracted the relevant data. The
extracted data included: (1) time, region and design; (2) study
period; (3) follow-up period; (4) number of patients; (5) mean age
and gender ratio of participants; and (6) LVEF, aortic valve area. Two independent authors extracted the relevant data. The
extracted data included: (1) time, region and design; (2) study
period; (3) follow-up period; (4) number of patients; (5) mean age
and gender ratio of participants; and (6) LVEF, aortic valve area. Two independent reviewers assessed the risk of bias among
included RCT trials by Cochrane Risk of Bias tool. The risk of
bias in included non-RCT studies was assessed by the Newcastle
Ottawa scale. No disagreements arose in the quality assessment. Quality assessment of all included studies indicated low risk
of bias. The overall risk of bias was graded as low risk. The
results are enclosed as Table 1, Figure 1. Publication bias was
assessed using funnel plots (Figure 2), which showed no evidence
of publication bias. Eligibility Criteria and Study Selection It had been reported that operative mortality of isolated AVR
for AS was 1–3% in patients <70 years old and 3–8% in
senior patients (14). According to the current guidelines, AVR
is recommended for asymptomatic AS patients with reduced left
ventricular ejection fraction (LVEF) (7). Eligibility Criteria and Study Selection
We included both randomized controlled trials (RCTs) and
non-randomized studies if they met the following criteria: (1)
patients with severe AS or very severe AS [severe AS was
defined as an aortic valve area ≤1 cm2 or peak aortic velocity
≥4 m/s or mean transaortic pressure gradient ≥40 mmHg;
very severe AS was defined as an aortic-valve area of ≤0.75
cm2 with either an aortic jet velocity of ≥4.5 m/s or a mean
transaortic gradient of ≥50 mmHg]; (2) asymptomatic (without
symptoms like exertional angina pectoris, syncope, exertional
dyspnea, etc.); (3) LVEF ≥50% or preserved LVEF (LVEF was
assessed by transthoracic echocardiography); and (4) included
the outcomes of patients underwent early AVR procedure
and patients received conservative care (early AVR procedure
was defined as intervention before the onset of symptoms or
declined LVEF). We excluded abstracts, reviews, case reports,
meeting abstracts, and editorial material. Eligibility screening
was conducted with a two-step strategy (title/abstract screening
and full-text screening). Two independent reviewers screened all
potentially eligible studies. On the other hand, treatment for asymptomatic severe AS
with preserved LVEF is still debatable. The recent guidelines
suggest a “watching waiting” strategy for the remaining
majority of asymptomatic patients (7). This recommendation was
based on non-randomized studies (12, 15) with low evidence
levels (16). Several recent studies reported that early AVR
for severe asymptomatic AS was associated lower mortality
and hospitalization for heart failure at 5-year of follow-up
with improved long-term outcomes (13). To facilitate clinical
decision-making, we conducted this meta-analysis to compare
the outcomes of early AVR and conservative strategy in
asymptomatic AS patients with preserved LVEF. Searching Strategy We searched four databases: Pubmed, Web of Science, Embase,
and Cochrane library. The last search was performed on July
29, 2020. We used search terms as follows: “asymptomatic” and
“aortic stenosis”. There were no language and year of publication
constraints in literature search. The detailed searching strategy is
provided in the online Supplementary File. Two independent reviewers assessed the risk of bias among
included RCT trials by Cochrane Risk of Bias tool. The risk of
bias in included non-RCT studies was assessed by the Newcastle
Ottawa scale. No disagreements arose in the quality assessment. Quality assessment of all included studies indicated low risk
of bias. The overall risk of bias was graded as low risk. The
results are enclosed as Table 1, Figure 1. Publication bias was
assessed using funnel plots (Figure 2), which showed no evidence
of publication bias. TABLE 1 | Newcastle-Ottawa scale. Study
Selection
Comparability
Outcomes
Quality score
Kang
⋆⋆⋆⋆
⋆⋆
⋆⋆
8
Kim
⋆⋆⋆⋆
⋆⋆
⋆⋆
8
Bohbot
⋆⋆⋆⋆
⋆⋆
⋆⋆
8
FIGURE 1 | Bias assessment for included RCT trials. g
results are enclosed as Table 1, Figure 1. Publication bias was
assessed using funnel plots (Figure 2), which showed no evidence
of publication bias. Data Items
We
sought
data
according
to
the
following
PICOS:
P
(Population), patients with asymptomatic severe asymptomatic Citation: Yuan T, Lu Y, Bian C and Cai Z (2021)
Early Aortic Valve Replacement vs. Conservative Management in
Asymptomatic Severe Aortic Stenosis
Patients With Preserved Ejection
Fraction: A Meta-Analysis. Front. Cardiovasc. Med. 7:621149. doi: 10.3389/fcvm.2020.621149 However, ∼50% of patients with severe AS are asymptomatic at the time of diagnosis (3, 9). The mortality in asymptomatic patients without surgery ranges widely across the studies and the
cumulative 5-year all-cause death incidences is up to 62% (10–13). However, the potential benefit of
AVR for asymptomatic patients with severe AS may not outweigh the operative complications (14). February 2021 | Volume 7 | Article 621149 Frontiers in Cardiovascular Medicine | www.frontiersin.org Early Aortic Valve Replacement Yuan et al. Data Items We
sought
data
according
to
the
following
PICOS:
P
(Population), patients with asymptomatic severe asymptomatic FIGURE 1 | Bias assessment for included RCT trials. FIGURE 1 | Bias assessment for included RCT trials. February 2021 | Volume 7 | Article 621149 2 Early Aortic Valve Replacement Yuan et al. AS (LVEF ≥50%); I (Intervention), early AVR; C (Comparison),
conservative strategy; O (Outcome), all-cause mortality, cardiac
mortality, and non-cardiac mortality; and S (Study type), RCT,
and observational studies. meta-analysis compared the prognosis of asymptomatic AS
patients with preserved EF underwent early AVR procedure with
those who received conservative care strategy. End Points First author
Year
Study design
Region(s)
Study period
Number of
patients
Follow-up
(months)
Kang
2020
RCT
South Korea
2010–2015
145
74.4 (60–88.8)†
73.2 (54–87.6)‡
Kang
2010
Prospective
South Korea
1996–2006
197
42.2 (31.6–77.5)†
cohort
59 (34–80.8)‡
Kim
2019
Retrospective
cohort
South Korea
2000–2015
468
60.9 (29.9–107.0)
Bohbot
2018
Retrospective
cohort
Europe,
Multinational
2000–2015
439
60
Age is expressed as mean ± SD. Follow-up is reported as Median and IQR or mean ± SD. †Early aortic valve replacement group. ‡conservative management group. TABLE 2 | Characteristics of the included trials. TABLE 3 | Baseline characteristics of the patients of the included trials. End Points Characteristic
Early AVR group (n = 588)
Conservative strategy group (n = 661)
Kang 2020
Kang 2010
Kim 2019
Bohbot 2018
Kang 2020
Kang 2010
Kim 2019
Bohbot 2018
Age-y
65.0 ± 7.8
63 ± 11
61.0 ± 12.3
ND
63.4 ± 10.7
63 ± 11
67.1 ± 13.1
ND
Male gender-n (%)
37 (51)
55 (54)
110 (49.8)
ND
34 (47)
44 (46)
126 (51)
ND
Body surface area-m2
1.69 ± 0.17
1.65 ± 0.14
ND
ND
1.64 ± 0.17
1.62 ± 0.16
ND
ND
Body mass index
24.7 ± 3.4
23.9 ± 2.8
24.6 ± 3.2
ND
24.0 ± 2.6
24.1 ± 3.5
23.6 ± 3.2
ND
Diabetes-n (%)
13 (18)
10 (10)
37 (16.7)
ND
7 (10)
10 (11)
66 (26.7)
ND
Hypertension-n (%)
40 (55)
37 (36)
92 (41.6)
ND
39 (54)
39 (41)
122 (49.4)
ND
Smoking-n (%)
19 (26)
26 (25)
ND
ND
21 (29)
23 (24)
ND
ND
Hypercholesterolemia-n (%)
41 (56)
31 (30)
ND
ND
42 (58)
37 (39)
ND
ND
Coronary artery disease-n
5
ND
32
ND
1
ND
17
ND
Previous PCI-n (%)
3 (4)
ND
7 (3.2)
ND
1 (1)
ND
13 (5.3)
ND
Previous stroke-n (%)
3 (4)
ND
9 (4.1)
ND
3 (4)
ND
34 (13.8)
ND
Peripheral vascular disease-n (%)
1 (1)
ND
2 (0.9)
ND
2 (3)
ND
4 (1.6)
ND
Atrial fibrillation-n (%)
3 (4)
7 (7)
19 (8.6)
ND
6 (8)
8 (8)
34 (13.8)
ND
Serum creatinine level-mg/dl
0.84 ± 0.23
ND
0.9 ± 0.3
ND
0.83 ± 0.16
ND
1.1 ± 1.1
ND
EuroSCORE II score
0.9 ± 0.3‡
3.85 ± 1.66
ND
1.78 ± 0.92
0.9 ± 0.4‡
3.63 ± 1.92
ND
1.81 ± 0.93
Medication-n (%)
ACEI
4 (5)
8 (8)
ND
ND
0
4 (4)
ND
ND
ARB
24 (33)
14 (14)
ND
ND
28 (39)
9 (9)
ND
ND
Calcium antagonist
19 (26)
9 (9)
ND
ND
20 (28)
13 (14)
ND
ND
Beta-blocker
13 (18)
19 (19)
ND
ND
8 (11)
12 (13)
ND
ND
Diuretic
13 (18)
15 (15)
ND
ND
17 (24)
13 (14)
ND
ND
Statin
34 (47)
ND
ND
ND
32 (44)
ND
ND
ND
Peak aortic jet velocity-m/sec
5.14 ± 0.52
ND
4.7 ± 0.7
ND
5.04 ± 0.44
ND
4.5 ± 0.6
ND
Transaortic pressure gradient-mm Hg
Peak
106.9 ± 21.9
ND
ND
ND
102.5 ± 18.4
ND
ND
ND
Mean
64.3 ± 14.4
65 ± 13
55.0 ± 17.2
ND
62.7 ± 12.4
59 ± 12
48.6 ± 15.9
ND
Aortic valve area cm2
0 63 ± 0 09
0 61 ± 0 10
0 74 ± 0 21
ND
0 64 ± 0 09
0 62 ± 0 09
0 80 ± 0 19
ND TABLE 2 | Characteristics of the included trials. g
g
g
‡Scores on the European System for Cardiac Operative Risk Evaluation II (EuroSCORE II) are calculated by means of a logistic-regression equation and range from 0 to 100%.
ACEI, Angiotensin-converting–enzyme inhibitor; ARB, Angiotensin-receptor blocker. End Points y
We used odd ratios (ORs), hazard ratio (HR), and 95%
confidence intervals (95% CIs) to serve as primary index
statistics for dichotomous outcomes. OR, HR, and 95% CI
were calculated for each end point using a random effects
or fixed model effects according to I² value (if I² value of
<50%, we used fixed model effects). Subjects underwent early
AVR and conservative care were defined as AVR group and
conservative group, respectively. An OR/HR < 1 favors early
AVR and an OR/HR > 1 supports conservative management. Statistical heterogeneity was assessed by I2 statistic. I² value of
<50% indicated no obvious heterogeneity and I² value of more
than 50% indicated obvious heterogeneity. P values <0.05 were
considered statistically significant and all values were two-sided. The adjusted HR was extracted if available from observational
studies. If the HR was not described in a study, it was calculated
from a Kaplan–Meier curve. Survival data was extracted using the
Engauge Digitizer 10.8. Statistical analysis was performed using
the Review Manager 5.3 (Nordic Cochrane Center, The Cochrane
Collaboration, Copenhagen, Denmark) and survival analysis was
performed with the IBM SPSS Statistics 26. The primary end points were all-cause mortality and cardiac
mortality. Secondary end point was non-cardiac mortality. This FIGURE 2 | Funnel plot. FIGURE 2 | Funnel plot. FIGURE 2 | Funnel plot. FIGURE 3 | Study selection process. FIGURE 3 | Study selection process. FIGURE 3 | Study selection process. Frontiers in Cardiovascular Medicine | www.frontiersin.org Frontiers in Cardiovascular Medicine | www.frontiersin.org February 2021 | Volume 7 | Article 621149 3 Early Aortic Valve Replacement Yuan et al. TABLE 2 | Characteristics of the included trials. First author
Year
Study design
Region(s)
Study period
Number of
patients
Follow-up
(months)
Kang
2020
RCT
South Korea
2010–2015
145
74.4 (60–88.8)†
73.2 (54–87.6)‡
Kang
2010
Prospective
South Korea
1996–2006
197
42.2 (31.6–77.5)†
cohort
59 (34–80.8)‡
Kim
2019
Retrospective
cohort
South Korea
2000–2015
468
60.9 (29.9–107.0)
Bohbot
2018
Retrospective
cohort
Europe,
Multinational
2000–2015
439
60
Age is expressed as mean ± SD. Follow-up is reported as Median and IQR or mean ± SD. †Early aortic valve replacement group. ‡conservative management group. TABLE 3 | Baseline characteristics of the patients of the included trials. ht in kilograms divided by the square of the height in meters. ND, no data.
The body-mass index is the weight in kilograms divided by the square of the height in meters. End Points Characteristic
Early AVR group (n = 588)
Conservative strategy group (n = 661)
Kang 2020
Kang 2010
Kim 2019
Bohbot 2018
Kang 2020
Kang 2010
Kim 2019
Bohbot 2018
Age-y
65.0 ± 7.8
63 ± 11
61.0 ± 12.3
ND
63.4 ± 10.7
63 ± 11
67.1 ± 13.1
ND
Male gender-n (%)
37 (51)
55 (54)
110 (49.8)
ND
34 (47)
44 (46)
126 (51)
ND
Body surface area-m2
1.69 ± 0.17
1.65 ± 0.14
ND
ND
1.64 ± 0.17
1.62 ± 0.16
ND
ND
Body mass index
24.7 ± 3.4
23.9 ± 2.8
24.6 ± 3.2
ND
24.0 ± 2.6
24.1 ± 3.5
23.6 ± 3.2
ND
Diabetes-n (%)
13 (18)
10 (10)
37 (16.7)
ND
7 (10)
10 (11)
66 (26.7)
ND
Hypertension-n (%)
40 (55)
37 (36)
92 (41.6)
ND
39 (54)
39 (41)
122 (49.4)
ND
Smoking-n (%)
19 (26)
26 (25)
ND
ND
21 (29)
23 (24)
ND
ND
Hypercholesterolemia-n (%)
41 (56)
31 (30)
ND
ND
42 (58)
37 (39)
ND
ND
Coronary artery disease-n
5
ND
32
ND
1
ND
17
ND
Previous PCI-n (%)
3 (4)
ND
7 (3.2)
ND
1 (1)
ND
13 (5.3)
ND
Previous stroke-n (%)
3 (4)
ND
9 (4.1)
ND
3 (4)
ND
34 (13.8)
ND
Peripheral vascular disease-n (%)
1 (1)
ND
2 (0.9)
ND
2 (3)
ND
4 (1.6)
ND
Atrial fibrillation-n (%)
3 (4)
7 (7)
19 (8.6)
ND
6 (8)
8 (8)
34 (13.8)
ND
Serum creatinine level-mg/dl
0.84 ± 0.23
ND
0.9 ± 0.3
ND
0.83 ± 0.16
ND
1.1 ± 1.1
ND
EuroSCORE II score
0.9 ± 0.3‡
3.85 ± 1.66
ND
1.78 ± 0.92
0.9 ± 0.4‡
3.63 ± 1.92
ND
1.81 ± 0.93
Medication-n (%)
ACEI
4 (5)
8 (8)
ND
ND
0
4 (4)
ND
ND
ARB
24 (33)
14 (14)
ND
ND
28 (39)
9 (9)
ND
ND
Calcium antagonist
19 (26)
9 (9)
ND
ND
20 (28)
13 (14)
ND
ND
Beta-blocker
13 (18)
19 (19)
ND
ND
8 (11)
12 (13)
ND
ND
Diuretic
13 (18)
15 (15)
ND
ND
17 (24)
13 (14)
ND
ND
Statin
34 (47)
ND
ND
ND
32 (44)
ND
ND
ND
Peak aortic jet velocity-m/sec
5.14 ± 0.52
ND
4.7 ± 0.7
ND
5.04 ± 0.44
ND
4.5 ± 0.6
ND
Transaortic pressure gradient-mm Hg
Peak
106.9 ± 21.9
ND
ND
ND
102.5 ± 18.4
ND
ND
ND
Mean
64.3 ± 14.4
65 ± 13
55.0 ± 17.2
ND
62.7 ± 12.4
59 ± 12
48.6 ± 15.9
ND
Aortic valve area-cm2
0.63 ± 0.09
0.61 ± 0.10
0.74 ± 0.21
ND
0.64 ± 0.09
0.62 ± 0.09
0.80 ± 0.19
ND
Left ventricular mass index-g/m2
135.6 ± 38.2
158 ± 43
140.8 ± 54.4
ND
133.7 ± 31.1
159 ± 52
136.8 ± 40.3
ND
Left ventricular ejection fraction-%
64.8 ± 5.2
0.62 ± 0.07
63.7 ± 5.0
ND
64.8 ± 4.1
0.63 ± 0.07
63.1 ± 5.1
ND
Age is expressed as mean ± SD. The body-mass index is the weight in kilograms divided by the square of the height in meters. ata.
-mass index is the weight in kilograms divided by the square of the height in meters. End Points TABLE 3 | Baseline characteristics of the patients of the included trials. February 2021 | Volume 7 | Article 621149 Frontiers in Cardiovascular Medicine | www.frontiersin.org 4 Early Aortic Valve Replacement Yuan et al. Identification of Studies and Quality
Assessment and Baseline Characteristics
of Included Studies Our literature search yielded 2,478 studies. We acquired a total of
2,090 publications after the removal of duplicates. Fifteen articles
were included for eligibility evaluation after careful screening
of titles and abstracts. Eventually, four studies were included in
this meta-analysis. The flow chart of literature search was shown
in Figure 3. One eligible study was RCT, while the remaining
three studies were prospective or retrospective cohort studies
(Table 2). A total of 1,249 subjects with severe AS or very severe
AS were included. Patients with asymptomatic severe and severe
AS was assigned to the early AVR group (n = 588) or conservative
strategy group (n = 661). The baseline characteristics of the four
include articles were enclosed in Table 3. To assess the impact of
patient selection on the pooled effect estimate, we performed a
subgroup analysis, which exclusively included patients with very
severe AS. Cardiac Mortality Three studies (1, 17, 18) (810 patients: early AVR group =
396; conservative strategy group = 414) included data of
cardiac mortality. Compared to conservative care group, early
AVR was associated with significantly reduced cardiac mortality
(OR 0.12, 95% CI 0.02–0.62, P = 0.01, I² = 64%; HR 0.25,
95% CI 0.09–0.68, P = 0.007, I² = 66%) (Figures 5A,C). For patients with very severe asymptomatic AS, there was
also a significant reduction of cardiac mortality in early AVR
group (OR 0.04, 95% CI 0.01–0.21, P = 0.0001, I² = 0%)
(Figure 5B). RESULTS all-cause mortality. Early AVR was associated with significantly
lower mortality compared to conservative care (OR 0.16, 95%
CI 0.09–0.31, P < 0.00001, I² = 62%; HR 0.34, 95% CI 0.18–
0.64, P = 0.0008, I² = 62%) (Figures 4A,C). Two studies only
included very severe asymptomatic AS patients. There was also
a remarkable reduction in all-cause mortality among early AVR
subjects (OR 0.15, 95% CI 0.04–0.56, P = 0.005, I² = 63%)
(Figure 4B). All-Cause Mortality y
Three studies (1, 17, 18) (810 patients: early AVR group
= 396; conservative strategy group = 414) reported data of y
Four studies (1, 12, 17, 18) (1,249 patients: early AVR group Four studies (1, 12, 17, 18) (1,249 patients: early AVR group
= 588; conservative strategy group = 661) included data of = 588; conservative strategy group = 661) included data of FIGURE 4 | Assessment of the effect of early AVR on all-cause mortality. (A,C) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
all-cause mortality. (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on all-cause mortality. FIGURE 4 | Assessment of the effect of early AVR on all-cause mortality. (A,C) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
all-cause mortality. (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on all-cause mortality. FIGURE 4 | Assessment of the effect of early AVR on all-cause mortality. (A,C) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
all-cause mortality. (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on all-cause mortality. February 2021 | Volume 7 | Article 621149 Frontiers in Cardiovascular Medicine | www.frontiersin.org 5 Early Aortic Valve Replacement Yuan et al. FIGURE 5 | Assessment of the effect of early AVR on cardiac mortality. (A,C) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
cardiac mortality. (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on cardiac mortality. FIGURE 5 | Assessment of the effect of early AVR on cardiac mortality. (A,C) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
cardiac mortality. (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on cardiac mortality. FIGURE 5 | Assessment of the effect of early AVR on cardiac mortality. (A,C) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
cardiac mortality. Comment To the best of our knowledge, this is the first meta-analysis that
compares the outcomes of early AVR procedure and conservative
care approach in asymptomatic severe AS patients with preserved
LVEF. Our analysis consists of 1,249 asymptomatic severe AS
patients (LVEF ≥50%). In this meta-analysis, we conclude that
early surgery is associated with a lower risk of all-cause mortality,
cardiac mortality, and non-cardiac mortality. y
y
A key predicament is whether the risk of AVR outweighs
the risk of conservative treatment in patients of asymptomatic
severe AS. Previous meta-analysis confirms an overall mortality
reduction in AS patients after early AVR (19–21). These studies
included patients with reduced LVEF, and did not exclude
subjects who developed symptoms but deferred AVR procedure
(19). Thus, we conducted this meta-analysis and demonstrate
that asymptomatic severe AS patients with preserved LVEF could
also benefit from early surgery. For patients with very severe
asymptomatic AS, we draw the same conclusions considering its
potential in reducing all-cause mortality and cardiac mortality. However, there is no significant difference in non-cardiac
mortality. Moreover, we pooled the survival data from the
studies. The pooled data indicate that early AVR reduces
all-cause mortality in asymptomatic severe AS patients with
preserved LVEF. In summary, our meta-analysis suggests that early AVR
is
associated
with
reduced
all-cause
mortality,
cardiac
mortality, and non-cardiac mortality compared to conservative
management in asymptomatic severe AS patients with preserved
LVEF. More randomized controlled trials are currently underway
(26–30). Based on the current findings in our meta-analysis, we
tend to suggest clinicians to take an early interventional strategy
for asymptomatic AS patients with preserved LVEF. All-Cause Mortality FIGURE 7 | Survival assessment of the effect of early AVR on all-cause and cardiac mortality. (A) Survival analysis of all-cause mortality on subjects underwent early
AVR or conservative strategy. (B) Survival analysis of cardiac mortality on subjects underwent early AVR or conservative strategy. The risk stratification of patients with asymptomatic severe AS
is controversial. Valvuloarterial impedance and left ventricular
global longitudinal strain were deemed as sensitive markers to
identify early AVR candidates (LVEF ≥50%) (22). Serum B-
type natriuretic peptide (BNP) level, with a cut-offvalue of 100
pg/mL, was related to AS-related adverse events in asymptomatic
patients (LVEF ≥50%) (23). Patients with BNP <100 pg/mL
might benefit from watchful waiting strategy (23). However, the
natriuretic peptides stratification had not been adapted in current
clinical guidelines due to the lack of clinical evidence (24). In
patients with asymptomatic AS (LVEF ≥50%), hs-TnT >10 ng/L
was related with higher risk of events within 12 months (25). However, these findings were derived from observational studies
and need to be confirmed in RCTs. non-cardiac mortality. Compared to conservative care, early
AVR significantly declined the non-cardiac mortality (OR 0.36,
95% CI 0.21–0.63, P = 0.0003, I² = 13%) (Figure 6A). For
patients with very severe asymptomatic AS, early AVR yielded
no significant benefits over conservative care in non-cardiac
mortality (OR 0.46, 95% CI 0.18–1.16, P = 0.10, I² = 46%)
(Figure 6B). Survival Analysis The cumulative overall survival rate, calculated with life table
analysis, was 91% at 5 years in the early AVR group compared
with 68% in the conservative-care group (P < 0.001) (Figure 7A). The 5 year survival rates (survival free of cardiac death) were 96
and 80% in the early AVR group and conservative-care group,
respectively (P < 0.001) (Figure 7B). Our study had several limitations. First, the meta-analysis
consists of only four studies, including three non-randomized
trials that were subjected to possible selection bias. Moreover, two
articles were from the same group. Second, not every end-point
was reported in the four included studies. Third, there was not
enough data about operative mortality. Consequently, we could
not compare operative mortality. Fourth, we failed to include
asymptomatic patients who underwent transcatheter aortic valve
replacement (TAVR) due to limited data, which may be safer for
high risk surgery candidates. Finally, we failed to obtain original
survival data. Frontiers in Cardiovascular Medicine | www.frontiersin.org All-Cause Mortality (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on cardiac mortality. FIGURE 5 | Assessment of the effect of early AVR on cardiac mortality. (A,C) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
cardiac mortality. (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on cardiac mortality. FIGURE 6 | Assessment of the effect of early AVR on non-cardiac mortality. (A) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
non-cardiac mortality. (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on non-cardiac mortality. FIGURE 6 | Assessment of the effect of early AVR on non-cardiac mortality. (A) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
non-cardiac mortality. (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on non-cardiac mortality. FIGURE 6 | Assessment of the effect of early AVR on non-cardiac mortality. (A) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
non-cardiac mortality. (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on non-cardiac mortality. FIGURE 6 | Assessment of the effect of early AVR on non-cardiac mortality. (A) Forrest plot of studies assessing the effect of early AVR and conservative strategy on
non-cardiac mortality. (B) Forrest plot of studies assessing the effect of early AVR and conservative strategy in subjects with very severe AS on non-cardiac mortality. February 2021 | Volume 7 | Article 621149 Frontiers in Cardiovascular Medicine | www.frontiersin.org 6 Early Aortic Valve Replacement Yuan et al. FIGURE 7 | Survival assessment of the effect of early AVR on all-cause and cardiac mortality. (A) Survival analysis of all-cause mortality on subjects underwent early
AVR or conservative strategy. (B) Survival analysis of cardiac mortality on subjects underwent early AVR or conservative strategy. FIGURE 7 | Survival assessment of the effect of early AVR on all-cause and cardiac mortality. (A) Survival analysis of all-cause m
AVR or conservative strategy. (B) Survival analysis of cardiac mortality on subjects underwent early AVR or conservative strategy. REFERENCES Evaluation of patients with severe symptomatic aortic stenosis who
do not undergo aortic valve replacement: the potential role of subjectively
overestimated operative risk. Circ Cardiovasc Qual Outcomes. (2009) 2:533–
9. doi: 10.1161/CIRCOUTCOMES.109.848259 6. Bach DS, Siao D, Girard SE, Duvernoy C, McCallister BD Jr, Gualano SK,
et al. Evaluation of patients with severe symptomatic aortic stenosis who
do not undergo aortic valve replacement: the potential role of subjectively
overestimated operative risk. Circ Cardiovasc Qual Outcomes. (2009) 2:533–
9. doi: 10.1161/CIRCOUTCOMES.109.848259 18. Kang DH, Park SJ, Rim JH, Yun SC, Kim DH, Song JM, et al. Early
surgery
versus
conventional
treatment
in
asymptomatic
very
severe
aortic
stenosis. Circulation. (2010)
121:1502–
9. doi: 10.1161/CIRCULATIONAHA.109.909903 7. Nishimura RA, Otto CM, Bonow RO, Carabello BA, Erwin JP III, Guyton RA,
et al. 2014 AHA/ACC guideline for the management of patients with valvular
heart disease: a report of the American College of Cardiology/American Heart
Association task force on practice guidelines. J Thorac Cardiovasc Surg. (2014)
148: e1–132. doi: 10.1161/CIR.0000000000000029 19. Lim WY, Ramasamy A, Lloyd G, Bhattacharyya S. Meta-analysis of the
impact of intervention versus symptom-driven management in asymptomatic
severe aortic stenosis. Heart. (2017) 103:268–72. doi: 10.1136/heartjnl-2016-
309830 8. Nishimura RA, Otto CM, Bonow RO, Carabello BA, Erwin JP III, Fleisher
LA, et al. 2017 AHA/ACC focused update of the 2014 AHA/ACC guideline
for the management of patients with valvular heart disease: a report
of the American College of Cardiology/American Heart Association task
force on clinical practice guidelines. J Am Coll Cardiol. (2017) 70:252–
89. doi: 10.1016/j.jacc.2017.03.011 20. Sá MPBO, Cavalcanti LRP, Escorel Neto ACA, Perazzo AM, Simonato M,
Clavel MA, et al. Early aortic valve replacement versus watchful waiting in
asymptomatic severe aortic stenosis: a study-level meta-analysis. Struct Heart. (2019) 3:483–90. doi: 10.1080/24748706.2019.1652946 21. Genereux P, Stone G, O’Gara P, Guillaume GM, Bjorn R, Gennaro
G, et al. Early aortic valve replacement versus a conservative strategy
for asymptomatic severe aortic stenosis: meta-analysis of observational
studies. J Am Coll Cardiol. (2016) 67:2210. doi: 10.1016/S0735-1097(16)
32211-2 9. Campo J, Tsoris A, Kruse J, Karim A, Andrei AC, Liu MH, et al. Prognosis
of severe asymptomatic aortic stenosis with and without surgery. Ann Thorac
Surg. (2019) 108:74–9. doi: 10.1016/j.athoracsur.2019.01.031 g
j
10. Marechaux S, Hachicha Z, Bellouin A, Dumesnil JG, Meimoun P, Pasquet
A, et al. Usefulness of exercise-stress echocardiography for risk stratification
of true asymptomatic patients with aortic valve stenosis. Eur Heart J. (2010)
31:1390–7. DATA AVAILABILITY STATEMENT The original contributions presented in the study are included
in the article/Supplementary Material, further inquiries can be
directed to the corresponding author/s. February 2021 | Volume 7 | Article 621149 Frontiers in Cardiovascular Medicine | www.frontiersin.org Frontiers in Cardiovascular Medicine | www.frontiersin.org 7 Early Aortic Valve Replacement Yuan et al. FUNDING The Supplementary Material for this article can be found
online
at:
https://www.frontiersin.org/articles/10.3389/fcvm. 2020.621149/full#supplementary-material This
work
was
supported
by
funding
from
the
National
Natural
Science
Foundation
of
China AUTHOR CONTRIBUTIONS (No. 81970396
to
ZC
and
No. 81900416
to
YL),
and
the
Zhejiang
Provincial
Natural
Science
Foundation
for
Distinguished
Young
Scholars
(No. LR20H020002
to ZC). (No. 81970396
to
ZC
and
No. 81900416
to
YL),
and
the
Zhejiang
Provincial
Natural
Science
Foundation
for
Distinguished
Young
Scholars
(No. LR20H020002
to ZC). TY and YL collected data and performed analysis. TY and ZC
wrote the manuscript. YL, CB, and ZC made revision of the
manuscript. All authors contributed to the article and approved
the submitted version. REFERENCES asymptomatic severe aortic stenosis. J Am Coll Cardiol. (2015) 66:2827–
38. doi: 10.1016/j.jacc.2015.10.001 asymptomatic severe aortic stenosis. J Am Coll Cardiol. (2015) 66:2827–
38. doi: 10.1016/j.jacc.2015.10.001 1. Kang DH, Park SJ, Lee SA, Lee S, Kim DH, Kim HK, et al. Early surgery
or conservative care for asymptomatic aortic stenosis. N Engl J Med. (2020)
382:111–9. doi: 10.1056/NEJMoa1912846 1. Kang DH, Park SJ, Lee SA, Lee S, Kim DH, Kim HK, et al. Early surgery
or conservative care for asymptomatic aortic stenosis. N Engl J Med. (2020)
382:111–9. doi: 10.1056/NEJMoa1912846 14. Brown JM, O’Brien SM, Wu C, Sikora JA, Griffith BP, Gammie JS. Isolated
aortic valve replacement in North America comprising 108,687 patients
in 10 years: changes in risks, valve types, and outcomes in the Society
of Thoracic Surgeons National Database. J Thorac Cardiovasc Surg. (2009)
137:82–90. doi: 10.1016/j.jtcvs.2008.08.015 2. Généreux P, Stone GW, O’Gara PT, Marquis-Gravel G, Redfors B, Giustino
G, et al. Natural history, diagnostic approaches, and therapeutic strategies for
patients with asymptomatic severe aortic stenosis. J Am Coll Cardiol. (2016)
67:2263–88. doi: 10.1016/j.jacc.2016.02.057 j j
15. Otto CM, Burwash IG, Legget ME, Munt BI, Fujioka M, Healy NL,
et al. Prospective study of asymptomatic valvular aortic stenosis. Clinical,
echocardiographic, and exercise predictors of outcome. Circulation. (1997)
95:2262–70. doi: 10.1161/01.CIR.95.9.2262 3. Pineda AM, Kiefer TL. Asymptomatic severe aortic valve stenosis-when to
intervene: a review of the literature, current trials, and guidelines. Curr Cardiol
Rep. (2018) 20:129. doi: 10.1007/s11886-018-1072-x 16. Singh A, Greenwood JP, Berry C, Dawson DK, Hogrefe,K, Kelly DJ,
et al. Comparison of exercise testing and CMR measured myocardial
perfusion
reserve
for
predicting
outcome
in
asymptomatic
aortic
stenosis:
the
prognostic
importance
of
microvascular
dysfunction
in
aortic
stenosis
(PRIMID
AS)
study. Eur
Heart
J. (2017)
38:1222–9. doi: 10.1093/eurheartj/ehx001 4. Lindman BR, Clavel MA, Mathieu P, Lung B, Lancellotti P, Otto
CM,
et
al. Calcific
aortic
stenosis. Nat
Rev
Dis
Primers. (2016)
2:16006. doi: 10.1038/nrdp.2016.6 5. Lindman BR, Dweck MR, Lancellotti P, Généreux P, Piérard LA, O’Gara PT,
et al. Management of asymptomatic severe aortic stenosis. JACC Cardiovasc
Imaging. (2020) 13:481–93. doi: 10.1016/j.jcmg.2019.01.036 17. Kim
HJ,
Kim
JB,
Kim
HR,
Ju
MH,
Kang
DY,
Lee
SA,
et
al. Impact of valve replacement on long-term survival in asymptomatic
patients
with
severe
aortic
stenosis. Am
J
Cardiol. (2019)
123:1321–8. doi: 10.1016/j.amjcard.2019.01.035 6. Bach DS, Siao D, Girard SE, Duvernoy C, McCallister BD Jr, Gualano SK,
et al. REFERENCES doi: 10.1093/eurheartj/ehq076 22. Huded CP, Masri A, Kusunose K, Goodman AL, Grimm RA, Gillinov AM,
et al. Outcomes in asymptomatic severe aortic stenosis with preserved ejection
fraction undergoing rest and treadmill stress echocardiography. J Am Heart
Assoc. (2018) 7:e007880. doi: 10.1161/JAHA.117.007880 11. Pai RG, Kapoor N, Bansal RC, Varadarajan P. Malignant natural history
of asymptomatic severe aortic stenosis: benefit of aortic valve replacement. Ann
Thorac
Surg. (2006)
82:2116–22. doi:
10.1016/j.athoracsur.2006. 07.043 23. Nakatsuma K, Taniguchi T, Morimoto T, Shiomi H, Ando K, Kanamori N,
et al. B-type natriuretic peptide in patients with asymptomatic severe aortic
stenosis. Heart. (2019) 105:384–90. doi: 10.1136/heartjnl-2018-313746 12. Bohbot Y, Pasquet A, Rusinaru D, Delabre J, Delpierre Q, Altes A, et al. Asymptomatic severe aortic stenosis with preserved ejection fraction: early
surgery versus conservative management. J Am Coll Cardiol. (2018) 72:2938–
9. doi: 10.1016/j.jacc.2018.09.049 24. Martinez-Selles
M,
Bayes-Genis
A. Asymptomatic
severe
aortic
stenosis:
biomarkers
are
welcome. Heart. (2019)
105:355–
6. doi: 10.1136/heartjnl-2018-314122 25. Ferrer-Sistach E, Lupón J, Cediel G, Teis A, Gual F, Serrano S, et al. High-
sensitivity troponin T in asymptomatic severe aortic stenosis. Biomarkers. (2019) 24:334–40. doi: 10.1080/1354750X.2019.1567818 13. Taniguchi T, Morimoto T, Shiomi H, Ando K, Kanamori N, Murata
K, et al. Initial surgical versus conservative strategies in patients with February 2021 | Volume 7 | Article 621149 Frontiers in Cardiovascular Medicine | www.frontiersin.org 8 Yuan et al. Early Aortic Valve Replacement 30. NCT. Aortic
Valve
Replacement
Versus
Conservative
Treatment
In
Asymptomatic Severe Aortic Stenosis. Available online at: https://clinicaltrials. gov/show/NCT02436655 (accessed May 7, 2015). 26. NCT. Danish
National
Randomized
Study
on
Early
Aortic
Valve
Replacement in Patients with Asymptomatic Severe Aortic Stenosis. Available
online
at:
https://clinicaltrials.gov/show/NCT03972644
(accessed
June
3, 2019). Conflict of Interest: The authors declare that the research was conducted in the
absence of any commercial or financial relationships that could be construed as a
potential conflict of interest. 27. NCT. The Early Valve Replacement in Severe Asymptomatic Aortic Stenosis
Study. Available
online
at:
https://clinicaltrials.gov/show/NCT04204915
(accessed December 19, 2019). 28. NCT. Early Valve Replacement Guided by Biomarkers of LV Decompensation
in Asymptomatic Patients with Severe AS. Available online at: https://
clinicaltrials.gov/show/NCT03094143 (accessed March 29, 2017). Copyright © 2021 Yuan, Lu, Bian and Cai. This is an open-access article distributed
under the terms of the Creative Commons Attribution License (CC BY). Frontiers in Cardiovascular Medicine | www.frontiersin.org February 2021 | Volume 7 | Article 621149 REFERENCES The use,
distribution or reproduction in other forums is permitted, provided the original
author(s) and the copyright owner(s) are credited and that the original publication
in this journal is cited, in accordance with accepted academic practice. No use,
distribution or reproduction is permitted which does not comply with these terms. 29. NCT. Evaluation of Transcatheter Aortic Valve Replacement Compared
to Surveillance for Patients with Asymptomatic Severe Aortic Stenosis. Available online at https://clinicaltrials.gov/show/NCT03042104 (accessed
February 3, 2017). February 2021 | Volume 7 | Article 621149 Frontiers in Cardiovascular Medicine | www.frontiersin.org 9
|
https://openalex.org/W2188394296
|
https://hal-pasteur.archives-ouvertes.fr/pasteur-01383808/document
|
English
| null |
Metabolomic profiles delineate mycolactone signature in Buruli ulcer disease
|
Scientific reports
| 2,015
|
cc-by
| 8,074
|
To cite this version: Fatoumata Niang, Fred S. Sarfo, Michael Frimpong, Laure Guenin-Macé, Mark Wansbrough-Jones, et
al.. Metabolomic profiles delineate mycolactone signature in Buruli ulcer disease. Scientific Reports,
2015, 5, pp.17693 - 17693. 10.1038/srep17693. pasteur-01383808 Fatoumata Niang, Fred S. Sarfo, Michael Frimpong, Laure Guenin-Macé,
Mark Wansbrough-Jones, Timothy Stinear, Richard O. Phillips, Caroline
Demangel Fatoumata Niang, Fred S. Sarfo, Michael Frimpong, Laure Guenin-Macé,
Mark Wansbrough-Jones, Timothy Stinear, Richard O. Phillips, Caroline
Demangel Distributed under a Creative Commons Attribution 4.0 International License Metabolomic profiles delineate
mycolactone signature in Buruli
ulcer disease received: 21 July 2015
accepted: 02 November 2015
Published: 04 December 2015 received: 21 July 2015
accepted: 02 November 2015
Published: 04 December 2015 Fatoumata Niang1,2, Fred S. Sarfo3, Michael Frimpong4, Laure Guenin-Macé1,2,
Mark Wansbrough-Jones5, Timothy Stinear6, Richard O. Phillips3,7,* & Caroline Dem atoumata Niang1,2, Fred S. Sarfo3, Michael Frimpong4, Laure Guenin-Macé1,2,
5
6
3 7 * Fatoumata Niang1,2, Fred S. Sarfo3, Michael Frimpong4, Laure Guenin-Macé1,2,
Mark Wansbrough-Jones5, Timothy Stinear6, Richard O. Phillips3,7,* & Caroline Demangel1,2,* Infection of human skin with Mycobacterium ulcerans, the causative agent of Buruli ulcer, is
associated with the systemic diffusion of a bacterial macrolide named mycolactone. Patients with
progressive disease show alterations in their serum proteome, likely reflecting the inhibition of
secreted protein production by mycolactone at the cellular level. Here, we used semi-quantitative
metabolomics to characterize metabolic perturbations in serum samples of infected individuals, and
human cells exposed to mycolactone. Among the 430 metabolites profiled across 20 patients and 20
healthy endemic controls, there were significant differences in the serum levels of hexoses, steroid
hormones, acylcarnitines, purine, heme, bile acids, riboflavin and lysolipids. In parallel, analysis of
292 metabolites in human T cells treated or not with mycolactone showed alterations in hexoses,
lysolipids and purine catabolites. Together, these data demonstrate that M. ulcerans infection causes
systemic perturbations in the serum metabolome that can be ascribed to mycolactone. Of particular
importance to Buruli ulcer pathogenesis is that changes in blood sugar homeostasis in infected
patients are mirrored by alterations in hexose metabolism in mycolactone-exposed cells. Buruli ulcer (BU) is a necrotizing disease of the skin caused by infection with Mycobacterium ulcerans,
the third most prevalent mycobacterial pathogen in humans after M. tuberculosis and M. leprae1. How
M. ulcerans is transmitted to humans is not fully understood, however there is increasing evidence that
breaches in the skin barrier and exposure to contaminated environments are both required2–5. Since the
1980s, BU has spread in low-income developing countries of West Africa6. If not diagnosed or treated
appropriately, it can result in irreversible deformity, functional disability and life-threatening secondary
infections. The current diagnosis methods include acid-fast staining, culture or amplification of bacterial
DNA from fine needle aspirates, swabs or skin biopsies7. Treatment consists of the daily administration of
rifampicin and streptomycin for eight weeks8,9, and excision surgery of large lesions. Although effective,
control programs are costly, reactive rather than pro-active, and globally unsuited to field conditions. HAL Id: pasteur-01383808
https://pasteur.hal.science/pasteur-01383808v1
Submitted on 19 Oct 2016 L’archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d’enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés. HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers. Distributed under a Creative Commons Attribution 4.0 International License www.nature.com/scientificreports www.nature.com/scientificreports www.nature.com/scientificreports/ www.nature.com/scientificreports/ Cohort 1
Healthy controls (n = 20)
Patients with BU (n = 20)
Age, median (range), years
12 (6–35)
13 (7–35)
Sex, no. Male/no. Femelle
12/8
12/8
Ulcer category
I (lesion size ≤ 5 cm in widest diameter)
7
II (lesion size ≤ 15 cm in widest diameter)
13
Cohort 2
Healthy controls (n = 29)
Patients with BU (n = 38)
Age, median (range), years
13 (5–63)
13 (5–75)
Sex, no. Male/no. Femelle
14/15
18/20
Ulcer category
I (lesion size ≤ 5 cm in widest diameter)
16
II (lesion size ≤ 15 cm in widest diameter)
10
III (lesion size > 15 cm in widest diameter
or multiple lesions)
12 Table 1. Human cohort description. Table 1. Human cohort description. upon activation ex vivo15, suggesting that mycolactone modulates the functional biology of T cells at the
systemic level. In vitro, mycolactone altered the expression of homing receptors by resting T cells, and
the production of cytokines by activated T cells, without altering their viability17–19. Mycolactone was
shown to operate at the post-transcriptional level, and independently of mTOR17,20. Although its precise
mechanism of action remains to be elucidated, there is recent evidence that mycolactone blocks the
co-translational translocation of secreted and membrane-bound proteins into the endoplasmic reticu-
lum21,22. In line with this finding, the proteomic profiling of serum samples of patients with BU showed
significant reductions in the level of multiple soluble proteins, including T cell cytokines23. gi
p
p
g
y
To further explore the physiological consequences of bacterial production of mycolactone in infected
hosts, we compared the metabolic perturbations induced by infection with M. ulcerans in human hosts
to those induced by mycolactone treatment in human cells. Since bacterially-produced mycolactone
diffuses from cutaneous lesions into the peripheral circulation, we focused our analysis on serum sam-
ples. Jurkat T cells were selected as a model, because leukocytes are exposed to mycolactone during M. ulcerans infection15,16, and Jurkat T cells display the same functional defects as primary T cells upon
exposure to mycolactone in vitro17–19. In addition to provide novel insight into the molecular mecha-
nisms underlying BU pathogenesis, our study delineates mycolactone signature in the serum metabo-
lome of infected hosts. Metabolomic profiles delineate
mycolactone signature in Buruli
ulcer disease In
order to improve the detection and management of BU, it is essential to improve our understanding of
the molecular and cellular mechanisms underpinning BU pathogenesis10. p
g
p
g
M. ulcerans is unique amongst human pathogens in its capacity to produce a polyketide-derived
macrolide called mycolactone11–14. Bacterial production of mycolactone is essential for BU formation,
as shown by the avirulence of mycolactone-deficient strains of M. ulcerans in rodent models of infec-
tion. While bacteria grow primarily in host skin tissues, mycolactone gains access to the peripheral
circulation15,16. Foodpad infection of mice with wild-type, but not mycolactone-deficient strains of M. ulcerans, induced intrinsic defects in blood T cells evidenced by their incapacity to produce cytokines 1Institut Pasteur, Unité d’Immunobiologie de l’Infection, Paris, France. 2CNRS URA 1961, Paris, France. 3Komfo
Anokye Teaching Hospital, Kumasi, Ghana. 4Kumasi Centre for Collaborative Research, Kumasi, Ghana. 5St
George’s University of London, London, United Kingdom. 6University of Melbourne, Doherty Institute for Infection
and Immunity, Melbourne, Australia. 7Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. *These authors jointly supervised this work.- Correspondence and requests for materials should be addressed to
C.D. (email: caroline.demangel@pasteur.fr) Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 1 Methods
hi Blood samples (8 ml) were collected in
the field in BD Vacutainer Serum separator tubes, mixed and left to clot according to the manufacturer’s
recommendations. Tubes were then transported within 2 h on ice to the laboratory, for centrifugation and
serum separation. The recovered serum (3–4 ml) was aliquoted in Eppendorf SafelockTM tubes and stored
at − 80oC. Samples of cohort 1 individuals were shipped to Institut Pasteur (Paris, France) on dry ice,
thawed and re-aliquoted in 100 μ l-containing Eppendorf Safelock tubes prior to shipping to Metabolon
Inc. on dry ice. Serum samples of cohort 2 individuals were shipped to St George’s University of London
on dry ice, and assayed for cortisol using Siemens Advia Centaur Competitive Immunoassay and Direct
Chemiluminescent Technology. Mycolactone. Mycolactone A/B was purified from M. ulcerans bacterial cell pellets (strain 1615, ATCC
35840) as previously described11. Mycolactone was quantified by measure of absorbance (λ max = 362 nm;
log ε = 4.29)26, and purity controlled by mass spectrometry. A stock solution (20 μ M) was prepared in
ethanol solvent that was diluted 1000X for T cell treatments. Controls exposed to the same volume of
vehicle were included. Cellular studies. Jurkat E6.1 (ATCC TIB-152TM) T cells were cultured in RPMI GlutamaxTM (Life
Technologies), supplemented with 10% heat-inactivated fetal calf serum (FCS) (Invitrogen) and peni-
cillin/streptomycin (100 U/ml, 100 μ g/ml). Cells in exponential phase of growth were exposed to 20 nM
mycolactone (n = 6) or ethanol (n = 5) for 16 h. Cells were recovered and dried by two rounds of cen-
trifugation at 750 g for 3 min, flash-frozen, and stored at − 80 °C until analysis. Metabolomic profiling. Semi-quantitative metabolomic analyses were performed by Metabolon
Inc., as described (http://www.metabolon.com/). On the day of extraction, serum samples (100 μ l) or
cell pellets (50 μ l) were thawed on ice. Proteins were precipitated with methanol, using an automated
liquid handler (Hamilton LabStar). The methanol contained four standards, which permitted the mon-
itoring of extraction efficiency. The resulting extract was divided into three fractions that were placed
briefly on a TurboVap® (Zymark) to remove the organic solvent, frozen and dried under vacuum. Samples destined to LC/MS analysis were reconstituted in acidic or basic LC-compatible solvents,
each of which contained 11 or more injection standards at fixed concentrations. Methods
hi Ethics statement. The ethics committee at the School of Medical Sciences, Kwame Nkrumah University
of Science and Technology, Kumasi, Ghana approved the protocol of this study (CHRPE/11/28/06). All
adult subjects provided written informed consent, and a parent or guardian of any child participant
provided informed consent on their behalf. The review board also gave approval to document informed
consent by use of thumbprints for illiterate participants. Studies using human subjects were performed
in accordance with the approved guidelines and regulations. Human studies. Two cohorts of patients and age- and gender-matched healthy controls were recruited
for the purposes of this study (Table 1). The first cohort was used to compare the metabolic profiles of BU
patients and controls from the same community. The second cohort was recruited subsequently, in order
to confirm altered cortisol levels in BU patients, and detect an eventual association with lesion severity. Patients were from the middle forest belt of Ashanti Region of Ghana, from Buruli ulcer endemic villages
near Tepa Government Hospital (Ahafo Ano North District), Agogo Presbyterian Hospital and Nkawie
Government Hospital (Atwima Nwabiagya district). They were included in the study if they met the
WHO clinical case definition of M. ulcerans disease; were not pregnant; were not receiving antibiotic
treatment; had no history of tuberculosis, leprosy, or liver, kidney, or hearing impairment. On the day
of clinical diagnosis, fine needle aspirates were taken for PCR amplification of IS2404 repeat sequence
of M. ulcerans24. Punch biopsy specimens of 4 mm diameter were also stained for acid-fast bacilli and
cultured on Lowenstein-Jensen slopes, as previously described25. Patients were started on streptomycin
15 mg/kg and rifampicin 10 mg/kg treatment daily for 8 weeks, as recommended by the WHO, at village
health posts under direct observation. Blood samples were also collected at the day of clinical diagnosis
of BU, before the initiation of antibiotic therapy. Patients were on empty stomach, in an overnight-fasted
state. They were asked if they had taken antibiotic or other medication. Only those who had responded
negatively and had confirmed BU were subsequently included in the study. Healthy individuals from the
same endemic areas also provided serum samples to serve as a comparator. Serum sampling, freezing Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 2 www.nature.com/scientificreports/ and storage were performed in a standardized manner, as follows. Methods
hi One aliquot was ana-
lyzed using acidic positive ion optimized conditions and the other using basic negative ion optimized
conditions in two independent injections using separate dedicated columns. Extracts reconstituted in
acidic conditions were gradient eluted using water and methanol both containing 0.1% formic acid,
while the basic extracts, which also used water/methanol, contained 6.5 mM ammonium bicarbonate. The samples destined for GC/MS analysis were re-dried under vacuum desiccation for a minimum
of 24 h prior to being derivatized under dried nitrogen using bistrimethyl-silyl-triflouroacetamide. Technical replicates created from a homogenous pool containing a small amount of all study samples
were included. The UPLC-MS/MS platform used a Waters Acquity UPLC with Waters UPLC BEH C18
columns (2.1 × 100 mm, 1.7 μ m) and a ThermoFisher LTQ mass spectrometer. GC-MS was performed
on a Thermo-Finnigan Trace DSQ fast-scanning single-quadrupole MS. Metabolites were identified
by automated comparison of the ion features in the experimental samples to a reference library of
chemical standard entries that included retention time, molecular weight (m/z), preferred adducts,
and in-source fragments as well as associated MS spectra. Peaks were quantified by area under the
curve measurements. Raw area counts for each metabolite in each sample were normalized to correct
for variation resulting from instrument inter-day, tuning differences by the median value for each
run-day, therefore setting the medians to 1.0 for each run. Metabolites missing more than one value
were excluded from the analysis. Statistical analyses. Following log transformation and normalization, Principal Component Analysis
(PCA) was used to identify the biochemicals discriminating patients from controls with a false discovery
rate (q-value) inferior to 0.2. We then used Welch’s two-sample t-test to identify biochemicals differing
significantly between the two groups (p ≤ 0.05). The metabolomic analysis of Jurkat T cells being part
of a larger study including multiple treatments, two-way ANOVA with contrasts was used to identify
biochemicals differing significantly between mycolactone- and vehicle-treated groups. In both human
and cell studies, q-values were calculated for each metabolite to take into account multiple comparisons. The GraphPad Prism software (v5.0d, La Jolla, CA) was used for box-and-whisker plot representation,
with outliers identified by Tukey’s test. Results and Discussioni Metabolomic profiling of BU. Serum samples were harvested from 20 patients with newly diag-
nosed BU lesions and 20 age- and gender-matched healthy controls from the same endemic community
(Cohort 1, Table 1). Following solvent extraction, samples were split for analysis on liquid or gas chro-
matography platforms coupled with mass spectrometry. A total of 430 metabolites were identified, whose
spectrometric signals were normalized and compared across patients and controls. PCA revealed a sepa-
rate clustering between the patient and control populations (Fig. 1), showing that BU disease is associated
with significant metabolic alterations. Nineteen (4%) metabolites were discriminative (p-value < 0.01, Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 3 www.nature.com/scientificreports/ www.nature.com/scientificreports/ re.com/scientificreports/
Figure 1. Metabolic signature of BU. PCA scatterplot of serum metabolites in patients with BU and
controls. The most discriminating biochemicals (q-value ≤ 0.2) are shown, with their p-value and variati
coefficient (Fold change) across groups (Blue: relatively increased; Yellow: relatively decreased in patient
versus controls). Figure 1. Metabolic signature of BU. PCA scatterplot of serum metabolites in patients with BU and
controls. The most discriminating biochemicals (q-value ≤ 0.2) are shown, with their p-value and variation
coefficient (Fold change) across groups (Blue: relatively increased; Yellow: relatively decreased in patients
versus controls). Figure 1. Metabolic signature of BU. PCA scatterplot of serum metabolites in patients with BU and
controls. The most discriminating biochemicals (q-value ≤ 0.2) are shown, with their p-value and variation
coefficient (Fold change) across groups (Blue: relatively increased; Yellow: relatively decreased in patients
versus controls). Figure 1. Metabolic signature of BU. PCA scatterplot of serum metabolites in patients with BU and
controls. The most discriminating biochemicals (q-value ≤ 0.2) are shown, with their p-value and variation
coefficient (Fold change) across groups (Blue: relatively increased; Yellow: relatively decreased in patients
versus controls). q-value < 0.2). Among them, 11 were upregulated in patients relative to controls, whereas 8 were down-
regulated. Intermediates of glycolysis, pentose-phosphate pathway (PPP) and tricarboxylic acid cycle
(TCA) were modulated, indicating that energy-generating pathways had been perturbed. Alterations in
the peptide, lipid and nucleotide metabolic pathways were also observed. We used a Welch’s two-sample
t-test (p < 0.05) to gain further insight into metabolite differences between groups. Fifty-four metabolites
(12%) were present at significantly different levels in patients with BU, compared to controls (Table 2). Results and Discussioni They clustered into the hexose, fatty acid, lysolipid, steroid hormones, purine and heme metabolism,
leading us to examine these pathways in greater detail. Hexoses. Compared to controls, patients with BU displayed elevated levels of all detected hexoses
(glucose, fructose and mannose) (Fig. 2a). These sugars enter the cells via common membrane trans-
porters of the solute carrier (SLC)-2 family. The 15–50% increase in serum hexoses may thus indicate
defective uptake by SLC2 transporters, or increased hepatic gluconeogenesis. The PPP requires glucose
for the generation of pentoses (Fig. 2a). We observed a relative accumulation of xylulose in patient serum
(Table 2). Since serum levels of the xylulose precursor xylitol were unchanged, it suggested that genera-
tion of PPP intermediate xylulose-5-phosphate might be reduced. Finally, the TCA cycle intermediates
citrate and malate were decreased in patients with BU, while alpha-ketoglutarate, succinate and fumarate
were unchanged (Supplementary Figure S2 and Table 2). The TCA cycle is essential for the generation
of ATP and precursors for various biosynthetic pathways. It requires equilibrated anaplerosis and cata-
plerosis (for entry and exit of TCA anions, respectively)27. In patients with BU, the imbalance between
anaplerosis substrates (alpha-ketoglutarate) and cataplerosis substrates (citrate and malate) suggests that
TCA cycle function may be impaired. Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 4 www.nature.com/scientificreports/ www.nature.com/scientificreports/ Metabolism
Biochemical Pathway
Metabolite
Fold change
(Patient vs Ctrl)
p-value
q-value
Amino acid
Histidine
histidine
0,85
0,002
0,090
Lysine
N6-acetyllysine
0,80
0,010
0,172
Phenylalanine and Tyrosine
p-cresol sulfate
0,64
0,006
0,146
Cysteine and Methionine
S-methylcysteine
0,67
0,049
0,388
Glutathione
5-oxoproline
0,84
0,002
0,090
Peptide
Dipeptide
glycylvaline
2,03
0,000
0,023
isoleucylglycine
1,21
0,038
0,334
phenylalanylleucine
1,60
0,008
0,169
Gamma-glutamyl amino acid
gamma-glutamylisoleucine
0,77
0,046
0,386
gamma-glutamylmethionine
0,81
0,025
0,295
Fibrinogen cleavage peptide
ADSGEGDFXAEGGGVR
1,47
0,029
0,316
DSGEGDFXAEGGGVR
1,63
0,002
0,090
Carbohydrate
Hexose
fructose
1,50
0,031
0,316
mannose
1,51
0,000
0,023
Glycolysis and Gluconeogenesis
glucose
1,15
0,001
0,090
Nucleotide Sugar and Pentose
xylulose
1,40
0,003
0,119
Energy
TCA cycle
citrate
0,84
0,012
0,184
malate
0,67
0,001
0,090
Lipid
Monohydroxy fatty acid
4-hydroxybutyrate (GHB)
0,72
0,048
0,388
2-hydroxyoctanoate
0,74
0,028
0,316
3-hydroxyoctanoate
0,74
0,011
0,181
2-hydroxystearate
1,18
0,011
0,181
2-hydroxypalmitate
1,21
0,006
0,146
Beta-oxidation
palmitoylcarnitine
0,66
0,012
0,181
oleoylcarnitine
0,63
0,008
0,169
Bile acid
glycodeoxycholate
0,58
0,010
0,172
glycolithocholate sulfate
0,33
0,000
0,023
taurolithocholate 3-sulfate
0,42
0,006
0,146
Glycerolipid
choline
0,91
0,035
0,334
Lysolipid
1-oleoylglycerophosphoethanolamine
0,71
0,009
0,169
2-oleoylglycerophosphoethanolamine
0,74
0,032
0,316
1-linoleoylglycerophosphoethanolamine
0,73
0,028
0,316
1-palmitoylglycerophosphocholine
0,88
0,042
0,367
2-palmitoylglycerophosphocholine
0,73
0,024
0,284
1-oleoylglycerophosphocholine
0,83
0,038
0,334
1-linoleoylglycerophosphocholine
0,74
0,005
0,146
2-linoleoylglycerophosphocholine
0,70
0,005
0,146
1-dihomo-linoleoylglycerophosphocholine
0,73
0,009
0,169
Monoacylglycerol
1-stearoylglycerol (1-monostearin)
1,25
0,038
0,334
Sphingolipid
sphinganine
0,55
0,001
0,090
Sterol/Steroid
cholesterol
1,13
0,020
0,243
cortisol
1,42
0,018
0,237
cortisone
1,26
0,007
0,157
Nucleotide
Purine
xanthine
1,27
0,004
0,146
inosine
2,01
0,004
0,146
Cofactor
Heme
bilirubin (Z,Z)
0,44
0,037
0,334
bilirubin (E,E)
0,28
0,014
0,204
biliverdin
0,66
0,019
0,243
Continued Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 5 www.nature.com/scientificreports/ Metabolism
Biochemical Pathway
Metabolite
Fold change
(Patient vs Ctrl)
p-value
q-value
Vitamin
Riboflavin
riboflavin (Vitamin B2)
1,82
0,048
0,388
Tocopherol
gamma-CEHC
0,67
0,017
0,236
Xenobiotic
Chemical
4-methylcatechol sulfate
0,74
0,016
0,221
hexaethylene glycol
1,20
0,030
0,316
octaethylene glycol
1,15
0,031
0,316
pentaethylene glycol
1,13
0,049
0,388
Table 2. Metabolic signature of BU in human patients. Table 2. Metabolic signature of BU in human patients. To determine if some of these effects could result from the action of mycolactone, we profiled the
metabolome of Jurkat T cells exposed for 16 h to 20 nM of the purified factor, or vehicle as control. In accordance with previous studies19, this treatment decreased the production of membrane recep-
tor CD62L without altering the cell viability (Supplementary Figure S1). www.nature.com/scientificreports/ Total cell metabolites were
extracted and analyzed similar to serum samples, leading to the identification and relative quantifica-
tion of 292 metabolites. Among them, 59 differed significantly between experimental groups (Table 3). Notably, glucose, galactose and mannose were relatively less concentrated in mycolactone-exposed T
cells (Fig. 2b), arguing for a defect in cellular uptake by membrane transporters. Intracellular levels
of glucose-1-phosphate and mannose-6-phosphate were downregulated in mycolactone-treated T cells
(Table 3), indicative of altered glycolysis. Mycolactone also triggered the intracellular accumulation of
acetylcarnitine, propionylcarnitine and butyrylcarnitine (Table 3). On the contrary, serum levels of pal-
mitoylcarnitine and oleoylcarnitine were decreased in patients with BU (Table 2). Because they facilitate
the transport of fatty acids across mitochondrial membranes, a rate-limiting step in fatty acid oxida-
tion (FAO), circulating acylcarnitines are clinically-used biomarkers of FAO disorders28. At the cellular
level, the accumulation of acylcarnitines correlates with reduced oxidation of glucose and insulin resist-
ance29. The increased levels of serum hexoses in patients with BU may thus be due, at least partially, to
mycolactone-induced defects in hexose uptake and FAO. With the exception of mannose, none of the
above-described alterations were observed in patients with TB30. Steroid hormones. Glucocorticoids assist in the regulation of glucose homeostasis through the stim-
ulation of hepatic gluconeogenesis and downregulation of glucose transport systems. There was a rela-
tive augmentation in serum cholesterol and downstream glucocorticoid hormones cortisol in patients
with BU (Fig. 3a). Cortisone, a conversion product of cortisol with weaker glucocorticoid activity, was
also increased whereas other steroidal hormones were not significantly impacted. To validate these
findings with an independent and quantitative approach, an additional cohort of patients and controls
was assayed for serum cortisol (Cohort 2, Table 1). In agreement with our metabolomics data, the
mean cortisol level was higher in patients with BU, compared to controls (Fig. 3b). Although variable,
cortisol levels trended higher in patients with more severe lesions (Fig. 3b). No relationship could be
demonstrated between serum cortisol and paradoxical reaction, or the clinical form of lesions (nodule,
plaque, oedema or ulcer). Together with the data in Fig. 2, these observations suggest that glucocorti-
coid hormones may be induced in patients with progressive ulcers, in order to raise blood sugars. Since
corticosteroids inhibit wound healing, increased circulation in patients may delay their clinical response
to antibiotic treatment. Purine catabolites. www.nature.com/scientificreports/ Patients with BU displayed elevated serum levels of the purine catabolites ino-
sine and xanthine (Supplementary Figure S3a and Table 2). These metabolites were not augmented in
patients with active TB30, suggesting that they do not reflect a general response to mycobacterial infec-
tion. Interestingly, opposite variations were observed in T cells exposed to mycolactone (Supplementary
Figure S3b and Table 2), whereas adenine and guanine, and the pyrimidine catabolite uracil remained
unchanged. Although the underlying molecular mechanism is unclear, increased serum inosine and xan-
thine may thus constitute specific traits of BU. Gamma-glutamyl amino acids. Among the metabolites discriminating patients from controls was
the gamma-glutamyl amino acid degradation product 5-oxoproline (Fig. 1), which serum level was rela-
tively lower in patients. Interestingly, patients also displayed reduced levels of gamma-glutamylisoleucine
and gamma-glutamylmethionine (Table 2). Gamma-glutamyl amino acids result from the transfer of the
gamma-glutamyl moiety of glutathione to acceptor amino acids by the liver enzyme gamma-glutamyl
transferase (GGT). We reported previously that BU patients display normal serum GGT23. Since iso-
leucine and methionine were unchanged in patients versus controls in the present study, we can specu-
late that downregulation of their gamma-glutamyl derivatives is due to limited glutathione availability. Extracellular glutathione results from synthesis, consumption and extrusion by producing cells31. Binding Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 6 ntificreports/
Figure 2. Increased serum hexoses in BU patients mirror decreased hexose concentrations in
mycolactone-exposed cells. (a) Differential serum levels of the detected hexoses in BU patients versus
controls, shown as box and whiskers and in the context of energy-generating metabolic pathways. Biochemicals in bold red were relatively increased in patients versus controls. Those in bold black were
detected at comparable levels. Those in grey were not detected. (b) Differential concentrations of detected
hexoses in mycolactone- and vehicle-treated Jurkat T cells, shown as box and whiskers. *p < 0.05,
***p < 0.001. www.nature.com/scientificreports/ igure 2. Increased serum hexoses in BU patients mirror decreased hexose concentrations in f Figure 2. Increased serum hexoses in BU patients mirror decreased hexose concentrations in
mycolactone-exposed cells. (a) Differential serum levels of the detected hexoses in BU patients versus
controls, shown as box and whiskers and in the context of energy-generating metabolic pathways. Biochemicals in bold red were relatively increased in patients versus controls. Those in bold black were
detected at comparable levels. Those in grey were not detected. www.nature.com/scientificreports/ (b) Differential concentrations of detected
hexoses in mycolactone- and vehicle-treated Jurkat T cells, shown as box and whiskers. *p < 0.05,
***p < 0.001. of glutamate to cysteine is the first and rate-limiting step in the biosynthesis of this tripeptide. In Jurkat
cells, mycolactone had mixed effects on the intracellular levels of gamma-glutamyl amino acids. It did
not alter significantly the intracellular levels of cysteine, glutamate nor glutathione (reduced and oxi-
dized forms). Although extracellular glutathione measurements would be required to confirm it, these
data suggest that BU-associated alterations in serum gamma-glutamyl amino acids, and potentially glu-
tathione and redox homeostasis, are independent of mycolactone. Bile acids. Bile acids are synthesized from cholesterol by 7-alpha-hydroxylase (CYP7A1) in the liver
(Fig. 4). Bile acids facilitate cholesterol elimination, intestinal absorption and excretion of lipids and
lipid-soluble molecules. They are also important signaling molecules regulating energy homeostasis,
inflammation and liver regeneration32. Compared to controls, patients with BU displayed significantly
higher levels of cholesterol (Fig. 2a) and normal levels of 7-alpha-hydroxycholesterol and cholate, sug-
gesting that precursors of bile acid synthesis are not limiting. www.nature.com/scientificreports/ *p < 0.05, **p < 0.01. sulfate and taurolithocholate 3 sulfate were significantly downregulated in patients with BU (Fig 4) No www.nature.com/scientificreports/ Metabolism
Biochemical Pathway
Metabolite
Fold change
(Myco vs Ctrl)
p-value
q-value
Lysolipid
1-myristoylglycerophosphocholine
0,60
0,033
0,100
1-pentadecanoylglycerophosphocholine
0,64
0,038
0,109
Neurotransmitter
acetylcholine
9,40
0,000
0,000
Sterol/Steroid
lathosterol
1,66
0,025
0,089
Nucleotide
Purine
xanthine
0,72
0,002
0,024
hypoxanthine
0,66
0,020
0,084
inosine
0,60
0,015
0,070
inosine 5’-monophosphate (IMP)
0,68
0,042
0,114
N1-methyladenosine
0,70
0,033
0,100
Cofactor and Vitamin
Biotin
biotin
1,94
0,000
0,000
Pantothenate and CoA
pantothenate
1,51
0,000
0,004
T bl 3
M t b li
i
t
f
l
t
i
h
T
ll Metabolism
Biochemical Pathway
Metabolite
Fold change
(Myco vs Ctrl)
p-value
q-value
Lysolipid
1-myristoylglycerophosphocholine
0,60
0,033
0,100
1-pentadecanoylglycerophosphocholine
0,64
0,038
0,109
Neurotransmitter
acetylcholine
9,40
0,000
0,000
Sterol/Steroid
lathosterol
1,66
0,025
0,089
Nucleotide
Purine
xanthine
0,72
0,002
0,024
hypoxanthine
0,66
0,020
0,084
inosine
0,60
0,015
0,070
inosine 5’-monophosphate (IMP)
0,68
0,042
0,114
N1-methyladenosine
0,70
0,033
0,100
Cofactor and Vitamin
Biotin
biotin
1,94
0,000
0,000
Pantothenate and CoA
pantothenate
1,51
0,000
0,004
Table 3. Metabolic signature of mycolactone in human T cells. Metabolism
Biochemical Pathway
Metabolite
Fold change
(Myco vs Ctrl)
p-value
q-value
Lysolipid
1-myristoylglycerophosphocholine
0,60
0,033
0,100
1-pentadecanoylglycerophosphocholine
0,64
0,038
0,109
Neurotransmitter
acetylcholine
9,40
0,000
0,000
Sterol/Steroid
lathosterol
1,66
0,025
0,089
Nucleotide
Purine
xanthine
0,72
0,002
0,024
hypoxanthine
0,66
0,020
0,084
inosine
0,60
0,015
0,070
inosine 5’-monophosphate (IMP)
0,68
0,042
0,114
N1-methyladenosine
0,70
0,033
0,100
Cofactor and Vitamin
Biotin
biotin
1,94
0,000
0,000
Pantothenate and CoA
pantothenate
1,51
0,000
0,004
Table 3. Metabolic signature of mycolactone in human T cells. Table 3. Metabolic signature of mycolactone in human T cells. Figure 3. Increased serum glucocorticoids in BU patients. (a) Differential serum levels of glucocorticoid
hormones and cholesterol in BU patients and controls. (b) Absolute concentrations of serum cortisol in BU
patients versus controls (left), and patients with different ulcer category (right). Data are presented as box
and whiskers. *p < 0.05, **p < 0.01. Figure 3. Increased serum glucocorticoids in BU patients. (a) Differential serum levels of glucocorticoid
hormones and cholesterol in BU patients and controls. (b) Absolute concentrations of serum cortisol in BU
patients versus controls (left), and patients with different ulcer category (right). Data are presented as box
and whiskers. *p < 0.05, **p < 0.01. Figure 3. Increased serum glucocorticoids in BU patients. www.nature.com/scientificreports/ Yet glycodeoxycholate, glycolithocholate Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 7 www.nature.com/scientificreports/ www.nature.com/scientificreports/
Metabolism
Biochemical Pathway
Metabolite
Fold change
(Myco vs Ctrl)
p-value
q-value
Amino acid
Glycine, Serine and Threonine
betaine
1,38
0,003
0,028
beta-alanine
1,41
0,038
0,109
Glutamate
glutamate
0,77
0,011
0,065
pyroglutamine
1,31
0,023
0,089
gamma-aminobutyrate (GABA)
1,43
0,014
0,066
Histidine
histidine
0,78
0,017
0,072
Lysine
lysine
0,46
0,008
0,053
2-aminoadipate
0,53
0,000
0,005
Phenylalanine and Tyrosine
phenylalanine
0,79
0,026
0,089
tyrosine
0,71
0,002
0,024
Tryptophan
tryptophan
0,77
0,025
0,089
Valine, Leucine and Isoleucine
leucine
0,80
0,031
0,100
valine
0,81
0,049
0,128
Cysteine and Methionine
taurine
1,34
0,027
0,089
methionine
0,76
0,023
0,089
2-hydroxybutyrate (AHB)
1,25
0,047
0,124
Urea cycle, Arginine and Proline
dimethylarginine (SDMA + ADMA)
0,65
0,010
0,063
N-acetylornithine
0,79
0,024
0,089
argininosuccinate
0,43
0,009
0,056
Creatine
creatine
1,44
0,001
0,018
Polyamine
putrescine
1,84
0,001
0,015
Peptide
Dipeptide
glycylproline
0,68
0,036
0,106
glycylleucine
0,69
0,039
0,109
glycylthreonine
0,70
0,003
0,031
prolylglycine
0,58
0,004
0,034
prolylalanine
0,56
0,004
0,034
prolylglutamine
0,58
0,005
0,039
cysteinylglycine
0,58
0,031
0,100
prolylglutamate
0,62
0,013
0,065
phenylalanylaspartate
0,61
0,008
0,053
Gamma-glutamyl amino acid
gamma-glutamylvaline
1,77
0,000
0,004
gamma-glutamylleucine
1,58
0,001
0,018
gamma-glutamylisoleucine
1,40
0,012
0,065
gamma-glutamylmethionine
0,57
0,006
0,047
gamma-glutamylglutamine
0,62
0,000
0,007
gamma-glutamylthreonine
2,10
0,000
0,000
Carbohydrate
Aminosugar
Isobar: UDP-acetylglucosamine, UDP-acetylgalactosamine
1,45
0,017
0,072
Hexose
galactose
0,54
0,012
0,065
6′ -sialyllactose
2,30
0,000
0,005
mannose
0,39
0,014
0,066
mannose-6-phosphate
0,53
0,012
0,065
sorbitol
1,30
0,042
0,114
Glycolysis
glucose 1-phosphate
0,58
0,033
0,100
glucose
0,46
0,023
0,089
Lipid
Beta-oxidation
propionylcarnitine
1,80
0,001
0,018
butyrylcarnitine
2,84
0,002
0,021
Carnitine
acetylcarnitine
1,34
0,013
0,065
Glycerolipid
choline phosphate
1,27
0,026
0,089
Continued 8 www.nature.com/scientificreports/
Metabolism
Biochemical Pathway
Metabolite
Fold change
(Myco vs Ctrl)
p-value
q-value
Lysolipid
1-myristoylglycerophosphocholine
0,60
0,033
0,100
1-pentadecanoylglycerophosphocholine
0,64
0,038
0,109
Neurotransmitter
acetylcholine
9,40
0,000
0,000
Sterol/Steroid
lathosterol
1,66
0,025
0,089
Nucleotide
Purine
xanthine
0,72
0,002
0,024
hypoxanthine
0,66
0,020
0,084
inosine
0,60
0,015
0,070
inosine 5’-monophosphate (IMP)
0,68
0,042
0,114
N1-methyladenosine
0,70
0,033
0,100
Cofactor and Vitamin
Biotin
biotin
1,94
0,000
0,000
Pantothenate and CoA
pantothenate
1,51
0,000
0,004
Table 3. Metabolic signature of mycolactone in human T cells. Figure 3. Increased serum glucocorticoids in BU patients. (a) Differential serum levels of glucocorticoid
hormones and cholesterol in BU patients and controls. (b) Absolute concentrations of serum cortisol in BU
patients versus controls (left), and patients with different ulcer category (right). Data are presented as box
and whiskers. www.nature.com/scientificreports/ (a) Differential serum levels of glucocorticoid
hormones and cholesterol in BU patients and controls. (b) Absolute concentrations of serum cortisol in BU
patients versus controls (left), and patients with different ulcer category (right). Data are presented as box
and whiskers. *p < 0.05, **p < 0.01. sulfate and taurolithocholate 3-sulfate were significantly downregulated in patients with BU (Fig. 4). No
variation in bile acids was reported in patients with TB30. The reduced levels of bile acids in BU patients
may be indicative of decreased synthesis, increased intestinal absorption or urinary excretion. Since bile
acid synthesis requires contribution from the microbial community, they may also reflect changes in the
intestinal flora. sulfate and taurolithocholate 3-sulfate were significantly downregulated in patients with BU (Fig. 4). No
variation in bile acids was reported in patients with TB30. The reduced levels of bile acids in BU patients
may be indicative of decreased synthesis, increased intestinal absorption or urinary excretion. Since bile
acid synthesis requires contribution from the microbial community, they may also reflect changes in the
intestinal flora. Heme products. Heme, the most common porphyrin found in the human body, complexes with
cellular proteins to form hemoglobin, myoglobin and cytochromes. Heme is synthesized from glycine
and succinyl-CoA and can be oxidized into bilirubin and vasodilator carbon dioxide. In patients with
BU, heme levels trended higher compared to controls. Conversely, the heme catabolic products biliver-
din, bilirubin ZZ and EE were diminished in these subjects (Fig. 5 and Table 2). No such variation was Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 9 www.nature.com/scientificreports/ Figure 4. Decreased bile acids levels in the serum of BU patients. Differential serum levels of detected bile
acids in patients and controls, shown as box and whiskers and in the context of their metabolic pathways. Biochemicals in bold red were relatively increased in patients versus controls. Those in bold green were
relatively decreased. Those in grey were not detected. **p < 0.01, ***p < 0.001. Figure 4. Decreased bile acids levels in the serum of BU patients. Differential serum levels of detected bile
acids in patients and controls, shown as box and whiskers and in the context of their metabolic pathways. Biochemicals in bold red were relatively increased in patients versus controls. Those in bold green were
relatively decreased. Those in grey were not detected. **p < 0.01, ***p < 0.001. detected in patients with TB, possibly because M. www.nature.com/scientificreports/ tuberculosis possesses its own heme-degrading enzyme
MhuD, producing an unusual tetrapyrole called mycobilin33. The M. ulcerans MhuD gene orthologue
(MUL_4167) is a predicted pseudogene due to the introduction of premature stop codon34. Consistent
with this prediction, no metabolite with a mass corresponding to mycobilin was detected in the serum
of patients with BU. detected in patients with TB, possibly because M. tuberculosis possesses its own heme-degrading enzyme
MhuD, producing an unusual tetrapyrole called mycobilin33. The M. ulcerans MhuD gene orthologue
(MUL_4167) is a predicted pseudogene due to the introduction of premature stop codon34. Consistent
with this prediction, no metabolite with a mass corresponding to mycobilin was detected in the serum
of patients with BU. Riboflavin. Riboflavin (vitamin B2) was recently reported to be upregulated in mosquitoes exposed
to live M. ulcerans, compared to untreated mosquitoes or mosquitoes exposed to dead bacteria35. Interestingly in the present work, patients with BU also displayed increased levels of riboflavin (Table 2). Inspection of the M. ulcerans genome predicts an intact riboflavin anabolic pathway. M. ulcerans is pre-
dicted to possess intact inosine-5′ -monophosphate dehydrogenases (e.g. MUL_0901) and GMP synthase
(MUL_0913) and the subsequent enzymes to convert these molecules to GTP and enter the riboflavin
biosynthesis pathway. Increases in riboflavin are also consistent with the increased levels of the purine
metabolism intermediates, inosine and xanthine (see above). The enhanced detection of riboflavin in
infected hosts may thus reflect either bacterial growth, or the host response to infection. In any case, the Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 10 www.nature.com/scientificreports/ Figure 5. Decreased levels of heme catabolic products in the serum of BU patients. Differential serum
levels of biliverdin and bilirubin in patients and controls, shown as box and whiskers and in the context
of the heme metabolic pathway. Biochemicals in bold green were relatively decreased in patients versus
controls. Those in bold black were detected at comparable levels. Those in grey were not detected. *p < 0.05. Figure 5 Decreased levels of heme catabolic products in the serum of BU patients Differential serum Figure 5. Decreased levels of heme catabolic products in the serum of BU patients. Differential serum
levels of biliverdin and bilirubin in patients and controls, shown as box and whiskers and in the context
of the heme metabolic pathway. Biochemicals in bold green were relatively decreased in patients versus
controls. Those in bold black were detected at comparable levels. Those in grey were not detected. *p < 0.05. observation that riboflavin levels are associated with M. ulcerans infection in both humans and mosqui-
toes suggest that it could potentially serve as a pathogen-specific correlate of infection. Fibrinogen cleavage peptides. Upon vascular injury, soluble fibrinogen is cleaved into insoluble
fibrin, which is the main component of blood clots. Fibrinogen A-α cleavage peptides ADSGEGD
FXAEGGGVR and DSGEGDFXAEGGGVR were elevated in patients with BU (Supplementary Figure
S4 and Table 2), likely reflecting vascular remodeling in lesions. Comparable augmentations were seen in
patients with active TB and diabetes30,36, indicating that this process is not specific to BU. Lysolipids. Phospholipids (also called glycerophospholipids) are the main lipid constituents of cell
membranes. They are a highly diverse family of compounds containing diacylglycerol, a phosphate
head group and organic molecules like ethanolamine or choline. Lysolipids and fatty acids are the
natural products of their hydrolysis by phospholipases. Compared to controls, patients with BU dis-
played lower serum levels of choline and all detected lysophosphatidylcholine (LysoPC) compounds
(Fig. 6a and Table 2). Lysophosphatidylethanolamines (LysoPE) were comparably impacted. No such
variations were reported in patients infected with M. tuberculosis30, suggesting that they are spe-
cific to infection with M. ulcerans. In line with this hypothesis, several LysoPC compounds were
decreased in mosquitoes exposed to live but not killed preparations of the bacteria35. Together with Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 11 www.nature.com/scientificreports/ Figure 6. Decreased serum lysolipids in BU patients. (a) Differential levels of choline and representative
lysolipids in patients and controls, shown as box and whiskers and in the context of their metabolic pathway. Biochemicals in bold green were relatively decreased in patients versus controls. Those in bold black
were detected at comparable levels. Those in grey were not detected. (b) Differential levels of the detected
lysolipids in mycolactone- and vehicle-treated Jurkat T cells, presented as box and whiskers *p < 0.05,
**p < 0.01. Figure 6. Decreased serum lysolipids in BU patients. (a) Differential levels of choline and representative
l
li id i
ti
t
d
t
l
h
b
d
hi k
d i
th
t
t f th i
t b li
th Figure 6. Decreased serum lysolipids in BU patients. (a) Differential levels of choline and representative
lysolipids in patients and controls, shown as box and whiskers and in the context of their metabolic pathway. Biochemicals in bold green were relatively decreased in patients versus controls. Those in bold black
were detected at comparable levels. Those in grey were not detected. (b) Differential levels of the detected
lysolipids in mycolactone- and vehicle-treated Jurkat T cells, presented as box and whiskers *p < 0.05,
**p < 0.01. our observations in human patients, these data indicate that M. ulcerans interaction with its host
may alter phospholipid turnover in biomembranes. In T cells exposed to mycolactone, two LysoPC
species were decreased compared to controls (Fig. 6b and Table 3), suggesting that mycolactone may
contribute to these changes. Conclusion Here, we report the metabolomic profiles of serum samples of patients infected with M. ulcerans,
and mycolactone-exposed cells. Figure 7 summarizes our principal findings, and highlights which
metabolites/pathways were modulated in both BU patients and mycolactone-exposed cells. Among
them were hexoses, purine products and lysolipids, suggesting that mycolactone released by bacteria
interferes with blood cell production of biochemical energy, membrane lipid turnover and degradation Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 12 www.nature.com/scientificreports/ Figure 7. Metabolic alterations in patients with BU and mycolactone-exposed T cells partially overlap. Metabolic alterations are grouped by biochemical pathway/biochemical structure, within boxes entitled with
the corresponding metabolic pathway. In white: metabolites in this pathway were detected at higher levels in
BU patients vs controls, or mycolactone-treated cells vs controls. In black: inversely. Figure 7. Metabolic alterations in patients with BU and mycolactone-exposed T cells partially overlap. Metabolic alterations are grouped by biochemical pathway/biochemical structure, within boxes entitled with
the corresponding metabolic pathway. In white: metabolites in this pathway were detected at higher levels in
BU patients vs controls, or mycolactone-treated cells vs controls. In black: inversely. of nucleic acids. Interestingly, patients with BU also displayed distinctive downregulation of bile acids
and heme products, and upregulation of riboflavin in serum. Intermediates of these metabolic path-
ways may have potential as biomarkers of BU progression, and inspire new avenues for therapeutic
interventions. of nucleic acids. Interestingly, patients with BU also displayed distinctive downregulation of bile acids
and heme products, and upregulation of riboflavin in serum. Intermediates of these metabolic path-
ways may have potential as biomarkers of BU progression, and inspire new avenues for therapeutic
interventions. References 1. Yotsu, R. R. et al. Revisiting Buruli ulcer. J Dermatol; doi: 10.1111/1346-8138.13049. (2015). 2. Huang, G. K. & Johnson, P. D. Epidemiology and management of Buruli ulcer. Expert Rev Anti Infe 12, 855–865 (2014). 3. Lavender, C. J. et al. Risk of Buruli ulcer and detection of Mycobacterium ulcerans in mosquitoes in southeastern Australia. Negl Trop Dis 5, e1305 (2011). g
p
4. Merritt, R. W. et al. Ecology and transmission of Buruli ulcer disease: a systematic review. PLoS Negl Trop Dis 4, e911 (20 5. Walsh, D. S., Portaels, F. & Meyers, W. M. Buruli ulcer (Mycobacterium ulcerans infection). Trans R Soc Trop Med Hy
969–978 (2008). 6. Wansbrough-Jones, M. & Phillips, R. Buruli ulcer: emerging from obscurity. Lancet 367, 1849–1858 (2006).i g
p
g
g
y
7. Stinear, T. et al. Identification and characterization of IS2404 and IS2606: two distinct repeated sequences for detection o
Mycobacterium ulcerans by PCR. J Clin Microbiol 37, 1018–1023 (1999).fi 7. Stinear, T. et al. Identification and characterization of IS2404 and IS2606: tw
Mycobacterium ulcerans by PCR. J Clin Microbiol 37, 1018–1023 (1999).fi y
y
8. Etuaful, S. et al. Efficacy of the combination rifampin-streptomycin in preventing growth of Mycobacterium ulcerans in early
lesions of Buruli ulcer in humans. Antimicrob Agents Chemother 49, 3182–3186 (2005).fi 8. Etuaful, S. et al. Efficacy of the combination rifampin-streptomycin in preventing growt
lesions of Buruli ulcer in humans. Antimicrob Agents Chemother 49, 3182–3186 (2005).fi 9. Sarfo, F. S. et al. Clinical efficacy of combination of rifampin and streptomycin for treatment of Mycobacterium ulcerans disease
Antimicrob Agents Ch 54, 3678–3685 (2010). 9. Sarfo, F. S. et al. Clinical efficacy of combination of rifampin and streptomycin for treatm
Antimicrob Agents Ch 54, 3678–3685 (2010). 10. Guenin-Mace, L., Oldenburg, R., Chretien, F. & Demangel, C. Pathogenesis of skin ulcers: lessons from the Mycobacterium
ulcerans and Leishmania spp. pathogens. Cell Mol Life Sci (2014). ulcerans and Leishmania spp. pathogens. Cell Mol Life Sci (20 pp p
g
f
1. George, K. M., et al. Mycolactone: a polyketide toxin from Mycobacterium ulcerans required for virulence. Science 283, 854–857
(1999). 12. Stinear, T. P. et al. Giant plasmid-encoded polyketide synthases produce the macrolide toxin of Mycobacterium ulcerans. Proc
Natl Acad Sci USA 101, 1345–1349 (2004). 13. Hong, H., Demangel, C., Pidot, S. J., Leadlay, P. F. & Stinear, T. Mycolactones: immunosuppressive and cytotoxic polyketides
produced by aquatic mycobacteria. e e e ces
1. Yotsu, R. R. et al. Revisiting Buruli ulcer. J Dermatol; doi: 10.1111/1346-8138.13049. (2015). www.nature.com/scientificreports/ J Biol Chem 288, 10101–10109 (2013). 33. Nambu, S., Matsui, T., Goulding, C. W., Takahashi, S. & Ikeda-Saito, M. A new way to degrade heme: the Mycobacterium
tuberculosis enzyme MhuD catalyzes heme degradation without generating CO. J Biol Chem 288, 10101–10109 (2013). y
y
g
g
g
4. Stinear, T. P. et al. Reductive evolution and niche adaptation inferred from the genome of Mycobacterium ulcerans, the causative
agent of Buruli ulcer. Genome Res 17, 192–200 (2007).t agent of Buruli ulcer. Genome Res 17, 192–200 (2007). g
5. Hoxmeier, J. C. et al. Analysis of the metabolome of Anopheles gambiae mosquito after exposure to Mycobacterium ulcerans. Sc
Rep 5, 9242 (2015). g
35. Hoxmeier, J. C. et al. Analysis of the metabolome of Anopheles gambiae mosquito after exposure to Mycobacterium ulcerans. Sci
Rep 5, 9242 (2015). p
36. Suhre, K. et al. Metabolic footprint of diabetes: a multiplatform metabolomics study in an epidemiological setting. Plos One 5,
e13953 (2010). p
36. Suhre, K. et al. Metabolic footprint of diabetes: a multiplatform metabolomics study in an epidemiological setting. Plos One 5,
e13953 (2010). Acknowledgementsh The authors wish to thank Magnus Fontes (Institut Pasteur) for help with PCA analysis. This work was
supported by the Fondation de la Recherche Médicale (FRM 2012 DEQ20120323704), the Association
Raoul Follereau and the Région Ile de France (dim130027). Author Contributions C.D. and R.O.P. conceived the experiments; S.F., M.F., M.W.-J. and R.O.P. selected human participants
and collected samples; L.G.-M. performed the Jurkat T cell studies; F.N., T.S. and C.D. analyzed the data;
F.N. and C.D. prepared the figures and edited the text. All authors reviewed the manuscript. Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 References Nat Prod Rep 25, 447–454 (2008). p
y q
y
p
4. Demangel, C., Stinear, T. P. & Cole, S. T. Buruli ulcer: reductive evolution enhances pathogenicity of Mycobacterium ulcerans
Nat Rev Microbiol 7, 50–60 (2009).f 5. Hong, H. et al. Mycolactone diffuses from Mycobacterium ulcerans-infected tissues and targets mononuclear cells in periphera
blood and lymphoid organs. PLoS Negl Trop Dis 2, e325 (2008).f 16. Sarfo, F. S. et al. Mycolactone diffuses into the peripheral blood of buruli ulcer patients - implications for diagnosis and disease
monitoring. PLoS Negl Trop Dis 5, e1237 (2011). f
monitoring. PLoS Negl Trop Dis 5, e1237 (2011). g
g
p
7. Boulkroun, S. et al. Mycolactone suppresses T cell responsiveness by altering both early signaling and posttranslational events. Immunol 184, 1436–1444 (2010).l 8. Guenin-Mace, L. et al. Shaping mycolactone for therapeutic use against inflammatory disorders. Sci Transl Med 7, 289ra285
(2015). 19. Guenin-Mace, L. et al. Mycolactone impairs T cell homing by suppressing microRNA control of L-selectin expression. Proc Natl
Acad Sci USA 108, 12833–12838 (2011). 0. Simmonds, R. E., Lali, F. V., Smallie, T., Small, P. L. & Foxwell, B. M. Mycolactone inhibits monocyte cytokine production by a
posttranscriptional mechanism. J Immunol 182, 2194–2202 (2009).f 21. Hall, B. & Simmonds, R. Pleiotropic molecular effects of the Mycobacterium ulcerans virulence factor mycolactone underlying
the cell death and immunosuppression seen in Buruli ulcer. Biochem Soc Trans 42, 177–183 (2014). Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 13 www.nature.com/scientificreports/ www.nature.com/scientificreports/ 22. Hall, B. S. et al. The pathogenic mechanism of the Mycobacterium ulcerans virulence factor, mycolactone, depends on bloc
of protein translocation into the ER. PLoS Pathog 10, e1004061 (2014).ll p
g
23. Phillips, R. O. et al. Combined inflammatory and metabolic defects reflected by reduced serum protein levels in patients
Buruli ulcer disease. PLoS Negl Trop Dis 8, e2786 (2014). g
p
,
(
)
24. Fyfe, J. A. M. et al. Development and application of two multiplex real-time PCR assays for the detection of Mycobacterium
ulcerans in clinical and environmental samples. Appl Environ Microb 73, 4733–4740 (2007). p
pp
5. Phillips, R. et al. Sensitivity of PCR targeting the IS2404 insertion sequence of Mycobacterium ulcerans in an assay using punch
biopsy specimens for diagnosis of Buruli ulcer. J Clin Microbiol 43, 3650–3656 (2005).f y
g
6. Spangenberg, T. & Kishi, Y. Highly sensitive, operationally simple, cost/time effective detection of the mycolactones from the
human pathogen Mycobacterium ulcerans. Chem Commun 46, 1410–1412 (2010).h p
g
y
7. Owen, O. E., Kalhan, S. C. & Hanson, R. W. The key role of anaplerosis and cataplerosis for citric acid cycle function. J Biol Chem
277, 30409–30412 (2002). (
)
28. Rinaldo, P., Cowan, T. M. & Matern, D. Acylcarnitine profile analysis. Genet Med 10, 151–156 (2008). h
l
fl
fl
l 28. Rinaldo, P., Cowan, T. M. & Matern, D. Acylcarnitine profile 9. Schooneman, M. G., Vaz, F. M., Houten, S. M. & Soeters, M. R. Acylcarnitines: reflecting or inflicting insulin resistance? Diabete
62, 1–8 (2013).l 0. Weiner, J. et al. Biomarkers of inflammation, immunosuppression and stress with active disease are revealed by metabolomic
profiling of tuberculosis patients. Plos One 7(2012). pi
g
p
1. Lushchak, V. I. Glutathione homeostasis and functions: potential targets for medical interventions. J Amino Acids 2012, 736837
(2012). 2. Lefebvre, P., Cariou, B., Lien, F., Kuipers, F. & Staels, B. Role of bile acids and bile acid receptors in metabolic regulation. Physio
Rev 89, 147–191 (2009). 3. Nambu, S., Matsui, T., Goulding, C. W., Takahashi, S. & Ikeda-Saito, M. A new way to degrade heme: the Mycobacterium
tuberculosis enzyme MhuD catalyzes heme degradation without generating CO J Biol Chem 288 10101–10109 (2013) 33. Nambu, S., Matsui, T., Goulding, C. W., Takahashi, S. & Ikeda-Saito, M. A new way to degrade heme: the Mycobacterium
tuberculosis enzyme MhuD catalyzes heme degradation without generating CO. Additional Information Supplementary information accompanies this paper at http://www.nature.com/srepi Competing financial interests: The authors declare no competing financial interests.i Competing financial interests: The authors declare no competing financial interests.i How to cite this article: Niang, F. et al. Metabolomic profiles delineate mycolactone signature in
Buruli ulcer disease. Sci. Rep. 5, 17693; doi: 10.1038/srep17693 (2015). How to cite this article: Niang, F. et al. Metabolomic profiles delineate mycolactone signature in
Buruli ulcer disease. Sci. Rep. 5, 17693; doi: 10.1038/srep17693 (2015). This work is licensed under a Creative Commons Attribution 4.0 International License. The
images or other third party material in this article are included in the article’s Creative Com-
mons license, unless indicated otherwise in the credit line; if the material is not included under the
Creative Commons license, users will need to obtain permission from the license holder to reproduce
the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ Scientific Reports | 5:17693 | DOI: 10.1038/srep17693 14
|
https://openalex.org/W2021825655
|
https://link.springer.com/content/pdf/10.1007/JHEP01(2015)088.pdf
|
English
| null |
Top Partner Discovery in the T → tZ channel at the LHC
|
The Journal of high energy physics/The journal of high energy physics
| 2,015
|
cc-by
| 12,990
|
Received: October 22, 2014
Revised: December 2, 2014
Accepted: December 18, 2014
Published: January 16, 2015 Received: October 22, 2014
Revised: December 2, 2014
Accepted: December 18, 2014
Published: January 16, 2015 Received: October 22, 2014
Revised: December 2, 2014
Accepted: December 18, 2014
Published: January 16, 2015 Received: October 22, 2014
Revised: December 2, 2014
Accepted: December 18, 2014
Published: January 16, 2015 JHEP01(2015)088 Open Access, c⃝The Authors.
Article funded by SCOAP3. Top Partner Discovery in the T →tZ channel at
the LHC J¨urgen Reuter and Marco Tonini
DESY Theory Group,
Notkestr. 85, D-22607 Hamburg, Germany
E-mail: juergen.reuter@desy.de, marco.tonini@desy.de J¨urgen Reuter and Marco Tonini
DESY Theory Group,
Notkestr. 85, D-22607 Hamburg, Germany
E-mail: juergen.reuter@desy.de, marco.tonini@desy.de J¨urgen Reuter and Marco Tonini
DESY Theory Group,
Notkestr. 85, D-22607 Hamburg, Germany E-mail: juergen.reuter@desy.de, marco.tonini@desy.de Abstract: In this paper we study the discovery potential of the LHC run II for heavy
vector-like top quarks in the decay channel to a top and a Z boson. Despite the usually
smaller branching ratio compared to charged-current decays, this channel is rather clean
and allows for a complete mass reconstruction of the heavy top. The latter is achieved
in the leptonic decay channel of the Z boson and in the fully hadronic top channel using
boosted jet and jet substructure techniques. To be as model-independent as possible, a
simplified model approach with only two free parameters has been applied. The results
are presented in terms of parameter space regions for 3σ evidence or 5σ discovery for such
new states in that channel. 3
Setup of the analysis 4
Results 5
Conclusion 21 Keywords: Phenomenological Models, Monte Carlo Simulations Keywords: Phenomenological Models, Monte Carlo Simulations ArXiv ePrint: 1409.6962 Open Access, c⃝The Authors. Article funded by SCOAP3. Open Access, c⃝The Authors. Article funded by SCOAP3. doi:10.1007/JHEP01(2015)088 doi:10.1007/JHEP01(2015)088 Contents
1
Introduction
1
2
Top partners and top tagging
3
2.1
Models comprising top partners
3
2.2
Simplified model approach
7
2.3
Tagging the boosted regime
8
3
Setup of the analysis
9
3.1
Event generation
9
3.2
Reconstruction of physics objects
11
3.3
Cutflow
12
4
Results
17
5
Conclusion
21 Contents
1
Introduction
1
2
Top partners and top tagging
3
2.1
Models comprising top partners
3
2.2
Simplified model approach
7
2.3
Tagging the boosted regime
8
3
Setup of the analysis
9
3.1
Event generation
9
3.2
Reconstruction of physics objects
11
3.3
Cutflow
12
4
Results
17
5
Conclusion
21 1
3
3
7
8
9
9
11
12
17
21 1
3
3
7
8
9
9
11
12
17
21 JHEP01(2015)088 1
Introduction With the advent of the Large Hadron Collider (LHC), a whole new range of energies is
opening up for experimental particle physics, namely the range from the electroweak scale
v up to the multi-TeV regime. Within the first 2010-2012 run of the LHC crucial results
have been already collected, most notably the discovery of a (light) Higgs boson with mass
mh ∼125 GeV, publicly announced on the 4th of July 2012 [1, 2]. Also remarkable are
the (preliminary) measurements of the Higgs couplings and production modes, which are
turning out to be as predicted by the Standard Model: no significant sign of new phenomena
has been observed so far. This is starting to provide severe constraints on possible theories
that differ significantly from the Standard Model at the probed energies. Despite this enormous success, we know that the Standard Model cannot describe
all phenomena we have observed so far. In particular, the absence of a possible candi-
date to describe the Dark Matter and Dark Energy hinted by various cosmological and
astrophysical observations as well as the missing CP violation for the explanation of the
baryon-antibaryon asymmetry represent the main experimental results that cannot be ac-
commodated within the SM. Furthermore, different theoretical motivations are considered as issues of the actual
Standard Model formulation above the electroweak scale. The most notable one is the
fine-tuning problem: a light (fundamental) Higgs boson implies large accidental cancella-
tions between different and in principle uncorrelated physical quantities, due to its large
radiative sensitivity to possible higher scales in the theory. In a “natural” theory, large can-
cellations among uncorrelated terms should either not be present, or explained by means
of symmetry arguments. – 1 – The issue of a necessary fine-tuning to account for a light Higgs boson has always
been the main guideline for possible model building of Beyond the Standard Model (BSM)
Physics: suitable new phenomena should appear around the TeV energy scale in order to
suppress the large radiative corrections to the Higgs mass. The most sought-after solution
of the fine-tuning problem at the LHC is Supersymmetry (SUSY). An alternative solution
is given by strongly-coupled extensions of the Standard Model. In this class of models,
a new strong interaction sector in assumed at some energy above the electroweak scale,
making the Higgs a composite object below the compositeness scale. 1
Introduction Since it does not make
sense to speak of an elementary scalar Higgs boson above the compositeness scale, at low
energies the Higgs mass is thus at most sensitive to the value of the compositeness scale. In this sense, assuming a strong sector as UV-completion of the Standard Model prevents
dangerous fine-tuning requirements to account for the observed Higgs mass. However, in
a generic strongly interacting extension of the Standard Model, the compositeness scale
would be close to the Higgs mass, causing a conflict with electroweak precision observables
and direct searches for heavy resonances. JHEP01(2015)088 A consistent way to implement a strongly coupled UV-completion of the Standard
Model has led to models in which the Higgs arises as pseudo-Goldstone boson of some
spontaneously broken global symmetry of the strong sector at a scale f ≫v. The Higgs
boson can thus be much lighter than other possible states of the composite sector, in
complete analogy with the low-energy QCD description, where the pions arise as a set of
scalar states naturally lighter than the compositeness scale ΛQCD, with all other resonances
at higher masses. These models are generically called Composite Higgs models. In particular, light partners of the SM top are a key ingredient for the naturalness
argument of different BSM models, in order to cut offthe quadratic UV-sensitivity of the
Higgs mass squared parameter from SM top loops. This is a common feature for generic
Supersymmetric and Composite Higgs models. The main difference between supersym-
metric top partners (stops) and top partners arising in strongly coupled models is their
different spin, spin 0 vs. spin 1/2, respectively. The fermionic top partners are usually
vector-like particles. Contrary to sequential fourth-generation quarks, which are heavily constrained already
from Higgs boson searches, since they would yield a large impact e.g. in the one-loop induced
processes like gluon fusion production and diphoton decay of the Higgs, indirect bounds
on vector-like quarks are much weaker. Their effect on the Higgs observables is indeed less
dramatic than fourth generation quarks as their vector-like nature allows to obtain a large
Dirac mass without introducing a large Yukawa coupling to the Higgs. Both the ATLAS and CMS collaborations have recently performed dedicated searches
for top partners [3–10]. 1
Introduction Depending on the particular branching ratio under investigation,
the actual limits on the top partner mass, at √s = 8 TeV and with up to 20 fb−1 of inte-
grated luminosity, do not exceed 700–800 GeV. Most of these experimental searches assume
the new heavy quarks to be pair produced: however, searches combining pair production
with single production through electroweak interactions will become an important feature
in the future. Present limits from the LHC start to enter the region in which single produc-
tion becomes comparable to pair production due to the smaller phase space suppression,
even if an electroweak coupling is involved. – 2 – Many different theoretical analyses involving top partners have been recently proposed,
some of them exploiting tagging techniques [11–30]. However, a closer look to these refer-
ences reveals that the top partner decay T →Z t has not been thoroughly explored yet,
because it appears rather difficult at first glance. In particular, the all-hadronic final state
suffers from huge SM backgrounds, making the alternative T →W b channel more suited
for all-hadronic analyses due to the enhanced branching ratio and the possibility to exploit
b-tagging. Furthermore, the channel involving a leptonic decay of the Z entails a large
suppression from the Z leptonic branching ratio, BR(Z →ℓ+ℓ−) ∼0.067 (ℓ≡e, µ). A
study of the T →Z t “trilepton” channel with both leptonic decays of the Z boson and
top quark has been first proposed in [24] and recently published in [30]. JHEP01(2015)088 In order to test the nature of the top partner, it is important to develop search strategies
which might cover all possible channels, especially for the foreseen LHC energy upgrade to
13 TeV. For this reason, we develop a search strategy tailored for a charge-2/3 top partner
optimised for its decay channel T →t Z →(q q′ b) (ℓ+ℓ−), at the LHC with center-of-mass
energy of √s = 13 TeV and integrated luminosity of 300 fb−1. We present, with minimal
assumptions on the underlying model, a method to discover a possible top partner signature
with large statistical significance. More importantly, we aim at a precise measurement of
its invariant mass. Recently, ATLAS presented a √s = 8 TeV search [3, 4] optimised for either pair or
single production of a top partner, subsequently decaying as T →Z t with leptonic decay
of the Z boson. 1
Introduction This encouraged us to further analyse this rather unexplored process, in
order to provide an effective search strategy for the forthcoming 13 TeV LHC runs. The structure of the paper is the following. In section 2 we briefly review differ-
ent examples of models comprising top partners in the context of strongly coupled UV-
completions of the SM. This is followed by a discussion of a simplified-model approach for
the simulation of top partner signal events, and some details about top-tagging techniques
useful to tag the boosted regime of the top partner decay products. Section 3 presents the
setup of our proposed analysis, namely the event generation procedure, the reconstruction
of physics objects, and the definition of the dedicated selection cuts. Finally, a thorough dis-
cussion of the results is presented in section 4, together with concluding remarks in section 5. 2.1
Models comprising top partners All differences on the underlying top-partner model depend on the choice of the represen-
tation of the new quarks and on the assignment of the quantum numbers. We will briefly
discuss some examples of top partners in the context of strongly coupled UV-completions
of the SM. A prominent class of models predicting light spin-1/2 vector-like top partners is the
class of Composite Higgs models [16, 31–37]. In the minimal Composite Higgs scenario, the
coset structure is SO(5)/SO(4). The main guiding principle is that the decays and single
production of the new partners are generated via mixing with the standard quarks, induced
by Yukawa interactions with the Higgs. In particular, only the right-handed SM top quark – 3 – tR is promoted to a fully composite state belonging to a complete multiplet (singlet) of the
unbroken SO(4) group, while the (elementary) left-handed SM doublet qL is assumed to be
embedded into an incomplete SO(5) multiplet and to couple linearly to the strong sector. The vector-like top partners are introduced as composite bound states belonging to
a complete multiplet Ψ of the unbroken group SO(4): two cases are usually considered,
namely Ψ ∼4 or Ψ ∼1 under SO(4). We will refer to these two implementations as
M45 and M15, respectively. In the M45 case, the multiplet Ψ includes two charge-2/3
top partners X2/3, T, one exotic charge-5/3 top partner X5/3, and a charge-1/3 bottom
partner B: under the SM gauge group, the four components of Ψ decompose into two SM
doublets (T, B) and (X5/3, X2/3) of hypercharge 1/6 and 7/6, respectively. In the M15
case, only one SU(2)-singlet charge-2/3 top partner ˜T is introduced. JHEP01(2015)088 Assuming an embedding of the elementary SM doublet qL into an incomplete fun-
damental representation Q5
L ∼5 of SO(5), the following interactions involving the top
partners can be written down [16]: LM45 ⊃i c1
¯ΨR
i γµdi
µ tR + y f
¯Q5
L
I UI i Ψi
R + y c2 f
¯Q5
L
I UI 5 tR + h.c. (2.1)
LM15 ⊃y f
¯Q5
L
I UI 5 ΨR + y c2 f
¯Q5
L
I UI 5 tR + h.c. 2.1
Models comprising top partners (2.2) (2.1) (2.1)
(2.2) (2.1) (2.2) In particular, dµ is the connection symbol defined in the CCWZ formalism [38, 39], U is the
5 × 5 Goldstone boson matrix, y is a Yukawa coupling controlling the mixing between the
composite and elementary states, c1, c2 are O(1) parameters associated with the interac-
tions of tR, and f is the usual symmetry breaking scale of the strong sector. For the model
M15, a direct coupling of Ψ with tR like the first term in eq. (2.1) can be removed with
a field redefinition. Note that the operators proportional to y explicitly break the SO(5)
symmetry, since qL is embedded into an incomplete SO(5) multiplet, giving rise to the
leading contribution to the Higgs potential triggering the electroweak symmetry breaking. It turns out that the couplings of the top partners to the Goldstone bosons (φ±, φ0),
which in the high energy limit correspond to the longitudinal components of the gauge
bosons (Equivalence Theorem), and to the Higgs h, are proportional to linear combinations
of the couplings y, c [16]: M45 :
φ+ ¯X5/3 L tR
:
√
2 c1 gΨ
h + iφ0 ¯X2/3 L tR
: c1 gΨ
h −iφ0 ¯TL tR
: −c1
q
y2 + g2
Ψ +
c2 y2
√
2
q
y2 + g2
Ψ
φ−¯BL tR
: c1
√
2
q
y2 + g2
Ψ −
c2 y2
q
y2 + g2
Ψ
(2.3)
M15 :
h + iφ0 ¯˜TR tL
:
y
√
2
φ+ ¯˜TR bL
: y ,
(2.4) (2.3) (2.4) : y , where gΨ = MΨ/f, MΨ being the Dirac mass of the top partner multiplet. where gΨ = MΨ/f, MΨ being the Dirac mass of the top partner multiplet. These couplings govern the associated production of the different top partners. In par-
ticular we see that the SU(2)-singlet top partner ˜T can be copiously produced in association
with a b-quark: from eq. (2.4), its coupling to the W boson is given by mW
M˜T
· coeff
φ+ ¯˜TR bL
=
mW
M˜T
y ≡g g∗
√
2 ,
(2.5) (2.5) with y of order O(1) to reproduce the SM top mass. Furthermore, we can easily read offfrom eq. 2.1
Models comprising top partners (2.3) and (2.4) the different branching
ratios of all top partners. For example, in the decoupling limit of mΨ →∞, the branching
ratios of the M15 SU(2)-singlet top partner ˜T are JHEP01(2015)088 BR
˜T →W b
∼0.5 ,
BR
˜T →Z t
∼0.25 ,
BR
˜T →h t
∼0.25 ,
(2.6) (2.6) while the branching ratios of the charge-2/3 top partners of M45 are given by BR(X2/3 →Z t) ∼BR(T →Z t) ∼0.5 ,
BR(X2/3 →h t) ∼BR(T →h t) ∼0.5 . (2.7) (2.7) Besides the composite Higgs models, there are other models predicting an SU(2)-singlet
top partner, e.g. Little Higgs models. A prime example is the Littlest Higgs Model with
T-parity (LHT) [40–42]. Within the class of strongly coupled UV-completions of the SM,
Little Higgs models represent an appealing realisation exploiting a natural separation be-
tween the electroweak scale v and the compositeness scale Λ = 4πf. This is realised through
Collective Symmetry Breaking. This mechanism forces the global symmetries, preventing
the generation of a Higgs mass term, to be broken by at least two operators: in this way,
the Higgs mass-generating one-loop diagrams are at most logarithmically divergent in Λ,
while quadratically divergent only at two-loop level. The realisation of this mechanism
requires the introduction of additional partner fields in the scalar, vector boson and top
sectors, in order to formulate “collective” couplings of the Higgs boson to the SM particles
and their respective partners. The Littlest Higgs model is based on a non-linear sigma model describing the global
spontaneous symmetry breaking at the scale f ∼O(TeV) SU(5)/SO(5) . (2.8) SU(5)/SO(5) . (2.8) The mechanism for this symmetry breaking is not specified: the model describes an effective
theory valid up to the compositeness scale Λ = 4πf, where a strong sector as UV-completion
is assumed. For comprehensive reviews of the model details see [43–48]. In here we just
mention that, in addition to the SM particles, new charged heavy vector bosons (W ±
H ), a
neutral heavy vector boson (ZH), a heavy photon (AH), a top partner (T+) and a triplet
of scalar heavy particles (Φ) are present: these heavy particles acquire masses of order f – 5 – from the SU(5)/SO(5) spontaneous breaking. Couplings of the Higgs to these particles
radiatively generate a potential for the Higgs boson, triggering the electroweak symmetry
breaking. As the original Littlest Higgs model suffers from severe constraints from electroweak
precision tests (EWPT), which could be satisfied only in rather extreme regions of the
parameter space [49–51], these can be evaded with the introduction of a custodial symmetry,
ungauging some of the symmetries [52, 53], or with the introduction of a conserved discrete
symmetry called T-parity [41, 42]. Using the latter, the scale f can be as low as O(500 GeV),
resulting in a rather low amount of fine-tuning to accommodate the observed Higgs mass,
together with not too suppressed production cross sections of new particles [45, 51, 54, 55]. JHEP01(2015)088 Recent studies including constraints from EWPT, Higgs observables and results from
direct searches for new particles, have set a lower bound on the scale f to be [51, 56, 57] (fLHT, A)EWPT+Higgs ≳694 GeV
(2.9)
(fLHT, B)EWPT+Higgs ≳560 GeV ,
(2.10) (2.9) (2.10) depending on the particular implementation of the down Yukawa couplings. The latter
translate into e.g. a lower bound on the mass of the top partner depending on the particular implementation of the down Yukawa couplings. The latter
translate into e.g. a lower bound on the mass of the top partner MT+
LHT, A ≳975 GeV
(2.11)
MT+
LHT, B ≳787 GeV . (2.12) (2.11)
(2 12) (2.11) (2.11)
(2.12) (2.12) Besides the (T-even) top partner T+, which is introduced to regularise the quadratic
divergence of the Higgs mass from the SM top loop, a consistent implementation of T-
parity in the top sector requires the introduction of a T-odd counterpart of the heavy
top partner, called T−, and a T-odd partner of the (T-even) SM top, called tH. SU(5)/SO(5) . JHEP01(2015)088 Table 1. Overview of the decay modes with the corresponding branching ratios of the LHT new
quarks, with reference values f = 1 TeV and R = 1.0 [56, 57]. We emphasise two possible scenarios,
namely with the mirror quarks qH either lighter (κ = 0.4) or heavier (κ = 1.0) than the gauge
boson partners. The heavy leptons decay analogously to the heavy quarks and the decays involving
generic up or down quarks have to be considered as summed over all flavours. From this, it is clear that charge-2/3 vector-like top partners share similar final state
topologies, with different branching ratios and single production couplings depending on
the particular underlying model. Therefore, when looking for possible dedicated searches
for top partners at the LHC, it is favourable to use simplified model approaches, involving
for example only the mass of the top partner and its “single production” coupling as free
parameters. We pursue this approach for the rest of the paper. SU(5)/SO(5) . While the
introduction of the former is specific for the top sector, every SM fermion is instead required
to possess a T-odd partner, generically called mirror fermion. Both T+ and T−acquire a
mass of order f from a Yukawa-like Lagrangian, as well as the SM top after electroweak
symmetry breaking; on the other hand, the mass generation for mirror fermions requires
the introduction of a Lagrangian involving couplings proportional to a new free parameter
κ. R is a ratio of Yukawa couplings in the top sector (for more details, c.f. e.g. [51]). κ. R is a ratio of Yukawa couplings in the top sector (for more details, c.f. e.g. [51]) In table 1 we list an overview of decay modes and branching ratios of the LHT new
particles, with reference values f = 1 TeV and R = 1.0. In particular, the LHT T+ top
partner shares the 2:1:1 ratio for the decays into SM particles as in eq. (2.6), but allows for
a further decay channel involving the T-odd partner T−and the heavy photon AH with a
non-negligible rate. The electroweak coupling of T+ to the W boson, which governs its associated produc-
tion with a b-quark, is given by [48] coeff
W + ¯T+ R bL
= g
√
2
R2
1 + R2
v
f + O
v2
f2
≡g g∗
√
2 . (2.13) (2.13) Note that we again put this into the same form as eq. (2.5). Note that we again put this into the same form as eq. (2.5). – 6 – Particle
Decay
BRκ=1.0
BRκ=0.4
dH
W −
H u
63%
0%
ZH d
31%
0%
AH d
6%
100%
uH
W +
H d
61%
0%
ZH u
30%
0%
AH u
9%
100%
T+
W + b
46%
46%
Z t
22%
22%
H t
21%
21%
T−AH
11%
11%
T−
AH t
100%
100%
Table 1. Overview of the decay modes with the corresponding branching ratios of the LHT new
quarks, with reference values f = 1 TeV and R = 1.0 [56, 57]. We emphasise two possible scenarios,
namely with the mirror quarks qH either lighter (κ = 0.4) or heavier (κ = 1.0) than the gauge
boson partners. The heavy leptons decay analogously to the heavy quarks and the decays involving
generic up or down quarks have to be considered as summed over all flavours. 2.2
Simplified model approach Recently, a generic parametrisation of an effective Lagrangian for top partners has been
proposed in [58], where the authors considered vector-like quarks embedded in different
representations of the weak SU(2) group, with other minimal assumptions regarding the
structure of the couplings. In particular, vector-like quarks which can mix and decay
directly into SM quarks of all generations are included. Particularly interesting for our
purposes is the case in which the top partner is an SU(2) singlet, with couplings only to
the third generation of SM quarks. The Lagrangian parametrising the possible top partner
interactions reads [58] LT ⊃g∗
√
2
g
√
2
¯TL W +
µ γµ bL +
g
2cW
¯TL Zµγµ tL −MT
v
¯TR h tL −mt
v
¯TL h tR
+ h.c. ,
(2.14) (2.14) where MT is the top partner mass, and g∗parametrises the single production coupling
in association with a b- or a top-quark. In the limit of MT ≫mt, the width of the top – 7 – partner is partner is ΓT ≃(g g∗)2 M3
T
64 π m2
W
1 + 1
2 + 1
2
,
(2.15) (2.15) where the three contributions in parentheses arise from the top partner decays to W, Z
and Higgs, respectively. The different branching ratios of T are thus clearly the same as in
eq. (2.6), since we are describing effectively the same type of top partner as in M15. For our proposed top partner search at the LHC we will exploit a simplified-model
approach, assuming the interactions described by the Lagrangian of eq. (2.14), where the
only free parameters will be the top partner mass MT and its “single production” coupling
g∗. In this way, our results will be straightforwardly mapped within the context of the
M15 minimal Composite Higgs model, namely by identifying as in eq. (2.5) JHEP01(2015)088 y = g g∗
√
2
M˜T
mW
(M15) . (2.16) (2.16) For comparison, with y = 1 and M˜T = 1 TeV one obtains g∗∼0.17. r comparison, with y = 1 and M˜T = 1 TeV one obtains g∗∼0.17. On the other hand, while an immediate map of g∗to the LHT parameters is straight-
forward from eq. (2.13), namely with g∗=
√
2
R2
1 + R2
v
f + O
v2
f2
(LHT) ,
(2.17) (2.17) the Lagrangian of eq. 2.2
Simplified model approach (2.14) does not exactly reproduce the T+ phenomenology because of
the absence of the T+ →T−AH vertex in the simplified-model approach. In particular, it
should be kept in mind that the different branching ratios of the top partner described by
eq. (2.14) slightly overestimate the actual branching ratios of the LHT T+ partner. For
comparison, fixing R = 1.0 and f = 1 TeV yields g∗∼0.17. the Lagrangian of eq. (2.14) does not exactly reproduce the T+ phenomenology because of
the absence of the T+ →T−AH vertex in the simplified-model approach. In particular, it
should be kept in mind that the different branching ratios of the top partner described by
eq. (2.14) slightly overestimate the actual branching ratios of the LHT T+ partner. For
comparison, fixing R = 1.0 and f = 1 TeV yields g∗∼0.17. Finally, by using the simplified-model approach, we also underestimate the branching
ratios of the charge-2/3 top partners within the M45 model, given in eq. (2.7): our results
will be conservative in this case. 2.3
Tagging the boosted regime Let us now focus on the kinematics of a possible top partner decay. For masses much
heavier than the top quark, the top partner decay products are produced with large spa-
tial separation (back-to-back decay). Furthermore, for large center-of-mass energies, these
primary top partner decay products are necessarily boosted, namely with transverse mo-
mentum pT which considerably exceeds their rest mass: this means that the subsequent
decay products are highly collimated in one area of the detector. As a rule of thumb, the
decay products of a highly boosted particle of mass m and transverse momentum pT ≫m
are collimated within a cone of radius ∆R ∼2 m
pT
,
(2.18) (2.18) such that e.g. the hadronic decays of a boosted SM top with pT ∼250 GeV are collimated
within a detector region of radius ∆R ≲1.4. such that e.g. the hadronic decays of a boosted SM top with pT ∼250 GeV are collimated
within a detector region of radius ∆R ≲1.4. – 8 – In this kinematical regime, conventional reconstruction algorithms that rely on a jet-
to-parton assignment are often not feasible. Crucial ingredients for high center-of-mass
searches involving massive particles are the so-called substructure methods [59, 60], to
identify the top partner decay products within large “fat” jets. Generically, focusing on
hadronic decays of boosted objects, these substructure methods first reconstruct jets with a
much larger radius parameter, in order to capture the energy of the complete hadronic decay
in a single jet; then use method-dependent discriminating variables to analyse the internal
structure of the fat jets, to separate boosted objects from the large QCD background. Jet-substructure methods which are dedicated to the identification of possible boosted
tops are generically called top-taggers. In particular, top tagging techniques are crucial not
only to reduce the huge SM QCD and t¯t backgrounds, exploiting the particular kinematical
feature of the boosted decay products, but also to avoid combinatorics in the reconstruction
of the top four momentum from high multiplicity final-state jets. In this way, fully-hadronic
top decays with a larger branching ratio compared to leptonic final states, can be systemat-
ically exploited for searches involving top partners. A review on top-taggers can be found
e.g. in [61]. JHEP01(2015)088 It turns out, see e.g. refs. [6, 25], that the Heidelberg-Eugene-Paris top-tagger [60]
(“HEPTopTagger”) can have a relatively better performance compared to other algorithms,
especially for moderately boosted tops. 2.3
Tagging the boosted regime For this reason, in our analysis we will adopt the
HEPTopTagger to tag boosted top quarks in the considered signal events. 3.1
Event generation As mentioned in section 2, we investigate processes involving a charge-2/3 vector-like top
partner T, inclusively pair and associated produced, with subsequent decay As mentioned in section 2, we investigate processes involving a charge-2/3 vector-like top
partner T, inclusively pair and associated produced, with subsequent decay T →t Z →
q q′ b
ℓ+ℓ−
. (3.1) (3.1) The process is depicted in figure 1 together with our conditions on the cones of the boosted
objects to be defined below. We study a possible search strategy optimised for the LHC with
center-of-mass energy of √s = 13 TeV and integrated luminosity of 300 fb−1. The clean
final state and the absence of missing transverse energy makes this channel promising for
a possible mass reconstruction of the top partner, even if the possible SM backgrounds are
rather huge. Signal and background events have been simulated using MadGraph5 v2.1 [62], and
Pythia 8.183 [63] for parton-shower and fragmentation, and further analysed via Delphes
3.1 [64] for a fast detector simulation following the specifications which we are going to
detail in the following. All cross sections have been checked with WHIZARD v2.2 [65–67]. In particular, an anti-kt jet clustering algorithm with radius parameter of R = 0.4 is used
to reconstruct jets, which in the following we will call slim jets. The same Pythia output
is simultaneously analysed through FastJet 3.0.6 [68, 69] in order to cluster the hadronic
activity using the Cambridge-Aachen algorithm with larger radius parameter of R = 1.5,
reconstructing jets which in the following we will identify as fat jets. – 9 – T
W ±
t
Z
∆R < 1.4
∆R < 1.0
b
q
q′
ℓ−
ℓ+
b
q′′
q′′′
Figure 1. Single production of a heavy top partner T with subsequent decay into tZ. The boosted
decay products of the latter are collected inside cones of ∆R < 1.4 and ∆R < 1.0, respectively. JHEP01(2015)088 Figure 1. Single production of a heavy top partner T with subsequent decay into tZ. The boosted
decay products of the latter are collected inside cones of ∆R < 1.4 and ∆R < 1.0, respectively. The model file generating signal events according to the Lagrangian of eq. (2.14) [58],
can be found in the dedicated FeynRules model database webpage (“Singlet T Model
VLQ”) [70–72]. 3.1
Event generation The corresponding free parameters are the top partner mass MT, the
coupling g∗which governs the top partner single production involving a t-channel W, and
the rate RL of T decays into light quarks. We fix RL = 0 in order to force T to decay only
to third generation SM quarks. For our analysis we consider values in the range MT ∈[850, 1450] GeV ,
g∗∈[0.05, 0.5] . (3.2) (3.2) In particular, our signal processes consist of pair and associated production of a charge-
2/3 vector-like top partner T, with subsequent decay as in eq. (3.1): in the case of pair
production we consider the inclusive decay of the second top partner according to the
branching ratios reported in eq. (2.6). The LO signal cross section is calculated via MG5,
depending on the particular choice of the free parameters which were consistently updated,
together with the top partner width, before the event generation. We further rescale
the signal cross section with a K-factor which we evaluate using Hathor 2.0 [73, 74]. In
particular, we calculate the K-factors for both top pair (NNLO) and single productions
(NLO) for different values of the top mass in the range (3.2), eventually choosing a minimal
and hence conservative value of K = 1.14. The main SM background processes turn out to be Z + jets, associated Z production
with a pair of top quarks (t¯t Z + jets), plus subleading contributions from associated Z
production with single top (t/¯t Z + jets). All other potentially dangerous contributions
like t¯t + jets, t¯t W ± + jets and γ∗→ℓ+ℓ−+ jets turn out to be negligible by requiring
exactly two opposite charge and same flavour leptons in the final state with invariant mass
satisfying |mℓ+ℓ−−mZ| < 10 GeV. Furthermore, the large W ±Z+ jets background becomes
also negligible due to the smaller boost of the Z boson compared to the signal and the
backgrounds involving the top quark, and by exploiting b- and top-tagging. – 10 – bkg. process
K-factor
Ref. Z + jets
1.20
[78]
t¯t Z + jets
1.30
[79]
t Z + jets
1.11
[80]
¯t Z + jets
1.09
[80]
Table 2. K-factors of the leading SM background processes for our analysis. Table 2. K-factors of the leading SM background processes for our analysis. 3.1
Event generation Large samples of background events are generated using MG5, requiring up to three,
two or one additional hard jets at matrix element level for Z + jets, t/¯t Z + jets and
t¯t Z + jets processes, respectively. To avoid double counting of jets generated at matrix
element level and jets radiated during the parton showering process, a CKKW-L merging
procedure [75–77] is exploited. In particular we interface, for each background sample,
the corresponding parton level MG5 outputs with different multiplicities of additional jets
to Pythia 8.183 and its internally built-in routines for the CKKW-L merging, accordingly
setting the merging scale value and the number of additional jets available from matrix
element. This procedure guarantees a correct prediction for the (merged) cross section of
the desired process. JHEP01(2015)088 We rescale the evaluated background cross sections with appropriate K-factors from
the corresponding publications, summarising the values in table 2. It should be noted
that the inclusive t¯t Z + jets K-factor as given in [79] is K = 1.39: however, this value is
reduced for large top transverse momenta, as in our case. For this reason we conservatively
set K = 1.30 as in table 2. 3.3
Cutflow Events are required to contain in the final state at least two leptons with minimum trans-
verse momentum pℓ
T > 25 GeV. Among all possible pairs of leptons, we require at least one
pair to consist of opposite charge and same flavour leptons matching the invariant mass of
the Z boson, namely such that the lepton-pair invariant mass mℓ+ℓ−satisfies |mℓ+ℓ−−mZ| < 10 GeV . (3.3) (3.3) We further require that, for at least one pair, the separation ∆R =
p
∆φ2 + ∆η2 between
the two candidate leptons reconstructing the Z mass should satisfy We further require that, for at least one pair, the separation ∆R =
p
∆φ2 + ∆η2 between
the two candidate leptons reconstructing the Z mass should satisfy We further require that, for at least one pair, the separation ∆R =
p
∆φ2 + ∆η2 between
the two candidate leptons reconstructing the Z mass should satisfy ∆R
ℓ+, ℓ−
< ∆R
ℓ+, ℓ−
max = 1.0 . (3.4) (3.4) If more than one pair of leptons satisfies the previous requirements, we select the pair
with invariant mass closest to the Z boson mass. This pair of leptons allows us to fully
reconstruct the four-momentum of the candidate Z boson. If more than one pair of leptons satisfies the previous requirements, we select the pair
with invariant mass closest to the Z boson mass. This pair of leptons allows us to fully
reconstruct the four-momentum of the candidate Z boson. The cut of eq. (3.4) is particularly effective to suppress SM backgrounds containing a
Z boson, since it captures the expected boosted kinematics of the Z boson from the top
partner decay. According to eq. (2.18), we expect indeed highly collimated decay products
from a boosted Z. On the other hand, SM processes do not provide a large transverse
boost to the Z boson, guaranteeing a good discrimination power to eq. (3.4). We show in figure 2 the distribution of the variable ∆R evaluated among candidate
leptons reconstructing the Z boson, for the different background and signal processes: a
peak at smaller values of ∆R is clearly visible for signal events. Note that the signal events
used for all distribution plots shown in this section correspond to the benchmark point
MT = 1 TeV and g∗= 0.1. 3.2
Reconstruction of physics objects Final state object reconstruction is performed mainly following the specifications detailed
in [81]. An electron candidate is required to have a transverse momentum pe
T ≥20 GeV
and |ηe| < 2.47. An isolation requirement is further applied, namely the total pT of all
charged particles q satisfying pq
T > 1.0 GeV and ∆R(e, q) < 0.3, should be less than 10%
of pe
T. A muon candidate is required to satisfy pµ
T ≥10 GeV and |ηµ| < 2.5. The isolation
for the muon requires that the total pT of all charged particles q satisfying pq
T > 1.0 GeV
and ∆R(µ, q) < 0.4, should be less than 6% of pµ
T. As mentioned before, slim jets are clustered from all final state particles with |η| < 4.9,
except isolated leptons and neutrinos, using the anti-kt algorithm with a radius parameter
of R = 0.4 as implemented in Delphes 3.1. Only slim jets with pj
T ≥20 GeV are further
considered. Slim jets are possibly identified as b-jets through the built-in Delphes 3.1
dedicated routines: in particular, we set the probability to tag b-jets (b-tag efficiency) to
70%, together with a charm quark misidentification probability of 10%. Tagged b-jets are
further required to be reconstructed within |ηb| < 2.5. Fat jets are simultaneously clustered using FastJet 3.0.6 on the same final state par-
ticles with |η| < 4.9, except isolated leptons and neutrinos, using the Cambridge-Aachen
algorithm with radius parameter of R = 1.5. Only fat jets with pj
T ≥20 GeV are fur-
ther considered. – 11 – Figure 2. Distribution of the ∆R variable evaluated among candidate leptons reconstructing the
Z boson for different processes. The signal process assumes MT = 1 TeV and g∗= 0.1. JHEP01(2015)088 Figure 2. Distribution of the ∆R variable evaluated among candidate leptons reconstructing the
Z boson for different processes. The signal process assumes MT = 1 TeV and g∗= 0.1. 3.3
Cutflow Further kinematic constraints are imposed on the candidate Z boson, again to exploit
the boosted properties of the considered signal. In particular, we require a large transverse – 12 – Figure 3. Distribution of the psudorapidity |ηZ| of the reconstructed candidate Z boson for different
processes. The signal process assumes MT = 1 TeV and g∗= 0.1. JHEP01(2015)088 Figure 3. Distribution of the psudorapidity |ηZ| of the reconstructed candidate Z boson for different
processes. The signal process assumes MT = 1 TeV and g∗= 0.1. omentum of the candidate Z, namely momentum of the candidate Z, namely momentum of the candidate Z, namely pZ
T > pZ
T, min = 225 GeV ,
(3.5) (3.5) as well as requiring that the Z should be produced in the central region of the detector,
namely with |ηZ| < |ηZ|max = 2.3 . (3.6) (3.6) The requirement of eq. (3.6) is useful in rejecting e.g. the SM Z + jets background, the
latter being mostly produced via a Drell-Yan process with the initial quarks yielding a
forward boost to the produced Z boson, as can be seen in figure 3. The requirement of eq. (3.6) is useful in rejecting e.g. the SM Z + jets background, the
latter being mostly produced via a Drell-Yan process with the initial quarks yielding a
forward boost to the produced Z boson, as can be seen in figure 3. In figure 4 we show the distribution of the transverse momentum of reconstructed Z
boson candidates as described in the text. Larger transverse momenta are observed for the
(boosted) Z from the signal process. In the next step, the hadronic activity is considered for additional selection cuts. In
order to account for the large boost of the top quark, we expect the final state jets to possess
a large amount of transverse momentum. Therefore, we evaluate the HT variable, namely
the scalar sum of the transverse momenta of the reconstructed slim jets with pj
T > 30 GeV
and within |ηj| < 3.0, requiring each event to satisfy HT > HT, min = 400 GeV . (3.7) (3.7) In figure 5 we show the HT distribution for the different considered processes. The
signal distribution has a considerable tail for larger values of HT compared to background
events, confirming the good discrimination power of eq. (3.7). It is also worth noticing
that the HT distribution for the signal in figure 5 displays two different visible peaks,
at O(500 GeV) and at O(1.3 TeV): these correspond to the top partner single and pair
production components of the signal, respectively. – 13 – Figure 4. Distribution of the transverse momentum pZ
T of the reconstructed candidate Z boson
for different processes. The signal process assumes MT = 1 TeV and g∗= 0.1. JHEP01(2015)088 Figure 4. Distribution of the transverse momentum pZ
T of the reconstructed candidate Z boson
for different processes. The signal process assumes MT = 1 TeV and g∗= 0.1. Figure 5. momentum of the candidate Z, namely Distribution of the scalar sum of the transverse momenta HT of the clustered slim jets
for different processes. The signal process assumes MT = 1 TeV and g∗= 0.1. Figure 5. Distribution of the scalar sum of the transverse momenta HT of the clustered slim jets
for different processes. The signal process assumes MT = 1 TeV and g∗= 0.1. Among the reconstructed final state slim jets, we further require the presence of at
least one tagged b-jet with pb
T > pb
T, min = 40 GeV . (3.8) (3.8) We then turn our attention to the reconstructed fat jets in the final state: our aim is
to identify one reconstructed fat jet as our top candidate. At least one fat jet is required
to be reconstructed among final state particles, satisfying the definition of fat jets given
before, and with an additional requirement on its transverse momentum being pJ
T > pJ
T, min = 200 GeV . (3.9) (3.9) – 14 – – 14 – Figure 6. Distribution of the transverse momentum pt
T of the reconstructed candidate top for
different processes. The signal process assumes MT = 1 TeV and g∗= 0.1. JHEP01(2015)088 Figure 6. Distribution of the transverse momentum pt
T of the reconstructed candidate top for
different processes. The signal process assumes MT = 1 TeV and g∗= 0.1. Most importantly, we require at least one fat jet to be HEPTop-tagged: the presence of
a boosted SM top from the decay of a heavier resonance is indeed one of the main features
of the signal. As mentioned in section 2, top tagging is crucial not only as a discriminant
against SM backgrounds, but also to effectively deal with the combinatorics in the top
reconstruction from high multiplicity final state jets. If more than one fat jet is identified
as a (boosted) top jet via the HEPTopTagger algorithm, we identify our candidate top as
the fat jet mostly back-to-back with respect to the previously reconstructed candidate Z
direction, as we would expect from the signal topology. To account for its boosted kinematics, we require that the transverse momentum of
the candidate top should satisfy the cut pt
T > pt
T, min = 250 GeV . (3.10) (3.10) The pt
T distribution of signal and background processes, after applying the cut of eq. momentum of the candidate Z, namely (3.10),
is shown in figure 6: a large fraction of signal events is observed for higher values of pt
T. Finally, to ensure that at least one of the tagged b-jets is originating from the candidate
top, and not from additional radiation or as decay product of another involved particle, we
require that the spatial separation between the candidate top and at least one of the slim
jets tagged as b-jet should satisfy ∆R(t, b) < ∆R(t, b)max = 0.8 . (3.11) (3.11) In other words, this cut ensures that at least one (slim) b-jet lies within the decay-cone of
the candidate (fat jet) top. To summarise the applied cuts, in table 3 we categorise them according to the recon-
structed object on which they are applied. It should be noted that the actual values of
∆R(ℓ+, ℓ−)max, pZ
T, min, |ηZ|max, HT, min, pb
T, min are identified using an optimisation pro-
cedure: in particular, we scan the aforementioned cut values within appropriate ranges – 15 – selection cuts
reconstructed Z
nℓ+ℓ−≥1
|mℓ+ℓ−−mZ| < 10 GeV
∆R(ℓ+, ℓ−) < 1.0
pZ
T > 225 GeV
|ηZ| < 2.3
slim jets
HT > 400 GeV
nb ≥1, pb
T > 40 GeV
fat jets
nJ ≥1, pJ
T > 200 GeV
HEPTop nt ≥1
pt
T > 250 GeV
∆R(t, b) < 0.8
Table 3. Summary of the selection cuts of the proposed analysis, sorted per type of reconstructed
object on which the cut is applied. selection cuts
reconstructed Z
nℓ+ℓ−≥1
|mℓ+ℓ−−mZ| < 10 GeV
∆R(ℓ+, ℓ−) < 1.0
pZ
T > 225 GeV
|ηZ| < 2.3
slim jets
HT > 400 GeV
nb ≥1, pb
T > 40 GeV
fat jets
nJ ≥1, pJ
T > 200 GeV
HEPTop nt ≥1
pt
T > 250 GeV
∆R(t, b) < 0.8
Table 3. Summary of the selection cuts of the proposed analysis, sorted per type of reconstructed
object on which the cut is applied. JHEP01(2015)088 Table 3. Summary of the selection cuts of the proposed analysis, sorted per type of reconstructed
object on which the cut is applied. able 3. Summary of the selection cuts of the proposed analysis, sorted per type of reconstructed
ject on which the cut is applied. momentum of the candidate Z, namely selection cut
signal
t¯t Z + jets
t Z + jets
nℓ+ℓ−, mℓ+ℓ−, ∆R(ℓ+, ℓ−)
40.5%
9.0%
4.9%
pZ
T > pZ
T, min
96%
69%
68%
|ηZ| < |ηZ|max
99%
99%
99%
HT > HT, min
80%
64%
61%
nb ≥1, pb
T > pb
T, min
77%
72%
55%
nJ ≥1, pJ
T > pJ
T, min
99%
96%
97%
HEPTop nt ≥1
40%
36%
29%
pt
T > pt
T, min
95%
82%
85%
∆R(t, b) < ∆R(t, b)max
80%
67%
79%
final efficiency
7.4%
0.5%
0.2%
production cross section [pb]
1.2 · 10−3
3.0 · 10−2
1.9 · 10−2
Table 4. Efficiencies of the selection cuts evaluated on the considered processes. In particular, the
signal events have been generated for the benchmark scenario MT = 1 TeV, g∗= 0.1. Table 4. Efficiencies of the selection cuts evaluated on the considered processes. In particular, t
signal events have been generated for the benchmark scenario MT = 1 TeV, g∗= 0.1. Table 4. Efficiencies of the selection cuts evaluated on the considered processes. In particular, the
signal events have been generated for the benchmark scenario MT = 1 TeV, g∗= 0.1. and evaluate the corresponding signal and background efficiencies for each possible con-
figuration, obtaining a signal over background (S/B) map as a function of the cut values. We then identify the optimal cut configuration yielding the highest S/B ratio, assuming
MT = 1 TeV and g∗= 0.1 for the signal, and making sure that the total number of events
after applying the cuts would remain reasonably large for 300 fb−1 of integrated luminosity. and evaluate the corresponding signal and background efficiencies for each possible con-
figuration, obtaining a signal over background (S/B) map as a function of the cut values. We then identify the optimal cut configuration yielding the highest S/B ratio, assuming
MT = 1 TeV and g∗= 0.1 for the signal, and making sure that the total number of events
after applying the cuts would remain reasonably large for 300 fb−1 of integrated luminosity. In table 4 we collect the resulting efficiencies evaluated on the different processes,
together with the corresponding production cross sections before the application of the cuts. – 16 – A final remark is devoted to possible pile-up effects, which we have not explicitly
included in our analysis. momentum of the candidate Z, namely It is expected that at the increased LHC center-of-mass energy
runs and higher integrated luminosity, an average of more than 50 interactions per proton-
bunch crossing will be observed. In particular, pile-up contamination might shift mass
distributions to higher values and broaden them. Since its effect scales as the jet area, jets
with larger cone area are more susceptible to pile-up contamination. A dedicated pile-up
“mitigation” strategy is beyond the scope of our analysis, also because it would require a
detailed detector information, but will certainly have to be taken into account in a possible
experimental analysis. However, we expect our results to remain robust against pile-up effects, since our anal-
ysis mostly relies on the identification of leptons and exploits the HEPTopTagger to test the
hadronic activity, with an effective soft-radiation rejection already built-in through a filter-
ing procedure. In a recent publication [29] a thorough discussion has been presented of a
possible search strategy for top partners including an estimation of pile-up effects: although
being affected by pile-up contamination, the results of their analysis are still consistent. JHEP01(2015)088 4
Results The procedure detailed in section 3 has a double benefit, namely largely improving the
S/B ratio on one hand, and on the other hand uniquely determining the 4-momenta of
the reconstructed top and Z boson candidates satisfying the possible kinematics of a top
partner decay. We finally plot the distribution of the invariant mass of the (t-Z) system, which we
expect to peak at the invariant mass of the on-shell top partner for the signal process,
while described by a smoothly descending distribution for the different backgrounds, since
the reconstructed top and Z in the latter events do not originate from an on-shell decay. We show the result in figure 7, where we rescale the different distributions with the
visible cross section of the corresponding processes, times an assumed integrated luminosity
of 300 fb−1. The different contributions are stacked in the plot. In this way, figure 7 shows
a realistic amount of events which could be observed at the LHC with √s = 13 TeV and
300 fb−1 of integrated luminosity. For the signal we fixed MT = 1 TeV and g∗= 0.1. A peak in the bins around MT = 1 TeV, fixing the bin width to 50 GeV, is clearly
visible above the background distribution, with up to 25 total events in the most significant
bin. The result of the analysis is therefore encouraging, and we support the experimental
collaborations to further analyse the discussed channel: clearly, in a real experimental
search the background estimation would be more robust and precise, e.g. via the inclusion
of reconstructed fake leptons. It is very important to estimate the significance of the signal peak above the SM
background, in order to consistently claim the evidence for or the discovery of a top
partner signal. In particular, the hypothesis testing procedure is carried out using the
public BumpHunter code [82]. This code operates on datasets that are binned in some
a-priori fixed set of bins: in our case, the input datasets correspond to the total number
of signal+background and background-only events observed in MT-bins of 50 GeV as in – 17 – Figure 7. Stacked distribution plot of the invariant mass MT of the reconstructed top partner
for different processes. All distributions have been rescaled with the visible cross section of the
corresponding processes, times an integrated luminosity of 300 fb−1. The signal process assumes
MT = 1 TeV and g∗= 0.1. 1We setup the code to look for bumps in up to three consecutive bins, namely the possible mass resolution
is at worst ± 75 GeV around the central value.
2 is at worst ± 75 GeV around the central value.
2In our case, we choose to model the background expectation by a Poisson distribution with the mean
value distributed according to a Gamma distribution. The latter Gamma distribution is defined by fixing
its mean value to the actual background bin value, and variance to the squared background bin error, as
suggested in the BumpHunter manual. A total number of 108 pseudo-experiments is generated accordingly. 4
Results Other possible SM background processes are not shown in the plot since
their contribution turned out to be negligible. JHEP01(2015)088 Figure 7. Stacked distribution plot of the invariant mass MT of the reconstructed top partner
for different processes. All distributions have been rescaled with the visible cross section of the
corresponding processes, times an integrated luminosity of 300 fb−1. The signal process assumes
MT = 1 TeV and g∗= 0.1. Other possible SM background processes are not shown in the plot since
their contribution turned out to be negligible. figure 7. The BumpHunter scans the input-given data using a window of varying width,
and identifies the window with biggest excess compared to the background: the dedicated
test statistic is designed to be sensitive to local excesses of data.1 The same scanning procedure is further applied to pseudo-data sampled from the
expectation of the background input,2 in order to reconstruct the “expected” distribution
of the test statistic. The p-value of the test is calculated, being the probability that the test
statistic will be equal to, or greater than the test statistic obtained by comparing the actual
data to the background hypothesis. In other words, the p-value might be interpreted as a
false-discovery probability. When the distribution of the test statistic is estimated using
pseudo-experiments, as in our case, then the p-value is calculated as a binomial success
probability. An equivalent formulation in terms of Gaussian significance is straightforwardly ob-
tained: it is common to claim that evidence for a new signal beyond the SM background
is observed if the p-value of the peak corresponds to at least 3.0σ of Gaussian significance,
while it is common to claim a discovery if the p-value corresponds to at least 5.0σ of
Gaussian significance. By running the BumpHunter on the datasets summarised in figure 7, the most signifi-
cant peak is observed in the [900, 1050] GeV range, with an equivalent Gaussian significance 1We setup the code to look for bumps in up to three consecutive bins, namely the possible mass resolution
is at worst ± 75 GeV around the central value. 2 – 18 – Figure 8. Parameter space regions of possible evidence (3.0σ) or discovery (5.0σ) of a top partner
signal above the SM background, assuming the described analysis at the LHC with √s = 13 TeV
and 300 fb−1 of integrated luminosity. 4
Results Also shown are bands representing the effect of a possible
further non-statistical 30% uncertainty on the visible cross section of the involved processes. If a
signal peak is observed above the SM background, a possible mass measurement of the top partner
invariant mass MT is possible with a mass resolution of at worst ± 75 GeV around the central value. JHEP01(2015)088 Figure 8. Parameter space regions of possible evidence (3.0σ) or discovery (5.0σ) of a top partner
signal above the SM background, assuming the described analysis at the LHC with √s = 13 TeV
and 300 fb−1 of integrated luminosity. Also shown are bands representing the effect of a possible
further non-statistical 30% uncertainty on the visible cross section of the involved processes. If a
signal peak is observed above the SM background, a possible mass measurement of the top partner
invariant mass MT is possible with a mass resolution of at worst ± 75 GeV around the central value. of 2.6+1.0
−0.9 σ. The uncertainties on the Gaussian significance of the peak are estimated by
applying a 20% uncertainty on both the signal and background event yields, which might
account for up to 30% possible further non-statistical uncertainties which we have not taken
into account. Different hypotheses on the underlying BSM signal would alter the shape of the signal
distribution of figure 7. However, we expect that our analysis, although being optimised
for the signal values MT = 1 TeV and g∗= 0.1, should still display a peak in the MT distri-
bution even for different choices of the free parameters. In particular, a higher statistical
significance of the peak might be achieved for different signal hypotheses. For this reason,
we generate a grid of signal points for MT ∈[850, 1450] GeV in steps of 150 GeV, and for
g∗∈[0.05, 0.5] in steps of 0.05, and for each combination we evaluate the corresponding
significance of the peak, if observed. Our results are displayed in figure 8, where regions of possible evidence (3.0σ) or
discovery (5.0σ) of a top partner signal above the SM background are identified, assuming
a dedicated LHC analysis as discussed in the text. Also shown are bands representing the
effect of a possible total 30% uncertainty as discussed before. 4
Results We observe that a large
fraction of the considered parameter space might be probed using our proposed analysis;
in particular, the top partner mass might be measured via the described BumpHunter
procedure, with a mass resolution in our setup of at worst ± 75 GeV around the central
value. The mass resolution might also be improved in a dedicated experimental setup. – 19 – From figure 8 we see that the signal is within the range of possible evidence for top
partner masses up to roughly 1450 GeV with g∗≲0.5, while being still sensitive to g∗cou-
plings down to 0.05 at lower masses. The g∗→0 limit corresponds to the pair-production
only component, being a QCD process independent on the electroweak coupling: one can
observe that within our hypotheses and analysis setup, the single production component
has to be necessarily non-vanishing to guarantee a possible discovery potential of the sig-
nal, since no discovery reach is obtained for values of g∗≲0.05. Analogously, for fixed top
partner mass, the discovery potential increases with g∗, since the single production cross
section grows as |g∗|2. We can now compare the discovery reach as presented in figure 8 with other existing
studies in literature. In particular, we can first compare with the results presented in [30],
where the “trilepton” decay channel T →t Z →(b ℓν) (ℓ+ ℓ−) has been scrutinised. In
here, the authors considered a more general parameter space allowing mixing of the top
partner with the other first two generations of quarks, namely letting the parameter RL to
be non vanishing: this way, the production cross section of the top partner dramatically
increases due to parton distribution enhancement, and the discovery reach becomes highly
sensitive to RL. The highest significance has been observed for RL ∼1, corresponding to
50% mixing. The RL = 0 case, as in our study, can be considered as the conservative
case in which no flavour-changing coupling is introduced. By comparing the discovery
reach obtained in [30] for RL = 0 and 300 fb−1 of integrated luminosity, the trilepton
and dilepton analyses show very similar results: the trilepton analysis of [30] extends the
reach by 200 −300 GeV, probing possible top partner masses up to roughly 1700 GeV with
g∗≲0.5, while being still sensitive to g∗couplings down to 0.1. 5
Conclusion 5 In this paper we have investigated the search for new vector-like heavy third-generation
quarks, particularly top-like quarks in their decay channel into a top quark and a Z bo-
son. Though this neutral-current decay channel has not been thoroughly investigated yet
compared to the corresponding charged-current process into Wb or the decay into th, we
believe that it is nevertheless worthwhile to look into it: firstly, it offers another indepen-
dent search channel, and secondly the absence of missing transverse energy in the final
state allows for a complete mass determination of the heavy top state. In order to be able
to separate the fully hadronic top mode from the huge SM backgrounds, we applied the
techniques of boosted objects and jet substructure to this channel. JHEP01(2015)088 Such heavy vector-like top partners appear in many different BSM models like models
of (partial) compositeness, Little Higgs models, extra-dimensional models etc. In order to
be as model-independent as possible we exploited a simplified model with only two free
parameters, the heavy top mass and an electroweak coupling constant. We took both single
and pair production of the heavy top quarks into account, where generally single production
is the less phase-space constrained. The main SM backgrounds to these processes, Z +
jets, tZ + jets and t¯tZ + jets have been taken into account using known NLO K-factors. The boost of the leptonically decaying Z boson helps to suppress Drell-Yan backgrounds,
while the signal is discriminated by the fat jet characteristics of the collimated decaying
top quark. To determine the sensitivity of the upcoming run II of LHC to such possible new
states in this channel, we used the HepTopTagger to discriminate fat top quark jets from
SM backgrounds on simulated events that have been merged with parton-shower generated
QCD ISR and FSR jets. Afterwards, the fast detector simulation from Delphes has been
used to assess efficiencies and uncertainties from the cut-flow and the taggings. We briefly
discussed possible pile-up contamination and further non-statistical uncertainties. As a final result we gained the 3σ evidence reach as well as the 5σ discovery potential
of LHC run II in the parameter plane of the two variables heavy top mass and effective
coupling. This shows that the discovery potential reaches up to roughly 1400 GeV for the
heavy top quark mass in regions of a still reliable heavy top quark coupling. 5
Conclusion We encourage the experimental collaborations to look into this channel as a possible
discovery channel as well as a means to get direct access to the mass of the heavy top with
a final uncertainty of 75 GeV or better. 4
Results Our dilepton search is
instead more sensitive to lower values of the g∗coupling, namely down to g∗∼0.05 for
top partner masses of 850 GeV. This is mainly due to the different b-jet cut requirement:
while in the trilepton analysis exactly one b-jet is required to be identified, in our analysis
we allow for the identification of more than one b-jet in the final state, being thus more
efficient in tagging the pair production component of the signal. JHEP01(2015)088 Although not immediate due to the different parameter space definitions, we can also
draw a comparison with other complementary studies for searches at the LHC run II
involving a singlet top partner. In particular, in [26] the authors show that a mass re-
construction is possible within the T →t h decay channel with 100 fb−1 of integrated
luminosity at √s = 14TeV, proposing a search strategy optimised for two top partner
mass points, namely mT = 800, 900 GeV, and assuming BR(T →t h) = 1.0. Furthermore,
in [28] the authors project at √s = 13 TeV and 100 fb−1 of integrated luminosity the ex-
clusion potential of the analysis first presented in [22], tailored for the leptonic T →W b
decay channel with BR(T →W b) = 0.5, obtaining an exclusion reach up to 2.0 TeV for
single production if cWb
L
≳0.4. Analogously, in [27] the authors design a dedicated search
strategy for the leptonic T →W b decay channel, obtaining an expected exclusion reach
for masses up to 1.0 TeV, including both pair and single production, with √s = 14 TeV
and 30 fb−1 of integrated luminosity. Our analysis is thus competitive with the results of
existing literature, and represents a viable and complementary candidate to pursue the
search and mass measurement of a possible singlet top partner. – 20 – Acknowledgments The authors of this paper are grateful for useful discussions with Maikel de Vries, Lorenzo
Basso, Stefan Prestel, Fabian Bach, Diptimoy Ghosh, Piero Ferrarese. MT has been par-
tially supported by the Deutsche Forschungsgemeinschaft within the Collaborative Re-
search Center SFB 676 “Particles, Strings, Early Universe”. – 21 – Open Access. This article is distributed under the terms of the Creative Commons
Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in
any medium, provided the original author(s) and source are credited. References [1] CMS collaboration, Observation of a new boson at a mass of 125 GeV with the CMS
experiment at the LHC, Phys. Lett. B 716 (2012) 30 [arXiv:1207.7235] [INSPIRE]. [1] CMS collaboration, Observation of a new boson at a mass of 125 GeV with the CMS
experiment at the LHC, Phys. Lett. B 716 (2012) 30 [arXiv:1207.7235] [INSPIRE]. [2] ATLAS collaboration, Observation of a new particle in the search for the Standard Model
Higgs boson with the ATLAS detector at the LHC, Phys. Lett. B 716 (2012) 1
[arXiv:1207.7214] [INSPIRE]. JHEP01(2015)088 JHEP01(2015)088 [3] ATLAS collaboration, Search for pair and single production of new heavy quarks that decay
to a Z boson and a third generation quark in pp collisions at √s = 8 TeV with the ATLAS
detector, ATLAS-CONF-2014-036 (2014). [3] ATLAS collaboration, Search for pair and single production of new heavy quarks that decay
to a Z boson and a third generation quark in pp collisions at √s = 8 TeV with the ATLAS
detector, ATLAS-CONF-2014-036 (2014). [4] ATLAS collaboration, Search for pair and single production of new heavy quarks that decay
to a Z boson and a third-generation quark in pp collisions at √s = 8 TeV with the ATLAS
detector, JHEP 11 (2014) 104 [arXiv:1409.5500] [INSPIRE]. [5] ATLAS collaboration, Search for pair production of heavy top-like quarks decaying to a
high-pT W boson and a b quark in the lepton plus jets final state in pp collisions at
√s = 8 TeV with the ATLAS detector, ATLAS-CONF-2013-060 (2013) [INSPIRE]. [6] CMS collaboration, Boosted Top Jet Tagging at CMS, CMS-PAS-JME-13-007 (2014)
[INSPIRE]. [7] CMS collaboration, Inclusive search for a vector-like T quark with charge 2
3 in pp collisions
at √s = 8 TeV, Phys. Lett. B 729 (2014) 149 [arXiv:1311.7667] [INSPIRE]. [8] CMS collaboration, Search for vector-like top quark partners produced in association with
Higgs bosons in the diphoton final state, CMS-PAS-B2G-14-003 (2014) [INSPIRE]. [9] CMS collaboration, Search for top-Higgs resonances in all-hadronic final states using jet
substructure methods, CMS-PAS-B2G-14-002 (2014) [INSPIRE]. [10] CMS collaboration, Search for vector-like b’ pair production with multilepton final states in
pp collisions at √s = 8 TeV, CMS-PAS-B2G-13-003 (2013) [INSPIRE]. [11] R. Contino and G. Servant, Discovering the top partners at the LHC using same-sign
dilepton final states, JHEP 06 (2008) 026 [arXiv:0801.1679] [INSPIRE]. [12] J.A. Aguilar-Saavedra, Identifying top partners at LHC, JHEP 11 (2009) 030
[arXiv:0907.3155] [INSPIRE]. [12] J.A. References Aguilar-Saavedra, Identifying top partners at LHC, JHEP 11 (2009) 030
[arXiv:0907.3155] [INSPIRE]. [13] J. Mrazek and A. Wulzer, A strong sector at the LHC: top partners in same-sign dileptons
Phys. Rev. D 81 (2010) 075006 [arXiv:0909.3977] [INSPIRE]. [13] J. Mrazek and A. Wulzer, A strong sector at the LHC: top partners in same-sign dileptons,
Phys. Rev. D 81 (2010) 075006 [arXiv:0909.3977] [INSPIRE]. [14] S. Gopalakrishna, T. Mandal, S. Mitra and R. Tibrewala, LHC signatures of a vector-like b’,
Phys. Rev. D 84 (2011) 055001 [arXiv:1107.4306] [INSPIRE]. [14] S. Gopalakrishna, T. Mandal, S. Mitra and R. Tibrewala, LHC signatures of a vector-like b’,
Phys. Rev. D 84 (2011) 055001 [arXiv:1107.4306] [INSPIRE]. [15] N. Vignaroli, Early discovery of top partners and test of the Higgs nature, Phys. Rev. D 86
(2012) 075017 [arXiv:1207.0830] [INSPIRE]. [15] N. Vignaroli, Early discovery of top partners and test of the Higgs nature, Phys. Rev. D 86
(2012) 075017 [arXiv:1207.0830] [INSPIRE]. [16] A. De Simone, O. Matsedonskyi, R. Rattazzi and A. Wulzer, A first top partner Hunter’s
guide, JHEP 04 (2013) 004 [arXiv:1211.5663] [INSPIRE]. [16] A. De Simone, O. Matsedonskyi, R. Rattazzi and A. Wulzer, A first top partner Hunter’s
guide, JHEP 04 (2013) 004 [arXiv:1211.5663] [INSPIRE]. – 22 – [17] J. Kearney, A. Pierce and J. Thaler, Top partner probes of extended Higgs sectors, JHEP 08
(2013) 130 [arXiv:1304.4233] [INSPIRE]. [18] S. Gopalakrishna, T. Mandal, S. Mitra and G. Moreau, LHC signatures of warped-space
vectorlike quarks, JHEP 08 (2014) 079 [arXiv:1306.2656] [INSPIRE]. [19] J. Li, D. Liu and J. Shu, Towards the fate of natural composite Higgs model through single t′
search at the 8 TeV LHC, JHEP 11 (2013) 047 [arXiv:1306.5841] [INSPIRE]. [20] A. Azatov, M. Salvarezza, M. Son and M. Spannowsky, Boosting Top Partner Searches in
Composite Higgs Models, Phys. Rev. D 89 (2014) 075001 [arXiv:1308.6601] [INSPIRE]. [21] S. Beauceron, G. Cacciapaglia, A. Deandrea and J.D. Ruiz-´Alvarez, Fully hadronic decays of
a singly produced vectorlike top partner at the LHC, Phys. Rev. D 90 (2014) 115008
[arXiv:1401.5979] [INSPIRE]. JHEP01(2015)088 [22] N.G. Ortiz, J. Ferrando, D. Kar and M. Spannowsky, Reconstructing singly produced top
partners in decays to Wb, Phys. Rev. D 90 (2014) 075009 [arXiv:1403.7490] [INSPIRE]. [23] C. Han, A. Kobakhidze, N. Liu, L. Wu and B. Yang, Constraining top partner and
naturalness at the LHC and TLEP, Nucl. Phys. B 890 (2015) 388 [arXiv:1405.1498]
[INSPIRE]. [24] G. Brooijmans, R. Contino, B. Fuks, F. References Moortgat, P. Richardson et al., Les Houches 2013:
physics at TeV colliders: new physics working group report, arXiv:1405.1617 [INSPIRE]. [25] S. Yang, J. Jiang, Q.-S. Yan and X. Zhao, Hadronic b’ search at the LHC with top and W
taggers, JHEP 09 (2014) 035 [arXiv:1405.2514] [INSPIRE]. [26] M. Endo, K. Hamaguchi, K. Ishikawa and M. Stoll, Reconstruction of vector-like top partner
from fully hadronic final states, Phys. Rev. D 90 (2014) 055027 [arXiv:1405.2677]
[INSPIRE]. [27] B. Gripaios, T. M¨uller, M.A. Parker and D. Sutherland, Search strategies for top partners in
composite Higgs models, JHEP 08 (2014) 171 [arXiv:1406.5957] [INSPIRE]. [28] O. Matsedonskyi, G. Panico and A. Wulzer, On the interpretation of top partners searches,
JHEP 12 (2014) 097 [arXiv:1409.0100] [INSPIRE]. [29] M. Backovi´c, G. Perez, T. Flacke and S.J. Lee, LHC top partner searches beyond the 2 TeV
mass region, arXiv:1409.0409 [INSPIRE]. [30] L. Basso and J. Andrea, Discovery potential for T ′ →tZ in the trilepton channel at the
LHC, arXiv:1411.7587 [INSPIRE]. [31] D.B. Kaplan and H. Georgi, SU(2) × U(1) breaking by vacuum misalignment, Phys. Lett. B
136 (1984) 183 [INSPIRE]. [32] D.B. Kaplan, H. Georgi and S. Dimopoulos, Composite Higgs scalars, Phys. Lett. B 136
(1984) 187 [INSPIRE]. [33] D.B. Kaplan, Flavor at SSC energies: a new mechanism for dynamically generated fermion
masses, Nucl. Phys. B 365 (1991) 259 [INSPIRE]. [34] R. Contino, T. Kramer, M. Son and R. Sundrum, Warped/composite phenomenology
simplified, JHEP 05 (2007) 074 [hep-ph/0612180] [INSPIRE]. [35] K. Agashe, R. Contino and A. Pomarol, The Minimal composite Higgs model, Nucl. Phys. B
719 (2005) 165 [hep-ph/0412089] [INSPIRE]. – 23 – [36] R. Contino, L. Da Rold and A. Pomarol, Light custodians in natural composite Higgs models,
Phys. Rev. D 75 (2007) 055014 [hep-ph/0612048] [INSPIRE]. [37] M.S. Carena, E. Ponton, J. Santiago and C.E.M. Wagner, Electroweak constraints on warped
models with custodial symmetry, Phys. Rev. D 76 (2007) 035006 [hep-ph/0701055]
[INSPIRE]. [38] S.R. Coleman, J. Wess and B. Zumino, Structure of phenomenological Lagrangians. 1., Phys. Rev. 177 (1969) 2239 [INSPIRE]. [39] C.G. Callan Jr., S.R. Coleman, J. Wess and B. Zumino, Structure of phenomenological
Lagrangians. 2., Phys. Rev. 177 (1969) 2247 [INSPIRE]. JHEP01(2015)088 [40] N. Arkani-Hamed, A.G. Cohen, E. Katz and A.E. Nelson, The littlest Higgs, JHEP 07
(2002) 034 [hep-ph/0206021] [INSPIRE]. JHEP01(2015)088 [41] H.-C. Cheng and I. Low, TeV symmetry and the little hierarchy problem, JHEP 09 (2003)
051 [hep-ph/0308199] [INSPIRE]. [42] H.-C. References Cheng and I. Low, Little hierarchy, little Higgses and a little symmetry, JHEP 08
(2004) 061 [hep-ph/0405243] [INSPIRE]. [43] T. Han, H.E. Logan, B. McElrath and L.-T. Wang, Phenomenology of the little Higgs model,
Phys. Rev. D 67 (2003) 095004 [hep-ph/0301040] [INSPIRE]. [44] J. Hubisz and P. Meade, Phenomenology of the littlest Higgs with T-parity, Phys. Rev. D 71
(2005) 035016 [hep-ph/0411264] [INSPIRE]. [45] J. Hubisz, P. Meade, A. Noble and M. Perelstein, Electroweak precision constraints on the
littlest Higgs model with T parity, JHEP 01 (2006) 135 [hep-ph/0506042] [INSPIRE]. [46] C.-R. Chen, K. Tobe and C.-P. Yuan, Higgs boson production and decay in little Higgs
models with T-parity, Phys. Lett. B 640 (2006) 263 [hep-ph/0602211] [INSPIRE]. [47] A. Belyaev, C.-R. Chen, K. Tobe and C.-P. Yuan, Phenomenology of littlest Higgs model with
T −parity: including effects of T −odd fermions, Phys. Rev. D 74 (2006) 115020
[hep-ph/0609179] [INSPIRE]. [48] M. Blanke, A.J. Buras, A. Poschenrieder, S. Recksiegel, C. Tarantino et al., Rare and
CP-violating K and B decays in the littlest Higgs model with T −parity, JHEP 01 (2007) 066
[hep-ph/0610298] [INSPIRE]. [49] C. Cs´aki, J. Hubisz, G.D. Kribs, P. Meade and J. Terning, Big corrections from a little Higgs,
Phys. Rev. D 67 (2003) 115002 [hep-ph/0211124] [INSPIRE]. [50] W. Kilian and J. Reuter, The low-energy structure of little Higgs models, Phys. Rev. D 70
(2004) 015004 [hep-ph/0311095] [INSPIRE]. [51] J. Reuter and M. Tonini, Can the 125 GeV Higgs be the little Higgs?, JHEP 02 (2013) 077
[arXiv:1212.5930] [INSPIRE]. [52] W. Kilian, D. Rainwater and J. Reuter, Pseudo-axions in little Higgs models, Phys. Rev. D
71 (2005) 015008 [hep-ph/0411213] [INSPIRE]. [53] W. Kilian, D. Rainwater and J. Reuter, Distinguishing little-Higgs product and simple group
models at the LHC and ILC, Phys. Rev. D 74 (2006) 095003 [Erratum ibid. D 74 (2006)
099905] [hep-ph/0609119] [INSPIRE]. [54] J. Berger, J. Hubisz and M. Perelstein, A fermionic top partner: naturalness and the LHC,
JHEP 07 (2012) 016 [arXiv:1205.0013] [INSPIRE]. – 24 – [55] M. Asano, S. Matsumoto, N. Okada and Y. Okada, Cosmic positron signature from dark
matter in the littlest Higgs model with T-parity, Phys. Rev. D 75 (2007) 063506
[hep-ph/0602157] [INSPIRE]. [56] J. Reuter, M. Tonini and M. de Vries, Little Higgs model limits from LHC — Input for
Snowmass 2013, arXiv:1307.5010 [INSPIRE]. [57] J. Reuter, M. Tonini and M. References de Vries, Littlest Higgs with T-parity: status and prospects,
JHEP 02 (2014) 053 [arXiv:1310.2918] [INSPIRE]. [58] M. Buchkremer, G. Cacciapaglia, A. Deandrea and L. Panizzi, Model independent framework
for searches of top partners, Nucl. Phys. B 876 (2013) 376 [arXiv:1305.4172] [INSPIRE]. JHEP01(2015)088 [59] J.M. Butterworth, A.R. Davison, M. Rubin and G.P. Salam, Jet substructure as a new Higgs
search channel at the LHC, Phys. Rev. Lett. 100 (2008) 242001 [arXiv:0802.2470]
[INSPIRE]. [60] T. Plehn, M. Spannowsky, M. Takeuchi and D. Zerwas, Stop reconstruction with tagged tops,
JHEP 10 (2010) 078 [arXiv:1006.2833] [INSPIRE]. [61] T. Plehn and M. Spannowsky, Top tagging, J. Phys. G 39 (2012) 083001 [arXiv:1112.4441]
[INSPIRE]. [62] J. Alwall, R. Frederix, S. Frixione, V. Hirschi, F. Maltoni et al., The automated computation
of tree-level and next-to-leading order differential cross sections and their matching to parton
shower simulations, JHEP 07 (2014) 079 [arXiv:1405.0301] [INSPIRE]. [63] T. Sj¨ostrand, S. Mrenna and P.Z. Skands, A Brief Introduction to PYTHIA 8.1, Comput. Phys. Commun. 178 (2008) 852 [arXiv:0710.3820] [INSPIRE]. [64] DELPHES 3 collaboration, J. de Favereau et al., DELPHES 3: a modular framework for
fast simulation of a generic collider experiment, JHEP 02 (2014) 057 [arXiv:1307.6346]
[INSPIRE]. [65] W. Kilian, T. Ohl and J. Reuter, WHIZARD — simulating multi-particle processes at LHC
and ILC, Eur. Phys. J. C 71 (2011) 1742 [arXiv:0708.4233] [INSPIRE]. [66] M. Moretti, T. Ohl and J. Reuter, O’Mega: an optimizing matrix element generator,
hep-ph/0102195 [INSPIRE]. [67] W. Kilian, J. Reuter, S. Schmidt and D. Wiesler, An analytic initial-state parton shower,
JHEP 04 (2012) 013 [arXiv:1112.1039] [INSPIRE]. [68] M. Cacciari, G.P. Salam and G. Soyez, FastJet user manual, Eur. Phys. J. C 72 (2012) 1896
[arXiv:1111.6097] [INSPIRE]. [69] M. Cacciari and G.P. Salam, Dispelling the N 3 myth for the kt jet-finder, Phys. Lett. B 641
(2006) 57 [hep-ph/0512210] [INSPIRE]. [70] N.D. Christensen and C. Duhr, FeynRules — Feynman rules made easy, Comput. Phys. Commun. 180 (2009) 1614 [arXiv:0806.4194] [INSPIRE]. [71] C. Degrande, C. Duhr, B. Fuks, D. Grellscheid, O. Mattelaer et al., UFO — The universal
FeynRules output, Comput. Phys. Commun. 183 (2012) 1201 [arXiv:1108.2040] [INSPIRE]. [72] N.D. Christensen, C. Duhr, B. Fuks, J. Reuter and C. Speckner, Introducing an interface
between WHIZARD and FeynRules, Eur. Phys. J. C 72 (2012) 1990 [arXiv:1010.3251]
[INSPIRE]. – 25 – [73] M. Aliev, H. Lacker, U. Langenfeld, S. Moch, P. [82] G. Choudalakis, On hypothesis testing, trials factor, hypertests and the BumpHunter,
arXiv:1101.0390 [INSPIRE]. References Uwer et al., HATHOR — HAdronic Top
and Heavy quarks crOss section calculatoR, Comput. Phys. Commun. 182 (2011) 1034
[arXiv:1007.1327] [INSPIRE]. [74] P. Kant, O.M. Kind, T. Kintscher, T. Lohse, T. Martini et al., HATHOR for single top-quark
production: updated predictions and uncertainty estimates for single top-quark production in
hadronic collisions, arXiv:1406.4403 [INSPIRE]. [75] S. Catani, F. Krauss, R. Kuhn and B.R. Webber, QCD matrix elements + parton showers,
JHEP 11 (2001) 063 [hep-ph/0109231] [INSPIRE]. [76] L. L¨onnblad, Correcting the color dipole cascade model with fixed order matrix elements,
JHEP 05 (2002) 046 [hep-ph/0112284] [INSPIRE]. JHEP01(2015)088 JHEP01(2015)088 [77] L. L¨onnblad and S. Prestel, Matching tree-level matrix elements with interleaved showers,
JHEP 03 (2012) 019 [arXiv:1109.4829] [INSPIRE]. [78] S. Catani, L. Cieri, G. Ferrera, D. de Florian and M. Grazzini, Vector boson production at
hadron colliders: a fully exclusive QCD calculation at NNLO, Phys. Rev. Lett. 103 (2009)
082001 [arXiv:0903.2120] [INSPIRE]. [79] A. Kardos, Z. Tr´ocs´anyi and C. Papadopoulos, Top quark pair production in association with
a Z-boson at NLO accuracy, Phys. Rev. D 85 (2012) 054015 [arXiv:1111.0610] [INSPIRE]. [80] J. Campbell, R.K. Ellis and R. R¨ontsch, Single top production in association with a Z boson
at the LHC, Phys. Rev. D 87 (2013) 114006 [arXiv:1302.3856] [INSPIRE]. [81] ATLAS collaboration, Search for anomalous production of prompt like-sign lepton pairs at
√s = 7 TeV with the ATLAS detector, JHEP 12 (2012) 007 [arXiv:1210.4538] [INSPIRE]. [82] G. Choudalakis, On hypothesis testing, trials factor, hypertests and the BumpHunter,
arXiv:1101.0390 [INSPIRE]. – 26 –
|
https://openalex.org/W3015737837
|
https://riunet.upv.es/bitstream/10251/166205/1/Iglesas%3bAntonno%3bFern%c3%a1ndez%20-%20Hgher-order%20spectral%20analyss%20of%20stray%20flux%20sgnals%20for%20faults%20detecton....pdf
|
English
| null |
Higher-Order Spectral Analysis of Stray Flux Signals for Faults Detection in Induction Motors
|
Applied mathematics and nonlinear sciences
| 2,020
|
cc-by
| 7,278
|
Abstract This work is a review of current trends in the stray flux signal processing techniques applied to the diagnosis of electrical
machines. Initially, a review of the most commonly used standard methods is performed in the diagnosis of failures in
induction machines and using stray flux; and then specifically it is treated and performed the algorithms based on statistical
analysis using cumulants and polyspectra. In addition, the theoretical foundations of the analyzed algorithms and examples
applications are shown from the practical point of view where the benefits that processing can have using HOSA and its
relationship with stray flux signal analysis, are illustrated. Applied Mathematics and Nonlinear Sciences
https://www.sciendo.com Higher-Order Spectral Analysis of Stray Flux Signals for Faults Detection in Induc-
tion Motors Miguel E. Iglesias Martínez1,2, Jose A. Antonino-Daviu3, Pedro Fernández de Córdoba2, J. Alberto
Conejero2 † 1 Departamento de Telecomunicaciones, Universidad de Pinar del Río, Pinar del Río, Martí 270, CP 20100,
Cuba 1 Departamento de Telecomunicaciones, Universidad de Pinar del Río, Pinar del Río, Martí 270, CP 20100,
Cuba 1 Departamento de Telecomunicaciones, Universidad de Pinar del Río, Pinar del Río, Martí 270, CP 20100,
Cuba 2Instituto Universitario de Matemática Pura y Aplicada, Universitat Politècnica de València, E46022 València,
Spain 2Instituto Universitario de Matemática Pura y Aplicada, Universitat Politècnica de València, E46022 València,
Spain 3Instituto de Tecnología Eléctrica, Universitat Politècnica de València, E46022 València
Spain Communicated by Juan Luis García Guirao
Received September 4th 2019
Accepted September 30th 2019
Available online March 31st 2020 Keywords: Cumulants; Higher-Order Spectra; Stray Flux; Faults Diagnosis.
AMS 2010 codes: 60K30, 60G35. Applied Mathematics and Nonlinear Sciences (aop) 1–14 Applied Mathematics and Nonlinear Sciences (aop) 1–14 †Corresponding author. p
g
Email address: aconejero@upv.es 1 Introduction The monitoring and diagnosis of rotary electric machines have taken great importance in current applications
of industry, aeronautics, and telecommunications, among other branches of science and technology. They have
fostered the development of numerous methods to monitor and diagnose different types of failures in electric †Corresponding author. Email address: aconejero@upv.es Open Access. © 2020 M.E. Iglesias-Martínez et al., published by Sciendo. This work is licensed under the Creative Commons Attribution alone 4.0 License. ISSN 2444-8656
doi:10.2478/AM doi:10.2478/AMNS.2020.1.00032 doi:10.2478/AMNS.2020.1.00032 M.E. Iglesias-Martínez et al. Applied Mathematics and Nonlinear Sciences (aop) 1–14 2 machines. These techniques have been designed to increase machines efficiency, safety, and performance, from
the reliability and energy point of view [17,32]. In principle, each one of these techniques are based on processing different signals that can be captured
by sensors that measure parameters such as mechanical vibrations, stator current, acoustic signal, and stray
flux. They let us monitor the condition of electric machines and detect numerous failures such as design and
manufacture defects, improper ambient conditions, overload and over-speed, fatigue, stator insulation failure,
bearing fault, broken rotor bar/end-ring detection, and air gap eccentricity [17]: One of the most commonly used techniques is vibration analysis [10, 12, 58] and motor-current analysis or
motor current signature analysis (MCSA) [35, 64, 65]. These techniques are based on the spectrum analysis
using the Fourier transform for the detection of specific faults since the frequency spectrum shows numerous
harmonics including the fundamental and the faults adjacent frequencies, that differ between faulty and healthy
motors, because different electrical and mechanical faults generate different signatures [11,13,16]. On the other hand, there are other techniques based on the acoustic signal processing that emanates from the
rotor noise [1,12,19]. Their goal is to identify and extract features of signals that correspond to faults [18]. For
this purpose, techniques like the Fourier transform has been used to analyze the noise [43]. However, it presents
the fundamental disadvantage hat the power spectrum is not immune to noise. Other techniques applied to this
identification are based on high-resolution spectral analysis, wavelet transforms [2,36,55], and empirical modes
decomposition [12]. Relating to artificial intelligence-based methods for diagnosing failures [38], there are several works for
failure classifications and pattern recognition. These works are differentiated in dissimilar methods of artificial
intelligence such as artificial neural networks [5, 26, 41, 48, 49, 56] genetic algorithms [54, 69], support vector
machines [4,21,39,57,59,68], Bayesian classifiers [42,44,70]. In general, these methods are based on the initial information available to the system, in addition to learning
the process that can be supervised or unsupervised, and extracting characteristics based on logical knowledge,
using the stator current, vibration signals and sounds of the motor. doi:10.2478/AMNS.2020.1.00032 Furthermore, failure detection methods based on higher-order statistical analysis have been applied to vi-
bration signals, by considering the information provided by cumulants and moments of orders greater than or
equal to two, as well as the spatial information that extracted from the analysis of higher-order spectra such
as the bispectrum [29, 30, 33, 34, 50, 63, 66]. In addition to statistical estimators such as variance, kurtosis and
skewness, derived from the cumulants of second, third, and fourth orders respectively are performed. At present, the treatment of failures in electric induction machines has taken a high boom in relation to
the analysis of the stray flux signals for the detection of failures, see the recent review of Jiang et al. [32]. However, it is not considered based on the use of statistical analysis of cumulants nor High-Order Spectra
Analysis (HOSA). Since HOSA-based techniques are immune to Gaussian probabilistic density function noise,
the spectral properties of the signal are preserved. Therefore, HOSA-based analysis of stray flux signals can be
potentially used for fault detection. We focus on providing an update of the statistical analysis techniques based on cumulants and higher-order
spectra applied to the diagnosis of failures using stray flux signals. The work is organized as follows: In Section
II, we review existing fault diagnosis methods from stray flux signals. In Section III, we show the theoretical
foundations of a statistical analysis based on high-order cumulants and polyspectra. The use of HOSA on stray
flux signals for fault detection is shown in Section IV. Finally, we provide some conclusions and prospective
lines for future work in this line. 2 Faults Detection Based on Stray Flux Analysis The magnetic flux is measured by circular search coils and hall sensors, that are concentric with the shaft
inside the machine. They generate a voltage proportional to the magnetic field generated by the flux. In addition
to these sensors, other types of sensors based on optical fiber and radiofrequency have been already used [17,20]. HOSA of Stray Flux Signals for Faults Detection in Induction Motors 3 Recently, a smart sensor has been proposed to detect winding insulation failures based on reconfigurable FPGA
technology and using artificial neural networks [67]. 2.2
Bearing Fault Detection It is estimated that approximately 35-55 percent of all cases of failures in electrical machines are Bearing
Fault Detection, so this type of failure is investigated very frequently in the monitoring and diagnosis of electrical
machines. Approximately 40 percent of these are caused by the inappropriate use of lubricants. Some indicators
that reveal that the nature of this type of failure lies in the increase in temperature and mechanical vibrations and
the increase in the acoustic noise level generated by the machine [14,24,31]. Some experimental measurements
were carried out using a current probe and by means of different flux probes, positioned in different positions
[14, 23]. The comparison is conducted to find the main advantages which are the simplicity and the flexibility
of the custom flux probe with its amplification and filtering stage depend on the relative position used for the
experiments [47]. 2.1
Stator Insulation Monitoring And Failure Detection Stray flux has been proved to detect the stator winding insulation failure. The main difference for fault
detection respect to the use of flow signals consists of the type of sensor to be used and the position where the
measurement is taken. One way to detect this type of failure is by applying a load and not load test, that provides
significant similarities, even if the stator current gives interesting diagnostic information only when the motor is
loaded. Considering power supply harmonics, it is possible to easily detect the stator winding faults in the low-
frequency range of the flux spectrum. One of the most used methods to detect this type of failure is the time-
frequency analysis based on the signal spectrogram since this analysis generates important amplitude compo-
nents in specific harmonics [32]. 2.4
Broken Bars Detection Induction motors are widely extended in industry, and among the defects which may appear, broken rotor
bars represent 10 percent to 20 percent of the whole faults. This kind of failure does not cause an immediate
breakdown, but it deteriorates the machine operation, decreasing its performance [7, 46]. For the detection of
this type of failure, different algorithms based on the stray flux signal time-frequency analysis of the Fourier and
wavelets transforms have been used. Each technique presents its particular advantages and drawbacks. When a bar breakage occurs, a backward rotating magnetic field is generated due to the open-circuited bar. This creates an asymmetry in the rotor cage that is clearly reflected in the motors harmonic content [8,15,45] When a bar breakage occurs, a backward rotating magnetic field is generated due to the open-circuited bar. The lower sideband harmonic leads to a torque (and speed) oscillation, which provokes the appearance of
s, another harmonic in the stator current spectrum: the upper (or right) sideband harmonic given by 1 + 2sf. Moreover, the frequency modulation on the rotational frequency f, provoked by the speed oscillation, also leads
to sideband harmonics in the vibration (and, accordingly, in the noise) spectrum: fbb = frr ±2ksf
(2) (2) fbb = frr ±2ksf 2.3
Air Gap Eccentricity Detection Motor eccentricity failures are permissible up to 10 percent, and they do not have a significant influence on
the characteristics of the motor and its useful life. However, a high level of eccentricity can cause a magnetic im-
balance and therefore an increase in noise and vibrations [71]. Experimental results have revealed the potential
of a simple search coil for the detection and the distinction of the accurate eccentricity nature even in the pres-
ence of similar mechanical faults [53]. Dynamic eccentricity produces low-frequency air gap flux components. However, they can be observed in stator current only under mixed eccentricity. Moreover, detection of dynamic
eccentricity in stator current around the principal slot harmonic (PSH) is only useful for some combination of
pole pairs and rotor slots [53,61,62]. Fig. 1 Examples of Eccentricity: a) Without eccentricity (b) Static eccentricity (c) Dynamic eccentricity (d) Mixed
eccentricity. [47]. Fig. 1 Examples of Eccentricity: a) Without eccentricity (b) Static eccentricity (c) Dynamic eccentricity (d) Mixed
eccentricity. [47]. Fig. 1 Examples of Eccentricity: a) Without eccentricity (b) Static eccentricity (c) Dynamic eccentricity (d) Mixed
eccentricity. [47]. M.E. Iglesias-Martínez et al. Applied Mathematics and Nonlinear Sciences (aop) 1–14 4 Under mixed eccentricity conditions, the stator currents contain the following frequencies [47]: fecc = f ±k(1−s)⧸pf,
(1) (1) where s is the machine slip. Since the frequencies related to the eccentricity and to the load torque overlap on
the current sidebands, the frequencies provided by (1) are no longer enough for the diagnosis. 3 Higher-Order Statistical Analysis: Theoretical Foundations Higher-order spectral analysis, also known as polyspectra, is defined in terms of higher-order statistics (cu-
mulants, in particular). Among the specific cases of the higher-order spectra, we find the third-order spectrum,
also called bispectrum or Fourier Transform of the third-order temporal cumulant, and the trispectrum or Fourier
Transform of the fourth-order temporal cumulant Figure 2 illustrates the classification of the higher-order spec-
tra of a signal. Although the higher-order statistical characteristics and the spectrum of a signal can be defined in
terms of moments and cumulants, moments and their spectra can be very useful in the analysis of deterministic
signals (transient and periodic), while cumulants and their spectra are of great importance in the analysis of
stochastic signals [40]. There are several motivations behind the use of higher-order spectra in signal processing, which can be used
to: (1) eliminate Gaussian additive colored noise from an unknown power spectrum; (2) extract information due
to process deviations whose probabilistic distribution function is Gaussian, and (3) detect and characterize the
nonlinear properties in the signals, as well as identify nonlinear systems. The first motivation is based on the property that for stationary signals with Gaussian probabilistic distri-
bution function, higher-order cumulants are equal to zero. If a non-Gaussian signal is received together with
additive Gaussian noise, a calculation of the higher-order cumulant of the signal sample plus noise will elim-
inate the noise. Therefore, in these signal processing environments, there will be certain advantages for the
detection and/or estimation of signal parameters through the cumulant of the observed data [40]. 3.1
Higher-Order Statistics. Definition and Properties In this section, the definitions, properties, and the way of calculating higher-order statistics are introduced. Let X = {X(k)}, k = 0,±1,±2,... be a stationary random vector and its higher order moments exist, then: mX
n (τ1,τ2,...,τn−1) = E{X(k)X(k +τ1)···X(k +τn−1)} mX
n (τ1,τ2,...,τn−1) = E{X(k)X(k +τ1)···X(k +τn−1)}
(3) (3) HOSA of Stray Flux Signals for Faults Detection in Induction Motors
5 HOSA of Stray Flux Signals for Faults Detection in Induction Motors 5 where E denotes the expected value operator [6,37,40], represents the n-th order moment of X, which depends
only on the different temporary displacements τ1,τ2,...,τn−1, with τi = 0,±1,.... It can be seen that the second
order moment mX
2 (τ1) is the autocorrelation function of X, likewise mX
3 (τ1) and mX
4 (τ1) represent the third
and fourth order moments, respectively. The cumulants are similar to the moments, the difference is that the
moments of a random process are derived from the characteristic function of the random variable, while the
cumulant generating function is defined as the logarithm of the characteristic function of the random variable. The n-th order cumulant of X can be written as see [37]: The n-th order cumulant of X can be written as, see [37]: cX
n (τ1,...,τn−1) = mX
n (τ1,...,τn−1)−mG
n (τ1,...,τn−1),
n = 3,4,
(4) (4) where mG
n (τ1,τ2,...,τn−1 is the n-order moment of a process with equivalent Gaussian distribution. with the
same average value and autocorrelation function as X, the stationary random vector. From (4) it is evident that
for a process following a Gaussian distribution, the cumulants of order greater or equal than 2 are null, since
mX
n (τ1,...,τn−1) and mG
n (τ1,...,τn−1) are null, too [25] Although fourth-order cumulants imply a considerable increase in calculation complexity, they are especially
necessary when third-order cumulants are canceled in the case of symmetrically distributed processes, such
as uniform distributed processes from [−a,a], with a ∈R, such as Laplace and Gaussian processes. Third-
order cumulants are not canceled for processes whose probabilistic density function is not symmetric, such as
exponential or Rayleigh processes, but can take extremely small values compared to the values presented by
their fourth-order cumulants [60]. Fig. 2 Higher-Order Spectral classification. Here, Fk(·) denote the k-dimensional Fourier Transform, see [40]. g. 2 Higher-Order Spectral classification. Here, Fk(·) denote the k-dimensional Fourier Transform, see [40 3.2
Higher-Order Spectrum The n-th order spectrum of a stationary random vector X = {X(k)}, k = 0,±1,±2,... is defined as the
multidimensional Fourier Transform Fk(·) of order n−1 on the higher order statistical characteristics (moments
and cumulants). The spectrum of the n-moment is defined as [25,60]: MX
n (ω1,...,ωn−1) = Fn[mX
n (τ1,...,τn−1)],
(5) (5) (5) and, similarly, the spectrum of the n−cumulant is defined as CX
n (ω1,...,ωn−1) = Fn[mcX
n (τ1,...,τn−1)],
(6) (6) Note that the spectrum of the n-th order cumulant is also periodic with period 2π, that is: CX
n (ω1,...,ωn−1) = CX
n (ω1 +2π,...,ωn−1 +2π),
(7) (7) CX
n (ω1,...,ωn−1) = CX
n (ω1 +2π,...,ωn−1 +2π), M.E. Iglesias-Martínez et al. Applied Mathematics and Nonlinear Sciences (aop) 1–14 6 CX
n (ω1,...,ωn−1) =
1
(2π)n−1
∞
∑
τ1=−∞
···
∞
∑
τn−1=−∞
cX
n (τ1,...,τn−1)ej(ω1τ1+...+ωn−1τn−1) (8) In particular, for n = 2 in (8), we have the power spectrum In particular, for n = 2 in (8), we have the power spectrum In particular, for n = 2 in (8), we have the power spectrum In particular, for n = 2 in (8), we have the power spectrum CX
2 (ω) = 1
2π
∞
∑
τ=−∞
cX
2 (τ)e−jωτ,
(9) (9) where |ω| ≤π and cX
2 (τ) represents the process covariance sequence, see [25,60]. For n = 3 in (8), we have the bispectrum where |ω| ≤π and cX
2 (τ) represents the process covariance sequence, see [25,60]. For n = 3 in (8), we have the bispectrum CX
3 (ω1,ω2) =
1
(2π)2
∞
∑
τ1=−∞
∞
∑
τ”=−∞
cX
3 (τ1,τ2)e−j(ω1τ1+ω2τ2),
(10) (10) where |ω1| ≤π,|ω2| ≤π, and |ω1 +ω2| ≤π and cX
3 (τ) represents the sequence of third order cumulants of X(k). The expression of the cumulant complies with the following symmetric relationships [60]: where |ω1| ≤π,|ω2| ≤π, and |ω1 +ω2| ≤π and cX
3 (τ) represents the sequence of third order cumulants of X(k). 3.2
Higher-Order Spectrum The expression of the cumulant complies with the following symmetric relationships [60]: cX
3 (τ1,τ2) = cX
3 (τ2,τ1) = cX
3 (−τ2,τ1 −τ2) = cX
3 (τ2 −τ1,−τ1)
(11)
= cX
3 (τ1 −τ2,−τ2) = cX
3 (−τ1,τ2 −τ1) = cX
3 (τ1,τ2)
(12) (11)
(12) (12) From these relationships, we can get a division of the plane τ1τ2 in six regions and, consequently, upon
knowing the third-order cumulant in any of these six regions (see Figure 3), we can reconstruct the complete
sequence corresponding to the third-order cumulants. Note that each one of these regions contains its border. Thus, for example, sector I is an infinite region characterized by 0 eτ2 ≤τ1. For non-stationary processes, these
six regions of symmetry disappear. From these relationships and the definition of the spectrum of third-order
cumulants, the following relationships in the two-dimensional frequency domain can be obtained [6,25,37] CX
3 (ω1,ω2) = CX
3 (ω2,ω1) = CX
3 (−ω2,−ω1) = CX
3 (−ω1 −ω2,ω2)
(13)
= CX
3 (ω1,−ω1 −ω2) = CX
3 (−ω1 −ω2,ω1) = CX
3 (ω2,ω1 −ω2)
(14) (13)
(14) (13)
(14) (14) Figure 3(b) shows the 12 symmetry regions of the bispectrum when real stochastic processes are considered
and, similar to the temporal domain, the knowledge of the bispectrum in the triangular region It is enough
for a total reconstruction of the bispectrum. Note that, in the frequency domain, the symmetry regions have
a finite area and in general, the bispectrum takes complex values and, consequently, the phase information is
preserved [60]. HOSA of Stray Flux Signals for Faults Detection in Induction Motors 7 Fig. 3 Symmetry regions for (a) the third-order cumulant and for (b) the bispectrum. Fig. 3 Symmetry regions for (a) the third-order cumulant and for (b) the bispectrum. n = 4, we get the trispectrum In the case n = 4, we get the trispectrum In the case n = 4, we get the trispectrum CX
4 (ω1,ω2,ω3) =
1
(2π)3
∞
∑
τ1=−∞
∞
∑
τ2=−∞
∞
∑
τ3=−∞
cX
4 (τ1,τ2,τ3)e−j(ω1τ1+ω2τ2+ω3+tau3),
(15) (15) where |ω1| ≤π,|ω2| ≤π,|ω3| ≤π, and |ω1 + ω2 + ω3| ≤π, where cx
4(τ1,τ2,τ3) represents the sequence of
fourth-order cumulants. By combining the definition of the trispectrum and the fourth-order cumulants, 96
regions of symmetry appear associated with a real process. 3.3
Examples of calculation of the Higher-Order Spectra To illustrate in more detail the calculation of the higher-order spectra, we show several examples with peri-
odic signals. 3.2
Higher-Order Spectrum From the spectra of higher-order cumulants, the
expressions of their respective cumulants in the temporal domain can be retrieved, by applying the n-order
inverse Fourier transform [60]. 3.3.1
Cosine signal First, let us consider the cosine signal X = Ak cos(2π fk +ϑk)
(16) (16) X = Ak cos(2π fk +ϑk) X = Ak cos(2π fk +ϑk) with amplitude Ak = 1, frequency fk = 50Hz, and a phase ϑk = 0, discretely generated from a sampling frequency
of fs = 1000Hz and a duration of 1024 samples. Then the bispectrum for a 1024 sample data window is
equivalent to discretely performing the Fourier transform of the third order cumulant of the signal. In figures 4 (a) and (b), respectively shows the cosine signal and its frequency spectrum using the one-
dimensional Fourier Transform (FT). Likewise, as a comparison mode, the bispectrum of the 50 Hz cosine
signal (0.05 normalized to 1) it is shown in Figure 5, to illustrate that the fundamental frequency of the signal
prevails; and also showing other frequency components that by means of the one-dimensional spectrum using
Fourier, they do not appear, which gives the bispectrum a higher resolution from the spectral point of view,
which can be useful for dissimilar applications to find linear combinations or not, of existing relations between
frequencies, for the development of identifying spectral patterns. M.E. Iglesias-Martínez et al. Applied Mathematics and Nonlinear Sciences (aop) 1–14 8 Fig. 4 (a) A cosine signal of 50Hz (0.05 normalized frequency) and (b) its spectrum Fig. 4 (a) A cosine signal of 50Hz (0.05 normalized frequency) and (b) its spectrum Apart from the fundamental frequency component 0.05 (50Hz) normalized to 1, there are other components
as results of linear combinations of the fundamental frequency (16), since the calculation of bispectrum results
in a two-dimensional frequency and a phase matrix, see Figure 5. Fig. 5 Contour plot of the bispectrum of the 50 Hz (0.05) cosine signal. Fig. 5 Contour plot of the bispectrum of the 50 Hz (0.05) cosine signal. On the other hand, although less used, the phase spectrum of the cosine signal of (16) is also shown. The
phase spectrum contains an arrangement with the amplitude in degrees of the phase of the signal, that is taken
as ϑk = π/4 in (16). Its corresponding phase spectrum is shown below in Figure 6. We also show the phase
bispectrum, see Figure 7, where the linear phase of the cosine signal is resalted in the bispectrum phase matrix. 3.3.1
Cosine signal The bispectrum preserves the phase information of every spectral component, that is the phase of the original
signaland it can be otained from the original signal as: On the other hand, although less used, the phase spectrum of the cosine signal of (16) is also shown. The
phase spectrum contains an arrangement with the amplitude in degrees of the phase of the signal, that is taken
as ϑk = π/4 in (16). Its corresponding phase spectrum is shown below in Figure 6. We also show the phase
bispectrum, see Figure 7, where the linear phase of the cosine signal is resalted in the bispectrum phase matrix. The bispectrum preserves the phase information of every spectral component, that is the phase of the original
signaland it can be otained from the original signal as: ϑCX
3 (ω1,ω2) = ϑX(ω1)+ϑX(ω2)+ϑX(ω1 +ω2)
(17) (17) where ϑCX
3 (ω1,ω2) represents the phases matrix of every spectral component. This relation also permits to HOSA of Stray Flux Signals for Faults Detection in Induction Motors 9 retrieve the original phase of the signal. retrieve the original phase of the signal. retrieve the original phase of the signal. Fig. 6 A phase spectrum of a cosine signal of 50Hz (0.05 normalized frequency) Fig. 6 A phase spectrum of a cosine signal of 50Hz (0.05 normalized frequency) Fig. 7 Contour plot of the phase bispectrum of a cosine signal of 50Hz (0.05 normalized frequency) Fig. 7 Contour plot of the phase bispectrum of a cosine signal of 50Hz (0.05 normalized frequency) 3.3.2
Harmonic signal Secondly, we have also experimented by calculating the bispectrum of a harmonic signal of the form: Secondly, we have also experimented by calculating the bispectrum of a harmonic signal of the (18) x(t) = Ak cos(2π fk +ϑk)+2Ak cos(2π ·3fk +ϑk)
(18) In Figures 8 (a) and (b), we show the harmonic signal in time and its frequency spectrum using the one-
dimensional Fourier Transform (FT). In Figure 9, the bispectrum of the harmonic signal is shown. We notice that
the calculation of the bispectrum preserves the fundamental frequencies of each signal in the sum of harmonics,
analogous to the calculation of the one-dimensional FT. We also observe that since the bispectrum is absolutely
summable, multiple frequency components appear as a result of the linear combinations of the bispectrum of M.E. Iglesias-Martínez et al. Applied Mathematics and Nonlinear Sciences (aop) 1–14 10 both cosine signals individually. Fig. 8 Ilustration of : a) Harmonic Signal b) Harmonic Signal Spectrum Fig. 8 Ilustration of : a) Harmonic Signal b) Harmonic Signal Spectrum Fig. 9 Contour Plot of: a) Bispectrum of the Harmonic Signal described in (14) and b) an expanded version of it. Fig. 9 Contour Plot of: a) Bispectrum of the Harmonic Signal described in (14) and b) an expanded version of it. We also show the phase bispectrum of the harmonic signal in Figure 10. It is more complex than th
one of the cosine signal because the bispectrum is absolutely additive, and the phase of the 50Hz and 150H
components are totally mixed. 4 Using second and higher-order statistics with stray flux signals for faults detection Although the analysis based on higher-order spectra in relation to the processing using the classical analysis
based on the power spectrum can be advantageous, and the use of the stray flux signals is a non-invasive method,
few works are linking HOSA (Higher-Order Statistic Analysis) and stray flux signals. This may be because
computational complexity increases when using higher-order statistics in comparison to second-order statistics 11 11 HOSA of Stray Flux Signals for Faults Detection in Induction Motors Fig. 10 Contour plot of the phase bispectrum of a harmonic signal described in (14). Fig. 10 Contour plot of the phase bispectrum of a harmonic signal described in (14). based on the Fourier one-dimensional transform. Most of the works based on the use of HOSA for diagnosing
electric machines are based on the processing of vibration signals [3,9,22,51,52]. based on the Fourier one-dimensional transform. Most of the works based on the use of HOSA for diagnosing
electric machines are based on the processing of vibration signals [3,9,22,51,52]. However, we have recently exposed the advantages of HOSA of stray flux signals [27], where an algorithm
for the detection of the healthy-damaged state condition is proposed using temporary indicators in the frequency
domain based on the bispectrum. Likewise, in [28], a second-order statistical analysis based on the autocorrela-
tion function is linked with stray flux signals for the detection of non-adjacent bar breaks. 5 Conclusions This work has shown a review of the techniques of processing and diagnosing of failures in electric induction
machines. In particular, we have reported how to use them with flux signals. The theoretical foundations and
with practical examples of the High-order statistical analysis (HOSA) and its potential for detecting failures in
electrical machines have also been shown. On the other hand, validated results are also shown in references,
of their use, using stray flux signals, which demonstrates that the linking of high-order statistical analysis tech-
niques with the detection of failures in electric machines can be a very useful tool. Acknowledgements This work has been supported by Generalitat Valenciana, Conselleria d’Educació, Cultura i Esport in
the framework of the “Programa para la promoción de la investigación científica, el desarrollo tecnológico
y la innovación en la Comunitat Valenciana”, Subvenciones para grupos de investigación consolidables (ref:
AICO/2019/224). J. Alberto Conejero is also partially supported by MEC Project MTM2016-75963-P. [1] H. Akçay and E. Germen. Subspace-based identification of acoustic noise spectra in induction motors. IEEE Transac-
tions on Energy Conversion, 30(1):32–40, 2015. y
,
( )
,
[3] N. Arthur and J. Penman. Induction machine condition monitoring with higher order spectra. IEEE Transactions on
Industrial Electronics, 47(5):1031–1041, 2000. gy
[2] J. Antonino-Daviu, M. Riera-Guasp, J. Roger-Folch, F. Martínez-Giménez, and A. Peris. Application and optimization
of the discrete wavelet transform for the detection of broken rotor bars in induction machines. Applied and Computa-
tional Harmonic Analysis, 21(2):268–279, 2006. [1] H. Akçay and E. Germen. Subspace-based identification of acoustic noise spectra in induction motors. IEEE Transac-
tions on Energy Conversion, 30(1):32–40, 2015.
[2] J. Antonino-Daviu, M. Riera-Guasp, J. Roger-Folch, F. Martínez-Giménez, and A. Peris. Application and optimization
of the discrete wavelet transform for the detection of broken rotor bars in induction machines. Applied and Computa-
tional Harmonic Analysis, 21(2):268–279, 2006.
[3] N. Arthur and J. Penman. Induction machine condition monitoring with higher order spectra. IEEE Transactions on
Industrial Electronics, 47(5):1031–1041, 2000. References Fault diagnosis of induction motors using motor current signatu
In Advanced Condition Monitoring and Fault Diagnosis of Electric Machines, pages 1–37. IGI G [17] T. Ghanbari and A. Farjah. A magnetic leakage flux-based approach for fault diagnosis in elect
Sensors Journal, 14(9):2981–2988, 2014. and A. Farjah. A magnetic leakage flux-based approach for fault diagnosis in electrical machines. IEEE
rnal, 14(9):2981–2988, 2014. [18] A. Glowacz. Acoustic based fault diagnosis of three-phase induction motor. Applied Acoustics, 137:82–89, 2018. [19] A Glowacz W Glowacz Z Glowacz and J Kozik Early fault diagnosis of bearing and stator faults of the single phase g
p
pp
[19] A. Glowacz, W. Glowacz, Z. Glowacz, and J. Kozik. Early fault diagnosis of bearing and stator faults o
induction motor using acoustic signals. Measurement, 113:1–9, 2018. , W. Glowacz, Z. Glowacz, and J. Kozik. Early fault diagnosis of bearing and stator faults of the single-phas
motor using acoustic signals. Measurement, 113:1–9, 2018. g
g
[20] T. Goktas, M. Zafarani, K. W. Lee, B. Akin, and T. Sculley. Comprehensive analysis of magnet defect fault monitoring
through leakage flux. IEEE Transactions on Magnetics, 53(4):1–10, 2016. g
g
g
[21] K. C. Gryllias and I. A. Antoniadis. A support vector machine approach based on physical model training for rolling ele-
ment bearing fault detection in industrial environments. Engineering Applications of Artificial Intelligence, 25(2):326–
344, 2012. ,
[22] F. Gu, Y. Shao, N. Hu, A. Naid, and A. Ball. Electrical motor current signal analysis using a modified bispectrum
for fault diagnosis of downstream mechanical equipment. Mechanical Systems and Signal Processing, 25(1):360–372,
2011. [23] C. Harli¸sca, L. Szabó, L. Frosini, and A. Albini. Diagnosis of rolling bearings faults in electric machines through
stray magnetic flux monitoring. In 2013 8TH International Symposium on Advanced Topics in Electrical Engineering
(Atee), pages 1–6. IEEE, 2013. [24] R. Hoppler and R. A. Errath. Motor bearings, not must a piece of metal. In 2007 IEEE Cement Industry Technical
Conference Record, pages 214–233. IEEE, 2007. [25] R. M. Howard. Principles of random signal analysis and low noise design: The power spectral den
cations. John Wiley & Sons, 2004. ard. Principles of random signal analysis and low noise design: The power spectral density and its appli-
hn Wiley & Sons, 2004. y
[26] J.-N. Hwang and Y. H. Hu. Handbook of neural network signal processing. CRC press, 2001. [26] J.-N. Hwang and Y. H. Hu. References 12 M.E. Iglesias-Martínez et al. Applied Mathematics and Nonlinear Sciences (aop) 1–14 [4] T. P. Banerjee and S. Das. Multi-sensor data fusion using support vector machine for motor fault detection. Information
Sciences, 217:96–107, 2012. [5] G. Bin, J. Gao, X. Li, and B. Dhillon. Early fault diagnosis of rotating machinery based on wavelet packets—empirical
mode decomposition feature extraction and neural network. Mechanical Systems and Signal Processing, 27:696–711,
2012. hash, E. J. Powers, and A. M. Zoubir. Higher-order statistical signal processing. Longman Cheshire, 1995 [7] A. Ceban, R. Pusca, and R. Romary. Eccentricity and broken rotor bars faults-effects on the external axial field. In The
XIX International Conference on Electrical Machines-ICEM 2010, pages 1–6. IEEE, 2010. [8] I. Chernyavska and O. Vítek. Analysis of broken rotor bar fault in a squirrel-cage induction motor by means of stator
current and stray flux measurement. In 2016 IEEE International Power Electronics and Motion Control Conference
(PEMC), pages 532–537. IEEE, 2016. (
) p g
[9] T. Chow and G. Fei. Three phase induction machines asymmetrical faults identification using bispectrum. IEEE
Transactions on Energy Conversion, 10(4):688–693, 1995. [10] X. Dai and Z. Gao. From model, signal to knowledge: A data-driven perspective of fault detection and diagnosis. IEEE
Transactions on Industrial Informatics, 9(4):2226–2238, 2013. [11] J. de Jesus Rangel-Magdaleno, H. Peregrina-Barreto, J. M. Ramirez-Cortes, P. Gomez-Gil, and R. Morales-Caporal. Fpga-based broken bars detection on induction motors under different load using motor current signature analysis and
mathematical morphology. IEEE Transactions on Instrumentation and Measurement, 63(5):1032–1040, 2013. p
gy
,
( )
,
[12] P. A. Delgado-Arredondo, D. Morinigo-Sotelo, R. A. Osornio-Rios, J. G. Avina-Cervantes, H. Rostro-Gonzalez, and
R. de Jesus Romero-Troncoso. Methodology for fault detection in induction motors via sound and vibration signals. Mechanical Systems and Signal Processing, 83:568–589, 2017. y
g
g
[13] M. Drif and A. J. M. Cardoso. Stator fault diagnostics in squirrel cage three-phase induction motor drives using the
instantaneous active and reactive power signature analyses. IEEE Transactions on Industrial Informatics, 10(2):1348–
1360, 2014. [14] L. Frosini, C. Harli¸sca, and L. Szabó. Induction machine bearing fault detection by means of statistical processing of
the stray flux measurement. IEEE Transactions on Industrial Electronics, 62(3):1846–1854, 2014. [15] Z. Gao, C. Cecati, and S. X. Ding. A survey of fault diagnosis and fault-tolerant techniques—part i: Fault diagnosis
with model-based and signal-based approaches. IEEE Transactions on Industrial Electronics, 62(6):3757–3767, 2015. [16] M. Geethanjali and H. Ramadoss. References Mechanical Systems and Signal Processing, 108:33–47, 2018. y
g
g
[39] Z. Liu, H. Cao, X. Chen, Z. He, and Z. Shen. Multi-fault classification based on wavelet svm with pso algorithm to
analyze vibration signals from rolling element bearings. Neurocomputing, 99:399–410, 2013. y
g
g
g
p
g
[40] J. M. Mendel. Tutorial on higher-order statistics (spectra) in signal processing and system theory: T
and some applications. Proceedings of the IEEE, 79(3):278–305, 1991. pp
g
f
( )
[41] M. Mrugalski, M. Witczak, and J. Korbicz. Confidence estimation of the multi-layer perceptron and its application in
fault detection systems. Engineering Applications of Artificial Intelligence, 21(6):895–906, 2008. y
g
g
pp
f
fi
g
( )
[42] V. Muralidharan and V. Sugumaran. A comparative study of naïve bayes classifier and bayes net classifier for fault
diagnosis of monoblock centrifugal pump using wavelet analysis. Applied Soft Computing, 12(8):2023–2029, 2012. [43] Y. Ono, Y. Onishi, T. Koshinaka, S. Takata, and O. Hoshuyama. Anomaly detection of motors with feature emphasis
using only normal sounds. In Acoustics, Speech and Signal Processing (ICASSP), 2013 IEEE International Conference
on, pages 2800–2804. IEEE, 2013. , p g
,
[44] R. H. C. Palácios, I. N. da Silva, A. Goedtel, and W. F. Godoy. A comprehensive evaluation of intelligent classifiers for
fault identification in three-phase induction motors. Electric Power Systems Research, 127:249–258, 2015. [45] P. Panagiotou, I. Arvanitakis, N. Lophitis, J. A. Antonino-Daviu, and K. N. Gyftakis. Analysis of stray flux spectral
components in induction machines under rotor bar breakages at various locations. In 2018 XIII International Confer-
ence on Electrical Machines (ICEM), pages 2345–2351. IEEE, 2018. [46] P. A. Panagiotou, I. Arvanitakis, N. Lophitis, J. Antonino-Daviu, and K. N. Gyftakis. A new approach for broken
rotor bar detection in induction motors using frequency extraction in stray flux signals. IEEE Transactions on Industry
Applications, 2019. pp
,
[47] K. Pandey, P. Zope, and S. Suralkar. Review on fault diagnosis in three-phase induction motor. MEDHA–2012,
Proceedings published by International Journal of Computer Applications (IJCA), 2012. [48] J. Rafiee, F. Arvani, A. Harifi, and M. Sadeghi. Intelligent condition monitoring of a gearbox using artificial neural
network. Mechanical systems and signal processing, 21(4):1746–1754, 2007. y
g
p
g
[49] A. Sadeghian, Z. Ye, and B. Wu. Online detection of broken rotor bars in induction motors by wavelet packet decom-
position and artificial neural networks. IEEE Transactions on Instrumentation and Measurement, 58(7):2253–2263,
2009. References Handbook of neural network signal processing. CRC press, 2001. [27] M. E. Iglesias-Martínez, J. A. Antonino-Daviu, P. Fernández de Córdoba, and J. A. Conejero. Rotor fault detection in
induction motors based on time-frequency analysis using the bispectrum and the autocovariance of stray flux signals. Energies, 12(4):597, 2019. [28] M. E. Iglesias-Martinez, P. F. de Cordoba, J. Antonino-Daviu, and J. A. Conejero. Detection of nonadjacent rotor faults
in induction motors via spectral subtraction and autocorrelation of stray flux signals. IEEE Transactions on Industry
Applications, 55(5):4585–4594, 2019. pp
( )
[29] M. E. Iglesias-Martínez, P. F. de Córdoba, J. A. Antonino-Daviu, and J. A. Conejero. Detection of bar breakages in
induction motor via spectral subtraction of stray flux signals. In 2018 XIII International Conference on Electrical 13 HOSA of Stray Flux Signals for Faults Detection in Induction Motors Machines (ICEM), pages 1796–1802. IEEE, 2018 p g
[30] M. E. Iglesias-Martínez, P. F. de Córdoba, J. A. Antonino-Daviu, and J. A. Conejero. Detection of adjacent and non-
adjacent bar breakages in induction motors via convolutional analysis of sound signals. Preprint, 2020. [31] F. Immovilli, A. Bellini, R. Rubini, and C. Tassoni. Diagnosis of bearing faults in induction machines by vibration or
current signals: A critical comparison. IEEE Transactions on Industry Applications, 46(4):1350–1359, 2010. [32] C. Jiang, S. Li, and T. G. Habetler. A review of condition monitoring of induction motors based on stray flux. In 2017
IEEE Energy Conversion Congress and Exposition (ECCE), pages 5424–5430. IEEE, 2017. [33] L. Jiang, Y. Liu, X. Li, and S. Tang. Using bispectral distribution as a feature for rotating machine
Measurement, 44(7):1284–1292, 2011. [34] Q. Jiang and F. Chang. A novel rolling-element bearing faults classification method combines lower-order moment
spectra and support vector machine. Journal of Mechanical Science and Technology, 33(4):1535–1543, 2019. [35] X. Jin and T. W. Chow. Anomaly detection of cooling fan and fault classification of induction motor using mahalanobis–
taguchi system. Expert Systems with Applications, 40(15):5787–5795, 2013. g
y
p
y
pp
(
)
[36] J. Józwik. Identification and monitoring of noise sources of CNC machine tools by acoustic holography methods. Advances in Science and Technology Research Journal, 10(30), 2016. gy
(
)
[37] S. M. Kay. Fundamentals of statistical signal processing. Prentice Hall PTR, 1993. y
f
g
p
g
[38] R. Liu, B. Yang, E. Zio, and X. Chen. Artificial intelligence for fault diagnosis of rotating machinery: A review. HOSA of Stray Flux Signals for Faults Detection in Induction Motors References [50] L. Saidi, J. B. Ali, and F. Fnaiech. Application of higher order spectral features and support vector machines for bearing
faults classification. ISA transactions, 54:193–206, 2015. [51] L. Saidi, F. Fnaiech, G. Capolino, and H. Henao. Stator current bi-spectrum patterns for induction machines multiple-
faults detection. In IECON 2012-38th Annual Conference on IEEE Industrial Electronics Society, pages 5132–5137. IEEE, 2012. [52] L. Saidi, F. Fnaiech, H. Henao, G. Capolino, and G. Cirrincione. Diagnosis of broken-bars fault in induction machines
using higher order spectral analysis. ISA Transactions, 52(1):140–148, 2013. [53] M. Salah, K. Bacha, and A. Chaari. An improved spectral analysis of the stray flux component fo
air-gap irregularities in squirrel cage motors. ISA transactions, 53(3):816–826, 2014. [53] M. Salah, K. Bacha, and A. Chaari. An improved spectral analysis of the stray flux component for the detection of
air-gap irregularities in squirrel cage motors. ISA transactions, 53(3):816–826, 2014. [54] B Samanta Gear fault detection using artificial neural networks and support vector machines with genetic algorithms air-gap irregularities in squirrel cage motors. ISA transactions, 53(3):816–826, 2014. [54] B. Samanta. Gear fault detection using artificial neural networks and support vector machines with genetic algorithms. Mechanical systems and signal processing, 18(3):625–644, 2004. [54] B. Samanta. Gear fault detection using artificial neural networks and support vector machines with g
Mechanical systems and signal processing, 18(3):625–644, 2004. y
g
p
g
[55] P. Sangeetha and S. Hemamalini. Dyadic wavelet transform-based acoustic signal analysis for torque prediction of a
three-phase induction motor. IET Signal Processing, 11(5):604–612, 2017. p
g
g
[56] J. Sanz, R. Perera, and C. Huerta. Gear dynamics monitoring using discrete wavelet transformation and multi-layer
perceptron neural networks. Applied Soft Computing, 12(9):2867–2878, 2012. 14 M.E. Iglesias-Martínez et al. Applied Mathematics and Nonlinear Sciences (aop) 1–14 [57] Z. Shen, X. Chen, X. Zhang, and Z. He. A novel intelligent gear fault diagnosis model based on emd and multi-class
tsvm. Measurement, 45(1):30–40, 2012. ( )
[58] A. Singhal and M. A. Khandekar. Bearing fault detection in induction motor using fast fourier transf
Conf. on Advanced Research in Engineering & Technology, 2013. M. A. Khandekar. Bearing fault detection in induction motor using fast fourier transform. In IEEE Int. ced Research in Engineering & Technology, 2013. f
g
g
gy
[59] A. Soualhi, K. Medjaher, and N. Zerhouni. Bearing health monitoring based on hilbert–huang transform, support vector
machine, and regression. IEEE Transactions on Instrumentation and Measurement, 64(1):52–62, 2014. References [60] A. Swami, G. B. Giannakis, and G. Zhou. Bibliography on higher-order statistics. Signal processing, 60(1):65–126,
1997. [61] O. Vitek, M. Janda, and V. Hajek. Effects of eccentricity on external magnetic field of induction machine. In Melecon
2010-2010 15th IEEE Mediterranean Electrotechnical Conference, pages 939–943. IEEE, 2010. f
p g
[62] H. Wang, X. Bao, C. Di, and Z. Cheng. Detection of eccentricity fault using slot leakage flux monito
International Conference on Power Electronics and ECCE Asia (ICPE-ECCE Asia), pages 2188–21 f
(
), p g
,
[63] Y. Wang, J. Xiang, R. Markert, and M. Liang. Spectral kurtosis for fault detection, diagnosis and prognostics of rotating
machines: A review with applications. Mechanical Systems and Signal Processing, 66:679–698, 2016. pp
y
g
g,
,
[64] Z. Wang and C. Chang. Online fault detection of induction motors using frequency domain independent components
analysis. In 2011 IEEE International Symposium on Industrial Electronics, pages 2132–2137. IEEE, 2011. [65] Z. Wang, C. Chang, and Y. Zhang. A feature based frequency domain analysis algorithm for fault detection of induction
motors. In 2011 6th IEEE Conference on Industrial Electronics and Applications, pages 27–32. IEEE, 2011. [66] W. Wenbing and X. Jinquan. The application of coupled three order cumulants’ differential feature in fault diagnosis. In 2017 International Conference on Virtual Reality and Visualization (ICVRV), pages 374–375. IEEE, 2017. p g
[67] I. Zamudio-Ramirez, R. A. Osornio-Rios, M. Trejo-Hernandez, R. d. J. Romero-Troncoso, and J. A
Smart-sensors to estimate insulation health in induction motors via analysis of stray flux. Energies, [67] I. Zamudio-Ramirez, R. A. Osornio-Rios, M. Trejo-Hernandez, R. d. J. Romero-Troncoso, and J. A. Antonino-Daviu. Smart-sensors to estimate insulation health in induction motors via analysis of stray flux. Energies, 12(9):1658, 2019. [68] X. Zhang and J. Zhou. Multi-fault diagnosis for rolling element bearings based on ensemble empirical mode decom-
position and optimized support vector machines. Mechanical Systems and Signal Processing, 41(1-2):127–140, 2013. [69] W. Zhao, T. Tao, and E. Zio. System reliability prediction by support vector regression with analytic selection and
genetic algorithm parameters selection. Applied Soft Computing, 30:792–802, 2015. y
y
g
,
( )
,
[68] X. Zhang and J. Zhou. Multi-fault diagnosis for rolling element bearings based on ensemble empirical mode decom-
position and optimized support vector machines. Mechanical Systems and Signal Processing, 41(1-2):127–140, 2013. [71] F. Zidat, J.-P. Lecointe, F. Morganti, J.-F. Brudny, T. Jacq, and F. Streiff. Non invasive sensors for monitoring the
efficiency of ac electrical rotating machines. Sensors, 10(8):7874–7895, 2010. References [69] W Zhao T Tao and E Zio
System reliability prediction by support vector regression with analytic selection and p
p
pp
y
g
g
[69] W. Zhao, T. Tao, and E. Zio. System reliability prediction by support vector regression with analytic selection and
genetic algorithm parameters selection. Applied Soft Computing, 30:792–802, 2015. [70] W. Zhao, Y. Zhang, and Y. Zhu. Diagnosis for transformer faults based on combinatorial Bayes Network. In 2009 2nd
International Congress on Image and Signal Processing, pages 1–3. IEEE, 2009. [71] F. Zidat, J.-P. Lecointe, F. Morganti, J.-F. Brudny, T. Jacq, and F. Streiff. Non invasive sensors for monitoring the
efficiency of ac electrical rotating machines. Sensors, 10(8):7874–7895, 2010.
|
https://openalex.org/W2075455992
|
https://europepmc.org/articles/pmc4391609?pdf=render
|
English
| null |
VEGF Correlates with Inflammation and Fibrosis in Tuberculous Pleural Effusion
|
The scientific world journal/TheScientificWorldjournal
| 2,015
|
cc-by
| 5,900
|
Hindawi Publishing Corporation
e Scientific World Journal
Volume 2015, Article ID 417124, 8 pages
http://dx.doi.org/10.1155/2015/417124 Hindawi Publishing Corporation
e Scientific World Journal
Volume 2015, Article ID 417124, 8 pages
http://dx.doi.org/10.1155/2015/417124 Hindawi Publishing Corporation
e Scientific World Journal
Volume 2015, Article ID 417124, 8 pages
http://dx.doi.org/10.1155/2015/417124 Mauo-Ying Bien,1,2 Ming-Ping Wu,3,4 Wei-Lin Chen,5 and Chi-Li Chung1,2 Mauo-Ying Bien,1,2 Ming-Ping Wu,3,4 Wei-Lin Chen,5 and Chi-Li Chung1,2
1School of Respiratory Therapy, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
2Division of Pulmonary Medicine, Department of Internal Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan
3Department of Obstetrics and Gynecology, Chi-Mei Medical Center, Tainan 710, Taiwan
4Department of Obstetrics and Gynecology, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
5Graduate Institute of Medical Sciences and Department of Pharmacology, College of Medicine, Taipei Medical University,
Taipei 110, Taiwan Correspondence should be addressed to Chi-Li Chung; clchung@tmu.edu.tw Correspondence should be addressed to Chi-Li Chung; clchung@tmu.edu.tw Received 25 September 2014; Accepted 3 December 2014 Received 25 September 2014; Accepted 3 December 2014 Academic Editor: Muniyan Sakthivel Copyright © 2015 Mauo-Ying Bien et al. This is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited. Objective. To investigate the relationship among angiogenic cytokines, inflammatory markers, and fibrinolytic activity in
tuberculous pleural effusion (TBPE) and their clinical importance. Methods. Forty-two patients diagnosed with TBPE were studied. Based on chest ultrasonography, there were 26 loculated and 16 nonloculated TBPE patients. The effusion size radiological scores
and effusion vascular endothelial growth factor (VEGF), interleukin- (IL-) 8, plasminogen activator inhibitor type-1 (PAI-1), and
tissue type plasminogen activator (tPA) were measured. Treatment outcome and pleural fibrosis, defined as radiological residual
pleural thickening (RPT), were assessed at 6-month follow-up. Results. The effusion size and effusion lactate dehydrogenase (LDH),
VEGF, IL-8, PAI-1, and PAI-1/tPA ratio were significantly higher, while effusion glucose, pH value, and tPA were significantly lower,
in loculated than in nonloculated TBPE. VEGF and IL-8 correlated positively with LDH and PAI-1/tPA ratio and negatively with
tPA in both loculated and nonloculated TBPE. Patients with higher VEGF or greater effusion size were prone to develop RPT
(𝑛= 14; VEGF, odds ratio 1.28, 𝑃= 0.01; effusion size, odds ratio 1.01, 𝑃= 0.02), and VEGF was an independent predictor of RPT
in TBPE (receiver operating characteristic curve AUC = 0.985, 𝑃< 0.001). Conclusions. Effusion VEGF correlates with pleural
inflammation and fibrosis and may be targeted for adjunct therapy for TBPE. 2. Methods 2.1. Study Design. This single-center prospective study
intended to assess the clinical importance of angiogenic
cytokines and fibrinolytic activity in TBPE. Ethics approval
(CRC-05-11-01) was obtained from the Institutional Review
Board of Taipei Medical University (Taipei, Taiwan), and all
patients gave written informed consent before entering the
study. 2.2. Patient Selection. Consecutive patients with pleural effu-
sion (PE) of unknown cause admitted to Taipei Medical
University Hospital were eligible for this study and were
included when a diagnosis of TBPE was established by the
demonstration of granulomatous pleuritis on closed pleura
biopsy specimens with or without the presence of acid-
fast bacilli. Exclusion criteria were as follows: history of
invasive procedures directed into the pleural cavity; recent
severe trauma, hemorrhage, or stroke; bleeding disorder or
anticoagulant therapy; use of streptokinase in the previous 2
years; and lack of dyspnea caused by effusions. 2.2. Patient Selection. Consecutive patients with pleural effu-
sion (PE) of unknown cause admitted to Taipei Medical
University Hospital were eligible for this study and were
included when a diagnosis of TBPE was established by the
demonstration of granulomatous pleuritis on closed pleura
biopsy specimens with or without the presence of acid-
fast bacilli. Exclusion criteria were as follows: history of
invasive procedures directed into the pleural cavity; recent
severe trauma, hemorrhage, or stroke; bleeding disorder or
anticoagulant therapy; use of streptokinase in the previous 2
years; and lack of dyspnea caused by effusions. 2.8. Outcome Measures. CXR and pulmonary function test-
ing with spirometry were performed on discharge and 6
months later, respectively. RPT was measured and defined as
a lateral pleural thickening of ≥10 mm shown on CXR and
confirmed by chest US or CT at the end of 6-month follow-
up [16]. 2.8. Outcome Measures. CXR and pulmonary function test-
ing with spirometry were performed on discharge and 6
months later, respectively. RPT was measured and defined as
a lateral pleural thickening of ≥10 mm shown on CXR and
confirmed by chest US or CT at the end of 6-month follow-
up [16]. 2.9. Statistical Analysis. Data were expressed as mean ± SD,
median (interquartile range or range), or frequency (%),
where appropriate. Comparisons of continuous data were
made using an unpaired 𝑡-test or Mann-Whitney 𝑈test
between two groups where appropriate. The correlations
between variables were determined by Spearman rank corre-
lation coefficients. 1. Introduction Pleural fluid analyses, adenosine deaminase (ADA),
and microbiological studies were performed routinely. 2.6. Measurement of Effusion VEGF, IL-8, PAI-1, and tPA. The
commercially available enzyme-linked immunosorbent assay
kits were used to measure effusion levels of VEGF, IL-8 (R & D
System; Minneapolis, MN, USA), tPA, and PAI-1 (American
Diagnostica; Greenwich, CT, USA) as previously described
[6]. 2.7. Management of TBPE. Standard anti-TB medications
in addition to pigtail drainage were administered once TB
pleurisy was diagnosed. Intrapleural injection therapy started
on the following day and was done once daily for three con-
tinuous days. Patients with nonloculated effusion underwent
intrapleural injection with 50 mL normal saline. Patients
with loculated effusions received intrapleural injection with
solutions containing 50 mL normal saline with 250,000 IU of
dissolved streptokinase (Aventis, Marburg, Germany). After
injection, the pigtail tube was clamped for 2 hours and
then opened for free drainage. CXR was performed after the
third day of treatment. Complete drainage was defined as no
or minimal pleural effusion on CXR. The pigtail tube was
removed when the net drainage was less than 50 mL during
the previous 24 hours. 1. Introduction presentation of TBPE [6]. Loculated effusion, defined as
effusion that does not move freely in the pleural space due
to fibrinous adhesion between parietal and visceral pleura,
makes reabsorption or drainage of such fluid collection
very difficult and leads to persistent dyspnea [6]. Fibrin
turnover in the pleural cavity is affected by fibrinolytic activity
mediated by plasmin, which is regulated by the equilibrium
between plasminogen activators (PAs) and plasminogen
activator inhibitors (PAIs) [7]. An imbalance between PAI-1
and tissue type plasminogen activator (tPA) may elicit fibrin
gel formation in the pleural space and lead to pleural fluid
loculation, fibrin neomatrix remodeling, and fibrosis [6, 8].i Tuberculosis (TB) remains a major global public health issue
and continues to cause significant morbidity and mortality
worldwide [1]. Tuberculous pleural effusion (TBPE) is the
most common form of extrapulmonary TB and often compli-
cated with pleural fibrosis [2]. This pleural fluid is enriched
in proteins, inflammatory cells, and various angiogenic
cytokines [3], including vascular endothelial growth factor
(VEGF) and interleukin- (IL-) 8, which stimulate migration
of leukocytes, induce vascular hyperpermeability and pleural
fluid production, activate coagulation cascade, and repress
fibrinolytic activity within the pleural cavity [4, 5].i VEGF may facilitate the genesis of fibrin gel in infectious
pleural effusions [9]. Previous studies reported that VEGF i
Fluid loculation with fibrin septation, a hallmark of
pleural inflammation, is commonly found to be the initial The Scientific World Journal 2 might play a role in the modulation of tPA and PAI-1
[10] and that anti-VEGF antibody could reduce fluid vol-
ume of inflammatory pleural effusion and attenuate pleural
inflammation and fibrosis [11–13]. These findings suggest that
VEGF may be involved in the regulation of inflammation,
fibrin turnover and fluid loculation in the pleural cavity, and
subsequent residual pleural thickening (RPT) or fibrosis [9],
which was observed in our previous study on parapneumonic
effusions [14]. However, the clinical relevance of angiogenic
cytokines and fibrinolytic activity in TBPE remains unclear. The aim of the present study was to evaluate the relationship
among angiogenic cytokines (VEGF, IL-8), inflammatory
markers (lactate dehydrogenase (LDH), glucose, pH value),
and fibrinolytic parameters (tPA and PAI-1) in TBPE and
their clinical implication. 2.5. Thoracentesis and Pleural Fluid Analysis. With the guid-
ance of chest US, 50 mL of pleural fluid was aspirated imme-
diately or within 24 hours after hospitalization. When PE
was multiloculated, the fluid was aspirated from the largest
loculus. 2. Methods Categorical variables between two groups
were examined using 𝜒2 method and/or Fisher’s exact test,
when appropriate. A two-tailed 𝑃value <0.05 was considered
to be statistically significant. 2.3. Imaging of PE. All patients were subjected to routine
chest radiography (CXR, frontal and lateral views), lateral
decubitus view with the lesioned side down, real-time chest
ultrasonography (US), and/or thoracic computed tomogra-
phy (CT) to determine the loculated or nonloculated PE as
previously described [6]. Loculated effusion was diagnosed
if the fluid collection (1) appeared as a fixed lenticular
shape on a frontal CXR and was unchanged in appearance
on a decubitus CXR or (2) had a lobulated or lentiform
configuration with a convex smooth border on chest US or
CT imaging. i
Multivariate logistic regression analyses were performed
to determine factors independently associated with develop-
ment of RPT. Variables found to be significant in the uni-
variate analysis were entered into a binary logistic regression
analysis. Results of multivariable analyses are reported as
odds ratios (OR) with 95% confidence intervals and 𝑃values. The optimal sensitivity, specificity, and cutoff value of pleural
fluid variables to predict RPT were evaluated by the receiver
operating characteristics (ROC) by analyzing the area under
the curve (AUC). 2.4. CXR Scoring. The posteroanterior CXR films were read
and scored by two radiologists who were blind to any clinical
information to determine (a) the largest linear width of
pleural opacity and (b) effusion size CXR score: the estimated
overall percentage of pleural shadowing in the hemithorax
[15]. 2.4. CXR Scoring. The posteroanterior CXR films were read
and scored by two radiologists who were blind to any clinical
information to determine (a) the largest linear width of
pleural opacity and (b) effusion size CXR score: the estimated
overall percentage of pleural shadowing in the hemithorax
[15]. The Scientific World Journal 3 Table 1: Demographic and clinical data of the patients studied. Table 1: Demographic and clinical data of the patients studied. Table 1: Demographic and clinical data of the patients studied. 2. Methods No significant differences between the two groups
were found in terms of age, gender, comorbidities, and dura-
tion of illness before treatment. Patients with loculated TBPE 2. Methods All patients
Loculated TBPE
Nonloculated TBPE
𝑃value†
(𝑛= 42)
(𝑛= 26)
(𝑛= 16)
Male, 𝑛(%)
27 (64)
18 (69)
9 (56)
0.511
Age, yrs, mean ± SD
62 ± 21
61 ± 22
63 ± 21
0.824
Patients with comorbidities, 𝑛(%)∗
28 (67)
18 (70)
10 (63)
0.742
Symptom onset to treatment, days, median (range)
10 (7–19)
10 (8–20)
10 (6–16)
0.547
Side of pleural effusion
Right/left, 𝑛(%)
27/15 (64/36)
17/9 (65/35)
10/6 (63/37)
0.733
TBPE: uncomplicated parapneumonic effusion. ∗Comorbidities including alcoholism, diabetes mellitus, neurologic, cardiac, respiratory, liver, and kidney diseases. †For comparisons between loculated and nonloculated TBPE groups. f
ing alcoholism, diabetes mellitus, neurologic, cardiac, respiratory, liver, and kidney diseases. ween loculated and nonloculated TBPE groups. Table 2: Pleural effusion variables between loculated and nonloculated tuberculous pleural effusion. Table 2: Pleural effusion variables between loculated and nonloculated tuberculous pleural effusion. All patients
Loculated TBPE
Nonloculated TBPE
𝑃value†
(𝑛= 42)
(𝑛= 26)
(𝑛= 16)
Effusion CXR score, %, mean ± SD
53 ± 20
56 ± 21
43 ± 12
0.025
ADA, IU/L
99
108
86
0.100
(66–185)
(82–203)
(59–149)
pH value
7.30
7.27
7.36
<0.001
(7.22–7.35)
(7.22–7.30)
(7.33–7.41)
Glucose, mg/dL
116
98
120
0.038
(75–138)
(75–118)
(99–142)
Protein, g/L
5.0
4.8
5.2
0.089
(4.1–5.3)
(4.1–5.2)
(4.2–5.6)
LDH, IU/dL
307
387
210
0.002
(229–533)
(287–723)
(154–388)
Leukocyte count, cells/𝜇L
1598
1665
1437
0.449
(963–3880)
(1330–3880)
(720–2000)
PAI-1, ng/mL
114.6
138.5
105.5
<0.001
(105.5–199.0)
(114.8–213.0)
(96.0–113.0)
tPA, ng/mL
17.0
15.9
24.9
<0.01
(10.0–23.0)
(8.4–20.5)
(14.4–28.7)
PAI-1/tPA ratio
7.6
13.4
4.6
0.036
(5.0–14.0)
(7.6–18.4)
(1.8–6.8)
IL-8, pg/mL
365
419
167
<0.001
(220–637)
(312–1442)
(79–395)
VEGF, pg/mL
693
969
510
<0.001
(499–1909)
(571–2054)
(161–713)
TBPE: tuberculous pleural effusion; effusion CXR score: portion of hemithorax opacified by pleural effusion on posteroanterior chest radiograph; ADA:
adenosine deaminase; LDH: lactate dehydrogenase; PAI-1: plasminogen activator inhibitor-1; tPA: tissue type plasminogen activator; IL-8: interleukin-8; VEGF:
vascular endothelial growth factor. Data are presented as median (IQR) unless specified. † 3.2. Comparisons between Loculated and Nonloculated TBPE. There were 26 patients with loculated TBPE and 16 patients
with nonloculated TBPE (Table 1). Clinical data, pleural fluid
characteristics, angiogenic cytokines, and parameters related
to fibrinolytic activities in pleural fluids are shown in Table 2. Compared to patients with nonloculated TBPE, loculated
TBPE patients had significantly higher effusion CXR score on
admission. 3. Results Table 4: Pleural fluid variables and pulmonary function in patients with or without development of residual p and nonloculated TBPE. However, there was no significant
correlation between the effusion size and the effusion levels
of IL-8. had significantly higher levels of effusion LDH, VEGF, IL-8,
PAI-1, and PAI-1/tPA ratio, and lower values of pH, glucose,
and tPA than did nonloculated TBPE patients. Moreover,
the ADA level, protein concentrations, and leukocyte counts
were comparable between two groups. 3.4. Comparisons between TBPE Patients with and without
RPT. All patients were successfully treated with anti-TB
medications and intrapleural instillation of normal saline or
streptokinase and were discharged uneventfully. All patients
finished the 6-month anti-TB medications and improved
clinically over time, showing no recurrence of the disease. RPT was observed in 14 patients (33%) at the end of 6-
month follow-up (Table 4). All of them (100%) had loculation
of pleural effusions initially. The effusion CXR score on
admission and the effusion levels of leukocyte count, PAI-
1, PAI-1/tPA ratio, IL-8, and VEGF were significantly higher,
and the effusion pH value and tPA were significantly lower in
the patients with RPT than in those without RPT. Moreover, 3.4. Comparisons between TBPE Patients with and without
RPT. All patients were successfully treated with anti-TB
medications and intrapleural instillation of normal saline or
streptokinase and were discharged uneventfully. All patients
finished the 6-month anti-TB medications and improved
clinically over time, showing no recurrence of the disease. RPT was observed in 14 patients (33%) at the end of 6-
month follow-up (Table 4). All of them (100%) had loculation
of pleural effusions initially. The effusion CXR score on
admission and the effusion levels of leukocyte count, PAI-
1, PAI-1/tPA ratio, IL-8, and VEGF were significantly higher,
and the effusion pH value and tPA were significantly lower in
the patients with RPT than in those without RPT. Moreover, 3.3. Correlations among Effusion Angiogenic Cytokines, Fibri-
nolytic Parameters, Pleural Fluid Characteristics, and Effusion
CXR Score. As shown in Table 3, the effusion levels of IL-8
and VEGF were positively correlated with those of LDH and
PAI-1/tPA ratio and negatively correlated with those of tPA in
both loculated and nonloculated TBPE. 3. Results 3.1. Patient Characteristics. Consecutive 50 patients with
TBPE were eligible for this study. Eight patients were
excluded because of recent stroke in three, recent gastroin-
testinal bleeding in two, and informed consent unavailable
in three cases, respectively. Finally, 42 patients were enrolled,
including 27 men and 15 women with an age range from 22
to 91 years (mean age, 62 years) (Table 1), and all completed 6
months of follow-up from March 2011 through June 2014. The Scientific World Journal 4 Table 3: Correlation among angiogenic cytokines, fibrinolytic parameters, pleural fluid characteristics, and effusion CXR scores. pH
Glucose
LDH
Leukocyte count
PAI-1
tPA
PAI-1/tPA ratio
Effusion CXR score
Loculated TBPE (𝑛= 26)
IL-8
−0.42∗
−0.40∗
0.39∗
0.36
0.28
−0.40∗
0.42∗
0.21
VEGF
−0.57†
−0.58†
0.49∗
0.25
0.77‡
−0.53†
0.76‡
0.63‡
Effusion CXR score
−0.14
−0.12
−0.18
0.13
0.39∗
−0.22
0.12
—
Nonloculated TBPE (𝑛= 16)
IL-8
−0.46
−0.48
0.55∗
0.28
0.24
−0.62†
0.59∗
0.32
VEGF
−0.52∗
−0.56∗
0.67†
0.17
0.59∗
−0.44∗
0.43∗
0.47∗
Effusion CXR score
−0.22
−0.29
−0.11
0.29
0.21
−0.11
0.10
—
See Table 2 for definition of the abbreviations. ∗Correlation is statistically significant at the level of 0.05. †Correlation is statistically significant at the level of 0.01. ‡Correlation is statistically significant at the level of 0.001. See Table 2 for definition of the abbreviations. ∗i Table 4: Pleural fluid variables and pulmonary function in patients with or without development of residual pleural thickening (RPT). RPT (+)
RPT (−)
𝑃value
(𝑛= 14)
(𝑛= 28)
Effusion status
Effusion CXR score, %, mean ± SD
71 ± 20
44 ± 12
<0.001
Loculation, 𝑛(%)
14 (100)
0 (0)
0.002
Pleural fluid
pH value
7.27 (7.22–7.30)
7.35 (7.25–7.39)
0.013
Glucose, mg/dL
100 (73–140)
106 (76–129)
0.947
LDH, IU/dL
328 (229–666)
289 (154–532)
0.126
Leukocyte count, cells/𝜇L
2840 (1521–4410)
1437 (720–2000)
0.028
PAI-1, ng/mL
143.1 (111.1–208.0)
113.7 (78.0–122.5)
0.043
tPA, ng/mL
10.4 (8.2–12.7)
15.8 (4.8–21.0)
0.028
PAI-1/tPA ratio
11.7 (5.0–16.7)
5.2 (2.9–8.4)
<0.001
IL-8, pg/mL
419 (312–985)
248 (96–502)
0.025
VEGF, pg/mL
2054 (1909–3387)
516 (274–693)
<0.001
FVC, % predicted
At 6 months
74 (73–75)
80 (79–81)
<0.001
See Table 2 for definition of the abbreviations. RPT: residual pleural thickening ≥10 mm shown on CXR at the end of 6-month follow-up; FVC: forced vital
capacity. Data are presented as median (IQR) unless specified. riables and pulmonary function in patients with or without development of residual pleural thickening (RPT). 3. Results In addition, VEGF
correlated positively with PAI-1 and negatively with pH
value and glucose in both loculated and nonloculated TBPE,
suggesting that VEGF is implicated in pleural inflammation
and fibrinogenesis.hfi i
The effusion CXR score had significant positive corre-
lation with the effusion levels of VEGF in both loculated The Scientific World Journal 5 0
80
20
40
60
100
0
20
40
60
80
100
VEGF
Sensitivity (%)
P < 0.0001
AUC = 0.985
100 −specificity (%)
(a)
0
20
40
60
80
100
Effusion CXR score
Sensitivity (%)
0
80
20
40
60
100
AUC = 0.869
P = 0.0001
100 −specificity (%)
(b)
Figure 1: Receiver operating characteristic curves for (a) effusion vascular endothelial growth factor (VEGF) level and (b) effusion chest
radiography (CXR) score to predict residual pleural thickening (RPT) in tuberculous pleural effusion (TBPE). AUC = area under the curve. 0
80
20
40
60
100
0
20
40
60
80
100
VEGF
Sensitivity (%)
P < 0.0001
AUC = 0.985
100 −specificity (%)
(a) 0
20
40
60
80
100
Effusion CXR score
Sensitivity (%)
0
80
20
40
60
100
AUC = 0.869
P = 0.0001
100 −specificity (%)
(b) Effusion CXR score Sensitivity (%) (b) (a) Figure 1: Receiver operating characteristic curves for (a) effusion vascular endothelial growth factor (VEGF) level and (b) effusion chest
radiography (CXR) score to predict residual pleural thickening (RPT) in tuberculous pleural effusion (TBPE). AUC = area under the curve. Table 5: Multivariate logistic regression analyses of factors associ-
ated with residual pleural thickening (RPT). patients with RPT had significant lower forced vital capacity
(FVC) than those without RPT. Table 5: Multivariate logistic regression analyses of factors associ
ated with residual pleural thickening (RPT). Odds
ratio
95% CI
𝑃value
Effusion status
Effusion CXR score, %
1.01
1.00–1.02
0.02
Loculation
1.00
0.99-1.00
0.99
Pleural fluid
pH value
1.01
0.98–1.04
0.52
Leukocyte count, cells/𝜇L
1.00
0.99-1.00
0.87
PAI-1, ng/mL
0.99
0.97–1.03
0.76
tPA, ng/mL
1.00
0.99-1.00
0.99
PAI-1/tPA ratio
1.01
0.98–1.04
0.52
IL-8, pg/mL
1.00
0.99-1.00
0.93
VEGF, pg/mL
1.28
1.06–1.51
0.01
See Table 2 for definition of the abbreviations. CI: confidence interval. 3.5. Multivariate Logistic Regression Analysis. Furthermore,
multivariate logistic regression analysis was used to iden-
tify the independent factors associated with RPTin TBPE
after 6-month anti-TB medications (Table 5). 3. Results Variables of
significance in univariate analysis were included for analysis
which demonstrated that only higher effusion VEGF level
and greater effusion CXR score were independent predictors
for RPT in TBPE. 3.6. Optimal Sensitivity, Specificity, and Cutoff Value of
Variables to Predict RPT. The ROC curve showed that the
effusion VEGF at the cutoff level >842 pg/mL had the highest
sensitivity and specificity for predicting RPT in TBPE patients
(area under the ROC curve = 0.985, 95% CI = 0.957–1.012;
sensitivity 100%, 95% CI = 76.8–100%; specificity 89.3%,
95% CI = 71.8–97.7%) (Figure 1(a)), followed by effusion
CXR score >62% (area under the ROC curve = 0.869, 95%
CI = 0.757–0.981; sensitivity 64.3%, 95% CI = 35.1–87.2%;
specificity 92.9%, 95% CI = 76.5–99.1%) (Figure 1(b)). To our knowledge, this is the first study to demonstrate that
VEGF correlated significantly with TB pleural inflammation
and fibrinolytic activity and that elevated VEGF level was
associated with development of pleural fibrosis in TBPE. i
Previous studies showed that the level of VEGF was
consistently higher in exudative than in transudative pleural
effusions [17, 18] and TBPE contained significantly higher lev-
els of VEGF than did pleural fluid of heart failure patient [19]. Another report demonstrated that compared to patients with
inactive pulmonary TB and control subjects, serum VEGF
levels were increased in patients with active pulmonary TB
and were decreased after successful treatment, indicating that
VEGF may serve as a marker of disease activity [20]. Likewise,
the present study revealed that VEGF levels were significantly
higher in loculated than in nonloculated TBPE and correlated
substantially with pleural inflammatory markers such as
LDH, pH, and glucose in both groups. As pleural inflam-
mation and increased vascular permeability and leakage are 4. Discussion Our results demonstrated that effusion size, LDH, VEGF, IL-
8, PAI-1, and PAI-1/tPA ratio were significantly higher, while
effusion glucose, pH value, and tPA were significantly lower,
in loculated than in nonloculated TBPE. VEGF and IL-8
correlated positively with LDH and PAI-1/tPA ratio and neg-
atively with tPA in both loculated and nonloculated TBPE. Additionally, VEGF had positive correlation with effusion
size in both loculated and nonloculated TBPE. Fourteen
patients who developed RPT at the end of 6-month follow-up
had larger effusion size and higher levels of VEGF and PAI-1/
tPA ratio than those who did not. Moreover, VEGF and
effusion size were independent predictors of RPT in TBPE. 6 The Scientific World Journal 6 essential for the development of exudative PE, VEGF may
represent a key mediator in pleural fluid formation [21]. In
parallel, our data disclosed a substantial correlation between
effusion VEGF level and effusion CXR score in both loculated
and nonloculated TBPE. All these results suggest that VEGF
is implicated in pleural inflammation and may be crucial for
the formation of TBPE. optimal sensitivity and specificity to predict RPT in TBPE. At
variance with the previous reports [6, 30], our study indicated
that the presence of loculation did not increase the risk of
pleural fibrosis. The discrepancy may be explained in part by
the fact that all loculated TBPE patients in the present study
received chest US-guided drainage and streptokinase irriga-
tion, which may minimize the effect of effusion loculation on
the occurrence of RPT [15]. Collectively, in agreement with
the previous in vivo reports [11–13], our study indicated that
the increased angiogenic activity in the pleural fluid might
contribute to subsequent development of pleural fibrosis
and signified the role of VEGF-related impaired fibrinolytic
activity in the formation of RPT in TBPE. VEGF induces extravascular leakage of plasma proteins
and is important in the modulation of extracellular matrix
proteolysis by regulating the expression of tPA and PAI-
1 in endothelial cells [10]. Furthermore, VEGF has been
reported to increase PAI-1 expression in keloid fibroblasts
and to contribute to dermal fibrosis [22]. Another angiogenic
factor IL-8 has been shown to increase vascular permeability
and fluid exudation in endotoxin-induced pleurisy in vivo
[23] and correlated positively with PAI-1 and negatively
with tPA in exudative PE [24]. 4. Discussion All these findings indicate
that angiogenic cytokines may elicit exudative effusions and
modulate fibrinolytic activity in pleural space by altering
the balance of PAI-1 and tPA. In line with the previous
reports [10, 22–24], our data demonstrated that in both
loculated and nonloculated TBPE, the levels of VEGF and IL-
8 correlated positively with the values of PAI-1/tPA ratio and
negatively with tPA level, though only VEGF levels correlated
positively with PAI-1 values. In addition, the levels of VEGF,
IL-8, PAI-1, and PAI-1/tPA ratio were significantly higher
and the values of tPA were significantly lower in loculated
than in nonloculated TBPE. These findings are in keeping
with the results of the previous in vitro study [10] and raise
the possibility that angiogenic cytokines, particularly VEGF,
may attenuate pleural fibrinolytic activity by disrupting the
balance of PAI-1 and tPA elaborated by endothelial and/or
mesothelial cells and that the increase in VEGF is associated
with the decrease in fibrinolytic activity and subsequent fibrin
deposition and fluid loculation in TBPE.hi A previous study demonstrated that administration of
corticosteroids, in conjunction with anti-TB therapy, resulted
in more rapid improvement in symptoms of fever and chest
pain and in resolution of effusions in patients with TBPE,
suggesting the beneficial effect of anti-inflammatory agents
on clinical outcome [32]. However, to date, no effective
medical treatment is available for preventing pleural fibrosis
in TBPE [33]. The reason may be that another critical factor in
pleural fibrosis is the formation of fibrinous neomatrix which
results from disorder in fibrin turnover [8]. Transforming
growth factor (TGF)-𝛽, like VEGF [11, 12], could cause
PAI-1/tPA imbalance and disordered fibrin turnover, and
intrapleural injection with anti-TGF-𝛽antibody has been
shown to decrease pleural fibrosis in experimental empyema
in rabbits [34]. Accordingly, the previous studies [32–34] and
our results may justify further researches on the usefulness of
anti-VEGF therapy for TBPE. Taken together, the present study highlighted the pivotal
role of VEGF in orchestration of inflammation, formation
of pleural fluid, impairment of fibrinolysis, and development
of residual fibrosis in TBPE. As prompted by the promising
effect of targeted therapy with antiangiogenic agents on out-
come of patients with metastatic colorectal cancer [35] and
neovascular age-related macular degeneration [36], further
preclinical and clinical trials are required to investigate the
potential use of targeting VEGF as a therapeutic strategy
adjunct to standard anti-TB treatment for TBPE. Abbreviations CT:
Computed tomography
CXR:
Chest radiography
IL-8:
Interleukin-8
PAI-1: Plasminogen activator inhibitor-1
PE:
Pleural effusion
RPT:
Residual pleural thickening
tPA:
Tissue type plasminogen activator
TB:
Tuberculosis
TBPE: Tuberculous pleural effusion
US:
Ultrasonography
VEGF: Vascular endothelial growth factor. i
In this study, fourteen patients who developed RPT at
the end of follow-up presented initially with fluid loculation
and had greater effusion size, higher effusion levels of
VEGF, IL-8, PAI-1, and PAI-1/tPA ratio, and lower effusion
levels of pH and tPA. Furthermore, the multivariate analysis
demonstrated that larger effusion size or higher effusion
level of VEGF was the independent risk factor for develop-
ment of RPT. Our results also revealed that effusion VEGF
>842 pg/mL, followed by effusion CXR score >62%, had VEGF: Vascular endothelial growth factor. 4. Discussion pl
The sequel of RPT of >10 mm may cause significant
functional disturbance [25]. However, the predictors affecting
the development of RPT in patients with TBPE remain
elusive. Previous studies reported that the concentrations
of C-reactive protein, IL-1, IL-8, tumor necrosis factor-
𝛼, transforming growth factor-𝛽1, interferon-𝛾, and PAI-
1 were significantly higher and the values of pH, glucose,
and tPA were significantly lower in TBPE complicated with
RPT than those without [6, 26–30]. Moreover, pleural fluid
loculation or fibrin septation detected by chest US as an initial
presentation may be of value in predicting the development
or occurrence of RPT in TBPE following completion of anti-
TB medication [6, 31]. A previous in vivo study also demon-
strated that angiogenesis was required in the development of
pleural fibrosis [11, 12]. References Bithell, Wintrobe's Clinical Hematology, Lea & Febiger,
Philadelphia, Pa, USA, 1993. [8] S. Idell, W. Girard, K. B. Koenig, J. McLarty, and D. S. Fair,
“Abnormalities of pathways of fibrin turnover in the human
pleural space,” The American Review of Respiratory Disease, vol. 144, no. 1, pp. 187–194, 1991. [24] C. Alem´an, J. Alegre, J. Monasterio et al., “Association between
inflammatory mediators and the fibrinolysis system in infec-
tious pleural effusions,” Clinical Science, vol. 105, no. 5, pp. 601–
607, 2003. [9] S. Idell, A. P. Mazar, P. Bitterman, S. Mohla, and A. L. Harabin,
“Fibrin turnover in lung inflammation and neoplasia,” The
American Journal of Respiratory and Critical Care Medicine, vol. 163, no. 2, pp. 578–584, 2001. [25] A. Candela, J. Andujar, L. Hern´andez et al., “Functional sequelae
of tuberculous pleurisy in patients correctly treated,” Chest, vol. 123, no. 6, pp. 1996–2000, 2003. [10] M. S. Pepper, N. Ferrara, L. Orci, and R. Montesano, “Vascular
endothelial growth factor (VEGF) induces plasminogen acti-
vators and plasminogen activator inhibitor-1 in microvascular
endothelial cells,” Biochemical and Biophysical Research Com-
munications, vol. 181, no. 2, pp. 902–906, 1991. [26] A. de Pablo, V. Villena, J. Echave-Sustaeta, and A. L. Encuentra,
“Are pleural fluid parameters related to the development of
residual pleural thickening in tuberculosis?” Chest, vol. 112, no. 5, pp. 1293–1297, 1997. [27] C. C. Hua, L. C. Chang, Y. C. Chen, and S. C. Chang, “Proin-
flammatory cytokines and fibrinolytic enzymes in tuberculous
and malignant pleural effusions,” Chest, vol. 116, no. 5, pp. 1292–
1296, 1999. [11] Y. B. Guo, I. Kalomenidis, M. Hawthorne, K. S. Parman, K. B. Lane, and R. W. Light, “Pleurodesis is inhibited by anti-vascular
endothelial growth factor antibody,” Chest, vol. 128, no. 3, pp. 1790–1797, 2005. [28] E. Kunter, A. Ilvan, E. Kilic et al., “The effect of pleural fluid
content on the development of pleural thickness,” International
Journal of Tuberculosis and Lung Disease, vol. 6, no. 6, pp. 516–
522, 2002. [12] L. R. Teixeira, F. S. Vargas, M. M. P. Acencio et al., “Blockage of
vascular endothelial growth factor (VEGF) reduces experimen-
tal pleurodesis,” Lung Cancer, vol. 74, no. 3, pp. 392–395, 2011. [13] S. C. C. Ribeiro, F. S. Vargas, L. Antonangelo et al., “Monoclonal
anti-vascular endothelial growth factor antibody reduces fluid
volume in an experimental model of inflammatory pleural
effusion,” Respirology, vol. 14, no. 8, pp. 1188–1193, 2009. [29] F. C. Lin, Y. References [18] F. Economidou, K. M. Antoniou, N. Tzanakis, K. Sfiridaki, N. M. Siafakas, and S. E. Schiza, “Angiogenic molecule Tie-2 and
VEGF in the pathogenesis of pleural effusions,” Respiratory
Medicine, vol. 102, no. 5, pp. 774–779, 2008. [1] C. Dye and B. G. Williams, “The population dynamics and
control of tuberculosis,” Science, vol. 328, no. 5980, pp. 856–861,
2010. [2] J. M. Porcel, “Tuberculous pleural effusion,” Lung, vol. 187, no. 5, pp. 263–270, 2009. [19] T. S. Kiropoulos, K. Kostikas, K. I. Gourgoulianis et al.,
“Vascular endothelial growth factor levels in pleural fluid and
serum of patients with tuberculous pleural effusions,” Chest, vol. 128, no. 1, article 128, pp. 468–469, 2005. [3] V. B. Antony, “Immunological mechanisms in pleural disease,”
European Respiratory Journal, vol. 21, no. 3, pp. 539–544, 2003. [4] K. A. Mohammed, N. Nasreen, J. Hardwick, C. S. Logie, C. E. Patterson, and V. B. Antony, “Bacterial induction of pleural
mesothelial monolayer barrier dysfunction,” The American
Journal of Physiology—Lung Cellular and Molecular Physiology,
vol. 281, no. 1, pp. L119–L125, 2001. [20] F. Alatas, ¨O. Alatas, M. Metintas, A. ¨Ozarslan, S. Erginel, and
H. Yildirim, “Vascular endothelial growth factor levels in active
pulmonary tuberculosis,” Chest, vol. 125, no. 6, pp. 2156–2159,
2004. [21] C. S. Grove and Y. C. G. Lee, “Vascular endothelial growth
factor: the key mediator in pleural effusion formation,” Current
Opinion in Pulmonary Medicine, vol. 8, no. 4, pp. 294–301, 2002. [5] V. C. Broaddus, A. M. Boylan, J. M. Hoeffel et al., “Neutral-
ization of IL-8 inhibits neutrophil influx in a rabbit model of
endotoxin-induced pleurisy,” Journal of Immunology, vol. 152,
no. 6, pp. 2960–2967, 1994. [22] Y. Wu, Q. Zhang, D. K. Ann et al., “Increased vascular endothe-
lial growth factor may account for elevated level of plasminogen
activator inhibitor-1 via activating ERK1/2 in keloid fibroblasts,”
The American Journal of Physiology—Cell Physiology, vol. 286,
no. 4, pp. C905–C912, 2004. [6] C. L. Chung, C. H. Chen, J. R. Sheu, Y. C. Chen, and S. C. Chang,
“Proinflammatory cytokines, transforming growth factor-𝛽1,
and fibrinolytic enzymes in loculated and free-flowing pleural
exudates,” Chest, vol. 128, no. 2, pp. 690–697, 2005. [23] T. Fukumoto, A. Matsukawa, T. Yoshimura et al., “IL-8 is an
essential mediator of the increased delayed-phase vascular per-
meability in LPS-induced rabbit pleurisy,” Journal of Leukocyte
Biology, vol. 63, no. 5, pp. 584–590, 1998. [7] T. C. Conflict of Interests All the authors declare that there is no conflict of interests
regarding the publication of this paper. The Scientific World Journal 7 Acknowledgments [15] C. L. Chung, C. H. Chen, C. Y. Yeh, J. R. Sheu, and S. C. Chang, “Early effective drainage in the treatment of loculated
tuberculous pleurisy,” European Respiratory Journal, vol. 31, no. 6, pp. 1261–1267, 2008. This work was supported by grants from the National Science
Council, Taiwan (NSC 101-2314-B-038-044-MY3), and the
Chi-Mei Medical Center-Taipei Medical University (102CM-
TMU-08). Dr. Mauo-Ying Bien and Dr. Ming-Ping Wu
contributed equally in this work and should be regarded as
first authors together. This work was supported by grants from the National Science
Council, Taiwan (NSC 101-2314-B-038-044-MY3), and the
Chi-Mei Medical Center-Taipei Medical University (102CM-
TMU-08). Dr. Mauo-Ying Bien and Dr. Ming-Ping Wu
contributed equally in this work and should be regarded as
first authors together. [16] D. Jim´enez Castro, G. D´ıaz, E. P´erez-Rodr´ıguez, and R. W. Light, “Prognostic features of residual pleural thickening in
parapneumonic pleural effusions,” European Respiratory Jour-
nal, vol. 21, no. 6, pp. 952–955, 2003. [17] D. S. Cheng, R. M. Rodriguez, E. A. Perkett et al., “Vascular
endothelial growth factor in pleural fluid,” Chest, vol. 116, no. 3, pp. 760–765, 1999. References C. Chen, F. J. Chen, and S. C. Chang, “Cytokines
and fibrinolytic enzymes in tuberculous and parapneumonic
effusions,” Clinical Immunology, vol. 116, no. 2, pp. 166–173,
2005. [30] I. Gerogianni, M. Papala, P. Tsopa et al., “Could IFN-𝛾predict
the development of residual pleural thickening in tuberculous
pleurisy?” Monaldi Archives for Chest Disease—Pulmonary
Series, vol. 69, no. 1, pp. 18–23, 2008. [14] C. L. Chung, S. H. Hsiao, G. Hsiao, J. R. Sheu, W. L. Chen, and S. C. Chang, “Clinical Importance of Angiogenic Cytokines, Fibri-
nolytic Activity and Effusion Size in Parapneumonic Effusions,”
PLoS ONE, vol. 8, no. 1, Article ID e53169, 2013. The Scientific World Journal 8 8 [31] Y. F. Lai, M. C. Su, H. H. Weng, J. T. Wu, and C. T. Chiu,
“Sonographic septation: a predictor of sequelae of tuberculous
pleurisy after treatment,” Thorax, vol. 64, no. 9, pp. 806–809,
2009. [32] C. H. Lee, W. J. Wang, R. S. Lan, Y. H. Tsai, and Y. C. Chiang,
“Corticosteroids in the treatment of tuberculous pleurisy. A
double-blind, placebo-controlled, randomized study,” Chest,
vol. 94, no. 6, pp. 1256–1259, 1988. [33] J. T. Huggins and S. A. Sahn, “Causes and management of
pleural fibrosis,” Respirology, vol. 9, no. 4, pp. 441–447, 2004. [34] C. R. Kunz, M. R. Jadus, G. D. Kukes, F. Kramer, V. N. Nguyen,
and S. A. Sasse, “Intrapleural injection of transforming growth
factor-𝛽antibody inhibits pleural fibrosis in empyema,” Chest,
vol. 126, no. 5, pp. 1636–1644, 2004. [35] E. T. Pavlidis and T. E. Pavlidis, “Role of bevacizumab in
colorectal cancer growth and its adverse effects: a review,” World
Journal of Gastroenterology, vol. 19, no. 31, pp. 5051–5060, 2013. [36] A. Chiang and C. D. Regillo, “Preferred therapies for neovas-
cular age-related macular degeneration,” Current Opinion in
Ophthalmology, vol. 22, no. 3, pp. 199–204, 2011.
|
https://openalex.org/W2606934814
|
https://hal.sorbonne-universite.fr/hal-01509809/file/journal.pone.0175197.pdf
|
English
| null |
Bacterial biofilm under flow: First a physical struggle to stay, then a matter of breathing
|
PloS one
| 2,017
|
cc-by
| 17,138
|
To cite this version: Philippe Thomen, Jérôme Robert, Amaury Monmeyran, Anne-Florence Bitbol, Carine Douarche, et
al.. Bacterial biofilm under flow: First a physical struggle to stay, then a matter of breathing. PLoS
ONE, 2017, 12 (4), pp.e0175197. 10.1371/journal.pone.0175197. hal-01509809 Bacterial biofilm under flow: First a physical struggle to
stay, then a matter of breathing
Philippe Thomen, Jérôme Robert, Amaury Monmeyran, Anne-Florence
Bitbol, Carine Douarche, Nelly Henry ppe Thomen, Jérôme Robert, Amaury Monmeyran, Anne-Florence
Bitbol, Carine Douarche, Nelly Henry Distributed under a Creative Commons Attribution 4.0 International License Philippe Thomen1, Je´roˆme Robert1, Amaury Monmeyran1, Anne-Florence Bitbol1,
Carine Douarche2, Nelly Henry1* 1 Sorbonne Universite´s, UPMC Univ Paris 06 & CNRS, UMR 8237, Laboratoire Jean Perrin, Paris, France,
2 Universite´ Paris Sud, UMR 8502, Laboratoire de Physique des Solides, Orsay, France * nelly.henry@upmc.fr a1111111111
a1111111111
a1111111111
a1111111111
a1111111111 OPEN ACCESS Citation: Thomen P, Robert J, Monmeyran A,
Bitbol A-F, Douarche C, Henry N (2017) Bacterial
biofilm under flow: First a physical struggle to stay,
then a matter of breathing. PLoS ONE 12(4):
e0175197. https://doi.org/10.1371/journal. pone.0175197 Editor: Josue´ Sznitman, Technion Israel Institute of
Technology, ISRAEL Received: September 28, 2016
Accepted: March 22, 2017
Published: April 12, 2017
Copyright: © 2017 Thomen et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which
permits unrestricted use, distribution, and
reproduction in any medium, provided the original
author and source are credited. Copyright: © 2017 Thomen et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which
permits unrestricted use, distribution, and
reproduction in any medium, provided the original
author and source are credited. HAL Id: hal-01509809
https://hal.sorbonne-universite.fr/hal-01509809v1
Submitted on 18 Apr 2017 L’archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d’enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés. HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers. Distributed under a Creative Commons Attribution 4.0 International License RESEARCH ARTICLE a1111111111
a1111111111
a1111111111
a1111111111
a1111111111 Abstract Bacterial communities attached to surfaces under fluid flow represent a widespread lifestyle of
the microbial world. Through shear stress generation and molecular transport regulation,
hydrodynamics conveys effects that are very different by nature but strongly coupled. To deci-
pher the influence of these levers on bacterial biofilms immersed in moving fluids, we quantita-
tively and simultaneously investigated physicochemical and biological properties of the biofilm. We designed a millifluidic setup allowing to control hydrodynamic conditions and to monitor
biofilm development in real time using microscope imaging. We also conducted a transcrip-
tomic analysis to detect a potential physiological response to hydrodynamics. We discovered
that a threshold value of shear stress determined biofilm settlement, with sub-piconewton
forces sufficient to prevent biofilm initiation. As a consequence, distinct hydrodynamic condi-
tions, which set spatial distribution of shear stress, promoted distinct colonization patterns with
consequences on the growth mode. However, no direct impact of mechanical forces on biofilm
growth rate was observed. Consistently, no mechanosensing gene emerged from our differen-
tial transcriptomic analysis comparing distinct hydrodynamic conditions. Instead, we found
that hydrodynamic molecular transport crucially impacts biofilm growth by controlling oxygen
availability. Our results shed light on biofilm response to hydrodynamics and open new ave-
nues to achieve informed design of fluidic setups for investigating, engineering or fighting
adherent communities. Bacterial biofilm under flow: First a physical
struggle to stay, then a matter of breathing Philippe Thomen1, Je´roˆme Robert1, Amaury Monmeyran1, Anne-Florence Bitbol1,
Carine Douarche2, Nelly Henry1* Introduction Data Availability Statement: All relevant data are
within the paper and its Supporting Information
files. Data Availability Statement: All relevant data are
within the paper and its Supporting Information
files. Yet, recently, together with
an increasing interest in micro-organisms on surfaces, attention has emerged towards how bac-
teria respond to mechanical cues, revealing a direct response of attached cells to mechanical
stress applied by shear flow, at the level of gene expression[36–38]. To the best of our knowledge,
such a causal relationship linking mechanical force sensing to gene expression has been clearly
established only at the single-cell level, and not within a three-dimensional biofilm, where it
remains a mere working hypothesis. —namely, molecular transport and mechanical stress. Generally, it is not known whether the
observed phenotypic changes are driven by the alteration of the molecular distribution of a key
compound or by the response of a signaling cascade to mechano-sensing. While mechano-trans-
duction has long been recognized as an integral part of the cell signaling arsenal in eukaryotes
[33, 34], responses to mechanical forces have received less attention in bacteria, except regarding
cell response to osmotic shocks through the mechano-sensitive ion channel Msc, which is direct-
ly stretched open when the membrane is under turgor pressure[35]. Yet, recently, together with
an increasing interest in micro-organisms on surfaces, attention has emerged towards how bac-
teria respond to mechanical cues, revealing a direct response of attached cells to mechanical
stress applied by shear flow, at the level of gene expression[36–38]. To the best of our knowledge,
such a causal relationship linking mechanical force sensing to gene expression has been clearly
established only at the single-cell level, and not within a three-dimensional biofilm, where it
remains a mere working hypothesis. In this work, we study the driving forces underpinning the effects of hydrodynamics on a
growing model biofilm. We aim in particular at unraveling the mechanical contributions from
the solute transport ones. We worked in an Escherichia coli strain over-expressing the conjuga-
tion pilus F, known to promote biofilm formation. We designed a set of 5 micro-fabricated
channels of variable height to grow the biofilm under continuous nutrient flow and explore a
two-orders of magnitude range of shear stress values from a few tenths to a few tens of milli-
pascals. The hydrodynamics of the setup was characterized using experimental and theoretical
data. Mounted on the stage of a microscope, the device enabled continuous monitoring of
channel colonization over the first 20 hours of biofilm development. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Data Availability Statement: All relevant data are
within the paper and its Supporting Information
files. Bacterial communities living attached to surfaces represent a widespread lifestyle of the micro-
bial world[1–4]. In nature, including human hosts, and in artificial environments, these three-
dimensional structures are often immersed in an aqueous fluid in motion and subjected to
hydrodynamic forces[2]. Besides, the advances of microfluidics are making inroads in several
fields of microbiology, providing new tools to investigate processes developing under flow,
such as bacterial biofilm formation. Multiple types of micro-fabricated channels with length
scales ranging from micrometers to centimeters are now used[5–7]. This opens the way to
gaining deeper insight into how hydrodynamics interacts with biofilm development. This Funding: This work was supported by Agence
Nationale de la Recherche - ANR CE02-0001-01
ACToP. The funders had no role in study design,
data collection and analysis, decision to publish, or
preparation of the manuscript. Competing interests: The authors have declared
that no competing interests exist. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 1 / 24 Bacterial biofilm response to hydrodynamics knowledge is currently scattered throughout a large variety of interests, ranging from engi-
neering concerns[8–10] to fundamental biological questions regarding gene regulation by
shear flow[11]. Basically, strong-flow regimes have been studied for their role in biofilm
detachment and deformation, revealing complex effects arising from the interdependence of
the flow strength and the biofilm visco-elastic properties, but essentially showing physical
responses to physical stress[10, 12–16]. In the milder regime of laminar flow with small Rey-
nolds number, which includes shear stress values relevant for many real-life situations—e.g. vasculature of living hosts, quiet river flows, medical devices[17–19]—the spectrum of flow
effects on biofilm development is also broad. It includes initial attachment control[20–23],
quorum sensing regulation[24, 25], morphological changes[20], growth rate modification[26–
29], metabolic switching[28], alteration of visco-elasticity[30, 31], variation of extracellular
matrix production, and possibly gene expression modification[11, 32]. Some of these effects
have clearly been shown to proceed by advection-diffusion mechanisms, e.g. [24] but others
motivate the hypothesis of a biological response to mechanical cues[11, 32]. Indeed, hydrody-
namics simultaneously controls some closely inter-related effects that are very distinct in nature
—namely, molecular transport and mechanical stress. Generally, it is not known whether the
observed phenotypic changes are driven by the alteration of the molecular distribution of a key
compound or by the response of a signaling cascade to mechano-sensing. Data Availability Statement: All relevant data are
within the paper and its Supporting Information
files. While mechano-trans-
duction has long been recognized as an integral part of the cell signaling arsenal in eukaryotes
[33, 34], responses to mechanical forces have received less attention in bacteria, except regarding
cell response to osmotic shocks through the mechano-sensitive ion channel Msc, which is direct-
ly stretched open when the membrane is under turgor pressure[35]. Yet, recently, together with
an increasing interest in micro-organisms on surfaces, attention has emerged towards how bac-
teria respond to mechanical cues, revealing a direct response of attached cells to mechanical
stress applied by shear flow, at the level of gene expression[36–38]. To the best of our knowledge,
such a causal relationship linking mechanical force sensing to gene expression has been clearly
established only at the single-cell level, and not within a three-dimensional biofilm, where it
remains a mere working hypothesis. knowledge is currently scattered throughout a large variety of interests, ranging from engi-
neering concerns[8–10] to fundamental biological questions regarding gene regulation by
shear flow[11]. Basically, strong-flow regimes have been studied for their role in biofilm
detachment and deformation, revealing complex effects arising from the interdependence of
the flow strength and the biofilm visco-elastic properties, but essentially showing physical
responses to physical stress[10, 12–16]. In the milder regime of laminar flow with small Rey-
nolds number, which includes shear stress values relevant for many real-life situations—e.g. vasculature of living hosts, quiet river flows, medical devices[17–19]—the spectrum of flow
effects on biofilm development is also broad. It includes initial attachment control[20–23],
quorum sensing regulation[24, 25], morphological changes[20], growth rate modification[26–
29], metabolic switching[28], alteration of visco-elasticity[30, 31], variation of extracellular
matrix production, and possibly gene expression modification[11, 32]. Some of these effects
have clearly been shown to proceed by advection-diffusion mechanisms, e.g. [24] but others
motivate the hypothesis of a biological response to mechanical cues[11, 32]. Indeed, hydrody-
namics simultaneously controls some closely inter-related effects that are very distinct in nature knowledge is currently scattered throughout a large variety of interests, ranging from engi-
neering concerns[8–10] to fundamental biological questions regarding gene regulation by
shear flow[11]. Basically, strong-flow regimes have been studied for their role in biofilm
detachment and deformation, revealing complex effects arising from the interdependence of
the flow strength and the biofilm visco-elastic properties, but essentially showing physical
responses to physical stress[10, 12–16]. Data Availability Statement: All relevant data are
within the paper and its Supporting Information
files. In the milder regime of laminar flow with small Rey-
nolds number, which includes shear stress values relevant for many real-life situations—e.g. vasculature of living hosts, quiet river flows, medical devices[17–19]—the spectrum of flow
effects on biofilm development is also broad. It includes initial attachment control[20–23],
quorum sensing regulation[24, 25], morphological changes[20], growth rate modification[26–
29], metabolic switching[28], alteration of visco-elasticity[30, 31], variation of extracellular
matrix production, and possibly gene expression modification[11, 32]. Some of these effects
have clearly been shown to proceed by advection-diffusion mechanisms, e.g. [24] but others
motivate the hypothesis of a biological response to mechanical cues[11, 32]. Indeed, hydrody-
namics simultaneously controls some closely inter-related effects that are very distinct in nature knowledge is currently scattered throughout a large variety of interests, ranging from engi-
neering concerns[8–10] to fundamental biological questions regarding gene regulation by
shear flow[11]. Basically, strong-flow regimes have been studied for their role in biofilm
detachment and deformation, revealing complex effects arising from the interdependence of
the flow strength and the biofilm visco-elastic properties, but essentially showing physical
responses to physical stress[10, 12–16]. In the milder regime of laminar flow with small Rey-
nolds number, which includes shear stress values relevant for many real-life situations—e.g. vasculature of living hosts, quiet river flows, medical devices[17–19]—the spectrum of flow
effects on biofilm development is also broad. It includes initial attachment control[20–23],
quorum sensing regulation[24, 25], morphological changes[20], growth rate modification[26–
29], metabolic switching[28], alteration of visco-elasticity[30, 31], variation of extracellular
matrix production, and possibly gene expression modification[11, 32]. Some of these effects
have clearly been shown to proceed by advection-diffusion mechanisms, e.g. [24] but others
motivate the hypothesis of a biological response to mechanical cues[11, 32]. Indeed, hydrody-
namics simultaneously controls some closely inter-related effects that are very distinct in nature
—namely, molecular transport and mechanical stress. Generally, it is not known whether the
observed phenotypic changes are driven by the alteration of the molecular distribution of a key
compound or by the response of a signaling cascade to mechano-sensing. While mechano-trans-
duction has long been recognized as an integral part of the cell signaling arsenal in eukaryotes
[33, 34], responses to mechanical forces have received less attention in bacteria, except regarding
cell response to osmotic shocks through the mechano-sensitive ion channel Msc, which is direct-
ly stretched open when the membrane is under turgor pressure[35]. Bacterial strains and culture conditions The Escherichia coli strain used in this work is TG1-F’ a K12 –MG 1655 derivative carrying the
plasmid F’tet, a gift from the Ghigo lab [39]. All cultures were performed from LB agar plate
colonies grown overnight in LB medium at 37˚C in an agitated Erlenmeyer flask in the pres-
ence of 7.5 μg/ml tetracycline, then diluted in M63B1 minimum medium supplemented with
0.4% glucose to provide an exponentially growing culture with an OD600 equal to 0.2 after a
few hours incubation at 37˚C. Microfabrication and biofilm growth Millifludidic device. We micro-fabricated millifluidic channels 30 mm in length, 1 mm in
width and with heights ranging from 250 μm to 1 mm. A polydimethylsiloxane (PDMS) mix-
ture (RTV615A+B from Momentive) was poured at ambient temperature in a polyvinyl chlo-
ride home-micromachined mold and left to cure at least 3 hours in an oven set at 65˚C. Then,
the recovered templates were drilled for further plugging of adapted connectors and tubings. PDMS templates and glass coverslips were then cleaned using an oxygen plasma cleaner (Har-
rick) and immediately bound together to seal the channels. The last step consisted in adapting
connections: we used stainless steel connectors (0.013" ID and 0.025" OD) and microbore
Tygon tubing (0.020" ID and 0.06" OD) supplied by Phymep (France). The thin metallic con-
nectors accommodate on the flow circuit a bottleneck which prevented upstream colonization. Next the plugged device—usually a set of five channels 250 μm; 350 μm; 500 μm; 750 μm and 1
mm in height, respectively—was fixed on the microscope stage using a customized holder. The
medium was pushed into the channels at a controlled rate using syringe pumps. 5 Biofilm growth. The same amounts—approx. 9.105 cells—of exponentially growing cells
with an optical density at 600 nm equal to 0.2 were injected in the channels and allowed to set-
tle down for 1h30 before starting medium flow (at t = 0) and imaging bacterial development in
the channel. The whole experiment was thermostated at 37˚C. Data Availability Statement: All relevant data are
within the paper and its Supporting Information
files. Thereby, initial coloniza-
tion patterns and three-dimensional growth kinetics could be determined over the whole
range of shear stress values, unveiling a threshold value of shear stress which determined bio-
film settlement. Next, to investigate a potential biofilm response to hydrodynamics at the gene expression
level, we performed a differential transcriptomic analysis of the cells coming from two biofilms
grown under different shear stress regimes. Our results show that mechanical stress precisely determines initial settlement pattern, ori-
enting biofilm development characteristics with notable consequences on expansion kinetics. In contrast, we do not find any signature of mechano-sensing-related signaling upon mechani-
cal stress reinforcement in the two biofilms studied. Instead, we show that, under conditions
where no nutrient depletion occurs, the primary biological response of biofilms to distinct
hydrodynamic conditions consists in a modulation of the low-O2 stress response. Incidentally, PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 2 / 24 Bacterial biofilm response to hydrodynamics our results point out the ability of bacterial biofilms to initiate in low shear stress zones and
strategically spread from these bases towards high shear stress areas—a feature of interest in
the perspective both of controlling beneficial or deleterious adherent communities and of
designing novel fluidic circuits. In conclusion, our results clarify the question of how hydrodynamics impacts biofilm devel-
opment: first, it physically controls initial settlement, next it influences biological response,
involving not mechanotransduction but O2 distribution. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Microscopy Microscope. We used an inverted NIKON TE300 microscope equipped with motorized x,
y, z displacements and shutters. Images were collected using a 20x S plan Fluor objective, NA
0.45 WD 8,2–6,9. Bright field images were collected in direct illumination (no phase). Fluores-
cence acquisitions were performed using an m-cherry dedicated filter configuration (Exc- FF01-
575/25, DM pinkel FF436/514/604-Di01-25x36, Em. FF01-457/530/628-25 Semrock bright Line). Microscope. We used an inverted NIKON TE300 microscope equipped with motorized x,
y, z displacements and shutters. Images were collected using a 20x S plan Fluor objective, NA
0.45 WD 8,2–6,9. Bright field images were collected in direct illumination (no phase). Fluores-
cence acquisitions were performed using an m-cherry dedicated filter configuration (Exc- FF01-
575/25, DM pinkel FF436/514/604-Di01-25x36, Em. FF01-457/530/628-25 Semrock bright Line). Image acquisition. We used a Hamamatsu ORCA-R2 EMCCD camera for time-lapse
acquisitions of 1344x1024 pixels images with 12 bits gray level depth (4096 gray levels) and
captured an xy field of view of 330 μm x430 μm. Bright field and fluorescence images were col-
lected using 10 ms and 40 ms acquisition times, respectively. Unless otherwise stated, biofilms
were imaged for 24 hours at the frequency of 30 frames per hour. Image acquisition. We used a Hamamatsu ORCA-R2 EMCCD camera for time-lapse
acquisitions of 1344x1024 pixels images with 12 bits gray level depth (4096 gray levels) and
captured an xy field of view of 330 μm x430 μm. Bright field and fluorescence images were col-
lected using 10 ms and 40 ms acquisition times, respectively. Unless otherwise stated, biofilms
were imaged for 24 hours at the frequency of 30 frames per hour. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 3 / 24 Bacterial biofilm response to hydrodynamics Image analysis. Image intensity per pixel averaged on defined regions of interest (ROIs)
was collected using the NIKON proprietary software NIS. The data sheets edited by NIS were
next exported to Matlab for further analysis of the biofilm development kinetics and growth
parameters determination. Signal calibration. To quantitatively monitor biofilm growth, we used the microscope as
a microphotometer and defined a microscopic absorbance Aμ = ln (I0/I), where I0 is the inten-
sity (averaged gray level per pixel) of images recorded on a channel filled with water and I the
intensity of the channel containing the growing biofilm, the presence of which attenuates inci-
dent light transmission. Microscopy The attenuation was related to biomass in the channel by analogy with
the empirical Beer-Lambert law stating that light absorbance by a material is directly propor-
tional to the sample thickness and concentration. We verified this by growing a series of 10
identical biofilms in parallel in 1 mm-height channels under 1 ml/h medium flow rate. At dif-
ferent time points along the biofilm growth, biofilm growth was stopped by arresting nutrient
flow and immediately extracting the biofilm from the channel using repeated air jet pulses. The extracted material was then entirely resuspended in 300 μL of minimum medium by gen-
tle pipetting. Next, the concentrated suspension was diluted in minimal medium for optical
density (OD) measurements in a spectrophotomer cuvette, and biomass was evaluated consid-
ering an OD-specific concentration of E. coli cells in a suspension (i.e. the number of cells per
milliliter at an OD of 1 measured at 600 nm) equal to 5.108 cells/mL. We then obtained the
relation between the amount of cells in the channel and the microscopic absorbance, Aμ. For
further evaluation of local biomass, we converted it into a relation linking Aμ and a cell surfacic
concentration, CS, defined as the number of cells settling over a 1 mm2 channel surface: CS =
3x107 Aμ. The details given in supplementary information (S1 Fig) also show that, as in the
macroscopic version of the Beer-Lambert law, the absorbance-biomass relation deviates from
the linear regime at high concentrations. In the conditions of I0 used for biofilm growth moni-
toring, the biomass detection signal started to level off for microscopic absorbance values
equal to 0.7. Such nonlinearities were accounted for in the growth curve analysis. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Velocity field measurement and calculation Growth medium supplemented with red (580/605) fluorescent particles 1 μm in diameter
(Molec. Probes, F-8821) was pushed into the channel at a defined flow rate. Then, z-stack
images were recorded using an acquisition time (tacq) of 40 ms, which caused the particles to
appear on the images as linear trails, the length of which yielded the local velocity v(x,y,z) in
the channel through v(x,y,z) = l(x,y,z)/tacq, where l(x,y,z) is the length of the trail (once the
bead diameter is subtracted). The experimental velocity fields were derived from the collection
of trail lengths in all available (x,y,z)-positions in the z-stacks (S2 Fig). Besides, we expressed the theoretical velocity field using the formula for a steady viscous
flow of an incompressible fluid in a rectangular channel at low Reynolds number[40, 41]. This
velocity field satisfies the Stokes equation with non-slip boundary conditions on the channel
walls (at y = 0, y = w the channel width, z = 0 and z = h the channel height, for all x), and with
an imposed pressure gradient dp/dx along the x direction. It reads39: ¼ y
w 1 y
w
þ z
h 1 z
h
X1
n¼0 ð 1Þ
n
2
ð2n þ 1Þp
3 cosh pn y w
2
cosh pn
w
2
cos pn z h
2
þ cosh qn z h
2
cosh qn
h
2
cos qn y w
2
"
#
; ð1Þ with pn ¼ ð2nþ1Þp
h
, qn ¼ ð2nþ1Þp
w
and v1 ¼ v w
2 ; h
2
¼ 1
8Z
dp
dx
w2h2
w2þh2, where η is the dynamic viscosity of the
fluid. with pn ¼ ð2nþ1Þp
h
, qn ¼ ð2nþ1Þp
w
and v1 ¼ v w
2 ; h
2
¼ 1
8Z
dp
dx
w2h2
w2þh2, where η is the dynamic viscosity of the
fluid. RNA preparation Total RNA was prepared from exponentially growing (OD600 0.3–0.5)—called sample E—
and saturated (OD600 2.6–4.5)—called sample S—liquid cultures in M63B1 medium supple-
mented with 0.4% of glucose, and from biofilms grown in micro-channels under the strongest
confinement considered, i.e. 250 μm-height (sample H) and under the lowest confinement
considered, 1 mm-height (sample L). Biofilms were extracted from the channels by repeated
air jet pulses and the cells immediately resuspended at 4˚C as concentrated viscous aliquots of
200–300 μl. The OD was measured and an adequate volume was taken and centrifuged to get a
pellet of approx. 109 cells. All RNA was then isolated and purified with RiboPure-Bacteria Kit
(Ambion, Life Technologies). Sample quality was checked and quantified by gel electrophore-
sis using Bioanalyser (Agilent); about 10 μg total RNA per sample was obtained. It was imme-
diately stored at -80˚C for time periods of maximum 5 weeks, prior to mRNA purification and
RNA-Seq analysis. All samples were run in triplicates. RNA sequencing and data analysis Sequencing was carried out using an Illumina HiSeq platform via a commercial service (Euro-
fins MWG GmbH, Ebersberg, Germany). Mapping of reads to reference sequences was per-
formed using BWA-MEM (version 0.7.12-r1039, http://bio-bwa.sourceforge.net/). Raw read
counts were created using featureCounts[42]. A Trimmed Mean of M-values normalization
and differential expression analysis was performed using the edgeR package[43, 44]. Among
all the twelve triplicated samples, one, which exhibited unrelated data, was removed from the
analysis. Velocity field measurement and calculation PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 4 / 24 Bacterial biofilm response to hydrodynamics The associated volumetric flow rate Q, which can be obtained by integrating the velocity
field over a transverse section of the channel, reads: The associated volumetric flow rate Q, which can be obtained by integrating the velocity
field over a transverse section of the channel, reads: Q ¼ 4whv1
1
3 X
1
n¼0
2
ð2n þ 1Þp
5 h
w tanhðpn
w
2Þ þ w
h tanhðqn
h
2Þ
(
)
: xperimentally-measured velocity fields were adjusted to these theoretical expressions The experimentally-measured velocity fields were adjusted to these theoretical expressions
using Matlab’s nonlinear least-square fitting algorithms (lsqcurvefit and nlinfit). We checked
that the infinite series in the formulas for v(y,z) and Q converge quite fast, as can be guessed by
the 1/(2n+1)3 and 1/(2n+1)5 dependences of the summed terms. In practice, the results of our
fits varied by less than 0.1% upon cutting the series at n = 3 versus n = 2, and we also checked
that no larger change occurred in the fitted parameters when including terms up to n = 10. Here, we always used results obtained by cutting the series at n = 3. The shear stress distribu-
tion was obtained by differentiating these velocity fields. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Oxygen measurement Dissolved O2 was measured by quenching a Ruthenium complex (Ruthenium–tris(4,7– diphe-
nyl–1,10-phenanthroline) dichloride (Ru(dpp)); Fluka) encapsulated in micelles of (1,2–Dipal-
mitoyl–sn–Glycero–3–Phosphoethanolamine–N[Methoxy(Poly–ethylene glycol)–2000]
(DMPC–PEG2000) phospholipids; Avanti. The encapsulation of the Ru(dpp) complex in the
micelles[45] yields it biocompatible while allowing to exhibit a linear fluorescence response to
the oxygen concentration. This response follows a Stern-Volmer plot that we further used to
convert the fluorescence intensity into oxygen concentration[46]. Ru–micelles were added to
the channels with or without biofilm at a concentration of 8 μM. Fluorescence images were
collected using a 60x plan Apo Oil objective, NA 1.4 WD 0.21, and using an FITC dedicated PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 5 / 24 Bacterial biofilm response to hydrodynamics filter configuration (FF01-482/35-25 FF506-DiO3-25x36 536/40-25). Images were acquired
using 100 ms acquisition time. In order to get the fluorescence intensity value at 20% oxygen, a
calibration experiment was performed by measuring the fluorescence of a solution saturated
with 20% oxygen by vigorous shaking for several minutes. Fluid dynamics impacts initial colonization pattern and development
kinetics To initiate biofilm growth in the five channels mounted in parallel, we inoculated the same
amount of bacteria (approx. 9.105 cells) in each. After 1h30, growth medium flow was started
and colonization was monitored by time-lapse video microscopy. Due to bacteria sedimenta-
tion during incubation, initial colonization occurred only on the bottom glass slide of the
channel. Our first qualitative observations revealed two different development patterns. The condi-
tions applied in the 3 channels imposing weakest confinement (height between 1 mm and
500 μm)—corresponding to the lowest shear stress regime—promoted a uniform development
of the biofilm over the bottom surface of the channel. In contrast, in the geometries imposing
higher shear stress and confinement, i.e. in the 250- and 350-μm-height channels, the biofilm
developed according to an advancing-front mode, progressing from the edge towards the cen-
ter of the channel (Fig 2A, S1–S5 videos). To take into account the spatial distribution of the fluid dynamics within a given channel,
we defined a set of ten rectangular regions of interest (ROIs), successively drawn along the y-
axis of the field of view starting at the right edge of the image (see Fig 2B). Each ROI captured
a channel segment characterized by a mean bottom shear stress which increased from the edge
(ROI1) to the center of the channel (ROI10), with partially overlapping shear stress ranges in
different channels (Fig 2C). Using calibration information (S1 Fig), the image stacks collected
in each channel could be used to infer biomass expansion kinetics. Series of ten curves (one
per ROI) reporting the time evolution of colonization of channel regions under different local
hydrodynamic conditions were obtained. The 10-ROI-curve series exhibited either a bundle of
curves closely grouped together on the time axis or a series of regularly spaced curves, consis-
tently reflecting the two distinct—uniform and advancing-front—growth modes (Fig 2D). Focusing on the initial period of colonization, i.e. the first 10 hours, we found that the 50
ROIs defined through the 5 channels could be sorted in two categories: those where bacteria
could steadily attach to the surface within the first ten hours and directly initiate biofilm for-
mation, and those where no initial attachment was observed. In a millifluidic channel, cells are exposed to a distribution of different
shear stress values https://doi.org/10.1371/journal.pone.0175197.g001 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 6 / 24 Bacterial biofilm response to hydrodynamics the limiting nutrient—was always supplied in excess, so that no nutrient depletion occurred
(S1 File). the limiting nutrient—was always supplied in excess, so that no nutrient depletion occurred
(S1 File). In a millifluidic channel, cells are exposed to a distribution of different
shear stress values To capture and understand the impact of fluid dynamics on biofilm formation features, we
microfabricated a set of five channels with the same width, w (1 mm), and length (3 cm), but
differing by their height, h, ranging from 250 μm to 1 mm. In order to clarify the hydrodynamic properties of our setup, we calculated the shear stress
distribution profile in each channel, using the theoretical approach of O’Brien[40] to take into
account their low-aspect ratio geometries, i.e. wh (see S3 Fig and Materials and Methods). Fig 1 shows that the 5 channels, under a flow rate, Q, of 1 ml/h (as in the rest of our work),
exhibited shear stress values σ at the channel bottom (z = 0) spanning almost two orders of
magnitude, from 0.42 to 31.5 mPa, depending on the considered channel and on the position
with respect to the edge of the channel. The fluid velocity fields calculated using this theoretical
framework were consistent with those derived from the experiments where we measured the
length of fluorescent particle trails (S2 and S3 Figs). This agreement enabled us to derive the
actual value of σ at any point of any channel knowing h, w and Q. The 1 ml/h flow rate was
chosen to achieve biofilm installation within a few hours, while applying shear stresses relevant
to physiological and natural situations[17–19]. This flow rate also guaranteed that glucose— Fig 1. Shear stress significantly varies across the width of a millifluidic channel. (A) Channel blueprint. (B) Bottom shear stress values, obtained by
differentiation of the calculated velocity fields, are given for the 5 PDMS channels having a 30 mm length, 1 mm width (y axis) and 250 μm (red); 350 μm
(orange); 500 μm (green); 750 μm (light blue); 1 mm (dark blue) height, under a flow rate of 1 ml/h. https://doi.org/10.1371/journal.pone.0175197.g001 Fig 1. Shear stress significantly varies across the width of a millifluidic channel. (A) Channel blueprint. (B) Bottom shear stress values, obtained by
differentiation of the calculated velocity fields, are given for the 5 PDMS channels having a 30 mm length, 1 mm width (y axis) and 250 μm (red); 350 μm
(orange); 500 μm (green); 750 μm (light blue); 1 mm (dark blue) height, under a flow rate of 1 ml/h. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 (A) Surface pattern of biofilm growing in the
uniform growth mode (upper panel) and in the advancing-front growth mode (lower panel), yellow arrows indicate biofilm expansion directions; bright field
picture taken using a 20x objective after 12 hours of continuous growth in M63B1 glucose medium in a 1 mm-height channel (uniform mode, upper panel) and
a 250 μm-height channel (advancing-front mode, lower panel). The right edge of the picture coincides with the right edge of the channel, and a 330x440 μm2
field is imaged. (B) Images are divided in 10 adjacent ROIs of 40 μm width, numbered from 1 (darker shade) to 10 (lighter shade); ROI1 is the channel edge
ROI and ROI10 is a central ROI, located at 400 μm from the channel edge. (C) Bottom shear stress ranges overlapping between the 5 channels of the setup
with channel heights on the left and aspect ratios on the right. Same channel color code as in Fig 1. (D) Series of growth curves derived from time-lapse image
analysis. The microscopic absorbance, Aμ = ln(I0/I), reporting the local biomass, is plotted as a function of time under continuous nutrient flow. Data points are
represented in color for 10 ROIs per channel (one channel per graph) using the same color code as in Fig 1, and shades from dark to light coding for ROI1 to
ROI10. Plot of a representative experiment of at least three (see data statistical dispersion in S1 Table). (E) Biofilm initiation is subjected to a 10 mPa shear
stress threshold Colonized ROIs (closed symbols) and non-colonized ones (open symbols) as observed in the 5 channels (same color code as in Fig 1) Fig 2. Quantitative monitoring of biofilm growth reveals shear stress impact on biofilm development. (A) Su ofilm growth reveals shear stress impact on biofilm development. (A) Surface pattern of biofilm growing in the
d i th
d
i
f
t
th
d (l
l)
ll
i di
t bi fil
i
di
ti
b i ht fi ld Fig 2. Quantitative monitoring of biofilm growth reveals shear stress impact on biofilm development. Bacterial biofilm response to hydrodynamics Fig 2. Quantitative monitoring of biofilm growth reveals shear stress impact on biofilm development. (A) Surface pattern of biofilm growing in the
uniform growth mode (upper panel) and in the advancing-front growth mode (lower panel), yellow arrows indicate biofilm expansion directions; bright field
picture taken using a 20x objective after 12 hours of continuous growth in M63B1 glucose medium in a 1 mm-height channel (uniform mode, upper panel) and
a 250 μm-height channel (advancing-front mode, lower panel). The right edge of the picture coincides with the right edge of the channel, and a 330x440 μm2
field is imaged. (B) Images are divided in 10 adjacent ROIs of 40 μm width, numbered from 1 (darker shade) to 10 (lighter shade); ROI1 is the channel edge
ROI and ROI10 is a central ROI, located at 400 μm from the channel edge. (C) Bottom shear stress ranges overlapping between the 5 channels of the setup
with channel heights on the left and aspect ratios on the right. Same channel color code as in Fig 1. (D) Series of growth curves derived from time-lapse image
analysis. The microscopic absorbance, Aμ = ln(I0/I), reporting the local biomass, is plotted as a function of time under continuous nutrient flow. Data points are
represented in color for 10 ROIs per channel (one channel per graph) using the same color code as in Fig 1, and shades from dark to light coding for ROI1 to
ROI10. Plot of a representative experiment of at least three (see data statistical dispersion in S1 Table). (E) Biofilm initiation is subjected to a 10 mPa shear
stress threshold. Colonized ROIs (closed symbols) and non-colonized ones (open symbols), as observed in the 5 channels (same color code as in Fig 1)
during the initial phase of biofilm development, are ordered on a shear stress range, evidencing the 10 mPa transition (arrow) between a shear stress which
permits initial adhesion and a shear stress which does not. h
//d i
/10 1371/j
l
0175197 002 Fig 2. Quantitative monitoring of biofilm growth reveals shear stress impact on biofilm development. Fluid dynamics impacts initial colonization pattern and development
kinetics In the latter regions, space colo-
nization took place through later expansion of the biofilm initiated in a low shear stress region
of the channel near the edges, towards regions of higher shear stress values (see S4 and S5 vid-
eos). Characterizing each region by its mean bottom shear stress, we found a threshold shear
stress value of 11±2 mPa, above which no direct initiation of biofilm could occur on the surface
(Fig 2E and S5 Fig). This initial obstacle to settlement favored the advancing-front growth mode for biofilms
growing in the highest-confinement channels. Biofilm then expanded from the channel edges,
where shear stress values are initially below 10 mPa. By contrast, uniform initial adhesion pro-
moted uniform growth in the lowest-confinement channels featuring shear stress values below
10mPa throughout the channel. To find out how these two types of biofilms functionally differed, we determined specific
growth parameters, namely the growth rate and the lag time, from the time evolution of the
biomass, measured through the microscopic absorbance Aμ = ln (I0/I) (see Fig 3 for an exam-
ple). The measured absorbance was first corrected by the experimentally-measured relation
between microscopic absorbance and concentration (see Fig 3 and calibration information in
S1 Fig). This correction frees our analysis from the slight nonlinearities present even at low PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 7 / 24 (A) Surface pattern of biofilm growing in the
uniform growth mode (upper panel) and in the advancing-front growth mode (lower panel), yellow arrows indicate biofilm expansion directions; bright field
picture taken using a 20x objective after 12 hours of continuous growth in M63B1 glucose medium in a 1 mm-height channel (uniform mode, upper panel) and
a 250 μm-height channel (advancing-front mode, lower panel). The right edge of the picture coincides with the right edge of the channel, and a 330x440 μm2
field is imaged. (B) Images are divided in 10 adjacent ROIs of 40 μm width, numbered from 1 (darker shade) to 10 (lighter shade); ROI1 is the channel edge
ROI and ROI10 is a central ROI, located at 400 μm from the channel edge. (C) Bottom shear stress ranges overlapping between the 5 channels of the setup
with channel heights on the left and aspect ratios on the right. Same channel color code as in Fig 1. (D) Series of growth curves derived from time-lapse image
analysis. The microscopic absorbance, Aμ = ln(I0/I), reporting the local biomass, is plotted as a function of time under continuous nutrient flow. Data points are
represented in color for 10 ROIs per channel (one channel per graph) using the same color code as in Fig 1, and shades from dark to light coding for ROI1 to
ROI10. Plot of a representative experiment of at least three (see data statistical dispersion in S1 Table). (E) Biofilm initiation is subjected to a 10 mPa shear
stress threshold. Colonized ROIs (closed symbols) and non-colonized ones (open symbols), as observed in the 5 channels (same color code as in Fig 1)
during the initial phase of biofilm development, are ordered on a shear stress range, evidencing the 10 mPa transition (arrow) between a shear stress which
permits initial adhesion and a shear stress which does not. https://doi.org/10.1371/journal.pone.0175197.g002 absorbance in this relation. We then performed exponential adjustments of the corrected
absorbance curves f(t) (Fig 3), yielding the growth rate μ: f ðtÞ ¼ f0emt We also considered the time δ at which the biomass reached a corrected absorbance value
of 0.02, which provided an effective lag time for the colonization process (Fig 3). This PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 8 / 24 Bacterial biofilm response to hydrodynamics Fig 3. Exponential adjustment and derivation of growth parameters. A typical experimental curve
showing microscopic absorbance (blue dots and left y axis) is represented together with the curve corrected
by the microscopic absorbance-concentration relation in S1 Fig (red dots and right y axis) and the exponential
adjustment (black line) giving the growth rate μ. The lag time δ is defined as the time where the corrected
absorbance hits 0.02 (dashed line). Fig 3. Exponential adjustment and derivation of growth parameters. A typical experimental curve
showing microscopic absorbance (blue dots and left y axis) is represented together with the curve corrected
by the microscopic absorbance-concentration relation in S1 Fig (red dots and right y axis) and the exponential
adjustment (black line) giving the growth rate μ. The lag time δ is defined as the time where the corrected
absorbance hits 0.02 (dashed line). https://doi.org/10.1371/journal.pone.0175197.g003 https://doi.org/10.1371/journal.pone.0175197.g003 threshold was chosen to be above experimental noise while remaining small, thus indicating
growth onset. Using this formalism, we first examined the case of mild shear stress regions (σ < 10 mPa). The results in Fig 4A show that the growth rate μ was constant both across the different posi-
tions in a given channel and across the different channels, showing that biofilm expansion rate
was not sensitive to physical stress in these mild conditions. Besides, the apparent lag time δ
increased with shear stress (correlation coefficient 0.55, p-value 0.001), indicating a shear
stress-induced delay to initial cell docking (Fig 4B). Fig 4. Below 10 mPa, shear stress does not affect biofilm growth rate, but impacts apparent lag time. (A) Biofilm growth rate, μ (as derived from the exponential adjustment, see Fig 3) as a function of bottom
shear stress. (B) The apparent lag time, δ, increases as a function of shear stress; experimental data (solid
colored dots) can be adjusted using an exponential law (grey line). Data were collected from biofilm growing in
the low shear stress regime, i.e. at σ <10 mPa. Data are represented using the same channel color code as in
Fig 1. Means and SDs over two positions are represented. Plot of a representative experiment of at least three
(see data statistical dispersion in S1 Table). https://doi.org/10.1371/journal.pone.0175197.g004 Fig 4. Below 10 mPa, shear stress does not affect biofilm growth rate, but impacts apparent lag time. Fig 4. Below 10 mPa, shear stress does not affect biofilm growth rate, but impacts apparent lag time. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 (A) Biofilm growth rate, μ (as derived from the exponential adjustment, see Fig 3) as a function of bottom
shear stress. (B) The apparent lag time, δ, increases as a function of shear stress; experimental data (solid
colored dots) can be adjusted using an exponential law (grey line). Data were collected from biofilm growing in
the low shear stress regime, i.e. at σ <10 mPa. Data are represented using the same channel color code as in
Fig 1. Means and SDs over two positions are represented. Plot of a representative experiment of at least three
(see data statistical dispersion in S1 Table). https://doi org/10 1371/journal pone 0175197 g004 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 9 / 24 Bacterial biofilm response to hydrodynamics Fig 5. Local growth rate and lag time in the advancing-front growth mode characterize the biofilm
spatial spreading. Biofilm growth rate, μ (A) as derived from the exponential adjustment, (see Fig 3) and
apparent lag time δ (B), as a function of the lateral location in the channels in the high bottom shear stress
regime (> 10 mPa)—the 250 μm-height one (red dots) and the 350 μm-height one (orange dots). The slope of
the lag time linear adjustment (grey line) provides the front propagation velocity. Means and SDs over two
positions are represented. Plot of a representative experiment of at least three (see data statistical dispersion
in S1 Table). htt
//d i
/10 1371/j
l
0175197 005 Fig 5. Local growth rate and lag time in the advancing-front growth mode characterize the biofilm
spatial spreading. Biofilm growth rate, μ (A) as derived from the exponential adjustment, (see Fig 3) and
apparent lag time δ (B), as a function of the lateral location in the channels in the high bottom shear stress
regime (> 10 mPa)—the 250 μm-height one (red dots) and the 350 μm-height one (orange dots). The slope of
the lag time linear adjustment (grey line) provides the front propagation velocity. Means and SDs over two
positions are represented. Plot of a representative experiment of at least three (see data statistical dispersion
in S1 Table). https://doi.org/10.1371/journal.pone.0175197.g005 Then, we explored the growth traits of the biofilms that developed under bottom shear
stress values higher than 10 mPa, i.e. grown in the 250 μm- and 350 μm-height channels. Due
to the advancing-front growth mode associated with this shear stress range, the expansion rate
and lag time contained different information. Indeed, the increase of the biomass in a given
ROI resulted from the material densification and vertical growth—as under mild shear stress
—but also from a lateral directional input of mature material progressing from the edge. These
combined contributions were indistinctly reported by the rate μ. In addition, in this growth
mode, the apparent lag time δ(Ri), associated with each ROIi gave the time the front took to
reach the ROIi position, yielding the front velocity. Then, for all the colonized ROIs in the two
high shear stress channels, we plotted μ and δ as a function of the distance y separating the
right boundary of the considered ROI from the channel right edge (Fig 5). In both channels,
we observed that lag times increased linearly with distance y, indicating a constant front veloc-
ity. In addition, both channels exhibited similar front velocities, given by the inverse of the
slope of δ = f(y), equal to 529±10 μm/day and 513±10 μm/day for the 250 μm and 350 μm–
height channels, respectively. The front progression delay between the two channels (0.22
±0.05 day) was consistent with the lag time difference (0.16±0.05 day) expected from the shear
stress values in their edge ROIs (4.3 mPa and 9.9 mPa in the 250 μm-height and 350 μm-height
channels, respectively (Fig 4)). Meanwhile, the growth rate, μ, increased with the distance to the edge of the channel up to
y = 200 μm where it reached a maximal value (Fig 5). This indicates that, as the front pushed
ahead, the biofilm also extended vertically. Both channels, despite differences in their confine-
ment level (and thus in the shear stress applied to the developing material), exhibited similar
colonization rates at the same location in the channel. Interestingly, higher growth rates were measured in the biofilm growing under the advanc-
ing-front mode than in the uniform one (S2 Table), indicating a higher colonizing efficiency
of the advancing growth mode in the phase of expansion of the biofilm. These results show that the physical forces applied by fluid flow have a drastic impact on
biofilm initiation on the surface, which indirectly impacts further biofilm colonization effi-
ciency. However, they have no direct influence on biofilm intrinsic growth rate. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Bacterial biofilm response to hydrodynamics Fig 6. The velocity field evolves as the biofilm grows in the channel. (A) Effective height of a 1 mm-total-height channel in the presence of growing
biofilm. Main panel: Adjusted effective height h versus time t of biofilm growth. Error bars represent 95% confidence intervals on h, obtained from the
adjustment. Insets: examples of adjustment of the velocity field. Dots: experimentally-measured velocities v at various positions (y, z) across the channel. Data was collected for all z within a narrow band of y (width Δy = 75 μm << w) located at the middle of the channel. Solid red curve: adjustment to the
theoretical expression of the velocity field of a viscous fluid in a rectangular channel (Eq 1), plotted with y in the middle of the Δy-wide band. Dashed red
curves: idem for y at each edge of the Δy-wide band. In addition to the effective height h, the volumetric flow rate Q was adjusted (through—η dp/dx), as in the
absence of biofilm (S3 Fig), yielding Q = 0.85 mL/h, consistent with the adjusted value Q = 0.83 mL/h obtained in the biofilm-free case (S3 Fig). (B) Apparent
size reduction in a 250 μm-height channel colonized by a biofilm after 15h growth. Dots: experimentally-measured velocities v at various positions (y, z)
across the channel. Surface: adjustment to the theoretical expression of the velocity field of a viscous fluid in a rectangular channel (Eq 1). The color scale
denotes velocities (see v axis). Black lines: distance between the experimentally-measured velocities and the adjusted values at the same location. Both the
width w and the effective position y0 of the no-slip boundary condition in the y direction were adjusted, yielding w = 0.57 mm and y0 = 0.23 mm. The volumetric
flow rate Q was set to its experimentally-imposed nominal value 1 mL/h, which yields a good adjustment in the biofilm-free case (S3 Fig). The coefficient of
determination of the fit is R2 = 0.92. Picture: Growing biofilm snapshot showing the fluid (gray)/biofilm (black) interface matching the boundaries given by the
fit. Fig 6. The velocity field evolves as the biofilm grows in the channel. (A) Effective height of a 1 mm-total-height channel in the presence of growing
biofilm. Main panel: Adjusted effective height h versus time t of biofilm growth. Error bars represent 95% confidence intervals on h, obtained from the
adjustment. Insets: examples of adjustment of the velocity field. Dots: experimentally-measured velocities v at various positions (y, z) across the channel. Data was collected for all z within a narrow band of y (width Δy = 75 μm << w) located at the middle of the channel. Solid red curve: adjustment to the
theoretical expression of the velocity field of a viscous fluid in a rectangular channel (Eq 1), plotted with y in the middle of the Δy-wide band. Dashed red
curves: idem for y at each edge of the Δy-wide band. In addition to the effective height h, the volumetric flow rate Q was adjusted (through—η dp/dx), as in the
absence of biofilm (S3 Fig), yielding Q = 0.85 mL/h, consistent with the adjusted value Q = 0.83 mL/h obtained in the biofilm-free case (S3 Fig). (B) Apparent
size reduction in a 250 μm-height channel colonized by a biofilm after 15h growth. Dots: experimentally-measured velocities v at various positions (y, z)
across the channel. Surface: adjustment to the theoretical expression of the velocity field of a viscous fluid in a rectangular channel (Eq 1). The color scale
denotes velocities (see v axis). Black lines: distance between the experimentally-measured velocities and the adjusted values at the same location. Both the
width w and the effective position y0 of the no-slip boundary condition in the y direction were adjusted, yielding w = 0.57 mm and y0 = 0.23 mm. The volumetric
flow rate Q was set to its experimentally-imposed nominal value 1 mL/h, which yields a good adjustment in the biofilm-free case (S3 Fig). The coefficient of
determination of the fit is R2 = 0.92. Picture: Growing biofilm snapshot showing the fluid (gray)/biofilm (black) interface matching the boundaries given by the
fit. https://doi.org/10.1371/journal.pone.0175197.g006 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 10 / 24 Bacterial biofilm response to hydrodynamics From the velocity field characteristics, we calculated that in the 1 mm-height channel, the
maximal bottom shear stress evolved from 2.67 mPa in the initial phase of growth (when bio-
film thickness is negligible), to 3.02 mPa after 20 hours of growth (when a 70 μm thick biofilm
layer has settled). Hence, the physical stress applied to the biofilm interface was not strongly
affected (+13%). In contrast, in the 250 μm-height channel, the maximal bottom shear stress
shifted from 31,5 mPa in the initial phase to 72,3 mPa after 15 h (when biofilm front has
advanced 250 μm from the edge of the channel), demonstrating a significant increase of the bot-
tom shear stress at the center of the channel. Yet, considering not this maximal bottom shear
stress but the one at the biofilm advancing front, we notice that, within a 6 μm-wide strip
adjoining the biofilm front, shear stress has values below 10 mPa. This region of low shear stress,
resulting from the reshaping of the velocity field by biofilm growth, enables biofilm expansion
in spaces that initially could not be colonized through direct adhesion to the channel bottom. Biofilms formed under different hydrodynamic regimes exhibit exquisitely
distinct transcriptomes, pointing at the impact of O2 distribution To investigate biological functions potentially associated with the uniform and advancing-
front growth modes induced by the two shear stress regimes, we performed a whole transcrip-
tome analysis of the two types of biofilm. We focused on samples extracted from the 250 μm-
height channel, featuring the highest confinement and highest shear stress (sample H) and
from the 1 mm-height channel, featuring the lowest confinement and lowest shear stress (sam-
ple L). The biofilms were extracted from the channels for RNA preparation in their maximal
growth phase (see Materials and Methods). In addition, to confront the results with existing
knowledge about biofilm-specific gene expression, we also studied cells harvested from plank-
tonic exponentially growing (sample E) and saturated (sample S) cultures. Analyzing the transcriptome by principal component analysis showed that all the condi-
tions could be clustered independently, with H and L biofilms appearing in neighboring
regions of the multiscaling plot (Fig 7A). One of the sample H triplicates, which was inexplica-
bly apart from the other samples (data not shown), was not taken into account in the differen-
tial expression analysis. Considering the pairwise distances between the four samples in
number of genes exhibiting significantly differential expressions, i.e. a False Discovery Rate
(FDR) <0.01, we found that 25 genes discriminated H and L samples, while the most different
physiology was that of cells from saturated cultures (more than 2000 affected genes). Compara-
tively, only a few hundred genes were differentially expressed between exponentially growing
planktonic cells and biofilm-dwelling cells, suggesting that cell populations of biofilms grown
under continuous nutrient flow share more traits with exponentially growing cells than with
stationary phase cells. Further examination of the 25 genes differentially expressed in sample L versus sample H
revealed that 19 were more expressed at low than at high shear stress (Table 1). Interestingly,
10 were associated with anaerobic metabolism[47] and 4 were linked to acidic conditions resis-
tance. Besides, the expression levels of most of these genes were lower in samples E than in H
(where they are lower than in L) (Fig 7B). In good agreement with this finding, these 14 genes
have already been identified (or related to) genes involved in biofilm formation[48, 49]. Con-
sistently, cytochrome oxidase genes were also differently expressed in H and L (S4 Fig). PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Biofilm growth modulates hydrodynamics Next, we wanted to examine to what extent biofilm growth affects the hydrodynamics in the
channels. To this end, we first injected fluorescent beads in the fluid flow of the 1 mm-height
channel while biofilm was growing. z-stack images were recorded at various stages of develop-
ment to collect particle trails and derive the flow velocity fields. The data were adjusted using
the theoretical formula of O’Brien (see Materials and Methods), leaving the effective channel
height, h, as a free parameter derived from the fit. We plotted this effective height as a function
of the biofilm growth time (Fig 6A). A similar approach was used to analyze the velocity field
in the 250 μm-height channel in which biofilm had grown for 15 h, but this time, we took the
channel width, w, as an adjustable parameter, in order to account for the advancing-front
growth mode of the biofilm (Fig 6B). The quality of the adjustments of the flow velocity fields
confirmed that, in the presence of the biofilm, flow characteristics corresponded to a con-
served laminar flow in a rectangular channel, with a size reduced by an amount corresponding
to the thickness of the biofilm. Interestingly, the extrapolation to zero velocity corresponded to the biofilm/fluid interface,
indicating that the fluid flow did not penetrate into the biofilm the surface of which thus
defined the flow motion boundary. 11 / 24 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Bacterial biofilm response to hydrodynamics Fig 7. Biofilms under distinct fluid flow regimes exhibit exquisitely different gene expression. (A) Principal component analysis and clustering of
genes differentially expressed in cells grown under different conditions: L (lower shear stress and lower confinement regime, i.e. 1 mm-height channel), H
(higher shear stress and higher confinement, i.e. 250 μm-height channel), E (planktonic cells in exponential phase), S (planktonic cells in stationary phase). The number of genes with a False Discovery Rate < 0.01 in our differential expression analysis, is indicated above arrows. (B) 3-component plot representing
ln(L/E) vs. ln(L/H) where L, E and H designate mean expression level in samples L, E and H respectively. Each point corresponds to a gene. Red: genes
related to anaerobic metabolism; blue: genes related to acid resistance; green: genes related to sulfate metabolism; black: others genes. All red and blue
genes (except hypD) fall in the purple zone: they have a lower expression in samples E and a higher expression in samples L, expression in samples H being
intermediate. low regimes exhibit exquisitely different gene expression. (A) Principal component analysis and clustering of
d
diff
di i
L (l
h
d l
fi
i
i
h i h
h
l) H Fig 7. Biofilms under distinct fluid flow regimes exhibit exquisitely different gene expression. (A) Principal component analysis and clustering of
genes differentially expressed in cells grown under different conditions: L (lower shear stress and lower confinement regime, i.e. 1 mm-height channel), H
(higher shear stress and higher confinement, i.e. 250 μm-height channel), E (planktonic cells in exponential phase), S (planktonic cells in stationary phase). The number of genes with a False Discovery Rate < 0.01 in our differential expression analysis, is indicated above arrows. (B) 3-component plot representing
ln(L/E) vs. ln(L/H) where L, E and H designate mean expression level in samples L, E and H respectively. Each point corresponds to a gene. Red: genes
related to anaerobic metabolism; blue: genes related to acid resistance; green: genes related to sulfate metabolism; black: others genes. All red and blue
genes (except hypD) fall in the purple zone: they have a lower expression in samples E and a higher expression in samples L, expression in samples H being
intermediate. https://doi.org/10.1371/journal.pone.0175197.g007 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Biofilms formed under different hydrodynamic regimes exhibit exquisitely
distinct transcriptomes, pointing at the impact of O2 distribution Besides, 6 genes were down-regulated by a factor 2.5 to 5 at low versus high fluid dynamics
among which 3 were related to sulfate metabolism (Table 1). All together, these results show that beyond the biofilm growth traits and developmental
pattern, the major impact of the flow hydrodynamics on biofilm physiology regards aerobiosis
regulation, showing enhanced low O2-stress level at low fluid flow. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 12 / 24 Biofilms under flow in a millifluidic channel grow under a low partial
pressure of oxygen Anaerobic metabolism genes (Bold), acid resistance genes (Italic), Sulfate metabolism genes
(Underlined). Table 1. Genes most affected in expression in biofilms under flow: low fluid dynamical regime (L) ver-
sus high fluid dynamical regime (H). Second column is the ratio between mean normalized transcriptional
expressions. Anaerobic metabolism genes (Bold), acid resistance genes (Italic), Sulfate metabolism genes
(Underlined). Genes with F.D.R. < 0.01
L/H(a)
yhjX, pyruvate-inducible inner membrane protein putative transporter
14,70
hycB, hydrogenase 3 Fe-S subunit
11,44
hycC, hydrogenase 3 membrane subunit
7,18
yhiM, acid resistance protein inner membrane
6,65
adiC, arginine:agmatine antiporter
5,06
hypA, protein involved in nickel insertion into hydrogenases 3
4,92
dctR, Putative LuxR family repressor for dicarboxylate transport
4,82
gadA, glutamate decarboxylase A PLP-dependent
4,75
hycE, hydrogenase 3 large subunit
4,24
adiA, arginine decarboxylase
4,11
slp, outer membrane lipoprotein
3,88
fdhF, formate dehydrogenase-H selenopolypeptide subunit
3,80
hypB, GTP hydrolase involved in nickel liganding into hydrogenases
3,69
hyaC, hydrogenase 1 b-type cytochrome subunit
3,68
ybaE, putative ABC transporter periplasmic binding protein
3,67
hycG, hydrogenase 3 and formate hydrogenase complex HycG subunit
3,28
mglA, methyl-galactoside ABC transporter ATPase
3,17
hypD, hydrogenase maturation protein
2,96
hycH, hydrogenase 3 maturation protein
2,84
zntA, zinc cobalt and lead efflux system
0,39
yebE, DUF533 family inner membrane protein
0,39
wcaE, putative glycosyl transferase
0,32
ssuD, alkanesulfonate monooxygenase FMNH(2)-dependent
0,30
tauC, taurine ABC transporter permease
0,30
ssuE, NAD(P)H-dependent FMN reductase
0,21
https://doi.org/10.1371/journal.pone.0175197.t001 https://doi.org/10.1371/journal.pone.0175197.t001 low-oxygen stress experienced by the biofilm grown under these conditions (Fig 8B). O2 thus
appears as a potentially limited resource under confined flow conditions. low-oxygen stress experienced by the biofilm grown under these conditions (Fig 8B). O2 thus
appears as a potentially limited resource under confined flow conditions. Increasing the flow rate by a factor of 4 in the 250 μm-height channel induced an increase
of the channel fluid oxygen content (Fig 8C). The non-monotonical shape of the curve may
result from a reduction of the net balance of O2 under conditions where the influx of advected
O2 does not compensate the removal by the flow of the O2 contributed to the fluid by diffusion
from the PDMS. The results displayed in Fig 8C indicates that advection rate contributes to O2
equilibrium in such millifluidic channels. However, it’s worth noting that we measured oxygen
content in the channel fluid flow, which is not necessarily unequivocally related to the O2 level
sensed by the cells in the biofilm. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Biofilms under flow in a millifluidic channel grow under a low partial
pressure of oxygen As the transcriptomic analysis pointed to distinct levels of micro-aerobiosis under the two
characteristic hydrodynamic conditions, we wanted to evaluate the direct impact of hydrody-
namics on O2 supply in our setup. To assess oxygen supply in our specific configuration, we
carried out an experimental determination of the partial pressure of O2 in the two channels,
using Ruthenium micelle fluorescence. We first measured O2 content in the 1 mm- and 250 μm- height channels supplied with
growth medium at 1 mL/h in the absence of biofilm to evaluate the possible effect of channel
geometry on oxygen availability. We found no significant difference between the two channels—
the partial pressures were found equal to 5.0±0.1% and 5.3±0.2% for the 1 mm and 250 μm-
height channels, respectively. Increasing the flow rate up to 2 mL/h did not modify the O2 levels
(Fig 8A). These values, which were also found in the M63B1-glucose stock solution, are typical
of resting aqueous solutions in contact with atmospheric air. Besides, when flow was stopped, we
measured slightly higher levels of O2, suggesting that the PDMS walls, which are intrinsically
permeable to O2, released their O2 content in the channel lumen in the absence of flow—an O2
content higher in PDMS than in the surrounding air has already been shown elsewhere[50]. Next, we monitored oxygen level in the 250 μm-height channel in the presence of a biofilm
after 12 hours of growth. Only the advancing-front growth mode, which preserved a central
region devoid of biofilm in the channel, allowed probe fluorescence intensity interpretation in
terms of O2 concentration in the flow. Thereby, we found a stationary O2 level significantly
reduced in comparison with the empty channels: the pO2 value was 1.2±0.1%, vs. 5% in the
empty channels. This drop accounted for O2 consumption by the biofilm and confirmed the PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 13 / 24 Bacterial biofilm response to hydrodynamics Table 1. Genes most affected in expression in biofilms under flow: low fluid dynamical regime (L) ver-
sus high fluid dynamical regime (H). Second column is the ratio between mean normalized transcriptional
expressions. Anaerobic metabolism genes (Bold), acid resistance genes (Italic), Sulfate metabolism genes
(Underlined). Table 1. Genes most affected in expression in biofilms under flow: low fluid dynamical regime (L) ver-
sus high fluid dynamical regime (H). Second column is the ratio between mean normalized transcriptional
expressions. Biofilms under flow in a millifluidic channel grow under a low partial
pressure of oxygen (B) pO2 in
250 μm- height channel at 1 ml/h, in the presence (dark red) or absence (light red) of a growing biofilm 12
hours after initiation. (C) pO2 vs. flow rate in a 250 μm—height channel in the presence of the growing biofilm. Error bars (smaller than dots in C) represent standard deviation over two measurements. https://doi.org/10.1371/journal.pone.0175197.g008 Biofilms under flow in a millifluidic channel grow under a low partial
pressure of oxygen Besides, while the different growth rates measured in the bio-
films growing in our 250 μm- and 1 mm-height channels might arise from different oxygen
levels, the distinct development patterns exhibited by these biofilms may also directly impact
the growth rate. The main result we obtained from this evaluation of environmental O2 concentration is
that biofilms under flow in millifluidic channels grow under low oxygen level. This is consis-
tent with the modulation of the micro-aerobiosis functions revealed by the transcriptomics
data. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 14 / 24 Bacterial biofilm response to hydrodynamics Discussion
We have disentangled the features that impact bacterial biofilm formation under hydrody-
b
(
l d
l
h
)
d
d
l d
Fig 8. Biofilm grows at low O2 level in a millifluidic channel. Oxygen partial pressure (pO2) is measured in
the channel fluid using Ruthenium micelles fluorescence (see Materials and Methods). (A) pO2 in empty
channels at different flow rates (0; 1 and 2 ml/h), in 250 μm- (red) and 1 mm- (blue) height channels. (B) pO2 in
250 μm- height channel at 1 ml/h, in the presence (dark red) or absence (light red) of a growing biofilm 12
hours after initiation. (C) pO2 vs. flow rate in a 250 μm—height channel in the presence of the growing biofilm. Error bars (smaller than dots in C) represent standard deviation over two measurements. https://doi.org/10.1371/journal.pone.0175197.g008 Fig 8. Biofilm grows at low O2 level in a millifluidic channel. Oxygen partial pressure (pO2) is measured in
the channel fluid using Ruthenium micelles fluorescence (see Materials and Methods). (A) pO2 in empty
channels at different flow rates (0; 1 and 2 ml/h), in 250 μm- (red) and 1 mm- (blue) height channels. (B) pO2 in
250 μm- height channel at 1 ml/h, in the presence (dark red) or absence (light red) of a growing biofilm 12
hours after initiation. (C) pO2 vs. flow rate in a 250 μm—height channel in the presence of the growing biofilm. Error bars (smaller than dots in C) represent standard deviation over two measurements. Fig 8. Biofilm grows at low O2 level in a millifluidic channel. Oxygen partial pressure (pO2) is measured in
the channel fluid using Ruthenium micelles fluorescence (see Materials and Methods). (A) pO2 in empty
channels at different flow rates (0; 1 and 2 ml/h), in 250 μm- (red) and 1 mm- (blue) height channels. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Bacterial biofilm response to hydrodynamics Here, we tackled this problem by using millifluidic channels of variable height to apply a
range of shear stresses under the same flow rate and a limited variation of the advection rate. Based on this setup, we first recognized, using the theoretical velocity expressions of
O’Brien[40], that millifluidic geometries provided shear stress values already broadly distrib-
uted within a unique channel. While a growing number of investigations of biofilms under
flow are using flow cell channels with similar dimensions[5, 21, 51, 52], this property has
essentially been overlooked so far. Our strategy consisted in achieving real-time monitoring of the biofilm growth to quantita-
tively assess its spatiotemporal development under controlled shear stress conditions. This
approach enabled to disentangle the settling initiation events and the subsequent growth of the
material under flow. Looking into the details of the initial biofilm development patterns and kinetics within the
five channels of our setup, we found a mechanical control of biofilm settlement. Above a
threshold shear stress value of 10 mPa, no direct initiation of the biofilm on the surface could
occur. Interestingly, if we evaluate the tangential force, F = σ. A, applied by such a shear stress
on a surface A of 1 μm2 (approx. the average projected surface of an E. coli), we obtain a value
of 10−2 pN. Using a more sophisticated evaluation of the drag force, as in De La Fuente et al. [53], also yields a value below 0.1 pN. Such forces acting over 1 μm will barely engage a few
kBT, which is lower than the energy required to break molecular bonds attaching a bacterium
to a surface. Forces needed to break even a single bond would be of the order of a few to a few
tens of piconewtons[54, 55]. Our finding thus suggests that only weak interaction forces such
as hydration, van der Waals or electrostatic forces compatible with an amplitude of some hun-
dredths of piconewtons[56, 57] retain bacteria on the surface during the initiation phase. This
soft adhesion is sufficient to enable cells to resist shear stress up to a 10 mPa threshold and to
start building a biofilm. Such weak forces have rarely been reported to interfere with biofilm
formation, very likely due to the authors’ usual focus on forces required to remove mature bio-
film, which appear to be different from forces hindering initial adhesion[57]. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Discussion We have disentangled the features that impact bacterial biofilm formation under hydrody-
namic stress, a ubiquitous process in nature (including living hosts) and in industrial devices. To date, the question of flow effects on biofilm development has remained confused, very
likely because fluid flow simultaneously determines the amplitude of several driving forces
very distinct by nature but technically difficult to separate, such as mechanical stress and solute
transport. 15 / 24 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Bacterial biofilm response to hydrodynamics coding for membrane stress-sensing ionic channels[35], or even csg, cpx or rpoS genes involved
in more generic surface-sensing systems[60]. The absence of significant mechano-specific biological signaling in the biofilm, in response
to the environmental mechanical stress increase, is consistent with the fact that no fluid flow
penetrated into the biofilm. Indeed, the latter observation implies that most of the biofilm-
dwelling cells live protected from mechanical stress, which is thus expected to only affect the
interface layer. At this point, it is important to discuss the limitations of biofilm transcriptional
profiling. In particular, the whole transcriptome captures a gene expression pattern averaged
over the whole cell population, regardless of the strong spatial heterogeneity of the biofilm and
of the conditions[61]. Thus, a small sub-population with specific expression levels would be
missed by this analysis, and we cannot exclude overlooking the response of a minority popula-
tion such as an interface layer, for instance. Besides, the differential transcriptomic analysis
principally pointed to a set of genes involved in cell micro-aerobiosis, indicating that the bio-
film grown under lower fluid dynamics exhibited enhanced low-O2 stress than its higher fluid
dynamics counterpart. In addition, four genes involved in cell resistance to acidic conditions
are more strongly expressed at lower fluid dynamics—possibly regarding metabolite removal
by the flow—and 3 genes related to sulfate metabolism, were less expressed. The micro-aerobi-
osis genes also appeared to be more strongly expressed in cells from both channels than in
planktonic agitated log-phase cells, as expected. The micro-aerobiosis genes have only been
previously mentioned in transcriptomic characterization of biofilm traits by Schembri et al. [48, 62], very likely due to the extreme sensitivity of transcriptomes to experimental condi-
tions. As pointed out by Beloin and Ghigo[62], transcriptomes obtained on E. coli biofilm-
dwelling cells are difficult to compare across laboratories. In addition, very few transcriptomic
analyses have been performed on biofilms under flow. Yet, looking at the top 20 genes sorted
in our analysis when comparing the gene expression in the biofilm under low fluid dynamics
with the one in an exponentially growing cell culture, we found that in our analysis, 15 genes
are in common with the list published by Schembri and collaborators[48, 63] (S3 Table) whose
conditions are close to ours. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Worthy of men-
tion is the fact that the exact amount of energy engaged in this surface initial dwelling of
bacteria will undoubtedly depend on the precise physicochemical properties of the cell and of
the substrate surfaces but it is important to notice that even weak cell/surface interactions may
eventually lead to a mature robust biofilm. Given the increase of the apparent lag time of bio-
film growth with shear stress, we also suggest that flow might delay the formation of this con-
ditioning layer, simply by partially washing out the molecules secreted by the cells. This
hypothesis, which has not received much attention so far, would deserve further investigation
to decide whether a hydrodynamic, mechanical forces-independent mechanism simply driven
by diffusion and advection, participates in the control of biofilm initiation. hypothesis, which has not received much attention so far, would deserve further investigation
to decide whether a hydrodynamic, mechanical forces-independent mechanism simply driven
by diffusion and advection, participates in the control of biofilm initiation. Next, we addressed the question of the biological response of biofilms to shear stress as a
mechanical force, focusing on biofilm growth. Through initiation control, hydrodynamics ori-
ented biofilm growth towards two different modes: one under low shear stress, in which bio-
film grows from uniform surface attachment—that we called uniform growth mode—and one
under higher shear stress in which biofilm grows from the channel side walls after a delay—the
advancing-front growth mode. We demonstrated that the biofilms growing in the uniform mode at bottom shear stress val-
ues ranging from 0.42 to 10 mPa (32 growth curves) all displayed the same growth rate, indi-
cating that the intensity of mechanical stress did not impact biofilm growth rate per se. In good
agreement with this finding, the global transcriptome analysis that we performed on biofilms
grown at low and high shear stress exhibited no significant differential expression of mechano-
sensing-related genes, such as flh or fli genes related to flagellar function[58, 59], msc genes PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 16 / 24 By contrast, only one gene was found in common with the list of
Beloin and collaborators[63] whose setup consisted in a slide immersed in a quasi-static che-
mostat for 8 days. Nevertheless, despite the low level of citations of the low O2- stress genes in
the whole transcriptome studies dedicated to biofilms, more and more studies demonstrate
the role of O2 availability as a pivotal driving force underlying bacterial community behavior
[64–66]. Our results indicated that biofilms under flow in milllifluidic channels experience low-O2
medium conditions consistent with the micro-aerobiosis detected by the transcriptomic analy-
sis. The reduced low-O2 stress observed under the higher fluid dynamics conditions indicates
that in the advancing-front mode, the biofilm had a better access to O2. This may be due to its
distinct pattern, advantageous to benefit from the different sources of O2 in the millifluidic
channel, such as the environmental air transported through the PDMS walls. However, it may
also be due to the slightly higher advection rate. Further elucidation of the causal relationships
linking hydrodynamics, oxygen level and biofilm growth would require additional experi-
ments enabling in situ determination of O2 distribution within the biofilm under flow. Our findings also highlight a stress-escaping strategy developed by this E. coli strain to
finally settle biofilm in areas initially precluded due to too high shear stress, such as the center
of the strongly confined channels. This strategy consists in settling in flow-protected borders
before quickly expanding—albeit after a delay—towards the previously forbidden zones, in a
more mature and topologically favorable form. This is a crucial result to have in mind to con-
ceive fluidic circuits where bacteria will pass and try to dwell. Should you aim at fighting PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 17 / 24 Bacterial biofilm response to hydrodynamics against or at domesticating the biofilm, the flow properties at the device boundaries should be
carefully examined. against or at domesticating the biofilm, the flow properties at the device boundaries should be
carefully examined. Conclusions Hydrodynamics has an exquisite influence on the development of 3D biofilm. Under laminar
flow and mild shear stress, mechanical forces have a veto power on initial surface colonization. It induces a spatial patterning of the biofilm that reflects settlement in zones of permissive
shear stress. However, no mechanotransduction process has been found here to significantly
contribute to biofilm physiological properties. Biofilm appears as a bacterial strategic bypass of
the hydrodynamic barrier opposed to their surface invasion: settling in shear stress protected
areas, they dwell there long enough to mature into a material able to expand in the previously
forbidden areas, although with a delay and a modified pattern. Hydrodynamic molecular
transport essentially impacts the subsequent growth phase of the biofilm. The control of oxy-
gen distribution—a key factor of the biofilm lifestyle—appears as an essential regulation ele-
ment carried by the fluid flow. These features are of utmost importance to understand and anticipate biofilm development
as well as to achieve informed design of fluidic setups either to investigate biofilm fundamental
properties or to engineer and control these adherent bacterial communities. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 other details as in Fig 2A.
(AVI) S1 Fig. Signal calibration. (A) Microphotometry measurements. The natural logarithm of the
light attenuation factor—ln(I0/I), so-called microscopic absorbance Aμ—was derived from
microscope image intensities obtained on methylene blue and biofilm samples of different
concentrations in the millifluidic channel series. Then Aμ was plotted against sample concen-
trations determined independently. For methylen blue (MBlue) (blue triangles), we used solutions of known concentrations and
considered the quantity [MBlue].h, i.e. the mass concentration multiplied by the height of the
measured channel, to take into account the path of the light in the solution (top x-axis). For biofilms (open circles) we extracted the material from the channels using repeated air jet
pulses and thoroughly dispersed it in 300 μl of minimum medium to measure optical density
at 600 nm (macroscopic OD). Considering an OD-specific concentration of E. coli cells in a
suspension, i.e. the number of cells per milliliter at an OD of 1 measured at 600 nm, equal to
5.108 cells/mL, we deduced the number of cells per channel (bottom x-axis). The analogue absorbance, ln(I0/I), derived from microscope images, increased mostly linearly
with sample mass concentration up to approx. 60% attenuation (ln(I0/I) = 0.35). Interestingly,
the same behavior regarding linearity deviation was observed for MBlue solutions and bio-
films, indicating that light attenuation measured in microscopy on biofilms approx. 100 μm in
height was not significantly impaired by scattering. Therefore, the analogue absorbance could
be taken as an accurate mass concentration proxy, provided that the proportionality factor and
the limit of the linear regime can be determined. (B) Incident light (I0) effect on analogue absorbance-mass concentration relationship. A ten-
channel series was prepared with increasing concentrations of methylene blue and the ana-
logue absorbance was measured for two different intensities of incident light; (black circles)
I0 = 2140 ±110 a.u. and (gray triangles) I0 = 526±20 a.u. Increasing incident light intensity
increases the range of quasi-linearity of the analogue absorbance-concentration relation. Quantitative analyses of biofilm growth experiments were performed using I0 = 2000±100 a.u. ensuring a quasi-linear detection of the biomass in the channel up to an absorbance value of
0.7; i.e. an attenuation of 50%. g
q
y
g
Quantitative analyses of biofilm growth experiments were performed using I0 = 2000±100 a.u. ensuring a quasi-linear detection of the biomass in the channel up to an absorbance value of
0.7; i.e. an attenuation of 50%. Bacterial biofilm response to hydrodynamics S1 File. Estimation of glucose concentration.
(PDF) S1 Video. Biofilm growth imaging over 20 hours in 1 mm-height channel. Biofilm initiated
as in Material and Methods section. Movie starts at the same time as image acquisition. Bright-
field using a 20X objective. Acquisition time is 20msec, one frame every 5 mins. All other
details as in Fig 2A. (AVI) S2 Video. Biofilm growth imaging over 20 hours in 750 μm-height channel. Biofilm initi-
ated as in Material and Methods section. Movie starts at the same time as image acquisition. Brightfield using a 20X objective. Acquisition time is 20msec, one frame every 5 mins. All
other details as in Fig 2A. (AVI) S3 Video. Biofilm growth imaging over 20 hours in 500 μm-height channel. Biofilm initi-
ated as in Material and Methods section. Movie starts at the same time as image acquisition. Brightfield using a 20X objective. Acquisition time is 20msec, one frame every 5 mins. All
other details as in Fig 2A. (AVI) S4 Video. Biofilm growth imaging over 20 hours in 350 μm-height channel. Biofilm initi-
ated as in Material and Methods section. Movie starts at the same time as image acquisition. Brightfield using a 20X objective. Acquisition time is 20msec, one frame every 5 mins. All
other details as in Fig 2A. (AVI) S5 Video. Biofilm growth imaging over 20 hours in 250 μm-height channel. Biofilm initi-
ated as in Material and Methods section. Movie starts at the same time as image acquisition. Brightfield using a 20X objective. Acquisition time is 20msec, one frame every 5 mins. All PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 18 / 24 other details as in Fig 2A.
(AVI) In that case, since the flow rate is kept constant during the experiment,
we adjusted the velocity field separately at each time point (with h as the only adjustable
parameter) at given imposed values of Q, and we then chose the one that minimized the total
sum of the squared residues over all times, yielding Q = 0.85 mL/h, consistent with the
adjusted value Q = 0.83 mL/h obtained here. Black lines: distance between the experimentally-measured velocities and the adjusted values
at the same location. Both the height h and the volumetric flow rate Q (through—η dp/dx)
were adjusted, as in the presence of the biofilm (Fig 6), yielding h = 1.00 mm as expected, and
Q = 0.83 mL/h (nominal value 1 mL/h). The coefficient of determination of the fit is R2 = 0.92. Since the velocity flow in this biofilm-free channel was consistent with a flow rate slightly
lower than the nominal value, the flow rate Q was also adjusted in the same channel with grow-
ing biofilm (Fig 6A). In that case, since the flow rate is kept constant during the experiment,
we adjusted the velocity field separately at each time point (with h as the only adjustable
parameter) at given imposed values of Q, and we then chose the one that minimized the total
sum of the squared residues over all times, yielding Q = 0.85 mL/h, consistent with the
adjusted value Q = 0.83 mL/h obtained here. B: Velocity field in a channel of height h = 250 μm without biofilm. Dots: experimentally-mea-
sured velocities v at various positions (y, z) across the channel. Surface: adjustment to the theo-
retical expression of the velocity field of a viscous fluid in a rectangular channel (Eq 2) The
color scale denotes velocities (see v axis) and is the same as in Fig S2A for the sake of compari-
son. Black lines: distance between the experimentally-measured velocities and the adjusted val-
ues at the same location. Both the width w and the effective position y0 of the no-slip boundary
condition in the y direction were adjusted, as in the presence of the biofilm (Fig 1), yielding
w = 1.08 mm and y0 = 6.5 μm, consistent with the expectations (w = 1.0 mm and y0 = 0). The
volumetric flow rate Q was set to its experimentally-imposed nominal value 1 mL/h. other details as in Fig 2A.
(AVI) From these data, we obtained the relationship linking the absorbance Aμ and the number Nch
of cells per channel: Aμ = (1.1±0.2)x10-9 Nch. Then, assuming uniform colonization of the
channel, we deduced the relationship linking Aμ and the surfacic concentration Cs, defined as
the number of cells dwelling over 1 mm2 channel surface, i.e. Cs = (3.0±0.2).x107 Aμ, by divid-
ing Nch by the channel surface 30 mm2. In our quantitative analysis of biofilm growth curves (see main text and Figs 3–5), we took
into account only data with measured absorbance values <0.74, in order to remain in the
quasi-linear region of the absorbance-concentration (or absorbance-biomass) relation. To fur-
ther correct for the slight nonlinearities present even at low absorbance values in this relation,
we used the experimentally-measured relation in panel (B), yielding the equivalent [Mblue].h
corresponding to each measured absorbance. This equivalent [Mblue].h is termed “corrected
absorbance” in the main text. This correction, which can be visualized on Fig 3, yields better
exponential adjustments. S2 Fig. Velocity field in channels without biofilm. A: Velocity field in a channel of height
h = 1 mm without biofilm. Dots: experimentally-measured velocities v at various positions (y,
z) across the channel. Surface: adjustment to the theoretical expression of the velocity field of a
viscous fluid in a rectangular channel (Eq 2). The color scale denotes velocities (see v axis). 19 / 24 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Bacterial biofilm response to hydrodynamics Black lines: distance between the experimentally-measured velocities and the adjusted values
at the same location. Both the height h and the volumetric flow rate Q (through—η dp/dx)
were adjusted, as in the presence of the biofilm (Fig 6), yielding h = 1.00 mm as expected, and
Q = 0.83 mL/h (nominal value 1 mL/h). The coefficient of determination of the fit is R2 = 0.92. Since the velocity flow in this biofilm-free channel was consistent with a flow rate slightly
lower than the nominal value, the flow rate Q was also adjusted in the same channel with grow-
ing biofilm (Fig 6A). other details as in Fig 2A.
(AVI) (Note
that choosing instead to adjust Q gives consistent results, e.g. Q = 0.97 mL/h in the presence of
the biofilm.) The coefficient of determination of the fit is R2 = 0.97. (TIF) S3 Fig. Experimental velocity measurement. Picture of red fluorescent particles (exc 580 nm/
em 605 nm) 1 μm in diameter flowing in a 1 mm-height channel under continuous medium
supply at a nominal flow rate of 1 ml/h. Image recorded with a 40 msec acquisition time. z-
stack images are collected using a z spacing of 5 μm. The displayed image has been recorded at
z = 900 μm. Only on-focus trails, as shown in the insert, are taken into account for the velocity
field determination. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 S4 Fig. Differential expression of the genes coding for cytochrome bd and bo oxidases. g
p
g
g
y
Consistently with the hypothesis that bacteria in L samples experienced lower level of O2 than
in H samples, we found that the genes coding for cytochrome bd and bo oxidases, the activity
of which is known to be related to the fraction of aerobiosis (Alexeeva, S., Hellingwerf, K. J. &
Teixeira de Mattos, M. J. Quantitative assessment of oxygen availability: perceived aerobiosis
and its effect on flux distribution in the respiratory chain of Escherichia coli. J Bacteriol 184,
1402–1406 (2002)), were differently expressed in H and L (although with an FDR>0.01); the
levels of expression in samples E are also consistent with a better level of oxygenation in sam-
ples E, as expected. Left panel: expression of cbdAB coding for cytochrome bd oxidase, which
contributes to respiratory activity below 50% aerobiosis; expression is higher in samples L
compared to samples H, and genes are repressed in samples E. Right panel: expression of
cyoABCDE coding for cytochrome bo oxidase, which contributes significantly to respiratory
activity above 55% aerobiosis; expression is higher in samples E and lower in samples L, con-
sistent with a better oxygenation in samples E and a lower oxygenation in samples L. Bars:
SDs 20 / 24 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Bacterial biofilm response to hydrodynamics S5 Fig. Kymographs of biofilm development under different hydrodynamical conditions. On each kymograph, the length scales on the top axis stand for the distance from the edge of
the channel while the time scale on the right reports time elapsed from the start of the flow. (a)
0.5 mm-height channel under 1 mL/h flow rate, i.e. shear stress up to 9 mPa; the uniform
growth mode is observed, indicating that the colonization shear stress threshold is above 9
mPa. (b) 0.35 and (c) 0.25 mm height channels under 1 mL/h flow rate; the limit for the initial
colonization corresponds in these channels to shear stress values of 10 mPa and 13mPa, S5 Fig. Kymographs of biofilm development under different hydrodynamical conditions. On each kymograph, the length scales on the top axis stand for the distance from the edge of
the channel while the time scale on the right reports time elapsed from the start of the flow. (a)
0.5 mm-height channel under 1 mL/h flow rate, i.e. S1 Table. Data statistical dispersion. Means and standard deviations over at least three dis-
tinct channels.
(PDF) S1 Table. Data statistical dispersion. Means and standard deviations over at least three dis-
tinct channels. (PDF) S2 Table. Growth rates are higher in the higher fluid dynamical regime. Growth rate values
derived from the exponential fit of the biomass growth kinetics in the different channels (μ). (PDF) S2 Table. Growth rates are higher in the higher fluid dynamical regime. Growth rate values
derived from the exponential fit of the biomass growth kinetics in the different channels (μ). (PDF) S3 Table. The 20 genes most affected in expression: biofilm versus exponential growth
phase; comparison with two other experiments. (PDF) Acknowledgments We thank Carounagarane Dore for technical assistance and Claude Loverdo and Georges Deb-
regeas for fruitful discussions. We thank Carounagarane Dore for technical assistance and Claude Loverdo and Georges Deb-
regeas for fruitful discussions. The work was supported in part by a grant from the French Agence Nationale pour la
Recherche (ANR-15-CE02-0001-01 ACToP). The work was supported in part by a grant from the French Agence Nationale pour la
Recherche (ANR-15-CE02-0001-01 ACToP). S4 Fig. Differential expression of the genes coding for cytochrome bd and bo oxidases. shear stress up to 9 mPa; the uniform
growth mode is observed, indicating that the colonization shear stress threshold is above 9
mPa. (b) 0.35 and (c) 0.25 mm height channels under 1 mL/h flow rate; the limit for the initial
colonization corresponds in these channels to shear stress values of 10 mPa and 13mPa,
respectively. (d) A 0.5 mm-height channel was run at a different flow rate of 2mL/h; the limit
of initial colonization consistent with a shear stress colonization threshold of 11 mPa. Dashed
lines indicate initial shear stress whitin the fcolonization. (TIF) respectively. (d) A 0.5 mm-height channel was run at a different flow rate of 2mL/h; the limit
of initial colonization consistent with a shear stress colonization threshold of 11 mPa. Dashed
lines indicate initial shear stress whitin the fcolonization. (
) PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 References 1. Stoodley P, Sauer K, Davies DG, Costerton JW. Biofilms as complex differentiated communities. Annu
Rev Microbiol. 2002; 56:187–209. https://doi.org/10.1146/annurev.micro.56.012302.160705 PMID:
12142477 2. Hall-Stoodley L, Costerton JW, Stoodley P. Bacterial biofilms: from the natural environment to infectious
diseases. Nat Rev Microbiol. 2004; 2(2):95–108. Epub 2004/03/26. https://doi.org/10.1038/nrmicro821
PMID: 15040259 3. Kolter R, Greenberg EP. Microbial sciences: the superficial life of microbes. Nature. 2006; 441
(7091):300–2. https://doi.org/10.1038/441300a PMID: 16710410 4. Cunliffe M, Murrell JC. The sea-surface microlayer is a gelatinous biofilm. Isme Journal. 2009; 3
(9):1001–3. https://doi.org/10.1038/ismej.2009.69 PMID: 19554040 5. Rusconi R, Garren M, Stocker R. Microfluidics expanding the frontiers of microbial ecology. Annu Rev
Biophys. 2014; 43:65–91.022916. https://doi.org/10.1146/annurev-biophys-051013-022916 PMID:
24773019 6. Kim J, Park HD, Chung S. Microfluidic approaches to bacterial biofilm formation. Molecules. 2012; 17
(8):9818–34. https://doi.org/10.3390/molecules17089818 PMID: 22895027 7. Pamp SJ, Sternberg C, Tolker-Nielsen T. Insight into the microbial multicellular lifestyle via flow-cell
technology and confocal microscopy. Cytometry A. 2009; 75(2):90–103. https://doi.org/10.1002/cyto.a. 20685 PMID: 19051241 8. Vo GD, Heys J. Biofilm deformation in response to fluid flow in capillaries. Biotechnol Bioeng. 2011; 108
(8):1893–9. https://doi.org/10.1002/bit.23139 PMID: 21437881 9. Coetser SE, Cloete TE. Biofouling and biocorrosion in industrial water systems. Crit Rev Microbiol. 2005; 31(4):213–32. https://doi.org/10.1080/10408410500304074 PMID: 16417202 10. Aggarwal S, Hozalski RM. Effect of Strain Rate on the Mechanical Properties of Staphylococcus epider-
midis Biofilms. Langmuir. 2012; 28(5):2812–6. https://doi.org/10.1021/la204342q PMID: 22217007 11. Castro SL, Nelman-Gonzalez M, Nickerson CA, Ott CM. Induction of Attachment-Independent Biofilm
Formation and Repression of hfq Expression by Low-Fluid-Shear Culture of Staphylococcus aureus. Appl Environ Microbiol. 2011; 77(18):6368–78. https://doi.org/10.1128/AEM.00175-11 PMID:
21803898 12. Alpkvist E, Klapper I. Description of mechanical response including detachment using a novel particle
model of biofilm/flow interaction. Water Sci Technol. 2007; 55(8–9):265–73. PMID: 17546995 13. Cense AW, Peeters EA, Gottenbos B, Baaijens FP, Nuijs AM, van Dongen ME. Mechanical properties
and failure of Streptococcus mutans biofilms, studied using a microindentation device. J Microbiol Meth-
ods. 2006; 67(3):463–72. https://doi.org/10.1016/j.mimet.2006.04.023 PMID: 16820233 14. Stoodley P, Cargo R, Rupp CJ, Wilson S, Klapper I. Biofilm material properties as related to shear-
induced deformation and detachment phenomena. J Ind Microbiol Biotechnol. 2002; 29(6):361–7. https://doi.org/10.1038/sj.jim.7000282 PMID: 12483479 15. Stoodley P, Lewandowski Z, Boyle JD, Lappin-Scott HM. Structural deformation of bacterial biofilms
caused by short-term fluctuations in fluid shear: an in situ investigation of biofilm rheology. Biotechnol
Bioeng. 1999; 65(1):83–92. PMID: 10440674 16. Wang IW, Anderson JM, Jacobs MR, Marchant RE. Conceptualization: PT NH. Formal analysis: PT AFB NH. Funding acquisition: NH. Investigation: PT JR AM AFB CD NH. Methodology: PT AFB NH. Methodology: PT AFB NH. Project administration: NH. Resources: CD. Resources: CD. Software: PT AFB NH. Software: PT AFB NH. Supervision: NH. Visualization: PT AFB NH. Writing – original draft: PT NH. Writing – review & editing: PT AFB NH. 21 / 24 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Bacterial biofilm response to hydrodynamics PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 References Adhesion of Staphylococcus epidermidis to bio-
medical polymers: contributions of surface thermodynamics and hemodynamic shear conditions. Jour-
nal of biomedical materials research. 1995; 29(4):485–93. https://doi.org/10.1002/jbm.820290408
PMID: 7622533 17. Franke RP, Grafe M, Schnittler H, Seiffge D, Mittermayer C, Drenckhahn D. Induction of human vascu-
lar endothelial stress fibres by fluid shear stress. Nature. 1984; 307(5952):648–9. PMID: 6537993 18. Marquezin CA, Ceffa NG, Cotelli F, Collini M, Sironi L, Chirico G. Image Cross-Correlation Analysis of
time varying flows. Anal Chem. 2016. Epub 2016/06/28. 19. Droppo IG, Krishnappan BG, Liss SN, Marvin C, Biberhofer J. Modelling sediment-microbial dynamics
in the South Nation River, Ontario, Canada: Towards the prediction of aquatic and human health risk. Water Res. 2011; 45(12):3797–809. https://doi.org/10.1016/j.watres.2011.04.032 PMID: 21558043 20. Grant MA, Waclaw B, Allen RJ, Cicuta P. The role of mechanical forces in the planar-to-bulk transition
in growing Escherichia coli microcolonies. J R Soc Interface. 2014; 11(97):20140400. https://doi.org/10. 1098/rsif.2014.0400 PMID: 24920113 21. Shen Y, Siryaporn A, Lecuyer S, Gitai Z, Stone HA. Flow directs surface-attached bacteria to twitch
upstream. Biophys J. 2012; 103(1):146–51. https://doi.org/10.1016/j.bpj.2012.05.045 PMID: 22828341 22. Thomas WE, Trintchina E, Forero M, Vogel V, Sokurenko EV. Bacterial adhesion to target cells
enhanced by shear force. Cell. 2002; 109(7):913–23. PMID: 12110187 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 22 / 24 Bacterial biofilm response to hydrodynamics 23. Lecuyer S, Rusconi R, Shen Y, Forsyth A, Vlamakis H, Kolter R, et al. Shear stress increases the resi-
dence time of adhesion of Pseudomonas aeruginosa. Biophysical journal. 2011; 100(2):341–50. https://
doi.org/10.1016/j.bpj.2010.11.078 PMID: 21244830 24. Kim MK, Ingremeau Fß, Zhao A, Bassler BL, Stone HA. Local and global consequences of flow on bac-
terial quorum sensing. Nature Microbiology. 2016; 1:15005. https://doi.org/10.1038/nmicrobiol.2015.5
PMID: 27571752 25. Kirisits MJ, Margolis JJ, Purevdorj-Gage BL, Vaughan B, Chopp DL, Stoodley P, et al. Influence of the
hydrodynamic environment on quorum sensing in Pseudomonas aeruginosa biofilms. J Bacteriol. 2007;
189(22):8357–60. https://doi.org/10.1128/JB.01040-07 PMID: 17704224 26. Otto M. Physical stress and bacterial colonization. FEMS Microbiol Rev. 2014; 38(6):1250–70. https://
doi.org/10.1111/1574-6976.12088 PMID: 25212723 27. Kim J, Kim HS, Han S, Lee JY, Oh JE, Chung S, et al. Hydrodynamic effects on bacterial biofilm devel-
opment in a microfluidic environment. Lab Chip. 2013; 13(10):1846–9. https://doi.org/10.1039/
c3lc40802g PMID: 23576069 28. Liu Y, Tay JH. Metabolic response of biofilm to shear stress in fixed-film culture. J Appl Microbiol. 2001;
90(3):337–42. PMID: 11298227 29. Mbaye S, Sechet P, Pignon F, Martins JM. References Influence of hydrodynamics on the growth kinetics of glass-
adhering Pseudomonas putida cells through a parallel plate flow chamber. Biomicrofluidics. 2013; 7
(5):54105. https://doi.org/10.1063/1.4821244 PMID: 24404068 30. Galy O, Latour-Lambert P, Zrelli K, Beloin C, Ghigo JM, Henry N. Mapping of bacterial biofilm local
mechanics by magnetic microparticle actuation. Biophysical journal. 2012; 5(6):1400–8. 31. Mathias JD, Stoodley P. Applying the digital image correlation method to estimate the mechanical prop-
erties of bacterial biofilms subjected to a wall shear stress. Biofouling. 2009; 25(8):695–703. https://doi. org/10.1080/08927010903104984 PMID: 20183128 32. Nickerson CA, Ott CM, Wilson JW, Ramamurthy R, LeBlanc CL, Honer zu Bentrup K, et al. Low-shear
modeled microgravity: a global environmental regulatory signal affecting bacterial gene expression,
physiology, and pathogenesis. J Microbiol Methods. 2003; 54(1):1–11. PMID: 12732416 33. Ingber DE. The mechanochemical basis of cell and tissue regulation. Mech Chem Biosyst. 2004; 1
(1):53–68. PMID: 16783946 34. Bershadsky AD, Balaban NQ, Geiger B. Adhesion-dependent cell mechanosensitivity. Annu Rev Cell
Dev Biol. 2003; 19:677–95. https://doi.org/10.1146/annurev.cellbio.19.111301.153011 PMID:
14570586 35. Kung C, Martinac B, Sukharev S. Mechanosensitive channels in microbes. Annu Rev Microbiol. 2010;
64:313–29. https://doi.org/10.1146/annurev.micro.112408.134106 PMID: 20825352 36. Siryaporn A, Kuchma SL, O’Toole GA, Gitai Z. Surface attachment induces Pseudomonas aeruginosa
virulence. Proc Natl Acad Sci U S A. 2014; 111(47):16860–5. https://doi.org/10.1073/pnas.1415712111
PMID: 25385640 37. Alsharif G, Ahmad S, Islam MS, Shah R, Busby SJ, Krachler AM. Host attachment and fluid shear are
integrated into a mechanical signal regulating virulence in Escherichia coli O157:H7. Proc Natl Acad Sci
U S A. 2015; 112(17):5503–8. https://doi.org/10.1073/pnas.1422986112 PMID: 25870295 38. Persat A, Inclan YF, Engel JN, Stone HA, Gitai Z. Type IV pili mechanochemically regulate virulence
factors in Pseudomonas aeruginosa. Proc Natl Acad Sci U S A. 2015; 112(24):7563–8. https://doi.org/
10.1073/pnas.1502025112 PMID: 26041805 39. Ghigo JM. Natural conjugative plasmids induce bacterial biofilm development. Nature. 2001; 412
(6845):442–5. https://doi.org/10.1038/35086581 PMID: 11473319 40. O’Brien V. Pulsatile fully developed flow in rectangular channels. Journal of The Franklin Institute. 1975;
300(3):225–30. 41. Figueroa-Morales N, Leonardo Mino G, Rivera A, Caballero R, Clement E, Altshuler E, et al. Living on
the edge: transfer and traffic of E. coli in a confined flow. Soft Matter. 2015; 11(31):6284–93. https://doi. org/10.1039/c5sm00939a PMID: 26161542 42. Liao Y, Smyth GK, Shi W. featureCounts: an efficient general purpose program for assigning sequence
reads to genomic features. Bioinformatics. 2014; 30(7):923–30. https://doi.org/10.1093/bioinformatics/
btt656 PMID: 24227677 43. Robinson MD, McCarthy DJ, Smyth GK. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 References edgeR: a Bioconductor package for differential expression
analysis of digital gene expression data. Bioinformatics. 2010; 26(1):139–40. https://doi.org/10.1093/
bioinformatics/btp616 PMID: 19910308 44. Robinson MD, Oshlack A. A scaling normalization method for differential expression analysis of RNA-
seq data. Genome Biol. 2010; 11(3):R25. https://doi.org/10.1186/gb-2010-11-3-r25 PMID: 20196867 23 / 24 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 Bacterial biofilm response to hydrodynamics 45. Douarche C, Buguin A, Salman H, Libchaber A. E. Coli and oxygen: a motility transition. Phys Rev Lett. 2009; 102(19):198101. https://doi.org/10.1103/PhysRevLett.102.198101 PMID: 19518998 46. Sud D, Zhong W, Beer DG, Mycek MA. Time-resolved optical imaging provides a molecular snapshot of
altered metabolic function in living human cancer cell models. Opt Express. 2006; 14(10):4412–26. PMID: 19516593 47. Trotter EW, Rolfe MD, Hounslow AM, Craven CJ, Williamson MP, Sanguinetti G, et al. Reprogramming
of Escherichia coli K-12 metabolism during the initial phase of transition from an anaerobic to a micro-
aerobic environment. PLoS One. 2011; 6(9):e25501. https://doi.org/10.1371/journal.pone.0025501
PMID: 21980479 48. Schembri MA, Kjaergaard K, Klemm P. Global gene expression in Escherichia coli biofilms. Mol Micro-
biol. 2003; 48(1):253–67. PMID: 12657059 49. Domka J, Lee J, Bansal T, Wood TK. Temporal gene-expression in Escherichia coli K-12 biofilms. Envi-
ron Microbiol. 2007; 9(2):332–46. https://doi.org/10.1111/j.1462-2920.2006.01143.x PMID: 17222132 50. Shiku H,., Saito T, Wu C, Yasukawa T, Yokoo M, Abe H, et al. Oxygen Permeability of Surface-modified
Poly(dimethylsiloxane) Characterized by Scanning Electrochemical Microscopy. Chemistry Letters. 2006; 35(2):234–5. 51. Song JL, Au KH, Huynh KT, Packman AI. Biofilm responses to smooth flow fields and chemical gradi-
ents in novel microfluidic flow cells. Biotechnol Bioeng. 2014; 111(3):597–607. https://doi.org/10.1002/
bit.25107 PMID: 24038055 52. Mosier AP, Kaloyeros AE, Cady NC. A novel microfluidic device for the in situ optical and mechanical
analysis of bacterial biofilms. J Microbiol Meth. 2012; 91(1):198–204. 53. De La Fuente L, Montanes E, Meng Y, Li Y, Burr TJ, Hoch HC, et al. Assessing adhesion forces of type
I and type IV pili of Xylella fastidiosa bacteria by use of a microfluidic flow chamber. Appl Environ Micro-
biol. 2007; 73(8):2690–6. https://doi.org/10.1128/AEM.02649-06 PMID: 17293518 54. Dufrene YF. Sticky microbes: forces in microbial cell adhesion. Trends Microbiol. 2015; 23(6):376–82. https://doi.org/10.1016/j.tim.2015.01.011 PMID: 25684261 55. Merkel R, Nassoy P, Leung A, Ritchie K, Evans E. Energy landscapes of receptor-ligand bonds
explored with dynamic force spectroscopy. Nature. 1999; 397(6714):50–3. https://doi.org/10.1038/
16219 PMID: 9892352 56. Israelachvili JN. Intermolecular and Surface Forces ( Third Edition). San Diego: Academic Press;
2011. p. 53–70. 57. PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017 References Boks NP, Norde W, van der Mei HC, Busscher HJ. Forces involved in bacterial adhesion to hydrophilic
and hydrophobic surfaces. Microbiol-Sgm. 2008; 154:3122–33. 58. Belas R. Biofilms, flagella, and mechanosensing of surfaces by bacteria. Trends Microbiol. 2014; 22
(9):517–27. https://doi.org/10.1016/j.tim.2014.05.002 PMID: 24894628 59. Persat A, Nadell CD, Kim MK, Ingremeau F, Siryaporn A, Drescher K, et al. The mechanical world of
bacteria. Cell. 2015; 161(5):988–97. https://doi.org/10.1016/j.cell.2015.05.005 PMID: 26000479 60. O’Toole GA, Wong GC. Sensational biofilms: surface sensing in bacteria. Curr Opin Microbiol. 2016;
30:139–46. https://doi.org/10.1016/j.mib.2016.02.004 PMID: 26968016 61. Stewart PS, Franklin MJ. Physiological heterogeneity in biofilms. Nat Rev Microbiol. 2008; 6(3):199–
210. https://doi.org/10.1038/nrmicro1838 PMID: 18264116 62. Beloin C, Ghigo JM. Finding gene-expression patterns in bacterial biofilms. Trends Microbiol. 2005; 13
(1):16–9. https://doi.org/10.1016/j.tim.2004.11.008 PMID: 15639627 63. Beloin C, Valle J, Latour-Lambert P, Faure P, Kzreminski M, Balestrino D, et al. Global impact of mature
biofilm lifestyle on Escherichia coli K-12 gene expression. Mol Microbiol. 2004; 51(3):659–74. PMID:
14731270 64. Geng J, Beloin C, Ghigo JM, Henry N. Bacteria Hold Their Breath upon Surface Contact as Shown in a
Strain of Escherichia coli, Using Dispersed Surfaces and Flow Cytometry Analysis. PLoS ONE. 2014; 9
(7):e102049. https://doi.org/10.1371/journal.pone.0102049 PMID: 25054429 65. Stewart PS, Zhang T, Xu R, Pitts B, Walters MC, Roe F, et al. Reaction-diffusion theory explains hyp-
oxia and heterogeneous growth within microbial biofilms associated with chronic infections. Npj Biofilms
And Microbiomes. 2016; 2:16012. 66. Okegbe C, Price-Whelan A, Dietrich LE. Redox-driven regulation of microbial community morphogene-
sis. Curr Opin Microbiol. 2014; 18:39–45. https://doi.org/10.1016/j.mib.2014.01.006 PMID: 24607644 24 / 24 PLOS ONE | https://doi.org/10.1371/journal.pone.0175197
April 12, 2017
|
https://openalex.org/W2015477762
|
https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0077799&type=printable
|
English
| null |
TLR 2 and 4 Responsiveness from Isolated Peripheral Blood Mononuclear Cells from Rats and Humans as Potential Chronic Pain Biomarkers
|
PloS one
| 2,013
|
cc-by
| 15,589
|
Abstract Copyright: 2013 Kwok et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: The study was funded by the Pain and Anaesthesia Research Clinic, University of Adelaide and was supported by Grant Number [DP110100297] from
Australian Research Council (ARC). Its contents are solely the responsibility of the authors and the funders had no role in study design, date collection and
analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: yuen.kwok@adelaide.edu.au Yuen H. Kwok1*, Jonathan Tuke2, Lauren L. Nicotra1, Peter M. Grace1,3, Paul E. Rolan1,4,5,
Mark R. Hutchinson3,6 1 Discipline of Pharmacology, School of Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia, 2 School of Mathematical Sciences, University of
Adelaide, Adelaide, South Australia, Australia, 3 Department of Psychology and The Center for Neuroscience, University of Colorado at Boulder, Boulder, Colorado, United
States of America, 4 Pain and Anaesthesia Research Clinic, University of Adelaide, Adelaide, South Australia, Australia, 5 Pain Management Unit, Royal Adelaide Hospital,
Adelaide, South Australia, Australia, 6 Discipline of Physiology, School of Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia Yuen H. Kwok1*, Jonathan Tuke2, Lauren L. Nicotra1, Peter M. Grace1,3, Paul E. Rolan1,4,5,
Mark R Hutchinson3,6 Yuen H. Kwok1*, Jonathan Tuke2, Lauren L. Nicotra1, Peter M. Grace1,3, Paul E. Rola
Mark R. Hutchinson3,6 Abstract Background: Chronic pain patients have increased peripheral blood mononuclear cell Interkeukin-1b production following
TLR2 and TLR4 simulation. Here we have used a human-to-rat and rat-to-human approach to further investigate whether
peripheral blood immune responses to TLR agonists might be suitable for development as possible systems biomarkers of
chronic pain in humans. Methods and Results: Study 1: using a graded model of chronic constriction injury in rats, behavioral allodynia was assessed
followed by in vitro quantification of TLR2 and TLR4 agonist-induced stimulation of IL-1b release by PBMCs and spinal cord
tissues (n = 42; 6 rats per group). Statistical models were subsequently developed using the IL-1b responses, which
distinguished the pain/no pain states and predicted the degree of allodynia. Study 2: the rat-derived statistical models were
tested to assess their predictive utility in determining the pain status of a published human cohort that consists of a
heterogeneous clinical pain population (n = 19) and a pain-free population (n = 11). The predictive ability of one of the rat
models was able to distinguish pain patients from controls with a ROC AUC of 0.94. The rat model was used to predict the
presence of pain in a new chronic pain cohort and was able to accurately predict the presence of pain in 28 out of the 34
chronic pain participants. Conclusions: These clinical findings confirm our previous discoveries of the involvement of the peripheral immune system
in chronic pain. Given that these findings are reflected in the prospective graded rat data, it suggests that the TLR response
from peripheral blood and spinal cord were related to pain and these clinical findings do indeed act as system biomarkers
for the chronic pain state. Hence, they provide additional impetus to the neuroimmune interaction to be a drug target for
chronic pain. Citation: Kwok YH, Tuke J, Nicotra LL, Grace PM, Rolan PE, et al. (2013) TLR 2 and 4 Responsiveness from Isolated Peripheral Blood Mononuclear Cells from Rats
and Humans as Potential Chronic Pain Biomarkers. PLoS ONE 8(10): e77799. doi:10.1371/journal.pone.0077799 Editor: Theodore John Price, University of Arizona, United States of America Received March 21, 2013; Accepted September 4, 2013; Published October 30, 2013 Copyright: 2013 Kwok et al. This is an open-access article distributed under the terms of the Creative Commons Attribut
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. October 2013 | Volume 8 | Issue 10 | e77799 Introduction Log10 (milligrams610) hair stiffness ranged from 3.61
(0.407 g) to 5.18 (15.136 g). The behavioral responses were used
to
calculate
the
50%
paw
withdrawal
threshold
(absolute
threshold), by fitting a Gaussian integral psychometric function
using a maximum-likelihood fitting method using the program
PsychoFit [24]. This fitting method allows parametric analyses that
otherwise would not be appropriate. Behavioral testing: von frey test. Rats were habituated for
at least three sessions (60 min) to the test environment prior to von
Frey testing. Testing was performed blinded with respect to the
experimental group. The von Frey test was performed within the
sciatic innervation area of the hind paw. Assessments were at
baseline, PO day 3, 7, 10 and day of cull and the development of
allodynia was assessed. Animals were followed to at least PO day
18 to ensure the neuropathic pain was well established. A
logarithmic series of ten calibrated Semmes-Weinstein monofila-
ments (von Frey hairs; Stoelting, Wood Dale, IL, USA) were
applied randomly to the left hind paw to determine the stimulus
intensity threshold stiffness required to elicit a paw withdrawal
response. Log10 (milligrams610) hair stiffness ranged from 3.61
(0.407 g) to 5.18 (15.136 g). The behavioral responses were used
to
calculate
the
50%
paw
withdrawal
threshold
(absolute
threshold), by fitting a Gaussian integral psychometric function
using a maximum-likelihood fitting method using the program
PsychoFit [24]. This fitting method allows parametric analyses that
otherwise would not be appropriate. However, given the cross-sectional nature of the human data
which hinders cause-and-effect analysis, we have sought whether
similar findings occur in a prospective graded animal model to
support that interpretation that this biomarkers lie on the causal
pathway rather than being bystander effects. Additionally we have
sought whether a biomarker panel based on TLR-induced IL-1b
production by PBMCs can distinguish pain from non-pain states in
two
separate
clinical
pain
populations
(medication
overuse
headache and sciatica) to explore potential clinical utility. Study 1: Graded Chronic Constriction Injury Surgery and
Sample Preparation Animals. Pathogen-free adult male Sprague–Dawley rats
(300–350 g; University of Adelaide, Laboratory Animal Services,
Waite Campus, Urrbrae, Australia) were used in all experiments. Rats were housed in a temperature-controlled (18–21uC) and
light-controlled (12 h light/dark cycle; lights on at 07:00 h) rooms
with standard rodent chow and water available ad libitum. Animals
were habituated to the holding facility for 1 week prior to
experimentation. All procedures were approved by the Animal
Ethics Committee of the University of Adelaide and were
conducted in accordance with the NHMRC Australian Code of
Practice for the Care and Use of Animals for Scientific Purposes. Stimulation of rat peripheral blood mononuclear cells
(PBMCs) and plasma collection. PBMCs were isolated using
Optiprep Sigma-Aldrich (Castle Hill, NSW, Australia) as directed
by the manufacturer using the mixer flotation method. Plasma was
also collected and stored at 270uC until the ELISA. Isolated cells
were diluted to 16106 cells?ml21 in enriched RPMI 1640 (10%
fetal calf serum and 1% penicillin) and plated into 96 well plates
(Nunc, Roskilde, Denmark) (100 ml per well). When insufficient
cells were obtained (5 rats), data were adjusted to 16106 cells (by
multiplication of the factor to obtain a response for IL-1b 16106
cells). A range of concentrations was added into the wells, TLR2
agonist (Pam3CSK4) from 10 ng?ml21 to 1 mg?ml21 and TLR4
agonist (LPS) from 10 ng?ml21 to 10 mg?ml21. Control wells Surgery. A graded neuropathic pain model, the ‘‘Grace
model’’ was used [22]. Surgery was conducted under isofluorane
(3% oxygen) anaesthesia. Briefly, the sciatic nerve was exposed at
the mid-thigh level of the left leg as previously described [23]. Between zero and 4 sterile chromic gut sutures (cuticular 4–0
chromic gut, FS-2; Ethicon, Somerville, NJ, USA) were loosely
tied around the gently isolated sciatic nerve to produce varying
degrees of allodynia. Once the superficial muscle overlying the
nerve was sutured, the animals had varying numbers of chromic
gut suture (equivalent length) placed in the subcutaneous space. For sham treatment, the sciatic nerve was identically exposed and
isolated but not tied. Animals were monitored postoperative (PO) Surgery. A graded neuropathic pain model, the ‘‘Grace
model’’ was used [22]. Surgery was conducted under isofluorane
(3% oxygen) anaesthesia. Briefly, the sciatic nerve was exposed at
the mid-thigh level of the left leg as previously described [23]. Introduction The
sciatic nerve was loosely ligated with chromic gut sutures, with the
number of perineural sutures indicated by the designation N0, N1,
N2 or N4. Additional pieces of chromic gut designated S4, S3, S2
or S0 respectively were also placed in the subcutaneous space, to
keep the total number of ligatures to 4, in order to keep the non-
specific immunological stimulus constant between the groups. This
model has been shown to produce graded neuropathic pain in
relation to the number of ligatures around the nerve. Two
additional groups (N1S0 and N2S0) with only ligatures to the
sciatic nerve were also introduced to examine only neuronal
insults. For the sham control the nerve was isolated but there was
no exposure to chromic gut. N0S4 was a control group for the
presence of chromic gut. The experimental groups (6 rats/group)
were N0S0 (sham control), N0S4, N1S0, N1S3, N2S0, N2S2 and
N4S0. A key mediator in the initiation of proinflammatory glial
reactivity associated with chronic pain is Toll Like Receptors
(TLRs). TLRs are an innate immune receptor family that
recognize danger-associated molecular patterns (DAMP) and
pathogen-associated molecular patterns [17]. Activation of TLRs
causes the production of pro-inflammatory mediators such as pro-
inflammatory cytokines (such as IL-1b) [9]. It is clear from
preclinical models that glia assume a proinflammatory reactive
state following activation by TLRs and that blockade of glial TLRs
significantly reduces experimentally induced neuropathic pain
[18–20]. Interestingly, we have recently demonstrated that in
chronic
pain
patients,
peripheral
blood
mononuclear
cells
(PBMCs) also have increased TLR2 and TLR4 responsiveness
compared with pain-free participants [21], suggesting that this
could be a potential pain biomarker. Behavioral testing: von frey test. Rats were habituated for
at least three sessions (60 min) to the test environment prior to von
Frey testing. Testing was performed blinded with respect to the
experimental group. The von Frey test was performed within the
sciatic innervation area of the hind paw. Assessments were at
baseline, PO day 3, 7, 10 and day of cull and the development of
allodynia was assessed. Animals were followed to at least PO day
18 to ensure the neuropathic pain was well established. A
logarithmic series of ten calibrated Semmes-Weinstein monofila-
ments (von Frey hairs; Stoelting, Wood Dale, IL, USA) were
applied randomly to the left hind paw to determine the stimulus
intensity threshold stiffness required to elicit a paw withdrawal
response. Introduction potential for improving translational success in pain research. Additionally, practical human pain biomarkers have potential uses
in enriching clinical trial populations, assisting in the selection of
patient treatment and monitoring treatment efficacy [2]. Pain as defined by the International Association for the Study of
Pain is an unpleasant sensory and emotional experience associated
with actual or potential tissue damage, or described in terms of
such damage. Pain is a subjective experience, and hence it is
conventionally assessed by patient reports, sometimes with added
rating scales. Preclinical animal pain research cannot use such
measures, but instead relies on behavioral responses to infer the
pain experience. There is a large failure rate in clinical translation
of therapies that are efficacious in standard preclinical animal
studies, possibly in part because of these different assessments [1]. Biomarkers that reflect pain biology and which could be used in
both preclinical animal and clinical human studies have the Development of pain biomarkers is problematic because of
difficulty in accessing the central nervous system (CNS) where the
chronic pain pathology likely resides. Although neuroimaging has
emerged as a potential biomarker for chronic pain, by providing
‘‘pain signatures’’ of the brain [3–6], there are several limitations
to its usage [7]. Instead, we have sought evidence that peripheral
tissues reflect functional changes of the CNS and hence have the
potential to be accessible human pain biomarkers. October 2013 | Volume 8 | Issue 10 | e77799 1 PLOS ONE | www.plosone.org TLR Responsiveness as Potential Pain Biomarker until fully ambulatory prior to the return of their cage and checked
daily for signs of infection. No such cases occurred in this study. Over the past 20 years substantial evidence has accumulated
indicating the involvement of non-neuronal cells playing a pivotal
role in chronic pain. In particular, the immunocompetent cells of
the CNS, glia, respond to pain signals releasing additional pro-
nociceptive proinflammatory mediators that in turn sensitize
neighboring neurons and glia facilitating the heightened pain state
[8–12]. Interestingly, this research points to attenuating proin-
flammatory glial activation is a promising new target for the
treatment of neuropathic pain, as drugs that attenuate pro-
inflammatory glial activation results in a reduction in allodynia
[13–16]. Experimental groups and design. Experimental groups
used in the Grace model were also selected in this study. Materials and Methods Peripheral blood and spinal cord collection. On the day
of cull (at least PO 18 day), rats were anesthetized with sodium
pentobarbital and blood (approximately 7 mL) was collected via
cardiac puncture into tubes containing EDTA. The rat was then
transcardially perfused with 15 ml of chilled 0.9% isotonic saline
and the lumbar spinal cord was quickly removed and dissected
into 3 equal lengths. The isolated spinal cord was incubated for
20 h at 37uC, 5% CO2 in a humidified environment (Thermoline
Scientific, Australia). Added to the incubation medium were
either: 10 mg/mL of TLR2 agonist synthetic triacylated lipopro-
tein (Pam3CSK4) or 10 mg/mL of TLR4 agonist lipopolysaccha-
ride (LPS) from Sigma-Aldrich (Castle Hill, NSW, Australia) or
RPMI medium only (control). Study 1: Graded Chronic Constriction Injury Surgery and
Sample Preparation TLR Responsiveness as Potential Pain Biomarker (consisted of participants from a previous study [21]) and an
expanded cohort. minus the TLR agonist were also included. Plates were incubated
for 20 h at 37uC, 5% CO2 in a humidified environment
(Thermoline Scientific, Australia). The published cohort consisted of chronic pain participants and
pain-free participants. Chronic pain participants had to experience
pain at least five days a week and for at least 3 months. The pain-
free participants had no clinically significant chronic pain and
were not taking opioids or other analgesics. The expanded cohort
consisted of mainly unilateral sciatica and medication-overuse
headache participants. Unilateral sciatica participants had to
experience pain at least five days a week and for at least 3 months. For the medication-overuse headache participants, the inclusion
criteria included regular use for at least 3 months of opioid-
containing analgesics (10$ days per month) headache present on
at least 15 days/month (for at least 2 months), headache developed
or markedly worsened during medication-overuse and primary
indication for analgesics is a headache disorder. Spinal cord sample preparation. Briefly, after 20 h of
incubation the supernatant of the spinal cord was stored at 280uC
until assay. The spinal cord sections were removed and sonicated
using a Labsonic 1510 probe sonicator (B. BRAUN, Melsungen,
Germany)
in
ice-cold
extraction
buffer
containing
Iscove’s
medium with 5% FCS and a cocktail enzyme inhibitor (including:
100 mM amino-n-caproic acid, 10 mM EDTA, 5 mM benzami-
dine-HCL, and 0.2 mM phenylmethylsulfonyl fluoride) all ob-
tained from Sigma-Aldrich (Castle Hill, NSW, Australia). Soni-
cated samples were centrifuged with the supernatant and stored at
270uC until assay. Spinal cord sample preparation. Briefly, after 20 h of
incubation the supernatant of the spinal cord was stored at 280uC
until assay. The spinal cord sections were removed and sonicated
using a Labsonic 1510 probe sonicator (B. BRAUN, Melsungen,
Germany)
in
ice-cold
extraction
buffer
containing
Iscove’s
medium with 5% FCS and a cocktail enzyme inhibitor (including:
100 mM amino-n-caproic acid, 10 mM EDTA, 5 mM benzami-
dine-HCL, and 0.2 mM phenylmethylsulfonyl fluoride) all ob-
tained from Sigma-Aldrich (Castle Hill, NSW, Australia). Soni-
cated samples were centrifuged with the supernatant and stored at
270uC until assay. Study 1: Graded Chronic Constriction Injury Surgery and
Sample Preparation Between zero and 4 sterile chromic gut sutures (cuticular 4–0
chromic gut, FS-2; Ethicon, Somerville, NJ, USA) were loosely
tied around the gently isolated sciatic nerve to produce varying
degrees of allodynia. Once the superficial muscle overlying the
nerve was sutured, the animals had varying numbers of chromic
gut suture (equivalent length) placed in the subcutaneous space. For sham treatment, the sciatic nerve was identically exposed and
isolated but not tied. Animals were monitored postoperative (PO) October 2013 | Volume 8 | Issue 10 | e77799 2 PLOS ONE | www.plosone.org TLR Responsiveness as Potential Pain Biomarker Study 2: Chronic Pain and Pain-free Participants There was no minimum pain score for eligibility. Chronic pain
patients from both cohorts could be taking ongoing opioid therapy
or not on any chronic opioid therapy. For all participants the key
inclusion criteria were the following: aged between 18 and 65
years, be in good general health (other than chronic pain patients)
without clinically significant renal, hepatic, cardiac or other
diseases. Key exclusion criteria were: use of any immunosuppres-
sant drugs (e.g. azathioprine); presence of an active inflammatory
process; a clinically significant infection in the previous 4 weeks; a
positive urine screen for illicit drugs (except for prescribed opioids),
pregnancy and/or lactation, and have a known history of hepatitis
B, C or HIV. Study participants. The data presented here was obtained
from 1 published study [21] and 2 unpublished clinical studies. Ethical approval was obtained from the Human Research Ethics
Committee of the Royal Adelaide Hospital, Adelaide, South
Australia. All studies were conducted at the Pain and Anaesthesia
Research Clinic (PARC), Royal Adelaide Hospital, Adelaide,
Australia. All participants gave written informed consent to participate
after a detailed oral explanation of the study. All participants were
paid for their inconvenience upon completion of the study. Chronic pain patients were recruited from the PARC volunteer
database, by public advertisements and from a pain management
unit. Healthy participants were recruited from the PARC’s healthy
participant database. Sixty-four participants were recruited and
participants were divided into 2 cohorts: published cohort Human blood collection and PBMCs isolation. On the
study day, information on pain history and medication use was
recorded. Twenty-seven ml of blood were collected into tubes
containing EDTA and the same procedure mentioned previously Figure 1. Overview of the generation of models in post graded CCI rats. doi:10.1371/journal.pone.0077799.g001
PLOS ONE |
l
3
O
b
2013 | V l
8 | I
10 |
7779 October 2013 | Volume 8 | Issue 10 | e77799 October 2013 | Volume 8 | Issue 10 | e77799 3 TLR Responsiveness as Potential Pain Biomarker in ‘‘Stimulation of rat PBMCs and plasma collection’’ was
performed. Sufficient cells were obtained from all participants
and plasma was not collected in humans. A range of concentra-
tions of TLR agonists were added into the wells in triplicate,
Pam3CSK4 from 13 pg?ml21 to 1 mg?ml21 (Sigma) and LPS from
6 pg?ml21 to 10 mg?ml21 (Sigma). Control wells minus the TLR
agonist were also included. divided into ‘‘Neuronal and subcutaneous’’ (N0S0, N0S4,
N1S3, N2S2 and N4S0) and ‘‘Neuronal’’ (N0S0, N1S0, N2S0
and N4S0) groups. Within the group, the output variables were
further divided into the 5 different subsets as mentioned above. Best model A selection: To predict the presence of
pain. N0S0
and
N0S4
were
experimental
groups
which
considered to have no pain (assigned as 0) because on the day of
cull the behavior score indicated there were no group differences
between N0S0 (sham) and N0S4. The 5 experimental groups
considered to have pain were assigned as 1 and consists of N1S0,
N1S3, N2S0, N2S2 and N4S0 (see Figure 1). The glm function
was used to predict the presence of pain for the following datasets
and subsets from all experimental groups: Best model A selection: To predict the presence of
pain. N0S0
and
N0S4
were
experimental
groups
which
considered to have no pain (assigned as 0) because on the day of
cull the behavior score indicated there were no group differences
between N0S0 (sham) and N0S4. The 5 experimental groups
considered to have pain were assigned as 1 and consists of N1S0,
N1S3, N2S0, N2S2 and N4S0 (see Figure 1). The glm function
was used to predict the presence of pain for the following datasets
and subsets from all experimental groups: N All dataset and the following 5 subsets: Peripheral, Central,
Basal, TLR2 and TLR4 A Pearson correlation was chosen to determine the relationship
between the actual von Frey score and the data predicted by the
refined model. The adjusted R-square was used as it takes into
account the number of variables introduced to the refined model. One-way ANOVA was used to compare the model generated
from the All dataset with the 5 subsets (see Figure 2) to determine
which models is a better predictor of the severity of allodynia. p
y
y
The same process was repeated with the Neuronal and
subcutaneous and Neuronal only experimental groups and
their corresponding 5 subsets (e.g. Peripheral). The glm function assesses how much each output variable
contributes to a response; the responses in question were (A) pain,
(B) von Frey score and (C) spinal cord IL-1b output (Figure 1). The
stepAIC function was used to refine the model by identifying
specific output variables that contributed the most to the model
and removed others that added no value to the model. Best model C selection: Prediction of IL-1b central output
by models generated from peripheral outputs. The glm
function and the stepAIC function were used to generate the
refined model to predict the basal spinal cord supernatant IL-1b
with output variables obtained from the Peripheral subset (from
All
and
for
Neuronal and subcutaneous
experimental
groups). A Pearson correlation was used to determine the
relationship between the predicted values (from the refined model)
with the actual IL-1b released from the basal spinal cord
supernatant. The adjusted R-square was used and the same
procedure was used to generate the model to predict the IL-1b
released from the lumbar spinal cord supernatant (post TLR2 and
TLR4) and the lumbar spinal cord (basal, post TLR2 and TLR4)
response. Grouping of output variables. To further dissect which
output variables were needed to create the best model to predict
the presence and severity of allodynia. The output variables were
divided according to anatomical locations and by stimulations as
outlined in Figure 2. ‘‘Dataset’’ contained all output variables
collected from all anatomical locations and from all stimulations. Whereas subsets contained specific output variables group from
either specific location (e.g. Central subset only consist output
variables obtained from central region) or from specific stimulation
(e.g. TLR2 subset consist output variables stimulated only with
TLR2 agonists). The 5 subsets were Peripheral, Central, Basal,
TLR2 and TLR4. N All dataset and the following 5 subsets: Peripheral, Central,
Basal, TLR2 and TLR4 In
order to determine whether models constructed with the collected
output variables allow: (A) categorization of the pain/no pain
states in rats (B) the detection of the allodynia severity in rats (C)
whether in rats, central outputs can be predicted with peripheral
outputs. The generalized linear model (glm) and the R function
stepAIC were used to generate models. StepAIC function [25]
performs
stepwise
model
selection
(backward
and
forward
selection) using the Akaike information criterion (AIC) as a
variable selection criterion. The functions glm and stepAIC are
both found in the Modern Applied Statistics with S (MASS)
package (From the statistical software R; www.r-project.org). The glm function assesses how much each output variable
contributes to a response; the responses in question were (A) pain,
(B) von Frey score and (C) spinal cord IL-1b output (Figure 1). The
stepAIC function was used to refine the model by identifying
specific output variables that contributed the most to the model
and removed others that added no value to the model. N All dataset and the following 5 subsets: Peripheral, Central,
Basal, TLR2 and TLR4 N All dataset and the following 5 subsets: Peripheral, Central,
Basal, TLR2 and TLR4 N All dataset and the following 5 subsets: Peripheral, Central,
Basal, TLR2 and TLR4 The stepAIC function was performed to select output variables
that contributed significantly to the refined model. Receiver
Operating Characteristic (ROC) curves were generated from the
refined model and the area under the curve was calculated. One-
way ANOVA was used to compare the model generated from the
All dataset with the 5 subsets (see Figure 1). The same process was repeated with the Neuronal and
subcutaneous and Neuronal only experimental groups and
their corresponding 5 subsets (e.g. Peripheral). Study 1 Development of Models from Peripheral and
Central Obtained IL-1b Released from Post Graded CCI
Rats Best model B selection: To predict the severity of
allodynia. The glm function was used to predict the severity
of allodynia (von Frey score at day of cull) and the stepAIC
function
was
used
to
identify
the
refined
model
for
All
experimental groups: Best model B selection: To predict the severity of
allodynia. The glm function was used to predict the severity
of allodynia (von Frey score at day of cull) and the stepAIC
function
was
used
to
identify
the
refined
model
for
All
experimental groups: Overview of modeling. The overview of the modeling is
summarize in Figure 1. All the collected outputs from the rat
(presented in Table 1 and 2.) were imported into the statistical
computing environment R (R Development Core Team, 2007). In
order to determine whether models constructed with the collected
output variables allow: (A) categorization of the pain/no pain
states in rats (B) the detection of the allodynia severity in rats (C)
whether in rats, central outputs can be predicted with peripheral
outputs. The generalized linear model (glm) and the R function
stepAIC were used to generate models. StepAIC function [25]
performs
stepwise
model
selection
(backward
and
forward
selection) using the Akaike information criterion (AIC) as a
variable selection criterion. The functions glm and stepAIC are
both found in the Modern Applied Statistics with S (MASS)
package (From the statistical software R; www.r-project.org). Overview of modeling. The overview of the modeling is
summarize in Figure 1. All the collected outputs from the rat
(presented in Table 1 and 2.) were imported into the statistical
computing environment R (R Development Core Team, 2007). Rat and Human IL-1b Assay b
y
IL-1b level was determined by a commercially available ELISA
(rat IL-1b ELISA; eBioscience, San Diego, CA and for human IL-
1b ELISA; BD Bioscience, Australia). For the rat’s ELISA kit, the
manufacturer’s instructions were modified by extending the
standard curve from 39 pg/mL to 5 pg/mL so that lower
concentration of IL-1b could be detected. The extended standard
curve was accepted for each ELISA when the R-square (goodness
of fit) was above 0.99. For the human’s ELISA kit the IL-1b levels
were determined according to the manufacturer’s instructions. UV
absorbance was quantified on a BMG PolarStar microplate reader
(BMG Labtechnologies, Offenburg, Germany) at 450 nm with
absorbance
at
570 nm
subtracted. The
modified
limit
of
quantification of 5 pg?ml21 was used for the rat’s ELISA kit and
for the human’s ELISA kit the manufacturer’s limit of quantifi-
cation of 0.8 pg?ml21 was used. PLOS ONE | www.plosone.org N All dataset and the following 5 subsets: Peripheral, Central,
Basal, TLR2 and TLR4 Cell counts were
normalized by log transformation and analyzed using one-way ANOVA followed by Bonferroni. It should be noted the following rats did not have enough PBMCs
therefore the rat’s PBMCs reactivity were normalize to 10‘6 cells in the following rats: 2 rats from N0S0, 3 rats from N1S0 and 1 rat from N2S0. Higher cell counts were
detected in experimental group N1S3 vs. N0S0 (indicated with *, P = 0.049) and N1S0 vs. N1S3 (Indicated with #, P = 0.035). Data (except cell count) were analyzed using
Kruskal-Wallis one-way ANOVA. doi:10.1371/journal.pone.0077799.t001 Data are presented as mean 6 SEM. Peripheral blood mononuclear cells (PBMCs) were isolated from 41 rats and stimulated with LPS (10 ng?ml21 to 10 mg?ml21) and
with Pam3CSK4 (from 10 ng?ml21 to 1 mg?ml21) for 20 h. No PBMCs could be obtained from 1 rat in N2S0. Plasma were collected from 42 rats. Cell counts were
normalized by log transformation and analyzed using one-way ANOVA followed by Bonferroni. It should be noted the following rats did not have enough PBMCs
therefore the rat’s PBMCs reactivity were normalize to 10‘6 cells in the following rats: 2 rats from N0S0, 3 rats from N1S0 and 1 rat from N2S0. Higher cell counts were
detected in experimental group N1S3 vs. N0S0 (indicated with *, P = 0.049) and N1S0 vs. N1S3 (Indicated with #, P = 0.035). Data (except cell count) were analyzed using
Kruskal-Wallis one-way ANOVA. doi:10.1371/journal.pone.0077799.t001 doi:10.1371/journal.pone.0077799.t001 collected outputs (Table 3) from the ‘‘published cohort’’ [21] with
the use of the glm and stepAIC function. Study 2 Development of Model D to Predict the Presence
of Pain in Humans (Chronic Pain and Pain-free
Participants) and Compare Models Generated from Study Comparison of different models developed from rats and
humans. ‘‘Model rat to human’’ used the output variables
selected by the Peripheral subset obtained from rats (from all
experimental groups) and applied to the clinical data obtained
from the ‘‘published cohort’’ [21] (listed in Table 3). A ROC curve
was generated from both models and the area under the curve was
calculated. One-way ANOVA was used to compare the models The overview of the modeling is summarized in Figure 3. The
chronic pain patients in the published cohort [21] were the group
considered to have pain therefore assigned as 1. The pain-free
participants were considered to have no pain hence assigned as 0. N All dataset and the following 5 subsets: Peripheral, Central,
Basal, TLR2 and TLR4 To explore the interaction between the effects of nerve alone
and combined suture placement, experimental groups were also October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org 4 TLR Responsiveness as Potential Pain Biomarker Table 1. Summary of variables collected from rats post CCI in the periphery region. Variables
P- value
Peripheral (PBMCs)
N0S0
N0S4
N1S3
N2S2
N4S0
N1S0
N2S0
Non-stimulated
Plasma IL-1b (pg/mL)
1.760.4
2.760.7
1.460.4
3.360.3
1065.3
460.3
5.561.7
0.03
Cell count
(‘6 cells/mL)
3.461.8*
7.461.5
9.262.8*#
3.560.8
5.961
1.860. 7#
5.662.1
0.004
Cells IL-1b (pg/mL)
6.361.7
4.960.6
5.761
7.562.8
4.660.4
4.861.1
4.760.4
1
Pam3CSK4stimulated (TLR2)
IL-1b (pg/mL)
Minimum
2.360.7
3.160.9
2.560.4
3.660.5
2.260.7
3.760.7
3.860.7
0.5
Maximum
8.461.8
13.964
14.563.2
12.763.5
9.561.4
8.662.4
10.562.3
0.7
Slope
20.660.5 22.161.7 1.161.7
0.360.9
20.160.8 20.0960.6
21.961.4
0.02
Intercept
5.461.1
8.762.6
5.860.6
761
5.660.5
5.760.9
6.461.04
0.4
LPS stimulated (TLR4) IL-1b
(pg/mL)
Minimum
1263.3
14.566.1
26.4610.2
23.667.2
1663.1
12.864.7
1667.3
0.2
Maximum
24.566.8
31.4610.6 70.5639.7
65.4619.1
27.765.8
41.5619
45.3625.3
0.7
Slope
3.761.8
2.862
217.4617.5 11.867.5
3.261.9
9.264.8
8.969
0.5
Intercept
13.763
20.166.8
60.7635.8
28.667.7
18.263.1
16.366.1
18.965.6
0.8
Control
Neuronal and Subcutaneous
Neuronal
Experimental Groups
Data are presented as mean 6 SEM. Peripheral blood mononuclear cells (PBMCs) were isolated from 41 rats and stimulated with LPS (10 ng?ml21 to 10 mg?ml21) and
with Pam3CSK4 (from 10 ng?ml21 to 1 mg?ml21) for 20 h. No PBMCs could be obtained from 1 rat in N2S0. Plasma were collected from 42 rats. Cell counts were
normalized by log transformation and analyzed using one-way ANOVA followed by Bonferroni. It should be noted the following rats did not have enough PBMCs
therefore the rat’s PBMCs reactivity were normalize to 10‘6 cells in the following rats: 2 rats from N0S0, 3 rats from N1S0 and 1 rat from N2S0. Higher cell counts were
detected in experimental group N1S3 vs. N0S0 (indicated with *, P = 0.049) and N1S0 vs. N1S3 (Indicated with #, P = 0.035). Data (except cell count) were analyzed using
Kruskal-Wallis one-way ANOVA. doi:10.1371/journal.pone.0077799.t001 Data are presented as mean 6 SEM. Peripheral blood mononuclear cells (PBMCs) were isolated from 41 rats and stimulated with LPS (10 ng?ml21 to 10 mg?ml21) and
with Pam3CSK4 (from 10 ng?ml21 to 1 mg?ml21) for 20 h. No PBMCs could be obtained from 1 rat in N2S0. Plasma were collected from 42 rats. N All dataset and the following 5 subsets: Peripheral, Central,
Basal, TLR2 and TLR4 Model rat to human: ‘‘Model rat’’ was used however the rat
data was replaced with human data (‘‘published cohort’’). II. Model rat to human: ‘‘Model rat’’ was used however the rat
data was replaced with human data (‘‘published cohort’’). generated from rats and from humans to predict the presence of
pain. III. Model human: Model generated from the published cohort. N All dataset and the following 5 subsets: Peripheral, Central,
Basal, TLR2 and TLR4 The ‘‘Model human’’ was the refined model constructed from the Table 2. Summary of variables collected from rats post CCI in the central region. Table 2. Summary of variables collected from rats post CCI in the central region. Variables
P- value
Central (lumbar spinal cord)
N0S0
N0S4
N1S3
N2S2
N4S0
N1S0
N2S0
Non-stimulated IL-1b (pg/mL)
Spinal cord
supernatant
4.460.4
34.4624.9
5.160.8
9.362.9
10.465.1
16.567.5
7.361.9
0.7
Spinal cord
66.6611.4
60610.6
55.4615.2
50.4610.4
50.5610.9
50615.6
67.4614.2
0.8
Pam3CSK4stimulated (TLR2)
IL-1b (pg/mL)
Spinal cord
supernatant
5.260.6
7.161.5
6.161.4
762
661.3
9.262.7
6.761.5
0.9
Spinal cord
62612
42.662. 50.5612.2
64.4612.8
7967.2
64.8610.6
83.5613.1
0.2
LPS stimulated (TLR4) IL-1b
(pg/mL)
Spinal cord
supernatant
6.860.7
7.762.5
11.164.6
961.8
761.3
11.865.5
6.260.8
0.9
Spinal cord
48.567.1
50.367.1
61.6610.3
81.8616.9
51.768.2
67.2611.8
66.368.9
0.6
Control
Neuronal and Subcutaneous
Neuronal
Experimental Groups
Data are presented as mean 6 SEM. Spinal cord sections were collected from 42 rats and stimulated with LPS at 100ug/mL and Pam3CSK4 at 100 ug/mL. Experimental
groups were analyzed using Kruskal-Wallis one-way ANOVA. doi:10.1371/journal.pone.0077799.t002 Data are presented as mean 6 SEM. Spinal cord sections were collected from 42 rats and stimulated with LPS at 100ug/mL and Pam3CSK4 at 100 ug/mL. Experimental
groups were analyzed using Kruskal-Wallis one-way ANOVA. doi:10.1371/journal.pone.0077799.t002 October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org PLOS ONE | www.plosone.org 5 TLR Responsiveness as Potential Pain Biomarker TLR Responsiveness as Potential Pain Biomarker Figure 2. The schematic representation of the breakdown of data according to anato
groups N0S0 and N0S4 are present in both ‘‘neuronal and subcutaneous’’ (italics) and in ‘‘neuro
doi:10.1371/journal.pone.0077799.g002 Figure 2. The schematic representation of the breakdown of data according to anatomical location and stimulations. Experimental
groups N0S0 and N0S4 are present in both ‘‘neuronal and subcutaneous’’ (italics) and in ‘‘neuronal’’ (underline). doi:10.1371/journal.pone.0077799.g002 Figure 2. The schematic representation of the breakdown of data according to anatomical location and stimulations. Experimental
groups N0S0 and N0S4 are present in both ‘‘neuronal and subcutaneous’’ (italics) and in ‘‘neuronal’’ (underline). doi:10.1371/journal.pone.0077799.g002 Figure 2. The schematic representation of the breakdown of data according to anato
groups N0S0 and N0S4 are present in both ‘‘neuronal and subcutaneous’’ (italics) and in ‘‘neuro
doi:10.1371/journal.pone.0077799.g002 Figure 2. The schematic representation of the breakdown of data according to anatomical location and stimulations. Experimental
groups N0S0 and N0S4 are present in both ‘‘neuronal and subcutaneous’’ (italics) and in ‘‘neuronal’’ (underline). doi:10.1371/journal.pone.0077799.g002 II. Statistical Analyses Peripheral blood mononuclear cells (PBMC) were isolated from 64 participants and were stimulated with LPS (6 pg?ml21 to
10 mg?ml21) and with Pam3CSK4 (from 13 pg?ml21 to 1 mg?ml21) for 20 h. doi:10.1371/journal.pone.0077799.t003 Data are presented as mean 6 SEM. Peripheral blood mononuclear cells (PBMC) were isolated from 64 participants and were stimulated with LPS (6 pg?ml21 to
10 mg?ml21) and with Pam3CSK4 (from 13 pg?ml21 to 1 mg?ml21) for 20 h. doi:10.1371/journal.pone.0077799.t003 effect was observed (P,0.0001) and Bonferroni post hoc test showed
N1S3 (P = 0.03), N2S0 (P = 0.0002), N2S2 (P = 0.0002) and N4S0
(P = 0.0002) having significantly greater allodynia when compared
to sham N0S0. The following experimental groups: N2S0
(P = 0.02), N2S2 (P = 0.02) and N4S0 (P = 0.02) were also found
to have significantly greater allodynia scores than N0S4 (no nerve
ligatures) confirming the important component of nerve involve-
ment (Figure 4). cell count data was normalized by log transformation. Differences
between experimental groups in von Frey score and in vitro IL-1b
post TLR agonist were analyzed using repeated measures two-way
ANOVAs followed by Bonferroni post hoc test. The experimental
groups differences on the day of cull and the cell count was
analyzed with one-way ANOVA followed by Bonferroni post hoc
test. For the other variables: plasma, basal IL-1b level, TLR
agonist stimulated IL-1b curves (min, max, slope and intercept),
TLR agonist stimulated IL-1b from spinal cord the experimental
groups differences were calculated with Kruskal-Wallis one-way
ANOVA. IL-1b outputs (basal and stimulated) collected from rats
in central and peripheral regions did not differ between For study 2, the age difference between the chronic pain
participants (published and expanded cohort) and the pain-free
participants was analyzed using one-way ANOVA. The daily
morphine used and the duration of pain between the 2 chronic
pain
cohorts
was
analyzed
using
Mann-Whitney
test. To
determine the group differences between the new cohort of
chronic pain patients and pain-free participants, previously
published clinical data was used [21]. The concentration-response
curve for the TLR2 agonist was assessed using a sigmoidal
concentration response equation. For the TLR4 agonist concen-
tration-response, curve a modified biphasic curve as described
previously was used [21]. The F-tests were used to determine if the
best fit curves with the selected parameters (Emax, Emin and EC50)
differed, thus reflecting group differences in the IL-1b expressed
by PBMCs post TLR agonist stimulation. Figure 4. Statistical Analyses Allodynia quantification at day of cull (At least
postoperative day 18). Graded neuropathy was induced by varying
the number of chromic gut pieces ligating the nerve (N) and/or
distributed in the subcutaneous (S) compartments. The treatment
groups were N0S0, N0S4, N1S0, N1S3, N2S0, N2S2 and N4S0 (n = 6/
group). At baseline all rats responded very similarly and was not
included in the statistical analysis. A significant group effect was
observed at day of cull (P,0.0001) and with some of the experimental
groups (*P = 0.03, N0S0 vs. N1S3; **P = 0.0002, N0S0 vs. N2S0, N0S0 vs. N2S2, N0S0 vs. N4S0; #P = 0.02, N0S4 vs. N2S0, N0S4 vs. N2S2, N0S4 vs. N4S4). Error bars on graphs represent standard error of the mean and
significance is set at P,0.05. doi:10.1371/journal.pone.0077799.g004 For both studies, the concentration-response curves for the
TLR2 and TLR4 agonists obtained from rats and humans were
fitted by linear regression. The minimum, maximum, slope and
intercept were calculated from the curves obtained from each rat
group, chronic pain patients and pain-free participants. All
significance was set at P,0.05. Figure 4. Allodynia quantification at day of cull (At least
postoperative day 18). Graded neuropathy was induced by varying
the number of chromic gut pieces ligating the nerve (N) and/or
distributed in the subcutaneous (S) compartments. The treatment
groups were N0S0, N0S4, N1S0, N1S3, N2S0, N2S2 and N4S0 (n = 6/
group). At baseline all rats responded very similarly and was not
included in the statistical analysis. A significant group effect was
observed at day of cull (P,0.0001) and with some of the experimental
groups (*P = 0.03, N0S0 vs. N1S3; **P = 0.0002, N0S0 vs. N2S0, N0S0 vs. N2S2, N0S0 vs. N4S0; #P = 0.02, N0S4 vs. N2S0, N0S4 vs. N2S2, N0S4 vs. N4S4). Error bars on graphs represent standard error of the mean and
significance is set at P,0.05. d i 10 1371/j
l
0077799 004 Statistical Analyses The predict function in R was used to determine which of the
constructed models (see Figure 3 and also listed below) is the best
predictor of pain presence in the ‘‘expanded cohort’’ (all chronic
pain participants). Participant with the predicted score between 0
to 0.5 was considered to have no pain and score above 0.5 was
considered to have pain. Graphpad Prism version 6.0 for Windows (GraphPad Software,
San Diego California USA, www.graphpad.com) was used for
basic statistical analysis and correlation graphs unless otherwise
stated. Data were tested for normality with the D’Agostino-
Pearson omnibus normality test and when the data did not fit
normal distribution a non-parametric test was chosen instead. I. Model rat: The output variables were from the Peripheral
subset refined model obtained from rats and the data used in
this model was also from rats. I. Model rat: The output variables were from the Peripheral
subset refined model obtained from rats and the data used in
this model was also from rats. For study 1, data from the von Frey test were analyzed as the
interpolated 50% threshold (absolute threshold) in log base 10 of
stimulus intensity (monofilament stiffness in milligrams *10). The Figure 3. Overview of the generation and comparison of models generated from post graded CCI rats and humans (chronic pain
and pain-free participants). doi:10.1371/journal.pone.0077799.g003 Figure 3. Overview of the generation and comparison of models generated from post graded CCI rats and humans (chronic pain
and pain-free participants). doi:10.1371/journal.pone.0077799.g003 October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org 6 TLR Responsiveness as Potential Pain Biomarker Table 3. Summary of variables collected from humans in the periphery region. Variables
Published Cohort
Expanded Cohort
Chronic Pain
Pain-Free
Chronic Pain
Non-stimulated
Cell count (‘7)
1.160.09
160.12
1.260.07
Cells (pg/mL)
0.960.2
1.160.2
1263
Pam3CSK4 stimulated (TLR2) IL-1b (pg/mL)
Minimum
3.562.5
2.161.1
3068.2
Maximum
929.86164.4
162.6640.5
524.5693.9
Slope
155.4633.1
31.60614.2
65.75615.4
Intercept
677.56148.3
93.4619.3
361.7669.6
LPS stimulated (TLR4) IL-1b (pg/mL)
Minimum
107.6682
15.267.3
112.3637.3
Maximum
22316202.2
20086162
19756145.3
Slope
358.8640.1
289.2624.6
322.5651.1
Intercept
20656207.6
15306150.1
19306239.2
Data are presented as mean 6 SEM. Peripheral blood mononuclear cells (PBMC) were isolated from 64 participants and were stimulated with LPS (6 pg?ml21 to
10 mg?ml21) and with Pam3CSK4 (from 13 pg?ml21 to 1 mg?ml21) for 20 h. doi:10.1371/journal.pone.0077799.t003 Data are presented as mean 6 SEM. TLR Responsiveness as Potential Pain Biomarker The ROC AUC was 0.9 and the order of best to worse
predictor of pain of the other models collected from the other from the dataset and subsets are as follows: All.Basal.TLR2
and Peripheral.TLR4 (ROC AUC: 0.87.0.8.0.76.0. 61)
(Additional information can be found in Table S1 in File S1). ANOVA
analysis
revealed
the
model
generated
from
the
Complete dataset did not differ with the model collected from
the Peripheral (p = 0.09) but it was significantly different from
the models generated from output variables collected from
Central (p = 0.04), TLR2 (p = 0.02), TLR4 (p = 0.003) and
Basal (p = 0.01). subsets are as follows: Peripheral and Central.TLR2. TLR4. Basal (ROC AUC: 0.88.0.77.0.64.0.58) (Table S1
in File S1). ANOVA analysis revealed the model generated from
the All outputs variables did not differ with model collected from
Peripheral (p = 0.2), Central (p = 0.2), TLR2 (p = 0.2), TLR4
(p = 0.05) or Basal (p = 0.1). In all experimental groups Model B: A combination of all
outputs
best
predicted
the
severity
of
allodynia
in
rats. The combined output variables (include all regions and
stimulations) that best predicted the severity of allodynia was from In
neuronal
and
subcutaneous
experimental
groups
Model B: TLR2 outputs best predicted the severity of
allodynia in rats. The panel of output variables that best
predicted the severity of allodynia was from TLR2 IL-1b outputs Table 4. Best-fit logistic regression model results for the prediction of pain for rats post CCI. Experimental
Groups:
Dataset
Variables
Estimate SE
P
Null
deviance
df
Residual
deviance
df
AUC
ANOVA
All
Central
TLR4 stimulated supernatant of
spinal cord
0.21
0.12
0.07. 39.90
34
23.57
29
0.9
0.004
Non-stimulated supernatant of
spinal cord
20.052
0.052
0.31
TLR4 stimulated spinal cord
0.099
0.052
0.058
TLR2 stimulated spinal cord
0.067
0.038
0.078
Non-stimulated spinal cord
20.062
0.029
0.036
Neuronal and
subcutaneous
Complete
Peripheral non-stimulated plasma
0.78
0.60
0.19
31.76
23
16.76
18
0.9
–
Peripheral non-stimulated cells
20.31
0.23
0.17
Peripheral TLR4 stimulated min
0.10
0.059
0.085
Central TLR4 stimulated
spinal cord
0.070
0.056
0.21
Central non-stimulated
spinal cord
20.073
0.049
0.14
Neuronal
Complete
Peripheral non-stimulated cells
21.23
0.77
0.11
23.05
20
14.51
18
0.86
–
Peripheral TLR4 stimulated
intercept
0.43
0.31
0.17
Notes: Significant variables are shown in bold. The discrimination probabilities (D, area under ROC curve) are presented in the table. TLR Responsiveness as Potential Pain Biomarker ANOVA analysis revealed the model generated from all
outputs
was
significantly
different
from
the
Peripheral
(p = 0.004), TLR2 (p = 0.01), TLR4 (p = 0.003) and the Basal
(p = 0.01) subsets but it did not differ with Central (p = 0.09)
collected outputs. predictor of allodynia severity) Central.TLR2.Peripheral. Basal.TLR4 (adjusted R-square: 0.32 (P = 0.0035) .0.17
(P = 0.05) .0.17 (P = 0.11) .0.1 (NS P = 0.07) .0.0081, (NS
P = 0.37) (Additional information can be found in Table S2 in File
S1). ANOVA analysis revealed the model generated from all
outputs
was
significantly
different
from
the
Peripheral
(p = 0.004), TLR2 (p = 0.01), TLR4 (p = 0.003) and the Basal
(p = 0.01) subsets but it did not differ with Central (p = 0.09)
collected outputs. In all experimental groups Model A: Central outputs best
predicted the presence of pain in rats. The panel of output
variables that best predicted the presence of pain was from
Central region (Table 4). The area under the ROC curve (ROC
AUC) was 0.9 indicating a very good ability to determine the
presence of pain. The IL-1b released by the basal spinal cord
played a significant contribution in the model (P = 0.04). The
order of best to worse models for the predictor of pain collected In
neuronal
and
subcutaneous
experimental
groups
Model A: A combination of all outputs best predicted the
presence of pain in rats. The panel of output variables that
best predicted the presence of pain was from All output variables
(Table 4). The ROC AUC was 0.9 and the order of best to worse
predictor of pain of the other models collected from the other
subsets are as follows: Peripheral and Central.TLR2. TLR4. Basal (ROC AUC: 0.88.0.77.0.64.0.58) (Table S1
in File S1). ANOVA analysis revealed the model generated from
the All outputs variables did not differ with model collected from
Peripheral (p = 0.2), Central (p = 0.2), TLR2 (p = 0.2), TLR4
(p = 0.05) or Basal (p = 0.1). In
neuronal
and
subcutaneous
experimental
groups
Model A: A combination of all outputs best predicted the
presence of pain in rats. The panel of output variables that
best predicted the presence of pain was from All output variables
(Table 4). Results Study 1: Post Graded CCI Rat Model Study 1: Post Graded CCI Rat Model Rats developed allodynia after CCI surgery. At baseline
all rats had similar behavior scores revealed by one-way ANOVA
(NS, P = 0.8) (Figure 4). After CCI surgery, two-way ANOVA
revealed a significant effects of group (P,0.0001) and time
(P,0.0001) (data not shown). On the day of cull (at least PO day
18 to PO day 27), two-way ANOVA revealed a significant group October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org 7 TLR Responsiveness as Potential Pain Biomarker experimental groups. The basal cell level (un-stimulated) of
IL-1b expression was revealed by one-way ANOVA to be the
same for all 7 experimental groups (p = 1) (see Table 1). In contrast
to the previous human study, two-way ANOVA revealed there
were no significant group effect between all 7 experimental groups
post TLR2 (p = 0.9) or TLR4 (p = 0.1) agonist stimulation in the
isolated PBMCs but a significant concentration effects was found
for both TLR2 (p = 0.0002) and TLR4 (p = 0.001). No significant
group effect was found by the Kruskal-Wallis one-way ANOVA
for the lumbar spinal cord (Basal p = 0.8, Post TLR2 stimulated
p = 0.2 and Post TLR4 stimulated p = 0.6) or from the supernatant
(Basal p = 0.7, Post TLR2 stimulated p = 0.9 and Post TLR4
stimulated p = 0.9) showed in Table 2. All outputs (see Table 5). The actual von Frey score was
significantly
correlated
with
the
predicted
von
Frey
score
generated
from
a
panel
of
output
variables
(adjusted
R-
square = 0.44, P = 0.0044). The following output variables played
a significant contribution to the model: TLR2 stimulated PBMC
responses (max (P = 0.01), min (P = 0.01) and intercept (P = 0.008),
basal spinal cord (P = 0.007) and TLR2 stimulated spinal cord
(P = 0.003) responses. The order of the other models generated
from the different subsets are as follows: (from best to worse
predictor of allodynia severity) Central.TLR2.Peripheral.- All outputs (see Table 5). The actual von Frey score was
significantly
correlated
with
the
predicted
von
Frey
score
generated
from
a
panel
of
output
variables
(adjusted
R-
square = 0.44, P = 0.0044). The following output variables played
a significant contribution to the model: TLR2 stimulated PBMC
responses (max (P = 0.01), min (P = 0.01) and intercept (P = 0.008),
basal spinal cord (P = 0.007) and TLR2 stimulated spinal cord
(P = 0.003) responses. The order of the other models generated
from the different subsets are as follows: (from best to worse
predictor of allodynia severity) Central.TLR2.Peripheral.-
Basal.TLR4 (adjusted R-square: 0.32 (P = 0.0035) .0.17
(P = 0.05) .0.17 (P = 0.11) .0.1 (NS P = 0.07) .0.0081, (NS
P = 0.37) (Additional information can be found in Table S2 in File
S1). TLR Responsiveness as Potential Pain Biomarker The von Frey score was significantly correlated with
the variables from the TLR2 IL-1b outputs (adjusted R-square:
0.37, P = 0.02). Within the output variables selected, the following
outputs have significant contribution: TLR2 stimulated PBMC
(max (P = 0.03), intercept (P = 0.04)) and TLR2 stimulated spinal
cord (P = 0.01). The order of the other models collected from
different dataset and subsets are as follows: (from best to worse
predictor of allodynia severity) Central .Peripheral.Basa-
l.All.TLR4
(adjusted
R-square:
0.34
(P = 0.02)
.0.29
(P = 0.04) .0.23 (P = 0.04) .0.56 (NS P = 0.06).20.019 (NS
P = 0.5) (Table S2 in File S1). ANOVA analysis revealed the
model generated from All output variables was not significantly
different from the Peripheral (p = 0.15), Central (p = 0.19),
TLR2 (p = 0.2), TLR4 (p = 0.05) and Basal (p = 0.12) specific
output variables. as follows: Central and Basal.TLR2.Peripheral.TLR4
(ROC AUC: 0.76.0.66.0.63.0.6) (Table S1 in File S1). ANOVA analysis revealed the outputs generated from Periph-
eral (p = 0.009) and TLR2 (p = 0.006) were significantly different
from All output variables but not with Central (p = 0.16). The
ANOVA could not be calculated for the model generated from
TLR4 output variables owing to incompatibility of the models. (see Table 6). The von Frey score was significantly correlated with
the variables from the TLR2 IL-1b outputs (adjusted R-square:
0.37, P = 0.02). Within the output variables selected, the following
outputs have significant contribution: TLR2 stimulated PBMC
(max (P = 0.03), intercept (P = 0.04)) and TLR2 stimulated spinal
cord (P = 0.01). The order of the other models collected from
different dataset and subsets are as follows: (from best to worse
predictor of allodynia severity) Central .Peripheral.Basa-
l.All.TLR4
(adjusted
R-square:
0.34
(P = 0.02)
.0.29
(P = 0.04) .0.23 (P = 0.04) .0.56 (NS P = 0.06).20.019 (NS
P = 0.5) (Table S2 in File S1). ANOVA analysis revealed the
model generated from All output variables was not significantly
different from the Peripheral (p = 0.15), Central (p = 0.19),
TLR2 (p = 0.2), TLR4 (p = 0.05) and Basal (p = 0.12) specific
output variables. In neuronal experimental groups Model B: A combination
of all outputs best predicted the severity of allodynia in
rats. The output variables that best predicted the severity of
allodynia were from All output variables (see Table 7). TLR Responsiveness as Potential Pain Biomarker One-way ANOVA was used to
compare which subsets (Central/Peripheral/TLR2/TLR4 or Basal) when compare with all outputs is a better model. The residual deviance for the model includes predictor
variables, whereas the null deviance for the model does not. SE, standard error. doi:10.1371/journal.pone.0077799.t004 Table 4. Best-fit logistic regression model results for the prediction of pain for rats post CCI. Notes: Significant variables are shown in bold. The discrimination probabilities (D, area under ROC curve) are presented in the table. One-way ANOVA was used to
compare which subsets (Central/Peripheral/TLR2/TLR4 or Basal) when compare with all outputs is a better model. The residual deviance for the model includes predictor
variables, whereas the null deviance for the model does not. SE, standard error. doi:10.1371/journal.pone.0077799.t004 October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org PLOS ONE | www.plosone.org 8 TLR Responsiveness as Potential Pain Biomarker Table 5. Best-fit logistic regression model results for the prediction of the pain severity in rats post CCI in all experimental groups. Dataset
Variables
Estimate
SE
P
Null
deviance
df
Residual
deviance
df
Adjusted
R-square:
P-value
Complete
Peripheral non-stimulated cell count
21.9961028
1.3061028
0.14
5.42
34 2.15
24 0.44
0.0044
Peripheral non-stimulated plasma
21.2261022
8.8461023
0.18
Peripheral TLR4 stimulated min
1.5661022
8.6961023
0.086
Peripheral TLR4 stimulated intercept
28.1361023
4.8961023
0.11
Peripheral TLR4 stimulated slope
21.3761022
6.8061023
0.055
Peripheral TLR2 stimulated max
25.2961022
1.9161022
0.011
Peripheral TLR2 stimulated min
21.2561021
4.4661022
0.0099
Peripheral TLR2 stimulated intercept
1.1961021
4.1161022
0.0078
Central TLR2 stimulated spinal cord
27.7461023
2.3261023
0.0028
Central non- stimulated spinal cord
6.3661023
2.1561023
0.0069
Spinal cord
0.0050
0.0024
0.043
Notes: Significant variables are shown in bold. The residual deviance for the model includes predictor variables, whereas the null deviance for the model does not. SE,
standard error. doi:10.1371/journal.pone.0077799.t005 Table 5. Best-fit logistic regression model results for the prediction of the pain severity in rats post CCI in all experimental groups. as follows: Central and Basal.TLR2.Peripheral.TLR4
(ROC AUC: 0.76.0.66.0.63.0.6) (Table S1 in File S1). ANOVA analysis revealed the outputs generated from Periph-
eral (p = 0.009) and TLR2 (p = 0.006) were significantly different
from All output variables but not with Central (p = 0.16). The
ANOVA could not be calculated for the model generated from
TLR4 output variables owing to incompatibility of the models. (see Table 6). TLR Responsiveness as Potential Pain Biomarker The von Frey
scorewassignificantlycorrelatedwiththecombinedoutputvariables
(adjusted R-square: 0.67, P = 0.0048). Within the output variables
selected the following outputs have significant contribution: non-
stimulatedcells(P = 0.001),TLR4stimulatedPBMC(max(P = 0.02)
and slope (P = 0.03)) and TLR2 stimulated PBMC max (P = 0.02). The orders of the other modelscollected from the other subsets are as
follows: (from best to worse predictor of allodynia severity)
Peripheral.Basal.Central.TLR2 (adjusted R-square: 0.62
(P = 0.004).0.35(P = 0.03).0.16(NSP = 0.08).0.08(NSP = 0.1)
(Table S2 in File S1). Correlation between von Frey score and TLR4
only outputs was not obtained due to the refined model not being In neuronal experimental groups Model A: A combination
of all outputs best predicted the presence of pain in
rats. The panel of output variables that best predicted the
presence of pain was from the All outputs variables (Table 4). The
ROC AUC was 0.86 indicating a very good ability to determine
the presence of pain. The order of the best to worse predictor of
allodynia of the other models collected from the other subsets are Table 6. Best-fit logistic regression model results for the prediction of the pain severity in rats post CCI in neuronal and
subcutaneous experimental groups. Dataset
Variables
Estimate SE
P
Null
deviance df
Residual
deviance df
Adjusted
R-square:
P-value ANOVA
TLR2 agonist
stimulation only
Peripheral stimulated max
20.041
0.017
0.031
4.52
23 2.24
18 0.37
0.02
0.2
Peripheral stimulated min
20.073
0.058
0.23
Peripheral stimulated intercept
0.084
0.038
0.041
Central stimulated spinal cord
0.0091
0.0033 0.013
Central spinal cord supernatant
0.0046
0.0026 0.096. Central spinal cord
0.010
0.0036 0.010
Notes: Significant variables are shown in bold. One-way ANOVA was used to compare which subsets (Central/Peripheral/TLR2/TLR4 or Basal) when compare with all
outputs is a better model. The residual deviance for the model includes predictor variables, whereas the null deviance for the model does not. SE, standard error. doi:10.1371/journal.pone.0077799.t006 Notes: Significant variables are shown in bold. One-way ANOVA was used to compare which subsets (Central/Peripheral/TLR2/TLR4 or Basal) when compare with all
outputs is a better model. The residual deviance for the model includes predictor variables, whereas the null deviance for the model does not. SE, standard error. doi:10.1371/journal.pone.0077799.t006 Notes: Significant variables are shown in bold. One-way ANOVA was used to compare which subsets (Central/Peripheral/TLR2/TLR4 or Basal) when compare with all
outputs is a better model. Model C: Selected Peripheral Outputs can be Significantly
Correlated with the IL-1b from the Lumbar Spinal Cord Model C: Selected Peripheral Outputs can be Significantly
Correlated with the IL-1b from the Lumbar Spinal Cord
All experimental groups. The refined model from the
Peripheral subset correlated the best with the IL-1b released
from the basal spinal cord culture supernatant (adjusted R-square:
0.26, P = 0.003) followed by TLR4 stimulated spinal cord culture
supernatant (adjusted R-square: 0.22; P = 0.008) and lastly by
TLR2 stimulated spinal cord culture supernatant (adjusted R-
square: 0.08, P = 0.05). The same refined model was only
correlated with the TLR2 stimulated spinal cord however it did
not reach significance (adjusted R-square: 0.06, P = 0.24). Corre-
lations could not be obtained from the TLR4 stimulated spinal
cord or from the non-stimulated spinal cord. All experimental groups. The refined model from the
Peripheral subset correlated the best with the IL-1b released
from the basal spinal cord culture supernatant (adjusted R-square:
0.26, P = 0.003) followed by TLR4 stimulated spinal cord culture
supernatant (adjusted R-square: 0.22; P = 0.008) and lastly by
TLR2 stimulated spinal cord culture supernatant (adjusted R-
square: 0.08, P = 0.05). The same refined model was only
correlated with the TLR2 stimulated spinal cord however it did
not reach significance (adjusted R-square: 0.06, P = 0.24). Corre-
lations could not be obtained from the TLR4 stimulated spinal
cord or from the non-stimulated spinal cord. Increased TLR responsiveness was observed in the
isolated
PBMCs
collected
from
the
expanded
cohort
compared with pain-free participants.. The TLR2 agonist
Pam3CSK4 induced significant concentration-dependent increas-
es in IL-1b release in the isolated PBMCs collected from the
chronic pain patients (expanded cohort) when compared with
pain-free participants from the previously published cohort [21]. The clear separation between the two groups resulted in an overall
significant group effect in response to Pam3CSK4 (F3, 452 = 13,
P,0.0001; see Figure 6A). The TLR4 agonist LPS induced elevations in IL-1b in the
isolated PBMCs collected from the chronic pain patients in the
expanded cohort and in pain-free participants from the published
cohort [21]. There was a significant group difference (F1, 385 = 5,
P,0.03; see Figure 6B). Neuronal and subcutaneous experimental groups. Model C: Selected Peripheral Outputs can be Significantly
Correlated with the IL-1b from the Lumbar Spinal Cord The
refined model from the Peripheral subset best correlated with
the basal spinal cord culture supernatant (adjusted R-square: 0.56,
P = 0.0005) (Figure 5A) followed by TLR2 stimulated spinal cord
culture supernatant (adjusted R-square: 0.52; P = 0.01) (Figure 5C)
and lastly by TLR4 stimulated spinal cord culture supernatant
(adjusted R–square: 0.48, P = 0.02) (Figure 5E). The refined model
generated from output variables collected from Peripheral
location best correlated with the non-stimulated spinal cord
culture
supernatant
(adjusted
R-value:
0.56,
P = 0.0005)
(Figure 5B) followed by TLR2 stimulated spinal cord culture
supernatant (adjusted R-square: 0.52; P = 0.01) (Figure 5D) and
lastly TLR4 stimulated spinal cord culture supernatant (adjusted
R–square: 0.48, P = 0.02) (Figure 5F). Which Model is Best at Predicting Pain Presence Which Model is Best at Predicting Pain Presence Models generated from peripheral derived models from
both rats and humans have a good ability to predict
presence of pain in human. The ROC AUC generated from
the ‘‘Model rat to human’’ was 0.94 indicating a very good ability
to determine the presence of pain in humans (published cohort;
Figure 7A). Likewise, the ‘‘Model human’’ had an ROC AUC of
0.92 (Figure 7B) (Additional information of the model can be seen
in Table S3 in File S1) also indicating a very good ability to detect
the presence of pain. ANOVA analysis revealed the two models
were found to be not significantly different (Table S3 in File S1). TLR Responsiveness as Potential Pain Biomarker The residual deviance for the model includes predictor variables, whereas the null deviance for the model does not. SE, standard error. doi:10.1371/journal.pone.0077799.t006 October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org 9 TLR Responsiveness as Potential Pain Biomarker Table 7. Best-fit logistic regression model results for the prediction of the pain severity in rats post CCI in neuronal experimental
groups. Dataset
Variables
Estimate
SE
P
Null
deviance df
Residual
deviance df
Adjusted
R-square:
P-value
Complete
Peripheral non-stimulated plasma
20.013
0.007
0.088. 3.12
20 0.56
11 0.67
0.0048
Peripheral non-stimulated cells
0.12
0.027
0.00094
Peripheral TLR4 stimulated max
20.024
0.0089
0.022
Peripheral TLR4 stimulated slope
0.068
0.027
0.03
Peripheral TLR2 stimulated max
20.037
0.014
0.022
Central TLR4 stimulated spinal cord supernatant
20.023
0.015
0.15
Central non-stimulated spinal cord supernatant
0.013
0.0096
0.21
Central TLR2 stimulated spinal cord
20.0045
0.003
0.16
Central non-stimulated spinal cord
0.0042
0.0021
0.065. Peripheral plasma
21.2961022
9.8961023
0.22
Peripheral cell
7.6661022
2.7961022
0.014
Central spinal cord supernatant
21.26761022 6.04161023 0.052. Notes: Significant variables are shown in bold. The residual deviance for the model includes predictor variables, whereas the null deviance for the model does not. SE,
standard error. doi:10.1371/journal.pone.0077799.t007 Table 7. Best-fit logistic regression model results for the prediction of the pain severity in rats post CCI in neuronal experimental
groups. gression model results for the prediction of the pain severity in rats post CCI in neuronal experimental solved. ANOVA analysis revealed the model generated from All
outputvariableswassignificantlydifferentfromthefollowingoutputs solved. ANOVA analysis revealed the model generated from All
outputvariableswassignificantlydifferentfromthefollowingoutputs
collected in Central (p = 0.0089), TLR2 (p = 0.0063), Basal
(p = 0.022) but it was not different from the outputs collected from
Peripheral (p = 0.16). female, 4 male; 36–61 years old; mean age 51). In the expanded
cohort there are thirty-four chronic pain patients (25 female, 9
male, 23–64 years old, mean age 46). Additional information on
the pain diagnosis of chronic pain patients can be found in Table 9. The average duration of pain in the published cohort was 7 years
(min-max; 1–28) and for the expanded cohort was 21 years (min –
max, 3–55). The mean daily dose (oral morphine equivalent) taken
by the published cohort was (mean 6 SEM) 49613 mg and for
the expanded cohort was 1363 mg. female, 4 male; 36–61 years old; mean age 51). TLR Responsiveness as Potential Pain Biomarker In the expanded
cohort there are thirty-four chronic pain patients (25 female, 9
male, 23–64 years old, mean age 46). Additional information on
the pain diagnosis of chronic pain patients can be found in Table 9. The average duration of pain in the published cohort was 7 years
(min-max; 1–28) and for the expanded cohort was 21 years (min –
max, 3–55). The mean daily dose (oral morphine equivalent) taken
by the published cohort was (mean 6 SEM) 49613 mg and for
the expanded cohort was 1363 mg. Study 2: Chronic Pain and Pain-free Participants Study 2: Chronic Pain and Pain-free Participants
Human participant demographic data. Basic demograph-
ics are listed in Table 8. In the published cohort [21] there are
nineteen chronic pain patients (13 female, 6 male, (min-max) 33–
65 years old; mean age 52), and eleven pain-free participants (7 Human participant demographic data. Basic demograph-
ics are listed in Table 8. In the published cohort [21] there are
nineteen chronic pain patients (13 female, 6 male, (min-max) 33–
65 years old; mean age 52), and eleven pain-free participants (7 Human participant demographic data. Basic demograph-
ics are listed in Table 8. In the published cohort [21] there are
nineteen chronic pain patients (13 female, 6 male, (min-max) 33–
65 years old; mean age 52), and eleven pain-free participants (7 Model
rat
was
found
to
predict
presence
of
pain
accurately in a cohort of chronic pain participants. All
participants in the expanded cohort should be 1 (pain) however October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org 10 TLR Responsiveness as Potential Pain Biomarker Figure 5. Rat spinal cord (basal, post TLR2 and TLR4 agonist stimulation) was positively correlated with periphery outputs. IL-1b
level released from (A) basal spinal cord supernatant (P = 0.00048, adjusted R-square = 0.56) (B) basal spinal cord (P = 0.011, adjusted R-square = 0.47)
(C) spinal cord supernatant (P = 0.01, adjusted R-square = 0.52) (D) spinal cord post Pam3CSK4 (P = 0.04, adjusted R-square = 0.29) (TLR2) stimulation at
100 mg/mL (E) spinal cord supernatant (P = 0.02, adjusted R-square = 0.48) (F) spinal cord (P = 0.09, adjusted R-square = 0.26) post LPS (TLR4)
stimulation at 100 mg/mL was found to be significantly correlated with the estimated values predicted from peripheral tissue outputs in rats from
Neuronal and subcutaneous. Pearson correlation was used and data shown in panel (A, E and F) have been log transformed and linear regression with
95% confidence interval curves are shown on the graph. doi:10.1371/journal.pone.0077799.g005
TLR Responsiveness as Potential Pain Biomarker Figure 5. Rat spinal cord (basal, post TLR2 and TLR4 agonist stimulation) was positively correlated with periphery outputs. Study 2: Chronic Pain and Pain-free Participants IL-1b
level released from (A) basal spinal cord supernatant (P = 0.00048, adjusted R-square = 0.56) (B) basal spinal cord (P = 0.011, adjusted R-square = 0.47)
(C) spinal cord supernatant (P = 0.01, adjusted R-square = 0.52) (D) spinal cord post Pam3CSK4 (P = 0.04, adjusted R-square = 0.29) (TLR2) stimulation at
100 mg/mL (E) spinal cord supernatant (P = 0.02, adjusted R-square = 0.48) (F) spinal cord (P = 0.09, adjusted R-square = 0.26) post LPS (TLR4)
stimulation at 100 mg/mL was found to be significantly correlated with the estimated values predicted from peripheral tissue outputs in rats from
Neuronal and subcutaneous. Pearson correlation was used and data shown in panel (A, E and F) have been log transformed and linear regression with
95% confidence interval curves are shown on the graph. doi:10.1371/journal.pone.0077799.g005 pain conditions is lacking largely due to the inaccessibility of the
CNS [3]. However, we have recently published functional
evidence of this relationship by demonstrating that low dose
intravenous endotoxin (LPS; TLR4 activator) markedly enhanced
the flare, hyperalgesia and allodynia responses to intradermal
capsaicin in healthy volunteers [27]. Despite this important
finding, this model is not practical as a pain biomarker in large
patient populations. Hence more practical biomarkers of the
neuroimmune activation status in chronic pain are needed. In this
study we have two major findings relevant to this aim. The first is according to all models some participants were predicted to have
no pain (Figure 8). The number of participants predicted to have
no pain/pain (from best to worst predictors) by ‘‘Model rat’’ was
6/28, for ‘‘Model rat to human’’ was 21/13 and for Model
human’’ was 14/20. October 2013 | Volume 8 | Issue 10 | e77799 Discussion Sciatica was selected as it has high face
validity to the CCI model used in our animal experiments. Medication overuse headache was selected in contrast as there is
no evidence of peripheral pathology in this condition, yet we have
hypothesized that opioid-induced glial activation is a major
contributing pathology [28]. However cross-sectional studies
demonstrating correlation cannot demonstrate a causal relation-
ship. Hence our second major finding is that in a prospective
graded rat model we have shown that immune activation in
peripheral blood and in spinal cord were related to the pain state
in a ‘‘dose’’-related manner supporting a causal relationship. There are two main implications of these findings. Firstly, this
confirms the likely role of TLR signaling in human chronic pain,
providing support to the search for inhibitors of these systems as
potential new treatment for pain. Secondly, excitingly, as the
sensitivity is measured in the readily accessible tissue of peripheral
blood, these assessments have the potential to act as biomarkers. that we have replicated our earlier conclusion that in vitro PMBC
stimulation to be a biomarker of the pain state in two distinct
patient populations. Sciatica was selected as it has high face
validity to the CCI model used in our animal experiments. Medication overuse headache was selected in contrast as there is
no evidence of peripheral pathology in this condition, yet we have
hypothesized that opioid-induced glial activation is a major
contributing pathology [28]. However cross-sectional studies
demonstrating correlation cannot demonstrate a causal relation-
ship. Hence our second major finding is that in a prospective
graded rat model we have shown that immune activation in
peripheral blood and in spinal cord were related to the pain state
in a ‘‘dose’’-related manner supporting a causal relationship. There are two main implications of these findings. Firstly, this
confirms the likely role of TLR signaling in human chronic pain,
providing support to the search for inhibitors of these systems as
potential new treatment for pain. Secondly, excitingly, as the
sensitivity is measured in the readily accessible tissue of peripheral
blood, these assessments have the potential to act as biomarkers. Biomarkers of pain have several potential clinical utilities. One
important potential role would be to support patient stratification for Table 9. Primary diagnoses and medications of chronic pain
patients (n = 53). Discussion Sciatica was selected as it has high face
validity to the CCI model used in our animal experiments. Medication overuse headache was selected in contrast as there is
no evidence of peripheral pathology in this condition, yet we have
hypothesized that opioid-induced glial activation is a major
contributing pathology [28]. However cross-sectional studies
demonstrating correlation cannot demonstrate a causal relation-
ship. Hence our second major finding is that in a prospective
graded rat model we have shown that immune activation in
peripheral blood and in spinal cord were related to the pain state
in a ‘‘dose’’-related manner supporting a causal relationship. There are two main implications of these findings. Firstly, this
confirms the likely role of TLR signaling in human chronic pain,
providing support to the search for inhibitors of these systems as
potential new treatment for pain. Secondly, excitingly, as the
sensitivity is measured in the readily accessible tissue of peripheral
blood, these assessments have the potential to act as biomarkers. Biomarkers of pain have several potential clinical utilities. One
important potential role would be to support patient stratification for
Table 9. Primary diagnoses and medications of chronic pain
patients (n = 53). Diagnosis
Number (%)
Published
Cohort
Expanded
Cohort
Chronic back or shoulder or leg pain
26.3
–
Fibromyalgia
10.6
–
Sciatica
10.6
20.5
Osteoarthritis
31.5
–
Medication-overuse headache
–
79.5
Others
21*
–
Medications
Opioids
58
79.4
On medications other than opioids:
32
8.8
Not on medications
10
11.8
*Other pain diagnosis include: complex regional pain syndrome (n = 1), atypical
trigeminal neuralgia (n = 1), neuropathic Pain syndrome (n = 1) and non cardiac
chest pain (n = 1). doi:10.1371/journal.pone.0077799.t009
Figure 6. TLR agonist stimulation caused significant group
differences in the release of IL-1b in chronic pain patients and
pain-free participants. Isolated white cells obtained from new
chronic pain patients (closed circle) and pain-free controls from
previous study (open triangle) were stimulated with a range of (A)
Pam3CSK4 (TLR2) concentrations (13 pg?ml21 to 1 mg?ml21) and (B)
LPS (TLR4) concentrations (6 pg?ml21 to 10 mg?ml21) to generate the
response curves and resulted in significant group differences
(Pam3CSK4; P,0.0001 and LPS, P = 0.004). Error bars on graphs
represent standard error of the mean. doi:10.1371/journal.pone.0077799.g006 that we have replicated our earlier conclusion that in vitro PMBC
stimulation to be a biomarker of the pain state in two distinct
patient populations. Discussion Despite the wealth of pre-clinical evidence implicating TLR-
mediated neuroinflammation and chronic pain [9–11,26], the
relevance of neuroinflammation and TLR signaling in human October 2013 | Volume 8 | Issue 10 | e77799 11 PLOS ONE | www.plosone.org PLOS ONE | www.plosone.org TLR Responsiveness as Potential Pain Biomarker Table 8. Demographic summary. Published Cohort
Expanded Cohort
Chronic pain
(n = 19)
Pain-free
(n = 11)
Chronic Pain
(n = 34)
P
Gender (M/F)
6/13
4/7
9/25
–
Age (Years)
52 (33–65)
51 (36–61)
46 (23–64)
0.17
Oral morphine equivalent dose
(per day) (mg)
49613
–
1363
0.44
Duration of chronic pain (Years)
762
–
2162
,0.0001
Data were collected from medical and family history. Data are expressed as mean 6 S.E.M except age is expressed as mean 6 min–max. One-way ANOVA was used to
determine the age difference and the non-parametric Mann-Whitney test was used to daily morphine dose and duration of chronic pain between the chronic pain
groups (P-values shown). doi:10.1371/journal.pone.0077799.t008 Data were collected from medical and family history. Data are expressed as mean 6 S.E.M except age is expressed as mean 6 min–max. One-way ANOVA was used to
determine the age difference and the non-parametric Mann-Whitney test was used to daily morphine dose and duration of chronic pain between the chronic pain
groups (P-values shown). doi:10.1371/journal.pone.0077799.t008 Data were collected from medical and family history. Data are expressed as mean 6 S.E.M except age is expressed as mean 6 min–max. One-way ANOVA was used to
determine the age difference and the non-parametric Mann-Whitney test was used to daily morphine dose and duration of chronic pain between the chronic pain
groups (P-values shown). doi:10.1371/journal.pone.0077799.t008 Figure 6. TLR agonist stimulation caused significant group
differences in the release of IL-1b in chronic pain patients and
pain-free participants. Isolated white cells obtained from new
chronic pain patients (closed circle) and pain-free controls from
previous study (open triangle) were stimulated with a range of (A)
Pam3CSK4 (TLR2) concentrations (13 pg?ml21 to 1 mg?ml21) and (B)
LPS (TLR4) concentrations (6 pg?ml21 to 10 mg?ml21) to generate the
response curves and resulted in significant group differences
(Pam3CSK4; P,0.0001 and LPS, P = 0.004). Error bars on graphs
represent standard error of the mean. doi:10.1371/journal.pone.0077799.g006 that we have replicated our earlier conclusion that in vitro PMBC
stimulation to be a biomarker of the pain state in two distinct
patient populations. Discussion doi:10.1371/journal.pone.0077799.g008 enriched clinical trials or for monitoring the response to intervention
[29,30], making such trials more sensitive to interventions and more
meaningful. Another potential role is in patients who cannot
communicatewell,e.g.children,patientswithcognitiveimpairment,
or where cultural and language barriers prevent meaningful
evaluation or comparison between populations [31]. stimulation, as it allows for integrated ligand/receptor interaction,
receptor to intracellular signaling, transcriptional to translational
modification including genetic variability and epigenetic contribu-
tions. By only examining the basal response the above integration is
lost and the elicit response has proven to be important for the
discovery of potential pain biomarkers. Discussion Diagnosis
Number (%)
Published
Cohort
Expanded
Cohort
Chronic back or shoulder or leg pain
26.3
–
Fibromyalgia
10.6
–
Sciatica
10.6
20.5
Osteoarthritis
31.5
–
Medication-overuse headache
–
79.5
Others
21*
–
Medications
Opioids
58
79.4
On medications other than opioids:
32
8.8
Not on medications
10
11.8
*Other pain diagnosis include: complex regional pain syndrome (n = 1), atypical
trigeminal neuralgia (n = 1), neuropathic Pain syndrome (n = 1) and non cardiac
chest pain (n = 1). doi:10.1371/journal.pone.0077799.t009 Table 9. Primary diagnoses and medications of chronic pain
patients (n = 53). Figure 6. TLR agonist stimulation caused significant group
differences in the release of IL-1b in chronic pain patients and
pain-free participants. Isolated white cells obtained from new
chronic pain patients (closed circle) and pain-free controls from
previous study (open triangle) were stimulated with a range of (A)
Pam3CSK4 (TLR2) concentrations (13 pg?ml21 to 1 mg?ml21) and (B)
LPS (TLR4) concentrations (6 pg?ml21 to 10 mg?ml21) to generate the
response curves and resulted in significant group differences
(Pam3CSK4; P,0.0001 and LPS, P = 0.004). Error bars on graphs
represent standard error of the mean. doi:10.1371/journal.pone.0077799.g006 *Other pain diagnosis include: complex regional pain syndrome (n = 1), atypical
trigeminal neuralgia (n = 1), neuropathic Pain syndrome (n = 1) and non cardiac
chest pain (n = 1). doi:10.1371/journal.pone.0077799.t009 October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org 12 TLR Responsiveness as Potential Pain Biomarker Figure 7. Representation of ROC curves for the detection of pain presence. Models generated from (A) rat d
obtained from peripheral collected output variables. doi:10.1371/journal.pone.0077799.g007 Figure 7. Representation of ROC curves for the detection of pain presence. Models generated from (A) rat data and (B) human data
obtained from peripheral collected output variables. doi:10.1371/journal.pone.0077799.g007 October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org 13 TLR Responsiveness as Potential Pain Biomarker Figure 8. Representation of the constructed models Model rat, Model rat to human and Model human that predicted the presence
of pain in the expanded cohort. Bin center 0 represents no pain and 1 represents pain. doi:10.1371/journal.pone.0077799.g008 Figure 8. Representation of the constructed models Model rat, Model rat to human and Model human that predicted the presence
of pain in the expanded cohort. Bin center 0 represents no pain and 1 represents pain. October 2013 | Volume 8 | Issue 10 | e77799 TLR Responsiveness as Potential Pain Biomarker significantly less even though pain was experienced longer
compared with the published cohort. the surgery is indicated (eg the altered immune milieu in cancer). Hence there are several advantages of studying the neuroimmune
processes involved in pain in animals. Firstly, a study published
recently found putative pain biomarkers from blood-based RNA
transcriptome using the same preclinical graded model of pain
[32]. Many of the genes identified encode for proteins that have a
recognized role in nociceptive and immune signaling thus
providing validation for the use of this model. Secondly, animals
can be studied in a prospective manner in disease-free groups of
little heterogeneity. More importantly, CNS tissue can be accessed
directly. In this study we have shown that peripheral blood TLR
signaling sensitivity performed in a similarly predictive manner to
that from CNS-tissue sensitivity, providing construct validation to
our findings in humans. However, the discrimination of pain states
and degree of allodynia in rats was not possible on single derived
parameters from either TLR 2 or 4 stimulation, unlike in our
result in humans. From the previous study and confirmed in the current study,
chronic pain patients have greater TLR-induced IL-1b release
from PBMCs than pain-free participants. The mechanistic cause
of the PMBC phenotype that resulted in elevated TLR-induced
IL-1b release is currently unknown. It is speculated that in chronic
pain patients PBMCs are primed by previous exposure with
DAMPs and hence following subsequent exposure to a TLR
stimulus will produce an exaggerated response (increased in IL-1b
release). The technique of stimulating acutely isolated human PBMCs
with TLR agonists and measuring cytokines has been previously
used to examine innate immune function in patients. With the use
of this cell culture technique, differences in cell reactivity have
been detected between healthy controls and patients with the
following conditions: surgery [35], rheumatoid arthritis [36],
immunosuppression [37] and chronic fatigue syndrome [38]. This
supports the usefulness of this technique to reflect the dysregula-
tion of the immune function via the assessment of TLR signaling
efficiency. Further research is required to identify which popula-
tions of cells in chronic pain patients are responsible for this
increased IL-1b production. Using this acute isolation and
culturing approach, little time is provided to allow the cells to
differentiate away from their in vivo phenotype, thus providing
results as close to the in vivo setting as experimentally possible. IL-1b Expression from Lumbar Spinal Cord Predicted by
Peripheral Combination Outputs The output variables collected from peripheral sites proved to
be informative in predicting central responses. Here we demon-
strated that IL-1b expression from the rat’s lumbar spinal cord was
related to peripheral immune cell responsivity. Even though the
adjusted R-square was low, the significance of the correlation
should not be dismissed. The findings imply that samples collected
from the readily accessible peripheral circulation may provide
information as to how the CNS is responding. Thus a peripheral
marker for proinflammatory glial reactivity may be achieved
without the need to access central tissues. It is speculated that the
peripheral variables collected from chronic pain sufferers could
also predict the IL-1b expression in the central region. Further
studies are required to validate this exciting hypothesis. TLR Responsiveness as Potential Pain Biomarker We
speculate the underlying mechanisms lie in the intracellular TLR
signaling as surface TLR expression does not always correspond to
the PBMCs’ output as reported previously [37]. Models Generated from Rat Data can Predict the
Presence of Pain in Humans The model generated from the rat was found to have very good
prediction ability for the pain presence in the new cohort of
chronic pain patients. This indicates the findings from rats could
be translated to humans. The ability of the rat model to be able to
predict the presence of pain could be attributed to more output
variables being selected. Despite the high accuracy in the
prediction of pain in chronic pain participant we do not believe
that the current biomarker is as yet a diagnostic for pain. However, it does provide further evidence in humans of the
importance of peripheral and central reactivity and that this
biomarker approach might be useful in assessing the response to
selecting intervention for evaluation and reflecting the response for
novel treatments that target the TLR pathways. For it to be a
clinically usable biomarker it will need to fulfill additional criteria
such as discrimination between other disease states and sensitivity
to treatment responses. Limitations of Current Study There are several limitations in this study. Only 1 pro-
inflammatory cytokine was examined in the study as we were
testing a simplified system. As we were validating a previous
finding here we did not wish to introduce new pain mediators. Secondly, this study only undertook collection of rat biological
samples on the day of cull. It would be informative to conduct a
longitudinal study to examine the time sequence and evolution in
the sensitivity of the output variables to predict pain. Lastly, the
same pain-free participants were used as a comparison to
investigate whether increased TLR responsiveness was also
observed with the expanded subject cohort and a larger control
group would be useful. The Usefulness of Neuronal and Subcutaneous
Experimental Groups The graded CCI model allows for a better pain prediction when
chromic gut is placed both around the sciatic nerve and in the
subcutaneous space. This is supported by ROC AUC being 0.9
indicating the high accuracy to predict pain presence. The
peripheral outputs collected from the neuronal and subcutaneous
experimental groups could also be significantly correlated with
central tissue IL-1b outputs. Peripheral immune cells are known to
play a pivotal role in the establishment of chronic pain by
infiltration into central sites [33] and interact with glia causing the
release of pro-inflammatory mediators [34]. The neuronal and
subcutaneous
experimental
group
is
recommended
for
the
understanding of chronic pain as it better mimics the clinical
heterogeneous phenotype rather than the standard binomial
model of CCI [23]. How has the Rodent Work Added to Our Previous
Findings? Firstly, although cross-sectional studies in patients are easy to
perform, they suffer from the inherent weakness of potential
selection bias, and are hence at best hypothesis generating. Prospective longitudinal studies (from pre to post injury) in
humans with neuropathic pain are difficult, as studying the
patients before the onset of injury is probably only possible in post-
surgical neuropathic pain, which is only one facet of the condition. Since only a minority of patients experience such complications,
such studies are difficult because of very large sample sizes
required potentially and complicated by the pathology for which Our data have indicated that the innate immune responses
following TLR2 and TLR4 stimulation are both linked to the
presence of chronic pain. However, in humans, no group difference
was detected from the basal (i.e. unstimulated) cell activity. In
contrast, under stimulation conditions, discrimination between the
pain/no pain groups was possible. In rats, a combination of basal
output responses could identify the pain presence and the severity of
allodynia. However, more sensitive and specific findings were
obtained with the addition of the stimulated response. Therefore, it
is important to not only examine the basal but also dynamic October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org PLOS ONE | www.plosone.org 14 October 2013 | Volume 8 | Issue 10 | e77799 References Pain 153: 1555–1559. 27. Tawfik VL, LaCroix-Fralish ML, Nutile-McMenemy N, DeLeo JA (2005)
Transcriptional and translational regulation of glial activation by morphine in a
rodent model of neuropathic pain. J Pharmacol Exp Ther 313: 1239–1247. rodent model of neuropathic pain. J Pharmacol Exp Ther 313: 1239 8. Watkins LR, Maier SF (2003) Glia: a novel drug discovery target for clinical
pain. Nat Rev Drug Discov 2: 973–985. 28. Johnson JL, Hutchinson MR, Williams DB, Rolan P (2012) Medication-overuse
headache and opioid-induced hyperalgesia: A review of mechanisms, a
neuroimmune hypothesis and a novel approach to treatment. Cephalalgia : an
international journal of headache 33: 52–64. 9. Nicotra L, Loram LC, Watkins LR, Hutchinson MR (2011) Toll-like receptors
in chronic pain. Exp Neurol: 316–329. p
p
10. De Leo JA, Tawfik VL, LaCroix-Fralish ML (2006) The tetrapartite synapse:
path to CNS sensitization and chronic pain. Pain 122: 17–21. j
29. Lesko LJ, Atkinson AJ Jr (2001) Use of biomarkers and surrogate endpoints in
drug development and regulatory decision making: criteria, validation,
strategies. Annu Rev Pharmacol Toxicol 41: 347–366. 11. DeLeo JA, Tanga FY, Tawfik VL (2004) Neuroimmune activation and
neuroinflammation in chronic pain and opioid tolerance/hyperalgesia. Neuro-
scientist 10: 40–52. 30. Chizh BA, Greenspan JD, Casey KL, Nemenov MI, Treede RD (2008)
Identifying biological markers of activity in human nociceptive pathways to
facilitate analgesic drug development. Pain 140: 249–253. 12. Hutchinson MR, Shavit Y, Grace PM, Rice KC, Maier SF, et al. (2011)
Exploring the neuroimmunopharmacology of opioids: an integrative review of
mechanisms of central immune signaling and their implications for opioid
analgesia. Pharmacol Rev 63: 772–810. 31. Herr K, Coyne PJ, McCaffery M, Manworren R, Merkel S (2011) Pain
assessment in the patient unable to self-report: position statement with clinical
practice recommendations. Pain management nursing : official journal of the
American Society of Pain Management Nurses 12: 230–250. 13. Ledeboer A, Liu T, Shumilla JA, Mahoney JH, Vijay S, et al. (2006) The glial
modulatory drug AV411 attenuates mechanical allodynia in rat models of
neuropathic pain. Neuron Glia Biol 2: 279–291. 32. Yoshikawa M, Suzumura A, Tamaru T, Takayanagi T, Sawada M (1999)
Effects of phosphodiesterase inhibitors on cytokine production by microglia. Mult Scler 5: 126–133. 14. Hutchinson MR, Northcutt AL, Chao LW, Kearney JJ, Zhang Y, et al. (2008)
Minocycline suppresses morphine-induced respiratory depression, suppresses
morphine-induced reward, and enhances systemic morphine-induced analgesia. Brain Behav Immun 22: 1248–1256. 33. References 21. Kwok YH, Hutchinson MR, Gentgall MG, Rolan PE (2012) Increased
Responsiveness of Peripheral Blood Mononuclear Cells to In Vitro TLR 2, 4
and 7 Ligand Stimulation in Chronic Pain Patients. PLoS One 7: e44232. 1. Yassen A, Passier P, Furuichi Y, Dahan A (2012) Translational PK-PD modeling
in pain. Journal of pharmacokinetics and pharmacodynamics. 1. Yassen A, Passier P, Furuichi Y, Dahan A (2012) Translational PK-PD modeling
in pain. Journal of pharmacokinetics and pharmacodynamics. 2. J. Atkinson J, Colburn WA, DeGruttola VG, DeMets DL, Downing GJ, et al. (2001) Biomarkers and surrogate endpoints: preferred definitions and conceptual
framework. Clin Pharmacol Ther 69: 89–95. g
22. Grace PM, Hutchinson MR, Manavis J, Somogyi AA, Rolan PE (2010) A novel
animal model of graded neuropathic pain: Utility to investigate mechanisms of
population heterogeneity. J Neurosci Methods 193: 47–53. 3. Borsook D, Becerra L, Hargreaves R (2011) Biomarkers for chronic pain and
analgesia. Part 1: the need, reality, challenges, and solutions. Discov Med 11:
197–207. p p
g
y J
23. Bennett GJ, Xie YK (1988) A peripheral mononeuropathy in rat that produces
disorders of pain sensation like those seen in man. Pain 33: 87–107. 24. Milligan ED, Mehmert KK, Hinde JL, Harvey LO, Martin D, et al. (2000)
Thermal hyperalgesia and mechanical allodynia produced by intrathecal
administration of the human immunodeficiency virus-1 (HIV-1) envelope
glycoprotein, gp120. Brain research 861: 105–116. 4. Borsook D, Becerra L, Hargreaves R (2011) Biomarkers for chronic pain and
analgesia. Part 2: how, where, and what to look for using functional imaging. Discov Med 11: 209–219. 5. Wartolowska K, Tracey I (2009) Neuroimaging as a tool for pain diagnosis and
analgesic development. Neurotherapeutics 6: 755–760. 25. Venables WNR, Ripley BD (2002 ) Modern Applied Statistics with S. New York:
Springer. 6. Wager TD, Atlas LY, Lindquist MA, Roy M, Woo CW, e 6. Wager TD, Atlas LY, Lindquist MA, Roy M, Woo CW, et al. (2013) An fMRI-
based neurologic signature of physical pain. N Engl J Med 368: 1388–1397. p
g
26. Milligan ED, Watkins LR (2009) Pathological and protective roles of glia in
chronic pain. Nat Rev Neurosci 10: 23–36. sed neurologic signature of physical pain. N Engl J Med 368: 1388–1 7. Davis KD, Racine E, Collett B (2012) Neuroethical issues related to the use of
brain imaging: can we and should we use brain imaging as a biomarker to
diagnose chronic pain? Conclusions Best-fit logistic regression model results for the prediction of the
pain severity in rats post CCI. Table S3. Best-fit logistic
regression model from rats (Peripheral only) and from humans
to predict the presence of pain in chronic pain patients. (DOCX) In summary, our study is novel, in that the data-driven
approach was able to accurately predict pain presence and degree
of allodynia in rats after graded CCI surgery. The peripherally
derived model identified from rats could also be applied to humans
and allowed the prediction of pain presence with accuracy. In
addition, IL-1b levels in the central tissue could be predicted by
the peripheral outputs obtained from the rats. Collectively, these
results provide further evidence of the potential of peripheral cells
in being a source of potential pain biomarkers that can be easily
accessed and that supporting the role of TLR pathways in playing
a vital role in the understanding of chronic pain. TLR Responsiveness in the New Cohort of Chronic Pain
Patients The level of IL-1b released from the new cohort of chronic pain
patients was not as high as previously published chronic pain
patients [21] and could be attributed the fact that the underlying
pain is very different in medication-overuse headache and sciatica
patients compared with the heterogeneous chronic pain popula-
tion employed previously. The involvement of TLR signaling with
medication-overuse headache patients is currently unknown and
has not yet been reported. It should be noted the mean daily
morphine equivalent dose of opioids in the new cohort was October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org 15 TLR Responsiveness as Potential Pain Biomarker Author Contributions Conceived and designed the experiments: YHK PMG PER MRH. Performed the experiments: YHK LLN. Analyzed the data: YHK JT
MRH. Wrote the paper: YHK PER MRH. Conceived and designed the experiments: YHK PMG PER MRH. Performed the experiments: YHK LLN. Analyzed the data: YHK JT
MRH. Wrote the paper: YHK PER MRH. Acknowledgments We would like to thank Jacinta Johnson and Nicole Sumracki for their help
with the recruitment of participants for the expanded cohort. Supporting Information File S1
Contains: Table S1. Best-fit logistic regression model
results for the prediction of pain for rats post CCI. Table S2. File S1
Contains: Table S1. Best-fit logistic regression model
results for the prediction of pain for rats post CCI. Table S2. References Austin PJ, Moalem-Taylor G (2010) The neuro-immune balance in neuropathic
pain: involvement of inflammatory immune cells, immune-like glial cells and
cytokines. Journal of neuroimmunology 229: 26–50. 34. Grace PM, Rolan PE, Hutchinson MR (2011) Peripheral immune contributions
to the maintenance of central glial activation underlying neuropathic pain. Brain
Behav Immun: 1322–1332. 15. Hutchinson MR, Lewis SS, Coats BD, Skyba DA, Crysdale NY, et al. (2009)
Reduction of opioid withdrawal and potentiation of acute opioid analgesia by
systemic AV411 (ibudilast). Brain Behav Immun 23: 240–250. 35. Tsujimoto H, Ono S, Majima T, Efron PA, Kinoshita M, et al. (2006)
Differential toll-like receptor expression after ex vivo lipopolysaccharide
exposure in patients with sepsis and following surgical stress. Clin Immunol
119: 180–187. 16. Raghavendra V, Tanga F, DeLeo JA (2003) Inhibition of microglial activation
attenuates the development but not existing hypersensitivity in a rat model of
neuropathy. J Pharmacol Exp Ther 306: 624–630. p
y J
p
17. Miyake K (2007) Innate immune sensing of pathogens and danger signals by cell
surface Toll-like receptors. Semin Immunol 19: 3–10. 36. Kowalski ML, Wolska A, Grzegorczyk J, Hilt J, Jarzebska M, et al. (2008)
Increased responsiveness to toll-like receptor 4 stimulation in peripheral blood
mononuclear cells from patients with recent onset rheumatoid arthritis. Mediators Inflamm 2008: 132732. 18. Tanga FY, Nutile-McMenemy N, DeLeo JA (2005) The CNS role of Toll-like
receptor 4 in innate neuroimmunity and painful neuropathy. Proc Natl Acad
Sci U S A 102: 5856–5861. 37. Dunne DW, Shaw A, Bockenstedt LK, Allore HG, Chen S, et al. (2010)
Increased TLR4 expression and downstream cytokine production in immuno-
suppressed adults compared to non-immunosuppressed adults. PLoS One 5:
e11343. 19. Hutchinson MR, Zhang Y, Brown K, Coats BD, Shridhar M, et al. (2008) Non-
stereoselective reversal of neuropathic pain by naloxone and naltrexone:
involvement of toll-like receptor 4 (TLR4). Eur J Neurosci 28: 20–29. 20. Kim D, Kim MA, Cho IH, Kim MS, Lee S, et al. (2007) A critical role of toll-
like receptor 2 in nerve injury-induced spinal cord glial cell activation and pain
hypersensitivity. J Biol Chem 282: 14975–14983. 38. Chao CC, Janoff EN, Hu SX, Thomas K, Gallagher M, et al. (1991) Altered
cytokine release in peripheral blood mononuclear cell cultures from patients with
the chronic fatigue syndrome. Cytokine 3: 292–298. October 2013 | Volume 8 | Issue 10 | e77799 PLOS ONE | www.plosone.org 16
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.